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 along
16 with this program; if not, write to the Free Software Foundation, Inc.,
17 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
24 #include <openssl/err.h>
25 #include <openssl/hmac.h>
30 static void set_maclength(digest_t *digest, int maclength) {
31 int digestlen = EVP_MD_size(digest->digest);
33 if(maclength > digestlen || maclength < 0)
34 digest->maclength = digestlen;
36 digest->maclength = maclength;
39 bool digest_open_by_name(digest_t *digest, const char *name, int maclength) {
40 digest->digest = EVP_get_digestbyname(name);
44 logger(LOG_DEBUG, "Unknown digest name '%s'!", name);
48 set_maclength(digest, maclength);
52 bool digest_open_by_nid(digest_t *digest, int nid, int maclength) {
53 digest->digest = EVP_get_digestbynid(nid);
57 logger(LOG_DEBUG, "Unknown digest nid %d!", nid);
61 set_maclength(digest, maclength);
65 bool digest_open_sha1(digest_t *digest, int maclength) {
66 digest->digest = EVP_sha1();
69 set_maclength(digest, maclength);
73 bool digest_set_key(digest_t *digest, const void *key, size_t len) {
74 digest->key = xrealloc(digest->key, len);
75 memcpy(digest->key, key, len);
76 digest->keylength = len;
80 void digest_close(digest_t *digest) {
86 bool digest_create(digest_t *digest, const void *indata, size_t inlen, void *outdata) {
87 size_t len = EVP_MD_size(digest->digest);
88 unsigned char tmpdata[len];
91 HMAC(digest->digest, digest->key, digest->keylength, indata, inlen, tmpdata, NULL);
95 if(!EVP_DigestInit(&ctx, digest->digest)
96 || !EVP_DigestUpdate(&ctx, indata, inlen)
97 || !EVP_DigestFinal(&ctx, tmpdata, NULL)) {
98 logger(LOG_DEBUG, "Error creating digest: %s", ERR_error_string(ERR_get_error(), NULL));
103 memcpy(outdata, tmpdata, digest->maclength);
107 bool digest_verify(digest_t *digest, const void *indata, size_t inlen, const void *cmpdata) {
108 size_t len = digest->maclength;
109 unsigned char outdata[len];
111 return digest_create(digest, indata, inlen, outdata) && !memcmp(cmpdata, outdata, digest->maclength);
114 int digest_get_nid(const digest_t *digest) {
115 return digest->digest ? digest->digest->type : 0;
118 size_t digest_keylength(const digest_t *digest) {
119 return digest->digest->md_size;
122 size_t digest_length(const digest_t *digest) {
123 return digest->maclength;
126 bool digest_active(const digest_t *digest) {
127 return digest->digest && digest->digest->type != 0;