diff options
Diffstat (limited to 'vendor/golang.org/x/crypto/openpgp')
29 files changed, 7242 insertions, 0 deletions
diff --git a/vendor/golang.org/x/crypto/openpgp/LICENSE b/vendor/golang.org/x/crypto/openpgp/LICENSE new file mode 100644 index 00000000..6a66aea5 --- /dev/null +++ b/vendor/golang.org/x/crypto/openpgp/LICENSE @@ -0,0 +1,27 @@ +Copyright (c) 2009 The Go Authors. All rights reserved. + +Redistribution and use in source and binary forms, with or without +modification, are permitted provided that the following conditions are +met: + + * Redistributions of source code must retain the above copyright +notice, this list of conditions and the following disclaimer. + * Redistributions in binary form must reproduce the above +copyright notice, this list of conditions and the following disclaimer +in the documentation and/or other materials provided with the +distribution. + * Neither the name of Google Inc. nor the names of its +contributors may be used to endorse or promote products derived from +this software without specific prior written permission. + +THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. diff --git a/vendor/golang.org/x/crypto/openpgp/armor/armor.go b/vendor/golang.org/x/crypto/openpgp/armor/armor.go new file mode 100644 index 00000000..592d1864 --- /dev/null +++ b/vendor/golang.org/x/crypto/openpgp/armor/armor.go @@ -0,0 +1,219 @@ +// 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 "golang.org/x/crypto/openpgp/armor" + +import ( + "bufio" + "bytes" + "encoding/base64" + "golang.org/x/crypto/openpgp/errors" + "io" +) + +// 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 error = errors.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 error) { + if l.eof { + return 0, io.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 != io.EOF { + return + } + if !bytes.HasPrefix(line, armorEnd) { + return 0, ArmorCorrupt + } + + l.eof = true + return 0, io.EOF + } + + if len(line) > 96 { + 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 error) { + n, err = r.b64Reader.Read(p) + r.currentCRC = crc24(r.currentCRC, p[:n]) + + if err == io.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, io.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 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/vendor/golang.org/x/crypto/openpgp/armor/encode.go b/vendor/golang.org/x/crypto/openpgp/armor/encode.go new file mode 100644 index 00000000..6f07582c --- /dev/null +++ b/vendor/golang.org/x/crypto/openpgp/armor/encode.go @@ -0,0 +1,160 @@ +// 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" +) + +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 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 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 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 error) { + e.crc = crc24(e.crc, data) + return e.b64.Write(data) +} + +func (e *encoding) Close() (err 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 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/vendor/golang.org/x/crypto/openpgp/canonical_text.go b/vendor/golang.org/x/crypto/openpgp/canonical_text.go new file mode 100644 index 00000000..e601e389 --- /dev/null +++ b/vendor/golang.org/x/crypto/openpgp/canonical_text.go @@ -0,0 +1,59 @@ +// 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" + +// 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, 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(in []byte) []byte { + return cth.h.Sum(in) +} + +func (cth *canonicalTextHash) Reset() { + cth.h.Reset() + cth.s = 0 +} + +func (cth *canonicalTextHash) Size() int { + return cth.h.Size() +} + +func (cth *canonicalTextHash) BlockSize() int { + return cth.h.BlockSize() +} diff --git a/vendor/golang.org/x/crypto/openpgp/clearsign/clearsign.go b/vendor/golang.org/x/crypto/openpgp/clearsign/clearsign.go new file mode 100644 index 00000000..def4caba --- /dev/null +++ b/vendor/golang.org/x/crypto/openpgp/clearsign/clearsign.go @@ -0,0 +1,376 @@ +// Copyright 2012 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 clearsign generates and processes OpenPGP, clear-signed data. See +// RFC 4880, section 7. +// +// Clearsigned messages are cryptographically signed, but the contents of the +// message are kept in plaintext so that it can be read without special tools. +package clearsign // import "golang.org/x/crypto/openpgp/clearsign" + +import ( + "bufio" + "bytes" + "crypto" + "hash" + "io" + "net/textproto" + "strconv" + + "golang.org/x/crypto/openpgp/armor" + "golang.org/x/crypto/openpgp/errors" + "golang.org/x/crypto/openpgp/packet" +) + +// A Block represents a clearsigned message. A signature on a Block can +// be checked by passing Bytes into openpgp.CheckDetachedSignature. +type Block struct { + Headers textproto.MIMEHeader // Optional message headers + Plaintext []byte // The original message text + Bytes []byte // The signed message + ArmoredSignature *armor.Block // The signature block +} + +// start is the marker which denotes the beginning of a clearsigned message. +var start = []byte("\n-----BEGIN PGP SIGNED MESSAGE-----") + +// dashEscape is prefixed to any lines that begin with a hyphen so that they +// can't be confused with endText. +var dashEscape = []byte("- ") + +// endText is a marker which denotes the end of the message and the start of +// an armored signature. +var endText = []byte("-----BEGIN PGP SIGNATURE-----") + +// end is a marker which denotes the end of the armored signature. +var end = []byte("\n-----END PGP SIGNATURE-----") + +var crlf = []byte("\r\n") +var lf = byte('\n') + +// getLine returns the first \r\n or \n delineated line from the given byte +// array. The line does not include the \r\n or \n. The remainder of the byte +// array (also not including the new line bytes) is also returned and this will +// always be smaller than the original argument. +func getLine(data []byte) (line, rest []byte) { + i := bytes.Index(data, []byte{'\n'}) + var j int + if i < 0 { + i = len(data) + j = i + } else { + j = i + 1 + if i > 0 && data[i-1] == '\r' { + i-- + } + } + return data[0:i], data[j:] +} + +// Decode finds the first clearsigned message in data and returns it, as well +// as the suffix of data which remains after the message. +func Decode(data []byte) (b *Block, rest []byte) { + // start begins with a newline. However, at the very beginning of + // the byte array, we'll accept the start string without it. + rest = data + if bytes.HasPrefix(data, start[1:]) { + rest = rest[len(start)-1:] + } else if i := bytes.Index(data, start); i >= 0 { + rest = rest[i+len(start):] + } else { + return nil, data + } + + // Consume the start line. + _, rest = getLine(rest) + + var line []byte + b = &Block{ + Headers: make(textproto.MIMEHeader), + } + + // Next come a series of header lines. + for { + // This loop terminates because getLine's second result is + // always smaller than its argument. + if len(rest) == 0 { + return nil, data + } + // An empty line marks the end of the headers. + if line, rest = getLine(rest); len(line) == 0 { + break + } + + i := bytes.Index(line, []byte{':'}) + if i == -1 { + return nil, data + } + + key, val := line[0:i], line[i+1:] + key = bytes.TrimSpace(key) + val = bytes.TrimSpace(val) + b.Headers.Add(string(key), string(val)) + } + + firstLine := true + for { + start := rest + + line, rest = getLine(rest) + if len(line) == 0 && len(rest) == 0 { + // No armored data was found, so this isn't a complete message. + return nil, data + } + if bytes.Equal(line, endText) { + // Back up to the start of the line because armor expects to see the + // header line. + rest = start + break + } + + // The final CRLF isn't included in the hash so we don't write it until + // we've seen the next line. + if firstLine { + firstLine = false + } else { + b.Bytes = append(b.Bytes, crlf...) + } + + if bytes.HasPrefix(line, dashEscape) { + line = line[2:] + } + line = bytes.TrimRight(line, " \t") + b.Bytes = append(b.Bytes, line...) + + b.Plaintext = append(b.Plaintext, line...) + b.Plaintext = append(b.Plaintext, lf) + } + + // We want to find the extent of the armored data (including any newlines at + // the end). + i := bytes.Index(rest, end) + if i == -1 { + return nil, data + } + i += len(end) + for i < len(rest) && (rest[i] == '\r' || rest[i] == '\n') { + i++ + } + armored := rest[:i] + rest = rest[i:] + + var err error + b.ArmoredSignature, err = armor.Decode(bytes.NewBuffer(armored)) + if err != nil { + return nil, data + } + + return b, rest +} + +// A dashEscaper is an io.WriteCloser which processes the body of a clear-signed +// message. The clear-signed message is written to buffered and a hash, suitable +// for signing, is maintained in h. +// +// When closed, an armored signature is created and written to complete the +// message. +type dashEscaper struct { + buffered *bufio.Writer + h hash.Hash + hashType crypto.Hash + + atBeginningOfLine bool + isFirstLine bool + + whitespace []byte + byteBuf []byte // a one byte buffer to save allocations + + privateKey *packet.PrivateKey + config *packet.Config +} + +func (d *dashEscaper) Write(data []byte) (n int, err error) { + for _, b := range data { + d.byteBuf[0] = b + + if d.atBeginningOfLine { + // The final CRLF isn't included in the hash so we have to wait + // until this point (the start of the next line) before writing it. + if !d.isFirstLine { + d.h.Write(crlf) + } + d.isFirstLine = false + } + + // Any whitespace at the end of the line has to be removed so we + // buffer it until we find out whether there's more on this line. + if b == ' ' || b == '\t' || b == '\r' { + d.whitespace = append(d.whitespace, b) + d.atBeginningOfLine = false + continue + } + + if d.atBeginningOfLine { + // At the beginning of a line, hyphens have to be escaped. + if b == '-' { + // The signature isn't calculated over the dash-escaped text so + // the escape is only written to buffered. + if _, err = d.buffered.Write(dashEscape); err != nil { + return + } + d.h.Write(d.byteBuf) + d.atBeginningOfLine = false + } else if b == '\n' { + // Nothing to do because we delay writing CRLF to the hash. + } else { + d.h.Write(d.byteBuf) + d.atBeginningOfLine = false + } + if err = d.buffered.WriteByte(b); err != nil { + return + } + } else { + if b == '\n' { + // We got a raw \n. Drop any trailing whitespace and write a + // CRLF. + d.whitespace = d.whitespace[:0] + // We delay writing CRLF to the hash until the start of the + // next line. + if err = d.buffered.WriteByte(b); err != nil { + return + } + d.atBeginningOfLine = true + } else { + // Any buffered whitespace wasn't at the end of the line so + // we need to write it out. + if len(d.whitespace) > 0 { + d.h.Write(d.whitespace) + if _, err = d.buffered.Write(d.whitespace); err != nil { + return + } + d.whitespace = d.whitespace[:0] + } + d.h.Write(d.byteBuf) + if err = d.buffered.WriteByte(b); err != nil { + return + } + } + } + } + + n = len(data) + return +} + +func (d *dashEscaper) Close() (err error) { + if !d.atBeginningOfLine { + if err = d.buffered.WriteByte(lf); err != nil { + return + } + } + sig := new(packet.Signature) + sig.SigType = packet.SigTypeText + sig.PubKeyAlgo = d.privateKey.PubKeyAlgo + sig.Hash = d.hashType + sig.CreationTime = d.config.Now() + sig.IssuerKeyId = &d.privateKey.KeyId + + if err = sig.Sign(d.h, d.privateKey, d.config); err != nil { + return + } + + out, err := armor.Encode(d.buffered, "PGP SIGNATURE", nil) + if err != nil { + return + } + + if err = sig.Serialize(out); err != nil { + return + } + if err = out.Close(); err != nil { + return + } + if err = d.buffered.Flush(); err != nil { + return + } + return +} + +// Encode returns a WriteCloser which will clear-sign a message with privateKey +// and write it to w. If config is nil, sensible defaults are used. +func Encode(w io.Writer, privateKey *packet.PrivateKey, config *packet.Config) (plaintext io.WriteCloser, err error) { + if privateKey.Encrypted { + return nil, errors.InvalidArgumentError("signing key is encrypted") + } + + hashType := config.Hash() + name := nameOfHash(hashType) + if len(name) == 0 { + return nil, errors.UnsupportedError("unknown hash type: " + strconv.Itoa(int(hashType))) + } + + if !hashType.Available() { + return nil, errors.UnsupportedError("unsupported hash type: " + strconv.Itoa(int(hashType))) + } + h := hashType.New() + + buffered := bufio.NewWriter(w) + // start has a \n at the beginning that we don't want here. + if _, err = buffered.Write(start[1:]); err != nil { + return + } + if err = buffered.WriteByte(lf); err != nil { + return + } + if _, err = buffered.WriteString("Hash: "); err != nil { + return + } + if _, err = buffered.WriteString(name); err != nil { + return + } + if err = buffered.WriteByte(lf); err != nil { + return + } + if err = buffered.WriteByte(lf); err != nil { + return + } + + plaintext = &dashEscaper{ + buffered: buffered, + h: h, + hashType: hashType, + + atBeginningOfLine: true, + isFirstLine: true, + + byteBuf: make([]byte, 1), + + privateKey: privateKey, + config: config, + } + + return +} + +// nameOfHash returns the OpenPGP name for the given hash, or the empty string +// if the name isn't known. See RFC 4880, section 9.4. +func nameOfHash(h crypto.Hash) string { + switch h { + case crypto.MD5: + return "MD5" + case crypto.SHA1: + return "SHA1" + case crypto.RIPEMD160: + return "RIPEMD160" + case crypto.SHA224: + return "SHA224" + case crypto.SHA256: + return "SHA256" + case crypto.SHA384: + return "SHA384" + case crypto.SHA512: + return "SHA512" + } + return "" +} diff --git a/vendor/golang.org/x/crypto/openpgp/elgamal/elgamal.go b/vendor/golang.org/x/crypto/openpgp/elgamal/elgamal.go new file mode 100644 index 00000000..73f4fe37 --- /dev/null +++ b/vendor/golang.org/x/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 "golang.org/x/crypto/openpgp/elgamal" + +import ( + "crypto/rand" + "crypto/subtle" + "errors" + "io" + "math/big" +) + +// 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 error) { + pLen := (pub.P.BitLen() + 7) / 8 + if len(msg) > pLen-11 { + err = errors.New("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 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, errors.New("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 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/vendor/golang.org/x/crypto/openpgp/errors/errors.go b/vendor/golang.org/x/crypto/openpgp/errors/errors.go new file mode 100644 index 00000000..eb0550b2 --- /dev/null +++ b/vendor/golang.org/x/crypto/openpgp/errors/errors.go @@ -0,0 +1,72 @@ +// 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 errors contains common error types for the OpenPGP packages. +package errors // import "golang.org/x/crypto/openpgp/errors" + +import ( + "strconv" +) + +// A StructuralError is returned when OpenPGP data is found to be syntactically +// invalid. +type StructuralError string + +func (s StructuralError) Error() string { + return "openpgp: invalid data: " + string(s) +} + +// UnsupportedError indicates that, although the OpenPGP data is valid, it +// makes use of currently unimplemented features. +type UnsupportedError string + +func (s UnsupportedError) Error() string { + return "openpgp: unsupported feature: " + string(s) +} + +// InvalidArgumentError indicates that the caller is in error and passed an +// incorrect value. +type InvalidArgumentError string + +func (i InvalidArgumentError) Error() string { + return "openpgp: invalid argument: " + string(i) +} + +// SignatureError indicates that a syntactically valid signature failed to +// validate. +type SignatureError string + +func (b SignatureError) Error() string { + return "openpgp: invalid signature: " + string(b) +} + +type keyIncorrectError int + +func (ki keyIncorrectError) Error() string { + return "openpgp: incorrect key" +} + +var ErrKeyIncorrect error = keyIncorrectError(0) + +type unknownIssuerError int + +func (unknownIssuerError) Error() string { + return "openpgp: signature made by unknown entity" +} + +var ErrUnknownIssuer error = unknownIssuerError(0) + +type keyRevokedError int + +func (keyRevokedError) Error() string { + return "openpgp: signature made by revoked key" +} + +var ErrKeyRevoked error = keyRevokedError(0) + +type UnknownPacketTypeError uint8 + +func (upte UnknownPacketTypeError) Error() string { + return "openpgp: unknown packet type: " + strconv.Itoa(int(upte)) +} diff --git a/vendor/golang.org/x/crypto/openpgp/keys.go b/vendor/golang.org/x/crypto/openpgp/keys.go new file mode 100644 index 00000000..fd582a89 --- /dev/null +++ b/vendor/golang.org/x/crypto/openpgp/keys.go @@ -0,0 +1,641 @@ +// 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/rsa" + "io" + "time" + + "golang.org/x/crypto/openpgp/armor" + "golang.org/x/crypto/openpgp/errors" + "golang.org/x/crypto/openpgp/packet" +) + +// 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 + Revocations []*packet.Signature + 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 + // KeysByIdAndUsage returns the set of keys with the given id + // that also meet the key usage given by requiredUsage. + // The requiredUsage is expressed as the bitwise-OR of + // packet.KeyFlag* values. + KeysByIdUsage(id uint64, requiredUsage byte) []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(now time.Time) (Key, bool) { + candidateSubkey := -1 + + // Iterate the keys to find the newest key + var maxTime time.Time + for i, subkey := range e.Subkeys { + if subkey.Sig.FlagsValid && + subkey.Sig.FlagEncryptCommunications && + subkey.PublicKey.PubKeyAlgo.CanEncrypt() && + !subkey.Sig.KeyExpired(now) && + (maxTime.IsZero() || subkey.Sig.CreationTime.After(maxTime)) { + candidateSubkey = i + maxTime = subkey.Sig.CreationTime + } + } + + if candidateSubkey != -1 { + subkey := e.Subkeys[candidateSubkey] + return Key{e, subkey.PublicKey, subkey.PrivateKey, subkey.Sig}, true + } + + // 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. + i := e.primaryIdentity() + if !i.SelfSignature.FlagsValid || i.SelfSignature.FlagEncryptCommunications && + e.PrimaryKey.PubKeyAlgo.CanEncrypt() && + !i.SelfSignature.KeyExpired(now) { + return Key{e, e.PrimaryKey, e.PrivateKey, i.SelfSignature}, true + } + + // This Entity appears to be signing only. + return Key{}, false +} + +// signingKey return the best candidate Key for signing a message with this +// Entity. +func (e *Entity) signingKey(now time.Time) (Key, bool) { + candidateSubkey := -1 + + for i, subkey := range e.Subkeys { + if subkey.Sig.FlagsValid && + subkey.Sig.FlagSign && + subkey.PublicKey.PubKeyAlgo.CanSign() && + !subkey.Sig.KeyExpired(now) { + candidateSubkey = i + break + } + } + + if candidateSubkey != -1 { + subkey := e.Subkeys[candidateSubkey] + return Key{e, subkey.PublicKey, subkey.PrivateKey, subkey.Sig}, true + } + + // If we have no candidate subkey then we assume that it's ok to sign + // with the primary key. + i := e.primaryIdentity() + if !i.SelfSignature.FlagsValid || i.SelfSignature.FlagSign && + !i.SelfSignature.KeyExpired(now) { + return Key{e, e.PrimaryKey, e.PrivateKey, i.SelfSignature}, true + } + + return Key{}, false +} + +// 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 +} + +// KeysByIdAndUsage returns the set of keys with the given id that also meet +// the key usage given by requiredUsage. The requiredUsage is expressed as +// the bitwise-OR of packet.KeyFlag* values. +func (el EntityList) KeysByIdUsage(id uint64, requiredUsage byte) (keys []Key) { + for _, key := range el.KeysById(id) { + if len(key.Entity.Revocations) > 0 { + continue + } + + if key.SelfSignature.RevocationReason != nil { + continue + } + + if key.SelfSignature.FlagsValid && requiredUsage != 0 { + var usage byte + if key.SelfSignature.FlagCertify { + usage |= packet.KeyFlagCertify + } + if key.SelfSignature.FlagSign { + usage |= packet.KeyFlagSign + } + if key.SelfSignature.FlagEncryptCommunications { + usage |= packet.KeyFlagEncryptCommunications + } + if key.SelfSignature.FlagEncryptStorage { + usage |= packet.KeyFlagEncryptStorage + } + if usage&requiredUsage != requiredUsage { + continue + } + } + + keys = append(keys, key) + } + 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, error) { + block, err := armor.Decode(r) + if err == io.EOF { + return nil, errors.InvalidArgumentError("no armored data found") + } + if err != nil { + return nil, err + } + if block.Type != PublicKeyType && block.Type != PrivateKeyType { + return nil, errors.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 error) { + packets := packet.NewReader(r) + var lastUnsupportedError error + + for { + var e *Entity + e, err = ReadEntity(packets) + if err != nil { + // TODO: warn about skipped unsupported/unreadable keys + if _, ok := err.(errors.UnsupportedError); ok { + lastUnsupportedError = err + err = readToNextPublicKey(packets) + } else if _, ok := err.(errors.StructuralError); ok { + // Skip unreadable, badly-formatted keys + lastUnsupportedError = err + err = readToNextPublicKey(packets) + } + if err == io.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 error) { + var p packet.Packet + for { + p, err = packets.Next() + if err == io.EOF { + return + } else if err != nil { + if _, ok := err.(errors.UnsupportedError); ok { + err = nil + continue + } + return + } + + if pk, ok := p.(*packet.PublicKey); ok && !pk.IsSubkey { + packets.Unread(p) + return + } + } +} + +// ReadEntity reads an entity (public key, identities, subkeys etc) from the +// given Reader. +func ReadEntity(packets *packet.Reader) (*Entity, 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, errors.StructuralError("first packet was not a public/private key") + } + e.PrimaryKey = &e.PrivateKey.PublicKey + } + + if !e.PrimaryKey.PubKeyAlgo.CanSign() { + return nil, errors.StructuralError("primary key cannot be used for signatures") + } + + var current *Identity + var revocations []*packet.Signature +EachPacket: + for { + p, err := packets.Next() + if err == io.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 == io.EOF { + return nil, io.ErrUnexpectedEOF + } else if err != nil { + return nil, err + } + + sig, ok := p.(*packet.Signature) + if !ok { + return nil, errors.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, e.PrimaryKey, sig); err != nil { + return nil, errors.StructuralError("user ID self-signature invalid: " + err.Error()) + } + current.SelfSignature = sig + break + } + current.Signatures = append(current.Signatures, sig) + } + case *packet.Signature: + if pkt.SigType == packet.SigTypeKeyRevocation { + revocations = append(revocations, pkt) + } else if pkt.SigType == packet.SigTypeDirectSignature { + // TODO: RFC4880 5.2.1 permits signatures + // directly on keys (eg. to bind additional + // revocation keys). + } else if current == nil { + return nil, errors.StructuralError("signature packet found before user id packet") + } else { + 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, errors.StructuralError("entity without any identities") + } + + for _, revocation := range revocations { + err = e.PrimaryKey.VerifyRevocationSignature(revocation) + if err == nil { + e.Revocations = append(e.Revocations, revocation) + } else { + // TODO: RFC 4880 5.2.3.15 defines revocation keys. + return nil, errors.StructuralError("revocation signature signed by alternate key") + } + } + + return e, nil +} + +func addSubkey(e *Entity, packets *packet.Reader, pub *packet.PublicKey, priv *packet.PrivateKey) error { + var subKey Subkey + subKey.PublicKey = pub + subKey.PrivateKey = priv + p, err := packets.Next() + if err == io.EOF { + return io.ErrUnexpectedEOF + } + if err != nil { + return errors.StructuralError("subkey signature invalid: " + err.Error()) + } + var ok bool + subKey.Sig, ok = p.(*packet.Signature) + if !ok { + return errors.StructuralError("subkey packet not followed by signature") + } + if subKey.Sig.SigType != packet.SigTypeSubkeyBinding && subKey.Sig.SigType != packet.SigTypeSubkeyRevocation { + return errors.StructuralError("subkey signature with wrong type") + } + err = e.PrimaryKey.VerifyKeySignature(subKey.PublicKey, subKey.Sig) + if err != nil { + return errors.StructuralError("subkey signature invalid: " + err.Error()) + } + 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". +// If config is nil, sensible defaults will be used. +func NewEntity(name, comment, email string, config *packet.Config) (*Entity, error) { + currentTime := config.Now() + + bits := defaultRSAKeyBits + if config != nil && config.RSABits != 0 { + bits = config.RSABits + } + + uid := packet.NewUserId(name, comment, email) + if uid == nil { + return nil, errors.InvalidArgumentError("user id field contained invalid characters") + } + signingPriv, err := rsa.GenerateKey(config.Random(), bits) + if err != nil { + return nil, err + } + encryptingPriv, err := rsa.GenerateKey(config.Random(), bits) + if err != nil { + return nil, err + } + + e := &Entity{ + PrimaryKey: packet.NewRSAPublicKey(currentTime, &signingPriv.PublicKey), + PrivateKey: packet.NewRSAPrivateKey(currentTime, signingPriv), + Identities: make(map[string]*Identity), + } + isPrimaryId := true + e.Identities[uid.Id] = &Identity{ + Name: uid.Id, + UserId: uid, + SelfSignature: &packet.Signature{ + CreationTime: currentTime, + SigType: packet.SigTypePositiveCert, + PubKeyAlgo: packet.PubKeyAlgoRSA, + Hash: config.Hash(), + IsPrimaryId: &isPrimaryId, + FlagsValid: true, + FlagSign: true, + FlagCertify: true, + IssuerKeyId: &e.PrimaryKey.KeyId, + }, + } + + // If the user passes in a DefaultHash via packet.Config, + // set the PreferredHash for the SelfSignature. + if config != nil && config.DefaultHash != 0 { + e.Identities[uid.Id].SelfSignature.PreferredHash = []uint8{hashToHashId(config.DefaultHash)} + } + + // Likewise for DefaultCipher. + if config != nil && config.DefaultCipher != 0 { + e.Identities[uid.Id].SelfSignature.PreferredSymmetric = []uint8{uint8(config.DefaultCipher)} + } + + e.Subkeys = make([]Subkey, 1) + e.Subkeys[0] = Subkey{ + PublicKey: packet.NewRSAPublicKey(currentTime, &encryptingPriv.PublicKey), + PrivateKey: packet.NewRSAPrivateKey(currentTime, encryptingPriv), + Sig: &packet.Signature{ + CreationTime: currentTime, + SigType: packet.SigTypeSubkeyBinding, + PubKeyAlgo: packet.PubKeyAlgoRSA, + Hash: config.Hash(), + FlagsValid: true, + FlagEncryptStorage: true, + FlagEncryptCommunications: true, + IssuerKeyId: &e.PrimaryKey.KeyId, + }, + } + e.Subkeys[0].PublicKey.IsSubkey = true + e.Subkeys[0].PrivateKey.IsSubkey = true + + 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. +// If config is nil, sensible defaults will be used. +func (e *Entity) SerializePrivate(w io.Writer, config *packet.Config) (err 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, config) + 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, config) + 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) 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. +// If config is nil, sensible defaults will be used. +func (e *Entity) SignIdentity(identity string, signer *Entity, config *packet.Config) error { + if signer.PrivateKey == nil { + return errors.InvalidArgumentError("signing Entity must have a private key") + } + if signer.PrivateKey.Encrypted { + return errors.InvalidArgumentError("signing Entity's private key must be decrypted") + } + ident, ok := e.Identities[identity] + if !ok { + return errors.InvalidArgumentError("given identity string not found in Entity") + } + + sig := &packet.Signature{ + SigType: packet.SigTypeGenericCert, + PubKeyAlgo: signer.PrivateKey.PubKeyAlgo, + Hash: config.Hash(), + CreationTime: config.Now(), + IssuerKeyId: &signer.PrivateKey.KeyId, + } + if err := sig.SignUserId(identity, e.PrimaryKey, signer.PrivateKey, config); err != nil { + return err + } + ident.Signatures = append(ident.Signatures, sig) + return nil +} diff --git a/vendor/golang.org/x/crypto/openpgp/packet/compressed.go b/vendor/golang.org/x/crypto/openpgp/packet/compressed.go new file mode 100644 index 00000000..e8f0b5ca --- /dev/null +++ b/vendor/golang.org/x/crypto/openpgp/packet/compressed.go @@ -0,0 +1,123 @@ +// 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/bzip2" + "compress/flate" + "compress/zlib" + "golang.org/x/crypto/openpgp/errors" + "io" + "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 +} + +const ( + NoCompression = flate.NoCompression + BestSpeed = flate.BestSpeed + BestCompression = flate.BestCompression + DefaultCompression = flate.DefaultCompression +) + +// CompressionConfig contains compressor configuration settings. +type CompressionConfig struct { + // Level is the compression level to use. It must be set to + // between -1 and 9, with -1 causing the compressor to use the + // default compression level, 0 causing the compressor to use + // no compression and 1 to 9 representing increasing (better, + // slower) compression levels. If Level is less than -1 or + // more then 9, a non-nil error will be returned during + // encryption. See the constants above for convenient common + // settings for Level. + Level int +} + +func (c *Compressed) parse(r io.Reader) 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) + case 3: + c.Body = bzip2.NewReader(r) + default: + err = errors.UnsupportedError("unknown compression algorithm: " + strconv.Itoa(int(buf[0]))) + } + + return err +} + +// compressedWriterCloser represents the serialized compression stream +// header and the compressor. Its Close() method ensures that both the +// compressor and serialized stream header are closed. Its Write() +// method writes to the compressor. +type compressedWriteCloser struct { + sh io.Closer // Stream Header + c io.WriteCloser // Compressor +} + +func (cwc compressedWriteCloser) Write(p []byte) (int, error) { + return cwc.c.Write(p) +} + +func (cwc compressedWriteCloser) Close() (err error) { + err = cwc.c.Close() + if err != nil { + return err + } + + return cwc.sh.Close() +} + +// SerializeCompressed serializes a compressed data packet to w and +// returns a WriteCloser to which the literal data packets themselves +// can be written and which MUST be closed on completion. If cc is +// nil, sensible defaults will be used to configure the compression +// algorithm. +func SerializeCompressed(w io.WriteCloser, algo CompressionAlgo, cc *CompressionConfig) (literaldata io.WriteCloser, err error) { + compressed, err := serializeStreamHeader(w, packetTypeCompressed) + if err != nil { + return + } + + _, err = compressed.Write([]byte{uint8(algo)}) + if err != nil { + return + } + + level := DefaultCompression + if cc != nil { + level = cc.Level + } + + var compressor io.WriteCloser + switch algo { + case CompressionZIP: + compressor, err = flate.NewWriter(compressed, level) + case CompressionZLIB: + compressor, err = zlib.NewWriterLevel(compressed, level) + default: + s := strconv.Itoa(int(algo)) + err = errors.UnsupportedError("Unsupported compression algorithm: " + s) + } + if err != nil { + return + } + + literaldata = compressedWriteCloser{compressed, compressor} + + return +} diff --git a/vendor/golang.org/x/crypto/openpgp/packet/config.go b/vendor/golang.org/x/crypto/openpgp/packet/config.go new file mode 100644 index 00000000..c76eecc9 --- /dev/null +++ b/vendor/golang.org/x/crypto/openpgp/packet/config.go @@ -0,0 +1,91 @@ +// Copyright 2012 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/rand" + "io" + "time" +) + +// Config collects a number of parameters along with sensible defaults. +// A nil *Config is valid and results in all default values. +type Config struct { + // Rand provides the source of entropy. + // If nil, the crypto/rand Reader is used. + Rand io.Reader + // DefaultHash is the default hash function to be used. + // If zero, SHA-256 is used. + DefaultHash crypto.Hash + // DefaultCipher is the cipher to be used. + // If zero, AES-128 is used. + DefaultCipher CipherFunction + // Time returns the current time as the number of seconds since the + // epoch. If Time is nil, time.Now is used. + Time func() time.Time + // DefaultCompressionAlgo is the compression algorithm to be + // applied to the plaintext before encryption. If zero, no + // compression is done. + DefaultCompressionAlgo CompressionAlgo + // CompressionConfig configures the compression settings. + CompressionConfig *CompressionConfig + // S2KCount is only used for symmetric encryption. It + // determines the strength of the passphrase stretching when + // the said passphrase is hashed to produce a key. S2KCount + // should be between 1024 and 65011712, inclusive. If Config + // is nil or S2KCount is 0, the value 65536 used. Not all + // values in the above range can be represented. S2KCount will + // be rounded up to the next representable value if it cannot + // be encoded exactly. When set, it is strongly encrouraged to + // use a value that is at least 65536. See RFC 4880 Section + // 3.7.1.3. + S2KCount int + // RSABits is the number of bits in new RSA keys made with NewEntity. + // If zero, then 2048 bit keys are created. + RSABits int +} + +func (c *Config) Random() io.Reader { + if c == nil || c.Rand == nil { + return rand.Reader + } + return c.Rand +} + +func (c *Config) Hash() crypto.Hash { + if c == nil || uint(c.DefaultHash) == 0 { + return crypto.SHA256 + } + return c.DefaultHash +} + +func (c *Config) Cipher() CipherFunction { + if c == nil || uint8(c.DefaultCipher) == 0 { + return CipherAES128 + } + return c.DefaultCipher +} + +func (c *Config) Now() time.Time { + if c == nil || c.Time == nil { + return time.Now() + } + return c.Time() +} + +func (c *Config) Compression() CompressionAlgo { + if c == nil { + return CompressionNone + } + return c.DefaultCompressionAlgo +} + +func (c *Config) PasswordHashIterations() int { + if c == nil || c.S2KCount == 0 { + return 0 + } + return c.S2KCount +} diff --git a/vendor/golang.org/x/crypto/openpgp/packet/encrypted_key.go b/vendor/golang.org/x/crypto/openpgp/packet/encrypted_key.go new file mode 100644 index 00000000..266840d0 --- /dev/null +++ b/vendor/golang.org/x/crypto/openpgp/packet/encrypted_key.go @@ -0,0 +1,199 @@ +// 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/rsa" + "encoding/binary" + "io" + "math/big" + "strconv" + + "golang.org/x/crypto/openpgp/elgamal" + "golang.org/x/crypto/openpgp/errors" +) + +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 parsedMPI +} + +func (e *EncryptedKey) parse(r io.Reader) (err error) { + var buf [10]byte + _, err = readFull(r, buf[:]) + if err != nil { + return + } + if buf[0] != encryptedKeyVersion { + return errors.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.bytes, e.encryptedMPI1.bitLength, err = readMPI(r) + case PubKeyAlgoElGamal: + e.encryptedMPI1.bytes, e.encryptedMPI1.bitLength, err = readMPI(r) + if err != nil { + return + } + e.encryptedMPI2.bytes, e.encryptedMPI2.bitLength, 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. +// If config is nil, sensible defaults will be used. +func (e *EncryptedKey) Decrypt(priv *PrivateKey, config *Config) error { + var err 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(config.Random(), priv.PrivateKey.(*rsa.PrivateKey), e.encryptedMPI1.bytes) + case PubKeyAlgoElGamal: + c1 := new(big.Int).SetBytes(e.encryptedMPI1.bytes) + c2 := new(big.Int).SetBytes(e.encryptedMPI2.bytes) + b, err = elgamal.Decrypt(priv.PrivateKey.(*elgamal.PrivateKey), c1, c2) + default: + err = errors.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 errors.StructuralError("EncryptedKey checksum incorrect") + } + + return nil +} + +// Serialize writes the encrypted key packet, e, to w. +func (e *EncryptedKey) Serialize(w io.Writer) error { + var mpiLen int + switch e.Algo { + case PubKeyAlgoRSA, PubKeyAlgoRSAEncryptOnly: + mpiLen = 2 + len(e.encryptedMPI1.bytes) + case PubKeyAlgoElGamal: + mpiLen = 2 + len(e.encryptedMPI1.bytes) + 2 + len(e.encryptedMPI2.bytes) + default: + return errors.InvalidArgumentError("don't know how to serialize encrypted key type " + strconv.Itoa(int(e.Algo))) + } + + serializeHeader(w, packetTypeEncryptedKey, 1 /* version */ +8 /* key id */ +1 /* algo */ +mpiLen) + + w.Write([]byte{encryptedKeyVersion}) + binary.Write(w, binary.BigEndian, e.KeyId) + w.Write([]byte{byte(e.Algo)}) + + switch e.Algo { + case PubKeyAlgoRSA, PubKeyAlgoRSAEncryptOnly: + writeMPIs(w, e.encryptedMPI1) + case PubKeyAlgoElGamal: + writeMPIs(w, e.encryptedMPI1, e.encryptedMPI2) + default: + panic("internal error") + } + + return nil +} + +// SerializeEncryptedKey serializes an encrypted key packet to w that contains +// key, encrypted to pub. +// If config is nil, sensible defaults will be used. +func SerializeEncryptedKey(w io.Writer, pub *PublicKey, cipherFunc CipherFunction, key []byte, config *Config) 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, config.Random(), buf, pub.PublicKey.(*rsa.PublicKey), keyBlock) + case PubKeyAlgoElGamal: + return serializeEncryptedKeyElGamal(w, config.Random(), buf, pub.PublicKey.(*elgamal.PublicKey), keyBlock) + case PubKeyAlgoDSA, PubKeyAlgoRSASignOnly: + return errors.InvalidArgumentError("cannot encrypt to public key of type " + strconv.Itoa(int(pub.PubKeyAlgo))) + } + + return errors.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) error { + cipherText, err := rsa.EncryptPKCS1v15(rand, pub, keyBlock) + if err != nil { + return errors.InvalidArgumentError("RSA encryption failed: " + err.Error()) + } + + 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) error { + c1, c2, err := elgamal.Encrypt(rand, pub, keyBlock) + if err != nil { + return errors.InvalidArgumentError("ElGamal encryption failed: " + err.Error()) + } + + 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/vendor/golang.org/x/crypto/openpgp/packet/literal.go b/vendor/golang.org/x/crypto/openpgp/packet/literal.go new file mode 100644 index 00000000..1a9ec6e5 --- /dev/null +++ b/vendor/golang.org/x/crypto/openpgp/packet/literal.go @@ -0,0 +1,89 @@ +// 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" +) + +// 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 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 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/vendor/golang.org/x/crypto/openpgp/packet/ocfb.go b/vendor/golang.org/x/crypto/openpgp/packet/ocfb.go new file mode 100644 index 00000000..ce2a33a5 --- /dev/null +++ b/vendor/golang.org/x/crypto/openpgp/packet/ocfb.go @@ -0,0 +1,143 @@ +// 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. + +// OpenPGP CFB Mode. http://tools.ietf.org/html/rfc4880#section-13.9 + +package packet + +import ( + "crypto/cipher" +) + +type ocfbEncrypter struct { + b cipher.Block + fre []byte + outUsed int +} + +// An OCFBResyncOption determines if the "resynchronization step" of OCFB is +// performed. +type OCFBResyncOption bool + +const ( + OCFBResync OCFBResyncOption = true + OCFBNoResync OCFBResyncOption = false +) + +// NewOCFBEncrypter returns a cipher.Stream which encrypts data with OpenPGP's +// cipher feedback mode using the given cipher.Block, and an initial amount of +// ciphertext. randData must be random bytes and be the same length as the +// cipher.Block's block size. Resync determines if the "resynchronization step" +// from RFC 4880, 13.9 step 7 is performed. Different parts of OpenPGP vary on +// this point. +func NewOCFBEncrypter(block cipher.Block, randData []byte, resync OCFBResyncOption) (cipher.Stream, []byte) { + blockSize := block.BlockSize() + if len(randData) != blockSize { + return nil, nil + } + + x := &ocfbEncrypter{ + b: block, + fre: make([]byte, blockSize), + outUsed: 0, + } + prefix := make([]byte, blockSize+2) + + block.Encrypt(x.fre, x.fre) + for i := 0; i < blockSize; i++ { + prefix[i] = randData[i] ^ x.fre[i] + } + + block.Encrypt(x.fre, prefix[:blockSize]) + prefix[blockSize] = x.fre[0] ^ randData[blockSize-2] + prefix[blockSize+1] = x.fre[1] ^ randData[blockSize-1] + + if resync { + block.Encrypt(x.fre, prefix[2:]) + } else { + x.fre[0] = prefix[blockSize] + x.fre[1] = prefix[blockSize+1] + x.outUsed = 2 + } + return x, prefix +} + +func (x *ocfbEncrypter) XORKeyStream(dst, src []byte) { + for i := 0; i < len(src); i++ { + if x.outUsed == len(x.fre) { + x.b.Encrypt(x.fre, x.fre) + x.outUsed = 0 + } + + x.fre[x.outUsed] ^= src[i] + dst[i] = x.fre[x.outUsed] + x.outUsed++ + } +} + +type ocfbDecrypter struct { + b cipher.Block + fre []byte + outUsed int +} + +// NewOCFBDecrypter returns a cipher.Stream which decrypts data with OpenPGP's +// cipher feedback mode using the given cipher.Block. Prefix must be the first +// blockSize + 2 bytes of the ciphertext, where blockSize is the cipher.Block's +// block size. If an incorrect key is detected then nil is returned. On +// successful exit, blockSize+2 bytes of decrypted data are written into +// prefix. Resync determines if the "resynchronization step" from RFC 4880, +// 13.9 step 7 is performed. Different parts of OpenPGP vary on this point. +func NewOCFBDecrypter(block cipher.Block, prefix []byte, resync OCFBResyncOption) cipher.Stream { + blockSize := block.BlockSize() + if len(prefix) != blockSize+2 { + return nil + } + + x := &ocfbDecrypter{ + b: block, + fre: make([]byte, blockSize), + outUsed: 0, + } + prefixCopy := make([]byte, len(prefix)) + copy(prefixCopy, prefix) + + block.Encrypt(x.fre, x.fre) + for i := 0; i < blockSize; i++ { + prefixCopy[i] ^= x.fre[i] + } + + block.Encrypt(x.fre, prefix[:blockSize]) + prefixCopy[blockSize] ^= x.fre[0] + prefixCopy[blockSize+1] ^= x.fre[1] + + if prefixCopy[blockSize-2] != prefixCopy[blockSize] || + prefixCopy[blockSize-1] != prefixCopy[blockSize+1] { + return nil + } + + if resync { + block.Encrypt(x.fre, prefix[2:]) + } else { + x.fre[0] = prefix[blockSize] + x.fre[1] = prefix[blockSize+1] + x.outUsed = 2 + } + copy(prefix, prefixCopy) + return x +} + +func (x *ocfbDecrypter) XORKeyStream(dst, src []byte) { + for i := 0; i < len(src); i++ { + if x.outUsed == len(x.fre) { + x.b.Encrypt(x.fre, x.fre) + x.outUsed = 0 + } + + c := src[i] + dst[i] = x.fre[x.outUsed] ^ src[i] + x.fre[x.outUsed] = c + x.outUsed++ + } +} diff --git a/vendor/golang.org/x/crypto/openpgp/packet/one_pass_signature.go b/vendor/golang.org/x/crypto/openpgp/packet/one_pass_signature.go new file mode 100644 index 00000000..17135033 --- /dev/null +++ b/vendor/golang.org/x/crypto/openpgp/packet/one_pass_signature.go @@ -0,0 +1,73 @@ +// 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" + "encoding/binary" + "golang.org/x/crypto/openpgp/errors" + "golang.org/x/crypto/openpgp/s2k" + "io" + "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 error) { + var buf [13]byte + + _, err = readFull(r, buf[:]) + if err != nil { + return + } + if buf[0] != onePassSignatureVersion { + err = errors.UnsupportedError("one-pass-signature packet version " + strconv.Itoa(int(buf[0]))) + } + + var ok bool + ops.Hash, ok = s2k.HashIdToHash(buf[2]) + if !ok { + return errors.UnsupportedError("hash function: " + strconv.Itoa(int(buf[2]))) + } + + ops.SigType = SignatureType(buf[1]) + ops.PubKeyAlgo = PublicKeyAlgorithm(buf[3]) + ops.KeyId = binary.BigEndian.Uint64(buf[4:12]) + ops.IsLast = buf[12] != 0 + return +} + +// Serialize marshals the given OnePassSignature to w. +func (ops *OnePassSignature) Serialize(w io.Writer) 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 errors.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/vendor/golang.org/x/crypto/openpgp/packet/opaque.go b/vendor/golang.org/x/crypto/openpgp/packet/opaque.go new file mode 100644 index 00000000..456d807f --- /dev/null +++ b/vendor/golang.org/x/crypto/openpgp/packet/opaque.go @@ -0,0 +1,162 @@ +// Copyright 2012 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" + "io" + "io/ioutil" + + "golang.org/x/crypto/openpgp/errors" +) + +// OpaquePacket represents an OpenPGP packet as raw, unparsed data. This is +// useful for splitting and storing the original packet contents separately, +// handling unsupported packet types or accessing parts of the packet not yet +// implemented by this package. +type OpaquePacket struct { + // Packet type + Tag uint8 + // Reason why the packet was parsed opaquely + Reason error + // Binary contents of the packet data + Contents []byte +} + +func (op *OpaquePacket) parse(r io.Reader) (err error) { + op.Contents, err = ioutil.ReadAll(r) + return +} + +// Serialize marshals the packet to a writer in its original form, including +// the packet header. +func (op *OpaquePacket) Serialize(w io.Writer) (err error) { + err = serializeHeader(w, packetType(op.Tag), len(op.Contents)) + if err == nil { + _, err = w.Write(op.Contents) + } + return +} + +// Parse attempts to parse the opaque contents into a structure supported by +// this package. If the packet is not known then the result will be another +// OpaquePacket. +func (op *OpaquePacket) Parse() (p Packet, err error) { + hdr := bytes.NewBuffer(nil) + err = serializeHeader(hdr, packetType(op.Tag), len(op.Contents)) + if err != nil { + op.Reason = err + return op, err + } + p, err = Read(io.MultiReader(hdr, bytes.NewBuffer(op.Contents))) + if err != nil { + op.Reason = err + p = op + } + return +} + +// OpaqueReader reads OpaquePackets from an io.Reader. +type OpaqueReader struct { + r io.Reader +} + +func NewOpaqueReader(r io.Reader) *OpaqueReader { + return &OpaqueReader{r: r} +} + +// Read the next OpaquePacket. +func (or *OpaqueReader) Next() (op *OpaquePacket, err error) { + tag, _, contents, err := readHeader(or.r) + if err != nil { + return + } + op = &OpaquePacket{Tag: uint8(tag), Reason: err} + err = op.parse(contents) + if err != nil { + consumeAll(contents) + } + return +} + +// OpaqueSubpacket represents an unparsed OpenPGP subpacket, +// as found in signature and user attribute packets. +type OpaqueSubpacket struct { + SubType uint8 + Contents []byte +} + +// OpaqueSubpackets extracts opaque, unparsed OpenPGP subpackets from +// their byte representation. +func OpaqueSubpackets(contents []byte) (result []*OpaqueSubpacket, err error) { + var ( + subHeaderLen int + subPacket *OpaqueSubpacket + ) + for len(contents) > 0 { + subHeaderLen, subPacket, err = nextSubpacket(contents) + if err != nil { + break + } + result = append(result, subPacket) + contents = contents[subHeaderLen+len(subPacket.Contents):] + } + return +} + +func nextSubpacket(contents []byte) (subHeaderLen int, subPacket *OpaqueSubpacket, err error) { + // RFC 4880, section 5.2.3.1 + var subLen uint32 + if len(contents) < 1 { + goto Truncated + } + subPacket = &OpaqueSubpacket{} + switch { + case contents[0] < 192: + subHeaderLen = 2 // 1 length byte, 1 subtype byte + if len(contents) < subHeaderLen { + goto Truncated + } + subLen = uint32(contents[0]) + contents = contents[1:] + case contents[0] < 255: + subHeaderLen = 3 // 2 length bytes, 1 subtype + if len(contents) < subHeaderLen { + goto Truncated + } + subLen = uint32(contents[0]-192)<<8 + uint32(contents[1]) + 192 + contents = contents[2:] + default: + subHeaderLen = 6 // 5 length bytes, 1 subtype + if len(contents) < subHeaderLen { + goto Truncated + } + subLen = uint32(contents[1])<<24 | + uint32(contents[2])<<16 | + uint32(contents[3])<<8 | + uint32(contents[4]) + contents = contents[5:] + } + if subLen > uint32(len(contents)) || subLen == 0 { + goto Truncated + } + subPacket.SubType = contents[0] + subPacket.Contents = contents[1:subLen] + return +Truncated: + err = errors.StructuralError("subpacket truncated") + return +} + +func (osp *OpaqueSubpacket) Serialize(w io.Writer) (err error) { + buf := make([]byte, 6) + n := serializeSubpacketLength(buf, len(osp.Contents)+1) + buf[n] = osp.SubType + if _, err = w.Write(buf[:n+1]); err != nil { + return + } + _, err = w.Write(osp.Contents) + return +} diff --git a/vendor/golang.org/x/crypto/openpgp/packet/packet.go b/vendor/golang.org/x/crypto/openpgp/packet/packet.go new file mode 100644 index 00000000..3eded93f --- /dev/null +++ b/vendor/golang.org/x/crypto/openpgp/packet/packet.go @@ -0,0 +1,537 @@ +// 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 "golang.org/x/crypto/openpgp/packet" + +import ( + "bufio" + "crypto/aes" + "crypto/cipher" + "crypto/des" + "golang.org/x/crypto/cast5" + "golang.org/x/crypto/openpgp/errors" + "io" + "math/big" +) + +// 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 error) { + n, err = io.ReadFull(r, buf) + if err == io.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 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 error) { + for r.remaining == 0 { + if !r.isPartial { + return 0, io.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 == io.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 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() 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 error) { + if l.n <= 0 { + return 0, io.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 == io.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 error) { + var buf [4]byte + _, err = io.ReadFull(r, buf[:1]) + if err != nil { + return + } + if buf[0]&0x80 == 0 { + err = errors.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 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 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) error +} + +// consumeAll reads from the given Reader until error, returning the number of +// bytes read. +func consumeAll(r io.Reader) (n int64, err error) { + var m int + var buf [1024]byte + + for { + m, err = r.Read(buf[:]) + n += int64(m) + if err == io.EOF { + err = nil + return + } + if err != nil { + return + } + } +} + +// 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 + packetTypeUserAttribute packetType = 17 + packetTypeSymmetricallyEncryptedMDC packetType = 18 +) + +// peekVersion detects the version of a public key packet about to +// be read. A bufio.Reader at the original position of the io.Reader +// is returned. +func peekVersion(r io.Reader) (bufr *bufio.Reader, ver byte, err error) { + bufr = bufio.NewReader(r) + var verBuf []byte + if verBuf, err = bufr.Peek(1); err != nil { + return + } + ver = verBuf[0] + return +} + +// 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 error) { + tag, _, contents, err := readHeader(r) + if err != nil { + return + } + + switch tag { + case packetTypeEncryptedKey: + p = new(EncryptedKey) + case packetTypeSignature: + var version byte + // Detect signature version + if contents, version, err = peekVersion(contents); err != nil { + return + } + if version < 4 { + p = new(SignatureV3) + } else { + 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: + var version byte + if contents, version, err = peekVersion(contents); err != nil { + return + } + isSubkey := tag == packetTypePublicSubkey + if version < 4 { + p = &PublicKeyV3{IsSubkey: isSubkey} + } else { + p = &PublicKey{IsSubkey: isSubkey} + } + case packetTypeCompressed: + p = new(Compressed) + case packetTypeSymmetricallyEncrypted: + p = new(SymmetricallyEncrypted) + case packetTypeLiteralData: + p = new(LiteralData) + case packetTypeUserId: + p = new(UserId) + case packetTypeUserAttribute: + p = new(UserAttribute) + case packetTypeSymmetricallyEncryptedMDC: + se := new(SymmetricallyEncrypted) + se.MDC = true + p = se + default: + err = errors.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 + SigTypePrimaryKeyBinding = 0x19 + SigTypeDirectSignature = 0x1F + SigTypeKeyRevocation = 0x20 + SigTypeSubkeyRevocation = 0x28 +) + +// 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 + // RFC 6637, Section 5. + PubKeyAlgoECDH PublicKeyAlgorithm = 18 + PubKeyAlgoECDSA PublicKeyAlgorithm = 19 +) + +// 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, PubKeyAlgoECDSA: + 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 ( + Cipher3DES CipherFunction = 2 + 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 Cipher3DES: + return 24 + 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 Cipher3DES: + return des.BlockSize + 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 Cipher3DES: + block, _ = des.NewTripleDESCipher(key) + 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 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 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) error { + return writeMPI(w, uint16(i.BitLen()), i.Bytes()) +} + +// CompressionAlgo Represents the different compression algorithms +// supported by OpenPGP (except for BZIP2, which is not currently +// supported). See Section 9.3 of RFC 4880. +type CompressionAlgo uint8 + +const ( + CompressionNone CompressionAlgo = 0 + CompressionZIP CompressionAlgo = 1 + CompressionZLIB CompressionAlgo = 2 +) diff --git a/vendor/golang.org/x/crypto/openpgp/packet/private_key.go b/vendor/golang.org/x/crypto/openpgp/packet/private_key.go new file mode 100644 index 00000000..34734cc6 --- /dev/null +++ b/vendor/golang.org/x/crypto/openpgp/packet/private_key.go @@ -0,0 +1,380 @@ +// 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" + "crypto/cipher" + "crypto/dsa" + "crypto/ecdsa" + "crypto/rsa" + "crypto/sha1" + "io" + "io/ioutil" + "math/big" + "strconv" + "time" + + "golang.org/x/crypto/openpgp/elgamal" + "golang.org/x/crypto/openpgp/errors" + "golang.org/x/crypto/openpgp/s2k" +) + +// 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|dsa|ecdsa}.PrivateKey or a crypto.Signer. + sha1Checksum bool + iv []byte +} + +func NewRSAPrivateKey(currentTime time.Time, priv *rsa.PrivateKey) *PrivateKey { + pk := new(PrivateKey) + pk.PublicKey = *NewRSAPublicKey(currentTime, &priv.PublicKey) + pk.PrivateKey = priv + return pk +} + +func NewDSAPrivateKey(currentTime time.Time, priv *dsa.PrivateKey) *PrivateKey { + pk := new(PrivateKey) + pk.PublicKey = *NewDSAPublicKey(currentTime, &priv.PublicKey) + pk.PrivateKey = priv + return pk +} + +func NewElGamalPrivateKey(currentTime time.Time, priv *elgamal.PrivateKey) *PrivateKey { + pk := new(PrivateKey) + pk.PublicKey = *NewElGamalPublicKey(currentTime, &priv.PublicKey) + pk.PrivateKey = priv + return pk +} + +func NewECDSAPrivateKey(currentTime time.Time, priv *ecdsa.PrivateKey) *PrivateKey { + pk := new(PrivateKey) + pk.PublicKey = *NewECDSAPublicKey(currentTime, &priv.PublicKey) + pk.PrivateKey = priv + return pk +} + +// NewSignerPrivateKey creates a sign-only PrivateKey from a crypto.Signer that +// implements RSA or ECDSA. +func NewSignerPrivateKey(currentTime time.Time, signer crypto.Signer) *PrivateKey { + pk := new(PrivateKey) + switch pubkey := signer.Public().(type) { + case rsa.PublicKey: + pk.PublicKey = *NewRSAPublicKey(currentTime, &pubkey) + pk.PubKeyAlgo = PubKeyAlgoRSASignOnly + case ecdsa.PublicKey: + pk.PublicKey = *NewECDSAPublicKey(currentTime, &pubkey) + default: + panic("openpgp: unknown crypto.Signer type in NewSignerPrivateKey") + } + pk.PrivateKey = signer + return pk +} + +func (pk *PrivateKey) parse(r io.Reader) (err 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 errors.UnsupportedError("deprecated s2k function in private key") + } + + if pk.Encrypted { + blockSize := pk.cipher.blockSize() + if blockSize == 0 { + return errors.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 { + var h uint16 + for _, b := range d { + h += uint16(b) + } + return h +} + +func (pk *PrivateKey) Serialize(w io.Writer) (err 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) + case *dsa.PrivateKey: + err = serializeDSAPrivateKey(privateKeyBuf, priv) + case *elgamal.PrivateKey: + err = serializeElGamalPrivateKey(privateKeyBuf, priv) + case *ecdsa.PrivateKey: + err = serializeECDSAPrivateKey(privateKeyBuf, priv) + default: + err = errors.InvalidArgumentError("unknown private key type") + } + 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) 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) +} + +func serializeDSAPrivateKey(w io.Writer, priv *dsa.PrivateKey) error { + return writeBig(w, priv.X) +} + +func serializeElGamalPrivateKey(w io.Writer, priv *elgamal.PrivateKey) error { + return writeBig(w, priv.X) +} + +func serializeECDSAPrivateKey(w io.Writer, priv *ecdsa.PrivateKey) error { + return writeBig(w, priv.D) +} + +// Decrypt decrypts an encrypted private key using a passphrase. +func (pk *PrivateKey) Decrypt(passphrase []byte) 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 := make([]byte, len(pk.encryptedData)) + cfb.XORKeyStream(data, pk.encryptedData) + + if pk.sha1Checksum { + if len(data) < sha1.Size { + return errors.StructuralError("truncated private key data") + } + h := sha1.New() + h.Write(data[:len(data)-sha1.Size]) + sum := h.Sum(nil) + if !bytes.Equal(sum, data[len(data)-sha1.Size:]) { + return errors.StructuralError("private key checksum failure") + } + data = data[:len(data)-sha1.Size] + } else { + if len(data) < 2 { + return errors.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 errors.StructuralError("private key checksum failure") + } + data = data[:len(data)-2] + } + + return pk.parsePrivateKey(data) +} + +func (pk *PrivateKey) parsePrivateKey(data []byte) (err 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) + case PubKeyAlgoECDSA: + return pk.parseECDSAPrivateKey(data) + } + panic("impossible") +} + +func (pk *PrivateKey) parseRSAPrivateKey(data []byte) (err 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) + if err := rsaPriv.Validate(); err != nil { + return err + } + rsaPriv.Precompute() + pk.PrivateKey = rsaPriv + pk.Encrypted = false + pk.encryptedData = nil + + return nil +} + +func (pk *PrivateKey) parseDSAPrivateKey(data []byte) (err 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 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 +} + +func (pk *PrivateKey) parseECDSAPrivateKey(data []byte) (err error) { + ecdsaPub := pk.PublicKey.PublicKey.(*ecdsa.PublicKey) + + buf := bytes.NewBuffer(data) + d, _, err := readMPI(buf) + if err != nil { + return + } + + pk.PrivateKey = &ecdsa.PrivateKey{ + PublicKey: *ecdsaPub, + D: new(big.Int).SetBytes(d), + } + pk.Encrypted = false + pk.encryptedData = nil + + return nil +} diff --git a/vendor/golang.org/x/crypto/openpgp/packet/public_key.go b/vendor/golang.org/x/crypto/openpgp/packet/public_key.go new file mode 100644 index 00000000..ead26233 --- /dev/null +++ b/vendor/golang.org/x/crypto/openpgp/packet/public_key.go @@ -0,0 +1,748 @@ +// 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" + "crypto/dsa" + "crypto/ecdsa" + "crypto/elliptic" + "crypto/rsa" + "crypto/sha1" + _ "crypto/sha256" + _ "crypto/sha512" + "encoding/binary" + "fmt" + "hash" + "io" + "math/big" + "strconv" + "time" + + "golang.org/x/crypto/openpgp/elgamal" + "golang.org/x/crypto/openpgp/errors" +) + +var ( + // NIST curve P-256 + oidCurveP256 []byte = []byte{0x2A, 0x86, 0x48, 0xCE, 0x3D, 0x03, 0x01, 0x07} + // NIST curve P-384 + oidCurveP384 []byte = []byte{0x2B, 0x81, 0x04, 0x00, 0x22} + // NIST curve P-521 + oidCurveP521 []byte = []byte{0x2B, 0x81, 0x04, 0x00, 0x23} +) + +const maxOIDLength = 8 + +// ecdsaKey stores the algorithm-specific fields for ECDSA keys. +// as defined in RFC 6637, Section 9. +type ecdsaKey struct { + // oid contains the OID byte sequence identifying the elliptic curve used + oid []byte + // p contains the elliptic curve point that represents the public key + p parsedMPI +} + +// parseOID reads the OID for the curve as defined in RFC 6637, Section 9. +func parseOID(r io.Reader) (oid []byte, err error) { + buf := make([]byte, maxOIDLength) + if _, err = readFull(r, buf[:1]); err != nil { + return + } + oidLen := buf[0] + if int(oidLen) > len(buf) { + err = errors.UnsupportedError("invalid oid length: " + strconv.Itoa(int(oidLen))) + return + } + oid = buf[:oidLen] + _, err = readFull(r, oid) + return +} + +func (f *ecdsaKey) parse(r io.Reader) (err error) { + if f.oid, err = parseOID(r); err != nil { + return err + } + f.p.bytes, f.p.bitLength, err = readMPI(r) + return +} + +func (f *ecdsaKey) serialize(w io.Writer) (err error) { + buf := make([]byte, maxOIDLength+1) + buf[0] = byte(len(f.oid)) + copy(buf[1:], f.oid) + if _, err = w.Write(buf[:len(f.oid)+1]); err != nil { + return + } + return writeMPIs(w, f.p) +} + +func (f *ecdsaKey) newECDSA() (*ecdsa.PublicKey, error) { + var c elliptic.Curve + if bytes.Equal(f.oid, oidCurveP256) { + c = elliptic.P256() + } else if bytes.Equal(f.oid, oidCurveP384) { + c = elliptic.P384() + } else if bytes.Equal(f.oid, oidCurveP521) { + c = elliptic.P521() + } else { + return nil, errors.UnsupportedError(fmt.Sprintf("unsupported oid: %x", f.oid)) + } + x, y := elliptic.Unmarshal(c, f.p.bytes) + if x == nil { + return nil, errors.UnsupportedError("failed to parse EC point") + } + return &ecdsa.PublicKey{Curve: c, X: x, Y: y}, nil +} + +func (f *ecdsaKey) byteLen() int { + return 1 + len(f.oid) + 2 + len(f.p.bytes) +} + +type kdfHashFunction byte +type kdfAlgorithm byte + +// ecdhKdf stores key derivation function parameters +// used for ECDH encryption. See RFC 6637, Section 9. +type ecdhKdf struct { + KdfHash kdfHashFunction + KdfAlgo kdfAlgorithm +} + +func (f *ecdhKdf) parse(r io.Reader) (err error) { + buf := make([]byte, 1) + if _, err = readFull(r, buf); err != nil { + return + } + kdfLen := int(buf[0]) + if kdfLen < 3 { + return errors.UnsupportedError("Unsupported ECDH KDF length: " + strconv.Itoa(kdfLen)) + } + buf = make([]byte, kdfLen) + if _, err = readFull(r, buf); err != nil { + return + } + reserved := int(buf[0]) + f.KdfHash = kdfHashFunction(buf[1]) + f.KdfAlgo = kdfAlgorithm(buf[2]) + if reserved != 0x01 { + return errors.UnsupportedError("Unsupported KDF reserved field: " + strconv.Itoa(reserved)) + } + return +} + +func (f *ecdhKdf) serialize(w io.Writer) (err error) { + buf := make([]byte, 4) + // See RFC 6637, Section 9, Algorithm-Specific Fields for ECDH keys. + buf[0] = byte(0x03) // Length of the following fields + buf[1] = byte(0x01) // Reserved for future extensions, must be 1 for now + buf[2] = byte(f.KdfHash) + buf[3] = byte(f.KdfAlgo) + _, err = w.Write(buf[:]) + return +} + +func (f *ecdhKdf) byteLen() int { + return 4 +} + +// PublicKey represents an OpenPGP public key. See RFC 4880, section 5.5.2. +type PublicKey struct { + CreationTime time.Time + PubKeyAlgo PublicKeyAlgorithm + PublicKey interface{} // *rsa.PublicKey, *dsa.PublicKey or *ecdsa.PublicKey + Fingerprint [20]byte + KeyId uint64 + IsSubkey bool + + n, e, p, q, g, y parsedMPI + + // RFC 6637 fields + ec *ecdsaKey + ecdh *ecdhKdf +} + +// signingKey provides a convenient abstraction over signature verification +// for v3 and v4 public keys. +type signingKey interface { + SerializeSignaturePrefix(io.Writer) + serializeWithoutHeaders(io.Writer) error +} + +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(creationTime time.Time, pub *rsa.PublicKey) *PublicKey { + pk := &PublicKey{ + CreationTime: creationTime, + PubKeyAlgo: PubKeyAlgoRSA, + PublicKey: pub, + n: fromBig(pub.N), + e: fromBig(big.NewInt(int64(pub.E))), + } + + pk.setFingerPrintAndKeyId() + return pk +} + +// NewDSAPublicKey returns a PublicKey that wraps the given dsa.PublicKey. +func NewDSAPublicKey(creationTime time.Time, pub *dsa.PublicKey) *PublicKey { + pk := &PublicKey{ + CreationTime: creationTime, + PubKeyAlgo: PubKeyAlgoDSA, + PublicKey: pub, + p: fromBig(pub.P), + q: fromBig(pub.Q), + g: fromBig(pub.G), + y: fromBig(pub.Y), + } + + pk.setFingerPrintAndKeyId() + return pk +} + +// NewElGamalPublicKey returns a PublicKey that wraps the given elgamal.PublicKey. +func NewElGamalPublicKey(creationTime time.Time, pub *elgamal.PublicKey) *PublicKey { + pk := &PublicKey{ + CreationTime: creationTime, + PubKeyAlgo: PubKeyAlgoElGamal, + PublicKey: pub, + p: fromBig(pub.P), + g: fromBig(pub.G), + y: fromBig(pub.Y), + } + + pk.setFingerPrintAndKeyId() + return pk +} + +func NewECDSAPublicKey(creationTime time.Time, pub *ecdsa.PublicKey) *PublicKey { + pk := &PublicKey{ + CreationTime: creationTime, + PubKeyAlgo: PubKeyAlgoECDSA, + PublicKey: pub, + ec: new(ecdsaKey), + } + + switch pub.Curve { + case elliptic.P256(): + pk.ec.oid = oidCurveP256 + case elliptic.P384(): + pk.ec.oid = oidCurveP384 + case elliptic.P521(): + pk.ec.oid = oidCurveP521 + default: + panic("unknown elliptic curve") + } + + pk.ec.p.bytes = elliptic.Marshal(pub.Curve, pub.X, pub.Y) + pk.ec.p.bitLength = uint16(8 * len(pk.ec.p.bytes)) + + pk.setFingerPrintAndKeyId() + return pk +} + +func (pk *PublicKey) parse(r io.Reader) (err error) { + // RFC 4880, section 5.5.2 + var buf [6]byte + _, err = readFull(r, buf[:]) + if err != nil { + return + } + if buf[0] != 4 { + return errors.UnsupportedError("public key version") + } + pk.CreationTime = time.Unix(int64(uint32(buf[1])<<24|uint32(buf[2])<<16|uint32(buf[3])<<8|uint32(buf[4])), 0) + 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) + case PubKeyAlgoECDSA: + pk.ec = new(ecdsaKey) + if err = pk.ec.parse(r); err != nil { + return err + } + pk.PublicKey, err = pk.ec.newECDSA() + case PubKeyAlgoECDH: + pk.ec = new(ecdsaKey) + if err = pk.ec.parse(r); err != nil { + return + } + pk.ecdh = new(ecdhKdf) + if err = pk.ecdh.parse(r); err != nil { + return + } + // The ECDH key is stored in an ecdsa.PublicKey for convenience. + pk.PublicKey, err = pk.ec.newECDSA() + default: + err = errors.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(nil)) + 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 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 = errors.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 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 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 io.Writer) { + 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)) + case PubKeyAlgoECDSA: + pLength += uint16(pk.ec.byteLen()) + case PubKeyAlgoECDH: + pLength += uint16(pk.ec.byteLen()) + pLength += uint16(pk.ecdh.byteLen()) + 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 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) + case PubKeyAlgoECDSA: + length += pk.ec.byteLen() + case PubKeyAlgoECDH: + length += pk.ec.byteLen() + length += pk.ecdh.byteLen() + 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 error) { + var buf [6]byte + buf[0] = 4 + t := uint32(pk.CreationTime.Unix()) + buf[1] = byte(t >> 24) + buf[2] = byte(t >> 16) + buf[3] = byte(t >> 8) + buf[4] = byte(t) + 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) + case PubKeyAlgoECDSA: + return pk.ec.serialize(w) + case PubKeyAlgoECDH: + if err = pk.ec.serialize(w); err != nil { + return + } + return pk.ecdh.serialize(w) + } + return errors.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 error) { + if !pk.CanSign() { + return errors.InvalidArgumentError("public key cannot generate signatures") + } + + signed.Write(sig.HashSuffix) + hashBytes := signed.Sum(nil) + + if hashBytes[0] != sig.HashTag[0] || hashBytes[1] != sig.HashTag[1] { + return errors.SignatureError("hash tag doesn't match") + } + + if pk.PubKeyAlgo != sig.PubKeyAlgo { + return errors.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 errors.SignatureError("RSA verification failure") + } + return nil + case PubKeyAlgoDSA: + dsaPublicKey, _ := pk.PublicKey.(*dsa.PublicKey) + // Need to truncate hashBytes to match FIPS 186-3 section 4.6. + subgroupSize := (dsaPublicKey.Q.BitLen() + 7) / 8 + if len(hashBytes) > subgroupSize { + hashBytes = hashBytes[:subgroupSize] + } + if !dsa.Verify(dsaPublicKey, hashBytes, new(big.Int).SetBytes(sig.DSASigR.bytes), new(big.Int).SetBytes(sig.DSASigS.bytes)) { + return errors.SignatureError("DSA verification failure") + } + return nil + case PubKeyAlgoECDSA: + ecdsaPublicKey := pk.PublicKey.(*ecdsa.PublicKey) + if !ecdsa.Verify(ecdsaPublicKey, hashBytes, new(big.Int).SetBytes(sig.ECDSASigR.bytes), new(big.Int).SetBytes(sig.ECDSASigS.bytes)) { + return errors.SignatureError("ECDSA verification failure") + } + return nil + default: + return errors.SignatureError("Unsupported public key algorithm used in signature") + } +} + +// VerifySignatureV3 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) VerifySignatureV3(signed hash.Hash, sig *SignatureV3) (err error) { + if !pk.CanSign() { + return errors.InvalidArgumentError("public key cannot generate signatures") + } + + suffix := make([]byte, 5) + suffix[0] = byte(sig.SigType) + binary.BigEndian.PutUint32(suffix[1:], uint32(sig.CreationTime.Unix())) + signed.Write(suffix) + hashBytes := signed.Sum(nil) + + if hashBytes[0] != sig.HashTag[0] || hashBytes[1] != sig.HashTag[1] { + return errors.SignatureError("hash tag doesn't match") + } + + if pk.PubKeyAlgo != sig.PubKeyAlgo { + return errors.InvalidArgumentError("public key and signature use different algorithms") + } + + switch pk.PubKeyAlgo { + case PubKeyAlgoRSA, PubKeyAlgoRSASignOnly: + rsaPublicKey := pk.PublicKey.(*rsa.PublicKey) + if err = rsa.VerifyPKCS1v15(rsaPublicKey, sig.Hash, hashBytes, sig.RSASignature.bytes); err != nil { + return errors.SignatureError("RSA verification failure") + } + return + case PubKeyAlgoDSA: + dsaPublicKey := pk.PublicKey.(*dsa.PublicKey) + // Need to truncate hashBytes to match FIPS 186-3 section 4.6. + subgroupSize := (dsaPublicKey.Q.BitLen() + 7) / 8 + if len(hashBytes) > subgroupSize { + hashBytes = hashBytes[:subgroupSize] + } + if !dsa.Verify(dsaPublicKey, hashBytes, new(big.Int).SetBytes(sig.DSASigR.bytes), new(big.Int).SetBytes(sig.DSASigS.bytes)) { + return errors.SignatureError("DSA verification failure") + } + return nil + default: + panic("shouldn't happen") + } +} + +// 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 signingKey, hashFunc crypto.Hash) (h hash.Hash, err error) { + if !hashFunc.Available() { + return nil, errors.UnsupportedError("hash function") + } + h = hashFunc.New() + + // 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) error { + h, err := keySignatureHash(pk, signed, sig.Hash) + if err != nil { + return err + } + if err = pk.VerifySignature(h, sig); err != nil { + return err + } + + if sig.FlagSign { + // Signing subkeys must be cross-signed. See + // https://www.gnupg.org/faq/subkey-cross-certify.html. + if sig.EmbeddedSignature == nil { + return errors.StructuralError("signing subkey is missing cross-signature") + } + // Verify the cross-signature. This is calculated over the same + // data as the main signature, so we cannot just recursively + // call signed.VerifyKeySignature(...) + if h, err = keySignatureHash(pk, signed, sig.EmbeddedSignature.Hash); err != nil { + return errors.StructuralError("error while hashing for cross-signature: " + err.Error()) + } + if err := signed.VerifySignature(h, sig.EmbeddedSignature); err != nil { + return errors.StructuralError("error while verifying cross-signature: " + err.Error()) + } + } + + return nil +} + +func keyRevocationHash(pk signingKey, hashFunc crypto.Hash) (h hash.Hash, err error) { + if !hashFunc.Available() { + return nil, errors.UnsupportedError("hash function") + } + h = hashFunc.New() + + // RFC 4880, section 5.2.4 + pk.SerializeSignaturePrefix(h) + pk.serializeWithoutHeaders(h) + + return +} + +// VerifyRevocationSignature returns nil iff sig is a valid signature, made by this +// public key. +func (pk *PublicKey) VerifyRevocationSignature(sig *Signature) (err error) { + h, err := keyRevocationHash(pk, sig.Hash) + 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, hashFunc crypto.Hash) (h hash.Hash, err error) { + if !hashFunc.Available() { + return nil, errors.UnsupportedError("hash function") + } + h = hashFunc.New() + + // 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, that id is the identity of pub. +func (pk *PublicKey) VerifyUserIdSignature(id string, pub *PublicKey, sig *Signature) (err error) { + h, err := userIdSignatureHash(id, pub, sig.Hash) + if err != nil { + return err + } + return pk.VerifySignature(h, sig) +} + +// VerifyUserIdSignatureV3 returns nil iff sig is a valid signature, made by this +// public key, that id is the identity of pub. +func (pk *PublicKey) VerifyUserIdSignatureV3(id string, pub *PublicKey, sig *SignatureV3) (err error) { + h, err := userIdSignatureV3Hash(id, pub, sig.Hash) + if err != nil { + return err + } + return pk.VerifySignatureV3(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 error) { + for _, mpi := range mpis { + err = writeMPI(w, mpi.bitLength, mpi.bytes) + if err != nil { + return + } + } + return +} + +// BitLength returns the bit length for the given public key. +func (pk *PublicKey) BitLength() (bitLength uint16, err error) { + switch pk.PubKeyAlgo { + case PubKeyAlgoRSA, PubKeyAlgoRSAEncryptOnly, PubKeyAlgoRSASignOnly: + bitLength = pk.n.bitLength + case PubKeyAlgoDSA: + bitLength = pk.p.bitLength + case PubKeyAlgoElGamal: + bitLength = pk.p.bitLength + default: + err = errors.InvalidArgumentError("bad public-key algorithm") + } + return +} diff --git a/vendor/golang.org/x/crypto/openpgp/packet/public_key_v3.go b/vendor/golang.org/x/crypto/openpgp/packet/public_key_v3.go new file mode 100644 index 00000000..5daf7b6c --- /dev/null +++ b/vendor/golang.org/x/crypto/openpgp/packet/public_key_v3.go @@ -0,0 +1,279 @@ +// Copyright 2013 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/md5" + "crypto/rsa" + "encoding/binary" + "fmt" + "hash" + "io" + "math/big" + "strconv" + "time" + + "golang.org/x/crypto/openpgp/errors" +) + +// PublicKeyV3 represents older, version 3 public keys. These keys are less secure and +// should not be used for signing or encrypting. They are supported here only for +// parsing version 3 key material and validating signatures. +// See RFC 4880, section 5.5.2. +type PublicKeyV3 struct { + CreationTime time.Time + DaysToExpire uint16 + PubKeyAlgo PublicKeyAlgorithm + PublicKey *rsa.PublicKey + Fingerprint [16]byte + KeyId uint64 + IsSubkey bool + + n, e parsedMPI +} + +// newRSAPublicKeyV3 returns a PublicKey that wraps the given rsa.PublicKey. +// Included here for testing purposes only. RFC 4880, section 5.5.2: +// "an implementation MUST NOT generate a V3 key, but MAY accept it." +func newRSAPublicKeyV3(creationTime time.Time, pub *rsa.PublicKey) *PublicKeyV3 { + pk := &PublicKeyV3{ + CreationTime: creationTime, + PublicKey: pub, + n: fromBig(pub.N), + e: fromBig(big.NewInt(int64(pub.E))), + } + + pk.setFingerPrintAndKeyId() + return pk +} + +func (pk *PublicKeyV3) parse(r io.Reader) (err error) { + // RFC 4880, section 5.5.2 + var buf [8]byte + if _, err = readFull(r, buf[:]); err != nil { + return + } + if buf[0] < 2 || buf[0] > 3 { + return errors.UnsupportedError("public key version") + } + pk.CreationTime = time.Unix(int64(uint32(buf[1])<<24|uint32(buf[2])<<16|uint32(buf[3])<<8|uint32(buf[4])), 0) + pk.DaysToExpire = binary.BigEndian.Uint16(buf[5:7]) + pk.PubKeyAlgo = PublicKeyAlgorithm(buf[7]) + switch pk.PubKeyAlgo { + case PubKeyAlgoRSA, PubKeyAlgoRSAEncryptOnly, PubKeyAlgoRSASignOnly: + err = pk.parseRSA(r) + default: + err = errors.UnsupportedError("public key type: " + strconv.Itoa(int(pk.PubKeyAlgo))) + } + if err != nil { + return + } + + pk.setFingerPrintAndKeyId() + return +} + +func (pk *PublicKeyV3) setFingerPrintAndKeyId() { + // RFC 4880, section 12.2 + fingerPrint := md5.New() + fingerPrint.Write(pk.n.bytes) + fingerPrint.Write(pk.e.bytes) + fingerPrint.Sum(pk.Fingerprint[:0]) + pk.KeyId = binary.BigEndian.Uint64(pk.n.bytes[len(pk.n.bytes)-8:]) +} + +// parseRSA parses RSA public key material from the given Reader. See RFC 4880, +// section 5.5.2. +func (pk *PublicKeyV3) parseRSA(r io.Reader) (err error) { + if pk.n.bytes, pk.n.bitLength, err = readMPI(r); err != nil { + return + } + if pk.e.bytes, pk.e.bitLength, err = readMPI(r); err != nil { + return + } + + // RFC 4880 Section 12.2 requires the low 8 bytes of the + // modulus to form the key id. + if len(pk.n.bytes) < 8 { + return errors.StructuralError("v3 public key modulus is too short") + } + if len(pk.e.bytes) > 3 { + err = errors.UnsupportedError("large public exponent") + return + } + rsa := &rsa.PublicKey{N: new(big.Int).SetBytes(pk.n.bytes)} + for i := 0; i < len(pk.e.bytes); i++ { + rsa.E <<= 8 + rsa.E |= int(pk.e.bytes[i]) + } + pk.PublicKey = rsa + 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 *PublicKeyV3) SerializeSignaturePrefix(w io.Writer) { + var pLength uint16 + switch pk.PubKeyAlgo { + case PubKeyAlgoRSA, PubKeyAlgoRSAEncryptOnly, PubKeyAlgoRSASignOnly: + pLength += 2 + uint16(len(pk.n.bytes)) + pLength += 2 + uint16(len(pk.e.bytes)) + default: + panic("unknown public key algorithm") + } + pLength += 6 + w.Write([]byte{0x99, byte(pLength >> 8), byte(pLength)}) + return +} + +func (pk *PublicKeyV3) Serialize(w io.Writer) (err error) { + length := 8 // 8 byte header + + switch pk.PubKeyAlgo { + case PubKeyAlgoRSA, PubKeyAlgoRSAEncryptOnly, PubKeyAlgoRSASignOnly: + length += 2 + len(pk.n.bytes) + length += 2 + len(pk.e.bytes) + default: + panic("unknown public key algorithm") + } + + packetType := packetTypePublicKey + if pk.IsSubkey { + packetType = packetTypePublicSubkey + } + if err = serializeHeader(w, packetType, length); 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 *PublicKeyV3) serializeWithoutHeaders(w io.Writer) (err error) { + var buf [8]byte + // Version 3 + buf[0] = 3 + // Creation time + t := uint32(pk.CreationTime.Unix()) + buf[1] = byte(t >> 24) + buf[2] = byte(t >> 16) + buf[3] = byte(t >> 8) + buf[4] = byte(t) + // Days to expire + buf[5] = byte(pk.DaysToExpire >> 8) + buf[6] = byte(pk.DaysToExpire) + // Public key algorithm + buf[7] = byte(pk.PubKeyAlgo) + + if _, err = w.Write(buf[:]); err != nil { + return + } + + switch pk.PubKeyAlgo { + case PubKeyAlgoRSA, PubKeyAlgoRSAEncryptOnly, PubKeyAlgoRSASignOnly: + return writeMPIs(w, pk.n, pk.e) + } + return errors.InvalidArgumentError("bad public-key algorithm") +} + +// CanSign returns true iff this public key can generate signatures +func (pk *PublicKeyV3) CanSign() bool { + return pk.PubKeyAlgo != PubKeyAlgoRSAEncryptOnly +} + +// VerifySignatureV3 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 *PublicKeyV3) VerifySignatureV3(signed hash.Hash, sig *SignatureV3) (err error) { + if !pk.CanSign() { + return errors.InvalidArgumentError("public key cannot generate signatures") + } + + suffix := make([]byte, 5) + suffix[0] = byte(sig.SigType) + binary.BigEndian.PutUint32(suffix[1:], uint32(sig.CreationTime.Unix())) + signed.Write(suffix) + hashBytes := signed.Sum(nil) + + if hashBytes[0] != sig.HashTag[0] || hashBytes[1] != sig.HashTag[1] { + return errors.SignatureError("hash tag doesn't match") + } + + if pk.PubKeyAlgo != sig.PubKeyAlgo { + return errors.InvalidArgumentError("public key and signature use different algorithms") + } + + switch pk.PubKeyAlgo { + case PubKeyAlgoRSA, PubKeyAlgoRSASignOnly: + if err = rsa.VerifyPKCS1v15(pk.PublicKey, sig.Hash, hashBytes, sig.RSASignature.bytes); err != nil { + return errors.SignatureError("RSA verification failure") + } + return + default: + // V3 public keys only support RSA. + panic("shouldn't happen") + } +} + +// VerifyUserIdSignatureV3 returns nil iff sig is a valid signature, made by this +// public key, that id is the identity of pub. +func (pk *PublicKeyV3) VerifyUserIdSignatureV3(id string, pub *PublicKeyV3, sig *SignatureV3) (err error) { + h, err := userIdSignatureV3Hash(id, pk, sig.Hash) + if err != nil { + return err + } + return pk.VerifySignatureV3(h, sig) +} + +// VerifyKeySignatureV3 returns nil iff sig is a valid signature, made by this +// public key, of signed. +func (pk *PublicKeyV3) VerifyKeySignatureV3(signed *PublicKeyV3, sig *SignatureV3) (err error) { + h, err := keySignatureHash(pk, signed, sig.Hash) + if err != nil { + return err + } + return pk.VerifySignatureV3(h, sig) +} + +// userIdSignatureV3Hash returns a Hash of the message that needs to be signed +// to assert that pk is a valid key for id. +func userIdSignatureV3Hash(id string, pk signingKey, hfn crypto.Hash) (h hash.Hash, err error) { + if !hfn.Available() { + return nil, errors.UnsupportedError("hash function") + } + h = hfn.New() + + // RFC 4880, section 5.2.4 + pk.SerializeSignaturePrefix(h) + pk.serializeWithoutHeaders(h) + + h.Write([]byte(id)) + + return +} + +// KeyIdString returns the public key's fingerprint in capital hex +// (e.g. "6C7EE1B8621CC013"). +func (pk *PublicKeyV3) KeyIdString() string { + return fmt.Sprintf("%X", pk.KeyId) +} + +// KeyIdShortString returns the short form of public key's fingerprint +// in capital hex, as shown by gpg --list-keys (e.g. "621CC013"). +func (pk *PublicKeyV3) KeyIdShortString() string { + return fmt.Sprintf("%X", pk.KeyId&0xFFFFFFFF) +} + +// BitLength returns the bit length for the given public key. +func (pk *PublicKeyV3) BitLength() (bitLength uint16, err error) { + switch pk.PubKeyAlgo { + case PubKeyAlgoRSA, PubKeyAlgoRSAEncryptOnly, PubKeyAlgoRSASignOnly: + bitLength = pk.n.bitLength + default: + err = errors.InvalidArgumentError("bad public-key algorithm") + } + return +} diff --git a/vendor/golang.org/x/crypto/openpgp/packet/reader.go b/vendor/golang.org/x/crypto/openpgp/packet/reader.go new file mode 100644 index 00000000..34bc7c61 --- /dev/null +++ b/vendor/golang.org/x/crypto/openpgp/packet/reader.go @@ -0,0 +1,76 @@ +// 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 ( + "golang.org/x/crypto/openpgp/errors" + "io" +) + +// 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 +} + +// New io.Readers are pushed when a compressed or encrypted packet is processed +// and recursively treated as a new source of packets. However, a carefully +// crafted packet can trigger an infinite recursive sequence of packets. See +// http://mumble.net/~campbell/misc/pgp-quine +// https://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2013-4402 +// This constant limits the number of recursive packets that may be pushed. +const maxReaders = 32 + +// 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 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 == io.EOF { + r.readers = r.readers[:len(r.readers)-1] + continue + } + if _, ok := err.(errors.UnknownPacketTypeError); !ok { + return nil, err + } + } + + return nil, io.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. Push returns a StructuralError +// if pushing the reader would exceed the maximum recursion level, otherwise it +// returns nil. +func (r *Reader) Push(reader io.Reader) (err error) { + if len(r.readers) >= maxReaders { + return errors.StructuralError("too many layers of packets") + } + r.readers = append(r.readers, reader) + return nil +} + +// 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/vendor/golang.org/x/crypto/openpgp/packet/signature.go b/vendor/golang.org/x/crypto/openpgp/packet/signature.go new file mode 100644 index 00000000..6ce0cbed --- /dev/null +++ b/vendor/golang.org/x/crypto/openpgp/packet/signature.go @@ -0,0 +1,731 @@ +// 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" + "crypto/dsa" + "crypto/ecdsa" + "encoding/asn1" + "encoding/binary" + "hash" + "io" + "math/big" + "strconv" + "time" + + "golang.org/x/crypto/openpgp/errors" + "golang.org/x/crypto/openpgp/s2k" +) + +const ( + // See RFC 4880, section 5.2.3.21 for details. + KeyFlagCertify = 1 << iota + KeyFlagSign + KeyFlagEncryptCommunications + KeyFlagEncryptStorage +) + +// 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 time.Time + + RSASignature parsedMPI + DSASigR, DSASigS parsedMPI + ECDSASigR, ECDSASigS 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 + + // RevocationReason is set if this signature has been revoked. + // See RFC 4880, section 5.2.3.23 for details. + RevocationReason *uint8 + RevocationReasonText string + + // MDC is set if this signature has a feature packet that indicates + // support for MDC subpackets. + MDC bool + + // EmbeddedSignature, if non-nil, is a signature of the parent key, by + // this key. This prevents an attacker from claiming another's signing + // subkey as their own. + EmbeddedSignature *Signature + + outSubpackets []outputSubpacket +} + +func (sig *Signature) parse(r io.Reader) (err error) { + // RFC 4880, section 5.2.3 + var buf [5]byte + _, err = readFull(r, buf[:1]) + if err != nil { + return + } + if buf[0] != 4 { + err = errors.UnsupportedError("signature packet version " + strconv.Itoa(int(buf[0]))) + return + } + + _, err = readFull(r, buf[:5]) + if err != nil { + return + } + sig.SigType = SignatureType(buf[0]) + sig.PubKeyAlgo = PublicKeyAlgorithm(buf[1]) + switch sig.PubKeyAlgo { + case PubKeyAlgoRSA, PubKeyAlgoRSASignOnly, PubKeyAlgoDSA, PubKeyAlgoECDSA: + default: + err = errors.UnsupportedError("public key algorithm " + strconv.Itoa(int(sig.PubKeyAlgo))) + return + } + + var ok bool + sig.Hash, ok = s2k.HashIdToHash(buf[2]) + if !ok { + return errors.UnsupportedError("hash function " + strconv.Itoa(int(buf[2]))) + } + + hashedSubpacketsLength := int(buf[3])<<8 | int(buf[4]) + l := 6 + hashedSubpacketsLength + sig.HashSuffix = make([]byte, l+6) + sig.HashSuffix[0] = 4 + copy(sig.HashSuffix[1:], buf[:5]) + hashedSubpackets := sig.HashSuffix[6:l] + _, err = readFull(r, hashedSubpackets) + if err != nil { + return + } + // See RFC 4880, section 5.2.4 + trailer := sig.HashSuffix[l:] + trailer[0] = 4 + trailer[1] = 0xff + trailer[2] = uint8(l >> 24) + trailer[3] = uint8(l >> 16) + trailer[4] = uint8(l >> 8) + trailer[5] = uint8(l) + + err = parseSignatureSubpackets(sig, hashedSubpackets, true) + if err != nil { + return + } + + _, err = readFull(r, buf[:2]) + if err != nil { + return + } + unhashedSubpacketsLength := int(buf[0])<<8 | int(buf[1]) + unhashedSubpackets := make([]byte, unhashedSubpacketsLength) + _, err = readFull(r, unhashedSubpackets) + if err != nil { + return + } + err = parseSignatureSubpackets(sig, unhashedSubpackets, false) + if err != nil { + return + } + + _, err = readFull(r, sig.HashTag[:2]) + if err != nil { + return + } + + switch sig.PubKeyAlgo { + case PubKeyAlgoRSA, PubKeyAlgoRSASignOnly: + sig.RSASignature.bytes, sig.RSASignature.bitLength, err = readMPI(r) + case PubKeyAlgoDSA: + sig.DSASigR.bytes, sig.DSASigR.bitLength, err = readMPI(r) + if err == nil { + sig.DSASigS.bytes, sig.DSASigS.bitLength, err = readMPI(r) + } + case PubKeyAlgoECDSA: + sig.ECDSASigR.bytes, sig.ECDSASigR.bitLength, err = readMPI(r) + if err == nil { + sig.ECDSASigS.bytes, sig.ECDSASigS.bitLength, err = readMPI(r) + } + default: + panic("unreachable") + } + return +} + +// 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 error) { + for len(subpackets) > 0 { + subpackets, err = parseSignatureSubpacket(sig, subpackets, isHashed) + if err != nil { + return + } + } + + if sig.CreationTime.IsZero() { + err = errors.StructuralError("no creation time in signature") + } + + return +} + +type signatureSubpacketType uint8 + +const ( + creationTimeSubpacket signatureSubpacketType = 2 + signatureExpirationSubpacket signatureSubpacketType = 3 + keyExpirationSubpacket signatureSubpacketType = 9 + prefSymmetricAlgosSubpacket signatureSubpacketType = 11 + issuerSubpacket signatureSubpacketType = 16 + prefHashAlgosSubpacket signatureSubpacketType = 21 + prefCompressionSubpacket signatureSubpacketType = 22 + primaryUserIdSubpacket signatureSubpacketType = 25 + keyFlagsSubpacket signatureSubpacketType = 27 + reasonForRevocationSubpacket signatureSubpacketType = 29 + featuresSubpacket signatureSubpacketType = 30 + embeddedSignatureSubpacket signatureSubpacketType = 32 +) + +// parseSignatureSubpacket parses a single subpacket. len(subpacket) is >= 1. +func parseSignatureSubpacket(sig *Signature, subpacket []byte, isHashed bool) (rest []byte, err 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 = errors.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 = errors.StructuralError("signature creation time in non-hashed area") + return + } + if len(subpacket) != 4 { + err = errors.StructuralError("signature creation time not four bytes") + return + } + t := binary.BigEndian.Uint32(subpacket) + sig.CreationTime = time.Unix(int64(t), 0) + case signatureExpirationSubpacket: + // Signature expiration time, section 5.2.3.10 + if !isHashed { + return + } + if len(subpacket) != 4 { + err = errors.StructuralError("expiration subpacket with bad length") + return + } + sig.SigLifetimeSecs = new(uint32) + *sig.SigLifetimeSecs = binary.BigEndian.Uint32(subpacket) + case keyExpirationSubpacket: + // Key expiration time, section 5.2.3.6 + if !isHashed { + return + } + if len(subpacket) != 4 { + err = errors.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 = errors.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 = errors.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 = errors.StructuralError("empty key flags subpacket") + return + } + sig.FlagsValid = true + if subpacket[0]&KeyFlagCertify != 0 { + sig.FlagCertify = true + } + if subpacket[0]&KeyFlagSign != 0 { + sig.FlagSign = true + } + if subpacket[0]&KeyFlagEncryptCommunications != 0 { + sig.FlagEncryptCommunications = true + } + if subpacket[0]&KeyFlagEncryptStorage != 0 { + sig.FlagEncryptStorage = true + } + case reasonForRevocationSubpacket: + // Reason For Revocation, section 5.2.3.23 + if !isHashed { + return + } + if len(subpacket) == 0 { + err = errors.StructuralError("empty revocation reason subpacket") + return + } + sig.RevocationReason = new(uint8) + *sig.RevocationReason = subpacket[0] + sig.RevocationReasonText = string(subpacket[1:]) + case featuresSubpacket: + // Features subpacket, section 5.2.3.24 specifies a very general + // mechanism for OpenPGP implementations to signal support for new + // features. In practice, the subpacket is used exclusively to + // indicate support for MDC-protected encryption. + sig.MDC = len(subpacket) >= 1 && subpacket[0]&1 == 1 + case embeddedSignatureSubpacket: + // Only usage is in signatures that cross-certify + // signing subkeys. section 5.2.3.26 describes the + // format, with its usage described in section 11.1 + if sig.EmbeddedSignature != nil { + err = errors.StructuralError("Cannot have multiple embedded signatures") + return + } + sig.EmbeddedSignature = new(Signature) + // Embedded signatures are required to be v4 signatures see + // section 12.1. However, we only parse v4 signatures in this + // file anyway. + if err := sig.EmbeddedSignature.parse(bytes.NewBuffer(subpacket)); err != nil { + return nil, err + } + if sigType := sig.EmbeddedSignature.SigType; sigType != SigTypePrimaryKeyBinding { + return nil, errors.StructuralError("cross-signature has unexpected type " + strconv.Itoa(int(sigType))) + } + default: + if isCritical { + err = errors.UnsupportedError("unknown critical signature subpacket type " + strconv.Itoa(int(packetType))) + return + } + } + return + +Truncated: + err = errors.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 { + // RFC 4880, Section 4.2.2. + if length < 192 { + to[0] = byte(length) + return 1 + } + if length < 16320 { + length -= 192 + to[0] = byte((length >> 8) + 192) + 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 +} + +// KeyExpired returns whether sig is a self-signature of a key that has +// expired. +func (sig *Signature) KeyExpired(currentTime time.Time) bool { + if sig.KeyLifetimeSecs == nil { + return false + } + expiry := sig.CreationTime.Add(time.Duration(*sig.KeyLifetimeSecs) * time.Second) + return currentTime.After(expiry) +} + +// buildHashSuffix constructs the HashSuffix member of sig in preparation for signing. +func (sig *Signature) buildHashSuffix() (err 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 errors.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 error) { + err = sig.buildHashSuffix() + if err != nil { + return + } + + h.Write(sig.HashSuffix) + digest = h.Sum(nil) + 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. +// If config is nil, sensible defaults will be used. +func (sig *Signature) Sign(h hash.Hash, priv *PrivateKey, config *Config) (err error) { + sig.outSubpackets = sig.buildSubpackets() + digest, err := sig.signPrepareHash(h) + if err != nil { + return + } + + switch priv.PubKeyAlgo { + case PubKeyAlgoRSA, PubKeyAlgoRSASignOnly: + // supports both *rsa.PrivateKey and crypto.Signer + sig.RSASignature.bytes, err = priv.PrivateKey.(crypto.Signer).Sign(config.Random(), digest, sig.Hash) + sig.RSASignature.bitLength = uint16(8 * len(sig.RSASignature.bytes)) + case PubKeyAlgoDSA: + dsaPriv := priv.PrivateKey.(*dsa.PrivateKey) + + // Need to truncate hashBytes to match FIPS 186-3 section 4.6. + subgroupSize := (dsaPriv.Q.BitLen() + 7) / 8 + if len(digest) > subgroupSize { + digest = digest[:subgroupSize] + } + r, s, err := dsa.Sign(config.Random(), dsaPriv, 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)) + } + case PubKeyAlgoECDSA: + var r, s *big.Int + if pk, ok := priv.PrivateKey.(*ecdsa.PrivateKey); ok { + // direct support, avoid asn1 wrapping/unwrapping + r, s, err = ecdsa.Sign(config.Random(), pk, digest) + } else { + var b []byte + b, err = priv.PrivateKey.(crypto.Signer).Sign(config.Random(), digest, nil) + if err == nil { + r, s, err = unwrapECDSASig(b) + } + } + if err == nil { + sig.ECDSASigR = fromBig(r) + sig.ECDSASigS = fromBig(s) + } + default: + err = errors.UnsupportedError("public key algorithm: " + strconv.Itoa(int(sig.PubKeyAlgo))) + } + + return +} + +// unwrapECDSASig parses the two integer components of an ASN.1-encoded ECDSA +// signature. +func unwrapECDSASig(b []byte) (r, s *big.Int, err error) { + var ecsdaSig struct { + R, S *big.Int + } + _, err = asn1.Unmarshal(b, &ecsdaSig) + if err != nil { + return + } + return ecsdaSig.R, ecsdaSig.S, nil +} + +// 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. +// If config is nil, sensible defaults will be used. +func (sig *Signature) SignUserId(id string, pub *PublicKey, priv *PrivateKey, config *Config) error { + h, err := userIdSignatureHash(id, pub, sig.Hash) + if err != nil { + return err + } + return sig.Sign(h, priv, config) +} + +// 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. +// If config is nil, sensible defaults will be used. +func (sig *Signature) SignKey(pub *PublicKey, priv *PrivateKey, config *Config) error { + h, err := keySignatureHash(&priv.PublicKey, pub, sig.Hash) + if err != nil { + return err + } + return sig.Sign(h, priv, config) +} + +// Serialize marshals sig to w. Sign, SignUserId or SignKey must have been +// called first. +func (sig *Signature) Serialize(w io.Writer) (err error) { + if len(sig.outSubpackets) == 0 { + sig.outSubpackets = sig.rawSubpackets + } + if sig.RSASignature.bytes == nil && sig.DSASigR.bytes == nil && sig.ECDSASigR.bytes == nil { + return errors.InvalidArgumentError("Signature: need to call Sign, SignUserId or SignKey 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) + case PubKeyAlgoECDSA: + sigLength = 2 + len(sig.ECDSASigR.bytes) + sigLength += 2 + len(sig.ECDSASigS.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) + case PubKeyAlgoECDSA: + err = writeMPIs(w, sig.ECDSASigR, sig.ECDSASigS) + 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) + binary.BigEndian.PutUint32(creationTime, uint32(sig.CreationTime.Unix())) + 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}) + } + + if sig.SigLifetimeSecs != nil && *sig.SigLifetimeSecs != 0 { + sigLifetime := make([]byte, 4) + binary.BigEndian.PutUint32(sigLifetime, *sig.SigLifetimeSecs) + subpackets = append(subpackets, outputSubpacket{true, signatureExpirationSubpacket, true, sigLifetime}) + } + + // Key flags may only appear in self-signatures or certification signatures. + + if sig.FlagsValid { + var flags byte + if sig.FlagCertify { + flags |= KeyFlagCertify + } + if sig.FlagSign { + flags |= KeyFlagSign + } + if sig.FlagEncryptCommunications { + flags |= KeyFlagEncryptCommunications + } + if sig.FlagEncryptStorage { + flags |= KeyFlagEncryptStorage + } + subpackets = append(subpackets, outputSubpacket{true, keyFlagsSubpacket, false, []byte{flags}}) + } + + // The following subpackets may only appear in self-signatures + + if sig.KeyLifetimeSecs != nil && *sig.KeyLifetimeSecs != 0 { + keyLifetime := make([]byte, 4) + binary.BigEndian.PutUint32(keyLifetime, *sig.KeyLifetimeSecs) + subpackets = append(subpackets, outputSubpacket{true, keyExpirationSubpacket, true, keyLifetime}) + } + + if sig.IsPrimaryId != nil && *sig.IsPrimaryId { + subpackets = append(subpackets, outputSubpacket{true, primaryUserIdSubpacket, false, []byte{1}}) + } + + if len(sig.PreferredSymmetric) > 0 { + subpackets = append(subpackets, outputSubpacket{true, prefSymmetricAlgosSubpacket, false, sig.PreferredSymmetric}) + } + + if len(sig.PreferredHash) > 0 { + subpackets = append(subpackets, outputSubpacket{true, prefHashAlgosSubpacket, false, sig.PreferredHash}) + } + + if len(sig.PreferredCompression) > 0 { + subpackets = append(subpackets, outputSubpacket{true, prefCompressionSubpacket, false, sig.PreferredCompression}) + } + + return +} diff --git a/vendor/golang.org/x/crypto/openpgp/packet/signature_v3.go b/vendor/golang.org/x/crypto/openpgp/packet/signature_v3.go new file mode 100644 index 00000000..6edff889 --- /dev/null +++ b/vendor/golang.org/x/crypto/openpgp/packet/signature_v3.go @@ -0,0 +1,146 @@ +// Copyright 2013 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" + "encoding/binary" + "fmt" + "io" + "strconv" + "time" + + "golang.org/x/crypto/openpgp/errors" + "golang.org/x/crypto/openpgp/s2k" +) + +// SignatureV3 represents older version 3 signatures. These signatures are less secure +// than version 4 and should not be used to create new signatures. They are included +// here for backwards compatibility to read and validate with older key material. +// See RFC 4880, section 5.2.2. +type SignatureV3 struct { + SigType SignatureType + CreationTime time.Time + IssuerKeyId uint64 + PubKeyAlgo PublicKeyAlgorithm + Hash crypto.Hash + HashTag [2]byte + + RSASignature parsedMPI + DSASigR, DSASigS parsedMPI +} + +func (sig *SignatureV3) parse(r io.Reader) (err error) { + // RFC 4880, section 5.2.2 + var buf [8]byte + if _, err = readFull(r, buf[:1]); err != nil { + return + } + if buf[0] < 2 || buf[0] > 3 { + err = errors.UnsupportedError("signature packet version " + strconv.Itoa(int(buf[0]))) + return + } + if _, err = readFull(r, buf[:1]); err != nil { + return + } + if buf[0] != 5 { + err = errors.UnsupportedError( + "invalid hashed material length " + strconv.Itoa(int(buf[0]))) + return + } + + // Read hashed material: signature type + creation time + if _, err = readFull(r, buf[:5]); err != nil { + return + } + sig.SigType = SignatureType(buf[0]) + t := binary.BigEndian.Uint32(buf[1:5]) + sig.CreationTime = time.Unix(int64(t), 0) + + // Eight-octet Key ID of signer. + if _, err = readFull(r, buf[:8]); err != nil { + return + } + sig.IssuerKeyId = binary.BigEndian.Uint64(buf[:]) + + // Public-key and hash algorithm + if _, err = readFull(r, buf[:2]); err != nil { + return + } + sig.PubKeyAlgo = PublicKeyAlgorithm(buf[0]) + switch sig.PubKeyAlgo { + case PubKeyAlgoRSA, PubKeyAlgoRSASignOnly, PubKeyAlgoDSA: + default: + err = errors.UnsupportedError("public key algorithm " + strconv.Itoa(int(sig.PubKeyAlgo))) + return + } + var ok bool + if sig.Hash, ok = s2k.HashIdToHash(buf[1]); !ok { + return errors.UnsupportedError("hash function " + strconv.Itoa(int(buf[2]))) + } + + // Two-octet field holding left 16 bits of signed hash value. + if _, err = readFull(r, sig.HashTag[:2]); err != nil { + return + } + + switch sig.PubKeyAlgo { + case PubKeyAlgoRSA, PubKeyAlgoRSASignOnly: + sig.RSASignature.bytes, sig.RSASignature.bitLength, err = readMPI(r) + case PubKeyAlgoDSA: + if sig.DSASigR.bytes, sig.DSASigR.bitLength, err = readMPI(r); err != nil { + return + } + sig.DSASigS.bytes, sig.DSASigS.bitLength, err = readMPI(r) + default: + panic("unreachable") + } + return +} + +// Serialize marshals sig to w. Sign, SignUserId or SignKey must have been +// called first. +func (sig *SignatureV3) Serialize(w io.Writer) (err error) { + buf := make([]byte, 8) + + // Write the sig type and creation time + buf[0] = byte(sig.SigType) + binary.BigEndian.PutUint32(buf[1:5], uint32(sig.CreationTime.Unix())) + if _, err = w.Write(buf[:5]); err != nil { + return + } + + // Write the issuer long key ID + binary.BigEndian.PutUint64(buf[:8], sig.IssuerKeyId) + if _, err = w.Write(buf[:8]); err != nil { + return + } + + // Write public key algorithm, hash ID, and hash value + buf[0] = byte(sig.PubKeyAlgo) + hashId, ok := s2k.HashToHashId(sig.Hash) + if !ok { + return errors.UnsupportedError(fmt.Sprintf("hash function %v", sig.Hash)) + } + buf[1] = hashId + copy(buf[2:4], sig.HashTag[:]) + if _, err = w.Write(buf[:4]); err != nil { + return + } + + if sig.RSASignature.bytes == nil && sig.DSASigR.bytes == nil { + return errors.InvalidArgumentError("Signature: need to call Sign, SignUserId or SignKey before Serialize") + } + + switch sig.PubKeyAlgo { + case PubKeyAlgoRSA, PubKeyAlgoRSASignOnly: + err = writeMPIs(w, sig.RSASignature) + case PubKeyAlgoDSA: + err = writeMPIs(w, sig.DSASigR, sig.DSASigS) + default: + panic("impossible") + } + return +} diff --git a/vendor/golang.org/x/crypto/openpgp/packet/symmetric_key_encrypted.go b/vendor/golang.org/x/crypto/openpgp/packet/symmetric_key_encrypted.go new file mode 100644 index 00000000..744c2d2c --- /dev/null +++ b/vendor/golang.org/x/crypto/openpgp/packet/symmetric_key_encrypted.go @@ -0,0 +1,155 @@ +// 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" + "io" + "strconv" + + "golang.org/x/crypto/openpgp/errors" + "golang.org/x/crypto/openpgp/s2k" +) + +// 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 + s2k func(out, in []byte) + encryptedKey []byte +} + +const symmetricKeyEncryptedVersion = 4 + +func (ske *SymmetricKeyEncrypted) parse(r io.Reader) error { + // RFC 4880, section 5.3. + var buf [2]byte + if _, err := readFull(r, buf[:]); err != nil { + return err + } + if buf[0] != symmetricKeyEncryptedVersion { + return errors.UnsupportedError("SymmetricKeyEncrypted version") + } + ske.CipherFunc = CipherFunction(buf[1]) + + if ske.CipherFunc.KeySize() == 0 { + return errors.UnsupportedError("unknown cipher: " + strconv.Itoa(int(buf[1]))) + } + + var err error + ske.s2k, err = s2k.Parse(r) + if err != nil { + return err + } + + 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 + } + + if n != 0 { + if n == maxSessionKeySizeInBytes { + return errors.UnsupportedError("oversized encrypted session key") + } + ske.encryptedKey = encryptedKey[:n] + } + + return nil +} + +// Decrypt attempts to decrypt an encrypted session key and returns the key and +// the cipher to use when decrypting a subsequent Symmetrically Encrypted Data +// packet. +func (ske *SymmetricKeyEncrypted) Decrypt(passphrase []byte) ([]byte, CipherFunction, error) { + key := make([]byte, ske.CipherFunc.KeySize()) + ske.s2k(key, passphrase) + + if len(ske.encryptedKey) == 0 { + return key, ske.CipherFunc, nil + } + + // the IV is all zeros + iv := make([]byte, ske.CipherFunc.blockSize()) + c := cipher.NewCFBDecrypter(ske.CipherFunc.new(key), iv) + plaintextKey := make([]byte, len(ske.encryptedKey)) + c.XORKeyStream(plaintextKey, ske.encryptedKey) + cipherFunc := CipherFunction(plaintextKey[0]) + if cipherFunc.blockSize() == 0 { + return nil, ske.CipherFunc, errors.UnsupportedError("unknown cipher: " + strconv.Itoa(int(cipherFunc))) + } + plaintextKey = plaintextKey[1:] + if l, cipherKeySize := len(plaintextKey), cipherFunc.KeySize(); l != cipherFunc.KeySize() { + return nil, cipherFunc, errors.StructuralError("length of decrypted key (" + strconv.Itoa(l) + ") " + + "not equal to cipher keysize (" + strconv.Itoa(cipherKeySize) + ")") + } + return plaintextKey, cipherFunc, 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. +// If config is nil, sensible defaults will be used. +func SerializeSymmetricKeyEncrypted(w io.Writer, passphrase []byte, config *Config) (key []byte, err error) { + cipherFunc := config.Cipher() + keySize := cipherFunc.KeySize() + if keySize == 0 { + return nil, errors.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, config.Random(), passphrase, &s2k.Config{Hash: config.Hash(), S2KCount: config.PasswordHashIterations()}) + 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(config.Random(), 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/vendor/golang.org/x/crypto/openpgp/packet/symmetrically_encrypted.go b/vendor/golang.org/x/crypto/openpgp/packet/symmetrically_encrypted.go new file mode 100644 index 00000000..6126030e --- /dev/null +++ b/vendor/golang.org/x/crypto/openpgp/packet/symmetrically_encrypted.go @@ -0,0 +1,290 @@ +// 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/sha1" + "crypto/subtle" + "golang.org/x/crypto/openpgp/errors" + "hash" + "io" + "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) 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 errors.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, error) { + keySize := c.KeySize() + if keySize == 0 { + return nil, errors.UnsupportedError("unknown cipher: " + strconv.Itoa(int(c))) + } + if len(key) != keySize { + return nil, errors.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, errors.InvalidArgumentError("can't try ciphers with different block lengths") + } + + ocfbResync := OCFBResync + if se.MDC { + // MDC packets use a different form of OCFB mode. + ocfbResync = OCFBNoResync + } + + s := NewOCFBDecrypter(c.new(key), se.prefix, ocfbResync) + if s == nil { + return nil, errors.ErrKeyIncorrect + } + + 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, error) { + return ser.in.Read(buf) +} + +func (ser seReader) Close() 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 error) { + if ser.error { + err = io.ErrUnexpectedEOF + return + } + if ser.eof { + err = io.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 == io.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 = io.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 == io.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() error { + if ser.error { + return errors.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 == io.EOF { + break + } + if err != nil { + return errors.SignatureError("error during reading") + } + } + + if ser.trailer[0] != mdcPacketTagByte || ser.trailer[1] != sha1.Size { + return errors.SignatureError("MDC packet not found") + } + ser.h.Write(ser.trailer[:2]) + + final := ser.h.Sum(nil) + if subtle.ConstantTimeCompare(final, ser.trailer[2:]) != 1 { + return errors.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 error) { + w.h.Write(buf) + return w.w.Write(buf) +} + +func (w *seMDCWriter) Close() (err error) { + var buf [mdcTrailerSize]byte + + buf[0] = mdcPacketTagByte + buf[1] = sha1.Size + w.h.Write(buf[:2]) + digest := w.h.Sum(nil) + 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 error) { + return c.w.Write(data) +} + +func (c noOpCloser) Close() 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. +// If config is nil, sensible defaults will be used. +func SerializeSymmetricallyEncrypted(w io.Writer, c CipherFunction, key []byte, config *Config) (contents io.WriteCloser, err error) { + if c.KeySize() != len(key) { + return nil, errors.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 = config.Random().Read(iv) + if err != nil { + return + } + s, prefix := NewOCFBEncrypter(block, iv, 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/vendor/golang.org/x/crypto/openpgp/packet/userattribute.go b/vendor/golang.org/x/crypto/openpgp/packet/userattribute.go new file mode 100644 index 00000000..96a2b382 --- /dev/null +++ b/vendor/golang.org/x/crypto/openpgp/packet/userattribute.go @@ -0,0 +1,91 @@ +// Copyright 2013 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" + "image" + "image/jpeg" + "io" + "io/ioutil" +) + +const UserAttrImageSubpacket = 1 + +// UserAttribute is capable of storing other types of data about a user +// beyond name, email and a text comment. In practice, user attributes are typically used +// to store a signed thumbnail photo JPEG image of the user. +// See RFC 4880, section 5.12. +type UserAttribute struct { + Contents []*OpaqueSubpacket +} + +// NewUserAttributePhoto creates a user attribute packet +// containing the given images. +func NewUserAttributePhoto(photos ...image.Image) (uat *UserAttribute, err error) { + uat = new(UserAttribute) + for _, photo := range photos { + var buf bytes.Buffer + // RFC 4880, Section 5.12.1. + data := []byte{ + 0x10, 0x00, // Little-endian image header length (16 bytes) + 0x01, // Image header version 1 + 0x01, // JPEG + 0, 0, 0, 0, // 12 reserved octets, must be all zero. + 0, 0, 0, 0, + 0, 0, 0, 0} + if _, err = buf.Write(data); err != nil { + return + } + if err = jpeg.Encode(&buf, photo, nil); err != nil { + return + } + uat.Contents = append(uat.Contents, &OpaqueSubpacket{ + SubType: UserAttrImageSubpacket, + Contents: buf.Bytes()}) + } + return +} + +// NewUserAttribute creates a new user attribute packet containing the given subpackets. +func NewUserAttribute(contents ...*OpaqueSubpacket) *UserAttribute { + return &UserAttribute{Contents: contents} +} + +func (uat *UserAttribute) parse(r io.Reader) (err error) { + // RFC 4880, section 5.13 + b, err := ioutil.ReadAll(r) + if err != nil { + return + } + uat.Contents, err = OpaqueSubpackets(b) + return +} + +// Serialize marshals the user attribute to w in the form of an OpenPGP packet, including +// header. +func (uat *UserAttribute) Serialize(w io.Writer) (err error) { + var buf bytes.Buffer + for _, sp := range uat.Contents { + sp.Serialize(&buf) + } + if err = serializeHeader(w, packetTypeUserAttribute, buf.Len()); err != nil { + return err + } + _, err = w.Write(buf.Bytes()) + return +} + +// ImageData returns zero or more byte slices, each containing +// JPEG File Interchange Format (JFIF), for each photo in the +// the user attribute packet. +func (uat *UserAttribute) ImageData() (imageData [][]byte) { + for _, sp := range uat.Contents { + if sp.SubType == UserAttrImageSubpacket && len(sp.Contents) > 16 { + imageData = append(imageData, sp.Contents[16:]) + } + } + return +} diff --git a/vendor/golang.org/x/crypto/openpgp/packet/userid.go b/vendor/golang.org/x/crypto/openpgp/packet/userid.go new file mode 100644 index 00000000..d6bea7d4 --- /dev/null +++ b/vendor/golang.org/x/crypto/openpgp/packet/userid.go @@ -0,0 +1,160 @@ +// 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" + "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 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) 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/vendor/golang.org/x/crypto/openpgp/read.go b/vendor/golang.org/x/crypto/openpgp/read.go new file mode 100644 index 00000000..6ec664f4 --- /dev/null +++ b/vendor/golang.org/x/crypto/openpgp/read.go @@ -0,0 +1,442 @@ +// 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 "golang.org/x/crypto/openpgp" + +import ( + "crypto" + _ "crypto/sha256" + "hash" + "io" + "strconv" + + "golang.org/x/crypto/openpgp/armor" + "golang.org/x/crypto/openpgp/errors" + "golang.org/x/crypto/openpgp/packet" +) + +// 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 error) { + block, err := armor.Decode(r) + if err != nil { + return + } + + if block.Type != expectedType { + return nil, errors.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 be 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 error // nil if the signature is good. + Signature *packet.Signature // the signature packet itself, if v4 (default) + SignatureV3 *packet.SignatureV3 // the signature packet if it is a v2 or v3 signature + + 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, 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. +// If config is nil, sensible defaults will be used. +func ReadMessage(r io.Reader, keyring KeyRing, prompt PromptFunction, config *packet.Config) (md *MessageDetails, err 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, errors.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, config) + } + if len(pk.encryptedKey.Key) == 0 { + continue + } + decrypted, err = se.Decrypt(pk.encryptedKey.CipherFunc, pk.encryptedKey.Key) + if err != nil && err != errors.ErrKeyIncorrect { + 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, errors.ErrKeyIncorrect + } + + if prompt == nil { + return nil, errors.ErrKeyIncorrect + } + + 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 { + key, cipherFunc, err := s.Decrypt(passphrase) + if err == nil { + decrypted, err = se.Decrypt(cipherFunc, key) + if err != nil && err != errors.ErrKeyIncorrect { + return nil, err + } + if decrypted != nil { + break FindKey + } + } + + } + } + } + + md.decrypted = decrypted + if err := packets.Push(decrypted); err != nil { + return nil, err + } + 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 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: + if err := packets.Push(p.Body); err != nil { + return nil, err + } + case *packet.OnePassSignature: + if !p.IsLast { + return nil, errors.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.KeysByIdUsage(p.KeyId, packet.KeyFlagSign) + if len(keys) > 0 { + md.SignedBy = &keys[0] + } + 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, error) { + if !hashId.Available() { + return nil, nil, errors.UnsupportedError("hash not available: " + strconv.Itoa(int(hashId))) + } + h := hashId.New() + + switch sigType { + case packet.SigTypeBinary: + return h, h, nil + case packet.SigTypeText: + return h, NewCanonicalTextHash(h), nil + } + + return nil, nil, errors.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 error) { + n, err = cr.md.LiteralData.Body.Read(buf) + if err == io.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 error) { + n, err = scr.md.LiteralData.Body.Read(buf) + scr.wrappedHash.Write(buf[:n]) + if err == io.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 = scr.md.SignedBy.PublicKey.VerifySignature(scr.h, scr.md.Signature) + } else if scr.md.SignatureV3, ok = p.(*packet.SignatureV3); ok { + scr.md.SignatureError = scr.md.SignedBy.PublicKey.VerifySignatureV3(scr.h, scr.md.SignatureV3) + } else { + scr.md.SignatureError = errors.StructuralError("LiteralData not followed by Signature") + return + } + + // 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 known, +// ErrUnknownIssuer is returned. +func CheckDetachedSignature(keyring KeyRing, signed, signature io.Reader) (signer *Entity, err error) { + var issuerKeyId uint64 + var hashFunc crypto.Hash + var sigType packet.SignatureType + var keys []Key + var p packet.Packet + + packets := packet.NewReader(signature) + for { + p, err = packets.Next() + if err == io.EOF { + return nil, errors.ErrUnknownIssuer + } + if err != nil { + return nil, err + } + + switch sig := p.(type) { + case *packet.Signature: + if sig.IssuerKeyId == nil { + return nil, errors.StructuralError("signature doesn't have an issuer") + } + issuerKeyId = *sig.IssuerKeyId + hashFunc = sig.Hash + sigType = sig.SigType + case *packet.SignatureV3: + issuerKeyId = sig.IssuerKeyId + hashFunc = sig.Hash + sigType = sig.SigType + default: + return nil, errors.StructuralError("non signature packet found") + } + + keys = keyring.KeysByIdUsage(issuerKeyId, packet.KeyFlagSign) + if len(keys) > 0 { + break + } + } + + if len(keys) == 0 { + panic("unreachable") + } + + h, wrappedHash, err := hashForSignature(hashFunc, sigType) + if err != nil { + return nil, err + } + + if _, err := io.Copy(wrappedHash, signed); err != nil && err != io.EOF { + return nil, err + } + + for _, key := range keys { + switch sig := p.(type) { + case *packet.Signature: + err = key.PublicKey.VerifySignature(h, sig) + case *packet.SignatureV3: + err = key.PublicKey.VerifySignatureV3(h, sig) + default: + panic("unreachable") + } + + if err == nil { + return key.Entity, nil + } + } + + return nil, err +} + +// 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 error) { + body, err := readArmored(signature, SignatureType) + if err != nil { + return + } + + return CheckDetachedSignature(keyring, signed, body) +} diff --git a/vendor/golang.org/x/crypto/openpgp/s2k/s2k.go b/vendor/golang.org/x/crypto/openpgp/s2k/s2k.go new file mode 100644 index 00000000..4b9a44ca --- /dev/null +++ b/vendor/golang.org/x/crypto/openpgp/s2k/s2k.go @@ -0,0 +1,273 @@ +// 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 "golang.org/x/crypto/openpgp/s2k" + +import ( + "crypto" + "hash" + "io" + "strconv" + + "golang.org/x/crypto/openpgp/errors" +) + +// Config collects configuration parameters for s2k key-stretching +// transformatioms. A nil *Config is valid and results in all default +// values. Currently, Config is used only by the Serialize function in +// this package. +type Config struct { + // Hash is the default hash function to be used. If + // nil, SHA1 is used. + Hash crypto.Hash + // S2KCount is only used for symmetric encryption. It + // determines the strength of the passphrase stretching when + // the said passphrase is hashed to produce a key. S2KCount + // should be between 1024 and 65011712, inclusive. If Config + // is nil or S2KCount is 0, the value 65536 used. Not all + // values in the above range can be represented. S2KCount will + // be rounded up to the next representable value if it cannot + // be encoded exactly. When set, it is strongly encrouraged to + // use a value that is at least 65536. See RFC 4880 Section + // 3.7.1.3. + S2KCount int +} + +func (c *Config) hash() crypto.Hash { + if c == nil || uint(c.Hash) == 0 { + // SHA1 is the historical default in this package. + return crypto.SHA1 + } + + return c.Hash +} + +func (c *Config) encodedCount() uint8 { + if c == nil || c.S2KCount == 0 { + return 96 // The common case. Correspoding to 65536 + } + + i := c.S2KCount + switch { + // Behave like GPG. Should we make 65536 the lowest value used? + case i < 1024: + i = 1024 + case i > 65011712: + i = 65011712 + } + + return encodeCount(i) +} + +// encodeCount converts an iterative "count" in the range 1024 to +// 65011712, inclusive, to an encoded count. The return value is the +// octet that is actually stored in the GPG file. encodeCount panics +// if i is not in the above range (encodedCount above takes care to +// pass i in the correct range). See RFC 4880 Section 3.7.7.1. +func encodeCount(i int) uint8 { + if i < 1024 || i > 65011712 { + panic("count arg i outside the required range") + } + + for encoded := 0; encoded < 256; encoded++ { + count := decodeCount(uint8(encoded)) + if count >= i { + return uint8(encoded) + } + } + + return 255 +} + +// decodeCount returns the s2k mode 3 iterative "count" corresponding to +// the encoded octet c. +func decodeCount(c uint8) int { + return (16 + int(c&15)) << (uint32(c>>4) + 6) +} + +// 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 + var digest []byte + + for i := 0; done < len(out); i++ { + h.Reset() + for j := 0; j < i; j++ { + h.Write(zero[:]) + } + h.Write(salt) + h.Write(in) + digest = h.Sum(digest[:0]) + n := copy(out[done:], digest) + 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 + var digest []byte + 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) + } + } + digest = h.Sum(digest[:0]) + n := copy(out[done:], digest) + 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 error) { + var buf [9]byte + + _, err = io.ReadFull(r, buf[:2]) + if err != nil { + return + } + + hash, ok := HashIdToHash(buf[1]) + if !ok { + return nil, errors.UnsupportedError("hash for S2K function: " + strconv.Itoa(int(buf[1]))) + } + if !hash.Available() { + return nil, errors.UnsupportedError("hash not available: " + strconv.Itoa(int(hash))) + } + h := hash.New() + + switch buf[0] { + case 0: + f := func(out, in []byte) { + Simple(out, h, in) + } + return f, nil + case 1: + _, 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 := decodeCount(buf[8]) + f := func(out, in []byte) { + Iterated(out, h, in, buf[:8], count) + } + return f, nil + } + + return nil, errors.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. The key stretching can be configured with c, which may be +// nil. In that case, sensible defaults will be used. +func Serialize(w io.Writer, key []byte, rand io.Reader, passphrase []byte, c *Config) error { + var buf [11]byte + buf[0] = 3 /* iterated and salted */ + buf[1], _ = HashToHashId(c.hash()) + salt := buf[2:10] + if _, err := io.ReadFull(rand, salt); err != nil { + return err + } + encodedCount := c.encodedCount() + count := decodeCount(encodedCount) + buf[10] = encodedCount + if _, err := w.Write(buf[:]); err != nil { + return err + } + + Iterated(key, c.hash().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 + name string +}{ + {1, crypto.MD5, "MD5"}, + {2, crypto.SHA1, "SHA1"}, + {3, crypto.RIPEMD160, "RIPEMD160"}, + {8, crypto.SHA256, "SHA256"}, + {9, crypto.SHA384, "SHA384"}, + {10, crypto.SHA512, "SHA512"}, + {11, crypto.SHA224, "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 +} + +// HashIdToString returns the name of the hash function corresponding to the +// given OpenPGP hash id. +func HashIdToString(id byte) (name string, ok bool) { + for _, m := range hashToHashIdMapping { + if m.id == id { + return m.name, true + } + } + + return "", 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/vendor/golang.org/x/crypto/openpgp/write.go b/vendor/golang.org/x/crypto/openpgp/write.go new file mode 100644 index 00000000..65a304cc --- /dev/null +++ b/vendor/golang.org/x/crypto/openpgp/write.go @@ -0,0 +1,378 @@ +// 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" + "hash" + "io" + "strconv" + "time" + + "golang.org/x/crypto/openpgp/armor" + "golang.org/x/crypto/openpgp/errors" + "golang.org/x/crypto/openpgp/packet" + "golang.org/x/crypto/openpgp/s2k" +) + +// DetachSign signs message with the private key from signer (which must +// already have been decrypted) and writes the signature to w. +// If config is nil, sensible defaults will be used. +func DetachSign(w io.Writer, signer *Entity, message io.Reader, config *packet.Config) error { + return detachSign(w, signer, message, packet.SigTypeBinary, config) +} + +// ArmoredDetachSign signs message with the private key from signer (which +// must already have been decrypted) and writes an armored signature to w. +// If config is nil, sensible defaults will be used. +func ArmoredDetachSign(w io.Writer, signer *Entity, message io.Reader, config *packet.Config) (err error) { + return armoredDetachSign(w, signer, message, packet.SigTypeBinary, config) +} + +// 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. +// If config is nil, sensible defaults will be used. +func DetachSignText(w io.Writer, signer *Entity, message io.Reader, config *packet.Config) error { + return detachSign(w, signer, message, packet.SigTypeText, config) +} + +// 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. +// If config is nil, sensible defaults will be used. +func ArmoredDetachSignText(w io.Writer, signer *Entity, message io.Reader, config *packet.Config) error { + return armoredDetachSign(w, signer, message, packet.SigTypeText, config) +} + +func armoredDetachSign(w io.Writer, signer *Entity, message io.Reader, sigType packet.SignatureType, config *packet.Config) (err error) { + out, err := armor.Encode(w, SignatureType, nil) + if err != nil { + return + } + err = detachSign(out, signer, message, sigType, config) + if err != nil { + return + } + return out.Close() +} + +func detachSign(w io.Writer, signer *Entity, message io.Reader, sigType packet.SignatureType, config *packet.Config) (err error) { + if signer.PrivateKey == nil { + return errors.InvalidArgumentError("signing key doesn't have a private key") + } + if signer.PrivateKey.Encrypted { + return errors.InvalidArgumentError("signing key is encrypted") + } + + sig := new(packet.Signature) + sig.SigType = sigType + sig.PubKeyAlgo = signer.PrivateKey.PubKeyAlgo + sig.Hash = config.Hash() + sig.CreationTime = config.Now() + 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, config) + 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 + // ModTime contains the modification time of the file, or the zero time if not applicable. + ModTime time.Time +} + +// 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. +// If config is nil, sensible defaults will be used. +func SymmetricallyEncrypt(ciphertext io.Writer, passphrase []byte, hints *FileHints, config *packet.Config) (plaintext io.WriteCloser, err error) { + if hints == nil { + hints = &FileHints{} + } + + key, err := packet.SerializeSymmetricKeyEncrypted(ciphertext, passphrase, config) + if err != nil { + return + } + w, err := packet.SerializeSymmetricallyEncrypted(ciphertext, config.Cipher(), key, config) + if err != nil { + return + } + + literaldata := w + if algo := config.Compression(); algo != packet.CompressionNone { + var compConfig *packet.CompressionConfig + if config != nil { + compConfig = config.CompressionConfig + } + literaldata, err = packet.SerializeCompressed(w, algo, compConfig) + if err != nil { + return + } + } + + var epochSeconds uint32 + if !hints.ModTime.IsZero() { + epochSeconds = uint32(hints.ModTime.Unix()) + } + return packet.SerializeLiteral(literaldata, hints.IsBinary, hints.FileName, 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. +// If config is nil, sensible defaults will be used. +func Encrypt(ciphertext io.Writer, to []*Entity, signed *Entity, hints *FileHints, config *packet.Config) (plaintext io.WriteCloser, err error) { + var signer *packet.PrivateKey + if signed != nil { + signKey, ok := signed.signingKey(config.Now()) + if !ok { + return nil, errors.InvalidArgumentError("no valid signing keys") + } + signer = signKey.PrivateKey + if signer == nil { + return nil, errors.InvalidArgumentError("no private key in signing key") + } + if signer.Encrypted { + return nil, errors.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 { + var ok bool + encryptKeys[i], ok = to[i].encryptionKey(config.Now()) + if !ok { + return nil, errors.InvalidArgumentError("cannot encrypt a message to key id " + strconv.FormatUint(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, errors.InvalidArgumentError("cannot encrypt because recipient set shares no common algorithms") + } + + cipher := packet.CipherFunction(candidateCiphers[0]) + // If the cipher specified by config is a candidate, we'll use that. + configuredCipher := config.Cipher() + for _, c := range candidateCiphers { + cipherFunc := packet.CipherFunction(c) + if cipherFunc == configuredCipher { + cipher = cipherFunc + break + } + } + + var hash crypto.Hash + for _, hashId := range candidateHashes { + if h, ok := s2k.HashIdToHash(hashId); ok && h.Available() { + hash = h + break + } + } + + // If the hash specified by config is a candidate, we'll use that. + if configuredHash := config.Hash(); configuredHash.Available() { + for _, hashId := range candidateHashes { + if h, ok := s2k.HashIdToHash(hashId); ok && h == configuredHash { + hash = h + break + } + } + } + + if hash == 0 { + hashId := candidateHashes[0] + name, ok := s2k.HashIdToString(hashId) + if !ok { + name = "#" + strconv.Itoa(int(hashId)) + } + return nil, errors.InvalidArgumentError("cannot encrypt because no candidate hash functions are compiled in. (Wanted " + name + " in this case.)") + } + + symKey := make([]byte, cipher.KeySize()) + if _, err := io.ReadFull(config.Random(), symKey); err != nil { + return nil, err + } + + for _, key := range encryptKeys { + if err := packet.SerializeEncryptedKey(ciphertext, key.PublicKey, cipher, symKey, config); err != nil { + return nil, err + } + } + + encryptedData, err := packet.SerializeSymmetricallyEncrypted(ciphertext, cipher, symKey, config) + 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} + + } + var epochSeconds uint32 + if !hints.ModTime.IsZero() { + epochSeconds = uint32(hints.ModTime.Unix()) + } + literalData, err := packet.SerializeLiteral(w, hints.IsBinary, hints.FileName, epochSeconds) + if err != nil { + return nil, err + } + + if signer != nil { + return signatureWriter{encryptedData, literalData, hash, hash.New(), signer, config}, 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 + config *packet.Config +} + +func (s signatureWriter) Write(data []byte) (int, error) { + s.h.Write(data) + return s.literalData.Write(data) +} + +func (s signatureWriter) Close() error { + sig := &packet.Signature{ + SigType: packet.SigTypeBinary, + PubKeyAlgo: s.signer.PubKeyAlgo, + Hash: s.hashType, + CreationTime: s.config.Now(), + IssuerKeyId: &s.signer.KeyId, + } + + if err := sig.Sign(s.h, s.signer, s.config); 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 error) { + return c.w.Write(data) +} + +func (c noOpCloser) Close() error { + return nil +} |