family_oservice.c

Linux下的多协议即时通讯程序源代码

/*
 * Purple's oscar protocol plugin
 * This file is the legal property of its developers.
 * Please see the AUTHORS file distributed alongside this file.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
*/

/*
 * Family 0x0001 - This is a very special group.  All connections support
 * this group, as it does some particularly good things (like rate limiting).
 */

#include "oscar.h"

#include "cipher.h"

/* Subtype 0x0002 - Client Online */
void
aim_clientready(OscarData *od, FlapConnection *conn)
{
	FlapFrame *frame;
	aim_snacid_t snacid;
	GSList *cur;

	frame = flap_frame_new(od, 0x02, 1152);

	snacid = aim_cachesnac(od, 0x0001, 0x0002, 0x0000, NULL, 0);
	aim_putsnac(&frame->data, 0x0001, 0x0002, 0x0000, snacid);

	/*
	 * Send only the tool versions that the server cares about (that it
	 * marked as supporting in the server ready SNAC).
	 */
	for (cur = conn->groups; cur != NULL; cur = cur->next)
	{
		aim_module_t *mod;

		if ((mod = aim__findmodulebygroup(od, GPOINTER_TO_UINT(cur->data))))
		{
			byte_stream_put16(&frame->data, mod->family);
			byte_stream_put16(&frame->data, mod->version);
			byte_stream_put16(&frame->data, mod->toolid);
			byte_stream_put16(&frame->data, mod->toolversion);
		}
	}

	flap_connection_send(conn, frame);
}

/*
 * Subtype 0x0003 - Host Online
 *
 * See comments in conn.c about how the group associations are supposed
 * to work, and how they really work.
 *
 * This info probably doesn't even need to make it to the client.
 *
 * We don't actually call the client here.  This starts off the connection
 * initialization routine required by all AIM connections.  The next time
 * the client is called is the CONNINITDONE callback, which should be
 * shortly after the rate information is acknowledged.
 *
 */
static int
hostonline(OscarData *od, FlapConnection *conn, aim_module_t *mod, FlapFrame *frame, aim_modsnac_t *snac, ByteStream *bs)
{
	int group;

	while (byte_stream_empty(bs))
	{
		group = byte_stream_get16(bs);
		conn->groups = g_slist_prepend(conn->groups, GUINT_TO_POINTER(group));
	}

	/*
	 * Next step is in the Host Versions handler.
	 *
	 * Note that we must send this before we request rates, since
	 * the format of the rate information depends on the versions we
	 * give it.
	 *
	 */
	aim_srv_setversions(od, conn);

	return 1;
}

/* Subtype 0x0004 - Service request */
void
aim_srv_requestnew(OscarData *od, guint16 serviceid)
{
	FlapConnection *conn;

	conn = flap_connection_findbygroup(od, SNAC_FAMILY_BOS);
	if(!conn)
		return;

	aim_genericreq_s(od, conn, 0x0001, 0x0004, &serviceid);
}

/*
 * Join a room of name roomname.  This is the first step to joining an
 * already created room.  It's basically a Service Request for
 * family 0x000e, with a little added on to specify the exchange and room
 * name.
 */
int
aim_chat_join(OscarData *od, guint16 exchange, const char *roomname, guint16 instance)
{
	FlapConnection *conn;
	FlapFrame *frame;
	aim_snacid_t snacid;
	GSList *tlvlist = NULL;
	struct chatsnacinfo csi;

	conn = flap_connection_findbygroup(od, SNAC_FAMILY_BOS);
	if (!conn || !roomname || !strlen(roomname))
		return -EINVAL;

	frame = flap_frame_new(od, 0x02, 512);

	memset(&csi, 0, sizeof(csi));
	csi.exchange = exchange;
	strncpy(csi.name, roomname, sizeof(csi.name));
	csi.instance = instance;

	snacid = aim_cachesnac(od, 0x0001, 0x0004, 0x0000, &csi, sizeof(csi));
	aim_putsnac(&frame->data, 0x0001, 0x0004, 0x0000, snacid);

	/*
	 * Requesting service chat (0x000e)
	 */
	byte_stream_put16(&frame->data, 0x000e);

	aim_tlvlist_add_chatroom(&tlvlist, 0x0001, exchange, roomname, instance);
	aim_tlvlist_write(&frame->data, &tlvlist);
	aim_tlvlist_free(tlvlist);

	flap_connection_send(conn, frame);

	return 0;
}

/* Subtype 0x0005 - Redirect */
static int
redirect(OscarData *od, FlapConnection *conn, aim_module_t *mod, FlapFrame *frame, aim_modsnac_t *snac, ByteStream *bs)
{
	struct aim_redirect_data redir;
	aim_rxcallback_t userfunc;
	GSList *tlvlist;
	aim_snac_t *origsnac = NULL;
	int ret = 0;

	memset(&redir, 0, sizeof(redir));

	tlvlist = aim_tlvlist_read(bs);

	if (!aim_tlv_gettlv(tlvlist, 0x000d, 1) ||
			!aim_tlv_gettlv(tlvlist, 0x0005, 1) ||
			!aim_tlv_gettlv(tlvlist, 0x0006, 1)) {
		aim_tlvlist_free(tlvlist);
		return 0;
	}

	redir.group = aim_tlv_get16(tlvlist, 0x000d, 1);
	redir.ip = aim_tlv_getstr(tlvlist, 0x0005, 1);
	redir.cookielen = aim_tlv_gettlv(tlvlist, 0x0006, 1)->length;
	redir.cookie = (guchar *)aim_tlv_getstr(tlvlist, 0x0006, 1);

	/* Fetch original SNAC so we can get csi if needed */
	origsnac = aim_remsnac(od, snac->id);

	if ((redir.group == SNAC_FAMILY_CHAT) && origsnac) {
		struct chatsnacinfo *csi = (struct chatsnacinfo *)origsnac->data;

		redir.chat.exchange = csi->exchange;
		redir.chat.room = csi->name;
		redir.chat.instance = csi->instance;
	}

	if ((userfunc = aim_callhandler(od, snac->family, snac->subtype)))
		ret = userfunc(od, conn, frame, &redir);

	g_free((void *)redir.ip);
	g_free((void *)redir.cookie);

	if (origsnac)
		g_free(origsnac->data);
	g_free(origsnac);

	aim_tlvlist_free(tlvlist);

	return ret;
}

/* Subtype 0x0006 - Request Rate Information. */
void
aim_srv_reqrates(OscarData *od, FlapConnection *conn)
{
	aim_genericreq_n_snacid(od, conn, 0x0001, 0x0006);
}

/*
 * OSCAR defines several 'rate classes'.  Each class has separate
 * rate limiting properties (limit level, alert level, disconnect
 * level, etc), and a set of SNAC family/type pairs associated with
 * it.  The rate classes, their limiting properties, and the definitions
 * of which SNACs belong to which class are defined in the
 * Rate Response packet at login to each host.
 *
 * Logically, all rate offenses within one class count against further
 * offenses for other SNACs in the same class (ie, sending messages
 * too fast will limit the number of user info requests you can send,
 * since those two SNACs are in the same rate class).
 *
 * Since the rate classes are defined dynamically at login, the values
 * below may change. But they seem to be fairly constant.
 *
 * Currently, BOS defines five rate classes, with the commonly used
 * members as follows...
 *
 *  Rate class 0x0001:
 *	- Everything thats not in any of the other classes
 *
 *  Rate class 0x0002:
 *	- Buddy list add/remove
 *	- Permit list add/remove
 *	- Deny list add/remove
 *
 *  Rate class 0x0003:
 *	- User information requests
 *	- Outgoing ICBMs
 *
 *  Rate class 0x0004:
 *	- A few unknowns: 2/9, 2/b, and f/2
 *
 *  Rate class 0x0005:
 *	- Chat room create
 *	- Outgoing chat ICBMs
 *
 * The only other thing of note is that class 5 (chat) has slightly looser
 * limiting properties than class 3 (normal messages).  But thats just a
 * small bit of trivia for you.
 *
 * The last thing that needs to be learned about the rate limiting
 * system is how the actual numbers relate to the passing of time.  This
 * seems to be a big mystery.
 *
 * See joscar's javadoc for the RateClassInfo class for a great
 * explanation.  You might be able to find it at
 * http://dscoder.com/RateClassInfo.html
 */

static struct rateclass *
rateclass_find(GSList *rateclasses, guint16 id)
{
	GSList *tmp;

	for (tmp = rateclasses; tmp != NULL; tmp = tmp->next)
	{
		struct rateclass *rateclass;
		rateclass = tmp->data;
		if (rateclass->classid == id)
			return rateclass;
	}

	return NULL;
}

/* Subtype 0x0007 - Rate Parameters */
static int
rateresp(OscarData *od, FlapConnection *conn, aim_module_t *mod, FlapFrame *frame, aim_modsnac_t *snac, ByteStream *bs)
{
	guint16 numclasses, i;
	aim_rxcallback_t userfunc;

	/*
	 * First are the parameters for each rate class.
	 */
	numclasses = byte_stream_get16(bs);
	for (i = 0; i < numclasses; i++)
	{
		struct rateclass *rateclass;

		rateclass = g_new0(struct rateclass, 1);

		rateclass->classid = byte_stream_get16(bs);
		rateclass->windowsize = byte_stream_get32(bs);
		rateclass->clear = byte_stream_get32(bs);
		rateclass->alert = byte_stream_get32(bs);
		rateclass->limit = byte_stream_get32(bs);
		rateclass->disconnect = byte_stream_get32(bs);
		rateclass->current = byte_stream_get32(bs);
		rateclass->max = byte_stream_get32(bs);

		/*
		 * The server will send an extra five bytes of parameters
		 * depending on the version we advertised in 1/17.  If we
		 * didn't send 1/17 (evil!), then this will crash and you
		 * die, as it will default to the old version but we have
		 * the new version hardcoded here.
		 */
		if (mod->version >= 3)
			byte_stream_getrawbuf(bs, rateclass->unknown, sizeof(rateclass->unknown));

		rateclass->members = g_hash_table_new(g_direct_hash, g_direct_equal);
		rateclass->last.tv_sec = 0;
		rateclass->last.tv_usec = 0;
		conn->rateclasses = g_slist_prepend(conn->rateclasses, rateclass);
	}
	conn->rateclasses = g_slist_reverse(conn->rateclasses);

	/*
	 * Then the members of each class.
	 */
	for (i = 0; i < numclasses; i++)
	{
		guint16 classid, count;
		struct rateclass *rateclass;
		int j;

		classid = byte_stream_get16(bs);
		count = byte_stream_get16(bs);

		rateclass = rateclass_find(conn->rateclasses, classid);

		for (j = 0; j < count; j++)
		{
			guint16 group, subtype;

			group = byte_stream_get16(bs);
			subtype = byte_stream_get16(bs);

			if (rateclass != NULL)
				g_hash_table_insert(rateclass->members,
						GUINT_TO_POINTER((group << 16) + subtype),
						GUINT_TO_POINTER(TRUE));
		}
	}

	/*
	 * We don't pass the rate information up to the client, as it really
	 * doesn't care.  The information is stored in the connection, however
	 * so that we can do rate limiting management when sending SNACs.
	 */

	/*
	 * Last step in the conn init procedure is to acknowledge that we
	 * agree to these draconian limitations.
	 */
	aim_srv_rates_addparam(od, conn);

	/*
	 * Finally, tell the client it's ready to go...
	 */
	if ((userfunc = aim_callhandler(od, AIM_CB_FAM_SPECIAL, AIM_CB_SPECIAL_CONNINITDONE)))
		userfunc(od, conn, frame);