fix tests

Co-Authored-By: Matthew Penner <me@matthewp.io>

.github/workflows/push.yaml

@@ -16,7 +16,7 @@ jobs:
       fail-fast: false
       matrix:
         os: [ubuntu-24.04]
-        go: ["1.24.11", "1.25.5"]
+        go: ["1.25.6"]
         goos: [linux]
         goarch: [amd64, arm64]
     permissions:
@@ -63,14 +63,14 @@ jobs:
 
       - name: Upload Release Artifact
         uses: actions/upload-artifact@b7c566a772e6b6bfb58ed0dc250532a479d7789f # v6.0.0
-        if: ${{ (github.ref == 'refs/heads/develop' || github.event_name == 'pull_request') && matrix.go == '1.24.11' }}
+        if: ${{ (github.ref == 'refs/heads/develop' || github.event_name == 'pull_request') }}
         with:
           name: wings_linux_${{ matrix.goarch }}
           path: dist/wings
 
       - name: Upload Debug Artifact
         uses: actions/upload-artifact@b7c566a772e6b6bfb58ed0dc250532a479d7789f # v6.0.0
-        if: ${{ (github.ref == 'refs/heads/develop' || github.event_name == 'pull_request') && matrix.go == '1.24.11' }}
+        if: ${{ (github.ref == 'refs/heads/develop' || github.event_name == 'pull_request') }}
         with:
           name: wings_linux_${{ matrix.goarch }}_debug
           path: dist/wings_debug

.github/workflows/release.yaml

@@ -16,7 +16,7 @@ jobs:
       - name: Setup Go
         uses: actions/setup-go@7a3fe6cf4cb3a834922a1244abfce67bcef6a0c5 # v6.2.0
         with:
-          go-version: 1.24.11
+          go-version: 1.25.6
 
       - name: Build release binaries
         env:

Dockerfile

@@ -1,5 +1,5 @@
 # Stage 1 (Build)
-FROM golang:1.24.11-alpine AS builder
+FROM golang:1.25.6-alpine AS builder
 
 ARG VERSION
 RUN apk add --update --no-cache git make mailcap

cmd/root.go

@@ -199,7 +199,7 @@ func rootCmdRun(cmd *cobra.Command, _ []string) {
 
 		// For each server ensure the minimal environment is configured for the server.
 		if err := s.CreateEnvironment(); err != nil {
-			s.Log().Error("could create base environment for server...")
+			s.Log().WithField("error", err).Error("could not create base environment for server...")
 			continue
 		}
 

config/config.go

@@ -13,7 +13,6 @@ import (
 	"regexp"
 	"strings"
 	"sync"
-	"sync/atomic"
 	"text/template"
 	"time"
 
@@ -22,7 +21,6 @@ import (
 	"github.com/apex/log"
 	"github.com/creasty/defaults"
 	"github.com/gbrlsnchs/jwt/v3"
-	"golang.org/x/sys/unix"
 	"gopkg.in/yaml.v2"
 
 	"github.com/pterodactyl/wings/system"
@@ -251,8 +249,6 @@ type SystemConfiguration struct {
 	Backups Backups `yaml:"backups"`
 
 	Transfers Transfers `yaml:"transfers"`
-
-	OpenatMode string `default:"auto" yaml:"openat_mode"`
 }
 
 type CrashDetection struct {
@@ -798,39 +794,6 @@ func getSystemName() (string, error) {
 	return release["ID"], nil
 }
 
-var (
-	openat2    atomic.Bool
-	openat2Set atomic.Bool
-)
-
-func UseOpenat2() bool {
-	if openat2Set.Load() {
-		return openat2.Load()
-	}
-	defer openat2Set.Store(true)
-
-	c := Get()
-	openatMode := c.System.OpenatMode
-	switch openatMode {
-	case "openat2":
-		openat2.Store(true)
-		return true
-	case "openat":
-		openat2.Store(false)
-		return false
-	default:
-		fd, err := unix.Openat2(unix.AT_FDCWD, "/", &unix.OpenHow{})
-		if err != nil {
-			log.WithError(err).Warn("error occurred while checking for openat2 support, falling back to openat")
-			openat2.Store(false)
-			return false
-		}
-		_ = unix.Close(fd)
-		openat2.Store(true)
-		return true
-	}
-}
-
 // Expand expands an input string by calling [os.ExpandEnv] to expand all
 // environment variables, then checks if the value is prefixed with `file://`
 // to support reading the value from a file.

docker-compose.example.yml

@@ -23,6 +23,7 @@ services:
       - "/var/log/pterodactyl/:/var/log/pterodactyl/"
       - "/tmp/pterodactyl/:/tmp/pterodactyl/"
       - "/etc/ssl/certs:/etc/ssl/certs:ro"
+	  - "/run/wings:/run/wings"
       # you may need /srv/daemon-data if you are upgrading from an old daemon
       #- "/srv/daemon-data/:/srv/daemon-data/"
       # Required for ssl if you use let's encrypt. uncomment to use.

go.mod

@@ -1,8 +1,6 @@
 module github.com/pterodactyl/wings
 
-go 1.24.0
-
-toolchain go1.24.1
+go 1.25.6
 
 require (
 	emperror.dev/errors v0.8.1
@@ -26,12 +24,13 @@ require (
 	github.com/gin-gonic/gin v1.10.1
 	github.com/glebarez/sqlite v1.11.0
 	github.com/go-co-op/gocron v1.37.0
+	github.com/goccy/go-json v0.10.5
 	github.com/google/uuid v1.6.0
 	github.com/gorilla/websocket v1.5.3
 	github.com/iancoleman/strcase v0.3.0
 	github.com/icza/dyno v0.0.0-20230330125955-09f820a8d9c0
 	github.com/juju/ratelimit v1.0.2
-	github.com/klauspost/compress v1.18.0
+	github.com/karrick/godirwalk v1.17.0
 	github.com/klauspost/pgzip v1.2.6
 	github.com/magiconair/properties v1.8.9
 	github.com/mattn/go-colorable v0.1.14
@@ -44,7 +43,7 @@ require (
 	github.com/stretchr/testify v1.10.0
 	golang.org/x/crypto v0.46.0
 	golang.org/x/sync v0.19.0
-	golang.org/x/sys v0.39.0
+	golang.org/x/time v0.0.0-20220922220347-f3bd1da661af
 	gopkg.in/ini.v1 v1.67.0
 	gopkg.in/yaml.v2 v2.4.0
 	gopkg.in/yaml.v3 v3.0.1
@@ -79,7 +78,6 @@ require (
 	github.com/go-playground/locales v0.14.1 // indirect
 	github.com/go-playground/universal-translator v0.18.1 // indirect
 	github.com/go-playground/validator/v10 v10.25.0 // indirect
-	github.com/goccy/go-json v0.10.5 // indirect
 	github.com/gogo/protobuf v1.3.2 // indirect
 	github.com/hashicorp/golang-lru/v2 v2.0.7 // indirect
 	github.com/inconshreveable/mousetrap v1.1.0 // indirect
@@ -87,6 +85,7 @@ require (
 	github.com/jinzhu/now v1.1.5 // indirect
 	github.com/json-iterator/go v1.1.12 // indirect
 	github.com/kballard/go-shellquote v0.0.0-20180428030007-95032a82bc51 // indirect
+	github.com/klauspost/compress v1.18.0 // indirect
 	github.com/klauspost/cpuid/v2 v2.2.10 // indirect
 	github.com/kr/fs v0.1.0 // indirect
 	github.com/leodido/go-urn v1.4.0 // indirect
@@ -130,9 +129,9 @@ require (
 	golang.org/x/arch v0.15.0 // indirect
 	golang.org/x/exp v0.0.0-20250305212735-054e65f0b394 // indirect
 	golang.org/x/net v0.47.0 // indirect
+	golang.org/x/sys v0.39.0 // indirect
 	golang.org/x/term v0.38.0 // indirect
 	golang.org/x/text v0.32.0 // indirect
-	golang.org/x/time v0.0.0-20220922220347-f3bd1da661af // indirect
 	golang.org/x/xerrors v0.0.0-20240903120638-7835f813f4da // indirect
 	google.golang.org/protobuf v1.36.5 // indirect
 	gotest.tools/v3 v3.0.2 // indirect

go.sum

@@ -216,6 +216,8 @@ github.com/jstemmer/go-junit-report v0.0.0-20190106144839-af01ea7f8024/go.mod h1
 github.com/jstemmer/go-junit-report v0.9.1/go.mod h1:Brl9GWCQeLvo8nXZwPNNblvFj/XSXhF0NWZEnDohbsk=
 github.com/juju/ratelimit v1.0.2 h1:sRxmtRiajbvrcLQT7S+JbqU0ntsb9W2yhSdNN8tWfaI=
 github.com/juju/ratelimit v1.0.2/go.mod h1:qapgC/Gy+xNh9UxzV13HGGl/6UXNN+ct+vwSgWNm/qk=
+github.com/karrick/godirwalk v1.17.0 h1:b4kY7nqDdioR/6qnbHQyDvmA17u5G1cZ6J+CZXwSWoI=
+github.com/karrick/godirwalk v1.17.0/go.mod h1:j4mkqPuvaLI8mp1DroR3P6ad7cyYd4c1qeJ3RV7ULlk=
 github.com/kballard/go-shellquote v0.0.0-20180428030007-95032a82bc51 h1:Z9n2FFNUXsshfwJMBgNA0RU6/i7WVaAegv3PtuIHPMs=
 github.com/kballard/go-shellquote v0.0.0-20180428030007-95032a82bc51/go.mod h1:CzGEWj7cYgsdH8dAjBGEr58BoE7ScuLd+fwFZ44+/x8=
 github.com/kisielk/errcheck v1.5.0/go.mod h1:pFxgyoBC7bSaBwPgfKdkLd5X25qrDl4LWUI2bnpBCr8=

internal/quota_writer.go

@@ -1,26 +1,26 @@
 // SPDX-License-Identifier: MIT
 // SPDX-FileCopyrightText: Copyright (c) 2024 Matthew Penner
 
-package ufs
+package internal
 
 import (
 	"io"
+	"os"
 	"sync/atomic"
 )
 
 // CountedWriter is a writer that counts the amount of data written to the
 // underlying writer.
 type CountedWriter struct {
-	File
-
+	file    *os.File
 	counter atomic.Int64
 	err     error
 }
 
 // NewCountedWriter returns a new countedWriter that counts the amount of bytes
 // written to the underlying writer.
-func NewCountedWriter(f File) *CountedWriter {
-	return &CountedWriter{File: f}
+func NewCountedWriter(f *os.File) *CountedWriter {
+	return &CountedWriter{file: f}
 }
 
 // BytesWritten returns the amount of bytes that have been written to the
@@ -46,7 +46,7 @@ func (w *CountedWriter) Write(p []byte) (int, error) {
 	}
 
 	// Write is a very simple operation for us to handle.
-	n, err := w.File.Write(p)
+	n, err := w.file.Write(p)
 	w.counter.Add(int64(n))
 	w.err = err
 
@@ -59,7 +59,7 @@ func (w *CountedWriter) Write(p []byte) (int, error) {
 
 func (w *CountedWriter) ReadFrom(r io.Reader) (n int64, err error) {
 	cr := NewCountedReader(r)
-	n, err = w.File.ReadFrom(cr)
+	n, err = w.file.ReadFrom(cr)
 	w.counter.Add(n)
 	return
 }

internal/ufs/LICENSE

@@ -1,21 +0,0 @@
-MIT License
-
-Copyright (c) 2024 Matthew Penner
-
-Permission is hereby granted, free of charge, to any person obtaining a copy
-of this software and associated documentation files (the "Software"), to deal
-in the Software without restriction, including without limitation the rights
-to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
-copies of the Software, and to permit persons to whom the Software is
-furnished to do so, subject to the following conditions:
-
-The above copyright notice and this permission notice shall be included in all
-copies or substantial portions of the Software.
-
-THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
-SOFTWARE.

internal/ufs/README.md

@@ -1,21 +0,0 @@
-# Filesystem
-
-Coming Soon™
-
-> TODO
-
-## Licensing
-
-Most code in this package is licensed under `MIT` with some exceptions.
-
-The following files are licensed under `BSD-3-Clause` due to them being copied
-verbatim or derived from [Go](https://go.dev)'s source code.
-
-- [`file_posix.go`](./file_posix.go)
-- [`mkdir_unix.go`](./mkdir_unix.go)
-- [`path_unix.go`](./path_unix.go)
-- [`removeall_unix.go`](./removeall_unix.go)
-- [`stat_unix.go`](./stat_unix.go)
-- [`walk.go`](./walk.go)
-
-These changes are not associated with nor endorsed by The Go Authors.

internal/ufs/doc.go

@@ -1,12 +0,0 @@
-// SPDX-License-Identifier: MIT
-// SPDX-FileCopyrightText: Copyright (c) 2024 Matthew Penner
-
-// Package ufs provides an abstraction layer for performing I/O on filesystems.
-// This package is designed to be used in-place of standard `os` package I/O
-// calls, and is not designed to be used as a generic filesystem abstraction
-// like the `io/fs` package.
-//
-// The primary use-case of this package was to provide a "chroot-like" `os`
-// wrapper, so we can safely sandbox I/O operations within a directory and
-// use untrusted arbitrary paths.
-package ufs

internal/ufs/error.go

@@ -1,183 +0,0 @@
-// SPDX-License-Identifier: MIT
-// SPDX-FileCopyrightText: Copyright (c) 2024 Matthew Penner
-
-package ufs
-
-import (
-	"errors"
-	iofs "io/fs"
-	"os"
-	"syscall"
-
-	"golang.org/x/sys/unix"
-)
-
-var (
-	// ErrIsDirectory is an error for when an operation that operates only on
-	// files is given a path to a directory.
-	ErrIsDirectory = errors.New("is a directory")
-	// ErrNotDirectory is an error for when an operation that operates only on
-	// directories is given a path to a file.
-	ErrNotDirectory = errors.New("not a directory")
-	// ErrBadPathResolution is an error for when a sand-boxed filesystem
-	// resolves a given path to a forbidden location.
-	ErrBadPathResolution = errors.New("bad path resolution")
-	// ErrNotRegular is an error for when an operation that operates only on
-	// regular files is passed something other than a regular file.
-	ErrNotRegular = errors.New("not a regular file")
-
-	// ErrClosed is an error for when an entry was accessed after being closed.
-	ErrClosed = iofs.ErrClosed
-	// ErrInvalid is an error for when an invalid argument was used.
-	ErrInvalid = iofs.ErrInvalid
-	// ErrExist is an error for when an entry already exists.
-	ErrExist = iofs.ErrExist
-	// ErrNotExist is an error for when an entry does not exist.
-	ErrNotExist = iofs.ErrNotExist
-	// ErrPermission is an error for when the required permissions to perform an
-	// operation are missing.
-	ErrPermission = iofs.ErrPermission
-)
-
-// LinkError records an error during a link or symlink or rename
-// system call and the paths that caused it.
-type LinkError = os.LinkError
-
-// PathError records an error and the operation and file path that caused it.
-type PathError = iofs.PathError
-
-// SyscallError records an error from a specific system call.
-type SyscallError = os.SyscallError
-
-// NewSyscallError returns, as an error, a new [*os.SyscallError] with the
-// given system call name and error details. As a convenience, if err is nil,
-// [NewSyscallError] returns nil.
-func NewSyscallError(syscall string, err error) error {
-	return os.NewSyscallError(syscall, err)
-}
-
-// convertErrorType converts errors into our custom errors to ensure consistent
-// error values.
-func convertErrorType(err error) error {
-	if err == nil {
-		return nil
-	}
-
-	var pErr *PathError
-	if errors.As(err, &pErr) {
-		if errno, ok := pErr.Err.(syscall.Errno); ok {
-			return errnoToPathError(errno, pErr.Op, pErr.Path)
-		}
-		return pErr
-	}
-
-	// If the error wasn't already a path error and is a errno, wrap it with
-	// details that we can use to know there is something wrong with our
-	// error wrapping somewhere.
-	var errno syscall.Errno
-	if errors.As(err, &errno) {
-		return &PathError{
-			Op:   "!(UNKNOWN)",
-			Path: "!(UNKNOWN)",
-			Err:  err,
-		}
-	}
-
-	return err
-}
-
-// ensurePathError ensures that err is a PathError. The op and path arguments
-// are only used of the error isn't already a PathError.
-func ensurePathError(err error, op, path string) error {
-	if err == nil {
-		return nil
-	}
-
-	// Check if the error is already a PathError.
-	var pErr *PathError
-	if errors.As(err, &pErr) {
-		// If underlying error is a errno, convert it.
-		//
-		// DO NOT USE `errors.As` or whatever here, the error will either be
-		// an errno, or it will be wrapped already.
-		if errno, ok := pErr.Err.(syscall.Errno); ok {
-			return errnoToPathError(errno, pErr.Op, pErr.Path)
-		}
-		// Return the PathError as-is without modification.
-		return pErr
-	}
-
-	// If the error is directly an errno, convert it to a PathError.
-	var errno syscall.Errno
-	if errors.As(err, &errno) {
-		return errnoToPathError(errno, op, path)
-	}
-
-	// Otherwise just wrap it as a PathError without any additional changes.
-	return &PathError{
-		Op:   op,
-		Path: path,
-		Err:  err,
-	}
-}
-
-// errnoToPathError converts an errno into a proper path error.
-func errnoToPathError(err syscall.Errno, op, path string) error {
-	switch err {
-	// File exists
-	case unix.EEXIST:
-		return &PathError{
-			Op:   op,
-			Path: path,
-			Err:  ErrExist,
-		}
-	// Is a directory
-	case unix.EISDIR:
-		return &PathError{
-			Op:   op,
-			Path: path,
-			Err:  ErrIsDirectory,
-		}
-	// Not a directory
-	case unix.ENOTDIR:
-		return &PathError{
-			Op:   op,
-			Path: path,
-			Err:  ErrNotDirectory,
-		}
-	// No such file or directory
-	case unix.ENOENT:
-		return &PathError{
-			Op:   op,
-			Path: path,
-			Err:  ErrNotExist,
-		}
-	// Operation not permitted
-	case unix.EPERM:
-		return &PathError{
-			Op:   op,
-			Path: path,
-			Err:  ErrPermission,
-		}
-	// Invalid cross-device link
-	case unix.EXDEV:
-		return &PathError{
-			Op:   op,
-			Path: path,
-			Err:  ErrBadPathResolution,
-		}
-	// Too many levels of symbolic links
-	case unix.ELOOP:
-		return &PathError{
-			Op:   op,
-			Path: path,
-			Err:  ErrBadPathResolution,
-		}
-	default:
-		return &PathError{
-			Op:   op,
-			Path: path,
-			Err:  err,
-		}
-	}
-}

internal/ufs/file.go

@@ -1,180 +0,0 @@
-// SPDX-License-Identifier: MIT
-// SPDX-FileCopyrightText: Copyright (c) 2024 Matthew Penner
-
-package ufs
-
-import (
-	"io"
-	iofs "io/fs"
-
-	"golang.org/x/sys/unix"
-)
-
-// DirEntry is an entry read from a directory.
-type DirEntry = iofs.DirEntry
-
-// File describes readable and/or writable file from a Filesystem.
-type File interface {
-	// Name returns the base name of the file.
-	Name() string
-
-	// Stat returns the FileInfo structure describing the file.
-	// If there is an error, it will be of type *PathError.
-	Stat() (FileInfo, error)
-
-	// ReadDir reads the contents of the directory associated with the file f
-	// and returns a slice of DirEntry values in directory order.
-	// Subsequent calls on the same file will yield later DirEntry records in the directory.
-	//
-	// If n > 0, ReadDir returns at most n DirEntry records.
-	// In this case, if ReadDir returns an empty slice, it will return an error explaining why.
-	// At the end of a directory, the error is io.EOF.
-	//
-	// If n <= 0, ReadDir returns all the DirEntry records remaining in the directory.
-	// When it succeeds, it returns a nil error (not io.EOF).
-	ReadDir(n int) ([]DirEntry, error)
-
-	// Readdirnames reads the contents of the directory associated with file
-	// and returns a slice of up to n names of files in the directory,
-	// in directory order. Subsequent calls on the same file will yield
-	// further names.
-	//
-	// If n > 0, Readdirnames returns at most n names. In this case, if
-	// Readdirnames returns an empty slice, it will return a non-nil error
-	// explaining why. At the end of a directory, the error is io.EOF.
-	//
-	// If n <= 0, Readdirnames returns all the names from the directory in
-	// a single slice. In this case, if Readdirnames succeeds (reads all
-	// the way to the end of the directory), it returns the slice and a
-	// nil error. If it encounters an error before the end of the
-	// directory, Readdirnames returns the names read until that point and
-	// a non-nil error.
-	Readdirnames(n int) (names []string, err error)
-
-	// Fd returns the integer Unix file descriptor referencing the open file.
-	// If f is closed, the file descriptor becomes invalid.
-	// If f is garbage collected, a finalizer may close the file descriptor,
-	// making it invalid; see runtime.SetFinalizer for more information on when
-	// a finalizer might be run. On Unix systems this will cause the SetDeadline
-	// methods to stop working.
-	// Because file descriptors can be reused, the returned file descriptor may
-	// only be closed through the Close method of f, or by its finalizer during
-	// garbage collection. Otherwise, during garbage collection the finalizer
-	// may close an unrelated file descriptor with the same (reused) number.
-	//
-	// As an alternative, see the f.SyscallConn method.
-	Fd() uintptr
-
-	// Truncate changes the size of the file.
-	// It does not change the I/O offset.
-	// If there is an error, it will be of type *PathError.
-	Truncate(size int64) error
-
-	io.Closer
-
-	io.Reader
-	io.ReaderAt
-	io.ReaderFrom
-
-	io.Writer
-	io.WriterAt
-
-	io.Seeker
-}
-
-// FileInfo describes a file and is returned by Stat and Lstat.
-type FileInfo = iofs.FileInfo
-
-// FileMode represents a file's mode and permission bits.
-// The bits have the same definition on all systems, so that
-// information about files can be moved from one system
-// to another portably. Not all bits apply to all systems.
-// The only required bit is ModeDir for directories.
-type FileMode = iofs.FileMode
-
-// The defined file mode bits are the most significant bits of the FileMode.
-// The nine least-significant bits are the standard Unix rwxrwxrwx permissions.
-// The values of these bits should be considered part of the public API and
-// may be used in wire protocols or disk representations: they must not be
-// changed, although new bits might be added.
-const (
-	// ModeDir represents a directory.
-	// d: is a directory
-	ModeDir = iofs.ModeDir
-	// ModeAppend represents an append-only file.
-	// a: append-only
-	ModeAppend = iofs.ModeAppend
-	// ModeExclusive represents an exclusive file.
-	// l: exclusive use
-	ModeExclusive = iofs.ModeExclusive
-	// ModeTemporary .
-	// T: temporary file; Plan 9 only.
-	ModeTemporary = iofs.ModeTemporary
-	// ModeSymlink .
-	// L: symbolic link.
-	ModeSymlink = iofs.ModeSymlink
-	// ModeDevice .
-	// D: device file.
-	ModeDevice = iofs.ModeDevice
-	// ModeNamedPipe .
-	// p: named pipe (FIFO)
-	ModeNamedPipe = iofs.ModeNamedPipe
-	// ModeSocket .
-	// S: Unix domain socket.
-	ModeSocket = iofs.ModeSocket
-	// ModeSetuid .
-	// u: setuid
-	ModeSetuid = iofs.ModeSetuid
-	// ModeSetgid .
-	// g: setgid
-	ModeSetgid = iofs.ModeSetgid
-	// ModeCharDevice .
-	// c: Unix character device, when ModeDevice is set
-	ModeCharDevice = iofs.ModeCharDevice
-	// ModeSticky .
-	// t: sticky
-	ModeSticky = iofs.ModeSticky
-	// ModeIrregular .
-	// ?: non-regular file; nothing else is known about this file.
-	ModeIrregular = iofs.ModeIrregular
-
-	// ModeType .
-	ModeType = iofs.ModeType
-
-	// ModePerm .
-	// Unix permission bits, 0o777.
-	ModePerm = iofs.ModePerm
-)
-
-// Re-using the same names as Go's official `unix` and `os` package do.
-const (
-	// O_RDONLY opens the file read-only.
-	O_RDONLY = unix.O_RDONLY
-	// O_WRONLY opens the file write-only.
-	O_WRONLY = unix.O_WRONLY
-	// O_RDWR opens the file read-write.
-	O_RDWR = unix.O_RDWR
-	// O_APPEND appends data to the file when writing.
-	O_APPEND = unix.O_APPEND
-	// O_CREATE creates a new file if it doesn't exist.
-	O_CREATE = unix.O_CREAT
-	// O_EXCL is used with O_CREATE, file must not exist.
-	O_EXCL = unix.O_EXCL
-	// O_SYNC open for synchronous I/O.
-	O_SYNC = unix.O_SYNC
-	// O_TRUNC truncates regular writable file when opened.
-	O_TRUNC = unix.O_TRUNC
-	// O_DIRECTORY opens a directory only. If the entry is not a directory an
-	// error will be returned.
-	O_DIRECTORY = unix.O_DIRECTORY
-	// O_NOFOLLOW opens the exact path given without following symlinks.
-	O_NOFOLLOW  = unix.O_NOFOLLOW
-	O_CLOEXEC   = unix.O_CLOEXEC
-	O_LARGEFILE = unix.O_LARGEFILE
-)
-
-const (
-	AT_SYMLINK_NOFOLLOW = unix.AT_SYMLINK_NOFOLLOW
-	AT_REMOVEDIR        = unix.AT_REMOVEDIR
-	AT_EMPTY_PATH       = unix.AT_EMPTY_PATH
-)

internal/ufs/file_posix.go

@@ -1,49 +0,0 @@
-// SPDX-License-Identifier: BSD-3-Clause
-
-// Code in this file was copied from `go/src/os/file_posix.go`.
-
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the `go.LICENSE` file.
-
-//go:build unix || (js && wasm) || wasip1 || windows
-
-package ufs
-
-import (
-	"golang.org/x/sys/unix"
-)
-
-// ignoringEINTR makes a function call and repeats it if it returns an
-// EINTR error. This appears to be required even though we install all
-// signal handlers with SA_RESTART: see https://go.dev/issue/22838,
-// https://go.dev/issue/38033, https://go.dev/issue/38836,
-// https://go.dev/issue/40846. Also, https://go.dev/issue/20400 and
-// https://go.dev/issue/36644 are issues in which a signal handler is
-// installed without setting SA_RESTART. None of these are the common case,
-// but there are enough of them that it seems that we can't avoid
-// an EINTR loop.
-func ignoringEINTR(fn func() error) error {
-	for {
-		err := fn()
-		if err != unix.EINTR {
-			return err
-		}
-	}
-}
-
-// syscallMode returns the syscall-specific mode bits from Go's portable mode bits.
-func syscallMode(i FileMode) (o FileMode) {
-	o |= i.Perm()
-	if i&ModeSetuid != 0 {
-		o |= unix.S_ISUID
-	}
-	if i&ModeSetgid != 0 {
-		o |= unix.S_ISGID
-	}
-	if i&ModeSticky != 0 {
-		o |= unix.S_ISVTX
-	}
-	// No mapping for Go's ModeTemporary (plan9 only).
-	return
-}

internal/ufs/filesystem.go

@@ -1,168 +0,0 @@
-// SPDX-License-Identifier: MIT
-// SPDX-FileCopyrightText: Copyright (c) 2024 Matthew Penner
-
-package ufs
-
-import (
-	"time"
-)
-
-// Filesystem represents a filesystem capable of performing I/O operations.
-type Filesystem interface {
-	// Chmod changes the mode of the named file to mode.
-	//
-	// If the file is a symbolic link, it changes the mode of the link's target.
-	// If there is an error, it will be of type *PathError.
-	//
-	// A different subset of the mode bits are used, depending on the
-	// operating system.
-	//
-	// On Unix, the mode's permission bits, ModeSetuid, ModeSetgid, and
-	// ModeSticky are used.
-	//
-	// On Windows, only the 0200 bit (owner writable) of mode is used; it
-	// controls whether the file's read-only attribute is set or cleared.
-	// The other bits are currently unused. For compatibility with Go 1.12
-	// and earlier, use a non-zero mode. Use mode 0400 for a read-only
-	// file and 0600 for a readable+writable file.
-	//
-	// On Plan 9, the mode's permission bits, ModeAppend, ModeExclusive,
-	// and ModeTemporary are used.
-	Chmod(name string, mode FileMode) error
-
-	// Chown changes the numeric uid and gid of the named file.
-	//
-	// If the file is a symbolic link, it changes the uid and gid of the link's target.
-	// A uid or gid of -1 means to not change that value.
-	// If there is an error, it will be of type *PathError.
-	//
-	// On Windows or Plan 9, Chown always returns the syscall.EWINDOWS or
-	// EPLAN9 error, wrapped in *PathError.
-	Chown(name string, uid, gid int) error
-
-	// Lchown changes the numeric uid and gid of the named file.
-	//
-	// If the file is a symbolic link, it changes the uid and gid of the link itself.
-	// If there is an error, it will be of type *PathError.
-	//
-	// On Windows, it always returns the syscall.EWINDOWS error, wrapped
-	// in *PathError.
-	Lchown(name string, uid, gid int) error
-
-	// Chtimes changes the access and modification times of the named
-	// file, similar to the Unix utime() or utimes() functions.
-	//
-	// The underlying filesystem may truncate or round the values to a
-	// less precise time unit.
-	//
-	// If there is an error, it will be of type *PathError.
-	Chtimes(name string, atime, mtime time.Time) error
-
-	// Create creates or truncates the named file. If the file already exists,
-	// it is truncated.
-	//
-	// If the file does not exist, it is created with mode 0666
-	// (before umask). If successful, methods on the returned File can
-	// be used for I/O; the associated file descriptor has mode O_RDWR.
-	// If there is an error, it will be of type *PathError.
-	Create(name string) (File, error)
-
-	// Mkdir creates a new directory with the specified name and permission
-	// bits (before umask).
-	//
-	// If there is an error, it will be of type *PathError.
-	Mkdir(name string, perm FileMode) error
-
-	// MkdirAll creates a directory named path, along with any necessary
-	// parents, and returns nil, or else returns an error.
-	//
-	// The permission bits perm (before umask) are used for all
-	// directories that MkdirAll creates.
-	// If path is already a directory, MkdirAll does nothing
-	// and returns nil.
-	MkdirAll(path string, perm FileMode) error
-
-	// Open opens the named file for reading.
-	//
-	// If successful, methods on the returned file can be used for reading; the
-	// associated file descriptor has mode O_RDONLY.
-	//
-	// If there is an error, it will be of type *PathError.
-	Open(name string) (File, error)
-
-	// OpenFile is the generalized open call; most users will use Open
-	// or Create instead. It opens the named file with specified flag
-	// (O_RDONLY etc.).
-	//
-	// If the file does not exist, and the O_CREATE flag
-	// is passed, it is created with mode perm (before umask). If successful,
-	// methods on the returned File can be used for I/O.
-	//
-	// If there is an error, it will be of type *PathError.
-	OpenFile(name string, flag int, perm FileMode) (File, error)
-
-	// ReadDir reads the named directory,
-	//
-	// returning all its directory entries sorted by filename.
-	// If an error occurs reading the directory, ReadDir returns the entries it
-	// was able to read before the error, along with the error.
-	ReadDir(name string) ([]DirEntry, error)
-
-	// Remove removes the named file or (empty) directory.
-	//
-	// If there is an error, it will be of type *PathError.
-	Remove(name string) error
-
-	// RemoveAll removes path and any children it contains.
-	//
-	// It removes everything it can but returns the first error
-	// it encounters. If the path does not exist, RemoveAll
-	// returns nil (no error).
-	//
-	// If there is an error, it will be of type *PathError.
-	RemoveAll(path string) error
-
-	// Rename renames (moves) oldpath to newpath.
-	//
-	// If newpath already exists and is not a directory, Rename replaces it.
-	// OS-specific restrictions may apply when oldpath and newpath are in different directories.
-	// Even within the same directory, on non-Unix platforms Rename is not an atomic operation.
-	//
-	// If there is an error, it will be of type *LinkError.
-	Rename(oldname, newname string) error
-
-	// Stat returns a FileInfo describing the named file.
-	//
-	// If there is an error, it will be of type *PathError.
-	Stat(name string) (FileInfo, error)
-
-	// Lstat returns a FileInfo describing the named file.
-	//
-	// If the file is a symbolic link, the returned FileInfo
-	// describes the symbolic link. Lstat makes no attempt to follow the link.
-	//
-	// If there is an error, it will be of type *PathError.
-	Lstat(name string) (FileInfo, error)
-
-	// Symlink creates newname as a symbolic link to oldname.
-	//
-	// On Windows, a symlink to a non-existent oldname creates a file symlink;
-	// if oldname is later created as a directory the symlink will not work.
-	//
-	// If there is an error, it will be of type *LinkError.
-	Symlink(oldname, newname string) error
-
-	// WalkDir walks the file tree rooted at root, calling fn for each file or
-	// directory in the tree, including root.
-	//
-	// All errors that arise visiting files and directories are filtered by fn:
-	// see the [WalkDirFunc] documentation for details.
-	//
-	// The files are walked in lexical order, which makes the output deterministic
-	// but requires WalkDir to read an entire directory into memory before proceeding
-	// to walk that directory.
-	//
-	// WalkDir does not follow symbolic links found in directories,
-	// but if root itself is a symbolic link, its target will be walked.
-	WalkDir(root string, fn WalkDirFunc) error
-}

internal/ufs/fs_quota.go

@@ -1,169 +0,0 @@
-// SPDX-License-Identifier: MIT
-// SPDX-FileCopyrightText: Copyright (c) 2024 Matthew Penner
-
-package ufs
-
-import (
-	"sync/atomic"
-)
-
-// Quota is a wrapper around [*UnixFS] that provides the ability to limit the
-// disk usage of the filesystem.
-//
-// NOTE: this is not a full complete quota filesystem, it provides utilities for
-// tracking and checking the usage of the filesystem. The only operation that is
-// automatically accounted against the quota are file deletions.
-type Quota struct {
-	// fs is the underlying filesystem that runs the actual I/O operations.
-	*UnixFS
-
-	// limit is the size limit of the filesystem.
-	//
-	// limit is atomic to allow the limit to be safely changed after the
-	// filesystem was created.
-	//
-	// A limit of `-1` disables any write operation from being performed.
-	// A limit of `0` disables any limit checking.
-	limit atomic.Int64
-
-	// usage is the current usage of the filesystem.
-	//
-	// If usage is set to `-1`, it hasn't been calculated yet.
-	usage atomic.Int64
-}
-
-// NewQuota creates a new Quota filesystem using an existing UnixFS and a limit.
-func NewQuota(fs *UnixFS, limit int64) *Quota {
-	qfs := Quota{UnixFS: fs}
-	qfs.limit.Store(limit)
-	return &qfs
-}
-
-// Close closes the filesystem.
-func (fs *Quota) Close() (err error) {
-	err = fs.UnixFS.Close()
-	return
-}
-
-// Limit returns the limit of the filesystem.
-func (fs *Quota) Limit() int64 {
-	return fs.limit.Load()
-}
-
-// SetLimit returns the limit of the filesystem.
-func (fs *Quota) SetLimit(newLimit int64) int64 {
-	return fs.limit.Swap(newLimit)
-}
-
-// Usage returns the current usage of the filesystem.
-func (fs *Quota) Usage() int64 {
-	return fs.usage.Load()
-}
-
-// SetUsage updates the total usage of the filesystem.
-func (fs *Quota) SetUsage(newUsage int64) int64 {
-	return fs.usage.Swap(newUsage)
-}
-
-// Add adds `i` to the tracked usage total.
-func (fs *Quota) Add(i int64) int64 {
-	usage := fs.Usage()
-
-	// If adding `i` to the usage will put us below 0, cap it. (`i` can be negative)
-	if usage+i < 0 {
-		fs.usage.Store(0)
-		return 0
-	}
-	return fs.usage.Add(i)
-}
-
-// CanFit checks if the given size can fit in the filesystem without exceeding
-// the limit of the filesystem.
-func (fs *Quota) CanFit(size int64) bool {
-	// Get the size limit of the filesystem.
-	limit := fs.Limit()
-	switch limit {
-	case -1:
-		// A limit of -1 means no write operations are allowed.
-		return false
-	case 0:
-		// A limit of 0 means unlimited.
-		return true
-	}
-
-	// Any other limit is a value we need to check.
-	usage := fs.Usage()
-	if usage == -1 {
-		// We don't know what the current usage is yet.
-		return true
-	}
-
-	// If the current usage + the requested size are under the limit of the
-	// filesystem, allow it.
-	if usage+size <= limit {
-		return true
-	}
-
-	// Welp, the size would exceed the limit of the filesystem, deny it.
-	return false
-}
-
-// Remove removes the named file or (empty) directory.
-//
-// If there is an error, it will be of type [*PathError].
-func (fs *Quota) Remove(name string) error {
-	// For information on why this interface is used here, check its
-	// documentation.
-	s, err := fs.RemoveStat(name)
-	if err != nil {
-		return err
-	}
-
-	// Don't reduce the quota's usage as `name` is not a regular file.
-	if !s.Mode().IsRegular() {
-		return nil
-	}
-
-	// Remove the size of the deleted file from the quota usage.
-	fs.Add(-s.Size())
-	return nil
-}
-
-// RemoveAll removes path and any children it contains.
-//
-// It removes everything it can but returns the first error
-// it encounters. If the path does not exist, RemoveAll
-// returns nil (no error).
-//
-// If there is an error, it will be of type [*PathError].
-func (fs *Quota) RemoveAll(name string) error {
-	name, err := fs.unsafePath(name)
-	if err != nil {
-		return err
-	}
-	// While removeAll internally checks this, I want to make sure we check it
-	// and return the proper error so our tests can ensure that this will never
-	// be a possibility.
-	if name == "." {
-		return &PathError{
-			Op:   "removeall",
-			Path: name,
-			Err:  ErrBadPathResolution,
-		}
-	}
-	return fs.removeAll(name)
-}
-
-func (fs *Quota) removeAll(path string) error {
-	return removeAll(fs, path)
-}
-
-func (fs *Quota) unlinkat(dirfd int, name string, flags int) error {
-	if flags == 0 {
-		s, err := fs.Lstatat(dirfd, name)
-		if err == nil && s.Mode().IsRegular() {
-			fs.Add(-s.Size())
-		}
-	}
-	return fs.UnixFS.unlinkat(dirfd, name, flags)
-}

internal/ufs/fs_unix.go

@@ -1,895 +0,0 @@
-// SPDX-License-Identifier: MIT
-// SPDX-FileCopyrightText: Copyright (c) 2024 Matthew Penner
-
-//go:build unix
-
-package ufs
-
-import (
-	"errors"
-	"fmt"
-	"os"
-	"path/filepath"
-	"strconv"
-	"strings"
-	"time"
-
-	"golang.org/x/sys/unix"
-)
-
-// UnixFS is a filesystem that uses the unix package to make io calls.
-//
-// This is used for proper sand-boxing and full control over the exact syscalls
-// being performed.
-type UnixFS struct {
-	// basePath is the base path for file operations to take place in.
-	basePath string
-
-	// useOpenat2 controls whether the `openat2` syscall is used instead of the
-	// older `openat` syscall.
-	useOpenat2 bool
-}
-
-// NewUnixFS creates a new sandboxed unix filesystem. BasePath is used as the
-// sandbox path, operations on BasePath itself are not allowed, but any
-// operations on its descendants are. Symlinks pointing outside BasePath are
-// checked and prevented from enabling an escape in a non-raceable manor.
-func NewUnixFS(basePath string, useOpenat2 bool) (*UnixFS, error) {
-	basePath = strings.TrimSuffix(basePath, "/")
-	fs := &UnixFS{
-		basePath:   basePath,
-		useOpenat2: useOpenat2,
-	}
-	return fs, nil
-}
-
-// BasePath returns the base path of the UnixFS sandbox, file operations
-// pointing outside this path are prohibited and will be blocked by all
-// operations implemented by UnixFS.
-func (fs *UnixFS) BasePath() string {
-	return fs.basePath
-}
-
-// Close releases the file descriptor used to sandbox operations within the
-// base path of the filesystem.
-func (fs *UnixFS) Close() error {
-	return nil
-}
-
-// Chmod changes the mode of the named file to mode.
-//
-// If the file is a symbolic link, it changes the mode of the link's target.
-// If there is an error, it will be of type *PathError.
-//
-// A different subset of the mode bits are used, depending on the
-// operating system.
-//
-// On Unix, the mode's permission bits, ModeSetuid, ModeSetgid, and
-// ModeSticky are used.
-//
-// On Windows, only the 0200 bit (owner writable) of mode is used; it
-// controls whether the file's read-only attribute is set or cleared.
-// The other bits are currently unused. For compatibility with Go 1.12
-// and earlier, use a non-zero mode. Use mode 0400 for a read-only
-// file and 0600 for a readable+writable file.
-//
-// On Plan 9, the mode's permission bits, ModeAppend, ModeExclusive,
-// and ModeTemporary are used.
-func (fs *UnixFS) Chmod(name string, mode FileMode) error {
-	dirfd, name, closeFd, err := fs.safePath(name)
-	defer closeFd()
-	if err != nil {
-		return err
-	}
-	return fs.fchmodat("chmod", dirfd, name, mode)
-}
-
-// Chmodat is like Chmod but it takes a dirfd and name instead of a full path.
-func (fs *UnixFS) Chmodat(dirfd int, name string, mode FileMode) error {
-	return fs.fchmodat("chmodat", dirfd, name, mode)
-}
-
-func (fs *UnixFS) fchmodat(op string, dirfd int, name string, mode FileMode) error {
-	return ensurePathError(unix.Fchmodat(dirfd, name, uint32(mode), 0), op, name)
-}
-
-// Chown changes the numeric uid and gid of the named file.
-//
-// If the file is a symbolic link, it changes the uid and gid of the link's target.
-// A uid or gid of -1 means to not change that value.
-// If there is an error, it will be of type *PathError.
-//
-// On Windows or Plan 9, Chown always returns the syscall.EWINDOWS or
-// EPLAN9 error, wrapped in *PathError.
-func (fs *UnixFS) Chown(name string, uid, gid int) error {
-	return ensurePathError(fs.fchown(name, uid, gid, 0), "chown", name)
-}
-
-// Lchown changes the numeric uid and gid of the named file.
-//
-// If the file is a symbolic link, it changes the uid and gid of the link itself.
-// If there is an error, it will be of type *PathError.
-//
-// On Windows, it always returns the syscall.EWINDOWS error, wrapped
-// in *PathError.
-func (fs *UnixFS) Lchown(name string, uid, gid int) error {
-	// With AT_SYMLINK_NOFOLLOW, Fchownat acts like Lchown but allows us to
-	// pass a dirfd.
-	return ensurePathError(fs.fchown(name, uid, gid, AT_SYMLINK_NOFOLLOW), "lchown", name)
-}
-
-// fchown is a re-usable Fchownat syscall used by Chown and Lchown.
-func (fs *UnixFS) fchown(name string, uid, gid, flags int) error {
-	dirfd, name, closeFd, err := fs.safePath(name)
-	defer closeFd()
-	if err != nil {
-		return err
-	}
-	return unix.Fchownat(dirfd, name, uid, gid, flags)
-}
-
-// Chownat is like Chown but allows passing an existing directory file
-// descriptor rather than needing to resolve one.
-func (fs *UnixFS) Chownat(dirfd int, name string, uid, gid int) error {
-	return ensurePathError(unix.Fchownat(dirfd, name, uid, gid, 0), "chownat", name)
-}
-
-// Lchownat is like Lchown but allows passing an existing directory file
-// descriptor rather than needing to resolve one.
-func (fs *UnixFS) Lchownat(dirfd int, name string, uid, gid int) error {
-	return ensurePathError(unix.Fchownat(dirfd, name, uid, gid, AT_SYMLINK_NOFOLLOW), "lchownat", name)
-}
-
-// Chtimes changes the access and modification times of the named
-// file, similar to the Unix utime() or utimes() functions.
-//
-// The underlying filesystem may truncate or round the values to a
-// less precise time unit.
-//
-// If there is an error, it will be of type *PathError.
-func (fs *UnixFS) Chtimes(name string, atime, mtime time.Time) error {
-	dirfd, name, closeFd, err := fs.safePath(name)
-	defer closeFd()
-	if err != nil {
-		return err
-	}
-	return fs.Chtimesat(dirfd, name, atime, mtime)
-}
-
-// Chtimesat is like Chtimes but allows passing an existing directory file
-// descriptor rather than needing to resolve one.
-func (fs *UnixFS) Chtimesat(dirfd int, name string, atime, mtime time.Time) error {
-	var utimes [2]unix.Timespec
-	set := func(i int, t time.Time) {
-		if t.IsZero() {
-			utimes[i] = unix.Timespec{Sec: unix.UTIME_OMIT, Nsec: unix.UTIME_OMIT}
-		} else {
-			utimes[i] = unix.NsecToTimespec(t.UnixNano())
-		}
-	}
-	set(0, atime)
-	set(1, mtime)
-
-	// This does support `AT_SYMLINK_NOFOLLOW` as well if needed.
-	return ensurePathError(unix.UtimesNanoAt(dirfd, name, utimes[0:], 0), "chtimes", name)
-}
-
-// Create creates or truncates the named file. If the file already exists,
-// it is truncated.
-//
-// If the file does not exist, it is created with mode 0666
-// (before umask). If successful, methods on the returned File can
-// be used for I/O; the associated file descriptor has mode O_RDWR.
-// If there is an error, it will be of type *PathError.
-func (fs *UnixFS) Create(name string) (File, error) {
-	return fs.OpenFile(name, O_CREATE|O_WRONLY|O_TRUNC, 0o644)
-}
-
-// Mkdir creates a new directory with the specified name and permission
-// bits (before umask).
-//
-// If there is an error, it will be of type *PathError.
-func (fs *UnixFS) Mkdir(name string, mode FileMode) error {
-	dirfd, name, closeFd, err := fs.safePath(name)
-	defer closeFd()
-	if err != nil {
-		return err
-	}
-	return fs.mkdirat("mkdir", dirfd, name, mode)
-}
-
-func (fs *UnixFS) Mkdirat(dirfd int, name string, mode FileMode) error {
-	return fs.mkdirat("mkdirat", dirfd, name, mode)
-}
-
-func (fs *UnixFS) mkdirat(op string, dirfd int, name string, mode FileMode) error {
-	return ensurePathError(unix.Mkdirat(dirfd, name, uint32(mode)), op, name)
-}
-
-// MkdirAll creates a directory named path, along with any necessary
-// parents, and returns nil, or else returns an error.
-//
-// The permission bits perm (before umask) are used for all
-// directories that MkdirAll creates.
-// If path is already a directory, MkdirAll does nothing
-// and returns nil.
-func (fs *UnixFS) MkdirAll(name string, mode FileMode) error {
-	// Ensure name is somewhat clean before continuing.
-	name, err := fs.unsafePath(name)
-	if err != nil {
-		return err
-	}
-	return fs.mkdirAll(name, mode)
-}
-
-// Open opens the named file for reading.
-//
-// If successful, methods on the returned file can be used for reading; the
-// associated file descriptor has mode O_RDONLY.
-//
-// If there is an error, it will be of type *PathError.
-func (fs *UnixFS) Open(name string) (File, error) {
-	return fs.OpenFile(name, O_RDONLY, 0)
-}
-
-// OpenFile is the generalized open call; most users will use Open
-// or Create instead. It opens the named file with specified flag
-// (O_RDONLY etc.).
-//
-// If the file does not exist, and the O_CREATE flag
-// is passed, it is created with mode perm (before umask). If successful,
-// methods on the returned File can be used for I/O.
-//
-// If there is an error, it will be of type *PathError.
-func (fs *UnixFS) OpenFile(name string, flag int, mode FileMode) (File, error) {
-	fd, err := fs.openFile(name, flag, mode)
-	if err != nil {
-		return nil, err
-	}
-	// Do not close `fd` here, it is passed to a file that needs the fd, the
-	// caller of this function is responsible for calling Close() on the File
-	// to release the file descriptor.
-	return os.NewFile(uintptr(fd), name), nil
-}
-
-func (fs *UnixFS) openFile(name string, flag int, mode FileMode) (int, error) {
-	dirfd, name, closeFd, err := fs.safePath(name)
-	defer closeFd()
-	if err != nil {
-		return 0, err
-	}
-	return fs.openat(dirfd, name, flag, mode)
-}
-
-func (fs *UnixFS) OpenFileat(dirfd int, name string, flag int, mode FileMode) (File, error) {
-	fd, err := fs.openat(dirfd, name, flag, mode)
-	if err != nil {
-		return nil, err
-	}
-	// Do not close `fd` here, it is passed to a file that needs the fd, the
-	// caller of this function is responsible for calling Close() on the File
-	// to release the file descriptor.
-	return os.NewFile(uintptr(fd), name), nil
-}
-
-// ReadDir reads the named directory,
-//
-// returning all its directory entries sorted by filename.
-// If an error occurs reading the directory, ReadDir returns the entries it
-// was able to read before the error, along with the error.
-func (fs *UnixFS) ReadDir(path string) ([]DirEntry, error) {
-	dirfd, name, closeFd, err := fs.safePath(path)
-	defer closeFd()
-	if err != nil {
-		return nil, err
-	}
-	fd, err := fs.openat(dirfd, name, O_DIRECTORY|O_RDONLY, 0)
-	if err != nil {
-		return nil, err
-	}
-	defer func() {
-		_ = unix.Close(fd)
-	}()
-	return fs.readDir(fd, name, ".", nil)
-}
-
-// RemoveStat is a combination of Stat and Remove, it is used to more
-// efficiently remove a file when the caller needs to stat it before
-// removing it.
-//
-// This optimized function exists for our QuotaFS abstraction, which needs
-// to track writes to a filesystem. When removing a file, the QuotaFS needs
-// to know if the entry is a file and if so, how large it is. Because we
-// need to Stat a file in order to get its mode and size, we will already
-// know if the entry needs to be removed by using Unlink or Rmdir. The
-// standard `Remove` method just tries both Unlink and Rmdir (in that order)
-// as it ends up usually being faster and more efficient than calling Stat +
-// the proper operation in the first place.
-func (fs *UnixFS) RemoveStat(name string) (FileInfo, error) {
-	dirfd, name, closeFd, err := fs.safePath(name)
-	defer closeFd()
-	if err != nil {
-		return nil, err
-	}
-
-	// Lstat name, we use Lstat as Unlink doesn't care about symlinks.
-	s, err := fs.Lstatat(dirfd, name)
-	if err != nil {
-		return nil, err
-	}
-
-	if s.IsDir() {
-		err = fs.unlinkat(dirfd, name, AT_REMOVEDIR) // Rmdir
-	} else {
-		err = fs.unlinkat(dirfd, name, 0)
-	}
-	if err != nil {
-		return s, ensurePathError(err, "rename", name)
-	}
-	return s, nil
-}
-
-// Remove removes the named file or (empty) directory.
-//
-// If there is an error, it will be of type *PathError.
-func (fs *UnixFS) Remove(name string) error {
-	dirfd, name, closeFd, err := fs.safePath(name)
-	defer closeFd()
-	if err != nil {
-		return err
-	}
-
-	// Prevent trying to Remove the base directory.
-	if name == "." {
-		return &PathError{
-			Op:   "remove",
-			Path: name,
-			Err:  ErrBadPathResolution,
-		}
-	}
-
-	// System call interface forces us to know
-	// whether name is a file or directory.
-	// Try both: it is cheaper on average than
-	// doing a Stat plus the right one.
-	err = fs.unlinkat(dirfd, name, 0)
-	if err == nil {
-		return nil
-	}
-	err1 := fs.unlinkat(dirfd, name, AT_REMOVEDIR) // Rmdir
-	if err1 == nil {
-		return nil
-	}
-
-	// Both failed: figure out which error to return.
-	// OS X and Linux differ on whether unlink(dir)
-	// returns EISDIR, so can't use that. However,
-	// both agree that rmdir(file) returns ENOTDIR,
-	// so we can use that to decide which error is real.
-	// Rmdir might also return ENOTDIR if given a bad
-	// file path, like /etc/passwd/foo, but in that case,
-	// both errors will be ENOTDIR, so it's okay to
-	// use the error from unlink.
-	if err1 != unix.ENOTDIR {
-		err = err1
-	}
-	return ensurePathError(err, "remove", name)
-}
-
-// RemoveAll removes path and any children it contains.
-//
-// It removes everything it can but returns the first error
-// it encounters. If the path does not exist, RemoveAll
-// returns nil (no error).
-//
-// If there is an error, it will be of type *PathError.
-func (fs *UnixFS) RemoveAll(name string) error {
-	name, err := fs.unsafePath(name)
-	if err != nil {
-		return err
-	}
-
-	// While removeAll internally checks this, I want to make sure we check it
-	// and return the proper error so our tests can ensure that this will never
-	// be a possibility.
-	if name == "." {
-		return &PathError{
-			Op:   "removeall",
-			Path: name,
-			Err:  ErrBadPathResolution,
-		}
-	}
-
-	return fs.removeAll(name)
-}
-
-// RemoveContents recursively removes the contents of name.
-//
-// It removes everything it can but returns the first error
-// it encounters. If the path does not exist, RemoveContents
-// returns nil (no error).
-//
-// If there is an error, it will be of type [*PathError].
-func (fs *UnixFS) RemoveContents(name string) error {
-	name, err := fs.unsafePath(name)
-	if err != nil {
-		return err
-	}
-
-	// Unlike RemoveAll, we don't remove `name` itself, only it's contents.
-	// So there is no need to check for a name of `.` here.
-
-	return fs.removeContents(name)
-}
-
-func (fs *UnixFS) unlinkat(dirfd int, name string, flags int) error {
-	return ignoringEINTR(func() error {
-		return unix.Unlinkat(dirfd, name, flags)
-	})
-}
-
-// Rename renames (moves) oldpath to newpath.
-//
-// If newpath already exists and is not a directory, Rename replaces it.
-// OS-specific restrictions may apply when oldpath and newpath are in different directories.
-// Even within the same directory, on non-Unix platforms Rename is not an atomic operation.
-//
-// If there is an error, it will be of type *LinkError.
-func (fs *UnixFS) Rename(oldpath, newpath string) error {
-	// Simple case: both paths are the same.
-	if oldpath == newpath {
-		return nil
-	}
-
-	olddirfd, oldname, closeFd, err := fs.safePath(oldpath)
-	defer closeFd()
-	if err != nil {
-		return err
-	}
-	// Ensure that we are not trying to rename the base directory itself.
-	// While unix.Renameat ends up throwing a "device or resource busy" error,
-	// that doesn't mean we are protecting the system properly.
-	if oldname == "." {
-		return &PathError{
-			Op:   "rename",
-			Path: oldname,
-			Err:  ErrBadPathResolution,
-		}
-	}
-	// Stat the old target to return proper errors.
-	if _, err := fs.Lstatat(olddirfd, oldname); err != nil {
-		return err
-	}
-
-	newdirfd, newname, closeFd2, err := fs.safePath(newpath)
-	if err != nil {
-		closeFd2()
-		if !errors.Is(err, ErrNotExist) {
-			return err
-		}
-		var pathErr *PathError
-		if !errors.As(err, &pathErr) {
-			return err
-		}
-		if err := fs.MkdirAll(pathErr.Path, 0o755); err != nil {
-			return err
-		}
-		newdirfd, newname, closeFd2, err = fs.safePath(newpath)
-		defer closeFd2()
-		if err != nil {
-			return err
-		}
-	} else {
-		defer closeFd2()
-	}
-
-	// Ensure that we are not trying to rename the base directory itself.
-	// While unix.Renameat ends up throwing a "device or resource busy" error,
-	// that doesn't mean we are protecting the system properly.
-	if newname == "." {
-		return &PathError{
-			Op:   "rename",
-			Path: newname,
-			Err:  ErrBadPathResolution,
-		}
-	}
-	// Stat the new target to return proper errors.
-	_, err = fs.Lstatat(newdirfd, newname)
-	switch {
-	case err == nil:
-		return &PathError{
-			Op:   "rename",
-			Path: newname,
-			Err:  ErrExist,
-		}
-	case !errors.Is(err, ErrNotExist):
-		return err
-	}
-	if err := unix.Renameat(olddirfd, oldname, newdirfd, newname); err != nil {
-		return &LinkError{Op: "rename", Old: oldpath, New: newpath, Err: err}
-	}
-	return nil
-}
-
-// Stat returns a FileInfo describing the named file.
-//
-// If there is an error, it will be of type *PathError.
-func (fs *UnixFS) Stat(name string) (FileInfo, error) {
-	return fs._fstat("stat", name, 0)
-}
-
-// Statat is like Stat but allows passing an existing directory file
-// descriptor rather than needing to resolve one.
-func (fs *UnixFS) Statat(dirfd int, name string) (FileInfo, error) {
-	return fs._fstatat("statat", dirfd, name, 0)
-}
-
-// Lstat returns a FileInfo describing the named file.
-//
-// If the file is a symbolic link, the returned FileInfo
-// describes the symbolic link. Lstat makes no attempt to follow the link.
-//
-// If there is an error, it will be of type *PathError.
-func (fs *UnixFS) Lstat(name string) (FileInfo, error) {
-	return fs._fstat("lstat", name, AT_SYMLINK_NOFOLLOW)
-}
-
-// Lstatat is like Lstat but allows passing an existing directory file
-// descriptor rather than needing to resolve one.
-func (fs *UnixFS) Lstatat(dirfd int, name string) (FileInfo, error) {
-	return fs._fstatat("lstatat", dirfd, name, AT_SYMLINK_NOFOLLOW)
-}
-
-func (fs *UnixFS) fstat(name string, flags int) (FileInfo, error) {
-	return fs._fstat("fstat", name, flags)
-}
-
-func (fs *UnixFS) _fstat(op string, name string, flags int) (FileInfo, error) {
-	dirfd, name, closeFd, err := fs.safePath(name)
-	defer closeFd()
-	if err != nil {
-		return nil, err
-	}
-	return fs._fstatat(op, dirfd, name, flags)
-}
-
-func (fs *UnixFS) fstatat(dirfd int, name string, flags int) (FileInfo, error) {
-	return fs._fstatat("fstatat", dirfd, name, flags)
-}
-
-func (fs *UnixFS) _fstatat(op string, dirfd int, name string, flags int) (FileInfo, error) {
-	var s fileStat
-	if err := ignoringEINTR(func() error {
-		return unix.Fstatat(dirfd, name, &s.sys, flags)
-	}); err != nil {
-		return nil, ensurePathError(err, op, name)
-	}
-	fillFileStatFromSys(&s, name)
-	return &s, nil
-}
-
-// Symlink creates newname as a symbolic link to oldname.
-//
-// On Windows, a symlink to a non-existent oldname creates a file symlink;
-// if oldname is later created as a directory the symlink will not work.
-//
-// If there is an error, it will be of type *LinkError.
-func (fs *UnixFS) Symlink(oldpath, newpath string) error {
-	dirfd, newpath, closeFd, err := fs.safePath(newpath)
-	defer closeFd()
-	if err != nil {
-		return err
-	}
-	if err := ignoringEINTR(func() error {
-		// We aren't concerned with oldpath here as a symlink can point anywhere
-		// it wants.
-		return unix.Symlinkat(oldpath, dirfd, newpath)
-	}); err != nil {
-		return &LinkError{Op: "symlink", Old: oldpath, New: newpath, Err: err}
-	}
-	return nil
-}
-
-// Touch will attempt to open a file for reading and/or writing. If the file
-// does not exist it will be created, and any missing parent directories will
-// also be created. The opened file may be truncated, only if `flag` has
-// O_TRUNC set.
-func (fs *UnixFS) Touch(path string, flag int, mode FileMode) (File, error) {
-	if flag&O_CREATE == 0 {
-		flag |= O_CREATE
-	}
-	dirfd, name, closeFd, err, _ := fs.TouchPath(path)
-	defer closeFd()
-	if err != nil {
-		return nil, err
-	}
-	return fs.OpenFileat(dirfd, name, flag, mode)
-}
-
-// TouchPath is like SafePath except that it will create any missing directories
-// in the path. Unlike SafePath, TouchPath returns an additional boolean which
-// indicates whether the parent directories already existed, this is intended to
-// be used as a way to know if the final destination could already exist.
-func (fs *UnixFS) TouchPath(path string) (int, string, func(), error, bool) {
-	dirfd, name, closeFd, err := fs.safePath(path)
-	switch {
-	case err == nil:
-		return dirfd, name, closeFd, nil, true
-	case !errors.Is(err, ErrNotExist):
-		return dirfd, name, closeFd, err, false
-	}
-
-	var pathErr *PathError
-	if !errors.As(err, &pathErr) {
-		return dirfd, name, closeFd, err, false
-	}
-	if err := fs.MkdirAll(pathErr.Path, 0o755); err != nil {
-		return dirfd, name, closeFd, err, false
-	}
-
-	// Close the previous file descriptor since we are going to be opening
-	// a new one.
-	closeFd()
-
-	// Run safe path again now that the parent directories have been created.
-	dirfd, name, closeFd, err = fs.safePath(path)
-	return dirfd, name, closeFd, err, false
-}
-
-// WalkDir walks the file tree rooted at root, calling fn for each file or
-// directory in the tree, including root.
-//
-// All errors that arise visiting files and directories are filtered by fn:
-// see the [WalkDirFunc] documentation for details.
-//
-// The files are walked in lexical order, which makes the output deterministic
-// but requires WalkDir to read an entire directory into memory before proceeding
-// to walk that directory.
-//
-// WalkDir does not follow symbolic links found in directories,
-// but if root itself is a symbolic link, its target will be walked.
-func (fs *UnixFS) WalkDir(root string, fn WalkDirFunc) error {
-	return WalkDir(fs, root, fn)
-}
-
-// openat is a wrapper around both unix.Openat and unix.Openat2. If the UnixFS
-// was configured to enable openat2 support, unix.Openat2 will be used instead
-// of unix.Openat due to having better security properties for our use-case.
-func (fs *UnixFS) openat(dirfd int, name string, flag int, mode FileMode) (int, error) {
-	if flag&O_NOFOLLOW == 0 {
-		flag |= O_NOFOLLOW
-	}
-
-	var fd int
-	for {
-		var err error
-		if fs.useOpenat2 {
-			fd, err = fs._openat2(dirfd, name, uint64(flag), uint64(syscallMode(mode)))
-		} else {
-			fd, err = fs._openat(dirfd, name, flag, uint32(syscallMode(mode)))
-		}
-		if err == nil {
-			break
-		}
-		// We have to check EINTR here, per issues https://go.dev/issue/11180 and https://go.dev/issue/39237.
-		if err == unix.EINTR {
-			continue
-		}
-		return 0, err
-	}
-
-	// If we are using openat2, we don't need the additional security checks.
-	if fs.useOpenat2 {
-		return fd, nil
-	}
-
-	// If we are not using openat2, do additional path checking. This assumes
-	// that openat2 is using `RESOLVE_BENEATH` to avoid the same security
-	// issue.
-	var finalPath string
-	finalPath, err := filepath.EvalSymlinks(filepath.Join("/proc/self/fd/", strconv.Itoa(fd)))
-	if err != nil {
-		if !errors.Is(err, ErrNotExist) {
-			return fd, fmt.Errorf("failed to evaluate symlink: %w", convertErrorType(err))
-		}
-
-		// The target of one of the symlinks (EvalSymlinks is recursive)
-		// does not exist. So get the path that does not exist and use
-		// that for further validation instead.
-		var pErr *PathError
-		if !errors.As(err, &pErr) {
-			return fd, fmt.Errorf("failed to evaluate symlink: %w", convertErrorType(err))
-		}
-
-		// Update the final path to whatever directory or path didn't exist while
-		// recursing any symlinks.
-		finalPath = pErr.Path
-		// Ensure the error is wrapped correctly.
-		err = convertErrorType(err)
-	}
-
-	// Check if the path is within our root.
-	if !fs.unsafeIsPathInsideOfBase(finalPath) {
-		op := "openat"
-		if fs.useOpenat2 {
-			op = "openat2"
-		}
-		return fd, &PathError{
-			Op:   op,
-			Path: name,
-			Err:  ErrBadPathResolution,
-		}
-	}
-
-	// Return the file descriptor and any potential error.
-	return fd, err
-}
-
-// _openat is a wrapper around unix.Openat. This method should never be directly
-// called, use `openat` instead.
-func (fs *UnixFS) _openat(dirfd int, name string, flag int, mode uint32) (int, error) {
-	// Ensure the O_CLOEXEC flag is set.
-	// Go sets this in the os package, but since we are directly using unix
-	// we need to set it ourselves.
-	if flag&O_CLOEXEC == 0 {
-		flag |= O_CLOEXEC
-	}
-	// O_LARGEFILE is set by Openat for us automatically.
-	fd, err := unix.Openat(dirfd, name, flag, mode)
-	switch {
-	case err == nil:
-		return fd, nil
-	case err == unix.EINTR:
-		return fd, err
-	case err == unix.EAGAIN:
-		return fd, err
-	default:
-		return fd, ensurePathError(err, "openat", name)
-	}
-}
-
-// _openat2 is a wonderful syscall that supersedes the `openat` syscall. It has
-// improved validation and security characteristics that weren't available or
-// considered when `openat` was originally implemented. As such, it is only
-// present in Kernel 5.6 and above.
-//
-// This method should never be directly called, use `openat` instead.
-func (fs *UnixFS) _openat2(dirfd int, name string, flag, mode uint64) (int, error) {
-	// Ensure the O_CLOEXEC flag is set.
-	// Go sets this when using the os package, but since we are directly using
-	// the unix package we need to set it ourselves.
-	if flag&O_CLOEXEC == 0 {
-		flag |= O_CLOEXEC
-	}
-	// Ensure the O_LARGEFILE flag is set.
-	// Go sets this for unix.Open, unix.Openat, but not unix.Openat2.
-	if flag&O_LARGEFILE == 0 {
-		flag |= O_LARGEFILE
-	}
-	fd, err := unix.Openat2(dirfd, name, &unix.OpenHow{
-		Flags: flag,
-		Mode:  mode,
-		// This is the bread and butter of preventing a symlink escape, without
-		// this option, we have to handle path validation fully on our own.
-		//
-		// This is why using Openat2 over Openat is preferred if available.
-		Resolve: unix.RESOLVE_BENEATH,
-	})
-	switch {
-	case err == nil:
-		return fd, nil
-	case err == unix.EINTR:
-		return fd, err
-	case err == unix.EAGAIN:
-		return fd, err
-	default:
-		return fd, ensurePathError(err, "openat2", name)
-	}
-}
-
-func (fs *UnixFS) SafePath(path string) (int, string, func(), error) {
-	return fs.safePath(path)
-}
-
-func (fs *UnixFS) safePath(path string) (dirfd int, file string, closeFd func(), err error) {
-	// Default closeFd to a NO-OP.
-	closeFd = func() {}
-
-	// Use unsafePath to clean the path and strip BasePath if path is absolute.
-	var name string
-	name, err = fs.unsafePath(path)
-	if err != nil {
-		return
-	}
-
-	// Open the base path. We use this as the sandbox root for any further
-	// operations.
-	var fsDirfd int
-	fsDirfd, err = fs._openat(AT_EMPTY_PATH, fs.basePath, O_DIRECTORY|O_RDONLY, 0)
-	if err != nil {
-		return
-	}
-
-	// Split the parent from the last element in the path, this gives us the
-	// "file name" and the full path to its parent.
-	var dir string
-	dir, file = filepath.Split(name)
-	// If dir is empty then name is not nested.
-	if dir == "" {
-		dirfd = fsDirfd
-		closeFd = func() { _ = unix.Close(dirfd) }
-
-		// Return dirfd, name, an empty closeFd func, and no error
-		return
-	}
-
-	// Dir will usually contain a trailing slash as filepath.Split doesn't
-	// trim slashes.
-	dir = strings.TrimSuffix(dir, "/")
-	dirfd, err = fs.openat(fsDirfd, dir, O_DIRECTORY|O_RDONLY, 0)
-	if err != nil {
-		// An error occurred while opening the directory, but we already opened
-		// the filesystem root, so we still need to ensure it gets closed.
-		closeFd = func() { _ = unix.Close(fsDirfd) }
-	} else {
-		// Set closeFd to close the newly opened directory file descriptor.
-		closeFd = func() {
-			_ = unix.Close(dirfd)
-			_ = unix.Close(fsDirfd)
-		}
-	}
-
-	// Return dirfd, name, the closeFd func, and err
-	return
-}
-
-// unsafePath strips and joins the given path with the filesystem's base path,
-// cleaning the result. The cleaned path is then checked if it starts with the
-// filesystem's base path to obvious any obvious path traversal escapes. The
-// fully resolved path (if symlinks are followed) may not be within the
-// filesystem's base path, additional checks are required to safely use paths
-// returned by this function.
-func (fs *UnixFS) unsafePath(path string) (string, error) {
-	// Calling filepath.Clean on the path will resolve it to it's absolute path,
-	// removing any path traversal arguments (such as ..), leaving us with an
-	// absolute path we can then use.
-	//
-	// This will also trim the filesystem's base path from the given path and
-	// join the base path back on to ensure the path starts with the base path
-	// without appending it twice.
-	r := filepath.Clean(filepath.Join(fs.basePath, strings.TrimPrefix(path, fs.basePath)))
-
-	if fs.unsafeIsPathInsideOfBase(r) {
-		// This is kinda ironic isn't it.
-		// We do this as we are operating with dirfds and `*at` syscalls which
-		// behave differently if given an absolute path.
-		//
-		// First trim the BasePath, then trim any leading slashes.
-		r = strings.TrimPrefix(strings.TrimPrefix(r, fs.basePath), "/")
-		// If the path is empty then return "." as the path is pointing to the
-		// root.
-		if r == "" {
-			return ".", nil
-		}
-		return r, nil
-	}
-
-	return "", &PathError{
-		Op:   "safePath",
-		Path: path,
-		Err:  ErrBadPathResolution,
-	}
-}
-
-// unsafeIsPathInsideOfBase checks if the given path is inside the filesystem's
-// base path.
-//
-// NOTE: this method doesn't clean the given path or attempt to join the
-// filesystem's base path. This is purely a basic prefix check against the
-// given path.
-func (fs *UnixFS) unsafeIsPathInsideOfBase(path string) bool {
-	return strings.HasPrefix(
-		strings.TrimSuffix(path, "/")+"/",
-		fs.basePath+"/",
-	)
-}

internal/ufs/fs_unix_test.go

@@ -1,768 +0,0 @@
-// SPDX-License-Identifier: MIT
-// SPDX-FileCopyrightText: Copyright (c) 2024 Matthew Penner
-
-//go:build unix
-
-package ufs_test
-
-import (
-	"errors"
-	"os"
-	"path/filepath"
-	"reflect"
-	"slices"
-	"strconv"
-	"testing"
-
-	"github.com/pterodactyl/wings/internal/ufs"
-)
-
-type testUnixFS struct {
-	*ufs.UnixFS
-
-	TmpDir string
-	Root   string
-}
-
-func (fs *testUnixFS) Cleanup() {
-	_ = fs.Close()
-	_ = os.RemoveAll(fs.TmpDir)
-}
-
-func newTestUnixFS() (*testUnixFS, error) {
-	tmpDir, err := os.MkdirTemp(os.TempDir(), "ufs")
-	if err != nil {
-		return nil, err
-	}
-	root := filepath.Join(tmpDir, "root")
-	if err := os.Mkdir(root, 0o755); err != nil {
-		return nil, err
-	}
-	// fmt.Println(tmpDir)
-	fs, err := ufs.NewUnixFS(root, true)
-	if err != nil {
-		return nil, err
-	}
-	tfs := &testUnixFS{
-		UnixFS: fs,
-		TmpDir: tmpDir,
-		Root:   root,
-	}
-	return tfs, nil
-}
-
-func TestUnixFS(t *testing.T) {
-	t.Parallel()
-
-	fs, err := newTestUnixFS()
-	if err != nil {
-		t.Fatal(err)
-		return
-	}
-	defer fs.Cleanup()
-
-	// Test creating a file within the root.
-	_, _, closeFd, err := fs.SafePath("/")
-	closeFd()
-	if err != nil {
-		t.Error(err)
-		return
-	}
-
-	f, err := fs.Touch("directory/file", ufs.O_RDWR, 0o644)
-	if err != nil {
-		t.Error(err)
-		return
-	}
-	_ = f.Close()
-
-	// Test creating a file within the root.
-	f, err = fs.Create("test")
-	if err != nil {
-		t.Error(err)
-		return
-	}
-	_ = f.Close()
-
-	// Test stating a file within the root.
-	if _, err := fs.Stat("test"); err != nil {
-		t.Error(err)
-		return
-	}
-
-	// Test creating a directory within the root.
-	if err := fs.Mkdir("ima_directory", 0o755); err != nil {
-		t.Error(err)
-		return
-	}
-
-	// Test creating a nested directory within the root.
-	if err := fs.Mkdir("ima_directory/ima_nother_directory", 0o755); err != nil {
-		t.Error(err)
-		return
-	}
-
-	// Test creating a file inside a directory within the root.
-	f, err = fs.Create("ima_directory/ima_file")
-	if err != nil {
-		t.Error(err)
-		return
-	}
-	_ = f.Close()
-
-	// Test listing directory entries.
-	if _, err := fs.ReadDir("ima_directory"); err != nil {
-		t.Error(err)
-		return
-	}
-
-	// Test symlink pointing outside the root.
-	if err := os.Symlink(fs.TmpDir, filepath.Join(fs.Root, "ima_bad_link")); err != nil {
-		t.Error(err)
-		return
-	}
-	f, err = fs.Create("ima_bad_link/ima_bad_file")
-	if err == nil {
-		_ = f.Close()
-		t.Error("expected an error")
-		return
-	}
-	if err := fs.Mkdir("ima_bad_link/ima_bad_directory", 0o755); err == nil {
-		t.Error("expected an error")
-		return
-	}
-
-	// Test symlink pointing outside the root inside a parent directory.
-	if err := fs.Symlink(fs.TmpDir, filepath.Join(fs.Root, "ima_directory/ima_bad_link")); err != nil {
-		t.Error(err)
-		return
-	}
-	if err := fs.Mkdir("ima_directory/ima_bad_link/ima_bad_directory", 0o755); err == nil {
-		t.Error("expected an error")
-		return
-	}
-
-	// Test symlink pointing outside the root with a child directory.
-	if err := os.Mkdir(filepath.Join(fs.TmpDir, "ima_directory"), 0o755); err != nil {
-		t.Error(err)
-		return
-	}
-	f, err = fs.Create("ima_bad_link/ima_directory/ima_bad_file")
-	if err == nil {
-		_ = f.Close()
-		t.Error("expected an error")
-		return
-	}
-	if err := fs.Mkdir("ima_bad_link/ima_directory/ima_bad_directory", 0o755); err == nil {
-		t.Error("expected an error")
-		return
-	}
-
-	if _, err := fs.ReadDir("ima_bad_link/ima_directory"); err == nil {
-		t.Error("expected an error")
-		return
-	}
-
-	// Create multiple nested directories.
-	if err := fs.MkdirAll("ima_directory/ima_directory/ima_directory/ima_directory", 0o755); err != nil {
-		t.Error(err)
-		return
-	}
-	if _, err := fs.ReadDir("ima_directory/ima_directory"); err != nil {
-		t.Error(err)
-		return
-	}
-
-	// Test creating a directory under a symlink with a pre-existing directory.
-	if err := fs.MkdirAll("ima_bad_link/ima_directory/ima_bad_directory/ima_bad_directory", 0o755); err == nil {
-		t.Error("expected an error")
-		return
-	}
-
-	// Test deletion
-	if err := fs.Remove("test"); err != nil {
-		t.Error(err)
-		return
-	}
-	if err := fs.Remove("ima_bad_link"); err != nil {
-		t.Error(err)
-		return
-	}
-
-	// Test recursive deletion
-	if err := fs.RemoveAll("ima_directory"); err != nil {
-		t.Error(err)
-		return
-	}
-
-	// Test recursive deletion underneath a bad symlink
-	if err := fs.Mkdir("ima_directory", 0o755); err != nil {
-		t.Error(err)
-		return
-	}
-	if err := fs.Symlink(fs.TmpDir, filepath.Join(fs.Root, "ima_directory/ima_bad_link")); err != nil {
-		t.Error(err)
-		return
-	}
-	if err := fs.RemoveAll("ima_directory/ima_bad_link/ima_bad_file"); err == nil {
-		t.Error("expected an error")
-		return
-	}
-
-	// This should delete the symlink itself.
-	if err := fs.RemoveAll("ima_directory/ima_bad_link"); err != nil {
-		t.Error(err)
-		return
-	}
-
-	//for i := 0; i < 5; i++ {
-	//	dirName := "dir" + strconv.Itoa(i)
-	//	if err := fs.Mkdir(dirName, 0o755); err != nil {
-	//		t.Error(err)
-	//		return
-	//	}
-	//	for j := 0; j < 5; j++ {
-	//		f, err := fs.Create(filepath.Join(dirName, "file"+strconv.Itoa(j)))
-	//		if err != nil {
-	//			t.Error(err)
-	//			return
-	//		}
-	//		_ = f.Close()
-	//	}
-	//}
-	//
-	//if err := fs.WalkDir2("", func(fd int, path string, info filesystem.DirEntry, err error) error {
-	//	if err != nil {
-	//		return err
-	//	}
-	//	fmt.Println(path)
-	//	return nil
-	//}); err != nil {
-	//	t.Error(err)
-	//	return
-	//}
-}
-
-func TestUnixFS_Chmod(t *testing.T) {
-	t.Parallel()
-	fs, err := newTestUnixFS()
-	if err != nil {
-		t.Fatal(err)
-		return
-	}
-	defer fs.Cleanup()
-
-	// TODO: implement
-}
-
-func TestUnixFS_Chown(t *testing.T) {
-	t.Parallel()
-	fs, err := newTestUnixFS()
-	if err != nil {
-		t.Fatal(err)
-		return
-	}
-	defer fs.Cleanup()
-
-	// TODO: implement
-}
-
-func TestUnixFS_Lchown(t *testing.T) {
-	t.Parallel()
-	fs, err := newTestUnixFS()
-	if err != nil {
-		t.Fatal(err)
-		return
-	}
-	defer fs.Cleanup()
-
-	// TODO: implement
-}
-
-func TestUnixFS_Chtimes(t *testing.T) {
-	t.Parallel()
-	fs, err := newTestUnixFS()
-	if err != nil {
-		t.Fatal(err)
-		return
-	}
-	defer fs.Cleanup()
-
-	// TODO: implement
-}
-
-func TestUnixFS_Create(t *testing.T) {
-	t.Parallel()
-	fs, err := newTestUnixFS()
-	if err != nil {
-		t.Fatal(err)
-		return
-	}
-	defer fs.Cleanup()
-
-	// TODO: implement
-}
-
-func TestUnixFS_Mkdir(t *testing.T) {
-	t.Parallel()
-	fs, err := newTestUnixFS()
-	if err != nil {
-		t.Fatal(err)
-		return
-	}
-	defer fs.Cleanup()
-
-	// TODO: implement
-}
-
-func TestUnixFS_MkdirAll(t *testing.T) {
-	t.Parallel()
-	fs, err := newTestUnixFS()
-	if err != nil {
-		t.Fatal(err)
-		return
-	}
-	defer fs.Cleanup()
-
-	if err := fs.MkdirAll("/a/bunch/of/directories", 0o755); err != nil {
-		t.Error(err)
-		return
-	}
-
-	// TODO: stat sanity check
-}
-
-func TestUnixFS_Open(t *testing.T) {
-	t.Parallel()
-	fs, err := newTestUnixFS()
-	if err != nil {
-		t.Fatal(err)
-		return
-	}
-	defer fs.Cleanup()
-
-	// TODO: implement
-}
-
-func TestUnixFS_OpenFile(t *testing.T) {
-	t.Parallel()
-	fs, err := newTestUnixFS()
-	if err != nil {
-		t.Fatal(err)
-		return
-	}
-	defer fs.Cleanup()
-
-	// TODO: implement
-}
-
-func TestUnixFS_ReadDir(t *testing.T) {
-	t.Parallel()
-	fs, err := newTestUnixFS()
-	if err != nil {
-		t.Fatal(err)
-		return
-	}
-	defer fs.Cleanup()
-
-	// TODO: implement
-}
-
-func TestUnixFS_Remove(t *testing.T) {
-	t.Parallel()
-	fs, err := newTestUnixFS()
-	if err != nil {
-		t.Fatal(err)
-		return
-	}
-	defer fs.Cleanup()
-
-	t.Run("base directory", func(t *testing.T) {
-		// Try to remove the base directory.
-		if err := fs.Remove(""); !errors.Is(err, ufs.ErrBadPathResolution) {
-			t.Errorf("expected an a bad path resolution error, but got: %v", err)
-			return
-		}
-	})
-
-	t.Run("path traversal", func(t *testing.T) {
-		// Try to remove the base directory.
-		if err := fs.RemoveAll("../root"); !errors.Is(err, ufs.ErrBadPathResolution) {
-			t.Errorf("expected an a bad path resolution error, but got: %v", err)
-			return
-		}
-	})
-}
-
-func TestUnixFS_RemoveAll(t *testing.T) {
-	t.Parallel()
-	fs, err := newTestUnixFS()
-	if err != nil {
-		t.Fatal(err)
-		return
-	}
-	defer fs.Cleanup()
-
-	t.Run("base directory", func(t *testing.T) {
-		// Try to remove the base directory.
-		if err := fs.RemoveAll(""); !errors.Is(err, ufs.ErrBadPathResolution) {
-			t.Errorf("expected an a bad path resolution error, but got: %v", err)
-			return
-		}
-	})
-
-	t.Run("path traversal", func(t *testing.T) {
-		// Try to remove the base directory.
-		if err := fs.RemoveAll("../root"); !errors.Is(err, ufs.ErrBadPathResolution) {
-			t.Errorf("expected an a bad path resolution error, but got: %v", err)
-			return
-		}
-	})
-}
-
-func TestUnixFS_Rename(t *testing.T) {
-	t.Parallel()
-	fs, err := newTestUnixFS()
-	if err != nil {
-		t.Fatal(err)
-		return
-	}
-	defer fs.Cleanup()
-
-	t.Run("rename base directory", func(t *testing.T) {
-		// Try to rename the base directory.
-		if err := fs.Rename("", "yeet"); !errors.Is(err, ufs.ErrBadPathResolution) {
-			t.Errorf("expected an a bad path resolution error, but got: %v", err)
-			return
-		}
-	})
-
-	t.Run("rename over base directory", func(t *testing.T) {
-		// Create a directory that we are going to try and move over top of the
-		// existing base directory.
-		if err := fs.Mkdir("overwrite_dir", 0o755); err != nil {
-			t.Error(err)
-			return
-		}
-
-		// Try to rename over the base directory.
-		if err := fs.Rename("overwrite_dir", ""); !errors.Is(err, ufs.ErrBadPathResolution) {
-			t.Errorf("expected an a bad path resolution error, but got: %v", err)
-			return
-		}
-	})
-
-	t.Run("directory rename", func(t *testing.T) {
-		// Create a directory to rename to something else.
-		if err := fs.Mkdir("test_directory", 0o755); err != nil {
-			t.Error(err)
-			return
-		}
-
-		// Try to rename "test_directory" to "directory".
-		if err := fs.Rename("test_directory", "directory"); err != nil {
-			t.Errorf("expected no error, but got: %v", err)
-			return
-		}
-
-		// Sanity check
-		if _, err := os.Lstat(filepath.Join(fs.Root, "directory")); err != nil {
-			t.Errorf("Lstat errored when performing sanity check: %v", err)
-			return
-		}
-	})
-
-	t.Run("file rename", func(t *testing.T) {
-		// Create a directory to rename to something else.
-		f, err := fs.Create("test_file")
-		if err != nil {
-			t.Error(err)
-			return
-		}
-		_ = f.Close()
-
-		// Try to rename "test_file" to "file".
-		if err := fs.Rename("test_file", "file"); err != nil {
-			t.Errorf("expected no error, but got: %v", err)
-			return
-		}
-
-		// Sanity check
-		if _, err := os.Lstat(filepath.Join(fs.Root, "file")); err != nil {
-			t.Errorf("Lstat errored when performing sanity check: %v", err)
-			return
-		}
-	})
-}
-
-func TestUnixFS_Stat(t *testing.T) {
-	t.Parallel()
-	fs, err := newTestUnixFS()
-	if err != nil {
-		t.Fatal(err)
-		return
-	}
-	defer fs.Cleanup()
-
-	// TODO: implement
-}
-
-func TestUnixFS_Lstat(t *testing.T) {
-	t.Parallel()
-	fs, err := newTestUnixFS()
-	if err != nil {
-		t.Fatal(err)
-		return
-	}
-	defer fs.Cleanup()
-
-	// TODO: implement
-}
-
-func TestUnixFS_Symlink(t *testing.T) {
-	t.Parallel()
-	fs, err := newTestUnixFS()
-	if err != nil {
-		t.Fatal(err)
-		return
-	}
-	defer fs.Cleanup()
-
-	// TODO: implement
-}
-
-func TestUnixFS_Touch(t *testing.T) {
-	t.Parallel()
-	fs, err := newTestUnixFS()
-	if err != nil {
-		t.Fatal(err)
-		return
-	}
-	defer fs.Cleanup()
-
-	t.Run("base directory", func(t *testing.T) {
-		path := "i_touched_a_file"
-		f, err := fs.Touch(path, ufs.O_RDWR, 0o644)
-		if err != nil {
-			t.Error(err)
-			return
-		}
-		_ = f.Close()
-
-		// Sanity check
-		if _, err := os.Lstat(filepath.Join(fs.Root, path)); err != nil {
-			t.Errorf("Lstat errored when performing sanity check: %v", err)
-			return
-		}
-	})
-
-	t.Run("existing parent directory", func(t *testing.T) {
-		dir := "some_parent_directory"
-		if err := fs.Mkdir(dir, 0o755); err != nil {
-			t.Errorf("error creating parent directory: %v", err)
-			return
-		}
-		path := filepath.Join(dir, "i_touched_a_file")
-		f, err := fs.Touch(path, ufs.O_RDWR, 0o644)
-		if err != nil {
-			t.Errorf("error touching file: %v", err)
-			return
-		}
-		_ = f.Close()
-
-		// Sanity check
-		if _, err := os.Lstat(filepath.Join(fs.Root, path)); err != nil {
-			t.Errorf("Lstat errored when performing sanity check: %v", err)
-			return
-		}
-	})
-
-	t.Run("non-existent parent directory", func(t *testing.T) {
-		path := "some_other_directory/i_touched_a_file"
-		f, err := fs.Touch(path, ufs.O_RDWR, 0o644)
-		if err != nil {
-			t.Errorf("error touching file: %v", err)
-			return
-		}
-		_ = f.Close()
-
-		// Sanity check
-		if _, err := os.Lstat(filepath.Join(fs.Root, path)); err != nil {
-			t.Errorf("Lstat errored when performing sanity check: %v", err)
-			return
-		}
-	})
-
-	t.Run("non-existent parent directories", func(t *testing.T) {
-		path := "some_other_directory/some_directory/i_touched_a_file"
-		f, err := fs.Touch(path, ufs.O_RDWR, 0o644)
-		if err != nil {
-			t.Errorf("error touching file: %v", err)
-			return
-		}
-		_ = f.Close()
-
-		// Sanity check
-		if _, err := os.Lstat(filepath.Join(fs.Root, path)); err != nil {
-			t.Errorf("Lstat errored when performing sanity check: %v", err)
-			return
-		}
-	})
-}
-
-func TestUnixFS_WalkDir(t *testing.T) {
-	t.Parallel()
-	fs, err := newTestUnixFS()
-	if err != nil {
-		t.Fatal(err)
-		return
-	}
-	defer fs.Cleanup()
-
-	//for i := 0; i < 5; i++ {
-	//	dirName := "dir" + strconv.Itoa(i)
-	//	if err := fs.Mkdir(dirName, 0o755); err != nil {
-	//		t.Error(err)
-	//		return
-	//	}
-	//	for j := 0; j < 5; j++ {
-	//		f, err := fs.Create(filepath.Join(dirName, "file"+strconv.Itoa(j)))
-	//		if err != nil {
-	//			t.Error(err)
-	//			return
-	//		}
-	//		_ = f.Close()
-	//	}
-	//}
-	//
-	//if err := fs.WalkDir(".", func(path string, info ufs.DirEntry, err error) error {
-	//	if err != nil {
-	//		return err
-	//	}
-	//	t.Log(path)
-	//	return nil
-	//}); err != nil {
-	//	t.Error(err)
-	//	return
-	//}
-}
-
-func TestUnixFS_WalkDirat(t *testing.T) {
-	t.Parallel()
-	fs, err := newTestUnixFS()
-	if err != nil {
-		t.Fatal(err)
-		return
-	}
-	defer fs.Cleanup()
-
-	for i := 0; i < 2; i++ {
-		dirName := "base" + strconv.Itoa(i)
-		if err := fs.Mkdir(dirName, 0o755); err != nil {
-			t.Error(err)
-			return
-		}
-		for j := 0; j < 1; j++ {
-			f, err := fs.Create(filepath.Join(dirName, "file"+strconv.Itoa(j)))
-			if err != nil {
-				t.Error(err)
-				return
-			}
-			_ = f.Close()
-			if err := fs.Mkdir(filepath.Join(dirName, "dir"+strconv.Itoa(j)), 0o755); err != nil {
-				t.Error(err)
-				return
-			}
-			f, err = fs.Create(filepath.Join(dirName, "dir"+strconv.Itoa(j), "file"+strconv.Itoa(j)))
-			if err != nil {
-				t.Error(err)
-				return
-			}
-			_ = f.Close()
-		}
-	}
-
-	t.Run("walk starting at the filesystem root", func(t *testing.T) {
-		pathsTraversed, err := fs.testWalkDirAt("")
-		if err != nil {
-			t.Error(err)
-			return
-		}
-		expect := []Path{
-			{Name: ".", Relative: "."},
-			{Name: "base0", Relative: "base0"},
-			{Name: "dir0", Relative: "base0/dir0"},
-			{Name: "file0", Relative: "base0/dir0/file0"},
-			{Name: "file0", Relative: "base0/file0"},
-			{Name: "base1", Relative: "base1"},
-			{Name: "dir0", Relative: "base1/dir0"},
-			{Name: "file0", Relative: "base1/dir0/file0"},
-			{Name: "file0", Relative: "base1/file0"},
-		}
-		if !reflect.DeepEqual(pathsTraversed, expect) {
-			t.Log(pathsTraversed)
-			t.Log(expect)
-			t.Error("walk doesn't match")
-			return
-		}
-	})
-
-	t.Run("walk starting in a directory", func(t *testing.T) {
-		pathsTraversed, err := fs.testWalkDirAt("base0")
-		if err != nil {
-			t.Error(err)
-			return
-		}
-		expect := []Path{
-			// TODO: what should relative actually be here?
-			// The behaviour differs from walking the directory root vs a sub
-			// directory. When walking from the root, dirfd is the directory we
-			// are walking from and both name and relative are `.`. However,
-			// when walking from a subdirectory, fd is the parent of the
-			// subdirectory, and name is the subdirectory.
-			{Name: "base0", Relative: "."},
-			{Name: "dir0", Relative: "dir0"},
-			{Name: "file0", Relative: "dir0/file0"},
-			{Name: "file0", Relative: "file0"},
-		}
-		if !reflect.DeepEqual(pathsTraversed, expect) {
-			t.Log(pathsTraversed)
-			t.Log(expect)
-			t.Error("walk doesn't match")
-			return
-		}
-	})
-}
-
-type Path struct {
-	Name     string
-	Relative string
-}
-
-func (fs *testUnixFS) testWalkDirAt(path string) ([]Path, error) {
-	dirfd, name, closeFd, err := fs.SafePath(path)
-	defer closeFd()
-	if err != nil {
-		return nil, err
-	}
-	var pathsTraversed []Path
-	if err := fs.WalkDirat(dirfd, name, func(_ int, name, relative string, _ ufs.DirEntry, err error) error {
-		if err != nil {
-			return err
-		}
-		pathsTraversed = append(pathsTraversed, Path{Name: name, Relative: relative})
-		return nil
-	}); err != nil {
-		return nil, err
-	}
-	slices.SortStableFunc(pathsTraversed, func(a, b Path) int {
-		if a.Relative > b.Relative {
-			return 1
-		}
-		if a.Relative < b.Relative {
-			return -1
-		}
-		return 0
-	})
-	return pathsTraversed, nil
-}

internal/ufs/go.LICENSE

@@ -1,27 +0,0 @@
-Copyright (c) 2009 The Go Authors. All rights reserved.
-
-Redistribution and use in source and binary forms, with or without
-modification, are permitted provided that the following conditions are
-met:
-
-   * Redistributions of source code must retain the above copyright
-notice, this list of conditions and the following disclaimer.
-   * Redistributions in binary form must reproduce the above
-copyright notice, this list of conditions and the following disclaimer
-in the documentation and/or other materials provided with the
-distribution.
-   * Neither the name of Google Inc. nor the names of its
-contributors may be used to endorse or promote products derived from
-this software without specific prior written permission.
-
-THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

internal/ufs/mkdir_unix.go

@@ -1,63 +0,0 @@
-// SPDX-License-Identifier: BSD-3-Clause
-
-// Code in this file was derived from `go/src/os/path.go`.
-
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the `go.LICENSE` file.
-
-//go:build unix
-
-package ufs
-
-// mkdirAll is a recursive Mkdir implementation that properly handles symlinks.
-func (fs *UnixFS) mkdirAll(name string, mode FileMode) error {
-	// Fast path: if we can tell whether path is a directory or file, stop with success or error.
-	dir, err := fs.Lstat(name)
-	if err == nil {
-		if dir.Mode()&ModeSymlink != 0 {
-			// If the final path is a symlink, resolve its target and use that
-			// to check instead.
-			dir, err = fs.Stat(name)
-			if err != nil {
-				return err
-			}
-		}
-		if dir.IsDir() {
-			return nil
-		}
-		return &PathError{Op: "mkdir", Path: name, Err: ErrNotDirectory}
-	}
-
-	// Slow path: make sure parent exists and then call Mkdir for path.
-	i := len(name)
-	for i > 0 && name[i-1] == '/' { // Skip trailing path separator.
-		i--
-	}
-
-	j := i
-	for j > 0 && name[j-1] != '/' { // Scan backward over element.
-		j--
-	}
-
-	if j > 1 {
-		// Create parent.
-		err = fs.mkdirAll(name[:j-1], mode)
-		if err != nil {
-			return err
-		}
-	}
-
-	// Parent now exists; invoke Mkdir and use its result.
-	err = fs.Mkdir(name, mode)
-	if err != nil {
-		// Handle arguments like "foo/." by
-		// double-checking that directory doesn't exist.
-		dir, err1 := fs.Lstat(name)
-		if err1 == nil && dir.IsDir() {
-			return nil
-		}
-		return err
-	}
-	return nil
-}

internal/ufs/path_unix.go

@@ -1,80 +0,0 @@
-// SPDX-License-Identifier: BSD-3-Clause
-
-// Code in this file was copied from `go/src/os/path.go`
-// and `go/src/os/path_unix.go`.
-
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the `go.LICENSE` file.
-
-//go:build unix
-
-package ufs
-
-import (
-	"os"
-)
-
-// basename removes trailing slashes and the leading directory name from path name.
-func basename(name string) string {
-	i := len(name) - 1
-	// Remove trailing slashes
-	for ; i > 0 && name[i] == '/'; i-- {
-		name = name[:i]
-	}
-	// Remove leading directory name
-	for i--; i >= 0; i-- {
-		if name[i] == '/' {
-			name = name[i+1:]
-			break
-		}
-	}
-	return name
-}
-
-// endsWithDot reports whether the final component of path is ".".
-func endsWithDot(path string) bool {
-	if path == "." {
-		return true
-	}
-	if len(path) >= 2 && path[len(path)-1] == '.' && os.IsPathSeparator(path[len(path)-2]) {
-		return true
-	}
-	return false
-}
-
-// splitPath returns the base name and parent directory.
-func splitPath(path string) (string, string) {
-	// if no better parent is found, the path is relative from "here"
-	dirname := "."
-
-	// Remove all but one leading slash.
-	for len(path) > 1 && path[0] == '/' && path[1] == '/' {
-		path = path[1:]
-	}
-
-	i := len(path) - 1
-
-	// Remove trailing slashes.
-	for ; i > 0 && path[i] == '/'; i-- {
-		path = path[:i]
-	}
-
-	// if no slashes in path, base is path
-	basename := path
-
-	// Remove leading directory path
-	for i--; i >= 0; i-- {
-		if path[i] == '/' {
-			if i == 0 {
-				dirname = path[:1]
-			} else {
-				dirname = path[:i]
-			}
-			basename = path[i+1:]
-			break
-		}
-	}
-
-	return dirname, basename
-}

internal/ufs/removeall_unix.go

@@ -1,261 +0,0 @@
-// SPDX-License-Identifier: BSD-3-Clause
-
-// Code in this file was derived from `go/src/os/removeall_at.go`.
-
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the `go.LICENSE` file.
-
-//go:build unix
-
-package ufs
-
-import (
-	"errors"
-	"io"
-	"os"
-
-	"golang.org/x/sys/unix"
-)
-
-type unixFS interface {
-	Open(name string) (File, error)
-	Remove(name string) error
-	unlinkat(dirfd int, path string, flags int) error
-}
-
-func (fs *UnixFS) removeAll(path string) error {
-	return removeAll(fs, path)
-}
-
-func removeAll(fs unixFS, path string) error {
-	if path == "" {
-		// fail silently to retain compatibility with previous behavior
-		// of RemoveAll. See issue https://go.dev/issue/28830.
-		return nil
-	}
-
-	// The rmdir system call does not permit removing ".",
-	// so we don't permit it either.
-	if endsWithDot(path) {
-		return &PathError{Op: "removeall", Path: path, Err: unix.EINVAL}
-	}
-
-	// Simple case: if Remove works, we're done.
-	err := fs.Remove(path)
-	if err == nil || errors.Is(err, ErrNotExist) {
-		return nil
-	}
-
-	// RemoveAll recurses by deleting the path base from
-	// its parent directory
-	parentDir, base := splitPath(path)
-
-	parent, err := fs.Open(parentDir)
-	if err != nil {
-		if !errors.Is(err, ErrNotExist) {
-			return err
-		}
-		// If parent does not exist, base cannot exist. Fail silently
-		return nil
-	}
-	defer parent.Close()
-
-	if err := removeAllFrom(fs, parent, base); err != nil {
-		if pathErr, ok := err.(*PathError); ok {
-			pathErr.Path = parentDir + string(os.PathSeparator) + pathErr.Path
-			err = convertErrorType(pathErr)
-		} else {
-			err = ensurePathError(err, "removeallfrom", base)
-		}
-		return err
-	}
-	return nil
-}
-
-func (fs *UnixFS) removeContents(path string) error {
-	return removeContents(fs, path)
-}
-
-func removeContents(fs unixFS, path string) error {
-	if path == "" {
-		// fail silently to retain compatibility with previous behavior
-		// of RemoveAll. See issue https://go.dev/issue/28830.
-		return nil
-	}
-
-	// RemoveAll recurses by deleting the path base from
-	// its parent directory
-	parentDir, base := splitPath(path)
-
-	parent, err := fs.Open(parentDir)
-	if err != nil {
-		if !errors.Is(err, ErrNotExist) {
-			return err
-		}
-		// If parent does not exist, base cannot exist. Fail silently
-		return nil
-	}
-	defer parent.Close()
-
-	if err := removeContentsFrom(fs, parent, base); err != nil {
-		if pathErr, ok := err.(*PathError); ok {
-			pathErr.Path = parentDir + string(os.PathSeparator) + pathErr.Path
-			err = convertErrorType(pathErr)
-		} else {
-			err = ensurePathError(err, "removecontentsfrom", base)
-		}
-		return err
-	}
-	return nil
-}
-
-// removeContentsFrom recursively removes all descendants of parent without
-// removing parent itself. Parent must be a directory.
-func removeContentsFrom(fs unixFS, parent File, base string) error {
-	parentFd := int(parent.Fd())
-
-	var recurseErr error
-	for {
-		const reqSize = 1024
-		var respSize int
-
-		// Open the directory to recurse into
-		file, err := openFdAt(parentFd, base)
-		if err != nil {
-			if errors.Is(err, ErrNotExist) {
-				return nil
-			}
-			recurseErr = &PathError{Op: "openfdat", Path: base, Err: err}
-			break
-		}
-
-		for {
-			numErr := 0
-
-			names, readErr := file.Readdirnames(reqSize)
-			// Errors other than EOF should stop us from continuing.
-			if readErr != nil && readErr != io.EOF {
-				_ = file.Close()
-				if errors.Is(readErr, ErrNotExist) {
-					return nil
-				}
-				return &PathError{Op: "readdirnames", Path: base, Err: readErr}
-			}
-
-			respSize = len(names)
-			for _, name := range names {
-				err := removeAllFrom(fs, file, name)
-				if err != nil {
-					if pathErr, ok := err.(*PathError); ok {
-						pathErr.Path = base + string(os.PathSeparator) + pathErr.Path
-					}
-					numErr++
-					if recurseErr == nil {
-						recurseErr = err
-					}
-				}
-			}
-
-			// If we can delete any entry, break to start new iteration.
-			// Otherwise, we discard current names, get next entries and try deleting them.
-			if numErr != reqSize {
-				break
-			}
-		}
-
-		// Removing files from the directory may have caused
-		// the OS to reshuffle it. Simply calling Readdirnames
-		// again may skip some entries. The only reliable way
-		// to avoid this is to close and re-open the
-		// directory. See issue https://go.dev/issue/20841.
-		_ = file.Close()
-
-		// Finish when the end of the directory is reached
-		if respSize < reqSize {
-			break
-		}
-	}
-
-	return nil
-}
-
-func removeAllFrom(fs unixFS, parent File, base string) error {
-	parentFd := int(parent.Fd())
-
-	// Simple case: if Unlink (aka remove) works, we're done.
-	err := fs.unlinkat(parentFd, base, 0)
-	if err == nil || errors.Is(err, ErrNotExist) {
-		return nil
-	}
-
-	// EISDIR means that we have a directory, and we need to
-	// remove its contents.
-	// EPERM or EACCES means that we don't have write permission on
-	// the parent directory, but this entry might still be a directory
-	// whose contents need to be removed.
-	// Otherwise, just return the error.
-	if err != unix.EISDIR && err != unix.EPERM && err != unix.EACCES {
-		return &PathError{Op: "unlinkat", Path: base, Err: err}
-	}
-
-	// Is this a directory we need to recurse into?
-	var statInfo unix.Stat_t
-	statErr := ignoringEINTR(func() error {
-		return unix.Fstatat(parentFd, base, &statInfo, AT_SYMLINK_NOFOLLOW)
-	})
-	if statErr != nil {
-		if errors.Is(statErr, ErrNotExist) {
-			return nil
-		}
-		return &PathError{Op: "fstatat", Path: base, Err: statErr}
-	}
-	if statInfo.Mode&unix.S_IFMT != unix.S_IFDIR {
-		// Not a directory; return the error from the unix.Unlinkat.
-		return &PathError{Op: "unlinkat", Path: base, Err: err}
-	}
-
-	// Remove all contents will remove the contents of the directory.
-	//
-	// It was split out of this function to allow the deletion of the
-	// contents of a directory, without deleting the directory itself.
-	recurseErr := removeContentsFrom(fs, parent, base)
-
-	// Remove the directory itself.
-	unlinkErr := fs.unlinkat(parentFd, base, AT_REMOVEDIR)
-	if unlinkErr == nil || errors.Is(unlinkErr, ErrNotExist) {
-		return nil
-	}
-
-	if recurseErr != nil {
-		return recurseErr
-	}
-
-	return ensurePathError(err, "unlinkat", base)
-}
-
-// openFdAt opens path relative to the directory in fd.
-// Other than that this should act like openFileNolog.
-// This acts like openFileNolog rather than OpenFile because
-// we are going to (try to) remove the file.
-// The contents of this file are not relevant for test caching.
-func openFdAt(dirfd int, name string) (File, error) {
-	var fd int
-	for {
-		var err error
-		fd, err = unix.Openat(dirfd, name, O_RDONLY|O_CLOEXEC|O_NOFOLLOW, 0)
-		if err == nil {
-			break
-		}
-
-		// See comment in openFileNolog.
-		if err == unix.EINTR {
-			continue
-		}
-
-		return nil, err
-	}
-	// This is stupid, os.NewFile immediately casts `fd` to an `int`, but wants
-	// it to be passed as a `uintptr`.
-	return os.NewFile(uintptr(fd), name), nil
-}

internal/ufs/stat_unix.go

@@ -1,67 +0,0 @@
-// SPDX-License-Identifier: BSD-3-Clause
-
-// Code in this file was copied from `go/src/os/stat_linux.go`
-// and `go/src/os/types_unix.go`.
-
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the `go.LICENSE` file.
-
-//go:build unix
-
-package ufs
-
-import (
-	"time"
-
-	"golang.org/x/sys/unix"
-)
-
-type fileStat struct {
-	name    string
-	size    int64
-	mode    FileMode
-	modTime time.Time
-	sys     unix.Stat_t
-}
-
-var _ FileInfo = (*fileStat)(nil)
-
-func (fs *fileStat) Size() int64        { return fs.size }
-func (fs *fileStat) Mode() FileMode     { return fs.mode }
-func (fs *fileStat) ModTime() time.Time { return fs.modTime }
-func (fs *fileStat) Sys() any           { return &fs.sys }
-func (fs *fileStat) Name() string       { return fs.name }
-func (fs *fileStat) IsDir() bool        { return fs.Mode().IsDir() }
-
-func fillFileStatFromSys(fs *fileStat, name string) {
-	fs.name = basename(name)
-	fs.size = fs.sys.Size
-	fs.modTime = time.Unix(fs.sys.Mtim.Unix())
-	fs.mode = FileMode(fs.sys.Mode & 0o777)
-	switch fs.sys.Mode & unix.S_IFMT {
-	case unix.S_IFBLK:
-		fs.mode |= ModeDevice
-	case unix.S_IFCHR:
-		fs.mode |= ModeDevice | ModeCharDevice
-	case unix.S_IFDIR:
-		fs.mode |= ModeDir
-	case unix.S_IFIFO:
-		fs.mode |= ModeNamedPipe
-	case unix.S_IFLNK:
-		fs.mode |= ModeSymlink
-	case unix.S_IFREG:
-		// nothing to do
-	case unix.S_IFSOCK:
-		fs.mode |= ModeSocket
-	}
-	if fs.sys.Mode&unix.S_ISGID != 0 {
-		fs.mode |= ModeSetgid
-	}
-	if fs.sys.Mode&unix.S_ISUID != 0 {
-		fs.mode |= ModeSetuid
-	}
-	if fs.sys.Mode&unix.S_ISVTX != 0 {
-		fs.mode |= ModeSticky
-	}
-}

internal/ufs/walk.go

@@ -1,124 +0,0 @@
-// SPDX-License-Identifier: BSD-3-Clause
-
-// Code in this file was derived from `go/src/io/fs/walk.go`.
-
-// Copyright 2020 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the `go.LICENSE` file.
-
-package ufs
-
-import (
-	iofs "io/fs"
-	"path"
-)
-
-// SkipDir is used as a return value from [WalkDirFunc] to indicate that
-// the directory named in the call is to be skipped. It is not returned
-// as an error by any function.
-var SkipDir = iofs.SkipDir
-
-// SkipAll is used as a return value from [WalkDirFunc] to indicate that
-// all remaining files and directories are to be skipped. It is not returned
-// as an error by any function.
-var SkipAll = iofs.SkipAll
-
-// WalkDirFunc is the type of the function called by [WalkDir] to visit
-// each file or directory.
-//
-// The path argument contains the argument to [WalkDir] as a prefix.
-// That is, if WalkDir is called with root argument "dir" and finds a file
-// named "a" in that directory, the walk function will be called with
-// argument "dir/a".
-//
-// The d argument is the [DirEntry] for the named path.
-//
-// The error result returned by the function controls how [WalkDir]
-// continues. If the function returns the special value [SkipDir], WalkDir
-// skips the current directory (path if d.IsDir() is true, otherwise
-// path's parent directory). If the function returns the special value
-// [SkipAll], WalkDir skips all remaining files and directories. Otherwise,
-// if the function returns a non-nil error, WalkDir stops entirely and
-// returns that error.
-//
-// The err argument reports an error related to path, signaling that
-// [WalkDir] will not walk into that directory. The function can decide how
-// to handle that error; as described earlier, returning the error will
-// cause WalkDir to stop walking the entire tree.
-//
-// [WalkDir] calls the function with a non-nil err argument in two cases.
-//
-// First, if the initial [Stat] on the root directory fails, WalkDir
-// calls the function with path set to root, d set to nil, and err set to
-// the error from [fs.Stat].
-//
-// Second, if a directory's ReadDir method (see [ReadDirFile]) fails, WalkDir calls the
-// function with path set to the directory's path, d set to an
-// [DirEntry] describing the directory, and err set to the error from
-// ReadDir. In this second case, the function is called twice with the
-// path of the directory: the first call is before the directory read is
-// attempted and has err set to nil, giving the function a chance to
-// return [SkipDir] or [SkipAll] and avoid the ReadDir entirely. The second call
-// is after a failed ReadDir and reports the error from ReadDir.
-// (If ReadDir succeeds, there is no second call.)
-type WalkDirFunc func(path string, d DirEntry, err error) error
-
-// WalkDir walks the file tree rooted at root, calling fn for each file or
-// directory in the tree, including root.
-//
-// All errors that arise visiting files and directories are filtered by fn:
-// see the [WalkDirFunc] documentation for details.
-//
-// The files are walked in lexical order, which makes the output deterministic
-// but requires WalkDir to read an entire directory into memory before proceeding
-// to walk that directory.
-//
-// WalkDir does not follow symbolic links found in directories,
-// but if root itself is a symbolic link, its target will be walked.
-func WalkDir(fs Filesystem, root string, fn WalkDirFunc) error {
-	info, err := fs.Stat(root)
-	if err != nil {
-		err = fn(root, nil, err)
-	} else {
-		err = walkDir(fs, root, iofs.FileInfoToDirEntry(info), fn)
-	}
-	if err == SkipDir || err == SkipAll {
-		return nil
-	}
-	return err
-}
-
-// walkDir recursively descends path, calling walkDirFn.
-func walkDir(fs Filesystem, name string, d DirEntry, walkDirFn WalkDirFunc) error {
-	if err := walkDirFn(name, d, nil); err != nil || !d.IsDir() {
-		if err == SkipDir && d.IsDir() {
-			// Successfully skipped directory.
-			err = nil
-		}
-		return err
-	}
-
-	dirs, err := fs.ReadDir(name)
-	if err != nil {
-		// Second call, to report ReadDir error.
-		err = walkDirFn(name, d, err)
-		if err != nil {
-			if err == SkipDir && d.IsDir() {
-				err = nil
-			}
-			return err
-		}
-	}
-
-	for _, d1 := range dirs {
-		name1 := path.Join(name, d1.Name())
-		if err := walkDir(fs, name1, d1, walkDirFn); err != nil {
-			if err == SkipDir {
-				break
-			}
-			return err
-		}
-	}
-
-	return nil
-}

internal/ufs/walk_unix.go

@@ -1,314 +0,0 @@
-// SPDX-License-Identifier: BSD-2-Clause
-
-// Some code in this file was derived from https://github.com/karrick/godirwalk.
-
-//go:build unix
-
-package ufs
-
-import (
-	"bytes"
-	"fmt"
-	iofs "io/fs"
-	"os"
-	"path"
-	"reflect"
-	"unsafe"
-
-	"golang.org/x/sys/unix"
-)
-
-type WalkDiratFunc func(dirfd int, name, relative string, d DirEntry, err error) error
-
-func (fs *UnixFS) WalkDirat(dirfd int, name string, fn WalkDiratFunc) error {
-	info, err := fs.Lstatat(dirfd, name)
-	if err != nil {
-		err = fn(dirfd, name, ".", nil, err)
-	} else {
-		b := newScratchBuffer()
-		err = fs.walkDir(b, dirfd, name, ".", iofs.FileInfoToDirEntry(info), fn)
-	}
-	if err == SkipDir || err == SkipAll {
-		return nil
-	}
-	return err
-}
-
-func (fs *UnixFS) walkDir(b []byte, parentfd int, name, relative string, d DirEntry, walkDirFn WalkDiratFunc) error {
-	if err := walkDirFn(parentfd, name, relative, d, nil); err != nil || !d.IsDir() {
-		if err == SkipDir && d.IsDir() {
-			// Successfully skipped directory.
-			err = nil
-		}
-		return err
-	}
-
-	dirfd, err := fs.openat(parentfd, name, O_DIRECTORY|O_RDONLY, 0)
-	if dirfd != 0 {
-		defer unix.Close(dirfd)
-	}
-	if err != nil {
-		return err
-	}
-
-	dirs, err := fs.readDir(dirfd, name, relative, b)
-	if err != nil {
-		// Second call, to report ReadDir error.
-		err = walkDirFn(dirfd, name, relative, d, err)
-		if err != nil {
-			if err == SkipDir && d.IsDir() {
-				err = nil
-			}
-			return err
-		}
-	}
-
-	for _, d1 := range dirs {
-		name := d1.Name()
-		// This fancy logic ensures that if we start walking from a subdirectory
-		// that we don't make the path relative to the root of the filesystem.
-		//
-		// For example, if we walk from the root of a filesystem, relative would
-		// be "." and path.Join would end up just returning name. But if relative
-		// was a subdirectory, relative could be "dir" and path.Join would make
-		// it "dir/child" even though we are walking starting at dir.
-		var rel string
-		if relative == "." {
-			rel = name
-		} else {
-			rel = path.Join(relative, name)
-		}
-		if err := fs.walkDir(b, dirfd, name, rel, d1, walkDirFn); err != nil {
-			if err == SkipDir {
-				break
-			}
-			return err
-		}
-	}
-
-	return nil
-}
-
-// ReadDirMap .
-// TODO: document
-func ReadDirMap[T any](fs *UnixFS, path string, fn func(DirEntry) (T, error)) ([]T, error) {
-	dirfd, name, closeFd, err := fs.safePath(path)
-	defer closeFd()
-	if err != nil {
-		return nil, err
-	}
-	fd, err := fs.openat(dirfd, name, O_DIRECTORY|O_RDONLY, 0)
-	if err != nil {
-		return nil, err
-	}
-	defer unix.Close(fd)
-
-	entries, err := fs.readDir(fd, ".", path, nil)
-	if err != nil {
-		return nil, err
-	}
-
-	out := make([]T, len(entries))
-	for i, e := range entries {
-		idx := i
-		e := e
-		v, err := fn(e)
-		if err != nil {
-			return nil, err
-		}
-		out[idx] = v
-	}
-
-	return out, nil
-}
-
-// nameOffset is a compile time constant
-const nameOffset = int(unsafe.Offsetof(unix.Dirent{}.Name))
-
-func nameFromDirent(de *unix.Dirent) (name []byte) {
-	// Because this GOOS' syscall.Dirent does not provide a field that specifies
-	// the name length, this function must first calculate the max possible name
-	// length, and then search for the NULL byte.
-	ml := int(de.Reclen) - nameOffset
-
-	// Convert syscall.Dirent.Name, which is array of int8, to []byte, by
-	// overwriting Cap, Len, and Data slice header fields to the max possible
-	// name length computed above, and finding the terminating NULL byte.
-	//
-	// TODO: is there an alternative to the deprecated SliceHeader?
-	// SliceHeader was mainly deprecated due to it being misused for avoiding
-	// allocations when converting a byte slice to a string, ref;
-	// https://go.dev/issue/53003
-	sh := (*reflect.SliceHeader)(unsafe.Pointer(&name))
-	sh.Cap = ml
-	sh.Len = ml
-	sh.Data = uintptr(unsafe.Pointer(&de.Name[0]))
-
-	if index := bytes.IndexByte(name, 0); index >= 0 {
-		// Found NULL byte; set slice's cap and len accordingly.
-		sh.Cap = index
-		sh.Len = index
-		return
-	}
-
-	// NOTE: This branch is not expected, but included for defensive
-	// programming, and provides a hard stop on the name based on the structure
-	// field array size.
-	sh.Cap = len(de.Name)
-	sh.Len = sh.Cap
-	return
-}
-
-// modeTypeFromDirent converts a syscall defined constant, which is in purview
-// of OS, to a constant defined by Go, assumed by this project to be stable.
-//
-// When the syscall constant is not recognized, this function falls back to a
-// Stat on the file system.
-func (fs *UnixFS) modeTypeFromDirent(de *unix.Dirent, fd int, name string) (FileMode, error) {
-	switch de.Type {
-	case unix.DT_REG:
-		return 0, nil
-	case unix.DT_DIR:
-		return ModeDir, nil
-	case unix.DT_LNK:
-		return ModeSymlink, nil
-	case unix.DT_CHR:
-		return ModeDevice | ModeCharDevice, nil
-	case unix.DT_BLK:
-		return ModeDevice, nil
-	case unix.DT_FIFO:
-		return ModeNamedPipe, nil
-	case unix.DT_SOCK:
-		return ModeSocket, nil
-	default:
-		// If syscall returned unknown type (e.g., DT_UNKNOWN, DT_WHT), then
-		// resolve actual mode by reading file information.
-		return fs.modeType(fd, name)
-	}
-}
-
-// modeType returns the mode type of the file system entry identified by
-// osPathname by calling os.LStat function, to intentionally not follow symbolic
-// links.
-//
-// Even though os.LStat provides all file mode bits, we want to ensure same
-// values returned to caller regardless of whether we obtained file mode bits
-// from syscall or stat call. Therefore, mask out the additional file mode bits
-// that are provided by stat but not by the syscall, so users can rely on their
-// values.
-func (fs *UnixFS) modeType(dirfd int, name string) (FileMode, error) {
-	fi, err := fs.Lstatat(dirfd, name)
-	if err != nil {
-		return 0, fmt.Errorf("ufs: error finding mode type for %s during readDir: %w", name, err)
-	}
-	return fi.Mode() & ModeType, nil
-}
-
-var minimumScratchBufferSize = os.Getpagesize()
-
-func newScratchBuffer() []byte {
-	return make([]byte, minimumScratchBufferSize)
-}
-
-func (fs *UnixFS) readDir(fd int, name, relative string, b []byte) ([]DirEntry, error) {
-	scratchBuffer := b
-	if scratchBuffer == nil || len(scratchBuffer) < minimumScratchBufferSize {
-		scratchBuffer = newScratchBuffer()
-	}
-
-	var entries []DirEntry
-	var workBuffer []byte
-
-	var sde unix.Dirent
-	for {
-		if len(workBuffer) == 0 {
-			n, err := unix.Getdents(fd, scratchBuffer)
-			if err != nil {
-				if err == unix.EINTR {
-					continue
-				}
-				return nil, ensurePathError(err, "getdents", name)
-			}
-			if n <= 0 {
-				// end of directory: normal exit
-				return entries, nil
-			}
-			workBuffer = scratchBuffer[:n] // trim work buffer to number of bytes read
-		}
-
-		// "Go is like C, except that you just put `unsafe` all over the place".
-		copy((*[unsafe.Sizeof(unix.Dirent{})]byte)(unsafe.Pointer(&sde))[:], workBuffer)
-		workBuffer = workBuffer[sde.Reclen:] // advance buffer for next iteration through loop
-
-		if sde.Ino == 0 {
-			continue // inode set to 0 indicates an entry that was marked as deleted
-		}
-
-		nameSlice := nameFromDirent(&sde)
-		nameLength := len(nameSlice)
-
-		if nameLength == 0 || (nameSlice[0] == '.' && (nameLength == 1 || (nameLength == 2 && nameSlice[1] == '.'))) {
-			continue
-		}
-
-		childName := string(nameSlice)
-		mt, err := fs.modeTypeFromDirent(&sde, fd, childName)
-		if err != nil {
-			return nil, err
-		}
-		var rel string
-		if relative == "." {
-			rel = name
-		} else {
-			rel = path.Join(relative, childName)
-		}
-		entries = append(entries, &dirent{dirfd: fd, name: childName, path: rel, modeType: mt, fs: fs})
-	}
-}
-
-// dirent stores the name and file system mode type of discovered file system
-// entries.
-type dirent struct {
-	dirfd    int
-	name     string
-	path     string
-	modeType FileMode
-
-	fs *UnixFS
-}
-
-func (de dirent) Name() string {
-	return de.name
-}
-
-func (de dirent) IsDir() bool {
-	return de.modeType&ModeDir != 0
-}
-
-func (de dirent) Type() FileMode {
-	return de.modeType
-}
-
-func (de dirent) Info() (FileInfo, error) {
-	if de.fs == nil {
-		return nil, nil
-	}
-	return de.fs.Lstatat(de.dirfd, de.name)
-	// return de.fs.Lstat(de.path)
-}
-
-func (de dirent) Open() (File, error) {
-	if de.fs == nil {
-		return nil, nil
-	}
-	return de.fs.OpenFileat(de.dirfd, de.name, O_RDONLY, 0)
-	// return de.fs.OpenFile(de.path, O_RDONLY, 0)
-}
-
-// reset releases memory held by entry err and name, and resets mode type to 0.
-func (de *dirent) reset() {
-	de.name = ""
-	de.path = ""
-	de.modeType = 0
-	de.dirfd = 0
-}

parser/parser.go

@@ -5,6 +5,7 @@ import (
 	"bytes"
 	"encoding/json"
 	"io"
+	"os"
 	"strconv"
 	"strings"
 
@@ -18,7 +19,6 @@ import (
 	"gopkg.in/yaml.v3"
 
 	"github.com/pterodactyl/wings/config"
-	"github.com/pterodactyl/wings/internal/ufs"
 )
 
 // The file parsing options that are available for a server configuration file.
@@ -161,14 +161,14 @@ func (cfr *ConfigurationFileReplacement) UnmarshalJSON(data []byte) error {
 	iv, err := jsonparser.GetString(data, "if_value")
 	// We only check keypath here since match & replace_with should be present on all of
 	// them, however if_value is optional.
-	if err != nil && err != jsonparser.KeyPathNotFoundError {
+	if err != nil && !errors.Is(err, jsonparser.KeyPathNotFoundError) {
 		return err
 	}
 	cfr.IfValue = iv
 
 	rw, dt, _, err := jsonparser.Get(data, "replace_with")
 	if err != nil {
-		if err != jsonparser.KeyPathNotFoundError {
+		if !errors.Is(err, jsonparser.KeyPathNotFoundError) {
 			return err
 		}
 
@@ -190,7 +190,7 @@ func (cfr *ConfigurationFileReplacement) UnmarshalJSON(data []byte) error {
 
 // Parse parses a given configuration file and updates all the values within
 // as defined in the API response from the Panel.
-func (f *ConfigurationFile) Parse(file ufs.File) error {
+func (f *ConfigurationFile) Parse(file *os.File) error {
 	// log.WithField("path", path).WithField("parser", f.Parser.String()).Debug("parsing server configuration file")
 
 	// What the fuck is going on here?
@@ -220,7 +220,7 @@ func (f *ConfigurationFile) Parse(file ufs.File) error {
 }
 
 // Parses an xml file.
-func (f *ConfigurationFile) parseXmlFile(file ufs.File) error {
+func (f *ConfigurationFile) parseXmlFile(file *os.File) error {
 	doc := etree.NewDocument()
 	if _, err := doc.ReadFrom(file); err != nil {
 		return err
@@ -299,7 +299,7 @@ func (f *ConfigurationFile) parseXmlFile(file ufs.File) error {
 }
 
 // Parses an ini file.
-func (f *ConfigurationFile) parseIniFile(file ufs.File) error {
+func (f *ConfigurationFile) parseIniFile(file *os.File) error {
 	// Wrap the file in a NopCloser so the ini package doesn't close the file.
 	cfg, err := ini.Load(io.NopCloser(file))
 	if err != nil {
@@ -380,7 +380,7 @@ func (f *ConfigurationFile) parseIniFile(file ufs.File) error {
 // Parses a json file updating any matching key/value pairs. If a match is not found, the
 // value is set regardless in the file. See the commentary in parseYamlFile for more details
 // about what is happening during this process.
-func (f *ConfigurationFile) parseJsonFile(file ufs.File) error {
+func (f *ConfigurationFile) parseJsonFile(file *os.File) error {
 	b, err := io.ReadAll(file)
 	if err != nil {
 		return err
@@ -407,7 +407,7 @@ func (f *ConfigurationFile) parseJsonFile(file ufs.File) error {
 
 // Parses a yaml file and updates any matching key/value pairs before persisting
 // it back to the disk.
-func (f *ConfigurationFile) parseYamlFile(file ufs.File) error {
+func (f *ConfigurationFile) parseYamlFile(file *os.File) error {
 	b, err := io.ReadAll(file)
 	if err != nil {
 		return err
@@ -456,7 +456,7 @@ func (f *ConfigurationFile) parseYamlFile(file ufs.File) error {
 // Parses a text file using basic find and replace. This is a highly inefficient method of
 // scanning a file and performing a replacement. You should attempt to use anything other
 // than this function where possible.
-func (f *ConfigurationFile) parseTextFile(file ufs.File) error {
+func (f *ConfigurationFile) parseTextFile(file *os.File) error {
 	b := bytes.NewBuffer(nil)
 	s := bufio.NewScanner(file)
 	var replaced bool
@@ -518,7 +518,7 @@ func (f *ConfigurationFile) parseTextFile(file ufs.File) error {
 //
 // @see https://github.com/pterodactyl/panel/issues/2308 (original)
 // @see https://github.com/pterodactyl/panel/issues/3009 ("bug" introduced as result)
-func (f *ConfigurationFile) parsePropertiesFile(file ufs.File) error {
+func (f *ConfigurationFile) parsePropertiesFile(file *os.File) error {
 	b, err := io.ReadAll(file)
 	if err != nil {
 		return err

router/middleware/request_error.go

@@ -118,9 +118,9 @@ func (re *RequestError) asFilesystemError() (int, string) {
 		return 0, ""
 	}
 	if filesystem.IsErrorCode(err, filesystem.ErrNotExist) ||
-		filesystem.IsErrorCode(err, filesystem.ErrCodePathResolution) ||
-		strings.Contains(err.Error(), "resolves to a location outside the server root") {
-		return http.StatusNotFound, "The requested resources was not found on the system."
+		filesystem.IsPathError(err) ||
+		filesystem.IsLinkError(err) {
+		return http.StatusNotFound, "The requested file or folder does not exist on the system."
 	}
 	if filesystem.IsErrorCode(err, filesystem.ErrCodeDenylistFile) || strings.Contains(err.Error(), "filesystem: file access prohibited") {
 		return http.StatusForbidden, "This file cannot be modified: present in egg denylist."

router/router_download.go

@@ -56,8 +56,8 @@ func getDownloadBackup(c *gin.Context) {
 		return
 	}
 
-	// The use of `os` here is safe as backups are not stored within server
-	// accessible directories.
+	// The use of `os` here is safe as backups are not stored within server access
+	// directories, and this path is program-controlled, not user input.
 	f, err := os.Open(b.Path())
 	if err != nil {
 		middleware.CaptureAndAbort(c, err)

router/router_server.go

@@ -225,21 +225,26 @@ func deleteServer(c *gin.Context) {
 	// done in a separate process since failure is not the end of the world and can be
 	// manually cleaned up after the fact.
 	//
-	// In addition, servers with large amounts of files can take some time to finish deleting,
+	// In addition, servers with large numbers of files can take some time to finish deleting,
 	// so we don't want to block the HTTP call while waiting on this.
-	go func(s *server.Server) {
-		fs := s.Filesystem()
-		p := fs.Path()
-		_ = fs.UnixFS().Close()
+	p := s.Filesystem().Path()
+	go func(p string) {
 		if err := os.RemoveAll(p); err != nil {
 			log.WithFields(log.Fields{"path": p, "error": err}).Warn("failed to remove server files during deletion process")
 		}
-	}(s)
+	}(p)
+
+	if err := s.Filesystem().Close(); err != nil {
+		log.WithFields(log.Fields{"server": s.ID(), "error": err}).Warn("failed to close filesystem root")
+	}
 
 	middleware.ExtractManager(c).Remove(func(server *server.Server) bool {
 		return server.ID() == s.ID()
 	})
 
+	// Deallocate the reference to this server.
+	s = nil
+
 	c.Status(http.StatusNoContent)
 }
 

router/router_server_files.go

@@ -30,8 +30,7 @@ import (
 // getServerFileContents returns the contents of a file on the server.
 func getServerFileContents(c *gin.Context) {
 	s := middleware.ExtractServer(c)
-	p := strings.TrimLeft(c.Query("file"), "/")
-	f, st, err := s.Filesystem().File(p)
+	f, st, err := s.Filesystem().File(c.Query("file"))
 	if err != nil {
 		middleware.CaptureAndAbort(c, err)
 		return
@@ -129,6 +128,7 @@ func putServerRenameFiles(c *gin.Context) {
 				}
 				if err := fs.Rename(pf, pt); err != nil {
 					// Return nil if the error is an is not exists.
+					// NOTE: os.IsNotExist() does not work if the error is wrapped.
 					if errors.Is(err, os.ErrNotExist) {
 						s.Log().WithField("error", err).
 							WithField("from_path", pf).
@@ -421,9 +421,15 @@ func postServerCompressFiles(c *gin.Context) {
 		return
 	}
 
-	f, err := s.Filesystem().CompressFiles(data.RootPath, data.Files)
+	f, err := s.Filesystem().CompressFiles(c.Request.Context(), data.RootPath, data.Files)
 	if err != nil {
-		middleware.CaptureAndAbort(c, err)
+		if errors.Is(err, filesystem.ErrNoSpaceAvailable) {
+			c.AbortWithStatusJSON(http.StatusConflict, gin.H{
+				"error": "This server does not have enough available disk space to generate a compressed archive.",
+			})
+		} else {
+			middleware.CaptureAndAbort(c, err)
+		}
 		return
 	}
 
@@ -447,17 +453,6 @@ func postServerDecompressFiles(c *gin.Context) {
 
 	s := middleware.ExtractServer(c)
 	lg := middleware.ExtractLogger(c).WithFields(log.Fields{"root_path": data.RootPath, "file": data.File})
-	lg.Debug("checking if space is available for file decompression")
-	err := s.Filesystem().SpaceAvailableForDecompression(context.Background(), data.RootPath, data.File)
-	if err != nil {
-		if filesystem.IsErrorCode(err, filesystem.ErrCodeUnknownArchive) {
-			lg.WithField("error", err).Warn("failed to decompress file: unknown archive format")
-			c.AbortWithStatusJSON(http.StatusBadRequest, gin.H{"error": "The archive provided is in a format Wings does not understand."})
-			return
-		}
-		middleware.CaptureAndAbort(c, err)
-		return
-	}
 
 	lg.Info("starting file decompression")
 	if err := s.Filesystem().DecompressFile(context.Background(), data.RootPath, data.File); err != nil {
@@ -621,7 +616,6 @@ func handleFileUpload(p string, s *server.Server, header *multipart.FileHeader)
 	if err := s.Filesystem().IsIgnored(p); err != nil {
 		return err
 	}
-
 	if err := s.Filesystem().Write(p, file, header.Size, 0o644); err != nil {
 		return err
 	}

router/router_transfer.go

@@ -106,9 +106,11 @@ func postTransfers(c *gin.Context) {
 			if !successful && err != nil {
 				// Delete all extracted files.
 				go func(trnsfr *transfer.Transfer) {
-					_ = trnsfr.Server.Filesystem().UnixFS().Close()
-					if err := os.RemoveAll(trnsfr.Server.Filesystem().Path()); err != nil && !os.IsNotExist(err) {
-						trnsfr.Log().WithError(err).Warn("failed to delete local server files")
+					_ = trnsfr.Server.Filesystem().Close()
+					if err := os.RemoveAll(trnsfr.Server.Filesystem().Path()); err != nil {
+						if !errors.Is(err, os.ErrNotExist) {
+							trnsfr.Log().WithError(err).Warn("failed to delete local server files")
+						}
 					}
 				}(trnsfr)
 			}
@@ -166,7 +168,7 @@ out:
 			case "archive":
 				trnsfr.Log().Debug("received archive")
 
-				if err := trnsfr.Server.EnsureDataDirectoryExists(); err != nil {
+				if _, err := trnsfr.Server.EnsureDataDirectoryExists(); err != nil {
 					middleware.CaptureAndAbort(c, err)
 					return
 				}

server/backup.go

@@ -67,7 +67,7 @@ func (s *Server) Backup(b backup.BackupInterface) error {
 		}
 	}
 
-	ad, err := b.Generate(s.Context(), s.Filesystem(), ignored)
+	ad, err := b.Generate(s.Context(), s.Filesystem().Path(), ignored)
 	if err != nil {
 		if err := s.notifyPanelOfBackup(b.Identifier(), &backup.ArchiveDetails{}, false); err != nil {
 			s.Log().WithFields(log.Fields{
@@ -153,13 +153,27 @@ func (s *Server) RestoreBackup(b backup.BackupInterface, reader io.ReadCloser) (
 	s.Log().Debug("starting file writing process for backup restoration")
 	err = b.Restore(s.Context(), reader, func(file string, info fs.FileInfo, r io.ReadCloser) error {
 		defer r.Close()
-		s.Events().Publish(DaemonMessageEvent, "(restoring): "+file)
-		// TODO: since this will be called a lot, it may be worth adding an optimized
-		// Write with Chtimes method to the UnixFS that is able to re-use the
-		// same dirfd and file name.
-		if err := s.Filesystem().Write(file, r, info.Size(), info.Mode()); err != nil {
-			return err
+		if file == "." {
+			return nil
 		}
+
+		s.Events().Publish(DaemonMessageEvent, "(restoring): "+file)
+		if info.IsDir() {
+			if err := s.Filesystem().Mkdir(file, info.Mode().Perm()); err != nil {
+				if !errors.Is(err, os.ErrExist) {
+					return errors.WithStack(err)
+				}
+			}
+		} else {
+			if !info.Mode().IsRegular() {
+				return nil
+			}
+
+			if err := s.Filesystem().Write(file, r, info.Size(), info.Mode().Perm()); err != nil {
+				return errors.WithStack(err)
+			}
+		}
+
 		atime := info.ModTime()
 		return s.Filesystem().Chtimes(file, atime, atime)
 	})

server/backup/backup.go

@@ -16,7 +16,6 @@ import (
 
 	"github.com/pterodactyl/wings/config"
 	"github.com/pterodactyl/wings/remote"
-	"github.com/pterodactyl/wings/server/filesystem"
 )
 
 var format = archives.CompressedArchive{
@@ -48,7 +47,7 @@ type BackupInterface interface {
 	WithLogContext(map[string]interface{})
 	// Generate creates a backup in whatever the configured source for the
 	// specific implementation is.
-	Generate(context.Context, *filesystem.Filesystem, string) (*ArchiveDetails, error)
+	Generate(context.Context, string, string) (*ArchiveDetails, error)
 	// Ignored returns the ignored files for this backup instance.
 	Ignored() string
 	// Checksum returns a SHA1 checksum for the generated backup.

server/backup/backup_local.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"io"
 	"os"
+	"strings"
 
 	"emperror.dev/errors"
 	"github.com/juju/ratelimit"
@@ -59,14 +60,24 @@ func (b *LocalBackup) WithLogContext(c map[string]interface{}) {
 
 // Generate generates a backup of the selected files and pushes it to the
 // defined location for this instance.
-func (b *LocalBackup) Generate(ctx context.Context, fsys *filesystem.Filesystem, ignore string) (*ArchiveDetails, error) {
-	a := &filesystem.Archive{
-		Filesystem: fsys,
-		Ignore:     ignore,
+func (b *LocalBackup) Generate(ctx context.Context, basePath, ignore string) (*ArchiveDetails, error) {
+	r, err := os.OpenRoot(basePath)
+	if err != nil {
+		return nil, errors.Wrap(err, "server/backup: failed to open root directory")
+	}
+	defer r.Close()
+	a, err := filesystem.NewArchive(r, "/", filesystem.WithIgnored(strings.Split(ignore, "\n")))
+	if err != nil {
+		return nil, errors.WrapIf(err, "server/backup: failed to create archive")
 	}
 
 	b.log().WithField("path", b.Path()).Info("creating backup for server")
-	if err := a.Create(ctx, b.Path()); err != nil {
+	f, err := os.OpenFile(b.Path(), os.O_WRONLY|os.O_CREATE|os.O_TRUNC, 0o644)
+	if err != nil {
+		return nil, errors.Wrap(err, "server/backup: failed to open file for writing")
+	}
+	defer f.Close()
+	if err := a.Create(ctx, f); err != nil {
 		return nil, err
 	}
 	b.log().Info("created backup successfully")

server/backup/backup_s3.go

@@ -7,6 +7,7 @@ import (
 	"net/http"
 	"os"
 	"strconv"
+	"strings"
 	"time"
 
 	"emperror.dev/errors"
@@ -48,27 +49,36 @@ func (s *S3Backup) WithLogContext(c map[string]interface{}) {
 
 // Generate creates a new backup on the disk, moves it into the S3 bucket via
 // the provided presigned URL, and then deletes the backup from the disk.
-func (s *S3Backup) Generate(ctx context.Context, fsys *filesystem.Filesystem, ignore string) (*ArchiveDetails, error) {
+func (s *S3Backup) Generate(ctx context.Context, basePath, ignore string) (*ArchiveDetails, error) {
 	defer s.Remove()
 
-	a := &filesystem.Archive{
-		Filesystem: fsys,
-		Ignore:     ignore,
+	r, err := os.OpenRoot(basePath)
+	if err != nil {
+		return nil, errors.Wrap(err, "backup: failed to open root directory")
+	}
+	defer r.Close()
+	a, err := filesystem.NewArchive(r, "/", filesystem.WithIgnored(strings.Split(ignore, "\n")))
+	if err != nil {
+		return nil, errors.WrapIf(err, "backup: failed to create archive")
 	}
 
 	s.log().WithField("path", s.Path()).Info("creating backup for server")
-	if err := a.Create(ctx, s.Path()); err != nil {
+	f, err := os.OpenFile(s.Path(), os.O_WRONLY|os.O_CREATE|os.O_TRUNC, 0o644)
+	if err != nil {
+		return nil, errors.Wrap(err, "backup: failed to open file for writing")
+	}
+	defer f.Close()
+	if err := a.Create(ctx, f); err != nil {
 		return nil, err
 	}
 	s.log().Info("created backup successfully")
 
-	rc, err := os.Open(s.Path())
-	if err != nil {
-		return nil, errors.Wrap(err, "backup: could not read archive from disk")
+	_ = f.Sync()
+	if _, err := f.Seek(0, io.SeekStart); err != nil {
+		return nil, errors.Wrap(err, "backup: failed to seek on file")
 	}
-	defer rc.Close()
 
-	parts, err := s.generateRemoteRequest(ctx, rc)
+	parts, err := s.generateRemoteRequest(ctx, f)
 	if err != nil {
 		return nil, err
 	}

server/config_parser.go

@@ -1,34 +1,31 @@
 package server
 
 import (
+	"os"
 	"runtime"
 
 	"github.com/gammazero/workerpool"
-
-	"github.com/pterodactyl/wings/internal/ufs"
 )
 
-// UpdateConfigurationFiles updates all the defined configuration files for
+// UpdateConfigurationFiles updates all of the defined configuration files for
 // a server automatically to ensure that they always use the specified values.
 func (s *Server) UpdateConfigurationFiles() {
 	pool := workerpool.New(runtime.NumCPU())
-
-	s.Log().Debug("acquiring process configuration files...")
 	files := s.ProcessConfiguration().ConfigurationFiles
-	s.Log().Debug("acquired process configuration files")
+
 	for _, cf := range files {
 		f := cf
 
 		pool.Submit(func() {
-			file, err := s.Filesystem().UnixFS().Touch(f.FileName, ufs.O_RDWR|ufs.O_CREATE, 0o644)
+			fd, err := s.Filesystem().Touch(f.FileName, os.O_RDWR|os.O_CREATE, 0o644)
 			if err != nil {
-				s.Log().WithField("file_name", f.FileName).WithField("error", err).Error("failed to open file for configuration")
+				s.Log().WithField("file_name", f.FileName).WithField("error", err).Error("failed to open configuration file")
 				return
 			}
-			defer file.Close()
+			defer fd.Close()
 
-			if err := f.Parse(file); err != nil {
-				s.Log().WithField("error", err).Error("failed to parse and update server configuration file")
+			if err := f.Parse(fd); err != nil {
+				s.Log().WithField("error", err).WithField("file_name", f.FileName).Error("failed to parse and update server configuration file")
 			}
 
 			s.Log().WithField("file_name", f.FileName).Debug("finished processing server configuration file")

server/filesystem/archive.go

@@ -11,18 +11,18 @@ import (
 	"sync"
 
 	"emperror.dev/errors"
-	"github.com/apex/log"
 	"github.com/juju/ratelimit"
 	"github.com/klauspost/pgzip"
 	ignore "github.com/sabhiram/go-gitignore"
 
 	"github.com/pterodactyl/wings/config"
 	"github.com/pterodactyl/wings/internal/progress"
-	"github.com/pterodactyl/wings/internal/ufs"
 )
 
 const memory = 4 * 1024
 
+var ErrNoSpaceAvailable = errors.Sentinel("archive: no space available on disk")
+
 var pool = sync.Pool{
 	New: func() interface{} {
 		b := make([]byte, memory)
@@ -36,7 +36,8 @@ type TarProgress struct {
 	p *progress.Progress
 }
 
-// NewTarProgress .
+// NewTarProgress returns a new progress writer for the tar file. This is a wrapper
+// around the standard writer with a progress instance embedded.
 func NewTarProgress(w *tar.Writer, p *progress.Progress) *TarProgress {
 	if p != nil {
 		p.Writer = w
@@ -55,44 +56,79 @@ func (p *TarProgress) Write(v []byte) (int, error) {
 	return p.p.Write(v)
 }
 
+type ArchiveOption func(a *Archive) error
+
 type Archive struct {
-	// Filesystem to create the archive with.
-	Filesystem *Filesystem
-
-	// Ignore is a gitignore string (most likely read from a file) of files to ignore
-	// from the archive.
-	Ignore string
-
-	// BaseDirectory .
-	BaseDirectory string
-
-	// Files specifies the files to archive, this takes priority over the Ignore
-	// option, if unspecified, all files in the BaseDirectory will be archived
-	// unless Ignore is set.
-	Files []string
-
-	// Progress wraps the writer of the archive to pass through the progress tracker.
-	Progress *progress.Progress
-
-	w *TarProgress
+	root     *os.Root
+	dir      string
+	pw       *TarProgress
+	ignored  *ignore.GitIgnore
+	matching *ignore.GitIgnore
+	p        *progress.Progress
 }
 
-// Create creates an archive at dst with all the files defined in the
-// included Files array.
-//
-// THIS IS UNSAFE TO USE IF `dst` IS PROVIDED BY A USER! ONLY USE THIS WITH
-// CONTROLLED PATHS!
-func (a *Archive) Create(ctx context.Context, dst string) error {
-	// Using os.OpenFile here is expected, as long as `dst` is not a user
-	// provided path.
-	f, err := os.OpenFile(dst, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, 0o600)
-	if err != nil {
-		return err
+// NewArchive returns a new archive instance that can be used for generating an
+// archive of files and folders within the provided os.Root. The "dir" value is
+// a child directory within the `os.Root` instance.
+func NewArchive(r *os.Root, dir string, opts ...ArchiveOption) (*Archive, error) {
+	a := &Archive{root: r, dir: dir}
+	for _, opt := range opts {
+		if err := opt(a); err != nil {
+			return nil, errors.Wrap(err, "server/filesystem: archive: failed to apply callback option")
+		}
 	}
-	defer f.Close()
+	return a, nil
+}
 
+func WithProgress(p *progress.Progress) ArchiveOption {
+	return func(a *Archive) error {
+		a.p = p
+		return nil
+	}
+}
+
+func WithIgnored(files []string) ArchiveOption {
+	return func(a *Archive) error {
+		if a.matching != nil {
+			return errors.NewPlain("cannot create an archive with both ignored and matching configurations")
+		}
+
+		a.ignored = ignore.CompileIgnoreLines(files...)
+
+		return nil
+	}
+}
+
+func WithMatching(files []string) ArchiveOption {
+	return func(a *Archive) error {
+		if a.ignored != nil {
+			return errors.NewPlain("cannot create an archive with both ignored and matching configurations")
+		}
+
+		lines := make([]string, len(files))
+		for _, f := range files {
+			// The old archiver logic just accepted an array of paths to include in the
+			// archive and did rudimentary logic to determine if they should be included.
+			// This newer logic makes use of the gitignore (flipped to make it an allowlist),
+			// but to do that we need to make sure all the provided values here start with a
+			// slash; otherwise files/folders nested deeply might be unintentionally included.
+			lines = append(lines, "/"+strings.TrimPrefix(f, "/"))
+		}
+
+		a.matching = ignore.CompileIgnoreLines(lines...)
+
+		return nil
+	}
+}
+
+func (a *Archive) Progress() *progress.Progress {
+	return a.p
+}
+
+// Create .
+func (a *Archive) Create(ctx context.Context, f *os.File) error {
 	// Select a writer based off of the WriteLimit configuration option. If there is no
-	// write limit, use the file as the writer.
+	// write limit use the file as the writer.
 	var writer io.Writer
 	if writeLimit := int64(config.Get().System.Backups.WriteLimit * 1024 * 1024); writeLimit > 0 {
 		// Token bucket with a capacity of "writeLimit" MiB, adding "writeLimit" MiB/s
@@ -105,30 +141,9 @@ func (a *Archive) Create(ctx context.Context, dst string) error {
 	return a.Stream(ctx, writer)
 }
 
-type walkFunc func(dirfd int, name, relative string, d ufs.DirEntry) error
-
-// Stream streams the creation of the archive to the given writer.
+// Stream walks the given root directory and generates an archive from the
+// provided files.
 func (a *Archive) Stream(ctx context.Context, w io.Writer) error {
-	if a.Filesystem == nil {
-		return errors.New("filesystem: archive.Filesystem is unset")
-	}
-
-	// The base directory may come with a prefixed `/`, strip it to prevent
-	// problems.
-	a.BaseDirectory = strings.TrimPrefix(a.BaseDirectory, "/")
-
-	if filesLen := len(a.Files); filesLen > 0 {
-		files := make([]string, filesLen)
-		for i, f := range a.Files {
-			if !strings.HasPrefix(f, a.Filesystem.Path()) {
-				files[i] = f
-				continue
-			}
-			files[i] = strings.TrimPrefix(strings.TrimPrefix(f, a.Filesystem.Path()), "/")
-		}
-		a.Files = files
-	}
-
 	// Choose which compression level to use based on the compression_level configuration option
 	var compressionLevel int
 	switch config.Get().System.Backups.CompressionLevel {
@@ -149,124 +164,55 @@ func (a *Archive) Stream(ctx context.Context, w io.Writer) error {
 	tw := tar.NewWriter(gw)
 	defer tw.Close()
 
-	a.w = NewTarProgress(tw, a.Progress)
+	a.pw = NewTarProgress(tw, a.p)
+	defer a.pw.Close()
 
-	fs := a.Filesystem.unixFS
-
-	// If we're specifically looking for only certain files, or have requested
-	// that certain files be ignored we'll update the callback function to reflect
-	// that request.
-	var callback walkFunc
-	if len(a.Files) == 0 && len(a.Ignore) > 0 {
-		i := ignore.CompileIgnoreLines(strings.Split(a.Ignore, "\n")...)
-		callback = a.callback(func(_ int, _, relative string, _ ufs.DirEntry) error {
-			if i.MatchesPath(relative) {
-				return SkipThis
-			}
-			return nil
-		})
-	} else if len(a.Files) > 0 {
-		callback = a.withFilesCallback()
-	} else {
-		callback = a.callback()
-	}
-
-	// Open the base directory we were provided.
-	dirfd, name, closeFd, err := fs.SafePath(a.BaseDirectory)
-	defer closeFd()
+	r, err := a.root.OpenRoot(normalize(a.dir))
 	if err != nil {
-		return err
+		return errors.Wrap(err, "server/filesystem: archive: failed to acquire root dir instance")
 	}
+	defer r.Close()
 
-	// Recursively walk the base directory.
-	return fs.WalkDirat(dirfd, name, func(dirfd int, name, relative string, d ufs.DirEntry, err error) error {
-		if err != nil {
-			return err
-		}
-		select {
-		case <-ctx.Done():
-			return ctx.Err()
-		default:
-			return callback(dirfd, name, relative, d)
-		}
-	})
+	base := strings.TrimRight(r.Name(), "./")
+	return filepath.WalkDir(base, a.walker(ctx, base))
 }
 
 // Callback function used to determine if a given file should be included in the archive
 // being generated.
-func (a *Archive) callback(opts ...walkFunc) walkFunc {
-	// Get the base directory we need to strip when walking.
-	//
-	// This is important as when we are walking, the last part of the base directory
-	// is present on all the paths we walk.
-	var base string
-	if a.BaseDirectory != "" {
-		base = filepath.Base(a.BaseDirectory) + "/"
-	}
-	return func(dirfd int, name, relative string, d ufs.DirEntry) error {
-		// Skip directories because we are walking them recursively.
-		if d.IsDir() {
+func (a *Archive) walker(ctx context.Context, base string) fs.WalkDirFunc {
+	return func(path string, de fs.DirEntry, err error) error {
+		if ctx.Err() != nil {
+			return ctx.Err()
+		}
+
+		if err != nil {
+			return fs.SkipDir
+		}
+
+		path = strings.TrimPrefix(path, base)
+		if a.ignored != nil && a.ignored.MatchesPath(path) {
 			return nil
 		}
 
-		// If base isn't empty, strip it from the relative path. This fixes an
-		// issue when creating an archive starting from a nested directory.
-		//
-		// See https://github.com/pterodactyl/panel/issues/5030 for more details.
-		if base != "" {
-			relative = strings.TrimPrefix(relative, base)
-		}
-
-		// Call the additional options passed to this callback function. If any of them return
-		// a non-nil error we will exit immediately.
-		for _, opt := range opts {
-			if err := opt(dirfd, name, relative, d); err != nil {
-				if err == SkipThis {
-					return nil
-				}
-				return err
-			}
+		if a.matching != nil && !a.matching.MatchesPath(path) {
+			return nil
 		}
 
 		// Add the file to the archive, if it is nested in a directory,
 		// the directory will be automatically "created" in the archive.
-		return a.addToArchive(dirfd, name, relative, d)
+		return a.addToArchive(path)
 	}
 }
 
-var SkipThis = errors.New("skip this")
-
-// Pushes only files defined in the Files key to the final archive.
-func (a *Archive) withFilesCallback() walkFunc {
-	return a.callback(func(_ int, _, relative string, _ ufs.DirEntry) error {
-		for _, f := range a.Files {
-			// Allow exact file matches, otherwise check if file is within a parent directory.
-			//
-			// The slashes are added in the prefix checks to prevent partial name matches from being
-			// included in the archive.
-			if f != relative && !strings.HasPrefix(strings.TrimSuffix(relative, "/")+"/", strings.TrimSuffix(f, "/")+"/") {
-				continue
-			}
-
-			// Once we have a match return a nil value here so that the loop stops and the
-			// call to this function will correctly include the file in the archive. If there
-			// are no matches we'll never make it to this line, and the final error returned
-			// will be the ufs.SkipDir error.
-			return nil
-		}
-
-		return SkipThis
-	})
-}
-
 // Adds a given file path to the final archive being created.
-func (a *Archive) addToArchive(dirfd int, name, relative string, entry ufs.DirEntry) error {
-	s, err := entry.Info()
+func (a *Archive) addToArchive(p string) error {
+	p = normalize(p)
+	s, err := a.root.Lstat(p)
 	if err != nil {
-		if errors.Is(err, ufs.ErrNotExist) {
+		if os.IsNotExist(err) {
 			return nil
 		}
-		return errors.WrapIff(err, "failed executing os.Lstat on '%s'", name)
+		return errors.Wrap(err, "server/filesystem: archive: failed to stat file")
 	}
 
 	// Skip socket files as they are unsupported by archive/tar.
@@ -278,34 +224,27 @@ func (a *Archive) addToArchive(dirfd int, name, relative string, entry ufs.DirEn
 	// Resolve the symlink target if the file is a symlink.
 	var target string
 	if s.Mode()&fs.ModeSymlink != 0 {
-		// Read the target of the symlink. If there are any errors we will dump them out to
-		// the logs, but we're not going to stop the backup. There are far too many cases of
-		// symlinks causing all sorts of unnecessary pain in this process. Sucks to suck if
-		// it doesn't work.
-		target, err = os.Readlink(s.Name())
+		// This intentionally uses [os.Readlink] and not the [os.Root] instance. We need to
+		// know the actual target for the symlink, even if outside the server directory, so
+		// that we can restore it properly.
+		//
+		// This target is only used for the sake of keeping everything correct in the archive;
+		// we never read the target file contents.
+		target, err = os.Readlink(filepath.Join(a.root.Name(), p))
 		if err != nil {
-			// Ignore the not exist errors specifically, since there is nothing important about that.
-			if !os.IsNotExist(err) {
-				log.WithField("name", name).WithField("readlink_err", err.Error()).Warn("failed reading symlink for target path; skipping...")
-			}
-			return nil
+			target = ""
 		}
 	}
 
-	// Get the tar FileInfoHeader in order to add the file to the archive.
-	header, err := tar.FileInfoHeader(s, filepath.ToSlash(target))
+	// Get the tar FileInfoHeader to add the file to the archive.
+	header, err := tar.FileInfoHeader(s, target)
 	if err != nil {
-		return errors.WrapIff(err, "failed to get tar#FileInfoHeader for '%s'", name)
+		return errors.Wrap(err, "server/filesystem: archive: failed to get file info header")
 	}
 
-	// Fix the header name if the file is not a symlink.
-	if s.Mode()&fs.ModeSymlink == 0 {
-		header.Name = relative
-	}
-
-	// Write the tar FileInfoHeader to the archive.
-	if err := a.w.WriteHeader(header); err != nil {
-		return errors.WrapIff(err, "failed to write tar#FileInfoHeader for '%s'", name)
+	header.Name = p
+	if err := a.pw.WriteHeader(header); err != nil {
+		return errors.Wrap(err, "server/filesystem: archive: failed to write tar header")
 	}
 
 	// If the size of the file is less than 1 (most likely for symlinks), skip writing the file.
@@ -326,19 +265,18 @@ func (a *Archive) addToArchive(dirfd int, name, relative string, entry ufs.DirEn
 		}()
 	}
 
-	// Open the file.
-	f, err := a.Filesystem.unixFS.OpenFileat(dirfd, name, ufs.O_RDONLY, 0)
+	f, err := a.root.Open(p)
 	if err != nil {
 		if os.IsNotExist(err) {
 			return nil
 		}
-		return errors.WrapIff(err, "failed to open '%s' for copying", header.Name)
+		return errors.Wrap(err, "server/filesystem: archive: failed to open file for copying")
 	}
 	defer f.Close()
 
-	// Copy the file's contents to the archive using our buffer.
-	if _, err := io.CopyBuffer(a.w, io.LimitReader(f, header.Size), buf); err != nil {
-		return errors.WrapIff(err, "failed to copy '%s' to archive", header.Name)
+	if _, err := io.CopyBuffer(a.pw, io.LimitReader(f, header.Size), buf); err != nil {
+		return errors.Wrap(err, "server/filesystem: archive: failed to copy file to archive")
 	}
+
 	return nil
 }

server/filesystem/archive_test.go

@@ -15,49 +15,39 @@ import (
 
 func TestArchive_Stream(t *testing.T) {
 	g := Goblin(t)
-	fs, rfs := NewFs()
+	fs := NewFs()
 
 	g.Describe("Archive", func() {
 		g.AfterEach(func() {
-			// Reset the filesystem after each run.
-			_ = fs.TruncateRootDirectory()
+			fs.reset()
 		})
 
 		g.It("creates archive with intended files", func() {
 			g.Assert(fs.CreateDirectory("test", "/")).IsNil()
 			g.Assert(fs.CreateDirectory("test2", "/")).IsNil()
 
-			r := strings.NewReader("hello, world!\n")
-			err := fs.Write("test/file.txt", r, r.Size(), 0o644)
+			err := fs.Writefile("test/file.txt", strings.NewReader("hello, world!\n"))
 			g.Assert(err).IsNil()
 
-			r = strings.NewReader("hello, world!\n")
-			err = fs.Write("test2/file.txt", r, r.Size(), 0o644)
+			err = fs.Writefile("test2/file.txt", strings.NewReader("hello, world!\n"))
 			g.Assert(err).IsNil()
 
-			r = strings.NewReader("hello, world!\n")
-			err = fs.Write("test_file.txt", r, r.Size(), 0o644)
+			err = fs.Writefile("test_file.txt", strings.NewReader("hello, world!\n"))
 			g.Assert(err).IsNil()
 
-			r = strings.NewReader("hello, world!\n")
-			err = fs.Write("test_file.txt.old", r, r.Size(), 0o644)
+			err = fs.Writefile("test_file.txt.old", strings.NewReader("hello, world!\n"))
 			g.Assert(err).IsNil()
 
-			a := &Archive{
-				Filesystem: fs,
-				Files: []string{
-					"test",
-					"test_file.txt",
-				},
+			archivePath := filepath.Join(fs.rootPath, "../archive.tar.gz")
+			f, err := os.Create(archivePath)
+			if err != nil {
+				panic(err)
 			}
+			defer f.Close()
 
-			// Create the archive.
-			archivePath := filepath.Join(rfs.root, "archive.tar.gz")
-			g.Assert(a.Create(context.Background(), archivePath)).IsNil()
+			a, err := NewArchive(fs.root, ".", WithMatching([]string{"test", "test_file.txt"}))
 
-			// Ensure the archive exists.
-			_, err = os.Stat(archivePath)
-			g.Assert(err).IsNil()
+			g.Assert(a.Create(context.Background(), f)).IsNil()
 
 			// Open the archive.
 			genericFs, err := archives.FileSystem(context.Background(), archivePath, nil)
@@ -84,6 +74,55 @@ func TestArchive_Stream(t *testing.T) {
 
 			g.Assert(files).Equal(expected)
 		})
+
+		g.It("does not archive files outside of root", func() {
+			if err := os.MkdirAll(filepath.Join(fs.rootPath, "../outer"), 0o755); err != nil {
+				panic(err)
+			}
+
+			fs.write("test.txt", []byte("test"))
+			fs.write("../danger-1.txt", []byte("danger"))
+			fs.write("../outer/danger-2.txt", []byte("danger"))
+
+			if err := os.Symlink("../danger-1.txt", filepath.Join(fs.rootPath, "symlink.txt")); err != nil {
+				panic(err)
+			}
+
+			if err := os.Symlink("../outer", filepath.Join(fs.rootPath, "danger-dir")); err != nil {
+				panic(err)
+			}
+
+			archivePath := filepath.Join(fs.rootPath, "../archive.tar.gz")
+			f, err := os.Create(archivePath)
+			if err != nil {
+				panic(err)
+			}
+			defer f.Close()
+
+			a, err := NewArchive(fs.root, ".")
+			if err != nil {
+				panic(err)
+			}
+
+			err = a.Create(context.Background(), f)
+			g.Assert(err).IsNil()
+
+			// Open the archive.
+			genericFs, err := archives.FileSystem(context.Background(), archivePath, nil)
+			g.Assert(err).IsNil()
+
+			// Assert that we are opening an archive.
+			afs, ok := genericFs.(iofs.ReadDirFS)
+			g.Assert(ok).IsTrue()
+
+			// Get the names of the files recursively from the archive.
+			files, err := getFiles(afs, ".")
+			g.Assert(err).IsNil()
+			// We expect the actual symlinks themselves, but not the contents of the directory
+			// or the file itself. We're storing the symlinked file in the archive so that
+			// expanding it back is the same, but you won't have the inner contents.
+			g.Assert(files).Equal([]string{"danger-dir", "symlink.txt", "test.txt"})
+		})
 	})
 }
 

server/filesystem/archiverext/compressed.go

@@ -1,100 +0,0 @@
-// SPDX-License-Identifier: MIT
-// SPDX-FileCopyrightText: Copyright (c) 2016 Matthew Holt
-
-// Code in this file was derived from
-// https://github.com/mholt/archiver/blob/v4.0.0-alpha.8/fs.go
-//
-// These modifications were necessary to allow us to use an already open file
-// with archiver.FileFS.
-
-package archiverext
-
-import (
-	"io"
-	"io/fs"
-
-	"github.com/mholt/archives"
-)
-
-// FileFS allows accessing a file on disk using a consistent file system interface.
-// The value should be the path to a regular file, not a directory. This file will
-// be the only entry in the file system and will be at its root. It can be accessed
-// within the file system by the name of "." or the filename.
-//
-// If the file is compressed, set the Compression field so that reads from the
-// file will be transparently decompressed.
-type FileFS struct {
-	// File is the compressed file backing the FileFS.
-	File fs.File
-
-	// If file is compressed, setting this field will
-	// transparently decompress reads.
-	Compression archives.Decompressor
-}
-
-// Open opens the named file, which must be the file used to create the file system.
-func (f FileFS) Open(name string) (fs.File, error) {
-	if err := f.checkName(name, "open"); err != nil {
-		return nil, err
-	}
-	if f.Compression == nil {
-		return f.File, nil
-	}
-	r, err := f.Compression.OpenReader(f.File)
-	if err != nil {
-		return nil, err
-	}
-	return compressedFile{f.File, r}, nil
-}
-
-// ReadDir returns a directory listing with the file as the singular entry.
-func (f FileFS) ReadDir(name string) ([]fs.DirEntry, error) {
-	if err := f.checkName(name, "stat"); err != nil {
-		return nil, err
-	}
-	info, err := f.Stat(name)
-	if err != nil {
-		return nil, err
-	}
-	return []fs.DirEntry{fs.FileInfoToDirEntry(info)}, nil
-}
-
-// Stat stats the named file, which must be the file used to create the file system.
-func (f FileFS) Stat(name string) (fs.FileInfo, error) {
-	if err := f.checkName(name, "stat"); err != nil {
-		return nil, err
-	}
-	return f.File.Stat()
-}
-
-func (f FileFS) checkName(name, op string) error {
-	if !fs.ValidPath(name) {
-		return &fs.PathError{Op: "open", Path: name, Err: fs.ErrInvalid}
-	}
-	// TODO: we may need better name validation.
-	if name != "." {
-		return &fs.PathError{Op: op, Path: name, Err: fs.ErrNotExist}
-	}
-	return nil
-}
-
-// compressedFile is an fs.File that specially reads
-// from a decompression reader, and which closes both
-// that reader and the underlying file.
-type compressedFile struct {
-	fs.File
-	decomp io.ReadCloser
-}
-
-func (cf compressedFile) Read(p []byte) (int, error) {
-	return cf.decomp.Read(p)
-}
-
-func (cf compressedFile) Close() error {
-	err := cf.File.Close()
-	err2 := cf.decomp.Close()
-	if err2 != nil && err == nil {
-		err = err2
-	}
-	return err
-}

server/filesystem/chmod.go

@@ -0,0 +1,82 @@
+package filesystem
+
+import (
+	"fmt"
+	fs2 "io/fs"
+	"os"
+	"path/filepath"
+	"strings"
+	"time"
+
+	"emperror.dev/errors"
+	"github.com/pterodactyl/wings/config"
+)
+
+func (fs *Filesystem) Chmod(path string, mode os.FileMode) error {
+	path = strings.TrimLeft(filepath.Clean(path), "/")
+	if path == "" {
+		path = "."
+	}
+	if err := fs.root.Chmod(path, mode); err != nil {
+		return errors.Wrap(err, "server/filesystem: chmod: failed to chmod path")
+	}
+
+	return nil
+}
+
+// Chown recursively iterates over a file or directory and sets the permissions on all the
+// underlying files. Iterate over all the files and directories. If it is a file go ahead
+// and perform the chown operation. Otherwise dig deeper into the directory until we've run
+// out of directories to dig into.
+func (fs *Filesystem) Chown(p string) error {
+	p = normalize(p)
+	uid := config.Get().System.User.Uid
+	gid := config.Get().System.User.Gid
+	if err := fs.root.Chown(p, uid, gid); err != nil {
+		return errors.WrapIf(err, "server/filesystem: chown: failed to chown path")
+	}
+
+	// If this is not a directory, we can now return from the function; there is nothing
+	// left that we need to do.
+	if st, err := fs.root.Stat(p); err != nil || !st.IsDir() {
+		if err == nil || errors.Is(err, os.ErrNotExist) {
+			return nil
+		}
+
+		return errors.WrapIf(err, "server/filesystem: chown: failed to stat path")
+	}
+
+	rt := fs.rootPath
+	if p == "." {
+		r, err := fs.root.OpenRoot(p)
+		if err != nil {
+			return errors.WithStack(err)
+		}
+		defer r.Close()
+		rt = r.Name()
+	}
+
+	// If this was a directory, begin walking over its contents recursively and ensure that all
+	// the subfiles and directories get their permissions updated as well.
+	return filepath.WalkDir(rt, func(path string, _ fs2.DirEntry, err error) error {
+		path = normalize(path)
+		if path == "." {
+			return nil
+		}
+
+		if err := fs.root.Chown(path, uid, gid); err != nil {
+			return errors.Wrap(err, fmt.Sprintf("server/filesystem: chown: failed to chown file"))
+		}
+
+		return nil
+	})
+}
+
+func (fs *Filesystem) Chtimes(path string, atime, mtime time.Time) error {
+	path = strings.TrimLeft(filepath.Clean(path), "/")
+	if err := fs.root.Chtimes(path, atime, mtime); err != nil {
+		return errors.Wrap(err, "server/filesystem: chtimes: failed to chtimes path")
+	}
+
+	return nil
+}

server/filesystem/compress.go

@@ -4,162 +4,182 @@ import (
 	"context"
 	"fmt"
 	"io"
-	iofs "io/fs"
-	"path"
+	"os"
 	"path/filepath"
 	"strings"
-	"sync/atomic"
 	"time"
 
 	"emperror.dev/errors"
-	"github.com/klauspost/compress/zip"
 	"github.com/mholt/archives"
-
-	"github.com/pterodactyl/wings/internal/ufs"
-	"github.com/pterodactyl/wings/server/filesystem/archiverext"
+	"github.com/pterodactyl/wings/internal"
 )
 
+type extractOptions struct {
+	dir    string
+	file   string
+	format archives.Format
+	r      io.Reader
+}
+
 // CompressFiles compresses all the files matching the given paths in the
 // specified directory. This function also supports passing nested paths to only
 // compress certain files and folders when working in a larger directory. This
 // effectively creates a local backup, but rather than ignoring specific files
-// and folders, it takes an allow-list of files and folders.
+// and folders, it takes an allowlist of files and folders.
 //
 // All paths are relative to the dir that is passed in as the first argument,
 // and the compressed file will be placed at that location named
 // `archive-{date}.tar.gz`.
-func (fs *Filesystem) CompressFiles(dir string, paths []string) (ufs.FileInfo, error) {
-	a := &Archive{Filesystem: fs, BaseDirectory: dir, Files: paths}
-	d := path.Join(
-		dir,
-		fmt.Sprintf("archive-%s.tar.gz", strings.ReplaceAll(time.Now().Format(time.RFC3339), ":", "")),
-	)
-	f, err := fs.unixFS.OpenFile(d, ufs.O_WRONLY|ufs.O_CREATE, 0o644)
+func (fs *Filesystem) CompressFiles(ctx context.Context, dir string, paths []string) (os.FileInfo, error) {
+	a, err := NewArchive(fs.root, dir, WithMatching(paths))
 	if err != nil {
-		return nil, err
+		return nil, errors.WrapIf(err, "server/filesystem: compress: failed to create archive instance")
+	}
+
+	n := fmt.Sprintf("archive-%s.tar.gz", strings.ReplaceAll(time.Now().Format(time.RFC3339), ":", ""))
+	f, err := fs.root.OpenFile(normalize(filepath.Join(dir, n)), os.O_WRONLY|os.O_CREATE|os.O_TRUNC, 0o644)
+	if err != nil {
+		return nil, errors.Wrap(err, "server/filesystem: compress: failed to open file for writing")
 	}
 	defer f.Close()
-	cw := ufs.NewCountedWriter(f)
-	if err := a.Stream(context.Background(), cw); err != nil {
+
+	cw := internal.NewCountedWriter(f)
+	// todo: eventing on the counted writer so that we can slowly increase the disk
+	//  used value on the server as the file gets written?
+	if err := a.Stream(ctx, cw); err != nil {
+		return nil, errors.Wrap(err, "server/filesystem: compress: failed to write to disk")
+	}
+	if err := fs.HasSpaceFor(cw.BytesWritten()); err != nil {
+		_ = fs.root.Remove(normalize(filepath.Join(dir, n)))
 		return nil, err
 	}
-	if !fs.unixFS.CanFit(cw.BytesWritten()) {
-		_ = fs.unixFS.Remove(d)
-		return nil, newFilesystemError(ErrCodeDiskSpace, nil)
-	}
-	fs.unixFS.Add(cw.BytesWritten())
+	fs.addDisk(cw.BytesWritten())
+
 	return f.Stat()
 }
 
-func (fs *Filesystem) archiverFileSystem(ctx context.Context, p string) (iofs.FS, error) {
-	f, err := fs.unixFS.Open(p)
-	if err != nil {
-		return nil, err
-	}
-	// Do not use defer to close `f`, it will likely be used later.
-
-	format, _, err := archives.Identify(ctx, filepath.Base(p), f)
-	if err != nil && !errors.Is(err, archives.NoMatch) {
-		_ = f.Close()
-		return nil, err
-	}
-
-	// Reset the file reader.
-	if _, err := f.Seek(0, io.SeekStart); err != nil {
-		_ = f.Close()
-		return nil, err
-	}
-
-	info, err := f.Stat()
-	if err != nil {
-		_ = f.Close()
-		return nil, err
-	}
-
-	if format != nil {
-		switch ff := format.(type) {
-		case archives.Zip:
-			// zip.Reader is more performant than ArchiveFS, because zip.Reader caches content information
-			// and zip.Reader can open several content files concurrently because of io.ReaderAt requirement
-			// while ArchiveFS can't.
-			// zip.Reader doesn't suffer from issue #330 and #310 according to local test (but they should be fixed anyway)
-			return zip.NewReader(f, info.Size())
-		case archives.Extraction:
-			return &archives.ArchiveFS{Stream: io.NewSectionReader(f, 0, info.Size()), Format: ff, Context: ctx}, nil
-		case archives.Compression:
-			return archiverext.FileFS{File: f, Compression: ff}, nil
-		}
-	}
-	_ = f.Close()
-	return nil, archives.NoMatch
-}
-
-// SpaceAvailableForDecompression looks through a given archive and determines
-// if decompressing it would put the server over its allocated disk space limit.
-func (fs *Filesystem) SpaceAvailableForDecompression(ctx context.Context, dir string, file string) error {
-	// Don't waste time trying to determine this if we know the server will have the space for
-	// it since there is no limit.
-	if fs.MaxDisk() <= 0 {
-		return nil
-	}
-
-	fsys, err := fs.archiverFileSystem(ctx, filepath.Join(dir, file))
-	if err != nil {
-		if errors.Is(err, archives.NoMatch) {
-			return newFilesystemError(ErrCodeUnknownArchive, err)
-		}
-		return err
-	}
-
-	var size atomic.Int64
-	return iofs.WalkDir(fsys, ".", func(path string, d iofs.DirEntry, err error) error {
-		if err != nil {
-			return err
-		}
-
-		select {
-		case <-ctx.Done():
-			// Stop walking if the context is canceled.
-			return ctx.Err()
-		default:
-			info, err := d.Info()
-			if err != nil {
-				return err
-			}
-			if !fs.unixFS.CanFit(size.Add(info.Size())) {
-				return newFilesystemError(ErrCodeDiskSpace, nil)
-			}
-			return nil
-		}
-	})
-}
-
 // DecompressFile will decompress a file in a given directory by using the
 // archiver tool to infer the file type and go from there. This will walk over
 // all the files within the given archive and ensure that there is not a
 // zip-slip attack being attempted by validating that the final path is within
 // the server data directory.
 func (fs *Filesystem) DecompressFile(ctx context.Context, dir string, file string) error {
-	f, err := fs.unixFS.Open(filepath.Join(dir, file))
+	f, err := fs.root.Open(normalize(filepath.Join(dir, file)))
 	if err != nil {
-		return err
+		return errors.Wrap(err, "server/filesystem: decompress: failed to open file")
 	}
 	defer f.Close()
 
-	// Identify the type of archive we are dealing with.
 	format, input, err := archives.Identify(ctx, filepath.Base(file), f)
 	if err != nil {
 		if errors.Is(err, archives.NoMatch) {
 			return newFilesystemError(ErrCodeUnknownArchive, err)
 		}
-		return err
+		return errors.Wrap(err, "server/filesystem: decompress: failed to identify archive format")
 	}
 
-	return fs.extractStream(ctx, extractStreamOptions{
-		FileName:  file,
-		Directory: dir,
-		Format:    format,
-		Reader:    input,
+	return fs.extractStream(ctx, extractOptions{dir: dir, file: file, format: format, r: input})
+}
+
+func (fs *Filesystem) extractStream(ctx context.Context, opts extractOptions) error {
+	// See if it's a compressed archive, such as TAR or a ZIP
+	ex, ok := opts.format.(archives.Extractor)
+	if !ok {
+		// If not, check if it's a single-file compression, such as
+		// .log.gz, .sql.gz, and so on
+		de, ok := opts.format.(archives.Decompressor)
+		if !ok {
+			return nil
+		}
+
+		p := filepath.Join(opts.dir, strings.TrimSuffix(opts.file, opts.format.Extension()))
+		if err := fs.IsIgnored(p); err != nil {
+			return nil
+		}
+
+		reader, err := de.OpenReader(opts.r)
+		if err != nil {
+			return errors.Wrap(err, "server/filesystem: decompress: failed to open reader")
+		}
+		defer reader.Close()
+
+		// Open the file for creation/writing
+		f, err := fs.root.OpenFile(normalize(p), os.O_WRONLY|os.O_CREATE, 0o644)
+		if err != nil {
+			return errors.Wrap(err, "server/filesystem: decompress: failed to open file")
+		}
+		defer f.Close()
+
+		// Read in 4 KB chunks
+		buf := make([]byte, 4096)
+		for {
+			n, err := reader.Read(buf)
+			if n > 0 {
+				if err := fs.HasSpaceFor(int64(n)); err != nil {
+					return err
+				}
+				if _, err := f.Write(buf[:n]); err != nil {
+					return errors.Wrap(err, "server/filesystem: decompress: failed to write")
+				}
+				fs.addDisk(int64(n))
+			}
+
+			if err != nil {
+				if err == io.EOF {
+					break
+				}
+				return errors.Wrap(err, "server/filesystem: decompress: failed to read")
+			}
+		}
+
+		return nil
+	}
+
+	// Decompress and extract archive
+	return ex.Extract(ctx, opts.r, func(ctx context.Context, f archives.FileInfo) error {
+		if f.IsDir() {
+			return nil
+		}
+		p := filepath.Join(opts.dir, f.NameInArchive)
+		if err := fs.IsIgnored(p); err != nil {
+			return nil
+		}
+		r, err := f.Open()
+		if err != nil {
+			return err
+		}
+		defer r.Close()
+		if f.Mode()&os.ModeSymlink != 0 {
+			// Try to create the symlink if it is in the archive, but don't hold up the process
+			// if the file cannot be created. In that case just skip over it entirely.
+			if f.LinkTarget != "" {
+				p2 := strings.TrimLeft(filepath.Clean(p), string(filepath.Separator))
+				if p2 == "" {
+					p2 = "."
+				}
+				// We don't use [fs.Symlink] here because that normalizes the source directory for
+				// consistency with the codebase. In this case when decompressing we want to just
+				// accept the source without any normalization.
+				if err := fs.root.Symlink(f.LinkTarget, p2); err != nil {
+					if errors.Is(err, os.ErrNotExist) || IsPathError(err) || IsLinkError(err) {
+						return nil
+					}
+					return errors.Wrap(err, "server/filesystem: decompress: failed to create symlink")
+				}
+			}
+			return nil
+		}
+
+		if err := fs.Write(p, r, f.Size(), f.Mode().Perm()); err != nil {
+			return errors.Wrap(err, "server/filesystem: decompress: failed to write file")
+		}
+
+		// Update the file modification time to the one set in the archive.
+		if err := fs.Chtimes(p, f.ModTime(), f.ModTime()); err != nil {
+			return errors.Wrap(err, "server/filesystem: decompress: failed to update file modification time")
+		}
+
+		return nil
 	})
 }
 
@@ -172,112 +192,9 @@ func (fs *Filesystem) ExtractStreamUnsafe(ctx context.Context, dir string, r io.
 		}
 		return err
 	}
-	return fs.extractStream(ctx, extractStreamOptions{
-		Directory: dir,
-		Format:    format,
-		Reader:    input,
-	})
-}
-
-type extractStreamOptions struct {
-	// The directory to extract the archive to.
-	Directory string
-	// File name of the archive.
-	FileName string
-	// Format of the archive.
-	Format archives.Format
-	// Reader for the archive.
-	Reader io.Reader
-}
-
-func (fs *Filesystem) extractStream(ctx context.Context, opts extractStreamOptions) error {
-	// See if it's a compressed archive, such as TAR or a ZIP
-	ex, ok := opts.Format.(archives.Extractor)
-	if !ok {
-		// If not, check if it's a single-file compression, such as
-		// .log.gz, .sql.gz, and so on
-		de, ok := opts.Format.(archives.Decompressor)
-		if !ok {
-			return nil
-		}
-
-		// Strip the compression suffix
-		p := filepath.Join(opts.Directory, strings.TrimSuffix(opts.FileName, opts.Format.Extension()))
-
-		// Make sure it's not ignored
-		if err := fs.IsIgnored(p); err != nil {
-			return nil
-		}
-
-		reader, err := de.OpenReader(opts.Reader)
-		if err != nil {
-			return err
-		}
-		defer reader.Close()
-
-		// Open the file for creation/writing
-		f, err := fs.unixFS.OpenFile(p, ufs.O_WRONLY|ufs.O_CREATE, 0o644)
-		if err != nil {
-			return err
-		}
-		defer f.Close()
-
-		// Read in 4 KB chunks
-		buf := make([]byte, 4096)
-		for {
-			n, err := reader.Read(buf)
-			if n > 0 {
-
-				// Check quota before writing the chunk
-				if quotaErr := fs.HasSpaceFor(int64(n)); quotaErr != nil {
-					return quotaErr
-				}
-
-				// Write the chunk
-				if _, writeErr := f.Write(buf[:n]); writeErr != nil {
-					return writeErr
-				}
-
-				// Add to quota
-				fs.addDisk(int64(n))
-			}
-
-			if err != nil {
-				// EOF are expected
-				if err == io.EOF {
-					break
-				}
-
-				// Return any other
-				return err
-			}
-		}
-
-		return nil
-	}
-
-	// Decompress and extract archive
-	return ex.Extract(ctx, opts.Reader, func(ctx context.Context, f archives.FileInfo) error {
-		if f.IsDir() {
-			return nil
-		}
-		p := filepath.Join(opts.Directory, f.NameInArchive)
-		// If it is ignored, just don't do anything with the file and skip over it.
-		if err := fs.IsIgnored(p); err != nil {
-			return nil
-		}
-		r, err := f.Open()
-		if err != nil {
-			return err
-		}
-		defer r.Close()
-		if err := fs.Write(p, r, f.Size(), f.Mode()); err != nil {
-			return wrapError(err, opts.FileName)
-		}
-		// Update the file modification time to the one set in the archive.
-		if err := fs.Chtimes(p, f.ModTime(), f.ModTime()); err != nil {
-			return wrapError(err, opts.FileName)
-		}
-		return nil
+	return fs.extractStream(ctx, extractOptions{
+		dir:    dir,
+		format: format,
+		r:      input,
 	})
 }

server/filesystem/compress_test.go

@@ -1,54 +0,0 @@
-package filesystem
-
-import (
-	"context"
-	"os"
-	"testing"
-
-	. "github.com/franela/goblin"
-)
-
-// Given an archive named test.{ext}, with the following file structure:
-//
-//	test/
-//	|──inside/
-//	|────finside.txt
-//	|──outside.txt
-//
-// this test will ensure that it's being decompressed as expected
-func TestFilesystem_DecompressFile(t *testing.T) {
-	g := Goblin(t)
-	fs, rfs := NewFs()
-
-	g.Describe("Decompress", func() {
-		for _, ext := range []string{"zip", "rar", "tar", "tar.gz"} {
-			g.It("can decompress a "+ext, func() {
-				// copy the file to the new FS
-				c, err := os.ReadFile("./testdata/test." + ext)
-				g.Assert(err).IsNil()
-				err = rfs.CreateServerFile("./test."+ext, c)
-				g.Assert(err).IsNil()
-
-				// decompress
-				err = fs.DecompressFile(context.Background(), "/", "test."+ext)
-				g.Assert(err).IsNil()
-
-				// make sure everything is where it is supposed to be
-				_, err = rfs.StatServerFile("test/outside.txt")
-				g.Assert(err).IsNil()
-
-				st, err := rfs.StatServerFile("test/inside")
-				g.Assert(err).IsNil()
-				g.Assert(st.IsDir()).IsTrue()
-
-				_, err = rfs.StatServerFile("test/inside/finside.txt")
-				g.Assert(err).IsNil()
-				g.Assert(st.IsDir()).IsTrue()
-			})
-		}
-
-		g.AfterEach(func() {
-			_ = fs.TruncateRootDirectory()
-		})
-	})
-}

server/filesystem/disk_space.go

@@ -1,16 +1,17 @@
 package filesystem
 
 import (
-	"golang.org/x/sys/unix"
+	fs2 "io/fs"
+	"os"
+	"path/filepath"
 	"slices"
 	"sync"
 	"sync/atomic"
+	"syscall"
 	"time"
 
 	"emperror.dev/errors"
 	"github.com/apex/log"
-
-	"github.com/pterodactyl/wings/internal/ufs"
 )
 
 type SpaceCheckingOpts struct {
@@ -23,7 +24,7 @@ type usageLookupTime struct {
 	value time.Time
 }
 
-// Set sets the last time that a disk space lookup was performed.
+// Update the last time that a disk space lookup was performed.
 func (ult *usageLookupTime) Set(t time.Time) {
 	ult.Lock()
 	ult.value = t
@@ -41,12 +42,12 @@ func (ult *usageLookupTime) Get() time.Time {
 // MaxDisk returns the maximum amount of disk space that this Filesystem
 // instance is allowed to use.
 func (fs *Filesystem) MaxDisk() int64 {
-	return fs.unixFS.Limit()
+	return atomic.LoadInt64(&fs.diskLimit)
 }
 
 // SetDiskLimit sets the disk space limit for this Filesystem instance.
 func (fs *Filesystem) SetDiskLimit(i int64) {
-	fs.unixFS.SetLimit(i)
+	atomic.SwapInt64(&fs.diskLimit, i)
 }
 
 // The same concept as HasSpaceAvailable however this will return an error if there is
@@ -58,14 +59,13 @@ func (fs *Filesystem) HasSpaceErr(allowStaleValue bool) error {
 	return nil
 }
 
-// Determines if the directory a file is trying to be added to has enough space available
-// for the file to be written to.
+// HasSpaceAvailable checks if the directory a file is trying to be added to has enough
+// space available for the file to be written to. Because determining the amount of space
+// being used by a server is a taxing operation, we will load it all up into a cache and
+// pull from that as long as the key is not expired.
 //
-// Because determining the amount of space being used by a server is a taxing operation we
-// will load it all up into a cache and pull from that as long as the key is not expired.
-//
-// This operation will potentially block unless allowStaleValue is set to true. See the
-// documentation on DiskUsage for how this affects the call.
+// This operation will potentially be blocked unless allowStaleValue is set to true. See
+// the documentation on DiskUsage for how this affects the call.
 func (fs *Filesystem) HasSpaceAvailable(allowStaleValue bool) bool {
 	size, err := fs.DiskUsage(allowStaleValue)
 	if err != nil {
@@ -88,7 +88,7 @@ func (fs *Filesystem) HasSpaceAvailable(allowStaleValue bool) bool {
 // function for critical logical checks. It should only be used in areas where the actual disk usage
 // does not need to be perfect, e.g. API responses for server resource usage.
 func (fs *Filesystem) CachedUsage() int64 {
-	return fs.unixFS.Usage()
+	return atomic.LoadInt64(&fs.diskUsed)
 }
 
 // Internal helper function to allow other parts of the codebase to check the total used disk space
@@ -118,14 +118,14 @@ func (fs *Filesystem) DiskUsage(allowStaleValue bool) (int64, error) {
 			// currently performing a lookup, just do the disk usage calculation in the background.
 			go func(fs *Filesystem) {
 				if _, err := fs.updateCachedDiskUsage(); err != nil {
-					log.WithField("root", fs.Path()).WithField("error", err).Warn("failed to update fs disk usage from within routine")
+					log.WithField("root", fs.rootPath).WithField("error", err).Warn("failed to update fs disk usage from within routine")
 				}
 			}(fs)
 		}
 	}
 
 	// Return the currently cached value back to the calling function.
-	return fs.unixFS.Usage(), nil
+	return atomic.LoadInt64(&fs.diskUsed), nil
 }
 
 // Updates the currently used disk space for a server.
@@ -153,56 +153,77 @@ func (fs *Filesystem) updateCachedDiskUsage() (int64, error) {
 	// error encountered.
 	fs.lastLookupTime.Set(time.Now())
 
-	fs.unixFS.SetUsage(size)
+	atomic.StoreInt64(&fs.diskUsed, size)
 
 	return size, err
 }
 
-// DirectorySize calculates the size of a directory and its descendants.
-func (fs *Filesystem) DirectorySize(root string) (int64, error) {
-	dirfd, name, closeFd, err := fs.unixFS.SafePath(root)
-	defer closeFd()
-	if err != nil {
-		return 0, err
+// DirectorySize determines the directory size of a given location. Returns the size
+// in bytes. This can be a fairly taxing operation on locations with tons of files,
+// so it is recommended that you cache the output.
+func (fs *Filesystem) DirectorySize(dir string) (int64, error) {
+	dir = normalize(dir)
+	if dir != "." {
+		if _, err := fs.root.Lstat(dir); err != nil {
+			return 0, err
+		}
 	}
 
-	var hardLinks []uint64
-
-	var size atomic.Int64
-	err = fs.unixFS.WalkDirat(dirfd, name, func(dirfd int, name, _ string, d ufs.DirEntry, err error) error {
+	rt := fs.root
+	if dir != "." {
+		r, err := fs.root.OpenRoot(dir)
 		if err != nil {
-			return errors.Wrap(err, "walkdirat err")
+			return 0, errors.Wrap(err, "server/filesystem: directorysize: failed to open root directory")
 		}
+		defer r.Close()
+		rt = r
+	}
 
-		// Only calculate the size of regular files.
+	var size int64
+	var links []uint64
+
+	err := filepath.WalkDir(rt.Name(), func(path string, d fs2.DirEntry, err error) error {
 		if !d.Type().IsRegular() {
 			return nil
 		}
 
-		info, err := fs.unixFS.Lstatat(dirfd, name)
+		st, err := d.Info()
 		if err != nil {
-			return errors.Wrap(err, "lstatat err")
-		}
-
-		var sysFileInfo = info.Sys().(*unix.Stat_t)
-		if sysFileInfo.Nlink > 1 {
-			// Hard links have the same inode number
-			if slices.Contains(hardLinks, sysFileInfo.Ino) {
-				// Don't add hard links size twice
+			if errors.Is(err, os.ErrNotExist) {
 				return nil
-			} else {
-				hardLinks = append(hardLinks, sysFileInfo.Ino)
 			}
+			return err
 		}
 
-		size.Add(info.Size())
+		s := st.Sys().(*syscall.Stat_t)
+		if s.Nlink > 1 {
+			// Hard links have the same inode number, don't add them more than once.
+			if slices.Contains(links, s.Ino) {
+				return nil
+			}
+			links = append(links, s.Ino)
+		}
+
+		size += st.Size()
+
 		return nil
 	})
-	return size.Load(), errors.WrapIf(err, "server/filesystem: directorysize: failed to walk directory")
+
+	return size, errors.WrapIf(err, "server/filesystem: directorysize: failed to walk directory")
 }
 
+// Helper function to determine if a server has space available for a file of a given size.
+// If space is available, no error will be returned, otherwise an ErrNotEnoughSpace error
+// will be raised.
 func (fs *Filesystem) HasSpaceFor(size int64) error {
-	if !fs.unixFS.CanFit(size) {
+	if fs.MaxDisk() == 0 {
+		return nil
+	}
+	s, err := fs.DiskUsage(true)
+	if err != nil {
+		return err
+	}
+	if (s + size) > fs.MaxDisk() {
 		return newFilesystemError(ErrCodeDiskSpace, nil)
 	}
 	return nil
@@ -210,5 +231,24 @@ func (fs *Filesystem) HasSpaceFor(size int64) error {
 
 // Updates the disk usage for the Filesystem instance.
 func (fs *Filesystem) addDisk(i int64) int64 {
-	return fs.unixFS.Add(i)
+	size := atomic.LoadInt64(&fs.diskUsed)
+
+	// Sorry go gods. This is ugly but the best approach I can come up with for right
+	// now without completely re-evaluating the logic we use for determining disk space.
+	//
+	// Normally I would just be using the atomic load right below, but I'm not sure about
+	// the scenarios where it is 0 because nothing has run that would trigger a disk size
+	// calculation?
+	//
+	// Perhaps that isn't even a concern for the sake of this?
+	if !fs.isTest {
+		size, _ = fs.DiskUsage(true)
+	}
+
+	// If we're dropping below 0 somehow just cap it to 0.
+	if (size + i) < 0 {
+		return atomic.SwapInt64(&fs.diskUsed, 0)
+	}
+
+	return atomic.AddInt64(&fs.diskUsed, i)
 }

server/filesystem/errors.go

@@ -2,12 +2,10 @@ package filesystem
 
 import (
 	"fmt"
-	"path/filepath"
+	"os"
 
 	"emperror.dev/errors"
 	"github.com/apex/log"
-
-	"github.com/pterodactyl/wings/internal/ufs"
 )
 
 type ErrorCode string
@@ -16,7 +14,6 @@ const (
 	ErrCodeIsDirectory    ErrorCode = "E_ISDIR"
 	ErrCodeDiskSpace      ErrorCode = "E_NODISK"
 	ErrCodeUnknownArchive ErrorCode = "E_UNKNFMT"
-	ErrCodePathResolution ErrorCode = "E_BADPATH"
 	ErrCodeDenylistFile   ErrorCode = "E_DENYLIST"
 	ErrCodeUnknownError   ErrorCode = "E_UNKNOWN"
 	ErrNotExist           ErrorCode = "E_NOTEXIST"
@@ -64,12 +61,6 @@ func (e *Error) Error() string {
 			r = "<empty>"
 		}
 		return fmt.Sprintf("filesystem: file access prohibited: [%s] is on the denylist", r)
-	case ErrCodePathResolution:
-		r := e.resolved
-		if r == "" {
-			r = "<empty>"
-		}
-		return fmt.Sprintf("filesystem: server path [%s] resolves to a location outside the server root: %s", e.path, r)
 	case ErrNotExist:
 		return "filesystem: does not exist"
 	case ErrCodeUnknownError:
@@ -87,31 +78,7 @@ func (e *Error) Unwrap() error {
 
 // Generates an error logger instance with some basic information.
 func (fs *Filesystem) error(err error) *log.Entry {
-	return log.WithField("subsystem", "filesystem").WithField("root", fs.Path()).WithField("error", err)
-}
-
-// Handle errors encountered when walking through directories.
-//
-// If there is a path resolution error just skip the item entirely. Only return this for a
-// directory, otherwise return nil. Returning this error for a file will stop the walking
-// for the remainder of the directory. This is assuming an FileInfo struct was even returned.
-func (fs *Filesystem) handleWalkerError(err error, f ufs.FileInfo) error {
-	if !IsErrorCode(err, ErrCodePathResolution) {
-		return err
-	}
-	if f != nil && f.IsDir() {
-		return filepath.SkipDir
-	}
-	return nil
-}
-
-// IsFilesystemError checks if the given error is one of the Filesystem errors.
-func IsFilesystemError(err error) bool {
-	var fserr *Error
-	if err != nil && errors.As(err, &fserr) {
-		return true
-	}
-	return false
+	return log.WithField("subsystem", "filesystem").WithField("root", fs.root).WithField("error", err)
 }
 
 // IsErrorCode checks if "err" is a filesystem Error type. If so, it will then
@@ -125,17 +92,12 @@ func IsErrorCode(err error, code ErrorCode) bool {
 	return false
 }
 
-// NewBadPathResolution returns a new BadPathResolution error.
-func NewBadPathResolution(path string, resolved string) error {
-	return errors.WithStackDepth(&Error{code: ErrCodePathResolution, path: path, resolved: resolved}, 1)
+func IsPathError(err error) bool {
+	var pe *os.PathError
+	return errors.As(err, &pe)
 }
 
-// wrapError wraps the provided error as a Filesystem error and attaches the
-// provided resolved source to it. If the error is already a Filesystem error
-// no action is taken.
-func wrapError(err error, resolved string) error {
-	if err == nil || IsFilesystemError(err) {
-		return err
-	}
-	return errors.WithStackDepth(&Error{code: ErrCodeUnknownError, err: err, resolved: resolved}, 1)
+func IsLinkError(err error) bool {
+	var le *os.LinkError
+	return errors.As(err, &le)
 }

server/filesystem/errors_test.go

@@ -39,19 +39,4 @@ func TestFilesystem_PathResolutionError(t *testing.T) {
 			g.Assert(fserr.Unwrap()).Equal(underlying)
 		})
 	})
-
-	g.Describe("NewBadPathResolutionError", func() {
-		g.It("is can detect itself as an error correctly", func() {
-			err := NewBadPathResolution("foo", "bar")
-			g.Assert(IsErrorCode(err, ErrCodePathResolution)).IsTrue()
-			g.Assert(err.Error()).Equal("filesystem: server path [foo] resolves to a location outside the server root: bar")
-			g.Assert(IsErrorCode(&Error{code: ErrCodeIsDirectory}, ErrCodePathResolution)).IsFalse()
-		})
-
-		g.It("returns <empty> if no destination path is provided", func() {
-			err := NewBadPathResolution("foo", "")
-			g.Assert(err).IsNotNil()
-			g.Assert(err.Error()).Equal("filesystem: server path [foo] resolves to a location outside the server root: <empty>")
-		})
-	})
 }

server/filesystem/filesystem.go

@@ -1,15 +1,16 @@
 package filesystem
 
 import (
-	"fmt"
+	"bufio"
 	"io"
+	fs2 "io/fs"
 	"os"
+	"path"
 	"path/filepath"
-	"slices"
+	"sort"
 	"strconv"
 	"strings"
 	"sync"
-	"sync/atomic"
 	"time"
 
 	"emperror.dev/errors"
@@ -18,248 +19,257 @@ import (
 	ignore "github.com/sabhiram/go-gitignore"
 
 	"github.com/pterodactyl/wings/config"
-	"github.com/pterodactyl/wings/internal/ufs"
+	"github.com/pterodactyl/wings/system"
 )
 
 type Filesystem struct {
-	unixFS *ufs.Quota
-
 	mu                sync.RWMutex
 	lastLookupTime    *usageLookupTime
-	lookupInProgress  atomic.Bool
+	lookupInProgress  *system.AtomicBool
+	diskUsed          int64
 	diskCheckInterval time.Duration
 	denylist          *ignore.GitIgnore
 
+	// The maximum amount of disk space (in bytes) that this Filesystem instance can use.
+	diskLimit int64
+
+	// The root data directory path for this Filesystem instance.
+	root     *os.Root
+	rootPath string
+
 	isTest bool
 }
 
 // New creates a new Filesystem instance for a given server.
-func New(root string, size int64, denylist []string) (*Filesystem, error) {
-	if err := os.MkdirAll(root, 0o755); err != nil {
-		return nil, err
-	}
-	unixFS, err := ufs.NewUnixFS(root, config.UseOpenat2())
+func New(path string, size int64, denylist []string) (*Filesystem, error) {
+	r, err := os.OpenRoot(path)
 	if err != nil {
-		return nil, err
+		return nil, errors.Wrap(err, "server/filesystem: failed to open root")
 	}
-	quota := ufs.NewQuota(unixFS, size)
-
-	return &Filesystem{
-		unixFS: quota,
 
+	fs := &Filesystem{
+		root:              r,
+		rootPath:          path,
+		diskLimit:         size,
 		diskCheckInterval: time.Duration(config.Get().System.DiskCheckInterval),
 		lastLookupTime:    &usageLookupTime{},
+		lookupInProgress:  system.NewAtomicBool(false),
 		denylist:          ignore.CompileIgnoreLines(denylist...),
-	}, nil
+	}
+
+	return fs, nil
+}
+
+// normalize takes the input path, runs it through filepath.Clean and trims any
+// leading forward slashes (since the os.Root method calls will fail otherwise).
+// If the resulting path is an empty string, "." is returned which os.Root will
+// understand as the base directory.
+func normalize(path string) string {
+	c := strings.TrimLeft(filepath.Clean(path), string(filepath.Separator))
+	if c == "" {
+		return "."
+	}
+	return c
 }
 
 // Path returns the root path for the Filesystem instance.
 func (fs *Filesystem) Path() string {
-	return fs.unixFS.BasePath()
+	return fs.rootPath
 }
 
-// ReadDir reads directory entries.
-func (fs *Filesystem) ReadDir(path string) ([]ufs.DirEntry, error) {
-	return fs.unixFS.ReadDir(path)
-}
-
-// ReadDirStat is like ReadDir except that it returns FileInfo for each entry
-// instead of just a DirEntry.
-func (fs *Filesystem) ReadDirStat(path string) ([]ufs.FileInfo, error) {
-	return ufs.ReadDirMap(fs.unixFS.UnixFS, path, func(e ufs.DirEntry) (ufs.FileInfo, error) {
-		return e.Info()
-	})
+// Close closes the underlying os.Root instance for the server.
+func (fs *Filesystem) Close() error {
+	if err := fs.root.Close(); err != nil {
+		return errors.Wrap(err, "server/filesystem: failed to close root")
+	}
+	return nil
 }
 
 // File returns a reader for a file instance as well as the stat information.
-func (fs *Filesystem) File(p string) (ufs.File, Stat, error) {
-	f, err := fs.unixFS.Open(p)
+func (fs *Filesystem) File(p string) (*os.File, Stat, error) {
+	p = normalize(p)
+	st, err := fs.Stat(p)
 	if err != nil {
-		return nil, Stat{}, err
+		if errors.Is(err, os.ErrNotExist) {
+			return nil, Stat{}, newFilesystemError(ErrNotExist, err)
+		}
+		return nil, Stat{}, errors.WithStackIf(err)
 	}
-	st, err := statFromFile(f)
+	if st.IsDir() {
+		return nil, Stat{}, newFilesystemError(ErrCodeIsDirectory, nil)
+	}
+	f, err := fs.root.Open(p)
 	if err != nil {
-		_ = f.Close()
-		return nil, Stat{}, err
+		return nil, Stat{}, errors.WithStackIf(err)
 	}
 	return f, st, nil
 }
 
-func (fs *Filesystem) UnixFS() *ufs.UnixFS {
-	return fs.unixFS.UnixFS
-}
-
 // Touch acts by creating the given file and path on the disk if it is not present
-// already. If  it is present, the file is opened using the defaults which will truncate
+// already. If it is present, the file is opened using the defaults which will truncate
 // the contents. The opened file is then returned to the caller.
-func (fs *Filesystem) Touch(p string, flag int) (ufs.File, error) {
-	return fs.unixFS.Touch(p, flag, 0o644)
+func (fs *Filesystem) Touch(p string, flag int, mode os.FileMode) (*os.File, error) {
+	p = normalize(p)
+	o := &fileOpener{root: fs.root}
+	f, err := o.open(p, flag, mode)
+	if err == nil {
+		return f, nil
+	}
+	if f != nil {
+		_ = f.Close()
+	}
+	// If the error is not because it doesn't exist then we just need to bail at this point.
+	if !errors.Is(err, os.ErrNotExist) {
+		return nil, errors.Wrap(err, "server/filesystem: touch: failed to open file handle")
+	}
+	// Only create and chown the directory if it doesn't exist.
+	if _, err := fs.root.Stat(filepath.Dir(p)); errors.Is(err, os.ErrNotExist) {
+		// Create the path leading up to the file we're trying to create, setting the final perms
+		// on it as we go.
+		if err := fs.root.MkdirAll(filepath.Dir(p), 0o755); err != nil {
+			return nil, errors.WrapIf(err, "server/filesystem: touch: failed to create directory tree")
+		}
+		if err := fs.Chown(filepath.Dir(p)); err != nil {
+			return nil, errors.WrapIf(err, "server/filesystem: touch: failed to chown directory tree")
+		}
+	}
+	// Try to open the file now that we have created the pathing necessary for it, and then
+	// Chown that file so that the permissions don't mess with things.
+	f, err = o.open(p, flag, mode)
+	if err != nil {
+		return nil, errors.Wrap(err, "server/filesystem: touch: failed to open file handle")
+	}
+	_ = fs.Chown(p)
+	return f, nil
 }
 
 // Writefile writes a file to the system. If the file does not already exist one
 // will be created. This will also properly recalculate the disk space used by
 // the server when writing new files or modifying existing ones.
 //
-// DEPRECATED: use `Write` instead.
+// deprecated 1.12.1 prefer the use of Filesystem.Write()
 func (fs *Filesystem) Writefile(p string, r io.Reader) error {
+	p = normalize(p)
 	var currentSize int64
-	st, err := fs.unixFS.Stat(p)
-	if err != nil && !errors.Is(err, ufs.ErrNotExist) {
+	// If the file does not exist on the system already go ahead and create the pathway
+	// to it and an empty file. We'll then write to it later on after this completes.
+	stat, err := fs.root.Stat(p)
+	if err != nil && !os.IsNotExist(err) {
 		return errors.Wrap(err, "server/filesystem: writefile: failed to stat file")
 	} else if err == nil {
-		if st.IsDir() {
-			// TODO: resolved
-			return errors.WithStack(&Error{code: ErrCodeIsDirectory, resolved: ""})
+		if stat.IsDir() {
+			return errors.WithStack(&Error{code: ErrCodeIsDirectory, resolved: stat.Name()})
 		}
-		currentSize = st.Size()
-	}
-
-	// Touch the file and return the handle to it at this point. This will
-	// create or truncate the file, and create any necessary parent directories
-	// if they are missing.
-	file, err := fs.unixFS.Touch(p, ufs.O_RDWR|ufs.O_TRUNC, 0o644)
-	if err != nil {
-		return fmt.Errorf("error touching file: %w", err)
-	}
-	defer file.Close()
-
-	// Do not use CopyBuffer here, it is wasteful as the file implements
-	// io.ReaderFrom, which causes it to not use the buffer anyways.
-	n, err := io.Copy(file, r)
-
-	// Adjust the disk usage to account for the old size and the new size of the file.
-	fs.unixFS.Add(n - currentSize)
-
-	if err := fs.chownFile(p); err != nil {
-		return fmt.Errorf("error chowning file: %w", err)
-	}
-	// Return the error from io.Copy.
-	return err
-}
-
-func (fs *Filesystem) Write(p string, r io.Reader, newSize int64, mode ufs.FileMode) error {
-	var currentSize int64
-	st, err := fs.unixFS.Stat(p)
-	if err != nil && !errors.Is(err, ufs.ErrNotExist) {
-		return errors.Wrap(err, "server/filesystem: writefile: failed to stat file")
-	} else if err == nil {
-		if st.IsDir() {
-			// TODO: resolved
-			return errors.WithStack(&Error{code: ErrCodeIsDirectory, resolved: ""})
-		}
-		currentSize = st.Size()
+		currentSize = stat.Size()
 	}
 
+	br := bufio.NewReader(r)
 	// Check that the new size we're writing to the disk can fit. If there is currently
 	// a file we'll subtract that current file size from the size of the buffer to determine
 	// the amount of new data we're writing (or amount we're removing if smaller).
-	if err := fs.HasSpaceFor(newSize - currentSize); err != nil {
+	if err := fs.HasSpaceFor(int64(br.Size()) - currentSize); err != nil {
 		return err
 	}
 
-	// Touch the file and return the handle to it at this point. This will
-	// create or truncate the file, and create any necessary parent directories
-	// if they are missing.
-	file, err := fs.unixFS.Touch(p, ufs.O_RDWR|ufs.O_TRUNC, mode)
+	// Touch the file and return the handle to it at this point. This will create the file,
+	// any necessary directories, and set the proper owner of the file.
+	file, err := fs.Touch(p, os.O_RDWR|os.O_CREATE|os.O_TRUNC, 0o644)
 	if err != nil {
 		return err
 	}
 	defer file.Close()
 
-	if newSize == 0 {
-		// Subtract the previous size of the file if the new size is 0.
-		fs.unixFS.Add(-currentSize)
-	} else {
-		// Do not use CopyBuffer here, it is wasteful as the file implements
-		// io.ReaderFrom, which causes it to not use the buffer anyways.
-		var n int64
-		n, err = io.Copy(file, io.LimitReader(r, newSize))
+	buf := make([]byte, 1024*4)
+	sz, err := io.CopyBuffer(file, r, buf)
 
-		// Adjust the disk usage to account for the old size and the new size of the file.
-		fs.unixFS.Add(n - currentSize)
-	}
+	// Adjust the disk usage to account for the old size and the new size of the file.
+	fs.addDisk(sz - currentSize)
 
-	if err := fs.chownFile(p); err != nil {
-		return err
-	}
-	// Return any remaining error.
-	return err
+	return fs.Chown(p)
 }
 
-// CreateDirectory creates a new directory (name) at a specified path (p) for
-// the server.
-func (fs *Filesystem) CreateDirectory(name string, p string) error {
-	return fs.unixFS.MkdirAll(filepath.Join(p, name), 0o755)
-}
-
-func (fs *Filesystem) Rename(oldpath, newpath string) error {
-	return fs.unixFS.Rename(oldpath, newpath)
-}
-
-func (fs *Filesystem) Symlink(oldpath, newpath string) error {
-	return fs.unixFS.Symlink(oldpath, newpath)
-}
-
-func (fs *Filesystem) chownFile(name string) error {
-	if fs.isTest {
-		return nil
-	}
-
-	uid := config.Get().System.User.Uid
-	gid := config.Get().System.User.Gid
-	return fs.unixFS.Lchown(name, uid, gid)
-}
-
-// Chown recursively iterates over a file or directory and sets the permissions on all of the
-// underlying files. Iterate over all of the files and directories. If it is a file just
-// go ahead and perform the chown operation. Otherwise dig deeper into the directory until
-// we've run out of directories to dig into.
-func (fs *Filesystem) Chown(p string) error {
-	if fs.isTest {
-		return nil
-	}
-
-	uid := config.Get().System.User.Uid
-	gid := config.Get().System.User.Gid
-
-	dirfd, name, closeFd, err := fs.unixFS.SafePath(p)
-	defer closeFd()
-	if err != nil {
-		return err
-	}
-
-	// Start by just chowning the initial path that we received.
-	if err := fs.unixFS.Lchownat(dirfd, name, uid, gid); err != nil {
-		return errors.Wrap(err, "server/filesystem: chown: failed to chown path")
-	}
-
-	// If this is not a directory we can now return from the function, there is nothing
-	// left that we need to do.
-	if st, err := fs.unixFS.Lstatat(dirfd, name); err != nil || !st.IsDir() {
-		return nil
-	}
-
-	// This walker is probably some of the most efficient code in Wings. It has
-	// an internally re-used buffer for listing directory entries and doesn't
-	// need to check if every individual path it touches is safe as the code
-	// doesn't traverse symlinks, is immune to symlink timing attacks, and
-	// gives us a dirfd and file name to make a direct syscall with.
-	if err := fs.unixFS.WalkDirat(dirfd, name, func(dirfd int, name, _ string, info ufs.DirEntry, err error) error {
-		if err != nil {
-			return err
-		}
-		if err := fs.unixFS.Lchownat(dirfd, name, uid, gid); err != nil {
-			return err
-		}
-		return nil
-	}); err != nil {
-		return fmt.Errorf("server/filesystem: chown: failed to chown during walk function: %w", err)
+func (fs *Filesystem) Mkdir(p string, mode os.FileMode) error {
+	if err := fs.root.Mkdir(normalize(p), mode); err != nil {
+		return errors.Wrap(err, "server/filesystem: mkdir: failed to make directory")
 	}
 	return nil
 }
 
-func (fs *Filesystem) Chmod(path string, mode ufs.FileMode) error {
-	return fs.unixFS.Chmod(path, mode)
+// Write writes a file to the disk.
+func (fs *Filesystem) Write(p string, r io.Reader, newSize int64, mode os.FileMode) error {
+	st, err := fs.root.Stat(normalize(p))
+	if err != nil {
+		if !errors.Is(err, os.ErrNotExist) {
+			return errors.Wrap(err, "server/filesystem: write: failed to stat file")
+		}
+	}
+
+	var c int64
+	if err == nil {
+		if st.IsDir() {
+			return errors.WithStack(&Error{code: ErrCodeIsDirectory, resolved: normalize(p)})
+		}
+		c = st.Size()
+	}
+
+	if err := fs.HasSpaceFor(newSize - c); err != nil {
+		return err
+	}
+
+	f, err := fs.Touch(p, os.O_RDWR|os.O_CREATE|os.O_TRUNC, mode)
+	if err != nil {
+		return errors.Wrap(err, "server/filesystem: write: failed to touch file")
+	}
+	defer f.Close()
+
+	if newSize == 0 {
+		fs.addDisk(-c)
+	} else {
+		// Do not use CopyBuffer here; it is wasteful as the file implements
+		// io.ReaderFrom, which causes it to not use the buffer anyway.
+		n, err := io.Copy(f, io.LimitReader(r, newSize))
+		// Always adjust the disk to account for cases where a partial copy occurs
+		// and there is some new content on the disk.
+		fs.addDisk(n - c)
+		if err != nil {
+			return errors.Wrap(err, "server/filesystem: write: failed to write file")
+		}
+	}
+
+	// todo: might be unnecessary due to the `fs.Touch` call already doing this?
+	return fs.Chown(p)
+}
+
+// CreateDirectory creates a new directory ("name") at a specified path ("p") for the server.
+func (fs *Filesystem) CreateDirectory(name string, p string) error {
+	return fs.root.MkdirAll(path.Join(normalize(p), name), 0o755)
+}
+
+// Rename moves (or renames) a file or directory.
+func (fs *Filesystem) Rename(from string, to string) error {
+	to = normalize(to)
+	from = normalize(from)
+
+	if from == "." || to == "." {
+		return os.ErrExist
+	}
+
+	// If the target file or directory already exists the rename function will
+	// fail, so just bail out now.
+	if _, err := fs.root.Stat(to); err == nil {
+		return os.ErrExist
+	}
+
+	d := strings.TrimLeft(filepath.Dir(to), "/")
+	// Ensure that the directory we're moving into exists correctly on the system. Only do this if
+	// we're not at the root directory level.
+	if d != "" {
+		if err := fs.root.MkdirAll(d, 0o755); err != nil {
+			return errors.Wrap(err, "server/filesystem: failed to create directory tree")
+		}
+	}
+
+	return fs.root.Rename(from, to)
 }
 
 // Begin looping up to 50 times to try and create a unique copy file name. This will take
@@ -270,7 +280,7 @@ func (fs *Filesystem) Chmod(path string, mode ufs.FileMode) error {
 // Could probably make this more efficient by checking if there are any files matching the copy
 // pattern, and trying to find the highest number and then incrementing it by one rather than
 // looping endlessly.
-func (fs *Filesystem) findCopySuffix(dirfd int, name, extension string) (string, error) {
+func (fs *Filesystem) findCopySuffix(dir string, name string, extension string) (string, error) {
 	var i int
 	suffix := " copy"
 
@@ -282,10 +292,11 @@ func (fs *Filesystem) findCopySuffix(dirfd int, name, extension string) (string,
 		n := name + suffix + extension
 		// If we stat the file and it does not exist that means we're good to create the copy. If it
 		// does exist, we'll just continue to the next loop and try again.
-		if _, err := fs.unixFS.Lstatat(dirfd, n); err != nil {
-			if !errors.Is(err, ufs.ErrNotExist) {
+		if _, err := fs.Stat(path.Join(dir, n)); err != nil {
+			if !errors.Is(err, os.ErrNotExist) {
 				return "", err
 			}
+
 			break
 		}
 
@@ -297,201 +308,272 @@ func (fs *Filesystem) findCopySuffix(dirfd int, name, extension string) (string,
 	return name + suffix + extension, nil
 }
 
-// Copy copies a given file to the same location and appends a suffix to the
-// file to indicate that it has been copied.
+// Copies a given file to the same location and appends a suffix to the file to indicate that
+// it has been copied.
 func (fs *Filesystem) Copy(p string) error {
-	dirfd, name, closeFd, err := fs.unixFS.SafePath(p)
-	defer closeFd()
+	p = normalize(p)
+	s, err := fs.root.Stat(p)
 	if err != nil {
 		return err
-	}
-	source, err := fs.unixFS.OpenFileat(dirfd, name, ufs.O_RDONLY, 0)
-	if err != nil {
-		return err
-	}
-	defer source.Close()
-	info, err := source.Stat()
-	if err != nil {
-		return err
-	}
-	if info.IsDir() || !info.Mode().IsRegular() {
+	} else if s.IsDir() || !s.Mode().IsRegular() {
 		// If this is a directory or not a regular file, just throw a not-exist error
 		// since anything calling this function should understand what that means.
-		return ufs.ErrNotExist
+		return os.ErrNotExist
 	}
-	currentSize := info.Size()
 
 	// Check that copying this file wouldn't put the server over its limit.
-	if err := fs.HasSpaceFor(currentSize); err != nil {
+	if err := fs.HasSpaceFor(s.Size()); err != nil {
 		return err
 	}
 
-	base := info.Name()
+	base := filepath.Base(p)
+	relative := strings.TrimSuffix(strings.TrimPrefix(p, fs.Path()), base)
 	extension := filepath.Ext(base)
-	baseName := strings.TrimSuffix(base, extension)
+	name := strings.TrimSuffix(base, extension)
 
 	// Ensure that ".tar" is also counted as apart of the file extension.
 	// There might be a better way to handle this for other double file extensions,
 	// but this is a good workaround for now.
-	if strings.HasSuffix(baseName, ".tar") {
+	if strings.HasSuffix(name, ".tar") {
 		extension = ".tar" + extension
-		baseName = strings.TrimSuffix(baseName, ".tar")
+		name = strings.TrimSuffix(name, ".tar")
 	}
 
-	newName, err := fs.findCopySuffix(dirfd, baseName, extension)
+	source, err := fs.root.Open(p)
 	if err != nil {
 		return err
 	}
-	dst, err := fs.unixFS.OpenFileat(dirfd, newName, ufs.O_WRONLY|ufs.O_CREATE, info.Mode())
+	defer source.Close()
+
+	n, err := fs.findCopySuffix(relative, name, extension)
 	if err != nil {
 		return err
 	}
 
-	// Do not use CopyBuffer here, it is wasteful as the file implements
-	// io.ReaderFrom, which causes it to not use the buffer anyways.
-	n, err := io.Copy(dst, io.LimitReader(source, currentSize))
-	fs.unixFS.Add(n)
+	return fs.Writefile(path.Join(relative, n), source)
+}
 
-	if !fs.isTest {
-		if err := fs.unixFS.Lchownat(dirfd, newName, config.Get().System.User.Uid, config.Get().System.User.Gid); err != nil {
-			return err
-		}
+// Symlink creates a symbolic link between the source and target paths. [os.Root].Symlink
+// allows for the creation of a symlink that targets a file outside the root directory.
+// This isn't the end of the world because the read is blocked through this system, and
+// within a container it would just point to something in the readonly filesystem.
+//
+// There are also valid use-cases where a symlink might need to point to a file outside
+// the server data directory for a server to operate correctly. Since everything in the
+// filesystem runs through os.Root though we're protected from accidentally reading a
+// sensitive file on the _host_ OS.
+func (fs *Filesystem) Symlink(source, target string) error {
+	source = normalize(source)
+	target = normalize(target)
+
+	// os.Root#Symlink allows for the creation of a symlink that targets a file outside
+	// the root directory. This isn't the end of the world because the read is blocked
+	// through this system, and within a container it would just point to something in the
+	// readonly filesystem.
+	//
+	// However, just to avoid this propagating everywhere, *attempt* to block anything that
+	// would be pointing to a location outside the root directory.
+	if _, err := fs.root.Stat(source); err != nil {
+		return errors.Wrap(err, "server/filesystem: symlink: failed to stat source")
 	}
-	// Return the error from io.Copy.
-	return err
+
+	// Yes -- this gap between the stat and symlink allows a TOCTOU vulnerability to exist,
+	// but again we're layering this with the remaining logic that prevents this filesystem
+	// from reading any symlinks or acting on any file that points outside the root as defined
+	// by os.Root. The check above is mostly to prevent stupid mistakes or basic attempts to
+	// get around this. If someone *really* wants to make these symlinks, they can. They can
+	// also just create them from the running server process, and we still need to rely on our
+	// own internal FS logic to detect and block those reads, which it does. Therefore, I am
+	// not deeply concerned with this.
+	if err := fs.root.Symlink(source, target); err != nil {
+		return errors.Wrap(err, "server/filesystem: symlink: failed to create symlink")
+	}
+
+	return nil
+}
+
+// ReadDir returns all the contents of the given directory.
+func (fs *Filesystem) ReadDir(p string) ([]fs2.DirEntry, error) {
+	d, ok := fs.root.FS().(fs2.ReadDirFS)
+	if !ok {
+		return []fs2.DirEntry{}, errors.New("server/filesystem: readdir: could not init root fs")
+	}
+
+	e, err := d.ReadDir(normalize(p))
+	if err != nil {
+		return []fs2.DirEntry{}, errors.Wrap(err, "server/filesystem: readdir: failed to read directory")
+	}
+
+	return e, nil
 }
 
 // TruncateRootDirectory removes _all_ files and directories from a server's
 // data directory and resets the used disk space to zero.
 func (fs *Filesystem) TruncateRootDirectory() error {
-	if err := os.RemoveAll(fs.Path()); err != nil {
-		return err
-	}
-	if err := os.Mkdir(fs.Path(), 0o755); err != nil {
-		return err
-	}
-	_ = fs.unixFS.Close()
-	unixFS, err := ufs.NewUnixFS(fs.Path(), config.UseOpenat2())
+	err := filepath.WalkDir(fs.rootPath, func(path string, d fs2.DirEntry, err error) error {
+		p := normalize(strings.TrimPrefix(path, fs.rootPath))
+		if p == "." {
+			return nil
+		}
+
+		if err := fs.root.RemoveAll(p); err != nil {
+			return err
+		}
+
+		if d.IsDir() {
+			return filepath.SkipDir
+		}
+
+		return nil
+	})
+
 	if err != nil {
-		return err
+		go func() {
+			// If there was an error, re-calculate the disk usage right away to account
+			// for any partially removed files.
+			_, _ = fs.updateCachedDiskUsage()
+		}()
+
+		return errors.Wrap(err, "server/filesystem: truncate: failed to walk root directory")
 	}
-	var limit int64
-	if fs.isTest {
-		limit = 0
-	} else {
-		limit = fs.unixFS.Limit()
-	}
-	fs.unixFS = ufs.NewQuota(unixFS, limit)
+
+	// Set the disk space back to zero.
+	fs.addDisk(fs.diskUsed * -1)
+
 	return nil
 }
 
 // Delete removes a file or folder from the system. Prevents the user from
 // accidentally (or maliciously) removing their root server data directory.
 func (fs *Filesystem) Delete(p string) error {
-	return fs.unixFS.RemoveAll(p)
-}
-
-//type fileOpener struct {
-//	fs   *Filesystem
-//	busy uint
-//}
-//
-//// Attempts to open a given file up to "attempts" number of times, using a backoff. If the file
-//// cannot be opened because of a "text file busy" error, we will attempt until the number of attempts
-//// has been exhaused, at which point we will abort with an error.
-//func (fo *fileOpener) open(path string, flags int, perm ufs.FileMode) (ufs.File, error) {
-//	for {
-//		f, err := fo.fs.unixFS.OpenFile(path, flags, perm)
-//
-//		// If there is an error because the text file is busy, go ahead and sleep for a few
-//		// hundred milliseconds and then try again up to three times before just returning the
-//		// error back to the caller.
-//		//
-//		// Based on code from: https://github.com/golang/go/issues/22220#issuecomment-336458122
-//		if err != nil && fo.busy < 3 && strings.Contains(err.Error(), "text file busy") {
-//			time.Sleep(100 * time.Millisecond << fo.busy)
-//			fo.busy++
-//			continue
-//		}
-//
-//		return f, err
-//	}
-//}
-
-// ListDirectory lists the contents of a given directory and returns stat
-// information about each file and folder within it.
-func (fs *Filesystem) ListDirectory(p string) ([]Stat, error) {
-	// Read entries from the path on the filesystem, using the mapped reader, so
-	// we can map the DirEntry slice into a Stat slice with mimetype information.
-	out, err := ufs.ReadDirMap(fs.unixFS.UnixFS, p, func(e ufs.DirEntry) (Stat, error) {
-		info, err := e.Info()
-		if err != nil {
-			return Stat{}, err
-		}
-
-		var d string
-		if e.Type().IsDir() {
-			d = "inode/directory"
-		} else {
-			d = "application/octet-stream"
-		}
-		var m *mimetype.MIME
-		if e.Type().IsRegular() {
-			// TODO: I should probably find a better way to do this.
-			eO := e.(interface {
-				Open() (ufs.File, error)
-			})
-			f, err := eO.Open()
-			if err != nil {
-				return Stat{}, err
-			}
-			m, err = mimetype.DetectReader(f)
-			if err != nil {
-				log.Error(err.Error())
-			}
-			_ = f.Close()
-		}
-
-		st := Stat{FileInfo: info, Mimetype: d}
-		if m != nil {
-			st.Mimetype = m.String()
-		}
-		return st, nil
-	})
-	if err != nil {
-		return nil, err
+	p = normalize(p)
+	if p == "." {
+		return errors.New("server/filesystem: delete: cannot delete root directory")
 	}
 
-	// Sort entries alphabetically.
-	slices.SortStableFunc(out, func(a, b Stat) int {
-		switch {
-		case a.Name() == b.Name():
-			return 0
-		case a.Name() > b.Name():
-			return 1
-		default:
-			return -1
+	st, err := fs.root.Lstat(p)
+	if err != nil {
+		if os.IsNotExist(err) {
+			return nil
 		}
+		return errors.Wrap(err, "server/filesystem: delete: failed to stat file")
+	}
+
+	if st.IsDir() {
+		if s, err := fs.DirectorySize(p); err == nil {
+			fs.addDisk(-s)
+		}
+	} else {
+		fs.addDisk(-st.Size())
+	}
+
+	return fs.root.RemoveAll(p)
+}
+
+type fileOpener struct {
+	busy uint
+	root *os.Root
+}
+
+// Attempts to open a given file up to "attempts" number of times, using a backoff. If the file
+// cannot be opened because of a "text file busy" error, we will attempt until the number of attempts
+// has been exhaused, at which point we will abort with an error.
+func (fo *fileOpener) open(path string, flags int, mode os.FileMode) (*os.File, error) {
+	for {
+		f, err := fo.root.OpenFile(path, flags, mode)
+
+		// If there is an error because the text file is busy, go ahead and sleep for a few
+		// hundred milliseconds and then try again up to three times before just returning the
+		// error back to the caller.
+		//
+		// Based on code from: https://github.com/golang/go/issues/22220#issuecomment-336458122
+		if err != nil && fo.busy < 3 && strings.Contains(err.Error(), "text file busy") {
+			time.Sleep(100 * time.Millisecond << fo.busy)
+			fo.busy++
+			continue
+		}
+
+		return f, err
+	}
+}
+
+// ListDirectory lists the contents of a given directory and returns stat information
+// about each file and folder within it. If you only need to know the contents of the
+// directory and do not need mimetype information, call [Filesystem.ReadDir] directly
+// instead.
+func (fs *Filesystem) ListDirectory(p string) ([]Stat, error) {
+	files, err := fs.ReadDir(p)
+	if err != nil {
+		return []Stat{}, err
+	}
+
+	var wg sync.WaitGroup
+
+	// You must initialize the output of this directory as a non-nil value otherwise
+	// when it is marshaled into a JSON object you'll just get 'null' back, which will
+	// break the panel badly.
+	out := make([]Stat, len(files))
+
+	// Iterate over all the files and directories returned and perform an async process
+	// to get the mime-type for them all.
+	for i, file := range files {
+		wg.Add(1)
+
+		go func(idx int, d fs2.DirEntry) {
+			defer wg.Done()
+
+			fi, err := d.Info()
+			if err != nil {
+				log.WithField("error", err).WithField("path", filepath.Join(p, d.Name())).Warn("failed to retrieve directory entry info")
+				return
+			}
+
+			if fi.IsDir() {
+				out[idx] = Stat{FileInfo: fi, Mimetype: "inode/directory"}
+				return
+			}
+
+			st := Stat{FileInfo: fi, Mimetype: "application/octet-stream"}
+
+			// Don't try to detect the type on a pipe — this will just hang the application,
+			// and you'll never get a response back.
+			//
+			// @see https://github.com/pterodactyl/panel/issues/4059
+			if fi.Mode()&os.ModeNamedPipe == 0 {
+				if f, err := fs.root.Open(normalize(filepath.Join(p, d.Name()))); err != nil {
+					if !IsPathError(err) && !IsLinkError(err) {
+						log.WithField("error", err).WithField("path", filepath.Join(p, d.Name())).Warn("error opening file for mimetype detection")
+					}
+				} else {
+					if m, err := mimetype.DetectReader(f); err == nil {
+						st.Mimetype = m.String()
+					} else {
+						log.WithField("error", err).WithField("path", filepath.Join(p, d.Name())).Warn("failed to detect mimetype for file")
+					}
+					_ = f.Close()
+				}
+			}
+
+			out[idx] = st
+		}(i, file)
+	}
+
+	wg.Wait()
+
+	// Sort the output alphabetically to begin with since we've run the output
+	// through an asynchronous process and the order is gonna be very random.
+	sort.SliceStable(out, func(i, j int) bool {
+		if out[i].Name() == out[j].Name() || out[i].Name() > out[j].Name() {
+			return true
+		}
+		return false
 	})
 
-	// Sort folders before other file types.
-	slices.SortStableFunc(out, func(a, b Stat) int {
-		switch {
-		case a.IsDir() && b.IsDir():
-			return 0
-		case a.IsDir():
-			return -1
-		default:
-			return 1
-		}
+	// Then, sort it so that directories are listed first in the output. Everything
+	// will continue to be alphabetized at this point.
+	sort.SliceStable(out, func(i, j int) bool {
+		return out[i].IsDir()
 	})
 
 	return out, nil
 }
-
-func (fs *Filesystem) Chtimes(path string, atime, mtime time.Time) error {
-	if fs.isTest {
-		return nil
-	}
-	return fs.unixFS.Chtimes(path, atime, mtime)
-}

server/filesystem/filesystem_test.go

@@ -7,17 +7,22 @@ import (
 	"math/rand"
 	"os"
 	"path/filepath"
+	"strings"
+	"sync/atomic"
 	"testing"
 	"unicode/utf8"
 
 	. "github.com/franela/goblin"
 
-	"github.com/pterodactyl/wings/internal/ufs"
-
 	"github.com/pterodactyl/wings/config"
 )
 
-func NewFs() (*Filesystem, *rootFs) {
+type testFs struct {
+	*Filesystem
+	tmpDir string
+}
+
+func NewFs() *testFs {
 	config.Set(&config.Configuration{
 		AuthenticationToken: "abc",
 		System: config.SystemConfiguration{
@@ -29,32 +34,21 @@ func NewFs() (*Filesystem, *rootFs) {
 	tmpDir, err := os.MkdirTemp(os.TempDir(), "pterodactyl")
 	if err != nil {
 		panic(err)
-		return nil, nil
 	}
 
-	rfs := rootFs{root: tmpDir}
-
-	p := filepath.Join(tmpDir, "server")
-	if err := os.Mkdir(p, 0o755); err != nil {
+	fs, err := New(tmpDir, 0, []string{})
+	if err != nil {
 		panic(err)
-		return nil, nil
 	}
-
-	fs, _ := New(p, 0, []string{})
 	fs.isTest = true
-	if err := fs.TruncateRootDirectory(); err != nil {
-		panic(err)
-		return nil, nil
-	}
 
-	return fs, &rfs
+	tfs := &testFs{Filesystem: fs, tmpDir: tmpDir}
+	tfs.reset()
+
+	return tfs
 }
 
-type rootFs struct {
-	root string
-}
-
-func getFileContent(file ufs.File) string {
+func getFileContent(file *os.File) string {
 	var w bytes.Buffer
 	if _, err := bufio.NewReader(file).WriteTo(&w); err != nil {
 		panic(err)
@@ -62,40 +56,64 @@ func getFileContent(file ufs.File) string {
 	return w.String()
 }
 
-func (rfs *rootFs) CreateServerFile(p string, c []byte) error {
-	f, err := os.Create(filepath.Join(rfs.root, "server", p))
-
-	if err == nil {
-		_, _ = f.Write(c)
-		_ = f.Close()
+func (tfs *testFs) reset() {
+	if err := tfs.root.Close(); err != nil {
+		panic(err)
+	}
+	if !strings.HasPrefix(tfs.tmpDir, "/tmp/pterodactyl") {
+		panic("filesystem_test: attempting to delete outside root directory: " + tfs.tmpDir)
 	}
 
-	return err
+	if err := os.RemoveAll(tfs.tmpDir); err != nil {
+		if !os.IsNotExist(err) {
+			panic(err)
+		}
+	}
+
+	if !strings.HasPrefix(tfs.rootPath, tfs.tmpDir) {
+		panic("filesystem_test: mismatch between root and tmp paths")
+	}
+
+	tfs.rootPath = filepath.Join(tfs.tmpDir, "/server")
+	if err := os.MkdirAll(tfs.rootPath, 0o755); err != nil {
+		panic(err)
+	}
+
+	r, err := os.OpenRoot(tfs.rootPath)
+	if err != nil {
+		panic(err)
+	}
+
+	tfs.root = r
 }
 
-func (rfs *rootFs) CreateServerFileFromString(p string, c string) error {
-	return rfs.CreateServerFile(p, []byte(c))
-}
+func (tfs *testFs) write(name string, data []byte) {
+	p := filepath.Clean(filepath.Join(tfs.rootPath, name))
+	// Ensure we're always writing into a location that would also be cleaned up
+	// by the reset() function.
+	if !strings.HasPrefix(p, filepath.Dir(tfs.rootPath)) {
+		panic("filesystem_test: attempting to write outside of root directory: " + p)
+	}
 
-func (rfs *rootFs) StatServerFile(p string) (os.FileInfo, error) {
-	return os.Stat(filepath.Join(rfs.root, "server", p))
+	if err := os.WriteFile(filepath.Join(tfs.rootPath, name), data, 0o644); err != nil {
+		panic(err)
+	}
 }
 
 func TestFilesystem_Openfile(t *testing.T) {
 	g := Goblin(t)
-	fs, rfs := NewFs()
+	fs := NewFs()
 
 	g.Describe("File", func() {
 		g.It("returns custom error when file does not exist", func() {
 			_, _, err := fs.File("foo/bar.txt")
 
 			g.Assert(err).IsNotNil()
-			// TODO
-			//g.Assert(IsErrorCode(err, ErrNotExist)).IsTrue()
+			g.Assert(IsErrorCode(err, ErrNotExist)).IsTrue()
 		})
 
 		g.It("returns file stat information", func() {
-			_ = rfs.CreateServerFile("foo.txt", []byte("hello world"))
+			fs.write("foo.txt", []byte("hello world"))
 
 			f, st, err := fs.File("foo.txt")
 			g.Assert(err).IsNil()
@@ -106,14 +124,14 @@ func TestFilesystem_Openfile(t *testing.T) {
 		})
 
 		g.AfterEach(func() {
-			_ = fs.TruncateRootDirectory()
+			fs.reset()
 		})
 	})
 }
 
 func TestFilesystem_Writefile(t *testing.T) {
 	g := Goblin(t)
-	fs, _ := NewFs()
+	fs := NewFs()
 
 	g.Describe("Open and WriteFile", func() {
 		buf := &bytes.Buffer{}
@@ -123,22 +141,22 @@ func TestFilesystem_Writefile(t *testing.T) {
 		g.It("can create a new file", func() {
 			r := bytes.NewReader([]byte("test file content"))
 
-			g.Assert(fs.CachedUsage()).Equal(int64(0))
+			g.Assert(atomic.LoadInt64(&fs.diskUsed)).Equal(int64(0))
 
-			err := fs.Write("test.txt", r, r.Size(), 0o644)
+			err := fs.Writefile("test.txt", r)
 			g.Assert(err).IsNil()
 
 			f, _, err := fs.File("test.txt")
 			g.Assert(err).IsNil()
 			defer f.Close()
 			g.Assert(getFileContent(f)).Equal("test file content")
-			g.Assert(fs.CachedUsage()).Equal(r.Size())
+			g.Assert(atomic.LoadInt64(&fs.diskUsed)).Equal(r.Size())
 		})
 
 		g.It("can create a new file inside a nested directory with leading slash", func() {
 			r := bytes.NewReader([]byte("test file content"))
 
-			err := fs.Write("/some/nested/test.txt", r, r.Size(), 0o644)
+			err := fs.Writefile("/some/nested/test.txt", r)
 			g.Assert(err).IsNil()
 
 			f, _, err := fs.File("/some/nested/test.txt")
@@ -150,7 +168,7 @@ func TestFilesystem_Writefile(t *testing.T) {
 		g.It("can create a new file inside a nested directory without a trailing slash", func() {
 			r := bytes.NewReader([]byte("test file content"))
 
-			err := fs.Write("some/../foo/bar/test.txt", r, r.Size(), 0o644)
+			err := fs.Writefile("some/../foo/bar/test.txt", r)
 			g.Assert(err).IsNil()
 
 			f, _, err := fs.File("foo/bar/test.txt")
@@ -162,13 +180,17 @@ func TestFilesystem_Writefile(t *testing.T) {
 		g.It("cannot create a file outside the root directory", func() {
 			r := bytes.NewReader([]byte("test file content"))
 
-			err := fs.Write("/some/../foo/../../test.txt", r, r.Size(), 0o644)
+			err := fs.Writefile("../../etc/test.txt", r)
 			g.Assert(err).IsNotNil()
-			g.Assert(errors.Is(err, ufs.ErrBadPathResolution)).IsTrue("err is not ErrBadPathResolution")
+			g.Assert(IsPathError(err)).IsTrue()
+
+			err = fs.Writefile("a/../../../test.txt", r)
+			g.Assert(err).IsNotNil()
+			g.Assert(IsPathError(err)).IsTrue()
 		})
 
 		g.It("cannot write a file that exceeds the disk limits", func() {
-			fs.SetDiskLimit(1024)
+			atomic.StoreInt64(&fs.diskLimit, 1024)
 
 			b := make([]byte, 1025)
 			_, err := rand.Read(b)
@@ -176,18 +198,18 @@ func TestFilesystem_Writefile(t *testing.T) {
 			g.Assert(len(b)).Equal(1025)
 
 			r := bytes.NewReader(b)
-			err = fs.Write("test.txt", r, int64(len(b)), 0o644)
+			err = fs.Writefile("test.txt", r)
 			g.Assert(err).IsNotNil()
 			g.Assert(IsErrorCode(err, ErrCodeDiskSpace)).IsTrue()
 		})
 
 		g.It("truncates the file when writing new contents", func() {
 			r := bytes.NewReader([]byte("original data"))
-			err := fs.Write("test.txt", r, r.Size(), 0o644)
+			err := fs.Writefile("test.txt", r)
 			g.Assert(err).IsNil()
 
 			r = bytes.NewReader([]byte("new data"))
-			err = fs.Write("test.txt", r, r.Size(), 0o644)
+			err = fs.Writefile("test.txt", r)
 			g.Assert(err).IsNil()
 
 			f, _, err := fs.File("test.txt")
@@ -198,21 +220,24 @@ func TestFilesystem_Writefile(t *testing.T) {
 
 		g.AfterEach(func() {
 			buf.Truncate(0)
-			_ = fs.TruncateRootDirectory()
+			fs.reset()
+
+			atomic.StoreInt64(&fs.diskUsed, 0)
+			atomic.StoreInt64(&fs.diskLimit, 0)
 		})
 	})
 }
 
 func TestFilesystem_CreateDirectory(t *testing.T) {
 	g := Goblin(t)
-	fs, rfs := NewFs()
+	fs := NewFs()
 
 	g.Describe("CreateDirectory", func() {
 		g.It("should create missing directories automatically", func() {
 			err := fs.CreateDirectory("test", "foo/bar/baz")
 			g.Assert(err).IsNil()
 
-			st, err := rfs.StatServerFile("foo/bar/baz/test")
+			st, err := os.Stat(filepath.Join(fs.rootPath, "foo/bar/baz/test"))
 			g.Assert(err).IsNil()
 			g.Assert(st.IsDir()).IsTrue()
 			g.Assert(st.Name()).Equal("test")
@@ -222,7 +247,7 @@ func TestFilesystem_CreateDirectory(t *testing.T) {
 			err := fs.CreateDirectory("test", "/foozie/barzie/bazzy/")
 			g.Assert(err).IsNil()
 
-			st, err := rfs.StatServerFile("foozie/barzie/bazzy/test")
+			st, err := os.Stat(filepath.Join(fs.rootPath, "foozie/barzie/bazzy/test"))
 			g.Assert(err).IsNil()
 			g.Assert(st.IsDir()).IsTrue()
 			g.Assert(st.Name()).Equal("test")
@@ -231,93 +256,89 @@ func TestFilesystem_CreateDirectory(t *testing.T) {
 		g.It("should not allow the creation of directories outside the root", func() {
 			err := fs.CreateDirectory("test", "e/../../something")
 			g.Assert(err).IsNotNil()
-			g.Assert(errors.Is(err, ufs.ErrBadPathResolution)).IsTrue("err is not ErrBadPathResolution")
+			g.Assert(IsPathError(err)).IsTrue()
 		})
 
 		g.It("should not increment the disk usage", func() {
 			err := fs.CreateDirectory("test", "/")
 			g.Assert(err).IsNil()
-			g.Assert(fs.CachedUsage()).Equal(int64(0))
+			g.Assert(atomic.LoadInt64(&fs.diskUsed)).Equal(int64(0))
 		})
 
 		g.AfterEach(func() {
-			_ = fs.TruncateRootDirectory()
+			fs.reset()
 		})
 	})
 }
 
 func TestFilesystem_Rename(t *testing.T) {
 	g := Goblin(t)
-	fs, rfs := NewFs()
+	fs := NewFs()
 
 	g.Describe("Rename", func() {
 		g.BeforeEach(func() {
-			if err := rfs.CreateServerFileFromString("source.txt", "text content"); err != nil {
-				panic(err)
-			}
+			fs.write("source.txt", []byte("text content"))
 		})
 
 		g.It("returns an error if the target already exists", func() {
-			err := rfs.CreateServerFileFromString("target.txt", "taget content")
-			g.Assert(err).IsNil()
+			fs.write("target.txt", []byte("taget content"))
 
-			err = fs.Rename("source.txt", "target.txt")
+			err := fs.Rename("source.txt", "target.txt")
 			g.Assert(err).IsNotNil()
-			g.Assert(errors.Is(err, ufs.ErrExist)).IsTrue("err is not ErrExist")
+			g.Assert(errors.Is(err, os.ErrExist)).IsTrue()
 		})
 
 		g.It("returns an error if the final destination is the root directory", func() {
 			err := fs.Rename("source.txt", "/")
 			g.Assert(err).IsNotNil()
-			g.Assert(errors.Is(err, ufs.ErrBadPathResolution)).IsTrue("err is not ErrBadPathResolution")
+			g.Assert(errors.Is(err, os.ErrExist)).IsTrue()
 		})
 
 		g.It("returns an error if the source destination is the root directory", func() {
-			err := fs.Rename("/", "target.txt")
+			err := fs.Rename("/", "destination.txt")
 			g.Assert(err).IsNotNil()
-			g.Assert(errors.Is(err, ufs.ErrBadPathResolution)).IsTrue("err is not ErrBadPathResolution")
+			g.Assert(errors.Is(err, os.ErrExist)).IsTrue()
 		})
 
 		g.It("does not allow renaming to a location outside the root", func() {
 			err := fs.Rename("source.txt", "../target.txt")
 			g.Assert(err).IsNotNil()
-			g.Assert(errors.Is(err, ufs.ErrBadPathResolution)).IsTrue("err is not ErrBadPathResolution")
+			g.Assert(IsPathError(err)).IsTrue()
 		})
 
 		g.It("does not allow renaming from a location outside the root", func() {
-			err := rfs.CreateServerFileFromString("/../ext-source.txt", "taget content")
-
-			err = fs.Rename("/../ext-source.txt", "target.txt")
+			err := fs.Rename("../ext-source.txt", "target.txt")
 			g.Assert(err).IsNotNil()
-			g.Assert(errors.Is(err, ufs.ErrBadPathResolution)).IsTrue("err is not ErrBadPathResolution")
+			g.Assert(IsLinkError(err)).IsTrue()
 		})
 
 		g.It("allows a file to be renamed", func() {
 			err := fs.Rename("source.txt", "target.txt")
 			g.Assert(err).IsNil()
 
-			_, err = rfs.StatServerFile("source.txt")
+			_, err = os.Stat(filepath.Join(fs.rootPath, "source.txt"))
 			g.Assert(err).IsNotNil()
-			g.Assert(errors.Is(err, ufs.ErrNotExist)).IsTrue("err is not ErrNotExist")
+			g.Assert(errors.Is(err, os.ErrNotExist)).IsTrue()
 
-			st, err := rfs.StatServerFile("target.txt")
+			st, err := os.Stat(filepath.Join(fs.rootPath, "target.txt"))
 			g.Assert(err).IsNil()
 			g.Assert(st.Name()).Equal("target.txt")
 			g.Assert(st.Size()).IsNotZero()
 		})
 
 		g.It("allows a folder to be renamed", func() {
-			err := os.Mkdir(filepath.Join(rfs.root, "/server/source_dir"), 0o755)
+			if err := os.Mkdir(filepath.Join(fs.rootPath, "/source_dir"), 0o755); err != nil {
+				panic(err)
+			}
+
+			err := fs.Rename("source_dir", "target_dir")
 			g.Assert(err).IsNil()
 
-			err = fs.Rename("source_dir", "target_dir")
-			g.Assert(err).IsNil()
-
-			_, err = rfs.StatServerFile("source_dir")
+			_, err = os.Stat(filepath.Join(fs.rootPath, "source_dir"))
 			g.Assert(err).IsNotNil()
-			g.Assert(errors.Is(err, ufs.ErrNotExist)).IsTrue("err is not ErrNotExist")
+			g.Assert(errors.Is(err, os.ErrNotExist)).IsTrue()
 
-			st, err := rfs.StatServerFile("target_dir")
+			st, err := os.Stat(filepath.Join(fs.rootPath, "target_dir"))
 			g.Assert(err).IsNil()
 			g.Assert(st.IsDir()).IsTrue()
 		})
@@ -325,92 +346,81 @@ func TestFilesystem_Rename(t *testing.T) {
 		g.It("returns an error if the source does not exist", func() {
 			err := fs.Rename("missing.txt", "target.txt")
 			g.Assert(err).IsNotNil()
-			g.Assert(errors.Is(err, ufs.ErrNotExist)).IsTrue("err is not ErrNotExist")
+			g.Assert(errors.Is(err, os.ErrNotExist)).IsTrue()
 		})
 
 		g.It("creates directories if they are missing", func() {
 			err := fs.Rename("source.txt", "nested/folder/target.txt")
 			g.Assert(err).IsNil()
 
-			st, err := rfs.StatServerFile("nested/folder/target.txt")
+			st, err := os.Stat(filepath.Join(fs.rootPath, "nested/folder/target.txt"))
 			g.Assert(err).IsNil()
 			g.Assert(st.Name()).Equal("target.txt")
 		})
 
 		g.AfterEach(func() {
-			_ = fs.TruncateRootDirectory()
+			fs.reset()
 		})
 	})
 }
 
 func TestFilesystem_Copy(t *testing.T) {
 	g := Goblin(t)
-	fs, rfs := NewFs()
+	fs := NewFs()
 
 	g.Describe("Copy", func() {
 		g.BeforeEach(func() {
-			if err := rfs.CreateServerFileFromString("source.txt", "text content"); err != nil {
-				panic(err)
-			}
-
-			fs.unixFS.SetUsage(int64(utf8.RuneCountInString("test content")))
+			fs.write("source.txt", []byte("text content"))
+			atomic.StoreInt64(&fs.diskUsed, int64(utf8.RuneCountInString("test content")))
 		})
 
 		g.It("should return an error if the source does not exist", func() {
 			err := fs.Copy("foo.txt")
 			g.Assert(err).IsNotNil()
-			g.Assert(errors.Is(err, ufs.ErrNotExist)).IsTrue("err is not ErrNotExist")
+			g.Assert(errors.Is(err, os.ErrNotExist)).IsTrue()
 		})
 
 		g.It("should return an error if the source is outside the root", func() {
-			err := rfs.CreateServerFileFromString("/../ext-source.txt", "text content")
-
-			err = fs.Copy("../ext-source.txt")
+			err := fs.Copy("../ext-source.txt")
 			g.Assert(err).IsNotNil()
-			g.Assert(errors.Is(err, ufs.ErrBadPathResolution)).IsTrue("err is not ErrBadPathResolution")
+			g.Assert(IsPathError(err)).IsTrue()
 		})
 
 		g.It("should return an error if the source directory is outside the root", func() {
-			err := os.MkdirAll(filepath.Join(rfs.root, "nested/in/dir"), 0o755)
-			g.Assert(err).IsNil()
-
-			err = rfs.CreateServerFileFromString("/../nested/in/dir/ext-source.txt", "external content")
-			g.Assert(err).IsNil()
-
-			err = fs.Copy("../nested/in/dir/ext-source.txt")
+			err := fs.Copy("../nested/in/dir/ext-source.txt")
 			g.Assert(err).IsNotNil()
-			g.Assert(errors.Is(err, ufs.ErrBadPathResolution)).IsTrue("err is not ErrBadPathResolution")
+			g.Assert(IsPathError(err)).IsTrue()
 
 			err = fs.Copy("nested/in/../../../nested/in/dir/ext-source.txt")
 			g.Assert(err).IsNotNil()
-			g.Assert(errors.Is(err, ufs.ErrBadPathResolution)).IsTrue("err is not ErrBadPathResolution")
+			g.Assert(IsPathError(err)).IsTrue()
 		})
 
 		g.It("should return an error if the source is a directory", func() {
-			err := os.Mkdir(filepath.Join(rfs.root, "server/dir"), 0o755)
+			err := os.Mkdir(filepath.Join(fs.rootPath, "/dir"), 0o755)
 			g.Assert(err).IsNil()
 
 			err = fs.Copy("dir")
 			g.Assert(err).IsNotNil()
-			g.Assert(errors.Is(err, ufs.ErrNotExist)).IsTrue("err is not ErrNotExist")
+			g.Assert(errors.Is(err, os.ErrNotExist)).IsTrue()
 		})
 
 		g.It("should return an error if there is not space to copy the file", func() {
-			fs.SetDiskLimit(2)
+			atomic.StoreInt64(&fs.diskLimit, 2)
 
 			err := fs.Copy("source.txt")
 			g.Assert(err).IsNotNil()
-			g.Assert(IsErrorCode(err, ErrCodeDiskSpace)).IsTrue("err is not ErrCodeDiskSpace")
+			g.Assert(IsErrorCode(err, ErrCodeDiskSpace)).IsTrue()
 		})
 
 		g.It("should create a copy of the file and increment the disk used", func() {
 			err := fs.Copy("source.txt")
 			g.Assert(err).IsNil()
 
-			_, err = rfs.StatServerFile("source.txt")
+			_, err = os.Stat(filepath.Join(fs.rootPath, "source.txt"))
 			g.Assert(err).IsNil()
 
-			_, err = rfs.StatServerFile("source copy.txt")
+			_, err = os.Stat(filepath.Join(fs.rootPath, "source copy.txt"))
 			g.Assert(err).IsNil()
 		})
 
@@ -424,68 +434,148 @@ func TestFilesystem_Copy(t *testing.T) {
 			r := []string{"source.txt", "source copy.txt", "source copy 1.txt"}
 
 			for _, name := range r {
-				_, err = rfs.StatServerFile(name)
+				_, err = os.Stat(filepath.Join(fs.rootPath, name))
 				g.Assert(err).IsNil()
 			}
 
-			g.Assert(fs.CachedUsage()).Equal(int64(utf8.RuneCountInString("test content")) * 3)
+			g.Assert(atomic.LoadInt64(&fs.diskUsed)).Equal(int64(utf8.RuneCountInString("test content")) * 3)
 		})
 
 		g.It("should create a copy inside of a directory", func() {
-			err := os.MkdirAll(filepath.Join(rfs.root, "/server/nested/in/dir"), 0o755)
+			if err := os.MkdirAll(filepath.Join(fs.rootPath, "/nested/in/dir"), 0o755); err != nil {
+				panic(err)
+			}
+
+			fs.write("nested/in/dir/source.txt", []byte("test content"))
+
+			err := fs.Copy("nested/in/dir/source.txt")
 			g.Assert(err).IsNil()
 
-			err = rfs.CreateServerFileFromString("nested/in/dir/source.txt", "test content")
+			_, err = os.Stat(filepath.Join(fs.rootPath, "nested/in/dir/source.txt"))
 			g.Assert(err).IsNil()
 
-			err = fs.Copy("nested/in/dir/source.txt")
-			g.Assert(err).IsNil()
-
-			_, err = rfs.StatServerFile("nested/in/dir/source.txt")
-			g.Assert(err).IsNil()
-
-			_, err = rfs.StatServerFile("nested/in/dir/source copy.txt")
+			_, err = os.Stat(filepath.Join(fs.rootPath, "nested/in/dir/source copy.txt"))
 			g.Assert(err).IsNil()
 		})
 
 		g.AfterEach(func() {
-			_ = fs.TruncateRootDirectory()
+			fs.reset()
+
+			atomic.StoreInt64(&fs.diskUsed, 0)
+			atomic.StoreInt64(&fs.diskLimit, 0)
+		})
+	})
+}
+
+func TestFilesystem_Symlink(t *testing.T) {
+	g := Goblin(t)
+	fs := NewFs()
+
+	g.Describe("Symlink", func() {
+		g.It("should create a symlink", func() {
+			fs.write("source.txt", []byte("text content"))
+
+			err := fs.Symlink("source.txt", "symlink.txt")
+			g.Assert(err).IsNil()
+
+			st, err := os.Lstat(filepath.Join(fs.rootPath, "symlink.txt"))
+			g.Assert(err).IsNil()
+			g.Assert(st.Mode()&os.ModeSymlink != 0).IsTrue()
+		})
+
+		g.It("should return an error if the source is outside the root", func() {
+			err := fs.Symlink("../source.txt", "symlink.txt")
+			g.Assert(err).IsNotNil()
+			g.Assert(IsPathError(err)).IsTrue()
+		})
+
+		g.It("should return an error if the dest is outside the root", func() {
+			fs.write("source.txt", []byte("text content"))
+
+			err := fs.Symlink("source.txt", "../symlink.txt")
+			g.Assert(err).IsNotNil()
+			g.Assert(IsLinkError(err)).IsTrue()
+		})
+
+		g.AfterEach(func() {
+			fs.reset()
+		})
+	})
+}
+
+func TestFilesystem_ReadDir(t *testing.T) {
+	g := Goblin(t)
+	fs := NewFs()
+
+	g.Describe("ReadDir", func() {
+		g.Before(func() {
+			if err := os.Mkdir(filepath.Join(fs.rootPath, "child"), 0o755); err != nil {
+				panic(err)
+			}
+
+			fs.write("one.txt", []byte("one"))
+			fs.write("two.txt", []byte("two"))
+			fs.write("child/three.txt", []byte("two"))
+		})
+
+		g.After(func() {
+			fs.reset()
+		})
+
+		g.It("should return the contents of the root directory", func() {
+			d, err := fs.ReadDir("/")
+			g.Assert(err).IsNil()
+			g.Assert(len(d)).Equal(3)
+
+			// os.Root#ReadDir sorts them by name.
+			g.Assert(d[0].Name()).Equal("child")
+			g.Assert(d[0].IsDir()).IsTrue()
+			g.Assert(d[1].Name()).Equal("one.txt")
+			g.Assert(d[2].Name()).Equal("two.txt")
+		})
+
+		g.It("should return the contents of a child directory", func() {
+			d, err := fs.ReadDir("child")
+			g.Assert(err).IsNil()
+			g.Assert(len(d)).Equal(1)
+			g.Assert(d[0].Name()).Equal("three.txt")
+		})
+
+		g.It("should return an error if the directory is outside the root", func() {
+			_, err := fs.ReadDir("../server")
+			g.Assert(err).IsNotNil()
+			g.Assert(IsPathError(err)).IsTrue()
 		})
 	})
 }
 
 func TestFilesystem_Delete(t *testing.T) {
 	g := Goblin(t)
-	fs, rfs := NewFs()
+	fs := NewFs()
 
 	g.Describe("Delete", func() {
 		g.BeforeEach(func() {
-			if err := rfs.CreateServerFileFromString("source.txt", "test content"); err != nil {
-				panic(err)
-			}
-
-			fs.unixFS.SetUsage(int64(utf8.RuneCountInString("test content")))
+			fs.write("source.txt", []byte("text content"))
+			atomic.StoreInt64(&fs.diskUsed, int64(utf8.RuneCountInString("test content")))
 		})
 
 		g.It("does not delete files outside the root directory", func() {
-			err := rfs.CreateServerFileFromString("/../ext-source.txt", "external content")
-
-			err = fs.Delete("../ext-source.txt")
+			err := fs.Delete("../ext-source.txt")
 			g.Assert(err).IsNotNil()
-			g.Assert(errors.Is(err, ufs.ErrBadPathResolution)).IsTrue("err is not ErrBadPathResolution")
+			g.Assert(IsPathError(err)).IsTrue()
 		})
 
 		g.It("does not allow the deletion of the root directory", func() {
 			err := fs.Delete("/")
 			g.Assert(err).IsNotNil()
-			g.Assert(errors.Is(err, ufs.ErrBadPathResolution)).IsTrue("err is not ErrBadPathResolution")
+			g.Assert(err.Error()).Equal("server/filesystem: delete: cannot delete root directory")
 		})
 
 		g.It("does not return an error if the target does not exist", func() {
 			err := fs.Delete("missing.txt")
 			g.Assert(err).IsNil()
 
-			st, err := rfs.StatServerFile("source.txt")
+			st, err := os.Stat(filepath.Join(fs.rootPath, "source.txt"))
 			g.Assert(err).IsNil()
 			g.Assert(st.Name()).Equal("source.txt")
 		})
@@ -494,11 +584,11 @@ func TestFilesystem_Delete(t *testing.T) {
 			err := fs.Delete("source.txt")
 			g.Assert(err).IsNil()
 
-			_, err = rfs.StatServerFile("source.txt")
+			_, err = os.Stat(filepath.Join(fs.rootPath, "source.txt"))
 			g.Assert(err).IsNotNil()
-			g.Assert(errors.Is(err, ufs.ErrNotExist)).IsTrue("err is not ErrNotExist")
+			g.Assert(errors.Is(err, os.ErrNotExist)).IsTrue()
 
-			g.Assert(fs.CachedUsage()).Equal(int64(0))
+			g.Assert(atomic.LoadInt64(&fs.diskUsed)).Equal(int64(0))
 		})
 
 		g.It("deletes all items inside a directory if the directory is deleted", func() {
@@ -508,103 +598,109 @@ func TestFilesystem_Delete(t *testing.T) {
 				"foo/bar/baz/source.txt",
 			}
 
-			err := os.MkdirAll(filepath.Join(rfs.root, "/server/foo/bar/baz"), 0o755)
-			g.Assert(err).IsNil()
-
-			for _, s := range sources {
-				err = rfs.CreateServerFileFromString(s, "test content")
-				g.Assert(err).IsNil()
+			if err := os.MkdirAll(filepath.Join(fs.rootPath, "/foo/bar/baz"), 0o755); err != nil {
+				panic(err)
 			}
 
-			fs.unixFS.SetUsage(int64(utf8.RuneCountInString("test content") * 3))
+			for _, s := range sources {
+				fs.write(s, []byte("test content"))
+			}
 
-			err = fs.Delete("foo")
+			atomic.StoreInt64(&fs.diskUsed, int64(utf8.RuneCountInString("test content")*3))
+
+			err := fs.Delete("foo")
 			g.Assert(err).IsNil()
-			g.Assert(fs.unixFS.Usage()).Equal(int64(0))
+			g.Assert(atomic.LoadInt64(&fs.diskUsed)).Equal(int64(0))
 
 			for _, s := range sources {
-				_, err = rfs.StatServerFile(s)
+				_, err = os.Stat(filepath.Join(fs.rootPath, s))
 				g.Assert(err).IsNotNil()
-				g.Assert(errors.Is(err, ufs.ErrNotExist)).IsTrue("err is not ErrNotExist")
+				g.Assert(errors.Is(err, os.ErrNotExist)).IsTrue()
 			}
 		})
 
 		g.It("deletes a symlink but not it's target within the root directory", func() {
-			// Symlink to a file inside the root directory.
-			err := os.Symlink(filepath.Join(rfs.root, "server/source.txt"), filepath.Join(rfs.root, "server/symlink.txt"))
-			g.Assert(err).IsNil()
+			// Symlink to a file inside the root server data directory.
+			if err := os.Symlink(filepath.Join(fs.rootPath, "source.txt"), filepath.Join(fs.rootPath, "symlink.txt")); err != nil {
+				panic(err)
+			}
 
 			// Delete the symlink itself.
-			err = fs.Delete("symlink.txt")
+			err := fs.Delete("symlink.txt")
 			g.Assert(err).IsNil()
 
 			// Ensure the symlink was deleted.
-			_, err = os.Lstat(filepath.Join(rfs.root, "server/symlink.txt"))
+			_, err = os.Lstat(filepath.Join(fs.rootPath, "symlink.txt"))
 			g.Assert(err).IsNotNil()
 
 			// Ensure the symlink target still exists.
-			_, err = os.Lstat(filepath.Join(rfs.root, "server/source.txt"))
+			_, err = os.Lstat(filepath.Join(fs.rootPath, "source.txt"))
 			g.Assert(err).IsNil()
 		})
 
 		g.It("does not delete files symlinked outside of the root directory", func() {
 			// Create a file outside the root directory.
-			err := rfs.CreateServerFileFromString("/../source.txt", "test content")
-			g.Assert(err).IsNil()
+			fs.write("../external.txt", []byte("test content"))
 
 			// Create a symlink to the file outside the root directory.
-			err = os.Symlink(filepath.Join(rfs.root, "source.txt"), filepath.Join(rfs.root, "/server/symlink.txt"))
-			g.Assert(err).IsNil()
+			if err := os.Symlink(filepath.Join(fs.rootPath, "../external.txt"), filepath.Join(fs.rootPath, "symlink.txt")); err != nil {
+				panic(err)
+			}
 
-			// Delete the symlink. (This should pass as we will delete the symlink itself, not it's target)
-			err = fs.Delete("symlink.txt")
+			// Delete the symlink. (This should pass as we will delete the symlink itself, not the target)
+			err := fs.Delete("symlink.txt")
 			g.Assert(err).IsNil()
 
 			// Ensure the file outside the root directory still exists.
-			_, err = os.Lstat(filepath.Join(rfs.root, "source.txt"))
+			_, err = os.Lstat(filepath.Join(fs.rootPath, "../external.txt"))
 			g.Assert(err).IsNil()
 		})
 
 		g.It("does not delete files symlinked through a directory outside of the root directory", func() {
 			// Create a directory outside the root directory.
-			err := os.Mkdir(filepath.Join(rfs.root, "foo"), 0o755)
-			g.Assert(err).IsNil()
+			if err := os.Mkdir(filepath.Join(fs.rootPath, "../external"), 0o755); err != nil {
+				panic(err)
+			}
 
-			// Create a file inside the directory that is outside the root.
-			err = rfs.CreateServerFileFromString("/../foo/source.txt", "test content")
-			g.Assert(err).IsNil()
+			fs.write("../external/source.txt", []byte("test content"))
 
 			// Symlink the directory that is outside the root to a file inside the root.
-			err = os.Symlink(filepath.Join(rfs.root, "foo"), filepath.Join(rfs.root, "server/symlink"))
-			g.Assert(err).IsNil()
+			if err := os.Symlink(filepath.Join(fs.rootPath, "../external"), filepath.Join(fs.rootPath, "/symlink")); err != nil {
+				panic(err)
+			}
 
 			// Delete a file inside the symlinked directory.
-			err = fs.Delete("symlink/source.txt")
+			err := fs.Delete("symlink/source.txt")
 			g.Assert(err).IsNotNil()
-			g.Assert(errors.Is(err, ufs.ErrBadPathResolution)).IsTrue("err is not ErrBadPathResolution")
+			g.Assert(IsPathError(err)).IsTrue()
 
 			// Ensure the file outside the root directory still exists.
-			_, err = os.Lstat(filepath.Join(rfs.root, "foo/source.txt"))
+			_, err = os.Lstat(filepath.Join(fs.rootPath, "../external/source.txt"))
 			g.Assert(err).IsNil()
 		})
 
 		g.It("returns an error when trying to delete a non-existent file symlinked through a directory outside of the root directory", func() {
 			// Create a directory outside the root directory.
-			err := os.Mkdir(filepath.Join(rfs.root, "foo2"), 0o755)
-			g.Assert(err).IsNil()
+			if err := os.Mkdir(filepath.Join(fs.rootPath, "../external"), 0o755); err != nil {
+				panic(err)
+			}
 
 			// Symlink the directory that is outside the root to a file inside the root.
-			err = os.Symlink(filepath.Join(rfs.root, "foo2"), filepath.Join(rfs.root, "server/symlink"))
-			g.Assert(err).IsNil()
+			if err := os.Symlink(filepath.Join(fs.rootPath, "../external"), filepath.Join(fs.rootPath, "/symlink")); err != nil {
+				panic(err)
+			}
 
 			// Delete a file inside the symlinked directory.
-			err = fs.Delete("symlink/source.txt")
+			err := fs.Delete("symlink/source.txt")
 			g.Assert(err).IsNotNil()
-			g.Assert(errors.Is(err, ufs.ErrBadPathResolution)).IsTrue("err is not ErrBadPathResolution")
+			g.Assert(IsPathError(err)).IsTrue()
 		})
 
 		g.AfterEach(func() {
-			_ = fs.TruncateRootDirectory()
+			fs.reset()
+
+			atomic.StoreInt64(&fs.diskUsed, 0)
+			atomic.StoreInt64(&fs.diskLimit, 0)
 		})
 	})
 }

server/filesystem/path.go

@@ -1,43 +1,16 @@
 package filesystem
 
 import (
-	"path/filepath"
-	"strings"
-
 	"emperror.dev/errors"
 )
 
-// Checks if the given file or path is in the server's file denylist. If so, an Error
+// IsIgnored checks if the given file or path is in the server's file denylist. If so, an Error
 // is returned, otherwise nil is returned.
 func (fs *Filesystem) IsIgnored(paths ...string) error {
 	for _, p := range paths {
-		//sp, err := fs.SafePath(p)
-		//if err != nil {
-		//	return err
-		//}
-		// TODO: update logic to use unixFS
 		if fs.denylist.MatchesPath(p) {
-			return errors.WithStack(&Error{code: ErrCodeDenylistFile, path: p, resolved: p})
+			return errors.WithStack(&Error{code: ErrCodeDenylistFile, path: p})
 		}
 	}
 	return nil
 }
-
-// Generate a path to the file by cleaning it up and appending the root server path to it. This
-// DOES NOT guarantee that the file resolves within the server data directory. You'll want to use
-// the fs.unsafeIsInDataDirectory(p) function to confirm.
-func (fs *Filesystem) unsafeFilePath(p string) string {
-	// Calling filepath.Clean on the joined directory will resolve it to the absolute path,
-	// removing any ../ type of resolution arguments, and leaving us with a direct path link.
-	//
-	// This will also trim the existing root path off the beginning of the path passed to
-	// the function since that can get a bit messy.
-	return filepath.Clean(filepath.Join(fs.Path(), strings.TrimPrefix(p, fs.Path())))
-}
-
-// Check that that path string starts with the server data directory path. This function DOES NOT
-// validate that the rest of the path does not end up resolving out of this directory, or that the
-// targeted file or folder is not a symlink doing the same thing.
-func (fs *Filesystem) unsafeIsInDataDirectory(p string) bool {
-	return strings.HasPrefix(strings.TrimSuffix(p, "/")+"/", strings.TrimSuffix(fs.Path(), "/")+"/")
-}

server/filesystem/path_test.go

@@ -8,17 +8,15 @@ import (
 
 	"emperror.dev/errors"
 	. "github.com/franela/goblin"
-
-	"github.com/pterodactyl/wings/internal/ufs"
 )
 
 func TestFilesystem_Path(t *testing.T) {
 	g := Goblin(t)
-	fs, rfs := NewFs()
+	fs := NewFs()
 
 	g.Describe("Path", func() {
 		g.It("returns the root path for the instance", func() {
-			g.Assert(fs.Path()).Equal(filepath.Join(rfs.root, "/server"))
+			g.Assert(fs.Path()).Equal(fs.rootPath)
 		})
 	})
 }
@@ -29,30 +27,24 @@ func TestFilesystem_Path(t *testing.T) {
 // the calls and ensure they all fail with the same reason.
 func TestFilesystem_Blocks_Symlinks(t *testing.T) {
 	g := Goblin(t)
-	fs, rfs := NewFs()
+	fs := NewFs()
 
-	if err := rfs.CreateServerFileFromString("/../malicious.txt", "external content"); err != nil {
+	fs.write("../malicious.txt", []byte("external content"))
+	if err := os.Mkdir(filepath.Join(fs.rootPath, "../malicious_dir"), 0o777); err != nil {
 		panic(err)
 	}
 
-	if err := os.Mkdir(filepath.Join(rfs.root, "/malicious_dir"), 0o777); err != nil {
-		panic(err)
+	links := map[string]string{
+		"../malicious.txt":                "/symlinked.txt",
+		"../malicious_does_not_exist.txt": "/symlinked_does_not_exist.txt",
+		"/symlinked_does_not_exist.txt":   "/symlinked_does_not_exist2.txt",
+		"../malicious_dir":                "/external_dir",
 	}
 
-	if err := os.Symlink(filepath.Join(rfs.root, "malicious.txt"), filepath.Join(rfs.root, "/server/symlinked.txt")); err != nil {
-		panic(err)
-	}
-
-	if err := os.Symlink(filepath.Join(rfs.root, "malicious_does_not_exist.txt"), filepath.Join(rfs.root, "/server/symlinked_does_not_exist.txt")); err != nil {
-		panic(err)
-	}
-
-	if err := os.Symlink(filepath.Join(rfs.root, "/server/symlinked_does_not_exist.txt"), filepath.Join(rfs.root, "/server/symlinked_does_not_exist2.txt")); err != nil {
-		panic(err)
-	}
-
-	if err := os.Symlink(filepath.Join(rfs.root, "/malicious_dir"), filepath.Join(rfs.root, "/server/external_dir")); err != nil {
-		panic(err)
+	for src, dst := range links {
+		if err := os.Symlink(filepath.Join(fs.rootPath, src), filepath.Join(fs.rootPath, dst)); err != nil {
+			panic(err)
+		}
 	}
 
 	g.Describe("Writefile", func() {
@@ -61,7 +53,7 @@ func TestFilesystem_Blocks_Symlinks(t *testing.T) {
 
 			err := fs.Writefile("symlinked.txt", r)
 			g.Assert(err).IsNotNil()
-			g.Assert(errors.Is(err, ufs.ErrBadPathResolution)).IsTrue("err is not ErrBadPathResolution")
+			g.Assert(IsPathError(err)).IsTrue()
 		})
 
 		g.It("cannot write to a non-existent file symlinked outside the root", func() {
@@ -69,7 +61,7 @@ func TestFilesystem_Blocks_Symlinks(t *testing.T) {
 
 			err := fs.Writefile("symlinked_does_not_exist.txt", r)
 			g.Assert(err).IsNotNil()
-			g.Assert(errors.Is(err, ufs.ErrBadPathResolution)).IsTrue("err is not ErrBadPathResolution")
+			g.Assert(IsPathError(err)).IsTrue()
 		})
 
 		g.It("cannot write to chained symlinks with target that does not exist outside the root", func() {
@@ -77,7 +69,7 @@ func TestFilesystem_Blocks_Symlinks(t *testing.T) {
 
 			err := fs.Writefile("symlinked_does_not_exist2.txt", r)
 			g.Assert(err).IsNotNil()
-			g.Assert(errors.Is(err, ufs.ErrBadPathResolution)).IsTrue("err is not ErrBadPathResolution")
+			g.Assert(IsPathError(err)).IsTrue()
 		})
 
 		g.It("cannot write a file to a directory symlinked outside the root", func() {
@@ -85,7 +77,7 @@ func TestFilesystem_Blocks_Symlinks(t *testing.T) {
 
 			err := fs.Writefile("external_dir/foo.txt", r)
 			g.Assert(err).IsNotNil()
-			g.Assert(errors.Is(err, ufs.ErrNotDirectory)).IsTrue("err is not ErrNotDirectory")
+			g.Assert(IsPathError(err)).IsTrue()
 		})
 	})
 
@@ -93,54 +85,75 @@ func TestFilesystem_Blocks_Symlinks(t *testing.T) {
 		g.It("cannot create a directory outside the root", func() {
 			err := fs.CreateDirectory("my_dir", "external_dir")
 			g.Assert(err).IsNotNil()
-			g.Assert(errors.Is(err, ufs.ErrNotDirectory)).IsTrue("err is not ErrNotDirectory")
+			g.Assert(IsPathError(err)).IsTrue()
 		})
 
 		g.It("cannot create a nested directory outside the root", func() {
-			err := fs.CreateDirectory("my/nested/dir", "external_dir/foo/bar")
+			err := fs.CreateDirectory("my/nested/dir", "../external_dir/foo/bar")
 			g.Assert(err).IsNotNil()
-			g.Assert(errors.Is(err, ufs.ErrNotDirectory)).IsTrue("err is not ErrNotDirectory")
+			g.Assert(IsPathError(err)).IsTrue()
 		})
 
 		g.It("cannot create a nested directory outside the root", func() {
-			err := fs.CreateDirectory("my/nested/dir", "external_dir/server")
+			err := fs.CreateDirectory("my/nested/dir", "../external_dir/server")
 			g.Assert(err).IsNotNil()
-			g.Assert(errors.Is(err, ufs.ErrNotDirectory)).IsTrue("err is not ErrNotDirectory")
+			g.Assert(IsPathError(err)).IsTrue()
 		})
 	})
 
 	g.Describe("Rename", func() {
+		// You can rename the symlink file itself, which does not impact the
+		// underlying symlinked target file outside the server directory.
 		g.It("can rename a file symlinked outside the directory root", func() {
-			_, err := os.Lstat(filepath.Join(rfs.root, "server", "symlinked.txt"))
+			err := fs.Rename("symlinked.txt", "foo.txt")
 			g.Assert(err).IsNil()
-			err = fs.Rename("symlinked.txt", "foo.txt")
+
+			st, err := os.Lstat(filepath.Join(fs.rootPath, "foo.txt"))
 			g.Assert(err).IsNil()
-			_, err = os.Lstat(filepath.Join(rfs.root, "server", "foo.txt"))
+			g.Assert(st.Mode()&os.ModeSymlink != 0).IsTrue()
+
+			st, err = os.Lstat(filepath.Join(fs.rootPath, "../malicious.txt"))
 			g.Assert(err).IsNil()
+			g.Assert(st.Mode()&os.ModeSymlink == 0).IsTrue()
 		})
 
-		g.It("can rename a symlinked directory outside the root", func() {
-			_, err := os.Lstat(filepath.Join(rfs.root, "server", "external_dir"))
+		// The same as above, acts on the source directory and not the target directory,
+		// therefore, this is allowed.
+		g.It("can rename a directory symlinked outside the root", func() {
+			err := fs.Rename("external_dir", "foo")
 			g.Assert(err).IsNil()
-			err = fs.Rename("external_dir", "foo")
+
+			st, err := os.Lstat(filepath.Join(fs.rootPath, "foo"))
 			g.Assert(err).IsNil()
-			_, err = os.Lstat(filepath.Join(rfs.root, "server", "foo"))
+			g.Assert(st.IsDir()).IsTrue()
+			g.Assert(st.Mode()&os.ModeSymlink != 0).IsTrue()
+
+			st, err = os.Lstat(filepath.Join(fs.rootPath, "../external_dir"))
 			g.Assert(err).IsNil()
+			g.Assert(st.IsDir()).IsTrue()
+			g.Assert(st.Mode()&os.ModeSymlink == 0).IsTrue()
 		})
 
 		g.It("cannot rename a file to a location outside the directory root", func() {
-			_ = rfs.CreateServerFileFromString("my_file.txt", "internal content")
-			t.Log(rfs.root)
+			fs.write("my_file.txt", []byte("internal content"))
 
-			st, err := os.Lstat(filepath.Join(rfs.root, "server", "foo"))
-			g.Assert(err).IsNil()
-			g.Assert(st.Mode()&ufs.ModeSymlink != 0).IsTrue()
+			err := fs.Rename("my_file.txt", "../external_dir/my_file.txt")
+			g.Assert(err).IsNotNil()
+			g.Assert(IsPathError(err)).IsTrue()
+		})
+	})
 
-			err = fs.Rename("my_file.txt", "foo/my_file.txt")
-			g.Assert(errors.Is(err, ufs.ErrNotDirectory)).IsTrue()
+	g.Describe("Chown", func() {
+		g.It("cannot chown a file symlinked outside the directory root", func() {
+			err := fs.Chown("symlinked.txt")
+			g.Assert(err).IsNotNil()
+			g.Assert(IsPathError(err)).IsTrue()
+		})
 
-			st, err = os.Lstat(filepath.Join(rfs.root, "malicious_dir", "my_file.txt"))
-			g.Assert(errors.Is(err, ufs.ErrNotExist)).IsTrue()
+		g.It("cannot chown a directory symlinked outside the directory root", func() {
+			err := fs.Chown("external_dir")
+			g.Assert(err).IsNotNil()
+			g.Assert(IsPathError(err)).IsTrue()
 		})
 	})
 
@@ -148,7 +161,7 @@ func TestFilesystem_Blocks_Symlinks(t *testing.T) {
 		g.It("cannot copy a file symlinked outside the directory root", func() {
 			err := fs.Copy("symlinked.txt")
 			g.Assert(err).IsNotNil()
-			g.Assert(errors.Is(err, ufs.ErrNotExist)).IsTrue("err is not ErrNotExist")
+			g.Assert(IsPathError(err)).IsTrue()
 		})
 	})
 
@@ -157,14 +170,14 @@ func TestFilesystem_Blocks_Symlinks(t *testing.T) {
 			err := fs.Delete("symlinked.txt")
 			g.Assert(err).IsNil()
 
-			_, err = os.Stat(filepath.Join(rfs.root, "malicious.txt"))
+			_, err = os.Stat(filepath.Join(fs.rootPath, "../malicious.txt"))
 			g.Assert(err).IsNil()
 
-			_, err = rfs.StatServerFile("symlinked.txt")
+			_, err = os.Stat(filepath.Join(fs.rootPath, "symlinked.txt"))
 			g.Assert(err).IsNotNil()
-			g.Assert(errors.Is(err, ufs.ErrNotExist)).IsTrue("err is not ErrNotExist")
+			g.Assert(errors.Is(err, os.ErrNotExist)).IsTrue()
 		})
 	})
 
-	_ = fs.TruncateRootDirectory()
+	fs.reset()
 }

server/filesystem/stat.go

@@ -1,18 +1,17 @@
 package filesystem
 
 import (
-	"encoding/json"
-	"io"
+	"os"
 	"strconv"
 	"time"
 
+	"emperror.dev/errors"
 	"github.com/gabriel-vasile/mimetype"
-
-	"github.com/pterodactyl/wings/internal/ufs"
+	"github.com/goccy/go-json"
 )
 
 type Stat struct {
-	ufs.FileInfo
+	os.FileInfo
 	Mimetype string
 }
 
@@ -33,31 +32,38 @@ func (s *Stat) MarshalJSON() ([]byte, error) {
 		Created:  s.CTime().Format(time.RFC3339),
 		Modified: s.ModTime().Format(time.RFC3339),
 		Mode:     s.Mode().String(),
-		// Using `&ModePerm` on the file's mode will cause the mode to only have the permission values, and nothing else.
-		ModeBits:  strconv.FormatUint(uint64(s.Mode()&ufs.ModePerm), 8),
+		// Using `&os.ModePerm` on the file's mode will cause the mode to only have the permission values, and nothing else.
+		ModeBits:  strconv.FormatUint(uint64(s.Mode()&os.ModePerm), 8),
 		Size:      s.Size(),
 		Directory: s.IsDir(),
 		File:      !s.IsDir(),
-		Symlink:   s.Mode().Type()&ufs.ModeSymlink != 0,
+		Symlink:   s.Mode().Type()&os.ModeSymlink != 0,
 		Mime:      s.Mimetype,
 	})
 }
 
-func statFromFile(f ufs.File) (Stat, error) {
-	s, err := f.Stat()
+// Stat stats a file or folder and returns the base stat object from go along
+// with the MIME data that can be used for editing files.
+func (fs *Filesystem) Stat(p string) (Stat, error) {
+	p = normalize(p)
+	s, err := fs.root.Stat(p)
 	if err != nil {
-		return Stat{}, err
+		return Stat{}, errors.Wrap(err, "server/filesystem: stat: failed to stat file")
 	}
+
 	var m *mimetype.MIME
 	if !s.IsDir() {
+		f, err := fs.root.Open(p)
+		if err != nil {
+			return Stat{}, errors.Wrap(err, "server/filesystem: stat: failed to open file")
+		}
+		defer f.Close()
 		m, err = mimetype.DetectReader(f)
 		if err != nil {
-			return Stat{}, err
-		}
-		if _, err := f.Seek(0, io.SeekStart); err != nil {
-			return Stat{}, err
+			return Stat{}, errors.Wrap(err, "server/filesystem: stat: failed to detect mimetype")
 		}
 	}
+
 	st := Stat{
 		FileInfo: s,
 		Mimetype: "inode/directory",
@@ -65,20 +71,14 @@ func statFromFile(f ufs.File) (Stat, error) {
 	if m != nil {
 		st.Mimetype = m.String()
 	}
+
 	return st, nil
 }
 
-// Stat stats a file or folder and returns the base stat object from go along
-// with the MIME data that can be used for editing files.
-func (fs *Filesystem) Stat(p string) (Stat, error) {
-	f, err := fs.unixFS.Open(p)
+func (fs *Filesystem) Stat2(p string) (os.FileInfo, error) {
+	st, err := fs.root.Stat(normalize(p))
 	if err != nil {
-		return Stat{}, err
-	}
-	defer f.Close()
-	st, err := statFromFile(f)
-	if err != nil {
-		return Stat{}, err
+		return st, errors.Wrap(err, "server/filesystem: stat2: failed to stat file")
 	}
 	return st, nil
 }

server/install.go

@@ -2,6 +2,7 @@ package server
 
 import (
 	"bufio"
+	"bytes"
 	"context"
 	"html/template"
 	"io"
@@ -217,18 +218,30 @@ func (ip *InstallationProcess) tempDir() string {
 // can be properly mounted into the installation container and then executed.
 func (ip *InstallationProcess) writeScriptToDisk() error {
 	// Make sure the temp directory root exists before trying to make a directory within it. The
-	// os.TempDir call expects this base to exist, it won't create it for you.
+	// ioutil.TempDir call expects this base to exist, it won't create it for you.
 	if err := os.MkdirAll(ip.tempDir(), 0o700); err != nil {
 		return errors.WithMessage(err, "could not create temporary directory for install process")
 	}
+
 	f, err := os.OpenFile(filepath.Join(ip.tempDir(), "install.sh"), os.O_RDWR|os.O_CREATE|os.O_TRUNC, 0o644)
 	if err != nil {
 		return errors.WithMessage(err, "failed to write server installation script to disk before mount")
 	}
 	defer f.Close()
-	if _, err := io.Copy(f, strings.NewReader(strings.ReplaceAll(ip.Script.Script, "\r\n", "\n"))); err != nil {
+
+	w := bufio.NewWriter(f)
+
+	scanner := bufio.NewScanner(bytes.NewReader([]byte(ip.Script.Script)))
+	for scanner.Scan() {
+		w.WriteString(scanner.Text() + "\n")
+	}
+
+	if err := scanner.Err(); err != nil {
 		return err
 	}
+
+	w.Flush()
+
 	return nil
 }
 
@@ -443,7 +456,9 @@ func (ip *InstallationProcess) Execute() (string, error) {
 	// to trigger the reinstall of the server. It is possible the directory would
 	// not exist when this runs if Wings boots with a missing directory and a user
 	// triggers a reinstall before trying to start the server.
-	if err := ip.Server.EnsureDataDirectoryExists(); err != nil {
+	// todo: verify, this might be wrong now that the FS requires the directory to
+	//  exist to boot it.
+	if _, err := ip.Server.EnsureDataDirectoryExists(); err != nil {
 		return "", err
 	}
 

server/manager.go

@@ -6,7 +6,6 @@ import (
 	"fmt"
 	"io"
 	"os"
-	"path/filepath"
 	"runtime"
 	"sync"
 	"time"
@@ -196,11 +195,18 @@ func (m *Manager) InitServer(data remote.ServerConfigurationResponse) (*Server,
 		return nil, errors.WithStackIf(err)
 	}
 
-	s.fs, err = filesystem.New(filepath.Join(config.Get().System.Data, s.ID()), s.DiskSpace(), s.Config().Egg.FileDenylist)
+	d, err := s.EnsureDataDirectoryExists()
 	if err != nil {
-		return nil, errors.WithStackIf(err)
+		return nil, err
 	}
 
+	fs, err := filesystem.New(d, s.DiskSpace(), s.Config().Egg.FileDenylist)
+	if err != nil {
+		return nil, err
+	}
+
+	s.fs = fs
+
 	// Right now we only support a Docker based environment, so I'm going to hard code
 	// this logic in. When we're ready to support other environment we'll need to make
 	// some modifications here, obviously.

server/server.go

@@ -257,11 +257,11 @@ func (s *Server) ReadLogfile(len int) ([]string, error) {
 // for the server is setup, and that all of the necessary files are created.
 func (s *Server) CreateEnvironment() error {
 	// Ensure the data directory exists before getting too far through this process.
-	if err := s.EnsureDataDirectoryExists(); err != nil {
+	if _, err := s.EnsureDataDirectoryExists(); err != nil {
 		return err
 	}
 
-	cfg := config.Get()
+	cfg := *config.Get()
 	if cfg.System.MachineID.Enable {
 		// Hytale wants a machine-id in order to encrypt tokens for the server. So
 		// write a machine-id file for the server that contains the server's UUID
@@ -269,7 +269,7 @@ func (s *Server) CreateEnvironment() error {
 		p := filepath.Join(cfg.System.MachineID.Directory, s.ID())
 		machineID := append(bytes.ReplaceAll([]byte(s.ID()), []byte{'-'}, []byte{}), '\n')
 		if err := os.WriteFile(p, machineID, 0o644); err != nil {
-			return fmt.Errorf("failed to write machine-id (at '%s') for server '%s': %w", p, s.ID(), err)
+			return errors.Wrap(err, "server: failed to write machine-id to disk")
 		}
 	}
 
@@ -295,21 +295,25 @@ func (s *Server) Filesystem() *filesystem.Filesystem {
 
 // EnsureDataDirectoryExists ensures that the data directory for the server
 // instance exists.
-func (s *Server) EnsureDataDirectoryExists() error {
-	if _, err := os.Lstat(s.fs.Path()); err != nil {
-		if os.IsNotExist(err) {
-			s.Log().Debug("server: creating root directory and setting permissions")
-			if err := os.MkdirAll(s.fs.Path(), 0o700); err != nil {
-				return errors.WithStack(err)
-			}
-			if err := s.fs.Chown("/"); err != nil {
-				s.Log().WithField("error", err).Warn("server: failed to chown server data directory")
-			}
-		} else {
-			return errors.WrapIf(err, "server: failed to stat server root directory")
+func (s *Server) EnsureDataDirectoryExists() (string, error) {
+	c := *config.Get()
+	path := filepath.Join(c.System.Data, s.ID())
+
+	if _, err := os.Lstat(path); err != nil {
+		if !errors.Is(err, os.ErrNotExist) {
+			return path, errors.Wrap(err, "server: failed to stat server root directory")
+		}
+
+		if err := os.MkdirAll(path, 0o700); err != nil {
+			return path, errors.Wrap(err, "server: failed to create root directory")
+		}
+
+		if err := os.Chown(path, c.System.User.Uid, c.System.User.Gid); err != nil {
+			return path, errors.Wrap(err, "server: failed to chown newly created root directory")
 		}
 	}
-	return nil
+
+	return path, nil
 }
 
 // OnStateChange sets the state of the server internally. This function handles crash detection as

server/transfer/archive.go

@@ -4,14 +4,16 @@ import (
 	"context"
 	"fmt"
 	"io"
+	"os"
 
+	"emperror.dev/errors"
 	"github.com/pterodactyl/wings/internal/progress"
 	"github.com/pterodactyl/wings/server/filesystem"
 )
 
 // Archive returns an archive that can be used to stream the contents of the
 // contents of a server.
-func (t *Transfer) Archive() (*Archive, error) {
+func (t *Transfer) Archive(r *os.Root) (*Archive, error) {
 	if t.archive == nil {
 		// Get the disk usage of the server (used to calculate the progress of the archive process)
 		rawSize, err := t.Server.Filesystem().DiskUsage(true)
@@ -19,8 +21,12 @@ func (t *Transfer) Archive() (*Archive, error) {
 			return nil, fmt.Errorf("transfer: failed to get server disk usage: %w", err)
 		}
 
-		// Create a new archive instance and assign it to the transfer.
-		t.archive = NewArchive(t, uint64(rawSize))
+		a, err := filesystem.NewArchive(r, "/", filesystem.WithProgress(progress.NewProgress(uint64(rawSize))))
+		if err != nil {
+			_ = r.Close()
+			return nil, errors.WrapIf(err, "server/transfer: failed to create archive")
+		}
+		t.archive = &Archive{archive: a}
 	}
 
 	return t.archive, nil
@@ -31,16 +37,6 @@ type Archive struct {
 	archive *filesystem.Archive
 }
 
-// NewArchive returns a new archive associated with the given transfer.
-func NewArchive(t *Transfer, size uint64) *Archive {
-	return &Archive{
-		archive: &filesystem.Archive{
-			Filesystem: t.Server.Filesystem(),
-			Progress:   progress.NewProgress(size),
-		},
-	}
-}
-
 // Stream returns a reader that can be used to stream the contents of the archive.
 func (a *Archive) Stream(ctx context.Context, w io.Writer) error {
 	return a.archive.Stream(ctx, w)
@@ -48,5 +44,5 @@ func (a *Archive) Stream(ctx context.Context, w io.Writer) error {
 
 // Progress returns the current progress of the archive.
 func (a *Archive) Progress() *progress.Progress {
-	return a.archive.Progress
+	return a.archive.Progress()
 }

server/transfer/source.go

@@ -4,13 +4,14 @@ import (
 	"context"
 	"crypto/sha256"
 	"encoding/hex"
-	"errors"
 	"fmt"
 	"io"
 	"mime/multipart"
 	"net/http"
+	"os"
 	"time"
 
+	"emperror.dev/errors"
 	"github.com/pterodactyl/wings/internal/progress"
 )
 
@@ -23,7 +24,13 @@ func (t *Transfer) PushArchiveToTarget(url, token string) ([]byte, error) {
 	t.SendMessage("Preparing to stream server data to destination...")
 	t.SetStatus(StatusProcessing)
 
-	a, err := t.Archive()
+	r, err := os.OpenRoot(t.Server.Filesystem().Path())
+	if err != nil {
+		return nil, errors.Wrap(err, "server/transfer: failed to open root directory")
+	}
+	defer r.Close()
+
+	a, err := t.Archive(r)
 	if err != nil {
 		t.Error(err, "Failed to get archive for transfer.")
 		return nil, errors.New("failed to get archive for transfer")

sftp/handler.go

@@ -121,7 +121,7 @@ func (h *Handler) Filewrite(request *sftp.Request) (io.WriterAt, error) {
 	if !h.can(permission) {
 		return nil, sftp.ErrSSHFxPermissionDenied
 	}
-	f, err := h.fs.Touch(request.Filepath, os.O_RDWR|os.O_TRUNC)
+	f, err := h.fs.Touch(request.Filepath, os.O_RDWR|os.O_CREATE|os.O_TRUNC, 0o644)
 	if err != nil {
 		l.WithField("flags", request.Flags).WithField("error", err).Error("failed to open existing file on system")
 		return nil, sftp.ErrSSHFxFailure
@@ -213,8 +213,6 @@ func (h *Handler) Filecmd(request *sftp.Request) error {
 		}
 		h.events.MustLog(server.ActivitySftpCreateDirectory, FileAction{Entity: request.Filepath})
 		break
-	// Support creating symlinks between files. The source and target must resolve within
-	// the server home directory.
 	case "Symlink":
 		if !h.can(PermissionFileCreate) {
 			return sftp.ErrSSHFxPermissionDenied
@@ -265,14 +263,23 @@ func (h *Handler) Filelist(request *sftp.Request) (sftp.ListerAt, error) {
 
 	switch request.Method {
 	case "List":
-		entries, err := h.fs.ReadDirStat(request.Filepath)
+		d, err := h.fs.ReadDir(request.Filepath)
 		if err != nil {
+			if errors.Is(err, os.ErrNotExist) {
+				return nil, sftp.ErrSSHFxNoSuchFile
+			}
 			h.logger.WithField("source", request.Filepath).WithField("error", err).Error("error while listing directory")
 			return nil, sftp.ErrSSHFxFailure
 		}
-		return ListerAt(entries), nil
+		files := make([]os.FileInfo, len(d))
+		for _, entry := range d {
+			if i, err := entry.Info(); err == nil {
+				files = append(files, i)
+			}
+		}
+		return ListerAt(files), nil
 	case "Stat":
-		st, err := h.fs.Stat(request.Filepath)
+		st, err := h.fs.Stat2(request.Filepath)
 		if err != nil {
 			if errors.Is(err, os.ErrNotExist) {
 				return nil, sftp.ErrSSHFxNoSuchFile
@@ -280,7 +287,7 @@ func (h *Handler) Filelist(request *sftp.Request) (sftp.ListerAt, error) {
 			h.logger.WithField("source", request.Filepath).WithField("error", err).Error("error performing stat on file")
 			return nil, sftp.ErrSSHFxFailure
 		}
-		return ListerAt([]os.FileInfo{st.FileInfo}), nil
+		return ListerAt([]os.FileInfo{st}), nil
 	default:
 		return nil, sftp.ErrSSHFxOpUnsupported
 	}