190, 229, 108, 82, 89, 166, 116, 210, 230, 244, 180,
192, 209, 102, 175, 194, 57, 75, 99, 182,
}
- piInv [256]byte
- cBlk [32]*[BlockSize]byte
+ piInv [256]byte
+ cBlk [32][]byte
+ gfCache [256][256]byte
)
func gf(a, b byte) (c byte) {
return
}
-func l(blk *[BlockSize]byte, rounds int) {
- var t byte
- var i int
- for ; rounds > 0; rounds-- {
- t = blk[15]
- for i = 14; i >= 0; i-- {
- blk[i+1] = blk[i]
- t ^= gf(blk[i], lc[i])
- }
+func l(blk []byte) {
+ for n := 0; n < BlockSize; n++ {
+ t := blk[15]
+ t ^= gfCache[blk[0]][lc[0]]
+ t ^= gfCache[blk[1]][lc[1]]
+ t ^= gfCache[blk[2]][lc[2]]
+ t ^= gfCache[blk[3]][lc[3]]
+ t ^= gfCache[blk[4]][lc[4]]
+ t ^= gfCache[blk[5]][lc[5]]
+ t ^= gfCache[blk[6]][lc[6]]
+ t ^= gfCache[blk[7]][lc[7]]
+ t ^= gfCache[blk[8]][lc[8]]
+ t ^= gfCache[blk[9]][lc[9]]
+ t ^= gfCache[blk[10]][lc[10]]
+ t ^= gfCache[blk[11]][lc[11]]
+ t ^= gfCache[blk[12]][lc[12]]
+ t ^= gfCache[blk[13]][lc[13]]
+ t ^= gfCache[blk[14]][lc[14]]
+ copy(blk[1:], blk)
blk[0] = t
}
}
-func lInv(blk *[BlockSize]byte) {
- var t byte
- var i int
+func lInv(blk []byte) {
for n := 0; n < BlockSize; n++ {
- t = blk[0]
- for i = 0; i < 15; i++ {
- blk[i] = blk[i+1]
- t ^= gf(blk[i], lc[i])
- }
+ t := blk[0]
+ copy(blk, blk[1:])
+ t ^= gfCache[blk[0]][lc[0]]
+ t ^= gfCache[blk[1]][lc[1]]
+ t ^= gfCache[blk[2]][lc[2]]
+ t ^= gfCache[blk[3]][lc[3]]
+ t ^= gfCache[blk[4]][lc[4]]
+ t ^= gfCache[blk[5]][lc[5]]
+ t ^= gfCache[blk[6]][lc[6]]
+ t ^= gfCache[blk[7]][lc[7]]
+ t ^= gfCache[blk[8]][lc[8]]
+ t ^= gfCache[blk[9]][lc[9]]
+ t ^= gfCache[blk[10]][lc[10]]
+ t ^= gfCache[blk[11]][lc[11]]
+ t ^= gfCache[blk[12]][lc[12]]
+ t ^= gfCache[blk[13]][lc[13]]
+ t ^= gfCache[blk[14]][lc[14]]
blk[15] = t
}
}
func init() {
- piInvP := new([256]byte)
+ for a := 0; a < 256; a++ {
+ for b := 0; b < 256; b++ {
+ gfCache[a][b] = gf(byte(a), byte(b))
+ }
+ }
for i := 0; i < 256; i++ {
- piInvP[int(pi[i])] = byte(i)
+ piInv[int(pi[i])] = byte(i)
}
- piInv = *piInvP
- CP := new([32]*[BlockSize]byte)
for i := 0; i < 32; i++ {
- CP[i] = new([BlockSize]byte)
- CP[i][15] = byte(i) + 1
- l(CP[i], 16)
+ cBlk[i] = make([]byte, BlockSize)
+ cBlk[i][15] = byte(i) + 1
+ l(cBlk[i])
}
- cBlk = *CP
}
-func s(blk *[BlockSize]byte) {
- for i := 0; i < BlockSize; i++ {
- blk[i] = pi[int(blk[i])]
- }
+func s(blk []byte) {
+ blk[0] = pi[int(blk[0])]
+ blk[1] = pi[int(blk[1])]
+ blk[2] = pi[int(blk[2])]
+ blk[3] = pi[int(blk[3])]
+ blk[4] = pi[int(blk[4])]
+ blk[5] = pi[int(blk[5])]
+ blk[6] = pi[int(blk[6])]
+ blk[7] = pi[int(blk[7])]
+ blk[8] = pi[int(blk[8])]
+ blk[9] = pi[int(blk[9])]
+ blk[10] = pi[int(blk[10])]
+ blk[11] = pi[int(blk[11])]
+ blk[12] = pi[int(blk[12])]
+ blk[13] = pi[int(blk[13])]
+ blk[14] = pi[int(blk[14])]
+ blk[15] = pi[int(blk[15])]
}
-func xor(dst, src1, src2 *[BlockSize]byte) {
- for i := 0; i < BlockSize; i++ {
- dst[i] = src1[i] ^ src2[i]
- }
+func xor(dst, src1, src2 []byte) {
+ dst[0] = src1[0] ^ src2[0]
+ dst[1] = src1[1] ^ src2[1]
+ dst[2] = src1[2] ^ src2[2]
+ dst[3] = src1[3] ^ src2[3]
+ dst[4] = src1[4] ^ src2[4]
+ dst[5] = src1[5] ^ src2[5]
+ dst[6] = src1[6] ^ src2[6]
+ dst[7] = src1[7] ^ src2[7]
+ dst[8] = src1[8] ^ src2[8]
+ dst[9] = src1[9] ^ src2[9]
+ dst[10] = src1[10] ^ src2[10]
+ dst[11] = src1[11] ^ src2[11]
+ dst[12] = src1[12] ^ src2[12]
+ dst[13] = src1[13] ^ src2[13]
+ dst[14] = src1[14] ^ src2[14]
+ dst[15] = src1[15] ^ src2[15]
}
type Cipher struct {
- ks [10]*[BlockSize]byte
+ ks [10][]byte
}
func (c *Cipher) BlockSize() int {
if len(key) != KeySize {
panic("invalid key size")
}
- ks := new([10]*[BlockSize]byte)
- kr0 := new([BlockSize]byte)
- kr1 := new([BlockSize]byte)
- krt := new([BlockSize]byte)
- copy(kr0[:], key[:BlockSize])
- copy(kr1[:], key[BlockSize:])
- ks[0] = new([BlockSize]byte)
- ks[1] = new([BlockSize]byte)
- copy(ks[0][:], kr0[:])
- copy(ks[1][:], kr1[:])
+ var ks [10][]byte
+ for i := 0; i < len(ks); i++ {
+ ks[i] = make([]byte, BlockSize)
+ }
+ kr0 := make([]byte, BlockSize)
+ kr1 := make([]byte, BlockSize)
+ krt := make([]byte, BlockSize)
+ copy(kr0, key[:BlockSize])
+ copy(kr1, key[BlockSize:])
+ copy(ks[0], kr0)
+ copy(ks[1], kr1)
for i := 0; i < 4; i++ {
for j := 0; j < 8; j++ {
xor(krt, kr0, cBlk[8*i+j])
s(krt)
- l(krt, 16)
+ l(krt)
xor(krt, krt, kr1)
- copy(kr1[:], kr0[:])
- copy(kr0[:], krt[:])
+ copy(kr1, kr0)
+ copy(kr0, krt)
}
- ks[2+2*i] = new([BlockSize]byte)
- copy(ks[2+2*i][:], kr0[:])
- ks[2+2*i+1] = new([BlockSize]byte)
- copy(ks[2+2*i+1][:], kr1[:])
+ copy(ks[2+2*i], kr0)
+ copy(ks[2+2*i+1], kr1)
}
- return &Cipher{*ks}
+ return &Cipher{ks}
}
func (c *Cipher) Encrypt(dst, src []byte) {
- blk := new([BlockSize]byte)
- copy(blk[:], src)
+ blk := make([]byte, BlockSize)
+ copy(blk, src)
for i := 0; i < 9; i++ {
xor(blk, blk, c.ks[i])
s(blk)
- l(blk, 16)
+ l(blk)
}
xor(blk, blk, c.ks[9])
- copy(dst[:BlockSize], blk[:])
+ copy(dst[:BlockSize], blk)
}
func (c *Cipher) Decrypt(dst, src []byte) {
- blk := new([BlockSize]byte)
- copy(blk[:], src)
+ blk := make([]byte, BlockSize)
+ copy(blk, src)
var n int
for i := 9; i > 0; i-- {
xor(blk, blk, c.ks[i])
}
}
xor(blk, blk, c.ks[0])
- copy(dst[:BlockSize], blk[:])
+ copy(dst[:BlockSize], blk)
}