inetd.c revision 1.46 1 /* $NetBSD: inetd.c,v 1.46 1999/01/20 09:24:06 mycroft Exp $ */
2
3 /*-
4 * Copyright (c) 1998 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
9 * NASA Ames Research Center.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 * 3. All advertising materials mentioning features or use of this software
20 * must display the following acknowledgement:
21 * This product includes software developed by the NetBSD
22 * Foundation, Inc. and its contributors.
23 * 4. Neither the name of The NetBSD Foundation nor the names of its
24 * contributors may be used to endorse or promote products derived
25 * from this software without specific prior written permission.
26 *
27 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
28 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
29 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
30 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
31 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
32 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
33 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
34 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
35 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
36 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
37 * POSSIBILITY OF SUCH DAMAGE.
38 */
39
40 /*
41 * Copyright (c) 1983, 1991, 1993, 1994
42 * The Regents of the University of California. All rights reserved.
43 *
44 * Redistribution and use in source and binary forms, with or without
45 * modification, are permitted provided that the following conditions
46 * are met:
47 * 1. Redistributions of source code must retain the above copyright
48 * notice, this list of conditions and the following disclaimer.
49 * 2. Redistributions in binary form must reproduce the above copyright
50 * notice, this list of conditions and the following disclaimer in the
51 * documentation and/or other materials provided with the distribution.
52 * 3. All advertising materials mentioning features or use of this software
53 * must display the following acknowledgement:
54 * This product includes software developed by the University of
55 * California, Berkeley and its contributors.
56 * 4. Neither the name of the University nor the names of its contributors
57 * may be used to endorse or promote products derived from this software
58 * without specific prior written permission.
59 *
60 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
61 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
62 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
63 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
64 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
65 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
66 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
67 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
68 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
69 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
70 * SUCH DAMAGE.
71 */
72
73 #include <sys/cdefs.h>
74 #ifndef lint
75 __COPYRIGHT("@(#) Copyright (c) 1983, 1991, 1993, 1994\n\
76 The Regents of the University of California. All rights reserved.\n");
77 #if 0
78 static char sccsid[] = "@(#)inetd.c 8.4 (Berkeley) 4/13/94";
79 #else
80 __RCSID("$NetBSD: inetd.c,v 1.46 1999/01/20 09:24:06 mycroft Exp $");
81 #endif
82 #endif /* not lint */
83
84 /*
85 * Inetd - Internet super-server
86 *
87 * This program invokes all internet services as needed. Connection-oriented
88 * services are invoked each time a connection is made, by creating a process.
89 * This process is passed the connection as file descriptor 0 and is expected
90 * to do a getpeername to find out the source host and port.
91 *
92 * Datagram oriented services are invoked when a datagram
93 * arrives; a process is created and passed a pending message
94 * on file descriptor 0. Datagram servers may either connect
95 * to their peer, freeing up the original socket for inetd
96 * to receive further messages on, or ``take over the socket'',
97 * processing all arriving datagrams and, eventually, timing
98 * out. The first type of server is said to be ``multi-threaded'';
99 * the second type of server ``single-threaded''.
100 *
101 * Inetd uses a configuration file which is read at startup
102 * and, possibly, at some later time in response to a hangup signal.
103 * The configuration file is ``free format'' with fields given in the
104 * order shown below. Continuation lines for an entry must being with
105 * a space or tab. All fields must be present in each entry.
106 *
107 * service name must be in /etc/services or must
108 * name a tcpmux service
109 * socket type stream/dgram/raw/rdm/seqpacket
110 * protocol must be in /etc/protocols
111 * wait/nowait[.max] single-threaded/multi-threaded, max #
112 * user[.group] user/group to run daemon as
113 * server program full path name
114 * server program arguments maximum of MAXARGS (20)
115 *
116 * For RPC services
117 * service name/version must be in /etc/rpc
118 * socket type stream/dgram/raw/rdm/seqpacket
119 * protocol must be in /etc/protocols
120 * wait/nowait[.max] single-threaded/multi-threaded
121 * user[.group] user to run daemon as
122 * server program full path name
123 * server program arguments maximum of MAXARGS (20)
124 *
125 * For non-RPC services, the "service name" can be of the form
126 * hostaddress:servicename, in which case the hostaddress is used
127 * as the host portion of the address to listen on. If hostaddress
128 * consists of a single `*' character, INADDR_ANY is used.
129 *
130 * A line can also consist of just
131 * hostaddress:
132 * where hostaddress is as in the preceding paragraph. Such a line must
133 * have no further fields; the specified hostaddress is remembered and
134 * used for all further lines that have no hostaddress specified,
135 * until the next such line (or EOF). (This is why * is provided to
136 * allow explicit specification of INADDR_ANY.) A line
137 * *:
138 * is implicitly in effect at the beginning of the file.
139 *
140 * The hostaddress specifier may (and often will) contain dots;
141 * the service name must not.
142 *
143 * For RPC services, host-address specifiers are accepted and will
144 * work to some extent; however, because of limitations in the
145 * portmapper interface, it will not work to try to give more than
146 * one line for any given RPC service, even if the host-address
147 * specifiers are different.
148 *
149 * TCP services without official port numbers are handled with the
150 * RFC1078-based tcpmux internal service. Tcpmux listens on port 1 for
151 * requests. When a connection is made from a foreign host, the service
152 * requested is passed to tcpmux, which looks it up in the servtab list
153 * and returns the proper entry for the service. Tcpmux returns a
154 * negative reply if the service doesn't exist, otherwise the invoked
155 * server is expected to return the positive reply if the service type in
156 * inetd.conf file has the prefix "tcpmux/". If the service type has the
157 * prefix "tcpmux/+", tcpmux will return the positive reply for the
158 * process; this is for compatibility with older server code, and also
159 * allows you to invoke programs that use stdin/stdout without putting any
160 * special server code in them. Services that use tcpmux are "nowait"
161 * because they do not have a well-known port and hence cannot listen
162 * for new requests.
163 *
164 * Comment lines are indicated by a `#' in column 1.
165 */
166
167 /*
168 * Here's the scoop concerning the user.group feature:
169 *
170 * 1) set-group-option off.
171 *
172 * a) user = root: NO setuid() or setgid() is done
173 *
174 * b) other: setuid()
175 * setgid(primary group as found in passwd)
176 * initgroups(name, primary group)
177 *
178 * 2) set-group-option on.
179 *
180 * a) user = root: NO setuid()
181 * setgid(specified group)
182 * NO initgroups()
183 *
184 * b) other: setuid()
185 * setgid(specified group)
186 * initgroups(name, specified group)
187 *
188 */
189
190 #include <sys/param.h>
191 #include <sys/stat.h>
192 #include <sys/ioctl.h>
193 #include <sys/socket.h>
194 #include <sys/un.h>
195 #include <sys/wait.h>
196 #include <sys/time.h>
197 #include <sys/resource.h>
198
199 #ifndef RLIMIT_NOFILE
200 #define RLIMIT_NOFILE RLIMIT_OFILE
201 #endif
202
203 #define RPC
204
205 #include <netinet/in.h>
206 #include <arpa/inet.h>
207 #ifdef RPC
208 #include <rpc/rpc.h>
209 #include <rpc/pmap_clnt.h>
210 #endif
211
212 #include <ctype.h>
213 #include <errno.h>
214 #include <fcntl.h>
215 #include <grp.h>
216 #include <netdb.h>
217 #include <pwd.h>
218 #include <signal.h>
219 #include <stdio.h>
220 #include <stdlib.h>
221 #include <string.h>
222 #include <syslog.h>
223 #include <unistd.h>
224
225 #include "pathnames.h"
226
227 #ifdef LIBWRAP
228 # include <tcpd.h>
229 #ifndef LIBWRAP_ALLOW_FACILITY
230 # define LIBWRAP_ALLOW_FACILITY LOG_AUTH
231 #endif
232 #ifndef LIBWRAP_ALLOW_SEVERITY
233 # define LIBWRAP_ALLOW_SEVERITY LOG_INFO
234 #endif
235 #ifndef LIBWRAP_DENY_FACILITY
236 # define LIBWRAP_DENY_FACILITY LOG_AUTH
237 #endif
238 #ifndef LIBWRAP_DENY_SEVERITY
239 # define LIBWRAP_DENY_SEVERITY LOG_WARNING
240 #endif
241 int allow_severity = LIBWRAP_ALLOW_FACILITY|LIBWRAP_ALLOW_SEVERITY;
242 int deny_severity = LIBWRAP_DENY_FACILITY|LIBWRAP_DENY_SEVERITY;
243 #endif
244
245 #define TOOMANY 40 /* don't start more than TOOMANY */
246 #define CNT_INTVL 60 /* servers in CNT_INTVL sec. */
247 #define RETRYTIME (60*10) /* retry after bind or server fail */
248
249 #define SIGBLOCK (sigmask(SIGCHLD)|sigmask(SIGHUP)|sigmask(SIGALRM))
250
251 int debug;
252 #ifdef LIBWRAP
253 int lflag;
254 #endif
255 int nsock, maxsock;
256 fd_set allsock;
257 int options;
258 int timingout;
259 struct servent *sp;
260 char *curdom;
261
262 #ifndef OPEN_MAX
263 #define OPEN_MAX 64
264 #endif
265
266 /* Reserve some descriptors, 3 stdio + at least: 1 log, 1 conf. file */
267 #define FD_MARGIN (8)
268 typeof(((struct rlimit *)0)->rlim_cur) rlim_ofile_cur = OPEN_MAX;
269
270 #ifdef RLIMIT_NOFILE
271 struct rlimit rlim_ofile;
272 #endif
273
274 struct servtab {
275 char *se_hostaddr; /* host address to listen on */
276 char *se_service; /* name of service */
277 int se_socktype; /* type of socket to use */
278 int se_family; /* address family */
279 char *se_proto; /* protocol used */
280 int se_sndbuf; /* sndbuf size */
281 int se_rcvbuf; /* rcvbuf size */
282 int se_rpcprog; /* rpc program number */
283 int se_rpcversl; /* rpc program lowest version */
284 int se_rpcversh; /* rpc program highest version */
285 #define isrpcservice(sep) ((sep)->se_rpcversl != 0)
286 short se_wait; /* single threaded server */
287 short se_checked; /* looked at during merge */
288 char *se_user; /* user name to run as */
289 char *se_group; /* group name to run as */
290 struct biltin *se_bi; /* if built-in, description */
291 char *se_server; /* server program */
292 #define MAXARGV 20
293 char *se_argv[MAXARGV+1]; /* program arguments */
294 int se_fd; /* open descriptor */
295 int se_type; /* type */
296 union {
297 struct sockaddr se_un_ctrladdr;
298 struct sockaddr_in se_un_ctrladdr_in;
299 struct sockaddr_un se_un_ctrladdr_un;
300 } se_un; /* bound address */
301 #define se_ctrladdr se_un.se_un_ctrladdr
302 #define se_ctrladdr_in se_un.se_un_ctrladdr_in
303 #define se_ctrladdr_un se_un.se_un_ctrladdr_un
304 int se_ctrladdr_size;
305 int se_max; /* max # of instances of this service */
306 int se_count; /* number started since se_time */
307 struct timeval se_time; /* start of se_count */
308 #ifdef MULOG
309 int se_log;
310 #define MULOG_RFC931 0x40000000
311 #endif
312 struct servtab *se_next;
313 } *servtab;
314
315 #define NORM_TYPE 0
316 #define MUX_TYPE 1
317 #define MUXPLUS_TYPE 2
318 #define ISMUX(sep) (((sep)->se_type == MUX_TYPE) || \
319 ((sep)->se_type == MUXPLUS_TYPE))
320 #define ISMUXPLUS(sep) ((sep)->se_type == MUXPLUS_TYPE)
321
322
323 void chargen_dg __P((int, struct servtab *));
324 void chargen_stream __P((int, struct servtab *));
325 void close_sep __P((struct servtab *));
326 void config __P((int));
327 void daytime_dg __P((int, struct servtab *));
328 void daytime_stream __P((int, struct servtab *));
329 void discard_dg __P((int, struct servtab *));
330 void discard_stream __P((int, struct servtab *));
331 void echo_dg __P((int, struct servtab *));
332 void echo_stream __P((int, struct servtab *));
333 void endconfig __P((void));
334 struct servtab *enter __P((struct servtab *));
335 void freeconfig __P((struct servtab *));
336 struct servtab *getconfigent __P((void));
337 void goaway __P((int));
338 void machtime_dg __P((int, struct servtab *));
339 void machtime_stream __P((int, struct servtab *));
340 char *newstr __P((char *));
341 char *nextline __P((FILE *));
342 void print_service __P((char *, struct servtab *));
343 void reapchild __P((int));
344 void retry __P((int));
345 void run_service __P((int, struct servtab *));
346 int setconfig __P((void));
347 void setup __P((struct servtab *));
348 char *sskip __P((char **));
349 char *skip __P((char **));
350 void tcpmux __P((int, struct servtab *));
351 void usage __P((void));
352 void logpid __P((void));
353 void register_rpc __P((struct servtab *sep));
354 void unregister_rpc __P((struct servtab *sep));
355 void bump_nofile __P((void));
356 void inetd_setproctitle __P((char *, int));
357 void initring __P((void));
358 long machtime __P((void));
359 static int getline __P((int, char *, int));
360 int main __P((int, char *[], char *[]));
361
362 struct biltin {
363 char *bi_service; /* internally provided service name */
364 int bi_socktype; /* type of socket supported */
365 short bi_fork; /* 1 if should fork before call */
366 short bi_wait; /* 1 if should wait for child */
367 void (*bi_fn) __P((int, struct servtab *));
368 /* function which performs it */
369 } biltins[] = {
370 /* Echo received data */
371 { "echo", SOCK_STREAM, 1, 0, echo_stream },
372 { "echo", SOCK_DGRAM, 0, 0, echo_dg },
373
374 /* Internet /dev/null */
375 { "discard", SOCK_STREAM, 1, 0, discard_stream },
376 { "discard", SOCK_DGRAM, 0, 0, discard_dg },
377
378 /* Return 32 bit time since 1970 */
379 { "time", SOCK_STREAM, 0, 0, machtime_stream },
380 { "time", SOCK_DGRAM, 0, 0, machtime_dg },
381
382 /* Return human-readable time */
383 { "daytime", SOCK_STREAM, 0, 0, daytime_stream },
384 { "daytime", SOCK_DGRAM, 0, 0, daytime_dg },
385
386 /* Familiar character generator */
387 { "chargen", SOCK_STREAM, 1, 0, chargen_stream },
388 { "chargen", SOCK_DGRAM, 0, 0, chargen_dg },
389
390 { "tcpmux", SOCK_STREAM, 1, 0, tcpmux },
391
392 { NULL }
393 };
394
395 #define NUMINT (sizeof(intab) / sizeof(struct inent))
396 char *CONFIG = _PATH_INETDCONF;
397 char **Argv;
398 char *LastArg;
399 extern char *__progname;
400
401 #ifdef sun
402 /*
403 * Sun's RPC library caches the result of `dtablesize()'
404 * This is incompatible with our "bumping" of file descriptors "on demand"
405 */
406 int
407 _rpc_dtablesize()
408 {
409 return rlim_ofile_cur;
410 }
411 #endif
412
413 int
414 main(argc, argv, envp)
415 int argc;
416 char *argv[], *envp[];
417 {
418 struct servtab *sep, *nsep;
419 struct sigvec sv;
420 int ch, dofork;
421 pid_t pid;
422
423 Argv = argv;
424 if (envp == 0 || *envp == 0)
425 envp = argv;
426 while (*envp)
427 envp++;
428 LastArg = envp[-1] + strlen(envp[-1]);
429
430 while ((ch = getopt(argc, argv,
431 #ifdef LIBWRAP
432 "dl"
433 #else
434 "d"
435 #endif
436 )) != -1)
437 switch(ch) {
438 case 'd':
439 debug = 1;
440 options |= SO_DEBUG;
441 break;
442 #ifdef LIBWRAP
443 case 'l':
444 lflag = 1;
445 break;
446 #endif
447 case '?':
448 default:
449 usage();
450 }
451 argc -= optind;
452 argv += optind;
453
454 if (argc > 0)
455 CONFIG = argv[0];
456
457 if (debug == 0)
458 daemon(0, 0);
459 openlog(__progname, LOG_PID | LOG_NOWAIT, LOG_DAEMON);
460 logpid();
461
462 #ifdef RLIMIT_NOFILE
463 if (getrlimit(RLIMIT_NOFILE, &rlim_ofile) < 0) {
464 syslog(LOG_ERR, "getrlimit: %m");
465 } else {
466 rlim_ofile_cur = rlim_ofile.rlim_cur;
467 if (rlim_ofile_cur == RLIM_INFINITY) /* ! */
468 rlim_ofile_cur = OPEN_MAX;
469 }
470 #endif
471
472 memset(&sv, 0, sizeof(sv));
473 sv.sv_mask = SIGBLOCK;
474 sv.sv_handler = retry;
475 sigvec(SIGALRM, &sv, (struct sigvec *)0);
476 config(SIGHUP);
477 sv.sv_handler = config;
478 sigvec(SIGHUP, &sv, (struct sigvec *)0);
479 sv.sv_handler = reapchild;
480 sigvec(SIGCHLD, &sv, (struct sigvec *)0);
481 sv.sv_handler = goaway;
482 sigvec(SIGTERM, &sv, (struct sigvec *)0);
483 sv.sv_handler = goaway;
484 sigvec(SIGINT, &sv, (struct sigvec *)0);
485 sv.sv_mask = 0L;
486 sv.sv_handler = SIG_IGN;
487 sigvec(SIGPIPE, &sv, (struct sigvec *)0);
488
489 {
490 /* space for daemons to overwrite environment for ps */
491 #define DUMMYSIZE 100
492 char dummy[DUMMYSIZE];
493
494 (void)memset(dummy, 'x', DUMMYSIZE - 1);
495 dummy[DUMMYSIZE - 1] = '\0';
496
497 (void)setenv("inetd_dummy", dummy, 1);
498 }
499
500 for (;;) {
501 int n, ctrl;
502 fd_set readable;
503
504 if (nsock == 0) {
505 (void) sigblock(SIGBLOCK);
506 while (nsock == 0)
507 sigpause(0L);
508 (void) sigsetmask(0L);
509 }
510 readable = allsock;
511 if ((n = select(maxsock + 1, &readable, (fd_set *)0,
512 (fd_set *)0, (struct timeval *)0)) <= 0) {
513 if (n == -1 && errno != EINTR) {
514 syslog(LOG_WARNING, "select: %m");
515 sleep(1);
516 }
517 continue;
518 }
519 for (sep = servtab; n && sep; sep = nsep) {
520 nsep = sep->se_next;
521 if (sep->se_fd != -1 && FD_ISSET(sep->se_fd, &readable)) {
522 n--;
523 if (debug)
524 fprintf(stderr, "someone wants %s\n", sep->se_service);
525 if (!sep->se_wait && sep->se_socktype == SOCK_STREAM) {
526 /* XXX here do the libwrap check-before-accept */
527 ctrl = accept(sep->se_fd, (struct sockaddr *)0,
528 (int *)0);
529 if (debug)
530 fprintf(stderr, "accept, ctrl %d\n", ctrl);
531 if (ctrl < 0) {
532 if (errno != EINTR)
533 syslog(LOG_WARNING,
534 "accept (for %s): %m",
535 sep->se_service);
536 continue;
537 }
538 } else
539 ctrl = sep->se_fd;
540 (void) sigblock(SIGBLOCK);
541 pid = 0;
542 #ifdef LIBWRAP_INTERNAL
543 dofork = 1;
544 #else
545 dofork = (sep->se_bi == 0 || sep->se_bi->bi_fork);
546 #endif
547 if (dofork) {
548 if (sep->se_count++ == 0)
549 (void)gettimeofday(&sep->se_time,
550 (struct timezone *)0);
551 else if (sep->se_count >= sep->se_max) {
552 struct timeval now;
553
554 (void)gettimeofday(&now, (struct timezone *)0);
555 if (now.tv_sec - sep->se_time.tv_sec >
556 CNT_INTVL) {
557 sep->se_time = now;
558 sep->se_count = 1;
559 } else {
560 syslog(LOG_ERR,
561 "%s/%s server failing (looping), service terminated\n",
562 sep->se_service, sep->se_proto);
563 if (!sep->se_wait && sep->se_socktype == SOCK_STREAM)
564 close(ctrl);
565 close_sep(sep);
566 sigsetmask(0L);
567 if (!timingout) {
568 timingout = 1;
569 alarm(RETRYTIME);
570 }
571 continue;
572 }
573 }
574 pid = fork();
575 if (pid < 0) {
576 syslog(LOG_ERR, "fork: %m");
577 if (!sep->se_wait && sep->se_socktype == SOCK_STREAM)
578 close(ctrl);
579 sigsetmask(0L);
580 sleep(1);
581 continue;
582 }
583 if (pid != 0 && sep->se_wait) {
584 sep->se_wait = pid;
585 FD_CLR(sep->se_fd, &allsock);
586 nsock--;
587 }
588 if (pid == 0) {
589 sv.sv_mask = 0L;
590 sv.sv_handler = SIG_DFL;
591 sigvec(SIGPIPE, &sv, (struct sigvec *)0);
592 if (debug)
593 setsid();
594 }
595 }
596 sigsetmask(0L);
597 if (pid == 0) {
598 run_service(ctrl, sep);
599 if (dofork)
600 exit(0);
601 }
602 if (!sep->se_wait && sep->se_socktype == SOCK_STREAM)
603 close(ctrl);
604 }
605 }
606 }
607 }
608
609 void
610 run_service(ctrl, sep)
611 int ctrl;
612 struct servtab *sep;
613 {
614 struct passwd *pwd;
615 struct group *grp = NULL; /* XXX gcc */
616 char buf[7];
617 #ifdef LIBWRAP
618 struct request_info req;
619 int denied;
620 char *service = NULL; /* XXX gcc */
621 #endif
622
623 #ifdef LIBWRAP
624 #ifndef LIBWRAP_INTERNAL
625 if (sep->se_bi == 0)
626 #endif
627 if (!sep->se_wait && sep->se_socktype == SOCK_STREAM) {
628 request_init(&req, RQ_DAEMON, sep->se_argv[0] ?
629 sep->se_argv[0] : sep->se_service, RQ_FILE, ctrl, NULL);
630 fromhost(&req);
631 denied = !hosts_access(&req);
632 if (denied || lflag) {
633 sp = getservbyport(sep->se_ctrladdr_in.sin_port,
634 sep->se_proto);
635 if (sp == NULL) {
636 (void)snprintf(buf, sizeof buf, "%d",
637 ntohs(sep->se_ctrladdr_in.sin_port));
638 service = buf;
639 } else
640 service = sp->s_name;
641 }
642 if (denied) {
643 syslog(deny_severity,
644 "refused connection from %.500s, service %s (%s)",
645 eval_client(&req), service, sep->se_proto);
646 goto reject;
647 }
648 if (lflag) {
649 syslog(allow_severity,
650 "connection from %.500s, service %s (%s)",
651 eval_client(&req), service, sep->se_proto);
652 }
653 }
654 #endif /* LIBWRAP */
655
656 if (sep->se_bi) {
657 (*sep->se_bi->bi_fn)(ctrl, sep);
658 } else {
659 if ((pwd = getpwnam(sep->se_user)) == NULL) {
660 syslog(LOG_ERR, "%s/%s: %s: No such user",
661 sep->se_service, sep->se_proto, sep->se_user);
662 goto reject;
663 }
664 if (sep->se_group &&
665 (grp = getgrnam(sep->se_group)) == NULL) {
666 syslog(LOG_ERR, "%s/%s: %s: No such group",
667 sep->se_service, sep->se_proto, sep->se_group);
668 goto reject;
669 }
670 if (pwd->pw_uid) {
671 if (sep->se_group)
672 pwd->pw_gid = grp->gr_gid;
673 if (setgid(pwd->pw_gid) < 0) {
674 syslog(LOG_ERR,
675 "%s/%s: can't set gid %d: %m", sep->se_service,
676 sep->se_proto, pwd->pw_gid);
677 goto reject;
678 }
679 (void) initgroups(pwd->pw_name,
680 pwd->pw_gid);
681 if (setuid(pwd->pw_uid) < 0) {
682 syslog(LOG_ERR,
683 "%s/%s: can't set uid %d: %m", sep->se_service,
684 sep->se_proto, pwd->pw_uid);
685 goto reject;
686 }
687 } else if (sep->se_group) {
688 (void) setgid((gid_t)grp->gr_gid);
689 }
690 if (debug)
691 fprintf(stderr, "%d execl %s\n",
692 getpid(), sep->se_server);
693 #ifdef MULOG
694 if (sep->se_log)
695 dolog(sep, ctrl);
696 #endif
697 /* Set our control descriptor to not close-on-exec... */
698 if (fcntl(ctrl, F_SETFD, 0) < 0)
699 syslog(LOG_ERR, "fcntl (F_SETFD, 0): %m");
700 /* ...and dup it to stdin, stdout, and stderr. */
701 if (ctrl != 0) {
702 dup2(ctrl, 0);
703 close(ctrl);
704 ctrl = 0;
705 }
706 dup2(0, 1);
707 dup2(0, 2);
708 #ifdef RLIMIT_NOFILE
709 if (rlim_ofile.rlim_cur != rlim_ofile_cur &&
710 setrlimit(RLIMIT_NOFILE, &rlim_ofile) < 0)
711 syslog(LOG_ERR, "setrlimit: %m");
712 #endif
713 execv(sep->se_server, sep->se_argv);
714 syslog(LOG_ERR, "cannot execute %s: %m", sep->se_server);
715 reject:
716 if (sep->se_socktype != SOCK_STREAM)
717 recv(ctrl, buf, sizeof (buf), 0);
718 _exit(1);
719 }
720 }
721
722 void
723 reapchild(signo)
724 int signo;
725 {
726 int status;
727 pid_t pid;
728 struct servtab *sep;
729
730 for (;;) {
731 pid = wait3(&status, WNOHANG, (struct rusage *)0);
732 if (pid <= 0)
733 break;
734 if (debug)
735 fprintf(stderr, "%d reaped, status %#x\n",
736 pid, status);
737 for (sep = servtab; sep; sep = sep->se_next)
738 if (sep->se_wait == pid) {
739 if (WIFEXITED(status) && WEXITSTATUS(status))
740 syslog(LOG_WARNING,
741 "%s: exit status 0x%x",
742 sep->se_server, WEXITSTATUS(status));
743 else if (WIFSIGNALED(status))
744 syslog(LOG_WARNING,
745 "%s: exit signal 0x%x",
746 sep->se_server, WTERMSIG(status));
747 sep->se_wait = 1;
748 FD_SET(sep->se_fd, &allsock);
749 nsock++;
750 if (debug)
751 fprintf(stderr, "restored %s, fd %d\n",
752 sep->se_service, sep->se_fd);
753 }
754 }
755 }
756
757 void
758 config(signo)
759 int signo;
760 {
761 struct servtab *sep, *cp, **sepp;
762 long omask;
763 int n;
764
765 if (!setconfig()) {
766 syslog(LOG_ERR, "%s: %m", CONFIG);
767 return;
768 }
769 for (sep = servtab; sep; sep = sep->se_next)
770 sep->se_checked = 0;
771 while ((cp = getconfigent())) {
772 for (sep = servtab; sep; sep = sep->se_next)
773 if (strcmp(sep->se_service, cp->se_service) == 0 &&
774 strcmp(sep->se_hostaddr, cp->se_hostaddr) == 0 &&
775 strcmp(sep->se_proto, cp->se_proto) == 0 &&
776 ISMUX(sep) == ISMUX(cp))
777 break;
778 if (sep != 0) {
779 int i;
780
781 #define SWAP(type, a, b) {type c=(type)a; (type)a=(type)b; (type)b=(type)c;}
782
783 omask = sigblock(SIGBLOCK);
784 /*
785 * sep->se_wait may be holding the pid of a daemon
786 * that we're waiting for. If so, don't overwrite
787 * it unless the config file explicitly says don't
788 * wait.
789 */
790 if (cp->se_bi == 0 &&
791 (sep->se_wait == 1 || cp->se_wait == 0))
792 sep->se_wait = cp->se_wait;
793 SWAP(char *, sep->se_user, cp->se_user);
794 SWAP(char *, sep->se_group, cp->se_group);
795 SWAP(char *, sep->se_server, cp->se_server);
796 for (i = 0; i < MAXARGV; i++)
797 SWAP(char *, sep->se_argv[i], cp->se_argv[i]);
798 SWAP(int, cp->se_type, sep->se_type);
799 SWAP(int, cp->se_max, sep->se_max);
800 #undef SWAP
801 if (isrpcservice(sep))
802 unregister_rpc(sep);
803 sep->se_rpcversl = cp->se_rpcversl;
804 sep->se_rpcversh = cp->se_rpcversh;
805 sigsetmask(omask);
806 freeconfig(cp);
807 if (debug)
808 print_service("REDO", sep);
809 } else {
810 sep = enter(cp);
811 if (debug)
812 print_service("ADD ", sep);
813 }
814 sep->se_checked = 1;
815
816 switch (sep->se_family) {
817 case AF_LOCAL:
818 if (sep->se_fd != -1)
819 break;
820 n = strlen(sep->se_service);
821 if (n > sizeof(sep->se_ctrladdr_un.sun_path)) {
822 syslog(LOG_ERR, "%s: address too long",
823 sep->se_service);
824 sep->se_checked = 0;
825 continue;
826 }
827 (void)unlink(sep->se_service);
828 strncpy(sep->se_ctrladdr_un.sun_path,
829 sep->se_service, n);
830 sep->se_ctrladdr_un.sun_family = AF_LOCAL;
831 sep->se_ctrladdr_size = n +
832 sizeof(sep->se_ctrladdr_un) -
833 sizeof(sep->se_ctrladdr_un.sun_path);
834 if (!ISMUX(sep))
835 setup(sep);
836 break;
837 case AF_INET:
838 sep->se_ctrladdr_in.sin_family = AF_INET;
839 if (!strcmp(sep->se_hostaddr,"*"))
840 sep->se_ctrladdr_in.sin_addr.s_addr =
841 INADDR_ANY;
842 else if (!inet_aton(sep->se_hostaddr,
843 &sep->se_ctrladdr_in.sin_addr)) {
844 /* Do we really want to support hostname lookups here? */
845 struct hostent *hp;
846 hp = gethostbyname(sep->se_hostaddr);
847 if (hp == 0) {
848 syslog(LOG_ERR, "%s: unknown host",
849 sep->se_hostaddr);
850 sep->se_checked = 0;
851 continue;
852 } else if (hp->h_addrtype != AF_INET) {
853 syslog(LOG_ERR,
854 "%s: address isn't an Internet address",
855 sep->se_hostaddr);
856 sep->se_checked = 0;
857 continue;
858 } else if (hp->h_length != sizeof(struct in_addr)) {
859 syslog(LOG_ERR,
860 "%s: address size wrong (under DNS corruption attack?)",
861 sep->se_hostaddr);
862 sep->se_checked = 0;
863 continue;
864 } else {
865 memcpy(&sep->se_ctrladdr_in.sin_addr,
866 hp->h_addr_list[0],
867 sizeof(struct in_addr));
868 }
869 }
870 if (ISMUX(sep)) {
871 sep->se_fd = -1;
872 continue;
873 }
874 sep->se_ctrladdr_size = sizeof(sep->se_ctrladdr_in);
875 if (isrpcservice(sep)) {
876 struct rpcent *rp;
877
878 sep->se_rpcprog = atoi(sep->se_service);
879 if (sep->se_rpcprog == 0) {
880 rp = getrpcbyname(sep->se_service);
881 if (rp == 0) {
882 syslog(LOG_ERR,
883 "%s/%s: unknown service",
884 sep->se_service,
885 sep->se_proto);
886 sep->se_checked = 0;
887 continue;
888 }
889 sep->se_rpcprog = rp->r_number;
890 }
891 if (sep->se_fd == -1 && !ISMUX(sep))
892 setup(sep);
893 if (sep->se_fd != -1)
894 register_rpc(sep);
895 } else {
896 u_short port = htons(atoi(sep->se_service));
897
898 if (!port) {
899 sp = getservbyname(sep->se_service,
900 sep->se_proto);
901 if (sp == 0) {
902 syslog(LOG_ERR,
903 "%s/%s: unknown service",
904 sep->se_service,
905 sep->se_proto);
906 sep->se_checked = 0;
907 continue;
908 }
909 port = sp->s_port;
910 }
911 if (port != sep->se_ctrladdr_in.sin_port) {
912 sep->se_ctrladdr_in.sin_port = port;
913 if (sep->se_fd >= 0)
914 close_sep(sep);
915 }
916 if (sep->se_fd == -1 && !ISMUX(sep))
917 setup(sep);
918 }
919 }
920 }
921 endconfig();
922 /*
923 * Purge anything not looked at above.
924 */
925 omask = sigblock(SIGBLOCK);
926 sepp = &servtab;
927 while ((sep = *sepp)) {
928 if (sep->se_checked) {
929 sepp = &sep->se_next;
930 continue;
931 }
932 *sepp = sep->se_next;
933 if (sep->se_fd >= 0)
934 close_sep(sep);
935 if (isrpcservice(sep))
936 unregister_rpc(sep);
937 if (sep->se_family == AF_LOCAL)
938 (void)unlink(sep->se_service);
939 if (debug)
940 print_service("FREE", sep);
941 freeconfig(sep);
942 free((char *)sep);
943 }
944 (void) sigsetmask(omask);
945 }
946
947 void
948 retry(signo)
949 int signo;
950 {
951 struct servtab *sep;
952
953 timingout = 0;
954 for (sep = servtab; sep; sep = sep->se_next) {
955 if (sep->se_fd == -1 && !ISMUX(sep)) {
956 switch (sep->se_family) {
957 case AF_LOCAL:
958 case AF_INET:
959 setup(sep);
960 if (sep->se_fd != -1 && isrpcservice(sep))
961 register_rpc(sep);
962 break;
963 }
964 }
965 }
966 }
967
968 void
969 goaway(signo)
970 int signo;
971 {
972 struct servtab *sep;
973
974 for (sep = servtab; sep; sep = sep->se_next) {
975 if (sep->se_fd == -1)
976 continue;
977
978 switch (sep->se_family) {
979 case AF_LOCAL:
980 (void)unlink(sep->se_service);
981 break;
982 case AF_INET:
983 if (sep->se_wait == 1 && isrpcservice(sep))
984 unregister_rpc(sep);
985 break;
986 }
987 (void)close(sep->se_fd);
988 }
989 (void)unlink(_PATH_INETDPID);
990 exit(0);
991 }
992
993 void
994 setup(sep)
995 struct servtab *sep;
996 {
997 int on = 1;
998
999 if ((sep->se_fd = socket(sep->se_family, sep->se_socktype, 0)) < 0) {
1000 if (debug)
1001 fprintf(stderr, "socket failed on %s/%s: %s\n",
1002 sep->se_service, sep->se_proto, strerror(errno));
1003 syslog(LOG_ERR, "%s/%s: socket: %m",
1004 sep->se_service, sep->se_proto);
1005 return;
1006 }
1007 /* Set all listening sockets to close-on-exec. */
1008 if (fcntl(sep->se_fd, F_SETFD, FD_CLOEXEC) < 0)
1009 syslog(LOG_ERR, "fcntl (F_SETFD, FD_CLOEXEC): %m");
1010
1011 #define turnon(fd, opt) \
1012 setsockopt(fd, SOL_SOCKET, opt, (char *)&on, sizeof (on))
1013 if (strcmp(sep->se_proto, "tcp") == 0 && (options & SO_DEBUG) &&
1014 turnon(sep->se_fd, SO_DEBUG) < 0)
1015 syslog(LOG_ERR, "setsockopt (SO_DEBUG): %m");
1016 if (turnon(sep->se_fd, SO_REUSEADDR) < 0)
1017 syslog(LOG_ERR, "setsockopt (SO_REUSEADDR): %m");
1018 #undef turnon
1019
1020 /* Set the socket buffer sizes, if specified. */
1021 if (sep->se_sndbuf != 0 && setsockopt(sep->se_fd, SOL_SOCKET,
1022 SO_SNDBUF, (char *)&sep->se_sndbuf, sizeof(sep->se_sndbuf)) < 0)
1023 syslog(LOG_ERR, "setsockopt (SO_SNDBUF %d): %m",
1024 sep->se_sndbuf);
1025 if (sep->se_rcvbuf != 0 && setsockopt(sep->se_fd, SOL_SOCKET,
1026 SO_RCVBUF, (char *)&sep->se_rcvbuf, sizeof(sep->se_rcvbuf)) < 0)
1027 syslog(LOG_ERR, "setsockopt (SO_RCVBUF %d): %m",
1028 sep->se_rcvbuf);
1029
1030 if (bind(sep->se_fd, &sep->se_ctrladdr, sep->se_ctrladdr_size) < 0) {
1031 if (debug)
1032 fprintf(stderr, "bind failed on %s/%s: %s\n",
1033 sep->se_service, sep->se_proto, strerror(errno));
1034 syslog(LOG_ERR, "%s/%s: bind: %m",
1035 sep->se_service, sep->se_proto);
1036 (void) close(sep->se_fd);
1037 sep->se_fd = -1;
1038 if (!timingout) {
1039 timingout = 1;
1040 alarm(RETRYTIME);
1041 }
1042 return;
1043 }
1044 if (sep->se_socktype == SOCK_STREAM)
1045 listen(sep->se_fd, 10);
1046
1047 FD_SET(sep->se_fd, &allsock);
1048 nsock++;
1049 if (sep->se_fd > maxsock) {
1050 maxsock = sep->se_fd;
1051 if (maxsock > rlim_ofile_cur - FD_MARGIN)
1052 bump_nofile();
1053 }
1054 if (debug)
1055 fprintf(stderr, "registered %s on %d\n",
1056 sep->se_server, sep->se_fd);
1057 }
1058
1059 /*
1060 * Finish with a service and its socket.
1061 */
1062 void
1063 close_sep(sep)
1064 struct servtab *sep;
1065 {
1066 if (sep->se_fd >= 0) {
1067 nsock--;
1068 FD_CLR(sep->se_fd, &allsock);
1069 (void) close(sep->se_fd);
1070 sep->se_fd = -1;
1071 }
1072 sep->se_count = 0;
1073 /*
1074 * Don't keep the pid of this running deamon: when reapchild()
1075 * reaps this pid, it would erroneously increment nsock.
1076 */
1077 if (sep->se_wait > 1)
1078 sep->se_wait = 1;
1079 }
1080
1081 void
1082 register_rpc(sep)
1083 struct servtab *sep;
1084 {
1085 #ifdef RPC
1086 int n;
1087 struct sockaddr_in sin;
1088 struct protoent *pp;
1089
1090 if ((pp = getprotobyname(sep->se_proto+4)) == NULL) {
1091 syslog(LOG_ERR, "%s: getproto: %m",
1092 sep->se_proto);
1093 return;
1094 }
1095 n = sizeof sin;
1096 if (getsockname(sep->se_fd, (struct sockaddr *)&sin, &n) < 0) {
1097 syslog(LOG_ERR, "%s/%s: getsockname: %m",
1098 sep->se_service, sep->se_proto);
1099 return;
1100 }
1101
1102 for (n = sep->se_rpcversl; n <= sep->se_rpcversh; n++) {
1103 if (debug)
1104 fprintf(stderr, "pmap_set: %u %u %u %u\n",
1105 sep->se_rpcprog, n, pp->p_proto,
1106 ntohs(sin.sin_port));
1107 (void)pmap_unset(sep->se_rpcprog, n);
1108 if (!pmap_set(sep->se_rpcprog, n, pp->p_proto, ntohs(sin.sin_port)))
1109 syslog(LOG_ERR, "pmap_set: %u %u %u %u: %m",
1110 sep->se_rpcprog, n, pp->p_proto,
1111 ntohs(sin.sin_port));
1112 }
1113 #endif /* RPC */
1114 }
1115
1116 void
1117 unregister_rpc(sep)
1118 struct servtab *sep;
1119 {
1120 #ifdef RPC
1121 int n;
1122
1123 for (n = sep->se_rpcversl; n <= sep->se_rpcversh; n++) {
1124 if (debug)
1125 fprintf(stderr, "pmap_unset(%u, %u)\n",
1126 sep->se_rpcprog, n);
1127 if (!pmap_unset(sep->se_rpcprog, n))
1128 syslog(LOG_ERR, "pmap_unset(%u, %u)\n",
1129 sep->se_rpcprog, n);
1130 }
1131 #endif /* RPC */
1132 }
1133
1134
1135 struct servtab *
1136 enter(cp)
1137 struct servtab *cp;
1138 {
1139 struct servtab *sep;
1140 long omask;
1141
1142 sep = (struct servtab *)malloc(sizeof (*sep));
1143 if (sep == (struct servtab *)0) {
1144 syslog(LOG_ERR, "Out of memory.");
1145 exit(-1);
1146 }
1147 *sep = *cp;
1148 sep->se_fd = -1;
1149 sep->se_rpcprog = -1;
1150 omask = sigblock(SIGBLOCK);
1151 sep->se_next = servtab;
1152 servtab = sep;
1153 sigsetmask(omask);
1154 return (sep);
1155 }
1156
1157 FILE *fconfig = NULL;
1158 struct servtab serv;
1159 char line[LINE_MAX];
1160 char *defhost;
1161
1162 int
1163 setconfig()
1164 {
1165 if (defhost) free(defhost);
1166 defhost = newstr("*");
1167 if (fconfig != NULL) {
1168 fseek(fconfig, 0L, SEEK_SET);
1169 return (1);
1170 }
1171 fconfig = fopen(CONFIG, "r");
1172 return (fconfig != NULL);
1173 }
1174
1175 void
1176 endconfig()
1177 {
1178 if (fconfig) {
1179 (void) fclose(fconfig);
1180 fconfig = NULL;
1181 }
1182 if (defhost) {
1183 free(defhost);
1184 defhost = 0;
1185 }
1186 }
1187
1188 struct servtab *
1189 getconfigent()
1190 {
1191 struct servtab *sep = &serv;
1192 int argc, val;
1193 char *cp, *cp0, *arg, *buf0, *buf1, *sz0, *sz1;
1194 static char TCPMUX_TOKEN[] = "tcpmux/";
1195 #define MUX_LEN (sizeof(TCPMUX_TOKEN)-1)
1196 char *hostdelim;
1197
1198 more:
1199 #ifdef MULOG
1200 while ((cp = nextline(fconfig)) && (*cp == '#' || *cp == '\0')) {
1201 /* Avoid use of `skip' if there is a danger of it looking
1202 * at continuation lines.
1203 */
1204 do {
1205 cp++;
1206 } while (*cp == ' ' || *cp == '\t');
1207 if (*cp == '\0')
1208 continue;
1209 if ((arg = skip(&cp)) == NULL)
1210 continue;
1211 if (strcmp(arg, "DOMAIN"))
1212 continue;
1213 if (curdom)
1214 free(curdom);
1215 curdom = NULL;
1216 while (*cp == ' ' || *cp == '\t')
1217 cp++;
1218 if (*cp == '\0')
1219 continue;
1220 arg = cp;
1221 while (*cp && *cp != ' ' && *cp != '\t')
1222 cp++;
1223 if (*cp != '\0')
1224 *cp++ = '\0';
1225 curdom = newstr(arg);
1226 }
1227 #else
1228 while ((cp = nextline(fconfig)) && (*cp == '#' || *cp == '\0'))
1229 ;
1230 #endif
1231 if (cp == NULL)
1232 return ((struct servtab *)0);
1233 /*
1234 * clear the static buffer, since some fields (se_ctrladdr,
1235 * for example) don't get initialized here.
1236 */
1237 memset((caddr_t)sep, 0, sizeof *sep);
1238 arg = skip(&cp);
1239 if (cp == NULL) {
1240 /* got an empty line containing just blanks/tabs. */
1241 goto more;
1242 }
1243 /* Check for a host name. */
1244 hostdelim = strrchr(arg, ':');
1245 if (hostdelim) {
1246 *hostdelim = '\0';
1247 sep->se_hostaddr = newstr(arg);
1248 arg = hostdelim + 1;
1249 /*
1250 * If the line is of the form `host:', then just change the
1251 * default host for the following lines.
1252 */
1253 if (*arg == '\0') {
1254 arg = skip(&cp);
1255 if (cp == NULL) {
1256 free(defhost);
1257 defhost = sep->se_hostaddr;
1258 goto more;
1259 }
1260 }
1261 } else
1262 sep->se_hostaddr = newstr(defhost);
1263 if (strncmp(arg, TCPMUX_TOKEN, MUX_LEN) == 0) {
1264 char *c = arg + MUX_LEN;
1265 if (*c == '+') {
1266 sep->se_type = MUXPLUS_TYPE;
1267 c++;
1268 } else
1269 sep->se_type = MUX_TYPE;
1270 sep->se_service = newstr(c);
1271 } else {
1272 sep->se_service = newstr(arg);
1273 sep->se_type = NORM_TYPE;
1274 }
1275
1276 arg = sskip(&cp);
1277 if (strcmp(arg, "stream") == 0)
1278 sep->se_socktype = SOCK_STREAM;
1279 else if (strcmp(arg, "dgram") == 0)
1280 sep->se_socktype = SOCK_DGRAM;
1281 else if (strcmp(arg, "rdm") == 0)
1282 sep->se_socktype = SOCK_RDM;
1283 else if (strcmp(arg, "seqpacket") == 0)
1284 sep->se_socktype = SOCK_SEQPACKET;
1285 else if (strcmp(arg, "raw") == 0)
1286 sep->se_socktype = SOCK_RAW;
1287 else
1288 sep->se_socktype = -1;
1289
1290 sep->se_proto = newstr(sskip(&cp));
1291
1292 #define MALFORMED(arg) \
1293 do { \
1294 syslog(LOG_ERR, "%s: malformed buffer size option `%s'", \
1295 sep->se_service, (arg)); \
1296 goto more; \
1297 } while (0)
1298
1299 #define GETVAL(arg) \
1300 do { \
1301 if (!isdigit(*(arg))) \
1302 MALFORMED(arg); \
1303 val = strtol((arg), &cp0, 10); \
1304 if (cp0 != NULL) { \
1305 if (cp0[1] != '\0') \
1306 MALFORMED((arg)); \
1307 if (cp0[0] == 'k') \
1308 val *= 1024; \
1309 if (cp0[0] == 'm') \
1310 val *= 1024 * 1024; \
1311 } \
1312 if (val < 1) { \
1313 syslog(LOG_ERR, "%s: invalid buffer size `%s'", \
1314 sep->se_service, (arg)); \
1315 goto more; \
1316 } \
1317 } while (0)
1318
1319 #define ASSIGN(arg) \
1320 do { \
1321 if (strcmp((arg), "sndbuf") == 0) \
1322 sep->se_sndbuf = val; \
1323 else if (strcmp((arg), "rcvbuf") == 0) \
1324 sep->se_rcvbuf = val; \
1325 else \
1326 MALFORMED((arg)); \
1327 } while (0)
1328
1329 /*
1330 * Extract the send and receive buffer sizes before parsing
1331 * the protocol.
1332 */
1333 sep->se_sndbuf = sep->se_rcvbuf = 0;
1334 buf0 = buf1 = sz0 = sz1 = NULL;
1335 if ((buf0 = strchr(sep->se_proto, ',')) != NULL) {
1336 /* Not meaningful for Tcpmux services. */
1337 if (sep->se_type != NORM_TYPE) {
1338 syslog(LOG_ERR, "%s: can't specify buffer sizes for "
1339 "tcpmux services", sep->se_service);
1340 goto more;
1341 }
1342
1343 /* Skip the , */
1344 *buf0++ = '\0';
1345
1346 /* Check to see if another socket buffer size was specified. */
1347 if ((buf1 = strchr(buf0, ',')) != NULL) {
1348 /* Skip the , */
1349 *buf1++ = '\0';
1350
1351 /* Make sure a 3rd one wasn't specified. */
1352 if (strchr(buf1, ',') != NULL) {
1353 syslog(LOG_ERR, "%s: too many buffer sizes",
1354 sep->se_service);
1355 goto more;
1356 }
1357
1358 /* Locate the size. */
1359 if ((sz1 = strchr(buf1, '=')) == NULL)
1360 MALFORMED(buf1);
1361
1362 /* Skip the = */
1363 *sz1++ = '\0';
1364 }
1365
1366 /* Locate the size. */
1367 if ((sz0 = strchr(buf0, '=')) == NULL)
1368 MALFORMED(buf0);
1369
1370 /* Skip the = */
1371 *sz0++ = '\0';
1372
1373 GETVAL(sz0);
1374 ASSIGN(buf0);
1375
1376 if (buf1 != NULL) {
1377 GETVAL(sz1);
1378 ASSIGN(buf1);
1379 }
1380 }
1381
1382 #undef ASSIGN
1383 #undef GETVAL
1384 #undef MALFORMED
1385
1386 if (strcmp(sep->se_proto, "unix") == 0) {
1387 sep->se_family = AF_LOCAL;
1388 } else {
1389 sep->se_family = AF_INET;
1390 if (strncmp(sep->se_proto, "rpc/", 4) == 0) {
1391 #ifdef RPC
1392 char *cp, *ccp;
1393 cp = strchr(sep->se_service, '/');
1394 if (cp == 0) {
1395 syslog(LOG_ERR, "%s: no rpc version",
1396 sep->se_service);
1397 goto more;
1398 }
1399 *cp++ = '\0';
1400 sep->se_rpcversl = sep->se_rpcversh =
1401 strtol(cp, &ccp, 0);
1402 if (ccp == cp) {
1403 badafterall:
1404 syslog(LOG_ERR, "%s/%s: bad rpc version",
1405 sep->se_service, cp);
1406 goto more;
1407 }
1408 if (*ccp == '-') {
1409 cp = ccp + 1;
1410 sep->se_rpcversh = strtol(cp, &ccp, 0);
1411 if (ccp == cp)
1412 goto badafterall;
1413 }
1414 #else
1415 syslog(LOG_ERR, "%s: rpc services not suported",
1416 sep->se_service);
1417 goto more;
1418 #endif /* RPC */
1419 }
1420 }
1421 arg = sskip(&cp);
1422 {
1423 char *cp;
1424 cp = strchr(arg, '.');
1425 if (cp) {
1426 *cp++ = '\0';
1427 sep->se_max = atoi(cp);
1428 } else
1429 sep->se_max = TOOMANY;
1430 }
1431 sep->se_wait = strcmp(arg, "wait") == 0;
1432 if (ISMUX(sep)) {
1433 /*
1434 * Silently enforce "nowait" for TCPMUX services since
1435 * they don't have an assigned port to listen on.
1436 */
1437 sep->se_wait = 0;
1438
1439 if (strcmp(sep->se_proto, "tcp")) {
1440 syslog(LOG_ERR,
1441 "%s: bad protocol for tcpmux service %s",
1442 CONFIG, sep->se_service);
1443 goto more;
1444 }
1445 if (sep->se_socktype != SOCK_STREAM) {
1446 syslog(LOG_ERR,
1447 "%s: bad socket type for tcpmux service %s",
1448 CONFIG, sep->se_service);
1449 goto more;
1450 }
1451 }
1452 sep->se_user = newstr(sskip(&cp));
1453 if ((sep->se_group = strchr(sep->se_user, '.')))
1454 *sep->se_group++ = '\0';
1455 sep->se_server = newstr(sskip(&cp));
1456 if (strcmp(sep->se_server, "internal") == 0) {
1457 struct biltin *bi;
1458
1459 for (bi = biltins; bi->bi_service; bi++)
1460 if (bi->bi_socktype == sep->se_socktype &&
1461 strcmp(bi->bi_service, sep->se_service) == 0)
1462 break;
1463 if (bi->bi_service == 0) {
1464 syslog(LOG_ERR, "internal service %s unknown",
1465 sep->se_service);
1466 goto more;
1467 }
1468 sep->se_bi = bi;
1469 sep->se_wait = bi->bi_wait;
1470 } else
1471 sep->se_bi = NULL;
1472 argc = 0;
1473 for (arg = skip(&cp); cp; arg = skip(&cp)) {
1474 #if MULOG
1475 char *colon;
1476
1477 if (argc == 0 && (colon = strrchr(arg, ':'))) {
1478 while (arg < colon) {
1479 int x;
1480 char *ccp;
1481
1482 switch (*arg++) {
1483 case 'l':
1484 x = 1;
1485 if (isdigit(*arg)) {
1486 x = strtol(arg, &ccp, 0);
1487 if (ccp == arg)
1488 break;
1489 arg = ccp;
1490 }
1491 sep->se_log &= ~MULOG_RFC931;
1492 sep->se_log |= x;
1493 break;
1494 case 'a':
1495 sep->se_log |= MULOG_RFC931;
1496 break;
1497 default:
1498 break;
1499 }
1500 }
1501 arg = colon + 1;
1502 }
1503 #endif
1504 if (argc < MAXARGV)
1505 sep->se_argv[argc++] = newstr(arg);
1506 }
1507 while (argc <= MAXARGV)
1508 sep->se_argv[argc++] = NULL;
1509 return (sep);
1510 }
1511
1512 void
1513 freeconfig(cp)
1514 struct servtab *cp;
1515 {
1516 int i;
1517
1518 if (cp->se_hostaddr)
1519 free(cp->se_hostaddr);
1520 if (cp->se_service)
1521 free(cp->se_service);
1522 if (cp->se_proto)
1523 free(cp->se_proto);
1524 if (cp->se_user)
1525 free(cp->se_user);
1526 /* Note: se_group is part of the newstr'ed se_user */
1527 if (cp->se_server)
1528 free(cp->se_server);
1529 for (i = 0; i < MAXARGV; i++)
1530 if (cp->se_argv[i])
1531 free(cp->se_argv[i]);
1532 }
1533
1534
1535 /*
1536 * Safe skip - if skip returns null, log a syntax error in the
1537 * configuration file and exit.
1538 */
1539 char *
1540 sskip(cpp)
1541 char **cpp;
1542 {
1543 char *cp;
1544
1545 cp = skip(cpp);
1546 if (cp == NULL) {
1547 syslog(LOG_ERR, "%s: syntax error", CONFIG);
1548 exit(-1);
1549 }
1550 return (cp);
1551 }
1552
1553 char *
1554 skip(cpp)
1555 char **cpp;
1556 {
1557 char *cp = *cpp;
1558 char *start;
1559
1560 if (*cpp == NULL)
1561 return ((char *)0);
1562
1563 again:
1564 while (*cp == ' ' || *cp == '\t')
1565 cp++;
1566 if (*cp == '\0') {
1567 int c;
1568
1569 c = getc(fconfig);
1570 (void) ungetc(c, fconfig);
1571 if (c == ' ' || c == '\t')
1572 if ((cp = nextline(fconfig)))
1573 goto again;
1574 *cpp = (char *)0;
1575 return ((char *)0);
1576 }
1577 start = cp;
1578 while (*cp && *cp != ' ' && *cp != '\t')
1579 cp++;
1580 if (*cp != '\0')
1581 *cp++ = '\0';
1582 *cpp = cp;
1583 return (start);
1584 }
1585
1586 char *
1587 nextline(fd)
1588 FILE *fd;
1589 {
1590 char *cp;
1591
1592 if (fgets(line, sizeof (line), fd) == NULL)
1593 return ((char *)0);
1594 cp = strchr(line, '\n');
1595 if (cp)
1596 *cp = '\0';
1597 return (line);
1598 }
1599
1600 char *
1601 newstr(cp)
1602 char *cp;
1603 {
1604 if ((cp = strdup(cp ? cp : "")))
1605 return (cp);
1606 syslog(LOG_ERR, "strdup: %m");
1607 exit(-1);
1608 }
1609
1610 void
1611 inetd_setproctitle(a, s)
1612 char *a;
1613 int s;
1614 {
1615 int size;
1616 char *cp;
1617 struct sockaddr_in sin;
1618 char buf[80];
1619
1620 cp = Argv[0];
1621 size = sizeof(sin);
1622 if (getpeername(s, (struct sockaddr *)&sin, &size) == 0)
1623 (void)snprintf(buf, sizeof buf, "-%s [%s]", a,
1624 inet_ntoa(sin.sin_addr));
1625 else
1626 (void)snprintf(buf, sizeof buf, "-%s", a);
1627 strncpy(cp, buf, LastArg - cp);
1628 cp += strlen(cp);
1629 while (cp < LastArg)
1630 *cp++ = ' ';
1631 }
1632
1633 void
1634 logpid()
1635 {
1636 FILE *fp;
1637
1638 if ((fp = fopen(_PATH_INETDPID, "w")) != NULL) {
1639 fprintf(fp, "%u\n", getpid());
1640 (void)fclose(fp);
1641 }
1642 }
1643
1644 void
1645 bump_nofile()
1646 {
1647 #ifdef RLIMIT_NOFILE
1648
1649 #define FD_CHUNK 32
1650
1651 struct rlimit rl;
1652
1653 if (getrlimit(RLIMIT_NOFILE, &rl) < 0) {
1654 syslog(LOG_ERR, "getrlimit: %m");
1655 return;
1656 }
1657 rl.rlim_cur = MIN(rl.rlim_max, rl.rlim_cur + FD_CHUNK);
1658 if (rl.rlim_cur <= rlim_ofile_cur) {
1659 syslog(LOG_ERR,
1660 "bump_nofile: cannot extend file limit, max = %d",
1661 (int)rl.rlim_cur);
1662 return;
1663 }
1664
1665 if (setrlimit(RLIMIT_NOFILE, &rl) < 0) {
1666 syslog(LOG_ERR, "setrlimit: %m");
1667 return;
1668 }
1669
1670 rlim_ofile_cur = rl.rlim_cur;
1671 return;
1672
1673 #else
1674 syslog(LOG_ERR, "bump_nofile: cannot extend file limit");
1675 return;
1676 #endif
1677 }
1678
1679 /*
1680 * Internet services provided internally by inetd:
1681 */
1682 #define BUFSIZE 4096
1683
1684 /* ARGSUSED */
1685 void
1686 echo_stream(s, sep) /* Echo service -- echo data back */
1687 int s;
1688 struct servtab *sep;
1689 {
1690 char buffer[BUFSIZE];
1691 int i;
1692
1693 inetd_setproctitle(sep->se_service, s);
1694 while ((i = read(s, buffer, sizeof(buffer))) > 0 &&
1695 write(s, buffer, i) > 0)
1696 ;
1697 }
1698
1699 /* ARGSUSED */
1700 void
1701 echo_dg(s, sep) /* Echo service -- echo data back */
1702 int s;
1703 struct servtab *sep;
1704 {
1705 char buffer[BUFSIZE];
1706 int i, size;
1707 struct sockaddr sa;
1708
1709 size = sizeof(sa);
1710 if ((i = recvfrom(s, buffer, sizeof(buffer), 0, &sa, &size)) < 0)
1711 return;
1712 (void) sendto(s, buffer, i, 0, &sa, sizeof(sa));
1713 }
1714
1715 /* ARGSUSED */
1716 void
1717 discard_stream(s, sep) /* Discard service -- ignore data */
1718 int s;
1719 struct servtab *sep;
1720 {
1721 char buffer[BUFSIZE];
1722
1723 inetd_setproctitle(sep->se_service, s);
1724 while ((errno = 0, read(s, buffer, sizeof(buffer)) > 0) ||
1725 errno == EINTR)
1726 ;
1727 }
1728
1729 /* ARGSUSED */
1730 void
1731 discard_dg(s, sep) /* Discard service -- ignore data */
1732 int s;
1733 struct servtab *sep;
1734 {
1735 char buffer[BUFSIZE];
1736
1737 (void) read(s, buffer, sizeof(buffer));
1738 }
1739
1740 #include <ctype.h>
1741 #define LINESIZ 72
1742 char ring[128];
1743 char *endring;
1744
1745 void
1746 initring()
1747 {
1748 int i;
1749
1750 endring = ring;
1751
1752 for (i = 0; i <= 128; ++i)
1753 if (isprint(i))
1754 *endring++ = i;
1755 }
1756
1757 /* ARGSUSED */
1758 void
1759 chargen_stream(s, sep) /* Character generator */
1760 int s;
1761 struct servtab *sep;
1762 {
1763 int len;
1764 char *rs, text[LINESIZ+2];
1765
1766 inetd_setproctitle(sep->se_service, s);
1767
1768 if (!endring) {
1769 initring();
1770 rs = ring;
1771 }
1772
1773 text[LINESIZ] = '\r';
1774 text[LINESIZ + 1] = '\n';
1775 for (rs = ring;;) {
1776 if ((len = endring - rs) >= LINESIZ)
1777 memmove(text, rs, LINESIZ);
1778 else {
1779 memmove(text, rs, len);
1780 memmove(text + len, ring, LINESIZ - len);
1781 }
1782 if (++rs == endring)
1783 rs = ring;
1784 if (write(s, text, sizeof(text)) != sizeof(text))
1785 break;
1786 }
1787 }
1788
1789 /* ARGSUSED */
1790 void
1791 chargen_dg(s, sep) /* Character generator */
1792 int s;
1793 struct servtab *sep;
1794 {
1795 struct sockaddr sa;
1796 static char *rs;
1797 int len, size;
1798 char text[LINESIZ+2];
1799
1800 if (endring == 0) {
1801 initring();
1802 rs = ring;
1803 }
1804
1805 size = sizeof(sa);
1806 if (recvfrom(s, text, sizeof(text), 0, &sa, &size) < 0)
1807 return;
1808
1809 if ((len = endring - rs) >= LINESIZ)
1810 memmove(text, rs, LINESIZ);
1811 else {
1812 memmove(text, rs, len);
1813 memmove(text + len, ring, LINESIZ - len);
1814 }
1815 if (++rs == endring)
1816 rs = ring;
1817 text[LINESIZ] = '\r';
1818 text[LINESIZ + 1] = '\n';
1819 (void) sendto(s, text, sizeof(text), 0, &sa, sizeof(sa));
1820 }
1821
1822 /*
1823 * Return a machine readable date and time, in the form of the
1824 * number of seconds since midnight, Jan 1, 1900. Since gettimeofday
1825 * returns the number of seconds since midnight, Jan 1, 1970,
1826 * we must add 2208988800 seconds to this figure to make up for
1827 * some seventy years Bell Labs was asleep.
1828 */
1829
1830 long
1831 machtime()
1832 {
1833 struct timeval tv;
1834
1835 if (gettimeofday(&tv, (struct timezone *)0) < 0) {
1836 if (debug)
1837 fprintf(stderr, "Unable to get time of day\n");
1838 return (0L);
1839 }
1840 #define OFFSET ((u_long)25567 * 24*60*60)
1841 return (htonl((long)(tv.tv_sec + OFFSET)));
1842 #undef OFFSET
1843 }
1844
1845 /* ARGSUSED */
1846 void
1847 machtime_stream(s, sep)
1848 int s;
1849 struct servtab *sep;
1850 {
1851 long result;
1852
1853 result = machtime();
1854 (void) write(s, (char *) &result, sizeof(result));
1855 }
1856
1857 /* ARGSUSED */
1858 void
1859 machtime_dg(s, sep)
1860 int s;
1861 struct servtab *sep;
1862 {
1863 long result;
1864 struct sockaddr sa;
1865 int size;
1866
1867 size = sizeof(sa);
1868 if (recvfrom(s, (char *)&result, sizeof(result), 0, &sa, &size) < 0)
1869 return;
1870 result = machtime();
1871 (void) sendto(s, (char *) &result, sizeof(result), 0, &sa, sizeof(sa));
1872 }
1873
1874 /* ARGSUSED */
1875 void
1876 daytime_stream(s, sep) /* Return human-readable time of day */
1877 int s;
1878 struct servtab *sep;
1879 {
1880 char buffer[256];
1881 time_t clock;
1882 int len;
1883
1884 clock = time((time_t *) 0);
1885
1886 len = snprintf(buffer, sizeof buffer, "%.24s\r\n", ctime(&clock));
1887 (void) write(s, buffer, len);
1888 }
1889
1890 /* ARGSUSED */
1891 void
1892 daytime_dg(s, sep) /* Return human-readable time of day */
1893 int s;
1894 struct servtab *sep;
1895 {
1896 char buffer[256];
1897 time_t clock;
1898 struct sockaddr sa;
1899 int size, len;
1900
1901 clock = time((time_t *) 0);
1902
1903 size = sizeof(sa);
1904 if (recvfrom(s, buffer, sizeof(buffer), 0, &sa, &size) < 0)
1905 return;
1906 len = snprintf(buffer, sizeof buffer, "%.24s\r\n", ctime(&clock));
1907 (void) sendto(s, buffer, len, 0, &sa, sizeof(sa));
1908 }
1909
1910 /*
1911 * print_service:
1912 * Dump relevant information to stderr
1913 */
1914 void
1915 print_service(action, sep)
1916 char *action;
1917 struct servtab *sep;
1918 {
1919 if (isrpcservice(sep))
1920 fprintf(stderr,
1921 "%s: %s rpcprog=%d, rpcvers = %d/%d, proto=%s, wait.max=%d.%d, user.group=%s.%s builtin=%lx server=%s\n",
1922 action, sep->se_service,
1923 sep->se_rpcprog, sep->se_rpcversh, sep->se_rpcversl, sep->se_proto,
1924 sep->se_wait, sep->se_max, sep->se_user, sep->se_group,
1925 (long)sep->se_bi, sep->se_server);
1926 else
1927 fprintf(stderr,
1928 "%s: %s proto=%s, wait.max=%d.%d, user.group=%s.%s builtin=%lx server=%s\n",
1929 action, sep->se_service, sep->se_proto,
1930 sep->se_wait, sep->se_max, sep->se_user, sep->se_group,
1931 (long)sep->se_bi, sep->se_server);
1932 }
1933
1934 void
1935 usage()
1936 {
1937
1938 #ifdef LIBWRAP
1939 (void)fprintf(stderr, "usage: %s [-dl] [conf]\n", __progname);
1940 #else
1941 (void)fprintf(stderr, "usage: %s [-d] [conf]\n", __progname);
1942 #endif
1943 exit(1);
1944 }
1945
1946
1947 /*
1948 * Based on TCPMUX.C by Mark K. Lottor November 1988
1949 * sri-nic::ps:<mkl>tcpmux.c
1950 */
1951
1952 static int /* # of characters upto \r,\n or \0 */
1953 getline(fd, buf, len)
1954 int fd;
1955 char *buf;
1956 int len;
1957 {
1958 int count = 0, n;
1959
1960 do {
1961 n = read(fd, buf, len-count);
1962 if (n == 0)
1963 return (count);
1964 if (n < 0)
1965 return (-1);
1966 while (--n >= 0) {
1967 if (*buf == '\r' || *buf == '\n' || *buf == '\0')
1968 return (count);
1969 count++;
1970 buf++;
1971 }
1972 } while (count < len);
1973 return (count);
1974 }
1975
1976 #define MAX_SERV_LEN (256+2) /* 2 bytes for \r\n */
1977
1978 #define strwrite(fd, buf) (void) write(fd, buf, sizeof(buf)-1)
1979
1980 void
1981 tcpmux(ctrl, sep)
1982 int ctrl;
1983 struct servtab *sep;
1984 {
1985 char service[MAX_SERV_LEN+1];
1986 int len;
1987
1988 /* Get requested service name */
1989 if ((len = getline(ctrl, service, MAX_SERV_LEN)) < 0) {
1990 strwrite(ctrl, "-Error reading service name\r\n");
1991 goto reject;
1992 }
1993 service[len] = '\0';
1994
1995 if (debug)
1996 fprintf(stderr, "tcpmux: someone wants %s\n", service);
1997
1998 /*
1999 * Help is a required command, and lists available services,
2000 * one per line.
2001 */
2002 if (!strcasecmp(service, "help")) {
2003 strwrite(ctrl, "+Available services:\r\n");
2004 strwrite(ctrl, "help\r\n");
2005 for (sep = servtab; sep; sep = sep->se_next) {
2006 if (!ISMUX(sep))
2007 continue;
2008 (void)write(ctrl, sep->se_service,
2009 strlen(sep->se_service));
2010 strwrite(ctrl, "\r\n");
2011 }
2012 goto reject;
2013 }
2014
2015 /* Try matching a service in inetd.conf with the request */
2016 for (sep = servtab; sep; sep = sep->se_next) {
2017 if (!ISMUX(sep))
2018 continue;
2019 if (!strcasecmp(service, sep->se_service)) {
2020 if (ISMUXPLUS(sep))
2021 strwrite(ctrl, "+Go\r\n");
2022 run_service(ctrl, sep);
2023 return;
2024 }
2025 }
2026 strwrite(ctrl, "-Service not available\r\n");
2027 reject:
2028 _exit(1);
2029 }
2030
2031
2032 #ifdef MULOG
2033 dolog(sep, ctrl)
2034 struct servtab *sep;
2035 int ctrl;
2036 {
2037 struct sockaddr sa;
2038 struct sockaddr_in *sin = (struct sockaddr_in *)&sa;
2039 int len = sizeof(sa);
2040 struct hostent *hp;
2041 char *host, *dp, buf[BUFSIZ], *rfc931_name();
2042 int connected = 1;
2043
2044 if (sep->se_family != AF_INET)
2045 return;
2046
2047 if (getpeername(ctrl, &sa, &len) < 0) {
2048 if (errno != ENOTCONN) {
2049 syslog(LOG_ERR, "getpeername: %m");
2050 return;
2051 }
2052 if (recvfrom(ctrl, buf, sizeof(buf), MSG_PEEK, &sa, &len) < 0) {
2053 syslog(LOG_ERR, "recvfrom: %m");
2054 return;
2055 }
2056 connected = 0;
2057 }
2058 if (sa.sa_family != AF_INET) {
2059 syslog(LOG_ERR, "unexpected address family %u", sa.sa_family);
2060 return;
2061 }
2062
2063 hp = gethostbyaddr((char *) &sin->sin_addr.s_addr,
2064 sizeof (sin->sin_addr.s_addr), AF_INET);
2065
2066 host = hp?hp->h_name:inet_ntoa(sin->sin_addr);
2067
2068 switch (sep->se_log & ~MULOG_RFC931) {
2069 case 0:
2070 return;
2071 case 1:
2072 if (curdom == NULL || *curdom == '\0')
2073 break;
2074 dp = host + strlen(host) - strlen(curdom);
2075 if (dp < host)
2076 break;
2077 if (debug)
2078 fprintf(stderr, "check \"%s\" against curdom \"%s\"\n",
2079 host, curdom);
2080 if (strcasecmp(dp, curdom) == 0)
2081 return;
2082 break;
2083 case 2:
2084 default:
2085 break;
2086 }
2087
2088 openlog("", LOG_NOWAIT, MULOG);
2089
2090 if (connected && (sep->se_log & MULOG_RFC931))
2091 syslog(LOG_INFO, "%s@%s wants %s",
2092 rfc931_name(sin, ctrl), host, sep->se_service);
2093 else
2094 syslog(LOG_INFO, "%s wants %s",
2095 host, sep->se_service);
2096 }
2097
2098 /*
2099 * From tcp_log by
2100 * Wietse Venema, Eindhoven University of Technology, The Netherlands.
2101 */
2102 #if 0
2103 static char sccsid[] = "@(#) rfc931.c 1.3 92/08/31 22:54:46";
2104 #endif
2105
2106 #include <setjmp.h>
2107
2108 #define RFC931_PORT 113 /* Semi-well-known port */
2109 #define TIMEOUT 4
2110 #define TIMEOUT2 10
2111
2112 static jmp_buf timebuf;
2113
2114 /* timeout - handle timeouts */
2115
2116 static void timeout(sig)
2117 int sig;
2118 {
2119 longjmp(timebuf, sig);
2120 }
2121
2122 /* rfc931_name - return remote user name */
2123
2124 char *
2125 rfc931_name(there, ctrl)
2126 struct sockaddr_in *there; /* remote link information */
2127 int ctrl;
2128 {
2129 struct sockaddr_in here; /* local link information */
2130 struct sockaddr_in sin; /* for talking to RFC931 daemon */
2131 int length;
2132 int s;
2133 unsigned remote;
2134 unsigned local;
2135 static char user[256]; /* XXX */
2136 char buf[256];
2137 char *cp;
2138 char *result = "USER_UNKNOWN";
2139 int len;
2140
2141 /* Find out local port number of our stdin. */
2142
2143 length = sizeof(here);
2144 if (getsockname(ctrl, (struct sockaddr *) &here, &length) == -1) {
2145 syslog(LOG_ERR, "getsockname: %m");
2146 return (result);
2147 }
2148 /* Set up timer so we won't get stuck. */
2149
2150 if ((s = socket(AF_INET, SOCK_STREAM, 0)) == -1) {
2151 syslog(LOG_ERR, "socket: %m");
2152 return (result);
2153 }
2154
2155 sin = here;
2156 sin.sin_port = htons(0);
2157 if (bind(s, (struct sockaddr *) &sin, sizeof(sin)) == -1) {
2158 syslog(LOG_ERR, "bind: %m");
2159 return (result);
2160 }
2161
2162 signal(SIGALRM, timeout);
2163 if (setjmp(timebuf)) {
2164 close(s); /* not: fclose(fp) */
2165 return (result);
2166 }
2167 alarm(TIMEOUT);
2168
2169 /* Connect to the RFC931 daemon. */
2170
2171 sin = *there;
2172 sin.sin_port = htons(RFC931_PORT);
2173 if (connect(s, (struct sockaddr *) &sin, sizeof(sin)) == -1) {
2174 close(s);
2175 alarm(0);
2176 return (result);
2177 }
2178
2179 /* Query the RFC 931 server. Would 13-byte writes ever be broken up? */
2180 (void)snprintf(buf, sizeof buf, "%u,%u\r\n", ntohs(there->sin_port),
2181 ntohs(here.sin_port));
2182
2183
2184 for (len = 0, cp = buf; len < strlen(buf); ) {
2185 int n;
2186
2187 if ((n = write(s, cp, strlen(buf) - len)) == -1) {
2188 close(s);
2189 alarm(0);
2190 return (result);
2191 }
2192 cp += n;
2193 len += n;
2194 }
2195
2196 /* Read response */
2197 for (cp = buf; cp < buf + sizeof(buf) - 1; ) {
2198 char c;
2199 if (read(s, &c, 1) != 1) {
2200 close(s);
2201 alarm(0);
2202 return (result);
2203 }
2204 if (c == '\n')
2205 break;
2206 *cp++ = c;
2207 }
2208 *cp = '\0';
2209
2210 if (sscanf(buf, "%u , %u : USERID :%*[^:]:%255s", &remote, &local, user) == 3
2211 && ntohs(there->sin_port) == remote
2212 && ntohs(here.sin_port) == local) {
2213
2214 /* Strip trailing carriage return. */
2215 if (cp = strchr(user, '\r'))
2216 *cp = 0;
2217 result = user;
2218 }
2219
2220 alarm(0);
2221 close(s);
2222 return (result);
2223 }
2224 #endif
2225