inetd.c revision 1.41
1 /* $NetBSD: inetd.c,v 1.41 1998/03/21 06:25:37 mycroft 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 1.41 1998/03/21 06:25:37 mycroft 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 close_sep(sep); 524 sigsetmask(0L); 525 if (!timingout) { 526 timingout = 1; 527 alarm(RETRYTIME); 528 } 529 continue; 530 } 531 } 532 pid = fork(); 533 if (pid < 0) { 534 syslog(LOG_ERR, "fork: %m"); 535 if (!sep->se_wait && sep->se_socktype == SOCK_STREAM) 536 close(ctrl); 537 sigsetmask(0L); 538 sleep(1); 539 continue; 540 } 541 if (pid != 0 && sep->se_wait) { 542 sep->se_wait = pid; 543 FD_CLR(sep->se_fd, &allsock); 544 nsock--; 545 } 546 if (pid == 0) { 547 sv.sv_mask = 0L; 548 sv.sv_handler = SIG_DFL; 549 sigvec(SIGPIPE, &sv, (struct sigvec *)0); 550 if (debug) 551 setsid(); 552 } 553 } 554 sigsetmask(0L); 555 if (pid == 0) { 556 run_service(ctrl, sep); 557 if (dofork) 558 exit(0); 559 } 560 if (!sep->se_wait && sep->se_socktype == SOCK_STREAM) 561 close(ctrl); 562 } 563 } 564 } 565 } 566 567 void 568 run_service(ctrl, sep) 569 int ctrl; 570 struct servtab *sep; 571 { 572 struct passwd *pwd; 573 struct group *grp = NULL; /* XXX gcc */ 574 char buf[7]; 575 #ifdef LIBWRAP 576 struct request_info req; 577 int denied; 578 char *service = NULL; /* XXX gcc */ 579 #endif 580 581 #ifdef LIBWRAP 582 #ifndef LIBWRAP_INTERNAL 583 if (sep->se_bi == 0) 584 #endif 585 if (!sep->se_wait && sep->se_socktype == SOCK_STREAM) { 586 request_init(&req, RQ_DAEMON, sep->se_argv[0] ? 587 sep->se_argv[0] : sep->se_service, RQ_FILE, ctrl, NULL); 588 fromhost(&req); 589 denied = !hosts_access(&req); 590 if (denied || lflag) { 591 sp = getservbyport(sep->se_ctrladdr_in.sin_port, 592 sep->se_proto); 593 if (sp == NULL) { 594 (void)snprintf(buf, sizeof buf, "%d", 595 ntohs(sep->se_ctrladdr_in.sin_port)); 596 service = buf; 597 } else 598 service = sp->s_name; 599 } 600 if (denied) { 601 syslog(deny_severity, 602 "refused connection from %.500s, service %s (%s)", 603 eval_client(&req), service, sep->se_proto); 604 goto reject; 605 } 606 if (lflag) { 607 syslog(allow_severity, 608 "connection from %.500s, service %s (%s)", 609 eval_client(&req), service, sep->se_proto); 610 } 611 } 612 #endif /* LIBWRAP */ 613 614 if (sep->se_bi) { 615 (*sep->se_bi->bi_fn)(ctrl, sep); 616 } else { 617 if ((pwd = getpwnam(sep->se_user)) == NULL) { 618 syslog(LOG_ERR, "%s/%s: %s: No such user", 619 sep->se_service, sep->se_proto, sep->se_user); 620 goto reject; 621 } 622 if (sep->se_group && 623 (grp = getgrnam(sep->se_group)) == NULL) { 624 syslog(LOG_ERR, "%s/%s: %s: No such group", 625 sep->se_service, sep->se_proto, sep->se_group); 626 goto reject; 627 } 628 if (pwd->pw_uid) { 629 if (sep->se_group) 630 pwd->pw_gid = grp->gr_gid; 631 if (setgid(pwd->pw_gid) < 0) { 632 syslog(LOG_ERR, 633 "%s/%s: can't set gid %d: %m", sep->se_service, 634 sep->se_proto, pwd->pw_gid); 635 goto reject; 636 } 637 (void) initgroups(pwd->pw_name, 638 pwd->pw_gid); 639 if (setuid(pwd->pw_uid) < 0) { 640 syslog(LOG_ERR, 641 "%s/%s: can't set uid %d: %m", sep->se_service, 642 sep->se_proto, pwd->pw_uid); 643 goto reject; 644 } 645 } else if (sep->se_group) { 646 (void) setgid((gid_t)grp->gr_gid); 647 } 648 if (debug) 649 fprintf(stderr, "%d execl %s\n", 650 getpid(), sep->se_server); 651 #ifdef MULOG 652 if (sep->se_log) 653 dolog(sep, ctrl); 654 #endif 655 /* Set our control descriptor to not close-on-exec... */ 656 if (fcntl(ctrl, F_SETFD, 0) < 0) 657 syslog(LOG_ERR, "fcntl (F_SETFD, 0): %m"); 658 /* ...and dup it to stdin, stdout, and stderr. */ 659 if (ctrl != 0) { 660 dup2(ctrl, 0); 661 close(ctrl); 662 ctrl = 0; 663 } 664 dup2(0, 1); 665 dup2(0, 2); 666 #ifdef RLIMIT_NOFILE 667 if (rlim_ofile.rlim_cur != rlim_ofile_cur && 668 setrlimit(RLIMIT_NOFILE, &rlim_ofile) < 0) 669 syslog(LOG_ERR, "setrlimit: %m"); 670 #endif 671 execv(sep->se_server, sep->se_argv); 672 syslog(LOG_ERR, "cannot execute %s: %m", sep->se_server); 673 reject: 674 if (sep->se_socktype != SOCK_STREAM) 675 recv(ctrl, buf, sizeof (buf), 0); 676 _exit(1); 677 } 678 } 679 680 void 681 reapchild(signo) 682 int signo; 683 { 684 int status; 685 pid_t pid; 686 struct servtab *sep; 687 688 for (;;) { 689 pid = wait3(&status, WNOHANG, (struct rusage *)0); 690 if (pid <= 0) 691 break; 692 if (debug) 693 fprintf(stderr, "%d reaped, status %#x\n", 694 pid, status); 695 for (sep = servtab; sep; sep = sep->se_next) 696 if (sep->se_wait == pid) { 697 if (WIFEXITED(status) && WEXITSTATUS(status)) 698 syslog(LOG_WARNING, 699 "%s: exit status 0x%x", 700 sep->se_server, WEXITSTATUS(status)); 701 else if (WIFSIGNALED(status)) 702 syslog(LOG_WARNING, 703 "%s: exit signal 0x%x", 704 sep->se_server, WTERMSIG(status)); 705 sep->se_wait = 1; 706 FD_SET(sep->se_fd, &allsock); 707 nsock++; 708 if (debug) 709 fprintf(stderr, "restored %s, fd %d\n", 710 sep->se_service, sep->se_fd); 711 } 712 } 713 } 714 715 void 716 config(signo) 717 int signo; 718 { 719 struct servtab *sep, *cp, **sepp; 720 long omask; 721 int n; 722 723 if (!setconfig()) { 724 syslog(LOG_ERR, "%s: %m", CONFIG); 725 return; 726 } 727 for (sep = servtab; sep; sep = sep->se_next) 728 sep->se_checked = 0; 729 while ((cp = getconfigent())) { 730 for (sep = servtab; sep; sep = sep->se_next) 731 if (strcmp(sep->se_service, cp->se_service) == 0 && 732 strcmp(sep->se_hostaddr, cp->se_hostaddr) == 0 && 733 strcmp(sep->se_proto, cp->se_proto) == 0 && 734 ISMUX(sep) == ISMUX(cp)) 735 break; 736 if (sep != 0) { 737 int i; 738 739 #define SWAP(type, a, b) {type c=(type)a; (type)a=(type)b; (type)b=(type)c;} 740 741 omask = sigblock(SIGBLOCK); 742 /* 743 * sep->se_wait may be holding the pid of a daemon 744 * that we're waiting for. If so, don't overwrite 745 * it unless the config file explicitly says don't 746 * wait. 747 */ 748 if (cp->se_bi == 0 && 749 (sep->se_wait == 1 || cp->se_wait == 0)) 750 sep->se_wait = cp->se_wait; 751 SWAP(char *, sep->se_user, cp->se_user); 752 SWAP(char *, sep->se_group, cp->se_group); 753 SWAP(char *, sep->se_server, cp->se_server); 754 for (i = 0; i < MAXARGV; i++) 755 SWAP(char *, sep->se_argv[i], cp->se_argv[i]); 756 SWAP(int, cp->se_type, sep->se_type); 757 SWAP(int, cp->se_max, sep->se_max); 758 #undef SWAP 759 if (isrpcservice(sep)) 760 unregister_rpc(sep); 761 sep->se_rpcversl = cp->se_rpcversl; 762 sep->se_rpcversh = cp->se_rpcversh; 763 sigsetmask(omask); 764 freeconfig(cp); 765 if (debug) 766 print_service("REDO", sep); 767 } else { 768 sep = enter(cp); 769 if (debug) 770 print_service("ADD ", sep); 771 } 772 sep->se_checked = 1; 773 774 switch (sep->se_family) { 775 case AF_UNIX: 776 if (sep->se_fd != -1) 777 break; 778 n = strlen(sep->se_service); 779 if (n > sizeof(sep->se_ctrladdr_un.sun_path)) { 780 syslog(LOG_ERR, "%s: address too long", 781 sep->se_service); 782 sep->se_checked = 0; 783 continue; 784 } 785 (void)unlink(sep->se_service); 786 strncpy(sep->se_ctrladdr_un.sun_path, 787 sep->se_service, n); 788 sep->se_ctrladdr_un.sun_family = AF_UNIX; 789 sep->se_ctrladdr_size = n + 790 sizeof(sep->se_ctrladdr_un) - 791 sizeof(sep->se_ctrladdr_un.sun_path); 792 if (!ISMUX(sep)) 793 setup(sep); 794 break; 795 case AF_INET: 796 sep->se_ctrladdr_in.sin_family = AF_INET; 797 if (!strcmp(sep->se_hostaddr,"*")) 798 sep->se_ctrladdr_in.sin_addr.s_addr = 799 INADDR_ANY; 800 else if (!inet_aton(sep->se_hostaddr, 801 &sep->se_ctrladdr_in.sin_addr)) { 802 /* Do we really want to support hostname lookups here? */ 803 struct hostent *hp; 804 hp = gethostbyname(sep->se_hostaddr); 805 if (hp == 0) { 806 syslog(LOG_ERR, "%s: unknown host", 807 sep->se_hostaddr); 808 sep->se_checked = 0; 809 continue; 810 } else if (hp->h_addrtype != AF_INET) { 811 syslog(LOG_ERR, 812 "%s: address isn't an Internet address", 813 sep->se_hostaddr); 814 sep->se_checked = 0; 815 continue; 816 } else if (hp->h_length != sizeof(struct in_addr)) { 817 syslog(LOG_ERR, 818 "%s: address size wrong (under DNS corruption attack?)", 819 sep->se_hostaddr); 820 sep->se_checked = 0; 821 continue; 822 } else { 823 memcpy(&sep->se_ctrladdr_in.sin_addr, 824 hp->h_addr_list[0], 825 sizeof(struct in_addr)); 826 } 827 } 828 if (ISMUX(sep)) { 829 sep->se_fd = -1; 830 continue; 831 } 832 sep->se_ctrladdr_size = sizeof(sep->se_ctrladdr_in); 833 if (isrpcservice(sep)) { 834 struct rpcent *rp; 835 836 sep->se_rpcprog = atoi(sep->se_service); 837 if (sep->se_rpcprog == 0) { 838 rp = getrpcbyname(sep->se_service); 839 if (rp == 0) { 840 syslog(LOG_ERR, 841 "%s/%s: unknown service", 842 sep->se_service, 843 sep->se_proto); 844 sep->se_checked = 0; 845 continue; 846 } 847 sep->se_rpcprog = rp->r_number; 848 } 849 if (sep->se_fd == -1 && !ISMUX(sep)) 850 setup(sep); 851 if (sep->se_fd != -1) 852 register_rpc(sep); 853 } else { 854 u_short port = htons(atoi(sep->se_service)); 855 856 if (!port) { 857 sp = getservbyname(sep->se_service, 858 sep->se_proto); 859 if (sp == 0) { 860 syslog(LOG_ERR, 861 "%s/%s: unknown service", 862 sep->se_service, 863 sep->se_proto); 864 sep->se_checked = 0; 865 continue; 866 } 867 port = sp->s_port; 868 } 869 if (port != sep->se_ctrladdr_in.sin_port) { 870 sep->se_ctrladdr_in.sin_port = port; 871 if (sep->se_fd >= 0) 872 close_sep(sep); 873 } 874 if (sep->se_fd == -1 && !ISMUX(sep)) 875 setup(sep); 876 } 877 } 878 } 879 endconfig(); 880 /* 881 * Purge anything not looked at above. 882 */ 883 omask = sigblock(SIGBLOCK); 884 sepp = &servtab; 885 while ((sep = *sepp)) { 886 if (sep->se_checked) { 887 sepp = &sep->se_next; 888 continue; 889 } 890 *sepp = sep->se_next; 891 if (sep->se_fd >= 0) 892 close_sep(sep); 893 if (isrpcservice(sep)) 894 unregister_rpc(sep); 895 if (sep->se_family == AF_UNIX) 896 (void)unlink(sep->se_service); 897 if (debug) 898 print_service("FREE", sep); 899 freeconfig(sep); 900 free((char *)sep); 901 } 902 (void) sigsetmask(omask); 903 } 904 905 void 906 retry(signo) 907 int signo; 908 { 909 struct servtab *sep; 910 911 timingout = 0; 912 for (sep = servtab; sep; sep = sep->se_next) { 913 if (sep->se_fd == -1 && !ISMUX(sep)) { 914 switch (sep->se_family) { 915 case AF_UNIX: 916 case AF_INET: 917 setup(sep); 918 if (sep->se_fd != -1 && isrpcservice(sep)) 919 register_rpc(sep); 920 break; 921 } 922 } 923 } 924 } 925 926 void 927 goaway(signo) 928 int signo; 929 { 930 struct servtab *sep; 931 932 for (sep = servtab; sep; sep = sep->se_next) { 933 if (sep->se_fd == -1) 934 continue; 935 936 switch (sep->se_family) { 937 case AF_UNIX: 938 (void)unlink(sep->se_service); 939 break; 940 case AF_INET: 941 if (sep->se_wait == 1 && isrpcservice(sep)) 942 unregister_rpc(sep); 943 break; 944 } 945 (void)close(sep->se_fd); 946 } 947 (void)unlink(_PATH_INETDPID); 948 exit(0); 949 } 950 951 void 952 setup(sep) 953 struct servtab *sep; 954 { 955 int on = 1; 956 957 if ((sep->se_fd = socket(sep->se_family, sep->se_socktype, 0)) < 0) { 958 if (debug) 959 fprintf(stderr, "socket failed on %s/%s: %s\n", 960 sep->se_service, sep->se_proto, strerror(errno)); 961 syslog(LOG_ERR, "%s/%s: socket: %m", 962 sep->se_service, sep->se_proto); 963 return; 964 } 965 /* Set all listening sockets to close-on-exec. */ 966 if (fcntl(sep->se_fd, F_SETFD, FD_CLOEXEC) < 0) 967 syslog(LOG_ERR, "fcntl (F_SETFD, FD_CLOEXEC): %m"); 968 #define turnon(fd, opt) \ 969 setsockopt(fd, SOL_SOCKET, opt, (char *)&on, sizeof (on)) 970 if (strcmp(sep->se_proto, "tcp") == 0 && (options & SO_DEBUG) && 971 turnon(sep->se_fd, SO_DEBUG) < 0) 972 syslog(LOG_ERR, "setsockopt (SO_DEBUG): %m"); 973 if (turnon(sep->se_fd, SO_REUSEADDR) < 0) 974 syslog(LOG_ERR, "setsockopt (SO_REUSEADDR): %m"); 975 #undef turnon 976 if (bind(sep->se_fd, &sep->se_ctrladdr, sep->se_ctrladdr_size) < 0) { 977 if (debug) 978 fprintf(stderr, "bind failed on %s/%s: %s\n", 979 sep->se_service, sep->se_proto, strerror(errno)); 980 syslog(LOG_ERR, "%s/%s: bind: %m", 981 sep->se_service, sep->se_proto); 982 (void) close(sep->se_fd); 983 sep->se_fd = -1; 984 if (!timingout) { 985 timingout = 1; 986 alarm(RETRYTIME); 987 } 988 return; 989 } 990 if (sep->se_socktype == SOCK_STREAM) 991 listen(sep->se_fd, 10); 992 993 FD_SET(sep->se_fd, &allsock); 994 nsock++; 995 if (sep->se_fd > maxsock) { 996 maxsock = sep->se_fd; 997 if (maxsock > rlim_ofile_cur - FD_MARGIN) 998 bump_nofile(); 999 } 1000 if (debug) 1001 fprintf(stderr, "registered %s on %d\n", 1002 sep->se_server, sep->se_fd); 1003 } 1004 1005 /* 1006 * Finish with a service and its socket. 1007 */ 1008 void 1009 close_sep(sep) 1010 struct servtab *sep; 1011 { 1012 if (sep->se_fd >= 0) { 1013 nsock--; 1014 FD_CLR(sep->se_fd, &allsock); 1015 (void) close(sep->se_fd); 1016 sep->se_fd = -1; 1017 } 1018 sep->se_count = 0; 1019 /* 1020 * Don't keep the pid of this running deamon: when reapchild() 1021 * reaps this pid, it would erroneously increment nsock. 1022 */ 1023 if (sep->se_wait > 1) 1024 sep->se_wait = 1; 1025 } 1026 1027 void 1028 register_rpc(sep) 1029 struct servtab *sep; 1030 { 1031 #ifdef RPC 1032 int n; 1033 struct sockaddr_in sin; 1034 struct protoent *pp; 1035 1036 if ((pp = getprotobyname(sep->se_proto+4)) == NULL) { 1037 syslog(LOG_ERR, "%s: getproto: %m", 1038 sep->se_proto); 1039 return; 1040 } 1041 n = sizeof sin; 1042 if (getsockname(sep->se_fd, (struct sockaddr *)&sin, &n) < 0) { 1043 syslog(LOG_ERR, "%s/%s: getsockname: %m", 1044 sep->se_service, sep->se_proto); 1045 return; 1046 } 1047 1048 for (n = sep->se_rpcversl; n <= sep->se_rpcversh; n++) { 1049 if (debug) 1050 fprintf(stderr, "pmap_set: %u %u %u %u\n", 1051 sep->se_rpcprog, n, pp->p_proto, 1052 ntohs(sin.sin_port)); 1053 (void)pmap_unset(sep->se_rpcprog, n); 1054 if (!pmap_set(sep->se_rpcprog, n, pp->p_proto, ntohs(sin.sin_port))) 1055 syslog(LOG_ERR, "pmap_set: %u %u %u %u: %m", 1056 sep->se_rpcprog, n, pp->p_proto, 1057 ntohs(sin.sin_port)); 1058 } 1059 #endif /* RPC */ 1060 } 1061 1062 void 1063 unregister_rpc(sep) 1064 struct servtab *sep; 1065 { 1066 #ifdef RPC 1067 int n; 1068 1069 for (n = sep->se_rpcversl; n <= sep->se_rpcversh; n++) { 1070 if (debug) 1071 fprintf(stderr, "pmap_unset(%u, %u)\n", 1072 sep->se_rpcprog, n); 1073 if (!pmap_unset(sep->se_rpcprog, n)) 1074 syslog(LOG_ERR, "pmap_unset(%u, %u)\n", 1075 sep->se_rpcprog, n); 1076 } 1077 #endif /* RPC */ 1078 } 1079 1080 1081 struct servtab * 1082 enter(cp) 1083 struct servtab *cp; 1084 { 1085 struct servtab *sep; 1086 long omask; 1087 1088 sep = (struct servtab *)malloc(sizeof (*sep)); 1089 if (sep == (struct servtab *)0) { 1090 syslog(LOG_ERR, "Out of memory."); 1091 exit(-1); 1092 } 1093 *sep = *cp; 1094 sep->se_fd = -1; 1095 sep->se_rpcprog = -1; 1096 omask = sigblock(SIGBLOCK); 1097 sep->se_next = servtab; 1098 servtab = sep; 1099 sigsetmask(omask); 1100 return (sep); 1101 } 1102 1103 FILE *fconfig = NULL; 1104 struct servtab serv; 1105 char line[LINE_MAX]; 1106 char *defhost; 1107 1108 int 1109 setconfig() 1110 { 1111 if (defhost) free(defhost); 1112 defhost = newstr("*"); 1113 if (fconfig != NULL) { 1114 fseek(fconfig, 0L, SEEK_SET); 1115 return (1); 1116 } 1117 fconfig = fopen(CONFIG, "r"); 1118 return (fconfig != NULL); 1119 } 1120 1121 void 1122 endconfig() 1123 { 1124 if (fconfig) { 1125 (void) fclose(fconfig); 1126 fconfig = NULL; 1127 } 1128 if (defhost) { 1129 free(defhost); 1130 defhost = 0; 1131 } 1132 } 1133 1134 struct servtab * 1135 getconfigent() 1136 { 1137 struct servtab *sep = &serv; 1138 int argc; 1139 char *cp, *arg; 1140 static char TCPMUX_TOKEN[] = "tcpmux/"; 1141 #define MUX_LEN (sizeof(TCPMUX_TOKEN)-1) 1142 char *hostdelim; 1143 1144 more: 1145 #ifdef MULOG 1146 while ((cp = nextline(fconfig)) && (*cp == '#' || *cp == '\0')) { 1147 /* Avoid use of `skip' if there is a danger of it looking 1148 * at continuation lines. 1149 */ 1150 do { 1151 cp++; 1152 } while (*cp == ' ' || *cp == '\t'); 1153 if (*cp == '\0') 1154 continue; 1155 if ((arg = skip(&cp)) == NULL) 1156 continue; 1157 if (strcmp(arg, "DOMAIN")) 1158 continue; 1159 if (curdom) 1160 free(curdom); 1161 curdom = NULL; 1162 while (*cp == ' ' || *cp == '\t') 1163 cp++; 1164 if (*cp == '\0') 1165 continue; 1166 arg = cp; 1167 while (*cp && *cp != ' ' && *cp != '\t') 1168 cp++; 1169 if (*cp != '\0') 1170 *cp++ = '\0'; 1171 curdom = newstr(arg); 1172 } 1173 #else 1174 while ((cp = nextline(fconfig)) && (*cp == '#' || *cp == '\0')) 1175 ; 1176 #endif 1177 if (cp == NULL) 1178 return ((struct servtab *)0); 1179 /* 1180 * clear the static buffer, since some fields (se_ctrladdr, 1181 * for example) don't get initialized here. 1182 */ 1183 memset((caddr_t)sep, 0, sizeof *sep); 1184 arg = skip(&cp); 1185 if (cp == NULL) { 1186 /* got an empty line containing just blanks/tabs. */ 1187 goto more; 1188 } 1189 /* Check for a host name. */ 1190 hostdelim = strrchr(arg, ':'); 1191 if (hostdelim) { 1192 *hostdelim = '\0'; 1193 sep->se_hostaddr = newstr(arg); 1194 arg = hostdelim + 1; 1195 /* 1196 * If the line is of the form `host:', then just change the 1197 * default host for the following lines. 1198 */ 1199 if (*arg == '\0') { 1200 arg = skip(&cp); 1201 if (cp == NULL) { 1202 free(defhost); 1203 defhost = sep->se_hostaddr; 1204 goto more; 1205 } 1206 } 1207 } else 1208 sep->se_hostaddr = newstr(defhost); 1209 if (strncmp(arg, TCPMUX_TOKEN, MUX_LEN) == 0) { 1210 char *c = arg + MUX_LEN; 1211 if (*c == '+') { 1212 sep->se_type = MUXPLUS_TYPE; 1213 c++; 1214 } else 1215 sep->se_type = MUX_TYPE; 1216 sep->se_service = newstr(c); 1217 } else { 1218 sep->se_service = newstr(arg); 1219 sep->se_type = NORM_TYPE; 1220 } 1221 1222 arg = sskip(&cp); 1223 if (strcmp(arg, "stream") == 0) 1224 sep->se_socktype = SOCK_STREAM; 1225 else if (strcmp(arg, "dgram") == 0) 1226 sep->se_socktype = SOCK_DGRAM; 1227 else if (strcmp(arg, "rdm") == 0) 1228 sep->se_socktype = SOCK_RDM; 1229 else if (strcmp(arg, "seqpacket") == 0) 1230 sep->se_socktype = SOCK_SEQPACKET; 1231 else if (strcmp(arg, "raw") == 0) 1232 sep->se_socktype = SOCK_RAW; 1233 else 1234 sep->se_socktype = -1; 1235 1236 sep->se_proto = newstr(sskip(&cp)); 1237 if (strcmp(sep->se_proto, "unix") == 0) { 1238 sep->se_family = AF_UNIX; 1239 } else { 1240 sep->se_family = AF_INET; 1241 if (strncmp(sep->se_proto, "rpc/", 4) == 0) { 1242 #ifdef RPC 1243 char *cp, *ccp; 1244 cp = strchr(sep->se_service, '/'); 1245 if (cp == 0) { 1246 syslog(LOG_ERR, "%s: no rpc version", 1247 sep->se_service); 1248 goto more; 1249 } 1250 *cp++ = '\0'; 1251 sep->se_rpcversl = sep->se_rpcversh = 1252 strtol(cp, &ccp, 0); 1253 if (ccp == cp) { 1254 badafterall: 1255 syslog(LOG_ERR, "%s/%s: bad rpc version", 1256 sep->se_service, cp); 1257 goto more; 1258 } 1259 if (*ccp == '-') { 1260 cp = ccp + 1; 1261 sep->se_rpcversh = strtol(cp, &ccp, 0); 1262 if (ccp == cp) 1263 goto badafterall; 1264 } 1265 #else 1266 syslog(LOG_ERR, "%s: rpc services not suported", 1267 sep->se_service); 1268 goto more; 1269 #endif /* RPC */ 1270 } 1271 } 1272 arg = sskip(&cp); 1273 { 1274 char *cp; 1275 cp = strchr(arg, '.'); 1276 if (cp) { 1277 *cp++ = '\0'; 1278 sep->se_max = atoi(cp); 1279 } else 1280 sep->se_max = TOOMANY; 1281 } 1282 sep->se_wait = strcmp(arg, "wait") == 0; 1283 if (ISMUX(sep)) { 1284 /* 1285 * Silently enforce "nowait" for TCPMUX services since 1286 * they don't have an assigned port to listen on. 1287 */ 1288 sep->se_wait = 0; 1289 1290 if (strcmp(sep->se_proto, "tcp")) { 1291 syslog(LOG_ERR, 1292 "%s: bad protocol for tcpmux service %s", 1293 CONFIG, sep->se_service); 1294 goto more; 1295 } 1296 if (sep->se_socktype != SOCK_STREAM) { 1297 syslog(LOG_ERR, 1298 "%s: bad socket type for tcpmux service %s", 1299 CONFIG, sep->se_service); 1300 goto more; 1301 } 1302 } 1303 sep->se_user = newstr(sskip(&cp)); 1304 if ((sep->se_group = strchr(sep->se_user, '.'))) 1305 *sep->se_group++ = '\0'; 1306 sep->se_server = newstr(sskip(&cp)); 1307 if (strcmp(sep->se_server, "internal") == 0) { 1308 struct biltin *bi; 1309 1310 for (bi = biltins; bi->bi_service; bi++) 1311 if (bi->bi_socktype == sep->se_socktype && 1312 strcmp(bi->bi_service, sep->se_service) == 0) 1313 break; 1314 if (bi->bi_service == 0) { 1315 syslog(LOG_ERR, "internal service %s unknown", 1316 sep->se_service); 1317 goto more; 1318 } 1319 sep->se_bi = bi; 1320 sep->se_wait = bi->bi_wait; 1321 } else 1322 sep->se_bi = NULL; 1323 argc = 0; 1324 for (arg = skip(&cp); cp; arg = skip(&cp)) { 1325 #if MULOG 1326 char *colon; 1327 1328 if (argc == 0 && (colon = strrchr(arg, ':'))) { 1329 while (arg < colon) { 1330 int x; 1331 char *ccp; 1332 1333 switch (*arg++) { 1334 case 'l': 1335 x = 1; 1336 if (isdigit(*arg)) { 1337 x = strtol(arg, &ccp, 0); 1338 if (ccp == arg) 1339 break; 1340 arg = ccp; 1341 } 1342 sep->se_log &= ~MULOG_RFC931; 1343 sep->se_log |= x; 1344 break; 1345 case 'a': 1346 sep->se_log |= MULOG_RFC931; 1347 break; 1348 default: 1349 break; 1350 } 1351 } 1352 arg = colon + 1; 1353 } 1354 #endif 1355 if (argc < MAXARGV) 1356 sep->se_argv[argc++] = newstr(arg); 1357 } 1358 while (argc <= MAXARGV) 1359 sep->se_argv[argc++] = NULL; 1360 return (sep); 1361 } 1362 1363 void 1364 freeconfig(cp) 1365 struct servtab *cp; 1366 { 1367 int i; 1368 1369 if (cp->se_hostaddr) 1370 free(cp->se_hostaddr); 1371 if (cp->se_service) 1372 free(cp->se_service); 1373 if (cp->se_proto) 1374 free(cp->se_proto); 1375 if (cp->se_user) 1376 free(cp->se_user); 1377 /* Note: se_group is part of the newstr'ed se_user */ 1378 if (cp->se_server) 1379 free(cp->se_server); 1380 for (i = 0; i < MAXARGV; i++) 1381 if (cp->se_argv[i]) 1382 free(cp->se_argv[i]); 1383 } 1384 1385 1386 /* 1387 * Safe skip - if skip returns null, log a syntax error in the 1388 * configuration file and exit. 1389 */ 1390 char * 1391 sskip(cpp) 1392 char **cpp; 1393 { 1394 char *cp; 1395 1396 cp = skip(cpp); 1397 if (cp == NULL) { 1398 syslog(LOG_ERR, "%s: syntax error", CONFIG); 1399 exit(-1); 1400 } 1401 return (cp); 1402 } 1403 1404 char * 1405 skip(cpp) 1406 char **cpp; 1407 { 1408 char *cp = *cpp; 1409 char *start; 1410 1411 if (*cpp == NULL) 1412 return ((char *)0); 1413 1414 again: 1415 while (*cp == ' ' || *cp == '\t') 1416 cp++; 1417 if (*cp == '\0') { 1418 int c; 1419 1420 c = getc(fconfig); 1421 (void) ungetc(c, fconfig); 1422 if (c == ' ' || c == '\t') 1423 if ((cp = nextline(fconfig))) 1424 goto again; 1425 *cpp = (char *)0; 1426 return ((char *)0); 1427 } 1428 start = cp; 1429 while (*cp && *cp != ' ' && *cp != '\t') 1430 cp++; 1431 if (*cp != '\0') 1432 *cp++ = '\0'; 1433 *cpp = cp; 1434 return (start); 1435 } 1436 1437 char * 1438 nextline(fd) 1439 FILE *fd; 1440 { 1441 char *cp; 1442 1443 if (fgets(line, sizeof (line), fd) == NULL) 1444 return ((char *)0); 1445 cp = strchr(line, '\n'); 1446 if (cp) 1447 *cp = '\0'; 1448 return (line); 1449 } 1450 1451 char * 1452 newstr(cp) 1453 char *cp; 1454 { 1455 if ((cp = strdup(cp ? cp : ""))) 1456 return (cp); 1457 syslog(LOG_ERR, "strdup: %m"); 1458 exit(-1); 1459 } 1460 1461 void 1462 inetd_setproctitle(a, s) 1463 char *a; 1464 int s; 1465 { 1466 int size; 1467 char *cp; 1468 struct sockaddr_in sin; 1469 char buf[80]; 1470 1471 cp = Argv[0]; 1472 size = sizeof(sin); 1473 if (getpeername(s, (struct sockaddr *)&sin, &size) == 0) 1474 (void)snprintf(buf, sizeof buf, "-%s [%s]", a, 1475 inet_ntoa(sin.sin_addr)); 1476 else 1477 (void)snprintf(buf, sizeof buf, "-%s", a); 1478 strncpy(cp, buf, LastArg - cp); 1479 cp += strlen(cp); 1480 while (cp < LastArg) 1481 *cp++ = ' '; 1482 } 1483 1484 void 1485 logpid() 1486 { 1487 FILE *fp; 1488 1489 if ((fp = fopen(_PATH_INETDPID, "w")) != NULL) { 1490 fprintf(fp, "%u\n", getpid()); 1491 (void)fclose(fp); 1492 } 1493 } 1494 1495 void 1496 bump_nofile() 1497 { 1498 #ifdef RLIMIT_NOFILE 1499 1500 #define FD_CHUNK 32 1501 1502 struct rlimit rl; 1503 1504 if (getrlimit(RLIMIT_NOFILE, &rl) < 0) { 1505 syslog(LOG_ERR, "getrlimit: %m"); 1506 return; 1507 } 1508 rl.rlim_cur = MIN(rl.rlim_max, rl.rlim_cur + FD_CHUNK); 1509 if (rl.rlim_cur <= rlim_ofile_cur) { 1510 syslog(LOG_ERR, 1511 "bump_nofile: cannot extend file limit, max = %d", 1512 (int)rl.rlim_cur); 1513 return; 1514 } 1515 1516 if (setrlimit(RLIMIT_NOFILE, &rl) < 0) { 1517 syslog(LOG_ERR, "setrlimit: %m"); 1518 return; 1519 } 1520 1521 rlim_ofile_cur = rl.rlim_cur; 1522 return; 1523 1524 #else 1525 syslog(LOG_ERR, "bump_nofile: cannot extend file limit"); 1526 return; 1527 #endif 1528 } 1529 1530 /* 1531 * Internet services provided internally by inetd: 1532 */ 1533 #define BUFSIZE 4096 1534 1535 /* ARGSUSED */ 1536 void 1537 echo_stream(s, sep) /* Echo service -- echo data back */ 1538 int s; 1539 struct servtab *sep; 1540 { 1541 char buffer[BUFSIZE]; 1542 int i; 1543 1544 inetd_setproctitle(sep->se_service, s); 1545 while ((i = read(s, buffer, sizeof(buffer))) > 0 && 1546 write(s, buffer, i) > 0) 1547 ; 1548 } 1549 1550 /* ARGSUSED */ 1551 void 1552 echo_dg(s, sep) /* Echo service -- echo data back */ 1553 int s; 1554 struct servtab *sep; 1555 { 1556 char buffer[BUFSIZE]; 1557 int i, size; 1558 struct sockaddr sa; 1559 1560 size = sizeof(sa); 1561 if ((i = recvfrom(s, buffer, sizeof(buffer), 0, &sa, &size)) < 0) 1562 return; 1563 (void) sendto(s, buffer, i, 0, &sa, sizeof(sa)); 1564 } 1565 1566 /* ARGSUSED */ 1567 void 1568 discard_stream(s, sep) /* Discard service -- ignore data */ 1569 int s; 1570 struct servtab *sep; 1571 { 1572 char buffer[BUFSIZE]; 1573 1574 inetd_setproctitle(sep->se_service, s); 1575 while ((errno = 0, read(s, buffer, sizeof(buffer)) > 0) || 1576 errno == EINTR) 1577 ; 1578 } 1579 1580 /* ARGSUSED */ 1581 void 1582 discard_dg(s, sep) /* Discard service -- ignore data */ 1583 int s; 1584 struct servtab *sep; 1585 { 1586 char buffer[BUFSIZE]; 1587 1588 (void) read(s, buffer, sizeof(buffer)); 1589 } 1590 1591 #include <ctype.h> 1592 #define LINESIZ 72 1593 char ring[128]; 1594 char *endring; 1595 1596 void 1597 initring() 1598 { 1599 int i; 1600 1601 endring = ring; 1602 1603 for (i = 0; i <= 128; ++i) 1604 if (isprint(i)) 1605 *endring++ = i; 1606 } 1607 1608 /* ARGSUSED */ 1609 void 1610 chargen_stream(s, sep) /* Character generator */ 1611 int s; 1612 struct servtab *sep; 1613 { 1614 int len; 1615 char *rs, text[LINESIZ+2]; 1616 1617 inetd_setproctitle(sep->se_service, s); 1618 1619 if (!endring) { 1620 initring(); 1621 rs = ring; 1622 } 1623 1624 text[LINESIZ] = '\r'; 1625 text[LINESIZ + 1] = '\n'; 1626 for (rs = ring;;) { 1627 if ((len = endring - rs) >= LINESIZ) 1628 memmove(text, rs, LINESIZ); 1629 else { 1630 memmove(text, rs, len); 1631 memmove(text + len, ring, LINESIZ - len); 1632 } 1633 if (++rs == endring) 1634 rs = ring; 1635 if (write(s, text, sizeof(text)) != sizeof(text)) 1636 break; 1637 } 1638 } 1639 1640 /* ARGSUSED */ 1641 void 1642 chargen_dg(s, sep) /* Character generator */ 1643 int s; 1644 struct servtab *sep; 1645 { 1646 struct sockaddr sa; 1647 static char *rs; 1648 int len, size; 1649 char text[LINESIZ+2]; 1650 1651 if (endring == 0) { 1652 initring(); 1653 rs = ring; 1654 } 1655 1656 size = sizeof(sa); 1657 if (recvfrom(s, text, sizeof(text), 0, &sa, &size) < 0) 1658 return; 1659 1660 if ((len = endring - rs) >= LINESIZ) 1661 memmove(text, rs, LINESIZ); 1662 else { 1663 memmove(text, rs, len); 1664 memmove(text + len, ring, LINESIZ - len); 1665 } 1666 if (++rs == endring) 1667 rs = ring; 1668 text[LINESIZ] = '\r'; 1669 text[LINESIZ + 1] = '\n'; 1670 (void) sendto(s, text, sizeof(text), 0, &sa, sizeof(sa)); 1671 } 1672 1673 /* 1674 * Return a machine readable date and time, in the form of the 1675 * number of seconds since midnight, Jan 1, 1900. Since gettimeofday 1676 * returns the number of seconds since midnight, Jan 1, 1970, 1677 * we must add 2208988800 seconds to this figure to make up for 1678 * some seventy years Bell Labs was asleep. 1679 */ 1680 1681 long 1682 machtime() 1683 { 1684 struct timeval tv; 1685 1686 if (gettimeofday(&tv, (struct timezone *)0) < 0) { 1687 if (debug) 1688 fprintf(stderr, "Unable to get time of day\n"); 1689 return (0L); 1690 } 1691 #define OFFSET ((u_long)25567 * 24*60*60) 1692 return (htonl((long)(tv.tv_sec + OFFSET))); 1693 #undef OFFSET 1694 } 1695 1696 /* ARGSUSED */ 1697 void 1698 machtime_stream(s, sep) 1699 int s; 1700 struct servtab *sep; 1701 { 1702 long result; 1703 1704 result = machtime(); 1705 (void) write(s, (char *) &result, sizeof(result)); 1706 } 1707 1708 /* ARGSUSED */ 1709 void 1710 machtime_dg(s, sep) 1711 int s; 1712 struct servtab *sep; 1713 { 1714 long result; 1715 struct sockaddr sa; 1716 int size; 1717 1718 size = sizeof(sa); 1719 if (recvfrom(s, (char *)&result, sizeof(result), 0, &sa, &size) < 0) 1720 return; 1721 result = machtime(); 1722 (void) sendto(s, (char *) &result, sizeof(result), 0, &sa, sizeof(sa)); 1723 } 1724 1725 /* ARGSUSED */ 1726 void 1727 daytime_stream(s, sep) /* Return human-readable time of day */ 1728 int s; 1729 struct servtab *sep; 1730 { 1731 char buffer[256]; 1732 time_t clock; 1733 int len; 1734 1735 clock = time((time_t *) 0); 1736 1737 len = snprintf(buffer, sizeof buffer, "%.24s\r\n", ctime(&clock)); 1738 (void) write(s, buffer, len); 1739 } 1740 1741 /* ARGSUSED */ 1742 void 1743 daytime_dg(s, sep) /* Return human-readable time of day */ 1744 int s; 1745 struct servtab *sep; 1746 { 1747 char buffer[256]; 1748 time_t clock; 1749 struct sockaddr sa; 1750 int size, len; 1751 1752 clock = time((time_t *) 0); 1753 1754 size = sizeof(sa); 1755 if (recvfrom(s, buffer, sizeof(buffer), 0, &sa, &size) < 0) 1756 return; 1757 len = snprintf(buffer, sizeof buffer, "%.24s\r\n", ctime(&clock)); 1758 (void) sendto(s, buffer, len, 0, &sa, sizeof(sa)); 1759 } 1760 1761 /* 1762 * print_service: 1763 * Dump relevant information to stderr 1764 */ 1765 void 1766 print_service(action, sep) 1767 char *action; 1768 struct servtab *sep; 1769 { 1770 if (isrpcservice(sep)) 1771 fprintf(stderr, 1772 "%s: %s rpcprog=%d, rpcvers = %d/%d, proto=%s, wait.max=%d.%d, user.group=%s.%s builtin=%lx server=%s\n", 1773 action, sep->se_service, 1774 sep->se_rpcprog, sep->se_rpcversh, sep->se_rpcversl, sep->se_proto, 1775 sep->se_wait, sep->se_max, sep->se_user, sep->se_group, 1776 (long)sep->se_bi, sep->se_server); 1777 else 1778 fprintf(stderr, 1779 "%s: %s proto=%s, wait.max=%d.%d, user.group=%s.%s builtin=%lx server=%s\n", 1780 action, sep->se_service, sep->se_proto, 1781 sep->se_wait, sep->se_max, sep->se_user, sep->se_group, 1782 (long)sep->se_bi, sep->se_server); 1783 } 1784 1785 void 1786 usage() 1787 { 1788 1789 #ifdef LIBWRAP 1790 (void)fprintf(stderr, "usage: %s [-dl] [conf]\n", __progname); 1791 #else 1792 (void)fprintf(stderr, "usage: %s [-d] [conf]\n", __progname); 1793 #endif 1794 exit(1); 1795 } 1796 1797 1798 /* 1799 * Based on TCPMUX.C by Mark K. Lottor November 1988 1800 * sri-nic::ps:<mkl>tcpmux.c 1801 */ 1802 1803 static int /* # of characters upto \r,\n or \0 */ 1804 getline(fd, buf, len) 1805 int fd; 1806 char *buf; 1807 int len; 1808 { 1809 int count = 0, n; 1810 1811 do { 1812 n = read(fd, buf, len-count); 1813 if (n == 0) 1814 return (count); 1815 if (n < 0) 1816 return (-1); 1817 while (--n >= 0) { 1818 if (*buf == '\r' || *buf == '\n' || *buf == '\0') 1819 return (count); 1820 count++; 1821 buf++; 1822 } 1823 } while (count < len); 1824 return (count); 1825 } 1826 1827 #define MAX_SERV_LEN (256+2) /* 2 bytes for \r\n */ 1828 1829 #define strwrite(fd, buf) (void) write(fd, buf, sizeof(buf)-1) 1830 1831 void 1832 tcpmux(ctrl, sep) 1833 int ctrl; 1834 struct servtab *sep; 1835 { 1836 char service[MAX_SERV_LEN+1]; 1837 int len; 1838 1839 /* Get requested service name */ 1840 if ((len = getline(ctrl, service, MAX_SERV_LEN)) < 0) { 1841 strwrite(ctrl, "-Error reading service name\r\n"); 1842 goto reject; 1843 } 1844 service[len] = '\0'; 1845 1846 if (debug) 1847 fprintf(stderr, "tcpmux: someone wants %s\n", service); 1848 1849 /* 1850 * Help is a required command, and lists available services, 1851 * one per line. 1852 */ 1853 if (!strcasecmp(service, "help")) { 1854 strwrite(ctrl, "+Available services:\r\n"); 1855 strwrite(ctrl, "help\r\n"); 1856 for (sep = servtab; sep; sep = sep->se_next) { 1857 if (!ISMUX(sep)) 1858 continue; 1859 (void)write(ctrl, sep->se_service, 1860 strlen(sep->se_service)); 1861 strwrite(ctrl, "\r\n"); 1862 } 1863 goto reject; 1864 } 1865 1866 /* Try matching a service in inetd.conf with the request */ 1867 for (sep = servtab; sep; sep = sep->se_next) { 1868 if (!ISMUX(sep)) 1869 continue; 1870 if (!strcasecmp(service, sep->se_service)) { 1871 if (ISMUXPLUS(sep)) 1872 strwrite(ctrl, "+Go\r\n"); 1873 run_service(ctrl, sep); 1874 return; 1875 } 1876 } 1877 strwrite(ctrl, "-Service not available\r\n"); 1878 reject: 1879 _exit(1); 1880 } 1881 1882 1883 #ifdef MULOG 1884 dolog(sep, ctrl) 1885 struct servtab *sep; 1886 int ctrl; 1887 { 1888 struct sockaddr sa; 1889 struct sockaddr_in *sin = (struct sockaddr_in *)&sa; 1890 int len = sizeof(sa); 1891 struct hostent *hp; 1892 char *host, *dp, buf[BUFSIZ], *rfc931_name(); 1893 int connected = 1; 1894 1895 if (sep->se_family != AF_INET) 1896 return; 1897 1898 if (getpeername(ctrl, &sa, &len) < 0) { 1899 if (errno != ENOTCONN) { 1900 syslog(LOG_ERR, "getpeername: %m"); 1901 return; 1902 } 1903 if (recvfrom(ctrl, buf, sizeof(buf), MSG_PEEK, &sa, &len) < 0) { 1904 syslog(LOG_ERR, "recvfrom: %m"); 1905 return; 1906 } 1907 connected = 0; 1908 } 1909 if (sa.sa_family != AF_INET) { 1910 syslog(LOG_ERR, "unexpected address family %u", sa.sa_family); 1911 return; 1912 } 1913 1914 hp = gethostbyaddr((char *) &sin->sin_addr.s_addr, 1915 sizeof (sin->sin_addr.s_addr), AF_INET); 1916 1917 host = hp?hp->h_name:inet_ntoa(sin->sin_addr); 1918 1919 switch (sep->se_log & ~MULOG_RFC931) { 1920 case 0: 1921 return; 1922 case 1: 1923 if (curdom == NULL || *curdom == '\0') 1924 break; 1925 dp = host + strlen(host) - strlen(curdom); 1926 if (dp < host) 1927 break; 1928 if (debug) 1929 fprintf(stderr, "check \"%s\" against curdom \"%s\"\n", 1930 host, curdom); 1931 if (strcasecmp(dp, curdom) == 0) 1932 return; 1933 break; 1934 case 2: 1935 default: 1936 break; 1937 } 1938 1939 openlog("", LOG_NOWAIT, MULOG); 1940 1941 if (connected && (sep->se_log & MULOG_RFC931)) 1942 syslog(LOG_INFO, "%s@%s wants %s", 1943 rfc931_name(sin, ctrl), host, sep->se_service); 1944 else 1945 syslog(LOG_INFO, "%s wants %s", 1946 host, sep->se_service); 1947 } 1948 1949 /* 1950 * From tcp_log by 1951 * Wietse Venema, Eindhoven University of Technology, The Netherlands. 1952 */ 1953 #if 0 1954 static char sccsid[] = "@(#) rfc931.c 1.3 92/08/31 22:54:46"; 1955 #endif 1956 1957 #include <setjmp.h> 1958 1959 #define RFC931_PORT 113 /* Semi-well-known port */ 1960 #define TIMEOUT 4 1961 #define TIMEOUT2 10 1962 1963 static jmp_buf timebuf; 1964 1965 /* timeout - handle timeouts */ 1966 1967 static void timeout(sig) 1968 int sig; 1969 { 1970 longjmp(timebuf, sig); 1971 } 1972 1973 /* rfc931_name - return remote user name */ 1974 1975 char * 1976 rfc931_name(there, ctrl) 1977 struct sockaddr_in *there; /* remote link information */ 1978 int ctrl; 1979 { 1980 struct sockaddr_in here; /* local link information */ 1981 struct sockaddr_in sin; /* for talking to RFC931 daemon */ 1982 int length; 1983 int s; 1984 unsigned remote; 1985 unsigned local; 1986 static char user[256]; /* XXX */ 1987 char buf[256]; 1988 char *cp; 1989 char *result = "USER_UNKNOWN"; 1990 int len; 1991 1992 /* Find out local port number of our stdin. */ 1993 1994 length = sizeof(here); 1995 if (getsockname(ctrl, (struct sockaddr *) &here, &length) == -1) { 1996 syslog(LOG_ERR, "getsockname: %m"); 1997 return (result); 1998 } 1999 /* Set up timer so we won't get stuck. */ 2000 2001 if ((s = socket(AF_INET, SOCK_STREAM, 0)) == -1) { 2002 syslog(LOG_ERR, "socket: %m"); 2003 return (result); 2004 } 2005 2006 sin = here; 2007 sin.sin_port = htons(0); 2008 if (bind(s, (struct sockaddr *) &sin, sizeof(sin)) == -1) { 2009 syslog(LOG_ERR, "bind: %m"); 2010 return (result); 2011 } 2012 2013 signal(SIGALRM, timeout); 2014 if (setjmp(timebuf)) { 2015 close(s); /* not: fclose(fp) */ 2016 return (result); 2017 } 2018 alarm(TIMEOUT); 2019 2020 /* Connect to the RFC931 daemon. */ 2021 2022 sin = *there; 2023 sin.sin_port = htons(RFC931_PORT); 2024 if (connect(s, (struct sockaddr *) &sin, sizeof(sin)) == -1) { 2025 close(s); 2026 alarm(0); 2027 return (result); 2028 } 2029 2030 /* Query the RFC 931 server. Would 13-byte writes ever be broken up? */ 2031 (void)snprintf(buf, sizeof buf, "%u,%u\r\n", ntohs(there->sin_port), 2032 ntohs(here.sin_port)); 2033 2034 2035 for (len = 0, cp = buf; len < strlen(buf); ) { 2036 int n; 2037 2038 if ((n = write(s, cp, strlen(buf) - len)) == -1) { 2039 close(s); 2040 alarm(0); 2041 return (result); 2042 } 2043 cp += n; 2044 len += n; 2045 } 2046 2047 /* Read response */ 2048 for (cp = buf; cp < buf + sizeof(buf) - 1; ) { 2049 char c; 2050 if (read(s, &c, 1) != 1) { 2051 close(s); 2052 alarm(0); 2053 return (result); 2054 } 2055 if (c == '\n') 2056 break; 2057 *cp++ = c; 2058 } 2059 *cp = '\0'; 2060 2061 if (sscanf(buf, "%u , %u : USERID :%*[^:]:%255s", &remote, &local, user) == 3 2062 && ntohs(there->sin_port) == remote 2063 && ntohs(here.sin_port) == local) { 2064 2065 /* Strip trailing carriage return. */ 2066 if (cp = strchr(user, '\r')) 2067 *cp = 0; 2068 result = user; 2069 } 2070 2071 alarm(0); 2072 close(s); 2073 return (result); 2074 } 2075 #endif 2076
Indexes created Fri Sep 26 20:09:58 GMT 2025