// decryptEntity calls gnupg-agent and pinentry to obtain a passphrase and
// decrypt the private key of a given entity (thank you, camlistore folks)
func decryptEntity(s *openpgp.Entity) (ds *openpgp.Entity, err error) {
defer func() {
if e := recover(); e != nil {
err = fmt.Errorf("decryptEntity(): %v", e)
}
}()
ds = s
// TODO: syscall.Mlock a region and keep pass phrase in it.
pubk := &ds.PrivateKey.PublicKey
desc := fmt.Sprintf("Need to unlock GPG key %s to use it for signing.",
pubk.KeyIdShortString())
conn, err := gpgagent.NewConn()
switch err {
case gpgagent.ErrNoAgent:
fmt.Fprintf(os.Stderr, "Note: gpg-agent not found; resorting to on-demand password entry.\n")
case nil:
defer conn.Close()
req := &gpgagent.PassphraseRequest{
CacheKey: "go:pgpencrypt:" + pubk.KeyIdShortString(),
Prompt: "Passphrase",
Desc: desc,
}
for tries := 0; tries < 3; tries++ {
pass, err := conn.GetPassphrase(req)
if err == nil {
err = ds.PrivateKey.Decrypt([]byte(pass))
if err == nil {
return ds, err
}
req.Error = "Passphrase failed to decrypt: " + err.Error()
conn.RemoveFromCache(req.CacheKey)
continue
}
if err == gpgagent.ErrCancel {
panic("failed to decrypt key; action canceled")
}
}
default:
panic(err)
}
pinReq := &pinentry.Request{Desc: desc, Prompt: "Passphrase"}
for tries := 0; tries < 3; tries++ {
pass, err := pinReq.GetPIN()
if err == nil {
err = ds.PrivateKey.Decrypt([]byte(pass))
if err == nil {
return ds, err
}
pinReq.Error = "Passphrase failed to decrypt: " + err.Error()
continue
}
if err == pinentry.ErrCancel {
panic("failed to decrypt key; action canceled")
}
}
return ds, fmt.Errorf("decryptEntity(): failed to decrypt key %q: %v", pubk.KeyIdShortString(), err)
}
func (fe *FileEntityFetcher) decryptEntity(e *openpgp.Entity) error {
// TODO: syscall.Mlock a region and keep pass phrase in it.
pubk := &e.PrivateKey.PublicKey
desc := fmt.Sprintf("Need to unlock GPG key %s to use it for signing.",
pubk.KeyIdShortString())
conn, err := gpgagent.NewConn()
switch err {
case gpgagent.ErrNoAgent:
fmt.Fprintf(os.Stderr, "Note: gpg-agent not found; resorting to on-demand password entry.\n")
case nil:
defer conn.Close()
req := &gpgagent.PassphraseRequest{
CacheKey: "camli:jsonsign:" + pubk.KeyIdShortString(),
Prompt: "Passphrase",
Desc: desc,
}
for tries := 0; tries < 2; tries++ {
pass, err := conn.GetPassphrase(req)
if err == nil {
err = e.PrivateKey.Decrypt([]byte(pass))
if err == nil {
return nil
}
req.Error = "Passphrase failed to decrypt: " + err.Error()
conn.RemoveFromCache(req.CacheKey)
continue
}
if err == gpgagent.ErrCancel {
return errors.New("jsonsign: failed to decrypt key; action canceled")
}
log.Printf("jsonsign: gpgagent: %v", err)
}
default:
log.Printf("jsonsign: gpgagent: %v", err)
}
pinReq := &pinentry.Request{Desc: desc, Prompt: "Passphrase"}
for tries := 0; tries < 2; tries++ {
pass, err := pinReq.GetPIN()
if err == nil {
err = e.PrivateKey.Decrypt([]byte(pass))
if err == nil {
return nil
}
pinReq.Error = "Passphrase failed to decrypt: " + err.Error()
continue
}
if err == pinentry.ErrCancel {
return errors.New("jsonsign: failed to decrypt key; action canceled")
}
log.Printf("jsonsign: pinentry: %v", err)
}
return fmt.Errorf("jsonsign: failed to decrypt key %q", pubk.KeyIdShortString())
}