/*
 * Copyright (C) 2008-2012 Free Software Foundation, Inc.
 *
 * Author: Nikos Mavrogiannopoulos
 *
 * This file is part of GnuTLS.
 *
 * GnuTLS 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.
 *
 * GnuTLS 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 GnuTLS.  If not, see <http://www.gnu.org/licenses/>.
 *
 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
#include <assert.h>
#if !defined(_WIN32)
#include <sys/wait.h>
#endif

#include "utils.h"
#include <gnutls/gnutls.h>
#include <gnutls/crypto.h>

#if !defined(_WIN32)
static void dump(const char *name, unsigned char *buf, int buf_size)
{
	int i;
	printf("%s: ", name);
	for (i = 0; i < buf_size; i++)
		printf("%.2x:", buf[i]);
	printf("\n");
}

#define FILENAME "./rng-test"

void doit(void)
{
	unsigned char buf1[64];
	unsigned char buf2[64];
	pid_t pid;
	unsigned char *tmp;
	int ret;
	FILE *fp;
	unsigned i;

	global_init();

	for (i = GNUTLS_RND_NONCE; i <= GNUTLS_RND_KEY; i++) {
		pid = fork();
		if (pid == 0) {
			fp = fopen(FILENAME, "w");
			if (fp == NULL)
				fail("cannot open file");

			assert(gnutls_rnd(i, buf1, sizeof(buf1)) >= 0);
			if (debug)
				dump("buf1", buf1, sizeof(buf1));

			fwrite(buf1, 1, sizeof(buf1), fp);
			fclose(fp);
			gnutls_global_deinit();
			exit(0);
		} else {
			/* daddy */
			assert(gnutls_rnd(i, buf2, sizeof(buf2)) >= 0);
			if (debug)
				dump("buf2", buf2, sizeof(buf2));
			waitpid(pid, NULL, 0);

			fp = fopen(FILENAME, "r");
			if (fp == NULL)
				fail("cannot open file");

			ret = fread(buf1, 1, sizeof(buf1), fp);

			fclose(fp);
			remove(FILENAME);

			if (ret != sizeof(buf1)) {
				fail("error testing the random generator (%u).\n", i);
				return;
			}

			if (memcmp(buf1, buf2, sizeof(buf1)) == 0) {
				fail("error in the random generator (%u). Produces same valus after fork()\n", i);
				return;
			}
			if (debug)
				success("success\n");
		}
	}

	for (i = 0; i <= 65539; i++) {
		ret = gnutls_rnd(GNUTLS_RND_NONCE, buf1, sizeof(buf1));
		if (ret < 0) {
			fail("Error iterating RNG-nonce more than %u times\n", i);
			exit(1);
		}
	}

	for (i = 0; i <= 65539; i++) {
		ret = gnutls_rnd(GNUTLS_RND_RANDOM, buf1, sizeof(buf1));
		if (ret < 0) {
			fail("Error iterating RNG-random more than %u times\n", i);
			exit(1);
		}
	}
#define TMP_SIZE (65*1024)
	tmp = malloc(TMP_SIZE);
	if (tmp == NULL) {
		fail("memory error\n");
		exit(1);
	}
	for (i = 0; i <= 65539; i++) {
		ret = gnutls_rnd(GNUTLS_RND_RANDOM, tmp, TMP_SIZE);
		if (ret < 0) {
			fail("Error iterating RNG-random more than %u times for %d data\n", i, TMP_SIZE);
			exit(1);
		}
	}
	free(tmp);

	gnutls_global_deinit();
}
#else
void doit(void)
{
	exit(77);
}
#endif