tinc/src/openssl/crypto.c
2019-08-26 13:44:51 +02:00

105 lines
2.4 KiB
C

/*
crypto.c -- Cryptographic miscellaneous functions and initialisation
Copyright (C) 2007-2014 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/rand.h>
#include <openssl/evp.h>
#include <openssl/engine.h>
#include "../crypto.h"
#ifndef HAVE_MINGW
static int random_fd = -1;
static void random_init(void) {
random_fd = open("/dev/urandom", O_RDONLY);
if(random_fd < 0)
random_fd = open("/dev/random", O_RDONLY);
if(random_fd < 0) {
fprintf(stderr, "Could not open source of random numbers: %s\n", strerror(errno));
abort();
}
}
static void random_exit(void) {
close(random_fd);
}
void randomize(void *out, size_t outlen) {
while(outlen) {
size_t len = read(random_fd, out, outlen);
if(len <= 0) {
if(errno == EAGAIN || errno == EINTR)
continue;
fprintf(stderr, "Could not read random numbers: %s\n", strerror(errno));
abort();
}
out += len;
outlen -= len;
}
}
#else
#include <wincrypt.h>
HCRYPTPROV prov;
void random_init(void) {
if(!CryptAcquireContext(&prov, NULL, NULL, PROV_RSA_FULL, CRYPT_VERIFYCONTEXT)) {
fprintf(stderr, "CryptAcquireContext() failed!\n");
abort();
}
}
void random_exit(void) {
CryptReleaseContext(prov, 0);
}
void randomize(void *out, size_t outlen) {
if(!CryptGenRandom(prov, outlen, out)) {
fprintf(stderr, "CryptGenRandom() failed\n");
abort();
}
}
#endif
void crypto_init(void) {
random_init();
ENGINE_load_builtin_engines();
ENGINE_register_all_complete();
ERR_load_crypto_strings();
OpenSSL_add_all_algorithms();
if(!RAND_status()) {
fprintf(stderr, "Not enough entropy for the PRNG!\n");
abort();
}
}
void crypto_exit(void) {
EVP_cleanup();
ERR_free_strings();
ENGINE_cleanup();
random_exit();
}