/* * AES implementation based on code from BearSSL (https://bearssl.org/) * by Thomas Pornin. * * * Copyright (c) 2016 Thomas Pornin * * Permission is hereby granted, free of charge, to any person obtaining * a copy of this software and associated documentation files (the * "Software"), to deal in the Software without restriction, including * without limitation the rights to use, copy, modify, merge, publish, * distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so, subject to * the following conditions: * * The above copyright notice and this permission notice shall be * included in all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE * SOFTWARE. */ #include #include #include "aes.h" static inline uint32_t br_dec32le(const unsigned char *src) { return (uint32_t)src[0] | ((uint32_t)src[1] << 8) | ((uint32_t)src[2] << 16) | ((uint32_t)src[3] << 24); } static void br_range_dec32le(uint32_t *v, size_t num, const unsigned char *src) { while (num-- > 0) { *v ++ = br_dec32le(src); src += 4; } } static inline uint32_t br_swap32(uint32_t x) { x = ((x & (uint32_t)0x00FF00FF) << 8) | ((x >> 8) & (uint32_t)0x00FF00FF); return (x << 16) | (x >> 16); } static inline void br_enc32le(unsigned char *dst, uint32_t x) { dst[0] = (unsigned char)x; dst[1] = (unsigned char)(x >> 8); dst[2] = (unsigned char)(x >> 16); dst[3] = (unsigned char)(x >> 24); } static void br_range_enc32le(unsigned char *dst, const uint32_t *v, size_t num) { while (num-- > 0) { br_enc32le(dst, *v ++); dst += 4; } } static void br_aes_ct64_bitslice_Sbox(uint64_t *q) { /* * This S-box implementation is a straightforward translation of * the circuit described by Boyar and Peralta in "A new * combinational logic minimization technique with applications * to cryptology" (https://eprint.iacr.org/2009/191.pdf). * * Note that variables x* (input) and s* (output) are numbered * in "reverse" order (x0 is the high bit, x7 is the low bit). */ uint64_t x0, x1, x2, x3, x4, x5, x6, x7; uint64_t y1, y2, y3, y4, y5, y6, y7, y8, y9; uint64_t y10, y11, y12, y13, y14, y15, y16, y17, y18, y19; uint64_t y20, y21; uint64_t z0, z1, z2, z3, z4, z5, z6, z7, z8, z9; uint64_t z10, z11, z12, z13, z14, z15, z16, z17; uint64_t t0, t1, t2, t3, t4, t5, t6, t7, t8, t9; uint64_t t10, t11, t12, t13, t14, t15, t16, t17, t18, t19; uint64_t t20, t21, t22, t23, t24, t25, t26, t27, t28, t29; uint64_t t30, t31, t32, t33, t34, t35, t36, t37, t38, t39; uint64_t t40, t41, t42, t43, t44, t45, t46, t47, t48, t49; uint64_t t50, t51, t52, t53, t54, t55, t56, t57, t58, t59; uint64_t t60, t61, t62, t63, t64, t65, t66, t67; uint64_t s0, s1, s2, s3, s4, s5, s6, s7; x0 = q[7]; x1 = q[6]; x2 = q[5]; x3 = q[4]; x4 = q[3]; x5 = q[2]; x6 = q[1]; x7 = q[0]; /* * Top linear transformation. */ y14 = x3 ^ x5; y13 = x0 ^ x6; y9 = x0 ^ x3; y8 = x0 ^ x5; t0 = x1 ^ x2; y1 = t0 ^ x7; y4 = y1 ^ x3; y12 = y13 ^ y14; y2 = y1 ^ x0; y5 = y1 ^ x6; y3 = y5 ^ y8; t1 = x4 ^ y12; y15 = t1 ^ x5; y20 = t1 ^ x1; y6 = y15 ^ x7; y10 = y15 ^ t0; y11 = y20 ^ y9; y7 = x7 ^ y11; y17 = y10 ^ y11; y19 = y10 ^ y8; y16 = t0 ^ y11; y21 = y13 ^ y16; y18 = x0 ^ y16; /* * Non-linear section. */ t2 = y12 & y15; t3 = y3 & y6; t4 = t3 ^ t2; t5 = y4 & x7; t6 = t5 ^ t2; t7 = y13 & y16; t8 = y5 & y1; t9 = t8 ^ t7; t10 = y2 & y7; t11 = t10 ^ t7; t12 = y9 & y11; t13 = y14 & y17; t14 = t13 ^ t12; t15 = y8 & y10; t16 = t15 ^ t12; t17 = t4 ^ t14; t18 = t6 ^ t16; t19 = t9 ^ t14; t20 = t11 ^ t16; t21 = t17 ^ y20; t22 = t18 ^ y19; t23 = t19 ^ y21; t24 = t20 ^ y18; t25 = t21 ^ t22; t26 = t21 & t23; t27 = t24 ^ t26; t28 = t25 & t27; t29 = t28 ^ t22; t30 = t23 ^ t24; t31 = t22 ^ t26; t32 = t31 & t30; t33 = t32 ^ t24; t34 = t23 ^ t33; t35 = t27 ^ t33; t36 = t24 & t35; t37 = t36 ^ t34; t38 = t27 ^ t36; t39 = t29 & t38; t40 = t25 ^ t39; t41 = t40 ^ t37; t42 = t29 ^ t33; t43 = t29 ^ t40; t44 = t33 ^ t37; t45 = t42 ^ t41; z0 = t44 & y15; z1 = t37 & y6; z2 = t33 & x7; z3 = t43 & y16; z4 = t40 & y1; z5 = t29 & y7; z6 = t42 & y11; z7 = t45 & y17; z8 = t41 & y10; z9 = t44 & y12; z10 = t37 & y3; z11 = t33 & y4; z12 = t43 & y13; z13 = t40 & y5; z14 = t29 & y2; z15 = t42 & y9; z16 = t45 & y14; z17 = t41 & y8; /* * Bottom linear transformation. */ t46 = z15 ^ z16; t47 = z10 ^ z11; t48 = z5 ^ z13; t49 = z9 ^ z10; t50 = z2 ^ z12; t51 = z2 ^ z5; t52 = z7 ^ z8; t53 = z0 ^ z3; t54 = z6 ^ z7; t55 = z16 ^ z17; t56 = z12 ^ t48; t57 = t50 ^ t53; t58 = z4 ^ t46; t59 = z3 ^ t54; t60 = t46 ^ t57; t61 = z14 ^ t57; t62 = t52 ^ t58; t63 = t49 ^ t58; t64 = z4 ^ t59; t65 = t61 ^ t62; t66 = z1 ^ t63; s0 = t59 ^ t63; s6 = t56 ^ ~t62; s7 = t48 ^ ~t60; t67 = t64 ^ t65; s3 = t53 ^ t66; s4 = t51 ^ t66; s5 = t47 ^ t65; s1 = t64 ^ ~s3; s2 = t55 ^ ~t67; q[7] = s0; q[6] = s1; q[5] = s2; q[4] = s3; q[3] = s4; q[2] = s5; q[1] = s6; q[0] = s7; } static void br_aes_ct64_ortho(uint64_t *q) { #define SWAPN(cl, ch, s, x, y) do { \ uint64_t a, b; \ a = (x); \ b = (y); \ (x) = (a & (uint64_t)(cl)) | ((b & (uint64_t)(cl)) << (s)); \ (y) = ((a & (uint64_t)(ch)) >> (s)) | (b & (uint64_t)(ch)); \ } while (0) #define SWAP2(x, y) SWAPN(0x5555555555555555, 0xAAAAAAAAAAAAAAAA, 1, x, y) #define SWAP4(x, y) SWAPN(0x3333333333333333, 0xCCCCCCCCCCCCCCCC, 2, x, y) #define SWAP8(x, y) SWAPN(0x0F0F0F0F0F0F0F0F, 0xF0F0F0F0F0F0F0F0, 4, x, y) SWAP2(q[0], q[1]); SWAP2(q[2], q[3]); SWAP2(q[4], q[5]); SWAP2(q[6], q[7]); SWAP4(q[0], q[2]); SWAP4(q[1], q[3]); SWAP4(q[4], q[6]); SWAP4(q[5], q[7]); SWAP8(q[0], q[4]); SWAP8(q[1], q[5]); SWAP8(q[2], q[6]); SWAP8(q[3], q[7]); } static void br_aes_ct64_interleave_in(uint64_t *q0, uint64_t *q1, const uint32_t *w) { uint64_t x0, x1, x2, x3; x0 = w[0]; x1 = w[1]; x2 = w[2]; x3 = w[3]; x0 |= (x0 << 16); x1 |= (x1 << 16); x2 |= (x2 << 16); x3 |= (x3 << 16); x0 &= (uint64_t)0x0000FFFF0000FFFF; x1 &= (uint64_t)0x0000FFFF0000FFFF; x2 &= (uint64_t)0x0000FFFF0000FFFF; x3 &= (uint64_t)0x0000FFFF0000FFFF; x0 |= (x0 << 8); x1 |= (x1 << 8); x2 |= (x2 << 8); x3 |= (x3 << 8); x0 &= (uint64_t)0x00FF00FF00FF00FF; x1 &= (uint64_t)0x00FF00FF00FF00FF; x2 &= (uint64_t)0x00FF00FF00FF00FF; x3 &= (uint64_t)0x00FF00FF00FF00FF; *q0 = x0 | (x2 << 8); *q1 = x1 | (x3 << 8); } static void br_aes_ct64_interleave_out(uint32_t *w, uint64_t q0, uint64_t q1) { uint64_t x0, x1, x2, x3; x0 = q0 & (uint64_t)0x00FF00FF00FF00FF; x1 = q1 & (uint64_t)0x00FF00FF00FF00FF; x2 = (q0 >> 8) & (uint64_t)0x00FF00FF00FF00FF; x3 = (q1 >> 8) & (uint64_t)0x00FF00FF00FF00FF; x0 |= (x0 >> 8); x1 |= (x1 >> 8); x2 |= (x2 >> 8); x3 |= (x3 >> 8); x0 &= (uint64_t)0x0000FFFF0000FFFF; x1 &= (uint64_t)0x0000FFFF0000FFFF; x2 &= (uint64_t)0x0000FFFF0000FFFF; x3 &= (uint64_t)0x0000FFFF0000FFFF; w[0] = (uint32_t)x0 | (uint32_t)(x0 >> 16); w[1] = (uint32_t)x1 | (uint32_t)(x1 >> 16); w[2] = (uint32_t)x2 | (uint32_t)(x2 >> 16); w[3] = (uint32_t)x3 | (uint32_t)(x3 >> 16); } static const unsigned char Rcon[] = { 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1B, 0x36 }; static uint32_t sub_word(uint32_t x) { uint64_t q[8]; memset(q, 0, sizeof q); q[0] = x; br_aes_ct64_ortho(q); br_aes_ct64_bitslice_Sbox(q); br_aes_ct64_ortho(q); return (uint32_t)q[0]; } static void br_aes_ct64_keysched(uint64_t *comp_skey, const unsigned char *key, unsigned int key_len) { unsigned int i, j, k, nk, nkf; uint32_t tmp; uint32_t skey[60]; unsigned nrounds = 10 + ((key_len - 16) >> 2); nk = (key_len >> 2); nkf = ((nrounds + 1) << 2); br_range_dec32le(skey, (key_len >> 2), key); tmp = skey[(key_len >> 2) - 1]; for (i = nk, j = 0, k = 0; i < nkf; i ++) { if (j == 0) { tmp = (tmp << 24) | (tmp >> 8); tmp = sub_word(tmp) ^ Rcon[k]; } else if (nk > 6 && j == 4) { tmp = sub_word(tmp); } tmp ^= skey[i - nk]; skey[i] = tmp; if (++ j == nk) { j = 0; k ++; } } for (i = 0, j = 0; i < nkf; i += 4, j += 2) { uint64_t q[8]; br_aes_ct64_interleave_in(&q[0], &q[4], skey + i); q[1] = q[0]; q[2] = q[0]; q[3] = q[0]; q[5] = q[4]; q[6] = q[4]; q[7] = q[4]; br_aes_ct64_ortho(q); comp_skey[j + 0] = (q[0] & (uint64_t)0x1111111111111111) | (q[1] & (uint64_t)0x2222222222222222) | (q[2] & (uint64_t)0x4444444444444444) | (q[3] & (uint64_t)0x8888888888888888); comp_skey[j + 1] = (q[4] & (uint64_t)0x1111111111111111) | (q[5] & (uint64_t)0x2222222222222222) | (q[6] & (uint64_t)0x4444444444444444) | (q[7] & (uint64_t)0x8888888888888888); } } static void br_aes_ct64_skey_expand(uint64_t *skey, const uint64_t *comp_skey, unsigned int nrounds) { unsigned u, v, n; n = (nrounds + 1) << 1; for (u = 0, v = 0; u < n; u ++, v += 4) { uint64_t x0, x1, x2, x3; x0 = x1 = x2 = x3 = comp_skey[u]; x0 &= (uint64_t)0x1111111111111111; x1 &= (uint64_t)0x2222222222222222; x2 &= (uint64_t)0x4444444444444444; x3 &= (uint64_t)0x8888888888888888; x1 >>= 1; x2 >>= 2; x3 >>= 3; skey[v + 0] = (x0 << 4) - x0; skey[v + 1] = (x1 << 4) - x1; skey[v + 2] = (x2 << 4) - x2; skey[v + 3] = (x3 << 4) - x3; } } static inline void add_round_key(uint64_t *q, const uint64_t *sk) { q[0] ^= sk[0]; q[1] ^= sk[1]; q[2] ^= sk[2]; q[3] ^= sk[3]; q[4] ^= sk[4]; q[5] ^= sk[5]; q[6] ^= sk[6]; q[7] ^= sk[7]; } static inline void shift_rows(uint64_t *q) { int i; for (i = 0; i < 8; i ++) { uint64_t x; x = q[i]; q[i] = (x & (uint64_t)0x000000000000FFFF) | ((x & (uint64_t)0x00000000FFF00000) >> 4) | ((x & (uint64_t)0x00000000000F0000) << 12) | ((x & (uint64_t)0x0000FF0000000000) >> 8) | ((x & (uint64_t)0x000000FF00000000) << 8) | ((x & (uint64_t)0xF000000000000000) >> 12) | ((x & (uint64_t)0x0FFF000000000000) << 4); } } static inline uint64_t rotr32(uint64_t x) { return (x << 32) | (x >> 32); } static inline void mix_columns(uint64_t *q) { uint64_t q0, q1, q2, q3, q4, q5, q6, q7; uint64_t r0, r1, r2, r3, r4, r5, r6, r7; q0 = q[0]; q1 = q[1]; q2 = q[2]; q3 = q[3]; q4 = q[4]; q5 = q[5]; q6 = q[6]; q7 = q[7]; r0 = (q0 >> 16) | (q0 << 48); r1 = (q1 >> 16) | (q1 << 48); r2 = (q2 >> 16) | (q2 << 48); r3 = (q3 >> 16) | (q3 << 48); r4 = (q4 >> 16) | (q4 << 48); r5 = (q5 >> 16) | (q5 << 48); r6 = (q6 >> 16) | (q6 << 48); r7 = (q7 >> 16) | (q7 << 48); q[0] = q7 ^ r7 ^ r0 ^ rotr32(q0 ^ r0); q[1] = q0 ^ r0 ^ q7 ^ r7 ^ r1 ^ rotr32(q1 ^ r1); q[2] = q1 ^ r1 ^ r2 ^ rotr32(q2 ^ r2); q[3] = q2 ^ r2 ^ q7 ^ r7 ^ r3 ^ rotr32(q3 ^ r3); q[4] = q3 ^ r3 ^ q7 ^ r7 ^ r4 ^ rotr32(q4 ^ r4); q[5] = q4 ^ r4 ^ r5 ^ rotr32(q5 ^ r5); q[6] = q5 ^ r5 ^ r6 ^ rotr32(q6 ^ r6); q[7] = q6 ^ r6 ^ r7 ^ rotr32(q7 ^ r7); } static void inc4_be(uint32_t *x) { uint32_t t = br_swap32(*x) + 4; *x = br_swap32(t); } static void aes_ecb4x(unsigned char out[64], const uint32_t ivw[16], const uint64_t *sk_exp, unsigned int nrounds) { uint32_t w[16]; uint64_t q[8]; unsigned int i; memcpy(w, ivw, sizeof(w)); for (i = 0; i < 4; i++) { br_aes_ct64_interleave_in(&q[i], &q[i + 4], w + (i << 2)); } br_aes_ct64_ortho(q); add_round_key(q, sk_exp); for (i = 1; i < nrounds; i++) { br_aes_ct64_bitslice_Sbox(q); shift_rows(q); mix_columns(q); add_round_key(q, sk_exp + (i << 3)); } br_aes_ct64_bitslice_Sbox(q); shift_rows(q); add_round_key(q, sk_exp + 8 * nrounds); br_aes_ct64_ortho(q); for (i = 0; i < 4; i ++) { br_aes_ct64_interleave_out(w + (i << 2), q[i], q[i + 4]); } br_range_enc32le(out, w, 16); } static void aes_ctr4x(unsigned char out[64], uint32_t ivw[16], const uint64_t *sk_exp, unsigned int nrounds) { aes_ecb4x(out, ivw, sk_exp, nrounds); /* Increase counter for next 4 blocks */ inc4_be(ivw + 3); inc4_be(ivw + 7); inc4_be(ivw + 11); inc4_be(ivw + 15); } static void aes_ecb(unsigned char *out, const unsigned char *in, size_t nblocks, const uint64_t *rkeys, unsigned int nrounds) { uint32_t blocks[16]; unsigned char t[64]; while (nblocks >= 4) { br_range_dec32le(blocks, 16, in); aes_ecb4x(out, blocks, rkeys, nrounds); nblocks -= 4; in += 64; out += 64; } if (nblocks) { br_range_dec32le(blocks, nblocks * 4, in); aes_ecb4x(t, blocks, rkeys, nrounds); memcpy(out, t, nblocks * 16); } } static void aes_ctr(unsigned char *out, size_t outlen, const unsigned char *iv, const uint64_t *rkeys, unsigned int nrounds) { uint32_t ivw[16]; size_t i; uint32_t cc = 0; br_range_dec32le(ivw, 3, iv); memcpy(ivw + 4, ivw, 3 * sizeof(uint32_t)); memcpy(ivw + 8, ivw, 3 * sizeof(uint32_t)); memcpy(ivw + 12, ivw, 3 * sizeof(uint32_t)); ivw[ 3] = br_swap32(cc); ivw[ 7] = br_swap32(cc + 1); ivw[11] = br_swap32(cc + 2); ivw[15] = br_swap32(cc + 3); while (outlen > 64) { aes_ctr4x(out, ivw, rkeys, nrounds); out += 64; outlen -= 64; } if (outlen > 0) { unsigned char tmp[64]; aes_ctr4x(tmp, ivw, rkeys, nrounds); for (i = 0; i < outlen; i++) { out[i] = tmp[i]; } } } void aes128_ecb_keyexp(aes128ctx *r, const unsigned char *key) { uint64_t skey[22]; br_aes_ct64_keysched(skey, key, 16); br_aes_ct64_skey_expand(r->sk_exp, skey, 10); } void aes128_ctr_keyexp(aes128ctx *r, const unsigned char *key) { aes128_ecb_keyexp(r, key); } void aes192_ecb_keyexp(aes192ctx *r, const unsigned char *key) { uint64_t skey[26]; br_aes_ct64_keysched(skey, key, 24); br_aes_ct64_skey_expand(r->sk_exp, skey, 12); } void aes192_ctr_keyexp(aes192ctx *r, const unsigned char *key) { aes192_ecb_keyexp(r, key); } void aes256_ecb_keyexp(aes256ctx *r, const unsigned char *key) { uint64_t skey[30]; br_aes_ct64_keysched(skey, key, 32); br_aes_ct64_skey_expand(r->sk_exp, skey, 14); } void aes256_ctr_keyexp(aes256ctx *r, const unsigned char *key) { aes256_ecb_keyexp(r, key); } void aes128_ecb(unsigned char *out, const unsigned char *in, size_t nblocks, const aes128ctx *ctx) { aes_ecb(out, in, nblocks, ctx->sk_exp, 10); } void aes128_ctr(unsigned char *out, size_t outlen, const unsigned char *iv, const aes128ctx *ctx) { aes_ctr(out, outlen, iv, ctx->sk_exp, 10); } void aes192_ecb(unsigned char *out, const unsigned char *in, size_t nblocks, const aes192ctx *ctx) { aes_ecb(out, in, nblocks, ctx->sk_exp, 12); } void aes192_ctr(unsigned char *out, size_t outlen, const unsigned char *iv, const aes192ctx *ctx) { aes_ctr(out, outlen, iv, ctx->sk_exp, 12); } void aes256_ecb(unsigned char *out, const unsigned char *in, size_t nblocks, const aes256ctx *ctx) { aes_ecb(out, in, nblocks, ctx->sk_exp, 14); } void aes256_ctr(unsigned char *out, size_t outlen, const unsigned char *iv, const aes256ctx *ctx) { aes_ctr(out, outlen, iv, ctx->sk_exp, 14); } void aes128_ctx_release(aes128ctx *r) { (void)r; } void aes192_ctx_release(aes192ctx *r) { (void)r; } void aes256_ctx_release(aes256ctx *r) { (void)r; }