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author | Egor Tensin <Egor.Tensin@gmail.com> | 2019-12-21 13:33:50 +0300 |
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committer | Egor Tensin <Egor.Tensin@gmail.com> | 2019-12-21 13:33:50 +0300 |
commit | 351c5188013fff041c7217aed64478cfc7643480 (patch) | |
tree | c918b5093ac45394439f3dff30da37b809173603 /aes/src/asm/aes128.asm | |
parent | cmake: install libraries & their headers (diff) | |
download | aes-tools-351c5188013fff041c7217aed64478cfc7643480.tar.gz aes-tools-351c5188013fff041c7217aed64478cfc7643480.zip |
restructure the project
Diffstat (limited to 'aes/src/asm/aes128.asm')
-rw-r--r-- | aes/src/asm/aes128.asm | 203 |
1 files changed, 203 insertions, 0 deletions
diff --git a/aes/src/asm/aes128.asm b/aes/src/asm/aes128.asm new file mode 100644 index 0000000..80be57c --- /dev/null +++ b/aes/src/asm/aes128.asm @@ -0,0 +1,203 @@ +; Copyright (c) 2015 Egor Tensin <Egor.Tensin@gmail.com> +; This file is part of the "AES tools" project. +; For details, see https://github.com/egor-tensin/aes-tools. +; Distributed under the MIT License. + +.586 +.xmm +.model flat + +.code + +@aes_AES128_encrypt_block_@20 proc + pxor xmm0, [ecx] + aesenc xmm0, [ecx + 10h] + aesenc xmm0, [ecx + 20h] + aesenc xmm0, [ecx + 30h] + aesenc xmm0, [ecx + 40h] + aesenc xmm0, [ecx + 50h] + aesenc xmm0, [ecx + 60h] + aesenc xmm0, [ecx + 70h] + aesenc xmm0, [ecx + 80h] + aesenc xmm0, [ecx + 90h] + aesenclast xmm0, [ecx + 0A0h] + ret +@aes_AES128_encrypt_block_@20 endp + +@aes_AES128_decrypt_block_@20 proc + pxor xmm0, [ecx] + aesdec xmm0, [ecx + 10h] + aesdec xmm0, [ecx + 20h] + aesdec xmm0, [ecx + 30h] + aesdec xmm0, [ecx + 40h] + aesdec xmm0, [ecx + 50h] + aesdec xmm0, [ecx + 60h] + aesdec xmm0, [ecx + 70h] + aesdec xmm0, [ecx + 80h] + aesdec xmm0, [ecx + 90h] + aesdeclast xmm0, [ecx + 0A0h] + ret +@aes_AES128_decrypt_block_@20 endp + +@aes_AES128_expand_key_@20 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 10 "regular" keys and a dumb key for + ; the "whitening" step. + ; + ; A key schedule is thus composed of 44 "words". + ; The FIPS standard includes an algorithm to calculate these words via + ; a simple loop: + ; + ; i = 4 + ; while i < 44: + ; temp = w[i - 1] + ; if i % 4 == 0: + ; temp = SubWord(RotWord(temp))^Rcon + ; w[i] = w[i - 4]^temp + ; i = i + 1 + ; + ; The loop above may be unrolled like this: + ; + ; w[4] = SubWord(RotWord(w[3]))^Rcon^w[0] + ; w[5] = w[4]^w[1] + ; = SubWord(RotWord(w[3]))^Rcon^w[1]^w[0] + ; w[6] = w[5]^w[2] + ; = SubWord(RotWord(w[3]))^Rcon^w[2]^w[1]^w[0] + ; w[7] = w[6]^w[3] + ; = SubWord(RotWord(w[3]))^Rcon^w[3]^w[2]^w[1]^w[0] + ; w[8] = SubWord(RotWord(w[7]))^Rcon^w[4] + ; w[9] = w[8]^w[5] + ; = SubWord(RotWord(w[7]))^Rcon^w[5]^w[4] + ; w[10] = w[9]^w[6] + ; = SubWord(RotWord(w[7]))^Rcon^w[6]^w[5]^w[4] + ; w[11] = w[10]^w[7] + ; = SubWord(RotWord(w[7]))^Rcon^w[7]^w[6]^w[5]^w[4] + ; + ; ... and so on. + ; + ; The Intel AES-NI instruction set facilitates calculating SubWord + ; and RotWord using `aeskeygenassist`, which is used in this routine. + ; + ; Preconditions: + ; * xmm0[127:96] == w[3], + ; * xmm0[95:64] == w[2], + ; * xmm0[63:32] == w[1], + ; * xmm0[31:0] == w[0]. + + movdqa [ecx], xmm0 ; sets w[0], w[1], w[2], w[3] + add ecx, 10h ; ecx = &w[4] + + aeskeygenassist xmm5, xmm0, 01h ; xmm5[127:96] = RotWord(SubWord(w[3]))^Rcon + call aes128_keygen_assist ; sets w[4], w[5], w[6], w[7] + aeskeygenassist xmm5, xmm0, 02h ; xmm5[127:96] = RotWord(SubWord(w[7]))^Rcon + call aes128_keygen_assist ; sets w[8], w[9], w[10], w[11] + aeskeygenassist xmm5, xmm0, 04h ; xmm5[127:96] = RotWord(SubWord(w[11]))^Rcon + call aes128_keygen_assist ; sets w[12], w[13], w[14], w[15] + aeskeygenassist xmm5, xmm0, 08h ; xmm5[127:96] = RotWord(SubWord(w[15]))^Rcon + call aes128_keygen_assist ; sets w[16], w[17], w[18], w[19] + aeskeygenassist xmm5, xmm0, 10h ; xmm5[127:96] = RotWord(SubWord(w[19]))^Rcon + call aes128_keygen_assist ; sets w[20], w[21], w[22], w[23] + aeskeygenassist xmm5, xmm0, 20h ; xmm5[127:96] = RotWord(SubWord(w[23]))^Rcon + call aes128_keygen_assist ; sets w[24], w[25], w[26], w[27] + aeskeygenassist xmm5, xmm0, 40h ; xmm5[127:96] = RotWord(SubWord(w[27]))^Rcon + call aes128_keygen_assist ; sets w[28], w[29], w[30], w[31] + aeskeygenassist xmm5, xmm0, 80h ; xmm5[127:96] = RotWord(SubWord(w[31]))^Rcon + call aes128_keygen_assist ; sets w[32], w[33], w[34], w[35] + aeskeygenassist xmm5, xmm0, 1Bh ; xmm5[127:96] = RotWord(SubWord(w[35]))^Rcon + call aes128_keygen_assist ; sets w[36], w[37], w[38], w[39] + aeskeygenassist xmm5, xmm0, 36h ; xmm5[127:96] = RotWord(SubWord(w[39]))^Rcon + call aes128_keygen_assist ; sets w[40], w[41], w[42], w[43] + + ret + +aes128_keygen_assist: + ; Preconditions: + ; * xmm0[127:96] == w[i+3], + ; * xmm0[95:64] == w[i+2], + ; * xmm0[63:32] == w[i+1], + ; * xmm0[31:0] == w[i], + ; * xmm5[127:96] == RotWord(SubWord(w[i+3]))^Rcon, + ; * ecx == &w[i+4]. + ; + ; Postconditions: + ; * xmm0[127:96] == w[i+7] == RotWord(SubWord(w[i+3]))^Rcon^w[i+3]^w[i+2]^w[i+1]^w[i], + ; * xmm0[95:64] == w[i+6] == RotWord(SubWord(w[i+3]))^Rcon^w[i+2]^w[i+1]^w[i], + ; * xmm0[63:32] == w[i+5] == RotWord(SubWord(w[i+3]))^Rcon^w[i+1]^w[i], + ; * xmm0[31:0] == w[i+4] == RotWord(SubWord(w[i+3]))^Rcon^w[i], + ; * ecx == &w[i+8], + ; * the value in xmm4 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 xmm4, xmm0 ; xmm4 = xmm0 + pslldq xmm4, 4 ; xmm4 <<= 32 + pxor xmm0, xmm4 ; xmm0 ^= xmm4 + pslldq xmm4, 4 ; xmm4 <<= 32 + pxor xmm0, xmm4 ; xmm0 ^= xmm4 + pslldq xmm4, 4 ; xmm4 <<= 32 + pxor xmm0, xmm4 ; xmm0 ^= xmm4 + ; xmm0[127:96] == w[i+3]^w[i+2]^w[i+1]^w[i] + ; xmm0[95:64] == w[i+2]^w[i+1]^w[i] + ; xmm0[63:32] == w[i+1]^w[i] + ; xmm0[31:0] == w[i] + + ; Calculate + ; w[i+7] == RotWord(SubWord(w[i+3]))^Rcon^w[i+3]^w[i+2]^w[i+1]^w[i], + ; w[i+6] == RotWord(SubWord(w[i+3]))^Rcon^w[i+2]^w[i+1]^w[i], + ; w[i+5] == RotWord(SubWord(w[i+3]))^Rcon^w[i+1]^w[i] and + ; w[i+4] == RotWord(SubWord(w[i+3]))^Rcon^w[i]. + pshufd xmm4, xmm5, 0FFh ; xmm4[127:96] = xmm4[95:64] = xmm4[63:32] = xmm4[31:0] = xmm5[127:96] + pxor xmm0, xmm4 ; xmm0 ^= xmm4 + ; xmm0[127:96] == w[i+7] == RotWord(SubWord(w[i+3]))^Rcon^w[i+3]^w[i+2]^w[i+1]^w[i] + ; xmm0[95:64] == w[i+6] == RotWord(SubWord(w[i+3]))^Rcon^w[i+2]^w[i+1]^w[i] + ; xmm0[63:32] == w[i+5] == RotWord(SubWord(w[i+3]))^Rcon^w[i+1]^w[i] + ; xmm0[31:0] == w[i+4] == RotWord(SubWord(w[i+3]))^Rcon^w[i] + + ; Set w[i+4], w[i+5], w[i+6] and w[i+7]. + movdqa [ecx], xmm0 ; w[i+7] = RotWord(SubWord(w[i+3]))^Rcon^w[i+3]^w[i+2]^w[i+1]^w[i] + ; w[i+6] = RotWord(SubWord(w[i+3]))^Rcon^w[i+2]^w[i+1]^w[i] + ; w[i+5] = RotWord(SubWord(w[i+3]))^Rcon^w[i+1]^w[i] + ; w[i+4] = RotWord(SubWord(w[i+3]))^Rcon^w[i] + add ecx, 10h ; ecx = &w[i+8] + + ret +@aes_AES128_expand_key_@20 endp + +@aes_AES128_derive_decryption_keys_@8 proc + movdqa xmm5, [ecx] + movdqa xmm4, [ecx + 0A0h] + movdqa [edx], xmm4 + movdqa [edx + 0A0h], xmm5 + + aesimc xmm5, [ecx + 10h] + aesimc xmm4, [ecx + 90h] + movdqa [edx + 10h], xmm4 + movdqa [edx + 90h], xmm5 + + aesimc xmm5, [ecx + 20h] + aesimc xmm4, [ecx + 80h] + movdqa [edx + 20h], xmm4 + movdqa [edx + 80h], xmm5 + + aesimc xmm5, [ecx + 30h] + aesimc xmm4, [ecx + 70h] + movdqa [edx + 30h], xmm4 + movdqa [edx + 70h], xmm5 + + aesimc xmm5, [ecx + 40h] + aesimc xmm4, [ecx + 60h] + movdqa [edx + 40h], xmm4 + movdqa [edx + 60h], xmm5 + + aesimc xmm5, [ecx + 50h] + movdqa [edx + 50h], xmm5 + + ret +@aes_AES128_derive_decryption_keys_@8 endp + +end |