1 /* $NetBSD: inetd.c,v 1.120 2012/01/04 16:09:43 drochner Exp $ */ 2 3 /*- 4 * Copyright (c) 1998, 2003 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility, 9 * NASA Ames Research Center and by Matthias Scheler. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 22 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 23 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 24 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 25 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 26 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 27 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 28 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 29 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 30 * POSSIBILITY OF SUCH DAMAGE. 31 */ 32 33 /* 34 * Copyright (c) 1983, 1991, 1993, 1994 35 * The Regents of the University of California. All rights reserved. 36 * 37 * Redistribution and use in source and binary forms, with or without 38 * modification, are permitted provided that the following conditions 39 * are met: 40 * 1. Redistributions of source code must retain the above copyright 41 * notice, this list of conditions and the following disclaimer. 42 * 2. Redistributions in binary form must reproduce the above copyright 43 * notice, this list of conditions and the following disclaimer in the 44 * documentation and/or other materials provided with the distribution. 45 * 3. Neither the name of the University nor the names of its contributors 46 * may be used to endorse or promote products derived from this software 47 * without specific prior written permission. 48 * 49 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 50 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 51 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 52 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 53 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 54 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 55 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 56 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 57 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 58 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 59 * SUCH DAMAGE. 60 */ 61 62 #include <sys/cdefs.h> 63 #ifndef lint 64 __COPYRIGHT("@(#) Copyright (c) 1983, 1991, 1993, 1994\ 65 The Regents of the University of California. All rights reserved."); 66 #if 0 67 static char sccsid[] = "@(#)inetd.c 8.4 (Berkeley) 4/13/94"; 68 #else 69 __RCSID("$NetBSD: inetd.c,v 1.120 2012/01/04 16:09:43 drochner Exp $"); 70 #endif 71 #endif /* not lint */ 72 73 /* 74 * Inetd - Internet super-server 75 * 76 * This program invokes all internet services as needed. Connection-oriented 77 * services are invoked each time a connection is made, by creating a process. 78 * This process is passed the connection as file descriptor 0 and is expected 79 * to do a getpeername to find out the source host and port. 80 * 81 * Datagram oriented services are invoked when a datagram 82 * arrives; a process is created and passed a pending message 83 * on file descriptor 0. Datagram servers may either connect 84 * to their peer, freeing up the original socket for inetd 85 * to receive further messages on, or ``take over the socket'', 86 * processing all arriving datagrams and, eventually, timing 87 * out. The first type of server is said to be ``multi-threaded''; 88 * the second type of server ``single-threaded''. 89 * 90 * Inetd uses a configuration file which is read at startup 91 * and, possibly, at some later time in response to a hangup signal. 92 * The configuration file is ``free format'' with fields given in the 93 * order shown below. Continuation lines for an entry must being with 94 * a space or tab. All fields must be present in each entry. 95 * 96 * service name must be in /etc/services or must 97 * name a tcpmux service 98 * socket type[:accf[,arg]] stream/dgram/raw/rdm/seqpacket, 99 only stream can name an accept filter 100 * protocol must be in /etc/protocols 101 * wait/nowait[:max] single-threaded/multi-threaded, max # 102 * user[:group] user/group to run daemon as 103 * server program full path name 104 * server program arguments maximum of MAXARGS (20) 105 * 106 * For RPC services 107 * service name/version must be in /etc/rpc 108 * socket type stream/dgram/raw/rdm/seqpacket 109 * protocol must be in /etc/protocols 110 * wait/nowait[:max] single-threaded/multi-threaded 111 * user[:group] user to run daemon as 112 * server program full path name 113 * server program arguments maximum of MAXARGS (20) 114 * 115 * For non-RPC services, the "service name" can be of the form 116 * hostaddress:servicename, in which case the hostaddress is used 117 * as the host portion of the address to listen on. If hostaddress 118 * consists of a single `*' character, INADDR_ANY is used. 119 * 120 * A line can also consist of just 121 * hostaddress: 122 * where hostaddress is as in the preceding paragraph. Such a line must 123 * have no further fields; the specified hostaddress is remembered and 124 * used for all further lines that have no hostaddress specified, 125 * until the next such line (or EOF). (This is why * is provided to 126 * allow explicit specification of INADDR_ANY.) A line 127 * *: 128 * is implicitly in effect at the beginning of the file. 129 * 130 * The hostaddress specifier may (and often will) contain dots; 131 * the service name must not. 132 * 133 * For RPC services, host-address specifiers are accepted and will 134 * work to some extent; however, because of limitations in the 135 * portmapper interface, it will not work to try to give more than 136 * one line for any given RPC service, even if the host-address 137 * specifiers are different. 138 * 139 * TCP services without official port numbers are handled with the 140 * RFC1078-based tcpmux internal service. Tcpmux listens on port 1 for 141 * requests. When a connection is made from a foreign host, the service 142 * requested is passed to tcpmux, which looks it up in the servtab list 143 * and returns the proper entry for the service. Tcpmux returns a 144 * negative reply if the service doesn't exist, otherwise the invoked 145 * server is expected to return the positive reply if the service type in 146 * inetd.conf file has the prefix "tcpmux/". If the service type has the 147 * prefix "tcpmux/+", tcpmux will return the positive reply for the 148 * process; this is for compatibility with older server code, and also 149 * allows you to invoke programs that use stdin/stdout without putting any 150 * special server code in them. Services that use tcpmux are "nowait" 151 * because they do not have a well-known port and hence cannot listen 152 * for new requests. 153 * 154 * Comment lines are indicated by a `#' in column 1. 155 * 156 * #ifdef IPSEC 157 * Comment lines that start with "#@" denote IPsec policy string, as described 158 * in ipsec_set_policy(3). This will affect all the following items in 159 * inetd.conf(8). To reset the policy, just use "#@" line. By default, 160 * there's no IPsec policy. 161 * #endif 162 */ 163 164 /* 165 * Here's the scoop concerning the user:group feature: 166 * 167 * 1) set-group-option off. 168 * 169 * a) user = root: NO setuid() or setgid() is done 170 * 171 * b) other: setuid() 172 * setgid(primary group as found in passwd) 173 * initgroups(name, primary group) 174 * 175 * 2) set-group-option on. 176 * 177 * a) user = root: NO setuid() 178 * setgid(specified group) 179 * NO initgroups() 180 * 181 * b) other: setuid() 182 * setgid(specified group) 183 * initgroups(name, specified group) 184 * 185 */ 186 187 #include <sys/param.h> 188 #include <sys/stat.h> 189 #include <sys/ioctl.h> 190 #include <sys/socket.h> 191 #include <sys/un.h> 192 #include <sys/wait.h> 193 #include <sys/time.h> 194 #include <sys/resource.h> 195 #include <sys/event.h> 196 197 #ifndef NO_RPC 198 #define RPC 199 #endif 200 201 #include <net/if.h> 202 203 #include <netinet/in.h> 204 #include <arpa/inet.h> 205 #ifdef RPC 206 #include <rpc/rpc.h> 207 #include <rpc/rpcb_clnt.h> 208 #include <netconfig.h> 209 #endif 210 211 #include <ctype.h> 212 #include <errno.h> 213 #include <fcntl.h> 214 #include <grp.h> 215 #include <netdb.h> 216 #include <pwd.h> 217 #include <signal.h> 218 #include <stdio.h> 219 #include <stdlib.h> 220 #include <string.h> 221 #include <syslog.h> 222 #include <unistd.h> 223 #include <util.h> 224 #include <ifaddrs.h> 225 226 #include "pathnames.h" 227 228 #ifdef IPSEC 229 #include <netipsec/ipsec.h> 230 #ifndef IPSEC_POLICY_IPSEC /* no ipsec support on old ipsec */ 231 #undef IPSEC 232 #endif 233 #include "ipsec.h" 234 #endif 235 236 #ifdef LIBWRAP 237 # include <tcpd.h> 238 #ifndef LIBWRAP_ALLOW_FACILITY 239 # define LIBWRAP_ALLOW_FACILITY LOG_AUTH 240 #endif 241 #ifndef LIBWRAP_ALLOW_SEVERITY 242 # define LIBWRAP_ALLOW_SEVERITY LOG_INFO 243 #endif 244 #ifndef LIBWRAP_DENY_FACILITY 245 # define LIBWRAP_DENY_FACILITY LOG_AUTH 246 #endif 247 #ifndef LIBWRAP_DENY_SEVERITY 248 # define LIBWRAP_DENY_SEVERITY LOG_WARNING 249 #endif 250 int allow_severity = LIBWRAP_ALLOW_FACILITY|LIBWRAP_ALLOW_SEVERITY; 251 int deny_severity = LIBWRAP_DENY_FACILITY|LIBWRAP_DENY_SEVERITY; 252 #endif 253 254 #define TOOMANY 40 /* don't start more than TOOMANY */ 255 #define CNT_INTVL 60 /* servers in CNT_INTVL sec. */ 256 #define RETRYTIME (60*10) /* retry after bind or server fail */ 257 258 #define A_CNT(a) (sizeof (a) / sizeof (a[0])) 259 260 int debug; 261 #ifdef LIBWRAP 262 int lflag; 263 #endif 264 int maxsock; 265 int kq; 266 int options; 267 int timingout; 268 const int niflags = NI_NUMERICHOST | NI_NUMERICSERV; 269 270 #ifndef OPEN_MAX 271 #define OPEN_MAX 64 272 #endif 273 274 /* Reserve some descriptors, 3 stdio + at least: 1 log, 1 conf. file */ 275 #define FD_MARGIN (8) 276 rlim_t rlim_ofile_cur = OPEN_MAX; 277 278 struct rlimit rlim_ofile; 279 280 struct kevent changebuf[64]; 281 size_t changes; 282 283 struct servtab { 284 char *se_hostaddr; /* host address to listen on */ 285 char *se_service; /* name of service */ 286 int se_socktype; /* type of socket to use */ 287 int se_family; /* address family */ 288 char *se_proto; /* protocol used */ 289 int se_sndbuf; /* sndbuf size */ 290 int se_rcvbuf; /* rcvbuf size */ 291 int se_rpcprog; /* rpc program number */ 292 int se_rpcversl; /* rpc program lowest version */ 293 int se_rpcversh; /* rpc program highest version */ 294 #define isrpcservice(sep) ((sep)->se_rpcversl != 0) 295 pid_t se_wait; /* single threaded server */ 296 short se_checked; /* looked at during merge */ 297 char *se_user; /* user name to run as */ 298 char *se_group; /* group name to run as */ 299 struct biltin *se_bi; /* if built-in, description */ 300 char *se_server; /* server program */ 301 #define MAXARGV 20 302 char *se_argv[MAXARGV+1]; /* program arguments */ 303 #ifdef IPSEC 304 char *se_policy; /* IPsec poilcy string */ 305 #endif 306 struct accept_filter_arg se_accf; /* accept filter for stream service */ 307 int se_fd; /* open descriptor */ 308 int se_type; /* type */ 309 union { 310 struct sockaddr se_un_ctrladdr; 311 struct sockaddr_in se_un_ctrladdr_in; 312 struct sockaddr_in6 se_un_ctrladdr_in6; 313 struct sockaddr_un se_un_ctrladdr_un; 314 } se_un; /* bound address */ 315 #define se_ctrladdr se_un.se_un_ctrladdr 316 #define se_ctrladdr_in se_un.se_un_ctrladdr_in 317 #define se_ctrladdr_un se_un.se_un_ctrladdr_un 318 int se_ctrladdr_size; 319 int se_max; /* max # of instances of this service */ 320 int se_count; /* number started since se_time */ 321 struct timeval se_time; /* start of se_count */ 322 struct servtab *se_next; 323 } *servtab; 324 325 #define NORM_TYPE 0 326 #define MUX_TYPE 1 327 #define MUXPLUS_TYPE 2 328 #define FAITH_TYPE 3 329 #define ISMUX(sep) (((sep)->se_type == MUX_TYPE) || \ 330 ((sep)->se_type == MUXPLUS_TYPE)) 331 #define ISMUXPLUS(sep) ((sep)->se_type == MUXPLUS_TYPE) 332 333 334 static void chargen_dg(int, struct servtab *); 335 static void chargen_stream(int, struct servtab *); 336 static void close_sep(struct servtab *); 337 static void config(void); 338 static void daytime_dg(int, struct servtab *); 339 static void daytime_stream(int, struct servtab *); 340 static void discard_dg(int, struct servtab *); 341 static void discard_stream(int, struct servtab *); 342 static void echo_dg(int, struct servtab *); 343 static void echo_stream(int, struct servtab *); 344 static void endconfig(void); 345 static struct servtab *enter(struct servtab *); 346 static void freeconfig(struct servtab *); 347 static struct servtab *getconfigent(void); 348 __dead static void goaway(void); 349 static void machtime_dg(int, struct servtab *); 350 static void machtime_stream(int, struct servtab *); 351 static char *newstr(const char *); 352 static char *nextline(FILE *); 353 static void print_service(const char *, struct servtab *); 354 static void reapchild(void); 355 static void retry(void); 356 static void run_service(int, struct servtab *, int); 357 static int setconfig(void); 358 static void setup(struct servtab *); 359 static char *sskip(char **); 360 static char *skip(char **); 361 static void tcpmux(int, struct servtab *); 362 __dead static void usage(void); 363 static void register_rpc(struct servtab *); 364 static void unregister_rpc(struct servtab *); 365 static void bump_nofile(void); 366 static void inetd_setproctitle(char *, int); 367 static void initring(void); 368 static uint32_t machtime(void); 369 static int port_good_dg(struct sockaddr *); 370 static int dg_broadcast(struct in_addr *); 371 static int my_kevent(const struct kevent *, size_t, struct kevent *, 372 size_t); 373 static struct kevent * allocchange(void); 374 static int get_line(int, char *, int); 375 static void spawn(struct servtab *, int); 376 377 struct biltin { 378 const char *bi_service; /* internally provided service name */ 379 int bi_socktype; /* type of socket supported */ 380 short bi_fork; /* 1 if should fork before call */ 381 short bi_wait; /* 1 if should wait for child */ 382 void (*bi_fn)(int, struct servtab *); 383 /* function which performs it */ 384 } biltins[] = { 385 /* Echo received data */ 386 { "echo", SOCK_STREAM, 1, 0, echo_stream }, 387 { "echo", SOCK_DGRAM, 0, 0, echo_dg }, 388 389 /* Internet /dev/null */ 390 { "discard", SOCK_STREAM, 1, 0, discard_stream }, 391 { "discard", SOCK_DGRAM, 0, 0, discard_dg }, 392 393 /* Return 32 bit time since 1970 */ 394 { "time", SOCK_STREAM, 0, 0, machtime_stream }, 395 { "time", SOCK_DGRAM, 0, 0, machtime_dg }, 396 397 /* Return human-readable time */ 398 { "daytime", SOCK_STREAM, 0, 0, daytime_stream }, 399 { "daytime", SOCK_DGRAM, 0, 0, daytime_dg }, 400 401 /* Familiar character generator */ 402 { "chargen", SOCK_STREAM, 1, 0, chargen_stream }, 403 { "chargen", SOCK_DGRAM, 0, 0, chargen_dg }, 404 405 { "tcpmux", SOCK_STREAM, 1, 0, tcpmux }, 406 407 { NULL, 0, 0, 0, NULL } 408 }; 409 410 /* list of "bad" ports. I.e. ports that are most obviously used for 411 * "cycling packets" denial of service attacks. See /etc/services. 412 * List must end with port number "0". 413 */ 414 415 u_int16_t bad_ports[] = { 7, 9, 13, 19, 37, 0 }; 416 417 418 #define NUMINT (sizeof(intab) / sizeof(struct inent)) 419 const char *CONFIG = _PATH_INETDCONF; 420 421 static int my_signals[] = 422 { SIGALRM, SIGHUP, SIGCHLD, SIGTERM, SIGINT, SIGPIPE }; 423 424 int 425 main(int argc, char *argv[]) 426 { 427 int ch, n, reload = 1; 428 429 while ((ch = getopt(argc, argv, 430 #ifdef LIBWRAP 431 "dl" 432 #else 433 "d" 434 #endif 435 )) != -1) 436 switch(ch) { 437 case 'd': 438 debug = 1; 439 options |= SO_DEBUG; 440 break; 441 #ifdef LIBWRAP 442 case 'l': 443 lflag = 1; 444 break; 445 #endif 446 case '?': 447 default: 448 usage(); 449 } 450 argc -= optind; 451 argv += optind; 452 453 if (argc > 0) 454 CONFIG = argv[0]; 455 456 if (!debug) 457 daemon(0, 0); 458 openlog("inetd", LOG_PID | LOG_NOWAIT, LOG_DAEMON); 459 pidfile(NULL); 460 461 kq = kqueue(); 462 if (kq < 0) { 463 syslog(LOG_ERR, "kqueue: %m"); 464 return (EXIT_FAILURE); 465 } 466 467 if (getrlimit(RLIMIT_NOFILE, &rlim_ofile) < 0) { 468 syslog(LOG_ERR, "getrlimit: %m"); 469 } else { 470 rlim_ofile_cur = rlim_ofile.rlim_cur; 471 if (rlim_ofile_cur == RLIM_INFINITY) /* ! */ 472 rlim_ofile_cur = OPEN_MAX; 473 } 474 475 for (n = 0; n < (int)A_CNT(my_signals); n++) { 476 int signum; 477 478 signum = my_signals[n]; 479 if (signum != SIGCHLD) 480 (void) signal(signum, SIG_IGN); 481 482 if (signum != SIGPIPE) { 483 struct kevent *ev; 484 485 ev = allocchange(); 486 EV_SET(ev, signum, EVFILT_SIGNAL, EV_ADD | EV_ENABLE, 487 0, 0, 0); 488 } 489 } 490 491 for (;;) { 492 int ctrl; 493 struct kevent eventbuf[64], *ev; 494 struct servtab *sep; 495 496 if (reload) { 497 reload = 0; 498 config(); 499 } 500 501 n = my_kevent(changebuf, changes, eventbuf, A_CNT(eventbuf)); 502 changes = 0; 503 504 for (ev = eventbuf; n > 0; ev++, n--) { 505 if (ev->filter == EVFILT_SIGNAL) { 506 switch (ev->ident) { 507 case SIGALRM: 508 retry(); 509 break; 510 case SIGCHLD: 511 reapchild(); 512 break; 513 case SIGTERM: 514 case SIGINT: 515 goaway(); 516 break; 517 case SIGHUP: 518 reload = 1; 519 break; 520 } 521 continue; 522 } 523 if (ev->filter != EVFILT_READ) 524 continue; 525 sep = (struct servtab *)ev->udata; 526 /* Paranoia */ 527 if ((int)ev->ident != sep->se_fd) 528 continue; 529 if (debug) 530 fprintf(stderr, "someone wants %s\n", 531 sep->se_service); 532 if (!sep->se_wait && sep->se_socktype == SOCK_STREAM) { 533 /* XXX here do the libwrap check-before-accept*/ 534 ctrl = accept(sep->se_fd, NULL, NULL); 535 if (debug) 536 fprintf(stderr, "accept, ctrl %d\n", 537 ctrl); 538 if (ctrl < 0) { 539 if (errno != EINTR) 540 syslog(LOG_WARNING, 541 "accept (for %s): %m", 542 sep->se_service); 543 continue; 544 } 545 } else 546 ctrl = sep->se_fd; 547 spawn(sep, ctrl); 548 } 549 } 550 } 551 552 static void 553 spawn(struct servtab *sep, int ctrl) 554 { 555 int dofork; 556 pid_t pid; 557 558 pid = 0; 559 #ifdef LIBWRAP_INTERNAL 560 dofork = 1; 561 #else 562 dofork = (sep->se_bi == 0 || sep->se_bi->bi_fork); 563 #endif 564 if (dofork) { 565 if (sep->se_count++ == 0) 566 (void)gettimeofday(&sep->se_time, NULL); 567 else if (sep->se_count >= sep->se_max) { 568 struct timeval now; 569 570 (void)gettimeofday(&now, NULL); 571 if (now.tv_sec - sep->se_time.tv_sec > CNT_INTVL) { 572 sep->se_time = now; 573 sep->se_count = 1; 574 } else { 575 syslog(LOG_ERR, 576 "%s/%s max spawn rate (%d in %d seconds) " 577 "exceeded; service not started", 578 sep->se_service, sep->se_proto, 579 sep->se_max, CNT_INTVL); 580 if (!sep->se_wait && sep->se_socktype == 581 SOCK_STREAM) 582 close(ctrl); 583 close_sep(sep); 584 if (!timingout) { 585 timingout = 1; 586 alarm(RETRYTIME); 587 } 588 return; 589 } 590 } 591 pid = fork(); 592 if (pid < 0) { 593 syslog(LOG_ERR, "fork: %m"); 594 if (!sep->se_wait && sep->se_socktype == SOCK_STREAM) 595 close(ctrl); 596 sleep(1); 597 return; 598 } 599 if (pid != 0 && sep->se_wait) { 600 struct kevent *ev; 601 602 sep->se_wait = pid; 603 ev = allocchange(); 604 EV_SET(ev, sep->se_fd, EVFILT_READ, 605 EV_DELETE, 0, 0, 0); 606 } 607 if (pid == 0) { 608 size_t n; 609 610 for (n = 0; n < A_CNT(my_signals); n++) 611 (void) signal(my_signals[n], SIG_DFL); 612 if (debug) 613 setsid(); 614 } 615 } 616 if (pid == 0) { 617 run_service(ctrl, sep, dofork); 618 if (dofork) 619 exit(0); 620 } 621 if (!sep->se_wait && sep->se_socktype == SOCK_STREAM) 622 close(ctrl); 623 } 624 625 static void 626 run_service(int ctrl, struct servtab *sep, int didfork) 627 { 628 struct passwd *pwd; 629 struct group *grp = NULL; /* XXX gcc */ 630 char buf[NI_MAXSERV]; 631 struct servtab *s; 632 #ifdef LIBWRAP 633 char abuf[BUFSIZ]; 634 struct request_info req; 635 int denied; 636 char *service = NULL; /* XXX gcc */ 637 #endif 638 639 #ifdef LIBWRAP 640 #ifndef LIBWRAP_INTERNAL 641 if (sep->se_bi == 0) 642 #endif 643 if (!sep->se_wait && sep->se_socktype == SOCK_STREAM) { 644 request_init(&req, RQ_DAEMON, sep->se_argv[0] ? 645 sep->se_argv[0] : sep->se_service, RQ_FILE, ctrl, NULL); 646 fromhost(&req); 647 denied = !hosts_access(&req); 648 if (denied || lflag) { 649 if (getnameinfo(&sep->se_ctrladdr, 650 (socklen_t)sep->se_ctrladdr.sa_len, NULL, 0, 651 buf, sizeof(buf), 0) != 0) { 652 /* shouldn't happen */ 653 (void)snprintf(buf, sizeof buf, "%d", 654 ntohs(sep->se_ctrladdr_in.sin_port)); 655 } 656 service = buf; 657 if (req.client->sin) { 658 sockaddr_snprintf(abuf, sizeof(abuf), "%a", 659 req.client->sin); 660 } else { 661 strcpy(abuf, "(null)"); 662 } 663 } 664 if (denied) { 665 syslog(deny_severity, 666 "refused connection from %.500s(%s), service %s (%s)", 667 eval_client(&req), abuf, service, sep->se_proto); 668 goto reject; 669 } 670 if (lflag) { 671 syslog(allow_severity, 672 "connection from %.500s(%s), service %s (%s)", 673 eval_client(&req), abuf, service, sep->se_proto); 674 } 675 } 676 #endif /* LIBWRAP */ 677 678 if (sep->se_bi) { 679 if (didfork) { 680 for (s = servtab; s; s = s->se_next) 681 if (s->se_fd != -1 && s->se_fd != ctrl) { 682 close(s->se_fd); 683 s->se_fd = -1; 684 } 685 } 686 (*sep->se_bi->bi_fn)(ctrl, sep); 687 } else { 688 if ((pwd = getpwnam(sep->se_user)) == NULL) { 689 syslog(LOG_ERR, "%s/%s: %s: No such user", 690 sep->se_service, sep->se_proto, sep->se_user); 691 goto reject; 692 } 693 if (sep->se_group && 694 (grp = getgrnam(sep->se_group)) == NULL) { 695 syslog(LOG_ERR, "%s/%s: %s: No such group", 696 sep->se_service, sep->se_proto, sep->se_group); 697 goto reject; 698 } 699 if (pwd->pw_uid) { 700 if (sep->se_group) 701 pwd->pw_gid = grp->gr_gid; 702 if (setgid(pwd->pw_gid) < 0) { 703 syslog(LOG_ERR, 704 "%s/%s: can't set gid %d: %m", sep->se_service, 705 sep->se_proto, pwd->pw_gid); 706 goto reject; 707 } 708 (void) initgroups(pwd->pw_name, 709 pwd->pw_gid); 710 if (setuid(pwd->pw_uid) < 0) { 711 syslog(LOG_ERR, 712 "%s/%s: can't set uid %d: %m", sep->se_service, 713 sep->se_proto, pwd->pw_uid); 714 goto reject; 715 } 716 } else if (sep->se_group) { 717 (void) setgid((gid_t)grp->gr_gid); 718 } 719 if (debug) 720 fprintf(stderr, "%d execl %s\n", 721 getpid(), sep->se_server); 722 /* Set our control descriptor to not close-on-exec... */ 723 if (fcntl(ctrl, F_SETFD, 0) < 0) 724 syslog(LOG_ERR, "fcntl (%d, F_SETFD, 0): %m", ctrl); 725 /* ...and dup it to stdin, stdout, and stderr. */ 726 if (ctrl != 0) { 727 dup2(ctrl, 0); 728 close(ctrl); 729 ctrl = 0; 730 } 731 dup2(0, 1); 732 dup2(0, 2); 733 if (rlim_ofile.rlim_cur != rlim_ofile_cur && 734 setrlimit(RLIMIT_NOFILE, &rlim_ofile) < 0) 735 syslog(LOG_ERR, "setrlimit: %m"); 736 execv(sep->se_server, sep->se_argv); 737 syslog(LOG_ERR, "cannot execute %s: %m", sep->se_server); 738 reject: 739 if (sep->se_socktype != SOCK_STREAM) 740 recv(ctrl, buf, sizeof (buf), 0); 741 _exit(1); 742 } 743 } 744 745 static void 746 reapchild(void) 747 { 748 int status; 749 pid_t pid; 750 struct servtab *sep; 751 752 for (;;) { 753 pid = wait3(&status, WNOHANG, NULL); 754 if (pid <= 0) 755 break; 756 if (debug) 757 (void) fprintf(stderr, "%d reaped, status %#x\n", 758 pid, status); 759 for (sep = servtab; sep != NULL; sep = sep->se_next) 760 if (sep->se_wait == pid) { 761 struct kevent *ev; 762 763 if (WIFEXITED(status) && WEXITSTATUS(status)) 764 syslog(LOG_WARNING, 765 "%s: exit status 0x%x", 766 sep->se_server, WEXITSTATUS(status)); 767 else if (WIFSIGNALED(status)) 768 syslog(LOG_WARNING, 769 "%s: exit signal 0x%x", 770 sep->se_server, WTERMSIG(status)); 771 sep->se_wait = 1; 772 ev = allocchange(); 773 EV_SET(ev, sep->se_fd, EVFILT_READ, 774 EV_ADD | EV_ENABLE, 0, 0, (intptr_t)sep); 775 if (debug) 776 fprintf(stderr, "restored %s, fd %d\n", 777 sep->se_service, sep->se_fd); 778 } 779 } 780 } 781 782 static void 783 config(void) 784 { 785 struct servtab *sep, *cp, **sepp; 786 size_t n; 787 788 if (!setconfig()) { 789 syslog(LOG_ERR, "%s: %m", CONFIG); 790 return; 791 } 792 for (sep = servtab; sep != NULL; sep = sep->se_next) 793 sep->se_checked = 0; 794 while ((cp = getconfigent()) != NULL) { 795 for (sep = servtab; sep != NULL; sep = sep->se_next) 796 if (strcmp(sep->se_service, cp->se_service) == 0 && 797 strcmp(sep->se_hostaddr, cp->se_hostaddr) == 0 && 798 strcmp(sep->se_proto, cp->se_proto) == 0 && 799 ISMUX(sep) == ISMUX(cp)) 800 break; 801 if (sep != NULL) { 802 int i; 803 804 #define SWAP(type, a, b) {type c = a; a = b; b = c;} 805 806 /* 807 * sep->se_wait may be holding the pid of a daemon 808 * that we're waiting for. If so, don't overwrite 809 * it unless the config file explicitly says don't 810 * wait. 811 */ 812 if (cp->se_bi == 0 && 813 (sep->se_wait == 1 || cp->se_wait == 0)) 814 sep->se_wait = cp->se_wait; 815 SWAP(char *, sep->se_user, cp->se_user); 816 SWAP(char *, sep->se_group, cp->se_group); 817 SWAP(char *, sep->se_server, cp->se_server); 818 for (i = 0; i < MAXARGV; i++) 819 SWAP(char *, sep->se_argv[i], cp->se_argv[i]); 820 #ifdef IPSEC 821 SWAP(char *, sep->se_policy, cp->se_policy); 822 #endif 823 SWAP(int, cp->se_type, sep->se_type); 824 SWAP(int, cp->se_max, sep->se_max); 825 #undef SWAP 826 if (isrpcservice(sep)) 827 unregister_rpc(sep); 828 sep->se_rpcversl = cp->se_rpcversl; 829 sep->se_rpcversh = cp->se_rpcversh; 830 freeconfig(cp); 831 if (debug) 832 print_service("REDO", sep); 833 } else { 834 sep = enter(cp); 835 if (debug) 836 print_service("ADD ", sep); 837 } 838 sep->se_checked = 1; 839 840 switch (sep->se_family) { 841 case AF_LOCAL: 842 if (sep->se_fd != -1) 843 break; 844 n = strlen(sep->se_service); 845 if (n > sizeof(sep->se_ctrladdr_un.sun_path)) { 846 syslog(LOG_ERR, "%s: address too long", 847 sep->se_service); 848 sep->se_checked = 0; 849 continue; 850 } 851 (void)unlink(sep->se_service); 852 strncpy(sep->se_ctrladdr_un.sun_path, 853 sep->se_service, n); 854 sep->se_ctrladdr_un.sun_family = AF_LOCAL; 855 sep->se_ctrladdr_size = (int)(n + 856 sizeof(sep->se_ctrladdr_un) - 857 sizeof(sep->se_ctrladdr_un.sun_path)); 858 if (!ISMUX(sep)) 859 setup(sep); 860 break; 861 case AF_INET: 862 #ifdef INET6 863 case AF_INET6: 864 #endif 865 { 866 struct addrinfo hints, *res; 867 char *host; 868 const char *port; 869 int error; 870 int s; 871 872 /* check if the family is supported */ 873 s = socket(sep->se_family, SOCK_DGRAM, 0); 874 if (s < 0) { 875 syslog(LOG_WARNING, 876 "%s/%s: %s: the address family is not " 877 "supported by the kernel", 878 sep->se_service, sep->se_proto, 879 sep->se_hostaddr); 880 sep->se_checked = 0; 881 continue; 882 } 883 close(s); 884 885 memset(&hints, 0, sizeof(hints)); 886 hints.ai_family = sep->se_family; 887 hints.ai_socktype = sep->se_socktype; 888 hints.ai_flags = AI_PASSIVE; 889 if (!strcmp(sep->se_hostaddr, "*")) 890 host = NULL; 891 else 892 host = sep->se_hostaddr; 893 if (isrpcservice(sep) || ISMUX(sep)) 894 port = "0"; 895 else 896 port = sep->se_service; 897 error = getaddrinfo(host, port, &hints, &res); 898 if (error) { 899 if (error == EAI_SERVICE) { 900 /* gai_strerror not friendly enough */ 901 syslog(LOG_WARNING, "%s/%s: " 902 "unknown service", 903 sep->se_service, sep->se_proto); 904 } else { 905 syslog(LOG_ERR, "%s/%s: %s: %s", 906 sep->se_service, sep->se_proto, 907 sep->se_hostaddr, 908 gai_strerror(error)); 909 } 910 sep->se_checked = 0; 911 continue; 912 } 913 if (res->ai_next) { 914 syslog(LOG_ERR, 915 "%s/%s: %s: resolved to multiple addr", 916 sep->se_service, sep->se_proto, 917 sep->se_hostaddr); 918 sep->se_checked = 0; 919 freeaddrinfo(res); 920 continue; 921 } 922 memcpy(&sep->se_ctrladdr, res->ai_addr, 923 res->ai_addrlen); 924 if (ISMUX(sep)) { 925 sep->se_fd = -1; 926 freeaddrinfo(res); 927 continue; 928 } 929 sep->se_ctrladdr_size = res->ai_addrlen; 930 freeaddrinfo(res); 931 #ifdef RPC 932 if (isrpcservice(sep)) { 933 struct rpcent *rp; 934 935 sep->se_rpcprog = atoi(sep->se_service); 936 if (sep->se_rpcprog == 0) { 937 rp = getrpcbyname(sep->se_service); 938 if (rp == 0) { 939 syslog(LOG_ERR, 940 "%s/%s: unknown service", 941 sep->se_service, 942 sep->se_proto); 943 sep->se_checked = 0; 944 continue; 945 } 946 sep->se_rpcprog = rp->r_number; 947 } 948 if (sep->se_fd == -1 && !ISMUX(sep)) 949 setup(sep); 950 if (sep->se_fd != -1) 951 register_rpc(sep); 952 } else 953 #endif 954 { 955 if (sep->se_fd >= 0) 956 close_sep(sep); 957 if (sep->se_fd == -1 && !ISMUX(sep)) 958 setup(sep); 959 } 960 } 961 } 962 } 963 endconfig(); 964 /* 965 * Purge anything not looked at above. 966 */ 967 sepp = &servtab; 968 while ((sep = *sepp) != NULL) { 969 if (sep->se_checked) { 970 sepp = &sep->se_next; 971 continue; 972 } 973 *sepp = sep->se_next; 974 if (sep->se_fd >= 0) 975 close_sep(sep); 976 if (isrpcservice(sep)) 977 unregister_rpc(sep); 978 if (sep->se_family == AF_LOCAL) 979 (void)unlink(sep->se_service); 980 if (debug) 981 print_service("FREE", sep); 982 freeconfig(sep); 983 free(sep); 984 } 985 } 986 987 static void 988 retry(void) 989 { 990 struct servtab *sep; 991 992 timingout = 0; 993 for (sep = servtab; sep != NULL; sep = sep->se_next) { 994 if (sep->se_fd == -1 && !ISMUX(sep)) { 995 switch (sep->se_family) { 996 case AF_LOCAL: 997 case AF_INET: 998 #ifdef INET6 999 case AF_INET6: 1000 #endif 1001 setup(sep); 1002 if (sep->se_fd >= 0 && isrpcservice(sep)) 1003 register_rpc(sep); 1004 break; 1005 } 1006 } 1007 } 1008 } 1009 1010 static void 1011 goaway(void) 1012 { 1013 struct servtab *sep; 1014 1015 for (sep = servtab; sep != NULL; sep = sep->se_next) { 1016 if (sep->se_fd == -1) 1017 continue; 1018 1019 switch (sep->se_family) { 1020 case AF_LOCAL: 1021 (void)unlink(sep->se_service); 1022 break; 1023 case AF_INET: 1024 #ifdef INET6 1025 case AF_INET6: 1026 #endif 1027 if (sep->se_wait == 1 && isrpcservice(sep)) 1028 unregister_rpc(sep); 1029 break; 1030 } 1031 (void)close(sep->se_fd); 1032 sep->se_fd = -1; 1033 } 1034 exit(0); 1035 } 1036 1037 static void 1038 setup(struct servtab *sep) 1039 { 1040 int on = 1; 1041 #ifdef INET6 1042 int off = 0; 1043 #endif 1044 struct kevent *ev; 1045 1046 if ((sep->se_fd = socket(sep->se_family, sep->se_socktype, 0)) < 0) { 1047 if (debug) 1048 fprintf(stderr, "socket failed on %s/%s: %s\n", 1049 sep->se_service, sep->se_proto, strerror(errno)); 1050 syslog(LOG_ERR, "%s/%s: socket: %m", 1051 sep->se_service, sep->se_proto); 1052 return; 1053 } 1054 /* Set all listening sockets to close-on-exec. */ 1055 if (fcntl(sep->se_fd, F_SETFD, FD_CLOEXEC) < 0) { 1056 syslog(LOG_ERR, "%s/%s: fcntl(F_SETFD, FD_CLOEXEC): %m", 1057 sep->se_service, sep->se_proto); 1058 close(sep->se_fd); 1059 sep->se_fd = -1; 1060 return; 1061 } 1062 1063 #define turnon(fd, opt) \ 1064 setsockopt(fd, SOL_SOCKET, opt, &on, (socklen_t)sizeof(on)) 1065 if (strcmp(sep->se_proto, "tcp") == 0 && (options & SO_DEBUG) && 1066 turnon(sep->se_fd, SO_DEBUG) < 0) 1067 syslog(LOG_ERR, "setsockopt (SO_DEBUG): %m"); 1068 if (turnon(sep->se_fd, SO_REUSEADDR) < 0) 1069 syslog(LOG_ERR, "setsockopt (SO_REUSEADDR): %m"); 1070 #undef turnon 1071 1072 /* Set the socket buffer sizes, if specified. */ 1073 if (sep->se_sndbuf != 0 && setsockopt(sep->se_fd, SOL_SOCKET, 1074 SO_SNDBUF, &sep->se_sndbuf, (socklen_t)sizeof(sep->se_sndbuf)) < 0) 1075 syslog(LOG_ERR, "setsockopt (SO_SNDBUF %d): %m", 1076 sep->se_sndbuf); 1077 if (sep->se_rcvbuf != 0 && setsockopt(sep->se_fd, SOL_SOCKET, 1078 SO_RCVBUF, &sep->se_rcvbuf, (socklen_t)sizeof(sep->se_rcvbuf)) < 0) 1079 syslog(LOG_ERR, "setsockopt (SO_RCVBUF %d): %m", 1080 sep->se_rcvbuf); 1081 #ifdef INET6 1082 if (sep->se_family == AF_INET6) { 1083 int *v; 1084 v = (sep->se_type == FAITH_TYPE) ? &on : &off; 1085 if (setsockopt(sep->se_fd, IPPROTO_IPV6, IPV6_FAITH, 1086 v, (socklen_t)sizeof(*v)) < 0) 1087 syslog(LOG_ERR, "setsockopt (IPV6_FAITH): %m"); 1088 } 1089 #endif 1090 #ifdef IPSEC 1091 if (ipsecsetup(sep->se_family, sep->se_fd, sep->se_policy) < 0 && 1092 sep->se_policy) { 1093 syslog(LOG_ERR, "%s/%s: ipsec setup failed", 1094 sep->se_service, sep->se_proto); 1095 (void)close(sep->se_fd); 1096 sep->se_fd = -1; 1097 return; 1098 } 1099 #endif 1100 1101 if (bind(sep->se_fd, &sep->se_ctrladdr, 1102 (socklen_t)sep->se_ctrladdr_size) < 0) { 1103 if (debug) 1104 fprintf(stderr, "bind failed on %s/%s: %s\n", 1105 sep->se_service, sep->se_proto, strerror(errno)); 1106 syslog(LOG_ERR, "%s/%s: bind: %m", 1107 sep->se_service, sep->se_proto); 1108 (void) close(sep->se_fd); 1109 sep->se_fd = -1; 1110 if (!timingout) { 1111 timingout = 1; 1112 alarm(RETRYTIME); 1113 } 1114 return; 1115 } 1116 if (sep->se_socktype == SOCK_STREAM) 1117 listen(sep->se_fd, 10); 1118 1119 /* Set the accept filter, if specified. To be done after listen.*/ 1120 if (sep->se_accf.af_name[0] != 0 && setsockopt(sep->se_fd, SOL_SOCKET, 1121 SO_ACCEPTFILTER, &sep->se_accf, 1122 (socklen_t)sizeof(sep->se_accf)) < 0) 1123 syslog(LOG_ERR, "setsockopt(SO_ACCEPTFILTER %s): %m", 1124 sep->se_accf.af_name); 1125 1126 ev = allocchange(); 1127 EV_SET(ev, sep->se_fd, EVFILT_READ, EV_ADD | EV_ENABLE, 0, 0, 1128 (intptr_t)sep); 1129 if (sep->se_fd > maxsock) { 1130 maxsock = sep->se_fd; 1131 if (maxsock > (int)(rlim_ofile_cur - FD_MARGIN)) 1132 bump_nofile(); 1133 } 1134 if (debug) 1135 fprintf(stderr, "registered %s on %d\n", 1136 sep->se_server, sep->se_fd); 1137 } 1138 1139 /* 1140 * Finish with a service and its socket. 1141 */ 1142 static void 1143 close_sep(struct servtab *sep) 1144 { 1145 if (sep->se_fd >= 0) { 1146 (void) close(sep->se_fd); 1147 sep->se_fd = -1; 1148 } 1149 sep->se_count = 0; 1150 } 1151 1152 static void 1153 register_rpc(struct servtab *sep) 1154 { 1155 #ifdef RPC 1156 struct netbuf nbuf; 1157 struct sockaddr_storage ss; 1158 struct netconfig *nconf; 1159 socklen_t socklen; 1160 int n; 1161 1162 if ((nconf = getnetconfigent(sep->se_proto+4)) == NULL) { 1163 syslog(LOG_ERR, "%s: getnetconfigent failed", 1164 sep->se_proto); 1165 return; 1166 } 1167 socklen = sizeof ss; 1168 if (getsockname(sep->se_fd, (struct sockaddr *)(void *)&ss, &socklen) < 0) { 1169 syslog(LOG_ERR, "%s/%s: getsockname: %m", 1170 sep->se_service, sep->se_proto); 1171 return; 1172 } 1173 1174 nbuf.buf = &ss; 1175 nbuf.len = ss.ss_len; 1176 nbuf.maxlen = sizeof (struct sockaddr_storage); 1177 for (n = sep->se_rpcversl; n <= sep->se_rpcversh; n++) { 1178 if (debug) 1179 fprintf(stderr, "rpcb_set: %u %d %s %s\n", 1180 sep->se_rpcprog, n, nconf->nc_netid, 1181 taddr2uaddr(nconf, &nbuf)); 1182 (void)rpcb_unset((unsigned int)sep->se_rpcprog, (unsigned int)n, nconf); 1183 if (!rpcb_set((unsigned int)sep->se_rpcprog, (unsigned int)n, nconf, &nbuf)) 1184 syslog(LOG_ERR, "rpcb_set: %u %d %s %s%s", 1185 sep->se_rpcprog, n, nconf->nc_netid, 1186 taddr2uaddr(nconf, &nbuf), clnt_spcreateerror("")); 1187 } 1188 #endif /* RPC */ 1189 } 1190 1191 static void 1192 unregister_rpc(struct servtab *sep) 1193 { 1194 #ifdef RPC 1195 int n; 1196 struct netconfig *nconf; 1197 1198 if ((nconf = getnetconfigent(sep->se_proto+4)) == NULL) { 1199 syslog(LOG_ERR, "%s: getnetconfigent failed", 1200 sep->se_proto); 1201 return; 1202 } 1203 1204 for (n = sep->se_rpcversl; n <= sep->se_rpcversh; n++) { 1205 if (debug) 1206 fprintf(stderr, "rpcb_unset(%u, %d, %s)\n", 1207 sep->se_rpcprog, n, nconf->nc_netid); 1208 if (!rpcb_unset((unsigned int)sep->se_rpcprog, (unsigned int)n, nconf)) 1209 syslog(LOG_ERR, "rpcb_unset(%u, %d, %s) failed\n", 1210 sep->se_rpcprog, n, nconf->nc_netid); 1211 } 1212 #endif /* RPC */ 1213 } 1214 1215 1216 static struct servtab * 1217 enter(struct servtab *cp) 1218 { 1219 struct servtab *sep; 1220 1221 sep = malloc(sizeof (*sep)); 1222 if (sep == NULL) { 1223 syslog(LOG_ERR, "Out of memory."); 1224 exit(1); 1225 } 1226 *sep = *cp; 1227 sep->se_fd = -1; 1228 sep->se_rpcprog = -1; 1229 sep->se_next = servtab; 1230 servtab = sep; 1231 return (sep); 1232 } 1233 1234 FILE *fconfig = NULL; 1235 struct servtab serv; 1236 char line[LINE_MAX]; 1237 char *defhost; 1238 #ifdef IPSEC 1239 static char *policy = NULL; 1240 #endif 1241 1242 static int 1243 setconfig(void) 1244 { 1245 if (defhost) 1246 free(defhost); 1247 defhost = newstr("*"); 1248 #ifdef IPSEC 1249 if (policy) 1250 free(policy); 1251 policy = NULL; 1252 #endif 1253 if (fconfig != NULL) { 1254 fseek(fconfig, 0L, SEEK_SET); 1255 return (1); 1256 } 1257 fconfig = fopen(CONFIG, "r"); 1258 return (fconfig != NULL); 1259 } 1260 1261 static void 1262 endconfig(void) 1263 { 1264 if (fconfig != NULL) { 1265 (void) fclose(fconfig); 1266 fconfig = NULL; 1267 } 1268 if (defhost != NULL) { 1269 free(defhost); 1270 defhost = NULL; 1271 } 1272 } 1273 1274 static struct servtab * 1275 getconfigent(void) 1276 { 1277 struct servtab *sep = &serv; 1278 int argc, val; 1279 char *cp, *cp0, *arg, *buf0, *buf1, *sz0, *sz1; 1280 static char TCPMUX_TOKEN[] = "tcpmux/"; 1281 #define MUX_LEN (sizeof(TCPMUX_TOKEN)-1) 1282 char *hostdelim; 1283 1284 more: 1285 while ((cp = nextline(fconfig)) != NULL) { 1286 #ifdef IPSEC 1287 /* lines starting with #@ is not a comment, but the policy */ 1288 if (cp[0] == '#' && cp[1] == '@') { 1289 char *p; 1290 for (p = cp + 2; p && *p && isspace((unsigned char)*p); p++) 1291 ; 1292 if (*p == '\0') { 1293 if (policy) 1294 free(policy); 1295 policy = NULL; 1296 } else { 1297 if (ipsecsetup_test(p) < 0) { 1298 syslog(LOG_ERR, 1299 "%s: invalid ipsec policy \"%s\"", 1300 CONFIG, p); 1301 exit(1); 1302 } else { 1303 if (policy) 1304 free(policy); 1305 policy = newstr(p); 1306 } 1307 } 1308 } 1309 #endif 1310 if (*cp == '#' || *cp == '\0') 1311 continue; 1312 break; 1313 } 1314 if (cp == NULL) 1315 return (NULL); 1316 /* 1317 * clear the static buffer, since some fields (se_ctrladdr, 1318 * for example) don't get initialized here. 1319 */ 1320 memset(sep, 0, sizeof *sep); 1321 arg = skip(&cp); 1322 if (cp == NULL) { 1323 /* got an empty line containing just blanks/tabs. */ 1324 goto more; 1325 } 1326 /* Check for a host name. */ 1327 hostdelim = strrchr(arg, ':'); 1328 if (hostdelim) { 1329 *hostdelim = '\0'; 1330 if (arg[0] == '[' && hostdelim > arg && hostdelim[-1] == ']') { 1331 hostdelim[-1] = '\0'; 1332 sep->se_hostaddr = newstr(arg + 1); 1333 } else 1334 sep->se_hostaddr = newstr(arg); 1335 arg = hostdelim + 1; 1336 /* 1337 * If the line is of the form `host:', then just change the 1338 * default host for the following lines. 1339 */ 1340 if (*arg == '\0') { 1341 arg = skip(&cp); 1342 if (cp == NULL) { 1343 free(defhost); 1344 defhost = sep->se_hostaddr; 1345 goto more; 1346 } 1347 } 1348 } else 1349 sep->se_hostaddr = newstr(defhost); 1350 if (strncmp(arg, TCPMUX_TOKEN, MUX_LEN) == 0) { 1351 char *c = arg + MUX_LEN; 1352 if (*c == '+') { 1353 sep->se_type = MUXPLUS_TYPE; 1354 c++; 1355 } else 1356 sep->se_type = MUX_TYPE; 1357 sep->se_service = newstr(c); 1358 } else { 1359 sep->se_service = newstr(arg); 1360 sep->se_type = NORM_TYPE; 1361 } 1362 1363 arg = sskip(&cp); 1364 if (strncmp(arg, "stream", sizeof("stream") - 1) == 0) { 1365 char *accf, *accf_arg; 1366 1367 sep->se_socktype = SOCK_STREAM; 1368 1369 /* one and only one accept filter */ 1370 accf = index(arg, ':'); 1371 if (accf) { 1372 if (accf != rindex(arg, ':') || /* more than one */ 1373 *(accf + 1) == '\0') { /* nothing beyond */ 1374 sep->se_socktype = -1; 1375 } else { 1376 accf++; /* skip delimiter */ 1377 strncpy(sep->se_accf.af_name, accf, 1378 sizeof(sep->se_accf.af_name)); 1379 accf_arg = index(accf, ','); 1380 if (accf_arg) { /* zero or one arg, no more */ 1381 if ((rindex(accf, ',') != accf_arg)) { 1382 sep->se_socktype = -1; 1383 } else { 1384 accf_arg++; 1385 strncpy(sep->se_accf.af_arg, 1386 accf_arg, 1387 sizeof(sep->se_accf.af_arg)); 1388 } 1389 } 1390 } 1391 } 1392 } 1393 1394 else if (strcmp(arg, "dgram") == 0) 1395 sep->se_socktype = SOCK_DGRAM; 1396 else if (strcmp(arg, "rdm") == 0) 1397 sep->se_socktype = SOCK_RDM; 1398 else if (strcmp(arg, "seqpacket") == 0) 1399 sep->se_socktype = SOCK_SEQPACKET; 1400 else if (strcmp(arg, "raw") == 0) 1401 sep->se_socktype = SOCK_RAW; 1402 else 1403 sep->se_socktype = -1; 1404 1405 arg = sskip(&cp); 1406 if (sep->se_type == NORM_TYPE && 1407 strncmp(arg, "faith/", strlen("faith/")) == 0) { 1408 arg += strlen("faith/"); 1409 sep->se_type = FAITH_TYPE; 1410 } 1411 sep->se_proto = newstr(arg); 1412 1413 #define MALFORMED(arg) \ 1414 do { \ 1415 syslog(LOG_ERR, "%s: malformed buffer size option `%s'", \ 1416 sep->se_service, (arg)); \ 1417 goto more; \ 1418 /*NOTREACHED*/ \ 1419 } while (/*CONSTCOND*/0) 1420 1421 #define GETVAL(arg) \ 1422 do { \ 1423 if (!isdigit((unsigned char)*(arg))) \ 1424 MALFORMED(arg); \ 1425 val = (int)strtol((arg), &cp0, 10); \ 1426 if (cp0 != NULL) { \ 1427 if (cp0[1] != '\0') \ 1428 MALFORMED((arg)); \ 1429 if (cp0[0] == 'k') \ 1430 val *= 1024; \ 1431 if (cp0[0] == 'm') \ 1432 val *= 1024 * 1024; \ 1433 } \ 1434 if (val < 1) { \ 1435 syslog(LOG_ERR, "%s: invalid buffer size `%s'", \ 1436 sep->se_service, (arg)); \ 1437 goto more; \ 1438 } \ 1439 /*NOTREACHED*/ \ 1440 } while (/*CONSTCOND*/0) 1441 1442 #define ASSIGN(arg) \ 1443 do { \ 1444 if (strcmp((arg), "sndbuf") == 0) \ 1445 sep->se_sndbuf = val; \ 1446 else if (strcmp((arg), "rcvbuf") == 0) \ 1447 sep->se_rcvbuf = val; \ 1448 else \ 1449 MALFORMED((arg)); \ 1450 } while (/*CONSTCOND*/0) 1451 1452 /* 1453 * Extract the send and receive buffer sizes before parsing 1454 * the protocol. 1455 */ 1456 sep->se_sndbuf = sep->se_rcvbuf = 0; 1457 buf0 = buf1 = sz0 = sz1 = NULL; 1458 if ((buf0 = strchr(sep->se_proto, ',')) != NULL) { 1459 /* Not meaningful for Tcpmux services. */ 1460 if (ISMUX(sep)) { 1461 syslog(LOG_ERR, "%s: can't specify buffer sizes for " 1462 "tcpmux services", sep->se_service); 1463 goto more; 1464 } 1465 1466 /* Skip the , */ 1467 *buf0++ = '\0'; 1468 1469 /* Check to see if another socket buffer size was specified. */ 1470 if ((buf1 = strchr(buf0, ',')) != NULL) { 1471 /* Skip the , */ 1472 *buf1++ = '\0'; 1473 1474 /* Make sure a 3rd one wasn't specified. */ 1475 if (strchr(buf1, ',') != NULL) { 1476 syslog(LOG_ERR, "%s: too many buffer sizes", 1477 sep->se_service); 1478 goto more; 1479 } 1480 1481 /* Locate the size. */ 1482 if ((sz1 = strchr(buf1, '=')) == NULL) 1483 MALFORMED(buf1); 1484 1485 /* Skip the = */ 1486 *sz1++ = '\0'; 1487 } 1488 1489 /* Locate the size. */ 1490 if ((sz0 = strchr(buf0, '=')) == NULL) 1491 MALFORMED(buf0); 1492 1493 /* Skip the = */ 1494 *sz0++ = '\0'; 1495 1496 GETVAL(sz0); 1497 ASSIGN(buf0); 1498 1499 if (buf1 != NULL) { 1500 GETVAL(sz1); 1501 ASSIGN(buf1); 1502 } 1503 } 1504 1505 #undef ASSIGN 1506 #undef GETVAL 1507 #undef MALFORMED 1508 1509 if (strcmp(sep->se_proto, "unix") == 0) { 1510 sep->se_family = AF_LOCAL; 1511 } else { 1512 val = (int)strlen(sep->se_proto); 1513 if (!val) { 1514 syslog(LOG_ERR, "%s: invalid protocol specified", 1515 sep->se_service); 1516 goto more; 1517 } 1518 val = sep->se_proto[val - 1]; 1519 switch (val) { 1520 case '4': /*tcp4 or udp4*/ 1521 sep->se_family = AF_INET; 1522 break; 1523 #ifdef INET6 1524 case '6': /*tcp6 or udp6*/ 1525 sep->se_family = AF_INET6; 1526 break; 1527 #endif 1528 default: 1529 sep->se_family = AF_INET; /*will become AF_INET6*/ 1530 break; 1531 } 1532 if (strncmp(sep->se_proto, "rpc/", 4) == 0) { 1533 #ifdef RPC 1534 char *cp1, *ccp; 1535 cp1 = strchr(sep->se_service, '/'); 1536 if (cp1 == 0) { 1537 syslog(LOG_ERR, "%s: no rpc version", 1538 sep->se_service); 1539 goto more; 1540 } 1541 *cp1++ = '\0'; 1542 sep->se_rpcversl = sep->se_rpcversh = 1543 (int)strtol(cp1, &ccp, 0); 1544 if (ccp == cp1) { 1545 badafterall: 1546 syslog(LOG_ERR, "%s/%s: bad rpc version", 1547 sep->se_service, cp1); 1548 goto more; 1549 } 1550 if (*ccp == '-') { 1551 cp1 = ccp + 1; 1552 sep->se_rpcversh = (int)strtol(cp1, &ccp, 0); 1553 if (ccp == cp1) 1554 goto badafterall; 1555 } 1556 #else 1557 syslog(LOG_ERR, "%s: rpc services not suported", 1558 sep->se_service); 1559 goto more; 1560 #endif /* RPC */ 1561 } 1562 } 1563 arg = sskip(&cp); 1564 { 1565 char *cp1; 1566 if ((cp1 = strchr(arg, ':')) == NULL) 1567 cp1 = strchr(arg, '.'); 1568 if (cp1 != NULL) { 1569 *cp1++ = '\0'; 1570 sep->se_max = atoi(cp1); 1571 } else 1572 sep->se_max = TOOMANY; 1573 } 1574 sep->se_wait = strcmp(arg, "wait") == 0; 1575 if (ISMUX(sep)) { 1576 /* 1577 * Silently enforce "nowait" for TCPMUX services since 1578 * they don't have an assigned port to listen on. 1579 */ 1580 sep->se_wait = 0; 1581 1582 if (strncmp(sep->se_proto, "tcp", 3)) { 1583 syslog(LOG_ERR, 1584 "%s: bad protocol for tcpmux service %s", 1585 CONFIG, sep->se_service); 1586 goto more; 1587 } 1588 if (sep->se_socktype != SOCK_STREAM) { 1589 syslog(LOG_ERR, 1590 "%s: bad socket type for tcpmux service %s", 1591 CONFIG, sep->se_service); 1592 goto more; 1593 } 1594 } 1595 sep->se_user = newstr(sskip(&cp)); 1596 if ((sep->se_group = strchr(sep->se_user, ':')) != NULL) 1597 *sep->se_group++ = '\0'; 1598 else if ((sep->se_group = strchr(sep->se_user, '.')) != NULL) 1599 *sep->se_group++ = '\0'; 1600 1601 sep->se_server = newstr(sskip(&cp)); 1602 if (strcmp(sep->se_server, "internal") == 0) { 1603 struct biltin *bi; 1604 1605 for (bi = biltins; bi->bi_service; bi++) 1606 if (bi->bi_socktype == sep->se_socktype && 1607 strcmp(bi->bi_service, sep->se_service) == 0) 1608 break; 1609 if (bi->bi_service == 0) { 1610 syslog(LOG_ERR, "internal service %s unknown", 1611 sep->se_service); 1612 goto more; 1613 } 1614 sep->se_bi = bi; 1615 sep->se_wait = bi->bi_wait; 1616 } else 1617 sep->se_bi = NULL; 1618 argc = 0; 1619 for (arg = skip(&cp); cp; arg = skip(&cp)) { 1620 if (argc < MAXARGV) 1621 sep->se_argv[argc++] = newstr(arg); 1622 } 1623 while (argc <= MAXARGV) 1624 sep->se_argv[argc++] = NULL; 1625 #ifdef IPSEC 1626 sep->se_policy = policy ? newstr(policy) : NULL; 1627 #endif 1628 return (sep); 1629 } 1630 1631 static void 1632 freeconfig(struct servtab *cp) 1633 { 1634 int i; 1635 1636 if (cp->se_hostaddr) 1637 free(cp->se_hostaddr); 1638 if (cp->se_service) 1639 free(cp->se_service); 1640 if (cp->se_proto) 1641 free(cp->se_proto); 1642 if (cp->se_user) 1643 free(cp->se_user); 1644 /* Note: se_group is part of the newstr'ed se_user */ 1645 if (cp->se_server) 1646 free(cp->se_server); 1647 for (i = 0; i < MAXARGV; i++) 1648 if (cp->se_argv[i]) 1649 free(cp->se_argv[i]); 1650 #ifdef IPSEC 1651 if (cp->se_policy) 1652 free(cp->se_policy); 1653 #endif 1654 } 1655 1656 1657 /* 1658 * Safe skip - if skip returns null, log a syntax error in the 1659 * configuration file and exit. 1660 */ 1661 static char * 1662 sskip(char **cpp) 1663 { 1664 char *cp; 1665 1666 cp = skip(cpp); 1667 if (cp == NULL) { 1668 syslog(LOG_ERR, "%s: syntax error", CONFIG); 1669 exit(1); 1670 } 1671 return (cp); 1672 } 1673 1674 static char * 1675 skip(char **cpp) 1676 { 1677 char *cp = *cpp; 1678 char *start; 1679 char quote; 1680 1681 if (*cpp == NULL) 1682 return (NULL); 1683 1684 again: 1685 while (*cp == ' ' || *cp == '\t') 1686 cp++; 1687 if (*cp == '\0') { 1688 int c; 1689 1690 c = getc(fconfig); 1691 (void) ungetc(c, fconfig); 1692 if (c == ' ' || c == '\t') 1693 if ((cp = nextline(fconfig)) != NULL) 1694 goto again; 1695 *cpp = NULL; 1696 return (NULL); 1697 } 1698 start = cp; 1699 quote = '\0'; 1700 while (*cp && (quote || (*cp != ' ' && *cp != '\t'))) { 1701 if (*cp == '\'' || *cp == '"') { 1702 if (quote && *cp != quote) 1703 cp++; 1704 else { 1705 if (quote) 1706 quote = '\0'; 1707 else 1708 quote = *cp; 1709 memmove(cp, cp+1, strlen(cp)); 1710 } 1711 } else 1712 cp++; 1713 } 1714 if (*cp != '\0') 1715 *cp++ = '\0'; 1716 *cpp = cp; 1717 return (start); 1718 } 1719 1720 static char * 1721 nextline(FILE *fd) 1722 { 1723 char *cp; 1724 1725 if (fgets(line, (int)sizeof(line), fd) == NULL) 1726 return (NULL); 1727 cp = strchr(line, '\n'); 1728 if (cp) 1729 *cp = '\0'; 1730 return (line); 1731 } 1732 1733 static char * 1734 newstr(const char *cp) 1735 { 1736 char *dp; 1737 if ((dp = strdup((cp != NULL) ? cp : "")) != NULL) 1738 return (dp); 1739 syslog(LOG_ERR, "strdup: %m"); 1740 exit(1); 1741 /*NOTREACHED*/ 1742 } 1743 1744 static void 1745 inetd_setproctitle(char *a, int s) 1746 { 1747 socklen_t size; 1748 struct sockaddr_storage ss; 1749 char hbuf[NI_MAXHOST]; 1750 const char *hp; 1751 struct sockaddr *sa; 1752 1753 size = sizeof(ss); 1754 sa = (struct sockaddr *)(void *)&ss; 1755 if (getpeername(s, sa, &size) == 0) { 1756 if (getnameinfo(sa, size, hbuf, (socklen_t)sizeof(hbuf), NULL, 1757 0, niflags) != 0) 1758 hp = "?"; 1759 else 1760 hp = hbuf; 1761 setproctitle("-%s [%s]", a, hp); 1762 } else 1763 setproctitle("-%s", a); 1764 } 1765 1766 static void 1767 bump_nofile(void) 1768 { 1769 #define FD_CHUNK 32 1770 struct rlimit rl; 1771 1772 if (getrlimit(RLIMIT_NOFILE, &rl) < 0) { 1773 syslog(LOG_ERR, "getrlimit: %m"); 1774 return; 1775 } 1776 rl.rlim_cur = MIN(rl.rlim_max, rl.rlim_cur + FD_CHUNK); 1777 if (rl.rlim_cur <= rlim_ofile_cur) { 1778 syslog(LOG_ERR, 1779 "bump_nofile: cannot extend file limit, max = %d", 1780 (int)rl.rlim_cur); 1781 return; 1782 } 1783 1784 if (setrlimit(RLIMIT_NOFILE, &rl) < 0) { 1785 syslog(LOG_ERR, "setrlimit: %m"); 1786 return; 1787 } 1788 1789 rlim_ofile_cur = rl.rlim_cur; 1790 return; 1791 } 1792 1793 /* 1794 * Internet services provided internally by inetd: 1795 */ 1796 #define BUFSIZE 4096 1797 1798 /* ARGSUSED */ 1799 static void 1800 echo_stream(int s, struct servtab *sep) /* Echo service -- echo data back */ 1801 { 1802 char buffer[BUFSIZE]; 1803 ssize_t i; 1804 1805 inetd_setproctitle(sep->se_service, s); 1806 while ((i = read(s, buffer, sizeof(buffer))) > 0 && 1807 write(s, buffer, (size_t)i) > 0) 1808 ; 1809 } 1810 1811 /* ARGSUSED */ 1812 static void 1813 echo_dg(int s, struct servtab *sep) /* Echo service -- echo data back */ 1814 { 1815 char buffer[BUFSIZE]; 1816 ssize_t i; 1817 socklen_t size; 1818 struct sockaddr_storage ss; 1819 struct sockaddr *sa; 1820 1821 sa = (struct sockaddr *)(void *)&ss; 1822 size = sizeof(ss); 1823 if ((i = recvfrom(s, buffer, sizeof(buffer), 0, sa, &size)) < 0) 1824 return; 1825 if (port_good_dg(sa)) 1826 (void) sendto(s, buffer, (size_t)i, 0, sa, size); 1827 } 1828 1829 /* ARGSUSED */ 1830 static void 1831 discard_stream(int s, struct servtab *sep) /* Discard service -- ignore data */ 1832 { 1833 char buffer[BUFSIZE]; 1834 1835 inetd_setproctitle(sep->se_service, s); 1836 while ((errno = 0, read(s, buffer, sizeof(buffer)) > 0) || 1837 errno == EINTR) 1838 ; 1839 } 1840 1841 /* ARGSUSED */ 1842 static void 1843 discard_dg(int s, struct servtab *sep) /* Discard service -- ignore data */ 1844 1845 { 1846 char buffer[BUFSIZE]; 1847 1848 (void) read(s, buffer, sizeof(buffer)); 1849 } 1850 1851 #define LINESIZ 72 1852 char ring[128]; 1853 char *endring; 1854 1855 static void 1856 initring(void) 1857 { 1858 int i; 1859 1860 endring = ring; 1861 1862 for (i = 0; i <= 128; ++i) 1863 if (isprint(i)) 1864 *endring++ = i; 1865 } 1866 1867 /* ARGSUSED */ 1868 static void 1869 chargen_stream(int s,struct servtab *sep) /* Character generator */ 1870 { 1871 size_t len; 1872 char *rs, text[LINESIZ+2]; 1873 1874 inetd_setproctitle(sep->se_service, s); 1875 1876 if (!endring) { 1877 initring(); 1878 rs = ring; 1879 } 1880 1881 text[LINESIZ] = '\r'; 1882 text[LINESIZ + 1] = '\n'; 1883 for (rs = ring;;) { 1884 if ((len = endring - rs) >= LINESIZ) 1885 memmove(text, rs, LINESIZ); 1886 else { 1887 memmove(text, rs, len); 1888 memmove(text + len, ring, LINESIZ - len); 1889 } 1890 if (++rs == endring) 1891 rs = ring; 1892 if (write(s, text, sizeof(text)) != sizeof(text)) 1893 break; 1894 } 1895 } 1896 1897 /* ARGSUSED */ 1898 static void 1899 chargen_dg(int s, struct servtab *sep) /* Character generator */ 1900 { 1901 struct sockaddr_storage ss; 1902 struct sockaddr *sa; 1903 static char *rs; 1904 size_t len; 1905 socklen_t size; 1906 char text[LINESIZ+2]; 1907 1908 if (endring == 0) { 1909 initring(); 1910 rs = ring; 1911 } 1912 1913 sa = (struct sockaddr *)(void *)&ss; 1914 size = sizeof(ss); 1915 if (recvfrom(s, text, sizeof(text), 0, sa, &size) < 0) 1916 return; 1917 1918 if (!port_good_dg(sa)) 1919 return; 1920 1921 if ((len = endring - rs) >= LINESIZ) 1922 memmove(text, rs, LINESIZ); 1923 else { 1924 memmove(text, rs, len); 1925 memmove(text + len, ring, LINESIZ - len); 1926 } 1927 if (++rs == endring) 1928 rs = ring; 1929 text[LINESIZ] = '\r'; 1930 text[LINESIZ + 1] = '\n'; 1931 (void) sendto(s, text, sizeof(text), 0, sa, size); 1932 } 1933 1934 /* 1935 * Return a machine readable date and time, in the form of the 1936 * number of seconds since midnight, Jan 1, 1900. Since gettimeofday 1937 * returns the number of seconds since midnight, Jan 1, 1970, 1938 * we must add 2208988800 seconds to this figure to make up for 1939 * some seventy years Bell Labs was asleep. 1940 */ 1941 1942 static uint32_t 1943 machtime(void) 1944 { 1945 struct timeval tv; 1946 1947 if (gettimeofday(&tv, NULL) < 0) { 1948 if (debug) 1949 fprintf(stderr, "Unable to get time of day\n"); 1950 return (0); 1951 } 1952 #define OFFSET ((uint32_t)25567 * 24*60*60) 1953 return (htonl((uint32_t)(tv.tv_sec + OFFSET))); 1954 #undef OFFSET 1955 } 1956 1957 /* ARGSUSED */ 1958 static void 1959 machtime_stream(int s, struct servtab *sep) 1960 { 1961 uint32_t result; 1962 1963 result = machtime(); 1964 (void) write(s, &result, sizeof(result)); 1965 } 1966 1967 /* ARGSUSED */ 1968 void 1969 machtime_dg(int s, struct servtab *sep) 1970 { 1971 uint32_t result; 1972 struct sockaddr_storage ss; 1973 struct sockaddr *sa; 1974 socklen_t size; 1975 1976 sa = (struct sockaddr *)(void *)&ss; 1977 size = sizeof(ss); 1978 if (recvfrom(s, &result, sizeof(result), 0, sa, &size) < 0) 1979 return; 1980 if (!port_good_dg(sa)) 1981 return; 1982 result = machtime(); 1983 (void)sendto(s, &result, sizeof(result), 0, sa, size); 1984 } 1985 1986 /* ARGSUSED */ 1987 static void 1988 daytime_stream(int s,struct servtab *sep) 1989 /* Return human-readable time of day */ 1990 { 1991 char buffer[256]; 1992 time_t clk; 1993 int len; 1994 1995 clk = time((time_t *) 0); 1996 1997 len = snprintf(buffer, sizeof buffer, "%.24s\r\n", ctime(&clk)); 1998 (void) write(s, buffer, len); 1999 } 2000 2001 /* ARGSUSED */ 2002 void 2003 daytime_dg(int s, struct servtab *sep) 2004 /* Return human-readable time of day */ 2005 { 2006 char buffer[256]; 2007 time_t clk; 2008 struct sockaddr_storage ss; 2009 struct sockaddr *sa; 2010 socklen_t size; 2011 int len; 2012 2013 clk = time((time_t *) 0); 2014 2015 sa = (struct sockaddr *)(void *)&ss; 2016 size = sizeof(ss); 2017 if (recvfrom(s, buffer, sizeof(buffer), 0, sa, &size) < 0) 2018 return; 2019 if (!port_good_dg(sa)) 2020 return; 2021 len = snprintf(buffer, sizeof buffer, "%.24s\r\n", ctime(&clk)); 2022 (void) sendto(s, buffer, len, 0, sa, size); 2023 } 2024 2025 /* 2026 * print_service: 2027 * Dump relevant information to stderr 2028 */ 2029 static void 2030 print_service(const char *action, struct servtab *sep) 2031 { 2032 2033 if (isrpcservice(sep)) 2034 fprintf(stderr, 2035 "%s: %s rpcprog=%d, rpcvers = %d/%d, proto=%s, wait.max=%d.%d, user:group=%s:%s builtin=%lx server=%s" 2036 #ifdef IPSEC 2037 " policy=\"%s\"" 2038 #endif 2039 "\n", 2040 action, sep->se_service, 2041 sep->se_rpcprog, sep->se_rpcversh, sep->se_rpcversl, sep->se_proto, 2042 sep->se_wait, sep->se_max, sep->se_user, sep->se_group, 2043 (long)sep->se_bi, sep->se_server 2044 #ifdef IPSEC 2045 , (sep->se_policy ? sep->se_policy : "") 2046 #endif 2047 ); 2048 else 2049 fprintf(stderr, 2050 "%s: %s proto=%s%s, wait.max=%d.%d, user:group=%s:%s builtin=%lx server=%s" 2051 #ifdef IPSEC 2052 " policy=%s" 2053 #endif 2054 "\n", 2055 action, sep->se_service, 2056 sep->se_type == FAITH_TYPE ? "faith/" : "", 2057 sep->se_proto, 2058 sep->se_wait, sep->se_max, sep->se_user, sep->se_group, 2059 (long)sep->se_bi, sep->se_server 2060 #ifdef IPSEC 2061 , (sep->se_policy ? sep->se_policy : "") 2062 #endif 2063 ); 2064 } 2065 2066 static void 2067 usage(void) 2068 { 2069 #ifdef LIBWRAP 2070 (void)fprintf(stderr, "usage: %s [-dl] [conf]\n", getprogname()); 2071 #else 2072 (void)fprintf(stderr, "usage: %s [-d] [conf]\n", getprogname()); 2073 #endif 2074 exit(1); 2075 } 2076 2077 2078 /* 2079 * Based on TCPMUX.C by Mark K. Lottor November 1988 2080 * sri-nic::ps:<mkl>tcpmux.c 2081 */ 2082 2083 static int /* # of characters upto \r,\n or \0 */ 2084 get_line(int fd, char *buf, int len) 2085 { 2086 int count = 0; 2087 ssize_t n; 2088 2089 do { 2090 n = read(fd, buf, len-count); 2091 if (n == 0) 2092 return (count); 2093 if (n < 0) 2094 return (-1); 2095 while (--n >= 0) { 2096 if (*buf == '\r' || *buf == '\n' || *buf == '\0') 2097 return (count); 2098 count++; 2099 buf++; 2100 } 2101 } while (count < len); 2102 return (count); 2103 } 2104 2105 #define MAX_SERV_LEN (256+2) /* 2 bytes for \r\n */ 2106 2107 #define strwrite(fd, buf) (void) write(fd, buf, sizeof(buf)-1) 2108 2109 static void 2110 tcpmux(int ctrl, struct servtab *sep) 2111 { 2112 char service[MAX_SERV_LEN+1]; 2113 int len; 2114 2115 /* Get requested service name */ 2116 if ((len = get_line(ctrl, service, MAX_SERV_LEN)) < 0) { 2117 strwrite(ctrl, "-Error reading service name\r\n"); 2118 goto reject; 2119 } 2120 service[len] = '\0'; 2121 2122 if (debug) 2123 fprintf(stderr, "tcpmux: someone wants %s\n", service); 2124 2125 /* 2126 * Help is a required command, and lists available services, 2127 * one per line. 2128 */ 2129 if (!strcasecmp(service, "help")) { 2130 strwrite(ctrl, "+Available services:\r\n"); 2131 strwrite(ctrl, "help\r\n"); 2132 for (sep = servtab; sep != NULL; sep = sep->se_next) { 2133 if (!ISMUX(sep)) 2134 continue; 2135 (void)write(ctrl, sep->se_service, 2136 strlen(sep->se_service)); 2137 strwrite(ctrl, "\r\n"); 2138 } 2139 goto reject; 2140 } 2141 2142 /* Try matching a service in inetd.conf with the request */ 2143 for (sep = servtab; sep != NULL; sep = sep->se_next) { 2144 if (!ISMUX(sep)) 2145 continue; 2146 if (!strcasecmp(service, sep->se_service)) { 2147 if (ISMUXPLUS(sep)) 2148 strwrite(ctrl, "+Go\r\n"); 2149 run_service(ctrl, sep, 1 /* forked */); 2150 return; 2151 } 2152 } 2153 strwrite(ctrl, "-Service not available\r\n"); 2154 reject: 2155 _exit(1); 2156 } 2157 2158 /* 2159 * check if the address/port where send data to is one of the obvious ports 2160 * that are used for denial of service attacks like two echo ports 2161 * just echoing data between them 2162 */ 2163 static int 2164 port_good_dg(struct sockaddr *sa) 2165 { 2166 struct in_addr in; 2167 struct sockaddr_in *sin; 2168 #ifdef INET6 2169 struct in6_addr *in6; 2170 struct sockaddr_in6 *sin6; 2171 #endif 2172 u_int16_t port; 2173 int i; 2174 char hbuf[NI_MAXHOST]; 2175 2176 switch (sa->sa_family) { 2177 case AF_INET: 2178 sin = (struct sockaddr_in *)(void *)sa; 2179 in.s_addr = ntohl(sin->sin_addr.s_addr); 2180 port = ntohs(sin->sin_port); 2181 #ifdef INET6 2182 v4chk: 2183 #endif 2184 if (IN_MULTICAST(in.s_addr)) 2185 goto bad; 2186 switch ((in.s_addr & 0xff000000) >> 24) { 2187 case 0: case 127: case 255: 2188 goto bad; 2189 } 2190 if (dg_broadcast(&in)) 2191 goto bad; 2192 break; 2193 #ifdef INET6 2194 case AF_INET6: 2195 sin6 = (struct sockaddr_in6 *)(void *)sa; 2196 in6 = &sin6->sin6_addr; 2197 port = ntohs(sin6->sin6_port); 2198 if (IN6_IS_ADDR_MULTICAST(in6) || IN6_IS_ADDR_UNSPECIFIED(in6)) 2199 goto bad; 2200 if (IN6_IS_ADDR_V4MAPPED(in6) || IN6_IS_ADDR_V4COMPAT(in6)) { 2201 memcpy(&in, &in6->s6_addr[12], sizeof(in)); 2202 in.s_addr = ntohl(in.s_addr); 2203 goto v4chk; 2204 } 2205 break; 2206 #endif 2207 default: 2208 /* XXX unsupported af, is it safe to assume it to be safe? */ 2209 return (1); 2210 } 2211 2212 for (i = 0; bad_ports[i] != 0; i++) { 2213 if (port == bad_ports[i]) 2214 goto bad; 2215 } 2216 2217 return (1); 2218 2219 bad: 2220 if (getnameinfo(sa, sa->sa_len, hbuf, (socklen_t)sizeof(hbuf), NULL, 0, 2221 niflags) != 0) 2222 strlcpy(hbuf, "?", sizeof(hbuf)); 2223 syslog(LOG_WARNING,"Possible DoS attack from %s, Port %d", 2224 hbuf, port); 2225 return (0); 2226 } 2227 2228 /* XXX need optimization */ 2229 static int 2230 dg_broadcast(struct in_addr *in) 2231 { 2232 struct ifaddrs *ifa, *ifap; 2233 struct sockaddr_in *sin; 2234 2235 if (getifaddrs(&ifap) < 0) 2236 return (0); 2237 for (ifa = ifap; ifa; ifa = ifa->ifa_next) { 2238 if (ifa->ifa_addr->sa_family != AF_INET || 2239 (ifa->ifa_flags & IFF_BROADCAST) == 0) 2240 continue; 2241 sin = (struct sockaddr_in *)(void *)ifa->ifa_broadaddr; 2242 if (sin->sin_addr.s_addr == in->s_addr) { 2243 freeifaddrs(ifap); 2244 return (1); 2245 } 2246 } 2247 freeifaddrs(ifap); 2248 return (0); 2249 } 2250 2251 static int 2252 my_kevent(const struct kevent *changelist, size_t nchanges, 2253 struct kevent *eventlist, size_t nevents) 2254 { 2255 int result; 2256 2257 while ((result = kevent(kq, changelist, nchanges, eventlist, nevents, 2258 NULL)) < 0) 2259 if (errno != EINTR) { 2260 syslog(LOG_ERR, "kevent: %m"); 2261 exit(EXIT_FAILURE); 2262 } 2263 2264 return (result); 2265 } 2266 2267 static struct kevent * 2268 allocchange(void) 2269 { 2270 if (changes == A_CNT(changebuf)) { 2271 (void) my_kevent(changebuf, A_CNT(changebuf), NULL, 0); 2272 changes = 0; 2273 } 2274 2275 return (&changebuf[changes++]); 2276 } 2277