go.crypto/sha3: update to sync with draft FIPS-202
1. API:
This exposes a minimal API: the SHA-3 functions implement hash.Hash. The
SHAKE functions implement a new "ShakeHash" interface that implements
io.Reader, io.Writer, and Reset().
(The previous Barrier() function has been removed.)
(Alternative proposal: Don't implement io.Reader, but instead provide a
"Digest(d []byte) error" function that performs a hash.Hash style copy.
Somewhat more minimal, but very easy to use incorrectly.)
2. Tests
Added the complete set of ShortMsgKATs from
https://github.com/gvanas/KeccakCodePackage
3. Correctness
In sync with draft FIPS-202.
4. Documentation
A summary of the security properties of the SHA-3 and SHAKE functions is
provided in doc.go; some concrete recommendations as well.
Fixes 8563.
R=golang-codereviews, agl
CC=golang-codereviews
https://golang.org/cl/130950043
diff --git a/sha3/keccakf.go b/sha3/keccakf.go
index 76c0312..c267ee0 100644
--- a/sha3/keccakf.go
+++ b/sha3/keccakf.go
@@ -1,16 +1,11 @@
-// Copyright 2013 The Go Authors. All rights reserved.
+// Copyright 2014 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 sha3
-// This file implements the core Keccak permutation function necessary for computing SHA3.
-// This is implemented in a separate file to allow for replacement by an optimized implementation.
-// Nothing in this package is exported.
-// For the detailed specification, refer to the Keccak web site (http://keccak.noekeon.org/).
-
// rc stores the round constants for use in the ι step.
-var rc = [...]uint64{
+var rc = [24]uint64{
0x0000000000000001,
0x0000000000008082,
0x800000000000808A,
@@ -37,10 +32,9 @@
0x8000000080008008,
}
-// keccakF computes the complete Keccak-f function consisting of 24 rounds with a different
-// constant (rc) in each round. This implementation fully unrolls the round function to avoid
-// inner loops, as well as pre-calculating shift offsets.
-func keccakF(a *[numLanes]uint64) {
+// keccakF1600 applies the Keccak permutation to a 1600b-wide
+// state represented as a slice of 25 uint64s.
+func keccakF1600(a *[25]uint64) {
var t, bc0, bc1, bc2, bc3, bc4 uint64
for _, roundConstant := range rc {
// θ step
