1 /* $NetBSD: inetd.c,v 1.126 2019/12/27 09:22:20 msaitoh 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 1.126 2019/12/27 09:22:20 msaitoh 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 MAXARGV (64) 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 MAXARGV (64) 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 64 302 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 %u", 766 sep->se_server, WEXITSTATUS(status)); 767 else if (WIFSIGNALED(status)) 768 syslog(LOG_WARNING, 769 "%s: exit signal %u", 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 strlcpy(sep->se_ctrladdr_un.sun_path, 853 sep->se_service, n + 1); 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 /* Avoid setting a policy if a policy specifier doesn't exist. */ 1092 if (sep->se_policy != NULL) { 1093 int e = ipsecsetup(sep->se_family, sep->se_fd, sep->se_policy); 1094 if (e < 0) { 1095 syslog(LOG_ERR, "%s/%s: ipsec setup failed", 1096 sep->se_service, sep->se_proto); 1097 (void)close(sep->se_fd); 1098 sep->se_fd = -1; 1099 return; 1100 } 1101 } 1102 #endif 1103 1104 if (bind(sep->se_fd, &sep->se_ctrladdr, 1105 (socklen_t)sep->se_ctrladdr_size) < 0) { 1106 if (debug) 1107 fprintf(stderr, "bind failed on %s/%s: %s\n", 1108 sep->se_service, sep->se_proto, strerror(errno)); 1109 syslog(LOG_ERR, "%s/%s: bind: %m", 1110 sep->se_service, sep->se_proto); 1111 (void) close(sep->se_fd); 1112 sep->se_fd = -1; 1113 if (!timingout) { 1114 timingout = 1; 1115 alarm(RETRYTIME); 1116 } 1117 return; 1118 } 1119 if (sep->se_socktype == SOCK_STREAM) 1120 listen(sep->se_fd, 10); 1121 1122 /* Set the accept filter, if specified. To be done after listen.*/ 1123 if (sep->se_accf.af_name[0] != 0 && setsockopt(sep->se_fd, SOL_SOCKET, 1124 SO_ACCEPTFILTER, &sep->se_accf, 1125 (socklen_t)sizeof(sep->se_accf)) < 0) 1126 syslog(LOG_ERR, "setsockopt(SO_ACCEPTFILTER %s): %m", 1127 sep->se_accf.af_name); 1128 1129 ev = allocchange(); 1130 EV_SET(ev, sep->se_fd, EVFILT_READ, EV_ADD | EV_ENABLE, 0, 0, 1131 (intptr_t)sep); 1132 if (sep->se_fd > maxsock) { 1133 maxsock = sep->se_fd; 1134 if (maxsock > (int)(rlim_ofile_cur - FD_MARGIN)) 1135 bump_nofile(); 1136 } 1137 if (debug) 1138 fprintf(stderr, "registered %s on %d\n", 1139 sep->se_server, sep->se_fd); 1140 } 1141 1142 /* 1143 * Finish with a service and its socket. 1144 */ 1145 static void 1146 close_sep(struct servtab *sep) 1147 { 1148 if (sep->se_fd >= 0) { 1149 (void) close(sep->se_fd); 1150 sep->se_fd = -1; 1151 } 1152 sep->se_count = 0; 1153 } 1154 1155 static void 1156 register_rpc(struct servtab *sep) 1157 { 1158 #ifdef RPC 1159 struct netbuf nbuf; 1160 struct sockaddr_storage ss; 1161 struct netconfig *nconf; 1162 socklen_t socklen; 1163 int n; 1164 1165 if ((nconf = getnetconfigent(sep->se_proto+4)) == NULL) { 1166 syslog(LOG_ERR, "%s: getnetconfigent failed", 1167 sep->se_proto); 1168 return; 1169 } 1170 socklen = sizeof ss; 1171 if (getsockname(sep->se_fd, (struct sockaddr *)(void *)&ss, &socklen) < 0) { 1172 syslog(LOG_ERR, "%s/%s: getsockname: %m", 1173 sep->se_service, sep->se_proto); 1174 return; 1175 } 1176 1177 nbuf.buf = &ss; 1178 nbuf.len = ss.ss_len; 1179 nbuf.maxlen = sizeof (struct sockaddr_storage); 1180 for (n = sep->se_rpcversl; n <= sep->se_rpcversh; n++) { 1181 if (debug) 1182 fprintf(stderr, "rpcb_set: %u %d %s %s\n", 1183 sep->se_rpcprog, n, nconf->nc_netid, 1184 taddr2uaddr(nconf, &nbuf)); 1185 (void)rpcb_unset((unsigned int)sep->se_rpcprog, (unsigned int)n, nconf); 1186 if (!rpcb_set((unsigned int)sep->se_rpcprog, (unsigned int)n, nconf, &nbuf)) 1187 syslog(LOG_ERR, "rpcb_set: %u %d %s %s%s", 1188 sep->se_rpcprog, n, nconf->nc_netid, 1189 taddr2uaddr(nconf, &nbuf), clnt_spcreateerror("")); 1190 } 1191 #endif /* RPC */ 1192 } 1193 1194 static void 1195 unregister_rpc(struct servtab *sep) 1196 { 1197 #ifdef RPC 1198 int n; 1199 struct netconfig *nconf; 1200 1201 if ((nconf = getnetconfigent(sep->se_proto+4)) == NULL) { 1202 syslog(LOG_ERR, "%s: getnetconfigent failed", 1203 sep->se_proto); 1204 return; 1205 } 1206 1207 for (n = sep->se_rpcversl; n <= sep->se_rpcversh; n++) { 1208 if (debug) 1209 fprintf(stderr, "rpcb_unset(%u, %d, %s)\n", 1210 sep->se_rpcprog, n, nconf->nc_netid); 1211 if (!rpcb_unset((unsigned int)sep->se_rpcprog, (unsigned int)n, nconf)) 1212 syslog(LOG_ERR, "rpcb_unset(%u, %d, %s) failed\n", 1213 sep->se_rpcprog, n, nconf->nc_netid); 1214 } 1215 #endif /* RPC */ 1216 } 1217 1218 1219 static struct servtab * 1220 enter(struct servtab *cp) 1221 { 1222 struct servtab *sep; 1223 1224 sep = malloc(sizeof (*sep)); 1225 if (sep == NULL) { 1226 syslog(LOG_ERR, "Out of memory."); 1227 exit(1); 1228 } 1229 *sep = *cp; 1230 sep->se_fd = -1; 1231 sep->se_rpcprog = -1; 1232 sep->se_next = servtab; 1233 servtab = sep; 1234 return (sep); 1235 } 1236 1237 FILE *fconfig = NULL; 1238 struct servtab serv; 1239 char line[LINE_MAX]; 1240 char *defhost; 1241 #ifdef IPSEC 1242 static char *policy = NULL; 1243 #endif 1244 1245 static int 1246 setconfig(void) 1247 { 1248 if (defhost) 1249 free(defhost); 1250 defhost = newstr("*"); 1251 #ifdef IPSEC 1252 if (policy) 1253 free(policy); 1254 policy = NULL; 1255 #endif 1256 if (fconfig != NULL) { 1257 fseek(fconfig, 0L, SEEK_SET); 1258 return (1); 1259 } 1260 fconfig = fopen(CONFIG, "r"); 1261 return (fconfig != NULL); 1262 } 1263 1264 static void 1265 endconfig(void) 1266 { 1267 if (fconfig != NULL) { 1268 (void) fclose(fconfig); 1269 fconfig = NULL; 1270 } 1271 if (defhost != NULL) { 1272 free(defhost); 1273 defhost = NULL; 1274 } 1275 } 1276 1277 static struct servtab * 1278 getconfigent(void) 1279 { 1280 struct servtab *sep = &serv; 1281 int argc, val; 1282 char *cp, *cp0, *arg, *buf0, *buf1, *sz0, *sz1; 1283 static char TCPMUX_TOKEN[] = "tcpmux/"; 1284 #define MUX_LEN (sizeof(TCPMUX_TOKEN)-1) 1285 char *hostdelim; 1286 1287 more: 1288 while ((cp = nextline(fconfig)) != NULL) { 1289 #ifdef IPSEC 1290 /* lines starting with #@ is not a comment, but the policy */ 1291 if (cp[0] == '#' && cp[1] == '@') { 1292 char *p; 1293 for (p = cp + 2; p && *p && isspace((unsigned char)*p); p++) 1294 ; 1295 if (*p == '\0') { 1296 if (policy) 1297 free(policy); 1298 policy = NULL; 1299 } else { 1300 if (ipsecsetup_test(p) < 0) { 1301 syslog(LOG_ERR, 1302 "%s: invalid ipsec policy \"%s\"", 1303 CONFIG, p); 1304 exit(1); 1305 } else { 1306 if (policy) 1307 free(policy); 1308 policy = newstr(p); 1309 } 1310 } 1311 } 1312 #endif 1313 if (*cp == '#' || *cp == '\0') 1314 continue; 1315 break; 1316 } 1317 if (cp == NULL) 1318 return (NULL); 1319 /* 1320 * clear the static buffer, since some fields (se_ctrladdr, 1321 * for example) don't get initialized here. 1322 */ 1323 memset(sep, 0, sizeof *sep); 1324 arg = skip(&cp); 1325 if (cp == NULL) { 1326 /* got an empty line containing just blanks/tabs. */ 1327 goto more; 1328 } 1329 /* Check for a host name. */ 1330 hostdelim = strrchr(arg, ':'); 1331 if (hostdelim) { 1332 *hostdelim = '\0'; 1333 if (arg[0] == '[' && hostdelim > arg && hostdelim[-1] == ']') { 1334 hostdelim[-1] = '\0'; 1335 sep->se_hostaddr = newstr(arg + 1); 1336 } else 1337 sep->se_hostaddr = newstr(arg); 1338 arg = hostdelim + 1; 1339 /* 1340 * If the line is of the form `host:', then just change the 1341 * default host for the following lines. 1342 */ 1343 if (*arg == '\0') { 1344 arg = skip(&cp); 1345 if (cp == NULL) { 1346 free(defhost); 1347 defhost = sep->se_hostaddr; 1348 goto more; 1349 } 1350 } 1351 } else 1352 sep->se_hostaddr = newstr(defhost); 1353 if (strncmp(arg, TCPMUX_TOKEN, MUX_LEN) == 0) { 1354 char *c = arg + MUX_LEN; 1355 if (*c == '+') { 1356 sep->se_type = MUXPLUS_TYPE; 1357 c++; 1358 } else 1359 sep->se_type = MUX_TYPE; 1360 sep->se_service = newstr(c); 1361 } else { 1362 sep->se_service = newstr(arg); 1363 sep->se_type = NORM_TYPE; 1364 } 1365 1366 arg = sskip(&cp); 1367 if (strncmp(arg, "stream", sizeof("stream") - 1) == 0) { 1368 char *accf, *accf_arg; 1369 1370 sep->se_socktype = SOCK_STREAM; 1371 1372 /* one and only one accept filter */ 1373 accf = strchr(arg, ':'); 1374 if (accf) { 1375 if (accf != strrchr(arg, ':') ||/* more than one */ 1376 *(accf + 1) == '\0') { /* nothing beyond */ 1377 sep->se_socktype = -1; 1378 } else { 1379 accf++; /* skip delimiter */ 1380 strlcpy(sep->se_accf.af_name, accf, 1381 sizeof(sep->se_accf.af_name)); 1382 accf_arg = strchr(accf, ','); 1383 if (accf_arg) { /* zero or one arg, no more */ 1384 if (strrchr(accf, ',') != accf_arg) { 1385 sep->se_socktype = -1; 1386 } else { 1387 accf_arg++; 1388 strlcpy(sep->se_accf.af_arg, 1389 accf_arg, 1390 sizeof(sep->se_accf.af_arg)); 1391 } 1392 } 1393 } 1394 } 1395 } 1396 1397 else if (strcmp(arg, "dgram") == 0) 1398 sep->se_socktype = SOCK_DGRAM; 1399 else if (strcmp(arg, "rdm") == 0) 1400 sep->se_socktype = SOCK_RDM; 1401 else if (strcmp(arg, "seqpacket") == 0) 1402 sep->se_socktype = SOCK_SEQPACKET; 1403 else if (strcmp(arg, "raw") == 0) 1404 sep->se_socktype = SOCK_RAW; 1405 else 1406 sep->se_socktype = -1; 1407 1408 arg = sskip(&cp); 1409 if (sep->se_type == NORM_TYPE && 1410 strncmp(arg, "faith/", strlen("faith/")) == 0) { 1411 arg += strlen("faith/"); 1412 sep->se_type = FAITH_TYPE; 1413 } 1414 sep->se_proto = newstr(arg); 1415 1416 #define MALFORMED(arg) \ 1417 do { \ 1418 syslog(LOG_ERR, "%s: malformed buffer size option `%s'", \ 1419 sep->se_service, (arg)); \ 1420 goto more; \ 1421 /*NOTREACHED*/ \ 1422 } while (/*CONSTCOND*/0) 1423 1424 #define GETVAL(arg) \ 1425 do { \ 1426 if (!isdigit((unsigned char)*(arg))) \ 1427 MALFORMED(arg); \ 1428 val = (int)strtol((arg), &cp0, 10); \ 1429 if (cp0 != NULL) { \ 1430 if (cp0[1] != '\0') \ 1431 MALFORMED((arg)); \ 1432 if (cp0[0] == 'k') \ 1433 val *= 1024; \ 1434 if (cp0[0] == 'm') \ 1435 val *= 1024 * 1024; \ 1436 } \ 1437 if (val < 1) { \ 1438 syslog(LOG_ERR, "%s: invalid buffer size `%s'", \ 1439 sep->se_service, (arg)); \ 1440 goto more; \ 1441 } \ 1442 /*NOTREACHED*/ \ 1443 } while (/*CONSTCOND*/0) 1444 1445 #define ASSIGN(arg) \ 1446 do { \ 1447 if (strcmp((arg), "sndbuf") == 0) \ 1448 sep->se_sndbuf = val; \ 1449 else if (strcmp((arg), "rcvbuf") == 0) \ 1450 sep->se_rcvbuf = val; \ 1451 else \ 1452 MALFORMED((arg)); \ 1453 } while (/*CONSTCOND*/0) 1454 1455 /* 1456 * Extract the send and receive buffer sizes before parsing 1457 * the protocol. 1458 */ 1459 sep->se_sndbuf = sep->se_rcvbuf = 0; 1460 buf0 = buf1 = sz0 = sz1 = NULL; 1461 if ((buf0 = strchr(sep->se_proto, ',')) != NULL) { 1462 /* Not meaningful for Tcpmux services. */ 1463 if (ISMUX(sep)) { 1464 syslog(LOG_ERR, "%s: can't specify buffer sizes for " 1465 "tcpmux services", sep->se_service); 1466 goto more; 1467 } 1468 1469 /* Skip the , */ 1470 *buf0++ = '\0'; 1471 1472 /* Check to see if another socket buffer size was specified. */ 1473 if ((buf1 = strchr(buf0, ',')) != NULL) { 1474 /* Skip the , */ 1475 *buf1++ = '\0'; 1476 1477 /* Make sure a 3rd one wasn't specified. */ 1478 if (strchr(buf1, ',') != NULL) { 1479 syslog(LOG_ERR, "%s: too many buffer sizes", 1480 sep->se_service); 1481 goto more; 1482 } 1483 1484 /* Locate the size. */ 1485 if ((sz1 = strchr(buf1, '=')) == NULL) 1486 MALFORMED(buf1); 1487 1488 /* Skip the = */ 1489 *sz1++ = '\0'; 1490 } 1491 1492 /* Locate the size. */ 1493 if ((sz0 = strchr(buf0, '=')) == NULL) 1494 MALFORMED(buf0); 1495 1496 /* Skip the = */ 1497 *sz0++ = '\0'; 1498 1499 GETVAL(sz0); 1500 ASSIGN(buf0); 1501 1502 if (buf1 != NULL) { 1503 GETVAL(sz1); 1504 ASSIGN(buf1); 1505 } 1506 } 1507 1508 #undef ASSIGN 1509 #undef GETVAL 1510 #undef MALFORMED 1511 1512 if (strcmp(sep->se_proto, "unix") == 0) { 1513 sep->se_family = AF_LOCAL; 1514 } else { 1515 val = (int)strlen(sep->se_proto); 1516 if (!val) { 1517 syslog(LOG_ERR, "%s: invalid protocol specified", 1518 sep->se_service); 1519 goto more; 1520 } 1521 val = sep->se_proto[val - 1]; 1522 switch (val) { 1523 case '4': /*tcp4 or udp4*/ 1524 sep->se_family = AF_INET; 1525 break; 1526 #ifdef INET6 1527 case '6': /*tcp6 or udp6*/ 1528 sep->se_family = AF_INET6; 1529 break; 1530 #endif 1531 default: 1532 sep->se_family = AF_INET; /*will become AF_INET6*/ 1533 break; 1534 } 1535 if (strncmp(sep->se_proto, "rpc/", 4) == 0) { 1536 #ifdef RPC 1537 char *cp1, *ccp; 1538 cp1 = strchr(sep->se_service, '/'); 1539 if (cp1 == 0) { 1540 syslog(LOG_ERR, "%s: no rpc version", 1541 sep->se_service); 1542 goto more; 1543 } 1544 *cp1++ = '\0'; 1545 sep->se_rpcversl = sep->se_rpcversh = 1546 (int)strtol(cp1, &ccp, 0); 1547 if (ccp == cp1) { 1548 badafterall: 1549 syslog(LOG_ERR, "%s/%s: bad rpc version", 1550 sep->se_service, cp1); 1551 goto more; 1552 } 1553 if (*ccp == '-') { 1554 cp1 = ccp + 1; 1555 sep->se_rpcversh = (int)strtol(cp1, &ccp, 0); 1556 if (ccp == cp1) 1557 goto badafterall; 1558 } 1559 #else 1560 syslog(LOG_ERR, "%s: rpc services not supported", 1561 sep->se_service); 1562 goto more; 1563 #endif /* RPC */ 1564 } 1565 } 1566 arg = sskip(&cp); 1567 { 1568 char *cp1; 1569 if ((cp1 = strchr(arg, ':')) == NULL) 1570 cp1 = strchr(arg, '.'); 1571 if (cp1 != NULL) { 1572 *cp1++ = '\0'; 1573 sep->se_max = atoi(cp1); 1574 } else 1575 sep->se_max = TOOMANY; 1576 } 1577 sep->se_wait = strcmp(arg, "wait") == 0; 1578 if (ISMUX(sep)) { 1579 /* 1580 * Silently enforce "nowait" for TCPMUX services since 1581 * they don't have an assigned port to listen on. 1582 */ 1583 sep->se_wait = 0; 1584 1585 if (strncmp(sep->se_proto, "tcp", 3)) { 1586 syslog(LOG_ERR, 1587 "%s: bad protocol for tcpmux service %s", 1588 CONFIG, sep->se_service); 1589 goto more; 1590 } 1591 if (sep->se_socktype != SOCK_STREAM) { 1592 syslog(LOG_ERR, 1593 "%s: bad socket type for tcpmux service %s", 1594 CONFIG, sep->se_service); 1595 goto more; 1596 } 1597 } 1598 sep->se_user = newstr(sskip(&cp)); 1599 if ((sep->se_group = strchr(sep->se_user, ':')) != NULL) 1600 *sep->se_group++ = '\0'; 1601 else if ((sep->se_group = strchr(sep->se_user, '.')) != NULL) 1602 *sep->se_group++ = '\0'; 1603 1604 sep->se_server = newstr(sskip(&cp)); 1605 if (strcmp(sep->se_server, "internal") == 0) { 1606 struct biltin *bi; 1607 1608 for (bi = biltins; bi->bi_service; bi++) 1609 if (bi->bi_socktype == sep->se_socktype && 1610 strcmp(bi->bi_service, sep->se_service) == 0) 1611 break; 1612 if (bi->bi_service == 0) { 1613 syslog(LOG_ERR, "internal service %s unknown", 1614 sep->se_service); 1615 goto more; 1616 } 1617 sep->se_bi = bi; 1618 sep->se_wait = bi->bi_wait; 1619 } else 1620 sep->se_bi = NULL; 1621 argc = 0; 1622 for (arg = skip(&cp); cp; arg = skip(&cp)) { 1623 if (argc < MAXARGV) 1624 sep->se_argv[argc++] = newstr(arg); 1625 } 1626 while (argc <= MAXARGV) 1627 sep->se_argv[argc++] = NULL; 1628 #ifdef IPSEC 1629 sep->se_policy = policy ? newstr(policy) : NULL; 1630 #endif 1631 return (sep); 1632 } 1633 1634 static void 1635 freeconfig(struct servtab *cp) 1636 { 1637 int i; 1638 1639 if (cp->se_hostaddr) 1640 free(cp->se_hostaddr); 1641 if (cp->se_service) 1642 free(cp->se_service); 1643 if (cp->se_proto) 1644 free(cp->se_proto); 1645 if (cp->se_user) 1646 free(cp->se_user); 1647 /* Note: se_group is part of the newstr'ed se_user */ 1648 if (cp->se_server) 1649 free(cp->se_server); 1650 for (i = 0; i < MAXARGV; i++) 1651 if (cp->se_argv[i]) 1652 free(cp->se_argv[i]); 1653 #ifdef IPSEC 1654 if (cp->se_policy) 1655 free(cp->se_policy); 1656 #endif 1657 } 1658 1659 1660 /* 1661 * Safe skip - if skip returns null, log a syntax error in the 1662 * configuration file and exit. 1663 */ 1664 static char * 1665 sskip(char **cpp) 1666 { 1667 char *cp; 1668 1669 cp = skip(cpp); 1670 if (cp == NULL) { 1671 syslog(LOG_ERR, "%s: syntax error", CONFIG); 1672 exit(1); 1673 } 1674 return (cp); 1675 } 1676 1677 static char * 1678 skip(char **cpp) 1679 { 1680 char *cp = *cpp; 1681 char *start; 1682 char quote; 1683 1684 if (*cpp == NULL) 1685 return (NULL); 1686 1687 again: 1688 while (*cp == ' ' || *cp == '\t') 1689 cp++; 1690 if (*cp == '\0') { 1691 int c; 1692 1693 c = getc(fconfig); 1694 (void) ungetc(c, fconfig); 1695 if (c == ' ' || c == '\t') 1696 if ((cp = nextline(fconfig)) != NULL) 1697 goto again; 1698 *cpp = NULL; 1699 return (NULL); 1700 } 1701 start = cp; 1702 quote = '\0'; 1703 while (*cp && (quote || (*cp != ' ' && *cp != '\t'))) { 1704 if (*cp == '\'' || *cp == '"') { 1705 if (quote && *cp != quote) 1706 cp++; 1707 else { 1708 if (quote) 1709 quote = '\0'; 1710 else 1711 quote = *cp; 1712 memmove(cp, cp+1, strlen(cp)); 1713 } 1714 } else 1715 cp++; 1716 } 1717 if (*cp != '\0') 1718 *cp++ = '\0'; 1719 *cpp = cp; 1720 return (start); 1721 } 1722 1723 static char * 1724 nextline(FILE *fd) 1725 { 1726 char *cp; 1727 1728 if (fgets(line, (int)sizeof(line), fd) == NULL) 1729 return (NULL); 1730 cp = strchr(line, '\n'); 1731 if (cp) 1732 *cp = '\0'; 1733 return (line); 1734 } 1735 1736 static char * 1737 newstr(const char *cp) 1738 { 1739 char *dp; 1740 if ((dp = strdup((cp != NULL) ? cp : "")) != NULL) 1741 return (dp); 1742 syslog(LOG_ERR, "strdup: %m"); 1743 exit(1); 1744 /*NOTREACHED*/ 1745 } 1746 1747 static void 1748 inetd_setproctitle(char *a, int s) 1749 { 1750 socklen_t size; 1751 struct sockaddr_storage ss; 1752 char hbuf[NI_MAXHOST]; 1753 const char *hp; 1754 struct sockaddr *sa; 1755 1756 size = sizeof(ss); 1757 sa = (struct sockaddr *)(void *)&ss; 1758 if (getpeername(s, sa, &size) == 0) { 1759 if (getnameinfo(sa, size, hbuf, (socklen_t)sizeof(hbuf), NULL, 1760 0, niflags) != 0) 1761 hp = "?"; 1762 else 1763 hp = hbuf; 1764 setproctitle("-%s [%s]", a, hp); 1765 } else 1766 setproctitle("-%s", a); 1767 } 1768 1769 static void 1770 bump_nofile(void) 1771 { 1772 #define FD_CHUNK 32 1773 struct rlimit rl; 1774 1775 if (getrlimit(RLIMIT_NOFILE, &rl) < 0) { 1776 syslog(LOG_ERR, "getrlimit: %m"); 1777 return; 1778 } 1779 rl.rlim_cur = MIN(rl.rlim_max, rl.rlim_cur + FD_CHUNK); 1780 if (rl.rlim_cur <= rlim_ofile_cur) { 1781 syslog(LOG_ERR, 1782 "bump_nofile: cannot extend file limit, max = %d", 1783 (int)rl.rlim_cur); 1784 return; 1785 } 1786 1787 if (setrlimit(RLIMIT_NOFILE, &rl) < 0) { 1788 syslog(LOG_ERR, "setrlimit: %m"); 1789 return; 1790 } 1791 1792 rlim_ofile_cur = rl.rlim_cur; 1793 return; 1794 } 1795 1796 /* 1797 * Internet services provided internally by inetd: 1798 */ 1799 #define BUFSIZE 4096 1800 1801 /* ARGSUSED */ 1802 static void 1803 echo_stream(int s, struct servtab *sep) /* Echo service -- echo data back */ 1804 { 1805 char buffer[BUFSIZE]; 1806 ssize_t i; 1807 1808 inetd_setproctitle(sep->se_service, s); 1809 while ((i = read(s, buffer, sizeof(buffer))) > 0 && 1810 write(s, buffer, (size_t)i) > 0) 1811 ; 1812 } 1813 1814 /* ARGSUSED */ 1815 static void 1816 echo_dg(int s, struct servtab *sep) /* Echo service -- echo data back */ 1817 { 1818 char buffer[BUFSIZE]; 1819 ssize_t i; 1820 socklen_t size; 1821 struct sockaddr_storage ss; 1822 struct sockaddr *sa; 1823 1824 sa = (struct sockaddr *)(void *)&ss; 1825 size = sizeof(ss); 1826 if ((i = recvfrom(s, buffer, sizeof(buffer), 0, sa, &size)) < 0) 1827 return; 1828 if (port_good_dg(sa)) 1829 (void) sendto(s, buffer, (size_t)i, 0, sa, size); 1830 } 1831 1832 /* ARGSUSED */ 1833 static void 1834 discard_stream(int s, struct servtab *sep) /* Discard service -- ignore data */ 1835 { 1836 char buffer[BUFSIZE]; 1837 1838 inetd_setproctitle(sep->se_service, s); 1839 while ((errno = 0, read(s, buffer, sizeof(buffer)) > 0) || 1840 errno == EINTR) 1841 ; 1842 } 1843 1844 /* ARGSUSED */ 1845 static void 1846 discard_dg(int s, struct servtab *sep) /* Discard service -- ignore data */ 1847 1848 { 1849 char buffer[BUFSIZE]; 1850 1851 (void) read(s, buffer, sizeof(buffer)); 1852 } 1853 1854 #define LINESIZ 72 1855 char ring[128]; 1856 char *endring; 1857 1858 static void 1859 initring(void) 1860 { 1861 int i; 1862 1863 endring = ring; 1864 1865 for (i = 0; i <= 128; ++i) 1866 if (isprint(i)) 1867 *endring++ = i; 1868 } 1869 1870 /* ARGSUSED */ 1871 static void 1872 chargen_stream(int s,struct servtab *sep) /* Character generator */ 1873 { 1874 size_t len; 1875 char *rs, text[LINESIZ+2]; 1876 1877 inetd_setproctitle(sep->se_service, s); 1878 1879 if (!endring) { 1880 initring(); 1881 rs = ring; 1882 } 1883 1884 text[LINESIZ] = '\r'; 1885 text[LINESIZ + 1] = '\n'; 1886 for (rs = ring;;) { 1887 if ((len = endring - rs) >= LINESIZ) 1888 memmove(text, rs, LINESIZ); 1889 else { 1890 memmove(text, rs, len); 1891 memmove(text + len, ring, LINESIZ - len); 1892 } 1893 if (++rs == endring) 1894 rs = ring; 1895 if (write(s, text, sizeof(text)) != sizeof(text)) 1896 break; 1897 } 1898 } 1899 1900 /* ARGSUSED */ 1901 static void 1902 chargen_dg(int s, struct servtab *sep) /* Character generator */ 1903 { 1904 struct sockaddr_storage ss; 1905 struct sockaddr *sa; 1906 static char *rs; 1907 size_t len; 1908 socklen_t size; 1909 char text[LINESIZ+2]; 1910 1911 if (endring == 0) { 1912 initring(); 1913 rs = ring; 1914 } 1915 1916 sa = (struct sockaddr *)(void *)&ss; 1917 size = sizeof(ss); 1918 if (recvfrom(s, text, sizeof(text), 0, sa, &size) < 0) 1919 return; 1920 1921 if (!port_good_dg(sa)) 1922 return; 1923 1924 if ((len = endring - rs) >= LINESIZ) 1925 memmove(text, rs, LINESIZ); 1926 else { 1927 memmove(text, rs, len); 1928 memmove(text + len, ring, LINESIZ - len); 1929 } 1930 if (++rs == endring) 1931 rs = ring; 1932 text[LINESIZ] = '\r'; 1933 text[LINESIZ + 1] = '\n'; 1934 (void) sendto(s, text, sizeof(text), 0, sa, size); 1935 } 1936 1937 /* 1938 * Return a machine readable date and time, in the form of the 1939 * number of seconds since midnight, Jan 1, 1900. Since gettimeofday 1940 * returns the number of seconds since midnight, Jan 1, 1970, 1941 * we must add 2208988800 seconds to this figure to make up for 1942 * some seventy years Bell Labs was asleep. 1943 */ 1944 1945 static uint32_t 1946 machtime(void) 1947 { 1948 struct timeval tv; 1949 1950 if (gettimeofday(&tv, NULL) < 0) { 1951 if (debug) 1952 fprintf(stderr, "Unable to get time of day\n"); 1953 return (0); 1954 } 1955 #define OFFSET ((uint32_t)25567 * 24*60*60) 1956 return (htonl((uint32_t)(tv.tv_sec + OFFSET))); 1957 #undef OFFSET 1958 } 1959 1960 /* ARGSUSED */ 1961 static void 1962 machtime_stream(int s, struct servtab *sep) 1963 { 1964 uint32_t result; 1965 1966 result = machtime(); 1967 (void) write(s, &result, sizeof(result)); 1968 } 1969 1970 /* ARGSUSED */ 1971 void 1972 machtime_dg(int s, struct servtab *sep) 1973 { 1974 uint32_t result; 1975 struct sockaddr_storage ss; 1976 struct sockaddr *sa; 1977 socklen_t size; 1978 1979 sa = (struct sockaddr *)(void *)&ss; 1980 size = sizeof(ss); 1981 if (recvfrom(s, &result, sizeof(result), 0, sa, &size) < 0) 1982 return; 1983 if (!port_good_dg(sa)) 1984 return; 1985 result = machtime(); 1986 (void)sendto(s, &result, sizeof(result), 0, sa, size); 1987 } 1988 1989 /* ARGSUSED */ 1990 static void 1991 daytime_stream(int s,struct servtab *sep) 1992 /* Return human-readable time of day */ 1993 { 1994 char buffer[256]; 1995 time_t clk; 1996 int len; 1997 1998 clk = time((time_t *) 0); 1999 2000 len = snprintf(buffer, sizeof buffer, "%.24s\r\n", ctime(&clk)); 2001 (void) write(s, buffer, len); 2002 } 2003 2004 /* ARGSUSED */ 2005 void 2006 daytime_dg(int s, struct servtab *sep) 2007 /* Return human-readable time of day */ 2008 { 2009 char buffer[256]; 2010 time_t clk; 2011 struct sockaddr_storage ss; 2012 struct sockaddr *sa; 2013 socklen_t size; 2014 int len; 2015 2016 clk = time((time_t *) 0); 2017 2018 sa = (struct sockaddr *)(void *)&ss; 2019 size = sizeof(ss); 2020 if (recvfrom(s, buffer, sizeof(buffer), 0, sa, &size) < 0) 2021 return; 2022 if (!port_good_dg(sa)) 2023 return; 2024 len = snprintf(buffer, sizeof buffer, "%.24s\r\n", ctime(&clk)); 2025 (void) sendto(s, buffer, len, 0, sa, size); 2026 } 2027 2028 /* 2029 * print_service: 2030 * Dump relevant information to stderr 2031 */ 2032 static void 2033 print_service(const char *action, struct servtab *sep) 2034 { 2035 2036 if (isrpcservice(sep)) 2037 fprintf(stderr, 2038 "%s: %s rpcprog=%d, rpcvers = %d/%d, proto=%s, wait.max=%d.%d, user:group=%s:%s builtin=%lx server=%s" 2039 #ifdef IPSEC 2040 " policy=\"%s\"" 2041 #endif 2042 "\n", 2043 action, sep->se_service, 2044 sep->se_rpcprog, sep->se_rpcversh, sep->se_rpcversl, sep->se_proto, 2045 sep->se_wait, sep->se_max, sep->se_user, sep->se_group, 2046 (long)sep->se_bi, sep->se_server 2047 #ifdef IPSEC 2048 , (sep->se_policy ? sep->se_policy : "") 2049 #endif 2050 ); 2051 else 2052 fprintf(stderr, 2053 "%s: %s proto=%s%s, wait.max=%d.%d, user:group=%s:%s builtin=%lx server=%s" 2054 #ifdef IPSEC 2055 " policy=%s" 2056 #endif 2057 "\n", 2058 action, sep->se_service, 2059 sep->se_type == FAITH_TYPE ? "faith/" : "", 2060 sep->se_proto, 2061 sep->se_wait, sep->se_max, sep->se_user, sep->se_group, 2062 (long)sep->se_bi, sep->se_server 2063 #ifdef IPSEC 2064 , (sep->se_policy ? sep->se_policy : "") 2065 #endif 2066 ); 2067 } 2068 2069 static void 2070 usage(void) 2071 { 2072 #ifdef LIBWRAP 2073 (void)fprintf(stderr, "usage: %s [-dl] [conf]\n", getprogname()); 2074 #else 2075 (void)fprintf(stderr, "usage: %s [-d] [conf]\n", getprogname()); 2076 #endif 2077 exit(1); 2078 } 2079 2080 2081 /* 2082 * Based on TCPMUX.C by Mark K. Lottor November 1988 2083 * sri-nic::ps:<mkl>tcpmux.c 2084 */ 2085 2086 static int /* # of characters upto \r,\n or \0 */ 2087 get_line(int fd, char *buf, int len) 2088 { 2089 int count = 0; 2090 ssize_t n; 2091 2092 do { 2093 n = read(fd, buf, len-count); 2094 if (n == 0) 2095 return (count); 2096 if (n < 0) 2097 return (-1); 2098 while (--n >= 0) { 2099 if (*buf == '\r' || *buf == '\n' || *buf == '\0') 2100 return (count); 2101 count++; 2102 buf++; 2103 } 2104 } while (count < len); 2105 return (count); 2106 } 2107 2108 #define MAX_SERV_LEN (256+2) /* 2 bytes for \r\n */ 2109 2110 #define strwrite(fd, buf) (void) write(fd, buf, sizeof(buf)-1) 2111 2112 static void 2113 tcpmux(int ctrl, struct servtab *sep) 2114 { 2115 char service[MAX_SERV_LEN+1]; 2116 int len; 2117 2118 /* Get requested service name */ 2119 if ((len = get_line(ctrl, service, MAX_SERV_LEN)) < 0) { 2120 strwrite(ctrl, "-Error reading service name\r\n"); 2121 goto reject; 2122 } 2123 service[len] = '\0'; 2124 2125 if (debug) 2126 fprintf(stderr, "tcpmux: someone wants %s\n", service); 2127 2128 /* 2129 * Help is a required command, and lists available services, 2130 * one per line. 2131 */ 2132 if (!strcasecmp(service, "help")) { 2133 strwrite(ctrl, "+Available services:\r\n"); 2134 strwrite(ctrl, "help\r\n"); 2135 for (sep = servtab; sep != NULL; sep = sep->se_next) { 2136 if (!ISMUX(sep)) 2137 continue; 2138 (void)write(ctrl, sep->se_service, 2139 strlen(sep->se_service)); 2140 strwrite(ctrl, "\r\n"); 2141 } 2142 goto reject; 2143 } 2144 2145 /* Try matching a service in inetd.conf with the request */ 2146 for (sep = servtab; sep != NULL; sep = sep->se_next) { 2147 if (!ISMUX(sep)) 2148 continue; 2149 if (!strcasecmp(service, sep->se_service)) { 2150 if (ISMUXPLUS(sep)) 2151 strwrite(ctrl, "+Go\r\n"); 2152 run_service(ctrl, sep, 1 /* forked */); 2153 return; 2154 } 2155 } 2156 strwrite(ctrl, "-Service not available\r\n"); 2157 reject: 2158 _exit(1); 2159 } 2160 2161 /* 2162 * check if the address/port where send data to is one of the obvious ports 2163 * that are used for denial of service attacks like two echo ports 2164 * just echoing data between them 2165 */ 2166 static int 2167 port_good_dg(struct sockaddr *sa) 2168 { 2169 struct in_addr in; 2170 struct sockaddr_in *sin; 2171 #ifdef INET6 2172 struct in6_addr *in6; 2173 struct sockaddr_in6 *sin6; 2174 #endif 2175 u_int16_t port; 2176 int i; 2177 char hbuf[NI_MAXHOST]; 2178 2179 switch (sa->sa_family) { 2180 case AF_INET: 2181 sin = (struct sockaddr_in *)(void *)sa; 2182 in.s_addr = ntohl(sin->sin_addr.s_addr); 2183 port = ntohs(sin->sin_port); 2184 #ifdef INET6 2185 v4chk: 2186 #endif 2187 if (IN_MULTICAST(in.s_addr)) 2188 goto bad; 2189 switch ((in.s_addr & 0xff000000) >> 24) { 2190 case 0: case 127: case 255: 2191 goto bad; 2192 } 2193 if (dg_broadcast(&in)) 2194 goto bad; 2195 break; 2196 #ifdef INET6 2197 case AF_INET6: 2198 sin6 = (struct sockaddr_in6 *)(void *)sa; 2199 in6 = &sin6->sin6_addr; 2200 port = ntohs(sin6->sin6_port); 2201 if (IN6_IS_ADDR_MULTICAST(in6) || IN6_IS_ADDR_UNSPECIFIED(in6)) 2202 goto bad; 2203 if (IN6_IS_ADDR_V4MAPPED(in6) || IN6_IS_ADDR_V4COMPAT(in6)) { 2204 memcpy(&in, &in6->s6_addr[12], sizeof(in)); 2205 in.s_addr = ntohl(in.s_addr); 2206 goto v4chk; 2207 } 2208 break; 2209 #endif 2210 default: 2211 /* XXX unsupported af, is it safe to assume it to be safe? */ 2212 return (1); 2213 } 2214 2215 for (i = 0; bad_ports[i] != 0; i++) { 2216 if (port == bad_ports[i]) 2217 goto bad; 2218 } 2219 2220 return (1); 2221 2222 bad: 2223 if (getnameinfo(sa, sa->sa_len, hbuf, (socklen_t)sizeof(hbuf), NULL, 0, 2224 niflags) != 0) 2225 strlcpy(hbuf, "?", sizeof(hbuf)); 2226 syslog(LOG_WARNING,"Possible DoS attack from %s, Port %d", 2227 hbuf, port); 2228 return (0); 2229 } 2230 2231 /* XXX need optimization */ 2232 static int 2233 dg_broadcast(struct in_addr *in) 2234 { 2235 struct ifaddrs *ifa, *ifap; 2236 struct sockaddr_in *sin; 2237 2238 if (getifaddrs(&ifap) < 0) 2239 return (0); 2240 for (ifa = ifap; ifa; ifa = ifa->ifa_next) { 2241 if (ifa->ifa_addr->sa_family != AF_INET || 2242 (ifa->ifa_flags & IFF_BROADCAST) == 0) 2243 continue; 2244 sin = (struct sockaddr_in *)(void *)ifa->ifa_broadaddr; 2245 if (sin->sin_addr.s_addr == in->s_addr) { 2246 freeifaddrs(ifap); 2247 return (1); 2248 } 2249 } 2250 freeifaddrs(ifap); 2251 return (0); 2252 } 2253 2254 static int 2255 my_kevent(const struct kevent *changelist, size_t nchanges, 2256 struct kevent *eventlist, size_t nevents) 2257 { 2258 int result; 2259 2260 while ((result = kevent(kq, changelist, nchanges, eventlist, nevents, 2261 NULL)) < 0) 2262 if (errno != EINTR) { 2263 syslog(LOG_ERR, "kevent: %m"); 2264 exit(EXIT_FAILURE); 2265 } 2266 2267 return (result); 2268 } 2269 2270 static struct kevent * 2271 allocchange(void) 2272 { 2273 if (changes == A_CNT(changebuf)) { 2274 (void) my_kevent(changebuf, A_CNT(changebuf), NULL, 0); 2275 changes = 0; 2276 } 2277 2278 return (&changebuf[changes++]); 2279 } 2280