diff options
Diffstat (limited to 'protocols/jabber/s5bytestream.c')
| -rw-r--r-- | protocols/jabber/s5bytestream.c | 1141 |
1 files changed, 1141 insertions, 0 deletions
diff --git a/protocols/jabber/s5bytestream.c b/protocols/jabber/s5bytestream.c new file mode 100644 index 00000000..3c5ce503 --- /dev/null +++ b/protocols/jabber/s5bytestream.c @@ -0,0 +1,1141 @@ +/***************************************************************************\ +* * +* 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; +}; + +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; + + ASSERTSOCKOP( ret = recv( fd, buffer, buflen, MSG_PEEK ), "MSG_PEEK'ing" ); + + if( ret == 0 ) + return jabber_bs_abort( bt, "Remote end closed connection" ); + + if( ret < buflen ) + return ret; + + ASSERTSOCKOP( ret = recv( fd, buffer, buflen, 0 ), "Dequeuing after MSG_PEEK" ); + + if( ret != buflen ) + return jabber_bs_abort( bt, "recv returned less than previous recv with MSG_PEEK" ); + + return ret; +} + + +/* + * 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; + int port; + if( ( jid = xt_find_attr( shnode, "jid" ) ) && + ( host = xt_find_attr( shnode, "host" ) ) && + ( ( port = atoi( xt_find_attr( shnode, "port" ) ) ) ) ) + { + 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; + 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; + 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[INET6_ADDRSTRLEN]; + 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 ); + + 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 |