diff options
Diffstat (limited to 'src/pkg/crypto/openpgp')
42 files changed, 6774 insertions, 0 deletions
diff --git a/src/pkg/crypto/openpgp/Makefile b/src/pkg/crypto/openpgp/Makefile new file mode 100644 index 000000000..b46ac2bba --- /dev/null +++ b/src/pkg/crypto/openpgp/Makefile @@ -0,0 +1,14 @@ +# 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 +GOFILES=\ + canonical_text.go\ + keys.go\ + read.go\ + write.go\ + +include ../../../Make.pkg diff --git a/src/pkg/crypto/openpgp/armor/Makefile b/src/pkg/crypto/openpgp/armor/Makefile new file mode 100644 index 000000000..138e314e9 --- /dev/null +++ b/src/pkg/crypto/openpgp/armor/Makefile @@ -0,0 +1,12 @@ +# Copyright 2010 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/armor +GOFILES=\ + armor.go\ + encode.go\ + +include ../../../../Make.pkg diff --git a/src/pkg/crypto/openpgp/armor/armor.go b/src/pkg/crypto/openpgp/armor/armor.go new file mode 100644 index 000000000..9c4180d6d --- /dev/null +++ b/src/pkg/crypto/openpgp/armor/armor.go @@ -0,0 +1,220 @@ +// Copyright 2010 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 armor implements OpenPGP ASCII Armor, see RFC 4880. OpenPGP Armor is +// very similar to PEM except that it has an additional CRC checksum. +package armor + +import ( + "bufio" + "bytes" + "crypto/openpgp/error" + "encoding/base64" + "io" + "os" +) + +// A Block represents an OpenPGP armored structure. +// +// The encoded form is: +// -----BEGIN Type----- +// Headers +// +// base64-encoded Bytes +// '=' base64 encoded checksum +// -----END Type----- +// where Headers is a possibly empty sequence of Key: Value lines. +// +// Since the armored data can be very large, this package presents a streaming +// interface. +type Block struct { + Type string // The type, taken from the preamble (i.e. "PGP SIGNATURE"). + Header map[string]string // Optional headers. + Body io.Reader // A Reader from which the contents can be read + lReader lineReader + oReader openpgpReader +} + +var ArmorCorrupt os.Error = error.StructuralError("armor invalid") + +const crc24Init = 0xb704ce +const crc24Poly = 0x1864cfb +const crc24Mask = 0xffffff + +// crc24 calculates the OpenPGP checksum as specified in RFC 4880, section 6.1 +func crc24(crc uint32, d []byte) uint32 { + for _, b := range d { + crc ^= uint32(b) << 16 + for i := 0; i < 8; i++ { + crc <<= 1 + if crc&0x1000000 != 0 { + crc ^= crc24Poly + } + } + } + return crc +} + +var armorStart = []byte("-----BEGIN ") +var armorEnd = []byte("-----END ") +var armorEndOfLine = []byte("-----") + +// lineReader wraps a line based reader. It watches for the end of an armor +// block and records the expected CRC value. +type lineReader struct { + in *bufio.Reader + buf []byte + eof bool + crc uint32 +} + +func (l *lineReader) Read(p []byte) (n int, err os.Error) { + if l.eof { + return 0, os.EOF + } + + if len(l.buf) > 0 { + n = copy(p, l.buf) + l.buf = l.buf[n:] + return + } + + line, isPrefix, err := l.in.ReadLine() + if err != nil { + return + } + if isPrefix { + return 0, ArmorCorrupt + } + + if len(line) == 5 && line[0] == '=' { + // This is the checksum line + var expectedBytes [3]byte + var m int + m, err = base64.StdEncoding.Decode(expectedBytes[0:], line[1:]) + if m != 3 || err != nil { + return + } + l.crc = uint32(expectedBytes[0])<<16 | + uint32(expectedBytes[1])<<8 | + uint32(expectedBytes[2]) + + line, _, err = l.in.ReadLine() + if err != nil && err != os.EOF { + return + } + if !bytes.HasPrefix(line, armorEnd) { + return 0, ArmorCorrupt + } + + l.eof = true + return 0, os.EOF + } + + if len(line) > 64 { + return 0, ArmorCorrupt + } + + n = copy(p, line) + bytesToSave := len(line) - n + if bytesToSave > 0 { + if cap(l.buf) < bytesToSave { + l.buf = make([]byte, 0, bytesToSave) + } + l.buf = l.buf[0:bytesToSave] + copy(l.buf, line[n:]) + } + + return +} + +// openpgpReader passes Read calls to the underlying base64 decoder, but keeps +// a running CRC of the resulting data and checks the CRC against the value +// found by the lineReader at EOF. +type openpgpReader struct { + lReader *lineReader + b64Reader io.Reader + currentCRC uint32 +} + +func (r *openpgpReader) Read(p []byte) (n int, err os.Error) { + n, err = r.b64Reader.Read(p) + r.currentCRC = crc24(r.currentCRC, p[:n]) + + if err == os.EOF { + if r.lReader.crc != uint32(r.currentCRC&crc24Mask) { + return 0, ArmorCorrupt + } + } + + return +} + +// Decode reads a PGP armored block from the given Reader. It will ignore +// leading garbage. If it doesn't find a block, it will return nil, os.EOF. The +// given Reader is not usable after calling this function: an arbitrary amount +// of data may have been read past the end of the block. +func Decode(in io.Reader) (p *Block, err os.Error) { + r, _ := bufio.NewReaderSize(in, 100) + var line []byte + ignoreNext := false + +TryNextBlock: + p = nil + + // Skip leading garbage + for { + ignoreThis := ignoreNext + line, ignoreNext, err = r.ReadLine() + if err != nil { + return + } + if ignoreNext || ignoreThis { + continue + } + line = bytes.TrimSpace(line) + if len(line) > len(armorStart)+len(armorEndOfLine) && bytes.HasPrefix(line, armorStart) { + break + } + } + + p = new(Block) + p.Type = string(line[len(armorStart) : len(line)-len(armorEndOfLine)]) + p.Header = make(map[string]string) + nextIsContinuation := false + var lastKey string + + // Read headers + for { + isContinuation := nextIsContinuation + line, nextIsContinuation, err = r.ReadLine() + if err != nil { + p = nil + return + } + if isContinuation { + p.Header[lastKey] += string(line) + continue + } + line = bytes.TrimSpace(line) + if len(line) == 0 { + break + } + + i := bytes.Index(line, []byte(": ")) + if i == -1 { + goto TryNextBlock + } + lastKey = string(line[:i]) + p.Header[lastKey] = string(line[i+2:]) + } + + p.lReader.in = r + p.oReader.currentCRC = crc24Init + p.oReader.lReader = &p.lReader + p.oReader.b64Reader = base64.NewDecoder(base64.StdEncoding, &p.lReader) + p.Body = &p.oReader + + return +} diff --git a/src/pkg/crypto/openpgp/armor/armor_test.go b/src/pkg/crypto/openpgp/armor/armor_test.go new file mode 100644 index 000000000..9334e94e9 --- /dev/null +++ b/src/pkg/crypto/openpgp/armor/armor_test.go @@ -0,0 +1,95 @@ +// Copyright 2010 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 armor + +import ( + "bytes" + "hash/adler32" + "io/ioutil" + "testing" +) + +func TestDecodeEncode(t *testing.T) { + buf := bytes.NewBuffer([]byte(armorExample1)) + result, err := Decode(buf) + if err != nil { + t.Error(err) + } + expectedType := "PGP SIGNATURE" + if result.Type != expectedType { + t.Errorf("result.Type: got:%s want:%s", result.Type, expectedType) + } + if len(result.Header) != 1 { + t.Errorf("len(result.Header): got:%d want:1", len(result.Header)) + } + v, ok := result.Header["Version"] + if !ok || v != "GnuPG v1.4.10 (GNU/Linux)" { + t.Errorf("result.Header: got:%#v", result.Header) + } + + contents, err := ioutil.ReadAll(result.Body) + if err != nil { + t.Error(err) + } + + if adler32.Checksum(contents) != 0x27b144be { + t.Errorf("contents: got: %x", contents) + } + + buf = bytes.NewBuffer(nil) + w, err := Encode(buf, result.Type, result.Header) + if err != nil { + t.Error(err) + } + _, err = w.Write(contents) + if err != nil { + t.Error(err) + } + w.Close() + + if !bytes.Equal(buf.Bytes(), []byte(armorExample1)) { + t.Errorf("got: %s\nwant: %s", string(buf.Bytes()), armorExample1) + } +} + +func TestLongHeader(t *testing.T) { + buf := bytes.NewBuffer([]byte(armorLongLine)) + result, err := Decode(buf) + if err != nil { + t.Error(err) + return + } + value, ok := result.Header["Version"] + if !ok { + t.Errorf("missing Version header") + } + if value != longValueExpected { + t.Errorf("got: %s want: %s", value, longValueExpected) + } +} + +const armorExample1 = `-----BEGIN PGP SIGNATURE----- +Version: GnuPG v1.4.10 (GNU/Linux) + +iJwEAAECAAYFAk1Fv/0ACgkQo01+GMIMMbsYTwQAiAw+QAaNfY6WBdplZ/uMAccm +4g+81QPmTSGHnetSb6WBiY13kVzK4HQiZH8JSkmmroMLuGeJwsRTEL4wbjRyUKEt +p1xwUZDECs234F1xiG5enc5SGlRtP7foLBz9lOsjx+LEcA4sTl5/2eZR9zyFZqWW +TxRjs+fJCIFuo71xb1g= +=/teI +-----END PGP SIGNATURE-----` + +const armorLongLine = `-----BEGIN PGP SIGNATURE----- +Version: 0123456789abcdefghijklmnopqrstuvwxyz0123456789abcdefghijklmnopqrstuvwxyz0123456789abcdefghijklmnopqrstuvwxyz0123456789abcdefghijklmnopqrstuvwxyz0123456789abcdefghijklmnopqrstuvwxyz0123456789abcdefghijklmnopqrstuvwxyz0123456789abcdefghijklmnopqrstuvwxyz0123456789abcdefghijklmnopqrstuvwxyz0123456789abcdefghijklmnopqrstuvwxyz + +iQEcBAABAgAGBQJMtFESAAoJEKsQXJGvOPsVj40H/1WW6jaMXv4BW+1ueDSMDwM8 +kx1fLOXbVM5/Kn5LStZNt1jWWnpxdz7eq3uiqeCQjmqUoRde3YbB2EMnnwRbAhpp +cacnAvy9ZQ78OTxUdNW1mhX5bS6q1MTEJnl+DcyigD70HG/yNNQD7sOPMdYQw0TA +byQBwmLwmTsuZsrYqB68QyLHI+DUugn+kX6Hd2WDB62DKa2suoIUIHQQCd/ofwB3 +WfCYInXQKKOSxu2YOg2Eb4kLNhSMc1i9uKUWAH+sdgJh7NBgdoE4MaNtBFkHXRvv +okWuf3+xA9ksp1npSY/mDvgHijmjvtpRDe6iUeqfCn8N9u9CBg8geANgaG8+QA4= +=wfQG +-----END PGP SIGNATURE-----` + +const longValueExpected = "0123456789abcdefghijklmnopqrstuvwxyz0123456789abcdefghijklmnopqrstuvwxyz0123456789abcdefghijklmnopqrstuvwxyz0123456789abcdefghijklmnopqrstuvwxyz0123456789abcdefghijklmnopqrstuvwxyz0123456789abcdefghijklmnopqrstuvwxyz0123456789abcdefghijklmnopqrstuvwxyz0123456789abcdefghijklmnopqrstuvwxyz0123456789abcdefghijklmnopqrstuvwxyz" diff --git a/src/pkg/crypto/openpgp/armor/encode.go b/src/pkg/crypto/openpgp/armor/encode.go new file mode 100644 index 000000000..99dee375e --- /dev/null +++ b/src/pkg/crypto/openpgp/armor/encode.go @@ -0,0 +1,161 @@ +// Copyright 2010 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 armor + +import ( + "encoding/base64" + "io" + "os" +) + +var armorHeaderSep = []byte(": ") +var blockEnd = []byte("\n=") +var newline = []byte("\n") +var armorEndOfLineOut = []byte("-----\n") + +// writeSlices writes its arguments to the given Writer. +func writeSlices(out io.Writer, slices ...[]byte) (err os.Error) { + for _, s := range slices { + _, err = out.Write(s) + if err != nil { + return err + } + } + return +} + +// lineBreaker breaks data across several lines, all of the same byte length +// (except possibly the last). Lines are broken with a single '\n'. +type lineBreaker struct { + lineLength int + line []byte + used int + out io.Writer + haveWritten bool +} + +func newLineBreaker(out io.Writer, lineLength int) *lineBreaker { + return &lineBreaker{ + lineLength: lineLength, + line: make([]byte, lineLength), + used: 0, + out: out, + } +} + +func (l *lineBreaker) Write(b []byte) (n int, err os.Error) { + n = len(b) + + if n == 0 { + return + } + + if l.used == 0 && l.haveWritten { + _, err = l.out.Write([]byte{'\n'}) + if err != nil { + return + } + } + + if l.used+len(b) < l.lineLength { + l.used += copy(l.line[l.used:], b) + return + } + + l.haveWritten = true + _, err = l.out.Write(l.line[0:l.used]) + if err != nil { + return + } + excess := l.lineLength - l.used + l.used = 0 + + _, err = l.out.Write(b[0:excess]) + if err != nil { + return + } + + _, err = l.Write(b[excess:]) + return +} + +func (l *lineBreaker) Close() (err os.Error) { + if l.used > 0 { + _, err = l.out.Write(l.line[0:l.used]) + if err != nil { + return + } + } + + return +} + +// encoding keeps track of a running CRC24 over the data which has been written +// to it and outputs a OpenPGP checksum when closed, followed by an armor +// trailer. +// +// It's built into a stack of io.Writers: +// encoding -> base64 encoder -> lineBreaker -> out +type encoding struct { + out io.Writer + breaker *lineBreaker + b64 io.WriteCloser + crc uint32 + blockType []byte +} + +func (e *encoding) Write(data []byte) (n int, err os.Error) { + e.crc = crc24(e.crc, data) + return e.b64.Write(data) +} + +func (e *encoding) Close() (err os.Error) { + err = e.b64.Close() + if err != nil { + return + } + e.breaker.Close() + + var checksumBytes [3]byte + checksumBytes[0] = byte(e.crc >> 16) + checksumBytes[1] = byte(e.crc >> 8) + checksumBytes[2] = byte(e.crc) + + var b64ChecksumBytes [4]byte + base64.StdEncoding.Encode(b64ChecksumBytes[:], checksumBytes[:]) + + return writeSlices(e.out, blockEnd, b64ChecksumBytes[:], newline, armorEnd, e.blockType, armorEndOfLine) +} + +// Encode returns a WriteCloser which will encode the data written to it in +// OpenPGP armor. +func Encode(out io.Writer, blockType string, headers map[string]string) (w io.WriteCloser, err os.Error) { + bType := []byte(blockType) + err = writeSlices(out, armorStart, bType, armorEndOfLineOut) + if err != nil { + return + } + + for k, v := range headers { + err = writeSlices(out, []byte(k), armorHeaderSep, []byte(v), newline) + if err != nil { + return + } + } + + _, err = out.Write(newline) + if err != nil { + return + } + + e := &encoding{ + out: out, + breaker: newLineBreaker(out, 64), + crc: crc24Init, + blockType: bType, + } + e.b64 = base64.NewEncoder(base64.StdEncoding, e.breaker) + return e, nil +} diff --git a/src/pkg/crypto/openpgp/canonical_text.go b/src/pkg/crypto/openpgp/canonical_text.go new file mode 100644 index 000000000..293eff354 --- /dev/null +++ b/src/pkg/crypto/openpgp/canonical_text.go @@ -0,0 +1,58 @@ +// 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 openpgp + +import ( + "hash" + "os" +) + +// NewCanonicalTextHash reformats text written to it into the canonical +// form and then applies the hash h. See RFC 4880, section 5.2.1. +func NewCanonicalTextHash(h hash.Hash) hash.Hash { + return &canonicalTextHash{h, 0} +} + +type canonicalTextHash struct { + h hash.Hash + s int +} + +var newline = []byte{'\r', '\n'} + +func (cth *canonicalTextHash) Write(buf []byte) (int, os.Error) { + start := 0 + + for i, c := range buf { + switch cth.s { + case 0: + if c == '\r' { + cth.s = 1 + } else if c == '\n' { + cth.h.Write(buf[start:i]) + cth.h.Write(newline) + start = i + 1 + } + case 1: + cth.s = 0 + } + } + + cth.h.Write(buf[start:]) + return len(buf), nil +} + +func (cth *canonicalTextHash) Sum() []byte { + return cth.h.Sum() +} + +func (cth *canonicalTextHash) Reset() { + cth.h.Reset() + cth.s = 0 +} + +func (cth *canonicalTextHash) Size() int { + return cth.h.Size() +} diff --git a/src/pkg/crypto/openpgp/canonical_text_test.go b/src/pkg/crypto/openpgp/canonical_text_test.go new file mode 100644 index 000000000..ccf2910cc --- /dev/null +++ b/src/pkg/crypto/openpgp/canonical_text_test.go @@ -0,0 +1,49 @@ +// 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 openpgp + +import ( + "bytes" + "os" + "testing" +) + +type recordingHash struct { + buf *bytes.Buffer +} + +func (r recordingHash) Write(b []byte) (n int, err os.Error) { + return r.buf.Write(b) +} + +func (r recordingHash) Sum() []byte { + return r.buf.Bytes() +} + +func (r recordingHash) Reset() { + panic("shouldn't be called") +} + +func (r recordingHash) Size() int { + panic("shouldn't be called") +} + +func testCanonicalText(t *testing.T, input, expected string) { + r := recordingHash{bytes.NewBuffer(nil)} + c := NewCanonicalTextHash(r) + c.Write([]byte(input)) + result := c.Sum() + if expected != string(result) { + t.Errorf("input: %x got: %x want: %x", input, result, expected) + } +} + +func TestCanonicalText(t *testing.T) { + testCanonicalText(t, "foo\n", "foo\r\n") + testCanonicalText(t, "foo", "foo") + testCanonicalText(t, "foo\r\n", "foo\r\n") + testCanonicalText(t, "foo\r\nbar", "foo\r\nbar") + testCanonicalText(t, "foo\r\nbar\n\n", "foo\r\nbar\r\n\r\n") +} diff --git a/src/pkg/crypto/openpgp/elgamal/Makefile b/src/pkg/crypto/openpgp/elgamal/Makefile new file mode 100644 index 000000000..f730255f8 --- /dev/null +++ b/src/pkg/crypto/openpgp/elgamal/Makefile @@ -0,0 +1,11 @@ +# 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/elgamal +GOFILES=\ + elgamal.go\ + +include ../../../../Make.pkg diff --git a/src/pkg/crypto/openpgp/elgamal/elgamal.go b/src/pkg/crypto/openpgp/elgamal/elgamal.go new file mode 100644 index 000000000..99a6e3e1f --- /dev/null +++ b/src/pkg/crypto/openpgp/elgamal/elgamal.go @@ -0,0 +1,122 @@ +// 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 elgamal implements ElGamal encryption, suitable for OpenPGP, +// as specified in "A Public-Key Cryptosystem and a Signature Scheme Based on +// Discrete Logarithms," IEEE Transactions on Information Theory, v. IT-31, +// n. 4, 1985, pp. 469-472. +// +// This form of ElGamal embeds PKCS#1 v1.5 padding, which may make it +// unsuitable for other protocols. RSA should be used in preference in any +// case. +package elgamal + +import ( + "big" + "crypto/rand" + "crypto/subtle" + "io" + "os" +) + +// PublicKey represents an ElGamal public key. +type PublicKey struct { + G, P, Y *big.Int +} + +// PrivateKey represents an ElGamal private key. +type PrivateKey struct { + PublicKey + X *big.Int +} + +// Encrypt encrypts the given message to the given public key. The result is a +// pair of integers. Errors can result from reading random, or because msg is +// too large to be encrypted to the public key. +func Encrypt(random io.Reader, pub *PublicKey, msg []byte) (c1, c2 *big.Int, err os.Error) { + pLen := (pub.P.BitLen() + 7) / 8 + if len(msg) > pLen-11 { + err = os.NewError("elgamal: message too long") + return + } + + // EM = 0x02 || PS || 0x00 || M + em := make([]byte, pLen-1) + em[0] = 2 + ps, mm := em[1:len(em)-len(msg)-1], em[len(em)-len(msg):] + err = nonZeroRandomBytes(ps, random) + if err != nil { + return + } + em[len(em)-len(msg)-1] = 0 + copy(mm, msg) + + m := new(big.Int).SetBytes(em) + + k, err := rand.Int(random, pub.P) + if err != nil { + return + } + + c1 = new(big.Int).Exp(pub.G, k, pub.P) + s := new(big.Int).Exp(pub.Y, k, pub.P) + c2 = s.Mul(s, m) + c2.Mod(c2, pub.P) + + return +} + +// Decrypt takes two integers, resulting from an ElGamal encryption, and +// returns the plaintext of the message. An error can result only if the +// ciphertext is invalid. Users should keep in mind that this is a padding +// oracle and thus, if exposed to an adaptive chosen ciphertext attack, can +// be used to break the cryptosystem. See ``Chosen Ciphertext Attacks +// Against Protocols Based on the RSA Encryption Standard PKCS #1'', Daniel +// Bleichenbacher, Advances in Cryptology (Crypto '98), +func Decrypt(priv *PrivateKey, c1, c2 *big.Int) (msg []byte, err os.Error) { + s := new(big.Int).Exp(c1, priv.X, priv.P) + s.ModInverse(s, priv.P) + s.Mul(s, c2) + s.Mod(s, priv.P) + em := s.Bytes() + + firstByteIsTwo := subtle.ConstantTimeByteEq(em[0], 2) + + // The remainder of the plaintext must be a string of non-zero random + // octets, followed by a 0, followed by the message. + // lookingForIndex: 1 iff we are still looking for the zero. + // index: the offset of the first zero byte. + var lookingForIndex, index int + lookingForIndex = 1 + + for i := 1; i < len(em); i++ { + equals0 := subtle.ConstantTimeByteEq(em[i], 0) + index = subtle.ConstantTimeSelect(lookingForIndex&equals0, i, index) + lookingForIndex = subtle.ConstantTimeSelect(equals0, 0, lookingForIndex) + } + + if firstByteIsTwo != 1 || lookingForIndex != 0 || index < 9 { + return nil, os.NewError("elgamal: decryption error") + } + return em[index+1:], nil +} + +// nonZeroRandomBytes fills the given slice with non-zero random octets. +func nonZeroRandomBytes(s []byte, rand io.Reader) (err os.Error) { + _, err = io.ReadFull(rand, s) + if err != nil { + return + } + + for i := 0; i < len(s); i++ { + for s[i] == 0 { + _, err = io.ReadFull(rand, s[i:i+1]) + if err != nil { + return + } + } + } + + return +} diff --git a/src/pkg/crypto/openpgp/elgamal/elgamal_test.go b/src/pkg/crypto/openpgp/elgamal/elgamal_test.go new file mode 100644 index 000000000..101121aa6 --- /dev/null +++ b/src/pkg/crypto/openpgp/elgamal/elgamal_test.go @@ -0,0 +1,49 @@ +// 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 elgamal + +import ( + "big" + "bytes" + "crypto/rand" + "testing" +) + +// This is the 1024-bit MODP group from RFC 5114, section 2.1: +const primeHex = "B10B8F96A080E01DDE92DE5EAE5D54EC52C99FBCFB06A3C69A6A9DCA52D23B616073E28675A23D189838EF1E2EE652C013ECB4AEA906112324975C3CD49B83BFACCBDD7D90C4BD7098488E9C219A73724EFFD6FAE5644738FAA31A4FF55BCCC0A151AF5F0DC8B4BD45BF37DF365C1A65E68CFDA76D4DA708DF1FB2BC2E4A4371" + +const generatorHex = "A4D1CBD5C3FD34126765A442EFB99905F8104DD258AC507FD6406CFF14266D31266FEA1E5C41564B777E690F5504F213160217B4B01B886A5E91547F9E2749F4D7FBD7D3B9A92EE1909D0D2263F80A76A6A24C087A091F531DBF0A0169B6A28AD662A4D18E73AFA32D779D5918D08BC8858F4DCEF97C2A24855E6EEB22B3B2E5" + +func fromHex(hex string) *big.Int { + n, ok := new(big.Int).SetString(hex, 16) + if !ok { + panic("failed to parse hex number") + } + return n +} + +func TestEncryptDecrypt(t *testing.T) { + priv := &PrivateKey{ + PublicKey: PublicKey{ + G: fromHex(generatorHex), + P: fromHex(primeHex), + }, + X: fromHex("42"), + } + priv.Y = new(big.Int).Exp(priv.G, priv.X, priv.P) + + message := []byte("hello world") + c1, c2, err := Encrypt(rand.Reader, &priv.PublicKey, message) + if err != nil { + t.Errorf("error encrypting: %s", err) + } + message2, err := Decrypt(priv, c1, c2) + if err != nil { + t.Errorf("error decrypting: %s", err) + } + if !bytes.Equal(message2, message) { + t.Errorf("decryption failed, got: %x, want: %x", message2, message) + } +} diff --git a/src/pkg/crypto/openpgp/error/Makefile b/src/pkg/crypto/openpgp/error/Makefile new file mode 100644 index 000000000..8c370a089 --- /dev/null +++ b/src/pkg/crypto/openpgp/error/Makefile @@ -0,0 +1,11 @@ +# Copyright 2010 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/error +GOFILES=\ + error.go\ + +include ../../../../Make.pkg diff --git a/src/pkg/crypto/openpgp/error/error.go b/src/pkg/crypto/openpgp/error/error.go new file mode 100644 index 000000000..3759ce161 --- /dev/null +++ b/src/pkg/crypto/openpgp/error/error.go @@ -0,0 +1,64 @@ +// Copyright 2010 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 error contains common error types for the OpenPGP packages. +package error + +import ( + "strconv" +) + +// A StructuralError is returned when OpenPGP data is found to be syntactically +// invalid. +type StructuralError string + +func (s StructuralError) String() string { + return "OpenPGP data invalid: " + string(s) +} + +// UnsupportedError indicates that, although the OpenPGP data is valid, it +// makes use of currently unimplemented features. +type UnsupportedError string + +func (s UnsupportedError) String() string { + return "OpenPGP feature unsupported: " + string(s) +} + +// InvalidArgumentError indicates that the caller is in error and passed an +// incorrect value. +type InvalidArgumentError string + +func (i InvalidArgumentError) String() string { + return "OpenPGP argument invalid: " + string(i) +} + +// SignatureError indicates that a syntactically valid signature failed to +// validate. +type SignatureError string + +func (b SignatureError) String() string { + return "OpenPGP signature invalid: " + string(b) +} + +type keyIncorrect int + +func (ki keyIncorrect) String() string { + return "the given key was incorrect" +} + +var KeyIncorrectError = keyIncorrect(0) + +type unknownIssuer int + +func (unknownIssuer) String() string { + return "signature make by unknown entity" +} + +var UnknownIssuerError = unknownIssuer(0) + +type UnknownPacketTypeError uint8 + +func (upte UnknownPacketTypeError) String() string { + return "unknown OpenPGP packet type: " + strconv.Itoa(int(upte)) +} diff --git a/src/pkg/crypto/openpgp/keys.go b/src/pkg/crypto/openpgp/keys.go new file mode 100644 index 000000000..c70fb7927 --- /dev/null +++ b/src/pkg/crypto/openpgp/keys.go @@ -0,0 +1,545 @@ +// 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 openpgp + +import ( + "crypto" + "crypto/openpgp/armor" + "crypto/openpgp/error" + "crypto/openpgp/packet" + "crypto/rsa" + "io" + "os" + "time" +) + +// PublicKeyType is the armor type for a PGP public key. +var PublicKeyType = "PGP PUBLIC KEY BLOCK" +// PrivateKeyType is the armor type for a PGP private key. +var PrivateKeyType = "PGP PRIVATE KEY BLOCK" + +// An Entity represents the components of an OpenPGP key: a primary public key +// (which must be a signing key), one or more identities claimed by that key, +// and zero or more subkeys, which may be encryption keys. +type Entity struct { + PrimaryKey *packet.PublicKey + PrivateKey *packet.PrivateKey + Identities map[string]*Identity // indexed by Identity.Name + Subkeys []Subkey +} + +// An Identity represents an identity claimed by an Entity and zero or more +// assertions by other entities about that claim. +type Identity struct { + Name string // by convention, has the form "Full Name (comment) <email@example.com>" + UserId *packet.UserId + SelfSignature *packet.Signature + Signatures []*packet.Signature +} + +// A Subkey is an additional public key in an Entity. Subkeys can be used for +// encryption. +type Subkey struct { + PublicKey *packet.PublicKey + PrivateKey *packet.PrivateKey + Sig *packet.Signature +} + +// A Key identifies a specific public key in an Entity. This is either the +// Entity's primary key or a subkey. +type Key struct { + Entity *Entity + PublicKey *packet.PublicKey + PrivateKey *packet.PrivateKey + SelfSignature *packet.Signature +} + +// A KeyRing provides access to public and private keys. +type KeyRing interface { + // KeysById returns the set of keys that have the given key id. + KeysById(id uint64) []Key + // DecryptionKeys returns all private keys that are valid for + // decryption. + DecryptionKeys() []Key +} + +// primaryIdentity returns the Identity marked as primary or the first identity +// if none are so marked. +func (e *Entity) primaryIdentity() *Identity { + var firstIdentity *Identity + for _, ident := range e.Identities { + if firstIdentity == nil { + firstIdentity = ident + } + if ident.SelfSignature.IsPrimaryId != nil && *ident.SelfSignature.IsPrimaryId { + return ident + } + } + return firstIdentity +} + +// encryptionKey returns the best candidate Key for encrypting a message to the +// given Entity. +func (e *Entity) encryptionKey() Key { + candidateSubkey := -1 + + for i, subkey := range e.Subkeys { + if subkey.Sig.FlagsValid && subkey.Sig.FlagEncryptCommunications && subkey.PublicKey.PubKeyAlgo.CanEncrypt() { + candidateSubkey = i + break + } + } + + i := e.primaryIdentity() + + if e.PrimaryKey.PubKeyAlgo.CanEncrypt() { + // If we don't have any candidate subkeys for encryption and + // the primary key doesn't have any usage metadata then we + // assume that the primary key is ok. Or, if the primary key is + // marked as ok to encrypt to, then we can obviously use it. + if candidateSubkey == -1 && !i.SelfSignature.FlagsValid || i.SelfSignature.FlagEncryptCommunications && i.SelfSignature.FlagsValid { + return Key{e, e.PrimaryKey, e.PrivateKey, i.SelfSignature} + } + } + + if candidateSubkey != -1 { + subkey := e.Subkeys[candidateSubkey] + return Key{e, subkey.PublicKey, subkey.PrivateKey, subkey.Sig} + } + + // This Entity appears to be signing only. + return Key{} +} + +// signingKey return the best candidate Key for signing a message with this +// Entity. +func (e *Entity) signingKey() Key { + candidateSubkey := -1 + + for i, subkey := range e.Subkeys { + if subkey.Sig.FlagsValid && subkey.Sig.FlagSign && subkey.PublicKey.PubKeyAlgo.CanSign() { + candidateSubkey = i + break + } + } + + i := e.primaryIdentity() + + // If we have no candidate subkey then we assume that it's ok to sign + // with the primary key. + if candidateSubkey == -1 || i.SelfSignature.FlagsValid && i.SelfSignature.FlagSign { + return Key{e, e.PrimaryKey, e.PrivateKey, i.SelfSignature} + } + + subkey := e.Subkeys[candidateSubkey] + return Key{e, subkey.PublicKey, subkey.PrivateKey, subkey.Sig} +} + +// An EntityList contains one or more Entities. +type EntityList []*Entity + +// KeysById returns the set of keys that have the given key id. +func (el EntityList) KeysById(id uint64) (keys []Key) { + for _, e := range el { + if e.PrimaryKey.KeyId == id { + var selfSig *packet.Signature + for _, ident := range e.Identities { + if selfSig == nil { + selfSig = ident.SelfSignature + } else if ident.SelfSignature.IsPrimaryId != nil && *ident.SelfSignature.IsPrimaryId { + selfSig = ident.SelfSignature + break + } + } + keys = append(keys, Key{e, e.PrimaryKey, e.PrivateKey, selfSig}) + } + + for _, subKey := range e.Subkeys { + if subKey.PublicKey.KeyId == id { + keys = append(keys, Key{e, subKey.PublicKey, subKey.PrivateKey, subKey.Sig}) + } + } + } + return +} + +// DecryptionKeys returns all private keys that are valid for decryption. +func (el EntityList) DecryptionKeys() (keys []Key) { + for _, e := range el { + for _, subKey := range e.Subkeys { + if subKey.PrivateKey != nil && (!subKey.Sig.FlagsValid || subKey.Sig.FlagEncryptStorage || subKey.Sig.FlagEncryptCommunications) { + keys = append(keys, Key{e, subKey.PublicKey, subKey.PrivateKey, subKey.Sig}) + } + } + } + return +} + +// ReadArmoredKeyRing reads one or more public/private keys from an armor keyring file. +func ReadArmoredKeyRing(r io.Reader) (EntityList, os.Error) { + block, err := armor.Decode(r) + if err == os.EOF { + return nil, error.InvalidArgumentError("no armored data found") + } + if err != nil { + return nil, err + } + if block.Type != PublicKeyType && block.Type != PrivateKeyType { + return nil, error.InvalidArgumentError("expected public or private key block, got: " + block.Type) + } + + return ReadKeyRing(block.Body) +} + +// ReadKeyRing reads one or more public/private keys. Unsupported keys are +// ignored as long as at least a single valid key is found. +func ReadKeyRing(r io.Reader) (el EntityList, err os.Error) { + packets := packet.NewReader(r) + var lastUnsupportedError os.Error + + for { + var e *Entity + e, err = readEntity(packets) + if err != nil { + if _, ok := err.(error.UnsupportedError); ok { + lastUnsupportedError = err + err = readToNextPublicKey(packets) + } + if err == os.EOF { + err = nil + break + } + if err != nil { + el = nil + break + } + } else { + el = append(el, e) + } + } + + if len(el) == 0 && err == nil { + err = lastUnsupportedError + } + return +} + +// readToNextPublicKey reads packets until the start of the entity and leaves +// the first packet of the new entity in the Reader. +func readToNextPublicKey(packets *packet.Reader) (err os.Error) { + var p packet.Packet + for { + p, err = packets.Next() + if err == os.EOF { + return + } else if err != nil { + if _, ok := err.(error.UnsupportedError); ok { + err = nil + continue + } + return + } + + if pk, ok := p.(*packet.PublicKey); ok && !pk.IsSubkey { + packets.Unread(p) + return + } + } + + panic("unreachable") +} + +// readEntity reads an entity (public key, identities, subkeys etc) from the +// given Reader. +func readEntity(packets *packet.Reader) (*Entity, os.Error) { + e := new(Entity) + e.Identities = make(map[string]*Identity) + + p, err := packets.Next() + if err != nil { + return nil, err + } + + var ok bool + if e.PrimaryKey, ok = p.(*packet.PublicKey); !ok { + if e.PrivateKey, ok = p.(*packet.PrivateKey); !ok { + packets.Unread(p) + return nil, error.StructuralError("first packet was not a public/private key") + } else { + e.PrimaryKey = &e.PrivateKey.PublicKey + } + } + + if !e.PrimaryKey.PubKeyAlgo.CanSign() { + return nil, error.StructuralError("primary key cannot be used for signatures") + } + + var current *Identity +EachPacket: + for { + p, err := packets.Next() + if err == os.EOF { + break + } else if err != nil { + return nil, err + } + + switch pkt := p.(type) { + case *packet.UserId: + current = new(Identity) + current.Name = pkt.Id + current.UserId = pkt + e.Identities[pkt.Id] = current + + for { + p, err = packets.Next() + if err == os.EOF { + return nil, io.ErrUnexpectedEOF + } else if err != nil { + return nil, err + } + + sig, ok := p.(*packet.Signature) + if !ok { + return nil, error.StructuralError("user ID packet not followed by self-signature") + } + + if (sig.SigType == packet.SigTypePositiveCert || sig.SigType == packet.SigTypeGenericCert) && sig.IssuerKeyId != nil && *sig.IssuerKeyId == e.PrimaryKey.KeyId { + if err = e.PrimaryKey.VerifyUserIdSignature(pkt.Id, sig); err != nil { + return nil, error.StructuralError("user ID self-signature invalid: " + err.String()) + } + current.SelfSignature = sig + break + } + current.Signatures = append(current.Signatures, sig) + } + case *packet.Signature: + if current == nil { + return nil, error.StructuralError("signature packet found before user id packet") + } + current.Signatures = append(current.Signatures, pkt) + case *packet.PrivateKey: + if pkt.IsSubkey == false { + packets.Unread(p) + break EachPacket + } + err = addSubkey(e, packets, &pkt.PublicKey, pkt) + if err != nil { + return nil, err + } + case *packet.PublicKey: + if pkt.IsSubkey == false { + packets.Unread(p) + break EachPacket + } + err = addSubkey(e, packets, pkt, nil) + if err != nil { + return nil, err + } + default: + // we ignore unknown packets + } + } + + if len(e.Identities) == 0 { + return nil, error.StructuralError("entity without any identities") + } + + return e, nil +} + +func addSubkey(e *Entity, packets *packet.Reader, pub *packet.PublicKey, priv *packet.PrivateKey) os.Error { + var subKey Subkey + subKey.PublicKey = pub + subKey.PrivateKey = priv + p, err := packets.Next() + if err == os.EOF { + return io.ErrUnexpectedEOF + } + if err != nil { + return error.StructuralError("subkey signature invalid: " + err.String()) + } + var ok bool + subKey.Sig, ok = p.(*packet.Signature) + if !ok { + return error.StructuralError("subkey packet not followed by signature") + } + if subKey.Sig.SigType != packet.SigTypeSubkeyBinding { + return error.StructuralError("subkey signature with wrong type") + } + err = e.PrimaryKey.VerifyKeySignature(subKey.PublicKey, subKey.Sig) + if err != nil { + return error.StructuralError("subkey signature invalid: " + err.String()) + } + e.Subkeys = append(e.Subkeys, subKey) + return nil +} + +const defaultRSAKeyBits = 2048 + +// NewEntity returns an Entity that contains a fresh RSA/RSA keypair with a +// single identity composed of the given full name, comment and email, any of +// which may be empty but must not contain any of "()<>\x00". +func NewEntity(rand io.Reader, currentTimeSecs int64, name, comment, email string) (*Entity, os.Error) { + uid := packet.NewUserId(name, comment, email) + if uid == nil { + return nil, error.InvalidArgumentError("user id field contained invalid characters") + } + signingPriv, err := rsa.GenerateKey(rand, defaultRSAKeyBits) + if err != nil { + return nil, err + } + encryptingPriv, err := rsa.GenerateKey(rand, defaultRSAKeyBits) + if err != nil { + return nil, err + } + + t := uint32(currentTimeSecs) + + e := &Entity{ + PrimaryKey: packet.NewRSAPublicKey(t, &signingPriv.PublicKey, false /* not a subkey */ ), + PrivateKey: packet.NewRSAPrivateKey(t, signingPriv, false /* not a subkey */ ), + Identities: make(map[string]*Identity), + } + isPrimaryId := true + e.Identities[uid.Id] = &Identity{ + Name: uid.Name, + UserId: uid, + SelfSignature: &packet.Signature{ + CreationTime: t, + SigType: packet.SigTypePositiveCert, + PubKeyAlgo: packet.PubKeyAlgoRSA, + Hash: crypto.SHA256, + IsPrimaryId: &isPrimaryId, + FlagsValid: true, + FlagSign: true, + FlagCertify: true, + IssuerKeyId: &e.PrimaryKey.KeyId, + }, + } + + e.Subkeys = make([]Subkey, 1) + e.Subkeys[0] = Subkey{ + PublicKey: packet.NewRSAPublicKey(t, &encryptingPriv.PublicKey, true /* is a subkey */ ), + PrivateKey: packet.NewRSAPrivateKey(t, encryptingPriv, true /* is a subkey */ ), + Sig: &packet.Signature{ + CreationTime: t, + SigType: packet.SigTypeSubkeyBinding, + PubKeyAlgo: packet.PubKeyAlgoRSA, + Hash: crypto.SHA256, + FlagsValid: true, + FlagEncryptStorage: true, + FlagEncryptCommunications: true, + IssuerKeyId: &e.PrimaryKey.KeyId, + }, + } + + return e, nil +} + +// SerializePrivate serializes an Entity, including private key material, to +// the given Writer. For now, it must only be used on an Entity returned from +// NewEntity. +func (e *Entity) SerializePrivate(w io.Writer) (err os.Error) { + err = e.PrivateKey.Serialize(w) + if err != nil { + return + } + for _, ident := range e.Identities { + err = ident.UserId.Serialize(w) + if err != nil { + return + } + err = ident.SelfSignature.SignUserId(ident.UserId.Id, e.PrimaryKey, e.PrivateKey) + if err != nil { + return + } + err = ident.SelfSignature.Serialize(w) + if err != nil { + return + } + } + for _, subkey := range e.Subkeys { + err = subkey.PrivateKey.Serialize(w) + if err != nil { + return + } + err = subkey.Sig.SignKey(subkey.PublicKey, e.PrivateKey) + if err != nil { + return + } + err = subkey.Sig.Serialize(w) + if err != nil { + return + } + } + return nil +} + +// Serialize writes the public part of the given Entity to w. (No private +// key material will be output). +func (e *Entity) Serialize(w io.Writer) os.Error { + err := e.PrimaryKey.Serialize(w) + if err != nil { + return err + } + for _, ident := range e.Identities { + err = ident.UserId.Serialize(w) + if err != nil { + return err + } + err = ident.SelfSignature.Serialize(w) + if err != nil { + return err + } + for _, sig := range ident.Signatures { + err = sig.Serialize(w) + if err != nil { + return err + } + } + } + for _, subkey := range e.Subkeys { + err = subkey.PublicKey.Serialize(w) + if err != nil { + return err + } + err = subkey.Sig.Serialize(w) + if err != nil { + return err + } + } + return nil +} + +// SignIdentity adds a signature to e, from signer, attesting that identity is +// associated with e. The provided identity must already be an element of +// e.Identities and the private key of signer must have been decrypted if +// necessary. +func (e *Entity) SignIdentity(identity string, signer *Entity) os.Error { + if signer.PrivateKey == nil { + return error.InvalidArgumentError("signing Entity must have a private key") + } + if signer.PrivateKey.Encrypted { + return error.InvalidArgumentError("signing Entity's private key must be decrypted") + } + ident, ok := e.Identities[identity] + if !ok { + return error.InvalidArgumentError("given identity string not found in Entity") + } + + sig := &packet.Signature{ + SigType: packet.SigTypeGenericCert, + PubKeyAlgo: signer.PrivateKey.PubKeyAlgo, + Hash: crypto.SHA256, + CreationTime: uint32(time.Seconds()), + IssuerKeyId: &signer.PrivateKey.KeyId, + } + if err := sig.SignKey(e.PrimaryKey, signer.PrivateKey); err != nil { + return err + } + ident.Signatures = append(ident.Signatures, sig) + return nil +} 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 = "9501fe044cc349a8010400b70ca0010e98c090008d45d1ee8f9113bd5861fd57b88bacb7c68658747663f1e1a3b5a98f32fda6472373c024b97359cd2efc88ff60f77751adfbf6af5e615e6a1408cfad8bf0cea30b0d5f53aa27ad59089ba9b15b7ebc2777a25d7b436144027e3bcd203909f147d0e332b240cf63d3395f5dfe0df0a6c04e8655af7eacdf0011010001fe0303024a252e7d475fd445607de39a265472aa74a9320ba2dac395faa687e9e0336aeb7e9a7397e511b5afd9dc84557c80ac0f3d4d7bfec5ae16f20d41c8c84a04552a33870b930420e230e179564f6d19bb153145e76c33ae993886c388832b0fa042ddda7f133924f3854481533e0ede31d51278c0519b29abc3bf53da673e13e3e1214b52413d179d7f66deee35cac8eacb060f78379d70ef4af8607e68131ff529439668fc39c9ce6dfef8a5ac234d234802cbfb749a26107db26406213ae5c06d4673253a3cbee1fcbae58d6ab77e38d6e2c0e7c6317c48e054edadb5a40d0d48acb44643d998139a8a66bb820be1f3f80185bc777d14b5954b60effe2448a036d565c6bc0b915fcea518acdd20ab07bc1529f561c58cd044f723109b93f6fd99f876ff891d64306b5d08f48bab59f38695e9109c4dec34013ba3153488ce070268381ba923ee1eb77125b36afcb4347ec3478c8f2735b06ef17351d872e577fa95d0c397c88c71b59629a36aec" + +// Generated by `gpg --export-secret-keys` followed by a manual extraction of +// the ElGamal subkey from the packets. +const privKeyElGamalHex = "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" 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 = "9901a2044d432f89110400cd581334f0d7a1e1bdc8b9d6d8c0baf68793632735d2bb0903224cbaa1dfbf35a60ee7a13b92643421e1eb41aa8d79bea19a115a677f6b8ba3c7818ce53a6c2a24a1608bd8b8d6e55c5090cbde09dd26e356267465ae25e69ec8bdd57c7bbb2623e4d73336f73a0a9098f7f16da2e25252130fd694c0e8070c55a812a423ae7f00a0ebf50e70c2f19c3520a551bd4b08d30f23530d3d03ff7d0bf4a53a64a09dc5e6e6e35854b7d70c882b0c60293401958b1bd9e40abec3ea05ba87cf64899299d4bd6aa7f459c201d3fbbd6c82004bdc5e8a9eb8082d12054cc90fa9d4ec251a843236a588bf49552441817436c4f43326966fe85447d4e6d0acf8fa1ef0f014730770603ad7634c3088dc52501c237328417c31c89ed70400b2f1a98b0bf42f11fefc430704bebbaa41d9f355600c3facee1e490f64208e0e094ea55e3a598a219a58500bf78ac677b670a14f4e47e9cf8eab4f368cc1ddcaa18cc59309d4cc62dd4f680e73e6cc3e1ce87a84d0925efbcb26c575c093fc42eecf45135fabf6403a25c2016e1774c0484e440a18319072c617cc97ac0a3bb0" 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) + } + } +} diff --git a/src/pkg/crypto/openpgp/read.go b/src/pkg/crypto/openpgp/read.go new file mode 100644 index 000000000..d95f613c6 --- /dev/null +++ b/src/pkg/crypto/openpgp/read.go @@ -0,0 +1,415 @@ +// 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 openpgp implements high level operations on OpenPGP messages. +package openpgp + +import ( + "crypto" + "crypto/openpgp/armor" + "crypto/openpgp/error" + "crypto/openpgp/packet" + _ "crypto/sha256" + "hash" + "io" + "os" + "strconv" +) + +// SignatureType is the armor type for a PGP signature. +var SignatureType = "PGP SIGNATURE" + +// readArmored reads an armored block with the given type. +func readArmored(r io.Reader, expectedType string) (body io.Reader, err os.Error) { + block, err := armor.Decode(r) + if err != nil { + return + } + + if block.Type != expectedType { + return nil, error.InvalidArgumentError("expected '" + expectedType + "', got: " + block.Type) + } + + return block.Body, nil +} + +// MessageDetails contains the result of parsing an OpenPGP encrypted and/or +// signed message. +type MessageDetails struct { + IsEncrypted bool // true if the message was encrypted. + EncryptedToKeyIds []uint64 // the list of recipient key ids. + IsSymmetricallyEncrypted bool // true if a passphrase could have decrypted the message. + DecryptedWith Key // the private key used to decrypt the message, if any. + IsSigned bool // true if the message is signed. + SignedByKeyId uint64 // the key id of the signer, if any. + SignedBy *Key // the key of the signer, if available. + LiteralData *packet.LiteralData // the metadata of the contents + UnverifiedBody io.Reader // the contents of the message. + + // If IsSigned is true and SignedBy is non-zero then the signature will + // be verified as UnverifiedBody is read. The signature cannot be + // checked until the whole of UnverifiedBody is read so UnverifiedBody + // must be consumed until EOF before the data can trusted. Even if a + // message isn't signed (or the signer is unknown) the data may contain + // an authentication code that is only checked once UnverifiedBody has + // been consumed. Once EOF has been seen, the following fields are + // valid. (An authentication code failure is reported as a + // SignatureError error when reading from UnverifiedBody.) + SignatureError os.Error // nil if the signature is good. + Signature *packet.Signature // the signature packet itself. + + decrypted io.ReadCloser +} + +// A PromptFunction is used as a callback by functions that may need to decrypt +// a private key, or prompt for a passphrase. It is called with a list of +// acceptable, encrypted private keys and a boolean that indicates whether a +// passphrase is usable. It should either decrypt a private key or return a +// passphrase to try. If the decrypted private key or given passphrase isn't +// correct, the function will be called again, forever. Any error returned will +// be passed up. +type PromptFunction func(keys []Key, symmetric bool) ([]byte, os.Error) + +// A keyEnvelopePair is used to store a private key with the envelope that +// contains a symmetric key, encrypted with that key. +type keyEnvelopePair struct { + key Key + encryptedKey *packet.EncryptedKey +} + +// ReadMessage parses an OpenPGP message that may be signed and/or encrypted. +// The given KeyRing should contain both public keys (for signature +// verification) and, possibly encrypted, private keys for decrypting. +func ReadMessage(r io.Reader, keyring KeyRing, prompt PromptFunction) (md *MessageDetails, err os.Error) { + var p packet.Packet + + var symKeys []*packet.SymmetricKeyEncrypted + var pubKeys []keyEnvelopePair + var se *packet.SymmetricallyEncrypted + + packets := packet.NewReader(r) + md = new(MessageDetails) + md.IsEncrypted = true + + // The message, if encrypted, starts with a number of packets + // containing an encrypted decryption key. The decryption key is either + // encrypted to a public key, or with a passphrase. This loop + // collects these packets. +ParsePackets: + for { + p, err = packets.Next() + if err != nil { + return nil, err + } + switch p := p.(type) { + case *packet.SymmetricKeyEncrypted: + // This packet contains the decryption key encrypted with a passphrase. + md.IsSymmetricallyEncrypted = true + symKeys = append(symKeys, p) + case *packet.EncryptedKey: + // This packet contains the decryption key encrypted to a public key. + md.EncryptedToKeyIds = append(md.EncryptedToKeyIds, p.KeyId) + switch p.Algo { + case packet.PubKeyAlgoRSA, packet.PubKeyAlgoRSAEncryptOnly, packet.PubKeyAlgoElGamal: + break + default: + continue + } + var keys []Key + if p.KeyId == 0 { + keys = keyring.DecryptionKeys() + } else { + keys = keyring.KeysById(p.KeyId) + } + for _, k := range keys { + pubKeys = append(pubKeys, keyEnvelopePair{k, p}) + } + case *packet.SymmetricallyEncrypted: + se = p + break ParsePackets + case *packet.Compressed, *packet.LiteralData, *packet.OnePassSignature: + // This message isn't encrypted. + if len(symKeys) != 0 || len(pubKeys) != 0 { + return nil, error.StructuralError("key material not followed by encrypted message") + } + packets.Unread(p) + return readSignedMessage(packets, nil, keyring) + } + } + + var candidates []Key + var decrypted io.ReadCloser + + // Now that we have the list of encrypted keys we need to decrypt at + // least one of them or, if we cannot, we need to call the prompt + // function so that it can decrypt a key or give us a passphrase. +FindKey: + for { + // See if any of the keys already have a private key available + candidates = candidates[:0] + candidateFingerprints := make(map[string]bool) + + for _, pk := range pubKeys { + if pk.key.PrivateKey == nil { + continue + } + if !pk.key.PrivateKey.Encrypted { + if len(pk.encryptedKey.Key) == 0 { + pk.encryptedKey.Decrypt(pk.key.PrivateKey) + } + if len(pk.encryptedKey.Key) == 0 { + continue + } + decrypted, err = se.Decrypt(pk.encryptedKey.CipherFunc, pk.encryptedKey.Key) + if err != nil && err != error.KeyIncorrectError { + return nil, err + } + if decrypted != nil { + md.DecryptedWith = pk.key + break FindKey + } + } else { + fpr := string(pk.key.PublicKey.Fingerprint[:]) + if v := candidateFingerprints[fpr]; v { + continue + } + candidates = append(candidates, pk.key) + candidateFingerprints[fpr] = true + } + } + + if len(candidates) == 0 && len(symKeys) == 0 { + return nil, error.KeyIncorrectError + } + + if prompt == nil { + return nil, error.KeyIncorrectError + } + + passphrase, err := prompt(candidates, len(symKeys) != 0) + if err != nil { + return nil, err + } + + // Try the symmetric passphrase first + if len(symKeys) != 0 && passphrase != nil { + for _, s := range symKeys { + err = s.Decrypt(passphrase) + if err == nil && !s.Encrypted { + decrypted, err = se.Decrypt(s.CipherFunc, s.Key) + if err != nil && err != error.KeyIncorrectError { + return nil, err + } + if decrypted != nil { + break FindKey + } + } + + } + } + } + + md.decrypted = decrypted + packets.Push(decrypted) + return readSignedMessage(packets, md, keyring) +} + +// readSignedMessage reads a possibly signed message if mdin is non-zero then +// that structure is updated and returned. Otherwise a fresh MessageDetails is +// used. +func readSignedMessage(packets *packet.Reader, mdin *MessageDetails, keyring KeyRing) (md *MessageDetails, err os.Error) { + if mdin == nil { + mdin = new(MessageDetails) + } + md = mdin + + var p packet.Packet + var h hash.Hash + var wrappedHash hash.Hash +FindLiteralData: + for { + p, err = packets.Next() + if err != nil { + return nil, err + } + switch p := p.(type) { + case *packet.Compressed: + packets.Push(p.Body) + case *packet.OnePassSignature: + if !p.IsLast { + return nil, error.UnsupportedError("nested signatures") + } + + h, wrappedHash, err = hashForSignature(p.Hash, p.SigType) + if err != nil { + md = nil + return + } + + md.IsSigned = true + md.SignedByKeyId = p.KeyId + keys := keyring.KeysById(p.KeyId) + for i, key := range keys { + if key.SelfSignature.FlagsValid && !key.SelfSignature.FlagSign { + continue + } + md.SignedBy = &keys[i] + break + } + case *packet.LiteralData: + md.LiteralData = p + break FindLiteralData + } + } + + if md.SignedBy != nil { + md.UnverifiedBody = &signatureCheckReader{packets, h, wrappedHash, md} + } else if md.decrypted != nil { + md.UnverifiedBody = checkReader{md} + } else { + md.UnverifiedBody = md.LiteralData.Body + } + + return md, nil +} + +// hashForSignature returns a pair of hashes that can be used to verify a +// signature. The signature may specify that the contents of the signed message +// should be preprocessed (i.e. to normalize line endings). Thus this function +// returns two hashes. The second should be used to hash the message itself and +// performs any needed preprocessing. +func hashForSignature(hashId crypto.Hash, sigType packet.SignatureType) (hash.Hash, hash.Hash, os.Error) { + h := hashId.New() + if h == nil { + return nil, nil, error.UnsupportedError("hash not available: " + strconv.Itoa(int(hashId))) + } + + switch sigType { + case packet.SigTypeBinary: + return h, h, nil + case packet.SigTypeText: + return h, NewCanonicalTextHash(h), nil + } + + return nil, nil, error.UnsupportedError("unsupported signature type: " + strconv.Itoa(int(sigType))) +} + +// checkReader wraps an io.Reader from a LiteralData packet. When it sees EOF +// it closes the ReadCloser from any SymmetricallyEncrypted packet to trigger +// MDC checks. +type checkReader struct { + md *MessageDetails +} + +func (cr checkReader) Read(buf []byte) (n int, err os.Error) { + n, err = cr.md.LiteralData.Body.Read(buf) + if err == os.EOF { + mdcErr := cr.md.decrypted.Close() + if mdcErr != nil { + err = mdcErr + } + } + return +} + +// signatureCheckReader wraps an io.Reader from a LiteralData packet and hashes +// the data as it is read. When it sees an EOF from the underlying io.Reader +// it parses and checks a trailing Signature packet and triggers any MDC checks. +type signatureCheckReader struct { + packets *packet.Reader + h, wrappedHash hash.Hash + md *MessageDetails +} + +func (scr *signatureCheckReader) Read(buf []byte) (n int, err os.Error) { + n, err = scr.md.LiteralData.Body.Read(buf) + scr.wrappedHash.Write(buf[:n]) + if err == os.EOF { + var p packet.Packet + p, scr.md.SignatureError = scr.packets.Next() + if scr.md.SignatureError != nil { + return + } + + var ok bool + if scr.md.Signature, ok = p.(*packet.Signature); !ok { + scr.md.SignatureError = error.StructuralError("LiteralData not followed by Signature") + return + } + + scr.md.SignatureError = scr.md.SignedBy.PublicKey.VerifySignature(scr.h, scr.md.Signature) + + // The SymmetricallyEncrypted packet, if any, might have an + // unsigned hash of its own. In order to check this we need to + // close that Reader. + if scr.md.decrypted != nil { + mdcErr := scr.md.decrypted.Close() + if mdcErr != nil { + err = mdcErr + } + } + } + return +} + +// CheckDetachedSignature takes a signed file and a detached signature and +// returns the signer if the signature is valid. If the signer isn't know, +// UnknownIssuerError is returned. +func CheckDetachedSignature(keyring KeyRing, signed, signature io.Reader) (signer *Entity, err os.Error) { + p, err := packet.Read(signature) + if err != nil { + return + } + + sig, ok := p.(*packet.Signature) + if !ok { + return nil, error.StructuralError("non signature packet found") + } + + if sig.IssuerKeyId == nil { + return nil, error.StructuralError("signature doesn't have an issuer") + } + + keys := keyring.KeysById(*sig.IssuerKeyId) + if len(keys) == 0 { + return nil, error.UnknownIssuerError + } + + h, wrappedHash, err := hashForSignature(sig.Hash, sig.SigType) + if err != nil { + return + } + + _, err = io.Copy(wrappedHash, signed) + if err != nil && err != os.EOF { + return + } + + for _, key := range keys { + if key.SelfSignature.FlagsValid && !key.SelfSignature.FlagSign { + continue + } + err = key.PublicKey.VerifySignature(h, sig) + if err == nil { + return key.Entity, nil + } + } + + if err != nil { + return + } + + return nil, error.UnknownIssuerError +} + +// CheckArmoredDetachedSignature performs the same actions as +// CheckDetachedSignature but expects the signature to be armored. +func CheckArmoredDetachedSignature(keyring KeyRing, signed, signature io.Reader) (signer *Entity, err os.Error) { + body, err := readArmored(signature, SignatureType) + if err != nil { + return + } + + return CheckDetachedSignature(keyring, signed, body) +} diff --git a/src/pkg/crypto/openpgp/read_test.go b/src/pkg/crypto/openpgp/read_test.go new file mode 100644 index 000000000..4dc290ef2 --- /dev/null +++ b/src/pkg/crypto/openpgp/read_test.go @@ -0,0 +1,361 @@ +// 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 openpgp + +import ( + "bytes" + "crypto/openpgp/error" + "encoding/hex" + "io" + "io/ioutil" + "os" + "testing" +) + +func readerFromHex(s string) io.Reader { + data, err := hex.DecodeString(s) + if err != nil { + panic("readerFromHex: bad input") + } + return bytes.NewBuffer(data) +} + +func TestReadKeyRing(t *testing.T) { + kring, err := ReadKeyRing(readerFromHex(testKeys1And2Hex)) + if err != nil { + t.Error(err) + return + } + if len(kring) != 2 || uint32(kring[0].PrimaryKey.KeyId) != 0xC20C31BB || uint32(kring[1].PrimaryKey.KeyId) != 0x1E35246B { + t.Errorf("bad keyring: %#v", kring) + } +} + +func TestRereadKeyRing(t *testing.T) { + kring, err := ReadKeyRing(readerFromHex(testKeys1And2Hex)) + if err != nil { + t.Errorf("error in initial parse: %s", err) + return + } + out := new(bytes.Buffer) + err = kring[0].Serialize(out) + if err != nil { + t.Errorf("error in serialization: %s", err) + return + } + kring, err = ReadKeyRing(out) + if err != nil { + t.Errorf("error in second parse: %s", err) + return + } + + if len(kring) != 1 || uint32(kring[0].PrimaryKey.KeyId) != 0xC20C31BB { + t.Errorf("bad keyring: %#v", kring) + } +} + +func TestReadPrivateKeyRing(t *testing.T) { + kring, err := ReadKeyRing(readerFromHex(testKeys1And2PrivateHex)) + if err != nil { + t.Error(err) + return + } + if len(kring) != 2 || uint32(kring[0].PrimaryKey.KeyId) != 0xC20C31BB || uint32(kring[1].PrimaryKey.KeyId) != 0x1E35246B || kring[0].PrimaryKey == nil { + t.Errorf("bad keyring: %#v", kring) + } +} + +func TestReadDSAKey(t *testing.T) { + kring, err := ReadKeyRing(readerFromHex(dsaTestKeyHex)) + if err != nil { + t.Error(err) + return + } + if len(kring) != 1 || uint32(kring[0].PrimaryKey.KeyId) != 0x0CCC0360 { + t.Errorf("bad parse: %#v", kring) + } +} + +func TestGetKeyById(t *testing.T) { + kring, _ := ReadKeyRing(readerFromHex(testKeys1And2Hex)) + + keys := kring.KeysById(0xa34d7e18c20c31bb) + if len(keys) != 1 || keys[0].Entity != kring[0] { + t.Errorf("bad result for 0xa34d7e18c20c31bb: %#v", keys) + } + + keys = kring.KeysById(0xfd94408d4543314f) + if len(keys) != 1 || keys[0].Entity != kring[0] { + t.Errorf("bad result for 0xa34d7e18c20c31bb: %#v", keys) + } +} + +func checkSignedMessage(t *testing.T, signedHex, expected string) { + kring, _ := ReadKeyRing(readerFromHex(testKeys1And2Hex)) + + md, err := ReadMessage(readerFromHex(signedHex), kring, nil) + if err != nil { + t.Error(err) + return + } + + if !md.IsSigned || md.SignedByKeyId != 0xa34d7e18c20c31bb || md.SignedBy == nil || md.IsEncrypted || md.IsSymmetricallyEncrypted || len(md.EncryptedToKeyIds) != 0 || md.IsSymmetricallyEncrypted { + t.Errorf("bad MessageDetails: %#v", md) + } + + contents, err := ioutil.ReadAll(md.UnverifiedBody) + if err != nil { + t.Errorf("error reading UnverifiedBody: %s", err) + } + if string(contents) != expected { + t.Errorf("bad UnverifiedBody got:%s want:%s", string(contents), expected) + } + if md.SignatureError != nil || md.Signature == nil { + t.Errorf("failed to validate: %s", md.SignatureError) + } +} + +func TestSignedMessage(t *testing.T) { + checkSignedMessage(t, signedMessageHex, signedInput) +} + +func TestTextSignedMessage(t *testing.T) { + checkSignedMessage(t, signedTextMessageHex, signedTextInput) +} + +var signedEncryptedMessageTests = []struct { + keyRingHex string + messageHex string + signedByKeyId uint64 + encryptedToKeyId uint64 +}{ + { + testKeys1And2PrivateHex, + signedEncryptedMessageHex, + 0xa34d7e18c20c31bb, + 0x2a67d68660df41c7, + }, + { + dsaElGamalTestKeysHex, + signedEncryptedMessage2Hex, + 0x33af447ccd759b09, + 0xcf6a7abcd43e3673, + }, +} + +func TestSignedEncryptedMessage(t *testing.T) { + for i, test := range signedEncryptedMessageTests { + expected := "Signed and encrypted message\n" + kring, _ := ReadKeyRing(readerFromHex(test.keyRingHex)) + prompt := func(keys []Key, symmetric bool) ([]byte, os.Error) { + if symmetric { + t.Errorf("prompt: message was marked as symmetrically encrypted") + return nil, error.KeyIncorrectError + } + + if len(keys) == 0 { + t.Error("prompt: no keys requested") + return nil, error.KeyIncorrectError + } + + err := keys[0].PrivateKey.Decrypt([]byte("passphrase")) + if err != nil { + t.Errorf("prompt: error decrypting key: %s", err) + return nil, error.KeyIncorrectError + } + + return nil, nil + } + + md, err := ReadMessage(readerFromHex(test.messageHex), kring, prompt) + if err != nil { + t.Errorf("#%d: error reading message: %s", i, err) + return + } + + if !md.IsSigned || md.SignedByKeyId != test.signedByKeyId || md.SignedBy == nil || !md.IsEncrypted || md.IsSymmetricallyEncrypted || len(md.EncryptedToKeyIds) == 0 || md.EncryptedToKeyIds[0] != test.encryptedToKeyId { + t.Errorf("#%d: bad MessageDetails: %#v", i, md) + } + + contents, err := ioutil.ReadAll(md.UnverifiedBody) + if err != nil { + t.Errorf("#%d: error reading UnverifiedBody: %s", i, err) + } + if string(contents) != expected { + t.Errorf("#%d: bad UnverifiedBody got:%s want:%s", i, string(contents), expected) + } + + if md.SignatureError != nil || md.Signature == nil { + t.Errorf("#%d: failed to validate: %s", i, md.SignatureError) + } + } +} + +func TestUnspecifiedRecipient(t *testing.T) { + expected := "Recipient unspecified\n" + kring, _ := ReadKeyRing(readerFromHex(testKeys1And2PrivateHex)) + + md, err := ReadMessage(readerFromHex(recipientUnspecifiedHex), kring, nil) + if err != nil { + t.Errorf("error reading message: %s", err) + return + } + + contents, err := ioutil.ReadAll(md.UnverifiedBody) + if err != nil { + t.Errorf("error reading UnverifiedBody: %s", err) + } + if string(contents) != expected { + t.Errorf("bad UnverifiedBody got:%s want:%s", string(contents), expected) + } +} + +func TestSymmetricallyEncrypted(t *testing.T) { + expected := "Symmetrically encrypted.\n" + + prompt := func(keys []Key, symmetric bool) ([]byte, os.Error) { + if len(keys) != 0 { + t.Errorf("prompt: len(keys) = %d (want 0)", len(keys)) + } + + if !symmetric { + t.Errorf("symmetric is not set") + } + + return []byte("password"), nil + } + + md, err := ReadMessage(readerFromHex(symmetricallyEncryptedCompressedHex), nil, prompt) + if err != nil { + t.Errorf("ReadMessage: %s", err) + return + } + + contents, err := ioutil.ReadAll(md.UnverifiedBody) + if err != nil { + t.Errorf("ReadAll: %s", err) + } + + expectedCreationTime := uint32(1295992998) + if md.LiteralData.Time != expectedCreationTime { + t.Errorf("LiteralData.Time is %d, want %d", md.LiteralData.Time, expectedCreationTime) + } + + if string(contents) != expected { + t.Errorf("contents got: %s want: %s", string(contents), expected) + } +} + +func testDetachedSignature(t *testing.T, kring KeyRing, signature io.Reader, sigInput, tag string, expectedSignerKeyId uint64) { + signed := bytes.NewBufferString(sigInput) + signer, err := CheckDetachedSignature(kring, signed, signature) + if err != nil { + t.Errorf("%s: signature error: %s", tag, err) + return + } + if signer == nil { + t.Errorf("%s: signer is nil", tag) + return + } + if signer.PrimaryKey.KeyId != expectedSignerKeyId { + t.Errorf("%s: wrong signer got:%x want:%x", tag, signer.PrimaryKey.KeyId, expectedSignerKeyId) + } +} + +func TestDetachedSignature(t *testing.T) { + kring, _ := ReadKeyRing(readerFromHex(testKeys1And2Hex)) + testDetachedSignature(t, kring, readerFromHex(detachedSignatureHex), signedInput, "binary", testKey1KeyId) + testDetachedSignature(t, kring, readerFromHex(detachedSignatureTextHex), signedInput, "text", testKey1KeyId) +} + +func TestDetachedSignatureDSA(t *testing.T) { + kring, _ := ReadKeyRing(readerFromHex(dsaTestKeyHex)) + testDetachedSignature(t, kring, readerFromHex(detachedSignatureDSAHex), signedInput, "binary", testKey3KeyId) +} + +func TestReadingArmoredPrivateKey(t *testing.T) { + el, err := ReadArmoredKeyRing(bytes.NewBufferString(armoredPrivateKeyBlock)) + if err != nil { + t.Error(err) + } + if len(el) != 1 { + t.Errorf("got %d entities, wanted 1\n", len(el)) + } +} + +func TestNoArmoredData(t *testing.T) { + _, err := ReadArmoredKeyRing(bytes.NewBufferString("foo")) + if _, ok := err.(error.InvalidArgumentError); !ok { + t.Errorf("error was not an InvalidArgumentError: %s", err) + } +} + +const testKey1KeyId = 0xA34D7E18C20C31BB +const testKey3KeyId = 0x338934250CCC0360 + +const signedInput = "Signed message\nline 2\nline 3\n" +const signedTextInput = "Signed message\r\nline 2\r\nline 3\r\n" + +const recipientUnspecifiedHex = "848c0300000000000000000103ff62d4d578d03cf40c3da998dfe216c074fa6ddec5e31c197c9666ba292830d91d18716a80f699f9d897389a90e6d62d0238f5f07a5248073c0f24920e4bc4a30c2d17ee4e0cae7c3d4aaa4e8dced50e3010a80ee692175fa0385f62ecca4b56ee6e9980aa3ec51b61b077096ac9e800edaf161268593eedb6cc7027ff5cb32745d250010d407a6221ae22ef18469b444f2822478c4d190b24d36371a95cb40087cdd42d9399c3d06a53c0673349bfb607927f20d1e122bde1e2bf3aa6cae6edf489629bcaa0689539ae3b718914d88ededc3b" + +const detachedSignatureHex = "889c04000102000605024d449cd1000a0910a34d7e18c20c31bb167603ff57718d09f28a519fdc7b5a68b6a3336da04df85e38c5cd5d5bd2092fa4629848a33d85b1729402a2aab39c3ac19f9d573f773cc62c264dc924c067a79dfd8a863ae06c7c8686120760749f5fd9b1e03a64d20a7df3446ddc8f0aeadeaeba7cbaee5c1e366d65b6a0c6cc749bcb912d2f15013f812795c2e29eb7f7b77f39ce77" + +const detachedSignatureTextHex = "889c04010102000605024d449d21000a0910a34d7e18c20c31bbc8c60400a24fbef7342603a41cb1165767bd18985d015fb72fe05db42db36cfb2f1d455967f1e491194fbf6cf88146222b23bf6ffbd50d17598d976a0417d3192ff9cc0034fd00f287b02e90418bbefe609484b09231e4e7a5f3562e199bf39909ab5276c4d37382fe088f6b5c3426fc1052865da8b3ab158672d58b6264b10823dc4b39" + +const detachedSignatureDSAHex = "884604001102000605024d6c4eac000a0910338934250ccc0360f18d00a087d743d6405ed7b87755476629600b8b694a39e900a0abff8126f46faf1547c1743c37b21b4ea15b8f83" + +const testKeys1And2Hex = "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" + +const testKeys1And2PrivateHex = "9501d8044d3c5c10010400b1d13382944bd5aba23a4312968b5095d14f947f600eb478e14a6fcb16b0e0cac764884909c020bc495cfcc39a935387c661507bdb236a0612fb582cac3af9b29cc2c8c70090616c41b662f4da4c1201e195472eb7f4ae1ccbcbf9940fe21d985e379a5563dde5b9a23d35f1cfaa5790da3b79db26f23695107bfaca8e7b5bcd00110100010003ff4d91393b9a8e3430b14d6209df42f98dc927425b881f1209f319220841273a802a97c7bdb8b3a7740b3ab5866c4d1d308ad0d3a79bd1e883aacf1ac92dfe720285d10d08752a7efe3c609b1d00f17f2805b217be53999a7da7e493bfc3e9618fd17018991b8128aea70a05dbce30e4fbe626aa45775fa255dd9177aabf4df7cf0200c1ded12566e4bc2bb590455e5becfb2e2c9796482270a943343a7835de41080582c2be3caf5981aa838140e97afa40ad652a0b544f83eb1833b0957dce26e47b0200eacd6046741e9ce2ec5beb6fb5e6335457844fb09477f83b050a96be7da043e17f3a9523567ed40e7a521f818813a8b8a72209f1442844843ccc7eb9805442570200bdafe0438d97ac36e773c7162028d65844c4d463e2420aa2228c6e50dc2743c3d6c72d0d782a5173fe7be2169c8a9f4ef8a7cf3e37165e8c61b89c346cdc6c1799d2b41054657374204b6579203120285253412988b804130102002205024d3c5c10021b03060b090807030206150802090a0b0416020301021e01021780000a0910a34d7e18c20c31bbb5b304009cc45fe610b641a2c146331be94dade0a396e73ca725e1b25c21708d9cab46ecca5ccebc23055879df8f99eea39b377962a400f2ebdc36a7c99c333d74aeba346315137c3ff9d0a09b0273299090343048afb8107cf94cbd1400e3026f0ccac7ecebbc4d78588eb3e478fe2754d3ca664bcf3eac96ca4a6b0c8d7df5102f60f6b00200009d01d8044d3c5c10010400b201df61d67487301f11879d514f4248ade90c8f68c7af1284c161098de4c28c2850f1ec7b8e30f959793e571542ffc6532189409cb51c3d30dad78c4ad5165eda18b20d9826d8707d0f742e2ab492103a85bbd9ddf4f5720f6de7064feb0d39ee002219765bb07bcfb8b877f47abe270ddeda4f676108cecb6b9bb2ad484a4f00110100010003fd17a7490c22a79c59281fb7b20f5e6553ec0c1637ae382e8adaea295f50241037f8997cf42c1ce26417e015091451b15424b2c59eb8d4161b0975630408e394d3b00f88d4b4e18e2cc85e8251d4753a27c639c83f5ad4a571c4f19d7cd460b9b73c25ade730c99df09637bd173d8e3e981ac64432078263bb6dc30d3e974150dd0200d0ee05be3d4604d2146fb0457f31ba17c057560785aa804e8ca5530a7cd81d3440d0f4ba6851efcfd3954b7e68908fc0ba47f7ac37bf559c6c168b70d3a7c8cd0200da1c677c4bce06a068070f2b3733b0a714e88d62aa3f9a26c6f5216d48d5c2b5624144f3807c0df30be66b3268eeeca4df1fbded58faf49fc95dc3c35f134f8b01fd1396b6c0fc1b6c4f0eb8f5e44b8eace1e6073e20d0b8bc5385f86f1cf3f050f66af789f3ef1fc107b7f4421e19e0349c730c68f0a226981f4e889054fdb4dc149e8e889f04180102000905024d3c5c10021b0c000a0910a34d7e18c20c31bb1a03040085c8d62e16d05dc4e9dad64953c8a2eed8b6c12f92b1575eeaa6dcf7be9473dd5b24b37b6dffbb4e7c99ed1bd3cb11634be19b3e6e207bed7505c7ca111ccf47cb323bf1f8851eb6360e8034cbff8dd149993c959de89f8f77f38e7e98b8e3076323aa719328e2b408db5ec0d03936efd57422ba04f925cdc7b4c1af7590e40ab00200009501fe044d3c5c33010400b488c3e5f83f4d561f317817538d9d0397981e9aef1321ca68ebfae1cf8b7d388e19f4b5a24a82e2fbbf1c6c26557a6c5845307a03d815756f564ac7325b02bc83e87d5480a8fae848f07cb891f2d51ce7df83dcafdc12324517c86d472cc0ee10d47a68fd1d9ae49a6c19bbd36d82af597a0d88cc9c49de9df4e696fc1f0b5d0011010001fe030302e9030f3c783e14856063f16938530e148bc57a7aa3f3e4f90df9dceccdc779bc0835e1ad3d006e4a8d7b36d08b8e0de5a0d947254ecfbd22037e6572b426bcfdc517796b224b0036ff90bc574b5509bede85512f2eefb520fb4b02aa523ba739bff424a6fe81c5041f253f8d757e69a503d3563a104d0d49e9e890b9d0c26f96b55b743883b472caa7050c4acfd4a21f875bdf1258d88bd61224d303dc9df77f743137d51e6d5246b88c406780528fd9a3e15bab5452e5b93970d9dcc79f48b38651b9f15bfbcf6da452837e9cc70683d1bdca94507870f743e4ad902005812488dd342f836e72869afd00ce1850eea4cfa53ce10e3608e13d3c149394ee3cbd0e23d018fcbcb6e2ec5a1a22972d1d462ca05355d0d290dd2751e550d5efb38c6c89686344df64852bf4ff86638708f644e8ec6bd4af9b50d8541cb91891a431326ab2e332faa7ae86cfb6e0540aa63160c1e5cdd5a4add518b303fff0a20117c6bc77f7cfbaf36b04c865c6c2b42754657374204b6579203220285253412c20656e637279707465642070726976617465206b65792988b804130102002205024d3c5c33021b03060b090807030206150802090a0b0416020301021e01021780000a0910d4984f961e35246b98940400908a73b6a6169f700434f076c6c79015a49bee37130eaf23aaa3cfa9ce60bfe4acaa7bc95f1146ada5867e0079babb38804891f4f0b8ebca57a86b249dee786161a755b7a342e68ccf3f78ed6440a93a6626beb9a37aa66afcd4f888790cb4bb46d94a4ae3eb3d7d3e6b00f6bfec940303e89ec5b32a1eaaacce66497d539328b00200009d01fe044d3c5c33010400a4e913f9442abcc7f1804ccab27d2f787ffa592077ca935a8bb23165bd8d57576acac647cc596b2c3f814518cc8c82953c7a4478f32e0cf645630a5ba38d9618ef2bc3add69d459ae3dece5cab778938d988239f8c5ae437807075e06c828019959c644ff05ef6a5a1dab72227c98e3a040b0cf219026640698d7a13d8538a570011010001fe030302e9030f3c783e148560f936097339ae381d63116efcf802ff8b1c9360767db5219cc987375702a4123fd8657d3e22700f23f95020d1b261eda5257e9a72f9a918e8ef22dd5b3323ae03bbc1923dd224db988cadc16acc04b120a9f8b7e84da9716c53e0334d7b66586ddb9014df604b41be1e960dcfcbc96f4ed150a1a0dd070b9eb14276b9b6be413a769a75b519a53d3ecc0c220e85cd91ca354d57e7344517e64b43b6e29823cbd87eae26e2b2e78e6dedfbb76e3e9f77bcb844f9a8932eb3db2c3f9e44316e6f5d60e9e2a56e46b72abe6b06dc9a31cc63f10023d1f5e12d2a3ee93b675c96f504af0001220991c88db759e231b3320dcedf814dcf723fd9857e3d72d66a0f2af26950b915abdf56c1596f46a325bf17ad4810d3535fb02a259b247ac3dbd4cc3ecf9c51b6c07cebb009c1506fba0a89321ec8683e3fd009a6e551d50243e2d5092fefb3321083a4bad91320dc624bd6b5dddf93553e3d53924c05bfebec1fb4bd47e89a1a889f04180102000905024d3c5c33021b0c000a0910d4984f961e35246b26c703ff7ee29ef53bc1ae1ead533c408fa136db508434e233d6e62be621e031e5940bbd4c08142aed0f82217e7c3e1ec8de574bc06ccf3c36633be41ad78a9eacd209f861cae7b064100758545cc9dd83db71806dc1cfd5fb9ae5c7474bba0c19c44034ae61bae5eca379383339dece94ff56ff7aa44a582f3e5c38f45763af577c0934b0020000" + +const dsaElGamalTestKeysHex = "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" + +const signedMessageHex = "a3019bc0cbccc0c4b8d8b74ee2108fe16ec6d3ca490cbe362d3f8333d3f352531472538b8b13d353b97232f352158c20943157c71c16064626063656269052062e4e01987e9b6fccff4b7df3a34c534b23e679cbec3bc0f8f6e64dfb4b55fe3f8efa9ce110ddb5cd79faf1d753c51aecfa669f7e7aa043436596cccc3359cb7dd6bbe9ecaa69e5989d9e57209571edc0b2fa7f57b9b79a64ee6e99ce1371395fee92fec2796f7b15a77c386ff668ee27f6d38f0baa6c438b561657377bf6acff3c5947befd7bf4c196252f1d6e5c524d0300" + +const signedTextMessageHex = "a3019bc0cbccc8c4b8d8b74ee2108fe16ec6d36a250cbece0c178233d3f352531472538b8b13d35379b97232f352158ca0b4312f57c71c1646462606365626906a062e4e019811591798ff99bf8afee860b0d8a8c2a85c3387e3bcf0bb3b17987f2bbcfab2aa526d930cbfd3d98757184df3995c9f3e7790e36e3e9779f06089d4c64e9e47dd6202cb6e9bc73c5d11bb59fbaf89d22d8dc7cf199ddf17af96e77c5f65f9bbed56f427bd8db7af37f6c9984bf9385efaf5f184f986fb3e6adb0ecfe35bbf92d16a7aa2a344fb0bc52fb7624f0200" + +const signedEncryptedMessageHex = "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" + +const signedEncryptedMessage2Hex = "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" + +const symmetricallyEncryptedCompressedHex = "8c0d04030302eb4a03808145d0d260c92f714339e13de5a79881216431925bf67ee2898ea61815f07894cd0703c50d0a76ef64d482196f47a8bc729af9b80bb6" + +const dsaTestKeyHex = "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" + +const dsaTestKeyPrivateHex = "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" + +const armoredPrivateKeyBlock = `-----BEGIN PGP PRIVATE KEY BLOCK----- +Version: GnuPG v1.4.10 (GNU/Linux) + +lQHYBE2rFNoBBADFwqWQIW/DSqcB4yCQqnAFTJ27qS5AnB46ccAdw3u4Greeu3Bp +idpoHdjULy7zSKlwR1EA873dO/k/e11Ml3dlAFUinWeejWaK2ugFP6JjiieSsrKn +vWNicdCS4HTWn0X4sjl0ZiAygw6GNhqEQ3cpLeL0g8E9hnYzJKQ0LWJa0QARAQAB +AAP/TB81EIo2VYNmTq0pK1ZXwUpxCrvAAIG3hwKjEzHcbQznsjNvPUihZ+NZQ6+X +0HCfPAdPkGDCLCb6NavcSW+iNnLTrdDnSI6+3BbIONqWWdRDYJhqZCkqmG6zqSfL +IdkJgCw94taUg5BWP/AAeQrhzjChvpMQTVKQL5mnuZbUCeMCAN5qrYMP2S9iKdnk +VANIFj7656ARKt/nf4CBzxcpHTyB8+d2CtPDKCmlJP6vL8t58Jmih+kHJMvC0dzn +gr5f5+sCAOOe5gt9e0am7AvQWhdbHVfJU0TQJx+m2OiCJAqGTB1nvtBLHdJnfdC9 +TnXXQ6ZXibqLyBies/xeY2sCKL5qtTMCAKnX9+9d/5yQxRyrQUHt1NYhaXZnJbHx +q4ytu0eWz+5i68IYUSK69jJ1NWPM0T6SkqpB3KCAIv68VFm9PxqG1KmhSrQIVGVz +dCBLZXmIuAQTAQIAIgUCTasU2gIbAwYLCQgHAwIGFQgCCQoLBBYCAwECHgECF4AA +CgkQO9o98PRieSoLhgQAkLEZex02Qt7vGhZzMwuN0R22w3VwyYyjBx+fM3JFETy1 +ut4xcLJoJfIaF5ZS38UplgakHG0FQ+b49i8dMij0aZmDqGxrew1m4kBfjXw9B/v+ +eIqpODryb6cOSwyQFH0lQkXC040pjq9YqDsO5w0WYNXYKDnzRV0p4H1pweo2VDid +AdgETasU2gEEAN46UPeWRqKHvA99arOxee38fBt2CI08iiWyI8T3J6ivtFGixSqV +bRcPxYO/qLpVe5l84Nb3X71GfVXlc9hyv7CD6tcowL59hg1E/DC5ydI8K8iEpUmK +/UnHdIY5h8/kqgGxkY/T/hgp5fRQgW1ZoZxLajVlMRZ8W4tFtT0DeA+JABEBAAEA +A/0bE1jaaZKj6ndqcw86jd+QtD1SF+Cf21CWRNeLKnUds4FRRvclzTyUMuWPkUeX +TaNNsUOFqBsf6QQ2oHUBBK4VCHffHCW4ZEX2cd6umz7mpHW6XzN4DECEzOVksXtc +lUC1j4UB91DC/RNQqwX1IV2QLSwssVotPMPqhOi0ZLNY7wIA3n7DWKInxYZZ4K+6 +rQ+POsz6brEoRHwr8x6XlHenq1Oki855pSa1yXIARoTrSJkBtn5oI+f8AzrnN0BN +oyeQAwIA/7E++3HDi5aweWrViiul9cd3rcsS0dEnksPhvS0ozCJiHsq/6GFmy7J8 +QSHZPteedBnZyNp5jR+H7cIfVN3KgwH/Skq4PsuPhDq5TKK6i8Pc1WW8MA6DXTdU +nLkX7RGmMwjC0DBf7KWAlPjFaONAX3a8ndnz//fy1q7u2l9AZwrj1qa1iJ8EGAEC +AAkFAk2rFNoCGwwACgkQO9o98PRieSo2/QP/WTzr4ioINVsvN1akKuekmEMI3LAp +BfHwatufxxP1U+3Si/6YIk7kuPB9Hs+pRqCXzbvPRrI8NHZBmc8qIGthishdCYad +AHcVnXjtxrULkQFGbGvhKURLvS9WnzD/m1K2zzwxzkPTzT9/Yf06O6Mal5AdugPL +VrM0m72/jnpKo04= +=zNCn +-----END PGP PRIVATE KEY BLOCK-----` diff --git a/src/pkg/crypto/openpgp/s2k/Makefile b/src/pkg/crypto/openpgp/s2k/Makefile new file mode 100644 index 000000000..731d53431 --- /dev/null +++ b/src/pkg/crypto/openpgp/s2k/Makefile @@ -0,0 +1,11 @@ +# 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/s2k +GOFILES=\ + s2k.go\ + +include ../../../../Make.pkg diff --git a/src/pkg/crypto/openpgp/s2k/s2k.go b/src/pkg/crypto/openpgp/s2k/s2k.go new file mode 100644 index 000000000..da926a76e --- /dev/null +++ b/src/pkg/crypto/openpgp/s2k/s2k.go @@ -0,0 +1,180 @@ +// 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 s2k implements the various OpenPGP string-to-key transforms as +// specified in RFC 4800 section 3.7.1. +package s2k + +import ( + "crypto" + "crypto/openpgp/error" + "hash" + "io" + "os" + "strconv" +) + +// Simple writes to out the result of computing the Simple S2K function (RFC +// 4880, section 3.7.1.1) using the given hash and input passphrase. +func Simple(out []byte, h hash.Hash, in []byte) { + Salted(out, h, in, nil) +} + +var zero [1]byte + +// Salted writes to out the result of computing the Salted S2K function (RFC +// 4880, section 3.7.1.2) using the given hash, input passphrase and salt. +func Salted(out []byte, h hash.Hash, in []byte, salt []byte) { + done := 0 + + for i := 0; done < len(out); i++ { + h.Reset() + for j := 0; j < i; j++ { + h.Write(zero[:]) + } + h.Write(salt) + h.Write(in) + n := copy(out[done:], h.Sum()) + done += n + } +} + +// Iterated writes to out the result of computing the Iterated and Salted S2K +// function (RFC 4880, section 3.7.1.3) using the given hash, input passphrase, +// salt and iteration count. +func Iterated(out []byte, h hash.Hash, in []byte, salt []byte, count int) { + combined := make([]byte, len(in)+len(salt)) + copy(combined, salt) + copy(combined[len(salt):], in) + + if count < len(combined) { + count = len(combined) + } + + done := 0 + for i := 0; done < len(out); i++ { + h.Reset() + for j := 0; j < i; j++ { + h.Write(zero[:]) + } + written := 0 + for written < count { + if written+len(combined) > count { + todo := count - written + h.Write(combined[:todo]) + written = count + } else { + h.Write(combined) + written += len(combined) + } + } + n := copy(out[done:], h.Sum()) + done += n + } +} + +// Parse reads a binary specification for a string-to-key transformation from r +// and returns a function which performs that transform. +func Parse(r io.Reader) (f func(out, in []byte), err os.Error) { + var buf [9]byte + + _, err = io.ReadFull(r, buf[:2]) + if err != nil { + return + } + + hash, ok := HashIdToHash(buf[1]) + if !ok { + return nil, error.UnsupportedError("hash for S2K function: " + strconv.Itoa(int(buf[1]))) + } + h := hash.New() + if h == nil { + return nil, error.UnsupportedError("hash not available: " + strconv.Itoa(int(hash))) + } + + switch buf[0] { + case 1: + f := func(out, in []byte) { + Simple(out, h, in) + } + return f, nil + case 2: + _, err := io.ReadFull(r, buf[:8]) + if err != nil { + return + } + f := func(out, in []byte) { + Salted(out, h, in, buf[:8]) + } + return f, nil + case 3: + _, err := io.ReadFull(r, buf[:9]) + if err != nil { + return + } + count := (16 + int(buf[8]&15)) << (uint32(buf[8]>>4) + 6) + f := func(out, in []byte) { + Iterated(out, h, in, buf[:8], count) + } + return f, nil + } + + return nil, error.UnsupportedError("S2K function") +} + +// Serialize salts and stretches the given passphrase and writes the resulting +// key into key. It also serializes an S2K descriptor to w. +func Serialize(w io.Writer, key []byte, rand io.Reader, passphrase []byte) os.Error { + var buf [11]byte + buf[0] = 3 /* iterated and salted */ + buf[1], _ = HashToHashId(crypto.SHA1) + salt := buf[2:10] + if _, err := io.ReadFull(rand, salt); err != nil { + return err + } + const count = 65536 // this is the default in gpg + buf[10] = 96 // 65536 iterations + if _, err := w.Write(buf[:]); err != nil { + return err + } + + Iterated(key, crypto.SHA1.New(), passphrase, salt, count) + return nil +} + +// hashToHashIdMapping contains pairs relating OpenPGP's hash identifier with +// Go's crypto.Hash type. See RFC 4880, section 9.4. +var hashToHashIdMapping = []struct { + id byte + hash crypto.Hash +}{ + {1, crypto.MD5}, + {2, crypto.SHA1}, + {3, crypto.RIPEMD160}, + {8, crypto.SHA256}, + {9, crypto.SHA384}, + {10, crypto.SHA512}, + {11, crypto.SHA224}, +} + +// HashIdToHash returns a crypto.Hash which corresponds to the given OpenPGP +// hash id. +func HashIdToHash(id byte) (h crypto.Hash, ok bool) { + for _, m := range hashToHashIdMapping { + if m.id == id { + return m.hash, true + } + } + return 0, false +} + +// HashIdToHash returns an OpenPGP hash id which corresponds the given Hash. +func HashToHashId(h crypto.Hash) (id byte, ok bool) { + for _, m := range hashToHashIdMapping { + if m.hash == h { + return m.id, true + } + } + return 0, false +} diff --git a/src/pkg/crypto/openpgp/s2k/s2k_test.go b/src/pkg/crypto/openpgp/s2k/s2k_test.go new file mode 100644 index 000000000..ec4012c23 --- /dev/null +++ b/src/pkg/crypto/openpgp/s2k/s2k_test.go @@ -0,0 +1,118 @@ +// 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 s2k + +import ( + "bytes" + "crypto/sha1" + "crypto/rand" + "encoding/hex" + "testing" +) + +var saltedTests = []struct { + in, out string +}{ + {"hello", "10295ac1"}, + {"world", "ac587a5e"}, + {"foo", "4dda8077"}, + {"bar", "bd8aac6b9ea9cae04eae6a91c6133b58b5d9a61c14f355516ed9370456"}, + {"x", "f1d3f289"}, + {"xxxxxxxxxxxxxxxxxxxxxxx", "e00d7b45"}, +} + +func TestSalted(t *testing.T) { + h := sha1.New() + salt := [4]byte{1, 2, 3, 4} + + for i, test := range saltedTests { + expected, _ := hex.DecodeString(test.out) + out := make([]byte, len(expected)) + Salted(out, h, []byte(test.in), salt[:]) + if !bytes.Equal(expected, out) { + t.Errorf("#%d, got: %x want: %x", i, out, expected) + } + } +} + +var iteratedTests = []struct { + in, out string +}{ + {"hello", "83126105"}, + {"world", "6fa317f9"}, + {"foo", "8fbc35b9"}, + {"bar", "2af5a99b54f093789fd657f19bd245af7604d0f6ae06f66602a46a08ae"}, + {"x", "5a684dfe"}, + {"xxxxxxxxxxxxxxxxxxxxxxx", "18955174"}, +} + +func TestIterated(t *testing.T) { + h := sha1.New() + salt := [4]byte{4, 3, 2, 1} + + for i, test := range iteratedTests { + expected, _ := hex.DecodeString(test.out) + out := make([]byte, len(expected)) + Iterated(out, h, []byte(test.in), salt[:], 31) + if !bytes.Equal(expected, out) { + t.Errorf("#%d, got: %x want: %x", i, out, expected) + } + } +} + +var parseTests = []struct { + spec, in, out string +}{ + /* Simple with SHA1 */ + {"0102", "hello", "aaf4c61d"}, + /* Salted with SHA1 */ + {"02020102030405060708", "hello", "f4f7d67e"}, + /* Iterated with SHA1 */ + {"03020102030405060708f1", "hello", "f2a57b7c"}, +} + +func TestParse(t *testing.T) { + for i, test := range parseTests { + spec, _ := hex.DecodeString(test.spec) + buf := bytes.NewBuffer(spec) + f, err := Parse(buf) + if err != nil { + t.Errorf("%d: Parse returned error: %s", i, err) + continue + } + + expected, _ := hex.DecodeString(test.out) + out := make([]byte, len(expected)) + f(out, []byte(test.in)) + if !bytes.Equal(out, expected) { + t.Errorf("%d: output got: %x want: %x", i, out, expected) + } + if testing.Short() { + break + } + } +} + +func TestSerialize(t *testing.T) { + buf := bytes.NewBuffer(nil) + key := make([]byte, 16) + passphrase := []byte("testing") + err := Serialize(buf, key, rand.Reader, passphrase) + if err != nil { + t.Errorf("failed to serialize: %s", err) + return + } + + f, err := Parse(buf) + if err != nil { + t.Errorf("failed to reparse: %s", err) + return + } + key2 := make([]byte, len(key)) + f(key2, passphrase) + if !bytes.Equal(key2, key) { + t.Errorf("keys don't match: %x (serialied) vs %x (parsed)", key, key2) + } +} diff --git a/src/pkg/crypto/openpgp/write.go b/src/pkg/crypto/openpgp/write.go new file mode 100644 index 000000000..9884472ce --- /dev/null +++ b/src/pkg/crypto/openpgp/write.go @@ -0,0 +1,308 @@ +// 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 openpgp + +import ( + "crypto" + "crypto/openpgp/armor" + "crypto/openpgp/error" + "crypto/openpgp/packet" + "crypto/openpgp/s2k" + "crypto/rand" + _ "crypto/sha256" + "hash" + "io" + "os" + "strconv" + "time" +) + +// DetachSign signs message with the private key from signer (which must +// already have been decrypted) and writes the signature to w. +func DetachSign(w io.Writer, signer *Entity, message io.Reader) os.Error { + return detachSign(w, signer, message, packet.SigTypeBinary) +} + +// ArmoredDetachSign signs message with the private key from signer (which +// must already have been decrypted) and writes an armored signature to w. +func ArmoredDetachSign(w io.Writer, signer *Entity, message io.Reader) (err os.Error) { + return armoredDetachSign(w, signer, message, packet.SigTypeBinary) +} + +// DetachSignText signs message (after canonicalising the line endings) with +// the private key from signer (which must already have been decrypted) and +// writes the signature to w. +func DetachSignText(w io.Writer, signer *Entity, message io.Reader) os.Error { + return detachSign(w, signer, message, packet.SigTypeText) +} + +// ArmoredDetachSignText signs message (after canonicalising the line endings) +// with the private key from signer (which must already have been decrypted) +// and writes an armored signature to w. +func ArmoredDetachSignText(w io.Writer, signer *Entity, message io.Reader) os.Error { + return armoredDetachSign(w, signer, message, packet.SigTypeText) +} + +func armoredDetachSign(w io.Writer, signer *Entity, message io.Reader, sigType packet.SignatureType) (err os.Error) { + out, err := armor.Encode(w, SignatureType, nil) + if err != nil { + return + } + err = detachSign(out, signer, message, sigType) + if err != nil { + return + } + return out.Close() +} + +func detachSign(w io.Writer, signer *Entity, message io.Reader, sigType packet.SignatureType) (err os.Error) { + if signer.PrivateKey == nil { + return error.InvalidArgumentError("signing key doesn't have a private key") + } + if signer.PrivateKey.Encrypted { + return error.InvalidArgumentError("signing key is encrypted") + } + + sig := new(packet.Signature) + sig.SigType = sigType + sig.PubKeyAlgo = signer.PrivateKey.PubKeyAlgo + sig.Hash = crypto.SHA256 + sig.CreationTime = uint32(time.Seconds()) + sig.IssuerKeyId = &signer.PrivateKey.KeyId + + h, wrappedHash, err := hashForSignature(sig.Hash, sig.SigType) + if err != nil { + return + } + io.Copy(wrappedHash, message) + + err = sig.Sign(h, signer.PrivateKey) + if err != nil { + return + } + + return sig.Serialize(w) +} + +// FileHints contains metadata about encrypted files. This metadata is, itself, +// encrypted. +type FileHints struct { + // IsBinary can be set to hint that the contents are binary data. + IsBinary bool + // FileName hints at the name of the file that should be written. It's + // truncated to 255 bytes if longer. It may be empty to suggest that the + // file should not be written to disk. It may be equal to "_CONSOLE" to + // suggest the data should not be written to disk. + FileName string + // EpochSeconds contains the modification time of the file, or 0 if not applicable. + EpochSeconds uint32 +} + +// SymmetricallyEncrypt acts like gpg -c: it encrypts a file with a passphrase. +// The resulting WriteCloser must be closed after the contents of the file have +// been written. +func SymmetricallyEncrypt(ciphertext io.Writer, passphrase []byte, hints *FileHints) (plaintext io.WriteCloser, err os.Error) { + if hints == nil { + hints = &FileHints{} + } + + key, err := packet.SerializeSymmetricKeyEncrypted(ciphertext, rand.Reader, passphrase, packet.CipherAES128) + if err != nil { + return + } + w, err := packet.SerializeSymmetricallyEncrypted(ciphertext, packet.CipherAES128, key) + if err != nil { + return + } + return packet.SerializeLiteral(w, hints.IsBinary, hints.FileName, hints.EpochSeconds) +} + +// intersectPreferences mutates and returns a prefix of a that contains only +// the values in the intersection of a and b. The order of a is preserved. +func intersectPreferences(a []uint8, b []uint8) (intersection []uint8) { + var j int + for _, v := range a { + for _, v2 := range b { + if v == v2 { + a[j] = v + j++ + break + } + } + } + + return a[:j] +} + +func hashToHashId(h crypto.Hash) uint8 { + v, ok := s2k.HashToHashId(h) + if !ok { + panic("tried to convert unknown hash") + } + return v +} + +// Encrypt encrypts a message to a number of recipients and, optionally, signs +// it. hints contains optional information, that is also encrypted, that aids +// the recipients in processing the message. The resulting WriteCloser must +// be closed after the contents of the file have been written. +func Encrypt(ciphertext io.Writer, to []*Entity, signed *Entity, hints *FileHints) (plaintext io.WriteCloser, err os.Error) { + var signer *packet.PrivateKey + if signed != nil { + signer = signed.signingKey().PrivateKey + if signer == nil || signer.Encrypted { + return nil, error.InvalidArgumentError("signing key must be decrypted") + } + } + + // These are the possible ciphers that we'll use for the message. + candidateCiphers := []uint8{ + uint8(packet.CipherAES128), + uint8(packet.CipherAES256), + uint8(packet.CipherCAST5), + } + // These are the possible hash functions that we'll use for the signature. + candidateHashes := []uint8{ + hashToHashId(crypto.SHA256), + hashToHashId(crypto.SHA512), + hashToHashId(crypto.SHA1), + hashToHashId(crypto.RIPEMD160), + } + // In the event that a recipient doesn't specify any supported ciphers + // or hash functions, these are the ones that we assume that every + // implementation supports. + defaultCiphers := candidateCiphers[len(candidateCiphers)-1:] + defaultHashes := candidateHashes[len(candidateHashes)-1:] + + encryptKeys := make([]Key, len(to)) + for i := range to { + encryptKeys[i] = to[i].encryptionKey() + if encryptKeys[i].PublicKey == nil { + return nil, error.InvalidArgumentError("cannot encrypt a message to key id " + strconv.Uitob64(to[i].PrimaryKey.KeyId, 16) + " because it has no encryption keys") + } + + sig := to[i].primaryIdentity().SelfSignature + + preferredSymmetric := sig.PreferredSymmetric + if len(preferredSymmetric) == 0 { + preferredSymmetric = defaultCiphers + } + preferredHashes := sig.PreferredHash + if len(preferredHashes) == 0 { + preferredHashes = defaultHashes + } + candidateCiphers = intersectPreferences(candidateCiphers, preferredSymmetric) + candidateHashes = intersectPreferences(candidateHashes, preferredHashes) + } + + if len(candidateCiphers) == 0 || len(candidateHashes) == 0 { + return nil, error.InvalidArgumentError("cannot encrypt because recipient set shares no common algorithms") + } + + cipher := packet.CipherFunction(candidateCiphers[0]) + hash, _ := s2k.HashIdToHash(candidateHashes[0]) + symKey := make([]byte, cipher.KeySize()) + if _, err := io.ReadFull(rand.Reader, symKey); err != nil { + return nil, err + } + + for _, key := range encryptKeys { + if err := packet.SerializeEncryptedKey(ciphertext, rand.Reader, key.PublicKey, cipher, symKey); err != nil { + return nil, err + } + } + + encryptedData, err := packet.SerializeSymmetricallyEncrypted(ciphertext, cipher, symKey) + if err != nil { + return + } + + if signer != nil { + ops := &packet.OnePassSignature{ + SigType: packet.SigTypeBinary, + Hash: hash, + PubKeyAlgo: signer.PubKeyAlgo, + KeyId: signer.KeyId, + IsLast: true, + } + if err := ops.Serialize(encryptedData); err != nil { + return nil, err + } + } + + if hints == nil { + hints = &FileHints{} + } + + w := encryptedData + if signer != nil { + // If we need to write a signature packet after the literal + // data then we need to stop literalData from closing + // encryptedData. + w = noOpCloser{encryptedData} + + } + literalData, err := packet.SerializeLiteral(w, hints.IsBinary, hints.FileName, hints.EpochSeconds) + if err != nil { + return nil, err + } + + if signer != nil { + return signatureWriter{encryptedData, literalData, hash, hash.New(), signer}, nil + } + return literalData, nil +} + +// signatureWriter hashes the contents of a message while passing it along to +// literalData. When closed, it closes literalData, writes a signature packet +// to encryptedData and then also closes encryptedData. +type signatureWriter struct { + encryptedData io.WriteCloser + literalData io.WriteCloser + hashType crypto.Hash + h hash.Hash + signer *packet.PrivateKey +} + +func (s signatureWriter) Write(data []byte) (int, os.Error) { + s.h.Write(data) + return s.literalData.Write(data) +} + +func (s signatureWriter) Close() os.Error { + sig := &packet.Signature{ + SigType: packet.SigTypeBinary, + PubKeyAlgo: s.signer.PubKeyAlgo, + Hash: s.hashType, + CreationTime: uint32(time.Seconds()), + IssuerKeyId: &s.signer.KeyId, + } + + if err := sig.Sign(s.h, s.signer); err != nil { + return err + } + if err := s.literalData.Close(); err != nil { + return err + } + if err := sig.Serialize(s.encryptedData); err != nil { + return err + } + return s.encryptedData.Close() +} + +// noOpCloser is like an ioutil.NopCloser, but for an io.Writer. +// TODO: we have two of these in OpenPGP packages alone. This probably needs +// to be promoted somewhere more common. +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 +} diff --git a/src/pkg/crypto/openpgp/write_test.go b/src/pkg/crypto/openpgp/write_test.go new file mode 100644 index 000000000..c542dfa45 --- /dev/null +++ b/src/pkg/crypto/openpgp/write_test.go @@ -0,0 +1,233 @@ +// 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 openpgp + +import ( + "bytes" + "crypto/rand" + "os" + "io" + "io/ioutil" + "testing" + "time" +) + +func TestSignDetached(t *testing.T) { + kring, _ := ReadKeyRing(readerFromHex(testKeys1And2PrivateHex)) + out := bytes.NewBuffer(nil) + message := bytes.NewBufferString(signedInput) + err := DetachSign(out, kring[0], message) + if err != nil { + t.Error(err) + } + + testDetachedSignature(t, kring, out, signedInput, "check", testKey1KeyId) +} + +func TestSignTextDetached(t *testing.T) { + kring, _ := ReadKeyRing(readerFromHex(testKeys1And2PrivateHex)) + out := bytes.NewBuffer(nil) + message := bytes.NewBufferString(signedInput) + err := DetachSignText(out, kring[0], message) + if err != nil { + t.Error(err) + } + + testDetachedSignature(t, kring, out, signedInput, "check", testKey1KeyId) +} + +func TestSignDetachedDSA(t *testing.T) { + kring, _ := ReadKeyRing(readerFromHex(dsaTestKeyPrivateHex)) + out := bytes.NewBuffer(nil) + message := bytes.NewBufferString(signedInput) + err := DetachSign(out, kring[0], message) + if err != nil { + t.Error(err) + } + + testDetachedSignature(t, kring, out, signedInput, "check", testKey3KeyId) +} + +func TestNewEntity(t *testing.T) { + if testing.Short() { + return + } + + e, err := NewEntity(rand.Reader, time.Seconds(), "Test User", "test", "test@example.com") + if err != nil { + t.Errorf("failed to create entity: %s", err) + return + } + + w := bytes.NewBuffer(nil) + if err := e.SerializePrivate(w); err != nil { + t.Errorf("failed to serialize entity: %s", err) + return + } + serialized := w.Bytes() + + el, err := ReadKeyRing(w) + if err != nil { + t.Errorf("failed to reparse entity: %s", err) + return + } + + if len(el) != 1 { + t.Errorf("wrong number of entities found, got %d, want 1", len(el)) + } + + w = bytes.NewBuffer(nil) + if err := e.SerializePrivate(w); err != nil { + t.Errorf("failed to serialize entity second time: %s", err) + return + } + + if !bytes.Equal(w.Bytes(), serialized) { + t.Errorf("results differed") + } +} + +func TestSymmetricEncryption(t *testing.T) { + buf := new(bytes.Buffer) + plaintext, err := SymmetricallyEncrypt(buf, []byte("testing"), nil) + if err != nil { + t.Errorf("error writing headers: %s", err) + return + } + message := []byte("hello world\n") + _, err = plaintext.Write(message) + if err != nil { + t.Errorf("error writing to plaintext writer: %s", err) + } + err = plaintext.Close() + if err != nil { + t.Errorf("error closing plaintext writer: %s", err) + } + + md, err := ReadMessage(buf, nil, func(keys []Key, symmetric bool) ([]byte, os.Error) { + return []byte("testing"), nil + }) + if err != nil { + t.Errorf("error rereading message: %s", err) + } + messageBuf := bytes.NewBuffer(nil) + _, err = io.Copy(messageBuf, md.UnverifiedBody) + if err != nil { + t.Errorf("error rereading message: %s", err) + } + if !bytes.Equal(message, messageBuf.Bytes()) { + t.Errorf("recovered message incorrect got '%s', want '%s'", messageBuf.Bytes(), message) + } +} + +var testEncryptionTests = []struct { + keyRingHex string + isSigned bool +}{ + { + testKeys1And2PrivateHex, + false, + }, + { + testKeys1And2PrivateHex, + true, + }, + { + dsaElGamalTestKeysHex, + false, + }, + { + dsaElGamalTestKeysHex, + true, + }, +} + +func TestEncryption(t *testing.T) { + for i, test := range testEncryptionTests { + kring, _ := ReadKeyRing(readerFromHex(test.keyRingHex)) + + passphrase := []byte("passphrase") + for _, entity := range kring { + if entity.PrivateKey != nil && entity.PrivateKey.Encrypted { + err := entity.PrivateKey.Decrypt(passphrase) + if err != nil { + t.Errorf("#%d: failed to decrypt key", i) + } + } + for _, subkey := range entity.Subkeys { + if subkey.PrivateKey != nil && subkey.PrivateKey.Encrypted { + err := subkey.PrivateKey.Decrypt(passphrase) + if err != nil { + t.Errorf("#%d: failed to decrypt subkey", i) + } + } + } + } + + var signed *Entity + if test.isSigned { + signed = kring[0] + } + + buf := new(bytes.Buffer) + w, err := Encrypt(buf, kring[:1], signed, nil /* no hints */ ) + if err != nil { + t.Errorf("#%d: error in Encrypt: %s", i, err) + continue + } + + const message = "testing" + _, err = w.Write([]byte(message)) + if err != nil { + t.Errorf("#%d: error writing plaintext: %s", i, err) + continue + } + err = w.Close() + if err != nil { + t.Errorf("#%d: error closing WriteCloser: %s", i, err) + continue + } + + md, err := ReadMessage(buf, kring, nil /* no prompt */ ) + if err != nil { + t.Errorf("#%d: error reading message: %s", i, err) + continue + } + + if test.isSigned { + expectedKeyId := kring[0].signingKey().PublicKey.KeyId + if md.SignedByKeyId != expectedKeyId { + t.Errorf("#%d: message signed by wrong key id, got: %d, want: %d", i, *md.SignedBy, expectedKeyId) + } + if md.SignedBy == nil { + t.Errorf("#%d: failed to find the signing Entity", i) + } + } + + plaintext, err := ioutil.ReadAll(md.UnverifiedBody) + if err != nil { + t.Errorf("#%d: error reading encrypted contents: %s", i, err) + continue + } + + expectedKeyId := kring[0].encryptionKey().PublicKey.KeyId + if len(md.EncryptedToKeyIds) != 1 || md.EncryptedToKeyIds[0] != expectedKeyId { + t.Errorf("#%d: expected message to be encrypted to %v, but got %#v", i, expectedKeyId, md.EncryptedToKeyIds) + } + + if string(plaintext) != message { + t.Errorf("#%d: got: %s, want: %s", i, string(plaintext), message) + } + + if test.isSigned { + if md.SignatureError != nil { + t.Errorf("#%d: signature error: %s", i, err) + } + if md.Signature == nil { + t.Error("signature missing") + } + } + } +} |