inetd.c revision 1.105 1 /* $NetBSD: inetd.c,v 1.105 2008/05/26 03:41:25 dholland 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\n\
65 The Regents of the University of California. All rights reserved.\n");
66 #if 0
67 static char sccsid[] = "@(#)inetd.c 8.4 (Berkeley) 4/13/94";
68 #else
69 __RCSID("$NetBSD: inetd.c,v 1.105 2008/05/26 03:41:25 dholland 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 stream/dgram/raw/rdm/seqpacket
99 * protocol must be in /etc/protocols
100 * wait/nowait[:max] single-threaded/multi-threaded, max #
101 * user[:group] user/group to run daemon as
102 * server program full path name
103 * server program arguments maximum of MAXARGS (20)
104 *
105 * For RPC services
106 * service name/version must be in /etc/rpc
107 * socket type stream/dgram/raw/rdm/seqpacket
108 * protocol must be in /etc/protocols
109 * wait/nowait[:max] single-threaded/multi-threaded
110 * user[:group] user to run daemon as
111 * server program full path name
112 * server program arguments maximum of MAXARGS (20)
113 *
114 * For non-RPC services, the "service name" can be of the form
115 * hostaddress:servicename, in which case the hostaddress is used
116 * as the host portion of the address to listen on. If hostaddress
117 * consists of a single `*' character, INADDR_ANY is used.
118 *
119 * A line can also consist of just
120 * hostaddress:
121 * where hostaddress is as in the preceding paragraph. Such a line must
122 * have no further fields; the specified hostaddress is remembered and
123 * used for all further lines that have no hostaddress specified,
124 * until the next such line (or EOF). (This is why * is provided to
125 * allow explicit specification of INADDR_ANY.) A line
126 * *:
127 * is implicitly in effect at the beginning of the file.
128 *
129 * The hostaddress specifier may (and often will) contain dots;
130 * the service name must not.
131 *
132 * For RPC services, host-address specifiers are accepted and will
133 * work to some extent; however, because of limitations in the
134 * portmapper interface, it will not work to try to give more than
135 * one line for any given RPC service, even if the host-address
136 * specifiers are different.
137 *
138 * TCP services without official port numbers are handled with the
139 * RFC1078-based tcpmux internal service. Tcpmux listens on port 1 for
140 * requests. When a connection is made from a foreign host, the service
141 * requested is passed to tcpmux, which looks it up in the servtab list
142 * and returns the proper entry for the service. Tcpmux returns a
143 * negative reply if the service doesn't exist, otherwise the invoked
144 * server is expected to return the positive reply if the service type in
145 * inetd.conf file has the prefix "tcpmux/". If the service type has the
146 * prefix "tcpmux/+", tcpmux will return the positive reply for the
147 * process; this is for compatibility with older server code, and also
148 * allows you to invoke programs that use stdin/stdout without putting any
149 * special server code in them. Services that use tcpmux are "nowait"
150 * because they do not have a well-known port and hence cannot listen
151 * for new requests.
152 *
153 * Comment lines are indicated by a `#' in column 1.
154 *
155 * #ifdef IPSEC
156 * Comment lines that start with "#@" denote IPsec policy string, as described
157 * in ipsec_set_policy(3). This will affect all the following items in
158 * inetd.conf(8). To reset the policy, just use "#@" line. By default,
159 * there's no IPsec policy.
160 * #endif
161 */
162
163 /*
164 * Here's the scoop concerning the user:group feature:
165 *
166 * 1) set-group-option off.
167 *
168 * a) user = root: NO setuid() or setgid() is done
169 *
170 * b) other: setuid()
171 * setgid(primary group as found in passwd)
172 * initgroups(name, primary group)
173 *
174 * 2) set-group-option on.
175 *
176 * a) user = root: NO setuid()
177 * setgid(specified group)
178 * NO initgroups()
179 *
180 * b) other: setuid()
181 * setgid(specified group)
182 * initgroups(name, specified group)
183 *
184 */
185
186 #include <sys/param.h>
187 #include <sys/stat.h>
188 #include <sys/ioctl.h>
189 #include <sys/socket.h>
190 #include <sys/un.h>
191 #include <sys/wait.h>
192 #include <sys/time.h>
193 #include <sys/resource.h>
194 #include <sys/event.h>
195
196 #ifndef RLIMIT_NOFILE
197 #define RLIMIT_NOFILE RLIMIT_OFILE
198 #endif
199
200 #ifndef NO_RPC
201 #define RPC
202 #endif
203
204 #include <net/if.h>
205
206 #include <netinet/in.h>
207 #include <arpa/inet.h>
208 #ifdef RPC
209 #include <rpc/rpc.h>
210 #include <rpc/rpcb_clnt.h>
211 #include <netconfig.h>
212 #endif
213
214 #include <ctype.h>
215 #include <errno.h>
216 #include <fcntl.h>
217 #include <grp.h>
218 #include <netdb.h>
219 #include <pwd.h>
220 #include <signal.h>
221 #include <stdio.h>
222 #include <stdlib.h>
223 #include <string.h>
224 #include <syslog.h>
225 #include <unistd.h>
226 #include <util.h>
227 #include <ifaddrs.h>
228
229 #include "pathnames.h"
230
231 #ifdef IPSEC
232 #include <netinet6/ipsec.h>
233 #ifndef IPSEC_POLICY_IPSEC /* no ipsec support on old ipsec */
234 #undef IPSEC
235 #endif
236 #include "ipsec.h"
237 #endif
238
239 #ifdef LIBWRAP
240 # include <tcpd.h>
241 #ifndef LIBWRAP_ALLOW_FACILITY
242 # define LIBWRAP_ALLOW_FACILITY LOG_AUTH
243 #endif
244 #ifndef LIBWRAP_ALLOW_SEVERITY
245 # define LIBWRAP_ALLOW_SEVERITY LOG_INFO
246 #endif
247 #ifndef LIBWRAP_DENY_FACILITY
248 # define LIBWRAP_DENY_FACILITY LOG_AUTH
249 #endif
250 #ifndef LIBWRAP_DENY_SEVERITY
251 # define LIBWRAP_DENY_SEVERITY LOG_WARNING
252 #endif
253 int allow_severity = LIBWRAP_ALLOW_FACILITY|LIBWRAP_ALLOW_SEVERITY;
254 int deny_severity = LIBWRAP_DENY_FACILITY|LIBWRAP_DENY_SEVERITY;
255 #endif
256
257 #define TOOMANY 40 /* don't start more than TOOMANY */
258 #define CNT_INTVL 60 /* servers in CNT_INTVL sec. */
259 #define RETRYTIME (60*10) /* retry after bind or server fail */
260
261 #define A_CNT(a) (sizeof (a) / sizeof (a[0]))
262
263 int debug;
264 #ifdef LIBWRAP
265 int lflag;
266 #endif
267 int maxsock;
268 int kq;
269 int options;
270 int timingout;
271 struct servent *sp;
272 char *curdom;
273 const int niflags = NI_NUMERICHOST | NI_NUMERICSERV;
274
275 #ifndef OPEN_MAX
276 #define OPEN_MAX 64
277 #endif
278
279 /* Reserve some descriptors, 3 stdio + at least: 1 log, 1 conf. file */
280 #define FD_MARGIN (8)
281 rlim_t rlim_ofile_cur = OPEN_MAX;
282
283 #ifdef RLIMIT_NOFILE
284 struct rlimit rlim_ofile;
285 #endif
286
287 struct kevent changebuf[64];
288 size_t changes;
289
290 struct servtab {
291 char *se_hostaddr; /* host address to listen on */
292 char *se_service; /* name of service */
293 int se_socktype; /* type of socket to use */
294 int se_family; /* address family */
295 char *se_proto; /* protocol used */
296 int se_sndbuf; /* sndbuf size */
297 int se_rcvbuf; /* rcvbuf size */
298 int se_rpcprog; /* rpc program number */
299 int se_rpcversl; /* rpc program lowest version */
300 int se_rpcversh; /* rpc program highest version */
301 #define isrpcservice(sep) ((sep)->se_rpcversl != 0)
302 pid_t se_wait; /* single threaded server */
303 short se_checked; /* looked at during merge */
304 char *se_user; /* user name to run as */
305 char *se_group; /* group name to run as */
306 struct biltin *se_bi; /* if built-in, description */
307 char *se_server; /* server program */
308 #define MAXARGV 20
309 char *se_argv[MAXARGV+1]; /* program arguments */
310 #ifdef IPSEC
311 char *se_policy; /* IPsec poilcy string */
312 #endif
313 int se_fd; /* open descriptor */
314 int se_type; /* type */
315 union {
316 struct sockaddr se_un_ctrladdr;
317 struct sockaddr_in se_un_ctrladdr_in;
318 struct sockaddr_in6 se_un_ctrladdr_in6;
319 struct sockaddr_un se_un_ctrladdr_un;
320 } se_un; /* bound address */
321 #define se_ctrladdr se_un.se_un_ctrladdr
322 #define se_ctrladdr_in se_un.se_un_ctrladdr_in
323 #define se_ctrladdr_un se_un.se_un_ctrladdr_un
324 int se_ctrladdr_size;
325 int se_max; /* max # of instances of this service */
326 int se_count; /* number started since se_time */
327 struct timeval se_time; /* start of se_count */
328 #ifdef MULOG
329 int se_log;
330 #define MULOG_RFC931 0x40000000
331 #endif
332 struct servtab *se_next;
333 } *servtab;
334
335 #define NORM_TYPE 0
336 #define MUX_TYPE 1
337 #define MUXPLUS_TYPE 2
338 #define FAITH_TYPE 3
339 #define ISMUX(sep) (((sep)->se_type == MUX_TYPE) || \
340 ((sep)->se_type == MUXPLUS_TYPE))
341 #define ISMUXPLUS(sep) ((sep)->se_type == MUXPLUS_TYPE)
342
343
344 static void chargen_dg(int, struct servtab *);
345 static void chargen_stream(int, struct servtab *);
346 static void close_sep(struct servtab *);
347 static void config(void);
348 static void daytime_dg(int, struct servtab *);
349 static void daytime_stream(int, struct servtab *);
350 static void discard_dg(int, struct servtab *);
351 static void discard_stream(int, struct servtab *);
352 static void echo_dg(int, struct servtab *);
353 static void echo_stream(int, struct servtab *);
354 static void endconfig(void);
355 static struct servtab *enter(struct servtab *);
356 static void freeconfig(struct servtab *);
357 static struct servtab *getconfigent(void);
358 static void goaway(void);
359 static void machtime_dg(int, struct servtab *);
360 static void machtime_stream(int, struct servtab *);
361 static char *newstr(char *);
362 static char *nextline(FILE *);
363 static void print_service(char *, struct servtab *);
364 static void reapchild(void);
365 static void retry(void);
366 static void run_service(int, struct servtab *, int);
367 static int setconfig(void);
368 static void setup(struct servtab *);
369 static char *sskip(char **);
370 static char *skip(char **);
371 static void tcpmux(int, struct servtab *);
372 static void usage(void);
373 static void register_rpc(struct servtab *);
374 static void unregister_rpc(struct servtab *);
375 static void bump_nofile(void);
376 static void inetd_setproctitle(char *, int);
377 static void initring(void);
378 static uint32_t machtime(void);
379 static int port_good_dg(struct sockaddr *);
380 static int dg_broadcast(struct in_addr *);
381 static int my_kevent(const struct kevent *, size_t, struct kevent *,
382 size_t);
383 static struct kevent * allocchange(void);
384 static int getline(int, char *, int);
385 static void spawn(struct servtab *, int);
386 #ifdef MULOG
387 static void dolog(struct servtab *, int);
388 static void timeout(int);
389 static char *rfc931_name(struct sockaddr *, int);
390 #endif
391
392 struct biltin {
393 char *bi_service; /* internally provided service name */
394 int bi_socktype; /* type of socket supported */
395 short bi_fork; /* 1 if should fork before call */
396 short bi_wait; /* 1 if should wait for child */
397 void (*bi_fn)(int, struct servtab *);
398 /* function which performs it */
399 } biltins[] = {
400 /* Echo received data */
401 { "echo", SOCK_STREAM, 1, 0, echo_stream },
402 { "echo", SOCK_DGRAM, 0, 0, echo_dg },
403
404 /* Internet /dev/null */
405 { "discard", SOCK_STREAM, 1, 0, discard_stream },
406 { "discard", SOCK_DGRAM, 0, 0, discard_dg },
407
408 /* Return 32 bit time since 1970 */
409 { "time", SOCK_STREAM, 0, 0, machtime_stream },
410 { "time", SOCK_DGRAM, 0, 0, machtime_dg },
411
412 /* Return human-readable time */
413 { "daytime", SOCK_STREAM, 0, 0, daytime_stream },
414 { "daytime", SOCK_DGRAM, 0, 0, daytime_dg },
415
416 /* Familiar character generator */
417 { "chargen", SOCK_STREAM, 1, 0, chargen_stream },
418 { "chargen", SOCK_DGRAM, 0, 0, chargen_dg },
419
420 { "tcpmux", SOCK_STREAM, 1, 0, tcpmux },
421
422 { NULL }
423 };
424
425 /* list of "bad" ports. I.e. ports that are most obviously used for
426 * "cycling packets" denial of service attacks. See /etc/services.
427 * List must end with port number "0".
428 */
429
430 u_int16_t bad_ports[] = { 7, 9, 13, 19, 37, 0 };
431
432
433 #define NUMINT (sizeof(intab) / sizeof(struct inent))
434 char *CONFIG = _PATH_INETDCONF;
435
436 static int my_signals[] =
437 { SIGALRM, SIGHUP, SIGCHLD, SIGTERM, SIGINT, SIGPIPE };
438
439 int
440 main(int argc, char *argv[])
441 {
442 int ch, n, reload = 1;
443
444 while ((ch = getopt(argc, argv,
445 #ifdef LIBWRAP
446 "dl"
447 #else
448 "d"
449 #endif
450 )) != -1)
451 switch(ch) {
452 case 'd':
453 debug = 1;
454 options |= SO_DEBUG;
455 break;
456 #ifdef LIBWRAP
457 case 'l':
458 lflag = 1;
459 break;
460 #endif
461 case '?':
462 default:
463 usage();
464 }
465 argc -= optind;
466 argv += optind;
467
468 if (argc > 0)
469 CONFIG = argv[0];
470
471 if (!debug)
472 daemon(0, 0);
473 openlog("inetd", LOG_PID | LOG_NOWAIT, LOG_DAEMON);
474 pidfile(NULL);
475
476 kq = kqueue();
477 if (kq < 0) {
478 syslog(LOG_ERR, "kqueue: %m");
479 return (EXIT_FAILURE);
480 }
481
482 #ifdef RLIMIT_NOFILE
483 if (getrlimit(RLIMIT_NOFILE, &rlim_ofile) < 0) {
484 syslog(LOG_ERR, "getrlimit: %m");
485 } else {
486 rlim_ofile_cur = rlim_ofile.rlim_cur;
487 if (rlim_ofile_cur == RLIM_INFINITY) /* ! */
488 rlim_ofile_cur = OPEN_MAX;
489 }
490 #endif
491
492 for (n = 0; n < (int)A_CNT(my_signals); n++) {
493 int signum;
494
495 signum = my_signals[n];
496 if (signum != SIGCHLD)
497 (void) signal(signum, SIG_IGN);
498
499 if (signum != SIGPIPE) {
500 struct kevent *ev;
501
502 ev = allocchange();
503 EV_SET(ev, signum, EVFILT_SIGNAL, EV_ADD | EV_ENABLE,
504 0, 0, 0);
505 }
506 }
507
508 for (;;) {
509 int ctrl;
510 struct kevent eventbuf[64], *ev;
511 struct servtab *sep;
512
513 if (reload) {
514 reload = 0;
515 config();
516 }
517
518 n = my_kevent(changebuf, changes, eventbuf, A_CNT(eventbuf));
519 changes = 0;
520
521 for (ev = eventbuf; n > 0; ev++, n--) {
522 if (ev->filter == EVFILT_SIGNAL) {
523 switch (ev->ident) {
524 case SIGALRM:
525 retry();
526 break;
527 case SIGCHLD:
528 reapchild();
529 break;
530 case SIGTERM:
531 case SIGINT:
532 goaway();
533 break;
534 case SIGHUP:
535 reload = 1;
536 break;
537 }
538 continue;
539 }
540 if (ev->filter != EVFILT_READ)
541 continue;
542 sep = (struct servtab *)ev->udata;
543 /* Paranoia */
544 if ((int)ev->ident != sep->se_fd)
545 continue;
546 if (debug)
547 fprintf(stderr, "someone wants %s\n",
548 sep->se_service);
549 if (!sep->se_wait && sep->se_socktype == SOCK_STREAM) {
550 /* XXX here do the libwrap check-before-accept*/
551 ctrl = accept(sep->se_fd, NULL, NULL);
552 if (debug)
553 fprintf(stderr, "accept, ctrl %d\n",
554 ctrl);
555 if (ctrl < 0) {
556 if (errno != EINTR)
557 syslog(LOG_WARNING,
558 "accept (for %s): %m",
559 sep->se_service);
560 continue;
561 }
562 } else
563 ctrl = sep->se_fd;
564 spawn(sep, ctrl);
565 }
566 }
567 }
568
569 static void
570 spawn(struct servtab *sep, int ctrl)
571 {
572 int dofork;
573 pid_t pid;
574
575 pid = 0;
576 #ifdef LIBWRAP_INTERNAL
577 dofork = 1;
578 #else
579 dofork = (sep->se_bi == 0 || sep->se_bi->bi_fork);
580 #endif
581 if (dofork) {
582 if (sep->se_count++ == 0)
583 (void)gettimeofday(&sep->se_time, NULL);
584 else if (sep->se_count >= sep->se_max) {
585 struct timeval now;
586
587 (void)gettimeofday(&now, NULL);
588 if (now.tv_sec - sep->se_time.tv_sec > CNT_INTVL) {
589 sep->se_time = now;
590 sep->se_count = 1;
591 } else {
592 syslog(LOG_ERR,
593 "%s/%s max spawn rate (%d in %d seconds) "
594 "exceeded; service not started",
595 sep->se_service, sep->se_proto,
596 sep->se_max, CNT_INTVL);
597 if (!sep->se_wait && sep->se_socktype ==
598 SOCK_STREAM)
599 close(ctrl);
600 close_sep(sep);
601 if (!timingout) {
602 timingout = 1;
603 alarm(RETRYTIME);
604 }
605 return;
606 }
607 }
608 pid = fork();
609 if (pid < 0) {
610 syslog(LOG_ERR, "fork: %m");
611 if (!sep->se_wait && sep->se_socktype == SOCK_STREAM)
612 close(ctrl);
613 sleep(1);
614 return;
615 }
616 if (pid != 0 && sep->se_wait) {
617 struct kevent *ev;
618
619 sep->se_wait = pid;
620 ev = allocchange();
621 EV_SET(ev, sep->se_fd, EVFILT_READ,
622 EV_DELETE, 0, 0, 0);
623 }
624 if (pid == 0) {
625 size_t n;
626
627 for (n = 0; n < A_CNT(my_signals); n++)
628 (void) signal(my_signals[n], SIG_DFL);
629 if (debug)
630 setsid();
631 }
632 }
633 if (pid == 0) {
634 run_service(ctrl, sep, dofork);
635 if (dofork)
636 exit(0);
637 }
638 if (!sep->se_wait && sep->se_socktype == SOCK_STREAM)
639 close(ctrl);
640 }
641
642 static void
643 run_service(int ctrl, struct servtab *sep, int didfork)
644 {
645 struct passwd *pwd;
646 struct group *grp = NULL; /* XXX gcc */
647 char buf[NI_MAXSERV];
648 struct servtab *s;
649 #ifdef LIBWRAP
650 struct request_info req;
651 int denied;
652 char *service = NULL; /* XXX gcc */
653 #endif
654
655 #ifdef LIBWRAP
656 #ifndef LIBWRAP_INTERNAL
657 if (sep->se_bi == 0)
658 #endif
659 if (!sep->se_wait && sep->se_socktype == SOCK_STREAM) {
660 request_init(&req, RQ_DAEMON, sep->se_argv[0] ?
661 sep->se_argv[0] : sep->se_service, RQ_FILE, ctrl, NULL);
662 fromhost(&req);
663 denied = !hosts_access(&req);
664 if (denied || lflag) {
665 if (getnameinfo(&sep->se_ctrladdr,
666 sep->se_ctrladdr.sa_len, NULL, 0,
667 buf, sizeof(buf), 0) != 0) {
668 /* shouldn't happen */
669 (void)snprintf(buf, sizeof buf, "%d",
670 ntohs(sep->se_ctrladdr_in.sin_port));
671 }
672 service = buf;
673 }
674 if (denied) {
675 syslog(deny_severity,
676 "refused connection from %.500s, service %s (%s)",
677 eval_client(&req), service, sep->se_proto);
678 goto reject;
679 }
680 if (lflag) {
681 syslog(allow_severity,
682 "connection from %.500s, service %s (%s)",
683 eval_client(&req), service, sep->se_proto);
684 }
685 }
686 #endif /* LIBWRAP */
687
688 if (sep->se_bi) {
689 if (didfork) {
690 for (s = servtab; s; s = s->se_next)
691 if (s->se_fd != -1 && s->se_fd != ctrl)
692 close(s->se_fd);
693 }
694 (*sep->se_bi->bi_fn)(ctrl, sep);
695 } else {
696 if ((pwd = getpwnam(sep->se_user)) == NULL) {
697 syslog(LOG_ERR, "%s/%s: %s: No such user",
698 sep->se_service, sep->se_proto, sep->se_user);
699 goto reject;
700 }
701 if (sep->se_group &&
702 (grp = getgrnam(sep->se_group)) == NULL) {
703 syslog(LOG_ERR, "%s/%s: %s: No such group",
704 sep->se_service, sep->se_proto, sep->se_group);
705 goto reject;
706 }
707 if (pwd->pw_uid) {
708 if (sep->se_group)
709 pwd->pw_gid = grp->gr_gid;
710 if (setgid(pwd->pw_gid) < 0) {
711 syslog(LOG_ERR,
712 "%s/%s: can't set gid %d: %m", sep->se_service,
713 sep->se_proto, pwd->pw_gid);
714 goto reject;
715 }
716 (void) initgroups(pwd->pw_name,
717 pwd->pw_gid);
718 if (setuid(pwd->pw_uid) < 0) {
719 syslog(LOG_ERR,
720 "%s/%s: can't set uid %d: %m", sep->se_service,
721 sep->se_proto, pwd->pw_uid);
722 goto reject;
723 }
724 } else if (sep->se_group) {
725 (void) setgid((gid_t)grp->gr_gid);
726 }
727 if (debug)
728 fprintf(stderr, "%d execl %s\n",
729 getpid(), sep->se_server);
730 #ifdef MULOG
731 if (sep->se_log)
732 dolog(sep, ctrl);
733 #endif
734 /* Set our control descriptor to not close-on-exec... */
735 if (fcntl(ctrl, F_SETFD, 0) < 0)
736 syslog(LOG_ERR, "fcntl (F_SETFD, 0): %m");
737 /* ...and dup it to stdin, stdout, and stderr. */
738 if (ctrl != 0) {
739 dup2(ctrl, 0);
740 close(ctrl);
741 ctrl = 0;
742 }
743 dup2(0, 1);
744 dup2(0, 2);
745 #ifdef RLIMIT_NOFILE
746 if (rlim_ofile.rlim_cur != rlim_ofile_cur &&
747 setrlimit(RLIMIT_NOFILE, &rlim_ofile) < 0)
748 syslog(LOG_ERR, "setrlimit: %m");
749 #endif
750 execv(sep->se_server, sep->se_argv);
751 syslog(LOG_ERR, "cannot execute %s: %m", sep->se_server);
752 reject:
753 if (sep->se_socktype != SOCK_STREAM)
754 recv(ctrl, buf, sizeof (buf), 0);
755 _exit(1);
756 }
757 }
758
759 static void
760 reapchild(void)
761 {
762 int status;
763 pid_t pid;
764 struct servtab *sep;
765
766 for (;;) {
767 pid = wait3(&status, WNOHANG, NULL);
768 if (pid <= 0)
769 break;
770 if (debug)
771 (void) fprintf(stderr, "%d reaped, status %#x\n",
772 pid, status);
773 for (sep = servtab; sep != NULL; sep = sep->se_next)
774 if (sep->se_wait == pid) {
775 struct kevent *ev;
776
777 if (WIFEXITED(status) && WEXITSTATUS(status))
778 syslog(LOG_WARNING,
779 "%s: exit status 0x%x",
780 sep->se_server, WEXITSTATUS(status));
781 else if (WIFSIGNALED(status))
782 syslog(LOG_WARNING,
783 "%s: exit signal 0x%x",
784 sep->se_server, WTERMSIG(status));
785 sep->se_wait = 1;
786 ev = allocchange();
787 EV_SET(ev, sep->se_fd, EVFILT_READ,
788 EV_ADD | EV_ENABLE, 0, 0, (intptr_t)sep);
789 if (debug)
790 fprintf(stderr, "restored %s, fd %d\n",
791 sep->se_service, sep->se_fd);
792 }
793 }
794 }
795
796 static void
797 config(void)
798 {
799 struct servtab *sep, *cp, **sepp;
800 size_t n;
801
802 if (!setconfig()) {
803 syslog(LOG_ERR, "%s: %m", CONFIG);
804 return;
805 }
806 for (sep = servtab; sep != NULL; sep = sep->se_next)
807 sep->se_checked = 0;
808 while ((cp = getconfigent())) {
809 for (sep = servtab; sep != NULL; sep = sep->se_next)
810 if (strcmp(sep->se_service, cp->se_service) == 0 &&
811 strcmp(sep->se_hostaddr, cp->se_hostaddr) == 0 &&
812 strcmp(sep->se_proto, cp->se_proto) == 0 &&
813 ISMUX(sep) == ISMUX(cp))
814 break;
815 if (sep != NULL) {
816 int i;
817
818 #define SWAP(type, a, b) {type c = a; a = b; b = c;}
819
820 /*
821 * sep->se_wait may be holding the pid of a daemon
822 * that we're waiting for. If so, don't overwrite
823 * it unless the config file explicitly says don't
824 * wait.
825 */
826 if (cp->se_bi == 0 &&
827 (sep->se_wait == 1 || cp->se_wait == 0))
828 sep->se_wait = cp->se_wait;
829 SWAP(char *, sep->se_user, cp->se_user);
830 SWAP(char *, sep->se_group, cp->se_group);
831 SWAP(char *, sep->se_server, cp->se_server);
832 for (i = 0; i < MAXARGV; i++)
833 SWAP(char *, sep->se_argv[i], cp->se_argv[i]);
834 #ifdef IPSEC
835 SWAP(char *, sep->se_policy, cp->se_policy);
836 #endif
837 SWAP(int, cp->se_type, sep->se_type);
838 SWAP(int, cp->se_max, sep->se_max);
839 #undef SWAP
840 if (isrpcservice(sep))
841 unregister_rpc(sep);
842 sep->se_rpcversl = cp->se_rpcversl;
843 sep->se_rpcversh = cp->se_rpcversh;
844 freeconfig(cp);
845 if (debug)
846 print_service("REDO", sep);
847 } else {
848 sep = enter(cp);
849 if (debug)
850 print_service("ADD ", sep);
851 }
852 sep->se_checked = 1;
853
854 switch (sep->se_family) {
855 case AF_LOCAL:
856 if (sep->se_fd != -1)
857 break;
858 n = strlen(sep->se_service);
859 if (n > sizeof(sep->se_ctrladdr_un.sun_path)) {
860 syslog(LOG_ERR, "%s: address too long",
861 sep->se_service);
862 sep->se_checked = 0;
863 continue;
864 }
865 (void)unlink(sep->se_service);
866 strncpy(sep->se_ctrladdr_un.sun_path,
867 sep->se_service, n);
868 sep->se_ctrladdr_un.sun_family = AF_LOCAL;
869 sep->se_ctrladdr_size = n +
870 sizeof(sep->se_ctrladdr_un) -
871 sizeof(sep->se_ctrladdr_un.sun_path);
872 if (!ISMUX(sep))
873 setup(sep);
874 break;
875 case AF_INET:
876 #ifdef INET6
877 case AF_INET6:
878 #endif
879 {
880 struct addrinfo hints, *res;
881 char *host, *port;
882 int error;
883 int s;
884
885 /* check if the family is supported */
886 s = socket(sep->se_family, SOCK_DGRAM, 0);
887 if (s < 0) {
888 syslog(LOG_WARNING,
889 "%s/%s: %s: the address family is not "
890 "supported by the kernel",
891 sep->se_service, sep->se_proto,
892 sep->se_hostaddr);
893 sep->se_checked = 0;
894 continue;
895 }
896 close(s);
897
898 memset(&hints, 0, sizeof(hints));
899 hints.ai_family = sep->se_family;
900 hints.ai_socktype = sep->se_socktype;
901 hints.ai_flags = AI_PASSIVE;
902 if (!strcmp(sep->se_hostaddr, "*"))
903 host = NULL;
904 else
905 host = sep->se_hostaddr;
906 if (isrpcservice(sep) || ISMUX(sep))
907 port = "0";
908 else
909 port = sep->se_service;
910 error = getaddrinfo(host, port, &hints, &res);
911 if (error) {
912 if (error == EAI_SERVICE) {
913 /* gai_strerror not friendly enough */
914 syslog(LOG_WARNING, "%s/%s: "
915 "unknown service",
916 sep->se_service, sep->se_proto);
917 } else {
918 syslog(LOG_ERR, "%s/%s: %s: %s",
919 sep->se_service, sep->se_proto,
920 sep->se_hostaddr,
921 gai_strerror(error));
922 }
923 sep->se_checked = 0;
924 continue;
925 }
926 if (res->ai_next) {
927 syslog(LOG_ERR,
928 "%s/%s: %s: resolved to multiple addr",
929 sep->se_service, sep->se_proto,
930 sep->se_hostaddr);
931 sep->se_checked = 0;
932 freeaddrinfo(res);
933 continue;
934 }
935 memcpy(&sep->se_ctrladdr, res->ai_addr,
936 res->ai_addrlen);
937 if (ISMUX(sep)) {
938 sep->se_fd = -1;
939 freeaddrinfo(res);
940 continue;
941 }
942 sep->se_ctrladdr_size = res->ai_addrlen;
943 freeaddrinfo(res);
944 #ifdef RPC
945 if (isrpcservice(sep)) {
946 struct rpcent *rp;
947
948 sep->se_rpcprog = atoi(sep->se_service);
949 if (sep->se_rpcprog == 0) {
950 rp = getrpcbyname(sep->se_service);
951 if (rp == 0) {
952 syslog(LOG_ERR,
953 "%s/%s: unknown service",
954 sep->se_service,
955 sep->se_proto);
956 sep->se_checked = 0;
957 continue;
958 }
959 sep->se_rpcprog = rp->r_number;
960 }
961 if (sep->se_fd == -1 && !ISMUX(sep))
962 setup(sep);
963 if (sep->se_fd != -1)
964 register_rpc(sep);
965 } else
966 #endif
967 {
968 if (sep->se_fd >= 0)
969 close_sep(sep);
970 if (sep->se_fd == -1 && !ISMUX(sep))
971 setup(sep);
972 }
973 }
974 }
975 }
976 endconfig();
977 /*
978 * Purge anything not looked at above.
979 */
980 sepp = &servtab;
981 while ((sep = *sepp)) {
982 if (sep->se_checked) {
983 sepp = &sep->se_next;
984 continue;
985 }
986 *sepp = sep->se_next;
987 if (sep->se_fd >= 0)
988 close_sep(sep);
989 if (isrpcservice(sep))
990 unregister_rpc(sep);
991 if (sep->se_family == AF_LOCAL)
992 (void)unlink(sep->se_service);
993 if (debug)
994 print_service("FREE", sep);
995 freeconfig(sep);
996 free(sep);
997 }
998 }
999
1000 static void
1001 retry(void)
1002 {
1003 struct servtab *sep;
1004
1005 timingout = 0;
1006 for (sep = servtab; sep != NULL; sep = sep->se_next) {
1007 if (sep->se_fd == -1 && !ISMUX(sep)) {
1008 switch (sep->se_family) {
1009 case AF_LOCAL:
1010 case AF_INET:
1011 #ifdef INET6
1012 case AF_INET6:
1013 #endif
1014 setup(sep);
1015 if (sep->se_fd != -1 && isrpcservice(sep))
1016 register_rpc(sep);
1017 break;
1018 }
1019 }
1020 }
1021 }
1022
1023 static void
1024 goaway(void)
1025 {
1026 struct servtab *sep;
1027
1028 for (sep = servtab; sep != NULL; sep = sep->se_next) {
1029 if (sep->se_fd == -1)
1030 continue;
1031
1032 switch (sep->se_family) {
1033 case AF_LOCAL:
1034 (void)unlink(sep->se_service);
1035 break;
1036 case AF_INET:
1037 #ifdef INET6
1038 case AF_INET6:
1039 #endif
1040 if (sep->se_wait == 1 && isrpcservice(sep))
1041 unregister_rpc(sep);
1042 break;
1043 }
1044 (void)close(sep->se_fd);
1045 }
1046 exit(0);
1047 }
1048
1049 static void
1050 setup(struct servtab *sep)
1051 {
1052 int on = 1;
1053 #ifdef INET6
1054 int off = 0;
1055 #endif
1056 struct kevent *ev;
1057
1058 if ((sep->se_fd = socket(sep->se_family, sep->se_socktype, 0)) < 0) {
1059 if (debug)
1060 fprintf(stderr, "socket failed on %s/%s: %s\n",
1061 sep->se_service, sep->se_proto, strerror(errno));
1062 syslog(LOG_ERR, "%s/%s: socket: %m",
1063 sep->se_service, sep->se_proto);
1064 return;
1065 }
1066 /* Set all listening sockets to close-on-exec. */
1067 if (fcntl(sep->se_fd, F_SETFD, FD_CLOEXEC) < 0) {
1068 syslog(LOG_ERR, "%s/%s: fcntl(F_SETFD, FD_CLOEXEC): %m",
1069 sep->se_service, sep->se_proto);
1070 close(sep->se_fd);
1071 return;
1072 }
1073
1074 #define turnon(fd, opt) \
1075 setsockopt(fd, SOL_SOCKET, opt, (char *)&on, sizeof (on))
1076 if (strcmp(sep->se_proto, "tcp") == 0 && (options & SO_DEBUG) &&
1077 turnon(sep->se_fd, SO_DEBUG) < 0)
1078 syslog(LOG_ERR, "setsockopt (SO_DEBUG): %m");
1079 if (turnon(sep->se_fd, SO_REUSEADDR) < 0)
1080 syslog(LOG_ERR, "setsockopt (SO_REUSEADDR): %m");
1081 #undef turnon
1082
1083 /* Set the socket buffer sizes, if specified. */
1084 if (sep->se_sndbuf != 0 && setsockopt(sep->se_fd, SOL_SOCKET,
1085 SO_SNDBUF, (char *)&sep->se_sndbuf, sizeof(sep->se_sndbuf)) < 0)
1086 syslog(LOG_ERR, "setsockopt (SO_SNDBUF %d): %m",
1087 sep->se_sndbuf);
1088 if (sep->se_rcvbuf != 0 && setsockopt(sep->se_fd, SOL_SOCKET,
1089 SO_RCVBUF, (char *)&sep->se_rcvbuf, sizeof(sep->se_rcvbuf)) < 0)
1090 syslog(LOG_ERR, "setsockopt (SO_RCVBUF %d): %m",
1091 sep->se_rcvbuf);
1092 #ifdef INET6
1093 if (sep->se_family == AF_INET6) {
1094 int *v;
1095 v = (sep->se_type == FAITH_TYPE) ? &on : &off;
1096 if (setsockopt(sep->se_fd, IPPROTO_IPV6, IPV6_FAITH,
1097 (char *)v, sizeof(*v)) < 0)
1098 syslog(LOG_ERR, "setsockopt (IPV6_FAITH): %m");
1099 }
1100 #endif
1101 #ifdef IPSEC
1102 if (ipsecsetup(sep->se_family, sep->se_fd, sep->se_policy) < 0 &&
1103 sep->se_policy) {
1104 syslog(LOG_ERR, "%s/%s: ipsec setup failed",
1105 sep->se_service, sep->se_proto);
1106 (void)close(sep->se_fd);
1107 sep->se_fd = -1;
1108 return;
1109 }
1110 #endif
1111
1112 if (bind(sep->se_fd, &sep->se_ctrladdr, sep->se_ctrladdr_size) < 0) {
1113 if (debug)
1114 fprintf(stderr, "bind failed on %s/%s: %s\n",
1115 sep->se_service, sep->se_proto, strerror(errno));
1116 syslog(LOG_ERR, "%s/%s: bind: %m",
1117 sep->se_service, sep->se_proto);
1118 (void) close(sep->se_fd);
1119 sep->se_fd = -1;
1120 if (!timingout) {
1121 timingout = 1;
1122 alarm(RETRYTIME);
1123 }
1124 return;
1125 }
1126 if (sep->se_socktype == SOCK_STREAM)
1127 listen(sep->se_fd, 10);
1128
1129 ev = allocchange();
1130 EV_SET(ev, sep->se_fd, EVFILT_READ, EV_ADD | EV_ENABLE, 0, 0,
1131 (intptr_t)sep);
1132 if (sep->se_fd > maxsock) {
1133 maxsock = sep->se_fd;
1134 if (maxsock > rlim_ofile_cur - FD_MARGIN)
1135 bump_nofile();
1136 }
1137 if (debug)
1138 fprintf(stderr, "registered %s on %d\n",
1139 sep->se_server, sep->se_fd);
1140 }
1141
1142 /*
1143 * Finish with a service and its socket.
1144 */
1145 static void
1146 close_sep(struct servtab *sep)
1147 {
1148 if (sep->se_fd >= 0) {
1149 (void) close(sep->se_fd);
1150 sep->se_fd = -1;
1151 }
1152 sep->se_count = 0;
1153 }
1154
1155 static void
1156 register_rpc(struct servtab *sep)
1157 {
1158 #ifdef RPC
1159 struct netbuf nbuf;
1160 struct sockaddr_storage ss;
1161 struct netconfig *nconf;
1162 socklen_t socklen;
1163 int n;
1164
1165 if ((nconf = getnetconfigent(sep->se_proto+4)) == NULL) {
1166 syslog(LOG_ERR, "%s: getnetconfigent failed",
1167 sep->se_proto);
1168 return;
1169 }
1170 socklen = sizeof ss;
1171 if (getsockname(sep->se_fd, (struct sockaddr *)&ss, &socklen) < 0) {
1172 syslog(LOG_ERR, "%s/%s: getsockname: %m",
1173 sep->se_service, sep->se_proto);
1174 return;
1175 }
1176
1177 nbuf.buf = &ss;
1178 nbuf.len = ss.ss_len;
1179 nbuf.maxlen = sizeof (struct sockaddr_storage);
1180 for (n = sep->se_rpcversl; n <= sep->se_rpcversh; n++) {
1181 if (debug)
1182 fprintf(stderr, "rpcb_set: %u %d %s %s\n",
1183 sep->se_rpcprog, n, nconf->nc_netid,
1184 taddr2uaddr(nconf, &nbuf));
1185 (void)rpcb_unset(sep->se_rpcprog, n, nconf);
1186 if (!rpcb_set(sep->se_rpcprog, n, nconf, &nbuf))
1187 syslog(LOG_ERR, "rpcb_set: %u %d %s %s%s",
1188 sep->se_rpcprog, n, nconf->nc_netid,
1189 taddr2uaddr(nconf, &nbuf), clnt_spcreateerror(""));
1190 }
1191 #endif /* RPC */
1192 }
1193
1194 static void
1195 unregister_rpc(struct servtab *sep)
1196 {
1197 #ifdef RPC
1198 int n;
1199 struct netconfig *nconf;
1200
1201 if ((nconf = getnetconfigent(sep->se_proto+4)) == NULL) {
1202 syslog(LOG_ERR, "%s: getnetconfigent failed",
1203 sep->se_proto);
1204 return;
1205 }
1206
1207 for (n = sep->se_rpcversl; n <= sep->se_rpcversh; n++) {
1208 if (debug)
1209 fprintf(stderr, "rpcb_unset(%u, %d, %s)\n",
1210 sep->se_rpcprog, n, nconf->nc_netid);
1211 if (!rpcb_unset(sep->se_rpcprog, n, nconf))
1212 syslog(LOG_ERR, "rpcb_unset(%u, %d, %s) failed\n",
1213 sep->se_rpcprog, n, nconf->nc_netid);
1214 }
1215 #endif /* RPC */
1216 }
1217
1218
1219 static struct servtab *
1220 enter(struct servtab *cp)
1221 {
1222 struct servtab *sep;
1223
1224 sep = (struct servtab *)malloc(sizeof (*sep));
1225 if (sep == NULL) {
1226 syslog(LOG_ERR, "Out of memory.");
1227 exit(1);
1228 }
1229 *sep = *cp;
1230 sep->se_fd = -1;
1231 sep->se_rpcprog = -1;
1232 sep->se_next = servtab;
1233 servtab = sep;
1234 return (sep);
1235 }
1236
1237 FILE *fconfig = NULL;
1238 struct servtab serv;
1239 char line[LINE_MAX];
1240 char *defhost;
1241 #ifdef IPSEC
1242 static char *policy = NULL;
1243 #endif
1244
1245 static int
1246 setconfig(void)
1247 {
1248 if (defhost)
1249 free(defhost);
1250 defhost = newstr("*");
1251 #ifdef IPSEC
1252 if (policy)
1253 free(policy);
1254 policy = NULL;
1255 #endif
1256 if (fconfig != NULL) {
1257 fseek(fconfig, 0L, SEEK_SET);
1258 return (1);
1259 }
1260 fconfig = fopen(CONFIG, "r");
1261 return (fconfig != NULL);
1262 }
1263
1264 static void
1265 endconfig(void)
1266 {
1267 if (fconfig != NULL) {
1268 (void) fclose(fconfig);
1269 fconfig = NULL;
1270 }
1271 if (defhost != NULL) {
1272 free(defhost);
1273 defhost = NULL;
1274 }
1275 }
1276
1277 static struct servtab *
1278 getconfigent(void)
1279 {
1280 struct servtab *sep = &serv;
1281 int argc, val;
1282 char *cp, *cp0, *arg, *buf0, *buf1, *sz0, *sz1;
1283 static char TCPMUX_TOKEN[] = "tcpmux/";
1284 #define MUX_LEN (sizeof(TCPMUX_TOKEN)-1)
1285 char *hostdelim;
1286
1287 more:
1288 while ((cp = nextline(fconfig))) {
1289 #ifdef IPSEC
1290 /* lines starting with #@ is not a comment, but the policy */
1291 if (cp[0] == '#' && cp[1] == '@') {
1292 char *p;
1293 for (p = cp + 2; p && *p && isspace((unsigned char)*p); p++)
1294 ;
1295 if (*p == '\0') {
1296 if (policy)
1297 free(policy);
1298 policy = NULL;
1299 } else {
1300 if (ipsecsetup_test(p) < 0) {
1301 syslog(LOG_ERR,
1302 "%s: invalid ipsec policy \"%s\"",
1303 CONFIG, p);
1304 exit(1);
1305 } else {
1306 if (policy)
1307 free(policy);
1308 policy = newstr(p);
1309 }
1310 }
1311 }
1312 #endif
1313 if (*cp == '#' || *cp == '\0')
1314 continue;
1315 #ifdef MULOG
1316 /* Avoid use of `skip' if there is a danger of it looking
1317 * at continuation lines.
1318 */
1319 do {
1320 cp++;
1321 } while (*cp == ' ' || *cp == '\t');
1322 if (*cp == '\0')
1323 continue;
1324 if ((arg = skip(&cp)) == NULL)
1325 continue;
1326 if (strcmp(arg, "DOMAIN"))
1327 continue;
1328 if (curdom)
1329 free(curdom);
1330 curdom = NULL;
1331 while (*cp == ' ' || *cp == '\t')
1332 cp++;
1333 if (*cp == '\0')
1334 continue;
1335 arg = cp;
1336 while (*cp && *cp != ' ' && *cp != '\t')
1337 cp++;
1338 if (*cp != '\0')
1339 *cp++ = '\0';
1340 curdom = newstr(arg);
1341 #endif
1342 break;
1343 }
1344 if (cp == NULL)
1345 return (NULL);
1346 /*
1347 * clear the static buffer, since some fields (se_ctrladdr,
1348 * for example) don't get initialized here.
1349 */
1350 memset((caddr_t)sep, 0, sizeof *sep);
1351 arg = skip(&cp);
1352 if (cp == NULL) {
1353 /* got an empty line containing just blanks/tabs. */
1354 goto more;
1355 }
1356 /* Check for a host name. */
1357 hostdelim = strrchr(arg, ':');
1358 if (hostdelim) {
1359 *hostdelim = '\0';
1360 if (arg[0] == '[' && hostdelim > arg && hostdelim[-1] == ']') {
1361 hostdelim[-1] = '\0';
1362 sep->se_hostaddr = newstr(arg + 1);
1363 } else
1364 sep->se_hostaddr = newstr(arg);
1365 arg = hostdelim + 1;
1366 /*
1367 * If the line is of the form `host:', then just change the
1368 * default host for the following lines.
1369 */
1370 if (*arg == '\0') {
1371 arg = skip(&cp);
1372 if (cp == NULL) {
1373 free(defhost);
1374 defhost = sep->se_hostaddr;
1375 goto more;
1376 }
1377 }
1378 } else
1379 sep->se_hostaddr = newstr(defhost);
1380 if (strncmp(arg, TCPMUX_TOKEN, MUX_LEN) == 0) {
1381 char *c = arg + MUX_LEN;
1382 if (*c == '+') {
1383 sep->se_type = MUXPLUS_TYPE;
1384 c++;
1385 } else
1386 sep->se_type = MUX_TYPE;
1387 sep->se_service = newstr(c);
1388 } else {
1389 sep->se_service = newstr(arg);
1390 sep->se_type = NORM_TYPE;
1391 }
1392
1393 arg = sskip(&cp);
1394 if (strcmp(arg, "stream") == 0)
1395 sep->se_socktype = SOCK_STREAM;
1396 else if (strcmp(arg, "dgram") == 0)
1397 sep->se_socktype = SOCK_DGRAM;
1398 else if (strcmp(arg, "rdm") == 0)
1399 sep->se_socktype = SOCK_RDM;
1400 else if (strcmp(arg, "seqpacket") == 0)
1401 sep->se_socktype = SOCK_SEQPACKET;
1402 else if (strcmp(arg, "raw") == 0)
1403 sep->se_socktype = SOCK_RAW;
1404 else
1405 sep->se_socktype = -1;
1406
1407 arg = sskip(&cp);
1408 if (sep->se_type == NORM_TYPE &&
1409 strncmp(arg, "faith/", strlen("faith/")) == 0) {
1410 arg += strlen("faith/");
1411 sep->se_type = FAITH_TYPE;
1412 }
1413 sep->se_proto = newstr(arg);
1414
1415 #define MALFORMED(arg) \
1416 do { \
1417 syslog(LOG_ERR, "%s: malformed buffer size option `%s'", \
1418 sep->se_service, (arg)); \
1419 goto more; \
1420 } while (0)
1421
1422 #define GETVAL(arg) \
1423 do { \
1424 if (!isdigit((unsigned char)*(arg))) \
1425 MALFORMED(arg); \
1426 val = strtol((arg), &cp0, 10); \
1427 if (cp0 != NULL) { \
1428 if (cp0[1] != '\0') \
1429 MALFORMED((arg)); \
1430 if (cp0[0] == 'k') \
1431 val *= 1024; \
1432 if (cp0[0] == 'm') \
1433 val *= 1024 * 1024; \
1434 } \
1435 if (val < 1) { \
1436 syslog(LOG_ERR, "%s: invalid buffer size `%s'", \
1437 sep->se_service, (arg)); \
1438 goto more; \
1439 } \
1440 } while (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 (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 = 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 *cp, *ccp;
1535 cp = strchr(sep->se_service, '/');
1536 if (cp == 0) {
1537 syslog(LOG_ERR, "%s: no rpc version",
1538 sep->se_service);
1539 goto more;
1540 }
1541 *cp++ = '\0';
1542 sep->se_rpcversl = sep->se_rpcversh =
1543 strtol(cp, &ccp, 0);
1544 if (ccp == cp) {
1545 badafterall:
1546 syslog(LOG_ERR, "%s/%s: bad rpc version",
1547 sep->se_service, cp);
1548 goto more;
1549 }
1550 if (*ccp == '-') {
1551 cp = ccp + 1;
1552 sep->se_rpcversh = strtol(cp, &ccp, 0);
1553 if (ccp == cp)
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 *cp;
1566 if ((cp = strchr(arg, ':')) == NULL)
1567 cp = strchr(arg, '.');
1568 if (cp != NULL) {
1569 *cp++ = '\0';
1570 sep->se_max = atoi(cp);
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 MULOG
1621 char *colon;
1622
1623 if (argc == 0 && (colon = strrchr(arg, ':'))) {
1624 while (arg < colon) {
1625 int x;
1626 char *ccp;
1627
1628 switch (*arg++) {
1629 case 'l':
1630 x = 1;
1631 if (isdigit(*arg)) {
1632 x = strtol(arg, &ccp, 0);
1633 if (ccp == arg)
1634 break;
1635 arg = ccp;
1636 }
1637 sep->se_log &= ~MULOG_RFC931;
1638 sep->se_log |= x;
1639 break;
1640 case 'a':
1641 sep->se_log |= MULOG_RFC931;
1642 break;
1643 default:
1644 break;
1645 }
1646 }
1647 arg = colon + 1;
1648 }
1649 #endif
1650 if (argc < MAXARGV)
1651 sep->se_argv[argc++] = newstr(arg);
1652 }
1653 while (argc <= MAXARGV)
1654 sep->se_argv[argc++] = NULL;
1655 #ifdef IPSEC
1656 sep->se_policy = policy ? newstr(policy) : NULL;
1657 #endif
1658 return (sep);
1659 }
1660
1661 static void
1662 freeconfig(struct servtab *cp)
1663 {
1664 int i;
1665
1666 if (cp->se_hostaddr)
1667 free(cp->se_hostaddr);
1668 if (cp->se_service)
1669 free(cp->se_service);
1670 if (cp->se_proto)
1671 free(cp->se_proto);
1672 if (cp->se_user)
1673 free(cp->se_user);
1674 /* Note: se_group is part of the newstr'ed se_user */
1675 if (cp->se_server)
1676 free(cp->se_server);
1677 for (i = 0; i < MAXARGV; i++)
1678 if (cp->se_argv[i])
1679 free(cp->se_argv[i]);
1680 #ifdef IPSEC
1681 if (cp->se_policy)
1682 free(cp->se_policy);
1683 #endif
1684 }
1685
1686
1687 /*
1688 * Safe skip - if skip returns null, log a syntax error in the
1689 * configuration file and exit.
1690 */
1691 static char *
1692 sskip(char **cpp)
1693 {
1694 char *cp;
1695
1696 cp = skip(cpp);
1697 if (cp == NULL) {
1698 syslog(LOG_ERR, "%s: syntax error", CONFIG);
1699 exit(1);
1700 }
1701 return (cp);
1702 }
1703
1704 static char *
1705 skip(char **cpp)
1706 {
1707 char *cp = *cpp;
1708 char *start;
1709 char quote;
1710
1711 if (*cpp == NULL)
1712 return (NULL);
1713
1714 again:
1715 while (*cp == ' ' || *cp == '\t')
1716 cp++;
1717 if (*cp == '\0') {
1718 int c;
1719
1720 c = getc(fconfig);
1721 (void) ungetc(c, fconfig);
1722 if (c == ' ' || c == '\t')
1723 if ((cp = nextline(fconfig)))
1724 goto again;
1725 *cpp = NULL;
1726 return (NULL);
1727 }
1728 start = cp;
1729 quote = '\0';
1730 while (*cp && (quote || (*cp != ' ' && *cp != '\t'))) {
1731 if (*cp == '\'' || *cp == '"') {
1732 if (quote && *cp != quote)
1733 cp++;
1734 else {
1735 if (quote)
1736 quote = '\0';
1737 else
1738 quote = *cp;
1739 memmove(cp, cp+1, strlen(cp));
1740 }
1741 } else
1742 cp++;
1743 }
1744 if (*cp != '\0')
1745 *cp++ = '\0';
1746 *cpp = cp;
1747 return (start);
1748 }
1749
1750 static char *
1751 nextline(FILE *fd)
1752 {
1753 char *cp;
1754
1755 if (fgets(line, sizeof (line), fd) == NULL)
1756 return (NULL);
1757 cp = strchr(line, '\n');
1758 if (cp)
1759 *cp = '\0';
1760 return (line);
1761 }
1762
1763 static char *
1764 newstr(char *cp)
1765 {
1766 if ((cp = strdup((cp != NULL) ? cp : "")) != NULL)
1767 return (cp);
1768 syslog(LOG_ERR, "strdup: %m");
1769 exit(1);
1770 }
1771
1772 static void
1773 inetd_setproctitle(char *a, int s)
1774 {
1775 socklen_t size;
1776 struct sockaddr_storage ss;
1777 char hbuf[NI_MAXHOST], *hp;
1778
1779 size = sizeof(ss);
1780 if (getpeername(s, (struct sockaddr *)&ss, &size) == 0) {
1781 if (getnameinfo((struct sockaddr *)&ss, size, hp = hbuf,
1782 sizeof(hbuf), NULL, 0, niflags) != 0)
1783 hp = "?";
1784 setproctitle("-%s [%s]", a, hp);
1785 } else
1786 setproctitle("-%s", a);
1787 }
1788
1789 static void
1790 bump_nofile(void)
1791 {
1792 #ifdef RLIMIT_NOFILE
1793
1794 #define FD_CHUNK 32
1795
1796 struct rlimit rl;
1797
1798 if (getrlimit(RLIMIT_NOFILE, &rl) < 0) {
1799 syslog(LOG_ERR, "getrlimit: %m");
1800 return;
1801 }
1802 rl.rlim_cur = MIN(rl.rlim_max, rl.rlim_cur + FD_CHUNK);
1803 if (rl.rlim_cur <= rlim_ofile_cur) {
1804 syslog(LOG_ERR,
1805 "bump_nofile: cannot extend file limit, max = %d",
1806 (int)rl.rlim_cur);
1807 return;
1808 }
1809
1810 if (setrlimit(RLIMIT_NOFILE, &rl) < 0) {
1811 syslog(LOG_ERR, "setrlimit: %m");
1812 return;
1813 }
1814
1815 rlim_ofile_cur = rl.rlim_cur;
1816 return;
1817
1818 #else
1819 syslog(LOG_ERR, "bump_nofile: cannot extend file limit");
1820 return;
1821 #endif
1822 }
1823
1824 /*
1825 * Internet services provided internally by inetd:
1826 */
1827 #define BUFSIZE 4096
1828
1829 /* ARGSUSED */
1830 static void
1831 echo_stream(int s, struct servtab *sep) /* Echo service -- echo data back */
1832 {
1833 char buffer[BUFSIZE];
1834 int i;
1835
1836 inetd_setproctitle(sep->se_service, s);
1837 while ((i = read(s, buffer, sizeof(buffer))) > 0 &&
1838 write(s, buffer, i) > 0)
1839 ;
1840 }
1841
1842 /* ARGSUSED */
1843 static void
1844 echo_dg(int s, struct servtab *sep) /* Echo service -- echo data back */
1845 {
1846 char buffer[BUFSIZE];
1847 int i;
1848 socklen_t size;
1849 struct sockaddr_storage ss;
1850 struct sockaddr *sa;
1851
1852 sa = (struct sockaddr *)&ss;
1853 size = sizeof(ss);
1854 if ((i = recvfrom(s, buffer, sizeof(buffer), 0, sa, &size)) < 0)
1855 return;
1856 if (port_good_dg(sa))
1857 (void) sendto(s, buffer, i, 0, sa, size);
1858 }
1859
1860 /* ARGSUSED */
1861 static void
1862 discard_stream(int s, struct servtab *sep) /* Discard service -- ignore data */
1863 {
1864 char buffer[BUFSIZE];
1865
1866 inetd_setproctitle(sep->se_service, s);
1867 while ((errno = 0, read(s, buffer, sizeof(buffer)) > 0) ||
1868 errno == EINTR)
1869 ;
1870 }
1871
1872 /* ARGSUSED */
1873 static void
1874 discard_dg(int s, struct servtab *sep) /* Discard service -- ignore data */
1875
1876 {
1877 char buffer[BUFSIZE];
1878
1879 (void) read(s, buffer, sizeof(buffer));
1880 }
1881
1882 #define LINESIZ 72
1883 char ring[128];
1884 char *endring;
1885
1886 static void
1887 initring(void)
1888 {
1889 int i;
1890
1891 endring = ring;
1892
1893 for (i = 0; i <= 128; ++i)
1894 if (isprint(i))
1895 *endring++ = i;
1896 }
1897
1898 /* ARGSUSED */
1899 static void
1900 chargen_stream(int s,struct servtab *sep) /* Character generator */
1901 {
1902 int len;
1903 char *rs, text[LINESIZ+2];
1904
1905 inetd_setproctitle(sep->se_service, s);
1906
1907 if (!endring) {
1908 initring();
1909 rs = ring;
1910 }
1911
1912 text[LINESIZ] = '\r';
1913 text[LINESIZ + 1] = '\n';
1914 for (rs = ring;;) {
1915 if ((len = endring - rs) >= LINESIZ)
1916 memmove(text, rs, LINESIZ);
1917 else {
1918 memmove(text, rs, len);
1919 memmove(text + len, ring, LINESIZ - len);
1920 }
1921 if (++rs == endring)
1922 rs = ring;
1923 if (write(s, text, sizeof(text)) != sizeof(text))
1924 break;
1925 }
1926 }
1927
1928 /* ARGSUSED */
1929 static void
1930 chargen_dg(int s, struct servtab *sep) /* Character generator */
1931 {
1932 struct sockaddr_storage ss;
1933 struct sockaddr *sa;
1934 static char *rs;
1935 int len;
1936 socklen_t size;
1937 char text[LINESIZ+2];
1938
1939 if (endring == 0) {
1940 initring();
1941 rs = ring;
1942 }
1943
1944 sa = (struct sockaddr *)&ss;
1945 size = sizeof(ss);
1946 if (recvfrom(s, text, sizeof(text), 0, sa, &size) < 0)
1947 return;
1948
1949 if (!port_good_dg(sa))
1950 return;
1951
1952 if ((len = endring - rs) >= LINESIZ)
1953 memmove(text, rs, LINESIZ);
1954 else {
1955 memmove(text, rs, len);
1956 memmove(text + len, ring, LINESIZ - len);
1957 }
1958 if (++rs == endring)
1959 rs = ring;
1960 text[LINESIZ] = '\r';
1961 text[LINESIZ + 1] = '\n';
1962 (void) sendto(s, text, sizeof(text), 0, sa, size);
1963 }
1964
1965 /*
1966 * Return a machine readable date and time, in the form of the
1967 * number of seconds since midnight, Jan 1, 1900. Since gettimeofday
1968 * returns the number of seconds since midnight, Jan 1, 1970,
1969 * we must add 2208988800 seconds to this figure to make up for
1970 * some seventy years Bell Labs was asleep.
1971 */
1972
1973 static uint32_t
1974 machtime(void)
1975 {
1976 struct timeval tv;
1977
1978 if (gettimeofday(&tv, NULL) < 0) {
1979 if (debug)
1980 fprintf(stderr, "Unable to get time of day\n");
1981 return (0);
1982 }
1983 #define OFFSET ((uint32_t)25567 * 24*60*60)
1984 return (htonl((uint32_t)(tv.tv_sec + OFFSET)));
1985 #undef OFFSET
1986 }
1987
1988 /* ARGSUSED */
1989 static void
1990 machtime_stream(int s, struct servtab *sep)
1991 {
1992 uint32_t result;
1993
1994 result = machtime();
1995 (void) write(s, (char *) &result, sizeof(result));
1996 }
1997
1998 /* ARGSUSED */
1999 void
2000 machtime_dg(int s, struct servtab *sep)
2001 {
2002 uint32_t result;
2003 struct sockaddr_storage ss;
2004 struct sockaddr *sa;
2005 socklen_t size;
2006
2007 sa = (struct sockaddr *)&ss;
2008 size = sizeof(ss);
2009 if (recvfrom(s, (char *)&result, sizeof(result), 0, sa, &size) < 0)
2010 return;
2011 if (!port_good_dg(sa))
2012 return;
2013 result = machtime();
2014 (void) sendto(s, (char *) &result, sizeof(result), 0, sa, size);
2015 }
2016
2017 /* ARGSUSED */
2018 static void
2019 daytime_stream(int s,struct servtab *sep)
2020 /* Return human-readable time of day */
2021 {
2022 char buffer[256];
2023 time_t clock;
2024 int len;
2025
2026 clock = time((time_t *) 0);
2027
2028 len = snprintf(buffer, sizeof buffer, "%.24s\r\n", ctime(&clock));
2029 (void) write(s, buffer, len);
2030 }
2031
2032 /* ARGSUSED */
2033 void
2034 daytime_dg(int s, struct servtab *sep)
2035 /* Return human-readable time of day */
2036 {
2037 char buffer[256];
2038 time_t clock;
2039 struct sockaddr_storage ss;
2040 struct sockaddr *sa;
2041 socklen_t size;
2042 int len;
2043
2044 clock = time((time_t *) 0);
2045
2046 sa = (struct sockaddr *)&ss;
2047 size = sizeof(ss);
2048 if (recvfrom(s, buffer, sizeof(buffer), 0, sa, &size) < 0)
2049 return;
2050 if (!port_good_dg(sa))
2051 return;
2052 len = snprintf(buffer, sizeof buffer, "%.24s\r\n", ctime(&clock));
2053 (void) sendto(s, buffer, len, 0, sa, size);
2054 }
2055
2056 /*
2057 * print_service:
2058 * Dump relevant information to stderr
2059 */
2060 static void
2061 print_service(char *action, struct servtab *sep)
2062 {
2063
2064 if (isrpcservice(sep))
2065 fprintf(stderr,
2066 "%s: %s rpcprog=%d, rpcvers = %d/%d, proto=%s, wait.max=%d.%d, user:group=%s:%s builtin=%lx server=%s"
2067 #ifdef IPSEC
2068 " policy=\"%s\""
2069 #endif
2070 "\n",
2071 action, sep->se_service,
2072 sep->se_rpcprog, sep->se_rpcversh, sep->se_rpcversl, sep->se_proto,
2073 sep->se_wait, sep->se_max, sep->se_user, sep->se_group,
2074 (long)sep->se_bi, sep->se_server
2075 #ifdef IPSEC
2076 , (sep->se_policy ? sep->se_policy : "")
2077 #endif
2078 );
2079 else
2080 fprintf(stderr,
2081 "%s: %s proto=%s%s, wait.max=%d.%d, user:group=%s:%s builtin=%lx server=%s"
2082 #ifdef IPSEC
2083 " policy=%s"
2084 #endif
2085 "\n",
2086 action, sep->se_service,
2087 sep->se_type == FAITH_TYPE ? "faith/" : "",
2088 sep->se_proto,
2089 sep->se_wait, sep->se_max, sep->se_user, sep->se_group,
2090 (long)sep->se_bi, sep->se_server
2091 #ifdef IPSEC
2092 , (sep->se_policy ? sep->se_policy : "")
2093 #endif
2094 );
2095 }
2096
2097 static void
2098 usage(void)
2099 {
2100 #ifdef LIBWRAP
2101 (void)fprintf(stderr, "usage: %s [-dl] [conf]\n", getprogname());
2102 #else
2103 (void)fprintf(stderr, "usage: %s [-d] [conf]\n", getprogname());
2104 #endif
2105 exit(1);
2106 }
2107
2108
2109 /*
2110 * Based on TCPMUX.C by Mark K. Lottor November 1988
2111 * sri-nic::ps:<mkl>tcpmux.c
2112 */
2113
2114 static int /* # of characters upto \r,\n or \0 */
2115 getline(int fd, char *buf, int len)
2116 {
2117 int count = 0, n;
2118
2119 do {
2120 n = read(fd, buf, len-count);
2121 if (n == 0)
2122 return (count);
2123 if (n < 0)
2124 return (-1);
2125 while (--n >= 0) {
2126 if (*buf == '\r' || *buf == '\n' || *buf == '\0')
2127 return (count);
2128 count++;
2129 buf++;
2130 }
2131 } while (count < len);
2132 return (count);
2133 }
2134
2135 #define MAX_SERV_LEN (256+2) /* 2 bytes for \r\n */
2136
2137 #define strwrite(fd, buf) (void) write(fd, buf, sizeof(buf)-1)
2138
2139 static void
2140 tcpmux(int ctrl, struct servtab *sep)
2141 {
2142 char service[MAX_SERV_LEN+1];
2143 int len;
2144
2145 /* Get requested service name */
2146 if ((len = getline(ctrl, service, MAX_SERV_LEN)) < 0) {
2147 strwrite(ctrl, "-Error reading service name\r\n");
2148 goto reject;
2149 }
2150 service[len] = '\0';
2151
2152 if (debug)
2153 fprintf(stderr, "tcpmux: someone wants %s\n", service);
2154
2155 /*
2156 * Help is a required command, and lists available services,
2157 * one per line.
2158 */
2159 if (!strcasecmp(service, "help")) {
2160 strwrite(ctrl, "+Available services:\r\n");
2161 strwrite(ctrl, "help\r\n");
2162 for (sep = servtab; sep != NULL; sep = sep->se_next) {
2163 if (!ISMUX(sep))
2164 continue;
2165 (void)write(ctrl, sep->se_service,
2166 strlen(sep->se_service));
2167 strwrite(ctrl, "\r\n");
2168 }
2169 goto reject;
2170 }
2171
2172 /* Try matching a service in inetd.conf with the request */
2173 for (sep = servtab; sep != NULL; sep = sep->se_next) {
2174 if (!ISMUX(sep))
2175 continue;
2176 if (!strcasecmp(service, sep->se_service)) {
2177 if (ISMUXPLUS(sep))
2178 strwrite(ctrl, "+Go\r\n");
2179 run_service(ctrl, sep, 1 /* forked */);
2180 return;
2181 }
2182 }
2183 strwrite(ctrl, "-Service not available\r\n");
2184 reject:
2185 _exit(1);
2186 }
2187
2188 #ifdef MULOG
2189 void
2190 dolog(struct servtab *sep, int ctrl)
2191 {
2192 struct sockaddr_storage ss;
2193 struct sockaddr *sa = (struct sockaddr *)&ss;
2194 socklen_t len = sizeof(ss);
2195 char *host, *dp, buf[BUFSIZ];
2196 int connected = 1;
2197
2198 switch (sep->se_family) {
2199 case AF_INET:
2200 #ifdef INET6
2201 case AF_INET6:
2202 #endif
2203 break;
2204 default:
2205 return;
2206 }
2207
2208 if (getpeername(ctrl, sa, &len) < 0) {
2209 if (errno != ENOTCONN) {
2210 syslog(LOG_ERR, "getpeername: %m");
2211 return;
2212 }
2213 if (recvfrom(ctrl, buf, sizeof(buf), MSG_PEEK, sa, &len) < 0) {
2214 syslog(LOG_ERR, "recvfrom: %m");
2215 return;
2216 }
2217 connected = 0;
2218 }
2219 switch (sa->sa_family) {
2220 case AF_INET:
2221 #ifdef INET6
2222 case AF_INET6:
2223 #endif
2224 break;
2225 default:
2226 syslog(LOG_ERR, "unexpected address family %u", sa->sa_family);
2227 return;
2228 }
2229
2230 if (getnameinfo(sa, len, buf, sizeof(buf), NULL, 0, 0) != 0)
2231 strlcpy(buf, "?", sizeof(buf));
2232 host = buf;
2233
2234 switch (sep->se_log & ~MULOG_RFC931) {
2235 case 0:
2236 return;
2237 case 1:
2238 if (curdom == NULL || *curdom == '\0')
2239 break;
2240 dp = host + strlen(host) - strlen(curdom);
2241 if (dp < host)
2242 break;
2243 if (debug)
2244 fprintf(stderr, "check \"%s\" against curdom \"%s\"\n",
2245 host, curdom);
2246 if (strcasecmp(dp, curdom) == 0)
2247 return;
2248 break;
2249 case 2:
2250 default:
2251 break;
2252 }
2253
2254 openlog("", LOG_NOWAIT, MULOG);
2255
2256 if (connected && (sep->se_log & MULOG_RFC931))
2257 syslog(LOG_INFO, "%s@%s wants %s",
2258 rfc931_name(sa, ctrl), host, sep->se_service);
2259 else
2260 syslog(LOG_INFO, "%s wants %s",
2261 host, sep->se_service);
2262 }
2263
2264 /*
2265 * From tcp_log by
2266 * Wietse Venema, Eindhoven University of Technology, The Netherlands.
2267 */
2268 #if 0
2269 static char sccsid[] = "@(#) rfc931.c 1.3 92/08/31 22:54:46";
2270 #endif
2271
2272 #include <setjmp.h>
2273
2274 #define RFC931_PORT 113 /* Semi-well-known port */
2275 #define TIMEOUT 4
2276 #define TIMEOUT2 10
2277
2278 static jmp_buf timebuf;
2279
2280 /* timeout - handle timeouts */
2281
2282 static void
2283 timeout(int sig)
2284 {
2285 longjmp(timebuf, sig);
2286 }
2287
2288 /* rfc931_name - return remote user name */
2289
2290 char *
2291 rfc931_name(struct sockaddr *there, /* remote link information */
2292 int ctrl)
2293 {
2294 struct sockaddr_storage here; /* local link information */
2295 struct sockaddr_storage sin; /* for talking to RFC931 daemon */
2296 socklen_t length;
2297 int s;
2298 unsigned remote;
2299 unsigned local;
2300 static char user[256]; /* XXX */
2301 char buf[256];
2302 char *cp;
2303 char *result = "USER_UNKNOWN";
2304 int len;
2305 u_int16_t myport, hisport;
2306
2307 /* Find out local port number of our stdin. */
2308
2309 length = sizeof(here);
2310 if (getsockname(ctrl, (struct sockaddr *) &here, &length) == -1) {
2311 syslog(LOG_ERR, "getsockname: %m");
2312 return (result);
2313 }
2314 switch (here.ss_family) {
2315 case AF_INET:
2316 myport = ((struct sockaddr_in *)&here)->sin_port;
2317 break;
2318 #ifdef INET6
2319 case AF_INET6:
2320 myport = ((struct sockaddr_in6 *)&here)->sin6_port;
2321 break;
2322 #endif
2323 }
2324 switch (there->sa_family) {
2325 case AF_INET:
2326 hisport = ((struct sockaddr_in *)&there)->sin_port;
2327 break;
2328 #ifdef INET6
2329 case AF_INET6:
2330 hisport = ((struct sockaddr_in6 *)&there)->sin6_port;
2331 break;
2332 #endif
2333 }
2334 /* Set up timer so we won't get stuck. */
2335
2336 if ((s = socket(here.ss_family, SOCK_STREAM, 0)) == -1) {
2337 syslog(LOG_ERR, "socket: %m");
2338 return (result);
2339 }
2340
2341 sin = here;
2342 switch (sin.ss_family) {
2343 case AF_INET:
2344 ((struct sockaddr_in *)&sin)->sin_port = htons(0);
2345 break;
2346 #ifdef INET6
2347 case AF_INET6:
2348 ((struct sockaddr_in6 *)&sin)->sin6_port = htons(0);
2349 break;
2350 #endif
2351 }
2352 if (bind(s, (struct sockaddr *) &sin, sin.ss_len) == -1) {
2353 syslog(LOG_ERR, "bind: %m");
2354 return (result);
2355 }
2356
2357 signal(SIGALRM, timeout);
2358 if (setjmp(timebuf)) {
2359 close(s); /* not: fclose(fp) */
2360 return (result);
2361 }
2362 alarm(TIMEOUT);
2363
2364 /* Connect to the RFC931 daemon. */
2365
2366 memcpy(&sin, there, there->sa_len);
2367 switch (sin.ss_family) {
2368 case AF_INET:
2369 ((struct sockaddr_in *)&sin)->sin_port = htons(RFC931_PORT);
2370 break;
2371 #ifdef INET6
2372 case AF_INET6:
2373 ((struct sockaddr_in6 *)&sin)->sin6_port = htons(RFC931_PORT);
2374 break;
2375 #endif
2376 }
2377 if (connect(s, (struct sockaddr *) &sin, sin.ss_len) == -1) {
2378 close(s);
2379 alarm(0);
2380 return (result);
2381 }
2382
2383 /* Query the RFC 931 server. Would 13-byte writes ever be broken up? */
2384 (void)snprintf(buf, sizeof buf, "%u,%u\r\n", ntohs(hisport),
2385 ntohs(myport));
2386
2387 for (len = 0, cp = buf; len < strlen(buf); ) {
2388 int n;
2389
2390 if ((n = write(s, cp, strlen(buf) - len)) == -1) {
2391 close(s);
2392 alarm(0);
2393 return (result);
2394 }
2395 cp += n;
2396 len += n;
2397 }
2398
2399 /* Read response */
2400 for (cp = buf; cp < buf + sizeof(buf) - 1; ) {
2401 char c;
2402 if (read(s, &c, 1) != 1) {
2403 close(s);
2404 alarm(0);
2405 return (result);
2406 }
2407 if (c == '\n')
2408 break;
2409 *cp++ = c;
2410 }
2411 *cp = '\0';
2412
2413 if (sscanf(buf, "%u , %u : USERID :%*[^:]:%255s", &remote, &local,
2414 user) == 3 && ntohs(hisport) == remote && ntohs(myport) == local) {
2415 /* Strip trailing carriage return. */
2416 if ((cp = strchr(user, '\r')) != NULL)
2417 *cp = 0;
2418 result = user;
2419 }
2420
2421 alarm(0);
2422 close(s);
2423 return (result);
2424 }
2425 #endif
2426
2427 /*
2428 * check if the address/port where send data to is one of the obvious ports
2429 * that are used for denial of service attacks like two echo ports
2430 * just echoing data between them
2431 */
2432 static int
2433 port_good_dg(struct sockaddr *sa)
2434 {
2435 struct in_addr in;
2436 #ifdef INET6
2437 struct in6_addr *in6;
2438 #endif
2439 u_int16_t port;
2440 int i, bad;
2441 char hbuf[NI_MAXHOST];
2442
2443 bad = 0;
2444
2445 switch (sa->sa_family) {
2446 case AF_INET:
2447 in.s_addr = ntohl(((struct sockaddr_in *)sa)->sin_addr.s_addr);
2448 port = ntohs(((struct sockaddr_in *)sa)->sin_port);
2449 #ifdef INET6
2450 v4chk:
2451 #endif
2452 if (IN_MULTICAST(in.s_addr))
2453 goto bad;
2454 switch ((in.s_addr & 0xff000000) >> 24) {
2455 case 0: case 127: case 255:
2456 goto bad;
2457 }
2458 if (dg_broadcast(&in))
2459 goto bad;
2460 break;
2461 #ifdef INET6
2462 case AF_INET6:
2463 in6 = &((struct sockaddr_in6 *)sa)->sin6_addr;
2464 port = ntohs(((struct sockaddr_in6 *)sa)->sin6_port);
2465 if (IN6_IS_ADDR_MULTICAST(in6) || IN6_IS_ADDR_UNSPECIFIED(in6))
2466 goto bad;
2467 if (IN6_IS_ADDR_V4MAPPED(in6) || IN6_IS_ADDR_V4COMPAT(in6)) {
2468 memcpy(&in, &in6->s6_addr[12], sizeof(in));
2469 in.s_addr = ntohl(in.s_addr);
2470 goto v4chk;
2471 }
2472 break;
2473 #endif
2474 default:
2475 /* XXX unsupported af, is it safe to assume it to be safe? */
2476 return (1);
2477 }
2478
2479 for (i = 0; bad_ports[i] != 0; i++) {
2480 if (port == bad_ports[i])
2481 goto bad;
2482 }
2483
2484 return (1);
2485
2486 bad:
2487 if (getnameinfo(sa, sa->sa_len, hbuf, sizeof(hbuf), NULL, 0,
2488 niflags) != 0)
2489 strlcpy(hbuf, "?", sizeof(hbuf));
2490 syslog(LOG_WARNING,"Possible DoS attack from %s, Port %d",
2491 hbuf, port);
2492 return (0);
2493 }
2494
2495 /* XXX need optimization */
2496 static int
2497 dg_broadcast(struct in_addr *in)
2498 {
2499 struct ifaddrs *ifa, *ifap;
2500 struct sockaddr_in *sin;
2501
2502 if (getifaddrs(&ifap) < 0)
2503 return (0);
2504 for (ifa = ifap; ifa; ifa = ifa->ifa_next) {
2505 if (ifa->ifa_addr->sa_family != AF_INET ||
2506 (ifa->ifa_flags & IFF_BROADCAST) == 0)
2507 continue;
2508 sin = (struct sockaddr_in *)ifa->ifa_broadaddr;
2509 if (sin->sin_addr.s_addr == in->s_addr) {
2510 freeifaddrs(ifap);
2511 return (1);
2512 }
2513 }
2514 freeifaddrs(ifap);
2515 return (0);
2516 }
2517
2518 static int
2519 my_kevent(const struct kevent *changelist, size_t nchanges,
2520 struct kevent *eventlist, size_t nevents)
2521 {
2522 int result;
2523
2524 while ((result = kevent(kq, changelist, nchanges, eventlist, nevents,
2525 NULL)) < 0)
2526 if (errno != EINTR) {
2527 syslog(LOG_ERR, "kevent: %m");
2528 exit(EXIT_FAILURE);
2529 }
2530
2531 return (result);
2532 }
2533
2534 static struct kevent *
2535 allocchange(void)
2536 {
2537 if (changes == A_CNT(changebuf)) {
2538 (void) my_kevent(changebuf, A_CNT(changebuf), NULL, 0);
2539 changes = 0;
2540 }
2541
2542 return (&changebuf[changes++]);
2543 }
2544