diff options
| author | Ian Lance Taylor <iant@golang.org> | 2013-02-07 13:31:53 -0800 |
|---|---|---|
| committer | Ian Lance Taylor <iant@golang.org> | 2013-02-07 13:31:53 -0800 |
| commit | 2b44c33b4a9ca2fa25c88e85803daa57f1080a03 (patch) | |
| tree | 912539a890028651719516ec99ff3d87e90720e1 /src/pkg/crypto | |
| parent | 514f10b9ab59c3aa7689fad9c22557f7037e8c42 (diff) | |
| download | go-2b44c33b4a9ca2fa25c88e85803daa57f1080a03.tar.xz | |
crypto/md5: fix for big-endian processors
R=golang-dev, minux.ma, agl
CC=golang-dev
https://golang.org/cl/7305059
Diffstat (limited to 'src/pkg/crypto')
| -rw-r--r-- | src/pkg/crypto/md5/md5block.go | 14 |
1 files changed, 12 insertions, 2 deletions
diff --git a/src/pkg/crypto/md5/md5block.go b/src/pkg/crypto/md5/md5block.go index 59f8f6f5af..0ca4217740 100644 --- a/src/pkg/crypto/md5/md5block.go +++ b/src/pkg/crypto/md5/md5block.go @@ -5,6 +5,16 @@ import ( "unsafe" ) +const x86 = runtime.GOARCH == "amd64" || runtime.GOARCH == "386" + +var littleEndian bool + +func init() { + x := uint32(0x04030201) + y := [4]byte{0x1, 0x2, 0x3, 0x4} + littleEndian = *(*[4]byte)(unsafe.Pointer(&x)) == y +} + func block(dig *digest, p []byte) { a := dig.s[0] b := dig.s[1] @@ -16,13 +26,13 @@ func block(dig *digest, p []byte) { aa, bb, cc, dd := a, b, c, d // This is a constant condition - it is not evaluated on each iteration. - if runtime.GOARCH == "amd64" || runtime.GOARCH == "386" { + if x86 { // MD5 was designed so that x86 processors can just iterate // over the block data directly as uint32s, and we generate // less code and run 1.3x faster if we take advantage of that. // My apologies. X = (*[16]uint32)(unsafe.Pointer(&p[0])) - } else if uintptr(unsafe.Pointer(&p[0]))&(unsafe.Alignof(uint32(0))-1) == 0 { + } else if littleEndian && uintptr(unsafe.Pointer(&p[0]))&(unsafe.Alignof(uint32(0))-1) == 0 { X = (*[16]uint32)(unsafe.Pointer(&p[0])) } else { X = &xbuf |