masqmail

annotate src/md5/hmac_md5.c @ 421:f37384470855

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Changed lockdir to /var/lock/masqmail; Create lockdir and piddir on startup. Moved the lockdir out of the spool dir. (When /var/lock is a ramdisk we do well to have the lock files there.) Added the new configure option --with-lockdir to change that location. Nontheless, if we run_as_user, then lock files are always stored in the spool dir directly. Instead of installing the lockdir and piddir at installation time, we create them on startup time now if they are missing. This is necessary if lockdir or piddir are a tmpfs.
author markus schnalke <meillo@marmaro.de>
date Wed, 30 May 2012 09:38:38 +0200
parents 41958685480d
children
rev   line source
meillo@0 1 /*
meillo@367 2 ** hmac_md5 -- implements RFC 2104
meillo@367 3 **
meillo@367 4 ** Copyright 2010, markus schnalke <meillo@marmaro.de>
meillo@367 5 **
meillo@367 6 ** Permission to use, copy, modify, and/or distribute this software for any
meillo@367 7 ** purpose with or without fee is hereby granted, provided that the above
meillo@367 8 ** copyright notice and this permission notice appear in all copies.
meillo@367 9 **
meillo@367 10 ** THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
meillo@367 11 ** WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
meillo@367 12 ** MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
meillo@367 13 ** ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
meillo@367 14 ** WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
meillo@367 15 ** ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
meillo@367 16 ** OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
meillo@367 17 **
meillo@367 18 **
meillo@367 19 ** My motivation to write this code was the lack of a nicely licensed
meillo@367 20 ** hmac_md5 function in C. I programmed it following the RFC's text.
meillo@367 21 ** Obviously this code is highly similar to the sample code of the RFC.
meillo@367 22 ** The code is tested against the test vectors of the RFC. Wikipedia's
meillo@367 23 ** HMAC page helped me to understand the algorithm better.
meillo@367 24 **
meillo@367 25 ** This hmac_md5 function requires an OpenSSL-compatible MD5
meillo@367 26 ** implementation. There are Public Domain MD5 implementations by Colin
meillo@367 27 ** Plumb and by Solar Designer. You probably want to use one of these.
meillo@0 28 */
meillo@0 29
meillo@0 30 #include <string.h>
meillo@0 31 #include "md5.h"
meillo@0 32
meillo@211 33
meillo@211 34 const int blocksize = 64;
meillo@211 35 const int hashsize = 16;
meillo@211 36
meillo@211 37
meillo@211 38 /*
meillo@367 39 ** The computed HMAC will be written to `digest'.
meillo@367 40 ** Ensure digest points to hashsize bytes of allocated memory.
meillo@211 41 */
meillo@10 42 void
meillo@367 43 hmac_md5(unsigned char *text, int textlen, unsigned char *key, int keylen,
meillo@367 44 unsigned char *digest)
meillo@10 45 {
meillo@211 46 int i;
meillo@10 47 MD5_CTX context;
meillo@211 48 unsigned char ipad[blocksize];
meillo@211 49 unsigned char opad[blocksize];
meillo@0 50
meillo@211 51 /* too long keys are replaced by their hash value */
meillo@211 52 if (keylen > blocksize) {
meillo@211 53 MD5_Init(&context);
meillo@211 54 MD5_Update(&context, key, keylen);
meillo@211 55 MD5_Final(digest, &context);
meillo@211 56 key = digest;
meillo@211 57 keylen = hashsize;
meillo@10 58 }
meillo@0 59
meillo@211 60 /* copy the key into the pads */
meillo@211 61 memset(ipad, 0, sizeof(ipad));
meillo@211 62 memcpy(ipad, key, keylen);
meillo@0 63
meillo@211 64 memset(opad, 0, sizeof(opad));
meillo@211 65 memcpy(opad, key, keylen);
meillo@0 66
meillo@211 67 /* xor the pads with their ``basic'' value */
meillo@211 68 for (i=0; i<blocksize; i++) {
meillo@211 69 ipad[i] ^= 0x36;
meillo@211 70 opad[i] ^= 0x5c;
meillo@10 71 }
meillo@211 72
meillo@211 73 /* inner pass (ipad ++ message) */
meillo@211 74 MD5_Init(&context);
meillo@211 75 MD5_Update(&context, ipad, sizeof(ipad));
meillo@211 76 MD5_Update(&context, text, textlen);
meillo@211 77 MD5_Final(digest, &context);
meillo@211 78
meillo@211 79 /* outer pass (opad ++ result of inner pass) */
meillo@211 80 MD5_Init(&context);
meillo@211 81 MD5_Update(&context, opad, sizeof(opad));
meillo@211 82 MD5_Update(&context, digest, hashsize);
meillo@211 83 MD5_Final(digest, &context);
meillo@0 84 }