hash writers: adler32, crc32, md5, sha1.
all could probably be made faster.
R=r
DELTA=929 (929 added, 0 deleted, 0 changed)
OCL=19879
CL=19911
diff --git a/src/lib/hash/sha1block.go b/src/lib/hash/sha1block.go
new file mode 100644
index 0000000..a81dceb
--- /dev/null
+++ b/src/lib/hash/sha1block.go
@@ -0,0 +1,86 @@
+// 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.
+
+// SHA1 block step.
+// In its own file so that a faster assembly or C version
+// can be substituted easily.
+
+package sha1
+
+import "sha1"
+
+const (
+ K0 = 0x5A827999;
+ K1 = 0x6ED9EBA1;
+ K2 = 0x8F1BBCDC;
+ K3 = 0xCA62C1D6;
+)
+
+package func Block(dig *Digest, p *[]byte) int {
+ var w [80]uint32;
+
+ n := 0;
+ h0, h1, h2, h3, h4 := dig.h[0], dig.h[1], dig.h[2], dig.h[3], dig.h[4];
+ for len(p) >= Chunk {
+ // Can interlace the computation of w with the
+ // rounds below if needed for speed.
+ for i := 0; i < 16; i++ {
+ j := i*4;
+ w[i] = uint32(p[j])<<24 |
+ uint32(p[j+1])<<16 |
+ uint32(p[j+2])<<8 |
+ uint32(p[j+3]);
+ }
+ for i := 16; i < 80; i++ {
+ tmp := w[i-3] ^ w[i-8] ^ w[i-14] ^ w[i-16];
+ w[i] = tmp<<1 | tmp>>(32-1);
+ }
+
+ a, b, c, d, e := h0, h1, h2, h3, h4;
+
+ // Each of the four 20-iteration rounds
+ // differs only in the computation of f and
+ // the choice of K (K0, K1, etc).
+ for i := 0; i < 20; i++ {
+ f := b&c | (^b)&d;
+ a5 := a<<5 | a>>(32-5);
+ b30 := b<<30 | b>>(32-30);
+ t := a5 + f + e + w[i] + K0;
+ a, b, c, d, e = t, a, b30, c, d;
+ }
+ for i := 20; i < 40; i++ {
+ f := b ^ c ^ d;
+ a5 := a<<5 | a>>(32-5);
+ b30 := b<<30 | b>>(32-30);
+ t := a5 + f + e + w[i] + K1;
+ a, b, c, d, e = t, a, b30, c, d;
+ }
+ for i := 40; i < 60; i++ {
+ f := b&c | b&d | c&d;
+ a5 := a<<5 | a>>(32-5);
+ b30 := b<<30 | b>>(32-30);
+ t := a5 + f + e + w[i] + K2;
+ a, b, c, d, e = t, a, b30, c, d;
+ }
+ for i := 60; i < 80; i++ {
+ f := b ^ c ^ d;
+ a5 := a<<5 | a>>(32-5);
+ b30 := b<<30 | b>>(32-30);
+ t := a5 + f + e + w[i] + K3;
+ a, b, c, d, e = t, a, b30, c, d;
+ }
+
+ h0 += a;
+ h1 += b;
+ h2 += c;
+ h3 += d;
+ h4 += e;
+
+ p = p[Chunk:len(p)];
+ n += Chunk;
+ }
+
+ dig.h[0], dig.h[1], dig.h[2], dig.h[3], dig.h[4] = h0, h1, h2, h3, h4;
+ return n;
+}
