fortify/internal/app/share.pulse.go

117 lines
3.2 KiB
Go

package app
import (
"errors"
"fmt"
"io/fs"
"os"
"path"
"git.ophivana.moe/cat/fortify/acl"
"git.ophivana.moe/cat/fortify/internal/state"
)
const (
pulseServer = "PULSE_SERVER"
pulseCookie = "PULSE_COOKIE"
home = "HOME"
xdgConfigHome = "XDG_CONFIG_HOME"
)
var (
ErrPulseCookie = errors.New("pulse cookie not present")
ErrPulseSocket = errors.New("pulse socket not present")
ErrPulseMode = errors.New("unexpected pulse socket mode")
)
type (
PulseCookieAccessError BaseError
PulseSocketAccessError BaseError
)
func (seal *appSeal) sharePulse() error {
if !seal.et.Has(state.EnablePulse) {
return nil
}
// ensure PulseAudio directory ACL (e.g. `/run/user/%d/pulse`)
pd := path.Join(seal.RuntimePath, "pulse")
ps := path.Join(pd, "native")
if _, err := os.Stat(pd); err != nil {
if !errors.Is(err, fs.ErrNotExist) {
return (*PulseSocketAccessError)(wrapError(err,
fmt.Sprintf("cannot access PulseAudio directory '%s':", pd), err))
}
return (*PulseSocketAccessError)(wrapError(ErrPulseSocket,
fmt.Sprintf("PulseAudio directory '%s' not found", pd)))
}
seal.appendEnv(pulseServer, "unix:"+ps)
seal.sys.updatePerm(pd, acl.Execute)
// ensure PulseAudio socket permission (e.g. `/run/user/%d/pulse/native`)
if s, err := os.Stat(ps); err != nil {
if !errors.Is(err, fs.ErrNotExist) {
return (*PulseSocketAccessError)(wrapError(err,
fmt.Sprintf("cannot access PulseAudio socket '%s':", ps), err))
}
return (*PulseSocketAccessError)(wrapError(ErrPulseSocket,
fmt.Sprintf("PulseAudio directory '%s' found but socket does not exist", pd)))
} else {
if m := s.Mode(); m&0o006 != 0o006 {
return (*PulseSocketAccessError)(wrapError(ErrPulseMode,
fmt.Sprintf("unexpected permissions on '%s':", ps), m))
}
}
// publish current user's pulse cookie for target user
if src, err := discoverPulseCookie(); err != nil {
return err
} else {
dst := path.Join(seal.share, "pulse-cookie")
seal.appendEnv(pulseCookie, dst)
seal.sys.copyFile(dst, src)
}
return nil
}
// discoverPulseCookie attempts various standard methods to discover the current user's PulseAudio authentication cookie
func discoverPulseCookie() (string, error) {
if p, ok := os.LookupEnv(pulseCookie); ok {
return p, nil
}
// dotfile $HOME/.pulse-cookie
if p, ok := os.LookupEnv(home); ok {
p = path.Join(p, ".pulse-cookie")
if s, err := os.Stat(p); err != nil {
if !errors.Is(err, fs.ErrNotExist) {
return p, (*PulseCookieAccessError)(wrapError(err,
fmt.Sprintf("cannot access PulseAudio cookie '%s':", p), err))
}
// not found, try next method
} else if !s.IsDir() {
return p, nil
}
}
// $XDG_CONFIG_HOME/pulse/cookie
if p, ok := os.LookupEnv(xdgConfigHome); ok {
p = path.Join(p, "pulse", "cookie")
if s, err := os.Stat(p); err != nil {
if !errors.Is(err, fs.ErrNotExist) {
return p, (*PulseCookieAccessError)(wrapError(err, "cannot access PulseAudio cookie", p+":", err))
}
// not found, try next method
} else if !s.IsDir() {
return p, nil
}
}
return "", (*PulseCookieAccessError)(wrapError(ErrPulseCookie,
fmt.Sprintf("cannot locate PulseAudio cookie (tried $%s, $%s/pulse/cookie, $%s/.pulse-cookie)",
pulseCookie, xdgConfigHome, home)))
}