inetd.c revision 1.120 1 /* $NetBSD: inetd.c,v 1.120 2012/01/04 16:09:43 drochner Exp $ */
2
3 /*-
4 * Copyright (c) 1998, 2003 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 and by Matthias Scheler.
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 *
20 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
22 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
23 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
24 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
25 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
26 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
29 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30 * POSSIBILITY OF SUCH DAMAGE.
31 */
32
33 /*
34 * Copyright (c) 1983, 1991, 1993, 1994
35 * The Regents of the University of California. All rights reserved.
36 *
37 * Redistribution and use in source and binary forms, with or without
38 * modification, are permitted provided that the following conditions
39 * are met:
40 * 1. Redistributions of source code must retain the above copyright
41 * notice, this list of conditions and the following disclaimer.
42 * 2. Redistributions in binary form must reproduce the above copyright
43 * notice, this list of conditions and the following disclaimer in the
44 * documentation and/or other materials provided with the distribution.
45 * 3. Neither the name of the University nor the names of its contributors
46 * may be used to endorse or promote products derived from this software
47 * without specific prior written permission.
48 *
49 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
50 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
51 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
52 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
53 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
54 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
55 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
56 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
57 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
58 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
59 * SUCH DAMAGE.
60 */
61
62 #include <sys/cdefs.h>
63 #ifndef lint
64 __COPYRIGHT("@(#) Copyright (c) 1983, 1991, 1993, 1994\
65 The Regents of the University of California. All rights reserved.");
66 #if 0
67 static char sccsid[] = "@(#)inetd.c 8.4 (Berkeley) 4/13/94";
68 #else
69 __RCSID("$NetBSD: inetd.c,v 1.120 2012/01/04 16:09:43 drochner Exp $");
70 #endif
71 #endif /* not lint */
72
73 /*
74 * Inetd - Internet super-server
75 *
76 * This program invokes all internet services as needed. Connection-oriented
77 * services are invoked each time a connection is made, by creating a process.
78 * This process is passed the connection as file descriptor 0 and is expected
79 * to do a getpeername to find out the source host and port.
80 *
81 * Datagram oriented services are invoked when a datagram
82 * arrives; a process is created and passed a pending message
83 * on file descriptor 0. Datagram servers may either connect
84 * to their peer, freeing up the original socket for inetd
85 * to receive further messages on, or ``take over the socket'',
86 * processing all arriving datagrams and, eventually, timing
87 * out. The first type of server is said to be ``multi-threaded'';
88 * the second type of server ``single-threaded''.
89 *
90 * Inetd uses a configuration file which is read at startup
91 * and, possibly, at some later time in response to a hangup signal.
92 * The configuration file is ``free format'' with fields given in the
93 * order shown below. Continuation lines for an entry must being with
94 * a space or tab. All fields must be present in each entry.
95 *
96 * service name must be in /etc/services or must
97 * name a tcpmux service
98 * socket type[:accf[,arg]] stream/dgram/raw/rdm/seqpacket,
99 only stream can name an accept filter
100 * protocol must be in /etc/protocols
101 * wait/nowait[:max] single-threaded/multi-threaded, max #
102 * user[:group] user/group to run daemon as
103 * server program full path name
104 * server program arguments maximum of MAXARGS (20)
105 *
106 * For RPC services
107 * service name/version must be in /etc/rpc
108 * socket type stream/dgram/raw/rdm/seqpacket
109 * protocol must be in /etc/protocols
110 * wait/nowait[:max] single-threaded/multi-threaded
111 * user[:group] user to run daemon as
112 * server program full path name
113 * server program arguments maximum of MAXARGS (20)
114 *
115 * For non-RPC services, the "service name" can be of the form
116 * hostaddress:servicename, in which case the hostaddress is used
117 * as the host portion of the address to listen on. If hostaddress
118 * consists of a single `*' character, INADDR_ANY is used.
119 *
120 * A line can also consist of just
121 * hostaddress:
122 * where hostaddress is as in the preceding paragraph. Such a line must
123 * have no further fields; the specified hostaddress is remembered and
124 * used for all further lines that have no hostaddress specified,
125 * until the next such line (or EOF). (This is why * is provided to
126 * allow explicit specification of INADDR_ANY.) A line
127 * *:
128 * is implicitly in effect at the beginning of the file.
129 *
130 * The hostaddress specifier may (and often will) contain dots;
131 * the service name must not.
132 *
133 * For RPC services, host-address specifiers are accepted and will
134 * work to some extent; however, because of limitations in the
135 * portmapper interface, it will not work to try to give more than
136 * one line for any given RPC service, even if the host-address
137 * specifiers are different.
138 *
139 * TCP services without official port numbers are handled with the
140 * RFC1078-based tcpmux internal service. Tcpmux listens on port 1 for
141 * requests. When a connection is made from a foreign host, the service
142 * requested is passed to tcpmux, which looks it up in the servtab list
143 * and returns the proper entry for the service. Tcpmux returns a
144 * negative reply if the service doesn't exist, otherwise the invoked
145 * server is expected to return the positive reply if the service type in
146 * inetd.conf file has the prefix "tcpmux/". If the service type has the
147 * prefix "tcpmux/+", tcpmux will return the positive reply for the
148 * process; this is for compatibility with older server code, and also
149 * allows you to invoke programs that use stdin/stdout without putting any
150 * special server code in them. Services that use tcpmux are "nowait"
151 * because they do not have a well-known port and hence cannot listen
152 * for new requests.
153 *
154 * Comment lines are indicated by a `#' in column 1.
155 *
156 * #ifdef IPSEC
157 * Comment lines that start with "#@" denote IPsec policy string, as described
158 * in ipsec_set_policy(3). This will affect all the following items in
159 * inetd.conf(8). To reset the policy, just use "#@" line. By default,
160 * there's no IPsec policy.
161 * #endif
162 */
163
164 /*
165 * Here's the scoop concerning the user:group feature:
166 *
167 * 1) set-group-option off.
168 *
169 * a) user = root: NO setuid() or setgid() is done
170 *
171 * b) other: setuid()
172 * setgid(primary group as found in passwd)
173 * initgroups(name, primary group)
174 *
175 * 2) set-group-option on.
176 *
177 * a) user = root: NO setuid()
178 * setgid(specified group)
179 * NO initgroups()
180 *
181 * b) other: setuid()
182 * setgid(specified group)
183 * initgroups(name, specified group)
184 *
185 */
186
187 #include <sys/param.h>
188 #include <sys/stat.h>
189 #include <sys/ioctl.h>
190 #include <sys/socket.h>
191 #include <sys/un.h>
192 #include <sys/wait.h>
193 #include <sys/time.h>
194 #include <sys/resource.h>
195 #include <sys/event.h>
196
197 #ifndef NO_RPC
198 #define RPC
199 #endif
200
201 #include <net/if.h>
202
203 #include <netinet/in.h>
204 #include <arpa/inet.h>
205 #ifdef RPC
206 #include <rpc/rpc.h>
207 #include <rpc/rpcb_clnt.h>
208 #include <netconfig.h>
209 #endif
210
211 #include <ctype.h>
212 #include <errno.h>
213 #include <fcntl.h>
214 #include <grp.h>
215 #include <netdb.h>
216 #include <pwd.h>
217 #include <signal.h>
218 #include <stdio.h>
219 #include <stdlib.h>
220 #include <string.h>
221 #include <syslog.h>
222 #include <unistd.h>
223 #include <util.h>
224 #include <ifaddrs.h>
225
226 #include "pathnames.h"
227
228 #ifdef IPSEC
229 #include <netipsec/ipsec.h>
230 #ifndef IPSEC_POLICY_IPSEC /* no ipsec support on old ipsec */
231 #undef IPSEC
232 #endif
233 #include "ipsec.h"
234 #endif
235
236 #ifdef LIBWRAP
237 # include <tcpd.h>
238 #ifndef LIBWRAP_ALLOW_FACILITY
239 # define LIBWRAP_ALLOW_FACILITY LOG_AUTH
240 #endif
241 #ifndef LIBWRAP_ALLOW_SEVERITY
242 # define LIBWRAP_ALLOW_SEVERITY LOG_INFO
243 #endif
244 #ifndef LIBWRAP_DENY_FACILITY
245 # define LIBWRAP_DENY_FACILITY LOG_AUTH
246 #endif
247 #ifndef LIBWRAP_DENY_SEVERITY
248 # define LIBWRAP_DENY_SEVERITY LOG_WARNING
249 #endif
250 int allow_severity = LIBWRAP_ALLOW_FACILITY|LIBWRAP_ALLOW_SEVERITY;
251 int deny_severity = LIBWRAP_DENY_FACILITY|LIBWRAP_DENY_SEVERITY;
252 #endif
253
254 #define TOOMANY 40 /* don't start more than TOOMANY */
255 #define CNT_INTVL 60 /* servers in CNT_INTVL sec. */
256 #define RETRYTIME (60*10) /* retry after bind or server fail */
257
258 #define A_CNT(a) (sizeof (a) / sizeof (a[0]))
259
260 int debug;
261 #ifdef LIBWRAP
262 int lflag;
263 #endif
264 int maxsock;
265 int kq;
266 int options;
267 int timingout;
268 const int niflags = NI_NUMERICHOST | NI_NUMERICSERV;
269
270 #ifndef OPEN_MAX
271 #define OPEN_MAX 64
272 #endif
273
274 /* Reserve some descriptors, 3 stdio + at least: 1 log, 1 conf. file */
275 #define FD_MARGIN (8)
276 rlim_t rlim_ofile_cur = OPEN_MAX;
277
278 struct rlimit rlim_ofile;
279
280 struct kevent changebuf[64];
281 size_t changes;
282
283 struct servtab {
284 char *se_hostaddr; /* host address to listen on */
285 char *se_service; /* name of service */
286 int se_socktype; /* type of socket to use */
287 int se_family; /* address family */
288 char *se_proto; /* protocol used */
289 int se_sndbuf; /* sndbuf size */
290 int se_rcvbuf; /* rcvbuf size */
291 int se_rpcprog; /* rpc program number */
292 int se_rpcversl; /* rpc program lowest version */
293 int se_rpcversh; /* rpc program highest version */
294 #define isrpcservice(sep) ((sep)->se_rpcversl != 0)
295 pid_t se_wait; /* single threaded server */
296 short se_checked; /* looked at during merge */
297 char *se_user; /* user name to run as */
298 char *se_group; /* group name to run as */
299 struct biltin *se_bi; /* if built-in, description */
300 char *se_server; /* server program */
301 #define MAXARGV 20
302 char *se_argv[MAXARGV+1]; /* program arguments */
303 #ifdef IPSEC
304 char *se_policy; /* IPsec poilcy string */
305 #endif
306 struct accept_filter_arg se_accf; /* accept filter for stream service */
307 int se_fd; /* open descriptor */
308 int se_type; /* type */
309 union {
310 struct sockaddr se_un_ctrladdr;
311 struct sockaddr_in se_un_ctrladdr_in;
312 struct sockaddr_in6 se_un_ctrladdr_in6;
313 struct sockaddr_un se_un_ctrladdr_un;
314 } se_un; /* bound address */
315 #define se_ctrladdr se_un.se_un_ctrladdr
316 #define se_ctrladdr_in se_un.se_un_ctrladdr_in
317 #define se_ctrladdr_un se_un.se_un_ctrladdr_un
318 int se_ctrladdr_size;
319 int se_max; /* max # of instances of this service */
320 int se_count; /* number started since se_time */
321 struct timeval se_time; /* start of se_count */
322 struct servtab *se_next;
323 } *servtab;
324
325 #define NORM_TYPE 0
326 #define MUX_TYPE 1
327 #define MUXPLUS_TYPE 2
328 #define FAITH_TYPE 3
329 #define ISMUX(sep) (((sep)->se_type == MUX_TYPE) || \
330 ((sep)->se_type == MUXPLUS_TYPE))
331 #define ISMUXPLUS(sep) ((sep)->se_type == MUXPLUS_TYPE)
332
333
334 static void chargen_dg(int, struct servtab *);
335 static void chargen_stream(int, struct servtab *);
336 static void close_sep(struct servtab *);
337 static void config(void);
338 static void daytime_dg(int, struct servtab *);
339 static void daytime_stream(int, struct servtab *);
340 static void discard_dg(int, struct servtab *);
341 static void discard_stream(int, struct servtab *);
342 static void echo_dg(int, struct servtab *);
343 static void echo_stream(int, struct servtab *);
344 static void endconfig(void);
345 static struct servtab *enter(struct servtab *);
346 static void freeconfig(struct servtab *);
347 static struct servtab *getconfigent(void);
348 __dead static void goaway(void);
349 static void machtime_dg(int, struct servtab *);
350 static void machtime_stream(int, struct servtab *);
351 static char *newstr(const char *);
352 static char *nextline(FILE *);
353 static void print_service(const char *, struct servtab *);
354 static void reapchild(void);
355 static void retry(void);
356 static void run_service(int, struct servtab *, int);
357 static int setconfig(void);
358 static void setup(struct servtab *);
359 static char *sskip(char **);
360 static char *skip(char **);
361 static void tcpmux(int, struct servtab *);
362 __dead static void usage(void);
363 static void register_rpc(struct servtab *);
364 static void unregister_rpc(struct servtab *);
365 static void bump_nofile(void);
366 static void inetd_setproctitle(char *, int);
367 static void initring(void);
368 static uint32_t machtime(void);
369 static int port_good_dg(struct sockaddr *);
370 static int dg_broadcast(struct in_addr *);
371 static int my_kevent(const struct kevent *, size_t, struct kevent *,
372 size_t);
373 static struct kevent * allocchange(void);
374 static int get_line(int, char *, int);
375 static void spawn(struct servtab *, int);
376
377 struct biltin {
378 const char *bi_service; /* internally provided service name */
379 int bi_socktype; /* type of socket supported */
380 short bi_fork; /* 1 if should fork before call */
381 short bi_wait; /* 1 if should wait for child */
382 void (*bi_fn)(int, struct servtab *);
383 /* function which performs it */
384 } biltins[] = {
385 /* Echo received data */
386 { "echo", SOCK_STREAM, 1, 0, echo_stream },
387 { "echo", SOCK_DGRAM, 0, 0, echo_dg },
388
389 /* Internet /dev/null */
390 { "discard", SOCK_STREAM, 1, 0, discard_stream },
391 { "discard", SOCK_DGRAM, 0, 0, discard_dg },
392
393 /* Return 32 bit time since 1970 */
394 { "time", SOCK_STREAM, 0, 0, machtime_stream },
395 { "time", SOCK_DGRAM, 0, 0, machtime_dg },
396
397 /* Return human-readable time */
398 { "daytime", SOCK_STREAM, 0, 0, daytime_stream },
399 { "daytime", SOCK_DGRAM, 0, 0, daytime_dg },
400
401 /* Familiar character generator */
402 { "chargen", SOCK_STREAM, 1, 0, chargen_stream },
403 { "chargen", SOCK_DGRAM, 0, 0, chargen_dg },
404
405 { "tcpmux", SOCK_STREAM, 1, 0, tcpmux },
406
407 { NULL, 0, 0, 0, NULL }
408 };
409
410 /* list of "bad" ports. I.e. ports that are most obviously used for
411 * "cycling packets" denial of service attacks. See /etc/services.
412 * List must end with port number "0".
413 */
414
415 u_int16_t bad_ports[] = { 7, 9, 13, 19, 37, 0 };
416
417
418 #define NUMINT (sizeof(intab) / sizeof(struct inent))
419 const char *CONFIG = _PATH_INETDCONF;
420
421 static int my_signals[] =
422 { SIGALRM, SIGHUP, SIGCHLD, SIGTERM, SIGINT, SIGPIPE };
423
424 int
425 main(int argc, char *argv[])
426 {
427 int ch, n, reload = 1;
428
429 while ((ch = getopt(argc, argv,
430 #ifdef LIBWRAP
431 "dl"
432 #else
433 "d"
434 #endif
435 )) != -1)
436 switch(ch) {
437 case 'd':
438 debug = 1;
439 options |= SO_DEBUG;
440 break;
441 #ifdef LIBWRAP
442 case 'l':
443 lflag = 1;
444 break;
445 #endif
446 case '?':
447 default:
448 usage();
449 }
450 argc -= optind;
451 argv += optind;
452
453 if (argc > 0)
454 CONFIG = argv[0];
455
456 if (!debug)
457 daemon(0, 0);
458 openlog("inetd", LOG_PID | LOG_NOWAIT, LOG_DAEMON);
459 pidfile(NULL);
460
461 kq = kqueue();
462 if (kq < 0) {
463 syslog(LOG_ERR, "kqueue: %m");
464 return (EXIT_FAILURE);
465 }
466
467 if (getrlimit(RLIMIT_NOFILE, &rlim_ofile) < 0) {
468 syslog(LOG_ERR, "getrlimit: %m");
469 } else {
470 rlim_ofile_cur = rlim_ofile.rlim_cur;
471 if (rlim_ofile_cur == RLIM_INFINITY) /* ! */
472 rlim_ofile_cur = OPEN_MAX;
473 }
474
475 for (n = 0; n < (int)A_CNT(my_signals); n++) {
476 int signum;
477
478 signum = my_signals[n];
479 if (signum != SIGCHLD)
480 (void) signal(signum, SIG_IGN);
481
482 if (signum != SIGPIPE) {
483 struct kevent *ev;
484
485 ev = allocchange();
486 EV_SET(ev, signum, EVFILT_SIGNAL, EV_ADD | EV_ENABLE,
487 0, 0, 0);
488 }
489 }
490
491 for (;;) {
492 int ctrl;
493 struct kevent eventbuf[64], *ev;
494 struct servtab *sep;
495
496 if (reload) {
497 reload = 0;
498 config();
499 }
500
501 n = my_kevent(changebuf, changes, eventbuf, A_CNT(eventbuf));
502 changes = 0;
503
504 for (ev = eventbuf; n > 0; ev++, n--) {
505 if (ev->filter == EVFILT_SIGNAL) {
506 switch (ev->ident) {
507 case SIGALRM:
508 retry();
509 break;
510 case SIGCHLD:
511 reapchild();
512 break;
513 case SIGTERM:
514 case SIGINT:
515 goaway();
516 break;
517 case SIGHUP:
518 reload = 1;
519 break;
520 }
521 continue;
522 }
523 if (ev->filter != EVFILT_READ)
524 continue;
525 sep = (struct servtab *)ev->udata;
526 /* Paranoia */
527 if ((int)ev->ident != sep->se_fd)
528 continue;
529 if (debug)
530 fprintf(stderr, "someone wants %s\n",
531 sep->se_service);
532 if (!sep->se_wait && sep->se_socktype == SOCK_STREAM) {
533 /* XXX here do the libwrap check-before-accept*/
534 ctrl = accept(sep->se_fd, NULL, NULL);
535 if (debug)
536 fprintf(stderr, "accept, ctrl %d\n",
537 ctrl);
538 if (ctrl < 0) {
539 if (errno != EINTR)
540 syslog(LOG_WARNING,
541 "accept (for %s): %m",
542 sep->se_service);
543 continue;
544 }
545 } else
546 ctrl = sep->se_fd;
547 spawn(sep, ctrl);
548 }
549 }
550 }
551
552 static void
553 spawn(struct servtab *sep, int ctrl)
554 {
555 int dofork;
556 pid_t pid;
557
558 pid = 0;
559 #ifdef LIBWRAP_INTERNAL
560 dofork = 1;
561 #else
562 dofork = (sep->se_bi == 0 || sep->se_bi->bi_fork);
563 #endif
564 if (dofork) {
565 if (sep->se_count++ == 0)
566 (void)gettimeofday(&sep->se_time, NULL);
567 else if (sep->se_count >= sep->se_max) {
568 struct timeval now;
569
570 (void)gettimeofday(&now, NULL);
571 if (now.tv_sec - sep->se_time.tv_sec > CNT_INTVL) {
572 sep->se_time = now;
573 sep->se_count = 1;
574 } else {
575 syslog(LOG_ERR,
576 "%s/%s max spawn rate (%d in %d seconds) "
577 "exceeded; service not started",
578 sep->se_service, sep->se_proto,
579 sep->se_max, CNT_INTVL);
580 if (!sep->se_wait && sep->se_socktype ==
581 SOCK_STREAM)
582 close(ctrl);
583 close_sep(sep);
584 if (!timingout) {
585 timingout = 1;
586 alarm(RETRYTIME);
587 }
588 return;
589 }
590 }
591 pid = fork();
592 if (pid < 0) {
593 syslog(LOG_ERR, "fork: %m");
594 if (!sep->se_wait && sep->se_socktype == SOCK_STREAM)
595 close(ctrl);
596 sleep(1);
597 return;
598 }
599 if (pid != 0 && sep->se_wait) {
600 struct kevent *ev;
601
602 sep->se_wait = pid;
603 ev = allocchange();
604 EV_SET(ev, sep->se_fd, EVFILT_READ,
605 EV_DELETE, 0, 0, 0);
606 }
607 if (pid == 0) {
608 size_t n;
609
610 for (n = 0; n < A_CNT(my_signals); n++)
611 (void) signal(my_signals[n], SIG_DFL);
612 if (debug)
613 setsid();
614 }
615 }
616 if (pid == 0) {
617 run_service(ctrl, sep, dofork);
618 if (dofork)
619 exit(0);
620 }
621 if (!sep->se_wait && sep->se_socktype == SOCK_STREAM)
622 close(ctrl);
623 }
624
625 static void
626 run_service(int ctrl, struct servtab *sep, int didfork)
627 {
628 struct passwd *pwd;
629 struct group *grp = NULL; /* XXX gcc */
630 char buf[NI_MAXSERV];
631 struct servtab *s;
632 #ifdef LIBWRAP
633 char abuf[BUFSIZ];
634 struct request_info req;
635 int denied;
636 char *service = NULL; /* XXX gcc */
637 #endif
638
639 #ifdef LIBWRAP
640 #ifndef LIBWRAP_INTERNAL
641 if (sep->se_bi == 0)
642 #endif
643 if (!sep->se_wait && sep->se_socktype == SOCK_STREAM) {
644 request_init(&req, RQ_DAEMON, sep->se_argv[0] ?
645 sep->se_argv[0] : sep->se_service, RQ_FILE, ctrl, NULL);
646 fromhost(&req);
647 denied = !hosts_access(&req);
648 if (denied || lflag) {
649 if (getnameinfo(&sep->se_ctrladdr,
650 (socklen_t)sep->se_ctrladdr.sa_len, NULL, 0,
651 buf, sizeof(buf), 0) != 0) {
652 /* shouldn't happen */
653 (void)snprintf(buf, sizeof buf, "%d",
654 ntohs(sep->se_ctrladdr_in.sin_port));
655 }
656 service = buf;
657 if (req.client->sin) {
658 sockaddr_snprintf(abuf, sizeof(abuf), "%a",
659 req.client->sin);
660 } else {
661 strcpy(abuf, "(null)");
662 }
663 }
664 if (denied) {
665 syslog(deny_severity,
666 "refused connection from %.500s(%s), service %s (%s)",
667 eval_client(&req), abuf, service, sep->se_proto);
668 goto reject;
669 }
670 if (lflag) {
671 syslog(allow_severity,
672 "connection from %.500s(%s), service %s (%s)",
673 eval_client(&req), abuf, service, sep->se_proto);
674 }
675 }
676 #endif /* LIBWRAP */
677
678 if (sep->se_bi) {
679 if (didfork) {
680 for (s = servtab; s; s = s->se_next)
681 if (s->se_fd != -1 && s->se_fd != ctrl) {
682 close(s->se_fd);
683 s->se_fd = -1;
684 }
685 }
686 (*sep->se_bi->bi_fn)(ctrl, sep);
687 } else {
688 if ((pwd = getpwnam(sep->se_user)) == NULL) {
689 syslog(LOG_ERR, "%s/%s: %s: No such user",
690 sep->se_service, sep->se_proto, sep->se_user);
691 goto reject;
692 }
693 if (sep->se_group &&
694 (grp = getgrnam(sep->se_group)) == NULL) {
695 syslog(LOG_ERR, "%s/%s: %s: No such group",
696 sep->se_service, sep->se_proto, sep->se_group);
697 goto reject;
698 }
699 if (pwd->pw_uid) {
700 if (sep->se_group)
701 pwd->pw_gid = grp->gr_gid;
702 if (setgid(pwd->pw_gid) < 0) {
703 syslog(LOG_ERR,
704 "%s/%s: can't set gid %d: %m", sep->se_service,
705 sep->se_proto, pwd->pw_gid);
706 goto reject;
707 }
708 (void) initgroups(pwd->pw_name,
709 pwd->pw_gid);
710 if (setuid(pwd->pw_uid) < 0) {
711 syslog(LOG_ERR,
712 "%s/%s: can't set uid %d: %m", sep->se_service,
713 sep->se_proto, pwd->pw_uid);
714 goto reject;
715 }
716 } else if (sep->se_group) {
717 (void) setgid((gid_t)grp->gr_gid);
718 }
719 if (debug)
720 fprintf(stderr, "%d execl %s\n",
721 getpid(), sep->se_server);
722 /* Set our control descriptor to not close-on-exec... */
723 if (fcntl(ctrl, F_SETFD, 0) < 0)
724 syslog(LOG_ERR, "fcntl (%d, F_SETFD, 0): %m", ctrl);
725 /* ...and dup it to stdin, stdout, and stderr. */
726 if (ctrl != 0) {
727 dup2(ctrl, 0);
728 close(ctrl);
729 ctrl = 0;
730 }
731 dup2(0, 1);
732 dup2(0, 2);
733 if (rlim_ofile.rlim_cur != rlim_ofile_cur &&
734 setrlimit(RLIMIT_NOFILE, &rlim_ofile) < 0)
735 syslog(LOG_ERR, "setrlimit: %m");
736 execv(sep->se_server, sep->se_argv);
737 syslog(LOG_ERR, "cannot execute %s: %m", sep->se_server);
738 reject:
739 if (sep->se_socktype != SOCK_STREAM)
740 recv(ctrl, buf, sizeof (buf), 0);
741 _exit(1);
742 }
743 }
744
745 static void
746 reapchild(void)
747 {
748 int status;
749 pid_t pid;
750 struct servtab *sep;
751
752 for (;;) {
753 pid = wait3(&status, WNOHANG, NULL);
754 if (pid <= 0)
755 break;
756 if (debug)
757 (void) fprintf(stderr, "%d reaped, status %#x\n",
758 pid, status);
759 for (sep = servtab; sep != NULL; sep = sep->se_next)
760 if (sep->se_wait == pid) {
761 struct kevent *ev;
762
763 if (WIFEXITED(status) && WEXITSTATUS(status))
764 syslog(LOG_WARNING,
765 "%s: exit status 0x%x",
766 sep->se_server, WEXITSTATUS(status));
767 else if (WIFSIGNALED(status))
768 syslog(LOG_WARNING,
769 "%s: exit signal 0x%x",
770 sep->se_server, WTERMSIG(status));
771 sep->se_wait = 1;
772 ev = allocchange();
773 EV_SET(ev, sep->se_fd, EVFILT_READ,
774 EV_ADD | EV_ENABLE, 0, 0, (intptr_t)sep);
775 if (debug)
776 fprintf(stderr, "restored %s, fd %d\n",
777 sep->se_service, sep->se_fd);
778 }
779 }
780 }
781
782 static void
783 config(void)
784 {
785 struct servtab *sep, *cp, **sepp;
786 size_t n;
787
788 if (!setconfig()) {
789 syslog(LOG_ERR, "%s: %m", CONFIG);
790 return;
791 }
792 for (sep = servtab; sep != NULL; sep = sep->se_next)
793 sep->se_checked = 0;
794 while ((cp = getconfigent()) != NULL) {
795 for (sep = servtab; sep != NULL; sep = sep->se_next)
796 if (strcmp(sep->se_service, cp->se_service) == 0 &&
797 strcmp(sep->se_hostaddr, cp->se_hostaddr) == 0 &&
798 strcmp(sep->se_proto, cp->se_proto) == 0 &&
799 ISMUX(sep) == ISMUX(cp))
800 break;
801 if (sep != NULL) {
802 int i;
803
804 #define SWAP(type, a, b) {type c = a; a = b; b = c;}
805
806 /*
807 * sep->se_wait may be holding the pid of a daemon
808 * that we're waiting for. If so, don't overwrite
809 * it unless the config file explicitly says don't
810 * wait.
811 */
812 if (cp->se_bi == 0 &&
813 (sep->se_wait == 1 || cp->se_wait == 0))
814 sep->se_wait = cp->se_wait;
815 SWAP(char *, sep->se_user, cp->se_user);
816 SWAP(char *, sep->se_group, cp->se_group);
817 SWAP(char *, sep->se_server, cp->se_server);
818 for (i = 0; i < MAXARGV; i++)
819 SWAP(char *, sep->se_argv[i], cp->se_argv[i]);
820 #ifdef IPSEC
821 SWAP(char *, sep->se_policy, cp->se_policy);
822 #endif
823 SWAP(int, cp->se_type, sep->se_type);
824 SWAP(int, cp->se_max, sep->se_max);
825 #undef SWAP
826 if (isrpcservice(sep))
827 unregister_rpc(sep);
828 sep->se_rpcversl = cp->se_rpcversl;
829 sep->se_rpcversh = cp->se_rpcversh;
830 freeconfig(cp);
831 if (debug)
832 print_service("REDO", sep);
833 } else {
834 sep = enter(cp);
835 if (debug)
836 print_service("ADD ", sep);
837 }
838 sep->se_checked = 1;
839
840 switch (sep->se_family) {
841 case AF_LOCAL:
842 if (sep->se_fd != -1)
843 break;
844 n = strlen(sep->se_service);
845 if (n > sizeof(sep->se_ctrladdr_un.sun_path)) {
846 syslog(LOG_ERR, "%s: address too long",
847 sep->se_service);
848 sep->se_checked = 0;
849 continue;
850 }
851 (void)unlink(sep->se_service);
852 strncpy(sep->se_ctrladdr_un.sun_path,
853 sep->se_service, n);
854 sep->se_ctrladdr_un.sun_family = AF_LOCAL;
855 sep->se_ctrladdr_size = (int)(n +
856 sizeof(sep->se_ctrladdr_un) -
857 sizeof(sep->se_ctrladdr_un.sun_path));
858 if (!ISMUX(sep))
859 setup(sep);
860 break;
861 case AF_INET:
862 #ifdef INET6
863 case AF_INET6:
864 #endif
865 {
866 struct addrinfo hints, *res;
867 char *host;
868 const char *port;
869 int error;
870 int s;
871
872 /* check if the family is supported */
873 s = socket(sep->se_family, SOCK_DGRAM, 0);
874 if (s < 0) {
875 syslog(LOG_WARNING,
876 "%s/%s: %s: the address family is not "
877 "supported by the kernel",
878 sep->se_service, sep->se_proto,
879 sep->se_hostaddr);
880 sep->se_checked = 0;
881 continue;
882 }
883 close(s);
884
885 memset(&hints, 0, sizeof(hints));
886 hints.ai_family = sep->se_family;
887 hints.ai_socktype = sep->se_socktype;
888 hints.ai_flags = AI_PASSIVE;
889 if (!strcmp(sep->se_hostaddr, "*"))
890 host = NULL;
891 else
892 host = sep->se_hostaddr;
893 if (isrpcservice(sep) || ISMUX(sep))
894 port = "0";
895 else
896 port = sep->se_service;
897 error = getaddrinfo(host, port, &hints, &res);
898 if (error) {
899 if (error == EAI_SERVICE) {
900 /* gai_strerror not friendly enough */
901 syslog(LOG_WARNING, "%s/%s: "
902 "unknown service",
903 sep->se_service, sep->se_proto);
904 } else {
905 syslog(LOG_ERR, "%s/%s: %s: %s",
906 sep->se_service, sep->se_proto,
907 sep->se_hostaddr,
908 gai_strerror(error));
909 }
910 sep->se_checked = 0;
911 continue;
912 }
913 if (res->ai_next) {
914 syslog(LOG_ERR,
915 "%s/%s: %s: resolved to multiple addr",
916 sep->se_service, sep->se_proto,
917 sep->se_hostaddr);
918 sep->se_checked = 0;
919 freeaddrinfo(res);
920 continue;
921 }
922 memcpy(&sep->se_ctrladdr, res->ai_addr,
923 res->ai_addrlen);
924 if (ISMUX(sep)) {
925 sep->se_fd = -1;
926 freeaddrinfo(res);
927 continue;
928 }
929 sep->se_ctrladdr_size = res->ai_addrlen;
930 freeaddrinfo(res);
931 #ifdef RPC
932 if (isrpcservice(sep)) {
933 struct rpcent *rp;
934
935 sep->se_rpcprog = atoi(sep->se_service);
936 if (sep->se_rpcprog == 0) {
937 rp = getrpcbyname(sep->se_service);
938 if (rp == 0) {
939 syslog(LOG_ERR,
940 "%s/%s: unknown service",
941 sep->se_service,
942 sep->se_proto);
943 sep->se_checked = 0;
944 continue;
945 }
946 sep->se_rpcprog = rp->r_number;
947 }
948 if (sep->se_fd == -1 && !ISMUX(sep))
949 setup(sep);
950 if (sep->se_fd != -1)
951 register_rpc(sep);
952 } else
953 #endif
954 {
955 if (sep->se_fd >= 0)
956 close_sep(sep);
957 if (sep->se_fd == -1 && !ISMUX(sep))
958 setup(sep);
959 }
960 }
961 }
962 }
963 endconfig();
964 /*
965 * Purge anything not looked at above.
966 */
967 sepp = &servtab;
968 while ((sep = *sepp) != NULL) {
969 if (sep->se_checked) {
970 sepp = &sep->se_next;
971 continue;
972 }
973 *sepp = sep->se_next;
974 if (sep->se_fd >= 0)
975 close_sep(sep);
976 if (isrpcservice(sep))
977 unregister_rpc(sep);
978 if (sep->se_family == AF_LOCAL)
979 (void)unlink(sep->se_service);
980 if (debug)
981 print_service("FREE", sep);
982 freeconfig(sep);
983 free(sep);
984 }
985 }
986
987 static void
988 retry(void)
989 {
990 struct servtab *sep;
991
992 timingout = 0;
993 for (sep = servtab; sep != NULL; sep = sep->se_next) {
994 if (sep->se_fd == -1 && !ISMUX(sep)) {
995 switch (sep->se_family) {
996 case AF_LOCAL:
997 case AF_INET:
998 #ifdef INET6
999 case AF_INET6:
1000 #endif
1001 setup(sep);
1002 if (sep->se_fd >= 0 && isrpcservice(sep))
1003 register_rpc(sep);
1004 break;
1005 }
1006 }
1007 }
1008 }
1009
1010 static void
1011 goaway(void)
1012 {
1013 struct servtab *sep;
1014
1015 for (sep = servtab; sep != NULL; sep = sep->se_next) {
1016 if (sep->se_fd == -1)
1017 continue;
1018
1019 switch (sep->se_family) {
1020 case AF_LOCAL:
1021 (void)unlink(sep->se_service);
1022 break;
1023 case AF_INET:
1024 #ifdef INET6
1025 case AF_INET6:
1026 #endif
1027 if (sep->se_wait == 1 && isrpcservice(sep))
1028 unregister_rpc(sep);
1029 break;
1030 }
1031 (void)close(sep->se_fd);
1032 sep->se_fd = -1;
1033 }
1034 exit(0);
1035 }
1036
1037 static void
1038 setup(struct servtab *sep)
1039 {
1040 int on = 1;
1041 #ifdef INET6
1042 int off = 0;
1043 #endif
1044 struct kevent *ev;
1045
1046 if ((sep->se_fd = socket(sep->se_family, sep->se_socktype, 0)) < 0) {
1047 if (debug)
1048 fprintf(stderr, "socket failed on %s/%s: %s\n",
1049 sep->se_service, sep->se_proto, strerror(errno));
1050 syslog(LOG_ERR, "%s/%s: socket: %m",
1051 sep->se_service, sep->se_proto);
1052 return;
1053 }
1054 /* Set all listening sockets to close-on-exec. */
1055 if (fcntl(sep->se_fd, F_SETFD, FD_CLOEXEC) < 0) {
1056 syslog(LOG_ERR, "%s/%s: fcntl(F_SETFD, FD_CLOEXEC): %m",
1057 sep->se_service, sep->se_proto);
1058 close(sep->se_fd);
1059 sep->se_fd = -1;
1060 return;
1061 }
1062
1063 #define turnon(fd, opt) \
1064 setsockopt(fd, SOL_SOCKET, opt, &on, (socklen_t)sizeof(on))
1065 if (strcmp(sep->se_proto, "tcp") == 0 && (options & SO_DEBUG) &&
1066 turnon(sep->se_fd, SO_DEBUG) < 0)
1067 syslog(LOG_ERR, "setsockopt (SO_DEBUG): %m");
1068 if (turnon(sep->se_fd, SO_REUSEADDR) < 0)
1069 syslog(LOG_ERR, "setsockopt (SO_REUSEADDR): %m");
1070 #undef turnon
1071
1072 /* Set the socket buffer sizes, if specified. */
1073 if (sep->se_sndbuf != 0 && setsockopt(sep->se_fd, SOL_SOCKET,
1074 SO_SNDBUF, &sep->se_sndbuf, (socklen_t)sizeof(sep->se_sndbuf)) < 0)
1075 syslog(LOG_ERR, "setsockopt (SO_SNDBUF %d): %m",
1076 sep->se_sndbuf);
1077 if (sep->se_rcvbuf != 0 && setsockopt(sep->se_fd, SOL_SOCKET,
1078 SO_RCVBUF, &sep->se_rcvbuf, (socklen_t)sizeof(sep->se_rcvbuf)) < 0)
1079 syslog(LOG_ERR, "setsockopt (SO_RCVBUF %d): %m",
1080 sep->se_rcvbuf);
1081 #ifdef INET6
1082 if (sep->se_family == AF_INET6) {
1083 int *v;
1084 v = (sep->se_type == FAITH_TYPE) ? &on : &off;
1085 if (setsockopt(sep->se_fd, IPPROTO_IPV6, IPV6_FAITH,
1086 v, (socklen_t)sizeof(*v)) < 0)
1087 syslog(LOG_ERR, "setsockopt (IPV6_FAITH): %m");
1088 }
1089 #endif
1090 #ifdef IPSEC
1091 if (ipsecsetup(sep->se_family, sep->se_fd, sep->se_policy) < 0 &&
1092 sep->se_policy) {
1093 syslog(LOG_ERR, "%s/%s: ipsec setup failed",
1094 sep->se_service, sep->se_proto);
1095 (void)close(sep->se_fd);
1096 sep->se_fd = -1;
1097 return;
1098 }
1099 #endif
1100
1101 if (bind(sep->se_fd, &sep->se_ctrladdr,
1102 (socklen_t)sep->se_ctrladdr_size) < 0) {
1103 if (debug)
1104 fprintf(stderr, "bind failed on %s/%s: %s\n",
1105 sep->se_service, sep->se_proto, strerror(errno));
1106 syslog(LOG_ERR, "%s/%s: bind: %m",
1107 sep->se_service, sep->se_proto);
1108 (void) close(sep->se_fd);
1109 sep->se_fd = -1;
1110 if (!timingout) {
1111 timingout = 1;
1112 alarm(RETRYTIME);
1113 }
1114 return;
1115 }
1116 if (sep->se_socktype == SOCK_STREAM)
1117 listen(sep->se_fd, 10);
1118
1119 /* Set the accept filter, if specified. To be done after listen.*/
1120 if (sep->se_accf.af_name[0] != 0 && setsockopt(sep->se_fd, SOL_SOCKET,
1121 SO_ACCEPTFILTER, &sep->se_accf,
1122 (socklen_t)sizeof(sep->se_accf)) < 0)
1123 syslog(LOG_ERR, "setsockopt(SO_ACCEPTFILTER %s): %m",
1124 sep->se_accf.af_name);
1125
1126 ev = allocchange();
1127 EV_SET(ev, sep->se_fd, EVFILT_READ, EV_ADD | EV_ENABLE, 0, 0,
1128 (intptr_t)sep);
1129 if (sep->se_fd > maxsock) {
1130 maxsock = sep->se_fd;
1131 if (maxsock > (int)(rlim_ofile_cur - FD_MARGIN))
1132 bump_nofile();
1133 }
1134 if (debug)
1135 fprintf(stderr, "registered %s on %d\n",
1136 sep->se_server, sep->se_fd);
1137 }
1138
1139 /*
1140 * Finish with a service and its socket.
1141 */
1142 static void
1143 close_sep(struct servtab *sep)
1144 {
1145 if (sep->se_fd >= 0) {
1146 (void) close(sep->se_fd);
1147 sep->se_fd = -1;
1148 }
1149 sep->se_count = 0;
1150 }
1151
1152 static void
1153 register_rpc(struct servtab *sep)
1154 {
1155 #ifdef RPC
1156 struct netbuf nbuf;
1157 struct sockaddr_storage ss;
1158 struct netconfig *nconf;
1159 socklen_t socklen;
1160 int n;
1161
1162 if ((nconf = getnetconfigent(sep->se_proto+4)) == NULL) {
1163 syslog(LOG_ERR, "%s: getnetconfigent failed",
1164 sep->se_proto);
1165 return;
1166 }
1167 socklen = sizeof ss;
1168 if (getsockname(sep->se_fd, (struct sockaddr *)(void *)&ss, &socklen) < 0) {
1169 syslog(LOG_ERR, "%s/%s: getsockname: %m",
1170 sep->se_service, sep->se_proto);
1171 return;
1172 }
1173
1174 nbuf.buf = &ss;
1175 nbuf.len = ss.ss_len;
1176 nbuf.maxlen = sizeof (struct sockaddr_storage);
1177 for (n = sep->se_rpcversl; n <= sep->se_rpcversh; n++) {
1178 if (debug)
1179 fprintf(stderr, "rpcb_set: %u %d %s %s\n",
1180 sep->se_rpcprog, n, nconf->nc_netid,
1181 taddr2uaddr(nconf, &nbuf));
1182 (void)rpcb_unset((unsigned int)sep->se_rpcprog, (unsigned int)n, nconf);
1183 if (!rpcb_set((unsigned int)sep->se_rpcprog, (unsigned int)n, nconf, &nbuf))
1184 syslog(LOG_ERR, "rpcb_set: %u %d %s %s%s",
1185 sep->se_rpcprog, n, nconf->nc_netid,
1186 taddr2uaddr(nconf, &nbuf), clnt_spcreateerror(""));
1187 }
1188 #endif /* RPC */
1189 }
1190
1191 static void
1192 unregister_rpc(struct servtab *sep)
1193 {
1194 #ifdef RPC
1195 int n;
1196 struct netconfig *nconf;
1197
1198 if ((nconf = getnetconfigent(sep->se_proto+4)) == NULL) {
1199 syslog(LOG_ERR, "%s: getnetconfigent failed",
1200 sep->se_proto);
1201 return;
1202 }
1203
1204 for (n = sep->se_rpcversl; n <= sep->se_rpcversh; n++) {
1205 if (debug)
1206 fprintf(stderr, "rpcb_unset(%u, %d, %s)\n",
1207 sep->se_rpcprog, n, nconf->nc_netid);
1208 if (!rpcb_unset((unsigned int)sep->se_rpcprog, (unsigned int)n, nconf))
1209 syslog(LOG_ERR, "rpcb_unset(%u, %d, %s) failed\n",
1210 sep->se_rpcprog, n, nconf->nc_netid);
1211 }
1212 #endif /* RPC */
1213 }
1214
1215
1216 static struct servtab *
1217 enter(struct servtab *cp)
1218 {
1219 struct servtab *sep;
1220
1221 sep = malloc(sizeof (*sep));
1222 if (sep == NULL) {
1223 syslog(LOG_ERR, "Out of memory.");
1224 exit(1);
1225 }
1226 *sep = *cp;
1227 sep->se_fd = -1;
1228 sep->se_rpcprog = -1;
1229 sep->se_next = servtab;
1230 servtab = sep;
1231 return (sep);
1232 }
1233
1234 FILE *fconfig = NULL;
1235 struct servtab serv;
1236 char line[LINE_MAX];
1237 char *defhost;
1238 #ifdef IPSEC
1239 static char *policy = NULL;
1240 #endif
1241
1242 static int
1243 setconfig(void)
1244 {
1245 if (defhost)
1246 free(defhost);
1247 defhost = newstr("*");
1248 #ifdef IPSEC
1249 if (policy)
1250 free(policy);
1251 policy = NULL;
1252 #endif
1253 if (fconfig != NULL) {
1254 fseek(fconfig, 0L, SEEK_SET);
1255 return (1);
1256 }
1257 fconfig = fopen(CONFIG, "r");
1258 return (fconfig != NULL);
1259 }
1260
1261 static void
1262 endconfig(void)
1263 {
1264 if (fconfig != NULL) {
1265 (void) fclose(fconfig);
1266 fconfig = NULL;
1267 }
1268 if (defhost != NULL) {
1269 free(defhost);
1270 defhost = NULL;
1271 }
1272 }
1273
1274 static struct servtab *
1275 getconfigent(void)
1276 {
1277 struct servtab *sep = &serv;
1278 int argc, val;
1279 char *cp, *cp0, *arg, *buf0, *buf1, *sz0, *sz1;
1280 static char TCPMUX_TOKEN[] = "tcpmux/";
1281 #define MUX_LEN (sizeof(TCPMUX_TOKEN)-1)
1282 char *hostdelim;
1283
1284 more:
1285 while ((cp = nextline(fconfig)) != NULL) {
1286 #ifdef IPSEC
1287 /* lines starting with #@ is not a comment, but the policy */
1288 if (cp[0] == '#' && cp[1] == '@') {
1289 char *p;
1290 for (p = cp + 2; p && *p && isspace((unsigned char)*p); p++)
1291 ;
1292 if (*p == '\0') {
1293 if (policy)
1294 free(policy);
1295 policy = NULL;
1296 } else {
1297 if (ipsecsetup_test(p) < 0) {
1298 syslog(LOG_ERR,
1299 "%s: invalid ipsec policy \"%s\"",
1300 CONFIG, p);
1301 exit(1);
1302 } else {
1303 if (policy)
1304 free(policy);
1305 policy = newstr(p);
1306 }
1307 }
1308 }
1309 #endif
1310 if (*cp == '#' || *cp == '\0')
1311 continue;
1312 break;
1313 }
1314 if (cp == NULL)
1315 return (NULL);
1316 /*
1317 * clear the static buffer, since some fields (se_ctrladdr,
1318 * for example) don't get initialized here.
1319 */
1320 memset(sep, 0, sizeof *sep);
1321 arg = skip(&cp);
1322 if (cp == NULL) {
1323 /* got an empty line containing just blanks/tabs. */
1324 goto more;
1325 }
1326 /* Check for a host name. */
1327 hostdelim = strrchr(arg, ':');
1328 if (hostdelim) {
1329 *hostdelim = '\0';
1330 if (arg[0] == '[' && hostdelim > arg && hostdelim[-1] == ']') {
1331 hostdelim[-1] = '\0';
1332 sep->se_hostaddr = newstr(arg + 1);
1333 } else
1334 sep->se_hostaddr = newstr(arg);
1335 arg = hostdelim + 1;
1336 /*
1337 * If the line is of the form `host:', then just change the
1338 * default host for the following lines.
1339 */
1340 if (*arg == '\0') {
1341 arg = skip(&cp);
1342 if (cp == NULL) {
1343 free(defhost);
1344 defhost = sep->se_hostaddr;
1345 goto more;
1346 }
1347 }
1348 } else
1349 sep->se_hostaddr = newstr(defhost);
1350 if (strncmp(arg, TCPMUX_TOKEN, MUX_LEN) == 0) {
1351 char *c = arg + MUX_LEN;
1352 if (*c == '+') {
1353 sep->se_type = MUXPLUS_TYPE;
1354 c++;
1355 } else
1356 sep->se_type = MUX_TYPE;
1357 sep->se_service = newstr(c);
1358 } else {
1359 sep->se_service = newstr(arg);
1360 sep->se_type = NORM_TYPE;
1361 }
1362
1363 arg = sskip(&cp);
1364 if (strncmp(arg, "stream", sizeof("stream") - 1) == 0) {
1365 char *accf, *accf_arg;
1366
1367 sep->se_socktype = SOCK_STREAM;
1368
1369 /* one and only one accept filter */
1370 accf = index(arg, ':');
1371 if (accf) {
1372 if (accf != rindex(arg, ':') || /* more than one */
1373 *(accf + 1) == '\0') { /* nothing beyond */
1374 sep->se_socktype = -1;
1375 } else {
1376 accf++; /* skip delimiter */
1377 strncpy(sep->se_accf.af_name, accf,
1378 sizeof(sep->se_accf.af_name));
1379 accf_arg = index(accf, ',');
1380 if (accf_arg) { /* zero or one arg, no more */
1381 if ((rindex(accf, ',') != accf_arg)) {
1382 sep->se_socktype = -1;
1383 } else {
1384 accf_arg++;
1385 strncpy(sep->se_accf.af_arg,
1386 accf_arg,
1387 sizeof(sep->se_accf.af_arg));
1388 }
1389 }
1390 }
1391 }
1392 }
1393
1394 else if (strcmp(arg, "dgram") == 0)
1395 sep->se_socktype = SOCK_DGRAM;
1396 else if (strcmp(arg, "rdm") == 0)
1397 sep->se_socktype = SOCK_RDM;
1398 else if (strcmp(arg, "seqpacket") == 0)
1399 sep->se_socktype = SOCK_SEQPACKET;
1400 else if (strcmp(arg, "raw") == 0)
1401 sep->se_socktype = SOCK_RAW;
1402 else
1403 sep->se_socktype = -1;
1404
1405 arg = sskip(&cp);
1406 if (sep->se_type == NORM_TYPE &&
1407 strncmp(arg, "faith/", strlen("faith/")) == 0) {
1408 arg += strlen("faith/");
1409 sep->se_type = FAITH_TYPE;
1410 }
1411 sep->se_proto = newstr(arg);
1412
1413 #define MALFORMED(arg) \
1414 do { \
1415 syslog(LOG_ERR, "%s: malformed buffer size option `%s'", \
1416 sep->se_service, (arg)); \
1417 goto more; \
1418 /*NOTREACHED*/ \
1419 } while (/*CONSTCOND*/0)
1420
1421 #define GETVAL(arg) \
1422 do { \
1423 if (!isdigit((unsigned char)*(arg))) \
1424 MALFORMED(arg); \
1425 val = (int)strtol((arg), &cp0, 10); \
1426 if (cp0 != NULL) { \
1427 if (cp0[1] != '\0') \
1428 MALFORMED((arg)); \
1429 if (cp0[0] == 'k') \
1430 val *= 1024; \
1431 if (cp0[0] == 'm') \
1432 val *= 1024 * 1024; \
1433 } \
1434 if (val < 1) { \
1435 syslog(LOG_ERR, "%s: invalid buffer size `%s'", \
1436 sep->se_service, (arg)); \
1437 goto more; \
1438 } \
1439 /*NOTREACHED*/ \
1440 } while (/*CONSTCOND*/0)
1441
1442 #define ASSIGN(arg) \
1443 do { \
1444 if (strcmp((arg), "sndbuf") == 0) \
1445 sep->se_sndbuf = val; \
1446 else if (strcmp((arg), "rcvbuf") == 0) \
1447 sep->se_rcvbuf = val; \
1448 else \
1449 MALFORMED((arg)); \
1450 } while (/*CONSTCOND*/0)
1451
1452 /*
1453 * Extract the send and receive buffer sizes before parsing
1454 * the protocol.
1455 */
1456 sep->se_sndbuf = sep->se_rcvbuf = 0;
1457 buf0 = buf1 = sz0 = sz1 = NULL;
1458 if ((buf0 = strchr(sep->se_proto, ',')) != NULL) {
1459 /* Not meaningful for Tcpmux services. */
1460 if (ISMUX(sep)) {
1461 syslog(LOG_ERR, "%s: can't specify buffer sizes for "
1462 "tcpmux services", sep->se_service);
1463 goto more;
1464 }
1465
1466 /* Skip the , */
1467 *buf0++ = '\0';
1468
1469 /* Check to see if another socket buffer size was specified. */
1470 if ((buf1 = strchr(buf0, ',')) != NULL) {
1471 /* Skip the , */
1472 *buf1++ = '\0';
1473
1474 /* Make sure a 3rd one wasn't specified. */
1475 if (strchr(buf1, ',') != NULL) {
1476 syslog(LOG_ERR, "%s: too many buffer sizes",
1477 sep->se_service);
1478 goto more;
1479 }
1480
1481 /* Locate the size. */
1482 if ((sz1 = strchr(buf1, '=')) == NULL)
1483 MALFORMED(buf1);
1484
1485 /* Skip the = */
1486 *sz1++ = '\0';
1487 }
1488
1489 /* Locate the size. */
1490 if ((sz0 = strchr(buf0, '=')) == NULL)
1491 MALFORMED(buf0);
1492
1493 /* Skip the = */
1494 *sz0++ = '\0';
1495
1496 GETVAL(sz0);
1497 ASSIGN(buf0);
1498
1499 if (buf1 != NULL) {
1500 GETVAL(sz1);
1501 ASSIGN(buf1);
1502 }
1503 }
1504
1505 #undef ASSIGN
1506 #undef GETVAL
1507 #undef MALFORMED
1508
1509 if (strcmp(sep->se_proto, "unix") == 0) {
1510 sep->se_family = AF_LOCAL;
1511 } else {
1512 val = (int)strlen(sep->se_proto);
1513 if (!val) {
1514 syslog(LOG_ERR, "%s: invalid protocol specified",
1515 sep->se_service);
1516 goto more;
1517 }
1518 val = sep->se_proto[val - 1];
1519 switch (val) {
1520 case '4': /*tcp4 or udp4*/
1521 sep->se_family = AF_INET;
1522 break;
1523 #ifdef INET6
1524 case '6': /*tcp6 or udp6*/
1525 sep->se_family = AF_INET6;
1526 break;
1527 #endif
1528 default:
1529 sep->se_family = AF_INET; /*will become AF_INET6*/
1530 break;
1531 }
1532 if (strncmp(sep->se_proto, "rpc/", 4) == 0) {
1533 #ifdef RPC
1534 char *cp1, *ccp;
1535 cp1 = strchr(sep->se_service, '/');
1536 if (cp1 == 0) {
1537 syslog(LOG_ERR, "%s: no rpc version",
1538 sep->se_service);
1539 goto more;
1540 }
1541 *cp1++ = '\0';
1542 sep->se_rpcversl = sep->se_rpcversh =
1543 (int)strtol(cp1, &ccp, 0);
1544 if (ccp == cp1) {
1545 badafterall:
1546 syslog(LOG_ERR, "%s/%s: bad rpc version",
1547 sep->se_service, cp1);
1548 goto more;
1549 }
1550 if (*ccp == '-') {
1551 cp1 = ccp + 1;
1552 sep->se_rpcversh = (int)strtol(cp1, &ccp, 0);
1553 if (ccp == cp1)
1554 goto badafterall;
1555 }
1556 #else
1557 syslog(LOG_ERR, "%s: rpc services not suported",
1558 sep->se_service);
1559 goto more;
1560 #endif /* RPC */
1561 }
1562 }
1563 arg = sskip(&cp);
1564 {
1565 char *cp1;
1566 if ((cp1 = strchr(arg, ':')) == NULL)
1567 cp1 = strchr(arg, '.');
1568 if (cp1 != NULL) {
1569 *cp1++ = '\0';
1570 sep->se_max = atoi(cp1);
1571 } else
1572 sep->se_max = TOOMANY;
1573 }
1574 sep->se_wait = strcmp(arg, "wait") == 0;
1575 if (ISMUX(sep)) {
1576 /*
1577 * Silently enforce "nowait" for TCPMUX services since
1578 * they don't have an assigned port to listen on.
1579 */
1580 sep->se_wait = 0;
1581
1582 if (strncmp(sep->se_proto, "tcp", 3)) {
1583 syslog(LOG_ERR,
1584 "%s: bad protocol for tcpmux service %s",
1585 CONFIG, sep->se_service);
1586 goto more;
1587 }
1588 if (sep->se_socktype != SOCK_STREAM) {
1589 syslog(LOG_ERR,
1590 "%s: bad socket type for tcpmux service %s",
1591 CONFIG, sep->se_service);
1592 goto more;
1593 }
1594 }
1595 sep->se_user = newstr(sskip(&cp));
1596 if ((sep->se_group = strchr(sep->se_user, ':')) != NULL)
1597 *sep->se_group++ = '\0';
1598 else if ((sep->se_group = strchr(sep->se_user, '.')) != NULL)
1599 *sep->se_group++ = '\0';
1600
1601 sep->se_server = newstr(sskip(&cp));
1602 if (strcmp(sep->se_server, "internal") == 0) {
1603 struct biltin *bi;
1604
1605 for (bi = biltins; bi->bi_service; bi++)
1606 if (bi->bi_socktype == sep->se_socktype &&
1607 strcmp(bi->bi_service, sep->se_service) == 0)
1608 break;
1609 if (bi->bi_service == 0) {
1610 syslog(LOG_ERR, "internal service %s unknown",
1611 sep->se_service);
1612 goto more;
1613 }
1614 sep->se_bi = bi;
1615 sep->se_wait = bi->bi_wait;
1616 } else
1617 sep->se_bi = NULL;
1618 argc = 0;
1619 for (arg = skip(&cp); cp; arg = skip(&cp)) {
1620 if (argc < MAXARGV)
1621 sep->se_argv[argc++] = newstr(arg);
1622 }
1623 while (argc <= MAXARGV)
1624 sep->se_argv[argc++] = NULL;
1625 #ifdef IPSEC
1626 sep->se_policy = policy ? newstr(policy) : NULL;
1627 #endif
1628 return (sep);
1629 }
1630
1631 static void
1632 freeconfig(struct servtab *cp)
1633 {
1634 int i;
1635
1636 if (cp->se_hostaddr)
1637 free(cp->se_hostaddr);
1638 if (cp->se_service)
1639 free(cp->se_service);
1640 if (cp->se_proto)
1641 free(cp->se_proto);
1642 if (cp->se_user)
1643 free(cp->se_user);
1644 /* Note: se_group is part of the newstr'ed se_user */
1645 if (cp->se_server)
1646 free(cp->se_server);
1647 for (i = 0; i < MAXARGV; i++)
1648 if (cp->se_argv[i])
1649 free(cp->se_argv[i]);
1650 #ifdef IPSEC
1651 if (cp->se_policy)
1652 free(cp->se_policy);
1653 #endif
1654 }
1655
1656
1657 /*
1658 * Safe skip - if skip returns null, log a syntax error in the
1659 * configuration file and exit.
1660 */
1661 static char *
1662 sskip(char **cpp)
1663 {
1664 char *cp;
1665
1666 cp = skip(cpp);
1667 if (cp == NULL) {
1668 syslog(LOG_ERR, "%s: syntax error", CONFIG);
1669 exit(1);
1670 }
1671 return (cp);
1672 }
1673
1674 static char *
1675 skip(char **cpp)
1676 {
1677 char *cp = *cpp;
1678 char *start;
1679 char quote;
1680
1681 if (*cpp == NULL)
1682 return (NULL);
1683
1684 again:
1685 while (*cp == ' ' || *cp == '\t')
1686 cp++;
1687 if (*cp == '\0') {
1688 int c;
1689
1690 c = getc(fconfig);
1691 (void) ungetc(c, fconfig);
1692 if (c == ' ' || c == '\t')
1693 if ((cp = nextline(fconfig)) != NULL)
1694 goto again;
1695 *cpp = NULL;
1696 return (NULL);
1697 }
1698 start = cp;
1699 quote = '\0';
1700 while (*cp && (quote || (*cp != ' ' && *cp != '\t'))) {
1701 if (*cp == '\'' || *cp == '"') {
1702 if (quote && *cp != quote)
1703 cp++;
1704 else {
1705 if (quote)
1706 quote = '\0';
1707 else
1708 quote = *cp;
1709 memmove(cp, cp+1, strlen(cp));
1710 }
1711 } else
1712 cp++;
1713 }
1714 if (*cp != '\0')
1715 *cp++ = '\0';
1716 *cpp = cp;
1717 return (start);
1718 }
1719
1720 static char *
1721 nextline(FILE *fd)
1722 {
1723 char *cp;
1724
1725 if (fgets(line, (int)sizeof(line), fd) == NULL)
1726 return (NULL);
1727 cp = strchr(line, '\n');
1728 if (cp)
1729 *cp = '\0';
1730 return (line);
1731 }
1732
1733 static char *
1734 newstr(const char *cp)
1735 {
1736 char *dp;
1737 if ((dp = strdup((cp != NULL) ? cp : "")) != NULL)
1738 return (dp);
1739 syslog(LOG_ERR, "strdup: %m");
1740 exit(1);
1741 /*NOTREACHED*/
1742 }
1743
1744 static void
1745 inetd_setproctitle(char *a, int s)
1746 {
1747 socklen_t size;
1748 struct sockaddr_storage ss;
1749 char hbuf[NI_MAXHOST];
1750 const char *hp;
1751 struct sockaddr *sa;
1752
1753 size = sizeof(ss);
1754 sa = (struct sockaddr *)(void *)&ss;
1755 if (getpeername(s, sa, &size) == 0) {
1756 if (getnameinfo(sa, size, hbuf, (socklen_t)sizeof(hbuf), NULL,
1757 0, niflags) != 0)
1758 hp = "?";
1759 else
1760 hp = hbuf;
1761 setproctitle("-%s [%s]", a, hp);
1762 } else
1763 setproctitle("-%s", a);
1764 }
1765
1766 static void
1767 bump_nofile(void)
1768 {
1769 #define FD_CHUNK 32
1770 struct rlimit rl;
1771
1772 if (getrlimit(RLIMIT_NOFILE, &rl) < 0) {
1773 syslog(LOG_ERR, "getrlimit: %m");
1774 return;
1775 }
1776 rl.rlim_cur = MIN(rl.rlim_max, rl.rlim_cur + FD_CHUNK);
1777 if (rl.rlim_cur <= rlim_ofile_cur) {
1778 syslog(LOG_ERR,
1779 "bump_nofile: cannot extend file limit, max = %d",
1780 (int)rl.rlim_cur);
1781 return;
1782 }
1783
1784 if (setrlimit(RLIMIT_NOFILE, &rl) < 0) {
1785 syslog(LOG_ERR, "setrlimit: %m");
1786 return;
1787 }
1788
1789 rlim_ofile_cur = rl.rlim_cur;
1790 return;
1791 }
1792
1793 /*
1794 * Internet services provided internally by inetd:
1795 */
1796 #define BUFSIZE 4096
1797
1798 /* ARGSUSED */
1799 static void
1800 echo_stream(int s, struct servtab *sep) /* Echo service -- echo data back */
1801 {
1802 char buffer[BUFSIZE];
1803 ssize_t i;
1804
1805 inetd_setproctitle(sep->se_service, s);
1806 while ((i = read(s, buffer, sizeof(buffer))) > 0 &&
1807 write(s, buffer, (size_t)i) > 0)
1808 ;
1809 }
1810
1811 /* ARGSUSED */
1812 static void
1813 echo_dg(int s, struct servtab *sep) /* Echo service -- echo data back */
1814 {
1815 char buffer[BUFSIZE];
1816 ssize_t i;
1817 socklen_t size;
1818 struct sockaddr_storage ss;
1819 struct sockaddr *sa;
1820
1821 sa = (struct sockaddr *)(void *)&ss;
1822 size = sizeof(ss);
1823 if ((i = recvfrom(s, buffer, sizeof(buffer), 0, sa, &size)) < 0)
1824 return;
1825 if (port_good_dg(sa))
1826 (void) sendto(s, buffer, (size_t)i, 0, sa, size);
1827 }
1828
1829 /* ARGSUSED */
1830 static void
1831 discard_stream(int s, struct servtab *sep) /* Discard service -- ignore data */
1832 {
1833 char buffer[BUFSIZE];
1834
1835 inetd_setproctitle(sep->se_service, s);
1836 while ((errno = 0, read(s, buffer, sizeof(buffer)) > 0) ||
1837 errno == EINTR)
1838 ;
1839 }
1840
1841 /* ARGSUSED */
1842 static void
1843 discard_dg(int s, struct servtab *sep) /* Discard service -- ignore data */
1844
1845 {
1846 char buffer[BUFSIZE];
1847
1848 (void) read(s, buffer, sizeof(buffer));
1849 }
1850
1851 #define LINESIZ 72
1852 char ring[128];
1853 char *endring;
1854
1855 static void
1856 initring(void)
1857 {
1858 int i;
1859
1860 endring = ring;
1861
1862 for (i = 0; i <= 128; ++i)
1863 if (isprint(i))
1864 *endring++ = i;
1865 }
1866
1867 /* ARGSUSED */
1868 static void
1869 chargen_stream(int s,struct servtab *sep) /* Character generator */
1870 {
1871 size_t len;
1872 char *rs, text[LINESIZ+2];
1873
1874 inetd_setproctitle(sep->se_service, s);
1875
1876 if (!endring) {
1877 initring();
1878 rs = ring;
1879 }
1880
1881 text[LINESIZ] = '\r';
1882 text[LINESIZ + 1] = '\n';
1883 for (rs = ring;;) {
1884 if ((len = endring - rs) >= LINESIZ)
1885 memmove(text, rs, LINESIZ);
1886 else {
1887 memmove(text, rs, len);
1888 memmove(text + len, ring, LINESIZ - len);
1889 }
1890 if (++rs == endring)
1891 rs = ring;
1892 if (write(s, text, sizeof(text)) != sizeof(text))
1893 break;
1894 }
1895 }
1896
1897 /* ARGSUSED */
1898 static void
1899 chargen_dg(int s, struct servtab *sep) /* Character generator */
1900 {
1901 struct sockaddr_storage ss;
1902 struct sockaddr *sa;
1903 static char *rs;
1904 size_t len;
1905 socklen_t size;
1906 char text[LINESIZ+2];
1907
1908 if (endring == 0) {
1909 initring();
1910 rs = ring;
1911 }
1912
1913 sa = (struct sockaddr *)(void *)&ss;
1914 size = sizeof(ss);
1915 if (recvfrom(s, text, sizeof(text), 0, sa, &size) < 0)
1916 return;
1917
1918 if (!port_good_dg(sa))
1919 return;
1920
1921 if ((len = endring - rs) >= LINESIZ)
1922 memmove(text, rs, LINESIZ);
1923 else {
1924 memmove(text, rs, len);
1925 memmove(text + len, ring, LINESIZ - len);
1926 }
1927 if (++rs == endring)
1928 rs = ring;
1929 text[LINESIZ] = '\r';
1930 text[LINESIZ + 1] = '\n';
1931 (void) sendto(s, text, sizeof(text), 0, sa, size);
1932 }
1933
1934 /*
1935 * Return a machine readable date and time, in the form of the
1936 * number of seconds since midnight, Jan 1, 1900. Since gettimeofday
1937 * returns the number of seconds since midnight, Jan 1, 1970,
1938 * we must add 2208988800 seconds to this figure to make up for
1939 * some seventy years Bell Labs was asleep.
1940 */
1941
1942 static uint32_t
1943 machtime(void)
1944 {
1945 struct timeval tv;
1946
1947 if (gettimeofday(&tv, NULL) < 0) {
1948 if (debug)
1949 fprintf(stderr, "Unable to get time of day\n");
1950 return (0);
1951 }
1952 #define OFFSET ((uint32_t)25567 * 24*60*60)
1953 return (htonl((uint32_t)(tv.tv_sec + OFFSET)));
1954 #undef OFFSET
1955 }
1956
1957 /* ARGSUSED */
1958 static void
1959 machtime_stream(int s, struct servtab *sep)
1960 {
1961 uint32_t result;
1962
1963 result = machtime();
1964 (void) write(s, &result, sizeof(result));
1965 }
1966
1967 /* ARGSUSED */
1968 void
1969 machtime_dg(int s, struct servtab *sep)
1970 {
1971 uint32_t result;
1972 struct sockaddr_storage ss;
1973 struct sockaddr *sa;
1974 socklen_t size;
1975
1976 sa = (struct sockaddr *)(void *)&ss;
1977 size = sizeof(ss);
1978 if (recvfrom(s, &result, sizeof(result), 0, sa, &size) < 0)
1979 return;
1980 if (!port_good_dg(sa))
1981 return;
1982 result = machtime();
1983 (void)sendto(s, &result, sizeof(result), 0, sa, size);
1984 }
1985
1986 /* ARGSUSED */
1987 static void
1988 daytime_stream(int s,struct servtab *sep)
1989 /* Return human-readable time of day */
1990 {
1991 char buffer[256];
1992 time_t clk;
1993 int len;
1994
1995 clk = time((time_t *) 0);
1996
1997 len = snprintf(buffer, sizeof buffer, "%.24s\r\n", ctime(&clk));
1998 (void) write(s, buffer, len);
1999 }
2000
2001 /* ARGSUSED */
2002 void
2003 daytime_dg(int s, struct servtab *sep)
2004 /* Return human-readable time of day */
2005 {
2006 char buffer[256];
2007 time_t clk;
2008 struct sockaddr_storage ss;
2009 struct sockaddr *sa;
2010 socklen_t size;
2011 int len;
2012
2013 clk = time((time_t *) 0);
2014
2015 sa = (struct sockaddr *)(void *)&ss;
2016 size = sizeof(ss);
2017 if (recvfrom(s, buffer, sizeof(buffer), 0, sa, &size) < 0)
2018 return;
2019 if (!port_good_dg(sa))
2020 return;
2021 len = snprintf(buffer, sizeof buffer, "%.24s\r\n", ctime(&clk));
2022 (void) sendto(s, buffer, len, 0, sa, size);
2023 }
2024
2025 /*
2026 * print_service:
2027 * Dump relevant information to stderr
2028 */
2029 static void
2030 print_service(const char *action, struct servtab *sep)
2031 {
2032
2033 if (isrpcservice(sep))
2034 fprintf(stderr,
2035 "%s: %s rpcprog=%d, rpcvers = %d/%d, proto=%s, wait.max=%d.%d, user:group=%s:%s builtin=%lx server=%s"
2036 #ifdef IPSEC
2037 " policy=\"%s\""
2038 #endif
2039 "\n",
2040 action, sep->se_service,
2041 sep->se_rpcprog, sep->se_rpcversh, sep->se_rpcversl, sep->se_proto,
2042 sep->se_wait, sep->se_max, sep->se_user, sep->se_group,
2043 (long)sep->se_bi, sep->se_server
2044 #ifdef IPSEC
2045 , (sep->se_policy ? sep->se_policy : "")
2046 #endif
2047 );
2048 else
2049 fprintf(stderr,
2050 "%s: %s proto=%s%s, wait.max=%d.%d, user:group=%s:%s builtin=%lx server=%s"
2051 #ifdef IPSEC
2052 " policy=%s"
2053 #endif
2054 "\n",
2055 action, sep->se_service,
2056 sep->se_type == FAITH_TYPE ? "faith/" : "",
2057 sep->se_proto,
2058 sep->se_wait, sep->se_max, sep->se_user, sep->se_group,
2059 (long)sep->se_bi, sep->se_server
2060 #ifdef IPSEC
2061 , (sep->se_policy ? sep->se_policy : "")
2062 #endif
2063 );
2064 }
2065
2066 static void
2067 usage(void)
2068 {
2069 #ifdef LIBWRAP
2070 (void)fprintf(stderr, "usage: %s [-dl] [conf]\n", getprogname());
2071 #else
2072 (void)fprintf(stderr, "usage: %s [-d] [conf]\n", getprogname());
2073 #endif
2074 exit(1);
2075 }
2076
2077
2078 /*
2079 * Based on TCPMUX.C by Mark K. Lottor November 1988
2080 * sri-nic::ps:<mkl>tcpmux.c
2081 */
2082
2083 static int /* # of characters upto \r,\n or \0 */
2084 get_line(int fd, char *buf, int len)
2085 {
2086 int count = 0;
2087 ssize_t n;
2088
2089 do {
2090 n = read(fd, buf, len-count);
2091 if (n == 0)
2092 return (count);
2093 if (n < 0)
2094 return (-1);
2095 while (--n >= 0) {
2096 if (*buf == '\r' || *buf == '\n' || *buf == '\0')
2097 return (count);
2098 count++;
2099 buf++;
2100 }
2101 } while (count < len);
2102 return (count);
2103 }
2104
2105 #define MAX_SERV_LEN (256+2) /* 2 bytes for \r\n */
2106
2107 #define strwrite(fd, buf) (void) write(fd, buf, sizeof(buf)-1)
2108
2109 static void
2110 tcpmux(int ctrl, struct servtab *sep)
2111 {
2112 char service[MAX_SERV_LEN+1];
2113 int len;
2114
2115 /* Get requested service name */
2116 if ((len = get_line(ctrl, service, MAX_SERV_LEN)) < 0) {
2117 strwrite(ctrl, "-Error reading service name\r\n");
2118 goto reject;
2119 }
2120 service[len] = '\0';
2121
2122 if (debug)
2123 fprintf(stderr, "tcpmux: someone wants %s\n", service);
2124
2125 /*
2126 * Help is a required command, and lists available services,
2127 * one per line.
2128 */
2129 if (!strcasecmp(service, "help")) {
2130 strwrite(ctrl, "+Available services:\r\n");
2131 strwrite(ctrl, "help\r\n");
2132 for (sep = servtab; sep != NULL; sep = sep->se_next) {
2133 if (!ISMUX(sep))
2134 continue;
2135 (void)write(ctrl, sep->se_service,
2136 strlen(sep->se_service));
2137 strwrite(ctrl, "\r\n");
2138 }
2139 goto reject;
2140 }
2141
2142 /* Try matching a service in inetd.conf with the request */
2143 for (sep = servtab; sep != NULL; sep = sep->se_next) {
2144 if (!ISMUX(sep))
2145 continue;
2146 if (!strcasecmp(service, sep->se_service)) {
2147 if (ISMUXPLUS(sep))
2148 strwrite(ctrl, "+Go\r\n");
2149 run_service(ctrl, sep, 1 /* forked */);
2150 return;
2151 }
2152 }
2153 strwrite(ctrl, "-Service not available\r\n");
2154 reject:
2155 _exit(1);
2156 }
2157
2158 /*
2159 * check if the address/port where send data to is one of the obvious ports
2160 * that are used for denial of service attacks like two echo ports
2161 * just echoing data between them
2162 */
2163 static int
2164 port_good_dg(struct sockaddr *sa)
2165 {
2166 struct in_addr in;
2167 struct sockaddr_in *sin;
2168 #ifdef INET6
2169 struct in6_addr *in6;
2170 struct sockaddr_in6 *sin6;
2171 #endif
2172 u_int16_t port;
2173 int i;
2174 char hbuf[NI_MAXHOST];
2175
2176 switch (sa->sa_family) {
2177 case AF_INET:
2178 sin = (struct sockaddr_in *)(void *)sa;
2179 in.s_addr = ntohl(sin->sin_addr.s_addr);
2180 port = ntohs(sin->sin_port);
2181 #ifdef INET6
2182 v4chk:
2183 #endif
2184 if (IN_MULTICAST(in.s_addr))
2185 goto bad;
2186 switch ((in.s_addr & 0xff000000) >> 24) {
2187 case 0: case 127: case 255:
2188 goto bad;
2189 }
2190 if (dg_broadcast(&in))
2191 goto bad;
2192 break;
2193 #ifdef INET6
2194 case AF_INET6:
2195 sin6 = (struct sockaddr_in6 *)(void *)sa;
2196 in6 = &sin6->sin6_addr;
2197 port = ntohs(sin6->sin6_port);
2198 if (IN6_IS_ADDR_MULTICAST(in6) || IN6_IS_ADDR_UNSPECIFIED(in6))
2199 goto bad;
2200 if (IN6_IS_ADDR_V4MAPPED(in6) || IN6_IS_ADDR_V4COMPAT(in6)) {
2201 memcpy(&in, &in6->s6_addr[12], sizeof(in));
2202 in.s_addr = ntohl(in.s_addr);
2203 goto v4chk;
2204 }
2205 break;
2206 #endif
2207 default:
2208 /* XXX unsupported af, is it safe to assume it to be safe? */
2209 return (1);
2210 }
2211
2212 for (i = 0; bad_ports[i] != 0; i++) {
2213 if (port == bad_ports[i])
2214 goto bad;
2215 }
2216
2217 return (1);
2218
2219 bad:
2220 if (getnameinfo(sa, sa->sa_len, hbuf, (socklen_t)sizeof(hbuf), NULL, 0,
2221 niflags) != 0)
2222 strlcpy(hbuf, "?", sizeof(hbuf));
2223 syslog(LOG_WARNING,"Possible DoS attack from %s, Port %d",
2224 hbuf, port);
2225 return (0);
2226 }
2227
2228 /* XXX need optimization */
2229 static int
2230 dg_broadcast(struct in_addr *in)
2231 {
2232 struct ifaddrs *ifa, *ifap;
2233 struct sockaddr_in *sin;
2234
2235 if (getifaddrs(&ifap) < 0)
2236 return (0);
2237 for (ifa = ifap; ifa; ifa = ifa->ifa_next) {
2238 if (ifa->ifa_addr->sa_family != AF_INET ||
2239 (ifa->ifa_flags & IFF_BROADCAST) == 0)
2240 continue;
2241 sin = (struct sockaddr_in *)(void *)ifa->ifa_broadaddr;
2242 if (sin->sin_addr.s_addr == in->s_addr) {
2243 freeifaddrs(ifap);
2244 return (1);
2245 }
2246 }
2247 freeifaddrs(ifap);
2248 return (0);
2249 }
2250
2251 static int
2252 my_kevent(const struct kevent *changelist, size_t nchanges,
2253 struct kevent *eventlist, size_t nevents)
2254 {
2255 int result;
2256
2257 while ((result = kevent(kq, changelist, nchanges, eventlist, nevents,
2258 NULL)) < 0)
2259 if (errno != EINTR) {
2260 syslog(LOG_ERR, "kevent: %m");
2261 exit(EXIT_FAILURE);
2262 }
2263
2264 return (result);
2265 }
2266
2267 static struct kevent *
2268 allocchange(void)
2269 {
2270 if (changes == A_CNT(changebuf)) {
2271 (void) my_kevent(changebuf, A_CNT(changebuf), NULL, 0);
2272 changes = 0;
2273 }
2274
2275 return (&changebuf[changes++]);
2276 }
2277