httpconn.c

Linux下的多协议即时通讯程序源代码

/**
 * @file httpmethod.c HTTP connection method
 *
 * purple
 *
 * Purple is the legal property of its developers, whose names are too numerous
 * to list here.  Please refer to the COPYRIGHT file distributed with this
 * source distribution.
 *
 * 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */
#include "msn.h"
#include "debug.h"
#include "httpconn.h"

typedef struct
{
	MsnHttpConn *httpconn;
	char *body;
	size_t body_len;
} MsnHttpQueueData;

static void
msn_httpconn_process_queue(MsnHttpConn *httpconn)
{
	httpconn->waiting_response = FALSE;

	if (httpconn->queue != NULL)
	{
		MsnHttpQueueData *queue_data;

		queue_data = (MsnHttpQueueData *)httpconn->queue->data;

		httpconn->queue = g_list_remove(httpconn->queue, queue_data);

		msn_httpconn_write(queue_data->httpconn,
						   queue_data->body,
						   queue_data->body_len);

		g_free(queue_data->body);
		g_free(queue_data);
	}
}

static gboolean
msn_httpconn_parse_data(MsnHttpConn *httpconn, const char *buf,
						size_t size, char **ret_buf, size_t *ret_size,
						gboolean *error)
{
	const char *s, *c;
	char *header, *body;
	const char *body_start;
	char *tmp;
	size_t body_len = 0;
	gboolean wasted = FALSE;

	g_return_val_if_fail(httpconn != NULL, FALSE);
	g_return_val_if_fail(buf      != NULL, FALSE);
	g_return_val_if_fail(size      > 0,    FALSE);
	g_return_val_if_fail(ret_buf  != NULL, FALSE);
	g_return_val_if_fail(ret_size != NULL, FALSE);
	g_return_val_if_fail(error    != NULL, FALSE);

#if 0
	purple_debug_info("msn", "HTTP: parsing data {%s}\n", buf);
#endif

	/* Healthy defaults. */
	body = NULL;

	*ret_buf  = NULL;
	*ret_size = 0;
	*error    = FALSE;

	/* First, some tests to see if we have a full block of stuff. */
	if (((strncmp(buf, "HTTP/1.1 200 OK\r\n", 17) != 0) &&
		 (strncmp(buf, "HTTP/1.1 100 Continue\r\n", 23) != 0)) &&
		((strncmp(buf, "HTTP/1.0 200 OK\r\n", 17) != 0) &&
		 (strncmp(buf, "HTTP/1.0 100 Continue\r\n", 23) != 0)))
	{
		*error = TRUE;

		return FALSE;
	}

	if (strncmp(buf, "HTTP/1.1 100 Continue\r\n", 23) == 0)
	{
		if ((s = strstr(buf, "\r\n\r\n")) == NULL)
			return FALSE;

		s += 4;

		if (*s == '\0')
		{
			*ret_buf = g_strdup("");
			*ret_size = 0;

			msn_httpconn_process_queue(httpconn);

			return TRUE;
		}

		buf = s;
		size -= (s - buf);
	}

	if ((s = strstr(buf, "\r\n\r\n")) == NULL)
		/* Need to wait for the full HTTP header to arrive */
		return FALSE;

	s += 4; /* Skip \r\n */
	header = g_strndup(buf, s - buf);
	body_start = s;
	body_len = size - (body_start - buf);

	if ((s = purple_strcasestr(header, "Content-Length: ")) != NULL)
	{
		int tmp_len;

		s += strlen("Content-Length: ");

		if ((c = strchr(s, '\r')) == NULL)
		{
			g_free(header);

			return FALSE;
		}

		tmp = g_strndup(s, c - s);
		tmp_len = atoi(tmp);
		g_free(tmp);

		if (body_len != tmp_len)
		{
			/* Need to wait for the full packet to arrive */

			g_free(header);

#if 0
			purple_debug_warning("msn",
							   "body length (%d) != content length (%d)\n",
							   body_len, tmp_len);
#endif

			return FALSE;
		}
	}

	body = g_malloc0(body_len + 1);
	memcpy(body, body_start, body_len);

#ifdef MSN_DEBUG_HTTP
	purple_debug_misc("msn", "Incoming HTTP buffer (header): {%s\r\n}\n",
					header);
#endif

	/* Now we should be able to process the data. */
	if ((s = purple_strcasestr(header, "X-MSN-Messenger: ")) != NULL)
	{
		char *full_session_id, *gw_ip, *session_action;
		char *t, *session_id;
		char **elems, **cur, **tokens;

		full_session_id = gw_ip = session_action = NULL;

		s += strlen("X-MSN-Messenger: ");

		if ((c = strchr(s, '\r')) == NULL)
		{
			msn_session_set_error(httpconn->session,
								  MSN_ERROR_HTTP_MALFORMED, NULL);
			purple_debug_error("msn", "Malformed X-MSN-Messenger field.\n{%s}",
							 buf);

			g_free(body);
			return FALSE;
		}

		tmp = g_strndup(s, c - s);

		elems = g_strsplit(tmp, "; ", 0);

		for (cur = elems; *cur != NULL; cur++)
		{
			tokens = g_strsplit(*cur, "=", 2);

			if (strcmp(tokens[0], "SessionID") == 0)
				full_session_id = tokens[1];
			else if (strcmp(tokens[0], "GW-IP") == 0)
				gw_ip = tokens[1];
			else if (strcmp(tokens[0], "Session") == 0)
				session_action = tokens[1];
			else
				g_free(tokens[1]);

			g_free(tokens[0]);
			/* Don't free each of the tokens, only the array. */
			g_free(tokens);
		}

		g_strfreev(elems);

		g_free(tmp);

		if ((session_action != NULL) && (strcmp(session_action, "close") == 0))
			wasted = TRUE;

		g_free(session_action);

		t = strchr(full_session_id, '.');
		session_id = g_strndup(full_session_id, t - full_session_id);

		if (!wasted)
		{
			g_free(httpconn->full_session_id);
			httpconn->full_session_id = full_session_id;

			g_free(httpconn->session_id);
			httpconn->session_id = session_id;

			g_free(httpconn->host);
			httpconn->host = gw_ip;
		}
		else
		{
			MsnServConn *servconn;

			/* It's going to die. */
			/* poor thing */

			servconn = httpconn->servconn;

			/* I'll be honest, I don't fully understand all this, but this
			 * causes crashes, Stu. */
			/* if (servconn != NULL)
				servconn->wasted = TRUE; */

			g_free(full_session_id);
			g_free(session_id);
			g_free(gw_ip);
		}
	}

	g_free(header);

	*ret_buf  = body;
	*ret_size = body_len;

	msn_httpconn_process_queue(httpconn);

	return TRUE;
}

static void
read_cb(gpointer data, gint source, PurpleInputCondition cond)
{
	MsnHttpConn *httpconn;
	MsnServConn *servconn;
	MsnSession *session;
	char buf[MSN_BUF_LEN];
	char *cur, *end, *old_rx_buf;
	int len, cur_len;
	char *result_msg = NULL;
	size_t result_len = 0;
	gboolean error = FALSE;

	httpconn = data;
	servconn = NULL;
	session = httpconn->session;

	len = read(httpconn->fd, buf, sizeof(buf) - 1);

	if (len < 0 && errno == EAGAIN)
		return;
	else if (len <= 0)
	{
		purple_debug_error("msn", "HTTP: Read error\n");
		msn_servconn_got_error(httpconn->servconn, MSN_SERVCONN_ERROR_READ);

		return;
	}

	buf[len] = '\0';

	httpconn->rx_buf = g_realloc(httpconn->rx_buf, len + httpconn->rx_len + 1);
	memcpy(httpconn->rx_buf + httpconn->rx_len, buf, len + 1);
	httpconn->rx_len += len;

	if (!msn_httpconn_parse_data(httpconn, httpconn->rx_buf, httpconn->rx_len,
								 &result_msg, &result_len, &error))
	{
		/* Either we must wait for more input, or something went wrong */
		if (error)
			msn_servconn_got_error(httpconn->servconn, MSN_SERVCONN_ERROR_READ);

		return;
	}

	httpconn->servconn->processing = FALSE;

	servconn = httpconn->servconn;

	if (error)
	{
		purple_debug_error("msn", "HTTP: Special error\n");
		msn_servconn_got_error(httpconn->servconn, MSN_SERVCONN_ERROR_READ);

		return;
	}

	g_free(httpconn->rx_buf);
	httpconn->rx_buf = NULL;
	httpconn->rx_len = 0;

	if (result_len == 0)
	{
		/* Nothing to do here */
#if 0
		purple_debug_info("msn", "HTTP: nothing to do here\n");
#endif
		g_free(result_msg);
		return;
	}

	g_free(servconn->rx_buf);
	servconn->rx_buf = result_msg;
	servconn->rx_len = result_len;

	end = old_rx_buf = servconn->rx_buf;

	servconn->processing = TRUE;

	do
	{
		cur = end;

		if (servconn->payload_len)
		{
			if (servconn->payload_len > servconn->rx_len)
				/* The payload is still not complete. */
				break;

			cur_len = servconn->payload_len;
			end += cur_len;
		}
		else
		{
			end = strstr(cur, "\r\n");

			if (end == NULL)
				/* The command is still not complete. */
				break;

			*end = '\0';
			end += 2;
			cur_len = end - cur;
		}

		servconn->rx_len -= cur_len;

		if (servconn->payload_len)
		{
			msn_cmdproc_process_payload(servconn->cmdproc, cur, cur_len);
			servconn->payload_len = 0;
		}
		else
		{
			msn_cmdproc_process_cmd_text(servconn->cmdproc, cur);
		}
	} while (servconn->connected && servconn->rx_len > 0);

	if (servconn->connected)
	{
		if (servconn->rx_len > 0)
			servconn->rx_buf = g_memdup(cur, servconn->rx_len);
		else