source: MondoRescue/branches/2.2.5/mindi-busybox/networking/inetd.c@ 1765

Last change on this file since 1765 was 1765, checked in by Bruno Cornec, 16 years ago

Update to busybox 1.7.2
File size: 46.4 KB
Line 
1/* vi: set sw=4 ts=4: */
2/* $Slackware: inetd.c 1.79s 2001/02/06 13:18:00 volkerdi Exp $ */
3/* $OpenBSD: inetd.c,v 1.79 2001/01/30 08:30:57 deraadt Exp $ */
4/* $NetBSD: inetd.c,v 1.11 1996/02/22 11:14:41 mycroft Exp $ */
5/* Busybox port by Vladimir Oleynik (C) 2001-2005 <dzo@simtreas.ru> */
6/*
7 * Copyright (c) 1983,1991 The Regents of the University of California.
8 * All rights reserved.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. All advertising materials mentioning features or use of this software
19 * must display the following acknowledgement:
20 * This product includes software developed by the University of
21 * California, Berkeley and its contributors.
22 * 4. Neither the name of the University nor the names of its contributors
23 * may be used to endorse or promote products derived from this software
24 * without specific prior written permission.
25 *
26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS "AS IS" AND
27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 * SUCH DAMAGE.
37 */
38
39/* Inetd - Internet super-server
40 *
41 * This program invokes all internet services as needed.
42 * connection-oriented services are invoked each time a
43 * connection is made, by creating a process. This process
44 * is passed the connection as file descriptor 0 and is
45 * expected to do a getpeername to find out the source host
46 * and port.
47 *
48 * Datagram oriented services are invoked when a datagram
49 * arrives; a process is created and passed a pending message
50 * on file descriptor 0. Datagram servers may either connect
51 * to their peer, freeing up the original socket for inetd
52 * to receive further messages on, or "take over the socket",
53 * processing all arriving datagrams and, eventually, timing
54 * out. The first type of server is said to be "multi-threaded";
55 * the second type of server "single-threaded".
56 *
57 * Inetd uses a configuration file which is read at startup
58 * and, possibly, at some later time in response to a hangup signal.
59 * The configuration file is "free format" with fields given in the
60 * order shown below. Continuation lines for an entry must begin with
61 * a space or tab. All fields must be present in each entry.
62 *
63 * service name must be in /etc/services
64 * socket type stream/dgram/raw/rdm/seqpacket
65 * protocol must be in /etc/protocols
66 * wait/nowait[.max] single-threaded/multi-threaded, max #
67 * user[.group] or user[:group] user/group to run daemon as
68 * server program full path name
69 * server program arguments maximum of MAXARGS (20)
70 *
71 * For RPC services
72 * service name/version must be in /etc/rpc
73 * socket type stream/dgram/raw/rdm/seqpacket
74 * protocol must be in /etc/protocols
75 * wait/nowait[.max] single-threaded/multi-threaded
76 * user[.group] or user[:group] user to run daemon as
77 * server program full path name
78 * server program arguments maximum of MAXARGS (20)
79 *
80 * For non-RPC services, the "service name" can be of the form
81 * hostaddress:servicename, in which case the hostaddress is used
82 * as the host portion of the address to listen on. If hostaddress
83 * consists of a single `*' character, INADDR_ANY is used.
84 *
85 * A line can also consist of just
86 * hostaddress:
87 * where hostaddress is as in the preceding paragraph. Such a line must
88 * have no further fields; the specified hostaddress is remembered and
89 * used for all further lines that have no hostaddress specified,
90 * until the next such line (or EOF). (This is why * is provided to
91 * allow explicit specification of INADDR_ANY.) A line
92 * *:
93 * is implicitly in effect at the beginning of the file.
94 *
95 * The hostaddress specifier may (and often will) contain dots;
96 * the service name must not.
97 *
98 * For RPC services, host-address specifiers are accepted and will
99 * work to some extent; however, because of limitations in the
100 * portmapper interface, it will not work to try to give more than
101 * one line for any given RPC service, even if the host-address
102 * specifiers are different.
103 *
104 * Comment lines are indicated by a `#' in column 1.
105 */
106
107/* inetd rules for passing file descriptors to children
108 * (http://www.freebsd.org/cgi/man.cgi?query=inetd):
109 *
110 * The wait/nowait entry specifies whether the server that is invoked by
111 * inetd will take over the socket associated with the service access point,
112 * and thus whether inetd should wait for the server to exit before listen-
113 * ing for new service requests. Datagram servers must use "wait", as
114 * they are always invoked with the original datagram socket bound to the
115 * specified service address. These servers must read at least one datagram
116 * from the socket before exiting. If a datagram server connects to its
117 * peer, freeing the socket so inetd can receive further messages on the
118 * socket, it is said to be a "multi-threaded" server; it should read one
119 * datagram from the socket and create a new socket connected to the peer.
120 * It should fork, and the parent should then exit to allow inetd to check
121 * for new service requests to spawn new servers. Datagram servers which
122 * process all incoming datagrams on a socket and eventually time out are
123 * said to be "single-threaded". The comsat(8), (biff(1)) and talkd(8)
124 * utilities are both examples of the latter type of datagram server. The
125 * tftpd(8) utility is an example of a multi-threaded datagram server.
126 *
127 * Servers using stream sockets generally are multi-threaded and use the
128 * "nowait" entry. Connection requests for these services are accepted by
129 * inetd, and the server is given only the newly-accepted socket connected
130 * to a client of the service. Most stream-based services operate in this
131 * manner. Stream-based servers that use "wait" are started with the lis-
132 * tening service socket, and must accept at least one connection request
133 * before exiting. Such a server would normally accept and process incoming
134 * connection requests until a timeout.
135 */
136
137/* Here's the scoop concerning the user[.:]group feature:
138 *
139 * 1) set-group-option off.
140 *
141 * a) user = root: NO setuid() or setgid() is done
142 *
143 * b) other: setgid(primary group as found in passwd)
144 * initgroups(name, primary group)
145 * setuid()
146 *
147 * 2) set-group-option on.
148 *
149 * a) user = root: setgid(specified group)
150 * NO initgroups()
151 * NO setuid()
152 *
153 * b) other: setgid(specified group)
154 * initgroups(name, specified group)
155 * setuid()
156 */
157
158#include "libbb.h"
159#include <syslog.h>
160#include <sys/un.h>
161
162//#define ENABLE_FEATURE_INETD_RPC 1
163//#define ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_ECHO 1
164//#define ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DISCARD 1
165//#define ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_TIME 1
166//#define ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DAYTIME 1
167//#define ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_CHARGEN 1
168//#define ENABLE_FEATURE_IPV6 1
169
170#if ENABLE_FEATURE_INETD_RPC
171#include <rpc/rpc.h>
172#include <rpc/pmap_clnt.h>
173#endif
174
175extern char **environ;
176
177
178#define _PATH_INETDPID "/var/run/inetd.pid"
179
180#define CNT_INTVL 60 /* servers in CNT_INTVL sec. */
181#define RETRYTIME (60*10) /* retry after bind or server fail */
182
183#ifndef RLIMIT_NOFILE
184#define RLIMIT_NOFILE RLIMIT_OFILE
185#endif
186
187#ifndef OPEN_MAX
188#define OPEN_MAX 64
189#endif
190
191/* Reserve some descriptors, 3 stdio + at least: 1 log, 1 conf. file */
192#define FD_MARGIN 8
193static rlim_t rlim_ofile_cur = OPEN_MAX;
194static struct rlimit rlim_ofile;
195
196
197/* Check unsupporting builtin */
198#if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_ECHO || \
199 ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DISCARD || \
200 ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_TIME || \
201 ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DAYTIME || \
202 ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_CHARGEN
203# define INETD_FEATURE_ENABLED
204#endif
205
206#if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_ECHO || \
207 ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DISCARD || \
208 ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_CHARGEN
209# define INETD_SETPROCTITLE
210#endif
211
212typedef struct servtab {
213 char *se_hostaddr; /* host address to listen on */
214 char *se_service; /* name of service */
215 int se_socktype; /* type of socket to use */
216 int se_family; /* address family */
217 char *se_proto; /* protocol used */
218#if ENABLE_FEATURE_INETD_RPC
219 int se_rpcprog; /* rpc program number */
220 int se_rpcversl; /* rpc program lowest version */
221 int se_rpcversh; /* rpc program highest version */
222#define isrpcservice(sep) ((sep)->se_rpcversl != 0)
223#else
224#define isrpcservice(sep) 0
225#endif
226 pid_t se_wait; /* single threaded server */
227 short se_checked; /* looked at during merge */
228 char *se_user; /* user name to run as */
229 char *se_group; /* group name to run as */
230#ifdef INETD_FEATURE_ENABLED
231 const struct builtin *se_bi; /* if built-in, description */
232#endif
233 char *se_server; /* server program */
234#define MAXARGV 20
235 char *se_argv[MAXARGV + 1]; /* program arguments */
236 int se_fd; /* open descriptor */
237 union {
238 struct sockaddr se_un_ctrladdr;
239 struct sockaddr_in se_un_ctrladdr_in;
240#if ENABLE_FEATURE_IPV6
241 struct sockaddr_in6 se_un_ctrladdr_in6;
242#endif
243 struct sockaddr_un se_un_ctrladdr_un;
244 } se_un; /* bound address */
245#define se_ctrladdr se_un.se_un_ctrladdr
246#define se_ctrladdr_in se_un.se_un_ctrladdr_in
247#define se_ctrladdr_in6 se_un.se_un_ctrladdr_in6
248#define se_ctrladdr_un se_un.se_un_ctrladdr_un
249 int se_ctrladdr_size;
250 int se_max; /* max # of instances of this service */
251 int se_count; /* number started since se_time */
252 struct timeval se_time; /* start of se_count */
253 struct servtab *se_next;
254} servtab_t;
255
256static servtab_t *servtab;
257
258#ifdef INETD_FEATURE_ENABLED
259struct builtin {
260 const char *bi_service; /* internally provided service name */
261 int bi_socktype; /* type of socket supported */
262 short bi_fork; /* 1 if should fork before call */
263 short bi_wait; /* 1 if should wait for child */
264 void (*bi_fn) (int, servtab_t *);
265};
266
267 /* Echo received data */
268#if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_ECHO
269static void echo_stream(int, servtab_t *);
270static void echo_dg(int, servtab_t *);
271#endif
272 /* Internet /dev/null */
273#if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DISCARD
274static void discard_stream(int, servtab_t *);
275static void discard_dg(int, servtab_t *);
276#endif
277 /* Return 32 bit time since 1900 */
278#if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_TIME
279static void machtime_stream(int, servtab_t *);
280static void machtime_dg(int, servtab_t *);
281#endif
282 /* Return human-readable time */
283#if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DAYTIME
284static void daytime_stream(int, servtab_t *);
285static void daytime_dg(int, servtab_t *);
286#endif
287 /* Familiar character generator */
288#if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_CHARGEN
289static void chargen_stream(int, servtab_t *);
290static void chargen_dg(int, servtab_t *);
291#endif
292
293static const struct builtin builtins[] = {
294#if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_ECHO
295 /* Echo received data */
296 {"echo", SOCK_STREAM, 1, 0, echo_stream,},
297 {"echo", SOCK_DGRAM, 0, 0, echo_dg,},
298#endif
299#if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DISCARD
300 /* Internet /dev/null */
301 {"discard", SOCK_STREAM, 1, 0, discard_stream,},
302 {"discard", SOCK_DGRAM, 0, 0, discard_dg,},
303#endif
304#if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_TIME
305 /* Return 32 bit time since 1900 */
306 {"time", SOCK_STREAM, 0, 0, machtime_stream,},
307 {"time", SOCK_DGRAM, 0, 0, machtime_dg,},
308#endif
309#if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DAYTIME
310 /* Return human-readable time */
311 {"daytime", SOCK_STREAM, 0, 0, daytime_stream,},
312 {"daytime", SOCK_DGRAM, 0, 0, daytime_dg,},
313#endif
314#if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_CHARGEN
315 /* Familiar character generator */
316 {"chargen", SOCK_STREAM, 1, 0, chargen_stream,},
317 {"chargen", SOCK_DGRAM, 0, 0, chargen_dg,},
318#endif
319 {NULL, 0, 0, 0, NULL}
320};
321#endif /* INETD_FEATURE_ENABLED */
322
323static int global_queuelen = 128;
324static int nsock, maxsock;
325static fd_set allsock;
326static int toomany;
327static int timingout;
328static struct servent *sp;
329static uid_t uid;
330
331static const char *config_filename = "/etc/inetd.conf";
332
333static FILE *fconfig;
334static char *defhost;
335
336/* xstrdup(NULL) returns NULL, but this one
337 * will return newly-allocated "" if called with NULL arg
338 * TODO: audit whether this makes any real difference
339 */
340static char *xxstrdup(char *cp)
341{
342 return xstrdup(cp ? cp : "");
343}
344
345static int setconfig(void)
346{
347 free(defhost);
348 defhost = xstrdup("*");
349 if (fconfig != NULL) {
350 fseek(fconfig, 0L, SEEK_SET);
351 return 1;
352 }
353 fconfig = fopen(config_filename, "r");
354 return (fconfig != NULL);
355}
356
357static void endconfig(void)
358{
359 if (fconfig) {
360 (void) fclose(fconfig);
361 fconfig = NULL;
362 }
363 free(defhost);
364 defhost = 0;
365}
366
367#if ENABLE_FEATURE_INETD_RPC
368static void register_rpc(servtab_t *sep)
369{
370 int n;
371 struct sockaddr_in ir_sin;
372 struct protoent *pp;
373 socklen_t size;
374
375 if ((pp = getprotobyname(sep->se_proto + 4)) == NULL) {
376 bb_perror_msg("%s: getproto", sep->se_proto);
377 return;
378 }
379 size = sizeof ir_sin;
380 if (getsockname(sep->se_fd, (struct sockaddr *) &ir_sin, &size) < 0) {
381 bb_perror_msg("%s/%s: getsockname",
382 sep->se_service, sep->se_proto);
383 return;
384 }
385
386 for (n = sep->se_rpcversl; n <= sep->se_rpcversh; n++) {
387 (void) pmap_unset(sep->se_rpcprog, n);
388 if (!pmap_set(sep->se_rpcprog, n, pp->p_proto, ntohs(ir_sin.sin_port)))
389 bb_perror_msg("%s %s: pmap_set: %u %u %u %u",
390 sep->se_service, sep->se_proto,
391 sep->se_rpcprog, n, pp->p_proto, ntohs(ir_sin.sin_port));
392 }
393}
394
395static void unregister_rpc(servtab_t *sep)
396{
397 int n;
398
399 for (n = sep->se_rpcversl; n <= sep->se_rpcversh; n++) {
400 if (!pmap_unset(sep->se_rpcprog, n))
401 bb_error_msg("pmap_unset(%u, %u)", sep->se_rpcprog, n);
402 }
403}
404#endif /* FEATURE_INETD_RPC */
405
406static void freeconfig(servtab_t *cp)
407{
408 int i;
409
410 free(cp->se_hostaddr);
411 free(cp->se_service);
412 free(cp->se_proto);
413 free(cp->se_user);
414 free(cp->se_group);
415 free(cp->se_server);
416 for (i = 0; i < MAXARGV; i++)
417 free(cp->se_argv[i]);
418}
419
420static int bump_nofile(void)
421{
422#define FD_CHUNK 32
423
424 struct rlimit rl;
425
426 if (getrlimit(RLIMIT_NOFILE, &rl) < 0) {
427 bb_perror_msg("getrlimit");
428 return -1;
429 }
430 rl.rlim_cur = MIN(rl.rlim_max, rl.rlim_cur + FD_CHUNK);
431 rl.rlim_cur = MIN(FD_SETSIZE, rl.rlim_cur + FD_CHUNK);
432 if (rl.rlim_cur <= rlim_ofile_cur) {
433 bb_error_msg("bump_nofile: cannot extend file limit, max = %d",
434 (int) rl.rlim_cur);
435 return -1;
436 }
437
438 if (setrlimit(RLIMIT_NOFILE, &rl) < 0) {
439 bb_perror_msg("setrlimit");
440 return -1;
441 }
442
443 rlim_ofile_cur = rl.rlim_cur;
444 return 0;
445}
446
447static void setup(servtab_t *sep)
448{
449 int r;
450
451 sep->se_fd = socket(sep->se_family, sep->se_socktype, 0);
452 if (sep->se_fd < 0) {
453 bb_perror_msg("%s/%s: socket", sep->se_service, sep->se_proto);
454 return;
455 }
456 setsockopt_reuseaddr(sep->se_fd);
457
458#if ENABLE_FEATURE_INETD_RPC
459 if (isrpcservice(sep)) {
460 struct passwd *pwd;
461
462 /*
463 * for RPC services, attempt to use a reserved port
464 * if they are going to be running as root.
465 *
466 * Also, zero out the port for all RPC services; let bind()
467 * find one.
468 */
469 sep->se_ctrladdr_in.sin_port = 0;
470 if (sep->se_user && (pwd = getpwnam(sep->se_user)) &&
471 pwd->pw_uid == 0 && uid == 0)
472 r = bindresvport(sep->se_fd, &sep->se_ctrladdr_in);
473 else {
474 r = bind(sep->se_fd, &sep->se_ctrladdr, sep->se_ctrladdr_size);
475 if (r == 0) {
476 socklen_t len = sep->se_ctrladdr_size;
477 int saveerrno = errno;
478
479 /* update se_ctrladdr_in.sin_port */
480 r = getsockname(sep->se_fd, &sep->se_ctrladdr, &len);
481 if (r <= 0)
482 errno = saveerrno;
483 }
484 }
485 } else
486#endif
487 r = bind(sep->se_fd, &sep->se_ctrladdr, sep->se_ctrladdr_size);
488 if (r < 0) {
489 bb_perror_msg("%s/%s (%d): bind",
490 sep->se_service, sep->se_proto, sep->se_ctrladdr.sa_family);
491 close(sep->se_fd);
492 sep->se_fd = -1;
493 if (!timingout) {
494 timingout = 1;
495 alarm(RETRYTIME);
496 }
497 return;
498 }
499 if (sep->se_socktype == SOCK_STREAM)
500 listen(sep->se_fd, global_queuelen);
501
502 FD_SET(sep->se_fd, &allsock);
503 nsock++;
504 if (sep->se_fd > maxsock) {
505 maxsock = sep->se_fd;
506 if ((rlim_t)maxsock > rlim_ofile_cur - FD_MARGIN)
507 bump_nofile();
508 }
509}
510
511static char *nextline(void)
512{
513#define line bb_common_bufsiz1
514
515 char *cp;
516 FILE *fd = fconfig;
517
518 if (fgets(line, sizeof(line), fd) == NULL)
519 return NULL;
520 cp = strchr(line, '\n');
521 if (cp)
522 *cp = '\0';
523 return line;
524}
525
526static char *skip(char **cpp) /* int report; */
527{
528 char *cp = *cpp;
529 char *start;
530
531/* erp: */
532 if (*cpp == NULL) {
533 /* if (report) */
534 /* bb_error_msg("syntax error in inetd config file"); */
535 return NULL;
536 }
537
538 again:
539 while (*cp == ' ' || *cp == '\t')
540 cp++;
541 if (*cp == '\0') {
542 int c;
543
544 c = getc(fconfig);
545 ungetc(c, fconfig);
546 if (c == ' ' || c == '\t') {
547 cp = nextline();
548 if (cp)
549 goto again;
550 }
551 *cpp = NULL;
552 /* goto erp; */
553 return NULL;
554 }
555 start = cp;
556 while (*cp && *cp != ' ' && *cp != '\t')
557 cp++;
558 if (*cp != '\0')
559 *cp++ = '\0';
560 /* if ((*cpp = cp) == NULL) */
561 /* goto erp; */
562
563 *cpp = cp;
564 return start;
565}
566
567static servtab_t *new_servtab(void)
568{
569 return xmalloc(sizeof(servtab_t));
570}
571
572static servtab_t *dupconfig(servtab_t *sep)
573{
574 servtab_t *newtab;
575 int argc;
576
577 newtab = new_servtab();
578 memset(newtab, 0, sizeof(servtab_t));
579 newtab->se_service = xstrdup(sep->se_service);
580 newtab->se_socktype = sep->se_socktype;
581 newtab->se_family = sep->se_family;
582 newtab->se_proto = xstrdup(sep->se_proto);
583#if ENABLE_FEATURE_INETD_RPC
584 newtab->se_rpcprog = sep->se_rpcprog;
585 newtab->se_rpcversl = sep->se_rpcversl;
586 newtab->se_rpcversh = sep->se_rpcversh;
587#endif
588 newtab->se_wait = sep->se_wait;
589 newtab->se_user = xstrdup(sep->se_user);
590 newtab->se_group = xstrdup(sep->se_group);
591#ifdef INETD_FEATURE_ENABLED
592 newtab->se_bi = sep->se_bi;
593#endif
594 newtab->se_server = xstrdup(sep->se_server);
595
596 for (argc = 0; argc <= MAXARGV; argc++)
597 newtab->se_argv[argc] = xstrdup(sep->se_argv[argc]);
598 newtab->se_max = sep->se_max;
599
600 return newtab;
601}
602
603static servtab_t *getconfigent(void)
604{
605 servtab_t *sep;
606 int argc;
607 char *cp, *arg;
608 char *hostdelim;
609 servtab_t *nsep;
610 servtab_t *psep;
611
612 sep = new_servtab();
613
614 /* memset(sep, 0, sizeof *sep); */
615 more:
616 /* freeconfig(sep); */
617
618 while ((cp = nextline()) && *cp == '#') /* skip comment line */;
619 if (cp == NULL) {
620 /* free(sep); */
621 return NULL;
622 }
623
624 memset((char *) sep, 0, sizeof *sep);
625 arg = skip(&cp);
626 if (arg == NULL) {
627 /* A blank line. */
628 goto more;
629 }
630
631 /* Check for a host name. */
632 hostdelim = strrchr(arg, ':');
633 if (hostdelim) {
634 *hostdelim = '\0';
635 sep->se_hostaddr = xstrdup(arg);
636 arg = hostdelim + 1;
637 /*
638 * If the line is of the form `host:', then just change the
639 * default host for the following lines.
640 */
641 if (*arg == '\0') {
642 arg = skip(&cp);
643 if (cp == NULL) {
644 free(defhost);
645 defhost = sep->se_hostaddr;
646 goto more;
647 }
648 }
649 } else
650 sep->se_hostaddr = xxstrdup(defhost);
651
652 sep->se_service = xxstrdup(arg);
653 arg = skip(&cp);
654
655 if (strcmp(arg, "stream") == 0)
656 sep->se_socktype = SOCK_STREAM;
657 else if (strcmp(arg, "dgram") == 0)
658 sep->se_socktype = SOCK_DGRAM;
659 else if (strcmp(arg, "rdm") == 0)
660 sep->se_socktype = SOCK_RDM;
661 else if (strcmp(arg, "seqpacket") == 0)
662 sep->se_socktype = SOCK_SEQPACKET;
663 else if (strcmp(arg, "raw") == 0)
664 sep->se_socktype = SOCK_RAW;
665 else
666 sep->se_socktype = -1;
667
668 sep->se_proto = xxstrdup(skip(&cp));
669
670 if (strcmp(sep->se_proto, "unix") == 0) {
671 sep->se_family = AF_UNIX;
672 } else {
673 sep->se_family = AF_INET;
674 if (sep->se_proto[strlen(sep->se_proto) - 1] == '6')
675#if ENABLE_FEATURE_IPV6
676 sep->se_family = AF_INET6;
677#else
678 bb_error_msg("%s: IPV6 not supported", sep->se_proto);
679#endif
680 if (strncmp(sep->se_proto, "rpc/", 4) == 0) {
681#if ENABLE_FEATURE_INETD_RPC
682 char *p, *ccp;
683 long l;
684
685 p = strchr(sep->se_service, '/');
686 if (p == 0) {
687 bb_error_msg("%s: no rpc version", sep->se_service);
688 goto more;
689 }
690 *p++ = '\0';
691 l = strtol(p, &ccp, 0);
692 if (ccp == p || l < 0 || l > INT_MAX) {
693 badafterall:
694 bb_error_msg("%s/%s: bad rpc version", sep->se_service, p);
695 goto more;
696 }
697 sep->se_rpcversl = sep->se_rpcversh = l;
698 if (*ccp == '-') {
699 p = ccp + 1;
700 l = strtol(p, &ccp, 0);
701 if (ccp == p || l < 0 || l > INT_MAX || l < sep->se_rpcversl || *ccp)
702 goto badafterall;
703 sep->se_rpcversh = l;
704 } else if (*ccp != '\0')
705 goto badafterall;
706#else
707 bb_error_msg("%s: rpc services not supported", sep->se_service);
708#endif
709 }
710 }
711 arg = skip(&cp);
712 if (arg == NULL)
713 goto more;
714
715 {
716 char *s = strchr(arg, '.');
717 if (s) {
718 *s++ = '\0';
719 sep->se_max = xatoi(s);
720 } else
721 sep->se_max = toomany;
722 }
723 sep->se_wait = strcmp(arg, "wait") == 0;
724 /* if ((arg = skip(&cp, 1)) == NULL) */
725 /* goto more; */
726 sep->se_user = xxstrdup(skip(&cp));
727 arg = strchr(sep->se_user, '.');
728 if (arg == NULL)
729 arg = strchr(sep->se_user, ':');
730 if (arg) {
731 *arg++ = '\0';
732 sep->se_group = xstrdup(arg);
733 }
734 /* if ((arg = skip(&cp, 1)) == NULL) */
735 /* goto more; */
736
737 sep->se_server = xxstrdup(skip(&cp));
738 if (strcmp(sep->se_server, "internal") == 0) {
739#ifdef INETD_FEATURE_ENABLED
740 const struct builtin *bi;
741
742 for (bi = builtins; bi->bi_service; bi++)
743 if (bi->bi_socktype == sep->se_socktype &&
744 strcmp(bi->bi_service, sep->se_service) == 0)
745 break;
746 if (bi->bi_service == 0) {
747 bb_error_msg("internal service %s unknown", sep->se_service);
748 goto more;
749 }
750 sep->se_bi = bi;
751 sep->se_wait = bi->bi_wait;
752#else
753 bb_perror_msg("internal service %s unknown", sep->se_service);
754 goto more;
755#endif
756 }
757#ifdef INETD_FEATURE_ENABLED
758 else
759 sep->se_bi = NULL;
760#endif
761 argc = 0;
762 for (arg = skip(&cp); cp; arg = skip(&cp)) {
763 if (argc < MAXARGV)
764 sep->se_argv[argc++] = xxstrdup(arg);
765 }
766 while (argc <= MAXARGV)
767 sep->se_argv[argc++] = NULL;
768
769 /*
770 * Now that we've processed the entire line, check if the hostname
771 * specifier was a comma separated list of hostnames. If so
772 * we'll make new entries for each address.
773 */
774 while ((hostdelim = strrchr(sep->se_hostaddr, ',')) != NULL) {
775 nsep = dupconfig(sep);
776
777 /*
778 * NULL terminate the hostname field of the existing entry,
779 * and make a dup for the new entry.
780 */
781 *hostdelim++ = '\0';
782 nsep->se_hostaddr = xstrdup(hostdelim);
783
784 nsep->se_next = sep->se_next;
785 sep->se_next = nsep;
786 }
787
788 nsep = sep;
789 while (nsep != NULL) {
790 nsep->se_checked = 1;
791 if (nsep->se_family == AF_INET) {
792 if (LONE_CHAR(nsep->se_hostaddr, '*'))
793 nsep->se_ctrladdr_in.sin_addr.s_addr = INADDR_ANY;
794 else if (!inet_aton(nsep->se_hostaddr, &nsep->se_ctrladdr_in.sin_addr)) {
795 struct hostent *hp;
796
797 hp = gethostbyname(nsep->se_hostaddr);
798 if (hp == 0) {
799 bb_error_msg("%s: unknown host", nsep->se_hostaddr);
800 nsep->se_checked = 0;
801 goto skip;
802 } else if (hp->h_addrtype != AF_INET) {
803 bb_error_msg("%s: address isn't an Internet "
804 "address", nsep->se_hostaddr);
805 nsep->se_checked = 0;
806 goto skip;
807 } else {
808 int i = 1;
809
810 memmove(&nsep->se_ctrladdr_in.sin_addr,
811 hp->h_addr_list[0], sizeof(struct in_addr));
812 while (hp->h_addr_list[i] != NULL) {
813 psep = dupconfig(nsep);
814 psep->se_hostaddr = xxstrdup(nsep->se_hostaddr);
815 psep->se_checked = 1;
816 memmove(&psep->se_ctrladdr_in.sin_addr,
817 hp->h_addr_list[i], sizeof(struct in_addr));
818 psep->se_ctrladdr_size = sizeof(psep->se_ctrladdr_in);
819 i++;
820 /* Prepend to list, don't want to look up */
821 /* its hostname again. */
822 psep->se_next = sep;
823 sep = psep;
824 }
825 }
826 }
827 }
828/* XXX BUG?: is this skip: label supposed to remain? */
829 skip:
830 nsep = nsep->se_next;
831 }
832
833 /*
834 * Finally, free any entries which failed the gethostbyname
835 * check.
836 */
837 psep = NULL;
838 nsep = sep;
839 while (nsep != NULL) {
840 servtab_t *tsep;
841
842 if (nsep->se_checked == 0) {
843 tsep = nsep;
844 if (psep == NULL) {
845 sep = nsep->se_next;
846 nsep = sep;
847 } else {
848 nsep = nsep->se_next;
849 psep->se_next = nsep;
850 }
851 freeconfig(tsep);
852 } else {
853 nsep->se_checked = 0;
854 psep = nsep;
855 nsep = nsep->se_next;
856 }
857 }
858
859 return sep;
860}
861
862#define Block_Using_Signals(m) do { \
863 sigemptyset(&m); \
864 sigaddset(&m, SIGCHLD); \
865 sigaddset(&m, SIGHUP); \
866 sigaddset(&m, SIGALRM); \
867 sigprocmask(SIG_BLOCK, &m, NULL); \
868} while (0)
869
870static servtab_t *enter(servtab_t *cp)
871{
872 servtab_t *sep;
873 sigset_t omask;
874
875 sep = new_servtab();
876 *sep = *cp;
877 sep->se_fd = -1;
878#if ENABLE_FEATURE_INETD_RPC
879 sep->se_rpcprog = -1;
880#endif
881 Block_Using_Signals(omask);
882 sep->se_next = servtab;
883 servtab = sep;
884 sigprocmask(SIG_UNBLOCK, &omask, NULL);
885 return sep;
886}
887
888static int matchconf(servtab_t *old, servtab_t *new)
889{
890 if (strcmp(old->se_service, new->se_service) != 0)
891 return 0;
892
893 if (strcmp(old->se_hostaddr, new->se_hostaddr) != 0)
894 return 0;
895
896 if (strcmp(old->se_proto, new->se_proto) != 0)
897 return 0;
898
899 /*
900 * If the new servtab is bound to a specific address, check that the
901 * old servtab is bound to the same entry. If the new service is not
902 * bound to a specific address then the check of se_hostaddr above
903 * is sufficient.
904 */
905
906 if (old->se_family == AF_INET && new->se_family == AF_INET &&
907 memcmp(&old->se_ctrladdr_in.sin_addr,
908 &new->se_ctrladdr_in.sin_addr,
909 sizeof(new->se_ctrladdr_in.sin_addr)) != 0)
910 return 0;
911
912#if ENABLE_FEATURE_IPV6
913 if (old->se_family == AF_INET6 && new->se_family == AF_INET6 &&
914 memcmp(&old->se_ctrladdr_in6.sin6_addr,
915 &new->se_ctrladdr_in6.sin6_addr,
916 sizeof(new->se_ctrladdr_in6.sin6_addr)) != 0)
917 return 0;
918#endif
919 return 1;
920}
921
922static void config(int sig ATTRIBUTE_UNUSED)
923{
924 servtab_t *sep, *cp, **sepp;
925 sigset_t omask;
926 size_t n;
927 char protoname[10];
928
929 if (!setconfig()) {
930 bb_perror_msg("%s", config_filename);
931 return;
932 }
933 for (sep = servtab; sep; sep = sep->se_next)
934 sep->se_checked = 0;
935 cp = getconfigent();
936 while (cp != NULL) {
937 for (sep = servtab; sep; sep = sep->se_next)
938 if (matchconf(sep, cp))
939 break;
940
941 if (sep != 0) {
942 int i;
943
944#define SWAP(type, a, b) do {type c=(type)a; a=(type)b; b=(type)c;} while (0)
945
946 Block_Using_Signals(omask);
947 /*
948 * sep->se_wait may be holding the pid of a daemon
949 * that we're waiting for. If so, don't overwrite
950 * it unless the config file explicitly says don't
951 * wait.
952 */
953 if (
954#ifdef INETD_FEATURE_ENABLED
955 cp->se_bi == 0 &&
956#endif
957 (sep->se_wait == 1 || cp->se_wait == 0))
958 sep->se_wait = cp->se_wait;
959 SWAP(int, cp->se_max, sep->se_max);
960 SWAP(char *, sep->se_user, cp->se_user);
961 SWAP(char *, sep->se_group, cp->se_group);
962 SWAP(char *, sep->se_server, cp->se_server);
963 for (i = 0; i < MAXARGV; i++)
964 SWAP(char *, sep->se_argv[i], cp->se_argv[i]);
965#undef SWAP
966
967#if ENABLE_FEATURE_INETD_RPC
968 if (isrpcservice(sep))
969 unregister_rpc(sep);
970 sep->se_rpcversl = cp->se_rpcversl;
971 sep->se_rpcversh = cp->se_rpcversh;
972#endif
973 sigprocmask(SIG_UNBLOCK, &omask, NULL);
974 freeconfig(cp);
975 } else {
976 sep = enter(cp);
977 }
978 sep->se_checked = 1;
979
980 switch (sep->se_family) {
981 case AF_UNIX:
982 if (sep->se_fd != -1)
983 break;
984 (void) unlink(sep->se_service);
985 n = strlen(sep->se_service);
986 if (n > sizeof sep->se_ctrladdr_un.sun_path - 1)
987 n = sizeof sep->se_ctrladdr_un.sun_path - 1;
988 safe_strncpy(sep->se_ctrladdr_un.sun_path, sep->se_service, n + 1);
989 sep->se_ctrladdr_un.sun_family = AF_UNIX;
990 sep->se_ctrladdr_size = n + sizeof sep->se_ctrladdr_un.sun_family;
991 setup(sep);
992 break;
993 case AF_INET:
994 sep->se_ctrladdr_in.sin_family = AF_INET;
995 /* se_ctrladdr_in was set in getconfigent */
996 sep->se_ctrladdr_size = sizeof sep->se_ctrladdr_in;
997
998#if ENABLE_FEATURE_INETD_RPC
999 if (isrpcservice(sep)) {
1000 struct rpcent *rp;
1001 // FIXME: atoi_or_else(str, 0) would be handy here
1002 sep->se_rpcprog = atoi(sep->se_service);
1003 if (sep->se_rpcprog == 0) {
1004 rp = getrpcbyname(sep->se_service);
1005 if (rp == 0) {
1006 bb_error_msg("%s: unknown rpc service", sep->se_service);
1007 goto serv_unknown;
1008 }
1009 sep->se_rpcprog = rp->r_number;
1010 }
1011 if (sep->se_fd == -1)
1012 setup(sep);
1013 if (sep->se_fd != -1)
1014 register_rpc(sep);
1015 } else
1016#endif
1017 {
1018 uint16_t port = htons(atoi(sep->se_service));
1019 // FIXME: atoi_or_else(str, 0) would be handy here
1020 if (!port) {
1021 /*XXX*/ strncpy(protoname, sep->se_proto, sizeof(protoname));
1022 if (isdigit(protoname[strlen(protoname) - 1]))
1023 protoname[strlen(protoname) - 1] = '\0';
1024 sp = getservbyname(sep->se_service, protoname);
1025 if (sp == 0) {
1026 bb_error_msg("%s/%s: unknown service",
1027 sep->se_service, sep->se_proto);
1028 goto serv_unknown;
1029 }
1030 port = sp->s_port;
1031 }
1032 if (port != sep->se_ctrladdr_in.sin_port) {
1033 sep->se_ctrladdr_in.sin_port = port;
1034 if (sep->se_fd != -1) {
1035 FD_CLR(sep->se_fd, &allsock);
1036 nsock--;
1037 (void) close(sep->se_fd);
1038 }
1039 sep->se_fd = -1;
1040 }
1041 if (sep->se_fd == -1)
1042 setup(sep);
1043 }
1044 break;
1045#if ENABLE_FEATURE_IPV6
1046 case AF_INET6:
1047 sep->se_ctrladdr_in6.sin6_family = AF_INET6;
1048 /* se_ctrladdr_in was set in getconfigent */
1049 sep->se_ctrladdr_size = sizeof sep->se_ctrladdr_in6;
1050
1051#if ENABLE_FEATURE_INETD_RPC
1052 if (isrpcservice(sep)) {
1053 struct rpcent *rp;
1054
1055 sep->se_rpcprog = atoi(sep->se_service);
1056 if (sep->se_rpcprog == 0) {
1057 rp = getrpcbyname(sep->se_service);
1058 if (rp == 0) {
1059 bb_error_msg("%s: unknown rpc service", sep->se_service);
1060 goto serv_unknown;
1061 }
1062 sep->se_rpcprog = rp->r_number;
1063 }
1064 if (sep->se_fd == -1)
1065 setup(sep);
1066 if (sep->se_fd != -1)
1067 register_rpc(sep);
1068 } else
1069#endif
1070 {
1071 uint16_t port = htons(atoi(sep->se_service));
1072
1073 if (!port) {
1074 /*XXX*/ strncpy(protoname, sep->se_proto, sizeof(protoname));
1075 if (isdigit(protoname[strlen(protoname) - 1]))
1076 protoname[strlen(protoname) - 1] = '\0';
1077 sp = getservbyname(sep->se_service, protoname);
1078 if (sp == 0) {
1079 bb_error_msg("%s/%s: unknown service",
1080 sep->se_service, sep->se_proto);
1081 goto serv_unknown;
1082 }
1083 port = sp->s_port;
1084 }
1085 if (port != sep->se_ctrladdr_in6.sin6_port) {
1086 sep->se_ctrladdr_in6.sin6_port = port;
1087 if (sep->se_fd != -1) {
1088 FD_CLR(sep->se_fd, &allsock);
1089 nsock--;
1090 (void) close(sep->se_fd);
1091 }
1092 sep->se_fd = -1;
1093 }
1094 if (sep->se_fd == -1)
1095 setup(sep);
1096 }
1097 break;
1098#endif /* FEATURE_IPV6 */
1099 }
1100 serv_unknown:
1101 if (cp->se_next != NULL) {
1102 servtab_t *tmp = cp;
1103
1104 cp = cp->se_next;
1105 free(tmp);
1106 } else {
1107 free(cp);
1108 cp = getconfigent();
1109 }
1110 }
1111 endconfig();
1112 /*
1113 * Purge anything not looked at above.
1114 */
1115 Block_Using_Signals(omask);
1116 sepp = &servtab;
1117 while ((sep = *sepp)) {
1118 if (sep->se_checked) {
1119 sepp = &sep->se_next;
1120 continue;
1121 }
1122 *sepp = sep->se_next;
1123 if (sep->se_fd != -1) {
1124 FD_CLR(sep->se_fd, &allsock);
1125 nsock--;
1126 (void) close(sep->se_fd);
1127 }
1128#if ENABLE_FEATURE_INETD_RPC
1129 if (isrpcservice(sep))
1130 unregister_rpc(sep);
1131#endif
1132 if (sep->se_family == AF_UNIX)
1133 (void) unlink(sep->se_service);
1134 freeconfig(sep);
1135 free(sep);
1136 }
1137 sigprocmask(SIG_UNBLOCK, &omask, NULL);
1138}
1139
1140
1141static void reapchild(int sig ATTRIBUTE_UNUSED)
1142{
1143 pid_t pid;
1144 int save_errno = errno, status;
1145 servtab_t *sep;
1146
1147 for (;;) {
1148 pid = wait3(&status, WNOHANG, NULL);
1149 if (pid <= 0)
1150 break;
1151 for (sep = servtab; sep; sep = sep->se_next)
1152 if (sep->se_wait == pid) {
1153 if (WIFEXITED(status) && WEXITSTATUS(status))
1154 bb_error_msg("%s: exit status 0x%x",
1155 sep->se_server, WEXITSTATUS(status));
1156 else if (WIFSIGNALED(status))
1157 bb_error_msg("%s: exit signal 0x%x",
1158 sep->se_server, WTERMSIG(status));
1159 sep->se_wait = 1;
1160 FD_SET(sep->se_fd, &allsock);
1161 nsock++;
1162 }
1163 }
1164 errno = save_errno;
1165}
1166
1167static void retry(int sig ATTRIBUTE_UNUSED)
1168{
1169 servtab_t *sep;
1170
1171 timingout = 0;
1172 for (sep = servtab; sep; sep = sep->se_next) {
1173 if (sep->se_fd == -1) {
1174 switch (sep->se_family) {
1175 case AF_UNIX:
1176 case AF_INET:
1177#if ENABLE_FEATURE_IPV6
1178 case AF_INET6:
1179#endif
1180 setup(sep);
1181#if ENABLE_FEATURE_INETD_RPC
1182 if (sep->se_fd != -1 && isrpcservice(sep))
1183 register_rpc(sep);
1184#endif
1185 break;
1186 }
1187 }
1188 }
1189}
1190
1191static void goaway(int sig ATTRIBUTE_UNUSED)
1192{
1193 servtab_t *sep;
1194
1195 /* XXX signal race walking sep list */
1196 for (sep = servtab; sep; sep = sep->se_next) {
1197 if (sep->se_fd == -1)
1198 continue;
1199
1200 switch (sep->se_family) {
1201 case AF_UNIX:
1202 (void) unlink(sep->se_service);
1203 break;
1204 case AF_INET:
1205#if ENABLE_FEATURE_IPV6
1206 case AF_INET6:
1207#endif
1208#if ENABLE_FEATURE_INETD_RPC
1209 if (sep->se_wait == 1 && isrpcservice(sep))
1210 unregister_rpc(sep); /* XXX signal race */
1211#endif
1212 break;
1213 }
1214 (void) close(sep->se_fd);
1215 }
1216 remove_pidfile(_PATH_INETDPID);
1217 exit(0);
1218}
1219
1220
1221#ifdef INETD_SETPROCTITLE
1222static char **Argv;
1223static char *LastArg;
1224
1225static void
1226inetd_setproctitle(char *a, int s)
1227{
1228 socklen_t size;
1229 char *cp;
1230 struct sockaddr_in prt_sin;
1231 char buf[80];
1232
1233 cp = Argv[0];
1234 size = sizeof(prt_sin);
1235 (void) snprintf(buf, sizeof buf, "-%s", a);
1236 if (getpeername(s, (struct sockaddr *) &prt_sin, &size) == 0) {
1237 char *sa = inet_ntoa(prt_sin.sin_addr);
1238
1239 buf[sizeof(buf) - 1 - strlen(sa) - 3] = '\0';
1240 strcat(buf, " [");
1241 strcat(buf, sa);
1242 strcat(buf, "]");
1243 }
1244 strncpy(cp, buf, LastArg - cp);
1245 cp += strlen(cp);
1246 while (cp < LastArg)
1247 *cp++ = ' ';
1248}
1249#endif
1250
1251
1252int inetd_main(int argc, char **argv);
1253int inetd_main(int argc, char **argv)
1254{
1255 servtab_t *sep;
1256 struct passwd *pwd;
1257 struct group *grp = NULL;
1258 int tmpint;
1259 struct sigaction sa, sapipe;
1260 int opt;
1261 pid_t pid;
1262 char buf[50];
1263 char *stoomany;
1264 sigset_t omask, wait_mask;
1265
1266#ifdef INETD_SETPROCTITLE
1267 char **envp = environ;
1268
1269 Argv = argv;
1270 if (envp == 0 || *envp == 0)
1271 envp = argv;
1272 while (*envp)
1273 envp++;
1274 LastArg = envp[-1] + strlen(envp[-1]);
1275#endif
1276
1277 uid = getuid();
1278 if (uid != 0)
1279 config_filename = NULL;
1280
1281 opt = getopt32(argv, "R:f", &stoomany);
1282 if (opt & 1)
1283 toomany = xatoi_u(stoomany);
1284 argv += optind;
1285 argc -= optind;
1286 if (argc)
1287 config_filename = argv[0];
1288 if (config_filename == NULL)
1289 bb_error_msg_and_die("non-root must specify a config file");
1290
1291 if (!(opt & 2))
1292 bb_daemonize_or_rexec(0, argv - optind);
1293 else
1294 bb_sanitize_stdio();
1295 openlog(applet_name, LOG_PID | LOG_NOWAIT, LOG_DAEMON);
1296 logmode = LOGMODE_SYSLOG;
1297
1298 if (uid == 0) {
1299 /* If run by hand, ensure groups vector gets trashed */
1300 gid_t gid = getgid();
1301 setgroups(1, &gid);
1302 }
1303
1304 write_pidfile(_PATH_INETDPID);
1305
1306 if (getrlimit(RLIMIT_NOFILE, &rlim_ofile) < 0) {
1307 bb_perror_msg("getrlimit");
1308 } else {
1309 rlim_ofile_cur = rlim_ofile.rlim_cur;
1310 if (rlim_ofile_cur == RLIM_INFINITY) /* ! */
1311 rlim_ofile_cur = OPEN_MAX;
1312 }
1313
1314 memset((char *) &sa, 0, sizeof(sa));
1315 sigemptyset(&sa.sa_mask);
1316 sigaddset(&sa.sa_mask, SIGALRM);
1317 sigaddset(&sa.sa_mask, SIGCHLD);
1318 sigaddset(&sa.sa_mask, SIGHUP);
1319 sa.sa_handler = retry;
1320 sigaction(SIGALRM, &sa, NULL);
1321 config(SIGHUP);
1322 sa.sa_handler = config;
1323 sigaction(SIGHUP, &sa, NULL);
1324 sa.sa_handler = reapchild;
1325 sigaction(SIGCHLD, &sa, NULL);
1326 sa.sa_handler = goaway;
1327 sigaction(SIGTERM, &sa, NULL);
1328 sa.sa_handler = goaway;
1329 sigaction(SIGINT, &sa, NULL);
1330 sa.sa_handler = SIG_IGN;
1331 sigaction(SIGPIPE, &sa, &sapipe);
1332 memset(&wait_mask, 0, sizeof(wait_mask));
1333 {
1334 /* space for daemons to overwrite environment for ps */
1335#define DUMMYSIZE 100
1336 char dummy[DUMMYSIZE];
1337
1338 (void) memset(dummy, 'x', DUMMYSIZE - 1);
1339 dummy[DUMMYSIZE - 1] = '\0';
1340
1341 (void) setenv("inetd_dummy", dummy, 1);
1342 }
1343
1344 for (;;) {
1345 int n, ctrl = -1;
1346 fd_set readable;
1347
1348 if (nsock == 0) {
1349 Block_Using_Signals(omask);
1350 while (nsock == 0)
1351 sigsuspend(&wait_mask);
1352 sigprocmask(SIG_UNBLOCK, &omask, NULL);
1353 }
1354
1355 readable = allsock;
1356 n = select(maxsock + 1, &readable, NULL, NULL, NULL);
1357 if (n <= 0) {
1358 if (n < 0 && errno != EINTR) {
1359 bb_perror_msg("select");
1360 sleep(1);
1361 }
1362 continue;
1363 }
1364
1365 for (sep = servtab; n && sep; sep = sep->se_next) {
1366 if (sep->se_fd == -1 || !FD_ISSET(sep->se_fd, &readable))
1367 continue;
1368
1369 n--;
1370 if (!sep->se_wait && sep->se_socktype == SOCK_STREAM) {
1371 ctrl = accept(sep->se_fd, NULL, NULL);
1372 if (ctrl < 0) {
1373 if (errno == EINTR)
1374 continue;
1375 bb_perror_msg("accept (for %s)", sep->se_service);
1376 continue;
1377 }
1378 if (sep->se_family == AF_INET && sep->se_socktype == SOCK_STREAM) {
1379 struct sockaddr_in peer;
1380 socklen_t plen = sizeof(peer);
1381
1382 if (getpeername(ctrl, (struct sockaddr *) &peer, &plen) < 0) {
1383 bb_error_msg("cannot getpeername");
1384 close(ctrl);
1385 continue;
1386 }
1387 if (ntohs(peer.sin_port) == 20) {
1388 /* XXX ftp bounce */
1389 close(ctrl);
1390 continue;
1391 }
1392 }
1393 } else
1394 ctrl = sep->se_fd;
1395
1396 Block_Using_Signals(omask);
1397 pid = 0;
1398#ifdef INETD_FEATURE_ENABLED
1399 if (sep->se_bi == 0 || sep->se_bi->bi_fork)
1400#endif
1401 {
1402 if (sep->se_count++ == 0)
1403 (void) gettimeofday(&sep->se_time, NULL);
1404 else if (toomany > 0 && sep->se_count >= sep->se_max) {
1405 struct timeval now;
1406
1407 (void) gettimeofday(&now, NULL);
1408 if (now.tv_sec - sep->se_time.tv_sec > CNT_INTVL) {
1409 sep->se_time = now;
1410 sep->se_count = 1;
1411 } else {
1412 if (!sep->se_wait && sep->se_socktype == SOCK_STREAM)
1413 close(ctrl);
1414 if (sep->se_family == AF_INET &&
1415 ntohs(sep->se_ctrladdr_in.sin_port) >= IPPORT_RESERVED) {
1416 /*
1417 * Cannot close it -- there are
1418 * thieves on the system.
1419 * Simply ignore the connection.
1420 */
1421 --sep->se_count;
1422 continue;
1423 }
1424 bb_error_msg("%s/%s server failing (looping), service terminated",
1425 sep->se_service, sep->se_proto);
1426 if (!sep->se_wait && sep->se_socktype == SOCK_STREAM)
1427 close(ctrl);
1428 FD_CLR(sep->se_fd, &allsock);
1429 (void) close(sep->se_fd);
1430 sep->se_fd = -1;
1431 sep->se_count = 0;
1432 nsock--;
1433 sigprocmask(SIG_UNBLOCK, &omask, NULL);
1434 if (!timingout) {
1435 timingout = 1;
1436 alarm(RETRYTIME);
1437 }
1438 continue;
1439 }
1440 }
1441 pid = fork();
1442 }
1443 if (pid < 0) {
1444 bb_perror_msg("fork");
1445 if (!sep->se_wait && sep->se_socktype == SOCK_STREAM)
1446 close(ctrl);
1447 sigprocmask(SIG_UNBLOCK, &omask, NULL);
1448 sleep(1);
1449 continue;
1450 }
1451 if (pid && sep->se_wait) {
1452 sep->se_wait = pid;
1453 FD_CLR(sep->se_fd, &allsock);
1454 nsock--;
1455 }
1456 sigprocmask(SIG_UNBLOCK, &omask, NULL);
1457 if (pid == 0) {
1458#ifdef INETD_FEATURE_ENABLED
1459 if (sep->se_bi) {
1460 (*sep->se_bi->bi_fn)(ctrl, sep);
1461 } else
1462#endif
1463 {
1464 pwd = getpwnam(sep->se_user);
1465 if (pwd == NULL) {
1466 bb_error_msg("getpwnam: %s: no such user", sep->se_user);
1467 goto do_exit1;
1468 }
1469 if (setsid() < 0)
1470 bb_perror_msg("%s: setsid", sep->se_service);
1471 if (sep->se_group && (grp = getgrnam(sep->se_group)) == NULL) {
1472 bb_error_msg("getgrnam: %s: no such group", sep->se_group);
1473 goto do_exit1;
1474 }
1475 if (uid != 0) {
1476 /* a user running private inetd */
1477 if (uid != pwd->pw_uid)
1478 _exit(1);
1479 } else if (pwd->pw_uid) {
1480 if (sep->se_group)
1481 pwd->pw_gid = grp->gr_gid;
1482 xsetgid((gid_t) pwd->pw_gid);
1483 initgroups(pwd->pw_name, pwd->pw_gid);
1484 xsetuid((uid_t) pwd->pw_uid);
1485 } else if (sep->se_group) {
1486 xsetgid(grp->gr_gid);
1487 setgroups(1, &grp->gr_gid);
1488 }
1489 dup2(ctrl, 0);
1490 if (ctrl) close(ctrl);
1491 dup2(0, 1);
1492 dup2(0, 2);
1493 if (rlim_ofile.rlim_cur != rlim_ofile_cur)
1494 if (setrlimit(RLIMIT_NOFILE, &rlim_ofile) < 0)
1495 bb_perror_msg("setrlimit");
1496 closelog();
1497 for (tmpint = rlim_ofile_cur - 1; --tmpint > 2;)
1498 (void) close(tmpint);
1499 sigaction(SIGPIPE, &sapipe, NULL);
1500 execv(sep->se_server, sep->se_argv);
1501 bb_perror_msg("execv %s", sep->se_server);
1502 do_exit1:
1503 if (sep->se_socktype != SOCK_STREAM)
1504 recv(0, buf, sizeof(buf), 0);
1505 _exit(1);
1506 }
1507 }
1508 if (!sep->se_wait && sep->se_socktype == SOCK_STREAM)
1509 close(ctrl);
1510 } /* for (sep = servtab...) */
1511 } /* for (;;) */
1512}
1513
1514/*
1515 * Internet services provided internally by inetd:
1516 */
1517#define BUFSIZE 4096
1518
1519#if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_ECHO || \
1520 ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_CHARGEN || \
1521 ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DAYTIME
1522static int dg_badinput(struct sockaddr_in *dg_sin)
1523{
1524 if (ntohs(dg_sin->sin_port) < IPPORT_RESERVED)
1525 return 1;
1526 if (dg_sin->sin_addr.s_addr == htonl(INADDR_BROADCAST))
1527 return 1;
1528 /* XXX compare against broadcast addresses in SIOCGIFCONF list? */
1529 return 0;
1530}
1531#endif
1532
1533#if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_ECHO
1534/* Echo service -- echo data back */
1535/* ARGSUSED */
1536static void
1537echo_stream(int s, servtab_t *sep)
1538{
1539 char buffer[BUFSIZE];
1540 int i;
1541
1542 inetd_setproctitle(sep->se_service, s);
1543 while (1) {
1544 i = read(s, buffer, sizeof(buffer));
1545 if (i <= 0) break;
1546 /* FIXME: this isnt correct - safe_write()? */
1547 if (write(s, buffer, i) <= 0) break;
1548 }
1549 exit(0);
1550}
1551
1552/* Echo service -- echo data back */
1553/* ARGSUSED */
1554static void
1555echo_dg(int s, servtab_t *sep ATTRIBUTE_UNUSED)
1556{
1557 char buffer[BUFSIZE];
1558 int i;
1559 socklen_t size;
1560 /* struct sockaddr_storage ss; */
1561 struct sockaddr sa;
1562
1563 size = sizeof(sa);
1564 i = recvfrom(s, buffer, sizeof(buffer), 0, &sa, &size);
1565 if (i < 0)
1566 return;
1567 if (dg_badinput((struct sockaddr_in *) &sa))
1568 return;
1569 (void) sendto(s, buffer, i, 0, &sa, sizeof(sa));
1570}
1571#endif /* FEATURE_INETD_SUPPORT_BUILTIN_ECHO */
1572
1573#if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DISCARD
1574/* Discard service -- ignore data */
1575/* ARGSUSED */
1576static void
1577discard_stream(int s, servtab_t *sep)
1578{
1579 char buffer[BUFSIZE];
1580
1581 inetd_setproctitle(sep->se_service, s);
1582 while (1) {
1583 errno = 0;
1584 if (read(s, buffer, sizeof(buffer)) <= 0 && errno != EINTR)
1585 exit(0);
1586 }
1587}
1588
1589/* Discard service -- ignore data */
1590/* ARGSUSED */
1591static void
1592discard_dg(int s, servtab_t *sep ATTRIBUTE_UNUSED)
1593{
1594 char buffer[BUFSIZE];
1595
1596 (void) read(s, buffer, sizeof(buffer));
1597}
1598#endif /* FEATURE_INETD_SUPPORT_BUILTIN_DISCARD */
1599
1600
1601#if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_CHARGEN
1602#define LINESIZ 72
1603static char ring[128];
1604static char *endring;
1605
1606static void
1607initring(void)
1608{
1609 int i;
1610
1611 endring = ring;
1612
1613 for (i = 0; i <= 128; ++i)
1614 if (isprint(i))
1615 *endring++ = i;
1616}
1617
1618/* Character generator */
1619/* ARGSUSED */
1620static void
1621chargen_stream(int s, servtab_t *sep)
1622{
1623 char *rs;
1624 int len;
1625 char text[LINESIZ + 2];
1626
1627 inetd_setproctitle(sep->se_service, s);
1628
1629 if (!endring) {
1630 initring();
1631 rs = ring;
1632 }
1633
1634 text[LINESIZ] = '\r';
1635 text[LINESIZ + 1] = '\n';
1636 rs = ring;
1637 for (;;) {
1638 len = endring - rs;
1639 if (len >= LINESIZ)
1640 memmove(text, rs, LINESIZ);
1641 else {
1642 memmove(text, rs, len);
1643 memmove(text + len, ring, LINESIZ - len);
1644 }
1645 if (++rs == endring)
1646 rs = ring;
1647 if (write(s, text, sizeof(text)) != sizeof(text))
1648 break;
1649 }
1650 exit(0);
1651}
1652
1653/* Character generator */
1654/* ARGSUSED */
1655static void
1656chargen_dg(int s, servtab_t *sep ATTRIBUTE_UNUSED)
1657{
1658 /* struct sockaddr_storage ss; */
1659 struct sockaddr sa;
1660 static char *rs;
1661 int len;
1662 char text[LINESIZ + 2];
1663 socklen_t size;
1664
1665 if (endring == 0) {
1666 initring();
1667 rs = ring;
1668 }
1669
1670 size = sizeof(sa);
1671 if (recvfrom(s, text, sizeof(text), 0, &sa, &size) < 0)
1672 return;
1673 if (dg_badinput((struct sockaddr_in *) &sa))
1674 return;
1675
1676 if ((len = endring - rs) >= LINESIZ)
1677 memmove(text, rs, LINESIZ);
1678 else {
1679 memmove(text, rs, len);
1680 memmove(text + len, ring, LINESIZ - len);
1681 }
1682 if (++rs == endring)
1683 rs = ring;
1684 text[LINESIZ] = '\r';
1685 text[LINESIZ + 1] = '\n';
1686 (void) sendto(s, text, sizeof(text), 0, &sa, sizeof(sa));
1687}
1688#endif /* FEATURE_INETD_SUPPORT_BUILTIN_CHARGEN */
1689
1690
1691#if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_TIME
1692/*
1693 * Return a machine readable date and time, in the form of the
1694 * number of seconds since midnight, Jan 1, 1900. Since gettimeofday
1695 * returns the number of seconds since midnight, Jan 1, 1970,
1696 * we must add 2208988800 seconds to this figure to make up for
1697 * some seventy years Bell Labs was asleep.
1698 */
1699
1700static unsigned machtime(void)
1701{
1702 struct timeval tv;
1703
1704 if (gettimeofday(&tv, NULL) < 0) {
1705 fprintf(stderr, "Unable to get time of day\n");
1706 return 0L;
1707 }
1708 return htonl((unsigned) tv.tv_sec + 2208988800UL);
1709}
1710
1711/* ARGSUSED */
1712static void
1713machtime_stream(int s, servtab_t *sep ATTRIBUTE_UNUSED)
1714{
1715 unsigned result;
1716
1717 result = machtime();
1718 (void) write(s, (char *) &result, sizeof(result));
1719}
1720
1721/* ARGSUSED */
1722static void
1723machtime_dg(int s, servtab_t *sep ATTRIBUTE_UNUSED)
1724{
1725 unsigned result;
1726 /* struct sockaddr_storage ss; */
1727 struct sockaddr sa;
1728 struct sockaddr_in *dg_sin;
1729 socklen_t size;
1730
1731 size = sizeof(sa);
1732 if (recvfrom(s, (char *) &result, sizeof(result), 0, &sa, &size) < 0)
1733 return;
1734 /* if (dg_badinput((struct sockaddr *)&ss)) */
1735 dg_sin = (struct sockaddr_in *) &sa;
1736 if (dg_sin->sin_addr.s_addr == htonl(INADDR_BROADCAST) ||
1737 ntohs(dg_sin->sin_port) < IPPORT_RESERVED / 2)
1738 return;
1739 result = machtime();
1740 (void) sendto(s, (char *) &result, sizeof(result), 0, &sa, sizeof(sa));
1741}
1742#endif /* FEATURE_INETD_SUPPORT_BUILTIN_TIME */
1743
1744
1745#if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DAYTIME
1746/* Return human-readable time of day */
1747/* ARGSUSED */
1748static void daytime_stream(int s, servtab_t *sep ATTRIBUTE_UNUSED)
1749{
1750 char buffer[32];
1751 time_t t;
1752
1753 t = time(NULL);
1754
1755// fdprintf instead?
1756 (void) sprintf(buffer, "%.24s\r\n", ctime(&t));
1757 (void) write(s, buffer, strlen(buffer));
1758}
1759
1760/* Return human-readable time of day */
1761/* ARGSUSED */
1762void
1763daytime_dg(int s, servtab_t *sep ATTRIBUTE_UNUSED)
1764{
1765 char buffer[256];
1766 time_t t;
1767 /* struct sockaddr_storage ss; */
1768 struct sockaddr sa;
1769 socklen_t size;
1770
1771 t = time(NULL);
1772
1773 size = sizeof(sa);
1774 if (recvfrom(s, buffer, sizeof(buffer), 0, &sa, &size) < 0)
1775 return;
1776 if (dg_badinput((struct sockaddr_in *) &sa))
1777 return;
1778 (void) sprintf(buffer, "%.24s\r\n", ctime(&t));
1779 (void) sendto(s, buffer, strlen(buffer), 0, &sa, sizeof(sa));
1780}
1781#endif /* FEATURE_INETD_SUPPORT_BUILTIN_DAYTIME */
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