openpgp/packet: Compact UserAttribute subpacket lengths, fixes signatures.
Necessary to reproduce the same hash for verifying a UserAttribute signature.
Reuse and fix defect in serializeSubpacketLength, RFC 4880, Section 4.2.2.2.
R=agl
CC=golang-dev
https://golang.org/cl/13464044
diff --git a/openpgp/packet/opaque.go b/openpgp/packet/opaque.go
index 7c4d813..5f9ad44 100644
--- a/openpgp/packet/opaque.go
+++ b/openpgp/packet/opaque.go
@@ -7,7 +7,6 @@
import (
"bytes"
"code.google.com/p/go.crypto/openpgp/errors"
- "encoding/binary"
"io"
"io/ioutil"
)
@@ -152,11 +151,9 @@
func (osp *OpaqueSubpacket) Serialize(w io.Writer) (err error) {
buf := make([]byte, 6)
- buf[0] = 0xff
- // Header length includes the subtype byte
- binary.BigEndian.PutUint32(buf[1:5], uint32(len(osp.Contents)+1))
- buf[5] = osp.SubType
- if _, err = w.Write(buf); err != nil {
+ n := serializeSubpacketLength(buf, len(osp.Contents)+1)
+ buf[n] = osp.SubType
+ if _, err = w.Write(buf[:n+1]); err != nil {
return
}
_, err = w.Write(osp.Contents)
diff --git a/openpgp/packet/signature.go b/openpgp/packet/signature.go
index d0d6890..dbed36e 100644
--- a/openpgp/packet/signature.go
+++ b/openpgp/packet/signature.go
@@ -344,13 +344,14 @@
// serializeSubpacketLength marshals the given length into to.
func serializeSubpacketLength(to []byte, length int) int {
+ // RFC 4880, Section 4.2.2.
if length < 192 {
to[0] = byte(length)
return 1
}
if length < 16320 {
length -= 192
- to[0] = byte(length >> 8)
+ to[0] = byte((length >> 8) + 192)
to[1] = byte(length)
return 2
}
