2 crypto.c -- Cryptographic miscellaneous functions and initialisation
3 Copyright (C) 2014 Guus Sliepen <guus@meshlink.io>
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 //TODO: use a strict random source once to seed a PRNG?
28 static int random_fd = -1;
30 void crypto_init(void) {
31 random_fd = open("/dev/urandom", O_RDONLY);
34 random_fd = open("/dev/random", O_RDONLY);
38 fprintf(stderr, "Could not open source of random numbers: %s\n", strerror(errno));
43 void crypto_exit(void) {
47 void randomize(void *out, size_t outlen) {
51 size_t len = read(random_fd, ptr, outlen);
54 if(errno == EAGAIN || errno == EINTR) {
58 fprintf(stderr, "Could not read random numbers: %s\n", strerror(errno));
72 void crypto_init(void) {
73 if(!CryptAcquireContext(&prov, NULL, NULL, PROV_RSA_FULL, CRYPT_VERIFYCONTEXT)) {
74 fprintf(stderr, "CryptAcquireContext() failed!\n");
79 void crypto_exit(void) {
80 CryptReleaseContext(prov, 0);
83 void randomize(void *out, size_t outlen) {
84 if(!CryptGenRandom(prov, outlen, out)) {
85 fprintf(stderr, "CryptGenRandom() failed\n");