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