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package internal
import (
"errors"
"fmt"
"io/fs"
"os"
"os/user"
"git.ophivana.moe/cat/fortify/acl"
"git.ophivana.moe/cat/fortify/dbus"
"git.ophivana.moe/cat/fortify/internal/verbose"
"git.ophivana.moe/cat/fortify/xcb"
)
// ExitState keeps track of various changes fortify made to the system
// as well as other resources that need to be manually released.
// NOT thread safe.
type ExitState struct {
// target fortified user inherited from app.App
user *user.User
// integer UID of targeted user
uid int
// returns amount of launcher states read
launcherStateCount func() (int, error)
// paths to strip ACLs (of target user) from
aclCleanupCandidate []string
// target process capability enablements
enablements *Enablements
// whether the xcb.ChangeHosts action was complete
xcbActionComplete bool
// reference to D-Bus proxy instance, nil if disabled
dbusProxy *dbus.Proxy
// D-Bus wait complete notification
dbusDone *chan struct{}
// path to fortify process state information
statePath string
// prevents cleanup from happening twice
complete bool
}
// RegisterRevertPath registers a path with ACLs added by fortify
func (s *ExitState) RegisterRevertPath(p string) {
s.aclCleanupCandidate = append(s.aclCleanupCandidate, p)
}
// SealEnablements submits the child process enablements
func (s *ExitState) SealEnablements(e Enablements) {
if s.enablements != nil {
panic("enablement exit state set twice")
}
s.enablements = &e
}
// XcbActionComplete submits xcb.ChangeHosts action completion
func (s *ExitState) XcbActionComplete() {
if s.xcbActionComplete {
Fatal("xcb inserted twice")
}
s.xcbActionComplete = true
}
// SealDBus submits the child's D-Bus proxy instance
func (s *ExitState) SealDBus(p *dbus.Proxy, done *chan struct{}) {
if p == nil {
Fatal("unexpected nil dbus proxy exit state submitted")
}
if s.dbusProxy != nil {
Fatal("dbus proxy exit state set twice")
}
s.dbusProxy = p
s.dbusDone = done
}
// SealStatePath submits filesystem path to the fortify process's state file
func (s *ExitState) SealStatePath(v string) {
if s.statePath != "" {
panic("statePath set twice")
}
s.statePath = v
}
// NewExit initialises a new ExitState containing basic, unchanging information
// about the fortify process required during cleanup
func NewExit(u *user.User, uid int, f func() (int, error)) *ExitState {
return &ExitState{
uid: uid,
user: u,
launcherStateCount: f,
}
}
func Fatal(msg ...any) {
fmt.Println(msg...)
BeforeExit()
os.Exit(1)
}
var exitState *ExitState
func SealExit(s *ExitState) {
if exitState != nil {
panic("exit state submitted twice")
}
exitState = s
}
func BeforeExit() {
if exitState == nil {
fmt.Println("warn: cleanup attempted before exit state submission")
return
}
exitState.beforeExit()
}
func (s *ExitState) beforeExit() {
if s.complete {
panic("beforeExit called twice")
}
if s.statePath == "" {
verbose.Println("State path is unset")
} else {
if err := os.Remove(s.statePath); err != nil && !errors.Is(err, fs.ErrNotExist) {
fmt.Println("Error removing state file:", err)
}
}
if count, err := s.launcherStateCount(); err != nil {
fmt.Println("Error reading active launchers:", err)
os.Exit(1)
} else if count > 0 {
// other launchers are still active
verbose.Printf("Found %d active launchers, exiting without cleaning up\n", count)
return
}
verbose.Println("No other launchers active, will clean up")
if s.xcbActionComplete {
verbose.Printf("X11: Removing XHost entry SI:localuser:%s\n", s.user.Username)
if err := xcb.ChangeHosts(xcb.HostModeDelete, xcb.FamilyServerInterpreted, "localuser\x00"+s.user.Username); err != nil {
fmt.Println("Error removing XHost entry:", err)
}
}
for _, candidate := range s.aclCleanupCandidate {
if err := acl.UpdatePerm(candidate, s.uid); err != nil {
fmt.Printf("Error stripping ACL entry from '%s': %s\n", candidate, err)
}
verbose.Printf("Stripped ACL entry for user '%s' from '%s'\n", s.user.Username, candidate)
}
if s.dbusProxy != nil {
verbose.Println("D-Bus proxy registered, cleaning up")
if err := s.dbusProxy.Close(); err != nil {
if errors.Is(err, os.ErrClosed) {
verbose.Println("D-Bus proxy already closed")
} else {
fmt.Println("Error closing D-Bus proxy:", err)
}
}
// wait for Proxy.Wait to return
<-*s.dbusDone
}
}
|
