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authorOndřej Surý <ondrej@sury.org>2011-09-13 13:13:40 +0200
committerOndřej Surý <ondrej@sury.org>2011-09-13 13:13:40 +0200
commit5ff4c17907d5b19510a62e08fd8d3b11e62b431d (patch)
treec0650497e988f47be9c6f2324fa692a52dea82e1 /src/pkg/crypto/openpgp/packet
parent80f18fc933cf3f3e829c5455a1023d69f7b86e52 (diff)
downloadgolang-upstream/60.tar.gz
Imported Upstream version 60upstream/60
Diffstat (limited to 'src/pkg/crypto/openpgp/packet')
-rw-r--r--src/pkg/crypto/openpgp/packet/Makefile22
-rw-r--r--src/pkg/crypto/openpgp/packet/compressed.go39
-rw-r--r--src/pkg/crypto/openpgp/packet/compressed_test.go41
-rw-r--r--src/pkg/crypto/openpgp/packet/encrypted_key.go168
-rw-r--r--src/pkg/crypto/openpgp/packet/encrypted_key_test.go126
-rw-r--r--src/pkg/crypto/openpgp/packet/literal.go90
-rw-r--r--src/pkg/crypto/openpgp/packet/one_pass_signature.go74
-rw-r--r--src/pkg/crypto/openpgp/packet/packet.go483
-rw-r--r--src/pkg/crypto/openpgp/packet/packet_test.go256
-rw-r--r--src/pkg/crypto/openpgp/packet/private_key.go301
-rw-r--r--src/pkg/crypto/openpgp/packet/private_key_test.go57
-rw-r--r--src/pkg/crypto/openpgp/packet/public_key.go393
-rw-r--r--src/pkg/crypto/openpgp/packet/public_key_test.go98
-rw-r--r--src/pkg/crypto/openpgp/packet/reader.go63
-rw-r--r--src/pkg/crypto/openpgp/packet/signature.go558
-rw-r--r--src/pkg/crypto/openpgp/packet/signature_test.go42
-rw-r--r--src/pkg/crypto/openpgp/packet/symmetric_key_encrypted.go162
-rw-r--r--src/pkg/crypto/openpgp/packet/symmetric_key_encrypted_test.go101
-rw-r--r--src/pkg/crypto/openpgp/packet/symmetrically_encrypted.go291
-rw-r--r--src/pkg/crypto/openpgp/packet/symmetrically_encrypted_test.go124
-rw-r--r--src/pkg/crypto/openpgp/packet/userid.go161
-rw-r--r--src/pkg/crypto/openpgp/packet/userid_test.go87
22 files changed, 3737 insertions, 0 deletions
diff --git a/src/pkg/crypto/openpgp/packet/Makefile b/src/pkg/crypto/openpgp/packet/Makefile
new file mode 100644
index 000000000..0f0d94eb1
--- /dev/null
+++ b/src/pkg/crypto/openpgp/packet/Makefile
@@ -0,0 +1,22 @@
+# Copyright 2011 The Go Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style
+# license that can be found in the LICENSE file.
+
+include ../../../../Make.inc
+
+TARG=crypto/openpgp/packet
+GOFILES=\
+ compressed.go\
+ encrypted_key.go\
+ literal.go\
+ one_pass_signature.go\
+ packet.go\
+ private_key.go\
+ public_key.go\
+ reader.go\
+ signature.go\
+ symmetrically_encrypted.go\
+ symmetric_key_encrypted.go\
+ userid.go\
+
+include ../../../../Make.pkg
diff --git a/src/pkg/crypto/openpgp/packet/compressed.go b/src/pkg/crypto/openpgp/packet/compressed.go
new file mode 100644
index 000000000..1c15c24c4
--- /dev/null
+++ b/src/pkg/crypto/openpgp/packet/compressed.go
@@ -0,0 +1,39 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package packet
+
+import (
+ "compress/flate"
+ "compress/zlib"
+ "crypto/openpgp/error"
+ "io"
+ "os"
+ "strconv"
+)
+
+// Compressed represents a compressed OpenPGP packet. The decompressed contents
+// will contain more OpenPGP packets. See RFC 4880, section 5.6.
+type Compressed struct {
+ Body io.Reader
+}
+
+func (c *Compressed) parse(r io.Reader) os.Error {
+ var buf [1]byte
+ _, err := readFull(r, buf[:])
+ if err != nil {
+ return err
+ }
+
+ switch buf[0] {
+ case 1:
+ c.Body = flate.NewReader(r)
+ case 2:
+ c.Body, err = zlib.NewReader(r)
+ default:
+ err = error.UnsupportedError("unknown compression algorithm: " + strconv.Itoa(int(buf[0])))
+ }
+
+ return err
+}
diff --git a/src/pkg/crypto/openpgp/packet/compressed_test.go b/src/pkg/crypto/openpgp/packet/compressed_test.go
new file mode 100644
index 000000000..24fe501ed
--- /dev/null
+++ b/src/pkg/crypto/openpgp/packet/compressed_test.go
@@ -0,0 +1,41 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package packet
+
+import (
+ "bytes"
+ "encoding/hex"
+ "os"
+ "io/ioutil"
+ "testing"
+)
+
+func TestCompressed(t *testing.T) {
+ packet, err := Read(readerFromHex(compressedHex))
+ if err != nil {
+ t.Errorf("failed to read Compressed: %s", err)
+ return
+ }
+
+ c, ok := packet.(*Compressed)
+ if !ok {
+ t.Error("didn't find Compressed packet")
+ return
+ }
+
+ contents, err := ioutil.ReadAll(c.Body)
+ if err != nil && err != os.EOF {
+ t.Error(err)
+ return
+ }
+
+ expected, _ := hex.DecodeString(compressedExpectedHex)
+ if !bytes.Equal(expected, contents) {
+ t.Errorf("got:%x want:%x", contents, expected)
+ }
+}
+
+const compressedHex = "a3013b2d90c4e02b72e25f727e5e496a5e49b11e1700"
+const compressedExpectedHex = "cb1062004d14c8fe636f6e74656e74732e0a"
diff --git a/src/pkg/crypto/openpgp/packet/encrypted_key.go b/src/pkg/crypto/openpgp/packet/encrypted_key.go
new file mode 100644
index 000000000..b4730cbc9
--- /dev/null
+++ b/src/pkg/crypto/openpgp/packet/encrypted_key.go
@@ -0,0 +1,168 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package packet
+
+import (
+ "big"
+ "crypto/openpgp/elgamal"
+ "crypto/openpgp/error"
+ "crypto/rand"
+ "crypto/rsa"
+ "encoding/binary"
+ "io"
+ "os"
+ "strconv"
+)
+
+const encryptedKeyVersion = 3
+
+// EncryptedKey represents a public-key encrypted session key. See RFC 4880,
+// section 5.1.
+type EncryptedKey struct {
+ KeyId uint64
+ Algo PublicKeyAlgorithm
+ CipherFunc CipherFunction // only valid after a successful Decrypt
+ Key []byte // only valid after a successful Decrypt
+
+ encryptedMPI1, encryptedMPI2 []byte
+}
+
+func (e *EncryptedKey) parse(r io.Reader) (err os.Error) {
+ var buf [10]byte
+ _, err = readFull(r, buf[:])
+ if err != nil {
+ return
+ }
+ if buf[0] != encryptedKeyVersion {
+ return error.UnsupportedError("unknown EncryptedKey version " + strconv.Itoa(int(buf[0])))
+ }
+ e.KeyId = binary.BigEndian.Uint64(buf[1:9])
+ e.Algo = PublicKeyAlgorithm(buf[9])
+ switch e.Algo {
+ case PubKeyAlgoRSA, PubKeyAlgoRSAEncryptOnly:
+ e.encryptedMPI1, _, err = readMPI(r)
+ case PubKeyAlgoElGamal:
+ e.encryptedMPI1, _, err = readMPI(r)
+ if err != nil {
+ return
+ }
+ e.encryptedMPI2, _, err = readMPI(r)
+ }
+ _, err = consumeAll(r)
+ return
+}
+
+func checksumKeyMaterial(key []byte) uint16 {
+ var checksum uint16
+ for _, v := range key {
+ checksum += uint16(v)
+ }
+ return checksum
+}
+
+// Decrypt decrypts an encrypted session key with the given private key. The
+// private key must have been decrypted first.
+func (e *EncryptedKey) Decrypt(priv *PrivateKey) os.Error {
+ var err os.Error
+ var b []byte
+
+ // TODO(agl): use session key decryption routines here to avoid
+ // padding oracle attacks.
+ switch priv.PubKeyAlgo {
+ case PubKeyAlgoRSA, PubKeyAlgoRSAEncryptOnly:
+ b, err = rsa.DecryptPKCS1v15(rand.Reader, priv.PrivateKey.(*rsa.PrivateKey), e.encryptedMPI1)
+ case PubKeyAlgoElGamal:
+ c1 := new(big.Int).SetBytes(e.encryptedMPI1)
+ c2 := new(big.Int).SetBytes(e.encryptedMPI2)
+ b, err = elgamal.Decrypt(priv.PrivateKey.(*elgamal.PrivateKey), c1, c2)
+ default:
+ err = error.InvalidArgumentError("cannot decrypted encrypted session key with private key of type " + strconv.Itoa(int(priv.PubKeyAlgo)))
+ }
+
+ if err != nil {
+ return err
+ }
+
+ e.CipherFunc = CipherFunction(b[0])
+ e.Key = b[1 : len(b)-2]
+ expectedChecksum := uint16(b[len(b)-2])<<8 | uint16(b[len(b)-1])
+ checksum := checksumKeyMaterial(e.Key)
+ if checksum != expectedChecksum {
+ return error.StructuralError("EncryptedKey checksum incorrect")
+ }
+
+ return nil
+}
+
+// SerializeEncryptedKey serializes an encrypted key packet to w that contains
+// key, encrypted to pub.
+func SerializeEncryptedKey(w io.Writer, rand io.Reader, pub *PublicKey, cipherFunc CipherFunction, key []byte) os.Error {
+ var buf [10]byte
+ buf[0] = encryptedKeyVersion
+ binary.BigEndian.PutUint64(buf[1:9], pub.KeyId)
+ buf[9] = byte(pub.PubKeyAlgo)
+
+ keyBlock := make([]byte, 1 /* cipher type */ +len(key)+2 /* checksum */ )
+ keyBlock[0] = byte(cipherFunc)
+ copy(keyBlock[1:], key)
+ checksum := checksumKeyMaterial(key)
+ keyBlock[1+len(key)] = byte(checksum >> 8)
+ keyBlock[1+len(key)+1] = byte(checksum)
+
+ switch pub.PubKeyAlgo {
+ case PubKeyAlgoRSA, PubKeyAlgoRSAEncryptOnly:
+ return serializeEncryptedKeyRSA(w, rand, buf, pub.PublicKey.(*rsa.PublicKey), keyBlock)
+ case PubKeyAlgoElGamal:
+ return serializeEncryptedKeyElGamal(w, rand, buf, pub.PublicKey.(*elgamal.PublicKey), keyBlock)
+ case PubKeyAlgoDSA, PubKeyAlgoRSASignOnly:
+ return error.InvalidArgumentError("cannot encrypt to public key of type " + strconv.Itoa(int(pub.PubKeyAlgo)))
+ }
+
+ return error.UnsupportedError("encrypting a key to public key of type " + strconv.Itoa(int(pub.PubKeyAlgo)))
+}
+
+func serializeEncryptedKeyRSA(w io.Writer, rand io.Reader, header [10]byte, pub *rsa.PublicKey, keyBlock []byte) os.Error {
+ cipherText, err := rsa.EncryptPKCS1v15(rand, pub, keyBlock)
+ if err != nil {
+ return error.InvalidArgumentError("RSA encryption failed: " + err.String())
+ }
+
+ packetLen := 10 /* header length */ + 2 /* mpi size */ + len(cipherText)
+
+ err = serializeHeader(w, packetTypeEncryptedKey, packetLen)
+ if err != nil {
+ return err
+ }
+ _, err = w.Write(header[:])
+ if err != nil {
+ return err
+ }
+ return writeMPI(w, 8*uint16(len(cipherText)), cipherText)
+}
+
+func serializeEncryptedKeyElGamal(w io.Writer, rand io.Reader, header [10]byte, pub *elgamal.PublicKey, keyBlock []byte) os.Error {
+ c1, c2, err := elgamal.Encrypt(rand, pub, keyBlock)
+ if err != nil {
+ return error.InvalidArgumentError("ElGamal encryption failed: " + err.String())
+ }
+
+ packetLen := 10 /* header length */
+ packetLen += 2 /* mpi size */ + (c1.BitLen()+7)/8
+ packetLen += 2 /* mpi size */ + (c2.BitLen()+7)/8
+
+ err = serializeHeader(w, packetTypeEncryptedKey, packetLen)
+ if err != nil {
+ return err
+ }
+ _, err = w.Write(header[:])
+ if err != nil {
+ return err
+ }
+ err = writeBig(w, c1)
+ if err != nil {
+ return err
+ }
+ return writeBig(w, c2)
+}
diff --git a/src/pkg/crypto/openpgp/packet/encrypted_key_test.go b/src/pkg/crypto/openpgp/packet/encrypted_key_test.go
new file mode 100644
index 000000000..b402245bd
--- /dev/null
+++ b/src/pkg/crypto/openpgp/packet/encrypted_key_test.go
@@ -0,0 +1,126 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package packet
+
+import (
+ "big"
+ "bytes"
+ "crypto/rand"
+ "crypto/rsa"
+ "fmt"
+ "testing"
+)
+
+func bigFromBase10(s string) *big.Int {
+ b, ok := new(big.Int).SetString(s, 10)
+ if !ok {
+ panic("bigFromBase10 failed")
+ }
+ return b
+}
+
+var encryptedKeyPub = rsa.PublicKey{
+ E: 65537,
+ N: bigFromBase10("115804063926007623305902631768113868327816898845124614648849934718568541074358183759250136204762053879858102352159854352727097033322663029387610959884180306668628526686121021235757016368038585212410610742029286439607686208110250133174279811431933746643015923132833417396844716207301518956640020862630546868823"),
+}
+
+var encryptedKeyRSAPriv = &rsa.PrivateKey{
+ PublicKey: encryptedKeyPub,
+ D: bigFromBase10("32355588668219869544751561565313228297765464314098552250409557267371233892496951383426602439009993875125222579159850054973310859166139474359774543943714622292329487391199285040721944491839695981199720170366763547754915493640685849961780092241140181198779299712578774460837139360803883139311171713302987058393"),
+}
+
+var encryptedKeyPriv = &PrivateKey{
+ PublicKey: PublicKey{
+ PubKeyAlgo: PubKeyAlgoRSA,
+ },
+ PrivateKey: encryptedKeyRSAPriv,
+}
+
+func TestDecryptingEncryptedKey(t *testing.T) {
+ const encryptedKeyHex = "c18c032a67d68660df41c70104005789d0de26b6a50c985a02a13131ca829c413a35d0e6fa8d6842599252162808ac7439c72151c8c6183e76923fe3299301414d0c25a2f06a2257db3839e7df0ec964773f6e4c4ac7ff3b48c444237166dd46ba8ff443a5410dc670cb486672fdbe7c9dfafb75b4fea83af3a204fe2a7dfa86bd20122b4f3d2646cbeecb8f7be8"
+ const expectedKeyHex = "d930363f7e0308c333b9618617ea728963d8df993665ae7be1092d4926fd864b"
+
+ p, err := Read(readerFromHex(encryptedKeyHex))
+ if err != nil {
+ t.Errorf("error from Read: %s", err)
+ return
+ }
+ ek, ok := p.(*EncryptedKey)
+ if !ok {
+ t.Errorf("didn't parse an EncryptedKey, got %#v", p)
+ return
+ }
+
+ if ek.KeyId != 0x2a67d68660df41c7 || ek.Algo != PubKeyAlgoRSA {
+ t.Errorf("unexpected EncryptedKey contents: %#v", ek)
+ return
+ }
+
+ err = ek.Decrypt(encryptedKeyPriv)
+ if err != nil {
+ t.Errorf("error from Decrypt: %s", err)
+ return
+ }
+
+ if ek.CipherFunc != CipherAES256 {
+ t.Errorf("unexpected EncryptedKey contents: %#v", ek)
+ return
+ }
+
+ keyHex := fmt.Sprintf("%x", ek.Key)
+ if keyHex != expectedKeyHex {
+ t.Errorf("bad key, got %s want %x", keyHex, expectedKeyHex)
+ }
+}
+
+func TestEncryptingEncryptedKey(t *testing.T) {
+ key := []byte{1, 2, 3, 4}
+ const expectedKeyHex = "01020304"
+ const keyId = 42
+
+ pub := &PublicKey{
+ PublicKey: &encryptedKeyPub,
+ KeyId: keyId,
+ PubKeyAlgo: PubKeyAlgoRSAEncryptOnly,
+ }
+
+ buf := new(bytes.Buffer)
+ err := SerializeEncryptedKey(buf, rand.Reader, pub, CipherAES128, key)
+ if err != nil {
+ t.Errorf("error writing encrypted key packet: %s", err)
+ }
+
+ p, err := Read(buf)
+ if err != nil {
+ t.Errorf("error from Read: %s", err)
+ return
+ }
+ ek, ok := p.(*EncryptedKey)
+ if !ok {
+ t.Errorf("didn't parse an EncryptedKey, got %#v", p)
+ return
+ }
+
+ if ek.KeyId != keyId || ek.Algo != PubKeyAlgoRSAEncryptOnly {
+ t.Errorf("unexpected EncryptedKey contents: %#v", ek)
+ return
+ }
+
+ err = ek.Decrypt(encryptedKeyPriv)
+ if err != nil {
+ t.Errorf("error from Decrypt: %s", err)
+ return
+ }
+
+ if ek.CipherFunc != CipherAES128 {
+ t.Errorf("unexpected EncryptedKey contents: %#v", ek)
+ return
+ }
+
+ keyHex := fmt.Sprintf("%x", ek.Key)
+ if keyHex != expectedKeyHex {
+ t.Errorf("bad key, got %s want %x", keyHex, expectedKeyHex)
+ }
+}
diff --git a/src/pkg/crypto/openpgp/packet/literal.go b/src/pkg/crypto/openpgp/packet/literal.go
new file mode 100644
index 000000000..9411572d7
--- /dev/null
+++ b/src/pkg/crypto/openpgp/packet/literal.go
@@ -0,0 +1,90 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package packet
+
+import (
+ "encoding/binary"
+ "io"
+ "os"
+)
+
+// LiteralData represents an encrypted file. See RFC 4880, section 5.9.
+type LiteralData struct {
+ IsBinary bool
+ FileName string
+ Time uint32 // Unix epoch time. Either creation time or modification time. 0 means undefined.
+ Body io.Reader
+}
+
+// ForEyesOnly returns whether the contents of the LiteralData have been marked
+// as especially sensitive.
+func (l *LiteralData) ForEyesOnly() bool {
+ return l.FileName == "_CONSOLE"
+}
+
+func (l *LiteralData) parse(r io.Reader) (err os.Error) {
+ var buf [256]byte
+
+ _, err = readFull(r, buf[:2])
+ if err != nil {
+ return
+ }
+
+ l.IsBinary = buf[0] == 'b'
+ fileNameLen := int(buf[1])
+
+ _, err = readFull(r, buf[:fileNameLen])
+ if err != nil {
+ return
+ }
+
+ l.FileName = string(buf[:fileNameLen])
+
+ _, err = readFull(r, buf[:4])
+ if err != nil {
+ return
+ }
+
+ l.Time = binary.BigEndian.Uint32(buf[:4])
+ l.Body = r
+ return
+}
+
+// SerializeLiteral serializes a literal data packet to w and returns a
+// WriteCloser to which the data itself can be written and which MUST be closed
+// on completion. The fileName is truncated to 255 bytes.
+func SerializeLiteral(w io.WriteCloser, isBinary bool, fileName string, time uint32) (plaintext io.WriteCloser, err os.Error) {
+ var buf [4]byte
+ buf[0] = 't'
+ if isBinary {
+ buf[0] = 'b'
+ }
+ if len(fileName) > 255 {
+ fileName = fileName[:255]
+ }
+ buf[1] = byte(len(fileName))
+
+ inner, err := serializeStreamHeader(w, packetTypeLiteralData)
+ if err != nil {
+ return
+ }
+
+ _, err = inner.Write(buf[:2])
+ if err != nil {
+ return
+ }
+ _, err = inner.Write([]byte(fileName))
+ if err != nil {
+ return
+ }
+ binary.BigEndian.PutUint32(buf[:], time)
+ _, err = inner.Write(buf[:])
+ if err != nil {
+ return
+ }
+
+ plaintext = inner
+ return
+}
diff --git a/src/pkg/crypto/openpgp/packet/one_pass_signature.go b/src/pkg/crypto/openpgp/packet/one_pass_signature.go
new file mode 100644
index 000000000..ca826e4f4
--- /dev/null
+++ b/src/pkg/crypto/openpgp/packet/one_pass_signature.go
@@ -0,0 +1,74 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package packet
+
+import (
+ "crypto"
+ "crypto/openpgp/error"
+ "crypto/openpgp/s2k"
+ "encoding/binary"
+ "io"
+ "os"
+ "strconv"
+)
+
+// OnePassSignature represents a one-pass signature packet. See RFC 4880,
+// section 5.4.
+type OnePassSignature struct {
+ SigType SignatureType
+ Hash crypto.Hash
+ PubKeyAlgo PublicKeyAlgorithm
+ KeyId uint64
+ IsLast bool
+}
+
+const onePassSignatureVersion = 3
+
+func (ops *OnePassSignature) parse(r io.Reader) (err os.Error) {
+ var buf [13]byte
+
+ _, err = readFull(r, buf[:])
+ if err != nil {
+ return
+ }
+ if buf[0] != onePassSignatureVersion {
+ err = error.UnsupportedError("one-pass-signature packet version " + strconv.Itoa(int(buf[0])))
+ }
+
+ var ok bool
+ ops.Hash, ok = s2k.HashIdToHash(buf[2])
+ if !ok {
+ return error.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
+}
+
+// Serialize marshals the given OnePassSignature to w.
+func (ops *OnePassSignature) Serialize(w io.Writer) os.Error {
+ var buf [13]byte
+ buf[0] = onePassSignatureVersion
+ buf[1] = uint8(ops.SigType)
+ var ok bool
+ buf[2], ok = s2k.HashToHashId(ops.Hash)
+ if !ok {
+ return error.UnsupportedError("hash type: " + strconv.Itoa(int(ops.Hash)))
+ }
+ buf[3] = uint8(ops.PubKeyAlgo)
+ binary.BigEndian.PutUint64(buf[4:12], ops.KeyId)
+ if ops.IsLast {
+ buf[12] = 1
+ }
+
+ if err := serializeHeader(w, packetTypeOnePassSignature, len(buf)); err != nil {
+ return err
+ }
+ _, err := w.Write(buf[:])
+ return err
+}
diff --git a/src/pkg/crypto/openpgp/packet/packet.go b/src/pkg/crypto/openpgp/packet/packet.go
new file mode 100644
index 000000000..1d7297e38
--- /dev/null
+++ b/src/pkg/crypto/openpgp/packet/packet.go
@@ -0,0 +1,483 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package packet implements parsing and serialization of OpenPGP packets, as
+// specified in RFC 4880.
+package packet
+
+import (
+ "big"
+ "crypto/aes"
+ "crypto/cast5"
+ "crypto/cipher"
+ "crypto/openpgp/error"
+ "io"
+ "os"
+)
+
+// readFull is the same as io.ReadFull except that reading zero bytes returns
+// ErrUnexpectedEOF rather than EOF.
+func readFull(r io.Reader, buf []byte) (n int, err os.Error) {
+ n, err = io.ReadFull(r, buf)
+ if err == os.EOF {
+ err = io.ErrUnexpectedEOF
+ }
+ return
+}
+
+// readLength reads an OpenPGP length from r. See RFC 4880, section 4.2.2.
+func readLength(r io.Reader) (length int64, isPartial bool, err os.Error) {
+ var buf [4]byte
+ _, err = readFull(r, buf[:1])
+ if err != nil {
+ return
+ }
+ switch {
+ case buf[0] < 192:
+ length = int64(buf[0])
+ case buf[0] < 224:
+ length = int64(buf[0]-192) << 8
+ _, err = readFull(r, buf[0:1])
+ if err != nil {
+ return
+ }
+ length += int64(buf[0]) + 192
+ case buf[0] < 255:
+ length = int64(1) << (buf[0] & 0x1f)
+ isPartial = true
+ default:
+ _, err = readFull(r, buf[0:4])
+ if err != nil {
+ return
+ }
+ length = int64(buf[0])<<24 |
+ int64(buf[1])<<16 |
+ int64(buf[2])<<8 |
+ int64(buf[3])
+ }
+ return
+}
+
+// partialLengthReader wraps an io.Reader and handles OpenPGP partial lengths.
+// The continuation lengths are parsed and removed from the stream and EOF is
+// returned at the end of the packet. See RFC 4880, section 4.2.2.4.
+type partialLengthReader struct {
+ r io.Reader
+ remaining int64
+ isPartial bool
+}
+
+func (r *partialLengthReader) Read(p []byte) (n int, err os.Error) {
+ for r.remaining == 0 {
+ if !r.isPartial {
+ return 0, os.EOF
+ }
+ r.remaining, r.isPartial, err = readLength(r.r)
+ if err != nil {
+ return 0, err
+ }
+ }
+
+ toRead := int64(len(p))
+ if toRead > r.remaining {
+ toRead = r.remaining
+ }
+
+ n, err = r.r.Read(p[:int(toRead)])
+ r.remaining -= int64(n)
+ if n < int(toRead) && err == os.EOF {
+ err = io.ErrUnexpectedEOF
+ }
+ return
+}
+
+// partialLengthWriter writes a stream of data using OpenPGP partial lengths.
+// See RFC 4880, section 4.2.2.4.
+type partialLengthWriter struct {
+ w io.WriteCloser
+ lengthByte [1]byte
+}
+
+func (w *partialLengthWriter) Write(p []byte) (n int, err os.Error) {
+ for len(p) > 0 {
+ for power := uint(14); power < 32; power-- {
+ l := 1 << power
+ if len(p) >= l {
+ w.lengthByte[0] = 224 + uint8(power)
+ _, err = w.w.Write(w.lengthByte[:])
+ if err != nil {
+ return
+ }
+ var m int
+ m, err = w.w.Write(p[:l])
+ n += m
+ if err != nil {
+ return
+ }
+ p = p[l:]
+ break
+ }
+ }
+ }
+ return
+}
+
+func (w *partialLengthWriter) Close() os.Error {
+ w.lengthByte[0] = 0
+ _, err := w.w.Write(w.lengthByte[:])
+ if err != nil {
+ return err
+ }
+ return w.w.Close()
+}
+
+// A spanReader is an io.LimitReader, but it returns ErrUnexpectedEOF if the
+// underlying Reader returns EOF before the limit has been reached.
+type spanReader struct {
+ r io.Reader
+ n int64
+}
+
+func (l *spanReader) Read(p []byte) (n int, err os.Error) {
+ if l.n <= 0 {
+ return 0, os.EOF
+ }
+ if int64(len(p)) > l.n {
+ p = p[0:l.n]
+ }
+ n, err = l.r.Read(p)
+ l.n -= int64(n)
+ if l.n > 0 && err == os.EOF {
+ err = io.ErrUnexpectedEOF
+ }
+ return
+}
+
+// readHeader parses a packet header and returns an io.Reader which will return
+// the contents of the packet. See RFC 4880, section 4.2.
+func readHeader(r io.Reader) (tag packetType, length int64, contents io.Reader, err os.Error) {
+ var buf [4]byte
+ _, err = io.ReadFull(r, buf[:1])
+ if err != nil {
+ return
+ }
+ if buf[0]&0x80 == 0 {
+ err = error.StructuralError("tag byte does not have MSB set")
+ return
+ }
+ if buf[0]&0x40 == 0 {
+ // Old format packet
+ tag = packetType((buf[0] & 0x3f) >> 2)
+ lengthType := buf[0] & 3
+ if lengthType == 3 {
+ length = -1
+ contents = r
+ return
+ }
+ lengthBytes := 1 << lengthType
+ _, err = readFull(r, buf[0:lengthBytes])
+ if err != nil {
+ return
+ }
+ for i := 0; i < lengthBytes; i++ {
+ length <<= 8
+ length |= int64(buf[i])
+ }
+ contents = &spanReader{r, length}
+ return
+ }
+
+ // New format packet
+ tag = packetType(buf[0] & 0x3f)
+ length, isPartial, err := readLength(r)
+ if err != nil {
+ return
+ }
+ if isPartial {
+ contents = &partialLengthReader{
+ remaining: length,
+ isPartial: true,
+ r: r,
+ }
+ length = -1
+ } else {
+ contents = &spanReader{r, length}
+ }
+ return
+}
+
+// serializeHeader writes an OpenPGP packet header to w. See RFC 4880, section
+// 4.2.
+func serializeHeader(w io.Writer, ptype packetType, length int) (err os.Error) {
+ var buf [6]byte
+ var n int
+
+ buf[0] = 0x80 | 0x40 | byte(ptype)
+ if length < 192 {
+ buf[1] = byte(length)
+ n = 2
+ } else if length < 8384 {
+ length -= 192
+ buf[1] = 192 + byte(length>>8)
+ buf[2] = byte(length)
+ n = 3
+ } else {
+ buf[1] = 255
+ buf[2] = byte(length >> 24)
+ buf[3] = byte(length >> 16)
+ buf[4] = byte(length >> 8)
+ buf[5] = byte(length)
+ n = 6
+ }
+
+ _, err = w.Write(buf[:n])
+ return
+}
+
+// serializeStreamHeader writes an OpenPGP packet header to w where the
+// length of the packet is unknown. It returns a io.WriteCloser which can be
+// used to write the contents of the packet. See RFC 4880, section 4.2.
+func serializeStreamHeader(w io.WriteCloser, ptype packetType) (out io.WriteCloser, err os.Error) {
+ var buf [1]byte
+ buf[0] = 0x80 | 0x40 | byte(ptype)
+ _, err = w.Write(buf[:])
+ if err != nil {
+ return
+ }
+ out = &partialLengthWriter{w: w}
+ return
+}
+
+// Packet represents an OpenPGP packet. Users are expected to try casting
+// instances of this interface to specific packet types.
+type Packet interface {
+ parse(io.Reader) os.Error
+}
+
+// consumeAll reads from the given Reader until error, returning the number of
+// bytes read.
+func consumeAll(r io.Reader) (n int64, err os.Error) {
+ var m int
+ var buf [1024]byte
+
+ for {
+ m, err = r.Read(buf[:])
+ n += int64(m)
+ if err == os.EOF {
+ err = nil
+ return
+ }
+ if err != nil {
+ return
+ }
+ }
+
+ panic("unreachable")
+}
+
+// packetType represents the numeric ids of the different OpenPGP packet types. See
+// http://www.iana.org/assignments/pgp-parameters/pgp-parameters.xhtml#pgp-parameters-2
+type packetType uint8
+
+const (
+ packetTypeEncryptedKey packetType = 1
+ packetTypeSignature packetType = 2
+ packetTypeSymmetricKeyEncrypted packetType = 3
+ packetTypeOnePassSignature packetType = 4
+ packetTypePrivateKey packetType = 5
+ packetTypePublicKey packetType = 6
+ packetTypePrivateSubkey packetType = 7
+ packetTypeCompressed packetType = 8
+ packetTypeSymmetricallyEncrypted packetType = 9
+ packetTypeLiteralData packetType = 11
+ packetTypeUserId packetType = 13
+ packetTypePublicSubkey packetType = 14
+ packetTypeSymmetricallyEncryptedMDC packetType = 18
+)
+
+// Read reads a single OpenPGP packet from the given io.Reader. If there is an
+// error parsing a packet, the whole packet is consumed from the input.
+func Read(r io.Reader) (p Packet, err os.Error) {
+ tag, _, contents, err := readHeader(r)
+ if err != nil {
+ return
+ }
+
+ switch tag {
+ case packetTypeEncryptedKey:
+ p = new(EncryptedKey)
+ case packetTypeSignature:
+ p = new(Signature)
+ case packetTypeSymmetricKeyEncrypted:
+ p = new(SymmetricKeyEncrypted)
+ case packetTypeOnePassSignature:
+ p = new(OnePassSignature)
+ case packetTypePrivateKey, packetTypePrivateSubkey:
+ pk := new(PrivateKey)
+ if tag == packetTypePrivateSubkey {
+ pk.IsSubkey = true
+ }
+ p = pk
+ case packetTypePublicKey, packetTypePublicSubkey:
+ pk := new(PublicKey)
+ if tag == packetTypePublicSubkey {
+ pk.IsSubkey = true
+ }
+ p = pk
+ case packetTypeCompressed:
+ p = new(Compressed)
+ case packetTypeSymmetricallyEncrypted:
+ p = new(SymmetricallyEncrypted)
+ case packetTypeLiteralData:
+ p = new(LiteralData)
+ case packetTypeUserId:
+ p = new(UserId)
+ case packetTypeSymmetricallyEncryptedMDC:
+ se := new(SymmetricallyEncrypted)
+ se.MDC = true
+ p = se
+ default:
+ err = error.UnknownPacketTypeError(tag)
+ }
+ if p != nil {
+ err = p.parse(contents)
+ }
+ if err != nil {
+ consumeAll(contents)
+ }
+ return
+}
+
+// SignatureType represents the different semantic meanings of an OpenPGP
+// signature. See RFC 4880, section 5.2.1.
+type SignatureType uint8
+
+const (
+ SigTypeBinary SignatureType = 0
+ SigTypeText = 1
+ SigTypeGenericCert = 0x10
+ SigTypePersonaCert = 0x11
+ SigTypeCasualCert = 0x12
+ SigTypePositiveCert = 0x13
+ SigTypeSubkeyBinding = 0x18
+)
+
+// PublicKeyAlgorithm represents the different public key system specified for
+// OpenPGP. See
+// http://www.iana.org/assignments/pgp-parameters/pgp-parameters.xhtml#pgp-parameters-12
+type PublicKeyAlgorithm uint8
+
+const (
+ PubKeyAlgoRSA PublicKeyAlgorithm = 1
+ PubKeyAlgoRSAEncryptOnly PublicKeyAlgorithm = 2
+ PubKeyAlgoRSASignOnly PublicKeyAlgorithm = 3
+ PubKeyAlgoElGamal PublicKeyAlgorithm = 16
+ PubKeyAlgoDSA PublicKeyAlgorithm = 17
+)
+
+// CanEncrypt returns true if it's possible to encrypt a message to a public
+// key of the given type.
+func (pka PublicKeyAlgorithm) CanEncrypt() bool {
+ switch pka {
+ case PubKeyAlgoRSA, PubKeyAlgoRSAEncryptOnly, PubKeyAlgoElGamal:
+ return true
+ }
+ return false
+}
+
+// CanSign returns true if it's possible for a public key of the given type to
+// sign a message.
+func (pka PublicKeyAlgorithm) CanSign() bool {
+ switch pka {
+ case PubKeyAlgoRSA, PubKeyAlgoRSASignOnly, PubKeyAlgoDSA:
+ return true
+ }
+ return false
+}
+
+// CipherFunction represents the different block ciphers specified for OpenPGP. See
+// http://www.iana.org/assignments/pgp-parameters/pgp-parameters.xhtml#pgp-parameters-13
+type CipherFunction uint8
+
+const (
+ CipherCAST5 CipherFunction = 3
+ CipherAES128 CipherFunction = 7
+ CipherAES192 CipherFunction = 8
+ CipherAES256 CipherFunction = 9
+)
+
+// KeySize returns the key size, in bytes, of cipher.
+func (cipher CipherFunction) KeySize() int {
+ switch cipher {
+ case CipherCAST5:
+ return cast5.KeySize
+ case CipherAES128:
+ return 16
+ case CipherAES192:
+ return 24
+ case CipherAES256:
+ return 32
+ }
+ return 0
+}
+
+// blockSize returns the block size, in bytes, of cipher.
+func (cipher CipherFunction) blockSize() int {
+ switch cipher {
+ case CipherCAST5:
+ return 8
+ case CipherAES128, CipherAES192, CipherAES256:
+ return 16
+ }
+ return 0
+}
+
+// new returns a fresh instance of the given cipher.
+func (cipher CipherFunction) new(key []byte) (block cipher.Block) {
+ switch cipher {
+ case CipherCAST5:
+ block, _ = cast5.NewCipher(key)
+ case CipherAES128, CipherAES192, CipherAES256:
+ block, _ = aes.NewCipher(key)
+ }
+ return
+}
+
+// readMPI reads a big integer from r. The bit length returned is the bit
+// length that was specified in r. This is preserved so that the integer can be
+// reserialized exactly.
+func readMPI(r io.Reader) (mpi []byte, bitLength uint16, err os.Error) {
+ var buf [2]byte
+ _, err = readFull(r, buf[0:])
+ if err != nil {
+ return
+ }
+ bitLength = uint16(buf[0])<<8 | uint16(buf[1])
+ numBytes := (int(bitLength) + 7) / 8
+ mpi = make([]byte, numBytes)
+ _, err = readFull(r, mpi)
+ return
+}
+
+// mpiLength returns the length of the given *big.Int when serialized as an
+// MPI.
+func mpiLength(n *big.Int) (mpiLengthInBytes int) {
+ mpiLengthInBytes = 2 /* MPI length */
+ mpiLengthInBytes += (n.BitLen() + 7) / 8
+ return
+}
+
+// writeMPI serializes a big integer to w.
+func writeMPI(w io.Writer, bitLength uint16, mpiBytes []byte) (err os.Error) {
+ _, err = w.Write([]byte{byte(bitLength >> 8), byte(bitLength)})
+ if err == nil {
+ _, err = w.Write(mpiBytes)
+ }
+ return
+}
+
+// writeBig serializes a *big.Int to w.
+func writeBig(w io.Writer, i *big.Int) os.Error {
+ return writeMPI(w, uint16(i.BitLen()), i.Bytes())
+}
diff --git a/src/pkg/crypto/openpgp/packet/packet_test.go b/src/pkg/crypto/openpgp/packet/packet_test.go
new file mode 100644
index 000000000..23d9978ae
--- /dev/null
+++ b/src/pkg/crypto/openpgp/packet/packet_test.go
@@ -0,0 +1,256 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package packet
+
+import (
+ "bytes"
+ "crypto/openpgp/error"
+ "encoding/hex"
+ "fmt"
+ "io"
+ "io/ioutil"
+ "os"
+ "testing"
+)
+
+func TestReadFull(t *testing.T) {
+ var out [4]byte
+
+ b := bytes.NewBufferString("foo")
+ n, err := readFull(b, out[:3])
+ if n != 3 || err != nil {
+ t.Errorf("full read failed n:%d err:%s", n, err)
+ }
+
+ b = bytes.NewBufferString("foo")
+ n, err = readFull(b, out[:4])
+ if n != 3 || err != io.ErrUnexpectedEOF {
+ t.Errorf("partial read failed n:%d err:%s", n, err)
+ }
+
+ b = bytes.NewBuffer(nil)
+ n, err = readFull(b, out[:3])
+ if n != 0 || err != io.ErrUnexpectedEOF {
+ t.Errorf("empty read failed n:%d err:%s", n, err)
+ }
+}
+
+func readerFromHex(s string) io.Reader {
+ data, err := hex.DecodeString(s)
+ if err != nil {
+ panic("readerFromHex: bad input")
+ }
+ return bytes.NewBuffer(data)
+}
+
+var readLengthTests = []struct {
+ hexInput string
+ length int64
+ isPartial bool
+ err os.Error
+}{
+ {"", 0, false, io.ErrUnexpectedEOF},
+ {"1f", 31, false, nil},
+ {"c0", 0, false, io.ErrUnexpectedEOF},
+ {"c101", 256 + 1 + 192, false, nil},
+ {"e0", 1, true, nil},
+ {"e1", 2, true, nil},
+ {"e2", 4, true, nil},
+ {"ff", 0, false, io.ErrUnexpectedEOF},
+ {"ff00", 0, false, io.ErrUnexpectedEOF},
+ {"ff0000", 0, false, io.ErrUnexpectedEOF},
+ {"ff000000", 0, false, io.ErrUnexpectedEOF},
+ {"ff00000000", 0, false, nil},
+ {"ff01020304", 16909060, false, nil},
+}
+
+func TestReadLength(t *testing.T) {
+ for i, test := range readLengthTests {
+ length, isPartial, err := readLength(readerFromHex(test.hexInput))
+ if test.err != nil {
+ if err != test.err {
+ t.Errorf("%d: expected different error got:%s want:%s", i, err, test.err)
+ }
+ continue
+ }
+ if err != nil {
+ t.Errorf("%d: unexpected error: %s", i, err)
+ continue
+ }
+ if length != test.length || isPartial != test.isPartial {
+ t.Errorf("%d: bad result got:(%d,%t) want:(%d,%t)", i, length, isPartial, test.length, test.isPartial)
+ }
+ }
+}
+
+var partialLengthReaderTests = []struct {
+ hexInput string
+ err os.Error
+ hexOutput string
+}{
+ {"e0", io.ErrUnexpectedEOF, ""},
+ {"e001", io.ErrUnexpectedEOF, ""},
+ {"e0010102", nil, "0102"},
+ {"ff00000000", nil, ""},
+ {"e10102e1030400", nil, "01020304"},
+ {"e101", io.ErrUnexpectedEOF, ""},
+}
+
+func TestPartialLengthReader(t *testing.T) {
+ for i, test := range partialLengthReaderTests {
+ r := &partialLengthReader{readerFromHex(test.hexInput), 0, true}
+ out, err := ioutil.ReadAll(r)
+ if test.err != nil {
+ if err != test.err {
+ t.Errorf("%d: expected different error got:%s want:%s", i, err, test.err)
+ }
+ continue
+ }
+ if err != nil {
+ t.Errorf("%d: unexpected error: %s", i, err)
+ continue
+ }
+
+ got := fmt.Sprintf("%x", out)
+ if got != test.hexOutput {
+ t.Errorf("%d: got:%s want:%s", i, test.hexOutput, got)
+ }
+ }
+}
+
+var readHeaderTests = []struct {
+ hexInput string
+ structuralError bool
+ unexpectedEOF bool
+ tag int
+ length int64
+ hexOutput string
+}{
+ {"", false, false, 0, 0, ""},
+ {"7f", true, false, 0, 0, ""},
+
+ // Old format headers
+ {"80", false, true, 0, 0, ""},
+ {"8001", false, true, 0, 1, ""},
+ {"800102", false, false, 0, 1, "02"},
+ {"81000102", false, false, 0, 1, "02"},
+ {"820000000102", false, false, 0, 1, "02"},
+ {"860000000102", false, false, 1, 1, "02"},
+ {"83010203", false, false, 0, -1, "010203"},
+
+ // New format headers
+ {"c0", false, true, 0, 0, ""},
+ {"c000", false, false, 0, 0, ""},
+ {"c00102", false, false, 0, 1, "02"},
+ {"c0020203", false, false, 0, 2, "0203"},
+ {"c00202", false, true, 0, 2, ""},
+ {"c3020203", false, false, 3, 2, "0203"},
+}
+
+func TestReadHeader(t *testing.T) {
+ for i, test := range readHeaderTests {
+ tag, length, contents, err := readHeader(readerFromHex(test.hexInput))
+ if test.structuralError {
+ if _, ok := err.(error.StructuralError); ok {
+ continue
+ }
+ t.Errorf("%d: expected StructuralError, got:%s", i, err)
+ continue
+ }
+ if err != nil {
+ if len(test.hexInput) == 0 && err == os.EOF {
+ continue
+ }
+ if !test.unexpectedEOF || err != io.ErrUnexpectedEOF {
+ t.Errorf("%d: unexpected error from readHeader: %s", i, err)
+ }
+ continue
+ }
+ if int(tag) != test.tag || length != test.length {
+ t.Errorf("%d: got:(%d,%d) want:(%d,%d)", i, int(tag), length, test.tag, test.length)
+ continue
+ }
+
+ body, err := ioutil.ReadAll(contents)
+ if err != nil {
+ if !test.unexpectedEOF || err != io.ErrUnexpectedEOF {
+ t.Errorf("%d: unexpected error from contents: %s", i, err)
+ }
+ continue
+ }
+ if test.unexpectedEOF {
+ t.Errorf("%d: expected ErrUnexpectedEOF from contents but got no error", i)
+ continue
+ }
+ got := fmt.Sprintf("%x", body)
+ if got != test.hexOutput {
+ t.Errorf("%d: got:%s want:%s", i, got, test.hexOutput)
+ }
+ }
+}
+
+func TestSerializeHeader(t *testing.T) {
+ tag := packetTypePublicKey
+ lengths := []int{0, 1, 2, 64, 192, 193, 8000, 8384, 8385, 10000}
+
+ for _, length := range lengths {
+ buf := bytes.NewBuffer(nil)
+ serializeHeader(buf, tag, length)
+ tag2, length2, _, err := readHeader(buf)
+ if err != nil {
+ t.Errorf("length %d, err: %s", length, err)
+ }
+ if tag2 != tag {
+ t.Errorf("length %d, tag incorrect (got %d, want %d)", length, tag2, tag)
+ }
+ if int(length2) != length {
+ t.Errorf("length %d, length incorrect (got %d)", length, length2)
+ }
+ }
+}
+
+func TestPartialLengths(t *testing.T) {
+ buf := bytes.NewBuffer(nil)
+ w := new(partialLengthWriter)
+ w.w = noOpCloser{buf}
+
+ const maxChunkSize = 64
+
+ var b [maxChunkSize]byte
+ var n uint8
+ for l := 1; l <= maxChunkSize; l++ {
+ for i := 0; i < l; i++ {
+ b[i] = n
+ n++
+ }
+ m, err := w.Write(b[:l])
+ if m != l {
+ t.Errorf("short write got: %d want: %d", m, l)
+ }
+ if err != nil {
+ t.Errorf("error from write: %s", err)
+ }
+ }
+ w.Close()
+
+ want := (maxChunkSize * (maxChunkSize + 1)) / 2
+ copyBuf := bytes.NewBuffer(nil)
+ r := &partialLengthReader{buf, 0, true}
+ m, err := io.Copy(copyBuf, r)
+ if m != int64(want) {
+ t.Errorf("short copy got: %d want: %d", m, want)
+ }
+ if err != nil {
+ t.Errorf("error from copy: %s", err)
+ }
+
+ copyBytes := copyBuf.Bytes()
+ for i := 0; i < want; i++ {
+ if copyBytes[i] != uint8(i) {
+ t.Errorf("bad pattern in copy at %d", i)
+ break
+ }
+ }
+}
diff --git a/src/pkg/crypto/openpgp/packet/private_key.go b/src/pkg/crypto/openpgp/packet/private_key.go
new file mode 100644
index 000000000..6f8133d98
--- /dev/null
+++ b/src/pkg/crypto/openpgp/packet/private_key.go
@@ -0,0 +1,301 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package packet
+
+import (
+ "big"
+ "bytes"
+ "crypto/cipher"
+ "crypto/dsa"
+ "crypto/openpgp/elgamal"
+ "crypto/openpgp/error"
+ "crypto/openpgp/s2k"
+ "crypto/rsa"
+ "crypto/sha1"
+ "io"
+ "io/ioutil"
+ "os"
+ "strconv"
+)
+
+// PrivateKey represents a possibly encrypted private key. See RFC 4880,
+// section 5.5.3.
+type PrivateKey struct {
+ PublicKey
+ Encrypted bool // if true then the private key is unavailable until Decrypt has been called.
+ encryptedData []byte
+ cipher CipherFunction
+ s2k func(out, in []byte)
+ PrivateKey interface{} // An *rsa.PrivateKey.
+ sha1Checksum bool
+ iv []byte
+}
+
+func NewRSAPrivateKey(currentTimeSecs uint32, priv *rsa.PrivateKey, isSubkey bool) *PrivateKey {
+ pk := new(PrivateKey)
+ pk.PublicKey = *NewRSAPublicKey(currentTimeSecs, &priv.PublicKey, isSubkey)
+ pk.PrivateKey = priv
+ return pk
+}
+
+func (pk *PrivateKey) parse(r io.Reader) (err os.Error) {
+ err = (&pk.PublicKey).parse(r)
+ if err != nil {
+ return
+ }
+ var buf [1]byte
+ _, err = readFull(r, buf[:])
+ if err != nil {
+ return
+ }
+
+ s2kType := buf[0]
+
+ switch s2kType {
+ case 0:
+ pk.s2k = nil
+ pk.Encrypted = false
+ case 254, 255:
+ _, err = readFull(r, buf[:])
+ if err != nil {
+ return
+ }
+ pk.cipher = CipherFunction(buf[0])
+ pk.Encrypted = true
+ pk.s2k, err = s2k.Parse(r)
+ if err != nil {
+ return
+ }
+ if s2kType == 254 {
+ pk.sha1Checksum = true
+ }
+ default:
+ return error.UnsupportedError("deprecated s2k function in private key")
+ }
+
+ if pk.Encrypted {
+ blockSize := pk.cipher.blockSize()
+ if blockSize == 0 {
+ return error.UnsupportedError("unsupported cipher in private key: " + strconv.Itoa(int(pk.cipher)))
+ }
+ pk.iv = make([]byte, blockSize)
+ _, err = readFull(r, pk.iv)
+ if err != nil {
+ return
+ }
+ }
+
+ pk.encryptedData, err = ioutil.ReadAll(r)
+ if err != nil {
+ return
+ }
+
+ if !pk.Encrypted {
+ return pk.parsePrivateKey(pk.encryptedData)
+ }
+
+ return
+}
+
+func mod64kHash(d []byte) uint16 {
+ h := uint16(0)
+ for i := 0; i < len(d); i += 2 {
+ v := uint16(d[i]) << 8
+ if i+1 < len(d) {
+ v += uint16(d[i+1])
+ }
+ h += v
+ }
+ return h
+}
+
+func (pk *PrivateKey) Serialize(w io.Writer) (err os.Error) {
+ // TODO(agl): support encrypted private keys
+ buf := bytes.NewBuffer(nil)
+ err = pk.PublicKey.serializeWithoutHeaders(buf)
+ if err != nil {
+ return
+ }
+ buf.WriteByte(0 /* no encryption */ )
+
+ privateKeyBuf := bytes.NewBuffer(nil)
+
+ switch priv := pk.PrivateKey.(type) {
+ case *rsa.PrivateKey:
+ err = serializeRSAPrivateKey(privateKeyBuf, priv)
+ default:
+ err = error.InvalidArgumentError("non-RSA private key")
+ }
+ if err != nil {
+ return
+ }
+
+ ptype := packetTypePrivateKey
+ contents := buf.Bytes()
+ privateKeyBytes := privateKeyBuf.Bytes()
+ if pk.IsSubkey {
+ ptype = packetTypePrivateSubkey
+ }
+ err = serializeHeader(w, ptype, len(contents)+len(privateKeyBytes)+2)
+ if err != nil {
+ return
+ }
+ _, err = w.Write(contents)
+ if err != nil {
+ return
+ }
+ _, err = w.Write(privateKeyBytes)
+ if err != nil {
+ return
+ }
+
+ checksum := mod64kHash(privateKeyBytes)
+ var checksumBytes [2]byte
+ checksumBytes[0] = byte(checksum >> 8)
+ checksumBytes[1] = byte(checksum)
+ _, err = w.Write(checksumBytes[:])
+
+ return
+}
+
+func serializeRSAPrivateKey(w io.Writer, priv *rsa.PrivateKey) os.Error {
+ err := writeBig(w, priv.D)
+ if err != nil {
+ return err
+ }
+ err = writeBig(w, priv.Primes[1])
+ if err != nil {
+ return err
+ }
+ err = writeBig(w, priv.Primes[0])
+ if err != nil {
+ return err
+ }
+ return writeBig(w, priv.Precomputed.Qinv)
+}
+
+// Decrypt decrypts an encrypted private key using a passphrase.
+func (pk *PrivateKey) Decrypt(passphrase []byte) os.Error {
+ if !pk.Encrypted {
+ return nil
+ }
+
+ key := make([]byte, pk.cipher.KeySize())
+ pk.s2k(key, passphrase)
+ block := pk.cipher.new(key)
+ cfb := cipher.NewCFBDecrypter(block, pk.iv)
+
+ data := pk.encryptedData
+ cfb.XORKeyStream(data, data)
+
+ if pk.sha1Checksum {
+ if len(data) < sha1.Size {
+ return error.StructuralError("truncated private key data")
+ }
+ h := sha1.New()
+ h.Write(data[:len(data)-sha1.Size])
+ sum := h.Sum()
+ if !bytes.Equal(sum, data[len(data)-sha1.Size:]) {
+ return error.StructuralError("private key checksum failure")
+ }
+ data = data[:len(data)-sha1.Size]
+ } else {
+ if len(data) < 2 {
+ return error.StructuralError("truncated private key data")
+ }
+ var sum uint16
+ for i := 0; i < len(data)-2; i++ {
+ sum += uint16(data[i])
+ }
+ if data[len(data)-2] != uint8(sum>>8) ||
+ data[len(data)-1] != uint8(sum) {
+ return error.StructuralError("private key checksum failure")
+ }
+ data = data[:len(data)-2]
+ }
+
+ return pk.parsePrivateKey(data)
+}
+
+func (pk *PrivateKey) parsePrivateKey(data []byte) (err os.Error) {
+ switch pk.PublicKey.PubKeyAlgo {
+ case PubKeyAlgoRSA, PubKeyAlgoRSASignOnly, PubKeyAlgoRSAEncryptOnly:
+ return pk.parseRSAPrivateKey(data)
+ case PubKeyAlgoDSA:
+ return pk.parseDSAPrivateKey(data)
+ case PubKeyAlgoElGamal:
+ return pk.parseElGamalPrivateKey(data)
+ }
+ panic("impossible")
+}
+
+func (pk *PrivateKey) parseRSAPrivateKey(data []byte) (err os.Error) {
+ rsaPub := pk.PublicKey.PublicKey.(*rsa.PublicKey)
+ rsaPriv := new(rsa.PrivateKey)
+ rsaPriv.PublicKey = *rsaPub
+
+ buf := bytes.NewBuffer(data)
+ d, _, err := readMPI(buf)
+ if err != nil {
+ return
+ }
+ p, _, err := readMPI(buf)
+ if err != nil {
+ return
+ }
+ q, _, err := readMPI(buf)
+ if err != nil {
+ return
+ }
+
+ rsaPriv.D = new(big.Int).SetBytes(d)
+ rsaPriv.Primes = make([]*big.Int, 2)
+ rsaPriv.Primes[0] = new(big.Int).SetBytes(p)
+ rsaPriv.Primes[1] = new(big.Int).SetBytes(q)
+ rsaPriv.Precompute()
+ pk.PrivateKey = rsaPriv
+ pk.Encrypted = false
+ pk.encryptedData = nil
+
+ return nil
+}
+
+func (pk *PrivateKey) parseDSAPrivateKey(data []byte) (err os.Error) {
+ dsaPub := pk.PublicKey.PublicKey.(*dsa.PublicKey)
+ dsaPriv := new(dsa.PrivateKey)
+ dsaPriv.PublicKey = *dsaPub
+
+ buf := bytes.NewBuffer(data)
+ x, _, err := readMPI(buf)
+ if err != nil {
+ return
+ }
+
+ dsaPriv.X = new(big.Int).SetBytes(x)
+ pk.PrivateKey = dsaPriv
+ pk.Encrypted = false
+ pk.encryptedData = nil
+
+ return nil
+}
+
+func (pk *PrivateKey) parseElGamalPrivateKey(data []byte) (err os.Error) {
+ pub := pk.PublicKey.PublicKey.(*elgamal.PublicKey)
+ priv := new(elgamal.PrivateKey)
+ priv.PublicKey = *pub
+
+ buf := bytes.NewBuffer(data)
+ x, _, err := readMPI(buf)
+ if err != nil {
+ return
+ }
+
+ priv.X = new(big.Int).SetBytes(x)
+ pk.PrivateKey = priv
+ pk.Encrypted = false
+ pk.encryptedData = nil
+
+ return nil
+}
diff --git a/src/pkg/crypto/openpgp/packet/private_key_test.go b/src/pkg/crypto/openpgp/packet/private_key_test.go
new file mode 100644
index 000000000..60eebaa6b
--- /dev/null
+++ b/src/pkg/crypto/openpgp/packet/private_key_test.go
@@ -0,0 +1,57 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package packet
+
+import (
+ "testing"
+)
+
+var privateKeyTests = []struct {
+ privateKeyHex string
+ creationTime uint32
+}{
+ {
+ privKeyRSAHex,
+ 0x4cc349a8,
+ },
+ {
+ privKeyElGamalHex,
+ 0x4df9ee1a,
+ },
+}
+
+func TestPrivateKeyRead(t *testing.T) {
+ for i, test := range privateKeyTests {
+ packet, err := Read(readerFromHex(test.privateKeyHex))
+ if err != nil {
+ t.Errorf("#%d: failed to parse: %s", i, err)
+ continue
+ }
+
+ privKey := packet.(*PrivateKey)
+
+ if !privKey.Encrypted {
+ t.Errorf("#%d: private key isn't encrypted", i)
+ continue
+ }
+
+ err = privKey.Decrypt([]byte("testing"))
+ if err != nil {
+ t.Errorf("#%d: failed to decrypt: %s", i, err)
+ continue
+ }
+
+ if privKey.CreationTime != test.creationTime || privKey.Encrypted {
+ t.Errorf("#%d: bad result, got: %#v", i, privKey)
+ }
+ }
+}
+
+// Generated with `gpg --export-secret-keys "Test Key 2"`
+const privKeyRSAHex = "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"
+
+// Generated by `gpg --export-secret-keys` followed by a manual extraction of
+// the ElGamal subkey from the packets.
+const privKeyElGamalHex = "9d0157044df9ee1a100400eb8e136a58ec39b582629cdadf830bc64e0a94ed8103ca8bb247b27b11b46d1d25297ef4bcc3071785ba0c0bedfe89eabc5287fcc0edf81ab5896c1c8e4b20d27d79813c7aede75320b33eaeeaa586edc00fd1036c10133e6ba0ff277245d0d59d04b2b3421b7244aca5f4a8d870c6f1c1fbff9e1c26699a860b9504f35ca1d700030503fd1ededd3b840795be6d9ccbe3c51ee42e2f39233c432b831ddd9c4e72b7025a819317e47bf94f9ee316d7273b05d5fcf2999c3a681f519b1234bbfa6d359b4752bd9c3f77d6b6456cde152464763414ca130f4e91d91041432f90620fec0e6d6b5116076c2985d5aeaae13be492b9b329efcaf7ee25120159a0a30cd976b42d7afe030302dae7eb80db744d4960c4df930d57e87fe81412eaace9f900e6c839817a614ddb75ba6603b9417c33ea7b6c93967dfa2bcff3fa3c74a5ce2c962db65b03aece14c96cbd0038fc"
diff --git a/src/pkg/crypto/openpgp/packet/public_key.go b/src/pkg/crypto/openpgp/packet/public_key.go
new file mode 100644
index 000000000..e6b0ae5f3
--- /dev/null
+++ b/src/pkg/crypto/openpgp/packet/public_key.go
@@ -0,0 +1,393 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package packet
+
+import (
+ "big"
+ "crypto/dsa"
+ "crypto/openpgp/elgamal"
+ "crypto/openpgp/error"
+ "crypto/rsa"
+ "crypto/sha1"
+ "encoding/binary"
+ "fmt"
+ "hash"
+ "io"
+ "os"
+ "strconv"
+)
+
+// PublicKey represents an OpenPGP public key. See RFC 4880, section 5.5.2.
+type PublicKey struct {
+ CreationTime uint32 // seconds since the epoch
+ PubKeyAlgo PublicKeyAlgorithm
+ PublicKey interface{} // Either a *rsa.PublicKey or *dsa.PublicKey
+ Fingerprint [20]byte
+ KeyId uint64
+ IsSubkey bool
+
+ n, e, p, q, g, y parsedMPI
+}
+
+func fromBig(n *big.Int) parsedMPI {
+ return parsedMPI{
+ bytes: n.Bytes(),
+ bitLength: uint16(n.BitLen()),
+ }
+}
+
+// NewRSAPublicKey returns a PublicKey that wraps the given rsa.PublicKey.
+func NewRSAPublicKey(creationTimeSecs uint32, pub *rsa.PublicKey, isSubkey bool) *PublicKey {
+ pk := &PublicKey{
+ CreationTime: creationTimeSecs,
+ PubKeyAlgo: PubKeyAlgoRSA,
+ PublicKey: pub,
+ IsSubkey: isSubkey,
+ n: fromBig(pub.N),
+ e: fromBig(big.NewInt(int64(pub.E))),
+ }
+
+ pk.setFingerPrintAndKeyId()
+ return pk
+}
+
+func (pk *PublicKey) parse(r io.Reader) (err os.Error) {
+ // RFC 4880, section 5.5.2
+ var buf [6]byte
+ _, err = readFull(r, buf[:])
+ if err != nil {
+ return
+ }
+ if buf[0] != 4 {
+ return error.UnsupportedError("public key version")
+ }
+ pk.CreationTime = uint32(buf[1])<<24 | uint32(buf[2])<<16 | uint32(buf[3])<<8 | uint32(buf[4])
+ pk.PubKeyAlgo = PublicKeyAlgorithm(buf[5])
+ switch pk.PubKeyAlgo {
+ case PubKeyAlgoRSA, PubKeyAlgoRSAEncryptOnly, PubKeyAlgoRSASignOnly:
+ err = pk.parseRSA(r)
+ case PubKeyAlgoDSA:
+ err = pk.parseDSA(r)
+ case PubKeyAlgoElGamal:
+ err = pk.parseElGamal(r)
+ default:
+ err = error.UnsupportedError("public key type: " + strconv.Itoa(int(pk.PubKeyAlgo)))
+ }
+ if err != nil {
+ return
+ }
+
+ pk.setFingerPrintAndKeyId()
+ return
+}
+
+func (pk *PublicKey) setFingerPrintAndKeyId() {
+ // RFC 4880, section 12.2
+ fingerPrint := sha1.New()
+ pk.SerializeSignaturePrefix(fingerPrint)
+ pk.serializeWithoutHeaders(fingerPrint)
+ copy(pk.Fingerprint[:], fingerPrint.Sum())
+ pk.KeyId = binary.BigEndian.Uint64(pk.Fingerprint[12:20])
+}
+
+// parseRSA parses RSA public key material from the given Reader. See RFC 4880,
+// section 5.5.2.
+func (pk *PublicKey) parseRSA(r io.Reader) (err os.Error) {
+ pk.n.bytes, pk.n.bitLength, err = readMPI(r)
+ if err != nil {
+ return
+ }
+ pk.e.bytes, pk.e.bitLength, err = readMPI(r)
+ if err != nil {
+ return
+ }
+
+ if len(pk.e.bytes) > 3 {
+ err = error.UnsupportedError("large public exponent")
+ return
+ }
+ rsa := &rsa.PublicKey{
+ N: new(big.Int).SetBytes(pk.n.bytes),
+ E: 0,
+ }
+ for i := 0; i < len(pk.e.bytes); i++ {
+ rsa.E <<= 8
+ rsa.E |= int(pk.e.bytes[i])
+ }
+ pk.PublicKey = rsa
+ return
+}
+
+// parseDSA parses DSA public key material from the given Reader. See RFC 4880,
+// section 5.5.2.
+func (pk *PublicKey) parseDSA(r io.Reader) (err os.Error) {
+ pk.p.bytes, pk.p.bitLength, err = readMPI(r)
+ if err != nil {
+ return
+ }
+ pk.q.bytes, pk.q.bitLength, err = readMPI(r)
+ if err != nil {
+ return
+ }
+ pk.g.bytes, pk.g.bitLength, err = readMPI(r)
+ if err != nil {
+ return
+ }
+ pk.y.bytes, pk.y.bitLength, err = readMPI(r)
+ if err != nil {
+ return
+ }
+
+ dsa := new(dsa.PublicKey)
+ dsa.P = new(big.Int).SetBytes(pk.p.bytes)
+ dsa.Q = new(big.Int).SetBytes(pk.q.bytes)
+ dsa.G = new(big.Int).SetBytes(pk.g.bytes)
+ dsa.Y = new(big.Int).SetBytes(pk.y.bytes)
+ pk.PublicKey = dsa
+ return
+}
+
+// parseElGamal parses ElGamal public key material from the given Reader. See
+// RFC 4880, section 5.5.2.
+func (pk *PublicKey) parseElGamal(r io.Reader) (err os.Error) {
+ pk.p.bytes, pk.p.bitLength, err = readMPI(r)
+ if err != nil {
+ return
+ }
+ pk.g.bytes, pk.g.bitLength, err = readMPI(r)
+ if err != nil {
+ return
+ }
+ pk.y.bytes, pk.y.bitLength, err = readMPI(r)
+ if err != nil {
+ return
+ }
+
+ elgamal := new(elgamal.PublicKey)
+ elgamal.P = new(big.Int).SetBytes(pk.p.bytes)
+ elgamal.G = new(big.Int).SetBytes(pk.g.bytes)
+ elgamal.Y = new(big.Int).SetBytes(pk.y.bytes)
+ pk.PublicKey = elgamal
+ return
+}
+
+// SerializeSignaturePrefix writes the prefix for this public key to the given Writer.
+// The prefix is used when calculating a signature over this public key. See
+// RFC 4880, section 5.2.4.
+func (pk *PublicKey) SerializeSignaturePrefix(h hash.Hash) {
+ var pLength uint16
+ switch pk.PubKeyAlgo {
+ case PubKeyAlgoRSA, PubKeyAlgoRSAEncryptOnly, PubKeyAlgoRSASignOnly:
+ pLength += 2 + uint16(len(pk.n.bytes))
+ pLength += 2 + uint16(len(pk.e.bytes))
+ case PubKeyAlgoDSA:
+ pLength += 2 + uint16(len(pk.p.bytes))
+ pLength += 2 + uint16(len(pk.q.bytes))
+ pLength += 2 + uint16(len(pk.g.bytes))
+ pLength += 2 + uint16(len(pk.y.bytes))
+ case PubKeyAlgoElGamal:
+ pLength += 2 + uint16(len(pk.p.bytes))
+ pLength += 2 + uint16(len(pk.g.bytes))
+ pLength += 2 + uint16(len(pk.y.bytes))
+ default:
+ panic("unknown public key algorithm")
+ }
+ pLength += 6
+ h.Write([]byte{0x99, byte(pLength >> 8), byte(pLength)})
+ return
+}
+
+func (pk *PublicKey) Serialize(w io.Writer) (err os.Error) {
+ length := 6 // 6 byte header
+
+ switch pk.PubKeyAlgo {
+ case PubKeyAlgoRSA, PubKeyAlgoRSAEncryptOnly, PubKeyAlgoRSASignOnly:
+ length += 2 + len(pk.n.bytes)
+ length += 2 + len(pk.e.bytes)
+ case PubKeyAlgoDSA:
+ length += 2 + len(pk.p.bytes)
+ length += 2 + len(pk.q.bytes)
+ length += 2 + len(pk.g.bytes)
+ length += 2 + len(pk.y.bytes)
+ case PubKeyAlgoElGamal:
+ length += 2 + len(pk.p.bytes)
+ length += 2 + len(pk.g.bytes)
+ length += 2 + len(pk.y.bytes)
+ default:
+ panic("unknown public key algorithm")
+ }
+
+ packetType := packetTypePublicKey
+ if pk.IsSubkey {
+ packetType = packetTypePublicSubkey
+ }
+ err = serializeHeader(w, packetType, length)
+ if err != nil {
+ return
+ }
+ return pk.serializeWithoutHeaders(w)
+}
+
+// serializeWithoutHeaders marshals the PublicKey to w in the form of an
+// OpenPGP public key packet, not including the packet header.
+func (pk *PublicKey) serializeWithoutHeaders(w io.Writer) (err os.Error) {
+ var buf [6]byte
+ buf[0] = 4
+ buf[1] = byte(pk.CreationTime >> 24)
+ buf[2] = byte(pk.CreationTime >> 16)
+ buf[3] = byte(pk.CreationTime >> 8)
+ buf[4] = byte(pk.CreationTime)
+ buf[5] = byte(pk.PubKeyAlgo)
+
+ _, err = w.Write(buf[:])
+ if err != nil {
+ return
+ }
+
+ switch pk.PubKeyAlgo {
+ case PubKeyAlgoRSA, PubKeyAlgoRSAEncryptOnly, PubKeyAlgoRSASignOnly:
+ return writeMPIs(w, pk.n, pk.e)
+ case PubKeyAlgoDSA:
+ return writeMPIs(w, pk.p, pk.q, pk.g, pk.y)
+ case PubKeyAlgoElGamal:
+ return writeMPIs(w, pk.p, pk.g, pk.y)
+ }
+ return error.InvalidArgumentError("bad public-key algorithm")
+}
+
+// CanSign returns true iff this public key can generate signatures
+func (pk *PublicKey) CanSign() bool {
+ return pk.PubKeyAlgo != PubKeyAlgoRSAEncryptOnly && pk.PubKeyAlgo != PubKeyAlgoElGamal
+}
+
+// VerifySignature returns nil iff sig is a valid signature, made by this
+// public key, of the data hashed into signed. signed is mutated by this call.
+func (pk *PublicKey) VerifySignature(signed hash.Hash, sig *Signature) (err os.Error) {
+ if !pk.CanSign() {
+ return error.InvalidArgumentError("public key cannot generate signatures")
+ }
+
+ signed.Write(sig.HashSuffix)
+ hashBytes := signed.Sum()
+
+ if hashBytes[0] != sig.HashTag[0] || hashBytes[1] != sig.HashTag[1] {
+ return error.SignatureError("hash tag doesn't match")
+ }
+
+ if pk.PubKeyAlgo != sig.PubKeyAlgo {
+ return error.InvalidArgumentError("public key and signature use different algorithms")
+ }
+
+ switch pk.PubKeyAlgo {
+ case PubKeyAlgoRSA, PubKeyAlgoRSASignOnly:
+ rsaPublicKey, _ := pk.PublicKey.(*rsa.PublicKey)
+ err = rsa.VerifyPKCS1v15(rsaPublicKey, sig.Hash, hashBytes, sig.RSASignature.bytes)
+ if err != nil {
+ return error.SignatureError("RSA verification failure")
+ }
+ return nil
+ case PubKeyAlgoDSA:
+ dsaPublicKey, _ := pk.PublicKey.(*dsa.PublicKey)
+ if !dsa.Verify(dsaPublicKey, hashBytes, new(big.Int).SetBytes(sig.DSASigR.bytes), new(big.Int).SetBytes(sig.DSASigS.bytes)) {
+ return error.SignatureError("DSA verification failure")
+ }
+ return nil
+ default:
+ panic("shouldn't happen")
+ }
+ panic("unreachable")
+}
+
+// keySignatureHash returns a Hash of the message that needs to be signed for
+// pk to assert a subkey relationship to signed.
+func keySignatureHash(pk, signed *PublicKey, sig *Signature) (h hash.Hash, err os.Error) {
+ h = sig.Hash.New()
+ if h == nil {
+ return nil, error.UnsupportedError("hash function")
+ }
+
+ // RFC 4880, section 5.2.4
+ pk.SerializeSignaturePrefix(h)
+ pk.serializeWithoutHeaders(h)
+ signed.SerializeSignaturePrefix(h)
+ signed.serializeWithoutHeaders(h)
+ return
+}
+
+// VerifyKeySignature returns nil iff sig is a valid signature, made by this
+// public key, of signed.
+func (pk *PublicKey) VerifyKeySignature(signed *PublicKey, sig *Signature) (err os.Error) {
+ h, err := keySignatureHash(pk, signed, sig)
+ if err != nil {
+ return err
+ }
+ return pk.VerifySignature(h, sig)
+}
+
+// userIdSignatureHash returns a Hash of the message that needs to be signed
+// to assert that pk is a valid key for id.
+func userIdSignatureHash(id string, pk *PublicKey, sig *Signature) (h hash.Hash, err os.Error) {
+ h = sig.Hash.New()
+ if h == nil {
+ return nil, error.UnsupportedError("hash function")
+ }
+
+ // RFC 4880, section 5.2.4
+ pk.SerializeSignaturePrefix(h)
+ pk.serializeWithoutHeaders(h)
+
+ var buf [5]byte
+ buf[0] = 0xb4
+ buf[1] = byte(len(id) >> 24)
+ buf[2] = byte(len(id) >> 16)
+ buf[3] = byte(len(id) >> 8)
+ buf[4] = byte(len(id))
+ h.Write(buf[:])
+ h.Write([]byte(id))
+
+ return
+}
+
+// VerifyUserIdSignature returns nil iff sig is a valid signature, made by this
+// public key, of id.
+func (pk *PublicKey) VerifyUserIdSignature(id string, sig *Signature) (err os.Error) {
+ h, err := userIdSignatureHash(id, pk, sig)
+ if err != nil {
+ return err
+ }
+ return pk.VerifySignature(h, sig)
+}
+
+// KeyIdString returns the public key's fingerprint in capital hex
+// (e.g. "6C7EE1B8621CC013").
+func (pk *PublicKey) KeyIdString() string {
+ return fmt.Sprintf("%X", pk.Fingerprint[12:20])
+}
+
+// KeyIdShortString returns the short form of public key's fingerprint
+// in capital hex, as shown by gpg --list-keys (e.g. "621CC013").
+func (pk *PublicKey) KeyIdShortString() string {
+ return fmt.Sprintf("%X", pk.Fingerprint[16:20])
+}
+
+// A parsedMPI is used to store the contents of a big integer, along with the
+// bit length that was specified in the original input. This allows the MPI to
+// be reserialized exactly.
+type parsedMPI struct {
+ bytes []byte
+ bitLength uint16
+}
+
+// writeMPIs is a utility function for serializing several big integers to the
+// given Writer.
+func writeMPIs(w io.Writer, mpis ...parsedMPI) (err os.Error) {
+ for _, mpi := range mpis {
+ err = writeMPI(w, mpi.bitLength, mpi.bytes)
+ if err != nil {
+ return
+ }
+ }
+ return
+}
diff --git a/src/pkg/crypto/openpgp/packet/public_key_test.go b/src/pkg/crypto/openpgp/packet/public_key_test.go
new file mode 100644
index 000000000..6e8bfbce6
--- /dev/null
+++ b/src/pkg/crypto/openpgp/packet/public_key_test.go
@@ -0,0 +1,98 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package packet
+
+import (
+ "bytes"
+ "encoding/hex"
+ "testing"
+)
+
+var pubKeyTests = []struct {
+ hexData string
+ hexFingerprint string
+ creationTime uint32
+ pubKeyAlgo PublicKeyAlgorithm
+ keyId uint64
+ keyIdString string
+ keyIdShort string
+}{
+ {rsaPkDataHex, rsaFingerprintHex, 0x4d3c5c10, PubKeyAlgoRSA, 0xa34d7e18c20c31bb, "A34D7E18C20C31BB", "C20C31BB"},
+ {dsaPkDataHex, dsaFingerprintHex, 0x4d432f89, PubKeyAlgoDSA, 0x8e8fbe54062f19ed, "8E8FBE54062F19ED", "062F19ED"},
+}
+
+func TestPublicKeyRead(t *testing.T) {
+ for i, test := range pubKeyTests {
+ packet, err := Read(readerFromHex(test.hexData))
+ if err != nil {
+ t.Errorf("#%d: Read error: %s", i, err)
+ continue
+ }
+ pk, ok := packet.(*PublicKey)
+ if !ok {
+ t.Errorf("#%d: failed to parse, got: %#v", i, packet)
+ continue
+ }
+ if pk.PubKeyAlgo != test.pubKeyAlgo {
+ t.Errorf("#%d: bad public key algorithm got:%x want:%x", i, pk.PubKeyAlgo, test.pubKeyAlgo)
+ }
+ if pk.CreationTime != test.creationTime {
+ t.Errorf("#%d: bad creation time got:%x want:%x", i, pk.CreationTime, test.creationTime)
+ }
+ expectedFingerprint, _ := hex.DecodeString(test.hexFingerprint)
+ if !bytes.Equal(expectedFingerprint, pk.Fingerprint[:]) {
+ t.Errorf("#%d: bad fingerprint got:%x want:%x", i, pk.Fingerprint[:], expectedFingerprint)
+ }
+ if pk.KeyId != test.keyId {
+ t.Errorf("#%d: bad keyid got:%x want:%x", i, pk.KeyId, test.keyId)
+ }
+ if g, e := pk.KeyIdString(), test.keyIdString; g != e {
+ t.Errorf("#%d: bad KeyIdString got:%q want:%q", i, g, e)
+ }
+ if g, e := pk.KeyIdShortString(), test.keyIdShort; g != e {
+ t.Errorf("#%d: bad KeyIdShortString got:%q want:%q", i, g, e)
+ }
+ }
+}
+
+func TestPublicKeySerialize(t *testing.T) {
+ for i, test := range pubKeyTests {
+ packet, err := Read(readerFromHex(test.hexData))
+ if err != nil {
+ t.Errorf("#%d: Read error: %s", i, err)
+ continue
+ }
+ pk, ok := packet.(*PublicKey)
+ if !ok {
+ t.Errorf("#%d: failed to parse, got: %#v", i, packet)
+ continue
+ }
+ serializeBuf := bytes.NewBuffer(nil)
+ err = pk.Serialize(serializeBuf)
+ if err != nil {
+ t.Errorf("#%d: failed to serialize: %s", i, err)
+ continue
+ }
+
+ packet, err = Read(serializeBuf)
+ if err != nil {
+ t.Errorf("#%d: Read error (from serialized data): %s", i, err)
+ continue
+ }
+ pk, ok = packet.(*PublicKey)
+ if !ok {
+ t.Errorf("#%d: failed to parse serialized data, got: %#v", i, packet)
+ continue
+ }
+ }
+}
+
+const rsaFingerprintHex = "5fb74b1d03b1e3cb31bc2f8aa34d7e18c20c31bb"
+
+const rsaPkDataHex = "988d044d3c5c10010400b1d13382944bd5aba23a4312968b5095d14f947f600eb478e14a6fcb16b0e0cac764884909c020bc495cfcc39a935387c661507bdb236a0612fb582cac3af9b29cc2c8c70090616c41b662f4da4c1201e195472eb7f4ae1ccbcbf9940fe21d985e379a5563dde5b9a23d35f1cfaa5790da3b79db26f23695107bfaca8e7b5bcd0011010001"
+
+const dsaFingerprintHex = "eece4c094db002103714c63c8e8fbe54062f19ed"
+
+const dsaPkDataHex = "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"
diff --git a/src/pkg/crypto/openpgp/packet/reader.go b/src/pkg/crypto/openpgp/packet/reader.go
new file mode 100644
index 000000000..5febc3bc8
--- /dev/null
+++ b/src/pkg/crypto/openpgp/packet/reader.go
@@ -0,0 +1,63 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package packet
+
+import (
+ "crypto/openpgp/error"
+ "io"
+ "os"
+)
+
+// Reader reads packets from an io.Reader and allows packets to be 'unread' so
+// that they result from the next call to Next.
+type Reader struct {
+ q []Packet
+ readers []io.Reader
+}
+
+// Next returns the most recently unread Packet, or reads another packet from
+// the top-most io.Reader. Unknown packet types are skipped.
+func (r *Reader) Next() (p Packet, err os.Error) {
+ if len(r.q) > 0 {
+ p = r.q[len(r.q)-1]
+ r.q = r.q[:len(r.q)-1]
+ return
+ }
+
+ for len(r.readers) > 0 {
+ p, err = Read(r.readers[len(r.readers)-1])
+ if err == nil {
+ return
+ }
+ if err == os.EOF {
+ r.readers = r.readers[:len(r.readers)-1]
+ continue
+ }
+ if _, ok := err.(error.UnknownPacketTypeError); !ok {
+ return nil, err
+ }
+ }
+
+ return nil, os.EOF
+}
+
+// Push causes the Reader to start reading from a new io.Reader. When an EOF
+// error is seen from the new io.Reader, it is popped and the Reader continues
+// to read from the next most recent io.Reader.
+func (r *Reader) Push(reader io.Reader) {
+ r.readers = append(r.readers, reader)
+}
+
+// Unread causes the given Packet to be returned from the next call to Next.
+func (r *Reader) Unread(p Packet) {
+ r.q = append(r.q, p)
+}
+
+func NewReader(r io.Reader) *Reader {
+ return &Reader{
+ q: nil,
+ readers: []io.Reader{r},
+ }
+}
diff --git a/src/pkg/crypto/openpgp/packet/signature.go b/src/pkg/crypto/openpgp/packet/signature.go
new file mode 100644
index 000000000..7577e2875
--- /dev/null
+++ b/src/pkg/crypto/openpgp/packet/signature.go
@@ -0,0 +1,558 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package packet
+
+import (
+ "crypto"
+ "crypto/dsa"
+ "crypto/openpgp/error"
+ "crypto/openpgp/s2k"
+ "crypto/rand"
+ "crypto/rsa"
+ "encoding/binary"
+ "hash"
+ "io"
+ "os"
+ "strconv"
+)
+
+// Signature represents a signature. See RFC 4880, section 5.2.
+type Signature struct {
+ SigType SignatureType
+ PubKeyAlgo PublicKeyAlgorithm
+ Hash crypto.Hash
+
+ // HashSuffix is extra data that is hashed in after the signed data.
+ HashSuffix []byte
+ // HashTag contains the first two bytes of the hash for fast rejection
+ // of bad signed data.
+ HashTag [2]byte
+ CreationTime uint32 // Unix epoch time
+
+ RSASignature parsedMPI
+ DSASigR, DSASigS parsedMPI
+
+ // rawSubpackets contains the unparsed subpackets, in order.
+ rawSubpackets []outputSubpacket
+
+ // The following are optional so are nil when not included in the
+ // signature.
+
+ SigLifetimeSecs, KeyLifetimeSecs *uint32
+ PreferredSymmetric, PreferredHash, PreferredCompression []uint8
+ IssuerKeyId *uint64
+ IsPrimaryId *bool
+
+ // FlagsValid is set if any flags were given. See RFC 4880, section
+ // 5.2.3.21 for details.
+ FlagsValid bool
+ FlagCertify, FlagSign, FlagEncryptCommunications, FlagEncryptStorage bool
+
+ outSubpackets []outputSubpacket
+}
+
+func (sig *Signature) parse(r io.Reader) (err os.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 = error.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:
+ default:
+ err = error.UnsupportedError("public key algorithm " + strconv.Itoa(int(sig.PubKeyAlgo)))
+ return
+ }
+
+ var ok bool
+ sig.Hash, ok = s2k.HashIdToHash(buf[2])
+ if !ok {
+ return error.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)
+ }
+ default:
+ panic("unreachable")
+ }
+ return
+}
+
+// parseSignatureSubpackets parses subpackets of the main signature packet. See
+// RFC 4880, section 5.2.3.1.
+func parseSignatureSubpackets(sig *Signature, subpackets []byte, isHashed bool) (err os.Error) {
+ for len(subpackets) > 0 {
+ subpackets, err = parseSignatureSubpacket(sig, subpackets, isHashed)
+ if err != nil {
+ return
+ }
+ }
+
+ if sig.CreationTime == 0 {
+ err = error.StructuralError("no creation time in signature")
+ }
+
+ return
+}
+
+type signatureSubpacketType uint8
+
+const (
+ creationTimeSubpacket signatureSubpacketType = 2
+ signatureExpirationSubpacket signatureSubpacketType = 3
+ keyExpirySubpacket signatureSubpacketType = 9
+ prefSymmetricAlgosSubpacket signatureSubpacketType = 11
+ issuerSubpacket signatureSubpacketType = 16
+ prefHashAlgosSubpacket signatureSubpacketType = 21
+ prefCompressionSubpacket signatureSubpacketType = 22
+ primaryUserIdSubpacket signatureSubpacketType = 25
+ keyFlagsSubpacket signatureSubpacketType = 27
+)
+
+// parseSignatureSubpacket parses a single subpacket. len(subpacket) is >= 1.
+func parseSignatureSubpacket(sig *Signature, subpacket []byte, isHashed bool) (rest []byte, err os.Error) {
+ // RFC 4880, section 5.2.3.1
+ var (
+ length uint32
+ packetType signatureSubpacketType
+ isCritical bool
+ )
+ switch {
+ case subpacket[0] < 192:
+ length = uint32(subpacket[0])
+ subpacket = subpacket[1:]
+ case subpacket[0] < 255:
+ if len(subpacket) < 2 {
+ goto Truncated
+ }
+ length = uint32(subpacket[0]-192)<<8 + uint32(subpacket[1]) + 192
+ subpacket = subpacket[2:]
+ default:
+ if len(subpacket) < 5 {
+ goto Truncated
+ }
+ length = uint32(subpacket[1])<<24 |
+ uint32(subpacket[2])<<16 |
+ uint32(subpacket[3])<<8 |
+ uint32(subpacket[4])
+ subpacket = subpacket[5:]
+ }
+ if length > uint32(len(subpacket)) {
+ goto Truncated
+ }
+ rest = subpacket[length:]
+ subpacket = subpacket[:length]
+ if len(subpacket) == 0 {
+ err = error.StructuralError("zero length signature subpacket")
+ return
+ }
+ packetType = signatureSubpacketType(subpacket[0] & 0x7f)
+ isCritical = subpacket[0]&0x80 == 0x80
+ subpacket = subpacket[1:]
+ sig.rawSubpackets = append(sig.rawSubpackets, outputSubpacket{isHashed, packetType, isCritical, subpacket})
+ switch packetType {
+ case creationTimeSubpacket:
+ if !isHashed {
+ err = error.StructuralError("signature creation time in non-hashed area")
+ return
+ }
+ if len(subpacket) != 4 {
+ err = error.StructuralError("signature creation time not four bytes")
+ return
+ }
+ sig.CreationTime = binary.BigEndian.Uint32(subpacket)
+ case signatureExpirationSubpacket:
+ // Signature expiration time, section 5.2.3.10
+ if !isHashed {
+ return
+ }
+ if len(subpacket) != 4 {
+ err = error.StructuralError("expiration subpacket with bad length")
+ return
+ }
+ sig.SigLifetimeSecs = new(uint32)
+ *sig.SigLifetimeSecs = binary.BigEndian.Uint32(subpacket)
+ case keyExpirySubpacket:
+ // Key expiration time, section 5.2.3.6
+ if !isHashed {
+ return
+ }
+ if len(subpacket) != 4 {
+ err = error.StructuralError("key expiration subpacket with bad length")
+ return
+ }
+ sig.KeyLifetimeSecs = new(uint32)
+ *sig.KeyLifetimeSecs = binary.BigEndian.Uint32(subpacket)
+ case prefSymmetricAlgosSubpacket:
+ // Preferred symmetric algorithms, section 5.2.3.7
+ if !isHashed {
+ return
+ }
+ sig.PreferredSymmetric = make([]byte, len(subpacket))
+ copy(sig.PreferredSymmetric, subpacket)
+ case issuerSubpacket:
+ // Issuer, section 5.2.3.5
+ if len(subpacket) != 8 {
+ err = error.StructuralError("issuer subpacket with bad length")
+ return
+ }
+ sig.IssuerKeyId = new(uint64)
+ *sig.IssuerKeyId = binary.BigEndian.Uint64(subpacket)
+ case prefHashAlgosSubpacket:
+ // Preferred hash algorithms, section 5.2.3.8
+ if !isHashed {
+ return
+ }
+ sig.PreferredHash = make([]byte, len(subpacket))
+ copy(sig.PreferredHash, subpacket)
+ case prefCompressionSubpacket:
+ // Preferred compression algorithms, section 5.2.3.9
+ if !isHashed {
+ return
+ }
+ sig.PreferredCompression = make([]byte, len(subpacket))
+ copy(sig.PreferredCompression, subpacket)
+ case primaryUserIdSubpacket:
+ // Primary User ID, section 5.2.3.19
+ if !isHashed {
+ return
+ }
+ if len(subpacket) != 1 {
+ err = error.StructuralError("primary user id subpacket with bad length")
+ return
+ }
+ sig.IsPrimaryId = new(bool)
+ if subpacket[0] > 0 {
+ *sig.IsPrimaryId = true
+ }
+ case keyFlagsSubpacket:
+ // Key flags, section 5.2.3.21
+ if !isHashed {
+ return
+ }
+ if len(subpacket) == 0 {
+ err = error.StructuralError("empty key flags subpacket")
+ return
+ }
+ sig.FlagsValid = true
+ if subpacket[0]&1 != 0 {
+ sig.FlagCertify = true
+ }
+ if subpacket[0]&2 != 0 {
+ sig.FlagSign = true
+ }
+ if subpacket[0]&4 != 0 {
+ sig.FlagEncryptCommunications = true
+ }
+ if subpacket[0]&8 != 0 {
+ sig.FlagEncryptStorage = true
+ }
+
+ default:
+ if isCritical {
+ err = error.UnsupportedError("unknown critical signature subpacket type " + strconv.Itoa(int(packetType)))
+ return
+ }
+ }
+ return
+
+Truncated:
+ err = error.StructuralError("signature subpacket truncated")
+ return
+}
+
+// subpacketLengthLength returns the length, in bytes, of an encoded length value.
+func subpacketLengthLength(length int) int {
+ if length < 192 {
+ return 1
+ }
+ if length < 16320 {
+ return 2
+ }
+ return 5
+}
+
+// serializeSubpacketLength marshals the given length into to.
+func serializeSubpacketLength(to []byte, length int) int {
+ if length < 192 {
+ to[0] = byte(length)
+ return 1
+ }
+ if length < 16320 {
+ length -= 192
+ to[0] = byte(length >> 8)
+ to[1] = byte(length)
+ return 2
+ }
+ to[0] = 255
+ to[1] = byte(length >> 24)
+ to[2] = byte(length >> 16)
+ to[3] = byte(length >> 8)
+ to[4] = byte(length)
+ return 5
+}
+
+// subpacketsLength returns the serialized length, in bytes, of the given
+// subpackets.
+func subpacketsLength(subpackets []outputSubpacket, hashed bool) (length int) {
+ for _, subpacket := range subpackets {
+ if subpacket.hashed == hashed {
+ length += subpacketLengthLength(len(subpacket.contents) + 1)
+ length += 1 // type byte
+ length += len(subpacket.contents)
+ }
+ }
+ return
+}
+
+// serializeSubpackets marshals the given subpackets into to.
+func serializeSubpackets(to []byte, subpackets []outputSubpacket, hashed bool) {
+ for _, subpacket := range subpackets {
+ if subpacket.hashed == hashed {
+ n := serializeSubpacketLength(to, len(subpacket.contents)+1)
+ to[n] = byte(subpacket.subpacketType)
+ to = to[1+n:]
+ n = copy(to, subpacket.contents)
+ to = to[n:]
+ }
+ }
+ return
+}
+
+// buildHashSuffix constructs the HashSuffix member of sig in preparation for signing.
+func (sig *Signature) buildHashSuffix() (err os.Error) {
+ hashedSubpacketsLen := subpacketsLength(sig.outSubpackets, true)
+
+ var ok bool
+ l := 6 + hashedSubpacketsLen
+ sig.HashSuffix = make([]byte, l+6)
+ sig.HashSuffix[0] = 4
+ sig.HashSuffix[1] = uint8(sig.SigType)
+ sig.HashSuffix[2] = uint8(sig.PubKeyAlgo)
+ sig.HashSuffix[3], ok = s2k.HashToHashId(sig.Hash)
+ if !ok {
+ sig.HashSuffix = nil
+ return error.InvalidArgumentError("hash cannot be represented in OpenPGP: " + strconv.Itoa(int(sig.Hash)))
+ }
+ sig.HashSuffix[4] = byte(hashedSubpacketsLen >> 8)
+ sig.HashSuffix[5] = byte(hashedSubpacketsLen)
+ serializeSubpackets(sig.HashSuffix[6:l], sig.outSubpackets, true)
+ trailer := sig.HashSuffix[l:]
+ trailer[0] = 4
+ trailer[1] = 0xff
+ trailer[2] = byte(l >> 24)
+ trailer[3] = byte(l >> 16)
+ trailer[4] = byte(l >> 8)
+ trailer[5] = byte(l)
+ return
+}
+
+func (sig *Signature) signPrepareHash(h hash.Hash) (digest []byte, err os.Error) {
+ err = sig.buildHashSuffix()
+ if err != nil {
+ return
+ }
+
+ h.Write(sig.HashSuffix)
+ digest = h.Sum()
+ copy(sig.HashTag[:], digest)
+ return
+}
+
+// Sign signs a message with a private key. The hash, h, must contain
+// the hash of the message to be signed and will be mutated by this function.
+// On success, the signature is stored in sig. Call Serialize to write it out.
+func (sig *Signature) Sign(h hash.Hash, priv *PrivateKey) (err os.Error) {
+ sig.outSubpackets = sig.buildSubpackets()
+ digest, err := sig.signPrepareHash(h)
+ if err != nil {
+ return
+ }
+
+ switch priv.PubKeyAlgo {
+ case PubKeyAlgoRSA, PubKeyAlgoRSASignOnly:
+ sig.RSASignature.bytes, err = rsa.SignPKCS1v15(rand.Reader, priv.PrivateKey.(*rsa.PrivateKey), sig.Hash, digest)
+ sig.RSASignature.bitLength = uint16(8 * len(sig.RSASignature.bytes))
+ case PubKeyAlgoDSA:
+ r, s, err := dsa.Sign(rand.Reader, priv.PrivateKey.(*dsa.PrivateKey), digest)
+ if err == nil {
+ sig.DSASigR.bytes = r.Bytes()
+ sig.DSASigR.bitLength = uint16(8 * len(sig.DSASigR.bytes))
+ sig.DSASigS.bytes = s.Bytes()
+ sig.DSASigS.bitLength = uint16(8 * len(sig.DSASigS.bytes))
+ }
+ default:
+ err = error.UnsupportedError("public key algorithm: " + strconv.Itoa(int(sig.PubKeyAlgo)))
+ }
+
+ return
+}
+
+// SignUserId computes a signature from priv, asserting that pub is a valid
+// key for the identity id. On success, the signature is stored in sig. Call
+// Serialize to write it out.
+func (sig *Signature) SignUserId(id string, pub *PublicKey, priv *PrivateKey) os.Error {
+ h, err := userIdSignatureHash(id, pub, sig)
+ if err != nil {
+ return nil
+ }
+ return sig.Sign(h, priv)
+}
+
+// SignKey computes a signature from priv, asserting that pub is a subkey. On
+// success, the signature is stored in sig. Call Serialize to write it out.
+func (sig *Signature) SignKey(pub *PublicKey, priv *PrivateKey) os.Error {
+ h, err := keySignatureHash(&priv.PublicKey, pub, sig)
+ if err != nil {
+ return err
+ }
+ return sig.Sign(h, priv)
+}
+
+// Serialize marshals sig to w. SignRSA or SignDSA must have been called first.
+func (sig *Signature) Serialize(w io.Writer) (err os.Error) {
+ if len(sig.outSubpackets) == 0 {
+ sig.outSubpackets = sig.rawSubpackets
+ }
+ if sig.RSASignature.bytes == nil && sig.DSASigR.bytes == nil {
+ return error.InvalidArgumentError("Signature: need to call SignRSA or SignDSA before Serialize")
+ }
+
+ sigLength := 0
+ switch sig.PubKeyAlgo {
+ case PubKeyAlgoRSA, PubKeyAlgoRSASignOnly:
+ sigLength = 2 + len(sig.RSASignature.bytes)
+ case PubKeyAlgoDSA:
+ sigLength = 2 + len(sig.DSASigR.bytes)
+ sigLength += 2 + len(sig.DSASigS.bytes)
+ default:
+ panic("impossible")
+ }
+
+ unhashedSubpacketsLen := subpacketsLength(sig.outSubpackets, false)
+ length := len(sig.HashSuffix) - 6 /* trailer not included */ +
+ 2 /* length of unhashed subpackets */ + unhashedSubpacketsLen +
+ 2 /* hash tag */ + sigLength
+ err = serializeHeader(w, packetTypeSignature, length)
+ if err != nil {
+ return
+ }
+
+ _, err = w.Write(sig.HashSuffix[:len(sig.HashSuffix)-6])
+ if err != nil {
+ return
+ }
+
+ unhashedSubpackets := make([]byte, 2+unhashedSubpacketsLen)
+ unhashedSubpackets[0] = byte(unhashedSubpacketsLen >> 8)
+ unhashedSubpackets[1] = byte(unhashedSubpacketsLen)
+ serializeSubpackets(unhashedSubpackets[2:], sig.outSubpackets, false)
+
+ _, err = w.Write(unhashedSubpackets)
+ if err != nil {
+ return
+ }
+ _, err = w.Write(sig.HashTag[:])
+ if err != nil {
+ return
+ }
+
+ switch sig.PubKeyAlgo {
+ case PubKeyAlgoRSA, PubKeyAlgoRSASignOnly:
+ err = writeMPIs(w, sig.RSASignature)
+ case PubKeyAlgoDSA:
+ err = writeMPIs(w, sig.DSASigR, sig.DSASigS)
+ default:
+ panic("impossible")
+ }
+ return
+}
+
+// outputSubpacket represents a subpacket to be marshaled.
+type outputSubpacket struct {
+ hashed bool // true if this subpacket is in the hashed area.
+ subpacketType signatureSubpacketType
+ isCritical bool
+ contents []byte
+}
+
+func (sig *Signature) buildSubpackets() (subpackets []outputSubpacket) {
+ creationTime := make([]byte, 4)
+ creationTime[0] = byte(sig.CreationTime >> 24)
+ creationTime[1] = byte(sig.CreationTime >> 16)
+ creationTime[2] = byte(sig.CreationTime >> 8)
+ creationTime[3] = byte(sig.CreationTime)
+ subpackets = append(subpackets, outputSubpacket{true, creationTimeSubpacket, false, creationTime})
+
+ if sig.IssuerKeyId != nil {
+ keyId := make([]byte, 8)
+ binary.BigEndian.PutUint64(keyId, *sig.IssuerKeyId)
+ subpackets = append(subpackets, outputSubpacket{true, issuerSubpacket, false, keyId})
+ }
+
+ return
+}
diff --git a/src/pkg/crypto/openpgp/packet/signature_test.go b/src/pkg/crypto/openpgp/packet/signature_test.go
new file mode 100644
index 000000000..c1bbde8b0
--- /dev/null
+++ b/src/pkg/crypto/openpgp/packet/signature_test.go
@@ -0,0 +1,42 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package packet
+
+import (
+ "bytes"
+ "crypto"
+ "encoding/hex"
+ "testing"
+)
+
+func TestSignatureRead(t *testing.T) {
+ packet, err := Read(readerFromHex(signatureDataHex))
+ if err != nil {
+ t.Error(err)
+ return
+ }
+ sig, ok := packet.(*Signature)
+ if !ok || sig.SigType != SigTypeBinary || sig.PubKeyAlgo != PubKeyAlgoRSA || sig.Hash != crypto.SHA1 {
+ t.Errorf("failed to parse, got: %#v", packet)
+ }
+}
+
+func TestSignatureReserialize(t *testing.T) {
+ packet, _ := Read(readerFromHex(signatureDataHex))
+ sig := packet.(*Signature)
+ out := new(bytes.Buffer)
+ err := sig.Serialize(out)
+ if err != nil {
+ t.Errorf("error reserializing: %s", err)
+ return
+ }
+
+ expected, _ := hex.DecodeString(signatureDataHex)
+ if !bytes.Equal(expected, out.Bytes()) {
+ t.Errorf("output doesn't match input (got vs expected):\n%s\n%s", hex.Dump(out.Bytes()), hex.Dump(expected))
+ }
+}
+
+const signatureDataHex = "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"
diff --git a/src/pkg/crypto/openpgp/packet/symmetric_key_encrypted.go b/src/pkg/crypto/openpgp/packet/symmetric_key_encrypted.go
new file mode 100644
index 000000000..ad4f1d621
--- /dev/null
+++ b/src/pkg/crypto/openpgp/packet/symmetric_key_encrypted.go
@@ -0,0 +1,162 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package packet
+
+import (
+ "bytes"
+ "crypto/cipher"
+ "crypto/openpgp/error"
+ "crypto/openpgp/s2k"
+ "io"
+ "os"
+ "strconv"
+)
+
+// This is the largest session key that we'll support. Since no 512-bit cipher
+// has even been seriously used, this is comfortably large.
+const maxSessionKeySizeInBytes = 64
+
+// SymmetricKeyEncrypted represents a passphrase protected session key. See RFC
+// 4880, section 5.3.
+type SymmetricKeyEncrypted struct {
+ CipherFunc CipherFunction
+ Encrypted bool
+ Key []byte // Empty unless Encrypted is false.
+ s2k func(out, in []byte)
+ encryptedKey []byte
+}
+
+const symmetricKeyEncryptedVersion = 4
+
+func (ske *SymmetricKeyEncrypted) parse(r io.Reader) (err os.Error) {
+ // RFC 4880, section 5.3.
+ var buf [2]byte
+ _, err = readFull(r, buf[:])
+ if err != nil {
+ return
+ }
+ if buf[0] != symmetricKeyEncryptedVersion {
+ return error.UnsupportedError("SymmetricKeyEncrypted version")
+ }
+ ske.CipherFunc = CipherFunction(buf[1])
+
+ if ske.CipherFunc.KeySize() == 0 {
+ return error.UnsupportedError("unknown cipher: " + strconv.Itoa(int(buf[1])))
+ }
+
+ ske.s2k, err = s2k.Parse(r)
+ if err != nil {
+ return
+ }
+
+ encryptedKey := make([]byte, maxSessionKeySizeInBytes)
+ // The session key may follow. We just have to try and read to find
+ // out. If it exists then we limit it to maxSessionKeySizeInBytes.
+ n, err := readFull(r, encryptedKey)
+ if err != nil && err != io.ErrUnexpectedEOF {
+ return
+ }
+ err = nil
+ if n != 0 {
+ if n == maxSessionKeySizeInBytes {
+ return error.UnsupportedError("oversized encrypted session key")
+ }
+ ske.encryptedKey = encryptedKey[:n]
+ }
+
+ ske.Encrypted = true
+
+ return
+}
+
+// Decrypt attempts to decrypt an encrypted session key. If it returns nil,
+// ske.Key will contain the session key.
+func (ske *SymmetricKeyEncrypted) Decrypt(passphrase []byte) os.Error {
+ if !ske.Encrypted {
+ return nil
+ }
+
+ key := make([]byte, ske.CipherFunc.KeySize())
+ ske.s2k(key, passphrase)
+
+ if len(ske.encryptedKey) == 0 {
+ ske.Key = key
+ } else {
+ // the IV is all zeros
+ iv := make([]byte, ske.CipherFunc.blockSize())
+ c := cipher.NewCFBDecrypter(ske.CipherFunc.new(key), iv)
+ c.XORKeyStream(ske.encryptedKey, ske.encryptedKey)
+ ske.CipherFunc = CipherFunction(ske.encryptedKey[0])
+ if ske.CipherFunc.blockSize() == 0 {
+ return error.UnsupportedError("unknown cipher: " + strconv.Itoa(int(ske.CipherFunc)))
+ }
+ ske.CipherFunc = CipherFunction(ske.encryptedKey[0])
+ ske.Key = ske.encryptedKey[1:]
+ if len(ske.Key)%ske.CipherFunc.blockSize() != 0 {
+ ske.Key = nil
+ return error.StructuralError("length of decrypted key not a multiple of block size")
+ }
+ }
+
+ ske.Encrypted = false
+ return nil
+}
+
+// SerializeSymmetricKeyEncrypted serializes a symmetric key packet to w. The
+// packet contains a random session key, encrypted by a key derived from the
+// given passphrase. The session key is returned and must be passed to
+// SerializeSymmetricallyEncrypted.
+func SerializeSymmetricKeyEncrypted(w io.Writer, rand io.Reader, passphrase []byte, cipherFunc CipherFunction) (key []byte, err os.Error) {
+ keySize := cipherFunc.KeySize()
+ if keySize == 0 {
+ return nil, error.UnsupportedError("unknown cipher: " + strconv.Itoa(int(cipherFunc)))
+ }
+
+ s2kBuf := new(bytes.Buffer)
+ keyEncryptingKey := make([]byte, keySize)
+ // s2k.Serialize salts and stretches the passphrase, and writes the
+ // resulting key to keyEncryptingKey and the s2k descriptor to s2kBuf.
+ err = s2k.Serialize(s2kBuf, keyEncryptingKey, rand, passphrase)
+ if err != nil {
+ return
+ }
+ s2kBytes := s2kBuf.Bytes()
+
+ packetLength := 2 /* header */ + len(s2kBytes) + 1 /* cipher type */ + keySize
+ err = serializeHeader(w, packetTypeSymmetricKeyEncrypted, packetLength)
+ if err != nil {
+ return
+ }
+
+ var buf [2]byte
+ buf[0] = symmetricKeyEncryptedVersion
+ buf[1] = byte(cipherFunc)
+ _, err = w.Write(buf[:])
+ if err != nil {
+ return
+ }
+ _, err = w.Write(s2kBytes)
+ if err != nil {
+ return
+ }
+
+ sessionKey := make([]byte, keySize)
+ _, err = io.ReadFull(rand, sessionKey)
+ if err != nil {
+ return
+ }
+ iv := make([]byte, cipherFunc.blockSize())
+ c := cipher.NewCFBEncrypter(cipherFunc.new(keyEncryptingKey), iv)
+ encryptedCipherAndKey := make([]byte, keySize+1)
+ c.XORKeyStream(encryptedCipherAndKey, buf[1:])
+ c.XORKeyStream(encryptedCipherAndKey[1:], sessionKey)
+ _, err = w.Write(encryptedCipherAndKey)
+ if err != nil {
+ return
+ }
+
+ key = sessionKey
+ return
+}
diff --git a/src/pkg/crypto/openpgp/packet/symmetric_key_encrypted_test.go b/src/pkg/crypto/openpgp/packet/symmetric_key_encrypted_test.go
new file mode 100644
index 000000000..823ec400d
--- /dev/null
+++ b/src/pkg/crypto/openpgp/packet/symmetric_key_encrypted_test.go
@@ -0,0 +1,101 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package packet
+
+import (
+ "bytes"
+ "crypto/rand"
+ "encoding/hex"
+ "io/ioutil"
+ "os"
+ "testing"
+)
+
+func TestSymmetricKeyEncrypted(t *testing.T) {
+ buf := readerFromHex(symmetricallyEncryptedHex)
+ packet, err := Read(buf)
+ if err != nil {
+ t.Errorf("failed to read SymmetricKeyEncrypted: %s", err)
+ return
+ }
+ ske, ok := packet.(*SymmetricKeyEncrypted)
+ if !ok {
+ t.Error("didn't find SymmetricKeyEncrypted packet")
+ return
+ }
+ err = ske.Decrypt([]byte("password"))
+ if err != nil {
+ t.Error(err)
+ return
+ }
+
+ packet, err = Read(buf)
+ if err != nil {
+ t.Errorf("failed to read SymmetricallyEncrypted: %s", err)
+ return
+ }
+ se, ok := packet.(*SymmetricallyEncrypted)
+ if !ok {
+ t.Error("didn't find SymmetricallyEncrypted packet")
+ return
+ }
+ r, err := se.Decrypt(ske.CipherFunc, ske.Key)
+ if err != nil {
+ t.Error(err)
+ return
+ }
+
+ contents, err := ioutil.ReadAll(r)
+ if err != nil && err != os.EOF {
+ t.Error(err)
+ return
+ }
+
+ expectedContents, _ := hex.DecodeString(symmetricallyEncryptedContentsHex)
+ if !bytes.Equal(expectedContents, contents) {
+ t.Errorf("bad contents got:%x want:%x", contents, expectedContents)
+ }
+}
+
+const symmetricallyEncryptedHex = "8c0d04030302371a0b38d884f02060c91cf97c9973b8e58e028e9501708ccfe618fb92afef7fa2d80ddadd93cf"
+const symmetricallyEncryptedContentsHex = "cb1062004d14c4df636f6e74656e74732e0a"
+
+func TestSerializeSymmetricKeyEncrypted(t *testing.T) {
+ buf := bytes.NewBuffer(nil)
+ passphrase := []byte("testing")
+ cipherFunc := CipherAES128
+
+ key, err := SerializeSymmetricKeyEncrypted(buf, rand.Reader, passphrase, cipherFunc)
+ if err != nil {
+ t.Errorf("failed to serialize: %s", err)
+ return
+ }
+
+ p, err := Read(buf)
+ if err != nil {
+ t.Errorf("failed to reparse: %s", err)
+ return
+ }
+ ske, ok := p.(*SymmetricKeyEncrypted)
+ if !ok {
+ t.Errorf("parsed a different packet type: %#v", p)
+ return
+ }
+
+ if !ske.Encrypted {
+ t.Errorf("SKE not encrypted but should be")
+ }
+ if ske.CipherFunc != cipherFunc {
+ t.Errorf("SKE cipher function is %d (expected %d)", ske.CipherFunc, cipherFunc)
+ }
+ err = ske.Decrypt(passphrase)
+ if err != nil {
+ t.Errorf("failed to decrypt reparsed SKE: %s", err)
+ return
+ }
+ if !bytes.Equal(key, ske.Key) {
+ t.Errorf("keys don't match after Decrpyt: %x (original) vs %x (parsed)", key, ske.Key)
+ }
+}
diff --git a/src/pkg/crypto/openpgp/packet/symmetrically_encrypted.go b/src/pkg/crypto/openpgp/packet/symmetrically_encrypted.go
new file mode 100644
index 000000000..e33c9f3a0
--- /dev/null
+++ b/src/pkg/crypto/openpgp/packet/symmetrically_encrypted.go
@@ -0,0 +1,291 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package packet
+
+import (
+ "crypto/cipher"
+ "crypto/openpgp/error"
+ "crypto/rand"
+ "crypto/sha1"
+ "crypto/subtle"
+ "hash"
+ "io"
+ "os"
+ "strconv"
+)
+
+// SymmetricallyEncrypted represents a symmetrically encrypted byte string. The
+// encrypted contents will consist of more OpenPGP packets. See RFC 4880,
+// sections 5.7 and 5.13.
+type SymmetricallyEncrypted struct {
+ MDC bool // true iff this is a type 18 packet and thus has an embedded MAC.
+ contents io.Reader
+ prefix []byte
+}
+
+const symmetricallyEncryptedVersion = 1
+
+func (se *SymmetricallyEncrypted) parse(r io.Reader) os.Error {
+ if se.MDC {
+ // See RFC 4880, section 5.13.
+ var buf [1]byte
+ _, err := readFull(r, buf[:])
+ if err != nil {
+ return err
+ }
+ if buf[0] != symmetricallyEncryptedVersion {
+ return error.UnsupportedError("unknown SymmetricallyEncrypted version")
+ }
+ }
+ se.contents = r
+ return nil
+}
+
+// Decrypt returns a ReadCloser, from which the decrypted contents of the
+// packet can be read. An incorrect key can, with high probability, be detected
+// immediately and this will result in a KeyIncorrect error being returned.
+func (se *SymmetricallyEncrypted) Decrypt(c CipherFunction, key []byte) (io.ReadCloser, os.Error) {
+ keySize := c.KeySize()
+ if keySize == 0 {
+ return nil, error.UnsupportedError("unknown cipher: " + strconv.Itoa(int(c)))
+ }
+ if len(key) != keySize {
+ return nil, error.InvalidArgumentError("SymmetricallyEncrypted: incorrect key length")
+ }
+
+ if se.prefix == nil {
+ se.prefix = make([]byte, c.blockSize()+2)
+ _, err := readFull(se.contents, se.prefix)
+ if err != nil {
+ return nil, err
+ }
+ } else if len(se.prefix) != c.blockSize()+2 {
+ return nil, error.InvalidArgumentError("can't try ciphers with different block lengths")
+ }
+
+ ocfbResync := cipher.OCFBResync
+ if se.MDC {
+ // MDC packets use a different form of OCFB mode.
+ ocfbResync = cipher.OCFBNoResync
+ }
+
+ s := cipher.NewOCFBDecrypter(c.new(key), se.prefix, ocfbResync)
+ if s == nil {
+ return nil, error.KeyIncorrectError
+ }
+
+ plaintext := cipher.StreamReader{S: s, R: se.contents}
+
+ if se.MDC {
+ // MDC packets have an embedded hash that we need to check.
+ h := sha1.New()
+ h.Write(se.prefix)
+ return &seMDCReader{in: plaintext, h: h}, nil
+ }
+
+ // Otherwise, we just need to wrap plaintext so that it's a valid ReadCloser.
+ return seReader{plaintext}, nil
+}
+
+// seReader wraps an io.Reader with a no-op Close method.
+type seReader struct {
+ in io.Reader
+}
+
+func (ser seReader) Read(buf []byte) (int, os.Error) {
+ return ser.in.Read(buf)
+}
+
+func (ser seReader) Close() os.Error {
+ return nil
+}
+
+const mdcTrailerSize = 1 /* tag byte */ + 1 /* length byte */ + sha1.Size
+
+// An seMDCReader wraps an io.Reader, maintains a running hash and keeps hold
+// of the most recent 22 bytes (mdcTrailerSize). Upon EOF, those bytes form an
+// MDC packet containing a hash of the previous contents which is checked
+// against the running hash. See RFC 4880, section 5.13.
+type seMDCReader struct {
+ in io.Reader
+ h hash.Hash
+ trailer [mdcTrailerSize]byte
+ scratch [mdcTrailerSize]byte
+ trailerUsed int
+ error bool
+ eof bool
+}
+
+func (ser *seMDCReader) Read(buf []byte) (n int, err os.Error) {
+ if ser.error {
+ err = io.ErrUnexpectedEOF
+ return
+ }
+ if ser.eof {
+ err = os.EOF
+ return
+ }
+
+ // If we haven't yet filled the trailer buffer then we must do that
+ // first.
+ for ser.trailerUsed < mdcTrailerSize {
+ n, err = ser.in.Read(ser.trailer[ser.trailerUsed:])
+ ser.trailerUsed += n
+ if err == os.EOF {
+ if ser.trailerUsed != mdcTrailerSize {
+ n = 0
+ err = io.ErrUnexpectedEOF
+ ser.error = true
+ return
+ }
+ ser.eof = true
+ n = 0
+ return
+ }
+
+ if err != nil {
+ n = 0
+ return
+ }
+ }
+
+ // If it's a short read then we read into a temporary buffer and shift
+ // the data into the caller's buffer.
+ if len(buf) <= mdcTrailerSize {
+ n, err = readFull(ser.in, ser.scratch[:len(buf)])
+ copy(buf, ser.trailer[:n])
+ ser.h.Write(buf[:n])
+ copy(ser.trailer[:], ser.trailer[n:])
+ copy(ser.trailer[mdcTrailerSize-n:], ser.scratch[:])
+ if n < len(buf) {
+ ser.eof = true
+ err = os.EOF
+ }
+ return
+ }
+
+ n, err = ser.in.Read(buf[mdcTrailerSize:])
+ copy(buf, ser.trailer[:])
+ ser.h.Write(buf[:n])
+ copy(ser.trailer[:], buf[n:])
+
+ if err == os.EOF {
+ ser.eof = true
+ }
+ return
+}
+
+// This is a new-format packet tag byte for a type 19 (MDC) packet.
+const mdcPacketTagByte = byte(0x80) | 0x40 | 19
+
+func (ser *seMDCReader) Close() os.Error {
+ if ser.error {
+ return error.SignatureError("error during reading")
+ }
+
+ for !ser.eof {
+ // We haven't seen EOF so we need to read to the end
+ var buf [1024]byte
+ _, err := ser.Read(buf[:])
+ if err == os.EOF {
+ break
+ }
+ if err != nil {
+ return error.SignatureError("error during reading")
+ }
+ }
+
+ if ser.trailer[0] != mdcPacketTagByte || ser.trailer[1] != sha1.Size {
+ return error.SignatureError("MDC packet not found")
+ }
+ ser.h.Write(ser.trailer[:2])
+
+ final := ser.h.Sum()
+ if subtle.ConstantTimeCompare(final, ser.trailer[2:]) != 1 {
+ return error.SignatureError("hash mismatch")
+ }
+ return nil
+}
+
+// An seMDCWriter writes through to an io.WriteCloser while maintains a running
+// hash of the data written. On close, it emits an MDC packet containing the
+// running hash.
+type seMDCWriter struct {
+ w io.WriteCloser
+ h hash.Hash
+}
+
+func (w *seMDCWriter) Write(buf []byte) (n int, err os.Error) {
+ w.h.Write(buf)
+ return w.w.Write(buf)
+}
+
+func (w *seMDCWriter) Close() (err os.Error) {
+ var buf [mdcTrailerSize]byte
+
+ buf[0] = mdcPacketTagByte
+ buf[1] = sha1.Size
+ w.h.Write(buf[:2])
+ digest := w.h.Sum()
+ copy(buf[2:], digest)
+
+ _, err = w.w.Write(buf[:])
+ if err != nil {
+ return
+ }
+ return w.w.Close()
+}
+
+// noOpCloser is like an ioutil.NopCloser, but for an io.Writer.
+type noOpCloser struct {
+ w io.Writer
+}
+
+func (c noOpCloser) Write(data []byte) (n int, err os.Error) {
+ return c.w.Write(data)
+}
+
+func (c noOpCloser) Close() os.Error {
+ return nil
+}
+
+// SerializeSymmetricallyEncrypted serializes a symmetrically encrypted packet
+// to w and returns a WriteCloser to which the to-be-encrypted packets can be
+// written.
+func SerializeSymmetricallyEncrypted(w io.Writer, c CipherFunction, key []byte) (contents io.WriteCloser, err os.Error) {
+ if c.KeySize() != len(key) {
+ return nil, error.InvalidArgumentError("SymmetricallyEncrypted.Serialize: bad key length")
+ }
+ writeCloser := noOpCloser{w}
+ ciphertext, err := serializeStreamHeader(writeCloser, packetTypeSymmetricallyEncryptedMDC)
+ if err != nil {
+ return
+ }
+
+ _, err = ciphertext.Write([]byte{symmetricallyEncryptedVersion})
+ if err != nil {
+ return
+ }
+
+ block := c.new(key)
+ blockSize := block.BlockSize()
+ iv := make([]byte, blockSize)
+ _, err = rand.Reader.Read(iv)
+ if err != nil {
+ return
+ }
+ s, prefix := cipher.NewOCFBEncrypter(block, iv, cipher.OCFBNoResync)
+ _, err = ciphertext.Write(prefix)
+ if err != nil {
+ return
+ }
+ plaintext := cipher.StreamWriter{S: s, W: ciphertext}
+
+ h := sha1.New()
+ h.Write(iv)
+ h.Write(iv[blockSize-2:])
+ contents = &seMDCWriter{w: plaintext, h: h}
+ return
+}
diff --git a/src/pkg/crypto/openpgp/packet/symmetrically_encrypted_test.go b/src/pkg/crypto/openpgp/packet/symmetrically_encrypted_test.go
new file mode 100644
index 000000000..1054fc2f9
--- /dev/null
+++ b/src/pkg/crypto/openpgp/packet/symmetrically_encrypted_test.go
@@ -0,0 +1,124 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package packet
+
+import (
+ "bytes"
+ "crypto/openpgp/error"
+ "crypto/sha1"
+ "encoding/hex"
+ "io"
+ "io/ioutil"
+ "os"
+ "testing"
+)
+
+// TestReader wraps a []byte and returns reads of a specific length.
+type testReader struct {
+ data []byte
+ stride int
+}
+
+func (t *testReader) Read(buf []byte) (n int, err os.Error) {
+ n = t.stride
+ if n > len(t.data) {
+ n = len(t.data)
+ }
+ if n > len(buf) {
+ n = len(buf)
+ }
+ copy(buf, t.data)
+ t.data = t.data[n:]
+ if len(t.data) == 0 {
+ err = os.EOF
+ }
+ return
+}
+
+func testMDCReader(t *testing.T) {
+ mdcPlaintext, _ := hex.DecodeString(mdcPlaintextHex)
+
+ for stride := 1; stride < len(mdcPlaintext)/2; stride++ {
+ r := &testReader{data: mdcPlaintext, stride: stride}
+ mdcReader := &seMDCReader{in: r, h: sha1.New()}
+ body, err := ioutil.ReadAll(mdcReader)
+ if err != nil {
+ t.Errorf("stride: %d, error: %s", stride, err)
+ continue
+ }
+ if !bytes.Equal(body, mdcPlaintext[:len(mdcPlaintext)-22]) {
+ t.Errorf("stride: %d: bad contents %x", stride, body)
+ continue
+ }
+
+ err = mdcReader.Close()
+ if err != nil {
+ t.Errorf("stride: %d, error on Close: %s", stride, err)
+ }
+ }
+
+ mdcPlaintext[15] ^= 80
+
+ r := &testReader{data: mdcPlaintext, stride: 2}
+ mdcReader := &seMDCReader{in: r, h: sha1.New()}
+ _, err := ioutil.ReadAll(mdcReader)
+ if err != nil {
+ t.Errorf("corruption test, error: %s", err)
+ return
+ }
+ err = mdcReader.Close()
+ if err == nil {
+ t.Error("corruption: no error")
+ } else if _, ok := err.(*error.SignatureError); !ok {
+ t.Errorf("corruption: expected SignatureError, got: %s", err)
+ }
+}
+
+const mdcPlaintextHex = "a302789c3b2d93c4e0eb9aba22283539b3203335af44a134afb800c849cb4c4de10200aff40b45d31432c80cb384299a0655966d6939dfdeed1dddf980"
+
+func TestSerialize(t *testing.T) {
+ buf := bytes.NewBuffer(nil)
+ c := CipherAES128
+ key := make([]byte, c.KeySize())
+
+ w, err := SerializeSymmetricallyEncrypted(buf, c, key)
+ if err != nil {
+ t.Errorf("error from SerializeSymmetricallyEncrypted: %s", err)
+ return
+ }
+
+ contents := []byte("hello world\n")
+
+ w.Write(contents)
+ w.Close()
+
+ p, err := Read(buf)
+ if err != nil {
+ t.Errorf("error from Read: %s", err)
+ return
+ }
+
+ se, ok := p.(*SymmetricallyEncrypted)
+ if !ok {
+ t.Errorf("didn't read a *SymmetricallyEncrypted")
+ return
+ }
+
+ r, err := se.Decrypt(c, key)
+ if err != nil {
+ t.Errorf("error from Decrypt: %s", err)
+ return
+ }
+
+ contentsCopy := bytes.NewBuffer(nil)
+ _, err = io.Copy(contentsCopy, r)
+ if err != nil {
+ t.Errorf("error from io.Copy: %s", err)
+ return
+ }
+ if !bytes.Equal(contentsCopy.Bytes(), contents) {
+ t.Errorf("contents not equal got: %x want: %x", contentsCopy.Bytes(), contents)
+ }
+}
diff --git a/src/pkg/crypto/openpgp/packet/userid.go b/src/pkg/crypto/openpgp/packet/userid.go
new file mode 100644
index 000000000..0580ba3ed
--- /dev/null
+++ b/src/pkg/crypto/openpgp/packet/userid.go
@@ -0,0 +1,161 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package packet
+
+import (
+ "io"
+ "io/ioutil"
+ "os"
+ "strings"
+)
+
+// UserId contains text that is intended to represent the name and email
+// address of the key holder. See RFC 4880, section 5.11. By convention, this
+// takes the form "Full Name (Comment) <email@example.com>"
+type UserId struct {
+ Id string // By convention, this takes the form "Full Name (Comment) <email@example.com>" which is split out in the fields below.
+
+ Name, Comment, Email string
+}
+
+func hasInvalidCharacters(s string) bool {
+ for _, c := range s {
+ switch c {
+ case '(', ')', '<', '>', 0:
+ return true
+ }
+ }
+ return false
+}
+
+// NewUserId returns a UserId or nil if any of the arguments contain invalid
+// characters. The invalid characters are '\x00', '(', ')', '<' and '>'
+func NewUserId(name, comment, email string) *UserId {
+ // RFC 4880 doesn't deal with the structure of userid strings; the
+ // name, comment and email form is just a convention. However, there's
+ // no convention about escaping the metacharacters and GPG just refuses
+ // to create user ids where, say, the name contains a '('. We mirror
+ // this behaviour.
+
+ if hasInvalidCharacters(name) || hasInvalidCharacters(comment) || hasInvalidCharacters(email) {
+ return nil
+ }
+
+ uid := new(UserId)
+ uid.Name, uid.Comment, uid.Email = name, comment, email
+ uid.Id = name
+ if len(comment) > 0 {
+ if len(uid.Id) > 0 {
+ uid.Id += " "
+ }
+ uid.Id += "("
+ uid.Id += comment
+ uid.Id += ")"
+ }
+ if len(email) > 0 {
+ if len(uid.Id) > 0 {
+ uid.Id += " "
+ }
+ uid.Id += "<"
+ uid.Id += email
+ uid.Id += ">"
+ }
+ return uid
+}
+
+func (uid *UserId) parse(r io.Reader) (err os.Error) {
+ // RFC 4880, section 5.11
+ b, err := ioutil.ReadAll(r)
+ if err != nil {
+ return
+ }
+ uid.Id = string(b)
+ uid.Name, uid.Comment, uid.Email = parseUserId(uid.Id)
+ return
+}
+
+// Serialize marshals uid to w in the form of an OpenPGP packet, including
+// header.
+func (uid *UserId) Serialize(w io.Writer) os.Error {
+ err := serializeHeader(w, packetTypeUserId, len(uid.Id))
+ if err != nil {
+ return err
+ }
+ _, err = w.Write([]byte(uid.Id))
+ return err
+}
+
+// parseUserId extracts the name, comment and email from a user id string that
+// is formatted as "Full Name (Comment) <email@example.com>".
+func parseUserId(id string) (name, comment, email string) {
+ var n, c, e struct {
+ start, end int
+ }
+ var state int
+
+ for offset, rune := range id {
+ switch state {
+ case 0:
+ // Entering name
+ n.start = offset
+ state = 1
+ fallthrough
+ case 1:
+ // In name
+ if rune == '(' {
+ state = 2
+ n.end = offset
+ } else if rune == '<' {
+ state = 5
+ n.end = offset
+ }
+ case 2:
+ // Entering comment
+ c.start = offset
+ state = 3
+ fallthrough
+ case 3:
+ // In comment
+ if rune == ')' {
+ state = 4
+ c.end = offset
+ }
+ case 4:
+ // Between comment and email
+ if rune == '<' {
+ state = 5
+ }
+ case 5:
+ // Entering email
+ e.start = offset
+ state = 6
+ fallthrough
+ case 6:
+ // In email
+ if rune == '>' {
+ state = 7
+ e.end = offset
+ }
+ default:
+ // After email
+ }
+ }
+ switch state {
+ case 1:
+ // ended in the name
+ n.end = len(id)
+ case 3:
+ // ended in comment
+ c.end = len(id)
+ case 6:
+ // ended in email
+ e.end = len(id)
+ }
+
+ name = strings.TrimSpace(id[n.start:n.end])
+ comment = strings.TrimSpace(id[c.start:c.end])
+ email = strings.TrimSpace(id[e.start:e.end])
+ return
+}
diff --git a/src/pkg/crypto/openpgp/packet/userid_test.go b/src/pkg/crypto/openpgp/packet/userid_test.go
new file mode 100644
index 000000000..296819389
--- /dev/null
+++ b/src/pkg/crypto/openpgp/packet/userid_test.go
@@ -0,0 +1,87 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package packet
+
+import (
+ "testing"
+)
+
+var userIdTests = []struct {
+ id string
+ name, comment, email string
+}{
+ {"", "", "", ""},
+ {"John Smith", "John Smith", "", ""},
+ {"John Smith ()", "John Smith", "", ""},
+ {"John Smith () <>", "John Smith", "", ""},
+ {"(comment", "", "comment", ""},
+ {"(comment)", "", "comment", ""},
+ {"<email", "", "", "email"},
+ {"<email> sdfk", "", "", "email"},
+ {" John Smith ( Comment ) asdkflj < email > lksdfj", "John Smith", "Comment", "email"},
+ {" John Smith < email > lksdfj", "John Smith", "", "email"},
+ {"(<foo", "", "<foo", ""},
+ {"René Descartes (العربي)", "René Descartes", "العربي", ""},
+}
+
+func TestParseUserId(t *testing.T) {
+ for i, test := range userIdTests {
+ name, comment, email := parseUserId(test.id)
+ if name != test.name {
+ t.Errorf("%d: name mismatch got:%s want:%s", i, name, test.name)
+ }
+ if comment != test.comment {
+ t.Errorf("%d: comment mismatch got:%s want:%s", i, comment, test.comment)
+ }
+ if email != test.email {
+ t.Errorf("%d: email mismatch got:%s want:%s", i, email, test.email)
+ }
+ }
+}
+
+var newUserIdTests = []struct {
+ name, comment, email, id string
+}{
+ {"foo", "", "", "foo"},
+ {"", "bar", "", "(bar)"},
+ {"", "", "baz", "<baz>"},
+ {"foo", "bar", "", "foo (bar)"},
+ {"foo", "", "baz", "foo <baz>"},
+ {"", "bar", "baz", "(bar) <baz>"},
+ {"foo", "bar", "baz", "foo (bar) <baz>"},
+}
+
+func TestNewUserId(t *testing.T) {
+ for i, test := range newUserIdTests {
+ uid := NewUserId(test.name, test.comment, test.email)
+ if uid == nil {
+ t.Errorf("#%d: returned nil", i)
+ continue
+ }
+ if uid.Id != test.id {
+ t.Errorf("#%d: got '%s', want '%s'", i, uid.Id, test.id)
+ }
+ }
+}
+
+var invalidNewUserIdTests = []struct {
+ name, comment, email string
+}{
+ {"foo(", "", ""},
+ {"foo<", "", ""},
+ {"", "bar)", ""},
+ {"", "bar<", ""},
+ {"", "", "baz>"},
+ {"", "", "baz)"},
+ {"", "", "baz\x00"},
+}
+
+func TestNewUserIdWithInvalidInput(t *testing.T) {
+ for i, test := range invalidNewUserIdTests {
+ if uid := NewUserId(test.name, test.comment, test.email); uid != nil {
+ t.Errorf("#%d: returned non-nil value: %#v", i, uid)
+ }
+ }
+}