-/*
- ecdsa.c -- ECDSA key handling
- Copyright (C) 2011-2013 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>
-
-#define __TINC_ECDSA_INTERNAL__
-typedef EC_KEY ecdsa_t;
-
-#include "../logger.h"
-#include "../ecdsa.h"
-#include "../utils.h"
-#include "../xalloc.h"
-
-// Get and set ECDSA keys
-//
-ecdsa_t *ecdsa_set_base64_public_key(const char *p) {
- ecdsa_t *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 NULL;
- }
-
- 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));
- EC_KEY_free(ecdsa);
- return NULL;
- }
-
- return ecdsa;
-}
-
-char *ecdsa_get_base64_public_key(ecdsa_t *ecdsa) {
- unsigned char *pubkey = NULL;
- int len = i2o_ECPublicKey(ecdsa, &pubkey);
-
- char *base64 = xmalloc(len * 4 / 3 + 5);
- b64encode((char *)pubkey, base64, len);
-
- free(pubkey);
-
- return base64;
-}
-
-// Read PEM ECDSA keys
-
-ecdsa_t *ecdsa_read_pem_public_key(FILE *fp) {
- ecdsa_t *ecdsa = PEM_read_EC_PUBKEY(fp, NULL, NULL, NULL);
-
- if(!ecdsa)
- logger(DEBUG_ALWAYS, LOG_ERR, "Unable to read ECDSA public key: %s", ERR_error_string(ERR_get_error(), NULL));
-
- return ecdsa;
-}
-
-ecdsa_t *ecdsa_read_pem_private_key(FILE *fp) {
- ecdsa_t *ecdsa = PEM_read_ECPrivateKey(fp, NULL, NULL, NULL);
-
- if(!ecdsa)
- logger(DEBUG_ALWAYS, LOG_ERR, "Unable to read ECDSA private key: %s", ERR_error_string(ERR_get_error(), NULL));
-
- return ecdsa;
-}
-
-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);
-}