diff options
Diffstat (limited to 'src/pkg/crypto/openpgp/canonical_text.go')
-rw-r--r-- | src/pkg/crypto/openpgp/canonical_text.go | 58 |
1 files changed, 58 insertions, 0 deletions
diff --git a/src/pkg/crypto/openpgp/canonical_text.go b/src/pkg/crypto/openpgp/canonical_text.go new file mode 100644 index 000000000..293eff354 --- /dev/null +++ b/src/pkg/crypto/openpgp/canonical_text.go @@ -0,0 +1,58 @@ +// Copyright 2011 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package openpgp + +import ( + "hash" + "os" +) + +// NewCanonicalTextHash reformats text written to it into the canonical +// form and then applies the hash h. See RFC 4880, section 5.2.1. +func NewCanonicalTextHash(h hash.Hash) hash.Hash { + return &canonicalTextHash{h, 0} +} + +type canonicalTextHash struct { + h hash.Hash + s int +} + +var newline = []byte{'\r', '\n'} + +func (cth *canonicalTextHash) Write(buf []byte) (int, os.Error) { + start := 0 + + for i, c := range buf { + switch cth.s { + case 0: + if c == '\r' { + cth.s = 1 + } else if c == '\n' { + cth.h.Write(buf[start:i]) + cth.h.Write(newline) + start = i + 1 + } + case 1: + cth.s = 0 + } + } + + cth.h.Write(buf[start:]) + return len(buf), nil +} + +func (cth *canonicalTextHash) Sum() []byte { + return cth.h.Sum() +} + +func (cth *canonicalTextHash) Reset() { + cth.h.Reset() + cth.s = 0 +} + +func (cth *canonicalTextHash) Size() int { + return cth.h.Size() +} |