; Copyright 2015 Egor Tensin ; This file is licensed under the terms of the MIT License. ; See LICENSE.txt for details. .586 .xmm .model flat .data align 10h key_schedule oword 13 dup(0) align 10h inverted_key_schedule oword 13 dup(0) .code @raw_aes192ecb_encrypt@48 proc call expand_keys192 pxor xmm0, [key_schedule] aesenc xmm0, [key_schedule + 10h] aesenc xmm0, [key_schedule + 20h] aesenc xmm0, [key_schedule + 30h] aesenc xmm0, [key_schedule + 40h] aesenc xmm0, [key_schedule + 50h] aesenc xmm0, [key_schedule + 60h] aesenc xmm0, [key_schedule + 70h] aesenc xmm0, [key_schedule + 80h] aesenc xmm0, [key_schedule + 90h] aesenc xmm0, [key_schedule + 0A0h] aesenc xmm0, [key_schedule + 0B0h] aesenclast xmm0, [key_schedule + 0C0h] ret @raw_aes192ecb_encrypt@48 endp @raw_aes192ecb_decrypt@48 proc call expand_keys192 pxor xmm0, [inverted_key_schedule] aesdec xmm0, [inverted_key_schedule + 10h] aesdec xmm0, [inverted_key_schedule + 20h] aesdec xmm0, [inverted_key_schedule + 30h] aesdec xmm0, [inverted_key_schedule + 40h] aesdec xmm0, [inverted_key_schedule + 50h] aesdec xmm0, [inverted_key_schedule + 60h] aesdec xmm0, [inverted_key_schedule + 70h] aesdec xmm0, [inverted_key_schedule + 80h] aesdec xmm0, [inverted_key_schedule + 90h] aesdec xmm0, [inverted_key_schedule + 0A0h] aesdec xmm0, [inverted_key_schedule + 0B0h] aesdeclast xmm0, [inverted_key_schedule + 0C0h] ret @raw_aes192ecb_decrypt@48 endp expand_keys192 proc ; A "word" (in terms of the FIPS 187 standard) is a 32-bit block. ; Words are denoted by `w[N]`. ; ; A key schedule is composed of 12 "regular" keys and a dumb key for ; the "whitening" step. ; It's stored in `key_schedule`. ; ; A key schedule is thus composed of 52 "words". ; The FIPS standard includes an algorithm to calculate these words via ; a simple loop: ; ; i = 6 ; while i < 52: ; temp = w[i - 1] ; if i % 6 == 0: ; temp = SubWord(RotWord(temp))^Rcon ; w[i] = w[i - 6]^temp ; i = i + 1 ; ; The loop above may be unrolled like this: ; ; w[6] = SubWord(RotWord(w[5]))^Rcon^w[0] ; w[7] = w[6]^w[1] ; = SubWord(RotWord(w[5]))^Rcon^w[0]^w[1] ; w[8] = w[7]^w[2] ; = SubWord(RotWord(w[5]))^Rcon^w[0]^w[1]^w[2] ; w[9] = w[8]^w[3] ; = SubWord(RotWord(w[5]))^Rcon^w[0]^w[1]^w[2]^w[3] ; w[10] = w[9]^w[4] ; = SubWord(RotWord(w[5]))^Rcon^w[0]^w[1]^w[2]^w[3]^w[4] ; w[11] = w[10]^w[5] ; = SubWord(RotWord(w[5]))^Rcon^w[0]^w[1]^w[2]^w[3]^w[4]^w[5] ; w[12] = SubWord(RotWord(w[11]))^Rcon^w[6] ; w[13] = w[12]^w[7] ; = SubWord(RotWord(w[11]))^Rcon^w[6]^w[7] ; w[14] = w[13]^w[8] ; = SubWord(RotWord(w[11]))^Rcon^w[6]^w[7]^w[8] ; w[15] = w[14]^w[9] ; = SubWord(RotWord(w[11]))^Rcon^w[6]^w[7]^w[8]^w[9] ; w[16] = w[15]^w[10] ; = SubWord(RotWord(w[11]))^Rcon^w[6]^w[7]^w[8]^w[9]^w[10] ; w[17] = w[16]^w[11] ; = SubWort(RotWord(w[11]))^Rcon^w[6]^w[7]^w[8]^w[9]^w[10]^w[11] ; ; ... and so on. ; ; The Intel AES-NI instruction set facilitates calculating SubWord ; and RotWord using `aeskeygenassist`, which is used in this routine. ; ; Preconditions: ; * xmm2[63:32] == w[5], ; * xmm2[31:0] == w[4], ; * xmm1[127:96] == w[3], ; * xmm1[95:64] == w[2], ; * xmm1[63:32] == w[1], ; * xmm1[31:0] == w[0]. movdqa [key_schedule], xmm1 ; sets w[0], w[1], w[2], w[3] movdqa [key_schedule + 10h], xmm2 ; sets w[4], w[5] lea ecx, [key_schedule + 18h] ; ecx = &w[6] aeskeygenassist xmm7, xmm2, 1 ; xmm7[63:32] = RotWord(SubWord(w[5]))^Rcon, call gen_round_key ; sets w[6], w[7], w[8], w[9], w[10], w[11] aeskeygenassist xmm7, xmm2, 2 ; xmm7[63:32] = RotWord(SubWord(w[11]))^Rcon call gen_round_key ; sets w[12], w[13], w[14], w[15], w[16], w[17] aeskeygenassist xmm7, xmm2, 4 ; xmm7[63:32] = RotWord(SubWord(w[17]))^Rcon call gen_round_key ; sets w[18], w[19], w[20], w[21], w[22], w[23] aeskeygenassist xmm7, xmm2, 8 ; xmm7[63:32] = RotWord(SubWord(w[23]))^Rcon call gen_round_key ; sets w[24], w[25], w[26], w[27], w[28], w[29] aeskeygenassist xmm7, xmm2, 10h ; xmm7[63:32] = RotWord(SubWord(w[29]))^Rcon call gen_round_key ; sets w[30], w[31], w[32], w[33], w[34], w[35] aeskeygenassist xmm7, xmm2, 20h ; xmm7[63:32] = RotWord(SubWord(w[35]))^Rcon call gen_round_key ; sets w[36], w[37], w[38], w[39], w[40], w[41] aeskeygenassist xmm7, xmm2, 40h ; xmm7[63:32] = RotWord(SubWord(w[41]))^Rcon call gen_round_key ; sets w[42], w[43], w[44], w[45], w[46], w[47] aeskeygenassist xmm7, xmm2, 80h ; xmm7[63:32] = RotWord(SubWord(w[49]))^Rcon call gen_round_key ; sets w[48], w[49], w[50], w[51], w[52], w[53] // FIXME call invert_key_schedule ret gen_round_key: ; Preconditions: ; * xmm2[127:96] == 0, ; * xmm2[95:64] == 0, ; * xmm2[63:32] == w[i+5], ; * xmm2[31:0] == w[i+4], ; * xmm1[127:96] == w[i+3], ; * xmm1[95:64] == w[i+2], ; * xmm1[63:32] == w[i+1], ; * xmm1[31:0] == w[i], ; * xmm7[63:32] == RotWord(SubWord(w[i+5]))^Rcon, ; * ecx == &w[i+6]. ; ; Postconditions: ; * xmm2[127:96] == 0, ; * xmm2[95:64] == 0, ; * xmm2[63:32] == w[i+11] == RotWord(SubWord(w[i+5]))^Rcon^w[i+5]^w[i+4]^w[i+3]^w[i+2]^w[i+1]^w[i], ; * xmm2[31:0] == w[i+10] == RotWord(SubWord(w[i+5]))^Rcon^w[i+4]^w[i+3]^w[i+2]^w[i+1]^w[i], ; * xmm1[127:96] == w[i+9] == RotWord(SubWord(w[i+5]))^Rcon^w[i+3]^w[i+2]^w[i+1]^w[i], ; * xmm1[95:64] == w[i+8] == RotWord(SubWord(w[i+5]))^Rcon^w[i+2]^w[i+1]^w[i], ; * xmm1[63:32] == w[i+7] == RotWord(SubWord(w[i+5]))^Rcon^w[i+1]^w[i], ; * xmm1[31:0] == w[i+6] == RotWord(SubWord(w[i+5]))^Rcon^w[i], ; * ecx == &w[i+12], ; * the value in xmm6 is also modified. ; Calculate ; w[i+3]^w[i+2]^w[i+1]^w[i], ; w[i+2]^w[i+1]^w[i], ; w[i+1]^w[i] and ; w[i]. movdqa xmm6, xmm1 ; xmm6 = xmm1 pslldq xmm6, 4 ; xmm6 <<= 32 pxor xmm1, xmm6 ; xmm1 ^= xmm6 pslldq xmm6, 4 ; xmm6 <<= 32 pxor xmm1, xmm6 ; xmm1 ^= xmm6 pslldq xmm6, 4 ; xmm6 <<= 32 pxor xmm1, xmm6 ; xmm1 ^= xmm6 ; xmm1[127:96] == w[i+3]^w[i+2]^w[i+1]^w[i] ; xmm1[95:64] == w[i+2]^w[i+1]^w[i] ; xmm1[63:32] == w[i+1]^w[i] ; xmm1[31:0] == w[i] ; Calculate ; w[i+9] == RotWord(SubWord(w[i+5]))^Rcon^w[i+3]^w[i+2]^w[i+1]^w[i], ; w[i+8] == RotWord(SubWord(w[i+5]))^Rcon^w[i+2]^w[i+1]^w[i], ; w[i+7] == RotWord(SubWord(w[i+5]))^Rcon^w[i+1]^w[i] and ; w[i+6] == RotWord(SubWord(w[i+5]))^Rcon^w[i]. pshufd xmm6, xmm7, 55h ; xmm6[127:96] = xmm6[95:64] = xmm6[63:32] = xmm6[31:0] = xmm7[63:32] pxor xmm1, xmm6 ; xmm1 ^= xmm6 ; xmm1[127:96] == w[i+9] == RotWord(SubWord(w[i+5]))^Rcon^w[i+3]^w[i+2]^w[i+1]^w[i] ; xmm1[95:64] == w[i+8] == RotWord(SubWord(w[i+5]))^Rcon^w[i+2]^w[i+1]^w[i] ; xmm1[63:32] == w[i+7] == RotWord(SubWord(w[i+5]))^Rcon^w[i+1]^w[i] ; xmm1[31:0] == w[i+6] == RotWord(SubWord(w[i+5]))^Rcon^w[i] ; Set w[i+6], w[i+7], w[i+8] and w[i+9]. movdqu [ecx], xmm1 ; w[i+6] = RotWord(SubWord(w[i+5]))^Rcon^w[i] ; w[i+7] = RotWord(SubWord(w[i+5]))^Rcon^w[i+1]^w[i] ; w[i+8] = RotWord(SubWord(w[i+5]))^Rcon^w[i+2]^w[i+1]^w[i] ; w[i+9] = RotWord(SubWord(w[i+5]))^Rcon^w[i+3]^w[i+2]^w[i+1]^w[i] add ecx, 10h ; ecx = &w[i+10] ; Calculate ; w[i+5]^w[i+4], ; w[i+4]. pshufd xmm6, xmm2, 0F3h ; xmm6 = xmm2[31:0] << 32 pxor xmm2, xmm6 ; xmm2 ^= xmm7 ; xmm2[63:32] == w[i+5]^w[i+4] ; xmm2[31:0] == w[i+4] ; Calculate ; w[i+10] == RotWord(SubWord(w[i+5]))^Rcon^w[i+5]^w[i+4]^w[i+3]^w[i+2]^w[i+1]^w[i], ; w[i+11] == RotWord(SubWord(w[i+5]))^Rcon^w[i+4]^w[i+3]^w[i+2]^w[i+1]^w[i]. pshufd xmm6, xmm1, 0FFh ; xmm6[127:96] = xmm6[95:64] = xmm6[63:32] = xmm6[31:0] = xmm1[127:96] psrldq xmm6, 8 ; xmm6 >>= 64 pxor xmm2, xmm6 ; xmm2 ^= xmm6 ; xmm2[63:32] == w[i+11] == RotWord(SubWord(w[i+5]))^Rcon^w[i+5]^w[i+4]^w[i+3]^w[i+2]^w[i+1]^w[i] ; xmm2[31:0] == w[i+10] == RotWord(SubWord(w[i+5]))^Rcon^w[i+4]^w[i+3]^w[i+2]^w[i+1]^w[i] ; Set w[i+10] and w[i+11]. movq qword ptr [ecx], xmm2 ; w[i+10] = RotWord(SubWord(w[i+5]))^Rcon^w[i+4]^w[i+3]^w[i+2]^w[i+1]^w[i] ; w[i+11] = RotWord(SubWord(w[i+5]))^Rcon^w[i+5]^w[i+4]^w[i+3]^w[i+2]^w[i+1]^w[i] add ecx, 8 ; ecx = &w[i+12] ret invert_key_schedule: movdqa xmm7, [key_schedule] movdqa xmm6, [key_schedule + 0C0h] movdqa [inverted_key_schedule], xmm6 movdqa [inverted_key_schedule + 0C0h], xmm7 aesimc xmm7, [key_schedule + 10h] aesimc xmm6, [key_schedule + 0B0h] movdqa [inverted_key_schedule + 10h], xmm6 movdqa [inverted_key_schedule + 0B0h], xmm7 aesimc xmm7, [key_schedule + 20h] aesimc xmm6, [key_schedule + 0A0h] movdqa [inverted_key_schedule + 20h], xmm6 movdqa [inverted_key_schedule + 0A0h], xmm7 aesimc xmm7, [key_schedule + 30h] aesimc xmm6, [key_schedule + 90h] movdqa [inverted_key_schedule + 30h], xmm6 movdqa [inverted_key_schedule + 90h], xmm7 aesimc xmm7, [key_schedule + 40h] aesimc xmm6, [key_schedule + 80h] movdqa [inverted_key_schedule + 40h], xmm6 movdqa [inverted_key_schedule + 80h], xmm7 aesimc xmm7, [key_schedule + 50h] aesimc xmm6, [key_schedule + 70h] movdqa [inverted_key_schedule + 50h], xmm6 movdqa [inverted_key_schedule + 70h], xmm7 aesimc xmm7, [key_schedule + 60h] movdqa [inverted_key_schedule + 60h], xmm7 ret expand_keys192 endp end