inetd.c revision 1.40
1 /* $NetBSD: inetd.c,v 1.40 1998/01/20 16:44:22 christos 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 1.40 1998/01/20 16:44:22 christos 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_handler = SIG_IGN; 446 sigvec(SIGPIPE, &sv, (struct sigvec *)0); 447 448 { 449 /* space for daemons to overwrite environment for ps */ 450 #define DUMMYSIZE 100 451 char dummy[DUMMYSIZE]; 452 453 (void)memset(dummy, 'x', DUMMYSIZE - 1); 454 dummy[DUMMYSIZE - 1] = '\0'; 455 456 (void)setenv("inetd_dummy", dummy, 1); 457 } 458 459 for (;;) { 460 int n, ctrl; 461 fd_set readable; 462 463 if (nsock == 0) { 464 (void) sigblock(SIGBLOCK); 465 while (nsock == 0) 466 sigpause(0L); 467 (void) sigsetmask(0L); 468 } 469 readable = allsock; 470 if ((n = select(maxsock + 1, &readable, (fd_set *)0, 471 (fd_set *)0, (struct timeval *)0)) <= 0) { 472 if (n == -1 && errno != EINTR) { 473 syslog(LOG_WARNING, "select: %m"); 474 sleep(1); 475 } 476 continue; 477 } 478 for (sep = servtab; n && sep; sep = nsep) { 479 nsep = sep->se_next; 480 if (sep->se_fd != -1 && FD_ISSET(sep->se_fd, &readable)) { 481 n--; 482 if (debug) 483 fprintf(stderr, "someone wants %s\n", sep->se_service); 484 if (!sep->se_wait && sep->se_socktype == SOCK_STREAM) { 485 /* XXX here do the libwrap check-before-accept */ 486 ctrl = accept(sep->se_fd, (struct sockaddr *)0, 487 (int *)0); 488 if (debug) 489 fprintf(stderr, "accept, ctrl %d\n", ctrl); 490 if (ctrl < 0) { 491 if (errno != EINTR) 492 syslog(LOG_WARNING, 493 "accept (for %s): %m", 494 sep->se_service); 495 continue; 496 } 497 } else 498 ctrl = sep->se_fd; 499 (void) sigblock(SIGBLOCK); 500 pid = 0; 501 #ifdef LIBWRAP_INTERNAL 502 dofork = 1; 503 #else 504 dofork = (sep->se_bi == 0 || sep->se_bi->bi_fork); 505 #endif 506 if (dofork) { 507 if (sep->se_count++ == 0) 508 (void)gettimeofday(&sep->se_time, 509 (struct timezone *)0); 510 else if (sep->se_count >= sep->se_max) { 511 struct timeval now; 512 513 (void)gettimeofday(&now, (struct timezone *)0); 514 if (now.tv_sec - sep->se_time.tv_sec > 515 CNT_INTVL) { 516 sep->se_time = now; 517 sep->se_count = 1; 518 } else { 519 syslog(LOG_ERR, 520 "%s/%s server failing (looping), service terminated\n", 521 sep->se_service, sep->se_proto); 522 close_sep(sep); 523 sigsetmask(0L); 524 if (!timingout) { 525 timingout = 1; 526 alarm(RETRYTIME); 527 } 528 continue; 529 } 530 } 531 pid = fork(); 532 if (pid < 0) { 533 syslog(LOG_ERR, "fork: %m"); 534 if (!sep->se_wait && sep->se_socktype == SOCK_STREAM) 535 close(ctrl); 536 sigsetmask(0L); 537 sleep(1); 538 continue; 539 } 540 if (pid != 0 && sep->se_wait) { 541 sep->se_wait = pid; 542 FD_CLR(sep->se_fd, &allsock); 543 nsock--; 544 } 545 if (pid == 0 && debug) 546 setsid(); 547 } 548 sigsetmask(0L); 549 if (pid == 0) { 550 run_service(ctrl, sep); 551 if (dofork) 552 exit(0); 553 } 554 if (!sep->se_wait && sep->se_socktype == SOCK_STREAM) 555 close(ctrl); 556 } 557 } 558 } 559 } 560 561 void 562 run_service(ctrl, sep) 563 int ctrl; 564 struct servtab *sep; 565 { 566 struct passwd *pwd; 567 struct group *grp = NULL; /* XXX gcc */ 568 char buf[7]; 569 #ifdef LIBWRAP 570 struct request_info req; 571 int denied; 572 char *service = NULL; /* XXX gcc */ 573 #endif 574 575 #ifdef LIBWRAP 576 #ifndef LIBWRAP_INTERNAL 577 if (sep->se_bi == 0) 578 #endif 579 if (!sep->se_wait && sep->se_socktype == SOCK_STREAM) { 580 request_init(&req, RQ_DAEMON, sep->se_argv[0] ? 581 sep->se_argv[0] : sep->se_service, RQ_FILE, ctrl, NULL); 582 fromhost(&req); 583 denied = !hosts_access(&req); 584 if (denied || lflag) { 585 sp = getservbyport(sep->se_ctrladdr_in.sin_port, 586 sep->se_proto); 587 if (sp == NULL) { 588 (void)snprintf(buf, sizeof buf, "%d", 589 ntohs(sep->se_ctrladdr_in.sin_port)); 590 service = buf; 591 } else 592 service = sp->s_name; 593 } 594 if (denied) { 595 syslog(deny_severity, 596 "refused connection from %.500s, service %s (%s)", 597 eval_client(&req), service, sep->se_proto); 598 goto reject; 599 } 600 if (lflag) { 601 syslog(allow_severity, 602 "connection from %.500s, service %s (%s)", 603 eval_client(&req), service, sep->se_proto); 604 } 605 } 606 #endif /* LIBWRAP */ 607 608 if (sep->se_bi) { 609 (*sep->se_bi->bi_fn)(ctrl, sep); 610 } else { 611 if ((pwd = getpwnam(sep->se_user)) == NULL) { 612 syslog(LOG_ERR, "%s/%s: %s: No such user", 613 sep->se_service, sep->se_proto, sep->se_user); 614 goto reject; 615 } 616 if (sep->se_group && 617 (grp = getgrnam(sep->se_group)) == NULL) { 618 syslog(LOG_ERR, "%s/%s: %s: No such group", 619 sep->se_service, sep->se_proto, sep->se_group); 620 goto reject; 621 } 622 if (pwd->pw_uid) { 623 if (sep->se_group) 624 pwd->pw_gid = grp->gr_gid; 625 if (setgid(pwd->pw_gid) < 0) { 626 syslog(LOG_ERR, 627 "%s/%s: can't set gid %d: %m", sep->se_service, 628 sep->se_proto, pwd->pw_gid); 629 goto reject; 630 } 631 (void) initgroups(pwd->pw_name, 632 pwd->pw_gid); 633 if (setuid(pwd->pw_uid) < 0) { 634 syslog(LOG_ERR, 635 "%s/%s: can't set uid %d: %m", sep->se_service, 636 sep->se_proto, pwd->pw_uid); 637 goto reject; 638 } 639 } else if (sep->se_group) { 640 (void) setgid((gid_t)grp->gr_gid); 641 } 642 if (debug) 643 fprintf(stderr, "%d execl %s\n", 644 getpid(), sep->se_server); 645 #ifdef MULOG 646 if (sep->se_log) 647 dolog(sep, ctrl); 648 #endif 649 /* Set our control descriptor to not close-on-exec... */ 650 if (fcntl(ctrl, F_SETFD, 0) < 0) 651 syslog(LOG_ERR, "fcntl (F_SETFD, 0): %m"); 652 /* ...and dup it to stdin, stdout, and stderr. */ 653 if (ctrl != 0) { 654 dup2(ctrl, 0); 655 close(ctrl); 656 ctrl = 0; 657 } 658 dup2(0, 1); 659 dup2(0, 2); 660 #ifdef RLIMIT_NOFILE 661 if (rlim_ofile.rlim_cur != rlim_ofile_cur && 662 setrlimit(RLIMIT_NOFILE, &rlim_ofile) < 0) 663 syslog(LOG_ERR, "setrlimit: %m"); 664 #endif 665 execv(sep->se_server, sep->se_argv); 666 syslog(LOG_ERR, "cannot execute %s: %m", sep->se_server); 667 reject: 668 if (sep->se_socktype != SOCK_STREAM) 669 recv(ctrl, buf, sizeof (buf), 0); 670 _exit(1); 671 } 672 } 673 674 void 675 reapchild(signo) 676 int signo; 677 { 678 int status; 679 pid_t pid; 680 struct servtab *sep; 681 682 for (;;) { 683 pid = wait3(&status, WNOHANG, (struct rusage *)0); 684 if (pid <= 0) 685 break; 686 if (debug) 687 fprintf(stderr, "%d reaped, status %#x\n", 688 pid, status); 689 for (sep = servtab; sep; sep = sep->se_next) 690 if (sep->se_wait == pid) { 691 if (WIFEXITED(status) && WEXITSTATUS(status)) 692 syslog(LOG_WARNING, 693 "%s: exit status 0x%x", 694 sep->se_server, WEXITSTATUS(status)); 695 else if (WIFSIGNALED(status)) 696 syslog(LOG_WARNING, 697 "%s: exit signal 0x%x", 698 sep->se_server, WTERMSIG(status)); 699 sep->se_wait = 1; 700 FD_SET(sep->se_fd, &allsock); 701 nsock++; 702 if (debug) 703 fprintf(stderr, "restored %s, fd %d\n", 704 sep->se_service, sep->se_fd); 705 } 706 } 707 } 708 709 void 710 config(signo) 711 int signo; 712 { 713 struct servtab *sep, *cp, **sepp; 714 long omask; 715 int n; 716 717 if (!setconfig()) { 718 syslog(LOG_ERR, "%s: %m", CONFIG); 719 return; 720 } 721 for (sep = servtab; sep; sep = sep->se_next) 722 sep->se_checked = 0; 723 while ((cp = getconfigent())) { 724 for (sep = servtab; sep; sep = sep->se_next) 725 if (strcmp(sep->se_service, cp->se_service) == 0 && 726 strcmp(sep->se_hostaddr, cp->se_hostaddr) == 0 && 727 strcmp(sep->se_proto, cp->se_proto) == 0 && 728 ISMUX(sep) == ISMUX(cp)) 729 break; 730 if (sep != 0) { 731 int i; 732 733 #define SWAP(type, a, b) {type c=(type)a; (type)a=(type)b; (type)b=(type)c;} 734 735 omask = sigblock(SIGBLOCK); 736 /* 737 * sep->se_wait may be holding the pid of a daemon 738 * that we're waiting for. If so, don't overwrite 739 * it unless the config file explicitly says don't 740 * wait. 741 */ 742 if (cp->se_bi == 0 && 743 (sep->se_wait == 1 || cp->se_wait == 0)) 744 sep->se_wait = cp->se_wait; 745 SWAP(char *, sep->se_user, cp->se_user); 746 SWAP(char *, sep->se_group, cp->se_group); 747 SWAP(char *, sep->se_server, cp->se_server); 748 for (i = 0; i < MAXARGV; i++) 749 SWAP(char *, sep->se_argv[i], cp->se_argv[i]); 750 SWAP(int, cp->se_type, sep->se_type); 751 SWAP(int, cp->se_max, sep->se_max); 752 #undef SWAP 753 if (isrpcservice(sep)) 754 unregister_rpc(sep); 755 sep->se_rpcversl = cp->se_rpcversl; 756 sep->se_rpcversh = cp->se_rpcversh; 757 sigsetmask(omask); 758 freeconfig(cp); 759 if (debug) 760 print_service("REDO", sep); 761 } else { 762 sep = enter(cp); 763 if (debug) 764 print_service("ADD ", sep); 765 } 766 sep->se_checked = 1; 767 768 switch (sep->se_family) { 769 case AF_UNIX: 770 if (sep->se_fd != -1) 771 break; 772 n = strlen(sep->se_service); 773 if (n > sizeof(sep->se_ctrladdr_un.sun_path)) { 774 syslog(LOG_ERR, "%s: address too long", 775 sep->se_service); 776 sep->se_checked = 0; 777 continue; 778 } 779 (void)unlink(sep->se_service); 780 strncpy(sep->se_ctrladdr_un.sun_path, 781 sep->se_service, n); 782 sep->se_ctrladdr_un.sun_family = AF_UNIX; 783 sep->se_ctrladdr_size = n + 784 sizeof(sep->se_ctrladdr_un) - 785 sizeof(sep->se_ctrladdr_un.sun_path); 786 if (!ISMUX(sep)) 787 setup(sep); 788 break; 789 case AF_INET: 790 sep->se_ctrladdr_in.sin_family = AF_INET; 791 if (!strcmp(sep->se_hostaddr,"*")) 792 sep->se_ctrladdr_in.sin_addr.s_addr = 793 INADDR_ANY; 794 else if (!inet_aton(sep->se_hostaddr, 795 &sep->se_ctrladdr_in.sin_addr)) { 796 /* Do we really want to support hostname lookups here? */ 797 struct hostent *hp; 798 hp = gethostbyname(sep->se_hostaddr); 799 if (hp == 0) { 800 syslog(LOG_ERR, "%s: unknown host", 801 sep->se_hostaddr); 802 sep->se_checked = 0; 803 continue; 804 } else if (hp->h_addrtype != AF_INET) { 805 syslog(LOG_ERR, 806 "%s: address isn't an Internet address", 807 sep->se_hostaddr); 808 sep->se_checked = 0; 809 continue; 810 } else if (hp->h_length != sizeof(struct in_addr)) { 811 syslog(LOG_ERR, 812 "%s: address size wrong (under DNS corruption attack?)", 813 sep->se_hostaddr); 814 sep->se_checked = 0; 815 continue; 816 } else { 817 memcpy(&sep->se_ctrladdr_in.sin_addr, 818 hp->h_addr_list[0], 819 sizeof(struct in_addr)); 820 } 821 } 822 if (ISMUX(sep)) { 823 sep->se_fd = -1; 824 continue; 825 } 826 sep->se_ctrladdr_size = sizeof(sep->se_ctrladdr_in); 827 if (isrpcservice(sep)) { 828 struct rpcent *rp; 829 830 sep->se_rpcprog = atoi(sep->se_service); 831 if (sep->se_rpcprog == 0) { 832 rp = getrpcbyname(sep->se_service); 833 if (rp == 0) { 834 syslog(LOG_ERR, 835 "%s/%s: unknown service", 836 sep->se_service, 837 sep->se_proto); 838 sep->se_checked = 0; 839 continue; 840 } 841 sep->se_rpcprog = rp->r_number; 842 } 843 if (sep->se_fd == -1 && !ISMUX(sep)) 844 setup(sep); 845 if (sep->se_fd != -1) 846 register_rpc(sep); 847 } else { 848 u_short port = htons(atoi(sep->se_service)); 849 850 if (!port) { 851 sp = getservbyname(sep->se_service, 852 sep->se_proto); 853 if (sp == 0) { 854 syslog(LOG_ERR, 855 "%s/%s: unknown service", 856 sep->se_service, 857 sep->se_proto); 858 sep->se_checked = 0; 859 continue; 860 } 861 port = sp->s_port; 862 } 863 if (port != sep->se_ctrladdr_in.sin_port) { 864 sep->se_ctrladdr_in.sin_port = port; 865 if (sep->se_fd >= 0) 866 close_sep(sep); 867 } 868 if (sep->se_fd == -1 && !ISMUX(sep)) 869 setup(sep); 870 } 871 } 872 } 873 endconfig(); 874 /* 875 * Purge anything not looked at above. 876 */ 877 omask = sigblock(SIGBLOCK); 878 sepp = &servtab; 879 while ((sep = *sepp)) { 880 if (sep->se_checked) { 881 sepp = &sep->se_next; 882 continue; 883 } 884 *sepp = sep->se_next; 885 if (sep->se_fd >= 0) 886 close_sep(sep); 887 if (isrpcservice(sep)) 888 unregister_rpc(sep); 889 if (sep->se_family == AF_UNIX) 890 (void)unlink(sep->se_service); 891 if (debug) 892 print_service("FREE", sep); 893 freeconfig(sep); 894 free((char *)sep); 895 } 896 (void) sigsetmask(omask); 897 } 898 899 void 900 retry(signo) 901 int signo; 902 { 903 struct servtab *sep; 904 905 timingout = 0; 906 for (sep = servtab; sep; sep = sep->se_next) { 907 if (sep->se_fd == -1 && !ISMUX(sep)) { 908 switch (sep->se_family) { 909 case AF_UNIX: 910 case AF_INET: 911 setup(sep); 912 if (sep->se_fd != -1 && isrpcservice(sep)) 913 register_rpc(sep); 914 break; 915 } 916 } 917 } 918 } 919 920 void 921 goaway(signo) 922 int signo; 923 { 924 struct servtab *sep; 925 926 for (sep = servtab; sep; sep = sep->se_next) { 927 if (sep->se_fd == -1) 928 continue; 929 930 switch (sep->se_family) { 931 case AF_UNIX: 932 (void)unlink(sep->se_service); 933 break; 934 case AF_INET: 935 if (sep->se_wait == 1 && isrpcservice(sep)) 936 unregister_rpc(sep); 937 break; 938 } 939 (void)close(sep->se_fd); 940 } 941 (void)unlink(_PATH_INETDPID); 942 exit(0); 943 } 944 945 void 946 setup(sep) 947 struct servtab *sep; 948 { 949 int on = 1; 950 951 if ((sep->se_fd = socket(sep->se_family, sep->se_socktype, 0)) < 0) { 952 if (debug) 953 fprintf(stderr, "socket failed on %s/%s: %s\n", 954 sep->se_service, sep->se_proto, strerror(errno)); 955 syslog(LOG_ERR, "%s/%s: socket: %m", 956 sep->se_service, sep->se_proto); 957 return; 958 } 959 /* Set all listening sockets to close-on-exec. */ 960 if (fcntl(sep->se_fd, F_SETFD, FD_CLOEXEC) < 0) 961 syslog(LOG_ERR, "fcntl (F_SETFD, FD_CLOEXEC): %m"); 962 #define turnon(fd, opt) \ 963 setsockopt(fd, SOL_SOCKET, opt, (char *)&on, sizeof (on)) 964 if (strcmp(sep->se_proto, "tcp") == 0 && (options & SO_DEBUG) && 965 turnon(sep->se_fd, SO_DEBUG) < 0) 966 syslog(LOG_ERR, "setsockopt (SO_DEBUG): %m"); 967 if (turnon(sep->se_fd, SO_REUSEADDR) < 0) 968 syslog(LOG_ERR, "setsockopt (SO_REUSEADDR): %m"); 969 #undef turnon 970 if (bind(sep->se_fd, &sep->se_ctrladdr, sep->se_ctrladdr_size) < 0) { 971 if (debug) 972 fprintf(stderr, "bind failed on %s/%s: %s\n", 973 sep->se_service, sep->se_proto, strerror(errno)); 974 syslog(LOG_ERR, "%s/%s: bind: %m", 975 sep->se_service, sep->se_proto); 976 (void) close(sep->se_fd); 977 sep->se_fd = -1; 978 if (!timingout) { 979 timingout = 1; 980 alarm(RETRYTIME); 981 } 982 return; 983 } 984 if (sep->se_socktype == SOCK_STREAM) 985 listen(sep->se_fd, 10); 986 987 FD_SET(sep->se_fd, &allsock); 988 nsock++; 989 if (sep->se_fd > maxsock) { 990 maxsock = sep->se_fd; 991 if (maxsock > rlim_ofile_cur - FD_MARGIN) 992 bump_nofile(); 993 } 994 if (debug) 995 fprintf(stderr, "registered %s on %d\n", 996 sep->se_server, sep->se_fd); 997 } 998 999 /* 1000 * Finish with a service and its socket. 1001 */ 1002 void 1003 close_sep(sep) 1004 struct servtab *sep; 1005 { 1006 if (sep->se_fd >= 0) { 1007 nsock--; 1008 FD_CLR(sep->se_fd, &allsock); 1009 (void) close(sep->se_fd); 1010 sep->se_fd = -1; 1011 } 1012 sep->se_count = 0; 1013 /* 1014 * Don't keep the pid of this running deamon: when reapchild() 1015 * reaps this pid, it would erroneously increment nsock. 1016 */ 1017 if (sep->se_wait > 1) 1018 sep->se_wait = 1; 1019 } 1020 1021 void 1022 register_rpc(sep) 1023 struct servtab *sep; 1024 { 1025 #ifdef RPC 1026 int n; 1027 struct sockaddr_in sin; 1028 struct protoent *pp; 1029 1030 if ((pp = getprotobyname(sep->se_proto+4)) == NULL) { 1031 syslog(LOG_ERR, "%s: getproto: %m", 1032 sep->se_proto); 1033 return; 1034 } 1035 n = sizeof sin; 1036 if (getsockname(sep->se_fd, (struct sockaddr *)&sin, &n) < 0) { 1037 syslog(LOG_ERR, "%s/%s: getsockname: %m", 1038 sep->se_service, sep->se_proto); 1039 return; 1040 } 1041 1042 for (n = sep->se_rpcversl; n <= sep->se_rpcversh; n++) { 1043 if (debug) 1044 fprintf(stderr, "pmap_set: %u %u %u %u\n", 1045 sep->se_rpcprog, n, pp->p_proto, 1046 ntohs(sin.sin_port)); 1047 (void)pmap_unset(sep->se_rpcprog, n); 1048 if (!pmap_set(sep->se_rpcprog, n, pp->p_proto, ntohs(sin.sin_port))) 1049 syslog(LOG_ERR, "pmap_set: %u %u %u %u: %m", 1050 sep->se_rpcprog, n, pp->p_proto, 1051 ntohs(sin.sin_port)); 1052 } 1053 #endif /* RPC */ 1054 } 1055 1056 void 1057 unregister_rpc(sep) 1058 struct servtab *sep; 1059 { 1060 #ifdef RPC 1061 int n; 1062 1063 for (n = sep->se_rpcversl; n <= sep->se_rpcversh; n++) { 1064 if (debug) 1065 fprintf(stderr, "pmap_unset(%u, %u)\n", 1066 sep->se_rpcprog, n); 1067 if (!pmap_unset(sep->se_rpcprog, n)) 1068 syslog(LOG_ERR, "pmap_unset(%u, %u)\n", 1069 sep->se_rpcprog, n); 1070 } 1071 #endif /* RPC */ 1072 } 1073 1074 1075 struct servtab * 1076 enter(cp) 1077 struct servtab *cp; 1078 { 1079 struct servtab *sep; 1080 long omask; 1081 1082 sep = (struct servtab *)malloc(sizeof (*sep)); 1083 if (sep == (struct servtab *)0) { 1084 syslog(LOG_ERR, "Out of memory."); 1085 exit(-1); 1086 } 1087 *sep = *cp; 1088 sep->se_fd = -1; 1089 sep->se_rpcprog = -1; 1090 omask = sigblock(SIGBLOCK); 1091 sep->se_next = servtab; 1092 servtab = sep; 1093 sigsetmask(omask); 1094 return (sep); 1095 } 1096 1097 FILE *fconfig = NULL; 1098 struct servtab serv; 1099 char line[LINE_MAX]; 1100 char *defhost; 1101 1102 int 1103 setconfig() 1104 { 1105 if (defhost) free(defhost); 1106 defhost = newstr("*"); 1107 if (fconfig != NULL) { 1108 fseek(fconfig, 0L, SEEK_SET); 1109 return (1); 1110 } 1111 fconfig = fopen(CONFIG, "r"); 1112 return (fconfig != NULL); 1113 } 1114 1115 void 1116 endconfig() 1117 { 1118 if (fconfig) { 1119 (void) fclose(fconfig); 1120 fconfig = NULL; 1121 } 1122 if (defhost) { 1123 free(defhost); 1124 defhost = 0; 1125 } 1126 } 1127 1128 struct servtab * 1129 getconfigent() 1130 { 1131 struct servtab *sep = &serv; 1132 int argc; 1133 char *cp, *arg; 1134 static char TCPMUX_TOKEN[] = "tcpmux/"; 1135 #define MUX_LEN (sizeof(TCPMUX_TOKEN)-1) 1136 char *hostdelim; 1137 1138 more: 1139 #ifdef MULOG 1140 while ((cp = nextline(fconfig)) && (*cp == '#' || *cp == '\0')) { 1141 /* Avoid use of `skip' if there is a danger of it looking 1142 * at continuation lines. 1143 */ 1144 do { 1145 cp++; 1146 } while (*cp == ' ' || *cp == '\t'); 1147 if (*cp == '\0') 1148 continue; 1149 if ((arg = skip(&cp)) == NULL) 1150 continue; 1151 if (strcmp(arg, "DOMAIN")) 1152 continue; 1153 if (curdom) 1154 free(curdom); 1155 curdom = NULL; 1156 while (*cp == ' ' || *cp == '\t') 1157 cp++; 1158 if (*cp == '\0') 1159 continue; 1160 arg = cp; 1161 while (*cp && *cp != ' ' && *cp != '\t') 1162 cp++; 1163 if (*cp != '\0') 1164 *cp++ = '\0'; 1165 curdom = newstr(arg); 1166 } 1167 #else 1168 while ((cp = nextline(fconfig)) && (*cp == '#' || *cp == '\0')) 1169 ; 1170 #endif 1171 if (cp == NULL) 1172 return ((struct servtab *)0); 1173 /* 1174 * clear the static buffer, since some fields (se_ctrladdr, 1175 * for example) don't get initialized here. 1176 */ 1177 memset((caddr_t)sep, 0, sizeof *sep); 1178 arg = skip(&cp); 1179 if (cp == NULL) { 1180 /* got an empty line containing just blanks/tabs. */ 1181 goto more; 1182 } 1183 /* Check for a host name. */ 1184 hostdelim = strrchr(arg, ':'); 1185 if (hostdelim) { 1186 *hostdelim = '\0'; 1187 sep->se_hostaddr = newstr(arg); 1188 arg = hostdelim + 1; 1189 /* 1190 * If the line is of the form `host:', then just change the 1191 * default host for the following lines. 1192 */ 1193 if (*arg == '\0') { 1194 arg = skip(&cp); 1195 if (cp == NULL) { 1196 free(defhost); 1197 defhost = sep->se_hostaddr; 1198 goto more; 1199 } 1200 } 1201 } else 1202 sep->se_hostaddr = newstr(defhost); 1203 if (strncmp(arg, TCPMUX_TOKEN, MUX_LEN) == 0) { 1204 char *c = arg + MUX_LEN; 1205 if (*c == '+') { 1206 sep->se_type = MUXPLUS_TYPE; 1207 c++; 1208 } else 1209 sep->se_type = MUX_TYPE; 1210 sep->se_service = newstr(c); 1211 } else { 1212 sep->se_service = newstr(arg); 1213 sep->se_type = NORM_TYPE; 1214 } 1215 1216 arg = sskip(&cp); 1217 if (strcmp(arg, "stream") == 0) 1218 sep->se_socktype = SOCK_STREAM; 1219 else if (strcmp(arg, "dgram") == 0) 1220 sep->se_socktype = SOCK_DGRAM; 1221 else if (strcmp(arg, "rdm") == 0) 1222 sep->se_socktype = SOCK_RDM; 1223 else if (strcmp(arg, "seqpacket") == 0) 1224 sep->se_socktype = SOCK_SEQPACKET; 1225 else if (strcmp(arg, "raw") == 0) 1226 sep->se_socktype = SOCK_RAW; 1227 else 1228 sep->se_socktype = -1; 1229 1230 sep->se_proto = newstr(sskip(&cp)); 1231 if (strcmp(sep->se_proto, "unix") == 0) { 1232 sep->se_family = AF_UNIX; 1233 } else { 1234 sep->se_family = AF_INET; 1235 if (strncmp(sep->se_proto, "rpc/", 4) == 0) { 1236 #ifdef RPC 1237 char *cp, *ccp; 1238 cp = strchr(sep->se_service, '/'); 1239 if (cp == 0) { 1240 syslog(LOG_ERR, "%s: no rpc version", 1241 sep->se_service); 1242 goto more; 1243 } 1244 *cp++ = '\0'; 1245 sep->se_rpcversl = sep->se_rpcversh = 1246 strtol(cp, &ccp, 0); 1247 if (ccp == cp) { 1248 badafterall: 1249 syslog(LOG_ERR, "%s/%s: bad rpc version", 1250 sep->se_service, cp); 1251 goto more; 1252 } 1253 if (*ccp == '-') { 1254 cp = ccp + 1; 1255 sep->se_rpcversh = strtol(cp, &ccp, 0); 1256 if (ccp == cp) 1257 goto badafterall; 1258 } 1259 #else 1260 syslog(LOG_ERR, "%s: rpc services not suported", 1261 sep->se_service); 1262 goto more; 1263 #endif /* RPC */ 1264 } 1265 } 1266 arg = sskip(&cp); 1267 { 1268 char *cp; 1269 cp = strchr(arg, '.'); 1270 if (cp) { 1271 *cp++ = '\0'; 1272 sep->se_max = atoi(cp); 1273 } else 1274 sep->se_max = TOOMANY; 1275 } 1276 sep->se_wait = strcmp(arg, "wait") == 0; 1277 if (ISMUX(sep)) { 1278 /* 1279 * Silently enforce "nowait" for TCPMUX services since 1280 * they don't have an assigned port to listen on. 1281 */ 1282 sep->se_wait = 0; 1283 1284 if (strcmp(sep->se_proto, "tcp")) { 1285 syslog(LOG_ERR, 1286 "%s: bad protocol for tcpmux service %s", 1287 CONFIG, sep->se_service); 1288 goto more; 1289 } 1290 if (sep->se_socktype != SOCK_STREAM) { 1291 syslog(LOG_ERR, 1292 "%s: bad socket type for tcpmux service %s", 1293 CONFIG, sep->se_service); 1294 goto more; 1295 } 1296 } 1297 sep->se_user = newstr(sskip(&cp)); 1298 if ((sep->se_group = strchr(sep->se_user, '.'))) 1299 *sep->se_group++ = '\0'; 1300 sep->se_server = newstr(sskip(&cp)); 1301 if (strcmp(sep->se_server, "internal") == 0) { 1302 struct biltin *bi; 1303 1304 for (bi = biltins; bi->bi_service; bi++) 1305 if (bi->bi_socktype == sep->se_socktype && 1306 strcmp(bi->bi_service, sep->se_service) == 0) 1307 break; 1308 if (bi->bi_service == 0) { 1309 syslog(LOG_ERR, "internal service %s unknown", 1310 sep->se_service); 1311 goto more; 1312 } 1313 sep->se_bi = bi; 1314 sep->se_wait = bi->bi_wait; 1315 } else 1316 sep->se_bi = NULL; 1317 argc = 0; 1318 for (arg = skip(&cp); cp; arg = skip(&cp)) { 1319 #if MULOG 1320 char *colon; 1321 1322 if (argc == 0 && (colon = strrchr(arg, ':'))) { 1323 while (arg < colon) { 1324 int x; 1325 char *ccp; 1326 1327 switch (*arg++) { 1328 case 'l': 1329 x = 1; 1330 if (isdigit(*arg)) { 1331 x = strtol(arg, &ccp, 0); 1332 if (ccp == arg) 1333 break; 1334 arg = ccp; 1335 } 1336 sep->se_log &= ~MULOG_RFC931; 1337 sep->se_log |= x; 1338 break; 1339 case 'a': 1340 sep->se_log |= MULOG_RFC931; 1341 break; 1342 default: 1343 break; 1344 } 1345 } 1346 arg = colon + 1; 1347 } 1348 #endif 1349 if (argc < MAXARGV) 1350 sep->se_argv[argc++] = newstr(arg); 1351 } 1352 while (argc <= MAXARGV) 1353 sep->se_argv[argc++] = NULL; 1354 return (sep); 1355 } 1356 1357 void 1358 freeconfig(cp) 1359 struct servtab *cp; 1360 { 1361 int i; 1362 1363 if (cp->se_hostaddr) 1364 free(cp->se_hostaddr); 1365 if (cp->se_service) 1366 free(cp->se_service); 1367 if (cp->se_proto) 1368 free(cp->se_proto); 1369 if (cp->se_user) 1370 free(cp->se_user); 1371 /* Note: se_group is part of the newstr'ed se_user */ 1372 if (cp->se_server) 1373 free(cp->se_server); 1374 for (i = 0; i < MAXARGV; i++) 1375 if (cp->se_argv[i]) 1376 free(cp->se_argv[i]); 1377 } 1378 1379 1380 /* 1381 * Safe skip - if skip returns null, log a syntax error in the 1382 * configuration file and exit. 1383 */ 1384 char * 1385 sskip(cpp) 1386 char **cpp; 1387 { 1388 char *cp; 1389 1390 cp = skip(cpp); 1391 if (cp == NULL) { 1392 syslog(LOG_ERR, "%s: syntax error", CONFIG); 1393 exit(-1); 1394 } 1395 return (cp); 1396 } 1397 1398 char * 1399 skip(cpp) 1400 char **cpp; 1401 { 1402 char *cp = *cpp; 1403 char *start; 1404 1405 if (*cpp == NULL) 1406 return ((char *)0); 1407 1408 again: 1409 while (*cp == ' ' || *cp == '\t') 1410 cp++; 1411 if (*cp == '\0') { 1412 int c; 1413 1414 c = getc(fconfig); 1415 (void) ungetc(c, fconfig); 1416 if (c == ' ' || c == '\t') 1417 if ((cp = nextline(fconfig))) 1418 goto again; 1419 *cpp = (char *)0; 1420 return ((char *)0); 1421 } 1422 start = cp; 1423 while (*cp && *cp != ' ' && *cp != '\t') 1424 cp++; 1425 if (*cp != '\0') 1426 *cp++ = '\0'; 1427 *cpp = cp; 1428 return (start); 1429 } 1430 1431 char * 1432 nextline(fd) 1433 FILE *fd; 1434 { 1435 char *cp; 1436 1437 if (fgets(line, sizeof (line), fd) == NULL) 1438 return ((char *)0); 1439 cp = strchr(line, '\n'); 1440 if (cp) 1441 *cp = '\0'; 1442 return (line); 1443 } 1444 1445 char * 1446 newstr(cp) 1447 char *cp; 1448 { 1449 if ((cp = strdup(cp ? cp : ""))) 1450 return (cp); 1451 syslog(LOG_ERR, "strdup: %m"); 1452 exit(-1); 1453 } 1454 1455 void 1456 inetd_setproctitle(a, s) 1457 char *a; 1458 int s; 1459 { 1460 int size; 1461 char *cp; 1462 struct sockaddr_in sin; 1463 char buf[80]; 1464 1465 cp = Argv[0]; 1466 size = sizeof(sin); 1467 if (getpeername(s, (struct sockaddr *)&sin, &size) == 0) 1468 (void)snprintf(buf, sizeof buf, "-%s [%s]", a, 1469 inet_ntoa(sin.sin_addr)); 1470 else 1471 (void)snprintf(buf, sizeof buf, "-%s", a); 1472 strncpy(cp, buf, LastArg - cp); 1473 cp += strlen(cp); 1474 while (cp < LastArg) 1475 *cp++ = ' '; 1476 } 1477 1478 void 1479 logpid() 1480 { 1481 FILE *fp; 1482 1483 if ((fp = fopen(_PATH_INETDPID, "w")) != NULL) { 1484 fprintf(fp, "%u\n", getpid()); 1485 (void)fclose(fp); 1486 } 1487 } 1488 1489 void 1490 bump_nofile() 1491 { 1492 #ifdef RLIMIT_NOFILE 1493 1494 #define FD_CHUNK 32 1495 1496 struct rlimit rl; 1497 1498 if (getrlimit(RLIMIT_NOFILE, &rl) < 0) { 1499 syslog(LOG_ERR, "getrlimit: %m"); 1500 return; 1501 } 1502 rl.rlim_cur = MIN(rl.rlim_max, rl.rlim_cur + FD_CHUNK); 1503 if (rl.rlim_cur <= rlim_ofile_cur) { 1504 syslog(LOG_ERR, 1505 "bump_nofile: cannot extend file limit, max = %d", 1506 (int)rl.rlim_cur); 1507 return; 1508 } 1509 1510 if (setrlimit(RLIMIT_NOFILE, &rl) < 0) { 1511 syslog(LOG_ERR, "setrlimit: %m"); 1512 return; 1513 } 1514 1515 rlim_ofile_cur = rl.rlim_cur; 1516 return; 1517 1518 #else 1519 syslog(LOG_ERR, "bump_nofile: cannot extend file limit"); 1520 return; 1521 #endif 1522 } 1523 1524 /* 1525 * Internet services provided internally by inetd: 1526 */ 1527 #define BUFSIZE 4096 1528 1529 /* ARGSUSED */ 1530 void 1531 echo_stream(s, sep) /* Echo service -- echo data back */ 1532 int s; 1533 struct servtab *sep; 1534 { 1535 char buffer[BUFSIZE]; 1536 int i; 1537 1538 inetd_setproctitle(sep->se_service, s); 1539 while ((i = read(s, buffer, sizeof(buffer))) > 0 && 1540 write(s, buffer, i) > 0) 1541 ; 1542 } 1543 1544 /* ARGSUSED */ 1545 void 1546 echo_dg(s, sep) /* Echo service -- echo data back */ 1547 int s; 1548 struct servtab *sep; 1549 { 1550 char buffer[BUFSIZE]; 1551 int i, size; 1552 struct sockaddr sa; 1553 1554 size = sizeof(sa); 1555 if ((i = recvfrom(s, buffer, sizeof(buffer), 0, &sa, &size)) < 0) 1556 return; 1557 (void) sendto(s, buffer, i, 0, &sa, sizeof(sa)); 1558 } 1559 1560 /* ARGSUSED */ 1561 void 1562 discard_stream(s, sep) /* Discard service -- ignore data */ 1563 int s; 1564 struct servtab *sep; 1565 { 1566 char buffer[BUFSIZE]; 1567 1568 inetd_setproctitle(sep->se_service, s); 1569 while ((errno = 0, read(s, buffer, sizeof(buffer)) > 0) || 1570 errno == EINTR) 1571 ; 1572 } 1573 1574 /* ARGSUSED */ 1575 void 1576 discard_dg(s, sep) /* Discard service -- ignore data */ 1577 int s; 1578 struct servtab *sep; 1579 { 1580 char buffer[BUFSIZE]; 1581 1582 (void) read(s, buffer, sizeof(buffer)); 1583 } 1584 1585 #include <ctype.h> 1586 #define LINESIZ 72 1587 char ring[128]; 1588 char *endring; 1589 1590 void 1591 initring() 1592 { 1593 int i; 1594 1595 endring = ring; 1596 1597 for (i = 0; i <= 128; ++i) 1598 if (isprint(i)) 1599 *endring++ = i; 1600 } 1601 1602 /* ARGSUSED */ 1603 void 1604 chargen_stream(s, sep) /* Character generator */ 1605 int s; 1606 struct servtab *sep; 1607 { 1608 int len; 1609 char *rs, text[LINESIZ+2]; 1610 1611 inetd_setproctitle(sep->se_service, s); 1612 1613 if (!endring) { 1614 initring(); 1615 rs = ring; 1616 } 1617 1618 text[LINESIZ] = '\r'; 1619 text[LINESIZ + 1] = '\n'; 1620 for (rs = ring;;) { 1621 if ((len = endring - rs) >= LINESIZ) 1622 memmove(text, rs, LINESIZ); 1623 else { 1624 memmove(text, rs, len); 1625 memmove(text + len, ring, LINESIZ - len); 1626 } 1627 if (++rs == endring) 1628 rs = ring; 1629 if (write(s, text, sizeof(text)) != sizeof(text)) 1630 break; 1631 } 1632 } 1633 1634 /* ARGSUSED */ 1635 void 1636 chargen_dg(s, sep) /* Character generator */ 1637 int s; 1638 struct servtab *sep; 1639 { 1640 struct sockaddr sa; 1641 static char *rs; 1642 int len, size; 1643 char text[LINESIZ+2]; 1644 1645 if (endring == 0) { 1646 initring(); 1647 rs = ring; 1648 } 1649 1650 size = sizeof(sa); 1651 if (recvfrom(s, text, sizeof(text), 0, &sa, &size) < 0) 1652 return; 1653 1654 if ((len = endring - rs) >= LINESIZ) 1655 memmove(text, rs, LINESIZ); 1656 else { 1657 memmove(text, rs, len); 1658 memmove(text + len, ring, LINESIZ - len); 1659 } 1660 if (++rs == endring) 1661 rs = ring; 1662 text[LINESIZ] = '\r'; 1663 text[LINESIZ + 1] = '\n'; 1664 (void) sendto(s, text, sizeof(text), 0, &sa, sizeof(sa)); 1665 } 1666 1667 /* 1668 * Return a machine readable date and time, in the form of the 1669 * number of seconds since midnight, Jan 1, 1900. Since gettimeofday 1670 * returns the number of seconds since midnight, Jan 1, 1970, 1671 * we must add 2208988800 seconds to this figure to make up for 1672 * some seventy years Bell Labs was asleep. 1673 */ 1674 1675 long 1676 machtime() 1677 { 1678 struct timeval tv; 1679 1680 if (gettimeofday(&tv, (struct timezone *)0) < 0) { 1681 if (debug) 1682 fprintf(stderr, "Unable to get time of day\n"); 1683 return (0L); 1684 } 1685 #define OFFSET ((u_long)25567 * 24*60*60) 1686 return (htonl((long)(tv.tv_sec + OFFSET))); 1687 #undef OFFSET 1688 } 1689 1690 /* ARGSUSED */ 1691 void 1692 machtime_stream(s, sep) 1693 int s; 1694 struct servtab *sep; 1695 { 1696 long result; 1697 1698 result = machtime(); 1699 (void) write(s, (char *) &result, sizeof(result)); 1700 } 1701 1702 /* ARGSUSED */ 1703 void 1704 machtime_dg(s, sep) 1705 int s; 1706 struct servtab *sep; 1707 { 1708 long result; 1709 struct sockaddr sa; 1710 int size; 1711 1712 size = sizeof(sa); 1713 if (recvfrom(s, (char *)&result, sizeof(result), 0, &sa, &size) < 0) 1714 return; 1715 result = machtime(); 1716 (void) sendto(s, (char *) &result, sizeof(result), 0, &sa, sizeof(sa)); 1717 } 1718 1719 /* ARGSUSED */ 1720 void 1721 daytime_stream(s, sep) /* Return human-readable time of day */ 1722 int s; 1723 struct servtab *sep; 1724 { 1725 char buffer[256]; 1726 time_t clock; 1727 int len; 1728 1729 clock = time((time_t *) 0); 1730 1731 len = snprintf(buffer, sizeof buffer, "%.24s\r\n", ctime(&clock)); 1732 (void) write(s, buffer, len); 1733 } 1734 1735 /* ARGSUSED */ 1736 void 1737 daytime_dg(s, sep) /* Return human-readable time of day */ 1738 int s; 1739 struct servtab *sep; 1740 { 1741 char buffer[256]; 1742 time_t clock; 1743 struct sockaddr sa; 1744 int size, len; 1745 1746 clock = time((time_t *) 0); 1747 1748 size = sizeof(sa); 1749 if (recvfrom(s, buffer, sizeof(buffer), 0, &sa, &size) < 0) 1750 return; 1751 len = snprintf(buffer, sizeof buffer, "%.24s\r\n", ctime(&clock)); 1752 (void) sendto(s, buffer, len, 0, &sa, sizeof(sa)); 1753 } 1754 1755 /* 1756 * print_service: 1757 * Dump relevant information to stderr 1758 */ 1759 void 1760 print_service(action, sep) 1761 char *action; 1762 struct servtab *sep; 1763 { 1764 if (isrpcservice(sep)) 1765 fprintf(stderr, 1766 "%s: %s rpcprog=%d, rpcvers = %d/%d, proto=%s, wait.max=%d.%d, user.group=%s.%s builtin=%lx server=%s\n", 1767 action, sep->se_service, 1768 sep->se_rpcprog, sep->se_rpcversh, sep->se_rpcversl, sep->se_proto, 1769 sep->se_wait, sep->se_max, sep->se_user, sep->se_group, 1770 (long)sep->se_bi, sep->se_server); 1771 else 1772 fprintf(stderr, 1773 "%s: %s proto=%s, wait.max=%d.%d, user.group=%s.%s builtin=%lx server=%s\n", 1774 action, sep->se_service, 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 } 1778 1779 void 1780 usage() 1781 { 1782 1783 #ifdef LIBWRAP 1784 (void)fprintf(stderr, "usage: %s [-dl] [conf]\n", __progname); 1785 #else 1786 (void)fprintf(stderr, "usage: %s [-d] [conf]\n", __progname); 1787 #endif 1788 exit(1); 1789 } 1790 1791 1792 /* 1793 * Based on TCPMUX.C by Mark K. Lottor November 1988 1794 * sri-nic::ps:<mkl>tcpmux.c 1795 */ 1796 1797 static int /* # of characters upto \r,\n or \0 */ 1798 getline(fd, buf, len) 1799 int fd; 1800 char *buf; 1801 int len; 1802 { 1803 int count = 0, n; 1804 1805 do { 1806 n = read(fd, buf, len-count); 1807 if (n == 0) 1808 return (count); 1809 if (n < 0) 1810 return (-1); 1811 while (--n >= 0) { 1812 if (*buf == '\r' || *buf == '\n' || *buf == '\0') 1813 return (count); 1814 count++; 1815 buf++; 1816 } 1817 } while (count < len); 1818 return (count); 1819 } 1820 1821 #define MAX_SERV_LEN (256+2) /* 2 bytes for \r\n */ 1822 1823 #define strwrite(fd, buf) (void) write(fd, buf, sizeof(buf)-1) 1824 1825 void 1826 tcpmux(ctrl, sep) 1827 int ctrl; 1828 struct servtab *sep; 1829 { 1830 char service[MAX_SERV_LEN+1]; 1831 int len; 1832 1833 /* Get requested service name */ 1834 if ((len = getline(ctrl, service, MAX_SERV_LEN)) < 0) { 1835 strwrite(ctrl, "-Error reading service name\r\n"); 1836 goto reject; 1837 } 1838 service[len] = '\0'; 1839 1840 if (debug) 1841 fprintf(stderr, "tcpmux: someone wants %s\n", service); 1842 1843 /* 1844 * Help is a required command, and lists available services, 1845 * one per line. 1846 */ 1847 if (!strcasecmp(service, "help")) { 1848 strwrite(ctrl, "+Available services:\r\n"); 1849 strwrite(ctrl, "help\r\n"); 1850 for (sep = servtab; sep; sep = sep->se_next) { 1851 if (!ISMUX(sep)) 1852 continue; 1853 (void)write(ctrl, sep->se_service, 1854 strlen(sep->se_service)); 1855 strwrite(ctrl, "\r\n"); 1856 } 1857 goto reject; 1858 } 1859 1860 /* Try matching a service in inetd.conf with the request */ 1861 for (sep = servtab; sep; sep = sep->se_next) { 1862 if (!ISMUX(sep)) 1863 continue; 1864 if (!strcasecmp(service, sep->se_service)) { 1865 if (ISMUXPLUS(sep)) 1866 strwrite(ctrl, "+Go\r\n"); 1867 run_service(ctrl, sep); 1868 return; 1869 } 1870 } 1871 strwrite(ctrl, "-Service not available\r\n"); 1872 reject: 1873 _exit(1); 1874 } 1875 1876 1877 #ifdef MULOG 1878 dolog(sep, ctrl) 1879 struct servtab *sep; 1880 int ctrl; 1881 { 1882 struct sockaddr sa; 1883 struct sockaddr_in *sin = (struct sockaddr_in *)&sa; 1884 int len = sizeof(sa); 1885 struct hostent *hp; 1886 char *host, *dp, buf[BUFSIZ], *rfc931_name(); 1887 int connected = 1; 1888 1889 if (sep->se_family != AF_INET) 1890 return; 1891 1892 if (getpeername(ctrl, &sa, &len) < 0) { 1893 if (errno != ENOTCONN) { 1894 syslog(LOG_ERR, "getpeername: %m"); 1895 return; 1896 } 1897 if (recvfrom(ctrl, buf, sizeof(buf), MSG_PEEK, &sa, &len) < 0) { 1898 syslog(LOG_ERR, "recvfrom: %m"); 1899 return; 1900 } 1901 connected = 0; 1902 } 1903 if (sa.sa_family != AF_INET) { 1904 syslog(LOG_ERR, "unexpected address family %u", sa.sa_family); 1905 return; 1906 } 1907 1908 hp = gethostbyaddr((char *) &sin->sin_addr.s_addr, 1909 sizeof (sin->sin_addr.s_addr), AF_INET); 1910 1911 host = hp?hp->h_name:inet_ntoa(sin->sin_addr); 1912 1913 switch (sep->se_log & ~MULOG_RFC931) { 1914 case 0: 1915 return; 1916 case 1: 1917 if (curdom == NULL || *curdom == '\0') 1918 break; 1919 dp = host + strlen(host) - strlen(curdom); 1920 if (dp < host) 1921 break; 1922 if (debug) 1923 fprintf(stderr, "check \"%s\" against curdom \"%s\"\n", 1924 host, curdom); 1925 if (strcasecmp(dp, curdom) == 0) 1926 return; 1927 break; 1928 case 2: 1929 default: 1930 break; 1931 } 1932 1933 openlog("", LOG_NOWAIT, MULOG); 1934 1935 if (connected && (sep->se_log & MULOG_RFC931)) 1936 syslog(LOG_INFO, "%s@%s wants %s", 1937 rfc931_name(sin, ctrl), host, sep->se_service); 1938 else 1939 syslog(LOG_INFO, "%s wants %s", 1940 host, sep->se_service); 1941 } 1942 1943 /* 1944 * From tcp_log by 1945 * Wietse Venema, Eindhoven University of Technology, The Netherlands. 1946 */ 1947 #if 0 1948 static char sccsid[] = "@(#) rfc931.c 1.3 92/08/31 22:54:46"; 1949 #endif 1950 1951 #include <setjmp.h> 1952 1953 #define RFC931_PORT 113 /* Semi-well-known port */ 1954 #define TIMEOUT 4 1955 #define TIMEOUT2 10 1956 1957 static jmp_buf timebuf; 1958 1959 /* timeout - handle timeouts */ 1960 1961 static void timeout(sig) 1962 int sig; 1963 { 1964 longjmp(timebuf, sig); 1965 } 1966 1967 /* rfc931_name - return remote user name */ 1968 1969 char * 1970 rfc931_name(there, ctrl) 1971 struct sockaddr_in *there; /* remote link information */ 1972 int ctrl; 1973 { 1974 struct sockaddr_in here; /* local link information */ 1975 struct sockaddr_in sin; /* for talking to RFC931 daemon */ 1976 int length; 1977 int s; 1978 unsigned remote; 1979 unsigned local; 1980 static char user[256]; /* XXX */ 1981 char buf[256]; 1982 char *cp; 1983 char *result = "USER_UNKNOWN"; 1984 int len; 1985 1986 /* Find out local port number of our stdin. */ 1987 1988 length = sizeof(here); 1989 if (getsockname(ctrl, (struct sockaddr *) &here, &length) == -1) { 1990 syslog(LOG_ERR, "getsockname: %m"); 1991 return (result); 1992 } 1993 /* Set up timer so we won't get stuck. */ 1994 1995 if ((s = socket(AF_INET, SOCK_STREAM, 0)) == -1) { 1996 syslog(LOG_ERR, "socket: %m"); 1997 return (result); 1998 } 1999 2000 sin = here; 2001 sin.sin_port = htons(0); 2002 if (bind(s, (struct sockaddr *) &sin, sizeof(sin)) == -1) { 2003 syslog(LOG_ERR, "bind: %m"); 2004 return (result); 2005 } 2006 2007 signal(SIGALRM, timeout); 2008 if (setjmp(timebuf)) { 2009 close(s); /* not: fclose(fp) */ 2010 return (result); 2011 } 2012 alarm(TIMEOUT); 2013 2014 /* Connect to the RFC931 daemon. */ 2015 2016 sin = *there; 2017 sin.sin_port = htons(RFC931_PORT); 2018 if (connect(s, (struct sockaddr *) &sin, sizeof(sin)) == -1) { 2019 close(s); 2020 alarm(0); 2021 return (result); 2022 } 2023 2024 /* Query the RFC 931 server. Would 13-byte writes ever be broken up? */ 2025 (void)snprintf(buf, sizeof buf, "%u,%u\r\n", ntohs(there->sin_port), 2026 ntohs(here.sin_port)); 2027 2028 2029 for (len = 0, cp = buf; len < strlen(buf); ) { 2030 int n; 2031 2032 if ((n = write(s, cp, strlen(buf) - len)) == -1) { 2033 close(s); 2034 alarm(0); 2035 return (result); 2036 } 2037 cp += n; 2038 len += n; 2039 } 2040 2041 /* Read response */ 2042 for (cp = buf; cp < buf + sizeof(buf) - 1; ) { 2043 char c; 2044 if (read(s, &c, 1) != 1) { 2045 close(s); 2046 alarm(0); 2047 return (result); 2048 } 2049 if (c == '\n') 2050 break; 2051 *cp++ = c; 2052 } 2053 *cp = '\0'; 2054 2055 if (sscanf(buf, "%u , %u : USERID :%*[^:]:%255s", &remote, &local, user) == 3 2056 && ntohs(there->sin_port) == remote 2057 && ntohs(here.sin_port) == local) { 2058 2059 /* Strip trailing carriage return. */ 2060 if (cp = strchr(user, '\r')) 2061 *cp = 0; 2062 result = user; 2063 } 2064 2065 alarm(0); 2066 close(s); 2067 return (result); 2068 } 2069 #endif 2070
Indexes created Thu Sep 25 16:09:42 GMT 2025