/*====================================================================*
 *
 *   Copyright (c) 2013 Qualcomm Atheros, Inc.
 *
 *   All rights reserved.
 *
 *   Redistribution and use in source and binary forms, with or
 *   without modification, are permitted (subject to the limitations
 *   in the disclaimer below) provided that the following conditions
 *   are met:
 *
 *   * Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *
 *   * Redistributions in binary form must reproduce the above
 *     copyright notice, this list of conditions and the following
 *     disclaimer in the documentation and/or other materials
 *     provided with the distribution.
 *
 *   * Neither the name of Qualcomm Atheros nor the names of
 *     its contributors may be used to endorse or promote products
 *     derived from this software without specific prior written
 *     permission.
 *
 *   NO EXPRESS OR IMPLIED LICENSES TO ANY PARTY'S PATENT RIGHTS ARE
 *   GRANTED BY THIS LICENSE. THIS SOFTWARE IS PROVIDED BY THE
 *   COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR
 *   IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 *   WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 *   PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
 *   OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 *   NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 *   LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 *   HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 *   CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
 *   OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 *   SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 *--------------------------------------------------------------------*/

/*====================================================================*
 *
 *   rkey.c - random key generator;
 *
 *   generate random SHA256, device access, network membership and
 *   network identifier keys using a seed file;
 *
 *   read the seed file, increment the seed for each key generated
 *   then save the seed when done; exit the loop in an orderly way
 *   on keyboard interrupt;
 *
 *
 *   Contributor(s);
 *	Charles Maier
 *
 *--------------------------------------------------------------------*/

#define _GETOPT_H

/*====================================================================*
 *   system header files;
 *--------------------------------------------------------------------*/

#include <unistd.h>
#include <stdlib.h>
#include <limits.h>
#include <signal.h>
#include <errno.h>

/*====================================================================*
 *   custom header files;
 *--------------------------------------------------------------------*/

#include "../tools/getoptv.h"
#include "../tools/putoptv.h"
#include "../tools/memory.h"
#include "../tools/number.h"
#include "../tools/error.h"
#include "../tools/files.h"
#include "../tools/flags.h"
#include "../key/HPAVKey.h"
#include "../key/SHA256.h"

/*====================================================================*
 *   custom source files;
 *--------------------------------------------------------------------*/

#ifndef MAKEFILE
#include "../tools/getoptv.c"
#include "../tools/putoptv.c"
#include "../tools/version.c"
#include "../tools/uintspec.c"
#include "../tools/todigit.c"
#include "../tools/strincr.c"
#include "../tools/hexout.c"
#include "../tools/error.c"
#endif

#ifndef MAKEFILE
#include "../key/HPAVKeyDAK.c"
#include "../key/HPAVKeyNMK.c"
#include "../key/HPAVKeyNID.c"
#include "../key/HPAVKeySHA.c"
#include "../key/HPAVKeyOut.c"
#include "../key/SHA256Reset.c"
#include "../key/SHA256Write.c"
#include "../key/SHA256Block.c"
#include "../key/SHA256Fetch.c"
#endif

/*====================================================================*
 *   program constants;
 *--------------------------------------------------------------------*/

#define DEFAULT_LEVEL 0
#define DEFAULT_COUNT 1

/*====================================================================*
 *   program variables;
 *--------------------------------------------------------------------*/

static unsigned count = DEFAULT_COUNT;

/*====================================================================*
 *
 *   void stop (signo_t signal);
 *
 *   terminate the program; we want to ensure an organized program
 *   exit such that the current pass phrase is saved;
 *
 *
 *--------------------------------------------------------------------*/

#if defined (__linux__)

static void stop (signo_t signal)

{
	count = 0;
	return;
}


#endif

/*====================================================================*
 *
 *   int main (int argc, const char * argv []);
 *
 *
 *
 *--------------------------------------------------------------------*/

int main (int argc, const char * argv [])

{
	static const char * optv [] =
	{
		"DL:MNn:oqv",
		"seedfile",
		"generate HomePlug AV compliant keys",
		"D\tDAK - Device Access Keys",
		"L n\tSecurity Level is n [" LITERAL (DEFAULT_LEVEL) "]",
		"M\tNMK - Network Membership Keys",
		"N\tNID - Network Identifier",
		"n n\tgenerate n keys [" LITERAL (DEFAULT_COUNT) "]",
		"o\tuse old seedfile value",
		"q\tquiet mode",
		"v\tverbose mode",
		(const char *)(0)
	};

#if defined (__linux__)

	struct sigaction sa;

#endif

	char phrase [HPAVKEY_PHRASE_MAX + 1];
	uint8_t digest [SHA256_DIGEST_LENGTH];
	unsigned level = DEFAULT_LEVEL;
	signed type = 0;
	signed next = 1;
	signed fd;
	flag_t flags = (flag_t)(0);
	signed c;
	while ((c = getoptv (argc, argv, optv)) != -1)
	{
		switch ((char)(c))
		{
		case 'D':
			type = HPAVKEY_DAK;
			break;
		case 'M':
			type = HPAVKEY_NMK;
			break;
		case 'N':
			type = HPAVKEY_NID;
			break;
		case 'n':
			count = (unsigned)(uintspec (optarg, 0, UINT_MAX));
			break;
		case 'L':
			level = (unsigned)(uintspec (optarg, 0, 1));
			break;
		case 'o':
			next = 0;
			break;
		case 'q':
			_setbits (flags, HPAVKEY_SILENCE);
			break;
		case 'v':
			_setbits (flags, HPAVKEY_VERBOSE);
			break;
		default:
			break;
		}
	}
	argc -= optind;
	argv += optind;
	if (argc != 1)
	{
		error (1, ECANCELED, "No secret file given");
	}
	memset (phrase, 0, sizeof (phrase));
	if ((fd = open (* argv, O_BINARY|O_CREAT|O_RDWR, FILE_FILEMODE)) == -1)
	{
		error (1, errno, "Can't open %s", * argv);
	}
	if (read (fd, phrase, sizeof (phrase) - 1) == -1)
	{
		error (1, errno, "Can't read seedfile");
	}
	for (c = 0; c < (signed)(sizeof (phrase) - 1); c++)
	{
		if (phrase [c] < HPAVKEY_CHAR_MIN)
		{
			phrase [c] = HPAVKEY_CHAR_MIN;
			continue;
		}
		if (phrase [c] > HPAVKEY_CHAR_MAX)
		{
			phrase [c] = HPAVKEY_CHAR_MAX;
			continue;
		}
	}

#if defined (__linux__)

	memset (&sa, 0, sizeof (struct sigaction));
	sa.sa_handler = stop;
	sigaction (SIGTERM, &sa, (struct sigaction *)(0));
	sigaction (SIGQUIT, &sa, (struct sigaction *)(0));
	sigaction (SIGTSTP, &sa, (struct sigaction *)(0));
	sigaction (SIGINT, &sa, (struct sigaction *)(0));
	sigaction (SIGHUP, &sa, (struct sigaction *)(0));

#endif

	while (count-- > 0)
	{
		memset (digest, 0, sizeof (digest));
		if (next && strincr ((uint8_t *)(phrase), (size_t) (sizeof (phrase) - 1), HPAVKEY_CHAR_MIN, HPAVKEY_CHAR_MAX))
		{
			error (1, errno, "Can't increment seedfile");
		}
		if (type == HPAVKEY_DAK)
		{
			HPAVKeyDAK (digest, phrase);
			HPAVKeyOut (digest, HPAVKEY_DAK_LEN, phrase, flags);
			continue;
		}
		if (type == HPAVKEY_NMK)
		{
			HPAVKeyNMK (digest, phrase);
			HPAVKeyOut (digest, HPAVKEY_NMK_LEN, phrase, flags);
			continue;
		}
		if (type == HPAVKEY_NID)
		{
			HPAVKeyNMK (digest, phrase);
			HPAVKeyNID (digest, digest, level);
			HPAVKeyOut (digest, HPAVKEY_NID_LEN, phrase, flags);
			continue;
		}
		HPAVKeySHA (digest, phrase);
		HPAVKeyOut (digest, HPAVKEY_SHA_LEN, phrase, flags);
	}
	if (lseek (fd, 0, SEEK_SET) == -1)
	{
		error (1, errno, "Can't rewind seedfile");
	}
	if (write (fd, phrase, sizeof (phrase) - 1) == -1)
	{
		error (1, errno, "Can't update seedfile");
	}
	close (fd);
	return (0);
}