2 digest.c -- Digest handling
3 Copyright (C) 2007 Guus Sliepen <guus@tinc-vpn.org>
5 This program is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 2 of the License, or
8 (at your option) any later version.
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with this program; if not, write to the Free Software
17 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
24 #include <openssl/err.h>
29 static void set_maclength(digest_t *digest, int maclength) {
30 int digestlen = EVP_MD_size(digest->digest);
32 if(maclength > digestlen || maclength < 0)
33 digest->maclength = digestlen;
35 digest->maclength = maclength;
38 bool digest_open_by_name(digest_t *digest, const char *name, int maclength) {
39 digest->digest = EVP_get_digestbyname(name);
42 logger(LOG_DEBUG, "Unknown digest name '%s'!", name);
46 set_maclength(digest, maclength);
50 bool digest_open_by_nid(digest_t *digest, int nid, int maclength) {
51 digest->digest = EVP_get_digestbynid(nid);
54 logger(LOG_DEBUG, "Unknown digest nid %d!", nid);
58 set_maclength(digest, maclength);
62 bool digest_open_sha1(digest_t *digest, int maclength) {
63 digest->digest = EVP_sha1();
65 set_maclength(digest, maclength);
69 void digest_close(digest_t *digest) {
72 bool digest_create(digest_t *digest, const void *indata, size_t inlen, void *outdata) {
73 size_t len = EVP_MD_size(digest->digest);
74 unsigned char tmpdata[len];
78 if(!EVP_DigestInit(&ctx, digest->digest)
79 || !EVP_DigestUpdate(&ctx, indata, inlen)
80 || !EVP_DigestFinal(&ctx, tmpdata, NULL)) {
81 logger(LOG_DEBUG, "Error creating digest: %s", ERR_error_string(ERR_get_error(), NULL));
85 memcpy(outdata, tmpdata, digest->maclength);
89 bool digest_verify(digest_t *digest, const void *indata, size_t inlen, const void *cmpdata) {
90 size_t len = EVP_MD_size(digest->digest);
91 unsigned char outdata[len];
93 return digest_create(digest, indata, inlen, outdata) && !memcmp(cmpdata, outdata, digest->maclength);
96 int digest_get_nid(const digest_t *digest) {
97 return digest->digest ? digest->digest->type : 0;
100 size_t digest_length(const digest_t *digest) {
101 return digest->maclength;
104 bool digest_active(const digest_t *digest) {
105 return digest->digest && digest->digest->type != 0;