simple.c

Linux下的多协议即时通讯程序源代码

	if(purple_circ_buffer_get_max_read(sip->txbuf) > 0)
		purple_circ_buffer_append(sip->txbuf, "\r\n", 2);

	purple_circ_buffer_append(sip->txbuf, buf, strlen(buf));
}

static void sendout_pkt(PurpleConnection *gc, const char *buf) {
	struct simple_account_data *sip = gc->proto_data;
	time_t currtime = time(NULL);
	int writelen = strlen(buf);

	purple_debug(PURPLE_DEBUG_MISC, "simple", "\n\nsending - %s\n######\n%s\n######\n\n", ctime(&currtime), buf);
	if(sip->udp) {
		if(sendto(sip->fd, buf, writelen, 0, (struct sockaddr*)&sip->serveraddr, sizeof(struct sockaddr_in)) < writelen) {
			purple_debug_info("simple", "could not send packet\n");
		}
	} else {
		int ret;
		if(sip->fd < 0) {
			sendlater(gc, buf);
			return;
		}

		if(sip->tx_handler) {
			ret = -1;
			errno = EAGAIN;
		} else
			ret = write(sip->fd, buf, writelen);

		if (ret < 0 && errno == EAGAIN)
			ret = 0;
		else if(ret <= 0) { /* XXX: When does this happen legitimately? */
			sendlater(gc, buf);
			return;
		}

		if (ret < writelen) {
			if(!sip->tx_handler)
				sip->tx_handler = purple_input_add(sip->fd,
					PURPLE_INPUT_WRITE, simple_canwrite_cb,
					gc);

			/* XXX: is it OK to do this? You might get part of a request sent
			   with part of another. */
			if(sip->txbuf->bufused > 0)
				purple_circ_buffer_append(sip->txbuf, "\r\n", 2);

			purple_circ_buffer_append(sip->txbuf, buf + ret,
				writelen - ret);
		}
	}
}

static int simple_send_raw(PurpleConnection *gc, const char *buf, int len)
{
	sendout_pkt(gc, buf);
	return len;
}

static void sendout_sipmsg(struct simple_account_data *sip, struct sipmsg *msg) {
	GSList *tmp = msg->headers;
	gchar *name;
	gchar *value;
	GString *outstr = g_string_new("");
	g_string_append_printf(outstr, "%s %s SIP/2.0\r\n", msg->method, msg->target);
	while(tmp) {
		name = ((struct siphdrelement*) (tmp->data))->name;
		value = ((struct siphdrelement*) (tmp->data))->value;
		g_string_append_printf(outstr, "%s: %s\r\n", name, value);
		tmp = g_slist_next(tmp);
	}
	g_string_append_printf(outstr, "\r\n%s", msg->body ? msg->body : "");
	sendout_pkt(sip->gc, outstr->str);
	g_string_free(outstr, TRUE);
}

static void send_sip_response(PurpleConnection *gc, struct sipmsg *msg, int code,
		const char *text, const char *body) {
	GSList *tmp = msg->headers;
	gchar *name;
	gchar *value;
	GString *outstr = g_string_new("");

	/* When sending the acknowlegements and errors, the content length from the original
	   message is still here, but there is no body; we need to make sure we're sending the
	   correct content length */
	sipmsg_remove_header(msg, "Content-Length");
	if(body) {
		gchar len[12];
		sprintf(len, "%" G_GSIZE_FORMAT , strlen(body));
		sipmsg_add_header(msg, "Content-Length", len);
	}
	else
		sipmsg_add_header(msg, "Content-Length", "0");
	g_string_append_printf(outstr, "SIP/2.0 %d %s\r\n", code, text);
	while(tmp) {
		name = ((struct siphdrelement*) (tmp->data))->name;
		value = ((struct siphdrelement*) (tmp->data))->value;

		g_string_append_printf(outstr, "%s: %s\r\n", name, value);
		tmp = g_slist_next(tmp);
	}
	g_string_append_printf(outstr, "\r\n%s", body ? body : "");
	sendout_pkt(gc, outstr->str);
	g_string_free(outstr, TRUE);
}

static void transactions_remove(struct simple_account_data *sip, struct transaction *trans) {
	if(trans->msg) sipmsg_free(trans->msg);
	sip->transactions = g_slist_remove(sip->transactions, trans);
	g_free(trans);
}

static void transactions_add_buf(struct simple_account_data *sip, const gchar *buf, void *callback) {
	struct transaction *trans = g_new0(struct transaction, 1);
	trans->time = time(NULL);
	trans->msg = sipmsg_parse_msg(buf);
	trans->cseq = sipmsg_find_header(trans->msg, "CSeq");
	trans->callback = callback;
	sip->transactions = g_slist_append(sip->transactions, trans);
}

static struct transaction *transactions_find(struct simple_account_data *sip, struct sipmsg *msg) {
	struct transaction *trans;
	GSList *transactions = sip->transactions;
	gchar *cseq = sipmsg_find_header(msg, "CSeq");

	if (cseq) {
		while(transactions) {
			trans = transactions->data;
			if(!strcmp(trans->cseq, cseq)) {
				return trans;
			}
			transactions = transactions->next;
		}
	} else {
		purple_debug(PURPLE_DEBUG_MISC, "simple", "Received message contains no CSeq header.\n");
	}

	return NULL;
}

static void send_sip_request(PurpleConnection *gc, const gchar *method,
		const gchar *url, const gchar *to, const gchar *addheaders,
		const gchar *body, struct sip_dialog *dialog, TransCallback tc) {
	struct simple_account_data *sip = gc->proto_data;
	char *callid = dialog ? g_strdup(dialog->callid) : gencallid();
	char *auth = NULL;
	const char *addh = "";
	gchar *branch = genbranch();
	gchar *tag = NULL;
	char *buf;

	if(!strcmp(method, "REGISTER")) {
		if(sip->regcallid) {
			g_free(callid);
			callid = g_strdup(sip->regcallid);
		}
		else sip->regcallid = g_strdup(callid);
	}

	if(addheaders) addh = addheaders;
	if(sip->registrar.type && !strcmp(method, "REGISTER")) {
		buf = auth_header(sip, &sip->registrar, method, url);
		auth = g_strdup_printf("Authorization: %s\r\n", buf);
		g_free(buf);
		purple_debug(PURPLE_DEBUG_MISC, "simple", "header %s", auth);
	} else if(sip->proxy.type && strcmp(method, "REGISTER")) {
		buf = auth_header(sip, &sip->proxy, method, url);
		auth = g_strdup_printf("Proxy-Authorization: %s\r\n", buf);
		g_free(buf);
		purple_debug(PURPLE_DEBUG_MISC, "simple", "header %s", auth);
	}

	if (!dialog)
		tag = gentag();

	buf = g_strdup_printf("%s %s SIP/2.0\r\n"
			"Via: SIP/2.0/%s %s:%d;branch=%s\r\n"
			/* Don't know what epid is, but LCS wants it */
			"From: <sip:%s@%s>;tag=%s;epid=1234567890\r\n"
			"To: <%s>%s%s\r\n"
			"Max-Forwards: 10\r\n"
			"CSeq: %d %s\r\n"
			"User-Agent: Purple/" VERSION "\r\n"
			"Call-ID: %s\r\n"
			"%s%s"
			"Content-Length: %" G_GSIZE_FORMAT "\r\n\r\n%s",
			method,
			url,
			sip->udp ? "UDP" : "TCP",
			purple_network_get_my_ip(-1),
			sip->listenport,
			branch,
			sip->username,
			sip->servername,
			dialog ? dialog->ourtag : tag,
			to,
			dialog ? ";tag=" : "",
			dialog ? dialog->theirtag : "",
			++sip->cseq,
			method,
			callid,
			auth ? auth : "",
			addh,
			strlen(body),
			body);

	g_free(tag);
	g_free(auth);
	g_free(branch);
	g_free(callid);

	/* add to ongoing transactions */

	transactions_add_buf(sip, buf, tc);

	sendout_pkt(gc, buf);

	g_free(buf);
}

static char *get_contact(struct simple_account_data  *sip) {
	return g_strdup_printf("<sip:%s@%s:%d;transport=%s>;methods=\"MESSAGE, SUBSCRIBE, NOTIFY\"", sip->username, purple_network_get_my_ip(-1), sip->listenport, sip->udp ? "udp" : "tcp");
}

static void do_register_exp(struct simple_account_data *sip, int expire) {
	char *uri = g_strdup_printf("sip:%s", sip->servername);
	char *to = g_strdup_printf("sip:%s@%s", sip->username, sip->servername);
	char *contact = get_contact(sip);
	char *hdr = g_strdup_printf("Contact: %s\r\nExpires: %d\r\n", contact, expire);
	g_free(contact);

	sip->registerstatus = 1;

	if(expire) {
		sip->reregister = time(NULL) + expire - 50;
	} else {
		sip->reregister = time(NULL) + 600;
	}

	send_sip_request(sip->gc, "REGISTER", uri, to, hdr, "", NULL,
		process_register_response);

	g_free(hdr);
	g_free(uri);
	g_free(to);
}

static void do_register(struct simple_account_data *sip) {
	do_register_exp(sip, sip->registerexpire);
}

static gchar *parse_from(const gchar *hdr) {
	gchar *from;
	const gchar *tmp, *tmp2 = hdr;

	if(!hdr) return NULL;
	purple_debug_info("simple", "parsing address out of %s\n", hdr);
	tmp = strchr(hdr, '<');

	/* i hate the different SIP UA behaviours... */
	if(tmp) { /* sip address in <...> */
		tmp2 = tmp + 1;
		tmp = strchr(tmp2, '>');
		if(tmp) {
			from = g_strndup(tmp2, tmp - tmp2);
		} else {
			purple_debug_info("simple", "found < without > in From\n");
			return NULL;
		}
	} else {
		tmp = strchr(tmp2, ';');
		if(tmp) {
			from = g_strndup(tmp2, tmp - tmp2);
		} else {
			from = g_strdup(tmp2);
		}
	}
	purple_debug_info("simple", "got %s\n", from);
	return from;
}

static gboolean process_subscribe_response(struct simple_account_data *sip, struct sipmsg *msg, struct transaction *tc) {
	gchar *to;

	if(msg->response == 200 || msg->response == 202) {
		return TRUE;
	}

	to = parse_from(sipmsg_find_header(tc->msg, "To")); /* cant be NULL since it is our own msg */

	/* we can not subscribe -> user is offline (TODO unknown status?) */

	purple_prpl_got_user_status(sip->account, to, "offline", NULL);
	g_free(to);
	return TRUE;
}

static void simple_subscribe(struct simple_account_data *sip, struct simple_buddy *buddy) {
	gchar *contact = "Expires: 1200\r\nAccept: application/pidf+xml, application/xpidf+xml\r\nEvent: presence\r\n";
	gchar *to;
	gchar *tmp;

	if(strstr(buddy->name, "sip:"))
		to = g_strdup(buddy->name);
	else
		to = g_strdup_printf("sip:%s", buddy->name);

	tmp = get_contact(sip);
	contact = g_strdup_printf("%sContact: %s\r\n", contact, tmp);
	g_free(tmp);

	/* subscribe to buddy presence
	 * we dont need to know the status so we do not need a callback */

	send_sip_request(sip->gc, "SUBSCRIBE", to, to, contact, "", NULL,
		process_subscribe_response);

	g_free(to);
	g_free(contact);

	/* resubscribe before subscription expires */
	/* add some jitter */
	buddy->resubscribe = time(NULL)+1140+(rand()%50);
}

static gboolean simple_add_lcs_contacts(struct simple_account_data *sip, struct sipmsg *msg, struct transaction *tc) {
	gchar *tmp;
	xmlnode *item, *group, *isc;
	const char *name_group;
	PurpleBuddy *b;
	PurpleGroup *g = NULL;
	struct simple_buddy *bs;
	int len = msg->bodylen;


	tmp = sipmsg_find_header(msg, "Event");
	if(tmp && !strncmp(tmp, "vnd-microsoft-roaming-contacts", 30)){

		purple_debug_info("simple", "simple_add_lcs_contacts->%s-%d\n", msg->body, len);
		/*Convert the contact from XML to Purple Buddies*/
		isc = xmlnode_from_str(msg->body, len);

		/* ToDo. Find for all groups */
		if ((group = xmlnode_get_child(isc, "group"))) {
			name_group = xmlnode_get_attrib(group, "name");
			purple_debug_info("simple", "name_group->%s\n", name_group);
			g = purple_find_group(name_group);
			if(!g)
				g = purple_group_new(name_group);
		}

		if (!g) {
			g = purple_find_group("Buddies");
			if(!g)
				g = purple_group_new("Buddies");
		}

		for(item = xmlnode_get_child(isc, "contact"); item; item = xmlnode_get_next_twin(item))
		{
			const char *uri, *name, *groups;
			char *buddy_name;
			uri = xmlnode_get_attrib(item, "uri");
			name = xmlnode_get_attrib(item, "name");
			groups = xmlnode_get_attrib(item, "groups");
			purple_debug_info("simple", "URI->%s\n", uri);

			buddy_name = g_strdup_printf("sip:%s", uri);

			b = purple_find_buddy(sip->account, buddy_name);
			if(!b){
				b = purple_buddy_new(sip->account, buddy_name, uri);
			}
			g_free(buddy_name);

			purple_blist_add_buddy(b, NULL, g, NULL);
			purple_blist_alias_buddy(b, uri);
			bs = g_new0(struct simple_buddy, 1);
			bs->name = g_strdup(b->name);
			g_hash_table_insert(sip->buddies, bs->name, bs);
		}
		xmlnode_free(isc);
	}
	return 0;
}

static void simple_subscribe_buddylist(struct simple_account_data *sip) {
	gchar *contact = "Event: vnd-microsoft-roaming-contacts\r\nAccept: application/vnd-microsoft-roaming-contacts+xml\r\nSupported: com.microsoft.autoextend\r\nSupported: ms-benotify\r\nProxy-Require: ms-benotify\r\nSupported: ms-piggyback-first-notify\r\n";
	gchar *to;
	gchar *tmp;
	to = g_strdup_printf("sip:%s@%s", sip->username, sip->servername);

	tmp = get_contact(sip);

	contact = g_strdup_printf("%sContact: %s\r\n", contact, tmp);
	g_free(tmp);

	send_sip_request(sip->gc, "SUBSCRIBE", to, to, contact, "", NULL, simple_add_lcs_contacts);

	g_free(to);
	g_free(contact);
}


static void simple_buddy_resub(char *name, struct simple_buddy *buddy, struct simple_account_data *sip) {
	time_t curtime = time(NULL);
	purple_debug_info("simple", "buddy resub\n");
	if(buddy->resubscribe < curtime) {
		purple_debug(PURPLE_DEBUG_MISC, "simple", "simple_buddy_resub %s\n", name);
		simple_subscribe(sip, buddy);
	}
}

static gboolean resend_timeout(struct simple_account_data *sip) {
	GSList *tmp = sip->transactions;
	time_t currtime = time(NULL);
	while(tmp) {
		struct transaction *trans = tmp->data;
		tmp = tmp->next;
		purple_debug_info("simple", "have open transaction age: %d\n", currtime- trans->time);
		if((currtime - trans->time > 5) && trans->retries >= 1) {
			/* TODO 408 */
		} else {
			if((currtime - trans->time > 2) && trans->retries == 0) {
				trans->retries++;
				sendout_sipmsg(sip, trans->msg);
			}
		}
	}
	return TRUE;
}

static gboolean subscribe_timeout(struct simple_account_data *sip) {
	GSList *tmp;
	time_t curtime = time(NULL);
	/* register again if first registration expires */
	if(sip->reregister < curtime) {
		do_register(sip);
	}
	/* check for every subscription if we need to resubscribe */
	g_hash_table_foreach(sip->buddies, (GHFunc)simple_buddy_resub, (gpointer)sip);

	/* remove a timed out suscriber */

	tmp = sip->watcher;
	while(tmp) {
		struct simple_watcher *watcher = tmp->data;
		if(watcher->expire < curtime) {
			watcher_remove(sip, watcher->name);
			tmp = sip->watcher;
		}
		if(tmp) tmp = tmp->next;
	}

	return TRUE;
}

static void simple_send_message(struct simple_account_data *sip, const char *to, const char *msg, const char *type) {
	gchar *hdr;
	gchar *fullto;
	if(strncmp("sip:", to, 4)) {
		fullto = g_strdup_printf("sip:%s", to);
	} else {
		fullto = g_strdup(to);
	}
	if(type) {
		hdr = g_strdup_printf("Content-Type: %s\r\n", type);