/* Copyright (C) 2000, 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
This file is part of GNU Inetutils.
GNU Inetutils 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, or (at your option)
any later version.
GNU Inetutils is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR 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 GNU Inetutils; see the file COPYING. If not, write to
the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
/*
* Copyright (c) 1983, 1991, 1993, 1994
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#if 0
static char sccsid[] = "@(#)inetd.c 8.4 (Berkeley) 4/13/94";
#endif
/*
* Inetd - Internet super-server
*
* This program invokes all internet services as needed. Connection-oriented
* services are invoked each time a connection is made, by creating a process.
* This process is passed the connection as file descriptor 0 and is expected
* to do a getpeername to find out the source host and port.
*
* Datagram oriented services are invoked when a datagram
* arrives; a process is created and passed a pending message
* on file descriptor 0. Datagram servers may either connect
* to their peer, freeing up the original socket for inetd
* to receive further messages on, or ``take over the socket'',
* processing all arriving datagrams and, eventually, timing
* out. The first type of server is said to be ``multi-threaded'';
* the second type of server ``single-threaded''.
*
* Inetd uses a configuration file which is read at startup
* and, possibly, at some later time in response to a hangup signal.
* The configuration file is ``free format'' with fields given in the
* order shown below. Continuation lines for an entry must being with
* a space or tab. All fields must be present in each entry.
*
* service name must be in /etc/services or must
* name a tcpmux service
* socket type stream/dgram/raw/rdm/seqpacket
* protocol must be in /etc/protocols
* wait/nowait single-threaded/multi-threaded
* user user to run daemon as
* server program full path name
* server program arguments arguments starting with argv[0]
*
* TCP services without official port numbers are handled with the
* RFC1078-based tcpmux internal service. Tcpmux listens on port 1 for
* requests. When a connection is made from a foreign host, the service
* requested is passed to tcpmux, which looks it up in the servtab list
* and returns the proper entry for the service. Tcpmux returns a
* negative reply if the service doesn't exist, otherwise the invoked
* server is expected to return the positive reply if the service type in
* inetd.conf file has the prefix "tcpmux/". If the service type has the
* prefix "tcpmux/+", tcpmux will return the positive reply for the
* process; this is for compatibility with older server code, and also
* allows you to invoke programs that use stdin/stdout without putting any
* special server code in them. Services that use tcpmux are "nowait"
* because they do not have a well-known port and hence cannot listen
* for new requests.
*
* Comment lines are indicated by a `#' in column 1.
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <sys/types.h>
#include <sys/param.h>
#include <sys/stat.h>
#include <sys/ioctl.h>
#include <sys/socket.h>
#ifdef HAVE_SYS_WAIT_H
#include <sys/wait.h>
#endif
#ifdef TIME_WITH_SYS_TIME
# include <sys/time.h>
# include <time.h>
#else
# ifdef HAVE_SYS_TIME_H
# include <sys/time.h>
# else
# include <time.h>
# endif
#endif
#ifdef HAVE_SYS_RESOURCE_H
#include <sys/resource.h>
#endif
#include <netinet/in.h>
#include <arpa/inet.h>
#include <dirent.h>
#include <errno.h>
#include <fcntl.h>
#include <netdb.h>
#include <pwd.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include <unistd.h>
#include <getopt.h>
#ifdef HAVE_SYS_SELECT_H
#include <sys/select.h>
#endif
#include <grp.h>
#define TOOMANY 40 /* don't start more than TOOMANY */
#define CNT_INTVL 60 /* servers in CNT_INTVL sec. */
#define RETRYTIME (60*10) /* retry after bind or server fail */
#ifndef SIGCHLD
#define SIGCHLD SIGCLD
#endif
#define SIGBLOCK (sigmask(SIGCHLD)|sigmask(SIGHUP)|sigmask(SIGALRM))
extern char *__progname;
int debug = 0;
int nsock, maxsock;
fd_set allsock;
int options;
int timingout;
int toomany = TOOMANY;
struct servtab {
char *se_service; /* name of service */
int se_socktype; /* type of socket to use */
char *se_proto; /* protocol used */
pid_t se_wait; /* single threaded server */
short se_checked; /* looked at during merge */
char *se_user; /* user name to run as */
struct biltin *se_bi; /* if built-in, description */
char *se_server; /* server program */
char **se_argv; /* program arguments */
size_t se_argc; /* number of arguments */
int se_fd; /* open descriptor */
int se_type; /* type */
sa_family_t se_family; /* address family of the socket */
char se_v4mapped; /* 1 = accept v4mapped connection, 0 = don't */
#ifdef IPV6
struct sockaddr_storage se_ctrladdr;/* bound address */
#else
struct sockaddr_in se_ctrladdr;/* bound address */
#endif
int se_count; /* number started since se_time */
struct timeval se_time; /* start of se_count */
struct servtab *se_next;
} *servtab;
#define NORM_TYPE 0
#define MUX_TYPE 1
#define MUXPLUS_TYPE 2
#define ISMUX(sep) (((sep)->se_type == MUX_TYPE) || \
((sep)->se_type == MUXPLUS_TYPE))
#define ISMUXPLUS(sep) ((sep)->se_type == MUXPLUS_TYPE)
void chargen_dg __P((int, struct servtab *));
void chargen_stream __P((int, struct servtab *));
void close_sep __P((struct servtab *));
void config __P((int));
void daytime_dg __P((int, struct servtab *));
void daytime_stream __P((int, struct servtab *));
void discard_dg __P((int, struct servtab *));
void discard_stream __P((int, struct servtab *));
void echo_dg __P((int, struct servtab *));
void echo_stream __P((int, struct servtab *));
void endconfig __P((FILE *));
struct servtab *enter __P((struct servtab *));
void freeconfig __P((struct servtab *));
struct servtab *getconfigent __P((FILE *, const char *, size_t *));
void machtime_dg __P((int, struct servtab *));
void machtime_stream __P((int, struct servtab *));
char *newstr __P((const char *));
char *nextline __P((FILE *));
void nextconfig __P((const char *));
void print_service __P((const char *, const char *, struct servtab *));
void reapchild __P((int));
void retry __P((int));
FILE *setconfig __P((const char *));
void setup __P((struct servtab *));
void tcpmux __P((int s, struct servtab *sep));
void set_proc_title __P ((char *, int));
void initring __P((void));
long machtime __P((void));
void run_service __P ((int ctrl, struct servtab *sep));
struct biltin {
const char *bi_service; /* internally provided service name */
int bi_socktype; /* type of socket supported */
short bi_fork; /* 1 if should fork before call */
short bi_wait; /* 1 if should wait for child */
void (*bi_fn) __P((int s, struct servtab *)); /*function which performs it */
} biltins[] = {
/* Echo received data */
{ "echo", SOCK_STREAM, 1, 0, echo_stream },
{ "echo", SOCK_DGRAM, 0, 0, echo_dg },
/* Internet /dev/null */
{ "discard", SOCK_STREAM, 1, 0, discard_stream },
{ "discard", SOCK_DGRAM, 0, 0, discard_dg },
/* Return 32 bit time since 1900 */
{ "time", SOCK_STREAM, 0, 0, machtime_stream },
{ "time", SOCK_DGRAM, 0, 0, machtime_dg },
/* Return human-readable time */
{ "daytime", SOCK_STREAM, 0, 0, daytime_stream },
{ "daytime", SOCK_DGRAM, 0, 0, daytime_dg },
/* Familiar character generator */
{ "chargen", SOCK_STREAM, 1, 0, chargen_stream },
{ "chargen", SOCK_DGRAM, 0, 0, chargen_dg },
{ "tcpmux", SOCK_STREAM, 1, 0, tcpmux },
{ NULL, 0, 0, 0, NULL }
};
#define NUMINT (sizeof(intab) / sizeof(struct inent))
char **Argv;
char *LastArg;
char **config_files;
/* Signal handling */
#if defined(HAVE_SIGACTION)
# define SIGSTATUS sigset_t
#else
# define SIGSTATUS long
#endif
void
signal_set_handler (int signo, RETSIGTYPE (*handler) ())
{
#if defined(HAVE_SIGACTION)
struct sigaction sa;
memset ((char *)&sa, 0, sizeof(sa));
sigemptyset (&sa.sa_mask);
sigaddset (&sa.sa_mask, signo);
#ifdef SA_RESTART
sa.sa_flags = SA_RESTART;
#endif
sa.sa_handler = handler;
sigaction (signo, &sa, NULL);
#elif defined(HAVE_SIGVEC)
struct sigvec sv;
memset (&sv, 0, sizeof(sv));
sv.sv_mask = SIGBLOCK;
sv.sv_handler = handler;
sigvec (signo, &sv, NULL);
#else /* !HAVE_SIGVEC */
signal (signo, handler);
#endif /* HAVE_SIGACTION */
}
void
signal_block (SIGSTATUS *old_status)
{
#ifdef HAVE_SIGACTION
sigset_t sigs;
sigemptyset (&sigs);
sigaddset (&sigs, SIGCHLD);
sigaddset (&sigs, SIGHUP);
sigaddset (&sigs, SIGALRM);
sigprocmask (SIG_BLOCK, &sigs, old_status);
#else
long omask = sigblock (SIGBLOCK);
if (old_status)
*old_status = omask;
#endif
}
void
signal_unblock (SIGSTATUS *status)
{
#ifdef HAVE_SIGACTION
if (status)
sigprocmask (SIG_SETMASK, status, 0);
else
{
sigset_t empty;
sigemptyset (&empty);
sigprocmask (SIG_SETMASK, &empty, 0);
}
#else
sigsetmask (status ? *status : 0);
#endif
}
static void
usage (int err)
{
if (err != 0)
{
fprintf (stderr, "Usage: %s [OPTION...] [CONF-FILE [CONF-DIR]] ...\n",
__progname);
fprintf (stderr, "Try `%s --help' for more information.\n", __progname);
}
else
{
fprintf (stdout, "Usage: %s [OPTION...] [CONF-FILE [CONF-DIR]] ...\n",
__progname);
puts ("Internet super-server.\n\n\
-d, --debug Debug mode\n\
-R, --rate NUMBER Maximum invocation rate (per second)\n\
--help Display this help and exit\n\
-V, --version Output version information and exit");
fprintf (stdout, "\nSubmit bug reports to %s.\n", PACKAGE_BUGREPORT);
}
exit (err);
}
static const char *short_options = "dR:V";
static struct option long_options[] =
{
{ "debug", no_argument, 0, 'd' },
{ "rate", required_argument, 0, 'R' },
{ "help", no_argument, 0, '&' },
{ "version", no_argument, 0, 'V' },
{ 0, 0, 0, 0 }
};
int
main (int argc, char *argv[], char *envp[])
{
int option;
struct servtab *sep;
int dofork;
pid_t pid;
#ifndef HAVE___PROGNAME
__progname = argv[0];
#endif
Argv = argv;
if (envp == 0 || *envp == 0)
envp = argv;
while (*envp)
envp++;
LastArg = envp[-1] + strlen (envp[-1]);
while ((option = getopt_long (argc, argv, short_options,
long_options, 0)) != EOF)
{
switch (option)
{
case 'd': /* Debug. */
debug = 1;
options |= SO_DEBUG;
break;
case 'R': /* Invocation rate. */
{
char *p;
int number;
number = strtol (optarg, &p, 0);
if (number < 1 || *p)
syslog (LOG_ERR,
"-R %s: bad value for service invocation rate",
optarg);
else
toomany = number;
break;
}
case '&': /* Usage. */
usage (0);
/* Not reached. */
case 'V': /* Version. */
printf ("inetd (%s) %s\n", PACKAGE_NAME, PACKAGE_VERSION);
exit (0);
/* Not reached. */
case '?':
default:
usage (1);
/* Not reached. */
}
}
if (optind < argc)
{
int i;
config_files = calloc (argc - optind + 1, sizeof (*config_files));
for (i = 0; optind < argc; optind++, i++)
{
config_files[i] = strdup (argv[optind]);
}
}
else
{
config_files = calloc (3, sizeof (*config_files));
config_files[0] = newstr (PATH_INETDCONF);
config_files[1] = newstr (PATH_INETDDIR);
}
if (debug == 0)
{
daemon (0, 0);
}
openlog ("inetd", LOG_PID | LOG_NOWAIT, LOG_DAEMON);
{
FILE *fp = fopen (PATH_INETDPID, "w");
if (fp != NULL)
{
fprintf (fp, "%d\n", getpid ());
(void) fclose (fp);
}
else
syslog (LOG_CRIT, "can't open %s: %s\n", PATH_INETDPID, strerror (errno));
}
signal_set_handler (SIGALRM, retry);
config (0);
signal_set_handler (SIGHUP, config);
signal_set_handler (SIGCHLD, reapchild);
signal_set_handler (SIGPIPE, SIG_IGN);
{
/* space for daemons to overwrite environment for ps */
#define DUMMYSIZE 100
char dummy[DUMMYSIZE];
memset(dummy, 'x', DUMMYSIZE - 1);
dummy[DUMMYSIZE - 1] = '\0';
setenv("inetd_dummy", dummy, 1);
}
for (;;)
{
int n, ctrl;
fd_set readable;
if (nsock == 0)
{
signal_block (NULL);
while (nsock == 0)
sigpause (0L);
signal_unblock (NULL);
}
readable = allsock;
if ((n = select (maxsock + 1, &readable, NULL, NULL, NULL)) <= 0)
{
if (n < 0 && errno != EINTR)
syslog (LOG_WARNING, "select: %m");
sleep (1);
continue;
}
for (sep = servtab; n && sep; sep = sep->se_next)
if (sep->se_fd != -1 && FD_ISSET (sep->se_fd, &readable))
{
n--;
if (debug)
fprintf (stderr, "someone wants %s\n", sep->se_service);
if (!sep->se_wait && sep->se_socktype == SOCK_STREAM)
{
ctrl = accept (sep->se_fd, NULL, NULL);
if (debug)
fprintf (stderr, "accept, ctrl %d\n", ctrl);
if (ctrl < 0)
{
if (errno != EINTR)
syslog (LOG_WARNING, "accept (for %s): %m",
sep->se_service);
continue;
}
}
else
ctrl = sep->se_fd;
signal_block (NULL);
pid = 0;
dofork = (sep->se_bi == 0 || sep->se_bi->bi_fork);
if (dofork)
{
if (sep->se_count++ == 0)
gettimeofday (&sep->se_time, NULL);
else if (sep->se_count >= toomany)
{
struct timeval now;
gettimeofday (&now, NULL);
if (now.tv_sec - sep->se_time.tv_sec > CNT_INTVL)
{
sep->se_time = now;
sep->se_count = 1;
}
else
{
syslog (LOG_ERR,
"%s/%s server failing (looping), service terminated",
sep->se_service, sep->se_proto);
close_sep (sep);
signal_unblock (NULL);
if (!timingout)
{
timingout = 1;
alarm (RETRYTIME);
}
continue;
}
}
pid = fork ();
}
if (pid < 0)
{
syslog (LOG_ERR, "fork: %m");
if (!sep->se_wait && sep->se_socktype == SOCK_STREAM)
close (ctrl);
signal_unblock (NULL);
sleep (1);
continue;
}
if (pid && sep->se_wait)
{
sep->se_wait = pid;
if (sep->se_fd >= 0)
{
FD_CLR (sep->se_fd, &allsock);
nsock--;
}
}
signal_unblock (NULL);
if (pid == 0)
{
if (debug && dofork)
setsid ();
if (dofork)
{
int sock;
if (debug)
fprintf (stderr, "+ Closing from %d\n", maxsock);
for (sock = maxsock; sock > 2; sock--)
if (sock != ctrl)
close (sock);
}
run_service (ctrl, sep);
}
if (!sep->se_wait && sep->se_socktype == SOCK_STREAM)
close (ctrl);
}
}
}
void
run_service (int ctrl, struct servtab *sep)
{
struct passwd *pwd;
char buf[50];
if (sep->se_bi)
{
(*sep->se_bi->bi_fn) (ctrl, sep);
}
else
{
if (debug)
fprintf (stderr, "%d execl %s\n", getpid (), sep->se_server);
dup2 (ctrl, 0);
close (ctrl);
dup2 (0, 1);
dup2 (0, 2);
if ((pwd = getpwnam (sep->se_user)) == NULL)
{
syslog (LOG_ERR, "%s/%s: %s: No such user",
sep->se_service, sep->se_proto, sep->se_user);
if (sep->se_socktype != SOCK_STREAM)
recv (0, buf, sizeof buf, 0);
_exit (1);
}
if (pwd->pw_uid)
{
if (setgid (pwd->pw_gid) < 0)
{
syslog (LOG_ERR, "%s: can't set gid %d: %m",
sep->se_service, pwd->pw_gid);
_exit (1);
}
#ifdef HAVE_INITGROUPS
initgroups (pwd->pw_name, pwd->pw_gid);
#endif
if (setuid (pwd->pw_uid) < 0)
{
syslog (LOG_ERR, "%s: can't set uid %d: %m",
sep->se_service, pwd->pw_uid);
_exit (1);
}
}
execv (sep->se_server, sep->se_argv);
if (sep->se_socktype != SOCK_STREAM)
recv (0, buf, sizeof buf, 0);
syslog (LOG_ERR, "cannot execute %s: %m", sep->se_server);
_exit (1);
}
}
void
reapchild (int signo)
{
int status;
pid_t pid;
struct servtab *sep;
(void)signo; /* shutup gcc */
for (;;)
{
#ifdef HAVE_WAIT3
pid = wait3 (&status, WNOHANG, NULL);
#else
pid = wait (&status);
#endif
if (pid <= 0)
break;
if (debug)
fprintf (stderr, "%d reaped, status %#x\n", pid, status);
for (sep = servtab; sep; sep = sep->se_next)
if (sep->se_wait == pid)
{
if (status)
syslog (LOG_WARNING, "%s: exit status 0x%x",
sep->se_server, status);
if (debug)
fprintf (stderr, "restored %s, fd %d\n",
sep->se_service, sep->se_fd);
FD_SET (sep->se_fd, &allsock);
nsock++;
sep->se_wait = 1;
}
}
}
void
config (int signo)
{
int i;
struct stat stats;
struct servtab *sep;
(void)signo; /* Shutup gcc. */
for (sep = servtab; sep; sep = sep->se_next)
sep->se_checked = 0;
for (i = 0; config_files[i]; i++)
{
struct stat statbuf;
if (stat (config_files[i], &statbuf) == 0)
{
if (S_ISDIR (statbuf.st_mode))
{
DIR *dirp = opendir (config_files[i]);
if (dirp)
{
struct dirent *dp;
while ((dp = readdir (dirp)) != NULL)
{
char *path = calloc (strlen (config_files[i])
+ strlen (dp->d_name) + 2, 1);
if (path)
{
sprintf (path,"%s/%s", config_files[i], dp->d_name);
if (stat (path, &stats) == 0
&& S_ISREG(stats.st_mode))
{
nextconfig (path);
}
free (path);
}
}
closedir (dirp);
}
}
else if (S_ISREG (statbuf.st_mode))
{
nextconfig (config_files[i]);
}
}
else
{
if (signo == 0)
fprintf (stderr, "inetd: %s, %s\n",
config_files[i], strerror(errno));
else
syslog (LOG_ERR, "%s: %m", config_files[i]);
}
}
}
void
nextconfig (const char *file)
{
#ifndef IPV6
struct servent *sp;
#endif
struct servtab *sep, *cp, **sepp;
struct passwd *pwd;
FILE * fconfig;
SIGSTATUS sigstatus;
size_t line = 0;
fconfig = setconfig (file);
if (!fconfig)
{
syslog (LOG_ERR, "%s: %m", file);
return;
}
while ((cp = getconfigent (fconfig, file, &line)))
{
if ((pwd = getpwnam (cp->se_user)) == NULL)
{
syslog(LOG_ERR, "%s/%s: No such user '%s', service ignored",
cp->se_service, cp->se_proto, cp->se_user);
continue;
}
/* Checking/Removing duplicates */
for (sep = servtab; sep; sep = sep->se_next)
if (strcmp (sep->se_service, cp->se_service) == 0
&& strcmp (sep->se_proto, cp->se_proto) == 0
&& ISMUX(sep) == ISMUX (cp))
break;
if (sep != 0)
{
signal_block (&sigstatus);
/*
* sep->se_wait may be holding the pid of a daemon
* that we're waiting for. If so, don't overwrite
* it unless the config file explicitly says don't
* wait.
*/
if (cp->se_bi == 0
&& (sep->se_wait == 1 || cp->se_wait == 0))
sep->se_wait = cp->se_wait;
#define SWAP(a, b) { char *c = a; a = b; b = c; }
if (cp->se_user)
SWAP(sep->se_user, cp->se_user);
if (cp->se_server)
SWAP(sep->se_server, cp->se_server);
argcv_free(sep->se_argc, sep->se_argv);
sep->se_argc = cp->se_argc;
sep->se_argv = cp->se_argv;
cp->se_argc = 0;
cp->se_argv = NULL;
signal_unblock (&sigstatus);
freeconfig (cp);
if (debug)
print_service (file, "REDO", sep);
}
else
{
sep = enter (cp);
if (debug)
print_service (file, "ADD ", sep);
}
sep->se_checked = 1;
if (ISMUX (sep))
{
sep->se_fd = -1;
continue;
}
#ifndef IPV6 /* This code is moved to setup() for IPV6. */
sp = getservbyname (sep->se_service, sep->se_proto);
if (sp == 0)
{
syslog (LOG_ERR, "%s/%s: unknown service",
sep->se_service, sep->se_proto);
sep->se_checked = 0;
continue;
}
if (sp->s_port != sep->se_ctrladdr.sin_port)
{
sep->se_ctrladdr.sin_family = AF_INET;
sep->se_ctrladdr.sin_port = sp->s_port;
if (sep->se_fd >= 0)
close_sep (sep);
}
#endif
if (sep->se_fd == -1)
setup (sep);
}
endconfig (fconfig);
/*
* Purge anything not looked at above.
*/
signal_block (&sigstatus);
sepp = &servtab;
while ((sep = *sepp))
{
if (sep->se_checked)
{
sepp = &sep->se_next;
continue;
}
*sepp = sep->se_next;
if (sep->se_fd >= 0)
close_sep (sep);
if (debug)
print_service (file, "FREE", sep);
freeconfig (sep);
free ((char *)sep);
}
signal_unblock (&sigstatus);
}
void
retry (int signo)
{
struct servtab *sep;
(void)signo; /* shutup gcc */
timingout = 0;
for (sep = servtab; sep; sep = sep->se_next)
if (sep->se_fd == -1 && !ISMUX (sep))
setup (sep);
}
void
setup (struct servtab *sep)
{
int err;
const int on = 1;
#ifdef IPV6
const int off = 0;
struct addrinfo *result, hints;
struct protoent *proto;
tryagain:
#endif
sep->se_fd = socket (sep->se_family, sep->se_socktype, 0);
if (sep->se_fd < 0)
{
#ifdef IPV6
/* If we don't support creating AF_INET6 sockets, create AF_INET
sockets. */
if (errno == EAFNOSUPPORT && sep->se_family == AF_INET6 && sep->se_v4mapped)
{
/* Fall back to IPv6 silently. */
sep->se_family = AF_INET;
goto tryagain;
}
#endif
if (debug)
fprintf (stderr, "socket failed on %s/%s: %s\n",
sep->se_service, sep->se_proto, strerror (errno));
syslog(LOG_ERR, "%s/%s: socket: %m", sep->se_service, sep->se_proto);
return;
}
#ifdef IPV6
/* Make sure that tcp6 etc also work. */
if (strncmp (sep->se_proto, "tcp", 3) == 0)
proto = getprotobyname ("tcp");
else if (strncmp (sep->se_proto, "udp", 3) == 0)
proto = getprotobyname ("udp");
else
proto = getprotobyname (sep->se_proto);
if (!proto)
{
syslog (LOG_ERR, "%s: Unknown protocol", sep->se_proto);
close (sep->se_fd);
sep->se_fd = -1;
return;
}
memset (&hints, 0, sizeof (hints));
hints.ai_flags = AI_PASSIVE;
hints.ai_family = sep->se_family;
hints.ai_socktype = sep->se_socktype;
hints.ai_protocol = proto->p_proto;
err = getaddrinfo (NULL, sep->se_service, &hints, &result);
if (err)
{
const char *errmsg;
if (err == EAI_FAMILY && sep->se_family == AF_INET6 && sep->se_v4mapped)
{
/* Fall back to IPv6 silently. */
sep->se_family = AF_INET;
close (sep->se_fd);
goto tryagain;
}
if (err == EAI_SYSTEM)
errmsg = strerror (errno);
else
errmsg = gai_strerror (err);
syslog (LOG_ERR, "%s/%s: getaddrinfo: %s",
sep->se_service, sep->se_proto, errmsg);
close (sep->se_fd);
sep->se_fd = -1;
return;
}
memcpy (&sep->se_ctrladdr, result->ai_addr, result->ai_addrlen);
freeaddrinfo (result);
if (sep->se_family == AF_INET6)
{
if (sep->se_v4mapped)
err = setsockopt (sep->se_fd, IPPROTO_IPV6, IPV6_V6ONLY,
(char *)&off, sizeof(off));
else
err = setsockopt (sep->se_fd, IPPROTO_IPV6, IPV6_V6ONLY,
(char *)&on, sizeof(on));
if (err < 0)
syslog (LOG_ERR, "setsockopt (IPV6_V6ONLY): %m");
}
#endif
if (strncmp (sep->se_proto, "tcp", 3) == 0 && (options & SO_DEBUG))
{
err = setsockopt(sep->se_fd, SOL_SOCKET, SO_DEBUG,
(char *)&on, sizeof (on));
if (err < 0)
syslog (LOG_ERR, "setsockopt (SO_DEBUG): %m");
}
err = setsockopt(sep->se_fd, SOL_SOCKET, SO_REUSEADDR,
(char *)&on, sizeof (on));
if (err < 0)
syslog (LOG_ERR, "setsockopt (SO_REUSEADDR): %m");
err = bind (sep->se_fd, (struct sockaddr *)&sep->se_ctrladdr,
sizeof (sep->se_ctrladdr));
if (err < 0)
{
#ifdef IPV6
/* If we can't bind with AF_INET6 try again with AF_INET. */
if ((errno == EADDRNOTAVAIL || errno == EAFNOSUPPORT)
&& sep->se_family == AF_INET6 && sep->se_v4mapped)
{
/* Fall back to IPv6 silently. */
sep->se_family = AF_INET;
close (sep->se_fd);
goto tryagain;
}
#endif
if (debug)
fprintf (stderr, "bind failed on %s/%s: %s\n",
sep->se_service, sep->se_proto, strerror (errno));
syslog(LOG_ERR, "%s/%s: bind: %m", sep->se_service, sep->se_proto);
close (sep->se_fd);
sep->se_fd = -1;
if (!timingout)
{
timingout = 1;
alarm (RETRYTIME);
}
return;
}
if (sep->se_socktype == SOCK_STREAM)
listen (sep->se_fd, 10);
FD_SET (sep->se_fd, &allsock);
nsock++;
if (sep->se_fd > maxsock)
maxsock = sep->se_fd;
if (debug)
{
fprintf(stderr, "registered %s on %d\n", sep->se_server, sep->se_fd);
}
}
/*
* Finish with a service and its socket.
*/
void
close_sep (struct servtab *sep)
{
if (sep->se_fd >= 0)
{
nsock--;
FD_CLR (sep->se_fd, &allsock);
close (sep->se_fd);
sep->se_fd = -1;
}
sep->se_count = 0;
/*
* Don't keep the pid of this running deamon: when reapchild()
* reaps this pid, it would erroneously increment nsock.
*/
if (sep->se_wait > 1)
sep->se_wait = 1;
}
struct servtab *
enter (struct servtab *cp)
{
struct servtab *sep;
SIGSTATUS sigstatus;
sep = (struct servtab *)malloc (sizeof (*sep));
if (sep == NULL)
{
syslog (LOG_ERR, "Out of memory.");
exit (-1);
}
*sep = *cp;
sep->se_fd = -1;
signal_block (&sigstatus);
sep->se_next = servtab;
servtab = sep;
signal_unblock (&sigstatus);
return sep;
}
struct servtab serv;
#ifdef LINE_MAX
char line[LINE_MAX];
#else
char line[2048];
#endif
FILE *
setconfig (const char *file)
{
return fopen (file, "r");
}
void
endconfig (FILE *fconfig)
{
if (fconfig)
{
fclose (fconfig);
}
}
#define INETD_SERVICE 0 /* service name */
#define INETD_SOCKET 1 /* socket type */
#define INETD_PROTOCOL 2 /* protocol */
#define INETD_WAIT 3 /* wait/nowait */
#define INETD_USER 4 /* user */
#define INETD_SERVER_PATH 5 /* server program path */
#define INETD_SERVER_ARGS 6 /* server program arguments */
#define INETD_FIELDS_MIN 6 /* Minimum number of fields in entry */
struct servtab *
getconfigent (FILE *fconfig, const char *file, size_t *line)
{
struct servtab *sep = &serv;
size_t argc = 0, i;
char **argv = NULL;
char *cp;
static char TCPMUX_TOKEN[] = "tcpmux/";
#define MUX_LEN (sizeof(TCPMUX_TOKEN)-1)
memset ((caddr_t)sep, 0, sizeof *sep);
while (1)
{
argcv_free (argc, argv);
freeconfig (sep);
memset ((caddr_t)sep, 0, sizeof *sep);
while ((cp = nextline (fconfig)) && (*cp == '#' || *cp == '\0'))
++*line;
++*line;
if (cp == NULL)
return NULL;
if (argcv_get (cp, "", &argc, &argv))
continue;
if (argc < INETD_FIELDS_MIN)
{
syslog (LOG_ERR, "%s:%lu: not enough fields",
file, (unsigned long) *line);
continue;
}
if (strncmp (argv[INETD_SERVICE], TCPMUX_TOKEN, MUX_LEN) == 0)
{
char *c = argv[INETD_SERVICE] + MUX_LEN;
if (*c == '+')
{
sep->se_type = MUXPLUS_TYPE;
c++;
}
else
sep->se_type = MUX_TYPE;
sep->se_service = newstr (c);
}
else
{
sep->se_service = newstr (argv[INETD_SERVICE]);
sep->se_type = NORM_TYPE;
}
if (strcmp (argv[INETD_SOCKET], "stream") == 0)
sep->se_socktype = SOCK_STREAM;
else if (strcmp (argv[INETD_SOCKET], "dgram") == 0)
sep->se_socktype = SOCK_DGRAM;
else if (strcmp (argv[INETD_SOCKET], "rdm") == 0)
sep->se_socktype = SOCK_RDM;
else if (strcmp (argv[INETD_SOCKET], "seqpacket") == 0)
sep->se_socktype = SOCK_SEQPACKET;
else if (strcmp (argv[INETD_SOCKET], "raw") == 0)
sep->se_socktype = SOCK_RAW;
else
{
syslog (LOG_WARNING, "%s:%lu: bad socket type",
file, (unsigned long) *line);
sep->se_socktype = -1;
}
sep->se_proto = newstr (argv[INETD_PROTOCOL]);
#ifdef IPV6
/* We default to IPv6, in setup() we'll fall back to IPv4 if
it doesn't work. */
sep->se_family = AF_INET6;
sep->se_v4mapped = 1;
if ((strncmp (sep->se_proto, "tcp", 3) == 0)
|| (strncmp (sep->se_proto, "udp", 3) == 0))
{
if (sep->se_proto[3] == '6')
{
sep->se_family = AF_INET6;
sep->se_v4mapped = 0;
}
else if (sep->se_proto[3] == '4')
{
sep->se_family = AF_INET;
}
}
#else
if ((strncmp (sep->se_proto, "tcp6", 4) == 0)
|| (strncmp (sep->se_proto, "udp6", 4) == 0))
{
syslog (LOG_ERR, "%s:%lu: %s: IPv6 support isn't eneabled",
file, (unsigned long) *line, sep->se_proto);
continue;
}
sep->se_family = AF_INET;
#endif
if (strcmp (argv[INETD_WAIT], "wait") == 0)
sep->se_wait = 1;
else if (strcmp (argv[INETD_WAIT], "nowait") == 0)
sep->se_wait = 0;
else
{
syslog (LOG_WARNING, "%s:%lu: bad wait type",
file, (unsigned long) *line);
}
if (ISMUX (sep))
{
/*
* Silently enforce "nowait" for TCPMUX services since
* they don't have an assigned port to listen on.
*/
sep->se_wait = 0;
if (strncmp (sep->se_proto, "tcp", 3))
{
syslog (LOG_ERR, "%s:%lu: bad protocol for tcpmux service %s",
file, (unsigned long) *line, sep->se_service);
continue;
}
if (sep->se_socktype != SOCK_STREAM)
{
syslog (LOG_ERR,
"%s:%lu: bad socket type for tcpmux service %s",
file, (unsigned long) *line, sep->se_service);
continue;
}
}
sep->se_user = newstr (argv[INETD_USER]);
sep->se_server = newstr (argv[INETD_SERVER_PATH]);
if (strcmp (sep->se_server, "internal") == 0)
{
struct biltin *bi;
for (bi = biltins; bi->bi_service; bi++)
if (bi->bi_socktype == sep->se_socktype
&& strcmp (bi->bi_service, sep->se_service) == 0)
break;
if (bi->bi_service == 0)
{
syslog (LOG_ERR, "%s:%lu: internal service %s unknown",
file, (unsigned long) *line, sep->se_service);
continue;
}
sep->se_bi = bi;
sep->se_wait = bi->bi_wait;
} else
sep->se_bi = NULL;
sep->se_argc = argc - INETD_FIELDS_MIN + 1;
sep->se_argv = calloc (sep->se_argc + 1, sizeof sep->se_argv[0]);
if (!sep->se_argv)
{
syslog (LOG_ERR, "%s:%lu: Out of memory.",
file, (unsigned long) *line);
exit (-1);
}
for (i = 0; i < sep->se_argc; i++)
{
sep->se_argv[i] = argv[INETD_SERVER_ARGS + i];
argv[INETD_SERVER_ARGS + i] = 0;
}
sep->se_argv[i] = NULL;
break;
}
argcv_free (argc, argv);
return sep;
}
void
freeconfig (struct servtab *cp)
{
if (cp->se_service)
free (cp->se_service);
if (cp->se_proto)
free (cp->se_proto);
if (cp->se_user)
free (cp->se_user);
if (cp->se_server)
free (cp->se_server);
argcv_free(cp->se_argc, cp->se_argv);
}
char *
nextline (FILE *fd)
{
char *cp;
if (fgets (line, sizeof line, fd) == NULL)
return NULL;
cp = strchr (line, '\n');
if (cp)
*cp = '\0';
return line;
}
char *
newstr (const char *cp)
{
char *s;
if ((s = strdup (cp ? cp : "")))
return s;
syslog (LOG_ERR, "strdup: %m");
exit (-1);
}
void
set_proc_title (char *a, int s)
{
int size;
char *cp;
#ifdef IPV6
struct sockaddr_storage saddr;
#else
struct sockaddr_in saddr;
#endif
char buf[80];
cp = Argv[0];
size = sizeof saddr;
if (getpeername (s, (struct sockaddr *)&saddr, &size) == 0)
{
#ifdef IPV6
int err;
char buf2[80];
err = getnameinfo ((struct sockaddr *) &saddr, sizeof (saddr), buf2,
sizeof (buf2), NULL, 0, NI_NUMERICHOST);
if (!err)
snprintf (buf, sizeof buf, "-%s [%s]", a, buf2);
else
snprintf (buf, sizeof buf, "-%s", a);
#else
snprintf (buf, sizeof buf, "-%s [%s]", a, inet_ntoa (saddr.sin_addr));
#endif
}
else
snprintf (buf, sizeof buf, "-%s", a);
strncpy (cp, buf, LastArg - cp);
cp += strlen (cp);
while (cp < LastArg)
*cp++ = ' ';
}
/*
* Internet services provided internally by inetd:
*/
#define BUFSIZE 8192
/* ARGSUSED */
/* Echo service -- echo data back */
void
echo_stream (int s, struct servtab *sep)
{
char buffer[BUFSIZE];
int i;
set_proc_title (sep->se_service, s);
while ((i = read (s, buffer, sizeof buffer)) > 0
&& write (s, buffer, i) > 0)
;
exit (0);
}
/* ARGSUSED */
/* Echo service -- echo data back */
void
echo_dg (int s, struct servtab *sep)
{
char buffer[BUFSIZE];
int i, size;
#ifdef IPV6
struct sockaddr_storage sa;
#else
struct sockaddr sa;
#endif
(void)sep;
size = sizeof sa;
i = recvfrom (s, buffer, sizeof buffer, 0, (struct sockaddr *)&sa, &size);
if (i < 0)
return;
sendto (s, buffer, i, 0, (struct sockaddr *) &sa, sizeof sa);
}
/* ARGSUSED */
/* Discard service -- ignore data */
void
discard_stream (int s, struct servtab *sep)
{
int ret;
char buffer[BUFSIZE];
set_proc_title (sep->se_service, s);
while (1)
{
while ((ret = read (s, buffer, sizeof buffer)) > 0)
;
if (ret == 0 || errno != EINTR)
break;
}
exit (0);
}
/* ARGSUSED */
void
/* Discard service -- ignore data */
discard_dg (int s, struct servtab *sep)
{
char buffer[BUFSIZE];
(void)sep; /* shutup gcc */
read (s, buffer, sizeof buffer);
}
#include <ctype.h>
#define LINESIZ 72
char ring[128];
char *endring;
void
initring (void)
{
int i;
endring = ring;
for (i = 0; i <= 128; ++i)
if (isprint (i))
*endring++ = i;
}
/* ARGSUSED */
/* Character generator */
void
chargen_stream (int s, struct servtab *sep)
{
int len;
char *rs, text[LINESIZ+2];
set_proc_title (sep->se_service, s);
if (!endring)
{
initring ();
rs = ring;
}
text[LINESIZ] = '\r';
text[LINESIZ + 1] = '\n';
for (rs = ring;;)
{
if ((len = endring - rs) >= LINESIZ)
memmove (text, rs, LINESIZ);
else
{
memmove (text, rs, len);
memmove (text + len, ring, LINESIZ - len);
}
if (++rs == endring)
rs = ring;
if (write (s, text, sizeof text) != sizeof text)
break;
}
exit (0);
}
/* ARGSUSED */
/* Character generator */
void
chargen_dg (int s, struct servtab *sep)
{
#ifdef IPV6
struct sockaddr_storage sa;
#else
struct sockaddr sa;
#endif
static char *rs;
int len, size;
char text[LINESIZ+2];
(void)sep; /* shutup gcc */
if (endring == 0)
{
initring ();
rs = ring;
}
size = sizeof sa;
if (recvfrom (s, text, sizeof text, 0, (struct sockaddr *)&sa, &size) < 0)
return;
if ((len = endring - rs) >= LINESIZ)
memmove (text, rs, LINESIZ);
else
{
memmove (text, rs, len);
memmove (text + len, ring, LINESIZ - len);
}
if (++rs == endring)
rs = ring;
text[LINESIZ] = '\r';
text[LINESIZ + 1] = '\n';
sendto (s, text, sizeof text, 0, (struct sockaddr *)&sa, sizeof sa);
}
/*
* Return a machine readable date and time, in the form of the
* number of seconds since midnight, Jan 1, 1900. Since gettimeofday
* returns the number of seconds since midnight, Jan 1, 1970,
* we must add 2208988800 seconds to this figure to make up for
* some seventy years Bell Labs was asleep.
*/
long
machtime (void)
{
struct timeval tv;
if (gettimeofday (&tv, NULL) < 0)
{
if (debug)
fprintf (stderr, "Unable to get time of day\n");
return 0L;
}
#define OFFSET ((u_long)25567 * 24*60*60)
return (htonl ((long)(tv.tv_sec + OFFSET)));
#undef OFFSET
}
/* ARGSUSED */
void
machtime_stream (int s, struct servtab *sep)
{
long result;
(void)sep; /* shutup gcc */
result = machtime ();
write (s, (char *) &result, sizeof result);
}
/* ARGSUSED */
void
machtime_dg (int s, struct servtab *sep)
{
long result;
#ifdef IPV6
struct sockaddr_storage sa;
#else
struct sockaddr sa;
#endif
int size;
(void)sep; /* shutup gcc */
size = sizeof sa;
if (recvfrom (s, (char *)&result, sizeof result, 0,
(struct sockaddr *)&sa, &size) < 0)
return;
result = machtime ();
sendto (s, (char *) &result, sizeof result, 0,
(struct sockaddr *)&sa, sizeof sa);
}
/* ARGSUSED */
void
/* Return human-readable time of day */
daytime_stream (int s, struct servtab *sep)
{
char buffer[256];
time_t lclock;
(void)sep; /*shutup gcc*/
lclock = time ((time_t *) 0);
sprintf (buffer, "%.24s\r\n", ctime(&lclock));
write (s, buffer, strlen(buffer));
}
/* ARGSUSED */
/* Return human-readable time of day */
void
daytime_dg(int s, struct servtab *sep)
{
char buffer[256];
time_t lclock;
#ifdef IPV6
struct sockaddr_storage sa;
#else
struct sockaddr sa;
#endif
int size;
(void)sep; /* shutup gcc */
lclock = time ((time_t *) 0);
size = sizeof sa;
if (recvfrom (s, buffer, sizeof buffer, 0, (struct sockaddr *)&sa, &size) < 0)
return;
sprintf (buffer, "%.24s\r\n", ctime (&lclock));
sendto (s, buffer, strlen(buffer), 0, (struct sockaddr *)&sa, sizeof sa);
}
/*
* print_service:
* Dump relevant information to stderr
*/
void
print_service (const char *file, const char *action, struct servtab *sep)
{
fprintf (stderr,
"%s:%s: %s proto=%s, wait=%d, user=%s builtin=%lx server=%s\n",
file, action, sep->se_service, sep->se_proto,
sep->se_wait, sep->se_user, (long)sep->se_bi, sep->se_server);
}
/*
* Based on TCPMUX.C by Mark K. Lottor November 1988
* sri-nic::ps:<mkl>tcpmux.c
*/
/* # of characters upto \r,\n or \0 */
static int
fd_getline (int fd, char *buf, int len)
{
int count = 0, n;
do {
n = read (fd, buf, len-count);
if (n == 0)
return count;
if (n < 0)
return -1;
while (--n >= 0)
{
if (*buf == '\r' || *buf == '\n' || *buf == '\0')
return count;
count++;
buf++;
}
} while (count < len);
return count;
}
#define MAX_SERV_LEN (256+2) /* 2 bytes for \r\n */
#define strwrite(fd, buf) write(fd, buf, sizeof(buf)-1)
void
tcpmux(int s, struct servtab *sep)
{
char service[MAX_SERV_LEN+1];
int len;
/* Get requested service name */
if ((len = fd_getline (s, service, MAX_SERV_LEN)) < 0)
{
strwrite (s, "-Error reading service name\r\n");
_exit (1);
}
service[len] = '\0';
if (debug)
fprintf (stderr, "tcpmux: someone wants %s\n", service);
/*
* Help is a required command, and lists available services,
* one per line.
*/
if (!strcasecmp (service, "help"))
{
for (sep = servtab; sep; sep = sep->se_next)
{
if (!ISMUX (sep))
continue;
write (s, sep->se_service, strlen (sep->se_service));
strwrite (s, "\r\n");
}
_exit (1);
}
/* Try matching a service in inetd.conf with the request */
for (sep = servtab; sep; sep = sep->se_next)
{
if (!ISMUX (sep))
continue;
if (!strcasecmp (service, sep->se_service))
{
if (ISMUXPLUS (sep))
{
strwrite (s, "+Go\r\n");
}
run_service (s, sep);
return;
}
}
strwrite (s, "-Service not available\r\n");
exit (1);
}