Use Intel optimized code (ssse3, avx, avx2) to calculate sha256

pkg/utils/crypto/sha256/sha256.go

@@ -1,59 +1,162 @@
-// +build amd64
-
+// Package sha256 SHA256SSE3, SHA256AVX, SHA256AVX2
 package sha256
 
-// #include <stdint.h>
-// void sha256_transform_avx (uint8_t *input_data, uint32_t digest[8], uint64_t num_blks);
-// void sha256_transform_ssse3 (uint8_t *input_data, uint32_t digest[8], uint64_t num_blks);
-// void sha256_transform_rorx (uint8_t *input_data, uint32_t digest[8], uint64_t num_blks);
-// #define SHA256_DIGEST_SIZE      32
-// #define SHA256_BLOCK_SIZE       64
-// #define SHA256_H0       0x6a09e667UL
-// #define SHA256_H1       0xbb67ae85UL
-// #define SHA256_H2       0x3c6ef372UL
-// #define SHA256_H3       0xa54ff53aUL
-// #define SHA256_H4       0x510e527fUL
-// #define SHA256_H5       0x9b05688cUL
-// #define SHA256_H6       0x1f83d9abUL
-// #define SHA256_H7       0x5be0cd19UL
-import "C"
 import (
-	gosha256 "crypto/sha256"
+	"hash"
 	"io"
+
+	"github.com/minio-io/minio/pkg/utils/cpu"
 )
 
-/*
-func Sha256(buffer []byte) ([]uint32, error) {
+// The size of a SHA256 checksum in bytes.
+const Size = 32
 
-	if cpu.HasSSE41() {
-		C.sha256_transform_ssse3()
-		return 0, nil
-	}
+// The blocksize of SHA256 in bytes.
+const BlockSize = 64
 
-	if cpu.HasAVX() {
-		C.sha256_transform_avx()
-		return 0, nil
-	}
+const (
+	chunk = 64
+	init0 = 0x6A09E667
+	init1 = 0xBB67AE85
+	init2 = 0x3C6EF372
+	init3 = 0xA54FF53A
+	init4 = 0x510E527F
+	init5 = 0x9B05688C
+	init6 = 0x1F83D9AB
+	init7 = 0x5BE0CD19
+)
 
-	if cpu.HasAVX2() {
-		C.sha256_transform_rorx()
-		return 0, nil
+// digest represents the partial evaluation of a checksum.
+type digest struct {
+	h   [8]uint32
+	x   [chunk]byte
+	nx  int
+	len uint64
+}
+
+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.h[5] = init5
+	d.h[6] = init6
+	d.h[7] = init7
+	d.nx = 0
+	d.len = 0
+}
+
+func block(dig *digest, p []byte) {
+	switch true {
+	case cpu.HasAVX2() == true:
+		blockAVX2(dig, p)
+	case cpu.HasAVX() == true:
+		blockAVX(dig, p)
+	case cpu.HasSSE41() == true:
+		blockSSE(dig, p)
 	}
 }
-*/
+
+// New returns a new hash.Hash computing the SHA256 checksum.
+func New() hash.Hash {
+	d := new(digest)
+	d.Reset()
+	return d
+}
+
+func (d *digest) Size() int {
+	return Size
+}
+
+func (d *digest) BlockSize() int { return BlockSize }
+
+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
+}
+
+func (d0 *digest) Sum(in []byte) []byte {
+	// Make a copy of d0 so that caller can keep writing and summing.
+	d := *d0
+	hash := d.checkSum()
+	return append(in, hash[:]...)
+}
+
+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")
+	}
+
+	h := d.h[:]
+
+	var digest [Size]byte
+	for i, s := range 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
+
+func Sum256(data []byte) [Size]byte {
+	var d digest
+	d.Reset()
+	d.Write(data)
+	return d.checkSum()
+}
 
 func Sum(reader io.Reader) ([]byte, error) {
-	hash := gosha256.New()
+	h := New()
 	var err error
 	for err == nil {
 		length := 0
 		byteBuffer := make([]byte, 1024*1024)
 		length, err = reader.Read(byteBuffer)
 		byteBuffer = byteBuffer[0:length]
-		hash.Write(byteBuffer)
+		h.Write(byteBuffer)
 	}
 	if err != io.EOF {
 		return nil, err
 	}
-	return hash.Sum(nil), nil
+	return h.Sum(nil), nil
 }