crypto/sha*: replace putUint{32,64} helpers

Replaces putUint{32,64} functions in crypto/sha* packages with the
equivalent functions encoding/binary.BigEndian.PutUint{32,64}.

Change-Id: I9208d2125202ea9c97777560e6917d21893aced0
Reviewed-on: https://go-review.googlesource.com/c/go/+/156117
Reviewed-by: Brad Fitzpatrick <[email protected]>
Run-TryBot: Brad Fitzpatrick <[email protected]>
TryBot-Result: Gobot Gobot <[email protected]>

Author: mmcloughlin

src/crypto/sha1/sha1.go

@@ -10,6 +10,7 @@ package sha1
 
 import (
 	"crypto"
+	"encoding/binary"
 	"errors"
 	"hash"
 )
@@ -81,13 +82,13 @@ func (d *digest) UnmarshalBinary(b []byte) error {
 
 func appendUint64(b []byte, x uint64) []byte {
 	var a [8]byte
-	putUint64(a[:], x)
+	binary.BigEndian.PutUint64(a[:], x)
 	return append(b, a[:]...)
 }
 
 func appendUint32(b []byte, x uint32) []byte {
 	var a [4]byte
-	putUint32(a[:], x)
+	binary.BigEndian.PutUint32(a[:], x)
 	return append(b, a[:]...)
 }
 
@@ -170,7 +171,7 @@ func (d *digest) checkSum() [Size]byte {
 
 	// Length in bits.
 	len <<= 3
-	putUint64(tmp[:], len)
+	binary.BigEndian.PutUint64(tmp[:], len)
 	d.Write(tmp[0:8])
 
 	if d.nx != 0 {
@@ -179,11 +180,11 @@ func (d *digest) checkSum() [Size]byte {
 
 	var digest [Size]byte
 
-	putUint32(digest[0:], d.h[0])
-	putUint32(digest[4:], d.h[1])
-	putUint32(digest[8:], d.h[2])
-	putUint32(digest[12:], d.h[3])
-	putUint32(digest[16:], d.h[4])
+	binary.BigEndian.PutUint32(digest[0:], d.h[0])
+	binary.BigEndian.PutUint32(digest[4:], d.h[1])
+	binary.BigEndian.PutUint32(digest[8:], d.h[2])
+	binary.BigEndian.PutUint32(digest[12:], d.h[3])
+	binary.BigEndian.PutUint32(digest[16:], d.h[4])
 
 	return digest
 }
@@ -263,23 +264,3 @@ func Sum(data []byte) [Size]byte {
 	d.Write(data)
 	return d.checkSum()
 }
-
-func putUint64(x []byte, s uint64) {
-	_ = x[7]
-	x[0] = byte(s >> 56)
-	x[1] = byte(s >> 48)
-	x[2] = byte(s >> 40)
-	x[3] = byte(s >> 32)
-	x[4] = byte(s >> 24)
-	x[5] = byte(s >> 16)
-	x[6] = byte(s >> 8)
-	x[7] = byte(s)
-}
-
-func putUint32(x []byte, s uint32) {
-	_ = x[3]
-	x[0] = byte(s >> 24)
-	x[1] = byte(s >> 16)
-	x[2] = byte(s >> 8)
-	x[3] = byte(s)
-}

src/crypto/sha256/sha256.go

@@ -8,6 +8,7 @@ package sha256
 
 import (
 	"crypto"
+	"encoding/binary"
 	"errors"
 	"hash"
 )
@@ -104,35 +105,15 @@ func (d *digest) UnmarshalBinary(b []byte) error {
 	return nil
 }
 
-func putUint32(x []byte, s uint32) {
-	_ = x[3]
-	x[0] = byte(s >> 24)
-	x[1] = byte(s >> 16)
-	x[2] = byte(s >> 8)
-	x[3] = byte(s)
-}
-
-func putUint64(x []byte, s uint64) {
-	_ = x[7]
-	x[0] = byte(s >> 56)
-	x[1] = byte(s >> 48)
-	x[2] = byte(s >> 40)
-	x[3] = byte(s >> 32)
-	x[4] = byte(s >> 24)
-	x[5] = byte(s >> 16)
-	x[6] = byte(s >> 8)
-	x[7] = byte(s)
-}
-
 func appendUint64(b []byte, x uint64) []byte {
 	var a [8]byte
-	putUint64(a[:], x)
+	binary.BigEndian.PutUint64(a[:], x)
 	return append(b, a[:]...)
 }
 
 func appendUint32(b []byte, x uint32) []byte {
 	var a [4]byte
-	putUint32(a[:], x)
+	binary.BigEndian.PutUint32(a[:], x)
 	return append(b, a[:]...)
 }
 
@@ -246,7 +227,7 @@ func (d *digest) checkSum() [Size]byte {
 
 	// Length in bits.
 	len <<= 3
-	putUint64(tmp[:], len)
+	binary.BigEndian.PutUint64(tmp[:], len)
 	d.Write(tmp[0:8])
 
 	if d.nx != 0 {
@@ -255,15 +236,15 @@ func (d *digest) checkSum() [Size]byte {
 
 	var digest [Size]byte
 
-	putUint32(digest[0:], d.h[0])
-	putUint32(digest[4:], d.h[1])
-	putUint32(digest[8:], d.h[2])
-	putUint32(digest[12:], d.h[3])
-	putUint32(digest[16:], d.h[4])
-	putUint32(digest[20:], d.h[5])
-	putUint32(digest[24:], d.h[6])
+	binary.BigEndian.PutUint32(digest[0:], d.h[0])
+	binary.BigEndian.PutUint32(digest[4:], d.h[1])
+	binary.BigEndian.PutUint32(digest[8:], d.h[2])
+	binary.BigEndian.PutUint32(digest[12:], d.h[3])
+	binary.BigEndian.PutUint32(digest[16:], d.h[4])
+	binary.BigEndian.PutUint32(digest[20:], d.h[5])
+	binary.BigEndian.PutUint32(digest[24:], d.h[6])
 	if !d.is224 {
-		putUint32(digest[28:], d.h[7])
+		binary.BigEndian.PutUint32(digest[28:], d.h[7])
 	}
 
 	return digest

src/crypto/sha512/sha512.go

@@ -12,6 +12,7 @@ package sha512
 
 import (
 	"crypto"
+	"encoding/binary"
 	"errors"
 	"hash"
 )
@@ -195,21 +196,9 @@ func (d *digest) UnmarshalBinary(b []byte) error {
 	return nil
 }
 
-func putUint64(x []byte, s uint64) {
-	_ = x[7]
-	x[0] = byte(s >> 56)
-	x[1] = byte(s >> 48)
-	x[2] = byte(s >> 40)
-	x[3] = byte(s >> 32)
-	x[4] = byte(s >> 24)
-	x[5] = byte(s >> 16)
-	x[6] = byte(s >> 8)
-	x[7] = byte(s)
-}
-
 func appendUint64(b []byte, x uint64) []byte {
 	var a [8]byte
-	putUint64(a[:], x)
+	binary.BigEndian.PutUint64(a[:], x)
 	return append(b, a[:]...)
 }
 
@@ -316,24 +305,24 @@ func (d *digest) checkSum() [Size]byte {
 
 	// Length in bits.
 	len <<= 3
-	putUint64(tmp[0:], 0) // upper 64 bits are always zero, because len variable has type uint64
-	putUint64(tmp[8:], len)
+	binary.BigEndian.PutUint64(tmp[0:], 0) // upper 64 bits are always zero, because len variable has type uint64
+	binary.BigEndian.PutUint64(tmp[8:], len)
 	d.Write(tmp[0:16])
 
 	if d.nx != 0 {
 		panic("d.nx != 0")
 	}
 
 	var digest [Size]byte
-	putUint64(digest[0:], d.h[0])
-	putUint64(digest[8:], d.h[1])
-	putUint64(digest[16:], d.h[2])
-	putUint64(digest[24:], d.h[3])
-	putUint64(digest[32:], d.h[4])
-	putUint64(digest[40:], d.h[5])
+	binary.BigEndian.PutUint64(digest[0:], d.h[0])
+	binary.BigEndian.PutUint64(digest[8:], d.h[1])
+	binary.BigEndian.PutUint64(digest[16:], d.h[2])
+	binary.BigEndian.PutUint64(digest[24:], d.h[3])
+	binary.BigEndian.PutUint64(digest[32:], d.h[4])
+	binary.BigEndian.PutUint64(digest[40:], d.h[5])
 	if d.function != crypto.SHA384 {
-		putUint64(digest[48:], d.h[6])
-		putUint64(digest[56:], d.h[7])
+		binary.BigEndian.PutUint64(digest[48:], d.h[6])
+		binary.BigEndian.PutUint64(digest[56:], d.h[7])
 	}
 
 	return digest