-/*
- * Guacamole - Clientless Remote Desktop
- * Copyright (C) 2010 Michael Jumper
+/* ***** BEGIN LICENSE BLOCK *****
+ * Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU Affero General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * (at your option) any later version.
+ * The contents of this file are subject to the Mozilla Public License Version
+ * 1.1 (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ * http://www.mozilla.org/MPL/
*
- * 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 Affero General Public License for more details.
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+ * for the specific language governing rights and limitations under the
+ * License.
*
- * You should have received a copy of the GNU Affero General Public License
- * along with this program. If not, see <http://www.gnu.org/licenses/>.
- */
+ * The Original Code is guacd.
+ *
+ * The Initial Developer of the Original Code is
+ * Michael Jumper.
+ * Portions created by the Initial Developer are Copyright (C) 2010
+ * the Initial Developer. All Rights Reserved.
+ *
+ * Contributor(s):
+ *
+ * Alternatively, the contents of this file may be used under the terms of
+ * either the GNU General Public License Version 2 or later (the "GPL"), or
+ * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
+ * in which case the provisions of the GPL or the LGPL are applicable instead
+ * of those above. If you wish to allow use of your version of this file only
+ * under the terms of either the GPL or the LGPL, and not to allow others to
+ * use your version of this file under the terms of the MPL, indicate your
+ * decision by deleting the provisions above and replace them with the notice
+ * and other provisions required by the GPL or the LGPL. If you do not delete
+ * the provisions above, a recipient may use your version of this file under
+ * the terms of any one of the MPL, the GPL or the LGPL.
+ *
+ * ***** END LICENSE BLOCK ***** */
#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
+#include <signal.h>
#include <sys/types.h>
+
#include <sys/socket.h>
+#include <netdb.h>
#include <netinet/in.h>
-#include <pthread.h>
#include <errno.h>
#include <syslog.h>
#include <guacamole/client.h>
+#include <guacamole/error.h>
-typedef struct client_thread_data {
+#include "client.h"
+#include "log.h"
- int fd;
+void guacd_handle_connection(int fd) {
-} client_thread_data;
+ guac_client* client;
+ guac_client_plugin* plugin;
+ guac_instruction* select;
+ guac_instruction* connect;
+ /* Open guac_socket */
+ guac_socket* socket = guac_socket_open(fd);
-void* start_client_thread(void* data) {
+ /* Get protocol from select instruction */
+ select = guac_protocol_expect_instruction(
+ socket, GUACD_USEC_TIMEOUT, "select");
+ if (select == NULL) {
- guac_client* client;
- client_thread_data* thread_data = (client_thread_data*) data;
+ /* Log error */
+ guacd_log_guac_error("Error reading \"select\"");
+
+ /* Free resources */
+ guac_socket_close(socket);
+ return;
+ }
+
+ /* Validate args to select */
+ if (select->argc != 1) {
+
+ /* Log error */
+ guacd_log_error("Bad number of arguments to \"select\" (%i)",
+ select->argc);
+
+ /* Free resources */
+ guac_socket_close(socket);
+ return;
+ }
+
+ guacd_log_info("Protocol \"%s\" selected", select->argv[0]);
+
+ /* Get plugin from protocol in select */
+ plugin = guac_client_plugin_open(select->argv[0]);
+ guac_instruction_free(select);
+
+ if (plugin == NULL) {
+
+ /* Log error */
+ guacd_log_guac_error("Error loading client plugin");
+
+ /* Free resources */
+ guac_socket_close(socket);
+ return;
+ }
- syslog(LOG_INFO, "Spawning client");
+ /* Send args response */
+ if (guac_protocol_send_args(socket, plugin->args)
+ || guac_socket_flush(socket)) {
- /* Load and start client */
- client = guac_get_client(thread_data->fd);
+ /* Log error */
+ guacd_log_guac_error("Error sending \"args\"");
+
+ if (guac_client_plugin_close(plugin))
+ guacd_log_guac_error("Error closing client plugin");
+
+ guac_socket_close(socket);
+ return;
+ }
+
+ /* Get args from connect instruction */
+ connect = guac_protocol_expect_instruction(
+ socket, GUACD_USEC_TIMEOUT, "connect");
+ if (connect == NULL) {
+
+ /* Log error */
+ guacd_log_guac_error("Error reading \"connect\"");
+
+ if (guac_client_plugin_close(plugin))
+ guacd_log_guac_error("Error closing client plugin");
+
+ guac_socket_close(socket);
+ return;
+ }
+
+ /* Load and init client */
+ client = guac_client_plugin_get_client(plugin, socket,
+ connect->argc, connect->argv,
+ guacd_client_log_info, guacd_client_log_error);
+
+ guac_instruction_free(connect);
if (client == NULL) {
- syslog(LOG_ERR, "Client retrieval failed");
- return NULL;
+
+ guacd_log_guac_error("Error instantiating client");
+
+ if (guac_client_plugin_close(plugin))
+ guacd_log_guac_error("Error closing client plugin");
+
+ guac_socket_close(socket);
+ return;
}
- guac_start_client(client);
+ /* Start client threads */
+ guacd_log_info("Starting client");
+ if (guacd_client_start(client))
+ guacd_log_error("Client finished abnormally");
+ else
+ guacd_log_info("Client finished normally");
- guac_free_client(client);
+ /* Clean up */
+ guac_client_free(client);
+ if (guac_client_plugin_close(plugin))
+ guacd_log_error("Error closing client plugin");
/* Close socket */
- if (close(thread_data->fd) < 0) {
- syslog(LOG_ERR, "Error closing connection: %s", strerror(errno));
- free(data);
- return NULL;
- }
+ guac_socket_close(socket);
- syslog(LOG_INFO, "Client finished");
- free(data);
- return NULL;
+ return;
}
/* Server */
int socket_fd;
- struct sockaddr_in server_addr;
+ struct addrinfo* addresses;
+ struct addrinfo* current_address;
+ char bound_address[1024];
+ char bound_port[64];
int opt_on = 1;
+ struct addrinfo hints = {
+ .ai_family = AF_UNSPEC,
+ .ai_socktype = SOCK_STREAM,
+ .ai_protocol = IPPROTO_TCP
+ };
+
/* Client */
struct sockaddr_in client_addr;
- unsigned int client_addr_len;
+ socklen_t client_addr_len;
int connected_socket_fd;
/* Arguments */
- int listen_port = 4822; /* Default port */
+ char* listen_address = NULL; /* Default address of INADDR_ANY */
+ char* listen_port = "4822"; /* Default port */
+ char* pidfile = NULL;
int opt;
+ /* General */
+ int retval;
+
/* Daemon Process */
pid_t daemon_pid;
/* Parse arguments */
- while ((opt = getopt(argc, argv, "l:")) != -1) {
+ while ((opt = getopt(argc, argv, "l:b:p:")) != -1) {
if (opt == 'l') {
- listen_port = atoi(optarg);
- if (listen_port <= 0) {
- fprintf(stderr, "Invalid port: %s\n", optarg);
- exit(EXIT_FAILURE);
- }
+ listen_port = strdup(optarg);
+ }
+ else if (opt == 'b') {
+ listen_address = strdup(optarg);
+ }
+ else if (opt == 'p') {
+ pidfile = strdup(optarg);
}
else {
- fprintf(stderr, "USAGE: %s [-l LISTENPORT]\n", argv[0]);
+
+ fprintf(stderr, "USAGE: %s"
+ " [-l LISTENPORT]"
+ " [-b LISTENADDRESS]"
+ " [-p PIDFILE]\n", argv[0]);
+
exit(EXIT_FAILURE);
}
}
- /* Get binding address */
- memset(&server_addr, 0, sizeof(server_addr)); /* Zero struct */
- server_addr.sin_family = AF_INET;
- server_addr.sin_addr.s_addr = INADDR_ANY;
- server_addr.sin_port = htons(listen_port);
+ /* Get addresses for binding */
+ if ((retval = getaddrinfo(listen_address, listen_port, &hints, &addresses))) {
+ guacd_log_error("Error parsing given address or port: %s",
+ gai_strerror(retval));
+ exit(EXIT_FAILURE);
+ }
/* Get socket */
socket_fd = socket(AF_INET, SOCK_STREAM, 0);
if (socket_fd < 0) {
- fprintf(stderr, "Error opening socket: %s\n", strerror(errno));
+ guacd_log_error("Error opening socket: %s", strerror(errno));
exit(EXIT_FAILURE);
}
- if (setsockopt(socket_fd, SOL_SOCKET, SO_REUSEADDR, &opt_on, sizeof(opt_on))) {
- fprintf(stderr, "Warning: Unable to set socket options for reuse: %s\n", strerror(errno));
+ /* Allow socket reuse */
+ if (setsockopt(socket_fd, SOL_SOCKET, SO_REUSEADDR, (void*) &opt_on, sizeof(opt_on))) {
+ guacd_log_info("Unable to set socket options for reuse: %s", strerror(errno));
+ }
+
+ /* Attempt binding of each address until success */
+ current_address = addresses;
+ while (current_address != NULL) {
+
+ int retval;
+
+ /* Resolve hostname */
+ if ((retval = getnameinfo(current_address->ai_addr,
+ current_address->ai_addrlen,
+ bound_address, sizeof(bound_address),
+ bound_port, sizeof(bound_port),
+ NI_NUMERICHOST | NI_NUMERICSERV)))
+ guacd_log_error("Unable to resolve host: %s",
+ gai_strerror(retval));
+
+ /* Attempt to bind socket to address */
+ if (bind(socket_fd,
+ current_address->ai_addr,
+ current_address->ai_addrlen) == 0) {
+
+ guacd_log_info("Successfully bound socket to "
+ "host %s, port %s", bound_address, bound_port);
+
+ /* Done if successful bind */
+ break;
+
+ }
+
+ /* Otherwise log information regarding bind failure */
+ else
+ guacd_log_info("Unable to bind socket to "
+ "host %s, port %s: %s",
+ bound_address, bound_port, strerror(errno));
+
+ current_address = current_address->ai_next;
+
}
- /* Bind socket to address */
- if (bind(socket_fd, (struct sockaddr*) &server_addr,
- sizeof(server_addr)) < 0) {
- fprintf(stderr, "Error binding socket: %s\n", strerror(errno));
+ /* If unable to bind to anything, fail */
+ if (current_address == NULL) {
+ guacd_log_error("Unable to bind socket to any addresses.");
exit(EXIT_FAILURE);
- }
+ }
/* Fork into background */
daemon_pid = fork();
/* If error, fail */
if (daemon_pid == -1) {
- fprintf(stderr, "Error forking daemon process: %s\n", strerror(errno));
+ guacd_log_error("Error forking daemon process: %s", strerror(errno));
exit(EXIT_FAILURE);
}
- /* If parent, exit */
+ /* If parent, write PID file and exit */
else if (daemon_pid != 0) {
+
+ if (pidfile != NULL) {
+
+ /* Attempt to open pidfile and write PID */
+ FILE* pidf = fopen(pidfile, "w");
+ if (pidf) {
+ fprintf(pidf, "%d\n", daemon_pid);
+ fclose(pidf);
+ }
+
+ /* Warn on failure */
+ else {
+ guacd_log_error("Could not write PID file: %s", strerror(errno));
+ exit(EXIT_FAILURE);
+ }
+
+ }
+
exit(EXIT_SUCCESS);
}
- /* Otherwise, this is the daemon */
- syslog(LOG_INFO, "Started, listening on port %i", listen_port);
+ /* Open log */
+ openlog(NULL, LOG_PID, LOG_DAEMON);
+
+ /* Ignore SIGPIPE */
+ if (signal(SIGPIPE, SIG_IGN) == SIG_ERR) {
+ guacd_log_info("Could not set handler for SIGPIPE to ignore. SIGPIPE may cause termination of the daemon.");
+ }
+
+ /* Ignore SIGCHLD (force automatic removal of children) */
+ if (signal(SIGCHLD, SIG_IGN) == SIG_ERR) {
+ guacd_log_info("Could not set handler for SIGCHLD to ignore. Child processes may pile up in the process table.");
+ }
+
+ /* Log listening status */
+ syslog(LOG_INFO,
+ "Listening on host %s, port %s", bound_address, bound_port);
+
+ /* Free addresses */
+ freeaddrinfo(addresses);
/* Daemon loop */
for (;;) {
- pthread_t thread;
- client_thread_data* data;
+ pid_t child_pid;
/* Listen for connections */
if (listen(socket_fd, 5) < 0) {
- syslog(LOG_ERR, "Could not listen on socket: %s", strerror(errno));
+ guacd_log_error("Could not listen on socket: %s", strerror(errno));
return 3;
}
client_addr_len = sizeof(client_addr);
connected_socket_fd = accept(socket_fd, (struct sockaddr*) &client_addr, &client_addr_len);
if (connected_socket_fd < 0) {
- syslog(LOG_ERR, "Could not accept client connection: %s", strerror(errno));
+ guacd_log_error("Could not accept client connection: %s", strerror(errno));
return 3;
}
- data = malloc(sizeof(client_thread_data));
- data->fd = connected_socket_fd;
+ /*
+ * Once connection is accepted, send child into background.
+ *
+ * Note that we prefer fork() over threads for connection-handling
+ * processes as they give each connection its own memory area, and
+ * isolate the main daemon and other connections from errors in any
+ * particular client plugin.
+ */
+
+ child_pid = fork();
+
+ /* If error, log */
+ if (child_pid == -1)
+ guacd_log_error("Error forking child process: %s", strerror(errno));
+
+ /* If child, start client, and exit when finished */
+ else if (child_pid == 0) {
+ guacd_handle_connection(connected_socket_fd);
+ close(connected_socket_fd);
+ return 0;
+ }
- if (pthread_create(&thread, NULL, start_client_thread, (void*) data)) {
- syslog(LOG_ERR, "Could not create client thread: %s", strerror(errno));
- return 3;
+ /* If parent, close reference to child's descriptor */
+ else if (close(connected_socket_fd) < 0) {
+ guacd_log_error("Error closing daemon reference to child descriptor: %s", strerror(errno));
}
}
/* Close socket */
if (close(socket_fd) < 0) {
- syslog(LOG_ERR, "Could not close socket: %s", strerror(errno));
+ guacd_log_error("Could not close socket: %s", strerror(errno));
return 3;
}
projects / guacd.git / blobdiff