| /* |
| * AES (Rijndael) cipher - encrypt |
| * |
| * Modifications to public domain implementation: |
| * - cleanup |
| * - use C pre-processor to make it easier to change S table access |
| * - added option (AES_SMALL_TABLES) for reducing code size by about 8 kB at |
| * cost of reduced throughput (quite small difference on Pentium 4, |
| * 10-25% when using -O1 or -O2 optimization) |
| * |
| * Copyright (c) 2003-2012, Jouni Malinen <j@w1.fi> |
| * |
| * This software may be distributed under the terms of the BSD license. |
| * See README for more details. |
| */ |
| |
| #include "includes.h" |
| |
| #include "common.h" |
| #include "crypto.h" |
| #include "aes_i.h" |
| |
| static void rijndaelEncrypt(const u32 rk[], int Nr, const u8 pt[16], u8 ct[16]) |
| { |
| u32 s0, s1, s2, s3, t0, t1, t2, t3; |
| #ifndef FULL_UNROLL |
| int r; |
| #endif /* ?FULL_UNROLL */ |
| |
| /* |
| * map byte array block to cipher state |
| * and add initial round key: |
| */ |
| s0 = GETU32(pt ) ^ rk[0]; |
| s1 = GETU32(pt + 4) ^ rk[1]; |
| s2 = GETU32(pt + 8) ^ rk[2]; |
| s3 = GETU32(pt + 12) ^ rk[3]; |
| |
| #define ROUND(i,d,s) \ |
| d##0 = TE0(s##0) ^ TE1(s##1) ^ TE2(s##2) ^ TE3(s##3) ^ rk[4 * i]; \ |
| d##1 = TE0(s##1) ^ TE1(s##2) ^ TE2(s##3) ^ TE3(s##0) ^ rk[4 * i + 1]; \ |
| d##2 = TE0(s##2) ^ TE1(s##3) ^ TE2(s##0) ^ TE3(s##1) ^ rk[4 * i + 2]; \ |
| d##3 = TE0(s##3) ^ TE1(s##0) ^ TE2(s##1) ^ TE3(s##2) ^ rk[4 * i + 3] |
| |
| #ifdef FULL_UNROLL |
| |
| ROUND(1,t,s); |
| ROUND(2,s,t); |
| ROUND(3,t,s); |
| ROUND(4,s,t); |
| ROUND(5,t,s); |
| ROUND(6,s,t); |
| ROUND(7,t,s); |
| ROUND(8,s,t); |
| ROUND(9,t,s); |
| if (Nr > 10) { |
| ROUND(10,s,t); |
| ROUND(11,t,s); |
| if (Nr > 12) { |
| ROUND(12,s,t); |
| ROUND(13,t,s); |
| } |
| } |
| |
| rk += Nr << 2; |
| |
| #else /* !FULL_UNROLL */ |
| |
| /* Nr - 1 full rounds: */ |
| r = Nr >> 1; |
| for (;;) { |
| ROUND(1,t,s); |
| rk += 8; |
| if (--r == 0) |
| break; |
| ROUND(0,s,t); |
| } |
| |
| #endif /* ?FULL_UNROLL */ |
| |
| #undef ROUND |
| |
| /* |
| * apply last round and |
| * map cipher state to byte array block: |
| */ |
| s0 = TE41(t0) ^ TE42(t1) ^ TE43(t2) ^ TE44(t3) ^ rk[0]; |
| PUTU32(ct , s0); |
| s1 = TE41(t1) ^ TE42(t2) ^ TE43(t3) ^ TE44(t0) ^ rk[1]; |
| PUTU32(ct + 4, s1); |
| s2 = TE41(t2) ^ TE42(t3) ^ TE43(t0) ^ TE44(t1) ^ rk[2]; |
| PUTU32(ct + 8, s2); |
| s3 = TE41(t3) ^ TE42(t0) ^ TE43(t1) ^ TE44(t2) ^ rk[3]; |
| PUTU32(ct + 12, s3); |
| } |
| |
| |
| void * aes_encrypt_init(const u8 *key, size_t len) |
| { |
| u32 *rk; |
| int res; |
| rk = os_malloc(AES_PRIV_SIZE); |
| if (rk == NULL) |
| return NULL; |
| res = rijndaelKeySetupEnc(rk, key, len * 8); |
| if (res < 0) { |
| os_free(rk); |
| return NULL; |
| } |
| rk[AES_PRIV_NR_POS] = res; |
| return rk; |
| } |
| |
| |
| void aes_encrypt(void *ctx, const u8 *plain, u8 *crypt) |
| { |
| u32 *rk = ctx; |
| rijndaelEncrypt(ctx, rk[AES_PRIV_NR_POS], plain, crypt); |
| } |
| |
| |
| void aes_encrypt_deinit(void *ctx) |
| { |
| os_memset(ctx, 0, AES_PRIV_SIZE); |
| os_free(ctx); |
| } |