diff options
Diffstat (limited to 'protocols/jabber/s5bytestream.c')
| -rw-r--r-- | protocols/jabber/s5bytestream.c | 1153 | 
1 files changed, 1153 insertions, 0 deletions
| diff --git a/protocols/jabber/s5bytestream.c b/protocols/jabber/s5bytestream.c new file mode 100644 index 00000000..58a6c2e4 --- /dev/null +++ b/protocols/jabber/s5bytestream.c @@ -0,0 +1,1153 @@ +/***************************************************************************\ +*                                                                           * +*  BitlBee - An IRC to IM gateway                                           * +*  Jabber module - SOCKS5 Bytestreams ( XEP-0065 )                          * +*                                                                           * +*  Copyright 2007 Uli Meis <a.sporto+bee@gmail.com>                         * +*                                                                           * +*  This program 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 2 of the License, or        * +*  (at your option) any later version.                                      * +*                                                                           * +*  This program 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 this program; if not, write to the Free Software Foundation, Inc.,  * +*  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.              * +*                                                                           * +\***************************************************************************/ + +#include "jabber.h" +#include "sha1.h" +#include "lib/ftutil.h" +#include <poll.h> + +struct bs_transfer { + +	struct jabber_transfer *tf; + +	jabber_streamhost_t *sh; +	GSList *streamhosts; + +	enum  +	{  +		BS_PHASE_CONNECT,  +		BS_PHASE_CONNECTED,  +		BS_PHASE_REQUEST,  +		BS_PHASE_REPLY +	} phase; + +	/* SHA1( SID + Initiator JID + Target JID) */ +	char *pseudoadr; + +	gint connect_timeout; +	 +	char peek_buf[64]; +	int peek_buf_len; +}; + +struct socks5_message +{ +	unsigned char ver; +	union +	{ +		unsigned char cmd; +		unsigned char rep; +	} cmdrep; +	unsigned char rsv; +	unsigned char atyp; +	unsigned char addrlen; +	unsigned char address[40]; +	in_port_t port; +} __attribute__ ((packed));  + +char *socks5_reply_code[] = { +	"succeeded", +	"general SOCKS server failure", +	"connection not allowed by ruleset", +	"Network unreachable", +	"Host unreachable", +	"Connection refused", +	"TTL expired", +	"Command not supported", +	"Address type not supported", +	"unassigned"}; + +/* connect() timeout in seconds. */ +#define JABBER_BS_CONTIMEOUT 15 +/* listen timeout */ +#define JABBER_BS_LISTEN_TIMEOUT  90 + +/* very useful */ +#define ASSERTSOCKOP(op, msg) \ +	if( (op) == -1 ) \ +		return jabber_bs_abort( bt , msg ": %s", strerror( errno ) ); + +gboolean jabber_bs_abort( struct bs_transfer *bt, char *format, ... ); +void jabber_bs_canceled( file_transfer_t *ft , char *reason ); +void jabber_bs_free_transfer( file_transfer_t *ft ); +gboolean jabber_bs_connect_timeout( gpointer data, gint fd, b_input_condition cond ); +gboolean jabber_bs_poll( struct bs_transfer *bt, int fd, short *revents ); +gboolean jabber_bs_peek( struct bs_transfer *bt, void *buffer, int buflen ); + +void jabber_bs_recv_answer_request( struct bs_transfer *bt ); +gboolean jabber_bs_recv_read( gpointer data, gint fd, b_input_condition cond ); +gboolean jabber_bs_recv_write_request( file_transfer_t *ft ); +gboolean jabber_bs_recv_handshake( gpointer data, gint fd, b_input_condition cond ); +gboolean jabber_bs_recv_handshake_abort( struct bs_transfer *bt, char *error ); +int jabber_bs_recv_request( struct im_connection *ic, struct xt_node *node, struct xt_node *qnode ); + +gboolean jabber_bs_send_handshake_abort( struct bs_transfer *bt, char *error ); +gboolean jabber_bs_send_request( struct jabber_transfer *tf, GSList *streamhosts ); +gboolean jabber_bs_send_handshake( gpointer data, gint fd, b_input_condition cond ); +static xt_status jabber_bs_send_handle_activate( struct im_connection *ic, struct xt_node *node, struct xt_node *orig ); +void jabber_bs_send_activate( struct bs_transfer *bt ); + +/* + * Frees a bs_transfer struct and calls the SI free function + */ +void jabber_bs_free_transfer( file_transfer_t *ft) { +	struct jabber_transfer *tf = ft->data; +	struct bs_transfer *bt = tf->streamhandle; +	jabber_streamhost_t *sh; + +	if ( bt->connect_timeout ) +	{ +		b_event_remove( bt->connect_timeout ); +		bt->connect_timeout = 0; +	} + +	if ( tf->watch_in ) +		b_event_remove( tf->watch_in ); +	 +	if( tf->watch_out ) +		b_event_remove( tf->watch_out ); +	 +	g_free( bt->pseudoadr ); + +	while( bt->streamhosts ) +	{ +		sh = bt->streamhosts->data; +		bt->streamhosts = g_slist_remove( bt->streamhosts, sh ); +		g_free( sh->jid ); +		g_free( sh->host ); +		g_free( sh ); +	} +	 +	g_free( bt ); + +	jabber_si_free_transfer( ft ); +} + +/* + * Checks if buflen data is available on the socket and + * writes it to buffer if that's the case. + */ +gboolean jabber_bs_peek( struct bs_transfer *bt, void *buffer, int buflen ) +{ +	int ret; +	int fd = bt->tf->fd; + +	if( buflen > sizeof( bt->peek_buf ) ) +		return jabber_bs_abort( bt, "BUG: %d > sizeof(peek_buf)", buflen ); + +	ASSERTSOCKOP( ret = recv( fd, bt->peek_buf + bt->peek_buf_len, +		buflen - bt->peek_buf_len, 0 ), "recv() on SOCKS5 connection" ); + +	if( ret == 0 ) +		return jabber_bs_abort( bt, "Remote end closed connection" ); +	 +	bt->peek_buf_len += ret; +	memcpy( buffer, bt->peek_buf, bt->peek_buf_len ); +	 +	if( bt->peek_buf_len == buflen ) +	{ +		/* If we have everything the caller wanted, reset the peek buffer. */ +		bt->peek_buf_len = 0; +		return buflen; +	} +	else +		return bt->peek_buf_len; +} + + +/*  + * This function is scheduled in bs_handshake via b_timeout_add after a (non-blocking) connect(). + */ +gboolean jabber_bs_connect_timeout( gpointer data, gint fd, b_input_condition cond ) +{ +	struct bs_transfer *bt = data; + +	bt->connect_timeout = 0; + +	jabber_bs_abort( bt, "no connection after %d seconds", bt->tf->ft->sending ? JABBER_BS_LISTEN_TIMEOUT : JABBER_BS_CONTIMEOUT ); + +	return FALSE; +} + +/*  + * Polls the socket, checks for errors and removes a connect timer + * if there is one. + */ +gboolean jabber_bs_poll( struct bs_transfer *bt, int fd, short *revents ) +{ +	struct pollfd pfd = { .fd = fd, .events = POLLHUP|POLLERR }; +	 +	if ( bt->connect_timeout ) +	{ +		b_event_remove( bt->connect_timeout ); +		bt->connect_timeout = 0; +	} + +	ASSERTSOCKOP( poll( &pfd, 1, 0 ), "poll()" ) + +	if( pfd.revents & POLLERR ) +	{ +		int sockerror; +		socklen_t errlen = sizeof( sockerror ); + +		if ( getsockopt( fd, SOL_SOCKET, SO_ERROR, &sockerror, &errlen ) ) +			return jabber_bs_abort( bt, "getsockopt() failed, unknown socket error during SOCKS5 handshake (weird!)" ); + +		if ( bt->phase == BS_PHASE_CONNECTED ) +			return jabber_bs_abort( bt, "connect failed: %s", strerror( sockerror ) ); + +		return jabber_bs_abort( bt, "Socket error during SOCKS5 handshake(weird!): %s", strerror( sockerror ) ); +	} + +	if( pfd.revents & POLLHUP ) +		return jabber_bs_abort( bt, "Remote end closed connection" ); +	 +	*revents = pfd.revents; +	 +	return TRUE; +} + +/* + * Used for receive and send path. + */ +gboolean jabber_bs_abort( struct bs_transfer *bt, char *format, ... ) +{ +	va_list params; +	va_start( params, format ); +	char error[128]; + +	if( vsnprintf( error, 128, format, params ) < 0 ) +		sprintf( error, "internal error parsing error string (BUG)" ); +	va_end( params ); +	if( bt->tf->ft->sending ) +		return jabber_bs_send_handshake_abort( bt, error ); +	else +		return jabber_bs_recv_handshake_abort( bt, error ); +} + +/* Bad luck */ +void jabber_bs_canceled( file_transfer_t *ft , char *reason ) +{ +	struct jabber_transfer *tf = ft->data; + +	imcb_log( tf->ic, "File transfer aborted: %s", reason ); +} + +/* + * Parses an incoming bytestream request and calls jabber_bs_handshake on success. + */ +int jabber_bs_recv_request( struct im_connection *ic, struct xt_node *node, struct xt_node *qnode) +{ +	char *sid, *ini_jid, *tgt_jid, *mode, *iq_id; +	struct jabber_data *jd = ic->proto_data; +	struct jabber_transfer *tf = NULL; +	GSList *tflist; +	struct bs_transfer *bt; +	GSList *shlist=NULL; +	struct xt_node *shnode; + +	sha1_state_t sha; +	char hash_hex[41]; +	unsigned char hash[20]; +	int i; +	 +	if( !(iq_id   = xt_find_attr( node, "id" ) ) || +	    !(ini_jid = xt_find_attr( node, "from" ) ) || +	    !(tgt_jid = xt_find_attr( node, "to" ) ) || +	    !(sid     = xt_find_attr( qnode, "sid" ) ) ) +	{ +		imcb_log( ic, "WARNING: Received incomplete SI bytestream request"); +		return XT_HANDLED; +	} + +	if( ( mode = xt_find_attr( qnode, "mode" ) ) && +	      ( strcmp( mode, "tcp" ) != 0 ) )  +	{ +		imcb_log( ic, "WARNING: Received SI Request for unsupported bytestream mode %s", xt_find_attr( qnode, "mode" ) ); +		return XT_HANDLED; +	} + +	shnode = qnode->children; +	while( ( shnode = xt_find_node( shnode, "streamhost" ) ) ) +	{ +		char *jid, *host, *port_s; +		int port; +		if( ( jid = xt_find_attr( shnode, "jid" ) ) && +		    ( host = xt_find_attr( shnode, "host" ) ) && +		    ( port_s = xt_find_attr( shnode, "port" ) ) && +		    ( sscanf( port_s, "%d", &port ) == 1 ) ) +		{ +			jabber_streamhost_t *sh = g_new0( jabber_streamhost_t, 1 ); +			sh->jid = g_strdup(jid); +			sh->host = g_strdup(host); +			sprintf( sh->port, "%u", port ); +			shlist = g_slist_append( shlist, sh ); +		} +		shnode = shnode->next; +	} +	 +	if( !shlist ) +	{ +		imcb_log( ic, "WARNING: Received incomplete SI bytestream request, no parseable streamhost entries"); +		return XT_HANDLED; +	} + +	/* Let's see if we can find out what this bytestream should be for... */ + +	for( tflist = jd->filetransfers ; tflist; tflist = g_slist_next(tflist) ) +	{ +		struct jabber_transfer *tft = tflist->data; +		if( ( strcmp( tft->sid, sid ) == 0 ) && +		    ( strcmp( tft->ini_jid, ini_jid ) == 0 ) && +		    ( strcmp( tft->tgt_jid, tgt_jid ) == 0 ) ) +		{ +		    	tf = tft; +			break; +		} +	} + +	if (!tf)  +	{ +		imcb_log( ic, "WARNING: Received bytestream request from %s that doesn't match an SI request", ini_jid ); +		return XT_HANDLED; +	} + +	/* iq_id and canceled can be reused since SI is done */ +	g_free( tf->iq_id ); +	tf->iq_id = g_strdup( iq_id ); + +	tf->ft->canceled = jabber_bs_canceled; + +	/* SHA1( SID + Initiator JID + Target JID ) is given to the streamhost which it will match against the initiator's value */ +	sha1_init( &sha ); +	sha1_append( &sha, (unsigned char*) sid, strlen( sid ) ); +	sha1_append( &sha, (unsigned char*) ini_jid, strlen( ini_jid ) ); +	sha1_append( &sha, (unsigned char*) tgt_jid, strlen( tgt_jid ) ); +	sha1_finish( &sha, hash ); +	 +	for( i = 0; i < 20; i ++ ) +		sprintf( hash_hex + i * 2, "%02x", hash[i] ); +		 +	bt = g_new0( struct bs_transfer, 1 ); +	bt->tf = tf; +	bt->streamhosts = shlist; +	bt->sh = shlist->data; +	bt->phase = BS_PHASE_CONNECT; +	bt->pseudoadr = g_strdup( hash_hex ); +	tf->streamhandle = bt; +	tf->ft->free = jabber_bs_free_transfer; + +	jabber_bs_recv_handshake( bt, -1, 0 );  + +	return XT_HANDLED; +} + +/* + * This is what a protocol handshake can look like in cooperative multitasking :) + * Might be confusing at first because it's called from different places and is recursing. + * (places being the event thread, bs_request, bs_handshake_abort, and itself) + * + * All in all, it turned out quite nice :) + */ +gboolean jabber_bs_recv_handshake( gpointer data, gint fd, b_input_condition cond ) +{ + +	struct bs_transfer *bt = data; +	short revents; +	int gret; + +	if ( ( fd != -1 ) && !jabber_bs_poll( bt, fd, &revents ) ) +		return FALSE; +	 +	switch( bt->phase )  +	{ +	case BS_PHASE_CONNECT: +		{ +			struct addrinfo hints, *rp; + +			memset( &hints, 0, sizeof( struct addrinfo ) ); +			hints.ai_socktype = SOCK_STREAM; + +			if ( ( gret = getaddrinfo( bt->sh->host, bt->sh->port, &hints, &rp ) ) != 0 ) +				return jabber_bs_abort( bt, "getaddrinfo() failed: %s", gai_strerror( gret ) ); + +			ASSERTSOCKOP( bt->tf->fd = fd = socket( rp->ai_family, rp->ai_socktype, 0 ), "Opening socket" ); + +			sock_make_nonblocking( fd ); + +			imcb_log( bt->tf->ic, "File %s: Connecting to streamhost %s:%s", bt->tf->ft->file_name, bt->sh->host, bt->sh->port ); + +			if( ( connect( fd, rp->ai_addr, rp->ai_addrlen ) == -1 ) && +			    ( errno != EINPROGRESS ) ) +				return jabber_bs_abort( bt , "connect() failed: %s", strerror( errno ) ); + +			freeaddrinfo( rp ); + +			bt->phase = BS_PHASE_CONNECTED; +			 +			bt->tf->watch_out = b_input_add( fd, GAIM_INPUT_WRITE, jabber_bs_recv_handshake, bt ); + +			/* since it takes forever(3mins?) till connect() fails on itself we schedule a timeout */ +			bt->connect_timeout = b_timeout_add( JABBER_BS_CONTIMEOUT * 1000, jabber_bs_connect_timeout, bt ); + +			bt->tf->watch_in = 0; +			return FALSE; +		} +	case BS_PHASE_CONNECTED: +		{ +			struct { +				unsigned char ver; +				unsigned char nmethods; +				unsigned char method; +			} socks5_hello = { +				.ver = 5, +				.nmethods = 1, +				.method = 0x00 /* no auth */ +				/* one could also implement username/password. If you know +				 * a jabber client or proxy that actually does it, tell me. +				 */ +			}; +			 +			ASSERTSOCKOP( send( fd, &socks5_hello, sizeof( socks5_hello ) , 0 ), "Sending auth request" ); + +			bt->phase = BS_PHASE_REQUEST; + +			bt->tf->watch_in = b_input_add( fd, GAIM_INPUT_READ, jabber_bs_recv_handshake, bt ); + +			bt->tf->watch_out = 0; +			return FALSE; +		} +	case BS_PHASE_REQUEST: +		{ +			struct socks5_message socks5_connect =  +			{ +				.ver = 5, +				.cmdrep.cmd = 0x01, +				.rsv = 0, +				.atyp = 0x03, +				.addrlen = strlen( bt->pseudoadr ), +				.port = 0 +			}; +			int ret; +			char buf[2]; + +			/* If someone's trying to be funny and sends only one byte at a time we'll fail :) */ +			ASSERTSOCKOP( ret = recv( fd, buf, 2, 0 ) , "Receiving auth reply" ); + +			if( !( ret == 2 ) || +			    !( buf[0] == 5 ) || +			    !( buf[1] == 0 ) ) +				return jabber_bs_abort( bt, "Auth not accepted by streamhost (reply: len=%d, ver=%d, status=%d)", +									ret, buf[0], buf[1] ); + +			/* copy hash into connect message */ +			memcpy( socks5_connect.address, bt->pseudoadr, socks5_connect.addrlen ); + +			ASSERTSOCKOP( send( fd, &socks5_connect, sizeof( struct socks5_message ), 0 ) , "Sending SOCKS5 Connect" ); + +			bt->phase = BS_PHASE_REPLY; + +			return TRUE; +		} +	case BS_PHASE_REPLY: +		{ +			struct socks5_message socks5_reply; +			int ret; + +			if ( !( ret = jabber_bs_peek( bt, &socks5_reply, sizeof( struct socks5_message ) ) ) ) +				return FALSE; + +			if ( ret < 5 ) /* header up to address length */ +				return TRUE; +			else if( ret < sizeof( struct socks5_message ) ) +			{ +				/* Either a buggy proxy or just one that doesnt regard the SHOULD in XEP-0065 +				 * saying the reply SHOULD contain the address */ + +				ASSERTSOCKOP( ret = recv( fd, &socks5_reply, ret, 0 ), "Dequeuing after MSG_PEEK" ); +			} + +			if( !( socks5_reply.ver == 5 ) || +			    !( socks5_reply.cmdrep.rep == 0 ) ) { +			    	char errstr[128] = ""; +				if( ( socks5_reply.ver == 5 ) && ( socks5_reply.cmdrep.rep <  +				    ( sizeof( socks5_reply_code ) / sizeof( socks5_reply_code[0] ) ) ) ) { +					sprintf( errstr, "with \"%s\" ", socks5_reply_code[ socks5_reply.cmdrep.rep ] ); +				} +				return jabber_bs_abort( bt, "SOCKS5 CONNECT failed %s(reply: ver=%d, rep=%d, atyp=%d, addrlen=%d)",  +					errstr, +					socks5_reply.ver, +					socks5_reply.cmdrep.rep, +					socks5_reply.atyp, +					socks5_reply.addrlen); +			} +			 +			/* usually a proxy sends back the 40 bytes address but I encountered at least one (of jabber.cz)  +			 * that sends atyp=0 addrlen=0 and only 6 bytes (one less than one would expect). +			 * Therefore I removed the wait for more bytes. Since we don't care about what else the proxy +			 * is sending, it shouldnt matter */ + +			if( bt->tf->ft->sending ) +				jabber_bs_send_activate( bt ); +			else +				jabber_bs_recv_answer_request( bt ); + +			return FALSE; +		} +	default: +		/* BUG */ +		imcb_log( bt->tf->ic, "BUG in file transfer code: undefined handshake phase" ); + +		bt->tf->watch_in = 0; +		return FALSE; +	} +} + +/* + * If the handshake failed we can try the next streamhost, if there is one. + * An intelligent sender would probably specify himself as the first streamhost and + * a proxy as the second (Kopete and PSI are examples here). That way, a (potentially)  + * slow proxy is only used if neccessary. This of course also means, that the timeout + * per streamhost should be kept short. If one or two firewalled adresses are specified, + * they have to timeout first before a proxy is tried. + */ +gboolean jabber_bs_recv_handshake_abort( struct bs_transfer *bt, char *error ) +{ +	struct jabber_transfer *tf = bt->tf; +	struct xt_node *reply, *iqnode; +	GSList *shlist; + +	imcb_log( tf->ic, "Transferring file %s: connection to streamhost %s:%s failed (%s)",  +		  tf->ft->file_name,  +		  bt->sh->host, +		  bt->sh->port, +		  error ); + +	/* Alright, this streamhost failed, let's try the next... */ +	bt->phase = BS_PHASE_CONNECT; +	shlist = g_slist_find( bt->streamhosts, bt->sh ); +	if( shlist && shlist->next ) +	{ +		bt->sh = shlist->next->data; +		return jabber_bs_recv_handshake( bt, -1, 0 ); +	} + + +	/* out of stream hosts */ + +	iqnode = jabber_make_packet( "iq", "result", tf->ini_jid, NULL ); +	reply = jabber_make_error_packet( iqnode, "item-not-found", "cancel" , "404" ); +	xt_free_node( iqnode ); + +	xt_add_attr( reply, "id", tf->iq_id ); +		 +	if( !jabber_write_packet( tf->ic, reply ) ) +		imcb_log( tf->ic, "WARNING: Error transmitting bytestream response" ); +	xt_free_node( reply ); + +	imcb_file_canceled( tf->ft, "couldn't connect to any streamhosts" ); + +	bt->tf->watch_in = 0; +	/* MUST always return FALSE! */ +	return FALSE; +} + +/*  + * After the SOCKS5 handshake succeeds we need to inform the initiator which streamhost we chose. + * If he is the streamhost himself, he might already know that. However, if it's a proxy, + * the initiator will have to make a connection himself. + */ +void jabber_bs_recv_answer_request( struct bs_transfer *bt ) +{ +	struct jabber_transfer *tf = bt->tf; +	struct xt_node *reply; + +	imcb_log( tf->ic, "File %s: established SOCKS5 connection to %s:%s",  +		  tf->ft->file_name,  +		  bt->sh->host, +		  bt->sh->port ); + +	tf->ft->data = tf; +	tf->watch_in = b_input_add( tf->fd, GAIM_INPUT_READ, jabber_bs_recv_read, bt ); +	tf->ft->write_request = jabber_bs_recv_write_request; + +	reply = xt_new_node( "streamhost-used", NULL, NULL ); +	xt_add_attr( reply, "jid", bt->sh->jid ); + +	reply = xt_new_node( "query", NULL, reply ); +	xt_add_attr( reply, "xmlns", XMLNS_BYTESTREAMS ); + +	reply = jabber_make_packet( "iq", "result", tf->ini_jid, reply ); + +	xt_add_attr( reply, "id", tf->iq_id ); +		 +	if( !jabber_write_packet( tf->ic, reply ) ) +		imcb_file_canceled( tf->ft, "Error transmitting bytestream response" ); +	xt_free_node( reply ); +} + +/*  + * This function is called from write_request directly. If no data is available, it will install itself + * as a watcher for input on fd and once that happens, deliver the data and unschedule itself again. + */ +gboolean jabber_bs_recv_read( gpointer data, gint fd, b_input_condition cond ) +{ +	int ret; +	struct bs_transfer *bt = data; +	struct jabber_transfer *tf = bt->tf; + +	if( fd != -1 ) /* called via event thread */ +	{ +		tf->watch_in = 0; +		ASSERTSOCKOP( ret = recv( fd, tf->ft->buffer, sizeof( tf->ft->buffer ), 0 ) , "Receiving" ); +	} +	else +	{ +		/* called directly. There might not be any data available. */ +		if( ( ( ret = recv( tf->fd, tf->ft->buffer, sizeof( tf->ft->buffer ), 0 ) ) == -1 ) && +		    ( errno != EAGAIN ) ) +		    return jabber_bs_abort( bt, "Receiving: %s", strerror( errno ) ); + +		if( ( ret == -1 ) && ( errno == EAGAIN ) ) +		{ +			tf->watch_in = b_input_add( tf->fd, GAIM_INPUT_READ, jabber_bs_recv_read, bt ); +			return FALSE; +		} +	} + +	/* shouldn't happen since we know the file size */ +	if( ret == 0 ) +		return jabber_bs_abort( bt, "Remote end closed connection" ); +	 +	tf->bytesread += ret; + +	if( tf->bytesread >= tf->ft->file_size ) +		imcb_file_finished( tf->ft ); + +	tf->ft->write( tf->ft, tf->ft->buffer, ret );	 + +	return FALSE; +} + +/*  + * imc callback that is invoked when it is ready to receive some data. + */ +gboolean jabber_bs_recv_write_request( file_transfer_t *ft ) +{ +	struct jabber_transfer *tf = ft->data; + +	if( tf->watch_in ) +	{ +		imcb_file_canceled( ft, "BUG in jabber file transfer: write_request called when already watching for input" ); +		return FALSE; +	} +	 +	jabber_bs_recv_read( tf->streamhandle, -1 , 0 ); + +	return TRUE; +} + +/*  + * Issues a write_request to imc. + * */ +gboolean jabber_bs_send_can_write( gpointer data, gint fd, b_input_condition cond ) +{ +	struct bs_transfer *bt = data; + +	bt->tf->watch_out = 0; + +	bt->tf->ft->write_request( bt->tf->ft ); + +	return FALSE; +} + +/* + * This should only be called if we can write, so just do it. + * Add a write watch so we can write more during the next cycle (if possible). + */ +gboolean jabber_bs_send_write( file_transfer_t *ft, char *buffer, unsigned int len ) +{ +	struct jabber_transfer *tf = ft->data; +	struct bs_transfer *bt = tf->streamhandle; +	int ret; + +	if( tf->watch_out ) +		return jabber_bs_abort( bt, "BUG: write() called while watching " ); +	 +	/* TODO: catch broken pipe */ +	ASSERTSOCKOP( ret = send( tf->fd, buffer, len, 0 ), "Sending" ); + +	tf->byteswritten += ret; +	 +	/* TODO: this should really not be fatal */ +	if( ret < len ) +		return jabber_bs_abort( bt, "send() sent %d instead of %d (send buffer too big!)", ret, len ); + +	if( tf->byteswritten >= ft->file_size ) +		imcb_file_finished( ft ); +	else +		bt->tf->watch_out = b_input_add( tf->fd, GAIM_INPUT_WRITE, jabber_bs_send_can_write, bt ); +		 +	return TRUE; +} + +/* + * Handles the reply by the receiver containing the used streamhost. + */ +static xt_status jabber_bs_send_handle_reply(struct im_connection *ic, struct xt_node *node, struct xt_node *orig ) { +	struct jabber_transfer *tf = NULL; +	struct jabber_data *jd = ic->proto_data; +	struct bs_transfer *bt; +	GSList *tflist; +	struct xt_node *c; +	char *sid, *jid; + +	if( !( c = xt_find_node( node->children, "query" ) ) || +	    !( c = xt_find_node( c->children, "streamhost-used" ) ) || +	    !( jid = xt_find_attr( c, "jid" ) ) ) + +	{ +		imcb_log( ic, "WARNING: Received incomplete bytestream reply" ); +		return XT_HANDLED; +	} +	 +	if( !( c = xt_find_node( orig->children, "query" ) ) || +	    !( sid = xt_find_attr( c, "sid" ) ) ) +	{ +		imcb_log( ic, "WARNING: Error parsing request corresponding to the incoming bytestream reply" ); +		return XT_HANDLED; +	} + +	/* Let's see if we can find out what this bytestream should be for... */ + +	for( tflist = jd->filetransfers ; tflist; tflist = g_slist_next(tflist) ) +	{ +		struct jabber_transfer *tft = tflist->data; +		if( ( strcmp( tft->sid, sid ) == 0 ) ) +		{ +		    	tf = tft; +			break; +		} +	} + +	if( !tf ) +	{ +		imcb_log( ic, "WARNING: Received SOCKS5 bytestream reply to unknown request" ); +		return XT_HANDLED; +	} + +	bt = tf->streamhandle; + +	tf->accepted = TRUE; + +	if( strcmp( jid, tf->ini_jid ) == 0 ) +	{ +		/* we're streamhost and target */ +		if( bt->phase == BS_PHASE_REPLY ) +		{ +			/* handshake went through, let's start transferring */ +			tf->ft->write_request( tf->ft ); +		} +	} else +	{ +		/* using a proxy, abort listen */ + +		if( tf->watch_in ) +		{ +			b_event_remove( tf->watch_in ); +			tf->watch_in = 0; +		} +		 +		if( tf->fd != -1 ) { +			closesocket( tf->fd ); +			tf->fd = -1; +		} + +		if ( bt->connect_timeout ) +		{ +			b_event_remove( bt->connect_timeout ); +			bt->connect_timeout = 0; +		} + +		GSList *shlist; +		for( shlist = jd->streamhosts ; shlist ; shlist = g_slist_next( shlist ) ) +		{ +			jabber_streamhost_t *sh = shlist->data; +			if( strcmp( sh->jid, jid ) == 0 ) +			{ +				bt->sh = sh; +				jabber_bs_recv_handshake( bt, -1, 0 ); +				return XT_HANDLED; +			} +		} + +		imcb_log( ic, "WARNING: Received SOCKS5 bytestream reply with unknown streamhost %s", jid ); +	} + +	return XT_HANDLED; +} + +/*  + * Tell the proxy to activate the stream. Looks like this: + * + * <iq type=set> + * 	<query xmlns=bs sid=sid> + * 		<activate>tgt_jid</activate> + * 	</query> + * </iq> + */ +void jabber_bs_send_activate( struct bs_transfer *bt ) +{ +	struct xt_node *node; + +	node = xt_new_node( "activate", bt->tf->tgt_jid, NULL ); +	node = xt_new_node( "query", NULL, node ); +	xt_add_attr( node, "xmlns", XMLNS_BYTESTREAMS ); +	xt_add_attr( node, "sid", bt->tf->sid ); +	node = jabber_make_packet( "iq", "set", bt->sh->jid, node ); + +	jabber_cache_add( bt->tf->ic, node, jabber_bs_send_handle_activate ); + +	jabber_write_packet( bt->tf->ic, node ); +} + +/* + * The proxy has activated the bytestream. + * We can finally start pushing some data out. + */ +static xt_status jabber_bs_send_handle_activate( struct im_connection *ic, struct xt_node *node, struct xt_node *orig ) +{ +	char *sid; +	GSList *tflist; +	struct jabber_transfer *tf = NULL; +	struct xt_node *query; +	struct jabber_data *jd = ic->proto_data; + +	query = xt_find_node( orig->children, "query" ); +	sid = xt_find_attr( query, "sid" ); + +	for( tflist = jd->filetransfers ; tflist; tflist = g_slist_next(tflist) ) +	{ +		struct jabber_transfer *tft = tflist->data; +		if( ( strcmp( tft->sid, sid ) == 0 ) ) +		{ +		    	tf = tft; +			break; +		} +	} + +	if( !tf ) +	{ +		imcb_log( ic, "WARNING: Received SOCKS5 bytestream activation for unknown stream" ); +		return XT_HANDLED; +	} + +	imcb_log( tf->ic, "File %s: SOCKS5 handshake and activation successful! Transfer about to start...", tf->ft->file_name ); + +	/* handshake went through, let's start transferring */ +	tf->ft->write_request( tf->ft ); + +	return XT_HANDLED; +} + +jabber_streamhost_t *jabber_si_parse_proxy( struct im_connection *ic, char *proxy ) +{ +	char *host, *port, *jid; +	jabber_streamhost_t *sh; + +	if( ( ( host = strchr( proxy, ',' ) ) == 0 ) || +	     ( ( port = strchr( host+1, ',' ) ) == 0 ) ) { +		imcb_log( ic, "Error parsing proxy setting: \"%s\" (ignored)", proxy ); +		return NULL; +	} +	 +	jid = proxy; +	*host++ = '\0'; +	*port++ = '\0'; + +	sh = g_new0( jabber_streamhost_t, 1 ); +	sh->jid = g_strdup( jid ); +	sh->host = g_strdup( host ); +	strcpy( sh->port, port ); + +	return sh; +} + +void jabber_si_set_proxies( struct bs_transfer *bt ) +{ +	struct jabber_transfer *tf = bt->tf; +	struct jabber_data *jd = tf->ic->proto_data; +	char *proxysetting = g_strdup ( set_getstr( &tf->ic->acc->set, "proxy" ) ); +	char *proxy, *next, *errmsg = NULL; +	char port[6]; +	char host[HOST_NAME_MAX+1]; +	jabber_streamhost_t *sh, *sh2; +	GSList *streamhosts = jd->streamhosts; + +	proxy = proxysetting; +	while ( proxy && ( *proxy!='\0' ) ) { +		if( ( next = strchr( proxy, ';' ) ) ) +			*next++ = '\0';	 +		 +		if( strcmp( proxy, "<local>" ) == 0 ) { +			if( ( tf->fd = ft_listen( &tf->saddr, host, port, FALSE, &errmsg ) ) != -1 ) { +				sh = g_new0( jabber_streamhost_t, 1 ); +				sh->jid = g_strdup( tf->ini_jid ); +				sh->host = g_strdup( host ); +				strcpy( sh->port, port ); +				bt->streamhosts = g_slist_append( bt->streamhosts, sh ); + +				bt->tf->watch_in = b_input_add( tf->fd, GAIM_INPUT_READ, jabber_bs_send_handshake, bt ); +				bt->connect_timeout = b_timeout_add( JABBER_BS_LISTEN_TIMEOUT * 1000, jabber_bs_connect_timeout, bt ); +			} else { +				imcb_log( tf->ic, "Transferring file %s: couldn't listen locally(non fatal, check your ft_listen setting in bitlbee.conf): %s", +					  tf->ft->file_name, +					  errmsg ); +			} +		} else if( strcmp( proxy, "<auto>" ) == 0 ) { +			while ( streamhosts ) { +				sh = g_new0( jabber_streamhost_t, 1 ); +				sh2 = streamhosts->data; +				sh->jid = g_strdup( sh2->jid ); +				sh->host = g_strdup( sh2->host ); +				strcpy( sh->port, sh2->port ); +				bt->streamhosts = g_slist_append( bt->streamhosts, sh ); +				streamhosts = g_slist_next( streamhosts ); +			} +		} else if( ( sh = jabber_si_parse_proxy( tf->ic, proxy ) ) ) +			bt->streamhosts = g_slist_append( bt->streamhosts, sh ); +		proxy = next; +	} +} + +/* + * Starts a bytestream. + */ +gboolean jabber_bs_send_start( struct jabber_transfer *tf ) +{ +	struct bs_transfer *bt; +	sha1_state_t sha; +	char hash_hex[41]; +	unsigned char hash[20]; +	int i,ret; + +	/* SHA1( SID + Initiator JID + Target JID ) is given to the streamhost which it will match against the initiator's value */ +	sha1_init( &sha ); +	sha1_append( &sha, (unsigned char*) tf->sid, strlen( tf->sid ) ); +	sha1_append( &sha, (unsigned char*) tf->ini_jid, strlen( tf->ini_jid ) ); +	sha1_append( &sha, (unsigned char*) tf->tgt_jid, strlen( tf->tgt_jid ) ); +	sha1_finish( &sha, hash ); +	 +	for( i = 0; i < 20; i ++ ) +		sprintf( hash_hex + i * 2, "%02x", hash[i] ); +		 +	bt = g_new0( struct bs_transfer, 1 ); +	bt->tf = tf; +	bt->phase = BS_PHASE_CONNECT; +	bt->pseudoadr = g_strdup( hash_hex ); +	tf->streamhandle = bt; +	tf->ft->free = jabber_bs_free_transfer; +	tf->ft->canceled = jabber_bs_canceled; + +	jabber_si_set_proxies( bt ); + +	ret = jabber_bs_send_request( tf, bt->streamhosts); + +	return ret; +} + +gboolean jabber_bs_send_request( struct jabber_transfer *tf, GSList *streamhosts ) +{ +	struct xt_node *shnode, *query, *iq; + +	query = xt_new_node( "query", NULL, NULL ); +	xt_add_attr( query, "xmlns", XMLNS_BYTESTREAMS ); +	xt_add_attr( query, "sid", tf->sid ); +	xt_add_attr( query, "mode", "tcp" ); + +	while( streamhosts ) { +		jabber_streamhost_t *sh = streamhosts->data; +		shnode = xt_new_node( "streamhost", NULL, NULL ); +		xt_add_attr( shnode, "jid", sh->jid ); +		xt_add_attr( shnode, "host", sh->host ); +		xt_add_attr( shnode, "port", sh->port ); + +		xt_add_child( query, shnode ); + +		streamhosts = g_slist_next( streamhosts ); +	} + + +	iq = jabber_make_packet( "iq", "set", tf->tgt_jid, query ); +	xt_add_attr( iq, "from", tf->ini_jid ); + +	jabber_cache_add( tf->ic, iq, jabber_bs_send_handle_reply ); + +	if( !jabber_write_packet( tf->ic, iq ) ) +		imcb_file_canceled( tf->ft, "Error transmitting bytestream request" ); +	return TRUE; +} + +gboolean jabber_bs_send_handshake_abort(struct bs_transfer *bt, char *error ) +{ +	struct jabber_transfer *tf = bt->tf; +	struct jabber_data *jd = tf->ic->proto_data; + +	/* TODO: did the receiver get here somehow??? */ +	imcb_log( tf->ic, "Transferring file %s: SOCKS5 handshake failed: %s",  +		  tf->ft->file_name,  +		  error ); + +	if( jd->streamhosts==NULL ) /* we're done here unless we have a proxy to try */ +		imcb_file_canceled( tf->ft, error ); + +	/* MUST always return FALSE! */ +	return FALSE; +} + +/* + * SOCKS5BYTESTREAM protocol for the sender + */ +gboolean jabber_bs_send_handshake( gpointer data, gint fd, b_input_condition cond ) +{ +	struct bs_transfer *bt = data; +	struct jabber_transfer *tf = bt->tf; +	short revents; + +	if ( !jabber_bs_poll( bt, fd, &revents ) ) +		return FALSE; +	 +	switch( bt->phase )  +	{ +	case BS_PHASE_CONNECT: +		{ +			struct sockaddr_storage clt_addr; +			socklen_t ssize = sizeof( clt_addr ); +			 +			/* Connect */ + +			ASSERTSOCKOP( tf->fd = accept( fd, (struct sockaddr *) &clt_addr, &ssize ), "Accepting connection" ); + +			closesocket( fd ); +			fd = tf->fd; +			sock_make_nonblocking( fd ); +			 +			bt->phase = BS_PHASE_CONNECTED; + +			bt->tf->watch_in = b_input_add( fd, GAIM_INPUT_READ, jabber_bs_send_handshake, bt ); +			return FALSE; +		} +	case BS_PHASE_CONNECTED: +		{ +			int ret, have_noauth=FALSE; +			struct { +				unsigned char ver; +				unsigned char method; +			} socks5_auth_reply = { .ver = 5, .method = 0 }; +			struct { +				unsigned char ver; +				unsigned char nmethods; +				unsigned char method; +			} socks5_hello; + +			if( !( ret = jabber_bs_peek( bt, &socks5_hello, sizeof( socks5_hello ) ) ) ) +				return FALSE; + +			if( ret < sizeof( socks5_hello ) ) +				return TRUE; + +			if( !( socks5_hello.ver == 5 ) || +			    !( socks5_hello.nmethods >= 1 ) || +			    !( socks5_hello.nmethods < 32 ) ) +				return jabber_bs_abort( bt, "Invalid auth request ver=%d nmethods=%d method=%d", socks5_hello.ver, socks5_hello.nmethods, socks5_hello.method ); + +			have_noauth = socks5_hello.method == 0; + +			if( socks5_hello.nmethods > 1 ) +			{ +				char mbuf[32]; +				int i; +				ASSERTSOCKOP( ret = recv( fd, mbuf, socks5_hello.nmethods - 1, 0 ) , "Receiving auth methods" ); +				if( ret < ( socks5_hello.nmethods - 1 ) ) +					return jabber_bs_abort( bt, "Partial auth request"); +				for( i = 0 ; !have_noauth && ( i < socks5_hello.nmethods - 1 ) ; i ++ ) +					if( mbuf[i] == 0 ) +						have_noauth = TRUE; +			} +			 +			if( !have_noauth ) +				return jabber_bs_abort( bt, "Auth request didn't include no authentication" ); + +			ASSERTSOCKOP( send( fd, &socks5_auth_reply, sizeof( socks5_auth_reply ) , 0 ), "Sending auth reply" ); + +			bt->phase = BS_PHASE_REQUEST; + +			return TRUE; +		} +	case BS_PHASE_REQUEST: +		{ +			struct socks5_message socks5_connect; +			int msgsize = sizeof( struct socks5_message ); +			int ret; + +			if( !( ret = jabber_bs_peek( bt, &socks5_connect, msgsize ) ) ) +				return FALSE; + +			if( ret < msgsize ) +				return TRUE; + +			if( !( socks5_connect.ver == 5) || +			    !( socks5_connect.cmdrep.cmd == 1 ) || +			    !( socks5_connect.atyp == 3 ) || +			    !(socks5_connect.addrlen == 40 ) ) +				return jabber_bs_abort( bt, "Invalid SOCKS5 Connect message (addrlen=%d, ver=%d, cmd=%d, atyp=%d)", socks5_connect.addrlen, socks5_connect.ver, socks5_connect.cmdrep.cmd, socks5_connect.atyp ); +			if( !( memcmp( socks5_connect.address, bt->pseudoadr, 40 ) == 0 ) ) +				return jabber_bs_abort( bt, "SOCKS5 Connect message contained wrong digest"); + +			socks5_connect.cmdrep.rep = 0; + +			ASSERTSOCKOP( send( fd, &socks5_connect, msgsize, 0 ), "Sending connect reply" ); + +			bt->phase = BS_PHASE_REPLY; + +			imcb_log( tf->ic, "File %s: SOCKS5 handshake successful! Transfer about to start...", tf->ft->file_name ); + +			if( tf->accepted ) +			{ +				/* streamhost-used message came already in(possible?), let's start sending */ +				tf->ft->write_request( tf->ft ); +			} + +			tf->watch_in = 0; +			return FALSE; + +		} +	default: +		/* BUG */ +		imcb_log( bt->tf->ic, "BUG in file transfer code: undefined handshake phase" ); + +		bt->tf->watch_in = 0; +		return FALSE; +	} +} +#undef ASSERTSOCKOP | 
