tinc/src/openssl/ecdsa.c

130 lines
3.4 KiB
C

/*
ecdsa.c -- ECDSA key handling
Copyright (C) 2011 Guus Sliepen <guus@tinc-vpn.org>
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
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.
*/
#include "system.h"
#include <openssl/pem.h>
#include <openssl/err.h>
#include "logger.h"
#include "ecdsa.h"
#include "utils.h"
// Get and set ECDSA keys
//
bool ecdsa_set_base64_public_key(ecdsa_t *ecdsa, const char *p) {
*ecdsa = EC_KEY_new_by_curve_name(NID_secp521r1);
if(!*ecdsa) {
logger(DEBUG_ALWAYS, LOG_DEBUG, "EC_KEY_new_by_curve_name failed: %s", ERR_error_string(ERR_get_error(), NULL));
return false;
}
int len = strlen(p);
unsigned char pubkey[len / 4 * 3 + 3];
const unsigned char *ppubkey = pubkey;
len = b64decode(p, (char *)pubkey, len);
if(!o2i_ECPublicKey(ecdsa, &ppubkey, len)) {
logger(DEBUG_ALWAYS, LOG_DEBUG, "o2i_ECPublicKey failed: %s", ERR_error_string(ERR_get_error(), NULL));
return false;
}
return true;
}
char *ecdsa_get_base64_public_key(ecdsa_t *ecdsa) {
unsigned char *pubkey = NULL;
int len = i2o_ECPublicKey(*ecdsa, &pubkey);
char *base64 = malloc(len * 4 / 3 + 5);
b64encode((char *)pubkey, base64, len);
free(pubkey);
return base64;
}
// Read PEM ECDSA keys
bool ecdsa_read_pem_public_key(ecdsa_t *ecdsa, FILE *fp) {
*ecdsa = PEM_read_EC_PUBKEY(fp, ecdsa, NULL, NULL);
if(*ecdsa)
return true;
logger(DEBUG_ALWAYS, LOG_ERR, "Unable to read ECDSA public key: %s", ERR_error_string(ERR_get_error(), NULL));
return false;
}
bool ecdsa_read_pem_private_key(ecdsa_t *ecdsa, FILE *fp) {
*ecdsa = PEM_read_ECPrivateKey(fp, NULL, NULL, NULL);
if(*ecdsa)
return true;
logger(DEBUG_ALWAYS, LOG_ERR, "Unable to read ECDSA private key: %s", ERR_error_string(ERR_get_error(), NULL));
return false;
}
size_t ecdsa_size(ecdsa_t *ecdsa) {
return ECDSA_size(*ecdsa);
}
// TODO: standardise output format?
bool ecdsa_sign(ecdsa_t *ecdsa, const void *in, size_t len, void *sig) {
unsigned int siglen = ECDSA_size(*ecdsa);
unsigned char hash[SHA512_DIGEST_LENGTH];
SHA512(in, len, hash);
memset(sig, 0, siglen);
if(!ECDSA_sign(0, hash, sizeof hash, sig, &siglen, *ecdsa)) {
logger(DEBUG_ALWAYS, LOG_DEBUG, "ECDSA_sign() failed: %s", ERR_error_string(ERR_get_error(), NULL));
return false;
}
return true;
}
bool ecdsa_verify(ecdsa_t *ecdsa, const void *in, size_t len, const void *sig) {
unsigned int siglen = ECDSA_size(*ecdsa);
unsigned char hash[SHA512_DIGEST_LENGTH];
SHA512(in, len, hash);
if(!ECDSA_verify(0, hash, sizeof hash, sig, siglen, *ecdsa)) {
logger(DEBUG_ALWAYS, LOG_DEBUG, "ECDSA_verify() failed: %s", ERR_error_string(ERR_get_error(), NULL));
return false;
}
return true;
}
bool ecdsa_active(ecdsa_t *ecdsa) {
return *ecdsa;
}
void ecdsa_free(ecdsa_t *ecdsa) {
if(*ecdsa) {
EC_KEY_free(*ecdsa);
*ecdsa = NULL;
}
}