18d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt/* 28d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt * AES-128 CBC 38d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt * 48d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt * Copyright (c) 2003-2007, Jouni Malinen <j@w1.fi> 58d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt * 6c5ec7f57ead87efa365800228aa0b09a12d9e6c4Dmitry Shmidt * This software may be distributed under the terms of the BSD license. 7c5ec7f57ead87efa365800228aa0b09a12d9e6c4Dmitry Shmidt * See README for more details. 88d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt */ 98d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt 108d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt#include "includes.h" 118d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt 128d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt#include "common.h" 138d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt#include "aes.h" 148d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt#include "aes_wrap.h" 158d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt 168d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt/** 178d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt * aes_128_cbc_encrypt - AES-128 CBC encryption 188d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt * @key: Encryption key 198d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt * @iv: Encryption IV for CBC mode (16 bytes) 208d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt * @data: Data to encrypt in-place 218d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt * @data_len: Length of data in bytes (must be divisible by 16) 228d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt * Returns: 0 on success, -1 on failure 238d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt */ 248d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidtint aes_128_cbc_encrypt(const u8 *key, const u8 *iv, u8 *data, size_t data_len) 258d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt{ 268d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt void *ctx; 278d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt u8 cbc[AES_BLOCK_SIZE]; 288d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt u8 *pos = data; 298d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt int i, j, blocks; 308d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt 318d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt ctx = aes_encrypt_init(key, 16); 328d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt if (ctx == NULL) 338d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt return -1; 348d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt os_memcpy(cbc, iv, AES_BLOCK_SIZE); 358d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt 368d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt blocks = data_len / AES_BLOCK_SIZE; 378d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt for (i = 0; i < blocks; i++) { 388d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt for (j = 0; j < AES_BLOCK_SIZE; j++) 398d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt cbc[j] ^= pos[j]; 408d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt aes_encrypt(ctx, cbc, cbc); 418d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt os_memcpy(pos, cbc, AES_BLOCK_SIZE); 428d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt pos += AES_BLOCK_SIZE; 438d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt } 448d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt aes_encrypt_deinit(ctx); 458d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt return 0; 468d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt} 478d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt 488d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt 498d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt/** 508d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt * aes_128_cbc_decrypt - AES-128 CBC decryption 518d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt * @key: Decryption key 528d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt * @iv: Decryption IV for CBC mode (16 bytes) 538d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt * @data: Data to decrypt in-place 548d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt * @data_len: Length of data in bytes (must be divisible by 16) 558d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt * Returns: 0 on success, -1 on failure 568d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt */ 578d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidtint aes_128_cbc_decrypt(const u8 *key, const u8 *iv, u8 *data, size_t data_len) 588d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt{ 598d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt void *ctx; 608d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt u8 cbc[AES_BLOCK_SIZE], tmp[AES_BLOCK_SIZE]; 618d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt u8 *pos = data; 628d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt int i, j, blocks; 638d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt 648d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt ctx = aes_decrypt_init(key, 16); 658d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt if (ctx == NULL) 668d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt return -1; 678d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt os_memcpy(cbc, iv, AES_BLOCK_SIZE); 688d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt 698d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt blocks = data_len / AES_BLOCK_SIZE; 708d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt for (i = 0; i < blocks; i++) { 718d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt os_memcpy(tmp, pos, AES_BLOCK_SIZE); 728d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt aes_decrypt(ctx, pos, pos); 738d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt for (j = 0; j < AES_BLOCK_SIZE; j++) 748d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt pos[j] ^= cbc[j]; 758d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt os_memcpy(cbc, tmp, AES_BLOCK_SIZE); 768d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt pos += AES_BLOCK_SIZE; 778d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt } 788d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt aes_decrypt_deinit(ctx); 798d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt return 0; 808d520ff1dc2da35cdca849e982051b86468016d8Dmitry Shmidt} 81