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/*
* Copyright 2014-2022 The GmSSL Project. All Rights Reserved.
*
* Licensed under the Apache License, Version 2.0 (the License); you may
* not use this file except in compliance with the License.
*
* http://www.apache.org/licenses/LICENSE-2.0
*/
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <gmssl/rand.h>
#include <gmssl/error.h>
#define RAND_MAX_BUF_SIZE 4096
int rand_bytes(uint8_t *buf, size_t len)
{
FILE *fp;
if (!buf) {
error_print();
return -1;
}
if (len > RAND_MAX_BUF_SIZE) {
error_print();
return -1;
}
if (!len) {
return 0;
}
if (!(fp = fopen("/dev/urandom", "rb"))) {
error_print();
return -1;
}
if (fread(buf, 1, len, fp) != len) {
error_print();
fclose(fp);
return -1;
}
fclose(fp);
return 1;
}