1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/src/gt_connect.c	Sat Feb 20 21:18:28 2010 -0800
     1.3 @@ -0,0 +1,544 @@
     1.4 +/*
     1.5 + * $Id: gt_connect.c,v 1.55 2005/01/04 15:03:40 mkern Exp $
     1.6 + *
     1.7 + * Copyright (C) 2001-2003 giFT project (gift.sourceforge.net)
     1.8 + *
     1.9 + * This program is free software; you can redistribute it and/or modify it
    1.10 + * under the terms of the GNU General Public License as published by the
    1.11 + * Free Software Foundation; either version 2, or (at your option) any
    1.12 + * later version.
    1.13 + *
    1.14 + * This program is distributed in the hope that it will be useful, but
    1.15 + * WITHOUT ANY WARRANTY; without even the implied warranty of
    1.16 + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    1.17 + * General Public License for more details.
    1.18 + */
    1.19 +
    1.20 +#include "gt_gnutella.h"
    1.21 +#include "gt_version.h"
    1.22 +
    1.23 +#include "gt_connect.h"
    1.24 +#include "gt_accept.h"
    1.25 +#include "gt_packet.h"
    1.26 +
    1.27 +#include "gt_node.h"
    1.28 +#include "gt_node_list.h"
    1.29 +#include "gt_utils.h"
    1.30 +
    1.31 +#include "gt_search.h"
    1.32 +#include "gt_netorg.h"
    1.33 +
    1.34 +#include "gt_node_cache.h"
    1.35 +
    1.36 +#include "message/gt_message.h"   /* gnutella_start_connection */
    1.37 +
    1.38 +/*****************************************************************************/
    1.39 +
    1.40 +static void send_connect  (int fd, input_id id, TCPC *c);
    1.41 +static void recv_headers  (int fd, input_id id, TCPC *c);
    1.42 +static void send_response (int fd, input_id id, TCPC *c);
    1.43 +static BOOL send_final    (TCPC *c);
    1.44 +
    1.45 +/*****************************************************************************/
    1.46 +
    1.47 +static BOOL handshake_timeout (TCPC *c)
    1.48 +{
    1.49 +	GtNode *node = GT_NODE(c);
    1.50 +
    1.51 +	node->handshake_timer = 0;
    1.52 +
    1.53 +	if (!(node->state & GT_NODE_CONNECTED))
    1.54 +	{
    1.55 +		gt_node_disconnect (c);
    1.56 +		return FALSE;
    1.57 +	}
    1.58 +
    1.59 +	return FALSE;
    1.60 +}
    1.61 +
    1.62 +void gnutella_set_handshake_timeout (TCPC *c, time_t delay)
    1.63 +{
    1.64 +	timer_remove (GT_NODE(c)->handshake_timer);
    1.65 +
    1.66 +	GT_NODE(c)->handshake_timer = timer_add (delay,
    1.67 +	                                         (TimerCallback)handshake_timeout, 
    1.68 +	                                         c);
    1.69 +}
    1.70 +
    1.71 +int gt_connect (GtNode *node)
    1.72 +{
    1.73 +	TCPC   *c;
    1.74 +
    1.75 +	if (!node)
    1.76 +		return -1;
    1.77 +
    1.78 +#if 0
    1.79 +	if (GT_CONN(node) != NULL)
    1.80 +	{
    1.81 +		GT->dbg (GT, "duplicate connection?: %p", GT_CONN(node));
    1.82 +		return -1;
    1.83 +	}
    1.84 +
    1.85 +	if (node->state != GT_NODE_DISCONNECTED)
    1.86 +	{
    1.87 +		GT->dbg (GT, "state = %i??", node->state);
    1.88 +		return -1;
    1.89 +	}
    1.90 +#endif
    1.91 +
    1.92 +	/* this must be called only on disconnected nodes */
    1.93 +	assert (GT_CONN(node) == NULL);
    1.94 +	assert (node->state == GT_NODE_DISCONNECTED);
    1.95 +
    1.96 +#if 0
    1.97 +	if (!conn_auth (c, TRUE))
    1.98 +		return -1;
    1.99 +#endif
   1.100 +
   1.101 +	/* set this early: gt_netorg relies on this being set in order
   1.102 +	 * to check if it should access the gwebcaches */
   1.103 +	node->start_connect_time = time (NULL);
   1.104 +
   1.105 +	/* make sure port is valid */
   1.106 +	if (node->gt_port == 0)
   1.107 +	{
   1.108 +		GT->DBGFN (GT, "bad port on node %s", net_ip_str (node->ip));
   1.109 +		return -1;
   1.110 +	}
   1.111 +
   1.112 +	/* make outgoing connection */
   1.113 +	if (!(c = tcp_open (node->ip, node->gt_port, FALSE)))
   1.114 +		return -1;
   1.115 +
   1.116 +	gt_node_connect (node, c);
   1.117 +
   1.118 +	gt_node_state_set (node, GT_NODE_CONNECTING_1);
   1.119 +	node->incoming = FALSE;
   1.120 +
   1.121 +	/* set the connection timeout */
   1.122 +	gnutella_set_handshake_timeout (c, TIMEOUT_1 * SECONDS);
   1.123 +
   1.124 +	input_add (c->fd, c, INPUT_WRITE,
   1.125 +	           (InputCallback)send_connect, 0);
   1.126 +
   1.127 +	return c->fd;
   1.128 +}
   1.129 +
   1.130 +static void send_connect (int fd, input_id id, TCPC *c)
   1.131 +{
   1.132 +	if (net_sock_error (c->fd))
   1.133 +	{
   1.134 +		gt_node_disconnect (c);
   1.135 +		return;
   1.136 +	}
   1.137 +
   1.138 +	/* Send the connect string along with our headers */
   1.139 +	if (!gnutella_send_connection_headers (c, "GNUTELLA CONNECT/0.6"))
   1.140 +	{
   1.141 +		gt_node_error (c, NULL);
   1.142 +		gt_node_disconnect (c);
   1.143 +		return;
   1.144 +	}
   1.145 +
   1.146 +	/* we connected ok, so give the peer some more time */
   1.147 +	gnutella_set_handshake_timeout (c, TIMEOUT_2 * SECONDS);
   1.148 +
   1.149 +	input_remove (id);
   1.150 +	input_add (fd, c, INPUT_READ,
   1.151 +	           (InputCallback)recv_headers, 0);
   1.152 +}
   1.153 +
   1.154 +BOOL gnutella_parse_response_headers (char *reply, Dataset **r_headers)
   1.155 +{
   1.156 +	int       code;    /* 200, 404, ... */
   1.157 +	char     *response;
   1.158 +	Dataset  *headers   = NULL;
   1.159 +
   1.160 +	response = string_sep (&reply, "\r\n");
   1.161 +
   1.162 +	if (!response)
   1.163 +		return FALSE;
   1.164 +
   1.165 +	/*    */     string_sep (&response, " ");  /* shift past HTTP/1.1 */
   1.166 +	code = ATOI (string_sep (&response, " ")); /* shift past 200 */
   1.167 +
   1.168 +	/* parse the headers */
   1.169 +	gt_http_header_parse (reply, &headers);
   1.170 +
   1.171 +	if (r_headers)
   1.172 +		*r_headers = headers;
   1.173 +	else
   1.174 +		dataset_clear (headers);
   1.175 +
   1.176 +	if (code >= 200 && code <= 299)
   1.177 +		return TRUE;
   1.178 +
   1.179 +	return FALSE;
   1.180 +}
   1.181 +
   1.182 +static time_t parse_uptime (Dataset *d)
   1.183 +{
   1.184 +	char   *str;
   1.185 +	int     days, hours, mins;
   1.186 +	int     n;
   1.187 +
   1.188 +	if (!(str = dataset_lookupstr (d, "uptime")))
   1.189 +		return 0;
   1.190 +	
   1.191 +	string_lower (str);
   1.192 +
   1.193 +	if ((n = sscanf (str, "%dd %dh %dm", &days, &hours, &mins)) != 3)
   1.194 +		return 0;
   1.195 +
   1.196 +	if (HANDSHAKE_DEBUG)
   1.197 +	{
   1.198 +		GT->dbg (GT, "uptime parsed: %d days, %d hours, %d minutes",
   1.199 +		         days, hours, mins);
   1.200 +	}
   1.201 +
   1.202 +	return days * EDAYS + hours * EHOURS + mins * EMINUTES;
   1.203 +}
   1.204 +
   1.205 +/* look in a header field for nodes, and register them */
   1.206 +static void extract_nodes (Dataset *d, in_addr_t src,
   1.207 +                           const char *field, gt_node_class_t klass)
   1.208 +{
   1.209 +	char   *str;
   1.210 +	char   *value;
   1.211 +	time_t  now;
   1.212 +
   1.213 +	now = time (NULL);
   1.214 +
   1.215 +	if (!(str = dataset_lookupstr (d, field)))
   1.216 +		return;
   1.217 +
   1.218 +	while ((value = string_sep (&str, ",")))
   1.219 +	{
   1.220 +		in_addr_t  ip;
   1.221 +		in_port_t  port;
   1.222 +
   1.223 +		ip   = net_ip (string_sep (&value, ":"));
   1.224 +		port = ATOI   (value);
   1.225 +
   1.226 +		if (port == (in_port_t) -1 || port == 0)
   1.227 +			continue;
   1.228 +
   1.229 +		if (ip == INADDR_NONE || ip == 0)
   1.230 +			continue;
   1.231 +
   1.232 +		if (gt_is_local_ip (ip, src))
   1.233 +			continue;
   1.234 +
   1.235 +		gt_node_cache_add_ipv4 (ip, port, klass, now, 0, src);
   1.236 +	}
   1.237 +
   1.238 +	gt_node_cache_trace ();
   1.239 +}
   1.240 +
   1.241 +static void recv_headers (int fd, input_id id, TCPC *c)
   1.242 +{
   1.243 +	FDBuf   *buf;
   1.244 +	char    *response;
   1.245 +	size_t   response_len = 0;
   1.246 +	int      n;
   1.247 +	BOOL     ok;
   1.248 +	time_t   uptime;
   1.249 +	GtNode  *node         = GT_NODE(c);
   1.250 +
   1.251 +	buf = tcp_readbuf (c);
   1.252 +
   1.253 +	if ((n = fdbuf_delim (buf, "\n")) < 0)
   1.254 +	{
   1.255 +		GT->DBGFN (GT, "error reading headers: %s", GIFT_NETERROR ());
   1.256 +		gt_node_disconnect (c);
   1.257 +		return;
   1.258 +	}
   1.259 +
   1.260 +	if (gt_fdbuf_full (buf))
   1.261 +	{
   1.262 +		gt_node_disconnect (c);
   1.263 +		return;
   1.264 +	}
   1.265 +
   1.266 +	if (n > 0)
   1.267 +		return;
   1.268 +
   1.269 +	response = fdbuf_data (buf, &response_len);
   1.270 +	if (!gt_http_header_terminated (response, response_len))
   1.271 +		return;
   1.272 +
   1.273 +	fdbuf_release (buf);
   1.274 +
   1.275 +	if (HANDSHAKE_DEBUG)
   1.276 +		GT->DBGSOCK (GT, c, "node handshake response:\n%s", response);
   1.277 +
   1.278 +	/* parse and store the response */
   1.279 +	ok = gnutella_parse_response_headers (response, &node->hdr);
   1.280 +
   1.281 +	/* extract nodes */
   1.282 +	extract_nodes (node->hdr, node->ip, "x-try-ultrapeers", GT_NODE_ULTRA);
   1.283 +	extract_nodes (node->hdr, node->ip, "x-try", GT_NODE_NONE);
   1.284 +
   1.285 +	/* grab the uptime from the "Uptime: " header and update this node */
   1.286 +	if ((uptime = parse_uptime (node->hdr)) > 0)
   1.287 +	{
   1.288 +		gt_node_cache_add_ipv4 (node->ip, node->gt_port,
   1.289 +		                        GT_NODE_ULTRA, time (NULL), uptime, node->ip);
   1.290 +
   1.291 +		/* XXX: remove the item immediately so we trigger the side effect of
   1.292 +		 * adding this node to the stable list */
   1.293 +		gt_node_cache_del_ipv4 (node->ip, node->gt_port);
   1.294 +	}
   1.295 +
   1.296 +	if (!ok)
   1.297 +	{
   1.298 +		gt_node_disconnect (c);
   1.299 +		return;
   1.300 +	}
   1.301 +
   1.302 +	input_remove (id);
   1.303 +	input_add (fd, c, INPUT_WRITE,
   1.304 +	           (InputCallback)send_response, 0);
   1.305 +}
   1.306 +
   1.307 +static void send_response (int fd, input_id id, TCPC *c)
   1.308 +{
   1.309 +	if (net_sock_error (c->fd))
   1.310 +	{
   1.311 +		gt_node_error (c, NULL);
   1.312 +		gt_node_disconnect (c);
   1.313 +		return;
   1.314 +	}
   1.315 +
   1.316 +	if (!gnutella_auth_connection (c))
   1.317 +	{
   1.318 +		gt_node_error (c, "[outgoing] connection not authorized");
   1.319 +		gt_node_disconnect (c);
   1.320 +		return;
   1.321 +	}
   1.322 +
   1.323 +	if (!send_final (c))
   1.324 +	{
   1.325 +		gt_node_error (c, NULL);
   1.326 +		GT->DBGSOCK (GT, c, "error at stage 3 of handshake");
   1.327 +		gt_node_disconnect (c);
   1.328 +		return;
   1.329 +	}
   1.330 +
   1.331 +	/* ok, startup this connection */
   1.332 +	input_remove (id);
   1.333 +	input_add (fd, c, INPUT_WRITE,
   1.334 +	           (InputCallback)gnutella_start_connection, 0);
   1.335 +}
   1.336 +
   1.337 +/*****************************************************************************/
   1.338 +
   1.339 +static GtNode *append_node (TCPC *c, GtNode *node, String *s)
   1.340 +{
   1.341 +	if (s->str[s->len - 1] != ' ')
   1.342 +		string_append (s, ",");
   1.343 +
   1.344 +	string_appendf (s, "%s:%hu", net_ip_str (node->ip), node->gt_port);
   1.345 +	return NULL;
   1.346 +}
   1.347 +
   1.348 +static void append_crawler_headers (String *msg)
   1.349 +{
   1.350 +	if (gt_conn_length (GT_NODE_ULTRA, GT_NODE_CONNECTED) > 0)
   1.351 +	{
   1.352 +		string_append (msg, "Peers: ");
   1.353 +		gt_conn_foreach (GT_CONN_FOREACH(append_node), msg,
   1.354 +		                 GT_NODE_ULTRA, GT_NODE_CONNECTED, 0);
   1.355 +		string_append (msg, "\r\n");
   1.356 +	}
   1.357 +
   1.358 +	if (GT_SELF->klass & GT_NODE_ULTRA && 
   1.359 +	    gt_conn_length (GT_NODE_LEAF, GT_NODE_CONNECTED) > 0)
   1.360 +	{
   1.361 +		string_append (msg, "Leaves: ");
   1.362 +		gt_conn_foreach (GT_CONN_FOREACH(append_node), msg,
   1.363 +		                 GT_NODE_LEAF, GT_NODE_CONNECTED, 0);
   1.364 +		string_append (msg, "\r\n");
   1.365 +	}
   1.366 +}
   1.367 +
   1.368 +BOOL gnutella_send_connection_headers (TCPC *c, const char *header)
   1.369 +{
   1.370 +	String *msg;
   1.371 +
   1.372 +	if (!(msg = string_new (NULL, 0, 0, TRUE)))
   1.373 +		return FALSE;
   1.374 +
   1.375 +	string_appendf (msg, "%s\r\n", header);
   1.376 +
   1.377 +	string_append  (msg, "X-Query-Routing: 0.1\r\n");
   1.378 +	string_appendf (msg, "X-Ultrapeer: %s\r\n", 
   1.379 +	                (GT_SELF->klass & GT_NODE_ULTRA) ? "True" : "False");
   1.380 +
   1.381 +	/* append the client and version we are using */
   1.382 +	string_appendf (msg, "User-Agent: %s\r\n", gt_version ());
   1.383 +
   1.384 +	/* Add a header describing the remote IP of the peer */
   1.385 +	string_appendf (msg, "Remote-IP: %s\r\n", net_peer_ip (c->fd));
   1.386 +
   1.387 +	/* let remote end know it's ok to send vendor messages */
   1.388 +	string_appendf (msg, "Vendor-Message: 0.1\r\n");
   1.389 +
   1.390 +	/* support transmission of pings/pongs with GGEP appended */
   1.391 +	string_append  (msg, "GGEP: 0.5\r\n");
   1.392 +
   1.393 +	/* If this is the limewire crawler, append "Peers: " and "Leaves: "
   1.394 +	 * headers and close the connection */
   1.395 +	if (!c->outgoing && dataset_lookupstr (GT_NODE(c)->hdr, "crawler"))
   1.396 +		append_crawler_headers (msg);
   1.397 +
   1.398 +	/* append willingness to receive compressed data */
   1.399 +	string_append (msg, "Accept-Encoding: deflate\r\n");
   1.400 +		
   1.401 +	/* check whether the remote node sent us Accept-Encoding: deflate
   1.402 +	 * already */
   1.403 +	gnutella_mark_compression (GT_NODE(c));
   1.404 +
   1.405 +	/* compress data if we must */
   1.406 +	if (GT_NODE(c)->tx_deflated)
   1.407 +		string_append (msg, "Content-Encoding: deflate\r\n");
   1.408 +
   1.409 +	/* Add message terminator */
   1.410 +	string_append (msg, "\r\n");
   1.411 +
   1.412 +	if (HANDSHAKE_DEBUG)
   1.413 +		GT->DBGSOCK (GT, c, "sending node headers:\n%s", msg->str);
   1.414 +
   1.415 +	if (tcp_send (c, msg->str, msg->len) <= 0)
   1.416 +	{
   1.417 +		string_free (msg);
   1.418 +		return FALSE;
   1.419 +	}
   1.420 +
   1.421 +	string_free (msg);
   1.422 +	return TRUE;
   1.423 +}
   1.424 +
   1.425 +static BOOL send_final (TCPC *c)
   1.426 +{
   1.427 +	String *s;
   1.428 +	int     ret;
   1.429 +	int     len;
   1.430 +
   1.431 +	if (!(s = string_new (NULL, 0, 0, TRUE)))
   1.432 +		return FALSE;
   1.433 +
   1.434 +	/* append header acceptance line */
   1.435 +	string_append (s, "GNUTELLA/0.6 200 OK\r\n");
   1.436 +
   1.437 +	/* mark the connection as complete */
   1.438 +	gnutella_mark_compression (GT_NODE(c));
   1.439 +
   1.440 +	if (GT_NODE(c)->tx_deflated)
   1.441 +		string_append (s, "Content-Encoding: deflate\r\n");
   1.442 +
   1.443 +	/* append msg terminator */
   1.444 +	string_append (s, "\r\n");
   1.445 +
   1.446 +	if (HANDSHAKE_DEBUG)
   1.447 +		GT->DBGSOCK (GT, c, "sending final handshake:\n%s", s->str);
   1.448 +
   1.449 +	len = s->len;
   1.450 +	ret = tcp_send (c, s->str, s->len);
   1.451 +
   1.452 +	string_free (s);
   1.453 +
   1.454 +	if (ret != len)
   1.455 +		return FALSE;
   1.456 +
   1.457 +	return TRUE;
   1.458 +}
   1.459 +
   1.460 +/*****************************************************************************/
   1.461 +/* CONNECTABILITY TESTING */
   1.462 +
   1.463 +static void connect_test_result (GtNode *node, TCPC *c, BOOL success)
   1.464 +{
   1.465 +	GT->DBGFN (GT, "connect test to %s %s", net_ip_str (node->ip),
   1.466 +	           (success ? "succeeded" : "failed"));
   1.467 +
   1.468 +	node->firewalled = (success ? FALSE : TRUE);
   1.469 +	node->verified   = TRUE;
   1.470 +
   1.471 +	if (c)
   1.472 +	{
   1.473 +		tcp_close (c);
   1.474 +		node->gt_port_verify = NULL;
   1.475 +	}
   1.476 +}
   1.477 +
   1.478 +static void test_connectable (int fd, input_id id, TCPC *c)
   1.479 +{
   1.480 +	GtNode *node;
   1.481 +
   1.482 +	node = c->udata;
   1.483 +
   1.484 +	if (net_sock_error (c->fd))
   1.485 +	{
   1.486 +		connect_test_result (node, c, FALSE);
   1.487 +		return;
   1.488 +	}
   1.489 +
   1.490 +	/*
   1.491 +	 * Send two newlines, because some firewalls will let connections pass 
   1.492 +	 * through, but no data.
   1.493 +	 */
   1.494 +	tcp_send (c, "\n\n", 2);
   1.495 +	connect_test_result (node, c, TRUE);
   1.496 +}
   1.497 +
   1.498 +/*
   1.499 + * Test if the port of a peer we are connected to is connectable.  This lets a
   1.500 + * node know if it's firewalled.  We could use this info to mangle the 'push'
   1.501 + * flag on query hits from this node if it is a leaf.
   1.502 + *
   1.503 + * Mangling query hits would break any future checksum or signing algorithm on
   1.504 + * query hits though, so that isn't done.
   1.505 + */
   1.506 +void gt_connect_test (GtNode *node, in_port_t port)
   1.507 +{
   1.508 +	TCPC *new_c;
   1.509 +
   1.510 +	if (!port)
   1.511 +	{
   1.512 +		node->firewalled = TRUE;
   1.513 +		return;
   1.514 +	}
   1.515 +
   1.516 +	/* this needs some kind of local mode switch */
   1.517 +#if 0
   1.518 +	if (net_match_host (GT_NODE(c)->ip, "LOCAL"))
   1.519 +	{
   1.520 +		GT_NODE(c)->firewalled = TRUE;
   1.521 +		return;
   1.522 +	}
   1.523 +#endif
   1.524 +
   1.525 +	if (!node->incoming)
   1.526 +		return;
   1.527 +
   1.528 +	GT->DBGFN (GT, "starting connect test on %s:%hu", 
   1.529 +	           net_ip_str (node->ip), port);
   1.530 +
   1.531 +	if (!(new_c = tcp_open (node->ip, port, FALSE)))
   1.532 +	{
   1.533 +		GT->DBGFN (GT, "failed to open test connection to %s:%hu",
   1.534 +		           net_ip_str (node->ip), node->gt_port);
   1.535 +		return;
   1.536 +	}
   1.537 +
   1.538 +	if (node->gt_port_verify)
   1.539 +		tcp_close (node->gt_port_verify);
   1.540 +
   1.541 +	/* keep track of this connection */
   1.542 +	node->gt_port_verify = new_c;
   1.543 +	new_c->udata = node;
   1.544 +
   1.545 +	input_add (new_c->fd, new_c, INPUT_WRITE,
   1.546 +	           (InputCallback)test_connectable, TIMEOUT_DEF);
   1.547 +}