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 */
|
---|
7 | /*
|
---|
8 | * Copyright (c) 1983,1991 The Regents of the University of California.
|
---|
9 | * All rights reserved.
|
---|
10 | *
|
---|
11 | * Redistribution and use in source and binary forms, with or without
|
---|
12 | * modification, are permitted provided that the following conditions
|
---|
13 | * are met:
|
---|
14 | * 1. Redistributions of source code must retain the above copyright
|
---|
15 | * notice, this list of conditions and the following disclaimer.
|
---|
16 | * 2. Redistributions in binary form must reproduce the above copyright
|
---|
17 | * notice, this list of conditions and the following disclaimer in the
|
---|
18 | * documentation and/or other materials provided with the distribution.
|
---|
19 | * 3. All advertising materials mentioning features or use of this software
|
---|
20 | * must display the following acknowledgement:
|
---|
21 | * This product includes software developed by the 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.
|
---|
26 | *
|
---|
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
|
---|
37 | * SUCH DAMAGE.
|
---|
38 | */
|
---|
39 |
|
---|
40 | /* Inetd - Internet super-server
|
---|
41 | *
|
---|
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
|
---|
48 | * and port.
|
---|
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
|
---|
52 | * using recvfrom.
|
---|
53 | *
|
---|
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.
|
---|
59 | *
|
---|
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)
|
---|
68 | *
|
---|
69 | * For RPC services
|
---|
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)
|
---|
77 | *
|
---|
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.
|
---|
82 | *
|
---|
83 | * A line can also consist of just
|
---|
84 | * hostaddress:
|
---|
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
|
---|
90 | * *:
|
---|
91 | * is implicitly in effect at the beginning of the file.
|
---|
92 | *
|
---|
93 | * The hostaddress specifier may (and often will) contain dots;
|
---|
94 | * the service name must not.
|
---|
95 | *
|
---|
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.
|
---|
101 | *
|
---|
102 | * Comment lines are indicated by a '#' in column 1.
|
---|
103 | */
|
---|
104 |
|
---|
105 | /* inetd rules for passing file descriptors to children
|
---|
106 | * (http://www.freebsd.org/cgi/man.cgi?query=inetd):
|
---|
107 | *
|
---|
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.
|
---|
124 | *
|
---|
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.
|
---|
133 | */
|
---|
134 |
|
---|
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.
|
---|
140 | */
|
---|
141 |
|
---|
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)
|
---|
147 | * setuid()
|
---|
148 | * 2) group is specified:
|
---|
149 | * a) user = root: setgid(specified group)
|
---|
150 | * NO initgroups()
|
---|
151 | * NO setuid()
|
---|
152 | * b) other: initgroups(name, specified group)
|
---|
153 | * setgid(specified group)
|
---|
154 | * setuid()
|
---|
155 | */
|
---|
156 |
|
---|
157 | #include <syslog.h>
|
---|
158 | #include <sys/un.h>
|
---|
159 |
|
---|
160 | #include "libbb.h"
|
---|
161 |
|
---|
162 | #if ENABLE_FEATURE_INETD_RPC
|
---|
163 | #include <rpc/rpc.h>
|
---|
164 | #include <rpc/pmap_clnt.h>
|
---|
165 | #endif
|
---|
166 |
|
---|
167 | #if !BB_MMU
|
---|
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
|
---|
172 | #endif
|
---|
173 |
|
---|
174 | #define _PATH_INETDPID "/var/run/inetd.pid"
|
---|
175 |
|
---|
176 | #define CNT_INTERVAL 60 /* servers in CNT_INTERVAL sec. */
|
---|
177 | #define RETRYTIME 60 /* retry after bind or server fail */
|
---|
178 |
|
---|
179 | // TODO: explain, or get rid of setrlimit games
|
---|
180 |
|
---|
181 | #ifndef RLIMIT_NOFILE
|
---|
182 | #define RLIMIT_NOFILE RLIMIT_OFILE
|
---|
183 | #endif
|
---|
184 |
|
---|
185 | #ifndef OPEN_MAX
|
---|
186 | #define OPEN_MAX 64
|
---|
187 | #endif
|
---|
188 |
|
---|
189 | /* Reserve some descriptors, 3 stdio + at least: 1 log, 1 conf. file */
|
---|
190 | #define FD_MARGIN 8
|
---|
191 |
|
---|
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
|
---|
198 | #endif
|
---|
199 |
|
---|
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)
|
---|
214 | #else
|
---|
215 | #define is_rpc_service(sep) 0
|
---|
216 | #endif
|
---|
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 */
|
---|
231 | #endif
|
---|
232 | struct servtab_t *se_next;
|
---|
233 | len_and_sockaddr *se_lsa;
|
---|
234 | char *se_program; /* server program */
|
---|
235 | #define MAXARGV 20
|
---|
236 | char *se_argv[MAXARGV + 1]; /* program arguments */
|
---|
237 | } servtab_t;
|
---|
238 |
|
---|
239 | #ifdef INETD_BUILTINS_ENABLED
|
---|
240 | /* Echo received data */
|
---|
241 | #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_ECHO
|
---|
242 | static void FAST_FUNC echo_stream(int, servtab_t *);
|
---|
243 | static void FAST_FUNC echo_dg(int, servtab_t *);
|
---|
244 | #endif
|
---|
245 | /* Internet /dev/null */
|
---|
246 | #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DISCARD
|
---|
247 | static void FAST_FUNC discard_stream(int, servtab_t *);
|
---|
248 | static void FAST_FUNC discard_dg(int, servtab_t *);
|
---|
249 | #endif
|
---|
250 | /* Return 32 bit time since 1900 */
|
---|
251 | #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_TIME
|
---|
252 | static void FAST_FUNC machtime_stream(int, servtab_t *);
|
---|
253 | static void FAST_FUNC machtime_dg(int, servtab_t *);
|
---|
254 | #endif
|
---|
255 | /* Return human-readable time */
|
---|
256 | #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DAYTIME
|
---|
257 | static void FAST_FUNC daytime_stream(int, servtab_t *);
|
---|
258 | static void FAST_FUNC daytime_dg(int, servtab_t *);
|
---|
259 | #endif
|
---|
260 | /* Familiar character generator */
|
---|
261 | #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_CHARGEN
|
---|
262 | static void FAST_FUNC chargen_stream(int, servtab_t *);
|
---|
263 | static void FAST_FUNC chargen_dg(int, servtab_t *);
|
---|
264 | #endif
|
---|
265 |
|
---|
266 | struct builtin {
|
---|
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 *) FAST_FUNC;
|
---|
271 | void (*bi_dgram_fn)(int, servtab_t *) FAST_FUNC;
|
---|
272 | };
|
---|
273 |
|
---|
274 | static const struct builtin builtins[] = {
|
---|
275 | #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_ECHO
|
---|
276 | { "echo", 1, echo_stream, echo_dg },
|
---|
277 | #endif
|
---|
278 | #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DISCARD
|
---|
279 | { "discard", 1, discard_stream, discard_dg },
|
---|
280 | #endif
|
---|
281 | #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_CHARGEN
|
---|
282 | { "chargen", 1, chargen_stream, chargen_dg },
|
---|
283 | #endif
|
---|
284 | #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_TIME
|
---|
285 | { "time", 0, machtime_stream, machtime_dg },
|
---|
286 | #endif
|
---|
287 | #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DAYTIME
|
---|
288 | { "daytime", 0, daytime_stream, daytime_dg },
|
---|
289 | #endif
|
---|
290 | };
|
---|
291 | #endif /* INETD_BUILTINS_ENABLED */
|
---|
292 |
|
---|
293 | struct globals {
|
---|
294 | rlim_t rlim_ofile_cur;
|
---|
295 | struct rlimit rlim_ofile;
|
---|
296 | servtab_t *serv_list;
|
---|
297 | int global_queuelen;
|
---|
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 */
|
---|
301 | int prev_maxsock;
|
---|
302 | unsigned max_concurrency;
|
---|
303 | smallint alarm_armed;
|
---|
304 | uid_t real_uid; /* user ID who ran us */
|
---|
305 | const char *config_filename;
|
---|
306 | parser_t *parser;
|
---|
307 | char *default_local_hostname;
|
---|
308 | #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_CHARGEN
|
---|
309 | char *end_ring;
|
---|
310 | char *ring_pos;
|
---|
311 | char ring[128];
|
---|
312 | #endif
|
---|
313 | fd_set allsock;
|
---|
314 | /* Used in next_line(), and as scratch read buffer */
|
---|
315 | char line[256]; /* _at least_ 256, see LINE_SIZE */
|
---|
316 | } FIX_ALIASING;
|
---|
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];
|
---|
321 | };
|
---|
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"; \
|
---|
345 | } while (0)
|
---|
346 |
|
---|
347 | static void maybe_close(int fd)
|
---|
348 | {
|
---|
349 | if (fd >= 0)
|
---|
350 | close(fd);
|
---|
351 | }
|
---|
352 |
|
---|
353 | // TODO: move to libbb?
|
---|
354 | static len_and_sockaddr *xzalloc_lsa(int family)
|
---|
355 | {
|
---|
356 | len_and_sockaddr *lsa;
|
---|
357 | int sz;
|
---|
358 |
|
---|
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);
|
---|
365 | #endif
|
---|
366 | lsa = xzalloc(LSA_LEN_SIZE + sz);
|
---|
367 | lsa->len = sz;
|
---|
368 | lsa->u.sa.sa_family = family;
|
---|
369 | return lsa;
|
---|
370 | }
|
---|
371 |
|
---|
372 | static void rearm_alarm(void)
|
---|
373 | {
|
---|
374 | if (!alarm_armed) {
|
---|
375 | alarm_armed = 1;
|
---|
376 | alarm(RETRYTIME);
|
---|
377 | }
|
---|
378 | }
|
---|
379 |
|
---|
380 | static void block_CHLD_HUP_ALRM(sigset_t *m)
|
---|
381 | {
|
---|
382 | sigemptyset(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 */
|
---|
387 | }
|
---|
388 |
|
---|
389 | static void restore_sigmask(sigset_t *m)
|
---|
390 | {
|
---|
391 | sigprocmask(SIG_SETMASK, m, NULL);
|
---|
392 | }
|
---|
393 |
|
---|
394 | #if ENABLE_FEATURE_INETD_RPC
|
---|
395 | static void register_rpc(servtab_t *sep)
|
---|
396 | {
|
---|
397 | int n;
|
---|
398 | struct sockaddr_in ir_sin;
|
---|
399 | socklen_t size;
|
---|
400 |
|
---|
401 | size = sizeof(ir_sin);
|
---|
402 | if (getsockname(sep->se_fd, (struct sockaddr *) &ir_sin, &size) < 0) {
|
---|
403 | bb_perror_msg("getsockname");
|
---|
404 | return;
|
---|
405 | }
|
---|
406 |
|
---|
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));
|
---|
413 | }
|
---|
414 | }
|
---|
415 |
|
---|
416 | static void unregister_rpc(servtab_t *sep)
|
---|
417 | {
|
---|
418 | int n;
|
---|
419 |
|
---|
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);
|
---|
423 | }
|
---|
424 | }
|
---|
425 | #endif /* FEATURE_INETD_RPC */
|
---|
426 |
|
---|
427 | static void bump_nofile(void)
|
---|
428 | {
|
---|
429 | enum { FD_CHUNK = 32 };
|
---|
430 | struct rlimit rl;
|
---|
431 |
|
---|
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",
|
---|
438 | (int) rl.rlim_cur);
|
---|
439 | return;
|
---|
440 | }
|
---|
441 |
|
---|
442 | if (setrlimit(RLIMIT_NOFILE, &rl) < 0) {
|
---|
443 | bb_perror_msg("setrlimit");
|
---|
444 | return;
|
---|
445 | }
|
---|
446 |
|
---|
447 | rlim_ofile_cur = rl.rlim_cur;
|
---|
448 | }
|
---|
449 |
|
---|
450 | static void remove_fd_from_set(int fd)
|
---|
451 | {
|
---|
452 | if (fd >= 0) {
|
---|
453 | FD_CLR(fd, &allsock);
|
---|
454 | maxsock = -1;
|
---|
455 | }
|
---|
456 | }
|
---|
457 |
|
---|
458 | static void add_fd_to_set(int fd)
|
---|
459 | {
|
---|
460 | if (fd >= 0) {
|
---|
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)
|
---|
465 | bump_nofile();
|
---|
466 | }
|
---|
467 | }
|
---|
468 | }
|
---|
469 |
|
---|
470 | static void recalculate_maxsock(void)
|
---|
471 | {
|
---|
472 | int fd = 0;
|
---|
473 |
|
---|
474 | /* We may have no services, in this case maxsock should still be >= 0
|
---|
475 | * (code elsewhere is not happy with maxsock == -1) */
|
---|
476 | maxsock = 0;
|
---|
477 | while (fd <= prev_maxsock) {
|
---|
478 | if (FD_ISSET(fd, &allsock))
|
---|
479 | maxsock = fd;
|
---|
480 | fd++;
|
---|
481 | }
|
---|
482 | prev_maxsock = maxsock;
|
---|
483 | if ((rlim_t)maxsock > rlim_ofile_cur - FD_MARGIN)
|
---|
484 | bump_nofile();
|
---|
485 | }
|
---|
486 |
|
---|
487 | static void prepare_socket_fd(servtab_t *sep)
|
---|
488 | {
|
---|
489 | int r, fd;
|
---|
490 |
|
---|
491 | fd = socket(sep->se_family, sep->se_socktype, 0);
|
---|
492 | if (fd < 0) {
|
---|
493 | bb_perror_msg("socket");
|
---|
494 | return;
|
---|
495 | }
|
---|
496 | setsockopt_reuseaddr(fd);
|
---|
497 |
|
---|
498 | #if ENABLE_FEATURE_INETD_RPC
|
---|
499 | if (is_rpc_service(sep)) {
|
---|
500 | struct passwd *pwd;
|
---|
501 |
|
---|
502 | /* zero out the port for all RPC services; let bind()
|
---|
503 | * find one. */
|
---|
504 | set_nport(sep->se_lsa, 0);
|
---|
505 |
|
---|
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
|
---|
510 | && pwd->pw_uid == 0
|
---|
511 | ) {
|
---|
512 | r = bindresvport(fd, &sep->se_lsa->u.sin);
|
---|
513 | } else {
|
---|
514 | r = bind(fd, &sep->se_lsa->u.sa, sep->se_lsa->len);
|
---|
515 | }
|
---|
516 | if (r == 0) {
|
---|
517 | int saveerrno = errno;
|
---|
518 | /* update lsa with port# */
|
---|
519 | getsockname(fd, &sep->se_lsa->u.sa, &sep->se_lsa->len);
|
---|
520 | errno = saveerrno;
|
---|
521 | }
|
---|
522 | } else
|
---|
523 | #endif
|
---|
524 | {
|
---|
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);
|
---|
529 | }
|
---|
530 | r = bind(fd, &sep->se_lsa->u.sa, sep->se_lsa->len);
|
---|
531 | }
|
---|
532 | if (r < 0) {
|
---|
533 | bb_perror_msg("%s/%s: bind",
|
---|
534 | sep->se_service, sep->se_proto);
|
---|
535 | close(fd);
|
---|
536 | rearm_alarm();
|
---|
537 | return;
|
---|
538 | }
|
---|
539 | if (sep->se_socktype == SOCK_STREAM)
|
---|
540 | listen(fd, global_queuelen);
|
---|
541 |
|
---|
542 | add_fd_to_set(fd);
|
---|
543 | sep->se_fd = fd;
|
---|
544 | }
|
---|
545 |
|
---|
546 | static int reopen_config_file(void)
|
---|
547 | {
|
---|
548 | free(default_local_hostname);
|
---|
549 | default_local_hostname = xstrdup("*");
|
---|
550 | if (parser != NULL)
|
---|
551 | config_close(parser);
|
---|
552 | parser = config_open(config_filename);
|
---|
553 | return (parser != NULL);
|
---|
554 | }
|
---|
555 |
|
---|
556 | static void close_config_file(void)
|
---|
557 | {
|
---|
558 | if (parser) {
|
---|
559 | config_close(parser);
|
---|
560 | parser = NULL;
|
---|
561 | }
|
---|
562 | }
|
---|
563 |
|
---|
564 | static void free_servtab_strings(servtab_t *cp)
|
---|
565 | {
|
---|
566 | int i;
|
---|
567 |
|
---|
568 | free(cp->se_local_hostname);
|
---|
569 | free(cp->se_service);
|
---|
570 | free(cp->se_proto);
|
---|
571 | free(cp->se_user);
|
---|
572 | free(cp->se_group);
|
---|
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]);
|
---|
577 | }
|
---|
578 |
|
---|
579 | static servtab_t *new_servtab(void)
|
---|
580 | {
|
---|
581 | servtab_t *newtab = xzalloc(sizeof(servtab_t));
|
---|
582 | newtab->se_fd = -1; /* paranoia */
|
---|
583 | return newtab;
|
---|
584 | }
|
---|
585 |
|
---|
586 | static servtab_t *dup_servtab(servtab_t *sep)
|
---|
587 | {
|
---|
588 | servtab_t *newtab;
|
---|
589 | int argc;
|
---|
590 |
|
---|
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 */
|
---|
604 |
|
---|
605 | return newtab;
|
---|
606 | }
|
---|
607 |
|
---|
608 | /* gcc generates much more code if this is inlined */
|
---|
609 | static servtab_t *parse_one_line(void)
|
---|
610 | {
|
---|
611 | int argc;
|
---|
612 | char *token[6+MAXARGV];
|
---|
613 | char *p, *arg;
|
---|
614 | char *hostdelim;
|
---|
615 | servtab_t *sep;
|
---|
616 | servtab_t *nsep;
|
---|
617 | new:
|
---|
618 | sep = new_servtab();
|
---|
619 | more:
|
---|
620 | argc = config_read(parser, token, 6+MAXARGV, 1, "# \t", PARSE_NORMAL);
|
---|
621 | if (!argc) {
|
---|
622 | free(sep);
|
---|
623 | return NULL;
|
---|
624 | }
|
---|
625 |
|
---|
626 | /* [host:]service socktype proto wait user[:group] prog [args] */
|
---|
627 | /* Check for "host:...." line */
|
---|
628 | arg = token[0];
|
---|
629 | hostdelim = strrchr(arg, ':');
|
---|
630 | if (hostdelim) {
|
---|
631 | *hostdelim = '\0';
|
---|
632 | sep->se_local_hostname = xstrdup(arg);
|
---|
633 | arg = hostdelim + 1;
|
---|
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;
|
---|
639 | goto more;
|
---|
640 | }
|
---|
641 | } else
|
---|
642 | sep->se_local_hostname = xstrdup(default_local_hostname);
|
---|
643 |
|
---|
644 | /* service socktype proto wait user[:group] prog [args] */
|
---|
645 | sep->se_service = xstrdup(arg);
|
---|
646 |
|
---|
647 | /* socktype proto wait user[:group] prog [args] */
|
---|
648 | if (argc < 6) {
|
---|
649 | parse_err:
|
---|
650 | bb_error_msg("parse error on line %u, line is ignored",
|
---|
651 | parser->lineno);
|
---|
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: */
|
---|
656 | free(sep);
|
---|
657 | goto new;
|
---|
658 | }
|
---|
659 |
|
---|
660 | {
|
---|
661 | static const int8_t SOCK_xxx[] ALIGN1 = {
|
---|
662 | -1,
|
---|
663 | SOCK_STREAM, SOCK_DGRAM, SOCK_RDM,
|
---|
664 | SOCK_SEQPACKET, SOCK_RAW
|
---|
665 | };
|
---|
666 | sep->se_socktype = SOCK_xxx[1 + index_in_strings(
|
---|
667 | "stream""\0" "dgram""\0" "rdm""\0"
|
---|
668 | "seqpacket""\0" "raw""\0"
|
---|
669 | , token[1])];
|
---|
670 | }
|
---|
671 |
|
---|
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;
|
---|
676 | } else {
|
---|
677 | char *six;
|
---|
678 | sep->se_family = AF_INET;
|
---|
679 | six = last_char_is(arg, '6');
|
---|
680 | if (six) {
|
---|
681 | #if ENABLE_FEATURE_IPV6
|
---|
682 | *six = '\0';
|
---|
683 | sep->se_family = AF_INET6;
|
---|
684 | #else
|
---|
685 | bb_error_msg("%s: no support for IPv6", sep->se_proto);
|
---|
686 | goto parse_err;
|
---|
687 | #endif
|
---|
688 | }
|
---|
689 | if (strncmp(arg, "rpc/", 4) == 0) {
|
---|
690 | #if ENABLE_FEATURE_INETD_RPC
|
---|
691 | unsigned n;
|
---|
692 | arg += 4;
|
---|
693 | p = strchr(sep->se_service, '/');
|
---|
694 | if (p == NULL) {
|
---|
695 | bb_error_msg("no rpc version: '%s'", sep->se_service);
|
---|
696 | goto parse_err;
|
---|
697 | }
|
---|
698 | *p++ = '\0';
|
---|
699 | n = bb_strtou(p, &p, 10);
|
---|
700 | if (n > INT_MAX) {
|
---|
701 | bad_ver_spec:
|
---|
702 | bb_error_msg("bad rpc version");
|
---|
703 | goto parse_err;
|
---|
704 | }
|
---|
705 | sep->se_rpcver_lo = sep->se_rpcver_hi = n;
|
---|
706 | if (*p == '-') {
|
---|
707 | p++;
|
---|
708 | n = bb_strtou(p, &p, 10);
|
---|
709 | if (n > INT_MAX || (int)n < sep->se_rpcver_lo)
|
---|
710 | goto bad_ver_spec;
|
---|
711 | sep->se_rpcver_hi = n;
|
---|
712 | }
|
---|
713 | if (*p != '\0')
|
---|
714 | goto bad_ver_spec;
|
---|
715 | #else
|
---|
716 | bb_error_msg("no support for rpc services");
|
---|
717 | goto parse_err;
|
---|
718 | #endif
|
---|
719 | }
|
---|
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 */
|
---|
725 | if (six)
|
---|
726 | *six = '6';
|
---|
727 | if (!sep->se_proto_no) /* not tcp/udp?? */
|
---|
728 | goto parse_err;
|
---|
729 | }
|
---|
730 |
|
---|
731 | /* [no]wait[.max] user[:group] prog [args] */
|
---|
732 | arg = token[3];
|
---|
733 | sep->se_max = max_concurrency;
|
---|
734 | p = strchr(arg, '.');
|
---|
735 | if (p) {
|
---|
736 | *p++ = '\0';
|
---|
737 | sep->se_max = bb_strtou(p, NULL, 10);
|
---|
738 | if (errno)
|
---|
739 | goto parse_err;
|
---|
740 | }
|
---|
741 | sep->se_wait = (arg[0] != 'n' || arg[1] != 'o');
|
---|
742 | if (!sep->se_wait) /* "no" seen */
|
---|
743 | arg += 2;
|
---|
744 | if (strcmp(arg, "wait") != 0)
|
---|
745 | goto parse_err;
|
---|
746 |
|
---|
747 | /* user[:group] prog [args] */
|
---|
748 | sep->se_user = xstrdup(token[4]);
|
---|
749 | arg = strchr(sep->se_user, '.');
|
---|
750 | if (arg == NULL)
|
---|
751 | arg = strchr(sep->se_user, ':');
|
---|
752 | if (arg) {
|
---|
753 | *arg++ = '\0';
|
---|
754 | sep->se_group = xstrdup(arg);
|
---|
755 | }
|
---|
756 |
|
---|
757 | /* prog [args] */
|
---|
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)
|
---|
764 | ) {
|
---|
765 | unsigned i;
|
---|
766 | for (i = 0; i < ARRAY_SIZE(builtins); i++)
|
---|
767 | if (strncmp(builtins[i].bi_service7, sep->se_service, 7) == 0)
|
---|
768 | goto found_bi;
|
---|
769 | bb_error_msg("unknown internal service %s", sep->se_service);
|
---|
770 | goto parse_err;
|
---|
771 | found_bi:
|
---|
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))
|
---|
775 | goto parse_err;
|
---|
776 | }
|
---|
777 | #endif
|
---|
778 | argc = 0;
|
---|
779 | while ((arg = token[6+argc]) != NULL && argc < MAXARGV)
|
---|
780 | sep->se_argv[argc++] = xstrdup(arg);
|
---|
781 | /* Some inetd.conf files have no argv's, not even argv[0].
|
---|
782 | * Fix them up.
|
---|
783 | * (Technically, programs can be execed with argv[0] = NULL,
|
---|
784 | * but many programs do not like that at all) */
|
---|
785 | if (argc == 0)
|
---|
786 | sep->se_argv[0] = xstrdup(sep->se_program);
|
---|
787 |
|
---|
788 | /* catch mixups. "<service> stream udp ..." == wtf */
|
---|
789 | if (sep->se_socktype == SOCK_STREAM) {
|
---|
790 | if (sep->se_proto_no == IPPROTO_UDP)
|
---|
791 | goto parse_err;
|
---|
792 | }
|
---|
793 | if (sep->se_socktype == SOCK_DGRAM) {
|
---|
794 | if (sep->se_proto_no == IPPROTO_TCP)
|
---|
795 | goto parse_err;
|
---|
796 | }
|
---|
797 |
|
---|
798 | // bb_info_msg(
|
---|
799 | // "ENTRY[%s][%s][%s][%d][%d][%d][%d][%d][%s][%s][%s]",
|
---|
800 | // sep->se_local_hostname, sep->se_service, sep->se_proto, sep->se_wait, sep->se_proto_no,
|
---|
801 | // sep->se_max, sep->se_count, sep->se_time, sep->se_user, sep->se_group, sep->se_program);
|
---|
802 |
|
---|
803 | /* check if the hostname specifier is a comma separated list
|
---|
804 | * of hostnames. we'll make new entries for each address. */
|
---|
805 | while ((hostdelim = strrchr(sep->se_local_hostname, ',')) != NULL) {
|
---|
806 | nsep = dup_servtab(sep);
|
---|
807 | /* NUL terminate the hostname field of the existing entry,
|
---|
808 | * and make a dup for the new entry. */
|
---|
809 | *hostdelim++ = '\0';
|
---|
810 | nsep->se_local_hostname = xstrdup(hostdelim);
|
---|
811 | nsep->se_next = sep->se_next;
|
---|
812 | sep->se_next = nsep;
|
---|
813 | }
|
---|
814 |
|
---|
815 | /* was doing it here: */
|
---|
816 | /* DNS resolution, create copies for each IP address */
|
---|
817 | /* IPv6-ization destroyed it :( */
|
---|
818 |
|
---|
819 | return sep;
|
---|
820 | }
|
---|
821 |
|
---|
822 | static servtab_t *insert_in_servlist(servtab_t *cp)
|
---|
823 | {
|
---|
824 | servtab_t *sep;
|
---|
825 | sigset_t omask;
|
---|
826 |
|
---|
827 | sep = new_servtab();
|
---|
828 | *sep = *cp; /* struct copy */
|
---|
829 | sep->se_fd = -1;
|
---|
830 | #if ENABLE_FEATURE_INETD_RPC
|
---|
831 | sep->se_rpcprog = -1;
|
---|
832 | #endif
|
---|
833 | block_CHLD_HUP_ALRM(&omask);
|
---|
834 | sep->se_next = serv_list;
|
---|
835 | serv_list = sep;
|
---|
836 | restore_sigmask(&omask);
|
---|
837 | return sep;
|
---|
838 | }
|
---|
839 |
|
---|
840 | static int same_serv_addr_proto(servtab_t *old, servtab_t *new)
|
---|
841 | {
|
---|
842 | if (strcmp(old->se_local_hostname, new->se_local_hostname) != 0)
|
---|
843 | return 0;
|
---|
844 | if (strcmp(old->se_service, new->se_service) != 0)
|
---|
845 | return 0;
|
---|
846 | if (strcmp(old->se_proto, new->se_proto) != 0)
|
---|
847 | return 0;
|
---|
848 | return 1;
|
---|
849 | }
|
---|
850 |
|
---|
851 | static void reread_config_file(int sig UNUSED_PARAM)
|
---|
852 | {
|
---|
853 | servtab_t *sep, *cp, **sepp;
|
---|
854 | len_and_sockaddr *lsa;
|
---|
855 | sigset_t omask;
|
---|
856 | unsigned n;
|
---|
857 | uint16_t port;
|
---|
858 | int save_errno = errno;
|
---|
859 |
|
---|
860 | if (!reopen_config_file())
|
---|
861 | goto ret;
|
---|
862 | for (sep = serv_list; sep; sep = sep->se_next)
|
---|
863 | sep->se_checked = 0;
|
---|
864 |
|
---|
865 | goto first_line;
|
---|
866 | while (1) {
|
---|
867 | if (cp == NULL) {
|
---|
868 | first_line:
|
---|
869 | cp = parse_one_line();
|
---|
870 | if (cp == NULL)
|
---|
871 | break;
|
---|
872 | }
|
---|
873 | for (sep = serv_list; sep; sep = sep->se_next)
|
---|
874 | if (same_serv_addr_proto(sep, cp))
|
---|
875 | goto equal_servtab;
|
---|
876 | /* not an "equal" servtab */
|
---|
877 | sep = insert_in_servlist(cp);
|
---|
878 | goto after_check;
|
---|
879 | equal_servtab:
|
---|
880 | {
|
---|
881 | int i;
|
---|
882 |
|
---|
883 | block_CHLD_HUP_ALRM(&omask);
|
---|
884 | #if ENABLE_FEATURE_INETD_RPC
|
---|
885 | if (is_rpc_service(sep))
|
---|
886 | unregister_rpc(sep);
|
---|
887 | sep->se_rpcver_lo = cp->se_rpcver_lo;
|
---|
888 | sep->se_rpcver_hi = cp->se_rpcver_hi;
|
---|
889 | #endif
|
---|
890 | if (cp->se_wait == 0) {
|
---|
891 | /* New config says "nowait". If old one
|
---|
892 | * was "wait", we currently may be waiting
|
---|
893 | * for a child (and not accepting connects).
|
---|
894 | * Stop waiting, start listening again.
|
---|
895 | * (if it's not true, this op is harmless) */
|
---|
896 | add_fd_to_set(sep->se_fd);
|
---|
897 | }
|
---|
898 | sep->se_wait = cp->se_wait;
|
---|
899 | sep->se_max = cp->se_max;
|
---|
900 | /* string fields need more love - we don't want to leak them */
|
---|
901 | #define SWAP(type, a, b) do { type c = (type)a; a = (type)b; b = (type)c; } while (0)
|
---|
902 | SWAP(char*, sep->se_user, cp->se_user);
|
---|
903 | SWAP(char*, sep->se_group, cp->se_group);
|
---|
904 | SWAP(char*, sep->se_program, cp->se_program);
|
---|
905 | for (i = 0; i < MAXARGV; i++)
|
---|
906 | SWAP(char*, sep->se_argv[i], cp->se_argv[i]);
|
---|
907 | #undef SWAP
|
---|
908 | restore_sigmask(&omask);
|
---|
909 | free_servtab_strings(cp);
|
---|
910 | }
|
---|
911 | after_check:
|
---|
912 | /* cp->string_fields are consumed by insert_in_servlist()
|
---|
913 | * or freed at this point, cp itself is not yet freed. */
|
---|
914 | sep->se_checked = 1;
|
---|
915 |
|
---|
916 | /* create new len_and_sockaddr */
|
---|
917 | switch (sep->se_family) {
|
---|
918 | struct sockaddr_un *sun;
|
---|
919 | case AF_UNIX:
|
---|
920 | lsa = xzalloc_lsa(AF_UNIX);
|
---|
921 | sun = (struct sockaddr_un*)&lsa->u.sa;
|
---|
922 | safe_strncpy(sun->sun_path, sep->se_service, sizeof(sun->sun_path));
|
---|
923 | break;
|
---|
924 |
|
---|
925 | default: /* case AF_INET, case AF_INET6 */
|
---|
926 | n = bb_strtou(sep->se_service, NULL, 10);
|
---|
927 | #if ENABLE_FEATURE_INETD_RPC
|
---|
928 | if (is_rpc_service(sep)) {
|
---|
929 | sep->se_rpcprog = n;
|
---|
930 | if (errno) { /* se_service is not numeric */
|
---|
931 | struct rpcent *rp = getrpcbyname(sep->se_service);
|
---|
932 | if (rp == NULL) {
|
---|
933 | bb_error_msg("%s: unknown rpc service", sep->se_service);
|
---|
934 | goto next_cp;
|
---|
935 | }
|
---|
936 | sep->se_rpcprog = rp->r_number;
|
---|
937 | }
|
---|
938 | if (sep->se_fd == -1)
|
---|
939 | prepare_socket_fd(sep);
|
---|
940 | if (sep->se_fd != -1)
|
---|
941 | register_rpc(sep);
|
---|
942 | goto next_cp;
|
---|
943 | }
|
---|
944 | #endif
|
---|
945 | /* what port to listen on? */
|
---|
946 | port = htons(n);
|
---|
947 | if (errno || n > 0xffff) { /* se_service is not numeric */
|
---|
948 | char protoname[4];
|
---|
949 | struct servent *sp;
|
---|
950 | /* can result only in "tcp" or "udp": */
|
---|
951 | safe_strncpy(protoname, sep->se_proto, 4);
|
---|
952 | sp = getservbyname(sep->se_service, protoname);
|
---|
953 | if (sp == NULL) {
|
---|
954 | bb_error_msg("%s/%s: unknown service",
|
---|
955 | sep->se_service, sep->se_proto);
|
---|
956 | goto next_cp;
|
---|
957 | }
|
---|
958 | port = sp->s_port;
|
---|
959 | }
|
---|
960 | if (LONE_CHAR(sep->se_local_hostname, '*')) {
|
---|
961 | lsa = xzalloc_lsa(sep->se_family);
|
---|
962 | set_nport(lsa, port);
|
---|
963 | } else {
|
---|
964 | lsa = host_and_af2sockaddr(sep->se_local_hostname,
|
---|
965 | ntohs(port), sep->se_family);
|
---|
966 | if (!lsa) {
|
---|
967 | bb_error_msg("%s/%s: unknown host '%s'",
|
---|
968 | sep->se_service, sep->se_proto,
|
---|
969 | sep->se_local_hostname);
|
---|
970 | goto next_cp;
|
---|
971 | }
|
---|
972 | }
|
---|
973 | break;
|
---|
974 | } /* end of "switch (sep->se_family)" */
|
---|
975 |
|
---|
976 | /* did lsa change? Then close/open */
|
---|
977 | if (sep->se_lsa == NULL
|
---|
978 | || lsa->len != sep->se_lsa->len
|
---|
979 | || memcmp(&lsa->u.sa, &sep->se_lsa->u.sa, lsa->len) != 0
|
---|
980 | ) {
|
---|
981 | remove_fd_from_set(sep->se_fd);
|
---|
982 | maybe_close(sep->se_fd);
|
---|
983 | free(sep->se_lsa);
|
---|
984 | sep->se_lsa = lsa;
|
---|
985 | sep->se_fd = -1;
|
---|
986 | } else {
|
---|
987 | free(lsa);
|
---|
988 | }
|
---|
989 | if (sep->se_fd == -1)
|
---|
990 | prepare_socket_fd(sep);
|
---|
991 | next_cp:
|
---|
992 | sep = cp->se_next;
|
---|
993 | free(cp);
|
---|
994 | cp = sep;
|
---|
995 | } /* end of "while (1) parse lines" */
|
---|
996 | close_config_file();
|
---|
997 |
|
---|
998 | /* Purge anything not looked at above - these are stale entries,
|
---|
999 | * new config file doesnt have them. */
|
---|
1000 | block_CHLD_HUP_ALRM(&omask);
|
---|
1001 | sepp = &serv_list;
|
---|
1002 | while ((sep = *sepp)) {
|
---|
1003 | if (sep->se_checked) {
|
---|
1004 | sepp = &sep->se_next;
|
---|
1005 | continue;
|
---|
1006 | }
|
---|
1007 | *sepp = sep->se_next;
|
---|
1008 | remove_fd_from_set(sep->se_fd);
|
---|
1009 | maybe_close(sep->se_fd);
|
---|
1010 | #if ENABLE_FEATURE_INETD_RPC
|
---|
1011 | if (is_rpc_service(sep))
|
---|
1012 | unregister_rpc(sep);
|
---|
1013 | #endif
|
---|
1014 | if (sep->se_family == AF_UNIX)
|
---|
1015 | unlink(sep->se_service);
|
---|
1016 | free_servtab_strings(sep);
|
---|
1017 | free(sep);
|
---|
1018 | }
|
---|
1019 | restore_sigmask(&omask);
|
---|
1020 | ret:
|
---|
1021 | errno = save_errno;
|
---|
1022 | }
|
---|
1023 |
|
---|
1024 | static void reap_child(int sig UNUSED_PARAM)
|
---|
1025 | {
|
---|
1026 | pid_t pid;
|
---|
1027 | int status;
|
---|
1028 | servtab_t *sep;
|
---|
1029 | int save_errno = errno;
|
---|
1030 |
|
---|
1031 | for (;;) {
|
---|
1032 | pid = wait_any_nohang(&status);
|
---|
1033 | if (pid <= 0)
|
---|
1034 | break;
|
---|
1035 | for (sep = serv_list; sep; sep = sep->se_next) {
|
---|
1036 | if (sep->se_wait != pid)
|
---|
1037 | continue;
|
---|
1038 | /* One of our "wait" services */
|
---|
1039 | if (WIFEXITED(status) && WEXITSTATUS(status))
|
---|
1040 | bb_error_msg("%s: exit status %u",
|
---|
1041 | sep->se_program, WEXITSTATUS(status));
|
---|
1042 | else if (WIFSIGNALED(status))
|
---|
1043 | bb_error_msg("%s: exit signal %u",
|
---|
1044 | sep->se_program, WTERMSIG(status));
|
---|
1045 | sep->se_wait = 1;
|
---|
1046 | add_fd_to_set(sep->se_fd);
|
---|
1047 | break;
|
---|
1048 | }
|
---|
1049 | }
|
---|
1050 | errno = save_errno;
|
---|
1051 | }
|
---|
1052 |
|
---|
1053 | static void retry_network_setup(int sig UNUSED_PARAM)
|
---|
1054 | {
|
---|
1055 | int save_errno = errno;
|
---|
1056 | servtab_t *sep;
|
---|
1057 |
|
---|
1058 | alarm_armed = 0;
|
---|
1059 | for (sep = serv_list; sep; sep = sep->se_next) {
|
---|
1060 | if (sep->se_fd == -1) {
|
---|
1061 | prepare_socket_fd(sep);
|
---|
1062 | #if ENABLE_FEATURE_INETD_RPC
|
---|
1063 | if (sep->se_fd != -1 && is_rpc_service(sep))
|
---|
1064 | register_rpc(sep);
|
---|
1065 | #endif
|
---|
1066 | }
|
---|
1067 | }
|
---|
1068 | errno = save_errno;
|
---|
1069 | }
|
---|
1070 |
|
---|
1071 | static void clean_up_and_exit(int sig UNUSED_PARAM)
|
---|
1072 | {
|
---|
1073 | servtab_t *sep;
|
---|
1074 |
|
---|
1075 | /* XXX signal race walking sep list */
|
---|
1076 | for (sep = serv_list; sep; sep = sep->se_next) {
|
---|
1077 | if (sep->se_fd == -1)
|
---|
1078 | continue;
|
---|
1079 |
|
---|
1080 | switch (sep->se_family) {
|
---|
1081 | case AF_UNIX:
|
---|
1082 | unlink(sep->se_service);
|
---|
1083 | break;
|
---|
1084 | default: /* case AF_INET, AF_INET6 */
|
---|
1085 | #if ENABLE_FEATURE_INETD_RPC
|
---|
1086 | if (sep->se_wait == 1 && is_rpc_service(sep))
|
---|
1087 | unregister_rpc(sep); /* XXX signal race */
|
---|
1088 | #endif
|
---|
1089 | break;
|
---|
1090 | }
|
---|
1091 | if (ENABLE_FEATURE_CLEAN_UP)
|
---|
1092 | close(sep->se_fd);
|
---|
1093 | }
|
---|
1094 | remove_pidfile(_PATH_INETDPID);
|
---|
1095 | exit(EXIT_SUCCESS);
|
---|
1096 | }
|
---|
1097 |
|
---|
1098 | int inetd_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
|
---|
1099 | int inetd_main(int argc UNUSED_PARAM, char **argv)
|
---|
1100 | {
|
---|
1101 | struct sigaction sa, saved_pipe_handler;
|
---|
1102 | servtab_t *sep, *sep2;
|
---|
1103 | struct passwd *pwd;
|
---|
1104 | struct group *grp = grp; /* for compiler */
|
---|
1105 | int opt;
|
---|
1106 | pid_t pid;
|
---|
1107 | sigset_t omask;
|
---|
1108 |
|
---|
1109 | INIT_G();
|
---|
1110 |
|
---|
1111 | real_uid = getuid();
|
---|
1112 | if (real_uid != 0) /* run by non-root user */
|
---|
1113 | config_filename = NULL;
|
---|
1114 |
|
---|
1115 | opt_complementary = "R+:q+"; /* -q N, -R N */
|
---|
1116 | opt = getopt32(argv, "R:feq:", &max_concurrency, &global_queuelen);
|
---|
1117 | argv += optind;
|
---|
1118 | //argc -= optind;
|
---|
1119 | if (argv[0])
|
---|
1120 | config_filename = argv[0];
|
---|
1121 | if (config_filename == NULL)
|
---|
1122 | bb_error_msg_and_die("non-root must specify config file");
|
---|
1123 | if (!(opt & 2))
|
---|
1124 | bb_daemonize_or_rexec(0, argv - optind);
|
---|
1125 | else
|
---|
1126 | bb_sanitize_stdio();
|
---|
1127 | if (!(opt & 4)) {
|
---|
1128 | /* LOG_NDELAY: connect to syslog daemon NOW.
|
---|
1129 | * Otherwise, we may open syslog socket
|
---|
1130 | * in vforked child, making opened fds and syslog()
|
---|
1131 | * internal state inconsistent.
|
---|
1132 | * This was observed to leak file descriptors. */
|
---|
1133 | openlog(applet_name, LOG_PID | LOG_NDELAY, LOG_DAEMON);
|
---|
1134 | logmode = LOGMODE_SYSLOG;
|
---|
1135 | }
|
---|
1136 |
|
---|
1137 | if (real_uid == 0) {
|
---|
1138 | /* run by root, ensure groups vector gets trashed */
|
---|
1139 | gid_t gid = getgid();
|
---|
1140 | setgroups(1, &gid);
|
---|
1141 | }
|
---|
1142 |
|
---|
1143 | write_pidfile(_PATH_INETDPID);
|
---|
1144 |
|
---|
1145 | /* never fails under Linux (except if you pass it bad arguments) */
|
---|
1146 | getrlimit(RLIMIT_NOFILE, &rlim_ofile);
|
---|
1147 | rlim_ofile_cur = rlim_ofile.rlim_cur;
|
---|
1148 | if (rlim_ofile_cur == RLIM_INFINITY) /* ! */
|
---|
1149 | rlim_ofile_cur = OPEN_MAX;
|
---|
1150 |
|
---|
1151 | memset(&sa, 0, sizeof(sa));
|
---|
1152 | /*sigemptyset(&sa.sa_mask); - memset did it */
|
---|
1153 | sigaddset(&sa.sa_mask, SIGALRM);
|
---|
1154 | sigaddset(&sa.sa_mask, SIGCHLD);
|
---|
1155 | sigaddset(&sa.sa_mask, SIGHUP);
|
---|
1156 | sa.sa_handler = retry_network_setup;
|
---|
1157 | sigaction_set(SIGALRM, &sa);
|
---|
1158 | sa.sa_handler = reread_config_file;
|
---|
1159 | sigaction_set(SIGHUP, &sa);
|
---|
1160 | sa.sa_handler = reap_child;
|
---|
1161 | sigaction_set(SIGCHLD, &sa);
|
---|
1162 | sa.sa_handler = clean_up_and_exit;
|
---|
1163 | sigaction_set(SIGTERM, &sa);
|
---|
1164 | sa.sa_handler = clean_up_and_exit;
|
---|
1165 | sigaction_set(SIGINT, &sa);
|
---|
1166 | sa.sa_handler = SIG_IGN;
|
---|
1167 | sigaction(SIGPIPE, &sa, &saved_pipe_handler);
|
---|
1168 |
|
---|
1169 | reread_config_file(SIGHUP); /* load config from file */
|
---|
1170 |
|
---|
1171 | for (;;) {
|
---|
1172 | int ready_fd_cnt;
|
---|
1173 | int ctrl, accepted_fd, new_udp_fd;
|
---|
1174 | fd_set readable;
|
---|
1175 |
|
---|
1176 | if (maxsock < 0)
|
---|
1177 | recalculate_maxsock();
|
---|
1178 |
|
---|
1179 | readable = allsock; /* struct copy */
|
---|
1180 | /* if there are no fds to wait on, we will block
|
---|
1181 | * until signal wakes us up (maxsock == 0, but readable
|
---|
1182 | * never contains fds 0 and 1...) */
|
---|
1183 | ready_fd_cnt = select(maxsock + 1, &readable, NULL, NULL, NULL);
|
---|
1184 | if (ready_fd_cnt < 0) {
|
---|
1185 | if (errno != EINTR) {
|
---|
1186 | bb_perror_msg("select");
|
---|
1187 | sleep(1);
|
---|
1188 | }
|
---|
1189 | continue;
|
---|
1190 | }
|
---|
1191 |
|
---|
1192 | for (sep = serv_list; ready_fd_cnt && sep; sep = sep->se_next) {
|
---|
1193 | if (sep->se_fd == -1 || !FD_ISSET(sep->se_fd, &readable))
|
---|
1194 | continue;
|
---|
1195 |
|
---|
1196 | ready_fd_cnt--;
|
---|
1197 | ctrl = sep->se_fd;
|
---|
1198 | accepted_fd = -1;
|
---|
1199 | new_udp_fd = -1;
|
---|
1200 | if (!sep->se_wait) {
|
---|
1201 | if (sep->se_socktype == SOCK_STREAM) {
|
---|
1202 | ctrl = accepted_fd = accept(sep->se_fd, NULL, NULL);
|
---|
1203 | if (ctrl < 0) {
|
---|
1204 | if (errno != EINTR)
|
---|
1205 | bb_perror_msg("accept (for %s)", sep->se_service);
|
---|
1206 | continue;
|
---|
1207 | }
|
---|
1208 | }
|
---|
1209 | /* "nowait" udp */
|
---|
1210 | if (sep->se_socktype == SOCK_DGRAM
|
---|
1211 | && sep->se_family != AF_UNIX
|
---|
1212 | ) {
|
---|
1213 | /* How udp "nowait" works:
|
---|
1214 | * child peeks at (received and buffered by kernel) UDP packet,
|
---|
1215 | * performs connect() on the socket so that it is linked only
|
---|
1216 | * to this peer. But this also affects parent, because descriptors
|
---|
1217 | * are shared after fork() a-la dup(). When parent performs
|
---|
1218 | * select(), it will see this descriptor connected to the peer (!)
|
---|
1219 | * and still readable, will act on it and mess things up
|
---|
1220 | * (can create many copies of same child, etc).
|
---|
1221 | * Parent must create and use new socket instead. */
|
---|
1222 | new_udp_fd = socket(sep->se_family, SOCK_DGRAM, 0);
|
---|
1223 | if (new_udp_fd < 0) { /* error: eat packet, forget about it */
|
---|
1224 | udp_err:
|
---|
1225 | recv(sep->se_fd, line, LINE_SIZE, MSG_DONTWAIT);
|
---|
1226 | continue;
|
---|
1227 | }
|
---|
1228 | setsockopt_reuseaddr(new_udp_fd);
|
---|
1229 | /* TODO: better do bind after vfork in parent,
|
---|
1230 | * so that we don't have two wildcard bound sockets
|
---|
1231 | * even for a brief moment? */
|
---|
1232 | if (bind(new_udp_fd, &sep->se_lsa->u.sa, sep->se_lsa->len) < 0) {
|
---|
1233 | close(new_udp_fd);
|
---|
1234 | goto udp_err;
|
---|
1235 | }
|
---|
1236 | }
|
---|
1237 | }
|
---|
1238 |
|
---|
1239 | block_CHLD_HUP_ALRM(&omask);
|
---|
1240 | pid = 0;
|
---|
1241 | #ifdef INETD_BUILTINS_ENABLED
|
---|
1242 | /* do we need to fork? */
|
---|
1243 | if (sep->se_builtin == NULL
|
---|
1244 | || (sep->se_socktype == SOCK_STREAM
|
---|
1245 | && sep->se_builtin->bi_fork))
|
---|
1246 | #endif
|
---|
1247 | {
|
---|
1248 | if (sep->se_max != 0) {
|
---|
1249 | if (++sep->se_count == 1)
|
---|
1250 | sep->se_time = monotonic_sec();
|
---|
1251 | else if (sep->se_count >= sep->se_max) {
|
---|
1252 | unsigned now = monotonic_sec();
|
---|
1253 | /* did we accumulate se_max connects too quickly? */
|
---|
1254 | if (now - sep->se_time <= CNT_INTERVAL) {
|
---|
1255 | bb_error_msg("%s/%s: too many connections, pausing",
|
---|
1256 | sep->se_service, sep->se_proto);
|
---|
1257 | remove_fd_from_set(sep->se_fd);
|
---|
1258 | close(sep->se_fd);
|
---|
1259 | sep->se_fd = -1;
|
---|
1260 | sep->se_count = 0;
|
---|
1261 | rearm_alarm(); /* will revive it in RETRYTIME sec */
|
---|
1262 | restore_sigmask(&omask);
|
---|
1263 | maybe_close(accepted_fd);
|
---|
1264 | continue; /* -> check next fd in fd set */
|
---|
1265 | }
|
---|
1266 | sep->se_count = 0;
|
---|
1267 | }
|
---|
1268 | }
|
---|
1269 | /* on NOMMU, streamed chargen
|
---|
1270 | * builtin wouldn't work, but it is
|
---|
1271 | * not allowed on NOMMU (ifdefed out) */
|
---|
1272 | #ifdef INETD_BUILTINS_ENABLED
|
---|
1273 | if (BB_MMU && sep->se_builtin)
|
---|
1274 | pid = fork();
|
---|
1275 | else
|
---|
1276 | #endif
|
---|
1277 | pid = vfork();
|
---|
1278 |
|
---|
1279 | if (pid < 0) { /* fork error */
|
---|
1280 | bb_perror_msg("vfork"+1);
|
---|
1281 | sleep(1);
|
---|
1282 | restore_sigmask(&omask);
|
---|
1283 | maybe_close(accepted_fd);
|
---|
1284 | continue; /* -> check next fd in fd set */
|
---|
1285 | }
|
---|
1286 | if (pid == 0)
|
---|
1287 | pid--; /* -1: "we did fork and we are child" */
|
---|
1288 | }
|
---|
1289 | /* if pid == 0 here, we never forked */
|
---|
1290 |
|
---|
1291 | if (pid > 0) { /* parent */
|
---|
1292 | if (sep->se_wait) {
|
---|
1293 | /* tcp wait: we passed listening socket to child,
|
---|
1294 | * will wait for child to terminate */
|
---|
1295 | sep->se_wait = pid;
|
---|
1296 | remove_fd_from_set(sep->se_fd);
|
---|
1297 | }
|
---|
1298 | if (new_udp_fd >= 0) {
|
---|
1299 | /* udp nowait: child connected the socket,
|
---|
1300 | * we created and will use new, unconnected one */
|
---|
1301 | xmove_fd(new_udp_fd, sep->se_fd);
|
---|
1302 | }
|
---|
1303 | restore_sigmask(&omask);
|
---|
1304 | maybe_close(accepted_fd);
|
---|
1305 | continue; /* -> check next fd in fd set */
|
---|
1306 | }
|
---|
1307 |
|
---|
1308 | /* we are either child or didn't vfork at all */
|
---|
1309 | #ifdef INETD_BUILTINS_ENABLED
|
---|
1310 | if (sep->se_builtin) {
|
---|
1311 | if (pid) { /* "pid" is -1: we did vfork */
|
---|
1312 | close(sep->se_fd); /* listening socket */
|
---|
1313 | logmode = LOGMODE_NONE; /* make xwrite etc silent */
|
---|
1314 | }
|
---|
1315 | restore_sigmask(&omask);
|
---|
1316 | if (sep->se_socktype == SOCK_STREAM)
|
---|
1317 | sep->se_builtin->bi_stream_fn(ctrl, sep);
|
---|
1318 | else
|
---|
1319 | sep->se_builtin->bi_dgram_fn(ctrl, sep);
|
---|
1320 | if (pid) /* we did vfork */
|
---|
1321 | _exit(EXIT_FAILURE);
|
---|
1322 | maybe_close(accepted_fd);
|
---|
1323 | continue; /* -> check next fd in fd set */
|
---|
1324 | }
|
---|
1325 | #endif
|
---|
1326 | /* child */
|
---|
1327 | setsid();
|
---|
1328 | /* "nowait" udp */
|
---|
1329 | if (new_udp_fd >= 0) {
|
---|
1330 | len_and_sockaddr *lsa = xzalloc_lsa(sep->se_family);
|
---|
1331 | /* peek at the packet and remember peer addr */
|
---|
1332 | int r = recvfrom(ctrl, NULL, 0, MSG_PEEK|MSG_DONTWAIT,
|
---|
1333 | &lsa->u.sa, &lsa->len);
|
---|
1334 | if (r < 0)
|
---|
1335 | goto do_exit1;
|
---|
1336 | /* make this socket "connected" to peer addr:
|
---|
1337 | * only packets from this peer will be recv'ed,
|
---|
1338 | * and bare write()/send() will work on it */
|
---|
1339 | connect(ctrl, &lsa->u.sa, lsa->len);
|
---|
1340 | free(lsa);
|
---|
1341 | }
|
---|
1342 | /* prepare env and exec program */
|
---|
1343 | pwd = getpwnam(sep->se_user);
|
---|
1344 | if (pwd == NULL) {
|
---|
1345 | bb_error_msg("%s: no such %s", sep->se_user, "user");
|
---|
1346 | goto do_exit1;
|
---|
1347 | }
|
---|
1348 | if (sep->se_group && (grp = getgrnam(sep->se_group)) == NULL) {
|
---|
1349 | bb_error_msg("%s: no such %s", sep->se_group, "group");
|
---|
1350 | goto do_exit1;
|
---|
1351 | }
|
---|
1352 | if (real_uid != 0 && real_uid != pwd->pw_uid) {
|
---|
1353 | /* a user running private inetd */
|
---|
1354 | bb_error_msg("non-root must run services as himself");
|
---|
1355 | goto do_exit1;
|
---|
1356 | }
|
---|
1357 | if (pwd->pw_uid) {
|
---|
1358 | if (sep->se_group)
|
---|
1359 | pwd->pw_gid = grp->gr_gid;
|
---|
1360 | /* initgroups, setgid, setuid: */
|
---|
1361 | change_identity(pwd);
|
---|
1362 | } else if (sep->se_group) {
|
---|
1363 | xsetgid(grp->gr_gid);
|
---|
1364 | setgroups(1, &grp->gr_gid);
|
---|
1365 | }
|
---|
1366 | if (rlim_ofile.rlim_cur != rlim_ofile_cur)
|
---|
1367 | if (setrlimit(RLIMIT_NOFILE, &rlim_ofile) < 0)
|
---|
1368 | bb_perror_msg("setrlimit");
|
---|
1369 |
|
---|
1370 | /* closelog(); - WRONG. we are after vfork,
|
---|
1371 | * this may confuse syslog() internal state.
|
---|
1372 | * Let's hope libc sets syslog fd to CLOEXEC...
|
---|
1373 | */
|
---|
1374 | xmove_fd(ctrl, STDIN_FILENO);
|
---|
1375 | xdup2(STDIN_FILENO, STDOUT_FILENO);
|
---|
1376 | /* manpages of inetd I managed to find either say
|
---|
1377 | * that stderr is also redirected to the network,
|
---|
1378 | * or do not talk about redirection at all (!) */
|
---|
1379 | if (!sep->se_wait) /* only for usual "tcp nowait" */
|
---|
1380 | xdup2(STDIN_FILENO, STDERR_FILENO);
|
---|
1381 | /* NB: among others, this loop closes listening sockets
|
---|
1382 | * for nowait stream children */
|
---|
1383 | for (sep2 = serv_list; sep2; sep2 = sep2->se_next)
|
---|
1384 | if (sep2->se_fd != ctrl)
|
---|
1385 | maybe_close(sep2->se_fd);
|
---|
1386 | sigaction_set(SIGPIPE, &saved_pipe_handler);
|
---|
1387 | restore_sigmask(&omask);
|
---|
1388 | BB_EXECVP(sep->se_program, sep->se_argv);
|
---|
1389 | bb_perror_msg("can't execute '%s'", sep->se_program);
|
---|
1390 | do_exit1:
|
---|
1391 | /* eat packet in udp case */
|
---|
1392 | if (sep->se_socktype != SOCK_STREAM)
|
---|
1393 | recv(0, line, LINE_SIZE, MSG_DONTWAIT);
|
---|
1394 | _exit(EXIT_FAILURE);
|
---|
1395 | } /* for (sep = servtab...) */
|
---|
1396 | } /* for (;;) */
|
---|
1397 | }
|
---|
1398 |
|
---|
1399 | #if !BB_MMU
|
---|
1400 | static const char *const cat_args[] = { "cat", NULL };
|
---|
1401 | #endif
|
---|
1402 |
|
---|
1403 | /*
|
---|
1404 | * Internet services provided internally by inetd:
|
---|
1405 | */
|
---|
1406 | #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_ECHO
|
---|
1407 | /* Echo service -- echo data back. */
|
---|
1408 | /* ARGSUSED */
|
---|
1409 | static void FAST_FUNC echo_stream(int s, servtab_t *sep UNUSED_PARAM)
|
---|
1410 | {
|
---|
1411 | #if BB_MMU
|
---|
1412 | while (1) {
|
---|
1413 | ssize_t sz = safe_read(s, line, LINE_SIZE);
|
---|
1414 | if (sz <= 0)
|
---|
1415 | break;
|
---|
1416 | xwrite(s, line, sz);
|
---|
1417 | }
|
---|
1418 | #else
|
---|
1419 | /* We are after vfork here! */
|
---|
1420 | /* move network socket to stdin/stdout */
|
---|
1421 | xmove_fd(s, STDIN_FILENO);
|
---|
1422 | xdup2(STDIN_FILENO, STDOUT_FILENO);
|
---|
1423 | /* no error messages please... */
|
---|
1424 | close(STDERR_FILENO);
|
---|
1425 | xopen(bb_dev_null, O_WRONLY);
|
---|
1426 | BB_EXECVP("cat", (char**)cat_args);
|
---|
1427 | /* on failure we return to main, which does exit(EXIT_FAILURE) */
|
---|
1428 | #endif
|
---|
1429 | }
|
---|
1430 | static void FAST_FUNC echo_dg(int s, servtab_t *sep)
|
---|
1431 | {
|
---|
1432 | enum { BUFSIZE = 12*1024 }; /* for jumbo sized packets! :) */
|
---|
1433 | char *buf = xmalloc(BUFSIZE); /* too big for stack */
|
---|
1434 | int sz;
|
---|
1435 | len_and_sockaddr *lsa = alloca(LSA_LEN_SIZE + sep->se_lsa->len);
|
---|
1436 |
|
---|
1437 | lsa->len = sep->se_lsa->len;
|
---|
1438 | /* dgram builtins are non-forking - DONT BLOCK! */
|
---|
1439 | sz = recvfrom(s, buf, BUFSIZE, MSG_DONTWAIT, &lsa->u.sa, &lsa->len);
|
---|
1440 | if (sz > 0)
|
---|
1441 | sendto(s, buf, sz, 0, &lsa->u.sa, lsa->len);
|
---|
1442 | free(buf);
|
---|
1443 | }
|
---|
1444 | #endif /* FEATURE_INETD_SUPPORT_BUILTIN_ECHO */
|
---|
1445 |
|
---|
1446 |
|
---|
1447 | #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DISCARD
|
---|
1448 | /* Discard service -- ignore data. */
|
---|
1449 | /* ARGSUSED */
|
---|
1450 | static void FAST_FUNC discard_stream(int s, servtab_t *sep UNUSED_PARAM)
|
---|
1451 | {
|
---|
1452 | #if BB_MMU
|
---|
1453 | while (safe_read(s, line, LINE_SIZE) > 0)
|
---|
1454 | continue;
|
---|
1455 | #else
|
---|
1456 | /* We are after vfork here! */
|
---|
1457 | /* move network socket to stdin */
|
---|
1458 | xmove_fd(s, STDIN_FILENO);
|
---|
1459 | /* discard output */
|
---|
1460 | close(STDOUT_FILENO);
|
---|
1461 | xopen(bb_dev_null, O_WRONLY);
|
---|
1462 | /* no error messages please... */
|
---|
1463 | xdup2(STDOUT_FILENO, STDERR_FILENO);
|
---|
1464 | BB_EXECVP("cat", (char**)cat_args);
|
---|
1465 | /* on failure we return to main, which does exit(EXIT_FAILURE) */
|
---|
1466 | #endif
|
---|
1467 | }
|
---|
1468 | /* ARGSUSED */
|
---|
1469 | static void FAST_FUNC discard_dg(int s, servtab_t *sep UNUSED_PARAM)
|
---|
1470 | {
|
---|
1471 | /* dgram builtins are non-forking - DONT BLOCK! */
|
---|
1472 | recv(s, line, LINE_SIZE, MSG_DONTWAIT);
|
---|
1473 | }
|
---|
1474 | #endif /* FEATURE_INETD_SUPPORT_BUILTIN_DISCARD */
|
---|
1475 |
|
---|
1476 |
|
---|
1477 | #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_CHARGEN
|
---|
1478 | #define LINESIZ 72
|
---|
1479 | static void init_ring(void)
|
---|
1480 | {
|
---|
1481 | int i;
|
---|
1482 |
|
---|
1483 | end_ring = ring;
|
---|
1484 | for (i = ' '; i < 127; i++)
|
---|
1485 | *end_ring++ = i;
|
---|
1486 | }
|
---|
1487 | /* Character generator. MMU arches only. */
|
---|
1488 | /* ARGSUSED */
|
---|
1489 | static void FAST_FUNC chargen_stream(int s, servtab_t *sep UNUSED_PARAM)
|
---|
1490 | {
|
---|
1491 | char *rs;
|
---|
1492 | int len;
|
---|
1493 | char text[LINESIZ + 2];
|
---|
1494 |
|
---|
1495 | if (!end_ring) {
|
---|
1496 | init_ring();
|
---|
1497 | rs = ring;
|
---|
1498 | }
|
---|
1499 |
|
---|
1500 | text[LINESIZ] = '\r';
|
---|
1501 | text[LINESIZ + 1] = '\n';
|
---|
1502 | rs = ring;
|
---|
1503 | for (;;) {
|
---|
1504 | len = end_ring - rs;
|
---|
1505 | if (len >= LINESIZ)
|
---|
1506 | memmove(text, rs, LINESIZ);
|
---|
1507 | else {
|
---|
1508 | memmove(text, rs, len);
|
---|
1509 | memmove(text + len, ring, LINESIZ - len);
|
---|
1510 | }
|
---|
1511 | if (++rs == end_ring)
|
---|
1512 | rs = ring;
|
---|
1513 | xwrite(s, text, sizeof(text));
|
---|
1514 | }
|
---|
1515 | }
|
---|
1516 | /* ARGSUSED */
|
---|
1517 | static void FAST_FUNC chargen_dg(int s, servtab_t *sep)
|
---|
1518 | {
|
---|
1519 | int len;
|
---|
1520 | char text[LINESIZ + 2];
|
---|
1521 | len_and_sockaddr *lsa = alloca(LSA_LEN_SIZE + sep->se_lsa->len);
|
---|
1522 |
|
---|
1523 | /* Eat UDP packet which started it all */
|
---|
1524 | /* dgram builtins are non-forking - DONT BLOCK! */
|
---|
1525 | lsa->len = sep->se_lsa->len;
|
---|
1526 | if (recvfrom(s, text, sizeof(text), MSG_DONTWAIT, &lsa->u.sa, &lsa->len) < 0)
|
---|
1527 | return;
|
---|
1528 |
|
---|
1529 | if (!end_ring) {
|
---|
1530 | init_ring();
|
---|
1531 | ring_pos = ring;
|
---|
1532 | }
|
---|
1533 |
|
---|
1534 | len = end_ring - ring_pos;
|
---|
1535 | if (len >= LINESIZ)
|
---|
1536 | memmove(text, ring_pos, LINESIZ);
|
---|
1537 | else {
|
---|
1538 | memmove(text, ring_pos, len);
|
---|
1539 | memmove(text + len, ring, LINESIZ - len);
|
---|
1540 | }
|
---|
1541 | if (++ring_pos == end_ring)
|
---|
1542 | ring_pos = ring;
|
---|
1543 | text[LINESIZ] = '\r';
|
---|
1544 | text[LINESIZ + 1] = '\n';
|
---|
1545 | sendto(s, text, sizeof(text), 0, &lsa->u.sa, lsa->len);
|
---|
1546 | }
|
---|
1547 | #endif /* FEATURE_INETD_SUPPORT_BUILTIN_CHARGEN */
|
---|
1548 |
|
---|
1549 |
|
---|
1550 | #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_TIME
|
---|
1551 | /*
|
---|
1552 | * Return a machine readable date and time, in the form of the
|
---|
1553 | * number of seconds since midnight, Jan 1, 1900. Since gettimeofday
|
---|
1554 | * returns the number of seconds since midnight, Jan 1, 1970,
|
---|
1555 | * we must add 2208988800 seconds to this figure to make up for
|
---|
1556 | * some seventy years Bell Labs was asleep.
|
---|
1557 | */
|
---|
1558 | static uint32_t machtime(void)
|
---|
1559 | {
|
---|
1560 | struct timeval tv;
|
---|
1561 |
|
---|
1562 | gettimeofday(&tv, NULL);
|
---|
1563 | return htonl((uint32_t)(tv.tv_sec + 2208988800));
|
---|
1564 | }
|
---|
1565 | /* ARGSUSED */
|
---|
1566 | static void FAST_FUNC machtime_stream(int s, servtab_t *sep UNUSED_PARAM)
|
---|
1567 | {
|
---|
1568 | uint32_t result;
|
---|
1569 |
|
---|
1570 | result = machtime();
|
---|
1571 | full_write(s, &result, sizeof(result));
|
---|
1572 | }
|
---|
1573 | static void FAST_FUNC machtime_dg(int s, servtab_t *sep)
|
---|
1574 | {
|
---|
1575 | uint32_t result;
|
---|
1576 | len_and_sockaddr *lsa = alloca(LSA_LEN_SIZE + sep->se_lsa->len);
|
---|
1577 |
|
---|
1578 | lsa->len = sep->se_lsa->len;
|
---|
1579 | if (recvfrom(s, line, LINE_SIZE, MSG_DONTWAIT, &lsa->u.sa, &lsa->len) < 0)
|
---|
1580 | return;
|
---|
1581 |
|
---|
1582 | result = machtime();
|
---|
1583 | sendto(s, &result, sizeof(result), 0, &lsa->u.sa, lsa->len);
|
---|
1584 | }
|
---|
1585 | #endif /* FEATURE_INETD_SUPPORT_BUILTIN_TIME */
|
---|
1586 |
|
---|
1587 |
|
---|
1588 | #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DAYTIME
|
---|
1589 | /* Return human-readable time of day */
|
---|
1590 | /* ARGSUSED */
|
---|
1591 | static void FAST_FUNC daytime_stream(int s, servtab_t *sep UNUSED_PARAM)
|
---|
1592 | {
|
---|
1593 | time_t t;
|
---|
1594 |
|
---|
1595 | t = time(NULL);
|
---|
1596 | fdprintf(s, "%.24s\r\n", ctime(&t));
|
---|
1597 | }
|
---|
1598 | static void FAST_FUNC daytime_dg(int s, servtab_t *sep)
|
---|
1599 | {
|
---|
1600 | time_t t;
|
---|
1601 | len_and_sockaddr *lsa = alloca(LSA_LEN_SIZE + sep->se_lsa->len);
|
---|
1602 |
|
---|
1603 | lsa->len = sep->se_lsa->len;
|
---|
1604 | if (recvfrom(s, line, LINE_SIZE, MSG_DONTWAIT, &lsa->u.sa, &lsa->len) < 0)
|
---|
1605 | return;
|
---|
1606 |
|
---|
1607 | t = time(NULL);
|
---|
1608 | sprintf(line, "%.24s\r\n", ctime(&t));
|
---|
1609 | sendto(s, line, strlen(line), 0, &lsa->u.sa, lsa->len);
|
---|
1610 | }
|
---|
1611 | #endif /* FEATURE_INETD_SUPPORT_BUILTIN_DAYTIME */
|
---|