Forked gnome-user-share. Work in progress.

1 files changed, 481 insertions, 0 deletions

diff --git a/src/http.c b/src/http.c
new file mode 100644
index 0000000..64d4706
--- /dev/null
+++ b/src/http.c
@@ -0,0 +1,481 @@
+/* -*- Mode: C; indent-tabs-mode: t; c-basic-offset: 4; tab-width: 4 -*- */
+
+/*
+ *  Copyright (C) 2004-2008 Red Hat, Inc.
+ *
+ *  Caja 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.
+ *
+ *  Caja 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., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ *  Authors: Alexander Larsson <[email protected]>
+ *
+ */
+
+#include "config.h"
+
+#include <glib.h>
+#include <glib/gi18n.h>
+#include <X11/Xlib.h>
+
+#ifdef HAVE_DBUS_1_1
+#include <dbus/dbus.h>
+#endif
+
+#include <mateconf/mateconf-client.h>
+
+#include <stdarg.h>
+#include <string.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <signal.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <sys/stat.h>
+
+#ifdef HAVE_SELINUX
+#include <selinux/selinux.h>
+#endif
+
+#include "user_share-common.h"
+#include "user_share-private.h"
+#include "http.h"
+
+/* From avahi-common/domain.h */
+#define AVAHI_LABEL_MAX 64
+
+#ifdef HAVE_DBUS_1_1
+static char *dbus_session_id;
+#endif
+
+static pid_t httpd_pid = 0;
+
+static int
+get_port (void)
+{
+	int sock;
+	struct sockaddr_in addr;
+	int reuse;
+	socklen_t len;
+
+	sock = socket (PF_INET, SOCK_STREAM, 0);
+	if (sock < 0) {
+		return -1;
+	}
+
+	memset (&addr, 0, sizeof (addr));
+	addr.sin_port = 0;
+	addr.sin_addr.s_addr = INADDR_ANY;
+
+	reuse = 1;
+	setsockopt (sock, SOL_SOCKET, SO_REUSEADDR, &reuse, sizeof (reuse));
+	if (bind (sock, (struct sockaddr *)&addr, sizeof (addr)) == -1) {
+		close (sock);
+		return -1;
+	}
+
+	len = sizeof (addr);
+	if (getsockname (sock, (struct sockaddr *)&addr, &len) == -1) {
+		close (sock);
+		return -1;
+	}
+
+#if defined(__FreeBSD__) || defined(__NetBSD__) || defined(__APPLE__)
+	/* XXX This exposes a potential race condition, but without this,
+	 * httpd will not start on the above listed platforms due to the fact
+	 * that SO_REUSEADDR is also needed when Apache binds to the listening
+	 * socket.  At this time, Apache does not support that socket option.
+	 */
+	close (sock);
+#endif
+	return ntohs (addr.sin_port);
+}
+
+static char *
+truncate_name (const char *name)
+{
+	const char *end;
+
+	end = g_utf8_find_prev_char (name, name + 64);
+	g_assert (end != NULL);
+	return g_strndup (name, end - name);
+}
+
+static char *
+get_share_name (void)
+{
+	static char *name = NULL;
+	const char *host_name;
+	char *str;
+
+	if (name == NULL) {
+		host_name = g_get_host_name ();
+		if (strcmp (host_name, "localhost") == 0) {
+			/* Translators: The %s will get filled in with the user name
+			   of the user, to form a genitive. If this is difficult to
+			   translate correctly so that it will work correctly in your
+			   language, you may use something equivalent to
+			   "Public files of %s", or leave out the %s altogether.
+			   In the latter case, please put "%.0s" somewhere in the string,
+			   which will match the user name string passed by the C code,
+			   but not put the user name in the final string. This is to
+			   avoid the warning that msgfmt might otherwise generate. */
+			name = g_strdup_printf (_("%s's public files"), g_get_user_name ());
+		} else {
+			/* Translators: This is similar to the string before, only it
+			   has the hostname in it too. */
+			name = g_strdup_printf (_("%s's public files on %s"),
+						g_get_user_name (),
+						host_name);
+		}
+
+	}
+	/* And truncate */
+	if (strlen (name) < AVAHI_LABEL_MAX)
+		return name;
+
+	str = truncate_name (name);
+	g_free (name);
+	name = str;
+
+	return name;
+}
+
+#ifdef HAVE_DBUS_1_1
+static void
+init_dbus() {
+	/* The only use we make of D-BUS is to fetch the session BUS ID so we can export
+	 * it via mDNS, so we connect and then immediately disconnect. If we were using
+	 * the D-BUS session BUS for something persistent, the following code should use
+	 * dbus_bus_get() and skip the shutdown. (Avahi uses the D-BUS  _system_ bus
+	 * internally.)
+	 */
+
+	DBusError derror;
+	DBusConnection *connection;
+
+	dbus_error_init(&derror);
+
+	connection = dbus_bus_get_private(DBUS_BUS_SESSION, &derror);
+	if (connection == NULL) {
+		g_printerr("Failed to connect to session bus: %s", derror.message);
+		dbus_error_free(&derror);
+		return;
+	}
+
+	dbus_session_id = dbus_bus_get_id(connection, &derror);
+	if (dbus_session_id == NULL) {
+		/* This can happen if the D-BUS library has been upgraded to 1.1, but the
+		 * user's session hasn't yet been restarted
+		 */
+		g_printerr("Failed to get session BUS ID: %s", derror.message);
+		dbus_error_free(&derror);
+	}
+
+	dbus_connection_set_exit_on_disconnect(connection, FALSE);
+	dbus_connection_close(connection);
+	dbus_connection_unref(connection);
+}
+#endif
+
+static void
+ensure_conf_dir (void)
+{
+	char *dirname;
+
+	dirname = g_build_filename (g_get_user_config_dir (), "user-share", NULL);
+	g_mkdir_with_parents (dirname, 0755);
+	g_free (dirname);
+}
+
+static void
+httpd_child_setup (gpointer user_data)
+{
+#ifdef HAVE_SELINUX
+	char *mycon;
+	/* If selinux is enabled, avoid transitioning to the httpd_t context,
+	   as this normally means you can't read the users homedir. */
+	if (is_selinux_enabled()) {
+		if (getcon (&mycon) < 0) {
+			abort ();
+		}
+		if (setexeccon (mycon) < 0)
+			abort ();
+		freecon (mycon);
+	}
+#endif
+}
+
+static const char *known_httpd_locations [] = {
+	HTTPD_PROGRAM,
+	"/usr/sbin/httpd",
+	"/usr/sbin/httpd2",
+	"/usr/sbin/apache2",
+	NULL
+};
+
+static char*
+get_httpd_program ()
+{
+	int i;
+
+	for (i = 0; known_httpd_locations[i]; i++) {
+		if (known_httpd_locations[i][0] == '\0') {
+			/* empty string as first element, happens when
+			 * configured --with-httpd=auto */
+			continue;
+		}
+		if (g_file_test (known_httpd_locations[i], G_FILE_TEST_IS_EXECUTABLE)
+				&& ! g_file_test (known_httpd_locations[i], G_FILE_TEST_IS_DIR)) {
+			return g_strdup (known_httpd_locations[i]);
+		}
+	}
+	return NULL;
+}
+
+static const char *known_httpd_modules_locations [] = {
+	HTTPD_MODULES_PATH,
+	"/etc/httpd/modules",
+	"/usr/lib/apache2/modules",
+	NULL
+};
+
+static gchar*
+get_httpd_modules_path ()
+{
+	int i;
+
+	for (i = 0; known_httpd_modules_locations[i]; i++) {
+		if (known_httpd_modules_locations[i][0] == '\0') {
+			/* empty string as first element, happens when
+			 * configured --with-httpd=auto */
+			continue;
+		}
+		if (g_file_test (known_httpd_modules_locations[i], G_FILE_TEST_IS_EXECUTABLE)
+				&& g_file_test (known_httpd_modules_locations[i], G_FILE_TEST_IS_DIR)) {
+			return g_strdup (known_httpd_modules_locations[i]);
+		}
+	}
+	return NULL;
+}
+
+static GRegex *version_regex = NULL;
+
+static char*
+get_httpd_config (const char *httpd_program)
+{
+	gchar *standard_output;
+	gchar *cmd_line;
+	GMatchInfo *match_info;
+	gchar *version_number = NULL;
+	gchar *config;
+
+	cmd_line = g_strdup_printf ("%s -v", httpd_program);
+	if (! g_spawn_command_line_sync (cmd_line, &standard_output, NULL, NULL, NULL)) {
+		g_free (cmd_line);
+		return NULL;
+	}
+	g_free (cmd_line);
+
+	if (version_regex == NULL) {
+		version_regex = g_regex_new ("\\d\\.\\d", 0, 0, NULL);
+	}
+
+	if (g_regex_match (version_regex, standard_output, 0, &match_info)) {
+		while (g_match_info_matches (match_info)) {
+			version_number = g_match_info_fetch (match_info, 0);
+			break;
+		}
+		g_match_info_free (match_info);
+		g_free (standard_output);
+	} else {
+		/* Failed to parse httpd version number */
+		g_warning ("Could not parse '%s' as a version for httpd", standard_output);
+		g_free (standard_output);
+		/* assume it is 2.2 */
+		version_number = g_strdup ("2.2");
+	}
+
+	config = g_strdup_printf (HTTPD_CONFIG_TEMPLATE, version_number);
+	g_free (version_number);
+
+	return config;
+}
+
+static gboolean
+spawn_httpd (int port, pid_t *pid_out)
+{
+	char *free1, *free2, *free3, *free4, *free5, *free6, *free7, *free8, *free9;
+	gboolean res;
+	char *argv[10];
+	char *env[10];
+	int i;
+	gint status;
+	char *pid_filename;
+	char *pidfile;
+	GError *error;
+	gboolean got_pidfile;
+	MateConfClient *client;
+	char *str;
+	char *public_dir;
+
+	public_dir = lookup_public_dir ();
+	ensure_conf_dir ();
+
+	i = 0;
+	free1 = argv[i++] = get_httpd_program ();
+	if (argv[0] == NULL) {
+		fprintf (stderr, "error finding httpd server\n");
+		return FALSE;
+	}
+
+	argv[i++] = "-f";
+	free2 = argv[i++] = get_httpd_config (argv[0]);
+	argv[i++] = "-C";
+	free3 = argv[i++] = g_strdup_printf ("Listen %d", port);
+
+	client = mateconf_client_get_default ();
+	str = mateconf_client_get_string (client,
+				       FILE_SHARING_REQUIRE_PASSWORD, NULL);
+
+	if (str && strcmp (str, "never") == 0) {
+		/* Do nothing */
+	} else if (str && strcmp (str, "on_write") == 0){
+		argv[i++] = "-D";
+		argv[i++] = "RequirePasswordOnWrite";
+	} else {
+		/* always, or safe fallback */
+		argv[i++] = "-D";
+		argv[i++] = "RequirePasswordAlways";
+	}
+	g_free (str);
+	g_object_unref (client);
+
+	argv[i] = NULL;
+
+	i = 0;
+	free4 = env[i++] = g_strdup_printf ("HOME=%s", g_get_home_dir());
+	free5 = env[i++] = g_strdup_printf ("XDG_PUBLICSHARE_DIR=%s", public_dir);
+	free6 = env[i++] = g_strdup_printf ("XDG_CONFIG_HOME=%s", g_get_user_config_dir ());
+	free7 = env[i++] = g_strdup_printf ("GUS_SHARE_NAME=%s", get_share_name ());
+	free8 = env[i++] = g_strdup_printf ("GUS_LOGIN_LABEL=%s", "Please log in as the user guest");
+	free9 = env[i++] = g_strdup_printf ("HTTP_MODULES_PATH=%s",get_httpd_modules_path ());
+	env[i++] = "LANG=C";
+	env[i] = NULL;
+
+	pid_filename = g_build_filename (g_get_user_config_dir (), "user-share", "pid", NULL);
+
+	/* Remove pid file before spawning to avoid races with child and old pidfile */
+	unlink (pid_filename);
+
+	error = NULL;
+	res = g_spawn_sync (g_get_home_dir(),
+			    argv, env, 0,
+			    httpd_child_setup, NULL,
+			    NULL, NULL,
+			    &status,
+			    &error);
+	g_free (free1);
+	g_free (free2);
+	g_free (free3);
+	g_free (free4);
+	g_free (free5);
+	g_free (free6);
+	g_free (free7);
+	g_free (free8);
+	g_free (free9);
+	g_free (public_dir);
+
+	if (!res) {
+		fprintf (stderr, "error spawning httpd: %s\n",
+			 error->message);
+		g_error_free (error);
+		return FALSE;
+	}
+
+	if (status != 0) {
+		g_free (pid_filename);
+		return FALSE;
+	}
+
+	got_pidfile = FALSE;
+	error = NULL;
+	for (i = 0; i < 5; i++) {
+		if (error != NULL) 
+			g_error_free (error); 
+		error = NULL;
+		if (g_file_get_contents (pid_filename, &pidfile, NULL, &error)) {
+			got_pidfile = TRUE;
+			*pid_out = atoi (pidfile);
+			g_free (pidfile);
+			break;
+		}
+		sleep (1);
+	}
+
+	g_free (pid_filename);
+
+	if (!got_pidfile) {
+		fprintf (stderr, "error opening httpd pidfile: %s\n", error->message);
+		g_error_free (error);
+		return FALSE;
+	}
+	return TRUE;
+}
+
+static void
+kill_httpd (void)
+{
+	if (httpd_pid != 0) {
+		kill (httpd_pid, SIGTERM);
+
+		/* Allow child time to die, we can't waitpid, because its
+		   not a direct child */
+		sleep (1);
+	}
+	httpd_pid = 0;
+}
+
+void
+http_up (void)
+{
+	guint port;
+
+	port = get_port ();
+	if (!spawn_httpd (port, &httpd_pid)) {
+		fprintf (stderr, "spawning httpd failed\n");
+	}
+}
+
+void
+http_down (void)
+{
+	kill_httpd ();
+}
+
+gboolean
+http_init (void)
+{
+#ifdef HAVE_DBUS_1_1
+	init_dbus();
+#endif	
+
+	return TRUE;
+}
+
+pid_t
+http_get_pid (void)
+{
+	return httpd_pid;
+}