Merging in file transfer support. Most important points from my review

are fixed now, time to let it settle in and get people to try it.

1 files changed, 638 insertions, 0 deletions

diff --git a/dcc.c b/dcc.c
new file mode 100644
index 00000000..558d923a
--- /dev/null
+++ b/dcc.c
@@ -0,0 +1,638 @@
+/********************************************************************\
+* 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;
+
+static void dcc_finish( file_transfer_t *file );
+static 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, char *user_nick, struct sockaddr_storage *saddr );
+gboolean dccs_recv_start( file_transfer_t *ft );
+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, ... );
+
+/* As defined in ft.h */
+file_transfer_t *imcb_file_send_start( struct im_connection *ic, char *handle, char *file_name, size_t file_size )
+{
+	user_t *u = user_findhandle( ic, handle );
+	/* one could handle this more intelligent like imcb_buddy_msg.
+	 * can't call it directly though cause it does some wrapping.
+	 * Maybe give imcb_buddy_msg a parameter NO_WRAPPING? */
+	if (!u) return NULL;
+
+	return dccs_send_start( ic, u->nick, file_name, file_size );
+};
+
+/* As defined in ft.h */
+void imcb_file_canceled( file_transfer_t *file, char *reason )
+{
+	if( file->canceled )
+		file->canceled( file, reason );
+
+	dcc_close( file );
+}
+
+/* As defined in ft.h */
+gboolean imcb_file_recv_start( file_transfer_t *ft )
+{
+	return dccs_recv_start( ft );
+}
+
+/* As defined in ft.h */
+void imcb_file_finished( file_transfer_t *file )
+{
+	dcc_file_transfer_t *df = file->priv;
+
+	if( file->bytes_transferred >= file->file_size )
+		dcc_finish( file );
+	else
+		df->proto_finished = TRUE;
+}
+
+dcc_file_transfer_t *dcc_alloc_transfer( 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++;
+	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, char *user_nick, char *file_name, size_t file_size )
+{
+	file_transfer_t *file;
+	dcc_file_transfer_t *df;
+	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, user_nick, &saddr ) )
+		return NULL;
+
+	/* watch */
+	df->watch_in = b_input_add( df->fd, GAIM_INPUT_READ, dccs_send_proto, df );
+
+	df->ic->irc->file_transfers = g_slist_prepend( df->ic->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 'transfers reject' command.",
+	              user_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, char *user_nick, 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 );
+	
+	if ( !irc_msgfrom( df->ic->irc, user_nick, cmd ) )
+		return dcc_abort( df, "Couldn't send `DCC SEND' message to %s.", user_nick );
+
+	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 & GAIM_INPUT_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, GAIM_INPUT_READ, dccs_send_proto, df );
+
+		return FALSE;
+	}
+
+	if( cond & GAIM_INPUT_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, GAIM_INPUT_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 & GAIM_INPUT_WRITE ) &&
+	    ( ft->status & FT_STATUS_CONNECTING ) )
+	{
+		ft->status = FT_STATUS_TRANSFERRING;
+
+		//df->watch_in = b_input_add( df->fd, GAIM_INPUT_READ, dccs_recv_proto, df );
+
+		df->watch_out = 0;
+		return FALSE;
+	}
+
+	if( cond & GAIM_INPUT_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, GAIM_INPUT_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, GAIM_INPUT_WRITE, dccs_send_can_write, df );
+
+	return TRUE;
+}
+
+/*
+ * Cleans up after a transfer.
+ */
+static void dcc_close( file_transfer_t *file )
+{
+	dcc_file_transfer_t *df = file->priv;
+
+	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 );
+	
+	df->ic->irc->file_transfers = g_slist_remove( df->ic->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 *line )
+{
+	char *pattern = "SEND"
+		" (([^\"][^ ]*)|\"(([^\"]|\\\")*)\")"
+		" (([0-9]*)|([^ ]*))"
+		" ([0-9]*)"
+		" ([0-9]*)\001";
+	regmatch_t pmatch[10];
+	regex_t re;
+	file_transfer_t *ft;
+	dcc_file_transfer_t *df;
+	char errbuf[256];
+	int regerrcode, gret;
+
+	if( ( regerrcode = regcomp( &re, pattern, REG_EXTENDED ) ) ||
+	    ( regerrcode = regexec( &re, line, 10, pmatch, 0 ) ) ) {
+		regerror( regerrcode,&re,errbuf,sizeof( errbuf ) );
+		imcb_log( ic, 
+			  "DCC: error parsing 'DCC SEND': %s, line: %s", 
+			  errbuf, line );
+		return NULL;
+	}
+
+	if( ( pmatch[1].rm_so > 0 ) &&
+	    ( pmatch[5].rm_so > 0 ) &&
+	    ( pmatch[8].rm_so > 0 ) &&
+	    ( pmatch[9].rm_so > 0 ) )
+	{
+		char *input = g_strdup( line );
+		char *filename, *host, *port;
+		size_t filesize;
+		struct addrinfo hints, *rp;
+
+		/* "filename" or filename */
+		if ( pmatch[2].rm_so > 0 )
+		{
+			input[pmatch[2].rm_eo] = '\0';
+			filename = input + pmatch[2].rm_so;
+		} else
+		{
+			input[pmatch[3].rm_eo] = '\0';
+			filename = input + pmatch[3].rm_so;
+		}
+			
+		input[pmatch[5].rm_eo] = '\0';
+
+		/* number means ipv4, something else means ipv6 */
+		if ( pmatch[6].rm_so > 0 )
+		{
+			struct in_addr ipaddr = { .s_addr = htonl( strtoul( input + pmatch[5].rm_so, NULL, 10 ) ) };
+			host = inet_ntoa( ipaddr );
+		} else
+		{
+			/* Contains non-numbers, hopefully an IPV6 address */
+			host = input + pmatch[7].rm_so;
+		}
+
+		input[pmatch[8].rm_eo] = '\0';
+		input[pmatch[9].rm_eo] = '\0';
+
+		port = input + pmatch[8].rm_so;
+		filesize = atoll( input + pmatch[9].rm_so );
+
+		memset( &hints, 0, sizeof ( struct addrinfo ) );
+		hints.ai_socktype = SOCK_STREAM;
+		hints.ai_flags = AI_NUMERICSERV;
+
+		if ( ( gret = getaddrinfo( host, port, &hints, &rp ) ) )
+		{
+			g_free( input );
+			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 );
+		g_free( input );
+
+		df->ic->irc->file_transfers = g_slist_prepend( df->ic->irc->file_transfers, ft );
+
+		return ft;
+	}
+
+	imcb_log( ic, "DCC: couldnt parse 'DCC SEND' line: %s", line );
+
+	return NULL;
+}
+