1 /* hmac-md5.c -- hashed message authentication codes
2 Copyright (C) 2005 Free Software Foundation, Inc.
4 This program is free software; you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation; either version 2, or (at your option)
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
14 You should have received a copy of the GNU General Public License
15 along with this program; if not, write to the Free Software Foundation,
16 Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
18 /* Written by Simon Josefsson. */
34 hmac_md5 (const void *key, size_t keylen,
35 const void *in, size_t inlen, void *resbuf)
45 struct md5_ctx keyhash;
47 md5_init_ctx (&keyhash);
48 md5_process_bytes (key, keylen, &keyhash);
49 md5_finish_ctx (&keyhash, optkeybuf);
55 md5_init_ctx (&inner);
57 memset (block, IPAD, sizeof (block));
58 memxor (block, key, keylen);
60 md5_process_block (block, 64, &inner);
61 md5_process_bytes (in, inlen, &inner);
63 md5_finish_ctx (&inner, innerhash);
65 md5_init_ctx (&outer);
67 memset (block, OPAD, sizeof (block));
68 memxor (block, key, keylen);
70 md5_process_block (block, 64, &outer);
71 md5_process_bytes (innerhash, 16, &outer);
73 md5_finish_ctx (&outer, resbuf);