1 files changed, 117 insertions, 0 deletions
diff --git a/src/pkg/crypto/md5/md5.go b/src/pkg/crypto/md5/md5.go
new file mode 100644
index 000000000..cbc007f01
--- /dev/null
+++ b/src/pkg/crypto/md5/md5.go
@@ -0,0 +1,117 @@
+// Copyright 2009 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 the MD5 hash algorithm as defined in RFC 1321.
+package md5
+
+import (
+	"hash";
+	"os";
+)
+
+// The size of an MD5 checksum in bytes.
+const Size = 16;
+
+const (
+	_Chunk = 64;
+
+	_Init0 = 0x67452301;
+	_Init1 = 0xEFCDAB89;
+	_Init2 = 0x98BADCFE;
+	_Init3 = 0x10325476;
+)
+
+// digest represents the partial evaluation of a checksum.
+type digest struct {
+	s [4]uint32;
+	x [_Chunk]byte;
+	nx int;
+	len uint64;
+}
+
+func (d *digest) Reset() {
+	d.s[0] = _Init0;
+	d.s[1] = _Init1;
+	d.s[2] = _Init2;
+	d.s[3] = _Init3;
+	d.nx = 0;
+	d.len = 0;
+}
+
+// New returns a Hash computing the SHA1 checksum.
+func New() hash.Hash {
+	d := new(digest);
+	d.Reset();
+	return d;
+}
+
+func (d *digest) Size() int {
+	return Size;
+}
+
+func _Block(dig *digest, p []byte) int
+
+func (d *digest) Write(p []byte) (nn int, err os.Error) {
+	nn = len(p);
+	d.len += uint64(nn);
+	if d.nx > 0 {
+		n := len(p);
+		if n > _Chunk-d.nx {
+			n = _Chunk-d.nx;
+		}
+		for i := 0; i < n; i++ {
+			d.x[d.nx+i] = p[i];
+		}
+		d.nx += n;
+		if d.nx == _Chunk {
+			_Block(d, &d.x);
+			d.nx = 0;
+		}
+		p = p[n:len(p)];
+	}
+	n := _Block(d, p);
+	p = p[n:len(p)];
+	if len(p) > 0 {
+		for i := 0; i < len(p); i++ {
+			d.x[i] = p[i];
+		}
+		d.nx = len(p);
+	}
+	return;
+}
+
+func (d *digest) Sum() []byte {
+	// Padding.  Add a 1 bit and 0 bits until 56 bytes mod 64.
+	len := d.len;
+	var tmp [64]byte;
+	tmp[0] = 0x80;
+	if len%64 < 56 {
+		d.Write(tmp[0:56-len%64]);
+	} else {
+		d.Write(tmp[0:64+56-len%64]);
+	}
+
+	// Length in bits.
+	len <<= 3;
+	for i := uint(0); i < 8; i++ {
+		tmp[i] = byte(len>>(8*i));
+	}
+	d.Write(tmp[0:8]);
+
+	if d.nx != 0 {
+		panicln("oops");
+	}
+
+	p := make([]byte, 16);
+	j := 0;
+	for i := 0; i < 4; i++ {
+		s := d.s[i];
+		p[j] = byte(s); j++;
+		p[j] = byte(s>>8); j++;
+		p[j] = byte(s>>16); j++;
+		p[j] = byte(s>>24); j++;
+	}
+	return p;
+}
+