glibc/nscd/nscd.c

435 lines
10 KiB
C

/* Copyright (c) 1998 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Thorsten Kukuk <kukuk@vt.uni-paderborn.de>, 1998.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.
The GNU C 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
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If not,
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
/* nscd - Name Service Cache Daemon. Caches passwd and group. */
#include <argp.h>
#include <errno.h>
#include <error.h>
#include <libintl.h>
#include <locale.h>
#include <pthread.h>
#include <pwd.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include <sys/socket.h>
#include <sys/un.h>
#include "dbg_log.h"
#include "nscd.h"
/* Get libc version number. */
#include <version.h>
#define PACKAGE _libc_intl_domainname
/* Structure used by main() thread to keep track of the number of
active threads. Used to limit how many threads it will create
and under a shutdown condition to wait till all in-progress
requests have finished before "turning off the lights". */
typedef struct
{
int num_active;
pthread_cond_t thread_exit_cv;
pthread_mutex_t mutex;
} thread_info_t;
thread_info_t thread_info;
int do_shutdown = 0;
int disabled_passwd = 0;
int disabled_group = 0;
int go_background = 1;
const char *conffile = _PATH_NSCDCONF;
static void termination_handler (int signum);
static int check_pid (const char *file);
static int write_pid (const char *file);
static void handle_requests (void);
/* Name and version of program. */
static void print_version (FILE *stream, struct argp_state *state);
void (*argp_program_version_hook) (FILE *, struct argp_state *) = print_version;
/* Definitions of arguments for argp functions. */
static const struct argp_option options[] =
{
{ "config-file", 'f', N_("NAME"), 0,
N_("Read configuration data from NAME") },
{ "debug", 'd', NULL, 0,
N_("Do not fork and display messages on the current tty") },
{ "shutdown", 'K', NULL, 0, N_("Shut the server down") },
{ "statistic", 'g', NULL, 0, N_("Print current configuration statistic") },
{ NULL, 0, NULL, 0, NULL }
};
/* Short description of program. */
static const char doc[] = N_("Name Switch Cache Daemon.");
/* Prototype for option handler. */
static error_t parse_opt __P ((int key, char *arg, struct argp_state *state));
/* Data structure to communicate with argp functions. */
static struct argp argp =
{
options, parse_opt, NULL, doc,
};
int
main (int argc, char **argv)
{
int remaining;
/* Set locale via LC_ALL. */
setlocale (LC_ALL, "");
/* Set the text message domain. */
textdomain (PACKAGE);
/* Parse and process arguments. */
argp_parse (&argp, argc, argv, 0, &remaining, NULL);
if (remaining != argc)
{
error (0, 0, gettext ("wrong number of arguments"));
argp_help (&argp, stdout, ARGP_HELP_SEE, program_invocation_short_name);
exit (EXIT_FAILURE);
}
signal (SIGINT, termination_handler);
signal (SIGQUIT, termination_handler);
signal (SIGTERM, termination_handler);
signal (SIGPIPE, SIG_IGN);
/* Check if we are already running. */
if (check_pid (_PATH_NSCDPID))
{
fputs (_("already running"), stderr);
exit (EXIT_FAILURE);
}
/* Behave like a daemon. */
if (go_background)
{
openlog ("nscd", LOG_CONS | LOG_ODELAY, LOG_DAEMON);
if (daemon (0, 0) < 0)
{
fprintf (stderr, _("connot auto-background: %s\n"),
strerror (errno));
exit (EXIT_FAILURE);
}
if (write_pid (_PATH_NSCDPID) < 0)
dbg_log ("%s: %s", _PATH_NSCDPID, strerror (errno));
/* Ignore job control signals */
signal (SIGTTOU, SIG_IGN);
signal (SIGTTIN, SIG_IGN);
signal (SIGTSTP, SIG_IGN);
}
/* Cleanup files created by a previous `bind' */
unlink (_PATH_NSCDSOCKET);
nscd_parse_file (conffile);
/* Create first sockets */
init_sockets ();
/* Init databases */
if ((cache_pwdinit () < 0) || (cache_grpinit () < 0))
{
fputs (_("Not enough memory\n"), stderr);
return 1;
}
/* Handle incoming requests */
handle_requests ();
return 0;
}
/* Handle program arguments. */
static error_t
parse_opt (int key, char *arg, struct argp_state *state)
{
switch (key)
{
case 'd':
debug_flag = 1;
go_background = 0;
break;
case 'f':
conffile = arg;
break;
case 'K':
if (getuid () != 0)
{
printf (_("Only root is allowed to use this option!\n\n"));
exit (EXIT_FAILURE);
}
{
int sock = __nscd_open_socket ();
request_header req;
ssize_t nbytes;
if (sock == -1)
exit (EXIT_FAILURE);
req.version = NSCD_VERSION;
req.type = SHUTDOWN;
req.key_len = 0;
nbytes = write (sock, &req, sizeof (request_header));
close (sock);
if (nbytes != req.key_len)
exit (EXIT_FAILURE);
else
exit (EXIT_SUCCESS);
}
case 'g':
print_stat ();
exit (EXIT_SUCCESS);
default:
return ARGP_ERR_UNKNOWN;
}
return 0;
}
/* Print the version information. */
static void
print_version (FILE *stream, struct argp_state *state)
{
fprintf (stream, "nscd (GNU %s) %s\n", PACKAGE, VERSION);
fprintf (stream, gettext ("\
Copyright (C) %s Free Software Foundation, Inc.\n\
This is free software; see the source for copying conditions. There is NO\n\
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n\
"), "1998");
fprintf (stream, gettext ("Written by %s.\n"), "Thorsten Kukuk");
}
/* Create a socket connected to a name. */
int
__nscd_open_socket (void)
{
struct sockaddr_un addr;
int sock;
sock = socket (PF_UNIX, SOCK_STREAM, 0);
if (sock < 0)
return -1;
addr.sun_family = AF_UNIX;
strcpy (addr.sun_path, _PATH_NSCDSOCKET);
if (connect (sock, (struct sockaddr *) &addr, sizeof (addr)) < 0)
{
close (sock);
return -1;
}
return sock;
}
/* Cleanup. */
static void
termination_handler (int signum)
{
close_sockets ();
/* Clean up the files created by `bind'. */
unlink (_PATH_NSCDSOCKET);
/* Clean up pid file. */
unlink (_PATH_NSCDPID);
exit (EXIT_SUCCESS);
}
/* Returns 1 if the process in pid file FILE is running, 0 if not. */
static int
check_pid (const char *file)
{
FILE *fp;
fp = fopen (file, "r");
if (fp)
{
pid_t pid;
fscanf (fp, "%d", &pid);
fclose (fp);
if (kill (pid, 0) == 0)
return 1;
}
return 0;
}
/* Write the current process id to the file FILE.
Returns 0 if successful, -1 if not. */
static int
write_pid (const char *file)
{
FILE *fp;
fp = fopen (file, "w");
if (fp == NULL)
return -1;
fprintf (fp, "%d\n", getpid ());
if (ferror (fp))
return -1;
fclose (fp);
return 0;
}
/* Type of the lookup function for netname2user. */
typedef int (*pwbyname_function) (const char *name, struct passwd *pw,
char *buffer, size_t buflen);
/* Hanlde incoming requests. */
static
void handle_requests (void)
{
request_header req;
int conn; /* Handle on which connection (client) the request came from. */
int done = 0;
char *key;
while (!done)
{
key = NULL;
get_request (&conn, &req, &key);
if (debug_flag)
dbg_log (_("handle_requests: request received (Version = %d)"),
req.version);
switch (req.type)
{
case GETPWBYNAME:
{
param_t *param = malloc (sizeof (param_t));
pthread_t thread;
if (debug_flag)
dbg_log ("\tGETPWBYNAME (%s)", key);
param->key = key;
param->conn = conn;
if (disabled_passwd)
pthread_create (&thread, NULL, cache_pw_disabled, (void *)param);
else
pthread_create (&thread, NULL, cache_getpwnam, (void *)param);
pthread_detach (thread);
}
break;
case GETPWBYUID:
{
param_t *param = malloc (sizeof (param_t));
pthread_t thread;
if (debug_flag)
dbg_log ("\tGETPWBYUID (%s)", key);
param->key = key;
param->conn = conn;
if (disabled_passwd)
pthread_create (&thread, NULL, cache_pw_disabled, (void *)param);
else
pthread_create (&thread, NULL, cache_getpwuid, (void *)param);
pthread_detach (thread);
}
break;
case GETGRBYNAME:
{
param_t *param = malloc (sizeof (param_t));
pthread_t thread;
if (debug_flag)
dbg_log ("\tGETGRBYNAME (%s)", key);
param->key = key;
param->conn = conn;
if (disabled_group)
pthread_create (&thread, NULL, cache_gr_disabled, (void *)param);
else
pthread_create (&thread, NULL, cache_getgrnam, (void *)param);
pthread_detach (thread);
}
break;
case GETGRBYGID:
{
param_t *param = malloc (sizeof (param_t));
pthread_t thread;
if (debug_flag)
dbg_log ("\tGETGRBYGID (%s)", key);
param->key = key;
param->conn = conn;
if (disabled_group)
pthread_create (&thread, NULL, cache_gr_disabled, (void *)param);
else
pthread_create (&thread, NULL, cache_getgrgid, (void *)param);
pthread_detach (thread);
}
break;
case GETHOSTBYNAME:
/* Not yetimplemented. */
close_socket (conn);
break;
case GETHOSTBYADDR:
/* Not yet implemented. */
close_socket (conn);
break;
case SHUTDOWN:
do_shutdown = 1;
close_socket (0);
close_socket (conn);
/* Clean up the files created by `bind'. */
unlink (_PATH_NSCDSOCKET);
/* Clean up pid file. */
unlink (_PATH_NSCDPID);
done = 1;
break;
case GETSTAT:
{
stat_response_header resp;
if (debug_flag)
dbg_log ("\tGETSTAT");
get_pw_stat (&resp);
get_gr_stat (&resp);
resp.debug_level = debug_flag;
resp.pw_enabled = !disabled_passwd;
resp.gr_enabled = !disabled_group;
stat_send (conn, &resp);
close_socket (conn);
}
break;
default:
dbg_log (_("Unknown request (%d)"), req.type);
break;
}
}
}