hexchat/src/common/dcc.c

/* X-Chat
 * Copyright (C) 1998-2006 Peter Zelezny.
 * Copyright (C) 2006 Damjan Jovanovic
 *
 * 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 St, Fifth Floor, Boston, MA 02110-1301, USA
 *
 * Wayne Conrad, 3 Apr 1999: Color-coded DCC file transfer status windows
 * Bernhard Valenti <bernhard.valenti@gmx.net> 2000-11-21: Fixed DCC send behind nat
 *
 * 2001-03-08 Added support for getting "dcc_ip" config parameter.
 * Jim Seymour (jseymour@LinxNet.com)
 */

/* Required to make lseek use off64_t, but doesn't work on Windows */
#define _FILE_OFFSET_BITS 64

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <errno.h>
#include <sys/stat.h>
#include <fcntl.h>

#define WANTSOCKET
#define WANTARPA
#define WANTDNS
#include "inet.h"

#ifdef WIN32
#include <windows.h>
#include <io.h>
#else
#include <unistd.h>
#endif

#include "hexchat.h"
#include "util.h"
#include "fe.h"
#include "outbound.h"
#include "inbound.h"
#include "network.h"
#include "plugin.h"
#include "server.h"
#include "text.h"
#include "url.h"
#include "hexchatc.h"

/* Setting _FILE_OFFSET_BITS to 64 doesn't change lseek to use off64_t on Windows, so override lseek to the version that does */
#ifdef WIN32
#define lseek _lseeki64
#endif

static char *dcctypes[] = { "SEND", "RECV", "CHAT", "CHAT" };

struct dccstat_info dccstat[] = {
	{N_("Waiting"), 1 /*black */ },
	{N_("Active"), 12 /*cyan */ },
	{N_("Failed"), 4 /*red */ },
	{N_("Done"), 3 /*green */ },
	{N_("Connect"), 1 /*black */ },
	{N_("Aborted"), 4 /*red */ },
};

static int dcc_global_throttle;	/* 0x1 = sends, 0x2 = gets */
static gint64 dcc_sendcpssum, dcc_getcpssum;

static struct DCC *new_dcc (void);
static void dcc_close (struct DCC *dcc, int dccstat, int destroy);
static gboolean dcc_send_data (GIOChannel *, GIOCondition, struct DCC *);
static gboolean dcc_read (GIOChannel *, GIOCondition, struct DCC *);
static gboolean dcc_read_ack (GIOChannel *source, GIOCondition condition, struct DCC *dcc);

static int new_id()
{
	static int id = 0;
	if (id == 0)
	{
		/* start the first ID at a random number for pseudo security */
		/* 1 - 255 */
		id = RAND_INT(255) + 1;
		/* ignore overflows, since it can go to 2 billion */
	}
	return id++;
}

static double
timeval_diff (GTimeVal *greater,
				 GTimeVal *less)
{
	long usecdiff;
	double result;
	
	result = greater->tv_sec - less->tv_sec;
	usecdiff = (long) greater->tv_usec - less->tv_usec;
	result += (double) usecdiff / 1000000;
	
	return result;
}

static void
dcc_unthrottle (struct DCC *dcc)
{
	/* don't unthrottle here, but delegate to funcs */
	if (dcc->type == TYPE_RECV)
		dcc_read (NULL, 0, dcc);
	else
		dcc_send_data (NULL, 0, dcc);
}

static void
dcc_calc_cps (struct DCC *dcc)
{
	GTimeVal now;
	gint64 oldcps;
	double timediff, startdiff;
	int glob_throttle_bit, wasthrottled;
	gint64 *cpssum;
	int glob_limit;
	goffset pos, posdiff;

	g_get_current_time (&now);

	/* the pos we use for sends is an average
		between pos and ack */
	if (dcc->type == TYPE_SEND)
	{
		/* carefull to avoid 32bit overflow */
		pos = dcc->pos - ((dcc->pos - dcc->ack) / 2);
		glob_throttle_bit = 0x1;
		cpssum = &dcc_sendcpssum;
		glob_limit = prefs.hex_dcc_global_max_send_cps;
	}
	else
	{
		pos = dcc->pos;
		glob_throttle_bit = 0x2;
		cpssum = &dcc_getcpssum;
		glob_limit = prefs.hex_dcc_global_max_get_cps;
	}

	if (!dcc->firstcpstv.tv_sec && !dcc->firstcpstv.tv_usec)
		dcc->firstcpstv = now;
	else
	{
		startdiff = timeval_diff (&now, &dcc->firstcpstv);
		if (startdiff < 1)
			startdiff = 1;
		else if (startdiff > CPS_AVG_WINDOW)
			startdiff = CPS_AVG_WINDOW;

		timediff = timeval_diff (&now, &dcc->lastcpstv);
		if (timediff > startdiff)
			timediff = startdiff = 1;

		posdiff = pos - dcc->lastcpspos;
		oldcps = dcc->cps;
		dcc->cps = (gint64) ((posdiff / timediff) * (timediff / startdiff) + dcc->cps * (1.0 - (timediff / startdiff)));

		*cpssum += dcc->cps - oldcps;
	}

	dcc->lastcpspos = pos;
	dcc->lastcpstv = now;

	/* now check cps against set limits... */
	wasthrottled = dcc->throttled;

	/* check global limits first */
	dcc->throttled &= ~0x2;
	if (glob_limit > 0 && *cpssum >= glob_limit)
	{
		dcc_global_throttle |= glob_throttle_bit;
		if (dcc->maxcps >= 0)
			dcc->throttled |= 0x2;
	}
	else
		dcc_global_throttle &= ~glob_throttle_bit;

	/* now check per-connection limit */
	if (dcc->maxcps > 0 && dcc->cps > dcc->maxcps)
		dcc->throttled |= 0x1;
	else
		dcc->throttled &= ~0x1;

	/* take action */
	if (wasthrottled && !dcc->throttled)
		dcc_unthrottle (dcc);
}

static void
dcc_remove_from_sum (struct DCC *dcc)
{
	if (dcc->dccstat != STAT_ACTIVE)
		return;
	if (dcc->type == TYPE_SEND)
		dcc_sendcpssum -= dcc->cps;
	else if (dcc->type == TYPE_RECV)
		dcc_getcpssum -= dcc->cps;
}

gboolean
is_dcc (struct DCC *dcc)
{
	GSList *list = dcc_list;
	while (list)
	{
		if (list->data == dcc)
			return TRUE;
		list = list->next;
	}
	return FALSE;
}

gboolean
is_dcc_completed (struct DCC *dcc)
{
	if (dcc != NULL)
		return (dcc->dccstat == STAT_FAILED || dcc->dccstat == STAT_DONE || dcc->dccstat == STAT_ABORTED);

	return FALSE;
}

/* this is called from hexchat.c:hexchat_misc_checks() every 1 second. */

void
dcc_check_timeouts (void)
{
	struct DCC *dcc;
	time_t tim = time (0);
	GSList *next, *list = dcc_list;

	while (list)
	{
		dcc = (struct DCC *) list->data;
		next = list->next;

		switch (dcc->dccstat)
		{
		case STAT_ACTIVE:
			dcc_calc_cps (dcc);
			fe_dcc_update (dcc);

			if (dcc->type == TYPE_SEND || dcc->type == TYPE_RECV)
			{
				if (prefs.hex_dcc_stall_timeout > 0)
				{
					if (!dcc->throttled
						&& tim - dcc->lasttime > prefs.hex_dcc_stall_timeout)
					{
						EMIT_SIGNAL (XP_TE_DCCSTALL, dcc->serv->front_session,
										 dcctypes[dcc->type],
										 file_part (dcc->file), dcc->nick, NULL, 0);
						dcc_close (dcc, STAT_ABORTED, FALSE);
					}
				}
			}
			break;
		case STAT_QUEUED:
			if (dcc->type == TYPE_SEND || dcc->type == TYPE_CHATSEND)
			{
				if (tim - dcc->offertime > prefs.hex_dcc_timeout)
				{
					if (prefs.hex_dcc_timeout > 0)
					{
						EMIT_SIGNAL (XP_TE_DCCTOUT, dcc->serv->front_session,
										 dcctypes[dcc->type],
										 file_part (dcc->file), dcc->nick, NULL, 0);
						dcc_close (dcc, STAT_ABORTED, FALSE);
					}
				}
			}
			break;
		case STAT_DONE:
		case STAT_FAILED:
		case STAT_ABORTED:
			if (prefs.hex_dcc_remove)
				dcc_close (dcc, 0, TRUE);
			break;
		}
		list = next;
	}
}

static int
dcc_lookup_proxy (char *host, struct sockaddr_in *addr)
{
	struct hostent *h;
	static char *cache_host = NULL;
	static guint32 cache_addr;

	/* too lazy to thread this, so we cache results */
	if (cache_host)
	{
		if (strcmp (host, cache_host) == 0)
		{
			memcpy (&addr->sin_addr, &cache_addr, 4);
			return TRUE;
		}
		g_free (cache_host);
		cache_host = NULL;
	}

	h = gethostbyname (host);
	if (h != NULL && h->h_length == 4 && h->h_addr_list[0] != NULL)
	{
		memcpy (&addr->sin_addr, h->h_addr, 4);
		memcpy (&cache_addr, h->h_addr, 4);
		cache_host = g_strdup (host);
		/* cppcheck-suppress memleak */
		return TRUE;
	}

	return FALSE;
}

#define DCC_USE_PROXY() (prefs.hex_net_proxy_host[0] && prefs.hex_net_proxy_type>0 && prefs.hex_net_proxy_type<5 && prefs.hex_net_proxy_use!=1)

static int
dcc_connect_sok (struct DCC *dcc)
{
	int sok;
	struct sockaddr_in addr;

	sok = socket (AF_INET, SOCK_STREAM, 0);
	if (sok == -1)
		return -1;

	memset (&addr, 0, sizeof (addr));
	addr.sin_family = AF_INET;
	if (DCC_USE_PROXY ())
	{
		if (!dcc_lookup_proxy (prefs.hex_net_proxy_host, &addr))
		{
			closesocket (sok);
			return -1;
		}
		addr.sin_port = htons (prefs.hex_net_proxy_port);
	}
	else
	{
		addr.sin_port = htons (dcc->port);
		addr.sin_addr.s_addr = htonl (dcc->addr);
	}

	set_nonblocking (sok);
	connect (sok, (struct sockaddr *) &addr, sizeof (addr));

	return sok;
}

static void
dcc_close (struct DCC *dcc, int dccstat, int destroy)
{
	if (dcc->wiotag)
	{
		fe_input_remove (dcc->wiotag);
		dcc->wiotag = 0;
	}

	if (dcc->iotag)
	{
		fe_input_remove (dcc->iotag);
		dcc->iotag = 0;
	}

	if (dcc->sok != -1)
	{
		closesocket (dcc->sok);
		dcc->sok = -1;
	}

	dcc_remove_from_sum (dcc);

	if (dcc->fp != -1)
	{
		close (dcc->fp);
		dcc->fp = -1;

		if(dccstat == STAT_DONE)
		{
			/* if we just completed a dcc receive, move the */
			/* completed file to the completed directory */
			if(dcc->type == TYPE_RECV)
			{			
				/* mgl: change this to handle the case where dccwithnick is set */
				move_file (prefs.hex_dcc_dir, prefs.hex_dcc_completed_dir, 
									 file_part (dcc->destfile), prefs.hex_dcc_permissions);
			}

		}
	}

	dcc->dccstat = dccstat;
	if (dcc->dccchat)
	{
		g_free (dcc->dccchat);
		dcc->dccchat = NULL;
	}

	if (destroy)
	{
		dcc_list = g_slist_remove (dcc_list, dcc);
		fe_dcc_remove (dcc);
		g_free (dcc->proxy);
		g_free (dcc->file);
		g_free (dcc->destfile);
		g_free (dcc->nick);
		g_free (dcc);
		return;
	}

	fe_dcc_update (dcc);
}

void
dcc_abort (session *sess, struct DCC *dcc)
{
	if (dcc)
	{
		switch (dcc->dccstat)
		{
		case STAT_QUEUED:
		case STAT_CONNECTING:
		case STAT_ACTIVE:
			dcc_close (dcc, STAT_ABORTED, FALSE);
			switch (dcc->type)
			{
			case TYPE_CHATSEND:
			case TYPE_CHATRECV:
				EMIT_SIGNAL (XP_TE_DCCCHATABORT, sess, dcc->nick, NULL, NULL,
								 NULL, 0);
				break;
			case TYPE_SEND:
				EMIT_SIGNAL (XP_TE_DCCSENDABORT, sess, dcc->nick,
								 file_part (dcc->file), NULL, NULL, 0);
				break;
			case TYPE_RECV:
				EMIT_SIGNAL (XP_TE_DCCRECVABORT, sess, dcc->nick,
								 dcc->file, NULL, NULL, 0);
			}
			break;
		default:
			dcc_close (dcc, 0, TRUE);
		}
	}
}

void
dcc_notify_kill (struct server *serv)
{
	struct server *replaceserv = 0;
	struct DCC *dcc;
	GSList *list = dcc_list;
	if (serv_list)
		replaceserv = (struct server *) serv_list->data;
	while (list)
	{
		dcc = (struct DCC *) list->data;
		if (dcc->serv == serv)
			dcc->serv = replaceserv;
		list = list->next;
	}
}

struct DCC *
dcc_write_chat (char *nick, char *text)
{
	struct DCC *dcc;
	int len;

	dcc = find_dcc (nick, "", TYPE_CHATRECV);
	if (!dcc)
		dcc = find_dcc (nick, "", TYPE_CHATSEND);
	if (dcc && dcc->dccstat == STAT_ACTIVE)
	{
		len = strlen (text);
		tcp_send_real (NULL, dcc->sok, dcc->serv->write_converter, text, len);
		send (dcc->sok, "\n", 1, 0);
		dcc->size += len;
		fe_dcc_update (dcc);
		return dcc;
	}
	return NULL;
}

/* returns: 0 - ok
				1 - the dcc is closed! */

static int
dcc_chat_line (struct DCC *dcc, char *line)
{
	session *sess;
	char *word[PDIWORDS];
	char *po;
	int ret, i;
	char portbuf[32];
	message_tags_data no_tags = MESSAGE_TAGS_DATA_INIT;

	line = text_convert_invalid (line, -1, dcc->serv->read_converter, unicode_fallback_string, NULL);

	sess = find_dialog (dcc->serv, dcc->nick);
	if (!sess)
		sess = dcc->serv->front_session;

	sprintf (portbuf, "%d", dcc->port);

	word[0] = "DCC Chat Text";
	word[1] = net_ip (dcc->addr);
	word[2] = portbuf;
	word[3] = dcc->nick;
	word[4] = line;
	for (i = 5; i < PDIWORDS; i++)
		word[i] = "\000";

	ret = plugin_emit_print (sess, word, 0);

	/* did the plugin close it? */
	if (!g_slist_find (dcc_list, dcc))
	{
		g_free (line);
		return 1;
	}

	/* did the plugin eat the event? */
	if (ret)
	{
		g_free (line);
		return 0;
	}

	url_check_line (line);

	if (line[0] == 1 && !g_ascii_strncasecmp (line + 1, "ACTION", 6))
	{
		po = strchr (line + 8, '\001');
		if (po)
			po[0] = 0;
		inbound_action (sess, dcc->serv->nick, dcc->nick, "", line + 8, FALSE,
							 FALSE, &no_tags);
	} else
	{
		inbound_privmsg (dcc->serv, dcc->nick, "", line, FALSE, &no_tags);
	}
	g_free (line);
	return 0;
}

static gboolean
dcc_read_chat (GIOChannel *source, GIOCondition condition, struct DCC *dcc)
{
	int i, len, dead;
	char portbuf[32];
	char lbuf[2050];

	while (1)
	{
		if (dcc->throttled)
		{
			fe_input_remove (dcc->iotag);
			dcc->iotag = 0;
			return FALSE;
		}

		if (!dcc->iotag)
			dcc->iotag = fe_input_add (dcc->sok, FIA_READ|FIA_EX, dcc_read_chat, dcc);

		len = recv (dcc->sok, lbuf, sizeof (lbuf) - 2, 0);
		if (len < 1)
		{
			if (len < 0)
			{
				if (would_block ())
					return TRUE;
			}
			sprintf (portbuf, "%d", dcc->port);
			EMIT_SIGNAL (XP_TE_DCCCHATF, dcc->serv->front_session, dcc->nick,
							 net_ip (dcc->addr), portbuf,
							 errorstring ((len < 0) ? sock_error () : 0), 0);
			dcc_close (dcc, STAT_FAILED, FALSE);
			return TRUE;
		}
		i = 0;
		lbuf[len] = 0;
		while (i < len)
		{
			switch (lbuf[i])
			{
			case '\r':
				break;
			case '\n':
				dcc->dccchat->linebuf[dcc->dccchat->pos] = 0;
				dead = dcc_chat_line (dcc, dcc->dccchat->linebuf);

				if (dead || !dcc->dccchat) /* the dcc has been closed, don't use (DCC *)! */
					return TRUE;

				dcc->pos += dcc->dccchat->pos;
				dcc->dccchat->pos = 0;
				fe_dcc_update (dcc);
				break;
			default:
				dcc->dccchat->linebuf[dcc->dccchat->pos] = lbuf[i];
				if (dcc->dccchat->pos < (sizeof (dcc->dccchat->linebuf) - 1))
					dcc->dccchat->pos++;
			}
			i++;
		}
	}
}

static void
dcc_calc_average_cps (struct DCC *dcc)
{
	time_t sec;

	sec = time (0) - dcc->starttime;
	if (sec < 1)
		sec = 1;
	if (dcc->type == TYPE_SEND)
		dcc->cps = (dcc->ack - dcc->resumable) / sec;
	else
		dcc->cps = (dcc->pos - dcc->resumable) / sec;
}

static void
dcc_send_ack (struct DCC *dcc)
{
	/* send in 32-bit big endian */
	guint32 pos = htonl (dcc->pos & 0xffffffff);
	send (dcc->sok, (char *) &pos, 4, 0);
}

static gboolean
dcc_read (GIOChannel *source, GIOCondition condition, struct DCC *dcc)
{
	char *old;
	char buf[4096];
	int n;
	gboolean need_ack = FALSE;

	if (dcc->fp == -1)
	{

		/* try to create the download dir (even if it exists, no harm) */
		g_mkdir (prefs.hex_dcc_dir, 0700);

		if (dcc->resumable)
		{
			gchar *filename_fs = g_filename_from_utf8(dcc->destfile, -1, NULL, NULL, NULL);
			dcc->fp = g_open(dcc->destfile, O_WRONLY | O_APPEND | OFLAGS, 0);
			g_free (filename_fs);

			dcc->pos = dcc->resumable;
			dcc->ack = dcc->resumable;
		}
		else
		{
			gchar *filename_fs;

			if (g_access (dcc->destfile, F_OK) == 0)
			{
				n = 0;
				do
				{
					n++;
					g_snprintf (buf, sizeof (buf), "%s.%d", dcc->destfile, n);
				}
				while (g_access (buf, F_OK) == 0);

				old = dcc->destfile;
				dcc->destfile = g_strdup (buf);

				EMIT_SIGNAL (XP_TE_DCCRENAME, dcc->serv->front_session,
								 old, dcc->destfile, NULL, NULL, 0);
				g_free (old);
			}

			filename_fs = g_filename_from_utf8 (dcc->destfile, -1, NULL, NULL, NULL);
			dcc->fp = g_open (filename_fs, OFLAGS | O_TRUNC | O_WRONLY | O_CREAT, prefs.hex_dcc_permissions);
			g_free (filename_fs);
		}
	}
	if (dcc->fp == -1)
	{
		/* the last executed function is open(), errno should be valid */
		EMIT_SIGNAL (XP_TE_DCCFILEERR, dcc->serv->front_session, dcc->destfile,
						 errorstring (errno), NULL, NULL, 0);
		dcc_close (dcc, STAT_FAILED, FALSE);
		return TRUE;
	}
	while (1)
	{
		if (dcc->throttled)
		{
			if (need_ack)
				dcc_send_ack (dcc);

			fe_input_remove (dcc->iotag);
			dcc->iotag = 0;
			return FALSE;
		}

		if (!dcc->iotag)
			dcc->iotag = fe_input_add (dcc->sok, FIA_READ|FIA_EX, dcc_read, dcc);

		n = recv (dcc->sok, buf, sizeof (buf), 0);
		if (n < 1)
		{
			if (n < 0)
			{
				if (would_block ())
				{
					if (need_ack)
						dcc_send_ack (dcc);
					return TRUE;
				}
			}
			EMIT_SIGNAL (XP_TE_DCCRECVERR, dcc->serv->front_session, dcc->file,
							 dcc->destfile, dcc->nick,
							 errorstring ((n < 0) ? sock_error () : 0), 0);
			/* send ack here? but the socket is dead */
			/*if (need_ack)
				dcc_send_ack (dcc);*/
			dcc_close (dcc, STAT_FAILED, FALSE);
			return TRUE;
		}

		if (write (dcc->fp, buf, n) == -1) /* could be out of hdd space */
		{
			EMIT_SIGNAL (XP_TE_DCCRECVERR, dcc->serv->front_session, dcc->file,
							 dcc->destfile, dcc->nick, errorstring (errno), 0);
			if (need_ack)
				dcc_send_ack (dcc);
			dcc_close (dcc, STAT_FAILED, FALSE);
			return TRUE;
		}

		dcc->lasttime = time (0);
		dcc->pos += n;
		need_ack = TRUE;	/* send ack when we're done recv()ing */

		if (dcc->pos >= dcc->size)
		{
			dcc_send_ack (dcc);
			dcc_close (dcc, STAT_DONE, FALSE);
			dcc_calc_average_cps (dcc);	/* this must be done _after_ dcc_close, or dcc_remove_from_sum will see the wrong value in dcc->cps */
			/* cppcheck-suppress deallocuse */
			sprintf (buf, "%" G_GINT64_FORMAT, dcc->cps);
			EMIT_SIGNAL (XP_TE_DCCRECVCOMP, dcc->serv->front_session,
							 dcc->file, dcc->destfile, dcc->nick, buf, 0);
			return TRUE;
		}
	}
}

static void
dcc_open_query (server *serv, char *nick)
{
	if (prefs.hex_gui_autoopen_dialog)
		open_query (serv, nick, FALSE);
}

static gboolean
dcc_did_connect (GIOChannel *source, GIOCondition condition, struct DCC *dcc)
{
	int er;
	
#ifdef WIN32
	if (condition & G_IO_ERR)
	{
		int len;

		/* find the last errno for this socket */
		len = sizeof (er);
		getsockopt (dcc->sok, SOL_SOCKET, SO_ERROR, (char *)&er, &len);
		EMIT_SIGNAL (XP_TE_DCCCONFAIL, dcc->serv->front_session,
						 dcctypes[dcc->type], dcc->nick, errorstring (er),
						 NULL, 0);
		dcc->dccstat = STAT_FAILED;
		fe_dcc_update (dcc);
		return FALSE;
	}

#else
	struct sockaddr_in addr;

	memset (&addr, 0, sizeof (addr));
	addr.sin_port = htons (dcc->port);
	addr.sin_family = AF_INET;
	addr.sin_addr.s_addr = htonl (dcc->addr);

	/* check if it's already connected; This always fails on winXP */
	if (connect (dcc->sok, (struct sockaddr *) &addr, sizeof (addr)) != 0)
	{
		er = sock_error ();
		if (er != EISCONN)
		{
			EMIT_SIGNAL (XP_TE_DCCCONFAIL, dcc->serv->front_session,
							 dcctypes[dcc->type], dcc->nick, errorstring (er),
							 NULL, 0);
			dcc->dccstat = STAT_FAILED;
			fe_dcc_update (dcc);
			return FALSE;
		}
	}
#endif
	
	return TRUE;
}

static gboolean
dcc_connect_finished (GIOChannel *source, GIOCondition condition, struct DCC *dcc)
{
	char host[128];

	if (dcc->iotag)
	{
		fe_input_remove (dcc->iotag);
		dcc->iotag = 0;
	}

	if (!dcc_did_connect (source, condition, dcc))
		return TRUE;

	dcc->dccstat = STAT_ACTIVE;
	g_snprintf (host, sizeof host, "%s:%d", net_ip (dcc->addr), dcc->port);

	switch (dcc->type)
	{
	case TYPE_RECV:
		dcc->iotag = fe_input_add (dcc->sok, FIA_READ|FIA_EX, dcc_read, dcc);
		EMIT_SIGNAL (XP_TE_DCCCONRECV, dcc->serv->front_session,
						 dcc->nick, host, dcc->file, NULL, 0);
		break;
	case TYPE_SEND:
		/* passive send */
		dcc->fastsend = prefs.hex_dcc_fast_send;
		if (dcc->fastsend)
			dcc->wiotag = fe_input_add (dcc->sok, FIA_WRITE, dcc_send_data, dcc);
		dcc->iotag = fe_input_add (dcc->sok, FIA_READ|FIA_EX, dcc_read_ack, dcc);
		dcc_send_data (NULL, 0, (gpointer)dcc);
		EMIT_SIGNAL (XP_TE_DCCCONSEND, dcc->serv->front_session,
						 dcc->nick, host, dcc->file, NULL, 0);
		break;
	case TYPE_CHATSEND:	/* pchat */
		dcc_open_query (dcc->serv, dcc->nick);
	case TYPE_CHATRECV:	/* normal chat */
		dcc->iotag = fe_input_add (dcc->sok, FIA_READ|FIA_EX, dcc_read_chat, dcc);
		dcc->dccchat = g_new0 (struct dcc_chat, 1);
		EMIT_SIGNAL (XP_TE_DCCCONCHAT, dcc->serv->front_session,
						 dcc->nick, host, NULL, NULL, 0);
		break;
	}
	dcc->starttime = time (0);
	dcc->lasttime = dcc->starttime;
	fe_dcc_update (dcc);

	return TRUE;
}

static gboolean
read_proxy (struct DCC *dcc)
{
	struct proxy_state *proxy = dcc->proxy;
	while (proxy->bufferused < proxy->buffersize)
	{
		int ret = recv (dcc->sok, &proxy->buffer[proxy->bufferused],
						proxy->buffersize - proxy->bufferused, 0);
		if (ret > 0)
			proxy->bufferused += ret;
		else
		{
			if (would_block ())
				return FALSE;
			else
			{
				dcc->dccstat = STAT_FAILED;
				fe_dcc_update (dcc);
				if (dcc->iotag)
				{
					fe_input_remove (dcc->iotag);
					dcc->iotag = 0;
				}
				return FALSE;
			}
		}
	}
	return TRUE;
}

static gboolean
write_proxy (struct DCC *dcc)
{
	struct proxy_state *proxy = dcc->proxy;
	while (proxy->bufferused < proxy->buffersize)
	{
		int ret = send (dcc->sok, &proxy->buffer[proxy->bufferused],
						proxy->buffersize - proxy->bufferused, 0);
		if (ret >= 0)
			proxy->bufferused += ret;
		else
		{
			if (would_block ())
				return FALSE;
			else
			{
				dcc->dccstat = STAT_FAILED;
				fe_dcc_update (dcc);
				if (dcc->wiotag)
				{
					fe_input_remove (dcc->wiotag);
					dcc->wiotag = 0;
				}
				return FALSE;
			}
		}
	}
	return TRUE;
}

static gboolean
proxy_read_line (struct DCC *dcc)
{
	struct proxy_state *proxy = dcc->proxy;
	while (1)
	{
		proxy->buffersize = proxy->bufferused + 1;
		if (!read_proxy (dcc))
			return FALSE;
		if (proxy->buffer[proxy->bufferused - 1] == '\n'
			|| proxy->bufferused == MAX_PROXY_BUFFER)
		{
			proxy->buffer[proxy->bufferused - 1] = 0;
			return TRUE;
		}
	}
}

static gboolean
dcc_wingate_proxy_traverse (GIOChannel *source, GIOCondition condition, struct DCC *dcc)
{
	struct proxy_state *proxy = dcc->proxy;
	if (proxy->phase == 0)
	{
		proxy->buffersize = g_snprintf ((char*) proxy->buffer, MAX_PROXY_BUFFER,
										"%s %d\r\n", net_ip(dcc->addr),
										dcc->port);
		proxy->bufferused = 0;
		dcc->wiotag = fe_input_add (dcc->sok, FIA_WRITE|FIA_EX,
									dcc_wingate_proxy_traverse, dcc);
		++proxy->phase;
	}
	if (proxy->phase == 1)
	{
		if (!read_proxy (dcc))
			return TRUE;
		fe_input_remove (dcc->wiotag);
		dcc->wiotag = 0;
		dcc_connect_finished (source, 0, dcc);
	}
	return TRUE;
}

struct sock_connect
{
	char version;
	char type;
	guint16 port;
	guint32 address;
	char username[10];
};
static gboolean
dcc_socks_proxy_traverse (GIOChannel *source, GIOCondition condition, struct DCC *dcc)
{
	struct proxy_state *proxy = dcc->proxy;

	if (proxy->phase == 0)
	{
		struct sock_connect sc;
		sc.version = 4;
		sc.type = 1;
		sc.port = htons (dcc->port);
		sc.address = htonl (dcc->addr);
		strncpy (sc.username, prefs.hex_irc_user_name, 9);
		memcpy (proxy->buffer, &sc, sizeof (sc));
		proxy->buffersize = 8 + strlen (sc.username) + 1;
		proxy->bufferused = 0;
		dcc->wiotag = fe_input_add (dcc->sok, FIA_WRITE|FIA_EX,
									dcc_socks_proxy_traverse, dcc);
		++proxy->phase;
	}

	if (proxy->phase == 1)
	{
		if (!write_proxy (dcc))
			return TRUE;
		fe_input_remove (dcc->wiotag);
		dcc->wiotag = 0;
		proxy->bufferused = 0;
		proxy->buffersize = 8;
		dcc->iotag = fe_input_add (dcc->sok, FIA_READ|FIA_EX,
									dcc_socks_proxy_traverse, dcc);
		++proxy->phase;
	}

	if (proxy->phase == 2)
	{
		if (!read_proxy (dcc))
			return TRUE;
		fe_input_remove (dcc->iotag);
		dcc->iotag = 0;
		if (proxy->buffer[1] == 90)
			dcc_connect_finished (source, 0, dcc);
		else