paulo@0: /*
paulo@0:  * $Id: query_reply.c,v 1.3 2004/03/24 06:35:10 hipnod 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 "message/msg_handler.h"
paulo@0: 
paulo@0: #include "sha1.h"
paulo@0: #include "xml.h"
paulo@0: 
paulo@0: #include "gt_search.h"
paulo@0: 
paulo@0: #include "gt_urn.h"
paulo@0: #include "gt_ban.h"
paulo@0: 
paulo@0: #include "gt_share_file.h"
paulo@0: 
paulo@0: #include <libgift/mime.h>
paulo@0: 
paulo@0: /*****************************************************************************/
paulo@0: 
paulo@0: /*
paulo@0:  * Whether to attach the number of hops each result travelled as a metadata
paulo@0:  * field "Hops". Interesting to see but probably not too useful for the
paulo@0:  * average user, and so disabled by default.
paulo@0:  */
paulo@0: #define HOPS_AS_META         gt_config_get_int("search/hops_as_meta=0")
paulo@0: 
paulo@0: /*****************************************************************************/
paulo@0: 
paulo@0: extern void gt_parse_extended_data (char *ext_block, gt_urn_t **r_urn,
paulo@0:                                     Dataset **r_meta); /* query.c */
paulo@0: 
paulo@0: /*****************************************************************************/
paulo@0: 
paulo@0: static void add_meta (ds_data_t *key, ds_data_t *value, FileShare *file)
paulo@0: {
paulo@0: 	char *keystr   = key->data;
paulo@0: 	char *valuestr = value->data;
paulo@0: 
paulo@0: 	share_set_meta (file, keystr, valuestr);
paulo@0: }
paulo@0: 
paulo@0: /* parse XML data right before the client guid */
paulo@0: static void parse_xml_block (GtPacket *packet, size_t xml_bin_len,
paulo@0:                              Share **results, size_t hits)
paulo@0: {
paulo@0: 	int      old_offset;
paulo@0: 	char    *xml;
paulo@0: 	uint8_t  savechr;
paulo@0: 
paulo@0: 	/* if the length is one there is only the null terminator */
paulo@0: 	if (xml_bin_len < 1)
paulo@0: 		return;
paulo@0: 
paulo@0: 	/*
paulo@0: 	 * Look for the XML before the client guid. Subtract the length of the
paulo@0: 	 * client guid and the size of the XML.
paulo@0: 	 */
paulo@0: 	old_offset = gt_packet_seek (packet, packet->len - 16 - xml_bin_len);
paulo@0: 
paulo@0: 	/* hopefully, if xml_bin_len is bogus this will fail */
paulo@0: 	if (old_offset < 0)
paulo@0: 		return;
paulo@0: 
paulo@0: 	xml = gt_packet_get_ustr (packet, xml_bin_len);
paulo@0: 
paulo@0: 	if (!xml)
paulo@0: 		return;
paulo@0: 
paulo@0: 	/*
paulo@0: 	 * Null terminate the packet even if the remote end didn't.  We know this
paulo@0: 	 * is safe because the client GUID resides after the XML, and is 16 bytes
paulo@0: 	 * long.
paulo@0: 	 *
paulo@0: 	 * Note that the null char should be at xml[xml_bin_len - 1], so we end up
paulo@0: 	 * actually null-terminating twice if the XML is already terminated.
paulo@0: 	 * gt_xml_parse_indexed must take this into account (and it does by
paulo@0: 	 * largely ignoring xml_bin_len when the XML is plaintext).
paulo@0: 	 */
paulo@0: 	savechr = xml[xml_bin_len];
paulo@0: 	xml[xml_bin_len] = 0;
paulo@0: 
paulo@0: 	if (XML_DEBUG)
paulo@0: 		GT->dbg (GT, "xmldata=%s", xml);
paulo@0: 
paulo@0: 	/*
paulo@0: 	 * The XML before the client guid that we are parsing has a special
paulo@0: 	 * property "index" indicating which share the XML property corresponds
paulo@0: 	 * to, and so needs to be handled differently from XML appearing in
paulo@0: 	 * each individual hit.
paulo@0: 	 */
paulo@0: 	gt_xml_parse_indexed (xml, xml_bin_len, results, hits);
paulo@0: 
paulo@0: 	/* put the saved character back */
paulo@0: 	xml[xml_bin_len] = savechr;
paulo@0: }
paulo@0: 
paulo@0: /*
paulo@0:  * Attach the travelled hops as a metadata field.
paulo@0:  */
paulo@0: static void attach_hops (Share *share, int hops)
paulo@0: {
paulo@0: 	char buf[12];
paulo@0: 
paulo@0: 	if (!HOPS_AS_META)
paulo@0: 		return;
paulo@0: 
paulo@0: 	snprintf (buf, sizeof (buf) - 1, "%u", hops);
paulo@0: 	share_set_meta (share, "Hops", buf);
paulo@0: }
paulo@0: 
paulo@0: void gt_query_hits_parse (GtPacket *packet, GtSearch *search,
paulo@0:                           TCPC *c, gt_guid_t *client_guid)
paulo@0: {
paulo@0: 	uint8_t      count;
paulo@0: 	in_port_t    port;
paulo@0: 	in_addr_t    host;
paulo@0: 	uint32_t     speed;
paulo@0: 	Share       *results[255];
paulo@0: 	uint16_t     xml_len         = 0;
paulo@0: 	int          i, availability = 1;
paulo@0: 	BOOL         firewalled      = FALSE;
paulo@0: 	int          total;
paulo@0: 
paulo@0: 	count = gt_packet_get_uint8  (packet);
paulo@0: 	port  = gt_packet_get_port   (packet);
paulo@0: 	host  = gt_packet_get_ip     (packet);
paulo@0: 	speed = gt_packet_get_uint32 (packet);
paulo@0: 
paulo@0: 	/* check if this host is banned */
paulo@0: 	if (gt_ban_ipv4_is_banned (host))
paulo@0: 	{
paulo@0: 		GT->dbg (GT, "discarding search results from %s [address banned]",
paulo@0: 		         net_ip_str (host));
paulo@0: 		return;
paulo@0: 	}
paulo@0: 
paulo@0: 	for (i = 0; i < count; i++)
paulo@0: 	{
paulo@0: 		uint32_t       index;
paulo@0: 		uint32_t       size;
paulo@0: 		char          *fname, *data;
paulo@0: 		gt_urn_t      *urn  = NULL;
paulo@0: 		Dataset       *meta = NULL;
paulo@0: 		Share         *file;
paulo@0: 
paulo@0: 		index = gt_packet_get_uint32 (packet);
paulo@0: 		size  = gt_packet_get_uint32 (packet);
paulo@0: 		fname = gt_packet_get_str    (packet);
paulo@0: 		data  = gt_packet_get_str    (packet);
paulo@0: 
paulo@0: 		/* If there was an error parsing the packet (not enough results),
paulo@0: 		 * stop parsing */
paulo@0: 		if (gt_packet_error (packet))
paulo@0: 			break;
paulo@0: 
paulo@0: 		if (!fname || string_isempty (fname))
paulo@0: 		{
paulo@0: 			results[i] = NULL;
paulo@0: 			continue;
paulo@0: 		}
paulo@0: 
paulo@0: 		gt_parse_extended_data (data, &urn, &meta);
paulo@0: 
paulo@0: 		/*
paulo@0: 		 * WARNING: calling gt_urn_data here assumes sha1.
paulo@0: 		 *
paulo@0: 		 * TODO: this is a potential bug if gt_share_new() makes assumptions
paulo@0: 		 * about the hash data's size and gt_urn_t changes to be multiple
paulo@0: 		 * sizes later.
paulo@0: 		 */
paulo@0: 		if (!(file = gt_share_new (fname, index, size, gt_urn_data (urn))))
paulo@0: 		{
paulo@0: 			GIFT_ERROR (("error making fileshare, why?"));
paulo@0: 
paulo@0: 			dataset_clear (meta);
paulo@0: 			free (urn);
paulo@0: 
paulo@0: 			/* make sure we find out about it if we're missing results ;) */
paulo@0: 			assert (0);
paulo@0: 
paulo@0: 			results[i] = NULL;
paulo@0: 			continue;
paulo@0: 		}
paulo@0: 
paulo@0: 		/* HACK: set the mimetype from the file extension */
paulo@0: 		share_set_mime (file, mime_type (fname));
paulo@0: 
paulo@0: 		dataset_foreach (meta, DS_FOREACH(add_meta), file);
paulo@0: 
paulo@0: 		/* Attach the hops the search travelled as a metadata field */
paulo@0: 		attach_hops (file, gt_packet_hops (packet));
paulo@0: 
paulo@0: 		dataset_clear (meta);
paulo@0: 		free (urn);
paulo@0: 
paulo@0: 		results[i] = file;
paulo@0: 	}
paulo@0: 
paulo@0: 	total = i;
paulo@0: 
paulo@0: 	/* look for the query hit descriptor */
paulo@0: 	if (!gt_packet_error (packet) &&
paulo@0: 	    packet->len - packet->offset >= 16 + 7 /* min qhd len */)
paulo@0: 	{
paulo@0: 		unsigned char *vendor;
paulo@0: 		uint8_t        eqhd_len;
paulo@0: 		uint8_t        eqhd[2];
paulo@0: 
paulo@0: 		vendor   = gt_packet_get_ustr  (packet, 4);
paulo@0: 		eqhd_len = gt_packet_get_uint8 (packet);
paulo@0: 		eqhd[0]  = gt_packet_get_uint8 (packet);
paulo@0: 		eqhd[1]  = gt_packet_get_uint8 (packet);
paulo@0: 
paulo@0: 		/* set availability to 0 or 1 depending on the busy flag */
paulo@0: 		availability = ((eqhd[0] & EQHD1_HAS_BUSY) &&
paulo@0: 		                !(eqhd[1] & EQHD2_BUSY_FLAG)) ? 1 : 0;
paulo@0: 
paulo@0: 		/* set firewalled status based on the PUSH flag */
paulo@0: 		firewalled   = BOOL_EXPR ((eqhd[0] & EQHD1_PUSH_FLAG) &&
paulo@0: 		                          (eqhd[1] & EQHD2_HAS_PUSH));
paulo@0: 
paulo@0: 		/*
paulo@0: 		 * Check for an XML metadata block, that is usually present
paulo@0: 		 * when the size of the "public area" is 4
paulo@0: 		 */
paulo@0: 		if (eqhd_len >= 4)
paulo@0: 			xml_len = gt_packet_get_uint16 (packet);
paulo@0: 
paulo@0: 		if (xml_len > 0)
paulo@0: 		{
paulo@0: 			if (XML_DEBUG)
paulo@0: 			{
paulo@0: 				char str[5] = { 0 };
paulo@0: 
paulo@0: 				if (vendor)
paulo@0: 					memcpy (str, vendor, 4);
paulo@0: 
paulo@0: 				GT->dbg (GT, "(%s) xml_len=%d", str, xml_len);
paulo@0: 			}
paulo@0: 
paulo@0: 			parse_xml_block (packet, xml_len, results, total);
paulo@0: 		}
paulo@0: 
paulo@0: #if 0
paulo@0: 		if (MSG_DEBUG)
paulo@0: 		{
paulo@0: 			GT->DBGFN (GT, "vendor = %s, qhd_len = %u, qhd_0 = %x, qhd_1 = %x,"
paulo@0: 			           " availability = %i, firewalled = %i",
paulo@0: 			           make_str (vendor, 4), qhd_len, qhd[0], qhd[1],
paulo@0: 			           availability, firewalled);
paulo@0: 		}
paulo@0: #endif
paulo@0: 	}
paulo@0: 
paulo@0: 	/* send the results to the interface protocol */
paulo@0: 	for (i = 0; i < total; i++)
paulo@0: 	{
paulo@0: 		if (results[i])
paulo@0: 		{
paulo@0: 			gt_search_reply (search, c, host, port, client_guid, availability,
paulo@0: 			                 firewalled, results[i]);
paulo@0: 
paulo@0: 			gt_share_unref (results[i]);
paulo@0: 		}
paulo@0: 	}
paulo@0: }
paulo@0: 
paulo@0: /* should split this up into two routines */
paulo@0: GT_MSG_HANDLER(gt_msg_query_reply)
paulo@0: {
paulo@0: 	GtSearch   *search;
paulo@0: 	int         save_offset;
paulo@0: 	gt_guid_t  *client_guid;
paulo@0: 
paulo@0: 	/* Each client has a unique identifier at the end of the
paulo@0: 	 * packet.  Grab that first. */
paulo@0: 	if (packet->len < 16)
paulo@0: 	{
paulo@0: 		if (MSG_DEBUG)
paulo@0: 			GT->DBGSOCK (GT, c, "illegal query response packet, < 16 bytes");
paulo@0: 
paulo@0: 		return;
paulo@0: 	}
paulo@0: 
paulo@0: 	/* hack the offset in the packet */
paulo@0: 	save_offset = packet->offset;
paulo@0: 	packet->offset = packet->len - 16;
paulo@0: 
paulo@0: 	client_guid = gt_packet_get_ustr (packet, 16);
paulo@0: 
paulo@0: 	/* put the offset back */
paulo@0: 	packet->offset = save_offset;
paulo@0: 
paulo@0: 	if (!(search = gt_search_find (gt_packet_guid (packet)))
paulo@0: 		/*&& query_cache_lookup (packet->guid)*/)
paulo@0: 	{
paulo@0: 		/* TODO: support forwarding of query responses by
paulo@0: 		 * looking up their destinations in the guid cache */
paulo@0: 
paulo@0: 		/*gt_route_forward_packet (packet, c);*/
paulo@0: 
paulo@0: 		/* add the client GUID to the push cache: in case of a
paulo@0: 		 * push request we know where to send it */
paulo@0: 		/*push_cache_add (client_guid, c);*/
paulo@0: 
paulo@0: 		return;
paulo@0: 	}
paulo@0: 
paulo@0: 	gt_query_hits_parse (packet, search, c, client_guid);
paulo@0: }