/* tinyproxy - A fast light-weight HTTP proxy
*
* Copyright (C) 1998 Steven Young <sdyoung@miranda.org>
* Copyright (C) 1998-2002 Robert James Kaes <rjkaes@users.sourceforge.net>
* Copyright (C) 2000 Chris Lightfoot <chris@ex-parrot.com>
* Copyright (C) 2009-2010 Mukund Sivaraman <muks@banu.com>
* Copyright (C) 2009-2010 Michael Adam <obnox@samba.org>
*
* 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.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
/* The initialize routine. Basically sets up all the initial stuff (logfile,
* listening socket, config options, etc.) and then sits there and loops
* over the new connections until the daemon is closed. Also has additional
* functions to handle the "user friendly" aspects of a program (usage,
* stats, etc.) Like any good program, most of the work is actually done
* elsewhere.
*/
#include "main.h"
#include "anonymous.h"
#include "buffer.h"
#include "conf.h"
#include "daemon.h"
#include "heap.h"
#include "filter.h"
#include "child.h"
#include "log.h"
#include "reqs.h"
#include "sock.h"
#include "stats.h"
#include "utils.h"
/*
* Global Structures
*/
struct config_s *config;
static struct config_s config_main;
static struct config_s config_defaults;
static const char* config_file;
unsigned int received_sighup = FALSE; /* boolean */
/*
* Handle a signal
*/
static void
takesig (int sig)
{
pid_t pid;
int status;
switch (sig) {
case SIGHUP:
received_sighup = TRUE;
break;
case SIGINT:
case SIGTERM:
config->quit = TRUE;
break;
case SIGCHLD:
while ((pid = waitpid (-1, &status, WNOHANG)) > 0) ;
break;
}
return;
}
/*
* Display the version information for the user.
*/
static void
display_version (void)
{
printf ("%s %s\n", PACKAGE, VERSION);
}
/*
* Display usage to the user.
*/
static void
display_usage (void)
{
int features = 0;
printf ("Usage: %s [options]\n", PACKAGE);
printf ("\n"
"Options are:\n"
" -d Do not daemonize (run in foreground).\n"
" -c FILE Use an alternate configuration file.\n"
" -h Display this usage information.\n"
" -v Display version information.\n");
/* Display the modes compiled into tinyproxy */
printf ("\nFeatures compiled in:\n");
#ifdef XTINYPROXY_ENABLE
printf (" XTinyproxy header\n");
features++;
#endif /* XTINYPROXY */
#ifdef FILTER_ENABLE
printf (" Filtering\n");
features++;
#endif /* FILTER_ENABLE */
#ifndef NDEBUG
printf (" Debugging code\n");
features++;
#endif /* NDEBUG */
#ifdef TRANSPARENT_PROXY
printf (" Transparent proxy support\n");
features++;
#endif /* TRANSPARENT_PROXY */
#ifdef REVERSE_SUPPORT
printf (" Reverse proxy support\n");
features++;
#endif /* REVERSE_SUPPORT */
#ifdef UPSTREAM_SUPPORT
printf (" Upstream proxy support\n");
features++;
#endif /* UPSTREAM_SUPPORT */
if (0 == features)
printf (" None\n");
printf ("\n"
"For support and bug reporting instructions, please visit\n"
"<https://tinyproxy.github.io/>.\n");
}
static int
get_id (char *str)
{
char *tstr;
if (str == NULL)
return -1;
tstr = str;
while (*tstr != 0) {
if (!isdigit (*tstr))
return -1;
tstr++;
}
return atoi (str);
}
/**
* change_user:
* @program: The name of the program. Pass argv[0] here.
*
* This function tries to change UID and GID to the ones specified in
* the config file. This function is typically called during
* initialization when the effective user is root.
**/
static void
change_user (const char *program)
{
if (config->group && strlen (config->group) > 0) {
int gid = get_id (config->group);
if (gid < 0) {
struct group *thisgroup = getgrnam (config->group);
if (!thisgroup) {
fprintf (stderr,
"%s: Unable to find group \"%s\".\n",
program, config->group);
exit (EX_NOUSER);
}
gid = thisgroup->gr_gid;
}
if (setgid (gid) < 0) {
fprintf (stderr,
"%s: Unable to change to group \"%s\".\n",
program, config->group);
exit (EX_NOPERM);
}
#ifdef HAVE_SETGROUPS
/* Drop all supplementary groups, otherwise these are inherited from the calling process */
if (setgroups (0, NULL) < 0) {
fprintf (stderr,
"%s: Unable to drop supplementary groups.\n",
program);
exit (EX_NOPERM);
}
#endif
log_message (LOG_INFO, "Now running as group \"%s\".",
config->group);
}
if (config->user && strlen (config->user) > 0) {
int uid = get_id (config->user);
if (uid < 0) {
struct passwd *thisuser = getpwnam (config->user);
if (!thisuser) {
fprintf (stderr,
"%s: Unable to find user \"%s\".\n",
program, config->user);
exit (EX_NOUSER);
}
uid = thisuser->pw_uid;
}
if (setuid (uid) < 0) {
fprintf (stderr,
"%s: Unable to change to user \"%s\".\n",
program, config->user);
exit (EX_NOPERM);
}
log_message (LOG_INFO, "Now running as user \"%s\".",
config->user);
}
}
/**
* convenience wrapper around reload_config_file
* that also re-initializes logging.
*/
int reload_config (void)
{
int ret;
shutdown_logging ();
ret = reload_config_file (config_file, &config_main,
&config_defaults);
if (ret != 0) {
goto done;
}
config = &config_main;
ret = setup_logging ();
done:
return ret;
}
int
main (int argc, char **argv)
{
int opt, daemonized = TRUE;
srand(time(NULL)); /* for hashmap seeds */
/* Only allow u+rw bits. This may be required for some versions
* of glibc so that mkstemp() doesn't make us vulnerable.
*/
umask (0177);
log_message (LOG_INFO, "Initializing " PACKAGE " ...");
if (config_compile_regex()) {
exit (EX_SOFTWARE);
}
config_file = SYSCONFDIR "/tinyproxy.conf";
while ((opt = getopt (argc, argv, "c:vdh")) != EOF) {
switch (opt) {
case 'v':
display_version ();
exit (EX_OK);
case 'd':
daemonized = FALSE;
break;
case 'c':
config_file = optarg;
break;
case 'h':
display_usage ();
exit (EX_OK);
default:
display_usage ();
exit (EX_USAGE);
}
}
initialize_config_defaults (&config_defaults);
if (reload_config_file (config_file,
&config_main,
&config_defaults)) {
exit (EX_SOFTWARE);
}
config = &config_main;
init_stats ();
/* If ANONYMOUS is turned on, make sure that Content-Length is
* in the list of allowed headers, since it is required in a
* HTTP/1.0 request. Also add the Content-Type header since it
* goes hand in hand with Content-Length. */
if (is_anonymous_enabled ()) {
anonymous_insert ("Content-Length");
anonymous_insert ("Content-Type");
}
if (daemonized == TRUE) {
if (!config->syslog && config->logf_name == NULL)
fprintf(stderr, "WARNING: logging deactivated "
"(can't log to stdout when daemonized)\n");
makedaemon ();
}
if (set_signal_handler (SIGPIPE, SIG_IGN) == SIG_ERR) {
fprintf (stderr, "%s: Could not set the \"SIGPIPE\" signal.\n",
argv[0]);
exit (EX_OSERR);
}
#ifdef FILTER_ENABLE
if (config->filter)
filter_init ();
#endif /* FILTER_ENABLE */
/* Start listening on the selected port. */
if (child_listening_sockets(config->listen_addrs, config->port) < 0) {
fprintf (stderr, "%s: Could not create listening sockets.\n",
argv[0]);
exit (EX_OSERR);
}
/* Create pid file before we drop privileges */
if (config->pidpath) {
if (pidfile_create (config->pidpath) < 0) {
fprintf (stderr, "%s: Could not create PID file.\n",
argv[0]);
exit (EX_OSERR);
}
}
/* Switch to a different user if we're running as root */
if (geteuid () == 0)
change_user (argv[0]);
else
log_message (LOG_WARNING,
"Not running as root, so not changing UID/GID.");
/* Create log file after we drop privileges */
if (setup_logging ()) {
exit (EX_SOFTWARE);
}
/* These signals are only for the parent process. */
log_message (LOG_INFO, "Setting the various signals.");
if (set_signal_handler (SIGCHLD, takesig) == SIG_ERR) {
fprintf (stderr, "%s: Could not set the \"SIGCHLD\" signal.\n",
argv[0]);
exit (EX_OSERR);
}
if (set_signal_handler (SIGTERM, takesig) == SIG_ERR) {
fprintf (stderr, "%s: Could not set the \"SIGTERM\" signal.\n",
argv[0]);
exit (EX_OSERR);
}
if (set_signal_handler (SIGHUP, takesig) == SIG_ERR) {
fprintf (stderr, "%s: Could not set the \"SIGHUP\" signal.\n",
argv[0]);
exit (EX_OSERR);
}
/* Start the main loop */
log_message (LOG_INFO, "Starting main loop. Accepting connections.");
child_main_loop ();
log_message (LOG_INFO, "Shutting down.");
child_kill_children (SIGTERM);
child_close_sock ();
/* Remove the PID file */
if (config->pidpath != NULL && unlink (config->pidpath) < 0) {
log_message (LOG_WARNING,
"Could not remove PID file \"%s\": %s.",
config->pidpath, strerror (errno));
}
#ifdef FILTER_ENABLE
if (config->filter)
filter_destroy ();
#endif /* FILTER_ENABLE */
shutdown_logging ();
return EXIT_SUCCESS;
}