diff options
Diffstat (limited to 'internal/app/shim/proc.go')
| -rw-r--r-- | internal/app/shim/proc.go | 117 |
1 files changed, 0 insertions, 117 deletions
diff --git a/internal/app/shim/proc.go b/internal/app/shim/proc.go deleted file mode 100644 index 8c73e697..00000000 --- a/internal/app/shim/proc.go +++ /dev/null @@ -1,117 +0,0 @@ -package shim - -import ( - "context" - "encoding/gob" - "errors" - "os" - "os/exec" - "strconv" - "strings" - "syscall" - "time" - - "git.gensokyo.uk/security/fortify/internal" - "git.gensokyo.uk/security/fortify/internal/fmsg" - "git.gensokyo.uk/security/fortify/sandbox" -) - -// used by the parent process - -type Shim struct { - // user switcher process - cmd *exec.Cmd - // fallback exit notifier with error returned killing the process - killFallback chan error - // monitor to shim encoder - encoder *gob.Encoder -} - -func (s *Shim) Unwrap() *exec.Cmd { return s.cmd } -func (s *Shim) Fallback() chan error { return s.killFallback } - -func (s *Shim) String() string { - if s.cmd == nil { - return "(unused shim manager)" - } - return s.cmd.String() -} - -func (s *Shim) Start( - aid string, - supp []string, -) (*time.Time, error) { - // prepare user switcher invocation - fsuPath := internal.MustFsuPath() - s.cmd = exec.Command(fsuPath) - - // pass shim setup pipe - if fd, e, err := sandbox.Setup(&s.cmd.ExtraFiles); err != nil { - return nil, fmsg.WrapErrorSuffix(err, - "cannot create shim setup pipe:") - } else { - s.encoder = e - s.cmd.Env = []string{ - Env + "=" + strconv.Itoa(fd), - "FORTIFY_APP_ID=" + aid, - } - } - - // format fsu supplementary groups - if len(supp) > 0 { - fmsg.Verbosef("attaching supplementary group ids %s", supp) - s.cmd.Env = append(s.cmd.Env, "FORTIFY_GROUPS="+strings.Join(supp, " ")) - } - s.cmd.Stdin, s.cmd.Stdout, s.cmd.Stderr = os.Stdin, os.Stdout, os.Stderr - s.cmd.Dir = "/" - - fmsg.Verbose("starting shim via fsu:", s.cmd) - // withhold messages to stderr - fmsg.Suspend() - if err := s.cmd.Start(); err != nil { - return nil, fmsg.WrapErrorSuffix(err, - "cannot start fsu:") - } - startTime := time.Now().UTC() - - return &startTime, nil -} - -func (s *Shim) Serve(ctx context.Context, params *Params) error { - // kill shim if something goes wrong and an error is returned - s.killFallback = make(chan error, 1) - killShim := func() { - if err := s.cmd.Process.Signal(os.Interrupt); err != nil { - s.killFallback <- err - } - } - defer func() { killShim() }() - - encodeErr := make(chan error) - go func() { encodeErr <- s.encoder.Encode(params) }() - - select { - // encode return indicates setup completion - case err := <-encodeErr: - if err != nil { - return fmsg.WrapErrorSuffix(err, - "cannot transmit shim config:") - } - killShim = func() {} - return nil - - // setup canceled before payload was accepted - case <-ctx.Done(): - err := ctx.Err() - if errors.Is(err, context.Canceled) { - return fmsg.WrapError(syscall.ECANCELED, - "shim setup canceled") - } - if errors.Is(err, context.DeadlineExceeded) { - return fmsg.WrapError(syscall.ETIMEDOUT, - "deadline exceeded waiting for shim") - } - // unreachable - return err - } -} |
