| /* |
| chronyd/chronyc - Programs for keeping computer clocks accurate. |
| |
| ********************************************************************** |
| * Copyright (C) Miroslav Lichvar 2019 |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of version 2 of the GNU General Public License as |
| * published by the Free Software Foundation. |
| * |
| * This program is distributed in the hope that it will be useful, but |
| * WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License along |
| * with this program; if not, write to the Free Software Foundation, Inc., |
| * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. |
| * |
| ********************************************************************** |
| |
| ======================================================================= |
| |
| Support for AES128 and AES256 CMAC in Nettle. |
| |
| */ |
| |
| #include "config.h" |
| |
| #include "sysincl.h" |
| |
| #include <nettle/cmac.h> |
| |
| #include "cmac.h" |
| #include "memory.h" |
| |
| struct CMC_Instance_Record { |
| int key_length; |
| union { |
| struct cmac_aes128_ctx aes128; |
| struct cmac_aes256_ctx aes256; |
| } context; |
| }; |
| |
| /* ================================================== */ |
| |
| int |
| CMC_GetKeyLength(CMC_Algorithm algorithm) |
| { |
| if (algorithm == CMC_AES128) |
| return AES128_KEY_SIZE; |
| else if (algorithm == CMC_AES256) |
| return AES256_KEY_SIZE; |
| return 0; |
| } |
| |
| /* ================================================== */ |
| |
| CMC_Instance |
| CMC_CreateInstance(CMC_Algorithm algorithm, const unsigned char *key, int length) |
| { |
| CMC_Instance inst; |
| |
| if (length <= 0 || length != CMC_GetKeyLength(algorithm)) |
| return NULL; |
| |
| inst = MallocNew(struct CMC_Instance_Record); |
| inst->key_length = length; |
| |
| switch (length) { |
| case AES128_KEY_SIZE: |
| cmac_aes128_set_key(&inst->context.aes128, key); |
| break; |
| case AES256_KEY_SIZE: |
| cmac_aes256_set_key(&inst->context.aes256, key); |
| break; |
| default: |
| assert(0); |
| } |
| |
| return inst; |
| } |
| |
| /* ================================================== */ |
| |
| int |
| CMC_Hash(CMC_Instance inst, const void *in, int in_len, unsigned char *out, int out_len) |
| { |
| if (in_len < 0 || out_len < 0) |
| return 0; |
| |
| if (out_len > CMAC128_DIGEST_SIZE) |
| out_len = CMAC128_DIGEST_SIZE; |
| |
| switch (inst->key_length) { |
| case AES128_KEY_SIZE: |
| cmac_aes128_update(&inst->context.aes128, in_len, in); |
| cmac_aes128_digest(&inst->context.aes128, out_len, out); |
| break; |
| case AES256_KEY_SIZE: |
| cmac_aes256_update(&inst->context.aes256, in_len, in); |
| cmac_aes256_digest(&inst->context.aes256, out_len, out); |
| break; |
| default: |
| assert(0); |
| } |
| |
| return out_len; |
| } |
| |
| /* ================================================== */ |
| |
| void |
| CMC_DestroyInstance(CMC_Instance inst) |
| { |
| Free(inst); |
| } |