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inetd.c revision 1.4
      1 /*
      2  * Copyright (c) 1983,1991 The Regents of the University of California.
      3  * All rights reserved.
      4  *
      5  * Redistribution and use in source and binary forms, with or without
      6  * modification, are permitted provided that the following conditions
      7  * are met:
      8  * 1. Redistributions of source code must retain the above copyright
      9  *    notice, this list of conditions and the following disclaimer.
     10  * 2. Redistributions in binary form must reproduce the above copyright
     11  *    notice, this list of conditions and the following disclaimer in the
     12  *    documentation and/or other materials provided with the distribution.
     13  * 3. All advertising materials mentioning features or use of this software
     14  *    must display the following acknowledgement:
     15  *	This product includes software developed by the University of
     16  *	California, Berkeley and its contributors.
     17  * 4. Neither the name of the University nor the names of its contributors
     18  *    may be used to endorse or promote products derived from this software
     19  *    without specific prior written permission.
     20  *
     21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     31  * SUCH DAMAGE.
     32  */
     33 
     34 #ifndef lint
     35 char copyright[] =
     36 "@(#) Copyright (c) 1983 Regents of the University of California.\n\
     37  All rights reserved.\n";
     38 #endif /* not lint */
     39 
     40 #ifndef lint
     41 /*static char sccsid[] = "from: @(#)inetd.c	5.30 (Berkeley) 6/3/91";*/
     42 static char rcsid[] = "$Id: inetd.c,v 1.4 1993/10/11 20:53:48 mycroft Exp $";
     43 #endif /* not lint */
     44 
     45 /*
     46  * Inetd - Internet super-server
     47  *
     48  * This program invokes all internet services as needed.
     49  * connection-oriented services are invoked each time a
     50  * connection is made, by creating a process.  This process
     51  * is passed the connection as file descriptor 0 and is
     52  * expected to do a getpeername to find out the source host
     53  * and port.
     54  *
     55  * Datagram oriented services are invoked when a datagram
     56  * arrives; a process is created and passed a pending message
     57  * on file descriptor 0.  Datagram servers may either connect
     58  * to their peer, freeing up the original socket for inetd
     59  * to receive further messages on, or ``take over the socket'',
     60  * processing all arriving datagrams and, eventually, timing
     61  * out.	 The first type of server is said to be ``multi-threaded'';
     62  * the second type of server ``single-threaded''.
     63  *
     64  * Inetd uses a configuration file which is read at startup
     65  * and, possibly, at some later time in response to a hangup signal.
     66  * The configuration file is ``free format'' with fields given in the
     67  * order shown below.  Continuation lines for an entry must being with
     68  * a space or tab.  All fields must be present in each entry.
     69  *
     70  *	service name			must be in /etc/services
     71  *	socket type			stream/dgram/raw/rdm/seqpacket
     72  *	protocol			must be in /etc/protocols
     73  *	wait/nowait			single-threaded/multi-threaded
     74  *	user				user to run daemon as
     75  *	server program			full path name
     76  *	server program arguments	maximum of MAXARGS (20)
     77  *
     78  * For RPC services
     79  *      service name/version            must be in /etc/rpc
     80  *	socket type			stream/dgram/raw/rdm/seqpacket
     81  *	protocol			must be in /etc/protocols
     82  *	wait/nowait			single-threaded/multi-threaded
     83  *	user				user to run daemon as
     84  *	server program			full path name
     85  *	server program arguments	maximum of MAXARGS (20)
     86  *
     87  * Comment lines are indicated by a `#' in column 1.
     88  */
     89 #include <sys/param.h>
     90 #include <sys/stat.h>
     91 #include <sys/ioctl.h>
     92 #include <sys/socket.h>
     93 #include <sys/file.h>
     94 #include <sys/wait.h>
     95 #include <sys/time.h>
     96 #include <sys/resource.h>
     97 
     98 #include <netinet/in.h>
     99 #include <arpa/inet.h>
    100 
    101 #include <errno.h>
    102 #include <signal.h>
    103 #include <netdb.h>
    104 #include <syslog.h>
    105 #include <pwd.h>
    106 #include <stdio.h>
    107 #include <string.h>
    108 #include <rpc/rpc.h>
    109 #include "pathnames.h"
    110 
    111 #define	TOOMANY		40		/* don't start more than TOOMANY */
    112 #define	CNT_INTVL	60		/* servers in CNT_INTVL sec. */
    113 #define	RETRYTIME	(60*10)		/* retry after bind or server fail */
    114 
    115 #define	SIGBLOCK	(sigmask(SIGCHLD)|sigmask(SIGHUP)|sigmask(SIGALRM))
    116 
    117 void	config(), reapchild(), retry(), unregisterrpc();
    118 
    119 int	debug = 0;
    120 int	nsock, maxsock;
    121 fd_set	allsock;
    122 int	options;
    123 int	timingout;
    124 struct	servent *sp;
    125 struct	rpcent *rpc;
    126 
    127 struct	servtab {
    128 	char	*se_service;		/* name of service */
    129 	int	se_socktype;		/* type of socket to use */
    130 	char	*se_proto;		/* protocol used */
    131 	short	se_wait;		/* single threaded server */
    132 	short	se_checked;		/* looked at during merge */
    133 	char	*se_user;		/* user name to run as */
    134 	struct	biltin *se_bi;		/* if built-in, description */
    135 	char	*se_server;		/* server program */
    136 #define	MAXARGV 20
    137 	char	*se_argv[MAXARGV+1];	/* program arguments */
    138 	int	se_fd;			/* open descriptor */
    139 	struct	sockaddr_in se_ctrladdr;/* bound address */
    140 	int	se_rpc;			/* ==1 if this is an RPC service */
    141         int	se_rpc_prog;		/* RPC program number */
    142         u_int	se_rpc_lowvers;		/* RPC low version */
    143         u_int	se_rpc_highvers;	/* RPC high version */
    144 	int	se_count;		/* number started since se_time */
    145 	struct	timeval se_time;	/* start of se_count */
    146 	struct	servtab *se_next;
    147 } *servtab;
    148 
    149 int echo_stream(), discard_stream(), machtime_stream();
    150 int daytime_stream(), chargen_stream();
    151 int echo_dg(), discard_dg(), machtime_dg(), daytime_dg(), chargen_dg();
    152 
    153 struct biltin {
    154 	char	*bi_service;		/* internally provided service name */
    155 	int	bi_socktype;		/* type of socket supported */
    156 	short	bi_fork;		/* 1 if should fork before call */
    157 	short	bi_wait;		/* 1 if should wait for child */
    158 	int	(*bi_fn)();		/* function which performs it */
    159 } biltins[] = {
    160 	/* Echo received data */
    161 	"echo",		SOCK_STREAM,	1, 0,	echo_stream,
    162 	"echo",		SOCK_DGRAM,	0, 0,	echo_dg,
    163 
    164 	/* Internet /dev/null */
    165 	"discard",	SOCK_STREAM,	1, 0,	discard_stream,
    166 	"discard",	SOCK_DGRAM,	0, 0,	discard_dg,
    167 
    168 	/* Return 32 bit time since 1970 */
    169 	"time",		SOCK_STREAM,	0, 0,	machtime_stream,
    170 	"time",		SOCK_DGRAM,	0, 0,	machtime_dg,
    171 
    172 	/* Return human-readable time */
    173 	"daytime",	SOCK_STREAM,	0, 0,	daytime_stream,
    174 	"daytime",	SOCK_DGRAM,	0, 0,	daytime_dg,
    175 
    176 	/* Familiar character generator */
    177 	"chargen",	SOCK_STREAM,	1, 0,	chargen_stream,
    178 	"chargen",	SOCK_DGRAM,	0, 0,	chargen_dg,
    179 	0
    180 };
    181 
    182 #define NUMINT	(sizeof(intab) / sizeof(struct inent))
    183 char	*CONFIG = _PATH_INETDCONF;
    184 char	**Argv;
    185 char 	*LastArg;
    186 
    187 main(argc, argv, envp)
    188 	int argc;
    189 	char *argv[], *envp[];
    190 {
    191 	extern char *optarg;
    192 	extern int optind;
    193 	register struct servtab *sep;
    194 	register struct passwd *pwd;
    195 	register int tmpint;
    196 	struct sigvec sv;
    197 	int ch, pid, dofork;
    198 	char buf[50];
    199 
    200 	Argv = argv;
    201 	if (envp == 0 || *envp == 0)
    202 		envp = argv;
    203 	while (*envp)
    204 		envp++;
    205 	LastArg = envp[-1] + strlen(envp[-1]);
    206 
    207 	while ((ch = getopt(argc, argv, "d")) != EOF)
    208 		switch(ch) {
    209 		case 'd':
    210 			debug = 1;
    211 			options |= SO_DEBUG;
    212 			break;
    213 		case '?':
    214 		default:
    215 			fprintf(stderr, "usage: inetd [-d]");
    216 			exit(1);
    217 		}
    218 	argc -= optind;
    219 	argv += optind;
    220 
    221 	if (argc > 0)
    222 		CONFIG = argv[0];
    223 	if (debug == 0)
    224 		daemon(0, 0);
    225 	openlog("inetd", LOG_PID | LOG_NOWAIT, LOG_DAEMON);
    226 	bzero((char *)&sv, sizeof(sv));
    227 	sv.sv_mask = SIGBLOCK;
    228 	sv.sv_handler = retry;
    229 	sigvec(SIGALRM, &sv, (struct sigvec *)0);
    230 	config();
    231 	sv.sv_handler = config;
    232 	sigvec(SIGHUP, &sv, (struct sigvec *)0);
    233 	sv.sv_handler = reapchild;
    234 	sigvec(SIGCHLD, &sv, (struct sigvec *)0);
    235 
    236 	{
    237 		/* space for daemons to overwrite environment for ps */
    238 #define	DUMMYSIZE	100
    239 		char dummy[DUMMYSIZE];
    240 
    241 		(void)memset(dummy, 'x', sizeof(DUMMYSIZE) - 1);
    242 		dummy[DUMMYSIZE - 1] = '\0';
    243 		(void)setenv("inetd_dummy", dummy, 1);
    244 	}
    245 
    246 	for (;;) {
    247 	    int n, ctrl;
    248 	    fd_set readable;
    249 
    250 	    if (nsock == 0) {
    251 		(void) sigblock(SIGBLOCK);
    252 		while (nsock == 0)
    253 		    sigpause(0L);
    254 		(void) sigsetmask(0L);
    255 	    }
    256 	    readable = allsock;
    257 	    if ((n = select(maxsock + 1, &readable, (fd_set *)0,
    258 		(fd_set *)0, (struct timeval *)0)) <= 0) {
    259 		    if (n < 0 && errno != EINTR)
    260 			syslog(LOG_WARNING, "select: %m\n");
    261 		    sleep(1);
    262 		    continue;
    263 	    }
    264 	    for (sep = servtab; n && sep; sep = sep->se_next)
    265 	        if (sep->se_fd != -1 && FD_ISSET(sep->se_fd, &readable)) {
    266 		    n--;
    267 		    if (debug)
    268 			    fprintf(stderr, "someone wants %s\n",
    269 				sep->se_service);
    270 		    if (sep->se_socktype == SOCK_STREAM) {
    271 			    ctrl = accept(sep->se_fd, (struct sockaddr *)0,
    272 				(int *)0);
    273 			    if (debug)
    274 				    fprintf(stderr, "accept, ctrl %d\n", ctrl);
    275 			    if (ctrl < 0) {
    276 				    if (errno == EINTR)
    277 					    continue;
    278 				    syslog(LOG_WARNING, "accept (for %s): %m",
    279 					    sep->se_service);
    280 				    continue;
    281 			    }
    282 		    } else
    283 			    ctrl = sep->se_fd;
    284 		    (void) sigblock(SIGBLOCK);
    285 		    pid = 0;
    286 		    dofork = (sep->se_bi == 0 || sep->se_bi->bi_fork);
    287 		    if (dofork) {
    288 			    if (sep->se_count++ == 0)
    289 				(void)gettimeofday(&sep->se_time,
    290 				    (struct timezone *)0);
    291 			    else if (sep->se_count >= TOOMANY) {
    292 				struct timeval now;
    293 
    294 				(void)gettimeofday(&now, (struct timezone *)0);
    295 				if (now.tv_sec - sep->se_time.tv_sec >
    296 				    CNT_INTVL) {
    297 					sep->se_time = now;
    298 					sep->se_count = 1;
    299 				} else {
    300 					syslog(LOG_ERR,
    301 			"%s/%s server failing (looping), service terminated\n",
    302 					    sep->se_service, sep->se_proto);
    303 					FD_CLR(sep->se_fd, &allsock);
    304 					(void) close(sep->se_fd);
    305 					sep->se_fd = -1;
    306 					sep->se_count = 0;
    307 					nsock--;
    308 					if (!timingout) {
    309 						timingout = 1;
    310 						alarm(RETRYTIME);
    311 					}
    312 				}
    313 			    }
    314 			    pid = fork();
    315 		    }
    316 		    if (pid < 0) {
    317 			    syslog(LOG_ERR, "fork: %m");
    318 			    if (sep->se_socktype == SOCK_STREAM)
    319 				    close(ctrl);
    320 			    sigsetmask(0L);
    321 			    sleep(1);
    322 			    continue;
    323 		    }
    324 		    if (pid && sep->se_wait) {
    325 			    sep->se_wait = pid;
    326 			    if (sep->se_fd >= 0) {
    327 				FD_CLR(sep->se_fd, &allsock);
    328 			        nsock--;
    329 			    }
    330 		    }
    331 		    sigsetmask(0L);
    332 		    if (pid == 0) {
    333 			    if (debug && dofork)
    334 				setsid();
    335 			    if (dofork)
    336 				for (tmpint = maxsock; --tmpint > 2; )
    337 					if (tmpint != ctrl)
    338 						close(tmpint);
    339 			    if (sep->se_bi)
    340 				(*sep->se_bi->bi_fn)(ctrl, sep);
    341 			    else {
    342 				if (debug)
    343 					fprintf(stderr, "%d execl %s\n",
    344 					    getpid(), sep->se_server);
    345 				dup2(ctrl, 0);
    346 				close(ctrl);
    347 				dup2(0, 1);
    348 				dup2(0, 2);
    349 				if ((pwd = getpwnam(sep->se_user)) == NULL) {
    350 					syslog(LOG_ERR,
    351 					    "getpwnam: %s: No such user",
    352 					    sep->se_user);
    353 					if (sep->se_socktype != SOCK_STREAM)
    354 						recv(0, buf, sizeof (buf), 0);
    355 					_exit(1);
    356 				}
    357 				if (pwd->pw_uid) {
    358 					(void) setgid((gid_t)pwd->pw_gid);
    359 					initgroups(pwd->pw_name, pwd->pw_gid);
    360 					(void) setuid((uid_t)pwd->pw_uid);
    361 				}
    362 				execv(sep->se_server, sep->se_argv);
    363 				if (sep->se_socktype != SOCK_STREAM)
    364 					recv(0, buf, sizeof (buf), 0);
    365 				syslog(LOG_ERR, "execv %s: %m", sep->se_server);
    366 				_exit(1);
    367 			    }
    368 		    }
    369 		    if (sep->se_socktype == SOCK_STREAM)
    370 			    close(ctrl);
    371 		}
    372 	}
    373 }
    374 
    375 void
    376 reapchild()
    377 {
    378 	int status;
    379 	int pid;
    380 	register struct servtab *sep;
    381 
    382 	for (;;) {
    383 		pid = wait3(&status, WNOHANG, (struct rusage *)0);
    384 		if (pid <= 0)
    385 			break;
    386 		if (debug)
    387 			fprintf(stderr, "%d reaped\n", pid);
    388 		for (sep = servtab; sep; sep = sep->se_next)
    389 			if (sep->se_wait == pid) {
    390 				if (status)
    391 					syslog(LOG_WARNING,
    392 					    "%s: exit status 0x%x",
    393 					    sep->se_server, status);
    394 				if (debug)
    395 					fprintf(stderr, "restored %s, fd %d\n",
    396 					    sep->se_service, sep->se_fd);
    397 				FD_SET(sep->se_fd, &allsock);
    398 				nsock++;
    399 				sep->se_wait = 1;
    400 			}
    401 	}
    402 }
    403 
    404 void
    405 config()
    406 {
    407 	register struct servtab *sep, *cp, **sepp;
    408 	struct servtab *getconfigent(), *enter();
    409 	long omask;
    410 
    411 	if (!setconfig()) {
    412 		syslog(LOG_ERR, "%s: %m", CONFIG);
    413 		return;
    414 	}
    415 	for (sep = servtab; sep; sep = sep->se_next)
    416 		sep->se_checked = 0;
    417 	while (cp = getconfigent()) {
    418 		for (sep = servtab; sep; sep = sep->se_next)
    419 			if (strcmp(sep->se_service, cp->se_service) == 0 &&
    420 			    strcmp(sep->se_proto, cp->se_proto) == 0)
    421 				break;
    422 		if (sep != 0) {
    423 			int i;
    424 
    425 			omask = sigblock(SIGBLOCK);
    426 			/*
    427 			 * sep->se_wait may be holding the pid of a daemon
    428 			 * that we're waiting for.  If so, don't overwrite
    429 			 * it unless the config file explicitly says don't
    430 			 * wait.
    431 			 */
    432 			if (cp->se_bi == 0 &&
    433 			    (sep->se_wait == 1 || cp->se_wait == 0))
    434 				sep->se_wait = cp->se_wait;
    435 #define SWAP(a, b) { char *c = a; a = b; b = c; }
    436 			if (cp->se_user)
    437 				SWAP(sep->se_user, cp->se_user);
    438 			if (cp->se_server)
    439 				SWAP(sep->se_server, cp->se_server);
    440 			for (i = 0; i < MAXARGV; i++)
    441 				SWAP(sep->se_argv[i], cp->se_argv[i]);
    442 			sigsetmask(omask);
    443 			freeconfig(cp);
    444 			if (debug)
    445 				print_service("REDO", sep);
    446 		} else {
    447 			sep = enter(cp);
    448 			if (debug)
    449 				print_service("ADD ", sep);
    450 		}
    451 		sep->se_checked = 1;
    452                 if (!sep->se_rpc) {
    453                         sp = getservbyname(sep->se_service, sep->se_proto);
    454                         if (sp == 0) {
    455                                 syslog(LOG_ERR, "%s/%s: unknown service",
    456                                        sep->se_service, sep->se_proto);
    457                                 if (sep->se_fd != -1)
    458                                         (void) close(sep->se_fd);
    459                                 sep->se_fd = -1;
    460                                 continue;
    461                         }
    462                         if (sp->s_port != sep->se_ctrladdr.sin_port) {
    463                                 sep->se_ctrladdr.sin_port = sp->s_port;
    464                                 if (sep->se_fd != -1)
    465                                         (void) close(sep->se_fd);
    466                                 sep->se_fd = -1;
    467                         }
    468 		}
    469                 else {
    470                         rpc = getrpcbyname(sep->se_service);
    471                         if (rpc == 0) {
    472                                 syslog(LOG_ERR, "%s/%s unknown RPC service.",
    473                                        sep->se_service, sep->se_proto);
    474                                 if (sep->se_fd != -1)
    475                                         (void) close(sep->se_fd);
    476                                 sep->se_fd = -1;
    477                                 continue;
    478                         }
    479                         if (rpc->r_number != sep->se_rpc_prog) {
    480                                 if (sep->se_rpc_prog)
    481                                         unregisterrpc(sep);
    482                                 sep->se_rpc_prog = rpc->r_number;
    483                                 if (sep->se_fd != -1)
    484                                         (void) close(sep->se_fd);
    485                                 sep->se_fd = -1;
    486                         }
    487                 }
    488 
    489 		if (sep->se_fd == -1)
    490 			setup(sep);
    491 	}
    492 	endconfig();
    493 	/*
    494 	 * Purge anything not looked at above.
    495 	 */
    496 	omask = sigblock(SIGBLOCK);
    497 	sepp = &servtab;
    498 	while (sep = *sepp) {
    499 		if (sep->se_checked) {
    500 			sepp = &sep->se_next;
    501 			continue;
    502 		}
    503 		*sepp = sep->se_next;
    504 		if (sep->se_fd != -1) {
    505 			FD_CLR(sep->se_fd, &allsock);
    506 			nsock--;
    507 			(void) close(sep->se_fd);
    508 		}
    509 		if (debug)
    510 			print_service("FREE", sep);
    511                 if (sep->se_rpc && sep->se_rpc_prog > 0)
    512                         unregisterrpc(sep);
    513 		freeconfig(sep);
    514 		free((char *)sep);
    515 	}
    516 	(void) sigsetmask(omask);
    517 }
    518 
    519 void
    520 unregisterrpc(sep)
    521 	register struct servtab *sep;
    522 {
    523         int i;
    524         struct servtab *sepp;
    525 	long omask;
    526 
    527 	omask = sigblock(SIGBLOCK);
    528         for (sepp = servtab; sepp; sepp = sepp->se_next) {
    529                 if (sepp == sep)
    530                         continue;
    531 		if (sep->se_checked == 0 ||
    532                     !sepp->se_rpc ||
    533                     sep->se_rpc_prog != sepp->se_rpc_prog)
    534 			continue;
    535                 return;
    536         }
    537         if (debug)
    538                 print_service("UNREG", sep);
    539         for (i = sep->se_rpc_lowvers; i <= sep->se_rpc_highvers; i++)
    540                 pmap_unset(sep->se_rpc_prog, i);
    541         if (sep->se_fd != -1)
    542                 (void) close(sep->se_fd);
    543         sep->se_fd = -1;
    544 	(void) sigsetmask(omask);
    545 }
    546 
    547 void
    548 retry()
    549 {
    550 	register struct servtab *sep;
    551 
    552 	timingout = 0;
    553 	for (sep = servtab; sep; sep = sep->se_next)
    554 		if (sep->se_fd == -1)
    555 			setup(sep);
    556 }
    557 
    558 setup(sep)
    559 	register struct servtab *sep;
    560 {
    561 	int on = 1;
    562 
    563 	if ((sep->se_fd = socket(AF_INET, sep->se_socktype, 0)) < 0) {
    564 		syslog(LOG_ERR, "%s/%s: socket: %m",
    565 		    sep->se_service, sep->se_proto);
    566 		return;
    567 	}
    568 #define	turnon(fd, opt) \
    569 setsockopt(fd, SOL_SOCKET, opt, (char *)&on, sizeof (on))
    570 	if (strcmp(sep->se_proto, "tcp") == 0 && (options & SO_DEBUG) &&
    571 	    turnon(sep->se_fd, SO_DEBUG) < 0)
    572 		syslog(LOG_ERR, "setsockopt (SO_DEBUG): %m");
    573 	if (turnon(sep->se_fd, SO_REUSEADDR) < 0)
    574 		syslog(LOG_ERR, "setsockopt (SO_REUSEADDR): %m");
    575 #undef turnon
    576 	if (bind(sep->se_fd, (struct sockaddr *)&sep->se_ctrladdr,
    577 	    sizeof (sep->se_ctrladdr)) < 0) {
    578 		syslog(LOG_ERR, "%s/%s: bind: %m",
    579 		    sep->se_service, sep->se_proto);
    580 		(void) close(sep->se_fd);
    581 		sep->se_fd = -1;
    582 		if (!timingout) {
    583 			timingout = 1;
    584 			alarm(RETRYTIME);
    585 		}
    586 		return;
    587 	}
    588         if (sep->se_rpc) {
    589                 int i, len;
    590                 if (getsockname(sep->se_fd, (struct sockaddr *)&sep->se_ctrladdr,
    591                                 &len) < 0) {
    592                         syslog(LOG_ERR, "%s/%s: getsockname: %m",
    593                                sep->se_service, sep->se_proto);
    594                         (void) close(sep->se_fd);
    595                         sep->se_fd = -1;
    596                         return;
    597                 }
    598                 if (debug)
    599                         print_service("REG ", sep);
    600                 for (i = sep->se_rpc_lowvers; i <= sep->se_rpc_highvers; i++) {
    601                         pmap_unset(sep->se_rpc_prog, i);
    602                         pmap_set(sep->se_rpc_prog, i,
    603                                  (sep->se_socktype == SOCK_DGRAM)
    604                                  ? IPPROTO_UDP : IPPROTO_TCP,
    605                                  ntohs(sep->se_ctrladdr.sin_port));
    606                 }
    607 
    608         }
    609 	if (sep->se_socktype == SOCK_STREAM)
    610 		listen(sep->se_fd, 10);
    611 	FD_SET(sep->se_fd, &allsock);
    612 	nsock++;
    613 	if (sep->se_fd > maxsock)
    614 		maxsock = sep->se_fd;
    615 }
    616 
    617 struct servtab *
    618 enter(cp)
    619 	struct servtab *cp;
    620 {
    621 	register struct servtab *sep;
    622 	long omask;
    623 
    624 	sep = (struct servtab *)malloc(sizeof (*sep));
    625 	if (sep == (struct servtab *)0) {
    626 		syslog(LOG_ERR, "Out of memory.");
    627 		exit(-1);
    628 	}
    629 	*sep = *cp;
    630 	sep->se_fd = -1;
    631 	omask = sigblock(SIGBLOCK);
    632 	sep->se_next = servtab;
    633 	servtab = sep;
    634 	sigsetmask(omask);
    635 	return (sep);
    636 }
    637 
    638 FILE	*fconfig = NULL;
    639 struct	servtab serv;
    640 char	line[256];
    641 char	*skip(), *nextline();
    642 
    643 setconfig()
    644 {
    645 
    646 	if (fconfig != NULL) {
    647 		fseek(fconfig, 0L, L_SET);
    648 		return (1);
    649 	}
    650 	fconfig = fopen(CONFIG, "r");
    651 	return (fconfig != NULL);
    652 }
    653 
    654 endconfig()
    655 {
    656 	if (fconfig) {
    657 		(void) fclose(fconfig);
    658 		fconfig = NULL;
    659 	}
    660 }
    661 
    662 struct servtab *
    663 getconfigent()
    664 {
    665 	register struct servtab *sep = &serv;
    666 	int argc;
    667 	char *cp, *arg, *newstr();
    668         char *versp;
    669 
    670 more:
    671 	while ((cp = nextline(fconfig)) && *cp == '#')
    672 		;
    673 	if (cp == NULL)
    674 		return ((struct servtab *)0);
    675 	arg = skip(&cp);
    676 	if (arg == NULL)
    677 		goto more;
    678 	sep->se_service = newstr(arg);
    679 	arg = skip(&cp);
    680 	if (strcmp(arg, "stream") == 0)
    681 		sep->se_socktype = SOCK_STREAM;
    682 	else if (strcmp(arg, "dgram") == 0)
    683 		sep->se_socktype = SOCK_DGRAM;
    684 	else if (strcmp(arg, "rdm") == 0)
    685 		sep->se_socktype = SOCK_RDM;
    686 	else if (strcmp(arg, "seqpacket") == 0)
    687 		sep->se_socktype = SOCK_SEQPACKET;
    688 	else if (strcmp(arg, "raw") == 0)
    689 		sep->se_socktype = SOCK_RAW;
    690 	else
    691 		sep->se_socktype = -1;
    692 	sep->se_proto = newstr(skip(&cp));
    693         sep->se_rpc = 0;
    694         if (strncmp(sep->se_proto, "rpc/", 4) == 0) {
    695                 sep->se_proto += 4;
    696                 sep->se_rpc = 1;
    697                 sep->se_rpc_prog = sep->se_rpc_lowvers = sep->se_rpc_lowvers = 0;
    698                 sep->se_ctrladdr.sin_family = AF_INET;
    699                 sep->se_ctrladdr.sin_port = 0;
    700                 sep->se_ctrladdr.sin_addr.s_addr = htonl(INADDR_ANY);
    701                 if (versp = rindex(sep->se_service, '/')) {
    702                         *versp++ = '\0';
    703                         switch (sscanf(versp, "%d-%d",
    704                                        &sep->se_rpc_lowvers,
    705                                        &sep->se_rpc_highvers)) {
    706                         case 2:
    707                                 break;
    708                         case 1:
    709                                 sep->se_rpc_highvers =
    710                                         sep->se_rpc_lowvers;
    711                                 break;
    712                         default:
    713                                 syslog(LOG_ERR, "bad RPC version specifier; %s\n", sep->se_service);
    714                                 freeconfig(sep);
    715                                 goto more;
    716                         }
    717                 }
    718                 else {
    719                         sep->se_rpc_lowvers =
    720                                 sep->se_rpc_highvers = 1;
    721                 }
    722         }
    723 	arg = skip(&cp);
    724 	sep->se_wait = strcmp(arg, "wait") == 0;
    725 	sep->se_user = newstr(skip(&cp));
    726 	sep->se_server = newstr(skip(&cp));
    727 	if (strcmp(sep->se_server, "internal") == 0) {
    728 		register struct biltin *bi;
    729 
    730 		for (bi = biltins; bi->bi_service; bi++)
    731 			if (bi->bi_socktype == sep->se_socktype &&
    732 			    strcmp(bi->bi_service, sep->se_service) == 0)
    733 				break;
    734 		if (bi->bi_service == 0) {
    735 			syslog(LOG_ERR, "internal service %s unknown\n",
    736 				sep->se_service);
    737 			goto more;
    738 		}
    739 		sep->se_bi = bi;
    740 		sep->se_wait = bi->bi_wait;
    741 	} else
    742 		sep->se_bi = NULL;
    743 	argc = 0;
    744 	for (arg = skip(&cp); cp; arg = skip(&cp))
    745 		if (argc < MAXARGV)
    746 			sep->se_argv[argc++] = newstr(arg);
    747 	while (argc <= MAXARGV)
    748 		sep->se_argv[argc++] = NULL;
    749 	return (sep);
    750 }
    751 
    752 freeconfig(cp)
    753 	register struct servtab *cp;
    754 {
    755 	int i;
    756 
    757 	if (cp->se_service)
    758 		free(cp->se_service);
    759 	if (cp->se_proto)
    760 		free(cp->se_proto);
    761 	if (cp->se_user)
    762 		free(cp->se_user);
    763 	if (cp->se_server)
    764 		free(cp->se_server);
    765 	for (i = 0; i < MAXARGV; i++)
    766 		if (cp->se_argv[i])
    767 			free(cp->se_argv[i]);
    768 }
    769 
    770 char *
    771 skip(cpp)
    772 	char **cpp;
    773 {
    774 	register char *cp = *cpp;
    775 	char *start;
    776 
    777 again:
    778 	while (*cp == ' ' || *cp == '\t')
    779 		cp++;
    780 	if (*cp == '\0') {
    781 		int c;
    782 
    783 		c = getc(fconfig);
    784 		(void) ungetc(c, fconfig);
    785 		if (c == ' ' || c == '\t')
    786 			if (cp = nextline(fconfig))
    787 				goto again;
    788 		*cpp = (char *)0;
    789 		return ((char *)0);
    790 	}
    791 	start = cp;
    792 	while (*cp && *cp != ' ' && *cp != '\t')
    793 		cp++;
    794 	if (*cp != '\0')
    795 		*cp++ = '\0';
    796 	*cpp = cp;
    797 	return (start);
    798 }
    799 
    800 char *
    801 nextline(fd)
    802 	FILE *fd;
    803 {
    804 	char *cp;
    805 
    806 	if (fgets(line, sizeof (line), fd) == NULL)
    807 		return ((char *)0);
    808 	cp = index(line, '\n');
    809 	if (cp)
    810 		*cp = '\0';
    811 	return (line);
    812 }
    813 
    814 char *
    815 newstr(cp)
    816 	char *cp;
    817 {
    818 	if (cp = strdup(cp ? cp : ""))
    819 		return(cp);
    820 	syslog(LOG_ERR, "strdup: %m");
    821 	exit(-1);
    822 }
    823 
    824 setproctitle(a, s)
    825 	char *a;
    826 	int s;
    827 {
    828 	int size;
    829 	register char *cp;
    830 	struct sockaddr_in sin;
    831 	char buf[80];
    832 
    833 	cp = Argv[0];
    834 	size = sizeof(sin);
    835 	if (getpeername(s, (struct sockaddr *)&sin, &size) == 0)
    836 		(void) sprintf(buf, "-%s [%s]", a, inet_ntoa(sin.sin_addr));
    837 	else
    838 		(void) sprintf(buf, "-%s", a);
    839 	strncpy(cp, buf, LastArg - cp);
    840 	cp += strlen(cp);
    841 	while (cp < LastArg)
    842 		*cp++ = ' ';
    843 }
    844 
    845 /*
    846  * Internet services provided internally by inetd:
    847  */
    848 #define	BUFSIZE	8192
    849 
    850 /* ARGSUSED */
    851 echo_stream(s, sep)		/* Echo service -- echo data back */
    852 	int s;
    853 	struct servtab *sep;
    854 {
    855 	char buffer[BUFSIZE];
    856 	int i;
    857 
    858 	setproctitle(sep->se_service, s);
    859 	while ((i = read(s, buffer, sizeof(buffer))) > 0 &&
    860 	    write(s, buffer, i) > 0)
    861 		;
    862 	exit(0);
    863 }
    864 
    865 /* ARGSUSED */
    866 echo_dg(s, sep)			/* Echo service -- echo data back */
    867 	int s;
    868 	struct servtab *sep;
    869 {
    870 	char buffer[BUFSIZE];
    871 	int i, size;
    872 	struct sockaddr sa;
    873 
    874 	size = sizeof(sa);
    875 	if ((i = recvfrom(s, buffer, sizeof(buffer), 0, &sa, &size)) < 0)
    876 		return;
    877 	(void) sendto(s, buffer, i, 0, &sa, sizeof(sa));
    878 }
    879 
    880 /* ARGSUSED */
    881 discard_stream(s, sep)		/* Discard service -- ignore data */
    882 	int s;
    883 	struct servtab *sep;
    884 {
    885 	int ret;
    886 	char buffer[BUFSIZE];
    887 
    888 	setproctitle(sep->se_service, s);
    889 	while (1) {
    890 		while ((ret = read(s, buffer, sizeof(buffer))) > 0)
    891 			;
    892 		if (ret == 0 || errno != EINTR)
    893 			break;
    894 	}
    895 	exit(0);
    896 }
    897 
    898 /* ARGSUSED */
    899 discard_dg(s, sep)		/* Discard service -- ignore data */
    900 	int s;
    901 	struct servtab *sep;
    902 {
    903 	char buffer[BUFSIZE];
    904 
    905 	(void) read(s, buffer, sizeof(buffer));
    906 }
    907 
    908 #include <ctype.h>
    909 #define LINESIZ 72
    910 char ring[128];
    911 char *endring;
    912 
    913 initring()
    914 {
    915 	register int i;
    916 
    917 	endring = ring;
    918 
    919 	for (i = 0; i <= 128; ++i)
    920 		if (isprint(i))
    921 			*endring++ = i;
    922 }
    923 
    924 /* ARGSUSED */
    925 chargen_stream(s, sep)		/* Character generator */
    926 	int s;
    927 	struct servtab *sep;
    928 {
    929 	register char *rs;
    930 	int len;
    931 	char text[LINESIZ+2];
    932 
    933 	setproctitle(sep->se_service, s);
    934 
    935 	if (!endring) {
    936 		initring();
    937 		rs = ring;
    938 	}
    939 
    940 	text[LINESIZ] = '\r';
    941 	text[LINESIZ + 1] = '\n';
    942 	for (rs = ring;;) {
    943 		if ((len = endring - rs) >= LINESIZ)
    944 			bcopy(rs, text, LINESIZ);
    945 		else {
    946 			bcopy(rs, text, len);
    947 			bcopy(ring, text + len, LINESIZ - len);
    948 		}
    949 		if (++rs == endring)
    950 			rs = ring;
    951 		if (write(s, text, sizeof(text)) != sizeof(text))
    952 			break;
    953 	}
    954 	exit(0);
    955 }
    956 
    957 /* ARGSUSED */
    958 chargen_dg(s, sep)		/* Character generator */
    959 	int s;
    960 	struct servtab *sep;
    961 {
    962 	struct sockaddr sa;
    963 	static char *rs;
    964 	int len, size;
    965 	char text[LINESIZ+2];
    966 
    967 	if (endring == 0) {
    968 		initring();
    969 		rs = ring;
    970 	}
    971 
    972 	size = sizeof(sa);
    973 	if (recvfrom(s, text, sizeof(text), 0, &sa, &size) < 0)
    974 		return;
    975 
    976 	if ((len = endring - rs) >= LINESIZ)
    977 		bcopy(rs, text, LINESIZ);
    978 	else {
    979 		bcopy(rs, text, len);
    980 		bcopy(ring, text + len, LINESIZ - len);
    981 	}
    982 	if (++rs == endring)
    983 		rs = ring;
    984 	text[LINESIZ] = '\r';
    985 	text[LINESIZ + 1] = '\n';
    986 	(void) sendto(s, text, sizeof(text), 0, &sa, sizeof(sa));
    987 }
    988 
    989 /*
    990  * Return a machine readable date and time, in the form of the
    991  * number of seconds since midnight, Jan 1, 1900.  Since gettimeofday
    992  * returns the number of seconds since midnight, Jan 1, 1970,
    993  * we must add 2208988800 seconds to this figure to make up for
    994  * some seventy years Bell Labs was asleep.
    995  */
    996 
    997 long
    998 machtime()
    999 {
   1000 	struct timeval tv;
   1001 
   1002 	if (gettimeofday(&tv, (struct timezone *)0) < 0) {
   1003 		fprintf(stderr, "Unable to get time of day\n");
   1004 		return (0L);
   1005 	}
   1006 	return (htonl((long)tv.tv_sec + 2208988800));
   1007 }
   1008 
   1009 /* ARGSUSED */
   1010 machtime_stream(s, sep)
   1011 	int s;
   1012 	struct servtab *sep;
   1013 {
   1014 	long result;
   1015 
   1016 	result = machtime();
   1017 	(void) write(s, (char *) &result, sizeof(result));
   1018 }
   1019 
   1020 /* ARGSUSED */
   1021 machtime_dg(s, sep)
   1022 	int s;
   1023 	struct servtab *sep;
   1024 {
   1025 	long result;
   1026 	struct sockaddr sa;
   1027 	int size;
   1028 
   1029 	size = sizeof(sa);
   1030 	if (recvfrom(s, (char *)&result, sizeof(result), 0, &sa, &size) < 0)
   1031 		return;
   1032 	result = machtime();
   1033 	(void) sendto(s, (char *) &result, sizeof(result), 0, &sa, sizeof(sa));
   1034 }
   1035 
   1036 /* ARGSUSED */
   1037 daytime_stream(s, sep)		/* Return human-readable time of day */
   1038 	int s;
   1039 	struct servtab *sep;
   1040 {
   1041 	char buffer[256];
   1042 	time_t time(), clock;
   1043 	char *ctime();
   1044 
   1045 	clock = time((time_t *) 0);
   1046 
   1047 	(void) sprintf(buffer, "%.24s\r\n", ctime(&clock));
   1048 	(void) write(s, buffer, strlen(buffer));
   1049 }
   1050 
   1051 /* ARGSUSED */
   1052 daytime_dg(s, sep)		/* Return human-readable time of day */
   1053 	int s;
   1054 	struct servtab *sep;
   1055 {
   1056 	char buffer[256];
   1057 	time_t time(), clock;
   1058 	struct sockaddr sa;
   1059 	int size;
   1060 	char *ctime();
   1061 
   1062 	clock = time((time_t *) 0);
   1063 
   1064 	size = sizeof(sa);
   1065 	if (recvfrom(s, buffer, sizeof(buffer), 0, &sa, &size) < 0)
   1066 		return;
   1067 	(void) sprintf(buffer, "%.24s\r\n", ctime(&clock));
   1068 	(void) sendto(s, buffer, strlen(buffer), 0, &sa, sizeof(sa));
   1069 }
   1070 
   1071 /*
   1072  * print_service:
   1073  *	Dump relevant information to stderr
   1074  */
   1075 print_service(action, sep)
   1076 	char *action;
   1077 	struct servtab *sep;
   1078 {
   1079         if (sep->se_rpc)
   1080                 fprintf(stderr,
   1081                         "%s: %s rpcnum=%d, rpcvers=%d/%d, wait=%d, user=%s builtin=%x server=%s\n",
   1082                         action, sep->se_service,
   1083                         sep->se_rpc_prog, sep->se_rpc_lowvers, sep->se_rpc_highvers,
   1084                         sep->se_wait, sep->se_user, (int)sep->se_bi, sep->se_server);
   1085         else
   1086                 fprintf(stderr,
   1087                         "%s: %s proto=%s, wait=%d, user=%s builtin=%x server=%s\n",
   1088                         action, sep->se_service, sep->se_proto,
   1089                         sep->se_wait, sep->se_user, (int)sep->se_bi, sep->se_server);
   1090 }
   1091