odc.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
*/

/* From the oscar PRPL */
#include "oscar.h"
#include "peer.h"

/* From Purple */
#include "conversation.h"
#include "imgstore.h"
#include "util.h"

/**
 * Free any ODC related data and print a message to the conversation
 * window based on conn->disconnect_reason.
 */
void
peer_odc_close(PeerConnection *conn)
{
	gchar *tmp;

	if (conn->disconnect_reason == OSCAR_DISCONNECT_REMOTE_CLOSED)
		tmp = g_strdup(_("The remote user has closed the connection."));
	else if (conn->disconnect_reason == OSCAR_DISCONNECT_REMOTE_REFUSED)
		tmp = g_strdup(_("The remote user has declined your request."));
	else if (conn->disconnect_reason == OSCAR_DISCONNECT_LOST_CONNECTION)
		tmp = g_strdup_printf(_("Lost connection with the remote user:<br>%s"),
				conn->error_message);
	else if (conn->disconnect_reason == OSCAR_DISCONNECT_INVALID_DATA)
		tmp = g_strdup(_("Received invalid data on connection with remote user."));
	else if (conn->disconnect_reason == OSCAR_DISCONNECT_COULD_NOT_CONNECT)
		tmp = g_strdup(_("Could not establish a connection with the remote user."));
	else
		/*
		 * We shouldn't print a message for some disconnect_reasons.
		 * Like OSCAR_DISCONNECT_LOCAL_CLOSED.
		 */
		tmp = NULL;

	if (tmp != NULL)
	{
		PurpleAccount *account;
		PurpleConversation *conv;

		account = purple_connection_get_account(conn->od->gc);
		conv = purple_conversation_new(PURPLE_CONV_TYPE_IM, account, conn->sn);
		purple_conversation_write(conv, NULL, tmp, PURPLE_MESSAGE_SYSTEM, time(NULL));
		g_free(tmp);
	}

	if (conn->frame != NULL)
	{
		OdcFrame *frame;
		frame = conn->frame;
		g_free(frame->payload.data);
		g_free(frame);
	}
}

/**
 * Write the given OdcFrame to a ByteStream and send it out
 * on the established PeerConnection.
 */
static void
peer_odc_send(PeerConnection *conn, OdcFrame *frame)
{
	PurpleAccount *account;
	const char *username;
	size_t length;
	ByteStream bs;

	purple_debug_info("oscar", "Outgoing ODC frame to %s with "
		"type=0x%04x, flags=0x%04x, payload length=%u\n",
		conn->sn, frame->type, frame->flags, frame->payload.len);

	account = purple_connection_get_account(conn->od->gc);
	username = purple_account_get_username(account);
	memcpy(frame->sn, username, strlen(username));
	memcpy(frame->cookie, conn->cookie, 8);

	length = 76;
	byte_stream_new(&bs, length + frame->payload.len);
	byte_stream_putraw(&bs, conn->magic, 4);
	byte_stream_put16(&bs, length);
	byte_stream_put16(&bs, frame->type);
	byte_stream_put16(&bs, frame->subtype);
	byte_stream_put16(&bs, 0x0000);
	byte_stream_putraw(&bs, frame->cookie, 8);
	byte_stream_put16(&bs, 0x0000);
	byte_stream_put16(&bs, 0x0000);
	byte_stream_put16(&bs, 0x0000);
	byte_stream_put16(&bs, 0x0000);
	byte_stream_put32(&bs, frame->payload.len);
	byte_stream_put16(&bs, 0x0000);
	byte_stream_put16(&bs, frame->encoding);
	byte_stream_put16(&bs, 0x0000);
	byte_stream_put16(&bs, frame->flags);
	byte_stream_put16(&bs, 0x0000);
	byte_stream_put16(&bs, 0x0000);
	byte_stream_putraw(&bs, frame->sn, 32);
	byte_stream_putraw(&bs, frame->payload.data, frame->payload.len);

	peer_connection_send(conn, &bs);

	g_free(bs.data);
}

/**
 * Send a very basic ODC frame (which contains the cookie) so that the
 * remote user can verify that we are the person they were expecting.
 * If we made an outgoing connection to then remote user, then we send
 * this immediately.  If the remote user connected to us, then we wait
 * for the other person to send this to us, then we send one to them.
 */
void
peer_odc_send_cookie(PeerConnection *conn)
{
	OdcFrame frame;

	memset(&frame, 0, sizeof(OdcFrame));
	frame.type = 0x0001;
	frame.subtype = 0x0006;
	frame.flags = 0x0060; /* Maybe this means "we're sending the cookie"? */

	peer_odc_send(conn, &frame);
}

/**
 * Send client-to-client typing notification over an established direct connection.
 */
void
peer_odc_send_typing(PeerConnection *conn, PurpleTypingState typing)
{
	OdcFrame frame;

	memset(&frame, 0, sizeof(OdcFrame));
	frame.type = 0x0001;
	frame.subtype = 0x0006;
	if (typing == PURPLE_TYPING)
		frame.flags = 0x0002 | 0x0008;
	else if (typing == PURPLE_TYPED)
		frame.flags = 0x0002 | 0x0004;
	else
		frame.flags = 0x0002;

	peer_odc_send(conn, &frame);
}

/**
 * Send client-to-client IM over an established direct connection.
 * To send a direct IM, call this just like you would aim_send_im.
 *
 * @param conn The already-connected ODC connection.
 * @param msg Null-terminated string to send.
 * @param len The length of the message to send, including binary data.
 * @param encoding See the AIM_CHARSET_* defines in oscar.h
 * @param autoreply TRUE if this is any auto-reply.
 */
void
peer_odc_send_im(PeerConnection *conn, const char *msg, int len, int encoding, gboolean autoreply)
{
	OdcFrame frame;

	g_return_if_fail(msg != NULL);
	g_return_if_fail(len > 0);

	memset(&frame, 0, sizeof(OdcFrame));
	frame.type = 0x0001;
	frame.subtype = 0x0006;
	frame.payload.len = len;
	frame.encoding = encoding;
	frame.flags = autoreply;
	byte_stream_new(&frame.payload, len);
	byte_stream_putraw(&frame.payload, (guint8 *)msg, len);

	peer_odc_send(conn, &frame);

	g_free(frame.payload.data);
}

struct embedded_data
{
	size_t size;
	const guint8 *data;
};

/**
 * This is called after a direct IM has been received in its entirety.  This
 * function is passed a long chunk of data which contains the IM with any
 * data chunks (images) appended to it.
 *
 * This function rips out all the data chunks and creates an imgstore for
 * each one.  In order to do this, it first goes through the IM and takes
 * out all the IMG tags.  When doing so, it rewrites the original IMG tag
 * with one compatible with the imgstore Purple core code. For each one, we
 * then read in chunks of data from the end of the message and actually
 * create the img store using the given data.
 *
 * For somewhat easy reference, here's a sample message
 * (with added whitespace):
 *
 * <HTML><BODY BGCOLOR="#ffffff">
 *     <FONT LANG="0">
 *     This is a really stupid picture:<BR>
 *     <IMG SRC="Sample.jpg" ID="1" WIDTH="283" HEIGHT="212" DATASIZE="9894"><BR>
 *     Yeah it is<BR>
 *     Here is another one:<BR>
 *     <IMG SRC="Soap Bubbles.bmp" ID="2" WIDTH="256" HEIGHT="256" DATASIZE="65978">
 *     </FONT>
 * </BODY></HTML>
 * <BINARY>
 *     <DATA ID="1" SIZE="9894">datadatadatadata</DATA>
 *     <DATA ID="2" SIZE="65978">datadatadatadata</DATA>
 * </BINARY>
 */
static void
peer_odc_handle_payload(PeerConnection *conn, const char *msg, size_t len, int encoding, gboolean autoreply)
{
	PurpleConnection *gc;
	PurpleAccount *account;
	const char *msgend, *binary_start, *dataend;
	const char *tmp, *start, *end, *idstr, *src, *sizestr;
	GData *attributes;
	GHashTable *embedded_datas;
	struct embedded_data *embedded_data;
	GSList *images;
	gchar *utf8;
	GString *newmsg;
	PurpleMessageFlags imflags;

	gc = conn->od->gc;
	account = purple_connection_get_account(gc);

	dataend = msg + len;

	/*
	 * Create a hash table containing references to each embedded
	 * data chunk.  The key is the "ID" and the value is an
	 * embedded_data struct.
	 */
	embedded_datas = g_hash_table_new_full(g_direct_hash,
			g_direct_equal, NULL, g_free);

	/*
	 * Create an index of any binary chunks.  If we run into any
	 * problems while parsing the binary data section then we stop
	 * parsing it, and the local user will see broken image icons.
	 */
	/* TODO: Use a length argument when looking for the <binary> tag! */
	binary_start = purple_strcasestr(msg, "<binary>");
	if (binary_start == NULL)
		msgend = dataend;
	else
	{
		msgend = binary_start;

		/* Move our pointer to immediately after the <binary> tag */
		tmp = binary_start + 8;

		/* The embedded binary markup has a mimimum length of 29 bytes */
		/* TODO: Use a length argument when looking for the <data> tag! */
		while ((tmp + 29 <= dataend) &&
				purple_markup_find_tag("data", tmp, &start, &tmp, &attributes))
		{
			unsigned int id;
			size_t size;

			/* Move the binary pointer from ">" to the start of the data */
			tmp++;

			/* Get the ID */
			idstr = g_datalist_get_data(&attributes, "id");
			if (idstr == NULL)
			{
				g_datalist_clear(&attributes);
				break;
			}
			id = atoi(idstr);

			/* Get the size */
			sizestr = g_datalist_get_data(&attributes, "size");
			if (sizestr == NULL)
			{
				g_datalist_clear(&attributes);