Added MSN file transfer of type MSNFTP.

Transfer is direct and the sender can not be firewalled.

6 files changed, 797 insertions, 57 deletions

diff --git a/protocols/msn/Makefile b/protocols/msn/Makefile
index 6a588613..dd5d46e2 100644
--- a/protocols/msn/Makefile
+++ b/protocols/msn/Makefile
@@ -9,7 +9,7 @@
 -include ../../Makefile.settings
 
 # [SH] Program variables
-objects = msn.o msn_util.o ns.o passport.o sb.o tables.o
+objects = msn.o msn_util.o ns.o passport.o sb.o tables.o invitation.o
 
 CFLAGS += -Wall
 LFLAGS += -r
diff --git a/protocols/msn/invitation.c b/protocols/msn/invitation.c
new file mode 100644
index 00000000..4e24d54c
--- /dev/null
+++ b/protocols/msn/invitation.c
@@ -0,0 +1,666 @@
+/********************************************************************\
+* BitlBee -- An IRC to other IM-networks gateway                     *
+*                                                                    *
+* Copyright 2008 Uli Meis					     *
+* Copyright 2006 Marijn Kruisselbrink and others                     *
+\********************************************************************/
+
+/* MSN module - File transfer support             */
+
+/*
+ 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
+ */
+
+#include "bitlbee.h"
+#include "invitation.h"
+#include "msn.h"
+
+#ifdef debug
+#undef debug
+#endif
+#define debug(msg...) log_message( LOGLVL_INFO, msg )
+
+static void msn_ftp_free( file_transfer_t *file );
+static void msn_ftpr_accept( file_transfer_t *file );
+static void msn_ftp_finished( file_transfer_t *file );
+static void msn_ftp_canceled( file_transfer_t *file, char *reason );
+static gboolean msn_ftpr_write_request( file_transfer_t *file );
+
+static gboolean msn_ftp_connected( gpointer data, gint fd, b_input_condition cond );
+static gboolean msn_ftp_read( gpointer data, gint fd, b_input_condition cond );
+gboolean msn_ftps_write( file_transfer_t *file, char *buffer, unsigned int len );
+
+/*
+ * Vararg wrapper for imcb_file_canceled().
+ */
+gboolean msn_ftp_abort( file_transfer_t *file, 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 );
+	imcb_file_canceled( file, error );
+	return FALSE;
+}
+
+/* very useful */
+#define ASSERTSOCKOP(op, msg) \
+	if( (op) == -1 ) \
+		return msn_ftp_abort( file , msg ": %s", strerror( errno ) );
+
+/*
+ * Creates a listening socket and returns its address in host, port.
+ */
+gboolean msn_ftp_listen( msn_filetransfer_t *msn_file, char *host, char *port )
+{
+	file_transfer_t *file = msn_file->dcc;
+        int fd,gret;
+        char hostname[ HOST_NAME_MAX + 1 ];
+        struct addrinfo hints, *rp;
+	struct sockaddr_storage saddrst, *saddr = &saddrst;
+        socklen_t ssize = sizeof( struct sockaddr_storage );
+
+        /* won't be long till someone asks for this to be configurable :) */
+
+        ASSERTSOCKOP( gethostname( hostname, sizeof( hostname ) ), "gethostname()" );
+
+        memset( &hints, 0, sizeof( struct addrinfo ) );
+        hints.ai_socktype = SOCK_STREAM;
+        hints.ai_flags = AI_NUMERICSERV;
+
+        if ( ( gret = getaddrinfo( hostname, "0", &hints, &rp ) ) != 0 )
+                return msn_ftp_abort( file, "getaddrinfo() failed: %s", gai_strerror( gret ) );
+
+        memcpy( saddr, rp->ai_addr, rp->ai_addrlen );
+
+        ASSERTSOCKOP( fd = msn_file->fd = socket( saddr->ss_family, SOCK_STREAM, 0 ), "Opening socket" );
+
+        ASSERTSOCKOP( bind( fd, ( struct sockaddr *)saddr, rp->ai_addrlen ), "Binding socket" );
+
+        freeaddrinfo( rp );
+
+        ASSERTSOCKOP( listen( fd, 1 ), "Making socket listen" );
+
+        if ( !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
+                        , host, INET6_ADDRSTRLEN ) )
+                return msn_ftp_abort( file, "inet_ntop failed on listening socket" );
+
+        ASSERTSOCKOP( getsockname( fd, ( struct sockaddr *)saddr, &ssize ), "Getting socket name" );
+
+        if( saddr->ss_family == AF_INET )
+                sprintf( port, "%d", ntohs( ( ( struct sockaddr_in *) saddr )->sin_port ) );
+        else
+                sprintf( port, "%d", ntohs( ( ( struct sockaddr_in6 *) saddr )->sin6_port ) );
+
+        return TRUE;
+}
+
+void msn_ftp_invitation_cmd( struct im_connection *ic, char *who, int cookie, char *icmd,
+			     char *trailer )
+{
+	struct msn_message *m = g_new0( struct msn_message, 1 );
+	
+	m->text = g_strdup_printf( "%s"
+		    "Invitation-Command: %s\r\n"
+		    "Invitation-Cookie: %u\r\n"
+		    "%s",
+		    MSN_INVITE_HEADERS,
+		    icmd,
+		    cookie,
+		    trailer);
+	
+	m->who = g_strdup( who );
+
+	msn_sb_write_msg( ic, m );
+}
+
+void msn_ftp_cancel_invite( struct im_connection *ic, char *who,  int cookie, char *code )
+{
+	char buf[64];
+
+	g_snprintf( buf, sizeof( buf ), "Cancel-Code: %s\r\n", code );
+	msn_ftp_invitation_cmd( ic, who, cookie, "CANCEL", buf );
+}
+
+void msn_ftp_transfer_request( struct im_connection *ic, file_transfer_t *file, char *who )
+{
+	unsigned int cookie = time( NULL ); /* TODO: randomize */
+	char buf[2048];
+
+	msn_filetransfer_t *msn_file = g_new0( msn_filetransfer_t, 1 );
+	file->data = msn_file;
+	file->free = msn_ftp_free;
+	file->canceled = msn_ftp_canceled;
+	file->write = msn_ftps_write;
+	msn_file->md = ic->proto_data;
+	msn_file->invite_cookie = cookie;
+	msn_file->handle = g_strdup( who );
+	msn_file->dcc = file;
+	msn_file->md->filetransfers = g_slist_prepend( msn_file->md->filetransfers, msn_file->dcc );
+	msn_file->fd = -1;
+	msn_file->sbufpos = 3;
+
+	g_snprintf( buf, sizeof( buf ), 
+		"Application-Name: File Transfer\r\n"
+		"Application-GUID: {5D3E02AB-6190-11d3-BBBB-00C04F795683}\r\n"
+		"Application-File: %s\r\n"
+		"Application-FileSize: %zd\r\n",
+		file->file_name,
+		file->file_size);
+
+	msn_ftp_invitation_cmd( msn_file->md->ic, msn_file->handle, cookie, "INVITE", buf );
+
+	imcb_file_recv_start( file );
+}
+
+void msn_invitation_invite( struct msn_switchboard *sb, char *handle, unsigned int cookie, char *body, int blen )
+{
+	char *itype = msn_findheader( body, "Application-GUID:", blen );
+	char *name, *size, *invitecookie, *reject = NULL;
+	user_t *u;
+	size_t isize;
+	file_transfer_t *file;
+	
+	if( !itype || strcmp( itype, "{5D3E02AB-6190-11d3-BBBB-00C04F795683}" ) != 0 ) {
+		/* Don't know what that is - don't care */
+		char *iname = msn_findheader( body, "Application-Name:", blen );
+		imcb_log( sb->ic, "Received unknown MSN invitation %s (%s) from %s",
+			  itype ? : "with no GUID", iname ? iname : "no application name", handle );
+		g_free( iname );
+		reject = "REJECT_NOT_INSTALLED";
+	} else if ( 
+		!( name = msn_findheader( body, "Application-File:", blen )) || 
+		!( size = msn_findheader( body, "Application-FileSize:", blen )) || 
+		!( invitecookie = msn_findheader( body, "Invitation-Cookie:", blen)) ||
+		!( isize = atoll( size ) ) ) { 
+		imcb_log( sb->ic, "Received corrupted transfer request from %s"
+			  "(name=%s, size=%s, invitecookie=%s)",
+			  handle, name, size, invitecookie );
+		reject = "REJECT";
+	} else if ( !( u = user_findhandle( sb->ic, handle ) ) ) {
+		imcb_log( sb->ic, "Error in parsing transfer request, User '%s'"
+			  "is not in contact list", handle );
+		reject = "REJECT";
+	} else if ( !( file = imcb_file_send_start( sb->ic, handle, name, isize ) ) ) {
+		imcb_log( sb->ic, "Error initiating transfer for request from %s for %s",
+			  handle, name );
+		reject = "REJECT";
+	} else {
+		msn_filetransfer_t *msn_file = g_new0( msn_filetransfer_t, 1 );
+		file->data = msn_file;
+		file->accept = msn_ftpr_accept;
+		file->free = msn_ftp_free;
+		file->finished = msn_ftp_finished;
+		file->canceled = msn_ftp_canceled;
+		file->write_request = msn_ftpr_write_request;
+		msn_file->md = sb->ic->proto_data;
+		msn_file->invite_cookie = cookie;
+		msn_file->handle = g_strdup( handle );
+		msn_file->dcc = file;
+		msn_file->md->filetransfers = g_slist_prepend( msn_file->md->filetransfers, msn_file->dcc );
+		msn_file->fd = -1;
+	}
+
+	if( reject )
+		msn_ftp_cancel_invite( sb->ic, sb->who, cookie, reject );
+
+	g_free( name );
+	g_free( size );
+	g_free( invitecookie );
+	g_free( itype );
+}
+
+msn_filetransfer_t* msn_find_filetransfer( struct msn_data *md, unsigned int cookie, char *handle )
+{
+	GSList *l;
+	
+	for( l = md->filetransfers; l; l = l->next ) {
+		msn_filetransfer_t *file = ( (file_transfer_t*) l->data )->data;
+		if( file->invite_cookie == cookie && strcmp( handle, file->handle ) == 0 ) {
+			return file;
+		}
+	}
+	return NULL;
+}
+
+gboolean msn_ftps_connected( gpointer data, gint fd, b_input_condition cond )
+{
+	file_transfer_t *file = data;
+	msn_filetransfer_t *msn_file = file->data;
+	struct sockaddr_storage clt_addr;
+	socklen_t ssize = sizeof( clt_addr );
+	
+	debug( "Connected to MSNFTP client" );
+	
+	ASSERTSOCKOP( msn_file->fd = accept( fd, (struct sockaddr *) &clt_addr, &ssize ), "Accepting connection" );
+
+	closesocket( fd );
+	fd = msn_file->fd;
+	sock_make_nonblocking( fd );
+
+	msn_file->r_event_id = b_input_add( fd, GAIM_INPUT_READ, msn_ftp_read, file );
+
+	return FALSE;
+}
+
+void msn_invitations_accept( msn_filetransfer_t *msn_file, struct msn_switchboard *sb, char *handle, unsigned int cookie, char *body, int blen )
+{
+	file_transfer_t *file = msn_file->dcc;
+	char buf[1024];
+	unsigned int acookie = time ( NULL );
+	char host[INET6_ADDRSTRLEN];
+	char port[6];
+
+	msn_file->auth_cookie = acookie;
+
+	if( !msn_ftp_listen( msn_file, host, port ) )
+	    return;
+
+	msn_file->r_event_id = b_input_add( msn_file->fd, GAIM_INPUT_READ, msn_ftps_connected, file );
+
+	g_snprintf( buf, sizeof( buf ),
+		    "IP-Address: %s\r\n"
+		    "Port: %s\r\n"
+		    "AuthCookie: %d\r\n"
+		    "Launch-Application: FALSE\r\n"
+		    "Request-Data: IP-Address:\r\n\r\n",
+		    host,
+		    port,
+		    msn_file->auth_cookie );
+
+	msn_ftp_invitation_cmd( msn_file->md->ic, handle, msn_file->invite_cookie, "ACCEPT", buf );
+}
+
+void msn_invitationr_accept( msn_filetransfer_t *msn_file, struct msn_switchboard *sb, char *handle, unsigned int cookie, char *body, int blen ) {
+	file_transfer_t *file = msn_file->dcc;
+	char *authcookie, *ip, *port;
+
+	if( !( authcookie = msn_findheader( body, "AuthCookie:", blen ) ) ||
+	    !( ip = msn_findheader( body, "IP-Address:", blen ) ) ||
+	    !( port = msn_findheader( body, "Port:", blen ) ) ) {
+		msn_ftp_abort( file, "Received invalid accept reply" );
+	} else if( 
+		( msn_file->fd = proxy_connect( ip, atoi( port ), msn_ftp_connected, file ) )
+		< 0 ) {
+			msn_ftp_abort( file, "Error connecting to MSN client" );
+	} else
+		msn_file->auth_cookie = strtoul( authcookie, NULL, 10 );
+
+	g_free( authcookie );
+	g_free( ip );
+	g_free( port );
+}
+
+void msn_invitation_accept( struct msn_switchboard *sb, char *handle, unsigned int cookie, char *body, int blen )
+{
+	msn_filetransfer_t *msn_file = msn_find_filetransfer( sb->ic->proto_data, cookie, handle );
+	file_transfer_t *file = msn_file ? msn_file->dcc : NULL;
+	
+	if( !msn_file  )
+		imcb_log( sb->ic, "Received invitation ACCEPT message for unknown invitation (already aborted?)" );
+	else if( file->sending ) 
+		msn_invitations_accept( msn_file, sb, handle, cookie, body, blen );
+	else
+		msn_invitationr_accept( msn_file, sb, handle, cookie, body, blen );
+}
+
+void msn_invitation_cancel( struct msn_switchboard *sb, char *handle, unsigned int cookie, char *body, int blen )
+{
+	msn_filetransfer_t *msn_file = msn_find_filetransfer( sb->ic->proto_data, cookie, handle );
+	
+	if( !msn_file )
+		imcb_log( sb->ic, "Received invitation CANCEL message for unknown invitation (already aborted?)" );
+	else
+		msn_ftp_abort( msn_file->dcc, msn_findheader( body, "Cancel-Code:", blen ) );
+}
+
+int msn_ftp_write( file_transfer_t *file, char *format, ... )
+{
+	msn_filetransfer_t *msn_file = file->data;
+	va_list params;
+	int st;
+	char *s;
+	
+	va_start( params, format );
+	s = g_strdup_vprintf( format, params );
+	va_end( params );
+	
+	st = write( msn_file->fd, s, strlen( s ) );
+	if( st != strlen( s ) )
+		return msn_ftp_abort( file, "Error sending data over MSNFTP connection: %s",
+				strerror( errno ) );
+	
+	g_free( s );
+	return 1;
+}
+
+gboolean msn_ftp_connected( gpointer data, gint fd, b_input_condition cond )
+{
+	file_transfer_t *file = data;
+	msn_filetransfer_t *msn_file = file->data;
+	
+	debug( "Connected to MSNFTP server, starting authentication" );
+	if( !msn_ftp_write( file, "VER MSNFTP\r\n" ) ) 
+		return FALSE;
+	
+	sock_make_nonblocking( msn_file->fd );
+	msn_file->r_event_id = b_input_add( msn_file->fd, GAIM_INPUT_READ, msn_ftp_read, file );
+	
+	return FALSE;
+}
+
+gboolean msn_ftp_handle_command( file_transfer_t *file, char* line )
+{
+	msn_filetransfer_t *msn_file = file->data;
+	char **cmd = msn_linesplit( line );
+	int count = 0;
+	if( cmd[0] ) while( cmd[++count] );
+	
+	if( count < 1 )
+		return msn_ftp_abort( file, "Missing command in MSNFTP communication" );
+	
+	if( strcmp( cmd[0], "VER" ) == 0 ) {
+		if( strcmp( cmd[1], "MSNFTP" ) != 0 )
+			return msn_ftp_abort( file, "Unsupported filetransfer protocol: %s", cmd[1] );
+		if( file->sending )
+			msn_ftp_write( file, "VER MSNFTP\r\n" );
+		else 
+			msn_ftp_write( file, "USR %s %u\r\n", msn_file->md->ic->acc->user, msn_file->auth_cookie );
+	} else if( strcmp( cmd[0], "FIL" ) == 0 ) {
+		if( strtoul( cmd[1], NULL, 10 ) != file->file_size )
+			return msn_ftp_abort( file, "FIL reply contains a different file size than the size in the invitation" );
+		msn_ftp_write( file, "TFR\r\n" );
+		msn_file->status |= MSN_TRANSFER_RECEIVING;
+	} else if( strcmp( cmd[0], "USR" ) == 0 ) {
+		if( ( strcmp( cmd[1], msn_file->handle ) != 0 ) ||
+		    ( strtoul( cmd[2], NULL, 10 ) != msn_file->auth_cookie ) )
+			msn_ftp_abort( file, "Authentication failed. "
+				"Expected handle: %s (got %s), cookie: %u (got %s)",
+				msn_file->handle, cmd[1],
+				msn_file->auth_cookie, cmd[2] );
+		msn_ftp_write( file, "FIL %zu\r\n", file->file_size);
+	} else if( strcmp( cmd[0], "TFR" ) == 0 ) {
+		file->write_request( file );
+	} else if( strcmp( cmd[0], "BYE" ) == 0 ) {
+		unsigned int retcode = count > 1 ? atoi(cmd[1]) : 1;
+
+		if( ( retcode==16777989 ) || ( retcode==16777987 ) )
+			imcb_file_finished( file );
+		else if( retcode==2147942405 )
+			imcb_file_canceled( file, "Failure: receiver is out of disk space" );
+		else if( retcode==2164261682 )
+			imcb_file_canceled( file, "Failure: receiver cancelled the transfer" );
+		else if( retcode==2164261683 )
+			imcb_file_canceled( file, "Failure: sender has cancelled the transfer" );
+		else if( retcode==2164261694 )
+			imcb_file_canceled( file, "Failure: connection is blocked" );
+		else {
+			char buf[128];
+
+			sprintf( buf, "Failure: unknown BYE code: %d", retcode);
+			imcb_file_canceled( file, buf );
+		}
+	} else if( strcmp( cmd[0], "CCL" ) == 0 ) {
+		imcb_file_canceled( file, "Failure: receiver cancelled the transfer" );
+	} else {
+		msn_ftp_abort( file, "Received invalid command %s from msn client", cmd[0] );
+	}
+	return TRUE;
+}
+
+gboolean msn_ftp_send( gpointer data, gint fd, b_input_condition cond )
+{
+	file_transfer_t *file = data;
+	msn_filetransfer_t *msn_file = file->data;
+
+	msn_file->w_event_id = 0;
+
+	file->write_request( file );
+
+	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).
+ * This got a bit complicated because (at least) amsn expects packets of size 2045.
+ */
+gboolean msn_ftps_write( file_transfer_t *file, char *buffer, unsigned int len )
+{
+	msn_filetransfer_t *msn_file = file->data;
+        int ret, overflow;
+
+	/* what we can't send now */
+	overflow = msn_file->sbufpos + len - MSNFTP_PSIZE;
+
+	/* append what we can do the send buffer */
+	memcpy( msn_file->sbuf + msn_file->sbufpos, buffer, MIN( len, MSNFTP_PSIZE - msn_file->sbufpos ) );
+	msn_file->sbufpos += MIN( len, MSNFTP_PSIZE - msn_file->sbufpos );
+
+	/* if we don't have enough for a full packet and there's more wait for it */
+	if( ( msn_file->sbufpos < MSNFTP_PSIZE ) && 
+	    ( msn_file->data_sent + msn_file->sbufpos - 3 < file->file_size ) ) {
+		if( !msn_file->w_event_id )
+			msn_file->w_event_id = b_input_add( msn_file->fd, GAIM_INPUT_WRITE, msn_ftp_send, file );
+		return TRUE;
+	}
+
+	/* Accumulated enough data, lets send something out */
+
+	msn_file->sbuf[0] = 0;
+	msn_file->sbuf[1] = ( msn_file->sbufpos - 3 ) & 0xff;
+	msn_file->sbuf[2] = ( ( msn_file->sbufpos - 3 ) >> 8 ) & 0xff;
+
+        ASSERTSOCKOP( ret = send( msn_file->fd, msn_file->sbuf, msn_file->sbufpos, 0 ), "Sending" );
+
+        msn_file->data_sent += ret - 3;
+
+        /* TODO: this should really not be fatal */
+        if( ret < msn_file->sbufpos )
+                return msn_ftp_abort( file, "send() sent %d instead of %d (send buffer full!)", ret, msn_file->sbufpos );
+
+	msn_file->sbufpos = 3;
+
+	if( overflow > 0 ) {
+		while( overflow > ( MSNFTP_PSIZE - 3 ) ) {
+			if( !msn_ftps_write( file, buffer + len - overflow, MSNFTP_PSIZE - 3 ) )
+				return FALSE;
+			overflow -= MSNFTP_PSIZE - 3;
+		}
+		return msn_ftps_write( file, buffer + len - overflow, overflow );
+	}
+
+	if( msn_file->data_sent == file->file_size ) {
+		if( msn_file->w_event_id ) {
+			b_event_remove( msn_file->w_event_id );
+			msn_file->w_event_id = 0;
+		}
+	} else {
+		/* we might already be listening if this is data from an overflow */
+		if( !msn_file->w_event_id )
+			msn_file->w_event_id = b_input_add( msn_file->fd, GAIM_INPUT_WRITE, msn_ftp_send, file );
+	}
+
+        return TRUE;
+}
+
+/* Binary part of the file transfer protocol */
+gboolean msn_ftpr_read( file_transfer_t *file ) 
+{
+	msn_filetransfer_t *msn_file = file->data;
+	int st;
+	unsigned char buf[3];
+
+	if( msn_file->data_remaining ) {
+		msn_file->r_event_id = 0;
+
+		ASSERTSOCKOP( st = read( msn_file->fd, file->buffer, MIN( sizeof( file->buffer ), msn_file->data_remaining ) ), "Receiving" );
+
+		if( st == 0 )
+			return msn_ftp_abort( file, "Remote end closed connection");
+
+		msn_file->data_sent += st;
+
+		msn_file->data_remaining -= st;
+
+		file->write( file, file->buffer, st );
+
+		if( msn_file->data_sent >= file->file_size )
+			imcb_file_finished( file );
+
+		return FALSE;
+	} else {
+		ASSERTSOCKOP( st = read( msn_file->fd, buf, 1 ), "Receiving" );
+		if( st == 0 ) {
+			return msn_ftp_abort( file, "read returned EOF while reading data header from msn client" );
+		} else if( buf[0] == '\r' || buf[0] == '\n' ) {
+			debug( "Discarding extraneous newline" );
+		} else if( buf[0] != 0 ) {
+			msn_ftp_abort( file, "Remote end canceled the transfer");
+			/* don't really care about these last 2 (should be 0,0) */
+			read( msn_file->fd, buf, 2 );
+			return FALSE;
+		} else {
+			unsigned int size;
+			ASSERTSOCKOP( st = read( msn_file->fd, buf, 2 ), "Receiving" );
+			if( st < 2 )
+				return msn_ftp_abort( file, "read returned EOF while reading data header from msn client" );
+
+			size = buf[0] + ((unsigned int) buf[1] << 8);
+			msn_file->data_remaining = size;
+		}
+	}
+	return TRUE;
+}
+
+/* Text mode part of the file transfer protocol */
+gboolean msn_ftp_txtproto( file_transfer_t *file )
+{
+	msn_filetransfer_t *msn_file = file->data;
+	int i = msn_file->tbufpos, st;
+	char *tbuf = msn_file->tbuf;
+
+	ASSERTSOCKOP( st = read( msn_file->fd, 
+				 tbuf + msn_file->tbufpos, 
+				 sizeof( msn_file->tbuf ) - msn_file->tbufpos ),
+				 "Receiving" );
+
+	if( st == 0 )
+		return msn_ftp_abort( file, "read returned EOF while reading text from msn client" );
+
+	msn_file->tbufpos += st;
+
+	do {
+		for( ;i < msn_file->tbufpos; i++ ) {
+			if( tbuf[i] == '\n' || tbuf[i] == '\r' ) {
+				tbuf[i] = '\0';
+				if( i > 0 )
+					msn_ftp_handle_command( file, tbuf );
+				else
+					while( tbuf[i] == '\n' || tbuf[i] == '\r' ) i++;
+				memmove( tbuf, tbuf + i + 1, msn_file->tbufpos - i - 1 );
+				msn_file->tbufpos -= i + 1;
+				i = 0;
+				break;
+			}
+		}
+	} while ( i < msn_file->tbufpos );
+
+	if( msn_file->tbufpos == sizeof( msn_file->tbuf ) )
+		return msn_ftp_abort( file, 
+				      "Line exceeded %d bytes in text protocol", 
+				      sizeof( msn_file->tbuf ) );
+	return TRUE;
+}
+
+gboolean msn_ftp_read( gpointer data, gint fd, b_input_condition cond )
+{
+	file_transfer_t *file = data;
+	msn_filetransfer_t *msn_file = file->data;
+	
+	if( msn_file->status & MSN_TRANSFER_RECEIVING )
+		return msn_ftpr_read( file );
+	else
+		return msn_ftp_txtproto( file );
+}
+
+void msn_ftp_free( file_transfer_t *file )
+{
+	msn_filetransfer_t *msn_file = file->data;
+	
+	if( msn_file->r_event_id )
+		b_event_remove( msn_file->r_event_id );
+
+	if( msn_file->w_event_id )
+		b_event_remove( msn_file->w_event_id );
+
+	if( msn_file->fd != -1 )
+		closesocket( msn_file->fd );
+
+	msn_file->md->filetransfers = g_slist_remove( msn_file->md->filetransfers, msn_file->dcc );
+	
+	g_free( msn_file->handle );
+	
+	g_free( msn_file );
+}
+
+void msn_ftpr_accept( file_transfer_t *file )
+{
+	msn_filetransfer_t *msn_file = file->data;
+
+	msn_ftp_invitation_cmd( msn_file->md->ic, msn_file->handle, msn_file->invite_cookie, "ACCEPT", 
+				"Launch-Application: FALSE\r\n" 
+				"Request-Data: IP-Address:\r\n");
+}
+
+void msn_ftp_finished( file_transfer_t *file )
+{
+	msn_ftp_write( file, "BYE 16777989\r\n" );
+}
+
+void msn_ftp_canceled( file_transfer_t *file, char *reason )
+{
+	msn_filetransfer_t *msn_file = file->data;
+
+	msn_ftp_cancel_invite( msn_file->md->ic, msn_file->handle, 
+			       msn_file->invite_cookie, 
+			       file->status & FT_STATUS_TRANSFERRING ? 
+					"FTTIMEOUT" : 
+					"FAIL" );
+
+	imcb_log( msn_file->md->ic, "File transfer aborted: %s", reason );
+}
+
+gboolean msn_ftpr_write_request( file_transfer_t *file )
+{
+	msn_filetransfer_t *msn_file = file->data;
+	if( msn_file->r_event_id != 0 ) {
+		msn_ftp_abort( file, 
+					"BUG in MSN file transfer:"
+					"write_request called when"
+					"already watching for input" );
+		return FALSE;
+	}
+
+	msn_file->r_event_id = 
+		b_input_add( msn_file->fd, GAIM_INPUT_READ, msn_ftp_read, file );
+
+	return TRUE;
+}
diff --git a/protocols/msn/invitation.h b/protocols/msn/invitation.h
new file mode 100644
index 00000000..289efd7b
--- /dev/null
+++ b/protocols/msn/invitation.h
@@ -0,0 +1,82 @@
+/********************************************************************\
+* BitlBee -- An IRC to other IM-networks gateway                     *
+*                                                                    *
+* Copyright 2006 Marijn Kruisselbrink and others                     *
+\********************************************************************/
+
+/* MSN module - File transfer support             */
+
+/*
+ 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
+ */
+
+#ifndef _MSN_INVITATION_H
+#define _MSN_INVITATION_H
+
+#include "msn.h"
+
+#define MSN_INVITE_HEADERS	"MIME-Version: 1.0\r\n" \
+				"Content-Type: text/x-msmsgsinvite; charset=UTF-8\r\n" \
+				"\r\n"
+
+#define MSNFTP_PSIZE 2048
+
+typedef enum {
+	MSN_TRANSFER_RECEIVING	= 1,
+	MSN_TRANSFER_SENDING	= 2
+} msn_filetransfer_status_t;
+
+typedef struct msn_filetransfer
+{
+/* Generic invitation data */	
+	/* msn_data instance this invitation was received with. */
+	struct msn_data *md;
+	/* Cookie specifying this invitation. */
+	unsigned int invite_cookie;
+	/* Handle of user that started this invitation. */
+	char *handle;
+
+/* File transfer specific data */
+	/* Current status of the file transfer. */
+	msn_filetransfer_status_t status;
+	/* Pointer to the dcc structure for this transfer. */
+	file_transfer_t *dcc;
+	/* Socket the transfer is taking place over. */
+	int fd;
+	/* Cookie received in the original invitation, this must be sent as soon as
+	   a connection has been established. */
+	unsigned int auth_cookie;
+	/* Data remaining to be received in the current packet. */
+	unsigned int data_remaining;
+	/* Buffer containing received, but unprocessed text. */
+	char tbuf[256];
+	unsigned int tbufpos;
+	
+	unsigned int data_sent;
+
+	gint r_event_id;
+	gint w_event_id;
+	
+	unsigned char sbuf[2048];
+	int sbufpos;
+
+} msn_filetransfer_t;
+
+void msn_invitation_invite( struct msn_switchboard *sb, char *handle, unsigned int cookie, char *body, int blen );
+void msn_invitation_accept( struct msn_switchboard *sb, char *handle, unsigned int cookie, char *body, int blen );
+void msn_invitation_cancel( struct msn_switchboard *sb, char *handle, unsigned int cookie, char *body, int blen );
+
+#endif
diff --git a/protocols/msn/msn.c b/protocols/msn/msn.c
index 046b2772..590a1382 100644
--- a/protocols/msn/msn.c
+++ b/protocols/msn/msn.c
@@ -76,6 +76,10 @@ static void msn_logout( struct im_connection *ic )
 	
 	if( md )
 	{
+		while( md->filetransfers ) {
+			imcb_file_canceled( md->filetransfers->data, "Closing msn connection" );
+		}
+		
 		if( md->fd >= 0 )
 			closesocket( md->fd );
 		
@@ -337,6 +341,7 @@ void msn_initmodule()
 	ret->rem_deny = msn_rem_deny;
 	ret->send_typing = msn_send_typing;
 	ret->handle_cmp = g_strcasecmp;
+	ret->transfer_request = msn_ftp_transfer_request;
 
 	register_protocol(ret);
 }
diff --git a/protocols/msn/msn.h b/protocols/msn/msn.h
index 7c849acf..e2badbf9 100644
--- a/protocols/msn/msn.h
+++ b/protocols/msn/msn.h
@@ -68,6 +68,7 @@ struct msn_data
 	GSList *switchboards;
 	int sb_failures;
 	time_t first_sb_failure;
+	GSList *filetransfers;
 	
 	const struct msn_away_state *away_state;
 	int buddycount;
@@ -180,4 +181,7 @@ void msn_sb_destroy( struct msn_switchboard *sb );
 gboolean msn_sb_connected( gpointer data, gint source, b_input_condition cond );
 int msn_sb_write_msg( struct im_connection *ic, struct msn_message *m );
 
+/* invitation.c */
+void msn_ftp_transfer_request( struct im_connection *ic, file_transfer_t *ft, char *who );
+
 #endif //_MSN_H
diff --git a/protocols/msn/sb.c b/protocols/msn/sb.c
index e9526234..b60a9a8b 100644
--- a/protocols/msn/sb.c
+++ b/protocols/msn/sb.c
@@ -28,6 +28,7 @@
 #include "msn.h"
 #include "passport.h"
 #include "md5.h"
+#include "invitation.h"
 
 static gboolean msn_sb_callback( gpointer data, gint source, b_input_condition cond );
 static int msn_sb_command( gpointer data, char **cmd, int num_parts );
@@ -167,7 +168,16 @@ int msn_sb_sendmessage( struct msn_switchboard *sb, char *text )
 		int i, j;
 		
 		/* Build the message. Convert LF to CR-LF for normal messages. */
-		if( strcmp( text, TYPING_NOTIFICATION_MESSAGE ) != 0 )
+		if( strcmp( text, TYPING_NOTIFICATION_MESSAGE ) == 0 )
+		{
+			i = strlen( MSN_TYPING_HEADERS ) + strlen( sb->ic->acc->user );
+			buf = g_new0( char, i );
+			i = g_snprintf( buf, i, MSN_TYPING_HEADERS, sb->ic->acc->user );
+		} else if( strncmp( text, MSN_INVITE_HEADERS, sizeof( MSN_INVITE_HEADERS ) - 1 ) == 0 ) 
+		{
+			buf = g_strdup( text );
+			i = strlen( buf );
+		} else
 		{
 			buf = g_new0( char, sizeof( MSN_MESSAGE_HEADERS ) + strlen( text ) * 2 + 1 );
 			i = strlen( MSN_MESSAGE_HEADERS );
@@ -181,12 +191,6 @@ int msn_sb_sendmessage( struct msn_switchboard *sb, char *text )
 				buf[i++] = text[j];
 			}
 		}
-		else
-		{
-			i = strlen( MSN_TYPING_HEADERS ) + strlen( sb->ic->acc->user );
-			buf = g_new0( char, i );
-			i = g_snprintf( buf, i, MSN_TYPING_HEADERS, sb->ic->acc->user );
-		}
 		
 		/* Build the final packet (MSG command + the message). */
 		packet = g_strdup_printf( "MSG %d N %d\r\n%s", ++sb->trId, i, buf );
@@ -686,62 +690,41 @@ static int msn_sb_message( gpointer data, char *msg, int msglen, char **cmd, int
 		}
 		else if( g_strncasecmp( ct, "text/x-msmsgsinvite", 19 ) == 0 )
 		{
-			char *itype = msn_findheader( body, "Application-GUID:", blen );
-			char buf[1024];
+			char *command = msn_findheader( body, "Invitation-Command:", blen );
+			char *cookie = msn_findheader( body, "Invitation-Cookie:", blen );
+			unsigned int icookie;
 			
 			g_free( ct );
 			
-			*buf = 0;
-			
-			if( !itype )
-				return( 1 );
-			
-			/* File transfer. */
-			if( strcmp( itype, "{5D3E02AB-6190-11d3-BBBB-00C04F795683}" ) == 0 )
-			{
-				char *name = msn_findheader( body, "Application-File:", blen );
-				char *size = msn_findheader( body, "Application-FileSize:", blen );
-				
-				if( name && size )
-				{
-					g_snprintf( buf, sizeof( buf ), "<< \x02""BitlBee\x02"" - Filetransfer: `%s', %s bytes >>\n"
-					            "Filetransfers are not supported by BitlBee for now...", name, size );
-				}
-				else
-				{
-					strcpy( buf, "<< \x02""BitlBee\x02"" - Corrupted MSN filetransfer invitation message >>" );
-				}
-				
-				if( name ) g_free( name );
-				if( size ) g_free( size );
-			}
-			else
-			{
-				char *iname = msn_findheader( body, "Application-Name:", blen );
-				
-				g_snprintf( buf, sizeof( buf ), "<< \x02""BitlBee\x02"" - Unknown MSN invitation - %s (%s) >>",
-				                                itype, iname ? iname : "no name" );
-				
-				if( iname ) g_free( iname );
+			/* Every invite should have both a Command and Cookie header */
+			if( !command || !cookie ) {
+				g_free( command );
+				g_free( cookie );
+				imcb_log( ic, "Warning: No command or cookie from %s", sb->who );
+				return 1;
 			}
 			
-			g_free( itype );
+			icookie = strtoul( cookie, NULL, 10 );
+			g_free( cookie );
 			
-			if( !*buf )
-				return( 1 );
-			
-			if( sb->who )
-			{
-				imcb_buddy_msg( ic, cmd[1], buf, 0, 0 );
-			}
-			else if( sb->chat )
-			{
-				imcb_chat_msg( sb->chat, cmd[1], buf, 0, 0 );
-			}
-			else
-			{
-				/* PANIC! */
+			if( g_strncasecmp( command, "INVITE", 6 ) == 0 ) {
+				msn_invitation_invite( sb, cmd[1], icookie, body, blen );
+			} else if( g_strncasecmp( command, "ACCEPT", 6 ) == 0 ) {
+				msn_invitation_accept( sb, cmd[1], icookie, body, blen );
+			} else if( g_strncasecmp( command, "CANCEL", 6 ) == 0 ) {
+				msn_invitation_cancel( sb, cmd[1], icookie, body, blen );
+			} else {
+				imcb_log( ic, "Warning: Received invalid invitation with "
+						"command %s from %s", command, sb->who );
 			}
+			
+			g_free( command );
+		}
+		else if( g_strncasecmp( ct, "application/x-msnmsgrp2p", 24 ) == 0 ) 
+		{
+			imcb_error( sb->ic, "Cannot receive file from %s: BitlBee does not "
+					"support msnmsgrp2p yet.", sb->who );
+			g_free( ct );
 		}
 		else if( g_strncasecmp( ct, "text/x-msmsgscontrol", 20 ) == 0 )
 		{