inetd.c revision 1.38.2.3
1 /* $NetBSD: inetd.c,v 1.38.2.3 1998/09/27 23:36:23 cgd Exp $ */ 2 3 /* 4 * Copyright (c) 1983, 1991, 1993, 1994 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by the University of 18 * California, Berkeley and its contributors. 19 * 4. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 */ 35 36 #include <sys/cdefs.h> 37 #ifndef lint 38 __COPYRIGHT("@(#) Copyright (c) 1983, 1991, 1993, 1994\n\ 39 The Regents of the University of California. All rights reserved.\n"); 40 #if 0 41 static char sccsid[] = "@(#)inetd.c 8.4 (Berkeley) 4/13/94"; 42 #else 43 __RCSID("$NetBSD: inetd.c,v 1.38.2.3 1998/09/27 23:36:23 cgd Exp $"); 44 #endif 45 #endif /* not lint */ 46 47 /* 48 * Inetd - Internet super-server 49 * 50 * This program invokes all internet services as needed. Connection-oriented 51 * services are invoked each time a connection is made, by creating a process. 52 * This process is passed the connection as file descriptor 0 and is expected 53 * to do a getpeername to find out the source host and port. 54 * 55 * Datagram oriented services are invoked when a datagram 56 * arrives; a process is created and passed a pending message 57 * on file descriptor 0. Datagram servers may either connect 58 * to their peer, freeing up the original socket for inetd 59 * to receive further messages on, or ``take over the socket'', 60 * processing all arriving datagrams and, eventually, timing 61 * out. The first type of server is said to be ``multi-threaded''; 62 * the second type of server ``single-threaded''. 63 * 64 * Inetd uses a configuration file which is read at startup 65 * and, possibly, at some later time in response to a hangup signal. 66 * The configuration file is ``free format'' with fields given in the 67 * order shown below. Continuation lines for an entry must being with 68 * a space or tab. All fields must be present in each entry. 69 * 70 * service name must be in /etc/services or must 71 * name a tcpmux service 72 * socket type stream/dgram/raw/rdm/seqpacket 73 * protocol must be in /etc/protocols 74 * wait/nowait[.max] single-threaded/multi-threaded, max # 75 * user[.group] user/group to run daemon as 76 * server program full path name 77 * server program arguments maximum of MAXARGS (20) 78 * 79 * For RPC services 80 * service name/version must be in /etc/rpc 81 * socket type stream/dgram/raw/rdm/seqpacket 82 * protocol must be in /etc/protocols 83 * wait/nowait[.max] single-threaded/multi-threaded 84 * user[.group] user to run daemon as 85 * server program full path name 86 * server program arguments maximum of MAXARGS (20) 87 * 88 * For non-RPC services, the "service name" can be of the form 89 * hostaddress:servicename, in which case the hostaddress is used 90 * as the host portion of the address to listen on. If hostaddress 91 * consists of a single `*' character, INADDR_ANY is used. 92 * 93 * A line can also consist of just 94 * hostaddress: 95 * where hostaddress is as in the preceding paragraph. Such a line must 96 * have no further fields; the specified hostaddress is remembered and 97 * used for all further lines that have no hostaddress specified, 98 * until the next such line (or EOF). (This is why * is provided to 99 * allow explicit specification of INADDR_ANY.) A line 100 * *: 101 * is implicitly in effect at the beginning of the file. 102 * 103 * The hostaddress specifier may (and often will) contain dots; 104 * the service name must not. 105 * 106 * For RPC services, host-address specifiers are accepted and will 107 * work to some extent; however, because of limitations in the 108 * portmapper interface, it will not work to try to give more than 109 * one line for any given RPC service, even if the host-address 110 * specifiers are different. 111 * 112 * TCP services without official port numbers are handled with the 113 * RFC1078-based tcpmux internal service. Tcpmux listens on port 1 for 114 * requests. When a connection is made from a foreign host, the service 115 * requested is passed to tcpmux, which looks it up in the servtab list 116 * and returns the proper entry for the service. Tcpmux returns a 117 * negative reply if the service doesn't exist, otherwise the invoked 118 * server is expected to return the positive reply if the service type in 119 * inetd.conf file has the prefix "tcpmux/". If the service type has the 120 * prefix "tcpmux/+", tcpmux will return the positive reply for the 121 * process; this is for compatibility with older server code, and also 122 * allows you to invoke programs that use stdin/stdout without putting any 123 * special server code in them. Services that use tcpmux are "nowait" 124 * because they do not have a well-known port and hence cannot listen 125 * for new requests. 126 * 127 * Comment lines are indicated by a `#' in column 1. 128 */ 129 130 /* 131 * Here's the scoop concerning the user.group feature: 132 * 133 * 1) set-group-option off. 134 * 135 * a) user = root: NO setuid() or setgid() is done 136 * 137 * b) other: setuid() 138 * setgid(primary group as found in passwd) 139 * initgroups(name, primary group) 140 * 141 * 2) set-group-option on. 142 * 143 * a) user = root: NO setuid() 144 * setgid(specified group) 145 * NO initgroups() 146 * 147 * b) other: setuid() 148 * setgid(specified group) 149 * initgroups(name, specified group) 150 * 151 */ 152 153 #include <sys/param.h> 154 #include <sys/stat.h> 155 #include <sys/ioctl.h> 156 #include <sys/socket.h> 157 #include <sys/un.h> 158 #include <sys/wait.h> 159 #include <sys/time.h> 160 #include <sys/resource.h> 161 162 #ifndef RLIMIT_NOFILE 163 #define RLIMIT_NOFILE RLIMIT_OFILE 164 #endif 165 166 #define RPC 167 168 #include <netinet/in.h> 169 #include <arpa/inet.h> 170 #ifdef RPC 171 #include <rpc/rpc.h> 172 #include <rpc/pmap_clnt.h> 173 #endif 174 175 #include <errno.h> 176 #include <fcntl.h> 177 #include <grp.h> 178 #include <netdb.h> 179 #include <pwd.h> 180 #include <signal.h> 181 #include <stdio.h> 182 #include <stdlib.h> 183 #include <string.h> 184 #include <syslog.h> 185 #include <unistd.h> 186 187 #include "pathnames.h" 188 189 #ifdef LIBWRAP 190 # include <tcpd.h> 191 #ifndef LIBWRAP_ALLOW_FACILITY 192 # define LIBWRAP_ALLOW_FACILITY LOG_AUTH 193 #endif 194 #ifndef LIBWRAP_ALLOW_SEVERITY 195 # define LIBWRAP_ALLOW_SEVERITY LOG_INFO 196 #endif 197 #ifndef LIBWRAP_DENY_FACILITY 198 # define LIBWRAP_DENY_FACILITY LOG_AUTH 199 #endif 200 #ifndef LIBWRAP_DENY_SEVERITY 201 # define LIBWRAP_DENY_SEVERITY LOG_WARNING 202 #endif 203 int allow_severity = LIBWRAP_ALLOW_FACILITY|LIBWRAP_ALLOW_SEVERITY; 204 int deny_severity = LIBWRAP_DENY_FACILITY|LIBWRAP_DENY_SEVERITY; 205 #endif 206 207 #define TOOMANY 40 /* don't start more than TOOMANY */ 208 #define CNT_INTVL 60 /* servers in CNT_INTVL sec. */ 209 #define RETRYTIME (60*10) /* retry after bind or server fail */ 210 211 #define SIGBLOCK (sigmask(SIGCHLD)|sigmask(SIGHUP)|sigmask(SIGALRM)) 212 213 int debug; 214 #ifdef LIBWRAP 215 int lflag; 216 #endif 217 int nsock, maxsock; 218 fd_set allsock; 219 int options; 220 int timingout; 221 struct servent *sp; 222 char *curdom; 223 224 #ifndef OPEN_MAX 225 #define OPEN_MAX 64 226 #endif 227 228 /* Reserve some descriptors, 3 stdio + at least: 1 log, 1 conf. file */ 229 #define FD_MARGIN (8) 230 typeof(((struct rlimit *)0)->rlim_cur) rlim_ofile_cur = OPEN_MAX; 231 232 #ifdef RLIMIT_NOFILE 233 struct rlimit rlim_ofile; 234 #endif 235 236 struct servtab { 237 char *se_hostaddr; /* host address to listen on */ 238 char *se_service; /* name of service */ 239 int se_socktype; /* type of socket to use */ 240 int se_family; /* address family */ 241 char *se_proto; /* protocol used */ 242 int se_rpcprog; /* rpc program number */ 243 int se_rpcversl; /* rpc program lowest version */ 244 int se_rpcversh; /* rpc program highest version */ 245 #define isrpcservice(sep) ((sep)->se_rpcversl != 0) 246 short se_wait; /* single threaded server */ 247 short se_checked; /* looked at during merge */ 248 char *se_user; /* user name to run as */ 249 char *se_group; /* group name to run as */ 250 struct biltin *se_bi; /* if built-in, description */ 251 char *se_server; /* server program */ 252 #define MAXARGV 20 253 char *se_argv[MAXARGV+1]; /* program arguments */ 254 int se_fd; /* open descriptor */ 255 int se_type; /* type */ 256 union { 257 struct sockaddr se_un_ctrladdr; 258 struct sockaddr_in se_un_ctrladdr_in; 259 struct sockaddr_un se_un_ctrladdr_un; 260 } se_un; /* bound address */ 261 #define se_ctrladdr se_un.se_un_ctrladdr 262 #define se_ctrladdr_in se_un.se_un_ctrladdr_in 263 #define se_ctrladdr_un se_un.se_un_ctrladdr_un 264 int se_ctrladdr_size; 265 int se_max; /* max # of instances of this service */ 266 int se_count; /* number started since se_time */ 267 struct timeval se_time; /* start of se_count */ 268 #ifdef MULOG 269 int se_log; 270 #define MULOG_RFC931 0x40000000 271 #endif 272 struct servtab *se_next; 273 } *servtab; 274 275 #define NORM_TYPE 0 276 #define MUX_TYPE 1 277 #define MUXPLUS_TYPE 2 278 #define ISMUX(sep) (((sep)->se_type == MUX_TYPE) || \ 279 ((sep)->se_type == MUXPLUS_TYPE)) 280 #define ISMUXPLUS(sep) ((sep)->se_type == MUXPLUS_TYPE) 281 282 283 void chargen_dg __P((int, struct servtab *)); 284 void chargen_stream __P((int, struct servtab *)); 285 void close_sep __P((struct servtab *)); 286 void config __P((int)); 287 void daytime_dg __P((int, struct servtab *)); 288 void daytime_stream __P((int, struct servtab *)); 289 void discard_dg __P((int, struct servtab *)); 290 void discard_stream __P((int, struct servtab *)); 291 void echo_dg __P((int, struct servtab *)); 292 void echo_stream __P((int, struct servtab *)); 293 void endconfig __P((void)); 294 struct servtab *enter __P((struct servtab *)); 295 void freeconfig __P((struct servtab *)); 296 struct servtab *getconfigent __P((void)); 297 void goaway __P((int)); 298 void machtime_dg __P((int, struct servtab *)); 299 void machtime_stream __P((int, struct servtab *)); 300 char *newstr __P((char *)); 301 char *nextline __P((FILE *)); 302 void print_service __P((char *, struct servtab *)); 303 void reapchild __P((int)); 304 void retry __P((int)); 305 void run_service __P((int, struct servtab *)); 306 int setconfig __P((void)); 307 void setup __P((struct servtab *)); 308 char *sskip __P((char **)); 309 char *skip __P((char **)); 310 void tcpmux __P((int, struct servtab *)); 311 void usage __P((void)); 312 void logpid __P((void)); 313 void register_rpc __P((struct servtab *sep)); 314 void unregister_rpc __P((struct servtab *sep)); 315 void bump_nofile __P((void)); 316 void inetd_setproctitle __P((char *, int)); 317 void initring __P((void)); 318 long machtime __P((void)); 319 static int getline __P((int, char *, int)); 320 int main __P((int, char *[], char *[])); 321 322 struct biltin { 323 char *bi_service; /* internally provided service name */ 324 int bi_socktype; /* type of socket supported */ 325 short bi_fork; /* 1 if should fork before call */ 326 short bi_wait; /* 1 if should wait for child */ 327 void (*bi_fn) __P((int, struct servtab *)); 328 /* function which performs it */ 329 } biltins[] = { 330 /* Echo received data */ 331 { "echo", SOCK_STREAM, 1, 0, echo_stream }, 332 { "echo", SOCK_DGRAM, 0, 0, echo_dg }, 333 334 /* Internet /dev/null */ 335 { "discard", SOCK_STREAM, 1, 0, discard_stream }, 336 { "discard", SOCK_DGRAM, 0, 0, discard_dg }, 337 338 /* Return 32 bit time since 1970 */ 339 { "time", SOCK_STREAM, 0, 0, machtime_stream }, 340 { "time", SOCK_DGRAM, 0, 0, machtime_dg }, 341 342 /* Return human-readable time */ 343 { "daytime", SOCK_STREAM, 0, 0, daytime_stream }, 344 { "daytime", SOCK_DGRAM, 0, 0, daytime_dg }, 345 346 /* Familiar character generator */ 347 { "chargen", SOCK_STREAM, 1, 0, chargen_stream }, 348 { "chargen", SOCK_DGRAM, 0, 0, chargen_dg }, 349 350 { "tcpmux", SOCK_STREAM, 1, 0, tcpmux }, 351 352 { NULL } 353 }; 354 355 #define NUMINT (sizeof(intab) / sizeof(struct inent)) 356 char *CONFIG = _PATH_INETDCONF; 357 char **Argv; 358 char *LastArg; 359 extern char *__progname; 360 361 #ifdef sun 362 /* 363 * Sun's RPC library caches the result of `dtablesize()' 364 * This is incompatible with our "bumping" of file descriptors "on demand" 365 */ 366 int 367 _rpc_dtablesize() 368 { 369 return rlim_ofile_cur; 370 } 371 #endif 372 373 int 374 main(argc, argv, envp) 375 int argc; 376 char *argv[], *envp[]; 377 { 378 struct servtab *sep, *nsep; 379 struct sigvec sv; 380 int ch, dofork; 381 pid_t pid; 382 383 Argv = argv; 384 if (envp == 0 || *envp == 0) 385 envp = argv; 386 while (*envp) 387 envp++; 388 LastArg = envp[-1] + strlen(envp[-1]); 389 390 while ((ch = getopt(argc, argv, 391 #ifdef LIBWRAP 392 "dl" 393 #else 394 "d" 395 #endif 396 )) != -1) 397 switch(ch) { 398 case 'd': 399 debug = 1; 400 options |= SO_DEBUG; 401 break; 402 #ifdef LIBWRAP 403 case 'l': 404 lflag = 1; 405 break; 406 #endif 407 case '?': 408 default: 409 usage(); 410 } 411 argc -= optind; 412 argv += optind; 413 414 if (argc > 0) 415 CONFIG = argv[0]; 416 417 if (debug == 0) 418 daemon(0, 0); 419 openlog(__progname, LOG_PID | LOG_NOWAIT, LOG_DAEMON); 420 logpid(); 421 422 #ifdef RLIMIT_NOFILE 423 if (getrlimit(RLIMIT_NOFILE, &rlim_ofile) < 0) { 424 syslog(LOG_ERR, "getrlimit: %m"); 425 } else { 426 rlim_ofile_cur = rlim_ofile.rlim_cur; 427 if (rlim_ofile_cur == RLIM_INFINITY) /* ! */ 428 rlim_ofile_cur = OPEN_MAX; 429 } 430 #endif 431 432 memset(&sv, 0, sizeof(sv)); 433 sv.sv_mask = SIGBLOCK; 434 sv.sv_handler = retry; 435 sigvec(SIGALRM, &sv, (struct sigvec *)0); 436 config(SIGHUP); 437 sv.sv_handler = config; 438 sigvec(SIGHUP, &sv, (struct sigvec *)0); 439 sv.sv_handler = reapchild; 440 sigvec(SIGCHLD, &sv, (struct sigvec *)0); 441 sv.sv_handler = goaway; 442 sigvec(SIGTERM, &sv, (struct sigvec *)0); 443 sv.sv_handler = goaway; 444 sigvec(SIGINT, &sv, (struct sigvec *)0); 445 sv.sv_mask = 0L; 446 sv.sv_handler = SIG_IGN; 447 sigvec(SIGPIPE, &sv, (struct sigvec *)0); 448 449 { 450 /* space for daemons to overwrite environment for ps */ 451 #define DUMMYSIZE 100 452 char dummy[DUMMYSIZE]; 453 454 (void)memset(dummy, 'x', DUMMYSIZE - 1); 455 dummy[DUMMYSIZE - 1] = '\0'; 456 457 (void)setenv("inetd_dummy", dummy, 1); 458 } 459 460 for (;;) { 461 int n, ctrl; 462 fd_set readable; 463 464 if (nsock == 0) { 465 (void) sigblock(SIGBLOCK); 466 while (nsock == 0) 467 sigpause(0L); 468 (void) sigsetmask(0L); 469 } 470 readable = allsock; 471 if ((n = select(maxsock + 1, &readable, (fd_set *)0, 472 (fd_set *)0, (struct timeval *)0)) <= 0) { 473 if (n == -1 && errno != EINTR) { 474 syslog(LOG_WARNING, "select: %m"); 475 sleep(1); 476 } 477 continue; 478 } 479 for (sep = servtab; n && sep; sep = nsep) { 480 nsep = sep->se_next; 481 if (sep->se_fd != -1 && FD_ISSET(sep->se_fd, &readable)) { 482 n--; 483 if (debug) 484 fprintf(stderr, "someone wants %s\n", sep->se_service); 485 if (!sep->se_wait && sep->se_socktype == SOCK_STREAM) { 486 /* XXX here do the libwrap check-before-accept */ 487 ctrl = accept(sep->se_fd, (struct sockaddr *)0, 488 (int *)0); 489 if (debug) 490 fprintf(stderr, "accept, ctrl %d\n", ctrl); 491 if (ctrl < 0) { 492 if (errno != EINTR) 493 syslog(LOG_WARNING, 494 "accept (for %s): %m", 495 sep->se_service); 496 continue; 497 } 498 } else 499 ctrl = sep->se_fd; 500 (void) sigblock(SIGBLOCK); 501 pid = 0; 502 #ifdef LIBWRAP_INTERNAL 503 dofork = 1; 504 #else 505 dofork = (sep->se_bi == 0 || sep->se_bi->bi_fork); 506 #endif 507 if (dofork) { 508 if (sep->se_count++ == 0) 509 (void)gettimeofday(&sep->se_time, 510 (struct timezone *)0); 511 else if (sep->se_count >= sep->se_max) { 512 struct timeval now; 513 514 (void)gettimeofday(&now, (struct timezone *)0); 515 if (now.tv_sec - sep->se_time.tv_sec > 516 CNT_INTVL) { 517 sep->se_time = now; 518 sep->se_count = 1; 519 } else { 520 syslog(LOG_ERR, 521 "%s/%s server failing (looping), service terminated\n", 522 sep->se_service, sep->se_proto); 523 if (!sep->se_wait && sep->se_socktype == SOCK_STREAM) 524 close(ctrl); 525 close_sep(sep); 526 sigsetmask(0L); 527 if (!timingout) { 528 timingout = 1; 529 alarm(RETRYTIME); 530 } 531 continue; 532 } 533 } 534 pid = fork(); 535 if (pid < 0) { 536 syslog(LOG_ERR, "fork: %m"); 537 if (!sep->se_wait && sep->se_socktype == SOCK_STREAM) 538 close(ctrl); 539 sigsetmask(0L); 540 sleep(1); 541 continue; 542 } 543 if (pid != 0 && sep->se_wait) { 544 sep->se_wait = pid; 545 FD_CLR(sep->se_fd, &allsock); 546 nsock--; 547 } 548 if (pid == 0) { 549 sv.sv_mask = 0L; 550 sv.sv_handler = SIG_DFL; 551 sigvec(SIGPIPE, &sv, (struct sigvec *)0); 552 if (debug) 553 setsid(); 554 } 555 } 556 sigsetmask(0L); 557 if (pid == 0) { 558 run_service(ctrl, sep); 559 if (dofork) 560 exit(0); 561 } 562 if (!sep->se_wait && sep->se_socktype == SOCK_STREAM) 563 close(ctrl); 564 } 565 } 566 } 567 } 568 569 void 570 run_service(ctrl, sep) 571 int ctrl; 572 struct servtab *sep; 573 { 574 struct passwd *pwd; 575 struct group *grp = NULL; /* XXX gcc */ 576 #ifdef LIBWRAP 577 struct request_info req; 578 int denied; 579 char buf[7], *service = NULL; /* XXX gcc */ 580 #endif 581 582 #ifdef LIBWRAP 583 #ifndef LIBWRAP_INTERNAL 584 if (sep->se_bi == 0) 585 #endif 586 if (!sep->se_wait && sep->se_socktype == SOCK_STREAM) { 587 request_init(&req, RQ_DAEMON, sep->se_argv[0] ? 588 sep->se_argv[0] : sep->se_service, RQ_FILE, ctrl, NULL); 589 fromhost(&req); 590 denied = !hosts_access(&req); 591 if (denied || lflag) { 592 sp = getservbyport(sep->se_ctrladdr_in.sin_port, 593 sep->se_proto); 594 if (sp == NULL) { 595 (void)snprintf(buf, sizeof buf, "%d", 596 ntohs(sep->se_ctrladdr_in.sin_port)); 597 service = buf; 598 } else 599 service = sp->s_name; 600 } 601 if (denied) { 602 syslog(deny_severity, 603 "refused connection from %.500s, service %s (%s)", 604 eval_client(&req), service, sep->se_proto); 605 goto reject; 606 } 607 if (lflag) { 608 syslog(allow_severity, 609 "connection from %.500s, service %s (%s)", 610 eval_client(&req), service, sep->se_proto); 611 } 612 } 613 #endif /* LIBWRAP */ 614 615 if (sep->se_bi) { 616 (*sep->se_bi->bi_fn)(ctrl, sep); 617 } else { 618 if ((pwd = getpwnam(sep->se_user)) == NULL) { 619 syslog(LOG_ERR, "%s/%s: %s: No such user", 620 sep->se_service, sep->se_proto, sep->se_user); 621 goto reject; 622 } 623 if (sep->se_group && 624 (grp = getgrnam(sep->se_group)) == NULL) { 625 syslog(LOG_ERR, "%s/%s: %s: No such group", 626 sep->se_service, sep->se_proto, sep->se_group); 627 goto reject; 628 } 629 if (pwd->pw_uid) { 630 if (sep->se_group) 631 pwd->pw_gid = grp->gr_gid; 632 if (setgid(pwd->pw_gid) < 0) { 633 syslog(LOG_ERR, 634 "%s/%s: can't set gid %d: %m", sep->se_service, 635 sep->se_proto, pwd->pw_gid); 636 goto reject; 637 } 638 (void) initgroups(pwd->pw_name, 639 pwd->pw_gid); 640 if (setuid(pwd->pw_uid) < 0) { 641 syslog(LOG_ERR, 642 "%s/%s: can't set uid %d: %m", sep->se_service, 643 sep->se_proto, pwd->pw_uid); 644 goto reject; 645 } 646 } else if (sep->se_group) { 647 (void) setgid((gid_t)grp->gr_gid); 648 } 649 if (debug) 650 fprintf(stderr, "%d execl %s\n", 651 getpid(), sep->se_server); 652 #ifdef MULOG 653 if (sep->se_log) 654 dolog(sep, ctrl); 655 #endif 656 /* Set our control descriptor to not close-on-exec... */ 657 if (fcntl(ctrl, F_SETFD, 0) < 0) 658 syslog(LOG_ERR, "fcntl (F_SETFD, 0): %m"); 659 /* ...and dup it to stdin, stdout, and stderr. */ 660 if (ctrl != 0) { 661 dup2(ctrl, 0); 662 close(ctrl); 663 ctrl = 0; 664 } 665 dup2(0, 1); 666 dup2(0, 2); 667 #ifdef RLIMIT_NOFILE 668 if (rlim_ofile.rlim_cur != rlim_ofile_cur && 669 setrlimit(RLIMIT_NOFILE, &rlim_ofile) < 0) 670 syslog(LOG_ERR, "setrlimit: %m"); 671 #endif 672 execv(sep->se_server, sep->se_argv); 673 syslog(LOG_ERR, "cannot execute %s: %m", sep->se_server); 674 reject: 675 if (sep->se_socktype != SOCK_STREAM) 676 recv(ctrl, buf, sizeof (buf), 0); 677 _exit(1); 678 } 679 } 680 681 void 682 reapchild(signo) 683 int signo; 684 { 685 int status; 686 pid_t pid; 687 struct servtab *sep; 688 689 for (;;) { 690 pid = wait3(&status, WNOHANG, (struct rusage *)0); 691 if (pid <= 0) 692 break; 693 if (debug) 694 fprintf(stderr, "%d reaped, status %#x\n", 695 pid, status); 696 for (sep = servtab; sep; sep = sep->se_next) 697 if (sep->se_wait == pid) { 698 if (WIFEXITED(status) && WEXITSTATUS(status)) 699 syslog(LOG_WARNING, 700 "%s: exit status 0x%x", 701 sep->se_server, WEXITSTATUS(status)); 702 else if (WIFSIGNALED(status)) 703 syslog(LOG_WARNING, 704 "%s: exit signal 0x%x", 705 sep->se_server, WTERMSIG(status)); 706 sep->se_wait = 1; 707 FD_SET(sep->se_fd, &allsock); 708 nsock++; 709 if (debug) 710 fprintf(stderr, "restored %s, fd %d\n", 711 sep->se_service, sep->se_fd); 712 } 713 } 714 } 715 716 void 717 config(signo) 718 int signo; 719 { 720 struct servtab *sep, *cp, **sepp; 721 long omask; 722 int n; 723 724 if (!setconfig()) { 725 syslog(LOG_ERR, "%s: %m", CONFIG); 726 return; 727 } 728 for (sep = servtab; sep; sep = sep->se_next) 729 sep->se_checked = 0; 730 while ((cp = getconfigent())) { 731 for (sep = servtab; sep; sep = sep->se_next) 732 if (strcmp(sep->se_service, cp->se_service) == 0 && 733 strcmp(sep->se_hostaddr, cp->se_hostaddr) == 0 && 734 strcmp(sep->se_proto, cp->se_proto) == 0 && 735 ISMUX(sep) == ISMUX(cp)) 736 break; 737 if (sep != 0) { 738 int i; 739 740 #define SWAP(type, a, b) {type c=(type)a; (type)a=(type)b; (type)b=(type)c;} 741 742 omask = sigblock(SIGBLOCK); 743 /* 744 * sep->se_wait may be holding the pid of a daemon 745 * that we're waiting for. If so, don't overwrite 746 * it unless the config file explicitly says don't 747 * wait. 748 */ 749 if (cp->se_bi == 0 && 750 (sep->se_wait == 1 || cp->se_wait == 0)) 751 sep->se_wait = cp->se_wait; 752 SWAP(char *, sep->se_user, cp->se_user); 753 SWAP(char *, sep->se_group, cp->se_group); 754 SWAP(char *, sep->se_server, cp->se_server); 755 for (i = 0; i < MAXARGV; i++) 756 SWAP(char *, sep->se_argv[i], cp->se_argv[i]); 757 SWAP(int, cp->se_type, sep->se_type); 758 SWAP(int, cp->se_max, sep->se_max); 759 #undef SWAP 760 if (isrpcservice(sep)) 761 unregister_rpc(sep); 762 sep->se_rpcversl = cp->se_rpcversl; 763 sep->se_rpcversh = cp->se_rpcversh; 764 sigsetmask(omask); 765 freeconfig(cp); 766 if (debug) 767 print_service("REDO", sep); 768 } else { 769 sep = enter(cp); 770 if (debug) 771 print_service("ADD ", sep); 772 } 773 sep->se_checked = 1; 774 775 switch (sep->se_family) { 776 case AF_UNIX: 777 if (sep->se_fd != -1) 778 break; 779 n = strlen(sep->se_service); 780 if (n > sizeof(sep->se_ctrladdr_un.sun_path)) { 781 syslog(LOG_ERR, "%s: address too long", 782 sep->se_service); 783 sep->se_checked = 0; 784 continue; 785 } 786 (void)unlink(sep->se_service); 787 strncpy(sep->se_ctrladdr_un.sun_path, 788 sep->se_service, n); 789 sep->se_ctrladdr_un.sun_family = AF_UNIX; 790 sep->se_ctrladdr_size = n + 791 sizeof(sep->se_ctrladdr_un) - 792 sizeof(sep->se_ctrladdr_un.sun_path); 793 if (!ISMUX(sep)) 794 setup(sep); 795 break; 796 case AF_INET: 797 sep->se_ctrladdr_in.sin_family = AF_INET; 798 if (!strcmp(sep->se_hostaddr,"*")) 799 sep->se_ctrladdr_in.sin_addr.s_addr = 800 INADDR_ANY; 801 else if (!inet_aton(sep->se_hostaddr, 802 &sep->se_ctrladdr_in.sin_addr)) { 803 /* Do we really want to support hostname lookups here? */ 804 struct hostent *hp; 805 hp = gethostbyname(sep->se_hostaddr); 806 if (hp == 0) { 807 syslog(LOG_ERR, "%s: unknown host", 808 sep->se_hostaddr); 809 sep->se_checked = 0; 810 continue; 811 } else if (hp->h_addrtype != AF_INET) { 812 syslog(LOG_ERR, 813 "%s: address isn't an Internet address", 814 sep->se_hostaddr); 815 sep->se_checked = 0; 816 continue; 817 } else if (hp->h_length != sizeof(struct in_addr)) { 818 syslog(LOG_ERR, 819 "%s: address size wrong (under DNS corruption attack?)", 820 sep->se_hostaddr); 821 sep->se_checked = 0; 822 continue; 823 } else { 824 memcpy(&sep->se_ctrladdr_in.sin_addr, 825 hp->h_addr_list[0], 826 sizeof(struct in_addr)); 827 } 828 } 829 if (ISMUX(sep)) { 830 sep->se_fd = -1; 831 continue; 832 } 833 sep->se_ctrladdr_size = sizeof(sep->se_ctrladdr_in); 834 if (isrpcservice(sep)) { 835 struct rpcent *rp; 836 837 sep->se_rpcprog = atoi(sep->se_service); 838 if (sep->se_rpcprog == 0) { 839 rp = getrpcbyname(sep->se_service); 840 if (rp == 0) { 841 syslog(LOG_ERR, 842 "%s/%s: unknown service", 843 sep->se_service, 844 sep->se_proto); 845 sep->se_checked = 0; 846 continue; 847 } 848 sep->se_rpcprog = rp->r_number; 849 } 850 if (sep->se_fd == -1 && !ISMUX(sep)) 851 setup(sep); 852 if (sep->se_fd != -1) 853 register_rpc(sep); 854 } else { 855 u_short port = htons(atoi(sep->se_service)); 856 857 if (!port) { 858 sp = getservbyname(sep->se_service, 859 sep->se_proto); 860 if (sp == 0) { 861 syslog(LOG_ERR, 862 "%s/%s: unknown service", 863 sep->se_service, 864 sep->se_proto); 865 sep->se_checked = 0; 866 continue; 867 } 868 port = sp->s_port; 869 } 870 if (port != sep->se_ctrladdr_in.sin_port) { 871 sep->se_ctrladdr_in.sin_port = port; 872 if (sep->se_fd >= 0) 873 close_sep(sep); 874 } 875 if (sep->se_fd == -1 && !ISMUX(sep)) 876 setup(sep); 877 } 878 } 879 } 880 endconfig(); 881 /* 882 * Purge anything not looked at above. 883 */ 884 omask = sigblock(SIGBLOCK); 885 sepp = &servtab; 886 while ((sep = *sepp)) { 887 if (sep->se_checked) { 888 sepp = &sep->se_next; 889 continue; 890 } 891 *sepp = sep->se_next; 892 if (sep->se_fd >= 0) 893 close_sep(sep); 894 if (isrpcservice(sep)) 895 unregister_rpc(sep); 896 if (sep->se_family == AF_UNIX) 897 (void)unlink(sep->se_service); 898 if (debug) 899 print_service("FREE", sep); 900 freeconfig(sep); 901 free((char *)sep); 902 } 903 (void) sigsetmask(omask); 904 } 905 906 void 907 retry(signo) 908 int signo; 909 { 910 struct servtab *sep; 911 912 timingout = 0; 913 for (sep = servtab; sep; sep = sep->se_next) { 914 if (sep->se_fd == -1 && !ISMUX(sep)) { 915 switch (sep->se_family) { 916 case AF_UNIX: 917 case AF_INET: 918 setup(sep); 919 if (sep->se_fd != -1 && isrpcservice(sep)) 920 register_rpc(sep); 921 break; 922 } 923 } 924 } 925 } 926 927 void 928 goaway(signo) 929 int signo; 930 { 931 struct servtab *sep; 932 933 for (sep = servtab; sep; sep = sep->se_next) { 934 if (sep->se_fd == -1) 935 continue; 936 937 switch (sep->se_family) { 938 case AF_UNIX: 939 (void)unlink(sep->se_service); 940 break; 941 case AF_INET: 942 if (sep->se_wait == 1 && isrpcservice(sep)) 943 unregister_rpc(sep); 944 break; 945 } 946 (void)close(sep->se_fd); 947 } 948 (void)unlink(_PATH_INETDPID); 949 exit(0); 950 } 951 952 void 953 setup(sep) 954 struct servtab *sep; 955 { 956 int on = 1; 957 958 if ((sep->se_fd = socket(sep->se_family, sep->se_socktype, 0)) < 0) { 959 if (debug) 960 fprintf(stderr, "socket failed on %s/%s: %s\n", 961 sep->se_service, sep->se_proto, strerror(errno)); 962 syslog(LOG_ERR, "%s/%s: socket: %m", 963 sep->se_service, sep->se_proto); 964 return; 965 } 966 /* Set all listening sockets to close-on-exec. */ 967 if (fcntl(sep->se_fd, F_SETFD, FD_CLOEXEC) < 0) 968 syslog(LOG_ERR, "fcntl (F_SETFD, FD_CLOEXEC): %m"); 969 #define turnon(fd, opt) \ 970 setsockopt(fd, SOL_SOCKET, opt, (char *)&on, sizeof (on)) 971 if (strcmp(sep->se_proto, "tcp") == 0 && (options & SO_DEBUG) && 972 turnon(sep->se_fd, SO_DEBUG) < 0) 973 syslog(LOG_ERR, "setsockopt (SO_DEBUG): %m"); 974 if (turnon(sep->se_fd, SO_REUSEADDR) < 0) 975 syslog(LOG_ERR, "setsockopt (SO_REUSEADDR): %m"); 976 #undef turnon 977 if (bind(sep->se_fd, &sep->se_ctrladdr, sep->se_ctrladdr_size) < 0) { 978 if (debug) 979 fprintf(stderr, "bind failed on %s/%s: %s\n", 980 sep->se_service, sep->se_proto, strerror(errno)); 981 syslog(LOG_ERR, "%s/%s: bind: %m", 982 sep->se_service, sep->se_proto); 983 (void) close(sep->se_fd); 984 sep->se_fd = -1; 985 if (!timingout) { 986 timingout = 1; 987 alarm(RETRYTIME); 988 } 989 return; 990 } 991 if (sep->se_socktype == SOCK_STREAM) 992 listen(sep->se_fd, 10); 993 994 FD_SET(sep->se_fd, &allsock); 995 nsock++; 996 if (sep->se_fd > maxsock) { 997 maxsock = sep->se_fd; 998 if (maxsock > rlim_ofile_cur - FD_MARGIN) 999 bump_nofile(); 1000 } 1001 if (debug) 1002 fprintf(stderr, "registered %s on %d\n", 1003 sep->se_server, sep->se_fd); 1004 } 1005 1006 /* 1007 * Finish with a service and its socket. 1008 */ 1009 void 1010 close_sep(sep) 1011 struct servtab *sep; 1012 { 1013 if (sep->se_fd >= 0) { 1014 nsock--; 1015 FD_CLR(sep->se_fd, &allsock); 1016 (void) close(sep->se_fd); 1017 sep->se_fd = -1; 1018 } 1019 sep->se_count = 0; 1020 /* 1021 * Don't keep the pid of this running deamon: when reapchild() 1022 * reaps this pid, it would erroneously increment nsock. 1023 */ 1024 if (sep->se_wait > 1) 1025 sep->se_wait = 1; 1026 } 1027 1028 void 1029 register_rpc(sep) 1030 struct servtab *sep; 1031 { 1032 #ifdef RPC 1033 int n; 1034 struct sockaddr_in sin; 1035 struct protoent *pp; 1036 1037 if ((pp = getprotobyname(sep->se_proto+4)) == NULL) { 1038 syslog(LOG_ERR, "%s: getproto: %m", 1039 sep->se_proto); 1040 return; 1041 } 1042 n = sizeof sin; 1043 if (getsockname(sep->se_fd, (struct sockaddr *)&sin, &n) < 0) { 1044 syslog(LOG_ERR, "%s/%s: getsockname: %m", 1045 sep->se_service, sep->se_proto); 1046 return; 1047 } 1048 1049 for (n = sep->se_rpcversl; n <= sep->se_rpcversh; n++) { 1050 if (debug) 1051 fprintf(stderr, "pmap_set: %u %u %u %u\n", 1052 sep->se_rpcprog, n, pp->p_proto, 1053 ntohs(sin.sin_port)); 1054 (void)pmap_unset(sep->se_rpcprog, n); 1055 if (!pmap_set(sep->se_rpcprog, n, pp->p_proto, ntohs(sin.sin_port))) 1056 syslog(LOG_ERR, "pmap_set: %u %u %u %u: %m", 1057 sep->se_rpcprog, n, pp->p_proto, 1058 ntohs(sin.sin_port)); 1059 } 1060 #endif /* RPC */ 1061 } 1062 1063 void 1064 unregister_rpc(sep) 1065 struct servtab *sep; 1066 { 1067 #ifdef RPC 1068 int n; 1069 1070 for (n = sep->se_rpcversl; n <= sep->se_rpcversh; n++) { 1071 if (debug) 1072 fprintf(stderr, "pmap_unset(%u, %u)\n", 1073 sep->se_rpcprog, n); 1074 if (!pmap_unset(sep->se_rpcprog, n)) 1075 syslog(LOG_ERR, "pmap_unset(%u, %u)\n", 1076 sep->se_rpcprog, n); 1077 } 1078 #endif /* RPC */ 1079 } 1080 1081 1082 struct servtab * 1083 enter(cp) 1084 struct servtab *cp; 1085 { 1086 struct servtab *sep; 1087 long omask; 1088 1089 sep = (struct servtab *)malloc(sizeof (*sep)); 1090 if (sep == (struct servtab *)0) { 1091 syslog(LOG_ERR, "Out of memory."); 1092 exit(-1); 1093 } 1094 *sep = *cp; 1095 sep->se_fd = -1; 1096 sep->se_rpcprog = -1; 1097 omask = sigblock(SIGBLOCK); 1098 sep->se_next = servtab; 1099 servtab = sep; 1100 sigsetmask(omask); 1101 return (sep); 1102 } 1103 1104 FILE *fconfig = NULL; 1105 struct servtab serv; 1106 char line[LINE_MAX]; 1107 char *defhost; 1108 1109 int 1110 setconfig() 1111 { 1112 if (defhost) free(defhost); 1113 defhost = newstr("*"); 1114 if (fconfig != NULL) { 1115 fseek(fconfig, 0L, SEEK_SET); 1116 return (1); 1117 } 1118 fconfig = fopen(CONFIG, "r"); 1119 return (fconfig != NULL); 1120 } 1121 1122 void 1123 endconfig() 1124 { 1125 if (fconfig) { 1126 (void) fclose(fconfig); 1127 fconfig = NULL; 1128 } 1129 if (defhost) { 1130 free(defhost); 1131 defhost = 0; 1132 } 1133 } 1134 1135 struct servtab * 1136 getconfigent() 1137 { 1138 struct servtab *sep = &serv; 1139 int argc; 1140 char *cp, *arg; 1141 static char TCPMUX_TOKEN[] = "tcpmux/"; 1142 #define MUX_LEN (sizeof(TCPMUX_TOKEN)-1) 1143 char *hostdelim; 1144 1145 more: 1146 #ifdef MULOG 1147 while ((cp = nextline(fconfig)) && (*cp == '#' || *cp == '\0')) { 1148 /* Avoid use of `skip' if there is a danger of it looking 1149 * at continuation lines. 1150 */ 1151 do { 1152 cp++; 1153 } while (*cp == ' ' || *cp == '\t'); 1154 if (*cp == '\0') 1155 continue; 1156 if ((arg = skip(&cp)) == NULL) 1157 continue; 1158 if (strcmp(arg, "DOMAIN")) 1159 continue; 1160 if (curdom) 1161 free(curdom); 1162 curdom = NULL; 1163 while (*cp == ' ' || *cp == '\t') 1164 cp++; 1165 if (*cp == '\0') 1166 continue; 1167 arg = cp; 1168 while (*cp && *cp != ' ' && *cp != '\t') 1169 cp++; 1170 if (*cp != '\0') 1171 *cp++ = '\0'; 1172 curdom = newstr(arg); 1173 } 1174 #else 1175 while ((cp = nextline(fconfig)) && (*cp == '#' || *cp == '\0')) 1176 ; 1177 #endif 1178 if (cp == NULL) 1179 return ((struct servtab *)0); 1180 /* 1181 * clear the static buffer, since some fields (se_ctrladdr, 1182 * for example) don't get initialized here. 1183 */ 1184 memset((caddr_t)sep, 0, sizeof *sep); 1185 arg = skip(&cp); 1186 if (cp == NULL) { 1187 /* got an empty line containing just blanks/tabs. */ 1188 goto more; 1189 } 1190 /* Check for a host name. */ 1191 hostdelim = strrchr(arg, ':'); 1192 if (hostdelim) { 1193 *hostdelim = '\0'; 1194 sep->se_hostaddr = newstr(arg); 1195 arg = hostdelim + 1; 1196 /* 1197 * If the line is of the form `host:', then just change the 1198 * default host for the following lines. 1199 */ 1200 if (*arg == '\0') { 1201 arg = skip(&cp); 1202 if (cp == NULL) { 1203 free(defhost); 1204 defhost = sep->se_hostaddr; 1205 goto more; 1206 } 1207 } 1208 } else 1209 sep->se_hostaddr = newstr(defhost); 1210 if (strncmp(arg, TCPMUX_TOKEN, MUX_LEN) == 0) { 1211 char *c = arg + MUX_LEN; 1212 if (*c == '+') { 1213 sep->se_type = MUXPLUS_TYPE; 1214 c++; 1215 } else 1216 sep->se_type = MUX_TYPE; 1217 sep->se_service = newstr(c); 1218 } else { 1219 sep->se_service = newstr(arg); 1220 sep->se_type = NORM_TYPE; 1221 } 1222 1223 arg = sskip(&cp); 1224 if (strcmp(arg, "stream") == 0) 1225 sep->se_socktype = SOCK_STREAM; 1226 else if (strcmp(arg, "dgram") == 0) 1227 sep->se_socktype = SOCK_DGRAM; 1228 else if (strcmp(arg, "rdm") == 0) 1229 sep->se_socktype = SOCK_RDM; 1230 else if (strcmp(arg, "seqpacket") == 0) 1231 sep->se_socktype = SOCK_SEQPACKET; 1232 else if (strcmp(arg, "raw") == 0) 1233 sep->se_socktype = SOCK_RAW; 1234 else 1235 sep->se_socktype = -1; 1236 1237 sep->se_proto = newstr(sskip(&cp)); 1238 if (strcmp(sep->se_proto, "unix") == 0) { 1239 sep->se_family = AF_UNIX; 1240 } else { 1241 sep->se_family = AF_INET; 1242 if (strncmp(sep->se_proto, "rpc/", 4) == 0) { 1243 #ifdef RPC 1244 char *cp, *ccp; 1245 cp = strchr(sep->se_service, '/'); 1246 if (cp == 0) { 1247 syslog(LOG_ERR, "%s: no rpc version", 1248 sep->se_service); 1249 goto more; 1250 } 1251 *cp++ = '\0'; 1252 sep->se_rpcversl = sep->se_rpcversh = 1253 strtol(cp, &ccp, 0); 1254 if (ccp == cp) { 1255 badafterall: 1256 syslog(LOG_ERR, "%s/%s: bad rpc version", 1257 sep->se_service, cp); 1258 goto more; 1259 } 1260 if (*ccp == '-') { 1261 cp = ccp + 1; 1262 sep->se_rpcversh = strtol(cp, &ccp, 0); 1263 if (ccp == cp) 1264 goto badafterall; 1265 } 1266 #else 1267 syslog(LOG_ERR, "%s: rpc services not suported", 1268 sep->se_service); 1269 goto more; 1270 #endif /* RPC */ 1271 } 1272 } 1273 arg = sskip(&cp); 1274 { 1275 char *cp; 1276 cp = strchr(arg, '.'); 1277 if (cp) { 1278 *cp++ = '\0'; 1279 sep->se_max = atoi(cp); 1280 } else 1281 sep->se_max = TOOMANY; 1282 } 1283 sep->se_wait = strcmp(arg, "wait") == 0; 1284 if (ISMUX(sep)) { 1285 /* 1286 * Silently enforce "nowait" for TCPMUX services since 1287 * they don't have an assigned port to listen on. 1288 */ 1289 sep->se_wait = 0; 1290 1291 if (strcmp(sep->se_proto, "tcp")) { 1292 syslog(LOG_ERR, 1293 "%s: bad protocol for tcpmux service %s", 1294 CONFIG, sep->se_service); 1295 goto more; 1296 } 1297 if (sep->se_socktype != SOCK_STREAM) { 1298 syslog(LOG_ERR, 1299 "%s: bad socket type for tcpmux service %s", 1300 CONFIG, sep->se_service); 1301 goto more; 1302 } 1303 } 1304 sep->se_user = newstr(sskip(&cp)); 1305 if ((sep->se_group = strchr(sep->se_user, '.'))) 1306 *sep->se_group++ = '\0'; 1307 sep->se_server = newstr(sskip(&cp)); 1308 if (strcmp(sep->se_server, "internal") == 0) { 1309 struct biltin *bi; 1310 1311 for (bi = biltins; bi->bi_service; bi++) 1312 if (bi->bi_socktype == sep->se_socktype && 1313 strcmp(bi->bi_service, sep->se_service) == 0) 1314 break; 1315 if (bi->bi_service == 0) { 1316 syslog(LOG_ERR, "internal service %s unknown", 1317 sep->se_service); 1318 goto more; 1319 } 1320 sep->se_bi = bi; 1321 sep->se_wait = bi->bi_wait; 1322 } else 1323 sep->se_bi = NULL; 1324 argc = 0; 1325 for (arg = skip(&cp); cp; arg = skip(&cp)) { 1326 #if MULOG 1327 char *colon; 1328 1329 if (argc == 0 && (colon = strrchr(arg, ':'))) { 1330 while (arg < colon) { 1331 int x; 1332 char *ccp; 1333 1334 switch (*arg++) { 1335 case 'l': 1336 x = 1; 1337 if (isdigit(*arg)) { 1338 x = strtol(arg, &ccp, 0); 1339 if (ccp == arg) 1340 break; 1341 arg = ccp; 1342 } 1343 sep->se_log &= ~MULOG_RFC931; 1344 sep->se_log |= x; 1345 break; 1346 case 'a': 1347 sep->se_log |= MULOG_RFC931; 1348 break; 1349 default: 1350 break; 1351 } 1352 } 1353 arg = colon + 1; 1354 } 1355 #endif 1356 if (argc < MAXARGV) 1357 sep->se_argv[argc++] = newstr(arg); 1358 } 1359 while (argc <= MAXARGV) 1360 sep->se_argv[argc++] = NULL; 1361 return (sep); 1362 } 1363 1364 void 1365 freeconfig(cp) 1366 struct servtab *cp; 1367 { 1368 int i; 1369 1370 if (cp->se_hostaddr) 1371 free(cp->se_hostaddr); 1372 if (cp->se_service) 1373 free(cp->se_service); 1374 if (cp->se_proto) 1375 free(cp->se_proto); 1376 if (cp->se_user) 1377 free(cp->se_user); 1378 /* Note: se_group is part of the newstr'ed se_user */ 1379 if (cp->se_server) 1380 free(cp->se_server); 1381 for (i = 0; i < MAXARGV; i++) 1382 if (cp->se_argv[i]) 1383 free(cp->se_argv[i]); 1384 } 1385 1386 1387 /* 1388 * Safe skip - if skip returns null, log a syntax error in the 1389 * configuration file and exit. 1390 */ 1391 char * 1392 sskip(cpp) 1393 char **cpp; 1394 { 1395 char *cp; 1396 1397 cp = skip(cpp); 1398 if (cp == NULL) { 1399 syslog(LOG_ERR, "%s: syntax error", CONFIG); 1400 exit(-1); 1401 } 1402 return (cp); 1403 } 1404 1405 char * 1406 skip(cpp) 1407 char **cpp; 1408 { 1409 char *cp = *cpp; 1410 char *start; 1411 1412 if (*cpp == NULL) 1413 return ((char *)0); 1414 1415 again: 1416 while (*cp == ' ' || *cp == '\t') 1417 cp++; 1418 if (*cp == '\0') { 1419 int c; 1420 1421 c = getc(fconfig); 1422 (void) ungetc(c, fconfig); 1423 if (c == ' ' || c == '\t') 1424 if ((cp = nextline(fconfig))) 1425 goto again; 1426 *cpp = (char *)0; 1427 return ((char *)0); 1428 } 1429 start = cp; 1430 while (*cp && *cp != ' ' && *cp != '\t') 1431 cp++; 1432 if (*cp != '\0') 1433 *cp++ = '\0'; 1434 *cpp = cp; 1435 return (start); 1436 } 1437 1438 char * 1439 nextline(fd) 1440 FILE *fd; 1441 { 1442 char *cp; 1443 1444 if (fgets(line, sizeof (line), fd) == NULL) 1445 return ((char *)0); 1446 cp = strchr(line, '\n'); 1447 if (cp) 1448 *cp = '\0'; 1449 return (line); 1450 } 1451 1452 char * 1453 newstr(cp) 1454 char *cp; 1455 { 1456 if ((cp = strdup(cp ? cp : ""))) 1457 return (cp); 1458 syslog(LOG_ERR, "strdup: %m"); 1459 exit(-1); 1460 } 1461 1462 void 1463 inetd_setproctitle(a, s) 1464 char *a; 1465 int s; 1466 { 1467 int size; 1468 char *cp; 1469 struct sockaddr_in sin; 1470 char buf[80]; 1471 1472 cp = Argv[0]; 1473 size = sizeof(sin); 1474 if (getpeername(s, (struct sockaddr *)&sin, &size) == 0) 1475 (void)snprintf(buf, sizeof buf, "-%s [%s]", a, 1476 inet_ntoa(sin.sin_addr)); 1477 else 1478 (void)snprintf(buf, sizeof buf, "-%s", a); 1479 strncpy(cp, buf, LastArg - cp); 1480 cp += strlen(cp); 1481 while (cp < LastArg) 1482 *cp++ = ' '; 1483 } 1484 1485 void 1486 logpid() 1487 { 1488 FILE *fp; 1489 1490 if ((fp = fopen(_PATH_INETDPID, "w")) != NULL) { 1491 fprintf(fp, "%u\n", getpid()); 1492 (void)fclose(fp); 1493 } 1494 } 1495 1496 void 1497 bump_nofile() 1498 { 1499 #ifdef RLIMIT_NOFILE 1500 1501 #define FD_CHUNK 32 1502 1503 struct rlimit rl; 1504 1505 if (getrlimit(RLIMIT_NOFILE, &rl) < 0) { 1506 syslog(LOG_ERR, "getrlimit: %m"); 1507 return; 1508 } 1509 rl.rlim_cur = MIN(rl.rlim_max, rl.rlim_cur + FD_CHUNK); 1510 if (rl.rlim_cur <= rlim_ofile_cur) { 1511 syslog(LOG_ERR, 1512 "bump_nofile: cannot extend file limit, max = %d", 1513 (int)rl.rlim_cur); 1514 return; 1515 } 1516 1517 if (setrlimit(RLIMIT_NOFILE, &rl) < 0) { 1518 syslog(LOG_ERR, "setrlimit: %m"); 1519 return; 1520 } 1521 1522 rlim_ofile_cur = rl.rlim_cur; 1523 return; 1524 1525 #else 1526 syslog(LOG_ERR, "bump_nofile: cannot extend file limit"); 1527 return; 1528 #endif 1529 } 1530 1531 /* 1532 * Internet services provided internally by inetd: 1533 */ 1534 #define BUFSIZE 4096 1535 1536 /* ARGSUSED */ 1537 void 1538 echo_stream(s, sep) /* Echo service -- echo data back */ 1539 int s; 1540 struct servtab *sep; 1541 { 1542 char buffer[BUFSIZE]; 1543 int i; 1544 1545 inetd_setproctitle(sep->se_service, s); 1546 while ((i = read(s, buffer, sizeof(buffer))) > 0 && 1547 write(s, buffer, i) > 0) 1548 ; 1549 } 1550 1551 /* ARGSUSED */ 1552 void 1553 echo_dg(s, sep) /* Echo service -- echo data back */ 1554 int s; 1555 struct servtab *sep; 1556 { 1557 char buffer[BUFSIZE]; 1558 int i, size; 1559 struct sockaddr sa; 1560 1561 size = sizeof(sa); 1562 if ((i = recvfrom(s, buffer, sizeof(buffer), 0, &sa, &size)) < 0) 1563 return; 1564 (void) sendto(s, buffer, i, 0, &sa, sizeof(sa)); 1565 } 1566 1567 /* ARGSUSED */ 1568 void 1569 discard_stream(s, sep) /* Discard service -- ignore data */ 1570 int s; 1571 struct servtab *sep; 1572 { 1573 char buffer[BUFSIZE]; 1574 1575 inetd_setproctitle(sep->se_service, s); 1576 while ((errno = 0, read(s, buffer, sizeof(buffer)) > 0) || 1577 errno == EINTR) 1578 ; 1579 } 1580 1581 /* ARGSUSED */ 1582 void 1583 discard_dg(s, sep) /* Discard service -- ignore data */ 1584 int s; 1585 struct servtab *sep; 1586 { 1587 char buffer[BUFSIZE]; 1588 1589 (void) read(s, buffer, sizeof(buffer)); 1590 } 1591 1592 #include <ctype.h> 1593 #define LINESIZ 72 1594 char ring[128]; 1595 char *endring; 1596 1597 void 1598 initring() 1599 { 1600 int i; 1601 1602 endring = ring; 1603 1604 for (i = 0; i <= 128; ++i) 1605 if (isprint(i)) 1606 *endring++ = i; 1607 } 1608 1609 /* ARGSUSED */ 1610 void 1611 chargen_stream(s, sep) /* Character generator */ 1612 int s; 1613 struct servtab *sep; 1614 { 1615 int len; 1616 char *rs, text[LINESIZ+2]; 1617 1618 inetd_setproctitle(sep->se_service, s); 1619 1620 if (!endring) { 1621 initring(); 1622 rs = ring; 1623 } 1624 1625 text[LINESIZ] = '\r'; 1626 text[LINESIZ + 1] = '\n'; 1627 for (rs = ring;;) { 1628 if ((len = endring - rs) >= LINESIZ) 1629 memmove(text, rs, LINESIZ); 1630 else { 1631 memmove(text, rs, len); 1632 memmove(text + len, ring, LINESIZ - len); 1633 } 1634 if (++rs == endring) 1635 rs = ring; 1636 if (write(s, text, sizeof(text)) != sizeof(text)) 1637 break; 1638 } 1639 } 1640 1641 /* ARGSUSED */ 1642 void 1643 chargen_dg(s, sep) /* Character generator */ 1644 int s; 1645 struct servtab *sep; 1646 { 1647 struct sockaddr sa; 1648 static char *rs; 1649 int len, size; 1650 char text[LINESIZ+2]; 1651 1652 if (endring == 0) { 1653 initring(); 1654 rs = ring; 1655 } 1656 1657 size = sizeof(sa); 1658 if (recvfrom(s, text, sizeof(text), 0, &sa, &size) < 0) 1659 return; 1660 1661 if ((len = endring - rs) >= LINESIZ) 1662 memmove(text, rs, LINESIZ); 1663 else { 1664 memmove(text, rs, len); 1665 memmove(text + len, ring, LINESIZ - len); 1666 } 1667 if (++rs == endring) 1668 rs = ring; 1669 text[LINESIZ] = '\r'; 1670 text[LINESIZ + 1] = '\n'; 1671 (void) sendto(s, text, sizeof(text), 0, &sa, sizeof(sa)); 1672 } 1673 1674 /* 1675 * Return a machine readable date and time, in the form of the 1676 * number of seconds since midnight, Jan 1, 1900. Since gettimeofday 1677 * returns the number of seconds since midnight, Jan 1, 1970, 1678 * we must add 2208988800 seconds to this figure to make up for 1679 * some seventy years Bell Labs was asleep. 1680 */ 1681 1682 long 1683 machtime() 1684 { 1685 struct timeval tv; 1686 1687 if (gettimeofday(&tv, (struct timezone *)0) < 0) { 1688 if (debug) 1689 fprintf(stderr, "Unable to get time of day\n"); 1690 return (0L); 1691 } 1692 #define OFFSET ((u_long)25567 * 24*60*60) 1693 return (htonl((long)(tv.tv_sec + OFFSET))); 1694 #undef OFFSET 1695 } 1696 1697 /* ARGSUSED */ 1698 void 1699 machtime_stream(s, sep) 1700 int s; 1701 struct servtab *sep; 1702 { 1703 long result; 1704 1705 result = machtime(); 1706 (void) write(s, (char *) &result, sizeof(result)); 1707 } 1708 1709 /* ARGSUSED */ 1710 void 1711 machtime_dg(s, sep) 1712 int s; 1713 struct servtab *sep; 1714 { 1715 long result; 1716 struct sockaddr sa; 1717 int size; 1718 1719 size = sizeof(sa); 1720 if (recvfrom(s, (char *)&result, sizeof(result), 0, &sa, &size) < 0) 1721 return; 1722 result = machtime(); 1723 (void) sendto(s, (char *) &result, sizeof(result), 0, &sa, sizeof(sa)); 1724 } 1725 1726 /* ARGSUSED */ 1727 void 1728 daytime_stream(s, sep) /* Return human-readable time of day */ 1729 int s; 1730 struct servtab *sep; 1731 { 1732 char buffer[256]; 1733 time_t clock; 1734 int len; 1735 1736 clock = time((time_t *) 0); 1737 1738 len = snprintf(buffer, sizeof buffer, "%.24s\r\n", ctime(&clock)); 1739 (void) write(s, buffer, len); 1740 } 1741 1742 /* ARGSUSED */ 1743 void 1744 daytime_dg(s, sep) /* Return human-readable time of day */ 1745 int s; 1746 struct servtab *sep; 1747 { 1748 char buffer[256]; 1749 time_t clock; 1750 struct sockaddr sa; 1751 int size, len; 1752 1753 clock = time((time_t *) 0); 1754 1755 size = sizeof(sa); 1756 if (recvfrom(s, buffer, sizeof(buffer), 0, &sa, &size) < 0) 1757 return; 1758 len = snprintf(buffer, sizeof buffer, "%.24s\r\n", ctime(&clock)); 1759 (void) sendto(s, buffer, len, 0, &sa, sizeof(sa)); 1760 } 1761 1762 /* 1763 * print_service: 1764 * Dump relevant information to stderr 1765 */ 1766 void 1767 print_service(action, sep) 1768 char *action; 1769 struct servtab *sep; 1770 { 1771 if (isrpcservice(sep)) 1772 fprintf(stderr, 1773 "%s: %s rpcprog=%d, rpcvers = %d/%d, proto=%s, wait.max=%d.%d, user.group=%s.%s builtin=%lx server=%s\n", 1774 action, sep->se_service, 1775 sep->se_rpcprog, sep->se_rpcversh, sep->se_rpcversl, sep->se_proto, 1776 sep->se_wait, sep->se_max, sep->se_user, sep->se_group, 1777 (long)sep->se_bi, sep->se_server); 1778 else 1779 fprintf(stderr, 1780 "%s: %s proto=%s, wait.max=%d.%d, user.group=%s.%s builtin=%lx server=%s\n", 1781 action, sep->se_service, sep->se_proto, 1782 sep->se_wait, sep->se_max, sep->se_user, sep->se_group, 1783 (long)sep->se_bi, sep->se_server); 1784 } 1785 1786 void 1787 usage() 1788 { 1789 1790 #ifdef LIBWRAP 1791 (void)fprintf(stderr, "usage: %s [-dl] [conf]\n", __progname); 1792 #else 1793 (void)fprintf(stderr, "usage: %s [-d] [conf]\n", __progname); 1794 #endif 1795 exit(1); 1796 } 1797 1798 1799 /* 1800 * Based on TCPMUX.C by Mark K. Lottor November 1988 1801 * sri-nic::ps:<mkl>tcpmux.c 1802 */ 1803 1804 static int /* # of characters upto \r,\n or \0 */ 1805 getline(fd, buf, len) 1806 int fd; 1807 char *buf; 1808 int len; 1809 { 1810 int count = 0, n; 1811 1812 do { 1813 n = read(fd, buf, len-count); 1814 if (n == 0) 1815 return (count); 1816 if (n < 0) 1817 return (-1); 1818 while (--n >= 0) { 1819 if (*buf == '\r' || *buf == '\n' || *buf == '\0') 1820 return (count); 1821 count++; 1822 buf++; 1823 } 1824 } while (count < len); 1825 return (count); 1826 } 1827 1828 #define MAX_SERV_LEN (256+2) /* 2 bytes for \r\n */ 1829 1830 #define strwrite(fd, buf) (void) write(fd, buf, sizeof(buf)-1) 1831 1832 void 1833 tcpmux(ctrl, sep) 1834 int ctrl; 1835 struct servtab *sep; 1836 { 1837 char service[MAX_SERV_LEN+1]; 1838 int len; 1839 1840 /* Get requested service name */ 1841 if ((len = getline(ctrl, service, MAX_SERV_LEN)) < 0) { 1842 strwrite(ctrl, "-Error reading service name\r\n"); 1843 goto reject; 1844 } 1845 service[len] = '\0'; 1846 1847 if (debug) 1848 fprintf(stderr, "tcpmux: someone wants %s\n", service); 1849 1850 /* 1851 * Help is a required command, and lists available services, 1852 * one per line. 1853 */ 1854 if (!strcasecmp(service, "help")) { 1855 strwrite(ctrl, "+Available services:\r\n"); 1856 strwrite(ctrl, "help\r\n"); 1857 for (sep = servtab; sep; sep = sep->se_next) { 1858 if (!ISMUX(sep)) 1859 continue; 1860 (void)write(ctrl, sep->se_service, 1861 strlen(sep->se_service)); 1862 strwrite(ctrl, "\r\n"); 1863 } 1864 goto reject; 1865 } 1866 1867 /* Try matching a service in inetd.conf with the request */ 1868 for (sep = servtab; sep; sep = sep->se_next) { 1869 if (!ISMUX(sep)) 1870 continue; 1871 if (!strcasecmp(service, sep->se_service)) { 1872 if (ISMUXPLUS(sep)) 1873 strwrite(ctrl, "+Go\r\n"); 1874 run_service(ctrl, sep); 1875 return; 1876 } 1877 } 1878 strwrite(ctrl, "-Service not available\r\n"); 1879 reject: 1880 _exit(1); 1881 } 1882 1883 1884 #ifdef MULOG 1885 dolog(sep, ctrl) 1886 struct servtab *sep; 1887 int ctrl; 1888 { 1889 struct sockaddr sa; 1890 struct sockaddr_in *sin = (struct sockaddr_in *)&sa; 1891 int len = sizeof(sa); 1892 struct hostent *hp; 1893 char *host, *dp, buf[BUFSIZ], *rfc931_name(); 1894 int connected = 1; 1895 1896 if (sep->se_family != AF_INET) 1897 return; 1898 1899 if (getpeername(ctrl, &sa, &len) < 0) { 1900 if (errno != ENOTCONN) { 1901 syslog(LOG_ERR, "getpeername: %m"); 1902 return; 1903 } 1904 if (recvfrom(ctrl, buf, sizeof(buf), MSG_PEEK, &sa, &len) < 0) { 1905 syslog(LOG_ERR, "recvfrom: %m"); 1906 return; 1907 } 1908 connected = 0; 1909 } 1910 if (sa.sa_family != AF_INET) { 1911 syslog(LOG_ERR, "unexpected address family %u", sa.sa_family); 1912 return; 1913 } 1914 1915 hp = gethostbyaddr((char *) &sin->sin_addr.s_addr, 1916 sizeof (sin->sin_addr.s_addr), AF_INET); 1917 1918 host = hp?hp->h_name:inet_ntoa(sin->sin_addr); 1919 1920 switch (sep->se_log & ~MULOG_RFC931) { 1921 case 0: 1922 return; 1923 case 1: 1924 if (curdom == NULL || *curdom == '\0') 1925 break; 1926 dp = host + strlen(host) - strlen(curdom); 1927 if (dp < host) 1928 break; 1929 if (debug) 1930 fprintf(stderr, "check \"%s\" against curdom \"%s\"\n", 1931 host, curdom); 1932 if (strcasecmp(dp, curdom) == 0) 1933 return; 1934 break; 1935 case 2: 1936 default: 1937 break; 1938 } 1939 1940 openlog("", LOG_NOWAIT, MULOG); 1941 1942 if (connected && (sep->se_log & MULOG_RFC931)) 1943 syslog(LOG_INFO, "%s@%s wants %s", 1944 rfc931_name(sin, ctrl), host, sep->se_service); 1945 else 1946 syslog(LOG_INFO, "%s wants %s", 1947 host, sep->se_service); 1948 } 1949 1950 /* 1951 * From tcp_log by 1952 * Wietse Venema, Eindhoven University of Technology, The Netherlands. 1953 */ 1954 #if 0 1955 static char sccsid[] = "@(#) rfc931.c 1.3 92/08/31 22:54:46"; 1956 #endif 1957 1958 #include <setjmp.h> 1959 1960 #define RFC931_PORT 113 /* Semi-well-known port */ 1961 #define TIMEOUT 4 1962 #define TIMEOUT2 10 1963 1964 static jmp_buf timebuf; 1965 1966 /* timeout - handle timeouts */ 1967 1968 static void timeout(sig) 1969 int sig; 1970 { 1971 longjmp(timebuf, sig); 1972 } 1973 1974 /* rfc931_name - return remote user name */ 1975 1976 char * 1977 rfc931_name(there, ctrl) 1978 struct sockaddr_in *there; /* remote link information */ 1979 int ctrl; 1980 { 1981 struct sockaddr_in here; /* local link information */ 1982 struct sockaddr_in sin; /* for talking to RFC931 daemon */ 1983 int length; 1984 int s; 1985 unsigned remote; 1986 unsigned local; 1987 static char user[256]; /* XXX */ 1988 char buf[256]; 1989 char *cp; 1990 char *result = "USER_UNKNOWN"; 1991 int len; 1992 1993 /* Find out local port number of our stdin. */ 1994 1995 length = sizeof(here); 1996 if (getsockname(ctrl, (struct sockaddr *) &here, &length) == -1) { 1997 syslog(LOG_ERR, "getsockname: %m"); 1998 return (result); 1999 } 2000 /* Set up timer so we won't get stuck. */ 2001 2002 if ((s = socket(AF_INET, SOCK_STREAM, 0)) == -1) { 2003 syslog(LOG_ERR, "socket: %m"); 2004 return (result); 2005 } 2006 2007 sin = here; 2008 sin.sin_port = htons(0); 2009 if (bind(s, (struct sockaddr *) &sin, sizeof(sin)) == -1) { 2010 syslog(LOG_ERR, "bind: %m"); 2011 return (result); 2012 } 2013 2014 signal(SIGALRM, timeout); 2015 if (setjmp(timebuf)) { 2016 close(s); /* not: fclose(fp) */ 2017 return (result); 2018 } 2019 alarm(TIMEOUT); 2020 2021 /* Connect to the RFC931 daemon. */ 2022 2023 sin = *there; 2024 sin.sin_port = htons(RFC931_PORT); 2025 if (connect(s, (struct sockaddr *) &sin, sizeof(sin)) == -1) { 2026 close(s); 2027 alarm(0); 2028 return (result); 2029 } 2030 2031 /* Query the RFC 931 server. Would 13-byte writes ever be broken up? */ 2032 (void)snprintf(buf, sizeof buf, "%u,%u\r\n", ntohs(there->sin_port), 2033 ntohs(here.sin_port)); 2034 2035 2036 for (len = 0, cp = buf; len < strlen(buf); ) { 2037 int n; 2038 2039 if ((n = write(s, cp, strlen(buf) - len)) == -1) { 2040 close(s); 2041 alarm(0); 2042 return (result); 2043 } 2044 cp += n; 2045 len += n; 2046 } 2047 2048 /* Read response */ 2049 for (cp = buf; cp < buf + sizeof(buf) - 1; ) { 2050 char c; 2051 if (read(s, &c, 1) != 1) { 2052 close(s); 2053 alarm(0); 2054 return (result); 2055 } 2056 if (c == '\n') 2057 break; 2058 *cp++ = c; 2059 } 2060 *cp = '\0'; 2061 2062 if (sscanf(buf, "%u , %u : USERID :%*[^:]:%255s", &remote, &local, user) == 3 2063 && ntohs(there->sin_port) == remote 2064 && ntohs(here.sin_port) == local) { 2065 2066 /* Strip trailing carriage return. */ 2067 if (cp = strchr(user, '\r')) 2068 *cp = 0; 2069 result = user; 2070 } 2071 2072 alarm(0); 2073 close(s); 2074 return (result); 2075 } 2076 #endif 2077
Indexes created Tue Oct 21 19:09:51 GMT 2025