mirror of https://github.com/minio/minio.git
170 lines
3.1 KiB
Go
170 lines
3.1 KiB
Go
// 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 of
|
|
// Golang project:
|
|
// https://github.com/golang/go/blob/master/LICENSE
|
|
|
|
// Using this part of Minio codebase under the license
|
|
// Apache License Version 2.0 with modifications
|
|
|
|
// Package sha1 implements the SHA1 hash algorithm as defined in RFC 3174.
|
|
package sha1
|
|
|
|
import (
|
|
"hash"
|
|
"io"
|
|
|
|
"github.com/minio/minio/pkg/utils/cpu"
|
|
)
|
|
|
|
// The size of a SHA1 checksum in bytes.
|
|
const Size = 20
|
|
|
|
// The blocksize of SHA1 in bytes.
|
|
const BlockSize = 64
|
|
|
|
const (
|
|
chunk = 64
|
|
init0 = 0x67452301
|
|
init1 = 0xEFCDAB89
|
|
init2 = 0x98BADCFE
|
|
init3 = 0x10325476
|
|
init4 = 0xC3D2E1F0
|
|
)
|
|
|
|
// digest represents the partial evaluation of a checksum.
|
|
type digest struct {
|
|
h [5]uint32
|
|
x [chunk]byte
|
|
nx int
|
|
len uint64
|
|
}
|
|
|
|
// Reset digest
|
|
func (d *digest) Reset() {
|
|
d.h[0] = init0
|
|
d.h[1] = init1
|
|
d.h[2] = init2
|
|
d.h[3] = init3
|
|
d.h[4] = init4
|
|
d.nx = 0
|
|
d.len = 0
|
|
}
|
|
|
|
// New returns a new hash.Hash computing the SHA1 checksum.
|
|
func New() hash.Hash {
|
|
d := new(digest)
|
|
d.Reset()
|
|
return d
|
|
}
|
|
|
|
func block(dig *digest, p []byte) {
|
|
switch true {
|
|
case cpu.HasAVX2() == true:
|
|
blockAVX2(dig, p)
|
|
case cpu.HasSSE41() == true:
|
|
blockSSE3(dig, p)
|
|
default:
|
|
blockGeneric(dig, p)
|
|
}
|
|
}
|
|
|
|
// Return output size
|
|
func (d *digest) Size() int { return Size }
|
|
|
|
// Return checksum blocksize
|
|
func (d *digest) BlockSize() int { return BlockSize }
|
|
|
|
// Write to digest
|
|
func (d *digest) Write(p []byte) (nn int, err error) {
|
|
nn = len(p)
|
|
d.len += uint64(nn)
|
|
if d.nx > 0 {
|
|
n := copy(d.x[d.nx:], p)
|
|
d.nx += n
|
|
if d.nx == chunk {
|
|
block(d, d.x[:])
|
|
d.nx = 0
|
|
}
|
|
p = p[n:]
|
|
}
|
|
if len(p) >= chunk {
|
|
n := len(p) &^ (chunk - 1)
|
|
block(d, p[:n])
|
|
p = p[n:]
|
|
}
|
|
if len(p) > 0 {
|
|
d.nx = copy(d.x[:], p)
|
|
}
|
|
return
|
|
}
|
|
|
|
// Return checksum bytes
|
|
func (d *digest) Sum(in []byte) []byte {
|
|
// Make a copy of d0 so that caller can keep writing and summing.
|
|
d0 := *d
|
|
hash := d0.checkSum()
|
|
return append(in, hash[:]...)
|
|
}
|
|
|
|
// Intermediate checksum function
|
|
func (d *digest) checkSum() [Size]byte {
|
|
len := d.len
|
|
// Padding. Add a 1 bit and 0 bits until 56 bytes mod 64.
|
|
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 >> (56 - 8*i))
|
|
}
|
|
d.Write(tmp[0:8])
|
|
|
|
if d.nx != 0 {
|
|
panic("d.nx != 0")
|
|
}
|
|
|
|
var digest [Size]byte
|
|
for i, s := range d.h {
|
|
digest[i*4] = byte(s >> 24)
|
|
digest[i*4+1] = byte(s >> 16)
|
|
digest[i*4+2] = byte(s >> 8)
|
|
digest[i*4+3] = byte(s)
|
|
}
|
|
|
|
return digest
|
|
}
|
|
|
|
/// Convenience functions
|
|
|
|
// Sum1 - single caller sha1 helper
|
|
func Sum1(data []byte) [Size]byte {
|
|
var d digest
|
|
d.Reset()
|
|
d.Write(data)
|
|
return d.checkSum()
|
|
}
|
|
|
|
// Sum - io.Reader based streaming sha1 helper
|
|
func Sum(reader io.Reader) ([]byte, error) {
|
|
h := New()
|
|
var err error
|
|
for err == nil {
|
|
length := 0
|
|
byteBuffer := make([]byte, 1024*1024)
|
|
length, err = reader.Read(byteBuffer)
|
|
byteBuffer = byteBuffer[0:length]
|
|
h.Write(byteBuffer)
|
|
}
|
|
if err != io.EOF {
|
|
return nil, err
|
|
}
|
|
return h.Sum(nil), nil
|
|
}
|