diff options
Diffstat (limited to 'dcc.c')
-rw-r--r-- | dcc.c | 566 |
1 files changed, 566 insertions, 0 deletions
@@ -0,0 +1,566 @@ +/********************************************************************\ +* BitlBee -- An IRC to other IM-networks gateway * +* * +* 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 with + the Debian GNU/Linux distribution in /usr/share/common-licenses/GPL; + if not, write to the Free Software Foundation, Inc., 59 Temple Place, + Suite 330, Boston, MA 02111-1307 USA +*/ + +#define BITLBEE_CORE +#include "bitlbee.h" +#include "ft.h" +#include "dcc.h" +#include <netinet/tcp.h> +#include <regex.h> +#include "lib/ftutil.h" + +/* + * Since that might be confusing a note on naming: + * + * Generic dcc functions start with + * + * dcc_ + * + * ,methods specific to DCC SEND start with + * + * dccs_ + * + * . Since we can be on both ends of a DCC SEND, + * functions specific to one end are called + * + * dccs_send and dccs_recv + * + * ,respectively. + */ + + +/* + * used to generate a unique local transfer id the user + * can use to reject/cancel transfers + */ +unsigned int local_transfer_id=1; + +/* + * just for debugging the nr. of chunks we received from im-protocols and the total data + */ +unsigned int receivedchunks=0, receiveddata=0; + +void dcc_finish( file_transfer_t *file ); +void dcc_close( file_transfer_t *file ); +gboolean dccs_send_proto( gpointer data, gint fd, b_input_condition cond ); +int dccs_send_request( struct dcc_file_transfer *df, irc_user_t *iu, struct sockaddr_storage *saddr ); +gboolean dccs_recv_proto( gpointer data, gint fd, b_input_condition cond); +gboolean dccs_recv_write_request( file_transfer_t *ft ); +gboolean dcc_progress( gpointer data, gint fd, b_input_condition cond ); +gboolean dcc_abort( dcc_file_transfer_t *df, char *reason, ... ); + +dcc_file_transfer_t *dcc_alloc_transfer( const char *file_name, size_t file_size, struct im_connection *ic ) +{ + file_transfer_t *file = g_new0( file_transfer_t, 1 ); + dcc_file_transfer_t *df = file->priv = g_new0( dcc_file_transfer_t, 1 ); + + file->file_size = file_size; + file->file_name = g_strdup( file_name ); + file->local_id = local_transfer_id++; + file->ic = df->ic = ic; + df->ft = file; + + return df; +} + +/* This is where the sending magic starts... */ +file_transfer_t *dccs_send_start( struct im_connection *ic, irc_user_t *iu, const char *file_name, size_t file_size ) +{ + file_transfer_t *file; + dcc_file_transfer_t *df; + irc_t *irc = (irc_t *) ic->bee->ui_data; + struct sockaddr_storage saddr; + char *errmsg; + char host[HOST_NAME_MAX]; + char port[6]; + + if( file_size > global.conf->ft_max_size ) + return NULL; + + df = dcc_alloc_transfer( file_name, file_size, ic ); + file = df->ft; + file->write = dccs_send_write; + + /* listen and request */ + + if( ( df->fd = ft_listen( &saddr, host, port, TRUE, &errmsg ) ) == -1 ) + { + dcc_abort( df, "Failed to listen locally, check your ft_listen setting in bitlbee.conf: %s", errmsg ); + return NULL; + } + + file->status = FT_STATUS_LISTENING; + + if( !dccs_send_request( df, iu, &saddr ) ) + return NULL; + + /* watch */ + df->watch_in = b_input_add( df->fd, B_EV_IO_READ, dccs_send_proto, df ); + + irc->file_transfers = g_slist_prepend( irc->file_transfers, file ); + + df->progress_timeout = b_timeout_add( DCC_MAX_STALL * 1000, dcc_progress, df ); + + imcb_log( ic, "File transfer request from %s for %s (%zd kb).\n" + "Accept the file transfer if you'd like the file. If you don't, " + "issue the 'transfer reject' command.", + iu->nick, file_name, file_size / 1024 ); + + return file; +} + +/* Used pretty much everywhere in the code to abort a transfer */ +gboolean dcc_abort( dcc_file_transfer_t *df, char *reason, ... ) +{ + file_transfer_t *file = df->ft; + va_list params; + va_start( params, reason ); + char *msg = g_strdup_vprintf( reason, params ); + va_end( params ); + + file->status |= FT_STATUS_CANCELED; + + if( file->canceled ) + file->canceled( file, msg ); + + imcb_log( df->ic, "File %s: DCC transfer aborted: %s", file->file_name, msg ); + + g_free( msg ); + + dcc_close( df->ft ); + + return FALSE; +} + +gboolean dcc_progress( gpointer data, gint fd, b_input_condition cond ) +{ + struct dcc_file_transfer *df = data; + + if( df->bytes_sent == df->progress_bytes_last ) + { + /* no progress. cancel */ + if( df->bytes_sent == 0 ) + return dcc_abort( df, "Couldn't establish transfer within %d seconds", DCC_MAX_STALL ); + else + return dcc_abort( df, "Transfer stalled for %d seconds at %d kb", DCC_MAX_STALL, df->bytes_sent / 1024 ); + + } + + df->progress_bytes_last = df->bytes_sent; + + return TRUE; +} + +/* used extensively for socket operations */ +#define ASSERTSOCKOP(op, msg) \ + if( (op) == -1 ) \ + return dcc_abort( df , msg ": %s", strerror( errno ) ); + +/* Creates the "DCC SEND" line and sends it to the server */ +int dccs_send_request( struct dcc_file_transfer *df, irc_user_t *iu, struct sockaddr_storage *saddr ) +{ + char ipaddr[INET6_ADDRSTRLEN]; + const void *netaddr; + int port; + char *cmd; + + if( saddr->ss_family == AF_INET ) + { + struct sockaddr_in *saddr_ipv4 = ( struct sockaddr_in *) saddr; + + sprintf( ipaddr, "%d", + ntohl( saddr_ipv4->sin_addr.s_addr ) ); + port = saddr_ipv4->sin_port; + } + else + { + struct sockaddr_in6 *saddr_ipv6 = ( struct sockaddr_in6 *) saddr; + + netaddr = &saddr_ipv6->sin6_addr.s6_addr; + port = saddr_ipv6->sin6_port; + + /* + * Didn't find docs about this, but it seems that's the way irssi does it + */ + if( !inet_ntop( saddr->ss_family, netaddr, ipaddr, sizeof( ipaddr ) ) ) + return dcc_abort( df, "inet_ntop failed: %s", strerror( errno ) ); + } + + port = ntohs( port ); + + cmd = g_strdup_printf( "\001DCC SEND %s %s %u %zu\001", + df->ft->file_name, ipaddr, port, df->ft->file_size ); + + irc_send_msg_raw( iu, "PRIVMSG", iu->irc->user->nick, cmd ); + + g_free( cmd ); + + return TRUE; +} + +/* + * After setup, the transfer itself is handled entirely by this function. + * There are basically four things to handle: connect, receive, send, and error. + */ +gboolean dccs_send_proto( gpointer data, gint fd, b_input_condition cond ) +{ + dcc_file_transfer_t *df = data; + file_transfer_t *file = df->ft; + + if( ( cond & B_EV_IO_READ ) && + ( file->status & FT_STATUS_LISTENING ) ) + { + struct sockaddr *clt_addr; + socklen_t ssize = sizeof( clt_addr ); + + /* Connect */ + + ASSERTSOCKOP( df->fd = accept( fd, (struct sockaddr *) &clt_addr, &ssize ), "Accepting connection" ); + + closesocket( fd ); + fd = df->fd; + file->status = FT_STATUS_TRANSFERRING; + sock_make_nonblocking( fd ); + + /* IM protocol callback */ + if( file->accept ) + file->accept( file ); + + /* reschedule for reading on new fd */ + df->watch_in = b_input_add( fd, B_EV_IO_READ, dccs_send_proto, df ); + + return FALSE; + } + + if( cond & B_EV_IO_READ ) + { + int ret; + + ASSERTSOCKOP( ret = recv( fd, ( (char*) &df->acked ) + df->acked_len, + sizeof( df->acked ) - df->acked_len, 0 ), "Receiving" ); + + if( ret == 0 ) + return dcc_abort( df, "Remote end closed connection" ); + + /* How likely is it that a 32-bit integer gets split accross + packet boundaries? Chances are rarely 0 so let's be sure. */ + if( ( df->acked_len = ( df->acked_len + ret ) % 4 ) > 0 ) + return TRUE; + + df->acked = ntohl( df->acked ); + + /* If any of this is actually happening, the receiver should buy a new IRC client */ + + if ( df->acked > df->bytes_sent ) + return dcc_abort( df, "Receiver magically received more bytes than sent ( %d > %d ) (BUG at receiver?)", df->acked, df->bytes_sent ); + + if ( df->acked < file->bytes_transferred ) + return dcc_abort( df, "Receiver lost bytes? ( has %d, had %d ) (BUG at receiver?)", df->acked, file->bytes_transferred ); + + file->bytes_transferred = df->acked; + + if( file->bytes_transferred >= file->file_size ) { + if( df->proto_finished ) + dcc_finish( file ); + return FALSE; + } + + return TRUE; + } + + return TRUE; +} + +gboolean dccs_recv_start( file_transfer_t *ft ) +{ + dcc_file_transfer_t *df = ft->priv; + struct sockaddr_storage *saddr = &df->saddr; + int fd; + char ipaddr[INET6_ADDRSTRLEN]; + socklen_t sa_len = saddr->ss_family == AF_INET ? + sizeof( struct sockaddr_in ) : sizeof( struct sockaddr_in6 ); + + if( !ft->write ) + return dcc_abort( df, "BUG: protocol didn't register write()" ); + + ASSERTSOCKOP( fd = df->fd = socket( saddr->ss_family, SOCK_STREAM, 0 ), "Opening Socket" ); + + sock_make_nonblocking( fd ); + + if( ( connect( fd, (struct sockaddr *)saddr, sa_len ) == -1 ) && + ( errno != EINPROGRESS ) ) + return dcc_abort( df, "Connecting to %s:%d : %s", + inet_ntop( saddr->ss_family, + saddr->ss_family == AF_INET ? + ( void* ) &( ( struct sockaddr_in *) saddr )->sin_addr.s_addr : + ( void* ) &( ( struct sockaddr_in6 *) saddr )->sin6_addr.s6_addr, + ipaddr, + sizeof( ipaddr ) ), + ntohs( saddr->ss_family == AF_INET ? + ( ( struct sockaddr_in *) saddr )->sin_port : + ( ( struct sockaddr_in6 *) saddr )->sin6_port ), + strerror( errno ) ); + + ft->status = FT_STATUS_CONNECTING; + + /* watch */ + df->watch_out = b_input_add( df->fd, B_EV_IO_WRITE, dccs_recv_proto, df ); + ft->write_request = dccs_recv_write_request; + + df->progress_timeout = b_timeout_add( DCC_MAX_STALL * 1000, dcc_progress, df ); + + return TRUE; +} + +gboolean dccs_recv_proto( gpointer data, gint fd, b_input_condition cond ) +{ + dcc_file_transfer_t *df = data; + file_transfer_t *ft = df->ft; + + if( ( cond & B_EV_IO_WRITE ) && + ( ft->status & FT_STATUS_CONNECTING ) ) + { + ft->status = FT_STATUS_TRANSFERRING; + + //df->watch_in = b_input_add( df->fd, B_EV_IO_READ, dccs_recv_proto, df ); + + df->watch_out = 0; + return FALSE; + } + + if( cond & B_EV_IO_READ ) + { + int ret, done; + + ASSERTSOCKOP( ret = recv( fd, ft->buffer, sizeof( ft->buffer ), 0 ), "Receiving" ); + + if( ret == 0 ) + return dcc_abort( df, "Remote end closed connection" ); + + if( !ft->write( df->ft, ft->buffer, ret ) ) + return FALSE; + + df->bytes_sent += ret; + + done = df->bytes_sent >= ft->file_size; + + if( ( ( df->bytes_sent - ft->bytes_transferred ) > DCC_PACKET_SIZE ) || + done ) + { + guint32 ack = htonl( ft->bytes_transferred = df->bytes_sent ); + int ackret; + + ASSERTSOCKOP( ackret = send( fd, &ack, 4, 0 ), "Sending DCC ACK" ); + + if ( ackret != 4 ) + return dcc_abort( df, "Error sending DCC ACK, sent %d instead of 4 bytes", ackret ); + } + + if( df->bytes_sent == ret ) + ft->started = time( NULL ); + + if( done ) + { + if( df->watch_out ) + b_event_remove( df->watch_out ); + + if( df->proto_finished ) + dcc_finish( ft ); + + df->watch_in = 0; + return FALSE; + } + + df->watch_in = 0; + return FALSE; + } + + return TRUE; +} + +gboolean dccs_recv_write_request( file_transfer_t *ft ) +{ + dcc_file_transfer_t *df = ft->priv; + + if( df->watch_in ) + return dcc_abort( df, "BUG: write_request() called while watching" ); + + df->watch_in = b_input_add( df->fd, B_EV_IO_READ, dccs_recv_proto, df ); + + return TRUE; +} + +gboolean dccs_send_can_write( gpointer data, gint fd, b_input_condition cond ) +{ + struct dcc_file_transfer *df = data; + df->watch_out = 0; + + df->ft->write_request( df->ft ); + return FALSE; +} + +/* + * Incoming data. + * + */ +gboolean dccs_send_write( file_transfer_t *file, char *data, unsigned int data_len ) +{ + dcc_file_transfer_t *df = file->priv; + int ret; + + receivedchunks++; receiveddata += data_len; + + if( df->watch_out ) + return dcc_abort( df, "BUG: write() called while watching" ); + + ASSERTSOCKOP( ret = send( df->fd, data, data_len, 0 ), "Sending data" ); + + if( ret == 0 ) + return dcc_abort( df, "Remote end closed connection" ); + + /* TODO: this should really not be fatal */ + if( ret < data_len ) + return dcc_abort( df, "send() sent %d instead of %d", ret, data_len ); + + if( df->bytes_sent == 0 ) + file->started = time( NULL ); + + df->bytes_sent += ret; + + if( df->bytes_sent < df->ft->file_size ) + df->watch_out = b_input_add( df->fd, B_EV_IO_WRITE, dccs_send_can_write, df ); + + return TRUE; +} + +/* + * Cleans up after a transfer. + */ +void dcc_close( file_transfer_t *file ) +{ + dcc_file_transfer_t *df = file->priv; + irc_t *irc = (irc_t *) df->ic->bee->ui_data; + + if( file->free ) + file->free( file ); + + closesocket( df->fd ); + + if( df->watch_in ) + b_event_remove( df->watch_in ); + + if( df->watch_out ) + b_event_remove( df->watch_out ); + + if( df->progress_timeout ) + b_event_remove( df->progress_timeout ); + + irc->file_transfers = g_slist_remove( irc->file_transfers, file ); + + g_free( df ); + g_free( file->file_name ); + g_free( file ); +} + +void dcc_finish( file_transfer_t *file ) +{ + dcc_file_transfer_t *df = file->priv; + time_t diff = time( NULL ) - file->started ? : 1; + + file->status |= FT_STATUS_FINISHED; + + if( file->finished ) + file->finished( file ); + + imcb_log( df->ic, "File %s transferred successfully at %d kb/s!" , file->file_name, (int) ( file->bytes_transferred / 1024 / diff ) ); + dcc_close( file ); +} + +/* + * DCC SEND <filename> <IP> <port> <filesize> + * + * filename can be in "" or not. If it is, " can probably be escaped... + * IP can be an unsigned int (IPV4) or something else (IPV6) + * + */ +file_transfer_t *dcc_request( struct im_connection *ic, char* const* ctcp ) +{ + irc_t *irc = (irc_t *) ic->bee->ui_data; + file_transfer_t *ft; + dcc_file_transfer_t *df; + int gret; + size_t filesize; + + if( ctcp[5] != NULL && + sscanf( ctcp[4], "%zd", &filesize ) == 1 && /* Just int. validation. */ + sscanf( ctcp[5], "%zd", &filesize ) == 1 ) + { + char *filename, *host, *port; + struct addrinfo hints, *rp; + + filename = ctcp[2]; + + host = ctcp[3]; + while( *host && isdigit( *host ) ) host++; /* Just digits? */ + if( *host == '\0' ) + { + struct in_addr ipaddr = { .s_addr = htonl( atoll( ctcp[3] ) ) }; + host = inet_ntoa( ipaddr ); + } else + { + /* Contains non-numbers, hopefully an IPV6 address */ + host = ctcp[3]; + } + + port = ctcp[4]; + filesize = atoll( ctcp[5] ); + + memset( &hints, 0, sizeof ( struct addrinfo ) ); + hints.ai_socktype = SOCK_STREAM; + hints.ai_flags = AI_NUMERICSERV; + + if ( ( gret = getaddrinfo( host, port, &hints, &rp ) ) ) + { + imcb_log( ic, "DCC: getaddrinfo() failed with %s " + "when parsing incoming 'DCC SEND': " + "host %s, port %s", + gai_strerror( gret ), host, port ); + return NULL; + } + + df = dcc_alloc_transfer( filename, filesize, ic ); + ft = df->ft; + ft->sending = TRUE; + memcpy( &df->saddr, rp->ai_addr, rp->ai_addrlen ); + + freeaddrinfo( rp ); + + irc->file_transfers = g_slist_prepend( irc->file_transfers, ft ); + + return ft; + } + else + imcb_log( ic, "DCC: couldnt parse `DCC SEND' line" ); + + return NULL; +} |