paulo@0: /*
paulo@0:  * $Id: gt_guid.c,v 1.18 2006/01/28 16:57:56 mkern Exp $
paulo@0:  *
paulo@0:  * Copyright (C) 2001-2003 giFT project (gift.sourceforge.net)
paulo@0:  *
paulo@0:  * This program is free software; you can redistribute it and/or modify it
paulo@0:  * under the terms of the GNU General Public License as published by the
paulo@0:  * Free Software Foundation; either version 2, or (at your option) any
paulo@0:  * later version.
paulo@0:  *
paulo@0:  * This program is distributed in the hope that it will be useful, but
paulo@0:  * WITHOUT ANY WARRANTY; without even the implied warranty of
paulo@0:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
paulo@0:  * General Public License for more details.
paulo@0:  */
paulo@0: 
paulo@0: #include "gt_gnutella.h"
paulo@0: #include "sha1.h"
paulo@0: 
paulo@0: /*****************************************************************************/
paulo@0: 
paulo@0: /* global guid identifying this client */
paulo@0: gt_guid_t *GT_SELF_GUID;
paulo@0: 
paulo@0: /*****************************************************************************/
paulo@0: 
paulo@0: /* seed for generating unique numbers */
paulo@0: static unsigned int seed = 0;
paulo@0: 
paulo@0: /* map binary numbers to hexadecimal */
paulo@0: static char bin_to_hex[] = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
paulo@0:                              'a', 'b', 'c', 'd', 'e', 'f' };
paulo@0: 
paulo@0: /* guid filled with all zeroes */
paulo@0: static gt_guid_t zero_guid[GT_GUID_LEN] = { 0 };
paulo@0: 
paulo@0: /*****************************************************************************/
paulo@0: 
paulo@0: /* TODO: use /dev/urandom when available */
paulo@0: static unsigned int rng_seed (void)
paulo@0: {
paulo@0: 	sha1_state_t   sha1;
paulo@0: 	struct timeval tv;
paulo@0: 	unsigned int   seed;
paulo@0: 	int            i;
paulo@0: 	unsigned char  hash[SHA1_BINSIZE];
paulo@0: 
paulo@0: 	gt_sha1_init (&sha1);
paulo@0: 	platform_gettimeofday (&tv, NULL);
paulo@0: 
paulo@0: 	gt_sha1_append (&sha1, &tv.tv_usec, sizeof (tv.tv_usec));
paulo@0: 	gt_sha1_append (&sha1, &tv.tv_sec, sizeof (tv.tv_sec));
paulo@0: 
paulo@0: #ifdef HAVE_GETPID
paulo@0: 	{
paulo@0: 		pid_t pid = getpid();
paulo@0: 		gt_sha1_append (&sha1, &pid, sizeof (pid));
paulo@0: 	}
paulo@0: #endif
paulo@0: 
paulo@0: #ifdef WIN32
paulo@0: 	{
paulo@0: 		DWORD process_id = GetCurrentProcessId();
paulo@0: 		gt_sha1_append (&sha1, &process_id, sizeof (process_id));
paulo@0: 	}
paulo@0: #endif
paulo@0: 
paulo@0: #ifdef HAVE_GETPPID
paulo@0: 	{
paulo@0: 		pid_t ppid = getppid();
paulo@0: 		gt_sha1_append (&sha1, &ppid, sizeof (ppid));
paulo@0: 	}
paulo@0: #endif /* WIN32 */
paulo@0: 
paulo@0: 	memset (hash, 0, sizeof (hash));
paulo@0: 	gt_sha1_finish (&sha1, hash);
paulo@0: 
paulo@0: 	seed = 0;
paulo@0: 	i    = 0;
paulo@0: 
paulo@0: 	/* crush the hash into an unsigned int */
paulo@0: 	while (i < SHA1_BINSIZE)
paulo@0: 	{
paulo@0: 		unsigned int t;
paulo@0: 		size_t       len;
paulo@0: 
paulo@0: 		t = 0;
paulo@0: 		len = MIN (sizeof (unsigned int), SHA1_BINSIZE - i);
paulo@0: 
paulo@0: 		memcpy (&t, &hash[i], len);
paulo@0: 
paulo@0: 		seed ^= t;
paulo@0: 		i += len;
paulo@0: 	}
paulo@0: 
paulo@0: 	return seed;
paulo@0: }
paulo@0: 
paulo@0: void gt_guid_init (gt_guid_t *guid)
paulo@0: {
paulo@0: 	int i;
paulo@0: 
paulo@0: 	if (!seed)
paulo@0: 	{
paulo@0: 		seed = rng_seed();
paulo@0: 		srand (seed);
paulo@0: 	}
paulo@0: 
paulo@0: 	for (i = GT_GUID_LEN - 1; i >= 0; i--)
paulo@0: 		guid[i] = 256.0 * rand() / (RAND_MAX + 1.0);
paulo@0: 
paulo@0: 	/* mark this GUID as coming from a "new" client */
paulo@0: 	guid[8]  = 0xff;
paulo@0: 	guid[15] = 0x01;
paulo@0: }
paulo@0: 
paulo@0: gt_guid_t *gt_guid_new (void)
paulo@0: {
paulo@0: 	gt_guid_t *guid;
paulo@0: 
paulo@0: 	if (!(guid = malloc (GT_GUID_LEN)))
paulo@0: 		return NULL;
paulo@0: 
paulo@0: 	gt_guid_init (guid);
paulo@0: 
paulo@0: 	return guid;
paulo@0: }
paulo@0: 
paulo@0: int gt_guid_cmp (const gt_guid_t *a, const gt_guid_t *b)
paulo@0: {
paulo@0: 	if (!a)
paulo@0: 		return (b == NULL ? 0 : -1);
paulo@0: 	else if (!b)
paulo@0: 		return (a == NULL ? 0 : +1);
paulo@0: 
paulo@0: 	return memcmp (a, b, GT_GUID_LEN);
paulo@0: }
paulo@0: 
paulo@0: char *gt_guid_str (const gt_guid_t *guid)
paulo@0: {
paulo@0: 	static char    buf[128];
paulo@0: 	unsigned char  c;
paulo@0: 	int            pos;
paulo@0: 	int            len;
paulo@0: 
paulo@0: 	if (!guid)
paulo@0: 		return NULL;
paulo@0: 
paulo@0: 	pos = 0;
paulo@0: 	len = GT_GUID_LEN;
paulo@0: 
paulo@0: 	while (len-- > 0)
paulo@0: 	{
paulo@0: 		c = *guid++;
paulo@0: 
paulo@0: 		buf[pos++] = bin_to_hex[(c & 0xf0) >> 4];
paulo@0: 		buf[pos++] = bin_to_hex[(c & 0x0f)];
paulo@0: 	}
paulo@0: 
paulo@0: 	buf[pos] = 0;
paulo@0: 
paulo@0: 	return buf;
paulo@0: }
paulo@0: 
paulo@0: gt_guid_t *gt_guid_dup (const gt_guid_t *guid)
paulo@0: {
paulo@0: 	gt_guid_t *new_guid;
paulo@0: 
paulo@0: 	if (!(new_guid = malloc (GT_GUID_LEN)))
paulo@0: 		return NULL;
paulo@0: 
paulo@0: 	memcpy (new_guid, guid, GT_GUID_LEN);
paulo@0: 
paulo@0: 	return new_guid;
paulo@0: }
paulo@0: 
paulo@0: static unsigned char hex_char_to_bin (char x)
paulo@0: {
paulo@0: 	if (x >= '0' && x <= '9')
paulo@0: 		return (x - '0');
paulo@0: 
paulo@0: 	x = toupper (x);
paulo@0: 
paulo@0: 	return ((x - 'A') + 10);
paulo@0: }
paulo@0: 
paulo@0: static int hex_to_bin (const char *hex, unsigned char *bin, int len)
paulo@0: {
paulo@0: 	unsigned char value;
paulo@0: 
paulo@0: 	while (isxdigit (hex[0]) && isxdigit (hex[1]) && len-- > 0)
paulo@0: 	{
paulo@0: 		value  = (hex_char_to_bin (*hex++) << 4) & 0xf0;
paulo@0: 		value |= (hex_char_to_bin (*hex++)       & 0x0f);
paulo@0: 		*bin++ = value;
paulo@0: 	}
paulo@0: 
paulo@0:    return (len <= 0) ? TRUE : FALSE;
paulo@0: }
paulo@0: 
paulo@0: gt_guid_t *gt_guid_bin (const char *guid_ascii)
paulo@0: {
paulo@0: 	gt_guid_t *guid;
paulo@0: 
paulo@0: 	if (!guid_ascii)
paulo@0: 		return NULL;
paulo@0: 
paulo@0: 	if (!(guid = malloc (GT_GUID_LEN)))
paulo@0: 		return NULL;
paulo@0: 
paulo@0: 	if (!hex_to_bin (guid_ascii, guid, GT_GUID_LEN))
paulo@0: 	{
paulo@0: 		free (guid);
paulo@0: 		return NULL;
paulo@0: 	}
paulo@0: 
paulo@0: 	return guid;
paulo@0: }
paulo@0: 
paulo@0: /*****************************************************************************/
paulo@0: 
paulo@0: BOOL gt_guid_is_empty (const gt_guid_t *guid)
paulo@0: {
paulo@0: 	if (!guid)
paulo@0: 		return TRUE;
paulo@0: 
paulo@0: 	return memcmp (guid, zero_guid, GT_GUID_LEN) == 0;
paulo@0: }
paulo@0: 
paulo@0: /*****************************************************************************/
paulo@0: 
paulo@0: /*
paulo@0:  * Load the client GUID for this node.
paulo@0:  */
paulo@0: static gt_guid_t *get_client_id (char *conf_path)
paulo@0: {
paulo@0: 	FILE      *f;
paulo@0: 	gt_guid_t *client_id = NULL;
paulo@0: 	char      *buf       = NULL;
paulo@0: 
paulo@0: 	/*
paulo@0: 	 * There are people who distribute giFT packages which include the
paulo@0: 	 * developer's client-id file. These packages (mainly KCeasy derivatives,
paulo@0: 	 * I think) are widely enough distributed that other gnutella developers
paulo@0: 	 * have noticed the problem and notified me. To prevent this problem in
paulo@0: 	 * future versions I have forced randomization of the GUID on each startup
paulo@0: 	 * below. --mkern
paulo@0: 	 */
paulo@0: #if 0
paulo@0: 	if ((f = fopen (gift_conf_path (conf_path), "r")))
paulo@0: 	{
paulo@0: 		while (file_read_line (f, &buf))
paulo@0: 		{
paulo@0: 			char *id;
paulo@0: 			char *line;
paulo@0: 
paulo@0: 			free (client_id);
paulo@0: 			client_id = NULL;
paulo@0: 
paulo@0: 			line = buf;
paulo@0: 			id = string_sep_set (&line, "\r\n");
paulo@0: 
paulo@0: 			if (string_isempty (id))
paulo@0: 				continue;
paulo@0: 
paulo@0: 			client_id = gt_guid_bin (id);
paulo@0: 		}
paulo@0: 
paulo@0: 		fclose (f);
paulo@0: 	}
paulo@0: #endif
paulo@0: 
paulo@0: 	/* TODO: regenerate when client guid is pretty old */
paulo@0: 	if (client_id != NULL)
paulo@0: 		return client_id;
paulo@0: 
paulo@0: 	/*
paulo@0: 	 * Create a new client identifier
paulo@0: 	 */
paulo@0: 	client_id = gt_guid_new ();
paulo@0: 	assert (client_id != NULL);
paulo@0: 
paulo@0: 	/* store the id in ~/.giFT/Gnutella/clientid */
paulo@0: 	if (!(f = fopen (gift_conf_path (conf_path), "w")))
paulo@0: 	{
paulo@0: 		GIFT_ERROR (("clientid storage file: %s", GIFT_STRERROR ()));
paulo@0: 		return client_id;
paulo@0: 	}
paulo@0: 
paulo@0: 	fprintf (f, "%s\n", gt_guid_str (client_id));
paulo@0: 	fclose (f);
paulo@0: 
paulo@0: 	return client_id;
paulo@0: }
paulo@0: 
paulo@0: void gt_guid_self_init (void)
paulo@0: {
paulo@0: 	GT_SELF_GUID = get_client_id ("Gnutella/client-id");
paulo@0: 
paulo@0: 	/* remove the old clientid file which used an inferior random number
paulo@0: 	 * generator */
paulo@0: 	remove (gift_conf_path ("Gnutella/clientid"));
paulo@0: }
paulo@0: 
paulo@0: void gt_guid_self_cleanup (void)
paulo@0: {
paulo@0: 	free (GT_SELF_GUID);
paulo@0: 	GT_SELF_GUID = NULL;
paulo@0: }