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Diffstat (limited to 'libgo/go/crypto/openpgp/armor')
-rw-r--r--libgo/go/crypto/openpgp/armor/armor.go220
-rw-r--r--libgo/go/crypto/openpgp/armor/armor_test.go97
-rw-r--r--libgo/go/crypto/openpgp/armor/encode.go162
3 files changed, 479 insertions, 0 deletions
diff --git a/libgo/go/crypto/openpgp/armor/armor.go b/libgo/go/crypto/openpgp/armor/armor.go
new file mode 100644
index 000000000..97080f6c6
--- /dev/null
+++ b/libgo/go/crypto/openpgp/armor/armor.go
@@ -0,0 +1,220 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This package 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 (
+ "bytes"
+ "crypto/openpgp/error"
+ "encoding/base64"
+ "encoding/line"
+ "io"
+ "os"
+)
+
+// A Block represents an OpenPGP armored structure.
+//
+// The encoded form is:
+// -----BEGIN Type-----
+// Headers
+//
+// base64-encoded Bytes
+// '=' base64 encoded checksum
+// -----END Type-----
+// where Headers is a possibly empty sequence of Key: Value lines.
+//
+// Since the armored data can be very large, this package presents a streaming
+// interface.
+type Block struct {
+ Type string // The type, taken from the preamble (i.e. "PGP SIGNATURE").
+ Header map[string]string // Optional headers.
+ Body io.Reader // A Reader from which the contents can be read
+ lReader lineReader
+ oReader openpgpReader
+}
+
+var ArmorCorrupt os.Error = error.StructuralError("armor invalid")
+
+const crc24Init = 0xb704ce
+const crc24Poly = 0x1864cfb
+const crc24Mask = 0xffffff
+
+// crc24 calculates the OpenPGP checksum as specified in RFC 4880, section 6.1
+func crc24(crc uint32, d []byte) uint32 {
+ for _, b := range d {
+ crc ^= uint32(b) << 16
+ for i := 0; i < 8; i++ {
+ crc <<= 1
+ if crc&0x1000000 != 0 {
+ crc ^= crc24Poly
+ }
+ }
+ }
+ return crc
+}
+
+var armorStart = []byte("-----BEGIN ")
+var armorEnd = []byte("-----END ")
+var armorEndOfLine = []byte("-----")
+
+// lineReader wraps a line based reader. It watches for the end of an armor
+// block and records the expected CRC value.
+type lineReader struct {
+ in *line.Reader
+ buf []byte
+ eof bool
+ crc uint32
+}
+
+func (l *lineReader) Read(p []byte) (n int, err os.Error) {
+ if l.eof {
+ return 0, os.EOF
+ }
+
+ if len(l.buf) > 0 {
+ n = copy(p, l.buf)
+ l.buf = l.buf[n:]
+ return
+ }
+
+ line, isPrefix, err := l.in.ReadLine()
+ if err != nil {
+ return
+ }
+ if isPrefix {
+ return 0, ArmorCorrupt
+ }
+
+ if len(line) == 5 && line[0] == '=' {
+ // This is the checksum line
+ var expectedBytes [3]byte
+ var m int
+ m, err = base64.StdEncoding.Decode(expectedBytes[0:], line[1:])
+ if m != 3 || err != nil {
+ return
+ }
+ l.crc = uint32(expectedBytes[0])<<16 |
+ uint32(expectedBytes[1])<<8 |
+ uint32(expectedBytes[2])
+
+ line, _, err = l.in.ReadLine()
+ if err != nil && err != os.EOF {
+ return
+ }
+ if !bytes.HasPrefix(line, armorEnd) {
+ return 0, ArmorCorrupt
+ }
+
+ l.eof = true
+ return 0, os.EOF
+ }
+
+ if len(line) != 64 {
+ return 0, ArmorCorrupt
+ }
+
+ n = copy(p, line)
+ bytesToSave := len(line) - n
+ if bytesToSave > 0 {
+ if cap(l.buf) < bytesToSave {
+ l.buf = make([]byte, 0, bytesToSave)
+ }
+ l.buf = l.buf[0:bytesToSave]
+ copy(l.buf, line[n:])
+ }
+
+ return
+}
+
+// openpgpReader passes Read calls to the underlying base64 decoder, but keeps
+// a running CRC of the resulting data and checks the CRC against the value
+// found by the lineReader at EOF.
+type openpgpReader struct {
+ lReader *lineReader
+ b64Reader io.Reader
+ currentCRC uint32
+}
+
+func (r *openpgpReader) Read(p []byte) (n int, err os.Error) {
+ n, err = r.b64Reader.Read(p)
+ r.currentCRC = crc24(r.currentCRC, p[:n])
+
+ if err == os.EOF {
+ if r.lReader.crc != uint32(r.currentCRC&crc24Mask) {
+ return 0, ArmorCorrupt
+ }
+ }
+
+ return
+}
+
+// Decode reads a PGP armored block from the given Reader. It will ignore
+// leading garbage. If it doesn't find a block, it will return nil, os.EOF. The
+// given Reader is not usable after calling this function: an arbitary amount
+// of data may have been read past the end of the block.
+func Decode(in io.Reader) (p *Block, err os.Error) {
+ r := line.NewReader(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/libgo/go/crypto/openpgp/armor/armor_test.go b/libgo/go/crypto/openpgp/armor/armor_test.go
new file mode 100644
index 000000000..e4ffd414b
--- /dev/null
+++ b/libgo/go/crypto/openpgp/armor/armor_test.go
@@ -0,0 +1,97 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package armor
+
+import (
+ "bytes"
+ "hash/adler32"
+ "io/ioutil"
+ "testing"
+)
+
+func TestDecodeEncode(t *testing.T) {
+ buf := bytes.NewBuffer([]byte(armorExample1))
+ result, err := Decode(buf)
+ if err != nil {
+ t.Error(err)
+ }
+ expectedType := "PGP SIGNATURE"
+ if result.Type != expectedType {
+ t.Errorf("result.Type: got:%s want:%s", result.Type, expectedType)
+ }
+ if len(result.Header) != 1 {
+ t.Errorf("len(result.Header): got:%d want:1", len(result.Header))
+ }
+ v, ok := result.Header["Version"]
+ if !ok || v != "GnuPG v1.4.10 (GNU/Linux)" {
+ t.Errorf("result.Header: got:%#v", result.Header)
+ }
+
+ contents, err := ioutil.ReadAll(result.Body)
+ if err != nil {
+ t.Error(err)
+ }
+
+ if adler32.Checksum(contents) != 0x789d7f00 {
+ t.Errorf("contents: got: %x", contents)
+ }
+
+ buf = bytes.NewBuffer(nil)
+ w, err := Encode(buf, result.Type, result.Header)
+ if err != nil {
+ t.Error(err)
+ }
+ _, err = w.Write(contents)
+ if err != nil {
+ t.Error(err)
+ }
+ w.Close()
+
+ if !bytes.Equal(buf.Bytes(), []byte(armorExample1)) {
+ t.Errorf("got: %s\nwant: %s", string(buf.Bytes()), armorExample1)
+ }
+}
+
+func TestLongHeader(t *testing.T) {
+ buf := bytes.NewBuffer([]byte(armorLongLine))
+ result, err := Decode(buf)
+ if err != nil {
+ t.Error(err)
+ return
+ }
+ value, ok := result.Header["Version"]
+ if !ok {
+ t.Errorf("missing Version header")
+ }
+ if value != longValueExpected {
+ t.Errorf("got: %s want: %s", value, longValueExpected)
+ }
+}
+
+const armorExample1 = `-----BEGIN PGP SIGNATURE-----
+Version: GnuPG v1.4.10 (GNU/Linux)
+
+iQEcBAABAgAGBQJMtFESAAoJEKsQXJGvOPsVj40H/1WW6jaMXv4BW+1ueDSMDwM8
+kx1fLOXbVM5/Kn5LStZNt1jWWnpxdz7eq3uiqeCQjmqUoRde3YbB2EMnnwRbAhpp
+cacnAvy9ZQ78OTxUdNW1mhX5bS6q1MTEJnl+DcyigD70HG/yNNQD7sOPMdYQw0TA
+byQBwmLwmTsuZsrYqB68QyLHI+DUugn+kX6Hd2WDB62DKa2suoIUIHQQCd/ofwB3
+WfCYInXQKKOSxu2YOg2Eb4kLNhSMc1i9uKUWAH+sdgJh7NBgdoE4MaNtBFkHXRvv
+okWuf3+xA9ksp1npSY/mDvgHijmjvtpRDe6iUeqfCn8N9u9CBg8geANgaG8+QA4=
+=wfQG
+-----END PGP SIGNATURE-----`
+
+const armorLongLine = `-----BEGIN PGP SIGNATURE-----
+Version: 0123456789abcdefghijklmnopqrstuvwxyz0123456789abcdefghijklmnopqrstuvwxyz0123456789abcdefghijklmnopqrstuvwxyz0123456789abcdefghijklmnopqrstuvwxyz0123456789abcdefghijklmnopqrstuvwxyz0123456789abcdefghijklmnopqrstuvwxyz0123456789abcdefghijklmnopqrstuvwxyz0123456789abcdefghijklmnopqrstuvwxyz0123456789abcdefghijklmnopqrstuvwxyz
+
+iQEcBAABAgAGBQJMtFESAAoJEKsQXJGvOPsVj40H/1WW6jaMXv4BW+1ueDSMDwM8
+kx1fLOXbVM5/Kn5LStZNt1jWWnpxdz7eq3uiqeCQjmqUoRde3YbB2EMnnwRbAhpp
+cacnAvy9ZQ78OTxUdNW1mhX5bS6q1MTEJnl+DcyigD70HG/yNNQD7sOPMdYQw0TA
+byQBwmLwmTsuZsrYqB68QyLHI+DUugn+kX6Hd2WDB62DKa2suoIUIHQQCd/ofwB3
+WfCYInXQKKOSxu2YOg2Eb4kLNhSMc1i9uKUWAH+sdgJh7NBgdoE4MaNtBFkHXRvv
+okWuf3+xA9ksp1npSY/mDvgHijmjvtpRDe6iUeqfCn8N9u9CBg8geANgaG8+QA4=
+=wfQG
+-----END PGP SIGNATURE-----`
+
+const longValueExpected = "0123456789abcdefghijklmnopqrstuvwxyz0123456789abcdefghijklmnopqrstuvwxyz0123456789abcdefghijklmnopqrstuvwxyz0123456789abcdefghijklmnopqrstuvwxyz0123456789abcdefghijklmnopqrstuvwxyz0123456789abcdefghijklmnopqrstuvwxyz0123456789abcdefghijklmnopqrstuvwxyz0123456789abcdefghijklmnopqrstuvwxyz0123456789abcdefghijklmnopqrstuvwxyz"
diff --git a/libgo/go/crypto/openpgp/armor/encode.go b/libgo/go/crypto/openpgp/armor/encode.go
new file mode 100644
index 000000000..410e73460
--- /dev/null
+++ b/libgo/go/crypto/openpgp/armor/encode.go
@@ -0,0 +1,162 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package armor
+
+import (
+ "encoding/base64"
+ "io"
+ "os"
+)
+
+var armorHeaderSep = []byte(": ")
+var blockEnd = []byte("\n=")
+var newline = []byte("\n")
+var armorEndOfLineOut = []byte("-----\n")
+
+// writeSlices writes its arguments to the given Writer.
+func writeSlices(out io.Writer, slices ...[]byte) (err os.Error) {
+ for _, s := range slices {
+ _, err := out.Write(s)
+ if err != nil {
+ return
+ }
+ }
+ return
+}
+
+// lineBreaker breaks data across several lines, all of the same byte length
+// (except possibly the last). Lines are broken with a single '\n'.
+type lineBreaker struct {
+ lineLength int
+ line []byte
+ used int
+ out io.Writer
+ haveWritten bool
+}
+
+func newLineBreaker(out io.Writer, lineLength int) *lineBreaker {
+ return &lineBreaker{
+ lineLength: lineLength,
+ line: make([]byte, lineLength),
+ used: 0,
+ out: out,
+ }
+}
+
+func (l *lineBreaker) Write(b []byte) (n int, err os.Error) {
+ n = len(b)
+
+ if n == 0 {
+ return
+ }
+
+ if l.used == 0 && l.haveWritten {
+ _, err = l.out.Write([]byte{'\n'})
+ if err != nil {
+ return
+ }
+ }
+
+ if l.used+len(b) < l.lineLength {
+ l.used += copy(l.line[l.used:], b)
+ return
+ }
+
+ l.haveWritten = true
+ _, err = l.out.Write(l.line[0:l.used])
+ if err != nil {
+ return
+ }
+ excess := l.lineLength - l.used
+ l.used = 0
+
+ _, err = l.out.Write(b[0:excess])
+ if err != nil {
+ return
+ }
+
+ _, err = l.Write(b[excess:])
+ return
+}
+
+func (l *lineBreaker) Close() (err os.Error) {
+ if l.used > 0 {
+ _, err = l.out.Write(l.line[0:l.used])
+ if err != nil {
+ return
+ }
+ }
+
+ return
+}
+
+// encoding keeps track of a running CRC24 over the data which has been written
+// to it and outputs a OpenPGP checksum when closed, followed by an armor
+// trailer.
+//
+// It's built into a stack of io.Writers:
+// encoding -> base64 encoder -> lineBreaker -> out
+type encoding struct {
+ out io.Writer
+ breaker *lineBreaker
+ b64 io.WriteCloser
+ crc uint32
+ blockType []byte
+}
+
+func (e *encoding) Write(data []byte) (n int, err os.Error) {
+ e.crc = crc24(e.crc, data)
+ return e.b64.Write(data)
+}
+
+func (e *encoding) Close() (err os.Error) {
+ err = e.b64.Close()
+ if err != nil {
+ return
+ }
+
+ var checksumBytes [3]byte
+ checksumBytes[0] = byte(e.crc >> 16)
+ checksumBytes[1] = byte(e.crc >> 8)
+ checksumBytes[2] = byte(e.crc)
+
+ var b64ChecksumBytes [4]byte
+ base64.StdEncoding.Encode(b64ChecksumBytes[:], checksumBytes[:])
+
+ return writeSlices(e.out, blockEnd, b64ChecksumBytes[:], newline, armorEnd, e.blockType, armorEndOfLine)
+}
+
+// Encode returns a WriteCloser which will encode the data written to it in
+// OpenPGP armor.
+func Encode(out io.Writer, blockType string, headers map[string]string) (w io.WriteCloser, err os.Error) {
+ bType := []byte(blockType)
+ err = writeSlices(out, armorStart, bType, armorEndOfLineOut)
+ if err != nil {
+ return
+ }
+
+ for k, v := range headers {
+ err = writeSlices(out, []byte(k), armorHeaderSep, []byte(v), newline)
+ if err != nil {
+ return
+ }
+ }
+
+ if len(headers) > 0 {
+ _, 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
+}