func (ops *OnePassSignature) parse(r io.Reader) (err error) {
var buf [13]byte
_, err = readFull(r, buf[:])
if err != nil {
return
}
if buf[0] != onePassSignatureVersion {
err = errors.UnsupportedError("one-pass-signature packet version " + strconv.Itoa(int(buf[0])))
}
var ok bool
ops.Hash, ok = s2k.HashIdToHash(buf[2])
if !ok {
return errors.UnsupportedError("hash function: " + strconv.Itoa(int(buf[2])))
}
ops.SigType = SignatureType(buf[1])
ops.PubKeyAlgo = PublicKeyAlgorithm(buf[3])
ops.KeyId = binary.BigEndian.Uint64(buf[4:12])
ops.IsLast = buf[12] != 0
return
}
func (sig *Signature) parse(r io.Reader) (err error) {
// RFC 4880, section 5.2.3
var buf [5]byte
_, err = readFull(r, buf[:1])
if err != nil {
return
}
if buf[0] != 4 {
err = errors.UnsupportedError("signature packet version " + strconv.Itoa(int(buf[0])))
return
}
_, err = readFull(r, buf[:5])
if err != nil {
return
}
sig.SigType = SignatureType(buf[0])
sig.PubKeyAlgo = PublicKeyAlgorithm(buf[1])
switch sig.PubKeyAlgo {
case PubKeyAlgoRSA, PubKeyAlgoRSASignOnly, PubKeyAlgoDSA, PubKeyAlgoECDSA:
default:
err = errors.UnsupportedError("public key algorithm " + strconv.Itoa(int(sig.PubKeyAlgo)))
return
}
var ok bool
sig.Hash, ok = s2k.HashIdToHash(buf[2])
if !ok {
return errors.UnsupportedError("hash function " + strconv.Itoa(int(buf[2])))
}
hashedSubpacketsLength := int(buf[3])<<8 | int(buf[4])
l := 6 + hashedSubpacketsLength
sig.HashSuffix = make([]byte, l+6)
sig.HashSuffix[0] = 4
copy(sig.HashSuffix[1:], buf[:5])
hashedSubpackets := sig.HashSuffix[6:l]
_, err = readFull(r, hashedSubpackets)
if err != nil {
return
}
// See RFC 4880, section 5.2.4
trailer := sig.HashSuffix[l:]
trailer[0] = 4
trailer[1] = 0xff
trailer[2] = uint8(l >> 24)
trailer[3] = uint8(l >> 16)
trailer[4] = uint8(l >> 8)
trailer[5] = uint8(l)
err = parseSignatureSubpackets(sig, hashedSubpackets, true)
if err != nil {
return
}
_, err = readFull(r, buf[:2])
if err != nil {
return
}
unhashedSubpacketsLength := int(buf[0])<<8 | int(buf[1])
unhashedSubpackets := make([]byte, unhashedSubpacketsLength)
_, err = readFull(r, unhashedSubpackets)
if err != nil {
return
}
err = parseSignatureSubpackets(sig, unhashedSubpackets, false)
if err != nil {
return
}
_, err = readFull(r, sig.HashTag[:2])
if err != nil {
return
}
switch sig.PubKeyAlgo {
case PubKeyAlgoRSA, PubKeyAlgoRSASignOnly:
sig.RSASignature.bytes, sig.RSASignature.bitLength, err = readMPI(r)
case PubKeyAlgoDSA:
sig.DSASigR.bytes, sig.DSASigR.bitLength, err = readMPI(r)
if err == nil {
sig.DSASigS.bytes, sig.DSASigS.bitLength, err = readMPI(r)
}
case PubKeyAlgoECDSA:
sig.ECDSASigR.bytes, sig.ECDSASigR.bitLength, err = readMPI(r)
if err == nil {
sig.ECDSASigS.bytes, sig.ECDSASigS.bitLength, err = readMPI(r)
}
default:
panic("unreachable")
}
return
}
func (sig *SignatureV3) parse(r io.Reader) (err error) {
// RFC 4880, section 5.2.2
var buf [8]byte
if _, err = readFull(r, buf[:1]); err != nil {
return
}
if buf[0] < 2 || buf[0] > 3 {
err = errors.UnsupportedError("signature packet version " + strconv.Itoa(int(buf[0])))
return
}
if _, err = readFull(r, buf[:1]); err != nil {
return
}
if buf[0] != 5 {
err = errors.UnsupportedError(
"invalid hashed material length " + strconv.Itoa(int(buf[0])))
return
}
// Read hashed material: signature type + creation time
if _, err = readFull(r, buf[:5]); err != nil {
return
}
sig.SigType = SignatureType(buf[0])
t := binary.BigEndian.Uint32(buf[1:5])
sig.CreationTime = time.Unix(int64(t), 0)
// Eight-octet Key ID of signer.
if _, err = readFull(r, buf[:8]); err != nil {
return
}
sig.IssuerKeyId = binary.BigEndian.Uint64(buf[:])
// Public-key and hash algorithm
if _, err = readFull(r, buf[:2]); err != nil {
return
}
sig.PubKeyAlgo = PublicKeyAlgorithm(buf[0])
switch sig.PubKeyAlgo {
case PubKeyAlgoRSA, PubKeyAlgoRSASignOnly, PubKeyAlgoDSA:
default:
err = errors.UnsupportedError("public key algorithm " + strconv.Itoa(int(sig.PubKeyAlgo)))
return
}
var ok bool
if sig.Hash, ok = s2k.HashIdToHash(buf[1]); !ok {
return errors.UnsupportedError("hash function " + strconv.Itoa(int(buf[2])))
}
// Two-octet field holding left 16 bits of signed hash value.
if _, err = readFull(r, sig.HashTag[:2]); err != nil {
return
}
switch sig.PubKeyAlgo {
case PubKeyAlgoRSA, PubKeyAlgoRSASignOnly:
sig.RSASignature.bytes, sig.RSASignature.bitLength, err = readMPI(r)
case PubKeyAlgoDSA:
if sig.DSASigR.bytes, sig.DSASigR.bitLength, err = readMPI(r); err != nil {
return
}
sig.DSASigS.bytes, sig.DSASigS.bitLength, err = readMPI(r)
default:
panic("unreachable")
}
return
}
