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 /* IPv6 support, many bug fixes by Denys Vlasenko (c) 2008 */
8 * Copyright (c) 1983,1991 The Regents of the University of California.
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 * 3. All advertising materials mentioning features or use of this software
20 * must display the following acknowledgement:
21 * This product includes software developed by the University of
22 * California, Berkeley and its contributors.
23 * 4. Neither the name of the University nor the names of its contributors
24 * may be used to endorse or promote products derived from this software
25 * without specific prior written permission.
27 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS "AS IS" AND
28 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
29 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
30 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
31 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
32 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
33 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
34 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
35 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
36 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
40 /* Inetd - Internet super-server
42 * This program invokes configured services when a connection
43 * from a peer is established or a datagram arrives.
44 * Connection-oriented services are invoked each time a
45 * connection is made, by creating a process. This process
46 * is passed the connection as file descriptor 0 and is
47 * expected to do a getpeername to find out peer's host
49 * Datagram oriented services are invoked when a datagram
50 * arrives; a process is created and passed a pending message
51 * on file descriptor 0. peer's address can be obtained
54 * Inetd uses a configuration file which is read at startup
55 * and, possibly, at some later time in response to a hangup signal.
56 * The configuration file is "free format" with fields given in the
57 * order shown below. Continuation lines for an entry must begin with
58 * a space or tab. All fields must be present in each entry.
60 * service_name must be in /etc/services
61 * socket_type stream/dgram/raw/rdm/seqpacket
62 * protocol must be in /etc/protocols
63 * (usually "tcp" or "udp")
64 * wait/nowait[.max] single-threaded/multi-threaded, max #
65 * user[.group] or user[:group] user/group to run daemon as
66 * server_program full path name
67 * server_program_arguments maximum of MAXARGS (20)
70 * service_name/version must be in /etc/rpc
71 * socket_type stream/dgram/raw/rdm/seqpacket
72 * rpc/protocol "rpc/tcp" etc
73 * wait/nowait[.max] single-threaded/multi-threaded
74 * user[.group] or user[:group] user to run daemon as
75 * server_program full path name
76 * server_program_arguments maximum of MAXARGS (20)
78 * For non-RPC services, the "service name" can be of the form
79 * hostaddress:servicename, in which case the hostaddress is used
80 * as the host portion of the address to listen on. If hostaddress
81 * consists of a single '*' character, INADDR_ANY is used.
83 * A line can also consist of just
85 * where hostaddress is as in the preceding paragraph. Such a line must
86 * have no further fields; the specified hostaddress is remembered and
87 * used for all further lines that have no hostaddress specified,
88 * until the next such line (or EOF). (This is why * is provided to
89 * allow explicit specification of INADDR_ANY.) A line
91 * is implicitly in effect at the beginning of the file.
93 * The hostaddress specifier may (and often will) contain dots;
94 * the service name must not.
96 * For RPC services, host-address specifiers are accepted and will
97 * work to some extent; however, because of limitations in the
98 * portmapper interface, it will not work to try to give more than
99 * one line for any given RPC service, even if the host-address
100 * specifiers are different.
102 * Comment lines are indicated by a '#' in column 1.
105 /* inetd rules for passing file descriptors to children
106 * (http://www.freebsd.org/cgi/man.cgi?query=inetd):
108 * The wait/nowait entry specifies whether the server that is invoked by
109 * inetd will take over the socket associated with the service access point,
110 * and thus whether inetd should wait for the server to exit before listen-
111 * ing for new service requests. Datagram servers must use "wait", as
112 * they are always invoked with the original datagram socket bound to the
113 * specified service address. These servers must read at least one datagram
114 * from the socket before exiting. If a datagram server connects to its
115 * peer, freeing the socket so inetd can receive further messages on the
116 * socket, it is said to be a "multi-threaded" server; it should read one
117 * datagram from the socket and create a new socket connected to the peer.
118 * It should fork, and the parent should then exit to allow inetd to check
119 * for new service requests to spawn new servers. Datagram servers which
120 * process all incoming datagrams on a socket and eventually time out are
121 * said to be "single-threaded". The comsat(8), biff(1) and talkd(8)
122 * utilities are both examples of the latter type of datagram server. The
123 * tftpd(8) utility is an example of a multi-threaded datagram server.
125 * Servers using stream sockets generally are multi-threaded and use the
126 * "nowait" entry. Connection requests for these services are accepted by
127 * inetd, and the server is given only the newly-accepted socket connected
128 * to a client of the service. Most stream-based services operate in this
129 * manner. Stream-based servers that use "wait" are started with the lis-
130 * tening service socket, and must accept at least one connection request
131 * before exiting. Such a server would normally accept and process incoming
132 * connection requests until a timeout.
135 /* Despite of above doc saying that dgram services must use "wait",
136 * "udp nowait" servers are implemented in busyboxed inetd.
137 * IPv6 addresses are also implemented. However, they may look ugly -
138 * ":::service..." means "address '::' (IPv6 wildcard addr)":"service"...
139 * You have to put "tcp6"/"udp6" in protocol field to select IPv6.
142 /* Here's the scoop concerning the user[:group] feature:
143 * 1) group is not specified:
144 * a) user = root: NO setuid() or setgid() is done
145 * b) other: initgroups(name, primary group)
146 * setgid(primary group as found in passwd)
148 * 2) group is specified:
149 * a) user = root: setgid(specified group)
152 * b) other: initgroups(name, specified group)
153 * setgid(specified group)
162 #if ENABLE_FEATURE_INETD_RPC
164 #include <rpc/pmap_clnt.h>
168 /* stream version of chargen is forking but not execing,
169 * can't do that (easily) on NOMMU */
170 #undef ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_CHARGEN
171 #define ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_CHARGEN 0
174 #define _PATH_INETDPID "/var/run/inetd.pid"
176 #define CNT_INTERVAL 60 /* servers in CNT_INTERVAL sec. */
177 #define RETRYTIME 60 /* retry after bind or server fail */
179 // TODO: explain, or get rid of setrlimit games
181 #ifndef RLIMIT_NOFILE
182 #define RLIMIT_NOFILE RLIMIT_OFILE
189 /* Reserve some descriptors, 3 stdio + at least: 1 log, 1 conf. file */
192 #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DISCARD \
193 || ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_ECHO \
194 || ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_CHARGEN \
195 || ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_TIME \
196 || ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DAYTIME
197 # define INETD_BUILTINS_ENABLED
200 typedef struct servtab_t
{
201 /* The most frequently referenced one: */
202 int se_fd
; /* open descriptor */
203 /* NB: 'biggest fields last' saves on code size (~250 bytes) */
204 /* [addr:]service socktype proto wait user[:group] prog [args] */
205 char *se_local_hostname
; /* addr to listen on */
206 char *se_service
; /* "80" or "www" or "mount/2[-3]" */
207 /* socktype is in se_socktype */ /* "stream" "dgram" "raw" "rdm" "seqpacket" */
208 char *se_proto
; /* "unix" or "[rpc/]tcp[6]" */
209 #if ENABLE_FEATURE_INETD_RPC
210 int se_rpcprog
; /* rpc program number */
211 int se_rpcver_lo
; /* rpc program lowest version */
212 int se_rpcver_hi
; /* rpc program highest version */
213 #define is_rpc_service(sep) ((sep)->se_rpcver_lo != 0)
215 #define is_rpc_service(sep) 0
217 pid_t se_wait
; /* 0:"nowait", 1:"wait", >1:"wait" */
218 /* and waiting for this pid */
219 socktype_t se_socktype
; /* SOCK_STREAM/DGRAM/RDM/... */
220 family_t se_family
; /* AF_UNIX/INET[6] */
221 /* se_proto_no is used by RPC code only... hmm */
222 smallint se_proto_no
; /* IPPROTO_TCP/UDP, n/a for AF_UNIX */
223 smallint se_checked
; /* looked at during merge */
224 unsigned se_max
; /* allowed instances per minute */
225 unsigned se_count
; /* number started since se_time */
226 unsigned se_time
; /* when we started counting */
227 char *se_user
; /* user name to run as */
228 char *se_group
; /* group name to run as, can be NULL */
229 #ifdef INETD_BUILTINS_ENABLED
230 const struct builtin
*se_builtin
; /* if built-in, description */
232 struct servtab_t
*se_next
;
233 len_and_sockaddr
*se_lsa
;
234 char *se_program
; /* server program */
236 char *se_argv
[MAXARGV
+ 1]; /* program arguments */
239 #ifdef INETD_BUILTINS_ENABLED
240 /* Echo received data */
241 #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_ECHO
242 static void echo_stream(int, servtab_t
*);
243 static void echo_dg(int, servtab_t
*);
245 /* Internet /dev/null */
246 #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DISCARD
247 static void discard_stream(int, servtab_t
*);
248 static void discard_dg(int, servtab_t
*);
250 /* Return 32 bit time since 1900 */
251 #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_TIME
252 static void machtime_stream(int, servtab_t
*);
253 static void machtime_dg(int, servtab_t
*);
255 /* Return human-readable time */
256 #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DAYTIME
257 static void daytime_stream(int, servtab_t
*);
258 static void daytime_dg(int, servtab_t
*);
260 /* Familiar character generator */
261 #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_CHARGEN
262 static void chargen_stream(int, servtab_t
*);
263 static void chargen_dg(int, servtab_t
*);
267 /* NB: not necessarily NUL terminated */
268 char bi_service7
[7]; /* internally provided service name */
269 uint8_t bi_fork
; /* 1 if stream fn should run in child */
270 void (*bi_stream_fn
)(int, servtab_t
*);
271 void (*bi_dgram_fn
)(int, servtab_t
*);
274 static const struct builtin builtins
[] = {
275 #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_ECHO
276 { "echo", 1, echo_stream
, echo_dg
},
278 #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DISCARD
279 { "discard", 1, discard_stream
, discard_dg
},
281 #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_CHARGEN
282 { "chargen", 1, chargen_stream
, chargen_dg
},
284 #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_TIME
285 { "time", 0, machtime_stream
, machtime_dg
},
287 #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DAYTIME
288 { "daytime", 0, daytime_stream
, daytime_dg
},
291 #endif /* INETD_BUILTINS_ENABLED */
294 rlim_t rlim_ofile_cur
;
295 struct rlimit rlim_ofile
;
296 servtab_t
*serv_list
;
298 int maxsock
; /* max fd# in allsock, -1: unknown */
299 /* whenever maxsock grows, prev_maxsock is set to new maxsock,
300 * but if maxsock is set to -1, prev_maxsock is not changed */
302 unsigned max_concurrency
;
303 smallint alarm_armed
;
304 uid_t real_uid
; /* user ID who ran us */
305 const char *config_filename
;
307 char *default_local_hostname
;
308 #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_CHARGEN
314 /* Used in next_line(), and as scratch read buffer */
315 char line
[256]; /* _at least_ 256, see LINE_SIZE */
317 #define G (*(struct globals*)&bb_common_bufsiz1)
318 enum { LINE_SIZE
= COMMON_BUFSIZE
- offsetof(struct globals
, line
) };
319 struct BUG_G_too_big
{
320 char BUG_G_too_big
[sizeof(G
) <= COMMON_BUFSIZE
? 1 : -1];
322 #define rlim_ofile_cur (G.rlim_ofile_cur )
323 #define rlim_ofile (G.rlim_ofile )
324 #define serv_list (G.serv_list )
325 #define global_queuelen (G.global_queuelen)
326 #define maxsock (G.maxsock )
327 #define prev_maxsock (G.prev_maxsock )
328 #define max_concurrency (G.max_concurrency)
329 #define alarm_armed (G.alarm_armed )
330 #define real_uid (G.real_uid )
331 #define config_filename (G.config_filename)
332 #define parser (G.parser )
333 #define default_local_hostname (G.default_local_hostname)
334 #define first_ps_byte (G.first_ps_byte )
335 #define last_ps_byte (G.last_ps_byte )
336 #define end_ring (G.end_ring )
337 #define ring_pos (G.ring_pos )
338 #define ring (G.ring )
339 #define allsock (G.allsock )
340 #define line (G.line )
341 #define INIT_G() do { \
342 rlim_ofile_cur = OPEN_MAX; \
343 global_queuelen = 128; \
344 config_filename = "/etc/inetd.conf"; \
347 static void maybe_close(int fd
)
353 // TODO: move to libbb?
354 static len_and_sockaddr
*xzalloc_lsa(int family
)
356 len_and_sockaddr
*lsa
;
359 sz
= sizeof(struct sockaddr_in
);
360 if (family
== AF_UNIX
)
361 sz
= sizeof(struct sockaddr_un
);
362 #if ENABLE_FEATURE_IPV6
363 if (family
== AF_INET6
)
364 sz
= sizeof(struct sockaddr_in6
);
366 lsa
= xzalloc(LSA_LEN_SIZE
+ sz
);
368 lsa
->u
.sa
.sa_family
= family
;
372 static void rearm_alarm(void)
380 static void block_CHLD_HUP_ALRM(sigset_t
*m
)
383 sigaddset(m
, SIGCHLD
);
384 sigaddset(m
, SIGHUP
);
385 sigaddset(m
, SIGALRM
);
386 sigprocmask(SIG_BLOCK
, m
, m
); /* old sigmask is stored in m */
389 static void restore_sigmask(sigset_t
*m
)
391 sigprocmask(SIG_SETMASK
, m
, NULL
);
394 #if ENABLE_FEATURE_INETD_RPC
395 static void register_rpc(servtab_t
*sep
)
398 struct sockaddr_in ir_sin
;
401 size
= sizeof(ir_sin
);
402 if (getsockname(sep
->se_fd
, (struct sockaddr
*) &ir_sin
, &size
) < 0) {
403 bb_perror_msg("getsockname");
407 for (n
= sep
->se_rpcver_lo
; n
<= sep
->se_rpcver_hi
; n
++) {
408 pmap_unset(sep
->se_rpcprog
, n
);
409 if (!pmap_set(sep
->se_rpcprog
, n
, sep
->se_proto_no
, ntohs(ir_sin
.sin_port
)))
410 bb_perror_msg("%s %s: pmap_set(%u,%u,%u,%u)",
411 sep
->se_service
, sep
->se_proto
,
412 sep
->se_rpcprog
, n
, sep
->se_proto_no
, ntohs(ir_sin
.sin_port
));
416 static void unregister_rpc(servtab_t
*sep
)
420 for (n
= sep
->se_rpcver_lo
; n
<= sep
->se_rpcver_hi
; n
++) {
421 if (!pmap_unset(sep
->se_rpcprog
, n
))
422 bb_perror_msg("pmap_unset(%u,%u)", sep
->se_rpcprog
, n
);
425 #endif /* FEATURE_INETD_RPC */
427 static void bump_nofile(void)
429 enum { FD_CHUNK
= 32 };
432 /* Never fails under Linux (except if you pass it bad arguments) */
433 getrlimit(RLIMIT_NOFILE
, &rl
);
434 rl
.rlim_cur
= MIN(rl
.rlim_max
, rl
.rlim_cur
+ FD_CHUNK
);
435 rl
.rlim_cur
= MIN(FD_SETSIZE
, rl
.rlim_cur
+ FD_CHUNK
);
436 if (rl
.rlim_cur
<= rlim_ofile_cur
) {
437 bb_error_msg("can't extend file limit, max = %d",
442 if (setrlimit(RLIMIT_NOFILE
, &rl
) < 0) {
443 bb_perror_msg("setrlimit");
447 rlim_ofile_cur
= rl
.rlim_cur
;
450 static void remove_fd_from_set(int fd
)
453 FD_CLR(fd
, &allsock
);
458 static void add_fd_to_set(int fd
)
461 FD_SET(fd
, &allsock
);
462 if (maxsock
>= 0 && fd
> maxsock
) {
463 prev_maxsock
= maxsock
= fd
;
464 if ((rlim_t
)fd
> rlim_ofile_cur
- FD_MARGIN
)
470 static void recalculate_maxsock(void)
474 /* We may have no services, in this case maxsock should still be >= 0
475 * (code elsewhere is not happy with maxsock == -1) */
477 while (fd
<= prev_maxsock
) {
478 if (FD_ISSET(fd
, &allsock
))
482 prev_maxsock
= maxsock
;
483 if ((rlim_t
)maxsock
> rlim_ofile_cur
- FD_MARGIN
)
487 static void prepare_socket_fd(servtab_t
*sep
)
491 fd
= socket(sep
->se_family
, sep
->se_socktype
, 0);
493 bb_perror_msg("socket");
496 setsockopt_reuseaddr(fd
);
498 #if ENABLE_FEATURE_INETD_RPC
499 if (is_rpc_service(sep
)) {
502 /* zero out the port for all RPC services; let bind()
504 set_nport(sep
->se_lsa
, 0);
506 /* for RPC services, attempt to use a reserved port
507 * if they are going to be running as root. */
508 if (real_uid
== 0 && sep
->se_family
== AF_INET
509 && (pwd
= getpwnam(sep
->se_user
)) != NULL
512 r
= bindresvport(fd
, &sep
->se_lsa
->u
.sin
);
514 r
= bind(fd
, &sep
->se_lsa
->u
.sa
, sep
->se_lsa
->len
);
517 int saveerrno
= errno
;
518 /* update lsa with port# */
519 getsockname(fd
, &sep
->se_lsa
->u
.sa
, &sep
->se_lsa
->len
);
525 if (sep
->se_family
== AF_UNIX
) {
526 struct sockaddr_un
*sun
;
527 sun
= (struct sockaddr_un
*)&(sep
->se_lsa
->u
.sa
);
528 unlink(sun
->sun_path
);
530 r
= bind(fd
, &sep
->se_lsa
->u
.sa
, sep
->se_lsa
->len
);
533 bb_perror_msg("%s/%s: bind",
534 sep
->se_service
, sep
->se_proto
);
539 if (sep
->se_socktype
== SOCK_STREAM
)
540 listen(fd
, global_queuelen
);
546 static int reopen_config_file(void)
548 free(default_local_hostname
);
549 default_local_hostname
= xstrdup("*");
551 config_close(parser
);
552 parser
= config_open(config_filename
);
553 return (parser
!= NULL
);
556 static void close_config_file(void)
559 config_close(parser
);
564 static void free_servtab_strings(servtab_t
*cp
)
568 free(cp
->se_local_hostname
);
569 free(cp
->se_service
);
573 free(cp
->se_lsa
); /* not a string in fact */
574 free(cp
->se_program
);
575 for (i
= 0; i
< MAXARGV
; i
++)
576 free(cp
->se_argv
[i
]);
579 static servtab_t
*new_servtab(void)
581 servtab_t
*newtab
= xzalloc(sizeof(servtab_t
));
582 newtab
->se_fd
= -1; /* paranoia */
586 static servtab_t
*dup_servtab(servtab_t
*sep
)
591 newtab
= new_servtab();
592 *newtab
= *sep
; /* struct copy */
593 /* deep-copying strings */
594 newtab
->se_service
= xstrdup(newtab
->se_service
);
595 newtab
->se_proto
= xstrdup(newtab
->se_proto
);
596 newtab
->se_user
= xstrdup(newtab
->se_user
);
597 newtab
->se_group
= xstrdup(newtab
->se_group
);
598 newtab
->se_program
= xstrdup(newtab
->se_program
);
599 for (argc
= 0; argc
<= MAXARGV
; argc
++)
600 newtab
->se_argv
[argc
] = xstrdup(newtab
->se_argv
[argc
]);
601 /* NB: se_fd, se_hostaddr and se_next are always
602 * overwrittend by callers, so we don't bother resetting them
603 * to NULL/0/-1 etc */
608 /* gcc generates much more code if this is inlined */
609 static servtab_t
*parse_one_line(void)
612 char *token
[6+MAXARGV
];
620 argc
= config_read(parser
, token
, 6+MAXARGV
, 1, "# \t", PARSE_NORMAL
);
626 /* [host:]service socktype proto wait user[:group] prog [args] */
627 /* Check for "host:...." line */
629 hostdelim
= strrchr(arg
, ':');
632 sep
->se_local_hostname
= xstrdup(arg
);
634 if (*arg
== '\0' && argc
== 1) {
635 /* Line has just "host:", change the
636 * default host for the following lines. */
637 free(default_local_hostname
);
638 default_local_hostname
= sep
->se_local_hostname
;
642 sep
->se_local_hostname
= xstrdup(default_local_hostname
);
644 /* service socktype proto wait user[:group] prog [args] */
645 sep
->se_service
= xstrdup(arg
);
647 /* socktype proto wait user[:group] prog [args] */
650 bb_error_msg("parse error on line %u, line is ignored",
652 free_servtab_strings(sep
);
653 /* Just "goto more" can make sep to carry over e.g.
654 * "rpc"-ness (by having se_rpcver_lo != 0).
655 * We will be more paranoid: */
661 static int8_t SOCK_xxx
[] ALIGN1
= {
663 SOCK_STREAM
, SOCK_DGRAM
, SOCK_RDM
,
664 SOCK_SEQPACKET
, SOCK_RAW
666 sep
->se_socktype
= SOCK_xxx
[1 + index_in_strings(
667 "stream""\0" "dgram""\0" "rdm""\0"
668 "seqpacket""\0" "raw""\0"
672 /* {unix,[rpc/]{tcp,udp}[6]} wait user[:group] prog [args] */
673 sep
->se_proto
= arg
= xstrdup(token
[2]);
674 if (strcmp(arg
, "unix") == 0) {
675 sep
->se_family
= AF_UNIX
;
678 sep
->se_family
= AF_INET
;
679 six
= last_char_is(arg
, '6');
681 #if ENABLE_FEATURE_IPV6
683 sep
->se_family
= AF_INET6
;
685 bb_error_msg("%s: no support for IPv6", sep
->se_proto
);
689 if (strncmp(arg
, "rpc/", 4) == 0) {
690 #if ENABLE_FEATURE_INETD_RPC
693 p
= strchr(sep
->se_service
, '/');
695 bb_error_msg("no rpc version: '%s'", sep
->se_service
);
699 n
= bb_strtou(p
, &p
, 10);
702 bb_error_msg("bad rpc version");
705 sep
->se_rpcver_lo
= sep
->se_rpcver_hi
= n
;
708 n
= bb_strtou(p
, &p
, 10);
709 if (n
> INT_MAX
|| (int)n
< sep
->se_rpcver_lo
)
711 sep
->se_rpcver_hi
= n
;
716 bb_error_msg("no support for rpc services");
720 /* we don't really need getprotobyname()! */
721 if (strcmp(arg
, "tcp") == 0)
722 sep
->se_proto_no
= IPPROTO_TCP
; /* = 6 */
723 if (strcmp(arg
, "udp") == 0)
724 sep
->se_proto_no
= IPPROTO_UDP
; /* = 17 */
727 if (!sep
->se_proto_no
) /* not tcp/udp?? */
731 /* [no]wait[.max] user[:group] prog [args] */
733 sep
->se_max
= max_concurrency
;
734 p
= strchr(arg
, '.');
737 sep
->se_max
= bb_strtou(p
, NULL
, 10);
741 sep
->se_wait
= (arg
[0] != 'n' || arg
[1] != 'o');
742 if (!sep
->se_wait
) /* "no" seen */
744 if (strcmp(arg
, "wait") != 0)
747 /* user[:group] prog [args] */
748 sep
->se_user
= xstrdup(token
[4]);
749 arg
= strchr(sep
->se_user
, '.');
751 arg
= strchr(sep
->se_user
, ':');
754 sep
->se_group
= xstrdup(arg
);
758 sep
->se_program
= xstrdup(token
[5]);
759 #ifdef INETD_BUILTINS_ENABLED
760 if (strcmp(sep
->se_program
, "internal") == 0
761 && strlen(sep
->se_service
) <= 7
762 && (sep
->se_socktype
== SOCK_STREAM
763 || sep
->se_socktype
== SOCK_DGRAM
)
766 for (i
= 0; i
< ARRAY_SIZE(builtins
); i
++)
767 if (strncmp(builtins
[i
].bi_service7
, sep
->se_service
, 7) == 0)
769 bb_error_msg("unknown internal service %s", sep
->se_service
);
772 sep
->se_builtin
= &builtins
[i
];
773 /* stream builtins must be "nowait", dgram must be "wait" */
774 if (sep
->se_wait
!= (sep
->se_socktype
== SOCK_DGRAM
))
779 while ((arg
= token
[6+argc
]) != NULL
&& argc
< MAXARGV
)
780 sep
->se_argv
[argc
++] = xstrdup(arg
);
782 /* catch mixups. "<service> stream udp ..." == wtf */
783 if (sep
->se_socktype
== SOCK_STREAM
) {
784 if (sep
->se_proto_no
== IPPROTO_UDP
)
787 if (sep
->se_socktype
== SOCK_DGRAM
) {
788 if (sep
->se_proto_no
== IPPROTO_TCP
)
793 // "ENTRY[%s][%s][%s][%d][%d][%d][%d][%d][%s][%s][%s]",
794 // sep->se_local_hostname, sep->se_service, sep->se_proto, sep->se_wait, sep->se_proto_no,
795 // sep->se_max, sep->se_count, sep->se_time, sep->se_user, sep->se_group, sep->se_program);
797 /* check if the hostname specifier is a comma separated list
798 * of hostnames. we'll make new entries for each address. */
799 while ((hostdelim
= strrchr(sep
->se_local_hostname
, ',')) != NULL
) {
800 nsep
= dup_servtab(sep
);
801 /* NUL terminate the hostname field of the existing entry,
802 * and make a dup for the new entry. */
804 nsep
->se_local_hostname
= xstrdup(hostdelim
);
805 nsep
->se_next
= sep
->se_next
;
809 /* was doing it here: */
810 /* DNS resolution, create copies for each IP address */
811 /* IPv6-ization destroyed it :( */
816 static servtab_t
*insert_in_servlist(servtab_t
*cp
)
822 *sep
= *cp
; /* struct copy */
824 #if ENABLE_FEATURE_INETD_RPC
825 sep
->se_rpcprog
= -1;
827 block_CHLD_HUP_ALRM(&omask
);
828 sep
->se_next
= serv_list
;
830 restore_sigmask(&omask
);
834 static int same_serv_addr_proto(servtab_t
*old
, servtab_t
*new)
836 if (strcmp(old
->se_local_hostname
, new->se_local_hostname
) != 0)
838 if (strcmp(old
->se_service
, new->se_service
) != 0)
840 if (strcmp(old
->se_proto
, new->se_proto
) != 0)
845 static void reread_config_file(int sig UNUSED_PARAM
)
847 servtab_t
*sep
, *cp
, **sepp
;
848 len_and_sockaddr
*lsa
;
852 int save_errno
= errno
;
854 if (!reopen_config_file())
856 for (sep
= serv_list
; sep
; sep
= sep
->se_next
)
863 cp
= parse_one_line();
867 for (sep
= serv_list
; sep
; sep
= sep
->se_next
)
868 if (same_serv_addr_proto(sep
, cp
))
870 /* not an "equal" servtab */
871 sep
= insert_in_servlist(cp
);
877 block_CHLD_HUP_ALRM(&omask
);
878 #if ENABLE_FEATURE_INETD_RPC
879 if (is_rpc_service(sep
))
881 sep
->se_rpcver_lo
= cp
->se_rpcver_lo
;
882 sep
->se_rpcver_hi
= cp
->se_rpcver_hi
;
884 if (cp
->se_wait
== 0) {
885 /* New config says "nowait". If old one
886 * was "wait", we currently may be waiting
887 * for a child (and not accepting connects).
888 * Stop waiting, start listening again.
889 * (if it's not true, this op is harmless) */
890 add_fd_to_set(sep
->se_fd
);
892 sep
->se_wait
= cp
->se_wait
;
893 sep
->se_max
= cp
->se_max
;
894 /* string fields need more love - we don't want to leak them */
895 #define SWAP(type, a, b) do { type c = (type)a; a = (type)b; b = (type)c; } while (0)
896 SWAP(char*, sep
->se_user
, cp
->se_user
);
897 SWAP(char*, sep
->se_group
, cp
->se_group
);
898 SWAP(char*, sep
->se_program
, cp
->se_program
);
899 for (i
= 0; i
< MAXARGV
; i
++)
900 SWAP(char*, sep
->se_argv
[i
], cp
->se_argv
[i
]);
902 restore_sigmask(&omask
);
903 free_servtab_strings(cp
);
906 /* cp->string_fields are consumed by insert_in_servlist()
907 * or freed at this point, cp itself is not yet freed. */
910 /* create new len_and_sockaddr */
911 switch (sep
->se_family
) {
912 struct sockaddr_un
*sun
;
914 lsa
= xzalloc_lsa(AF_UNIX
);
915 sun
= (struct sockaddr_un
*)&lsa
->u
.sa
;
916 safe_strncpy(sun
->sun_path
, sep
->se_service
, sizeof(sun
->sun_path
));
919 default: /* case AF_INET, case AF_INET6 */
920 n
= bb_strtou(sep
->se_service
, NULL
, 10);
921 #if ENABLE_FEATURE_INETD_RPC
922 if (is_rpc_service(sep
)) {
924 if (errno
) { /* se_service is not numeric */
925 struct rpcent
*rp
= getrpcbyname(sep
->se_service
);
927 bb_error_msg("%s: unknown rpc service", sep
->se_service
);
930 sep
->se_rpcprog
= rp
->r_number
;
932 if (sep
->se_fd
== -1)
933 prepare_socket_fd(sep
);
934 if (sep
->se_fd
!= -1)
939 /* what port to listen on? */
941 if (errno
|| n
> 0xffff) { /* se_service is not numeric */
944 /* can result only in "tcp" or "udp": */
945 safe_strncpy(protoname
, sep
->se_proto
, 4);
946 sp
= getservbyname(sep
->se_service
, protoname
);
948 bb_error_msg("%s/%s: unknown service",
949 sep
->se_service
, sep
->se_proto
);
954 if (LONE_CHAR(sep
->se_local_hostname
, '*')) {
955 lsa
= xzalloc_lsa(sep
->se_family
);
956 set_nport(lsa
, port
);
958 lsa
= host_and_af2sockaddr(sep
->se_local_hostname
,
959 ntohs(port
), sep
->se_family
);
961 bb_error_msg("%s/%s: unknown host '%s'",
962 sep
->se_service
, sep
->se_proto
,
963 sep
->se_local_hostname
);
968 } /* end of "switch (sep->se_family)" */
970 /* did lsa change? Then close/open */
971 if (sep
->se_lsa
== NULL
972 || lsa
->len
!= sep
->se_lsa
->len
973 || memcmp(&lsa
->u
.sa
, &sep
->se_lsa
->u
.sa
, lsa
->len
) != 0
975 remove_fd_from_set(sep
->se_fd
);
976 maybe_close(sep
->se_fd
);
983 if (sep
->se_fd
== -1)
984 prepare_socket_fd(sep
);
989 } /* end of "while (1) parse lines" */
992 /* Purge anything not looked at above - these are stale entries,
993 * new config file doesnt have them. */
994 block_CHLD_HUP_ALRM(&omask
);
996 while ((sep
= *sepp
)) {
997 if (sep
->se_checked
) {
998 sepp
= &sep
->se_next
;
1001 *sepp
= sep
->se_next
;
1002 remove_fd_from_set(sep
->se_fd
);
1003 maybe_close(sep
->se_fd
);
1004 #if ENABLE_FEATURE_INETD_RPC
1005 if (is_rpc_service(sep
))
1006 unregister_rpc(sep
);
1008 if (sep
->se_family
== AF_UNIX
)
1009 unlink(sep
->se_service
);
1010 free_servtab_strings(sep
);
1013 restore_sigmask(&omask
);
1018 static void reap_child(int sig UNUSED_PARAM
)
1023 int save_errno
= errno
;
1026 pid
= wait_any_nohang(&status
);
1029 for (sep
= serv_list
; sep
; sep
= sep
->se_next
) {
1030 if (sep
->se_wait
!= pid
)
1032 /* One of our "wait" services */
1033 if (WIFEXITED(status
) && WEXITSTATUS(status
))
1034 bb_error_msg("%s: exit status 0x%x",
1035 sep
->se_program
, WEXITSTATUS(status
));
1036 else if (WIFSIGNALED(status
))
1037 bb_error_msg("%s: exit signal 0x%x",
1038 sep
->se_program
, WTERMSIG(status
));
1040 add_fd_to_set(sep
->se_fd
);
1047 static void retry_network_setup(int sig UNUSED_PARAM
)
1049 int save_errno
= errno
;
1053 for (sep
= serv_list
; sep
; sep
= sep
->se_next
) {
1054 if (sep
->se_fd
== -1) {
1055 prepare_socket_fd(sep
);
1056 #if ENABLE_FEATURE_INETD_RPC
1057 if (sep
->se_fd
!= -1 && is_rpc_service(sep
))
1065 static void clean_up_and_exit(int sig UNUSED_PARAM
)
1069 /* XXX signal race walking sep list */
1070 for (sep
= serv_list
; sep
; sep
= sep
->se_next
) {
1071 if (sep
->se_fd
== -1)
1074 switch (sep
->se_family
) {
1076 unlink(sep
->se_service
);
1078 default: /* case AF_INET, AF_INET6 */
1079 #if ENABLE_FEATURE_INETD_RPC
1080 if (sep
->se_wait
== 1 && is_rpc_service(sep
))
1081 unregister_rpc(sep
); /* XXX signal race */
1085 if (ENABLE_FEATURE_CLEAN_UP
)
1088 remove_pidfile(_PATH_INETDPID
);
1092 int inetd_main(int argc
, char **argv
) MAIN_EXTERNALLY_VISIBLE
;
1093 int inetd_main(int argc UNUSED_PARAM
, char **argv
)
1095 struct sigaction sa
, saved_pipe_handler
;
1096 servtab_t
*sep
, *sep2
;
1098 struct group
*grp
= grp
; /* for compiler */
1105 real_uid
= getuid();
1106 if (real_uid
!= 0) /* run by non-root user */
1107 config_filename
= NULL
;
1109 opt_complementary
= "R+:q+"; /* -q N, -R N */
1110 opt
= getopt32(argv
, "R:feq:", &max_concurrency
, &global_queuelen
);
1114 config_filename
= argv
[0];
1115 if (config_filename
== NULL
)
1116 bb_error_msg_and_die("non-root must specify config file");
1118 bb_daemonize_or_rexec(0, argv
- optind
);
1120 bb_sanitize_stdio();
1122 openlog(applet_name
, LOG_PID
, LOG_DAEMON
);
1123 logmode
= LOGMODE_SYSLOG
;
1126 if (real_uid
== 0) {
1127 /* run by root, ensure groups vector gets trashed */
1128 gid_t gid
= getgid();
1132 write_pidfile(_PATH_INETDPID
);
1134 /* never fails under Linux (except if you pass it bad arguments) */
1135 getrlimit(RLIMIT_NOFILE
, &rlim_ofile
);
1136 rlim_ofile_cur
= rlim_ofile
.rlim_cur
;
1137 if (rlim_ofile_cur
== RLIM_INFINITY
) /* ! */
1138 rlim_ofile_cur
= OPEN_MAX
;
1140 memset(&sa
, 0, sizeof(sa
));
1141 /*sigemptyset(&sa.sa_mask); - memset did it */
1142 sigaddset(&sa
.sa_mask
, SIGALRM
);
1143 sigaddset(&sa
.sa_mask
, SIGCHLD
);
1144 sigaddset(&sa
.sa_mask
, SIGHUP
);
1145 sa
.sa_handler
= retry_network_setup
;
1146 sigaction_set(SIGALRM
, &sa
);
1147 sa
.sa_handler
= reread_config_file
;
1148 sigaction_set(SIGHUP
, &sa
);
1149 sa
.sa_handler
= reap_child
;
1150 sigaction_set(SIGCHLD
, &sa
);
1151 sa
.sa_handler
= clean_up_and_exit
;
1152 sigaction_set(SIGTERM
, &sa
);
1153 sa
.sa_handler
= clean_up_and_exit
;
1154 sigaction_set(SIGINT
, &sa
);
1155 sa
.sa_handler
= SIG_IGN
;
1156 sigaction(SIGPIPE
, &sa
, &saved_pipe_handler
);
1158 reread_config_file(SIGHUP
); /* load config from file */
1162 int ctrl
, accepted_fd
, new_udp_fd
;
1166 recalculate_maxsock();
1168 readable
= allsock
; /* struct copy */
1169 /* if there are no fds to wait on, we will block
1170 * until signal wakes us up (maxsock == 0, but readable
1171 * never contains fds 0 and 1...) */
1172 ready_fd_cnt
= select(maxsock
+ 1, &readable
, NULL
, NULL
, NULL
);
1173 if (ready_fd_cnt
< 0) {
1174 if (errno
!= EINTR
) {
1175 bb_perror_msg("select");
1181 for (sep
= serv_list
; ready_fd_cnt
&& sep
; sep
= sep
->se_next
) {
1182 if (sep
->se_fd
== -1 || !FD_ISSET(sep
->se_fd
, &readable
))
1189 if (!sep
->se_wait
) {
1190 if (sep
->se_socktype
== SOCK_STREAM
) {
1191 ctrl
= accepted_fd
= accept(sep
->se_fd
, NULL
, NULL
);
1194 bb_perror_msg("accept (for %s)", sep
->se_service
);
1199 if (sep
->se_socktype
== SOCK_DGRAM
1200 && sep
->se_family
!= AF_UNIX
1202 /* How udp "nowait" works:
1203 * child peeks at (received and buffered by kernel) UDP packet,
1204 * performs connect() on the socket so that it is linked only
1205 * to this peer. But this also affects parent, because descriptors
1206 * are shared after fork() a-la dup(). When parent performs
1207 * select(), it will see this descriptor connected to the peer (!)
1208 * and still readable, will act on it and mess things up
1209 * (can create many copies of same child, etc).
1210 * Parent must create and use new socket instead. */
1211 new_udp_fd
= socket(sep
->se_family
, SOCK_DGRAM
, 0);
1212 if (new_udp_fd
< 0) { /* error: eat packet, forget about it */
1214 recv(sep
->se_fd
, line
, LINE_SIZE
, MSG_DONTWAIT
);
1217 setsockopt_reuseaddr(new_udp_fd
);
1218 /* TODO: better do bind after vfork in parent,
1219 * so that we don't have two wildcard bound sockets
1220 * even for a brief moment? */
1221 if (bind(new_udp_fd
, &sep
->se_lsa
->u
.sa
, sep
->se_lsa
->len
) < 0) {
1228 block_CHLD_HUP_ALRM(&omask
);
1230 #ifdef INETD_BUILTINS_ENABLED
1231 /* do we need to fork? */
1232 if (sep
->se_builtin
== NULL
1233 || (sep
->se_socktype
== SOCK_STREAM
1234 && sep
->se_builtin
->bi_fork
))
1237 if (sep
->se_max
!= 0) {
1238 if (++sep
->se_count
== 1)
1239 sep
->se_time
= monotonic_sec();
1240 else if (sep
->se_count
>= sep
->se_max
) {
1241 unsigned now
= monotonic_sec();
1242 /* did we accumulate se_max connects too quickly? */
1243 if (now
- sep
->se_time
<= CNT_INTERVAL
) {
1244 bb_error_msg("%s/%s: too many connections, pausing",
1245 sep
->se_service
, sep
->se_proto
);
1246 remove_fd_from_set(sep
->se_fd
);
1250 rearm_alarm(); /* will revive it in RETRYTIME sec */
1251 restore_sigmask(&omask
);
1252 maybe_close(accepted_fd
);
1253 continue; /* -> check next fd in fd set */
1258 /* on NOMMU, streamed chargen
1259 * builtin wouldn't work, but it is
1260 * not allowed on NOMMU (ifdefed out) */
1261 #ifdef INETD_BUILTINS_ENABLED
1262 if (BB_MMU
&& sep
->se_builtin
)
1268 if (pid
< 0) { /* fork error */
1269 bb_perror_msg("fork");
1271 restore_sigmask(&omask
);
1272 maybe_close(accepted_fd
);
1273 continue; /* -> check next fd in fd set */
1276 pid
--; /* -1: "we did fork and we are child" */
1278 /* if pid == 0 here, we never forked */
1280 if (pid
> 0) { /* parent */
1282 /* tcp wait: we passed listening socket to child,
1283 * will wait for child to terminate */
1285 remove_fd_from_set(sep
->se_fd
);
1287 if (new_udp_fd
>= 0) {
1288 /* udp nowait: child connected the socket,
1289 * we created and will use new, unconnected one */
1290 xmove_fd(new_udp_fd
, sep
->se_fd
);
1292 restore_sigmask(&omask
);
1293 maybe_close(accepted_fd
);
1294 continue; /* -> check next fd in fd set */
1297 /* we are either child or didn't vfork at all */
1298 #ifdef INETD_BUILTINS_ENABLED
1299 if (sep
->se_builtin
) {
1300 if (pid
) { /* "pid" is -1: we did vfork */
1301 close(sep
->se_fd
); /* listening socket */
1302 logmode
= LOGMODE_NONE
; /* make xwrite etc silent */
1304 restore_sigmask(&omask
);
1305 if (sep
->se_socktype
== SOCK_STREAM
)
1306 sep
->se_builtin
->bi_stream_fn(ctrl
, sep
);
1308 sep
->se_builtin
->bi_dgram_fn(ctrl
, sep
);
1309 if (pid
) /* we did vfork */
1310 _exit(EXIT_FAILURE
);
1311 maybe_close(accepted_fd
);
1312 continue; /* -> check next fd in fd set */
1318 if (new_udp_fd
>= 0) {
1319 len_and_sockaddr
*lsa
= xzalloc_lsa(sep
->se_family
);
1320 /* peek at the packet and remember peer addr */
1321 int r
= recvfrom(ctrl
, NULL
, 0, MSG_PEEK
|MSG_DONTWAIT
,
1322 &lsa
->u
.sa
, &lsa
->len
);
1325 /* make this socket "connected" to peer addr:
1326 * only packets from this peer will be recv'ed,
1327 * and bare write()/send() will work on it */
1328 connect(ctrl
, &lsa
->u
.sa
, lsa
->len
);
1331 /* prepare env and exec program */
1332 pwd
= getpwnam(sep
->se_user
);
1334 bb_error_msg("%s: no such %s", sep
->se_user
, "user");
1337 if (sep
->se_group
&& (grp
= getgrnam(sep
->se_group
)) == NULL
) {
1338 bb_error_msg("%s: no such %s", sep
->se_group
, "group");
1341 if (real_uid
!= 0 && real_uid
!= pwd
->pw_uid
) {
1342 /* a user running private inetd */
1343 bb_error_msg("non-root must run services as himself");
1348 pwd
->pw_gid
= grp
->gr_gid
;
1349 /* initgroups, setgid, setuid: */
1350 change_identity(pwd
);
1351 } else if (sep
->se_group
) {
1352 xsetgid(grp
->gr_gid
);
1353 setgroups(1, &grp
->gr_gid
);
1355 if (rlim_ofile
.rlim_cur
!= rlim_ofile_cur
)
1356 if (setrlimit(RLIMIT_NOFILE
, &rlim_ofile
) < 0)
1357 bb_perror_msg("setrlimit");
1362 /* NB: among others, this loop closes listening socket
1363 * for nowait stream children */
1364 for (sep2
= serv_list
; sep2
; sep2
= sep2
->se_next
)
1365 maybe_close(sep2
->se_fd
);
1366 sigaction_set(SIGPIPE
, &saved_pipe_handler
);
1367 restore_sigmask(&omask
);
1368 BB_EXECVP(sep
->se_program
, sep
->se_argv
);
1369 bb_perror_msg("exec %s", sep
->se_program
);
1371 /* eat packet in udp case */
1372 if (sep
->se_socktype
!= SOCK_STREAM
)
1373 recv(0, line
, LINE_SIZE
, MSG_DONTWAIT
);
1374 _exit(EXIT_FAILURE
);
1375 } /* for (sep = servtab...) */
1380 static const char *const cat_args
[] = { "cat", NULL
};
1384 * Internet services provided internally by inetd:
1386 #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_ECHO
1387 /* Echo service -- echo data back. */
1389 static void echo_stream(int s
, servtab_t
*sep UNUSED_PARAM
)
1393 ssize_t sz
= safe_read(s
, line
, LINE_SIZE
);
1396 xwrite(s
, line
, sz
);
1399 /* We are after vfork here! */
1400 /* move network socket to stdin/stdout */
1401 xmove_fd(s
, STDIN_FILENO
);
1402 xdup2(STDIN_FILENO
, STDOUT_FILENO
);
1403 /* no error messages please... */
1404 close(STDERR_FILENO
);
1405 xopen(bb_dev_null
, O_WRONLY
);
1406 BB_EXECVP("cat", (char**)cat_args
);
1407 /* on failure we return to main, which does exit(EXIT_FAILURE) */
1410 static void echo_dg(int s
, servtab_t
*sep
)
1412 enum { BUFSIZE
= 12*1024 }; /* for jumbo sized packets! :) */
1413 char *buf
= xmalloc(BUFSIZE
); /* too big for stack */
1415 len_and_sockaddr
*lsa
= alloca(LSA_LEN_SIZE
+ sep
->se_lsa
->len
);
1417 lsa
->len
= sep
->se_lsa
->len
;
1418 /* dgram builtins are non-forking - DONT BLOCK! */
1419 sz
= recvfrom(s
, buf
, BUFSIZE
, MSG_DONTWAIT
, &lsa
->u
.sa
, &lsa
->len
);
1421 sendto(s
, buf
, sz
, 0, &lsa
->u
.sa
, lsa
->len
);
1424 #endif /* FEATURE_INETD_SUPPORT_BUILTIN_ECHO */
1427 #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DISCARD
1428 /* Discard service -- ignore data. */
1430 static void discard_stream(int s
, servtab_t
*sep UNUSED_PARAM
)
1433 while (safe_read(s
, line
, LINE_SIZE
) > 0)
1436 /* We are after vfork here! */
1437 /* move network socket to stdin */
1438 xmove_fd(s
, STDIN_FILENO
);
1439 /* discard output */
1440 close(STDOUT_FILENO
);
1441 xopen(bb_dev_null
, O_WRONLY
);
1442 /* no error messages please... */
1443 xdup2(STDOUT_FILENO
, STDERR_FILENO
);
1444 BB_EXECVP("cat", (char**)cat_args
);
1445 /* on failure we return to main, which does exit(EXIT_FAILURE) */
1449 static void discard_dg(int s
, servtab_t
*sep UNUSED_PARAM
)
1451 /* dgram builtins are non-forking - DONT BLOCK! */
1452 recv(s
, line
, LINE_SIZE
, MSG_DONTWAIT
);
1454 #endif /* FEATURE_INETD_SUPPORT_BUILTIN_DISCARD */
1457 #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_CHARGEN
1459 static void init_ring(void)
1464 for (i
= 0; i
<= 128; ++i
)
1468 /* Character generator. MMU arches only. */
1470 static void chargen_stream(int s
, servtab_t
*sep UNUSED_PARAM
)
1474 char text
[LINESIZ
+ 2];
1481 text
[LINESIZ
] = '\r';
1482 text
[LINESIZ
+ 1] = '\n';
1485 len
= end_ring
- rs
;
1487 memmove(text
, rs
, LINESIZ
);
1489 memmove(text
, rs
, len
);
1490 memmove(text
+ len
, ring
, LINESIZ
- len
);
1492 if (++rs
== end_ring
)
1494 xwrite(s
, text
, sizeof(text
));
1498 static void chargen_dg(int s
, servtab_t
*sep
)
1501 char text
[LINESIZ
+ 2];
1502 len_and_sockaddr
*lsa
= alloca(LSA_LEN_SIZE
+ sep
->se_lsa
->len
);
1504 /* Eat UDP packet which started it all */
1505 /* dgram builtins are non-forking - DONT BLOCK! */
1506 lsa
->len
= sep
->se_lsa
->len
;
1507 if (recvfrom(s
, text
, sizeof(text
), MSG_DONTWAIT
, &lsa
->u
.sa
, &lsa
->len
) < 0)
1515 len
= end_ring
- ring_pos
;
1517 memmove(text
, ring_pos
, LINESIZ
);
1519 memmove(text
, ring_pos
, len
);
1520 memmove(text
+ len
, ring
, LINESIZ
- len
);
1522 if (++ring_pos
== end_ring
)
1524 text
[LINESIZ
] = '\r';
1525 text
[LINESIZ
+ 1] = '\n';
1526 sendto(s
, text
, sizeof(text
), 0, &lsa
->u
.sa
, lsa
->len
);
1528 #endif /* FEATURE_INETD_SUPPORT_BUILTIN_CHARGEN */
1531 #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_TIME
1533 * Return a machine readable date and time, in the form of the
1534 * number of seconds since midnight, Jan 1, 1900. Since gettimeofday
1535 * returns the number of seconds since midnight, Jan 1, 1970,
1536 * we must add 2208988800 seconds to this figure to make up for
1537 * some seventy years Bell Labs was asleep.
1539 static uint32_t machtime(void)
1543 gettimeofday(&tv
, NULL
);
1544 return htonl((uint32_t)(tv
.tv_sec
+ 2208988800));
1547 static void machtime_stream(int s
, servtab_t
*sep UNUSED_PARAM
)
1551 result
= machtime();
1552 full_write(s
, &result
, sizeof(result
));
1554 static void machtime_dg(int s
, servtab_t
*sep
)
1557 len_and_sockaddr
*lsa
= alloca(LSA_LEN_SIZE
+ sep
->se_lsa
->len
);
1559 lsa
->len
= sep
->se_lsa
->len
;
1560 if (recvfrom(s
, line
, LINE_SIZE
, MSG_DONTWAIT
, &lsa
->u
.sa
, &lsa
->len
) < 0)
1563 result
= machtime();
1564 sendto(s
, &result
, sizeof(result
), 0, &lsa
->u
.sa
, lsa
->len
);
1566 #endif /* FEATURE_INETD_SUPPORT_BUILTIN_TIME */
1569 #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DAYTIME
1570 /* Return human-readable time of day */
1572 static void daytime_stream(int s
, servtab_t
*sep UNUSED_PARAM
)
1577 fdprintf(s
, "%.24s\r\n", ctime(&t
));
1579 static void daytime_dg(int s
, servtab_t
*sep
)
1582 len_and_sockaddr
*lsa
= alloca(LSA_LEN_SIZE
+ sep
->se_lsa
->len
);
1584 lsa
->len
= sep
->se_lsa
->len
;
1585 if (recvfrom(s
, line
, LINE_SIZE
, MSG_DONTWAIT
, &lsa
->u
.sa
, &lsa
->len
) < 0)
1589 sprintf(line
, "%.24s\r\n", ctime(&t
));
1590 sendto(s
, line
, strlen(line
), 0, &lsa
->u
.sa
, lsa
->len
);
1592 #endif /* FEATURE_INETD_SUPPORT_BUILTIN_DAYTIME */