2021-08-22 20:44:14 +00:00

118 lines
3.0 KiB
Go

package configuration
import (
"errors"
"fmt"
"net"
"strings"
"time"
"github.com/qdm12/dns/pkg/blacklist"
"github.com/qdm12/dns/pkg/unbound"
"github.com/qdm12/golibs/params"
)
// DNS contains settings to configure Unbound for DNS over TLS operation.
type DNS struct { //nolint:maligned
Enabled bool
PlaintextAddress net.IP
KeepNameserver bool
UpdatePeriod time.Duration
Unbound unbound.Settings
BlacklistBuild blacklist.BuilderSettings
}
func (settings *DNS) String() string {
return strings.Join(settings.lines(), "\n")
}
func (settings *DNS) lines() (lines []string) {
lines = append(lines, lastIndent+"DNS:")
if settings.PlaintextAddress != nil {
lines = append(lines, indent+lastIndent+"Plaintext address: "+settings.PlaintextAddress.String())
}
if settings.KeepNameserver {
lines = append(lines, indent+lastIndent+"Keep nameserver (disabled blocking): yes")
}
if !settings.Enabled {
return lines
}
lines = append(lines, indent+lastIndent+"DNS over TLS:")
lines = append(lines, indent+indent+lastIndent+"Unbound:")
for _, line := range settings.Unbound.Lines() {
lines = append(lines, indent+indent+indent+line)
}
lines = append(lines, indent+indent+lastIndent+"Blacklist:")
for _, line := range settings.BlacklistBuild.Lines(indent, lastIndent) {
lines = append(lines, indent+indent+indent+line)
}
if settings.UpdatePeriod > 0 {
lines = append(lines, indent+indent+lastIndent+"Update: every "+settings.UpdatePeriod.String())
}
return lines
}
var (
ErrUnboundSettings = errors.New("failed getting Unbound settings")
ErrBlacklistSettings = errors.New("failed getting DNS blacklist settings")
)
func (settings *DNS) read(r reader) (err error) {
settings.Enabled, err = r.env.OnOff("DOT", params.Default("on"))
if err != nil {
return fmt.Errorf("environment variable DOT: %w", err)
}
// Plain DNS settings
if err := settings.readDNSPlaintext(r.env); err != nil {
return err
}
settings.KeepNameserver, err = r.env.OnOff("DNS_KEEP_NAMESERVER", params.Default("off"))
if err != nil {
return fmt.Errorf("environment variable DNS_KEEP_NAMESERVER: %w", err)
}
// DNS over TLS external settings
if err := settings.readBlacklistBuilding(r); err != nil {
return fmt.Errorf("%w: %s", ErrBlacklistSettings, err)
}
settings.UpdatePeriod, err = r.env.Duration("DNS_UPDATE_PERIOD", params.Default("24h"))
if err != nil {
return fmt.Errorf("environment variable DNS_UPDATE_PERIOD: %w", err)
}
// Unbound settings
if err := settings.readUnbound(r); err != nil {
return fmt.Errorf("%w: %s", ErrUnboundSettings, err)
}
return nil
}
var (
ErrDNSAddressNotAnIP = errors.New("DNS plaintext address is not an IP address")
)
func (settings *DNS) readDNSPlaintext(env params.Interface) error {
s, err := env.Get("DNS_PLAINTEXT_ADDRESS", params.Default("1.1.1.1"))
if err != nil {
return fmt.Errorf("environment variable DNS_PLAINTEXT_ADDRESS: %w", err)
}
settings.PlaintextAddress = net.ParseIP(s)
if settings.PlaintextAddress == nil {
return fmt.Errorf("%w: %s", ErrDNSAddressNotAnIP, s)
}
return nil
}