actube/src/capwap/cw_rand.c
7u83@mail.ru 76e044c1fb WTP sends session id.
FossilOrigin-Name: 32e0df82a8e40e3a3953127ceae58359cdce56696d802e54983f813b00ed1342
2015-04-10 19:44:05 +00:00

82 lines
1.7 KiB
C

/*
This file is part of libcapwap.
libcapwap 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 3 of the License, or
(at your option) any later version.
libcapwap 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 Foobar. If not, see <http://www.gnu.org/licenses/>.
*/
#include <stdlib.h>
#include <stdint.h>
#include <stdio.h>
#include <string.h>
#include <errno.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include "cw_util.h"
#include "log.h"
char *cw_rand_dev = "/dev/random";
int cw_rand_r(uint8_t * dst, int len)
{
int rf;
int l;
rf = open(cw_rand_dev, O_RDONLY | O_NDELAY);
if (rf < 0) {
cw_log(LOG_ERR, "Can't open %s: %s", cw_rand_dev, strerror(errno));
return 0;
}
l = read(rf, dst, len);
close(rf);
if ((l < 0) && (errno != EAGAIN)) {
cw_log(LOG_ERR, "Cant read from %s: %s", cw_rand_dev, strerror(errno));
return 0;
}
return l;
}
int cw_rand(uint8_t * dst, int len)
{
static uint32_t rinit = 0;
if (!rinit) {
int l = cw_rand_r((uint8_t *) (&rinit), sizeof(uint32_t));
if (l < sizeof(uint32_t)) {
cw_log(LOG_WARNING,
"Can't read enough bytes from %s. Using time to init rand instead.",
cw_rand_dev);
rinit = time(NULL);
}
srand(rinit);
}
int i;
for (i = 0; i < len; i++) {
dst[i] = rand();
}
return len;
}