inetd.c revision 1.107
1 /* $NetBSD: inetd.c,v 1.107 2008/08/04 03:55:48 tls 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 1.107 2008/08/04 03:55:48 tls 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 RLIMIT_NOFILE 198 #define RLIMIT_NOFILE RLIMIT_OFILE 199 #endif 200 201 #ifndef NO_RPC 202 #define RPC 203 #endif 204 205 #include <net/if.h> 206 207 #include <netinet/in.h> 208 #include <arpa/inet.h> 209 #ifdef RPC 210 #include <rpc/rpc.h> 211 #include <rpc/rpcb_clnt.h> 212 #include <netconfig.h> 213 #endif 214 215 #include <ctype.h> 216 #include <errno.h> 217 #include <fcntl.h> 218 #include <grp.h> 219 #include <netdb.h> 220 #include <pwd.h> 221 #include <signal.h> 222 #include <stdio.h> 223 #include <stdlib.h> 224 #include <string.h> 225 #include <syslog.h> 226 #include <unistd.h> 227 #include <util.h> 228 #include <ifaddrs.h> 229 230 #include "pathnames.h" 231 232 #ifdef IPSEC 233 #include <netinet6/ipsec.h> 234 #ifndef IPSEC_POLICY_IPSEC /* no ipsec support on old ipsec */ 235 #undef IPSEC 236 #endif 237 #include "ipsec.h" 238 #endif 239 240 #ifdef LIBWRAP 241 # include <tcpd.h> 242 #ifndef LIBWRAP_ALLOW_FACILITY 243 # define LIBWRAP_ALLOW_FACILITY LOG_AUTH 244 #endif 245 #ifndef LIBWRAP_ALLOW_SEVERITY 246 # define LIBWRAP_ALLOW_SEVERITY LOG_INFO 247 #endif 248 #ifndef LIBWRAP_DENY_FACILITY 249 # define LIBWRAP_DENY_FACILITY LOG_AUTH 250 #endif 251 #ifndef LIBWRAP_DENY_SEVERITY 252 # define LIBWRAP_DENY_SEVERITY LOG_WARNING 253 #endif 254 int allow_severity = LIBWRAP_ALLOW_FACILITY|LIBWRAP_ALLOW_SEVERITY; 255 int deny_severity = LIBWRAP_DENY_FACILITY|LIBWRAP_DENY_SEVERITY; 256 #endif 257 258 #define TOOMANY 40 /* don't start more than TOOMANY */ 259 #define CNT_INTVL 60 /* servers in CNT_INTVL sec. */ 260 #define RETRYTIME (60*10) /* retry after bind or server fail */ 261 262 #define A_CNT(a) (sizeof (a) / sizeof (a[0])) 263 264 int debug; 265 #ifdef LIBWRAP 266 int lflag; 267 #endif 268 int maxsock; 269 int kq; 270 int options; 271 int timingout; 272 struct servent *sp; 273 char *curdom; 274 const int niflags = NI_NUMERICHOST | NI_NUMERICSERV; 275 276 #ifndef OPEN_MAX 277 #define OPEN_MAX 64 278 #endif 279 280 /* Reserve some descriptors, 3 stdio + at least: 1 log, 1 conf. file */ 281 #define FD_MARGIN (8) 282 rlim_t rlim_ofile_cur = OPEN_MAX; 283 284 #ifdef RLIMIT_NOFILE 285 struct rlimit rlim_ofile; 286 #endif 287 288 struct kevent changebuf[64]; 289 size_t changes; 290 291 struct servtab { 292 char *se_hostaddr; /* host address to listen on */ 293 char *se_service; /* name of service */ 294 int se_socktype; /* type of socket to use */ 295 int se_family; /* address family */ 296 char *se_proto; /* protocol used */ 297 int se_sndbuf; /* sndbuf size */ 298 int se_rcvbuf; /* rcvbuf size */ 299 int se_rpcprog; /* rpc program number */ 300 int se_rpcversl; /* rpc program lowest version */ 301 int se_rpcversh; /* rpc program highest version */ 302 #define isrpcservice(sep) ((sep)->se_rpcversl != 0) 303 pid_t se_wait; /* single threaded server */ 304 short se_checked; /* looked at during merge */ 305 char *se_user; /* user name to run as */ 306 char *se_group; /* group name to run as */ 307 struct biltin *se_bi; /* if built-in, description */ 308 char *se_server; /* server program */ 309 #define MAXARGV 20 310 char *se_argv[MAXARGV+1]; /* program arguments */ 311 #ifdef IPSEC 312 char *se_policy; /* IPsec poilcy string */ 313 #endif 314 struct accept_filter_arg se_accf; /* accept filter for stream service */ 315 int se_fd; /* open descriptor */ 316 int se_type; /* type */ 317 union { 318 struct sockaddr se_un_ctrladdr; 319 struct sockaddr_in se_un_ctrladdr_in; 320 struct sockaddr_in6 se_un_ctrladdr_in6; 321 struct sockaddr_un se_un_ctrladdr_un; 322 } se_un; /* bound address */ 323 #define se_ctrladdr se_un.se_un_ctrladdr 324 #define se_ctrladdr_in se_un.se_un_ctrladdr_in 325 #define se_ctrladdr_un se_un.se_un_ctrladdr_un 326 int se_ctrladdr_size; 327 int se_max; /* max # of instances of this service */ 328 int se_count; /* number started since se_time */ 329 struct timeval se_time; /* start of se_count */ 330 #ifdef MULOG 331 int se_log; 332 #define MULOG_RFC931 0x40000000 333 #endif 334 struct servtab *se_next; 335 } *servtab; 336 337 #define NORM_TYPE 0 338 #define MUX_TYPE 1 339 #define MUXPLUS_TYPE 2 340 #define FAITH_TYPE 3 341 #define ISMUX(sep) (((sep)->se_type == MUX_TYPE) || \ 342 ((sep)->se_type == MUXPLUS_TYPE)) 343 #define ISMUXPLUS(sep) ((sep)->se_type == MUXPLUS_TYPE) 344 345 346 static void chargen_dg(int, struct servtab *); 347 static void chargen_stream(int, struct servtab *); 348 static void close_sep(struct servtab *); 349 static void config(void); 350 static void daytime_dg(int, struct servtab *); 351 static void daytime_stream(int, struct servtab *); 352 static void discard_dg(int, struct servtab *); 353 static void discard_stream(int, struct servtab *); 354 static void echo_dg(int, struct servtab *); 355 static void echo_stream(int, struct servtab *); 356 static void endconfig(void); 357 static struct servtab *enter(struct servtab *); 358 static void freeconfig(struct servtab *); 359 static struct servtab *getconfigent(void); 360 static void goaway(void); 361 static void machtime_dg(int, struct servtab *); 362 static void machtime_stream(int, struct servtab *); 363 static char *newstr(char *); 364 static char *nextline(FILE *); 365 static void print_service(char *, struct servtab *); 366 static void reapchild(void); 367 static void retry(void); 368 static void run_service(int, struct servtab *, int); 369 static int setconfig(void); 370 static void setup(struct servtab *); 371 static char *sskip(char **); 372 static char *skip(char **); 373 static void tcpmux(int, struct servtab *); 374 static void usage(void); 375 static void register_rpc(struct servtab *); 376 static void unregister_rpc(struct servtab *); 377 static void bump_nofile(void); 378 static void inetd_setproctitle(char *, int); 379 static void initring(void); 380 static uint32_t machtime(void); 381 static int port_good_dg(struct sockaddr *); 382 static int dg_broadcast(struct in_addr *); 383 static int my_kevent(const struct kevent *, size_t, struct kevent *, 384 size_t); 385 static struct kevent * allocchange(void); 386 static int getline(int, char *, int); 387 static void spawn(struct servtab *, int); 388 #ifdef MULOG 389 static void dolog(struct servtab *, int); 390 static void timeout(int); 391 static char *rfc931_name(struct sockaddr *, int); 392 #endif 393 394 struct biltin { 395 char *bi_service; /* internally provided service name */ 396 int bi_socktype; /* type of socket supported */ 397 short bi_fork; /* 1 if should fork before call */ 398 short bi_wait; /* 1 if should wait for child */ 399 void (*bi_fn)(int, struct servtab *); 400 /* function which performs it */ 401 } biltins[] = { 402 /* Echo received data */ 403 { "echo", SOCK_STREAM, 1, 0, echo_stream }, 404 { "echo", SOCK_DGRAM, 0, 0, echo_dg }, 405 406 /* Internet /dev/null */ 407 { "discard", SOCK_STREAM, 1, 0, discard_stream }, 408 { "discard", SOCK_DGRAM, 0, 0, discard_dg }, 409 410 /* Return 32 bit time since 1970 */ 411 { "time", SOCK_STREAM, 0, 0, machtime_stream }, 412 { "time", SOCK_DGRAM, 0, 0, machtime_dg }, 413 414 /* Return human-readable time */ 415 { "daytime", SOCK_STREAM, 0, 0, daytime_stream }, 416 { "daytime", SOCK_DGRAM, 0, 0, daytime_dg }, 417 418 /* Familiar character generator */ 419 { "chargen", SOCK_STREAM, 1, 0, chargen_stream }, 420 { "chargen", SOCK_DGRAM, 0, 0, chargen_dg }, 421 422 { "tcpmux", SOCK_STREAM, 1, 0, tcpmux }, 423 424 { NULL } 425 }; 426 427 /* list of "bad" ports. I.e. ports that are most obviously used for 428 * "cycling packets" denial of service attacks. See /etc/services. 429 * List must end with port number "0". 430 */ 431 432 u_int16_t bad_ports[] = { 7, 9, 13, 19, 37, 0 }; 433 434 435 #define NUMINT (sizeof(intab) / sizeof(struct inent)) 436 char *CONFIG = _PATH_INETDCONF; 437 438 static int my_signals[] = 439 { SIGALRM, SIGHUP, SIGCHLD, SIGTERM, SIGINT, SIGPIPE }; 440 441 int 442 main(int argc, char *argv[]) 443 { 444 int ch, n, reload = 1; 445 446 while ((ch = getopt(argc, argv, 447 #ifdef LIBWRAP 448 "dl" 449 #else 450 "d" 451 #endif 452 )) != -1) 453 switch(ch) { 454 case 'd': 455 debug = 1; 456 options |= SO_DEBUG; 457 break; 458 #ifdef LIBWRAP 459 case 'l': 460 lflag = 1; 461 break; 462 #endif 463 case '?': 464 default: 465 usage(); 466 } 467 argc -= optind; 468 argv += optind; 469 470 if (argc > 0) 471 CONFIG = argv[0]; 472 473 if (!debug) 474 daemon(0, 0); 475 openlog("inetd", LOG_PID | LOG_NOWAIT, LOG_DAEMON); 476 pidfile(NULL); 477 478 kq = kqueue(); 479 if (kq < 0) { 480 syslog(LOG_ERR, "kqueue: %m"); 481 return (EXIT_FAILURE); 482 } 483 484 #ifdef RLIMIT_NOFILE 485 if (getrlimit(RLIMIT_NOFILE, &rlim_ofile) < 0) { 486 syslog(LOG_ERR, "getrlimit: %m"); 487 } else { 488 rlim_ofile_cur = rlim_ofile.rlim_cur; 489 if (rlim_ofile_cur == RLIM_INFINITY) /* ! */ 490 rlim_ofile_cur = OPEN_MAX; 491 } 492 #endif 493 494 for (n = 0; n < (int)A_CNT(my_signals); n++) { 495 int signum; 496 497 signum = my_signals[n]; 498 if (signum != SIGCHLD) 499 (void) signal(signum, SIG_IGN); 500 501 if (signum != SIGPIPE) { 502 struct kevent *ev; 503 504 ev = allocchange(); 505 EV_SET(ev, signum, EVFILT_SIGNAL, EV_ADD | EV_ENABLE, 506 0, 0, 0); 507 } 508 } 509 510 for (;;) { 511 int ctrl; 512 struct kevent eventbuf[64], *ev; 513 struct servtab *sep; 514 515 if (reload) { 516 reload = 0; 517 config(); 518 } 519 520 n = my_kevent(changebuf, changes, eventbuf, A_CNT(eventbuf)); 521 changes = 0; 522 523 for (ev = eventbuf; n > 0; ev++, n--) { 524 if (ev->filter == EVFILT_SIGNAL) { 525 switch (ev->ident) { 526 case SIGALRM: 527 retry(); 528 break; 529 case SIGCHLD: 530 reapchild(); 531 break; 532 case SIGTERM: 533 case SIGINT: 534 goaway(); 535 break; 536 case SIGHUP: 537 reload = 1; 538 break; 539 } 540 continue; 541 } 542 if (ev->filter != EVFILT_READ) 543 continue; 544 sep = (struct servtab *)ev->udata; 545 /* Paranoia */ 546 if ((int)ev->ident != sep->se_fd) 547 continue; 548 if (debug) 549 fprintf(stderr, "someone wants %s\n", 550 sep->se_service); 551 if (!sep->se_wait && sep->se_socktype == SOCK_STREAM) { 552 /* XXX here do the libwrap check-before-accept*/ 553 ctrl = accept(sep->se_fd, NULL, NULL); 554 if (debug) 555 fprintf(stderr, "accept, ctrl %d\n", 556 ctrl); 557 if (ctrl < 0) { 558 if (errno != EINTR) 559 syslog(LOG_WARNING, 560 "accept (for %s): %m", 561 sep->se_service); 562 continue; 563 } 564 } else 565 ctrl = sep->se_fd; 566 spawn(sep, ctrl); 567 } 568 } 569 } 570 571 static void 572 spawn(struct servtab *sep, int ctrl) 573 { 574 int dofork; 575 pid_t pid; 576 577 pid = 0; 578 #ifdef LIBWRAP_INTERNAL 579 dofork = 1; 580 #else 581 dofork = (sep->se_bi == 0 || sep->se_bi->bi_fork); 582 #endif 583 if (dofork) { 584 if (sep->se_count++ == 0) 585 (void)gettimeofday(&sep->se_time, NULL); 586 else if (sep->se_count >= sep->se_max) { 587 struct timeval now; 588 589 (void)gettimeofday(&now, NULL); 590 if (now.tv_sec - sep->se_time.tv_sec > CNT_INTVL) { 591 sep->se_time = now; 592 sep->se_count = 1; 593 } else { 594 syslog(LOG_ERR, 595 "%s/%s max spawn rate (%d in %d seconds) " 596 "exceeded; service not started", 597 sep->se_service, sep->se_proto, 598 sep->se_max, CNT_INTVL); 599 if (!sep->se_wait && sep->se_socktype == 600 SOCK_STREAM) 601 close(ctrl); 602 close_sep(sep); 603 if (!timingout) { 604 timingout = 1; 605 alarm(RETRYTIME); 606 } 607 return; 608 } 609 } 610 pid = fork(); 611 if (pid < 0) { 612 syslog(LOG_ERR, "fork: %m"); 613 if (!sep->se_wait && sep->se_socktype == SOCK_STREAM) 614 close(ctrl); 615 sleep(1); 616 return; 617 } 618 if (pid != 0 && sep->se_wait) { 619 struct kevent *ev; 620 621 sep->se_wait = pid; 622 ev = allocchange(); 623 EV_SET(ev, sep->se_fd, EVFILT_READ, 624 EV_DELETE, 0, 0, 0); 625 } 626 if (pid == 0) { 627 size_t n; 628 629 for (n = 0; n < A_CNT(my_signals); n++) 630 (void) signal(my_signals[n], SIG_DFL); 631 if (debug) 632 setsid(); 633 } 634 } 635 if (pid == 0) { 636 run_service(ctrl, sep, dofork); 637 if (dofork) 638 exit(0); 639 } 640 if (!sep->se_wait && sep->se_socktype == SOCK_STREAM) 641 close(ctrl); 642 } 643 644 static void 645 run_service(int ctrl, struct servtab *sep, int didfork) 646 { 647 struct passwd *pwd; 648 struct group *grp = NULL; /* XXX gcc */ 649 char buf[NI_MAXSERV]; 650 struct servtab *s; 651 #ifdef LIBWRAP 652 struct request_info req; 653 int denied; 654 char *service = NULL; /* XXX gcc */ 655 #endif 656 657 #ifdef LIBWRAP 658 #ifndef LIBWRAP_INTERNAL 659 if (sep->se_bi == 0) 660 #endif 661 if (!sep->se_wait && sep->se_socktype == SOCK_STREAM) { 662 request_init(&req, RQ_DAEMON, sep->se_argv[0] ? 663 sep->se_argv[0] : sep->se_service, RQ_FILE, ctrl, NULL); 664 fromhost(&req); 665 denied = !hosts_access(&req); 666 if (denied || lflag) { 667 if (getnameinfo(&sep->se_ctrladdr, 668 sep->se_ctrladdr.sa_len, NULL, 0, 669 buf, sizeof(buf), 0) != 0) { 670 /* shouldn't happen */ 671 (void)snprintf(buf, sizeof buf, "%d", 672 ntohs(sep->se_ctrladdr_in.sin_port)); 673 } 674 service = buf; 675 } 676 if (denied) { 677 syslog(deny_severity, 678 "refused connection from %.500s, service %s (%s)", 679 eval_client(&req), service, sep->se_proto); 680 goto reject; 681 } 682 if (lflag) { 683 syslog(allow_severity, 684 "connection from %.500s, service %s (%s)", 685 eval_client(&req), service, sep->se_proto); 686 } 687 } 688 #endif /* LIBWRAP */ 689 690 if (sep->se_bi) { 691 if (didfork) { 692 for (s = servtab; s; s = s->se_next) 693 if (s->se_fd != -1 && s->se_fd != ctrl) 694 close(s->se_fd); 695 } 696 (*sep->se_bi->bi_fn)(ctrl, sep); 697 } else { 698 if ((pwd = getpwnam(sep->se_user)) == NULL) { 699 syslog(LOG_ERR, "%s/%s: %s: No such user", 700 sep->se_service, sep->se_proto, sep->se_user); 701 goto reject; 702 } 703 if (sep->se_group && 704 (grp = getgrnam(sep->se_group)) == NULL) { 705 syslog(LOG_ERR, "%s/%s: %s: No such group", 706 sep->se_service, sep->se_proto, sep->se_group); 707 goto reject; 708 } 709 if (pwd->pw_uid) { 710 if (sep->se_group) 711 pwd->pw_gid = grp->gr_gid; 712 if (setgid(pwd->pw_gid) < 0) { 713 syslog(LOG_ERR, 714 "%s/%s: can't set gid %d: %m", sep->se_service, 715 sep->se_proto, pwd->pw_gid); 716 goto reject; 717 } 718 (void) initgroups(pwd->pw_name, 719 pwd->pw_gid); 720 if (setuid(pwd->pw_uid) < 0) { 721 syslog(LOG_ERR, 722 "%s/%s: can't set uid %d: %m", sep->se_service, 723 sep->se_proto, pwd->pw_uid); 724 goto reject; 725 } 726 } else if (sep->se_group) { 727 (void) setgid((gid_t)grp->gr_gid); 728 } 729 if (debug) 730 fprintf(stderr, "%d execl %s\n", 731 getpid(), sep->se_server); 732 #ifdef MULOG 733 if (sep->se_log) 734 dolog(sep, ctrl); 735 #endif 736 /* Set our control descriptor to not close-on-exec... */ 737 if (fcntl(ctrl, F_SETFD, 0) < 0) 738 syslog(LOG_ERR, "fcntl (F_SETFD, 0): %m"); 739 /* ...and dup it to stdin, stdout, and stderr. */ 740 if (ctrl != 0) { 741 dup2(ctrl, 0); 742 close(ctrl); 743 ctrl = 0; 744 } 745 dup2(0, 1); 746 dup2(0, 2); 747 #ifdef RLIMIT_NOFILE 748 if (rlim_ofile.rlim_cur != rlim_ofile_cur && 749 setrlimit(RLIMIT_NOFILE, &rlim_ofile) < 0) 750 syslog(LOG_ERR, "setrlimit: %m"); 751 #endif 752 execv(sep->se_server, sep->se_argv); 753 syslog(LOG_ERR, "cannot execute %s: %m", sep->se_server); 754 reject: 755 if (sep->se_socktype != SOCK_STREAM) 756 recv(ctrl, buf, sizeof (buf), 0); 757 _exit(1); 758 } 759 } 760 761 static void 762 reapchild(void) 763 { 764 int status; 765 pid_t pid; 766 struct servtab *sep; 767 768 for (;;) { 769 pid = wait3(&status, WNOHANG, NULL); 770 if (pid <= 0) 771 break; 772 if (debug) 773 (void) fprintf(stderr, "%d reaped, status %#x\n", 774 pid, status); 775 for (sep = servtab; sep != NULL; sep = sep->se_next) 776 if (sep->se_wait == pid) { 777 struct kevent *ev; 778 779 if (WIFEXITED(status) && WEXITSTATUS(status)) 780 syslog(LOG_WARNING, 781 "%s: exit status 0x%x", 782 sep->se_server, WEXITSTATUS(status)); 783 else if (WIFSIGNALED(status)) 784 syslog(LOG_WARNING, 785 "%s: exit signal 0x%x", 786 sep->se_server, WTERMSIG(status)); 787 sep->se_wait = 1; 788 ev = allocchange(); 789 EV_SET(ev, sep->se_fd, EVFILT_READ, 790 EV_ADD | EV_ENABLE, 0, 0, (intptr_t)sep); 791 if (debug) 792 fprintf(stderr, "restored %s, fd %d\n", 793 sep->se_service, sep->se_fd); 794 } 795 } 796 } 797 798 static void 799 config(void) 800 { 801 struct servtab *sep, *cp, **sepp; 802 size_t n; 803 804 if (!setconfig()) { 805 syslog(LOG_ERR, "%s: %m", CONFIG); 806 return; 807 } 808 for (sep = servtab; sep != NULL; sep = sep->se_next) 809 sep->se_checked = 0; 810 while ((cp = getconfigent())) { 811 for (sep = servtab; sep != NULL; sep = sep->se_next) 812 if (strcmp(sep->se_service, cp->se_service) == 0 && 813 strcmp(sep->se_hostaddr, cp->se_hostaddr) == 0 && 814 strcmp(sep->se_proto, cp->se_proto) == 0 && 815 ISMUX(sep) == ISMUX(cp)) 816 break; 817 if (sep != NULL) { 818 int i; 819 820 #define SWAP(type, a, b) {type c = a; a = b; b = c;} 821 822 /* 823 * sep->se_wait may be holding the pid of a daemon 824 * that we're waiting for. If so, don't overwrite 825 * it unless the config file explicitly says don't 826 * wait. 827 */ 828 if (cp->se_bi == 0 && 829 (sep->se_wait == 1 || cp->se_wait == 0)) 830 sep->se_wait = cp->se_wait; 831 SWAP(char *, sep->se_user, cp->se_user); 832 SWAP(char *, sep->se_group, cp->se_group); 833 SWAP(char *, sep->se_server, cp->se_server); 834 for (i = 0; i < MAXARGV; i++) 835 SWAP(char *, sep->se_argv[i], cp->se_argv[i]); 836 #ifdef IPSEC 837 SWAP(char *, sep->se_policy, cp->se_policy); 838 #endif 839 SWAP(int, cp->se_type, sep->se_type); 840 SWAP(int, cp->se_max, sep->se_max); 841 #undef SWAP 842 if (isrpcservice(sep)) 843 unregister_rpc(sep); 844 sep->se_rpcversl = cp->se_rpcversl; 845 sep->se_rpcversh = cp->se_rpcversh; 846 freeconfig(cp); 847 if (debug) 848 print_service("REDO", sep); 849 } else { 850 sep = enter(cp); 851 if (debug) 852 print_service("ADD ", sep); 853 } 854 sep->se_checked = 1; 855 856 switch (sep->se_family) { 857 case AF_LOCAL: 858 if (sep->se_fd != -1) 859 break; 860 n = strlen(sep->se_service); 861 if (n > sizeof(sep->se_ctrladdr_un.sun_path)) { 862 syslog(LOG_ERR, "%s: address too long", 863 sep->se_service); 864 sep->se_checked = 0; 865 continue; 866 } 867 (void)unlink(sep->se_service); 868 strncpy(sep->se_ctrladdr_un.sun_path, 869 sep->se_service, n); 870 sep->se_ctrladdr_un.sun_family = AF_LOCAL; 871 sep->se_ctrladdr_size = n + 872 sizeof(sep->se_ctrladdr_un) - 873 sizeof(sep->se_ctrladdr_un.sun_path); 874 if (!ISMUX(sep)) 875 setup(sep); 876 break; 877 case AF_INET: 878 #ifdef INET6 879 case AF_INET6: 880 #endif 881 { 882 struct addrinfo hints, *res; 883 char *host, *port; 884 int error; 885 int s; 886 887 /* check if the family is supported */ 888 s = socket(sep->se_family, SOCK_DGRAM, 0); 889 if (s < 0) { 890 syslog(LOG_WARNING, 891 "%s/%s: %s: the address family is not " 892 "supported by the kernel", 893 sep->se_service, sep->se_proto, 894 sep->se_hostaddr); 895 sep->se_checked = 0; 896 continue; 897 } 898 close(s); 899 900 memset(&hints, 0, sizeof(hints)); 901 hints.ai_family = sep->se_family; 902 hints.ai_socktype = sep->se_socktype; 903 hints.ai_flags = AI_PASSIVE; 904 if (!strcmp(sep->se_hostaddr, "*")) 905 host = NULL; 906 else 907 host = sep->se_hostaddr; 908 if (isrpcservice(sep) || ISMUX(sep)) 909 port = "0"; 910 else 911 port = sep->se_service; 912 error = getaddrinfo(host, port, &hints, &res); 913 if (error) { 914 if (error == EAI_SERVICE) { 915 /* gai_strerror not friendly enough */ 916 syslog(LOG_WARNING, "%s/%s: " 917 "unknown service", 918 sep->se_service, sep->se_proto); 919 } else { 920 syslog(LOG_ERR, "%s/%s: %s: %s", 921 sep->se_service, sep->se_proto, 922 sep->se_hostaddr, 923 gai_strerror(error)); 924 } 925 sep->se_checked = 0; 926 continue; 927 } 928 if (res->ai_next) { 929 syslog(LOG_ERR, 930 "%s/%s: %s: resolved to multiple addr", 931 sep->se_service, sep->se_proto, 932 sep->se_hostaddr); 933 sep->se_checked = 0; 934 freeaddrinfo(res); 935 continue; 936 } 937 memcpy(&sep->se_ctrladdr, res->ai_addr, 938 res->ai_addrlen); 939 if (ISMUX(sep)) { 940 sep->se_fd = -1; 941 freeaddrinfo(res); 942 continue; 943 } 944 sep->se_ctrladdr_size = res->ai_addrlen; 945 freeaddrinfo(res); 946 #ifdef RPC 947 if (isrpcservice(sep)) { 948 struct rpcent *rp; 949 950 sep->se_rpcprog = atoi(sep->se_service); 951 if (sep->se_rpcprog == 0) { 952 rp = getrpcbyname(sep->se_service); 953 if (rp == 0) { 954 syslog(LOG_ERR, 955 "%s/%s: unknown service", 956 sep->se_service, 957 sep->se_proto); 958 sep->se_checked = 0; 959 continue; 960 } 961 sep->se_rpcprog = rp->r_number; 962 } 963 if (sep->se_fd == -1 && !ISMUX(sep)) 964 setup(sep); 965 if (sep->se_fd != -1) 966 register_rpc(sep); 967 } else 968 #endif 969 { 970 if (sep->se_fd >= 0) 971 close_sep(sep); 972 if (sep->se_fd == -1 && !ISMUX(sep)) 973 setup(sep); 974 } 975 } 976 } 977 } 978 endconfig(); 979 /* 980 * Purge anything not looked at above. 981 */ 982 sepp = &servtab; 983 while ((sep = *sepp)) { 984 if (sep->se_checked) { 985 sepp = &sep->se_next; 986 continue; 987 } 988 *sepp = sep->se_next; 989 if (sep->se_fd >= 0) 990 close_sep(sep); 991 if (isrpcservice(sep)) 992 unregister_rpc(sep); 993 if (sep->se_family == AF_LOCAL) 994 (void)unlink(sep->se_service); 995 if (debug) 996 print_service("FREE", sep); 997 freeconfig(sep); 998 free(sep); 999 } 1000 } 1001 1002 static void 1003 retry(void) 1004 { 1005 struct servtab *sep; 1006 1007 timingout = 0; 1008 for (sep = servtab; sep != NULL; sep = sep->se_next) { 1009 if (sep->se_fd == -1 && !ISMUX(sep)) { 1010 switch (sep->se_family) { 1011 case AF_LOCAL: 1012 case AF_INET: 1013 #ifdef INET6 1014 case AF_INET6: 1015 #endif 1016 setup(sep); 1017 if (sep->se_fd != -1 && isrpcservice(sep)) 1018 register_rpc(sep); 1019 break; 1020 } 1021 } 1022 } 1023 } 1024 1025 static void 1026 goaway(void) 1027 { 1028 struct servtab *sep; 1029 1030 for (sep = servtab; sep != NULL; sep = sep->se_next) { 1031 if (sep->se_fd == -1) 1032 continue; 1033 1034 switch (sep->se_family) { 1035 case AF_LOCAL: 1036 (void)unlink(sep->se_service); 1037 break; 1038 case AF_INET: 1039 #ifdef INET6 1040 case AF_INET6: 1041 #endif 1042 if (sep->se_wait == 1 && isrpcservice(sep)) 1043 unregister_rpc(sep); 1044 break; 1045 } 1046 (void)close(sep->se_fd); 1047 } 1048 exit(0); 1049 } 1050 1051 static void 1052 setup(struct servtab *sep) 1053 { 1054 int on = 1; 1055 #ifdef INET6 1056 int off = 0; 1057 #endif 1058 struct kevent *ev; 1059 1060 if ((sep->se_fd = socket(sep->se_family, sep->se_socktype, 0)) < 0) { 1061 if (debug) 1062 fprintf(stderr, "socket failed on %s/%s: %s\n", 1063 sep->se_service, sep->se_proto, strerror(errno)); 1064 syslog(LOG_ERR, "%s/%s: socket: %m", 1065 sep->se_service, sep->se_proto); 1066 return; 1067 } 1068 /* Set all listening sockets to close-on-exec. */ 1069 if (fcntl(sep->se_fd, F_SETFD, FD_CLOEXEC) < 0) { 1070 syslog(LOG_ERR, "%s/%s: fcntl(F_SETFD, FD_CLOEXEC): %m", 1071 sep->se_service, sep->se_proto); 1072 close(sep->se_fd); 1073 return; 1074 } 1075 1076 #define turnon(fd, opt) \ 1077 setsockopt(fd, SOL_SOCKET, opt, (char *)&on, sizeof (on)) 1078 if (strcmp(sep->se_proto, "tcp") == 0 && (options & SO_DEBUG) && 1079 turnon(sep->se_fd, SO_DEBUG) < 0) 1080 syslog(LOG_ERR, "setsockopt (SO_DEBUG): %m"); 1081 if (turnon(sep->se_fd, SO_REUSEADDR) < 0) 1082 syslog(LOG_ERR, "setsockopt (SO_REUSEADDR): %m"); 1083 #undef turnon 1084 1085 /* Set the socket buffer sizes, if specified. */ 1086 if (sep->se_sndbuf != 0 && setsockopt(sep->se_fd, SOL_SOCKET, 1087 SO_SNDBUF, (char *)&sep->se_sndbuf, sizeof(sep->se_sndbuf)) < 0) 1088 syslog(LOG_ERR, "setsockopt (SO_SNDBUF %d): %m", 1089 sep->se_sndbuf); 1090 if (sep->se_rcvbuf != 0 && setsockopt(sep->se_fd, SOL_SOCKET, 1091 SO_RCVBUF, (char *)&sep->se_rcvbuf, sizeof(sep->se_rcvbuf)) < 0) 1092 syslog(LOG_ERR, "setsockopt (SO_RCVBUF %d): %m", 1093 sep->se_rcvbuf); 1094 #ifdef INET6 1095 if (sep->se_family == AF_INET6) { 1096 int *v; 1097 v = (sep->se_type == FAITH_TYPE) ? &on : &off; 1098 if (setsockopt(sep->se_fd, IPPROTO_IPV6, IPV6_FAITH, 1099 (char *)v, sizeof(*v)) < 0) 1100 syslog(LOG_ERR, "setsockopt (IPV6_FAITH): %m"); 1101 } 1102 #endif 1103 #ifdef IPSEC 1104 if (ipsecsetup(sep->se_family, sep->se_fd, sep->se_policy) < 0 && 1105 sep->se_policy) { 1106 syslog(LOG_ERR, "%s/%s: ipsec setup failed", 1107 sep->se_service, sep->se_proto); 1108 (void)close(sep->se_fd); 1109 sep->se_fd = -1; 1110 return; 1111 } 1112 #endif 1113 1114 if (bind(sep->se_fd, &sep->se_ctrladdr, sep->se_ctrladdr_size) < 0) { 1115 if (debug) 1116 fprintf(stderr, "bind failed on %s/%s: %s\n", 1117 sep->se_service, sep->se_proto, strerror(errno)); 1118 syslog(LOG_ERR, "%s/%s: bind: %m", 1119 sep->se_service, sep->se_proto); 1120 (void) close(sep->se_fd); 1121 sep->se_fd = -1; 1122 if (!timingout) { 1123 timingout = 1; 1124 alarm(RETRYTIME); 1125 } 1126 return; 1127 } 1128 if (sep->se_socktype == SOCK_STREAM) 1129 listen(sep->se_fd, 10); 1130 1131 /* Set the accept filter, if specified. To be done after listen.*/ 1132 if (sep->se_accf.af_name[0] != 0 && setsockopt(sep->se_fd, SOL_SOCKET, 1133 SO_ACCEPTFILTER, (char *)&sep->se_accf, 1134 sizeof(sep->se_accf)) < 0) 1135 syslog(LOG_ERR, "setsockopt(SO_ACCEPTFILTER %s): %m", 1136 sep->se_accf.af_name); 1137 1138 ev = allocchange(); 1139 EV_SET(ev, sep->se_fd, EVFILT_READ, EV_ADD | EV_ENABLE, 0, 0, 1140 (intptr_t)sep); 1141 if (sep->se_fd > maxsock) { 1142 maxsock = sep->se_fd; 1143 if (maxsock > rlim_ofile_cur - FD_MARGIN) 1144 bump_nofile(); 1145 } 1146 if (debug) 1147 fprintf(stderr, "registered %s on %d\n", 1148 sep->se_server, sep->se_fd); 1149 } 1150 1151 /* 1152 * Finish with a service and its socket. 1153 */ 1154 static void 1155 close_sep(struct servtab *sep) 1156 { 1157 if (sep->se_fd >= 0) { 1158 (void) close(sep->se_fd); 1159 sep->se_fd = -1; 1160 } 1161 sep->se_count = 0; 1162 } 1163 1164 static void 1165 register_rpc(struct servtab *sep) 1166 { 1167 #ifdef RPC 1168 struct netbuf nbuf; 1169 struct sockaddr_storage ss; 1170 struct netconfig *nconf; 1171 socklen_t socklen; 1172 int n; 1173 1174 if ((nconf = getnetconfigent(sep->se_proto+4)) == NULL) { 1175 syslog(LOG_ERR, "%s: getnetconfigent failed", 1176 sep->se_proto); 1177 return; 1178 } 1179 socklen = sizeof ss; 1180 if (getsockname(sep->se_fd, (struct sockaddr *)&ss, &socklen) < 0) { 1181 syslog(LOG_ERR, "%s/%s: getsockname: %m", 1182 sep->se_service, sep->se_proto); 1183 return; 1184 } 1185 1186 nbuf.buf = &ss; 1187 nbuf.len = ss.ss_len; 1188 nbuf.maxlen = sizeof (struct sockaddr_storage); 1189 for (n = sep->se_rpcversl; n <= sep->se_rpcversh; n++) { 1190 if (debug) 1191 fprintf(stderr, "rpcb_set: %u %d %s %s\n", 1192 sep->se_rpcprog, n, nconf->nc_netid, 1193 taddr2uaddr(nconf, &nbuf)); 1194 (void)rpcb_unset(sep->se_rpcprog, n, nconf); 1195 if (!rpcb_set(sep->se_rpcprog, n, nconf, &nbuf)) 1196 syslog(LOG_ERR, "rpcb_set: %u %d %s %s%s", 1197 sep->se_rpcprog, n, nconf->nc_netid, 1198 taddr2uaddr(nconf, &nbuf), clnt_spcreateerror("")); 1199 } 1200 #endif /* RPC */ 1201 } 1202 1203 static void 1204 unregister_rpc(struct servtab *sep) 1205 { 1206 #ifdef RPC 1207 int n; 1208 struct netconfig *nconf; 1209 1210 if ((nconf = getnetconfigent(sep->se_proto+4)) == NULL) { 1211 syslog(LOG_ERR, "%s: getnetconfigent failed", 1212 sep->se_proto); 1213 return; 1214 } 1215 1216 for (n = sep->se_rpcversl; n <= sep->se_rpcversh; n++) { 1217 if (debug) 1218 fprintf(stderr, "rpcb_unset(%u, %d, %s)\n", 1219 sep->se_rpcprog, n, nconf->nc_netid); 1220 if (!rpcb_unset(sep->se_rpcprog, n, nconf)) 1221 syslog(LOG_ERR, "rpcb_unset(%u, %d, %s) failed\n", 1222 sep->se_rpcprog, n, nconf->nc_netid); 1223 } 1224 #endif /* RPC */ 1225 } 1226 1227 1228 static struct servtab * 1229 enter(struct servtab *cp) 1230 { 1231 struct servtab *sep; 1232 1233 sep = (struct servtab *)malloc(sizeof (*sep)); 1234 if (sep == NULL) { 1235 syslog(LOG_ERR, "Out of memory."); 1236 exit(1); 1237 } 1238 *sep = *cp; 1239 sep->se_fd = -1; 1240 sep->se_rpcprog = -1; 1241 sep->se_next = servtab; 1242 servtab = sep; 1243 return (sep); 1244 } 1245 1246 FILE *fconfig = NULL; 1247 struct servtab serv; 1248 char line[LINE_MAX]; 1249 char *defhost; 1250 #ifdef IPSEC 1251 static char *policy = NULL; 1252 #endif 1253 1254 static int 1255 setconfig(void) 1256 { 1257 if (defhost) 1258 free(defhost); 1259 defhost = newstr("*"); 1260 #ifdef IPSEC 1261 if (policy) 1262 free(policy); 1263 policy = NULL; 1264 #endif 1265 if (fconfig != NULL) { 1266 fseek(fconfig, 0L, SEEK_SET); 1267 return (1); 1268 } 1269 fconfig = fopen(CONFIG, "r"); 1270 return (fconfig != NULL); 1271 } 1272 1273 static void 1274 endconfig(void) 1275 { 1276 if (fconfig != NULL) { 1277 (void) fclose(fconfig); 1278 fconfig = NULL; 1279 } 1280 if (defhost != NULL) { 1281 free(defhost); 1282 defhost = NULL; 1283 } 1284 } 1285 1286 static struct servtab * 1287 getconfigent(void) 1288 { 1289 struct servtab *sep = &serv; 1290 int argc, val; 1291 char *cp, *cp0, *arg, *buf0, *buf1, *sz0, *sz1; 1292 static char TCPMUX_TOKEN[] = "tcpmux/"; 1293 #define MUX_LEN (sizeof(TCPMUX_TOKEN)-1) 1294 char *hostdelim; 1295 1296 more: 1297 while ((cp = nextline(fconfig))) { 1298 #ifdef IPSEC 1299 /* lines starting with #@ is not a comment, but the policy */ 1300 if (cp[0] == '#' && cp[1] == '@') { 1301 char *p; 1302 for (p = cp + 2; p && *p && isspace((unsigned char)*p); p++) 1303 ; 1304 if (*p == '\0') { 1305 if (policy) 1306 free(policy); 1307 policy = NULL; 1308 } else { 1309 if (ipsecsetup_test(p) < 0) { 1310 syslog(LOG_ERR, 1311 "%s: invalid ipsec policy \"%s\"", 1312 CONFIG, p); 1313 exit(1); 1314 } else { 1315 if (policy) 1316 free(policy); 1317 policy = newstr(p); 1318 } 1319 } 1320 } 1321 #endif 1322 if (*cp == '#' || *cp == '\0') 1323 continue; 1324 #ifdef MULOG 1325 /* Avoid use of `skip' if there is a danger of it looking 1326 * at continuation lines. 1327 */ 1328 do { 1329 cp++; 1330 } while (*cp == ' ' || *cp == '\t'); 1331 if (*cp == '\0') 1332 continue; 1333 if ((arg = skip(&cp)) == NULL) 1334 continue; 1335 if (strcmp(arg, "DOMAIN")) 1336 continue; 1337 if (curdom) 1338 free(curdom); 1339 curdom = NULL; 1340 while (*cp == ' ' || *cp == '\t') 1341 cp++; 1342 if (*cp == '\0') 1343 continue; 1344 arg = cp; 1345 while (*cp && *cp != ' ' && *cp != '\t') 1346 cp++; 1347 if (*cp != '\0') 1348 *cp++ = '\0'; 1349 curdom = newstr(arg); 1350 #endif 1351 break; 1352 } 1353 if (cp == NULL) 1354 return (NULL); 1355 /* 1356 * clear the static buffer, since some fields (se_ctrladdr, 1357 * for example) don't get initialized here. 1358 */ 1359 memset((caddr_t)sep, 0, sizeof *sep); 1360 arg = skip(&cp); 1361 if (cp == NULL) { 1362 /* got an empty line containing just blanks/tabs. */ 1363 goto more; 1364 } 1365 /* Check for a host name. */ 1366 hostdelim = strrchr(arg, ':'); 1367 if (hostdelim) { 1368 *hostdelim = '\0'; 1369 if (arg[0] == '[' && hostdelim > arg && hostdelim[-1] == ']') { 1370 hostdelim[-1] = '\0'; 1371 sep->se_hostaddr = newstr(arg + 1); 1372 } else 1373 sep->se_hostaddr = newstr(arg); 1374 arg = hostdelim + 1; 1375 /* 1376 * If the line is of the form `host:', then just change the 1377 * default host for the following lines. 1378 */ 1379 if (*arg == '\0') { 1380 arg = skip(&cp); 1381 if (cp == NULL) { 1382 free(defhost); 1383 defhost = sep->se_hostaddr; 1384 goto more; 1385 } 1386 } 1387 } else 1388 sep->se_hostaddr = newstr(defhost); 1389 if (strncmp(arg, TCPMUX_TOKEN, MUX_LEN) == 0) { 1390 char *c = arg + MUX_LEN; 1391 if (*c == '+') { 1392 sep->se_type = MUXPLUS_TYPE; 1393 c++; 1394 } else 1395 sep->se_type = MUX_TYPE; 1396 sep->se_service = newstr(c); 1397 } else { 1398 sep->se_service = newstr(arg); 1399 sep->se_type = NORM_TYPE; 1400 } 1401 1402 arg = sskip(&cp); 1403 if (strncmp(arg, "stream", sizeof("stream") - 1) == 0) { 1404 char *accf, *accf_arg; 1405 1406 sep->se_socktype = SOCK_STREAM; 1407 1408 /* one and only one accept filter */ 1409 accf = index(arg, ':'); 1410 if (accf) { 1411 if (accf != rindex(arg, ':') || /* more than one */ 1412 *(accf + 1) == '\0') { /* nothing beyond */ 1413 sep->se_socktype = -1; 1414 } else { 1415 accf++; /* skip delimiter */ 1416 strncpy(sep->se_accf.af_name, accf, 1417 sizeof(sep->se_accf.af_name)); 1418 accf_arg = index(accf, ','); 1419 if (accf_arg) { /* zero or one arg, no more */ 1420 if ((rindex(accf, ',') != accf_arg)) { 1421 sep->se_socktype = -1; 1422 } else { 1423 accf_arg++; 1424 strncpy(sep->se_accf.af_arg, 1425 accf_arg, 1426 sizeof(sep->se_accf.af_arg)); 1427 } 1428 } 1429 } 1430 } 1431 } 1432 1433 else if (strcmp(arg, "dgram") == 0) 1434 sep->se_socktype = SOCK_DGRAM; 1435 else if (strcmp(arg, "rdm") == 0) 1436 sep->se_socktype = SOCK_RDM; 1437 else if (strcmp(arg, "seqpacket") == 0) 1438 sep->se_socktype = SOCK_SEQPACKET; 1439 else if (strcmp(arg, "raw") == 0) 1440 sep->se_socktype = SOCK_RAW; 1441 else 1442 sep->se_socktype = -1; 1443 1444 arg = sskip(&cp); 1445 if (sep->se_type == NORM_TYPE && 1446 strncmp(arg, "faith/", strlen("faith/")) == 0) { 1447 arg += strlen("faith/"); 1448 sep->se_type = FAITH_TYPE; 1449 } 1450 sep->se_proto = newstr(arg); 1451 1452 #define MALFORMED(arg) \ 1453 do { \ 1454 syslog(LOG_ERR, "%s: malformed buffer size option `%s'", \ 1455 sep->se_service, (arg)); \ 1456 goto more; \ 1457 } while (0) 1458 1459 #define GETVAL(arg) \ 1460 do { \ 1461 if (!isdigit((unsigned char)*(arg))) \ 1462 MALFORMED(arg); \ 1463 val = strtol((arg), &cp0, 10); \ 1464 if (cp0 != NULL) { \ 1465 if (cp0[1] != '\0') \ 1466 MALFORMED((arg)); \ 1467 if (cp0[0] == 'k') \ 1468 val *= 1024; \ 1469 if (cp0[0] == 'm') \ 1470 val *= 1024 * 1024; \ 1471 } \ 1472 if (val < 1) { \ 1473 syslog(LOG_ERR, "%s: invalid buffer size `%s'", \ 1474 sep->se_service, (arg)); \ 1475 goto more; \ 1476 } \ 1477 } while (0) 1478 1479 #define ASSIGN(arg) \ 1480 do { \ 1481 if (strcmp((arg), "sndbuf") == 0) \ 1482 sep->se_sndbuf = val; \ 1483 else if (strcmp((arg), "rcvbuf") == 0) \ 1484 sep->se_rcvbuf = val; \ 1485 else \ 1486 MALFORMED((arg)); \ 1487 } while (0) 1488 1489 /* 1490 * Extract the send and receive buffer sizes before parsing 1491 * the protocol. 1492 */ 1493 sep->se_sndbuf = sep->se_rcvbuf = 0; 1494 buf0 = buf1 = sz0 = sz1 = NULL; 1495 if ((buf0 = strchr(sep->se_proto, ',')) != NULL) { 1496 /* Not meaningful for Tcpmux services. */ 1497 if (ISMUX(sep)) { 1498 syslog(LOG_ERR, "%s: can't specify buffer sizes for " 1499 "tcpmux services", sep->se_service); 1500 goto more; 1501 } 1502 1503 /* Skip the , */ 1504 *buf0++ = '\0'; 1505 1506 /* Check to see if another socket buffer size was specified. */ 1507 if ((buf1 = strchr(buf0, ',')) != NULL) { 1508 /* Skip the , */ 1509 *buf1++ = '\0'; 1510 1511 /* Make sure a 3rd one wasn't specified. */ 1512 if (strchr(buf1, ',') != NULL) { 1513 syslog(LOG_ERR, "%s: too many buffer sizes", 1514 sep->se_service); 1515 goto more; 1516 } 1517 1518 /* Locate the size. */ 1519 if ((sz1 = strchr(buf1, '=')) == NULL) 1520 MALFORMED(buf1); 1521 1522 /* Skip the = */ 1523 *sz1++ = '\0'; 1524 } 1525 1526 /* Locate the size. */ 1527 if ((sz0 = strchr(buf0, '=')) == NULL) 1528 MALFORMED(buf0); 1529 1530 /* Skip the = */ 1531 *sz0++ = '\0'; 1532 1533 GETVAL(sz0); 1534 ASSIGN(buf0); 1535 1536 if (buf1 != NULL) { 1537 GETVAL(sz1); 1538 ASSIGN(buf1); 1539 } 1540 } 1541 1542 #undef ASSIGN 1543 #undef GETVAL 1544 #undef MALFORMED 1545 1546 if (strcmp(sep->se_proto, "unix") == 0) { 1547 sep->se_family = AF_LOCAL; 1548 } else { 1549 val = strlen(sep->se_proto); 1550 if (!val) { 1551 syslog(LOG_ERR, "%s: invalid protocol specified", 1552 sep->se_service); 1553 goto more; 1554 } 1555 val = sep->se_proto[val - 1]; 1556 switch (val) { 1557 case '4': /*tcp4 or udp4*/ 1558 sep->se_family = AF_INET; 1559 break; 1560 #ifdef INET6 1561 case '6': /*tcp6 or udp6*/ 1562 sep->se_family = AF_INET6; 1563 break; 1564 #endif 1565 default: 1566 sep->se_family = AF_INET; /*will become AF_INET6*/ 1567 break; 1568 } 1569 if (strncmp(sep->se_proto, "rpc/", 4) == 0) { 1570 #ifdef RPC 1571 char *cp, *ccp; 1572 cp = strchr(sep->se_service, '/'); 1573 if (cp == 0) { 1574 syslog(LOG_ERR, "%s: no rpc version", 1575 sep->se_service); 1576 goto more; 1577 } 1578 *cp++ = '\0'; 1579 sep->se_rpcversl = sep->se_rpcversh = 1580 strtol(cp, &ccp, 0); 1581 if (ccp == cp) { 1582 badafterall: 1583 syslog(LOG_ERR, "%s/%s: bad rpc version", 1584 sep->se_service, cp); 1585 goto more; 1586 } 1587 if (*ccp == '-') { 1588 cp = ccp + 1; 1589 sep->se_rpcversh = strtol(cp, &ccp, 0); 1590 if (ccp == cp) 1591 goto badafterall; 1592 } 1593 #else 1594 syslog(LOG_ERR, "%s: rpc services not suported", 1595 sep->se_service); 1596 goto more; 1597 #endif /* RPC */ 1598 } 1599 } 1600 arg = sskip(&cp); 1601 { 1602 char *cp; 1603 if ((cp = strchr(arg, ':')) == NULL) 1604 cp = strchr(arg, '.'); 1605 if (cp != NULL) { 1606 *cp++ = '\0'; 1607 sep->se_max = atoi(cp); 1608 } else 1609 sep->se_max = TOOMANY; 1610 } 1611 sep->se_wait = strcmp(arg, "wait") == 0; 1612 if (ISMUX(sep)) { 1613 /* 1614 * Silently enforce "nowait" for TCPMUX services since 1615 * they don't have an assigned port to listen on. 1616 */ 1617 sep->se_wait = 0; 1618 1619 if (strncmp(sep->se_proto, "tcp", 3)) { 1620 syslog(LOG_ERR, 1621 "%s: bad protocol for tcpmux service %s", 1622 CONFIG, sep->se_service); 1623 goto more; 1624 } 1625 if (sep->se_socktype != SOCK_STREAM) { 1626 syslog(LOG_ERR, 1627 "%s: bad socket type for tcpmux service %s", 1628 CONFIG, sep->se_service); 1629 goto more; 1630 } 1631 } 1632 sep->se_user = newstr(sskip(&cp)); 1633 if ((sep->se_group = strchr(sep->se_user, ':')) != NULL) 1634 *sep->se_group++ = '\0'; 1635 else if ((sep->se_group = strchr(sep->se_user, '.')) != NULL) 1636 *sep->se_group++ = '\0'; 1637 1638 sep->se_server = newstr(sskip(&cp)); 1639 if (strcmp(sep->se_server, "internal") == 0) { 1640 struct biltin *bi; 1641 1642 for (bi = biltins; bi->bi_service; bi++) 1643 if (bi->bi_socktype == sep->se_socktype && 1644 strcmp(bi->bi_service, sep->se_service) == 0) 1645 break; 1646 if (bi->bi_service == 0) { 1647 syslog(LOG_ERR, "internal service %s unknown", 1648 sep->se_service); 1649 goto more; 1650 } 1651 sep->se_bi = bi; 1652 sep->se_wait = bi->bi_wait; 1653 } else 1654 sep->se_bi = NULL; 1655 argc = 0; 1656 for (arg = skip(&cp); cp; arg = skip(&cp)) { 1657 #if MULOG 1658 char *colon; 1659 1660 if (argc == 0 && (colon = strrchr(arg, ':'))) { 1661 while (arg < colon) { 1662 int x; 1663 char *ccp; 1664 1665 switch (*arg++) { 1666 case 'l': 1667 x = 1; 1668 if (isdigit(*arg)) { 1669 x = strtol(arg, &ccp, 0); 1670 if (ccp == arg) 1671 break; 1672 arg = ccp; 1673 } 1674 sep->se_log &= ~MULOG_RFC931; 1675 sep->se_log |= x; 1676 break; 1677 case 'a': 1678 sep->se_log |= MULOG_RFC931; 1679 break; 1680 default: 1681 break; 1682 } 1683 } 1684 arg = colon + 1; 1685 } 1686 #endif 1687 if (argc < MAXARGV) 1688 sep->se_argv[argc++] = newstr(arg); 1689 } 1690 while (argc <= MAXARGV) 1691 sep->se_argv[argc++] = NULL; 1692 #ifdef IPSEC 1693 sep->se_policy = policy ? newstr(policy) : NULL; 1694 #endif 1695 return (sep); 1696 } 1697 1698 static void 1699 freeconfig(struct servtab *cp) 1700 { 1701 int i; 1702 1703 if (cp->se_hostaddr) 1704 free(cp->se_hostaddr); 1705 if (cp->se_service) 1706 free(cp->se_service); 1707 if (cp->se_proto) 1708 free(cp->se_proto); 1709 if (cp->se_user) 1710 free(cp->se_user); 1711 /* Note: se_group is part of the newstr'ed se_user */ 1712 if (cp->se_server) 1713 free(cp->se_server); 1714 for (i = 0; i < MAXARGV; i++) 1715 if (cp->se_argv[i]) 1716 free(cp->se_argv[i]); 1717 #ifdef IPSEC 1718 if (cp->se_policy) 1719 free(cp->se_policy); 1720 #endif 1721 } 1722 1723 1724 /* 1725 * Safe skip - if skip returns null, log a syntax error in the 1726 * configuration file and exit. 1727 */ 1728 static char * 1729 sskip(char **cpp) 1730 { 1731 char *cp; 1732 1733 cp = skip(cpp); 1734 if (cp == NULL) { 1735 syslog(LOG_ERR, "%s: syntax error", CONFIG); 1736 exit(1); 1737 } 1738 return (cp); 1739 } 1740 1741 static char * 1742 skip(char **cpp) 1743 { 1744 char *cp = *cpp; 1745 char *start; 1746 char quote; 1747 1748 if (*cpp == NULL) 1749 return (NULL); 1750 1751 again: 1752 while (*cp == ' ' || *cp == '\t') 1753 cp++; 1754 if (*cp == '\0') { 1755 int c; 1756 1757 c = getc(fconfig); 1758 (void) ungetc(c, fconfig); 1759 if (c == ' ' || c == '\t') 1760 if ((cp = nextline(fconfig))) 1761 goto again; 1762 *cpp = NULL; 1763 return (NULL); 1764 } 1765 start = cp; 1766 quote = '\0'; 1767 while (*cp && (quote || (*cp != ' ' && *cp != '\t'))) { 1768 if (*cp == '\'' || *cp == '"') { 1769 if (quote && *cp != quote) 1770 cp++; 1771 else { 1772 if (quote) 1773 quote = '\0'; 1774 else 1775 quote = *cp; 1776 memmove(cp, cp+1, strlen(cp)); 1777 } 1778 } else 1779 cp++; 1780 } 1781 if (*cp != '\0') 1782 *cp++ = '\0'; 1783 *cpp = cp; 1784 return (start); 1785 } 1786 1787 static char * 1788 nextline(FILE *fd) 1789 { 1790 char *cp; 1791 1792 if (fgets(line, sizeof (line), fd) == NULL) 1793 return (NULL); 1794 cp = strchr(line, '\n'); 1795 if (cp) 1796 *cp = '\0'; 1797 return (line); 1798 } 1799 1800 static char * 1801 newstr(char *cp) 1802 { 1803 if ((cp = strdup((cp != NULL) ? cp : "")) != NULL) 1804 return (cp); 1805 syslog(LOG_ERR, "strdup: %m"); 1806 exit(1); 1807 } 1808 1809 static void 1810 inetd_setproctitle(char *a, int s) 1811 { 1812 socklen_t size; 1813 struct sockaddr_storage ss; 1814 char hbuf[NI_MAXHOST], *hp; 1815 1816 size = sizeof(ss); 1817 if (getpeername(s, (struct sockaddr *)&ss, &size) == 0) { 1818 if (getnameinfo((struct sockaddr *)&ss, size, hp = hbuf, 1819 sizeof(hbuf), NULL, 0, niflags) != 0) 1820 hp = "?"; 1821 setproctitle("-%s [%s]", a, hp); 1822 } else 1823 setproctitle("-%s", a); 1824 } 1825 1826 static void 1827 bump_nofile(void) 1828 { 1829 #ifdef RLIMIT_NOFILE 1830 1831 #define FD_CHUNK 32 1832 1833 struct rlimit rl; 1834 1835 if (getrlimit(RLIMIT_NOFILE, &rl) < 0) { 1836 syslog(LOG_ERR, "getrlimit: %m"); 1837 return; 1838 } 1839 rl.rlim_cur = MIN(rl.rlim_max, rl.rlim_cur + FD_CHUNK); 1840 if (rl.rlim_cur <= rlim_ofile_cur) { 1841 syslog(LOG_ERR, 1842 "bump_nofile: cannot extend file limit, max = %d", 1843 (int)rl.rlim_cur); 1844 return; 1845 } 1846 1847 if (setrlimit(RLIMIT_NOFILE, &rl) < 0) { 1848 syslog(LOG_ERR, "setrlimit: %m"); 1849 return; 1850 } 1851 1852 rlim_ofile_cur = rl.rlim_cur; 1853 return; 1854 1855 #else 1856 syslog(LOG_ERR, "bump_nofile: cannot extend file limit"); 1857 return; 1858 #endif 1859 } 1860 1861 /* 1862 * Internet services provided internally by inetd: 1863 */ 1864 #define BUFSIZE 4096 1865 1866 /* ARGSUSED */ 1867 static void 1868 echo_stream(int s, struct servtab *sep) /* Echo service -- echo data back */ 1869 { 1870 char buffer[BUFSIZE]; 1871 int i; 1872 1873 inetd_setproctitle(sep->se_service, s); 1874 while ((i = read(s, buffer, sizeof(buffer))) > 0 && 1875 write(s, buffer, i) > 0) 1876 ; 1877 } 1878 1879 /* ARGSUSED */ 1880 static void 1881 echo_dg(int s, struct servtab *sep) /* Echo service -- echo data back */ 1882 { 1883 char buffer[BUFSIZE]; 1884 int i; 1885 socklen_t size; 1886 struct sockaddr_storage ss; 1887 struct sockaddr *sa; 1888 1889 sa = (struct sockaddr *)&ss; 1890 size = sizeof(ss); 1891 if ((i = recvfrom(s, buffer, sizeof(buffer), 0, sa, &size)) < 0) 1892 return; 1893 if (port_good_dg(sa)) 1894 (void) sendto(s, buffer, i, 0, sa, size); 1895 } 1896 1897 /* ARGSUSED */ 1898 static void 1899 discard_stream(int s, struct servtab *sep) /* Discard service -- ignore data */ 1900 { 1901 char buffer[BUFSIZE]; 1902 1903 inetd_setproctitle(sep->se_service, s); 1904 while ((errno = 0, read(s, buffer, sizeof(buffer)) > 0) || 1905 errno == EINTR) 1906 ; 1907 } 1908 1909 /* ARGSUSED */ 1910 static void 1911 discard_dg(int s, struct servtab *sep) /* Discard service -- ignore data */ 1912 1913 { 1914 char buffer[BUFSIZE]; 1915 1916 (void) read(s, buffer, sizeof(buffer)); 1917 } 1918 1919 #define LINESIZ 72 1920 char ring[128]; 1921 char *endring; 1922 1923 static void 1924 initring(void) 1925 { 1926 int i; 1927 1928 endring = ring; 1929 1930 for (i = 0; i <= 128; ++i) 1931 if (isprint(i)) 1932 *endring++ = i; 1933 } 1934 1935 /* ARGSUSED */ 1936 static void 1937 chargen_stream(int s,struct servtab *sep) /* Character generator */ 1938 { 1939 int len; 1940 char *rs, text[LINESIZ+2]; 1941 1942 inetd_setproctitle(sep->se_service, s); 1943 1944 if (!endring) { 1945 initring(); 1946 rs = ring; 1947 } 1948 1949 text[LINESIZ] = '\r'; 1950 text[LINESIZ + 1] = '\n'; 1951 for (rs = ring;;) { 1952 if ((len = endring - rs) >= LINESIZ) 1953 memmove(text, rs, LINESIZ); 1954 else { 1955 memmove(text, rs, len); 1956 memmove(text + len, ring, LINESIZ - len); 1957 } 1958 if (++rs == endring) 1959 rs = ring; 1960 if (write(s, text, sizeof(text)) != sizeof(text)) 1961 break; 1962 } 1963 } 1964 1965 /* ARGSUSED */ 1966 static void 1967 chargen_dg(int s, struct servtab *sep) /* Character generator */ 1968 { 1969 struct sockaddr_storage ss; 1970 struct sockaddr *sa; 1971 static char *rs; 1972 int len; 1973 socklen_t size; 1974 char text[LINESIZ+2]; 1975 1976 if (endring == 0) { 1977 initring(); 1978 rs = ring; 1979 } 1980 1981 sa = (struct sockaddr *)&ss; 1982 size = sizeof(ss); 1983 if (recvfrom(s, text, sizeof(text), 0, sa, &size) < 0) 1984 return; 1985 1986 if (!port_good_dg(sa)) 1987 return; 1988 1989 if ((len = endring - rs) >= LINESIZ) 1990 memmove(text, rs, LINESIZ); 1991 else { 1992 memmove(text, rs, len); 1993 memmove(text + len, ring, LINESIZ - len); 1994 } 1995 if (++rs == endring) 1996 rs = ring; 1997 text[LINESIZ] = '\r'; 1998 text[LINESIZ + 1] = '\n'; 1999 (void) sendto(s, text, sizeof(text), 0, sa, size); 2000 } 2001 2002 /* 2003 * Return a machine readable date and time, in the form of the 2004 * number of seconds since midnight, Jan 1, 1900. Since gettimeofday 2005 * returns the number of seconds since midnight, Jan 1, 1970, 2006 * we must add 2208988800 seconds to this figure to make up for 2007 * some seventy years Bell Labs was asleep. 2008 */ 2009 2010 static uint32_t 2011 machtime(void) 2012 { 2013 struct timeval tv; 2014 2015 if (gettimeofday(&tv, NULL) < 0) { 2016 if (debug) 2017 fprintf(stderr, "Unable to get time of day\n"); 2018 return (0); 2019 } 2020 #define OFFSET ((uint32_t)25567 * 24*60*60) 2021 return (htonl((uint32_t)(tv.tv_sec + OFFSET))); 2022 #undef OFFSET 2023 } 2024 2025 /* ARGSUSED */ 2026 static void 2027 machtime_stream(int s, struct servtab *sep) 2028 { 2029 uint32_t result; 2030 2031 result = machtime(); 2032 (void) write(s, (char *) &result, sizeof(result)); 2033 } 2034 2035 /* ARGSUSED */ 2036 void 2037 machtime_dg(int s, struct servtab *sep) 2038 { 2039 uint32_t result; 2040 struct sockaddr_storage ss; 2041 struct sockaddr *sa; 2042 socklen_t size; 2043 2044 sa = (struct sockaddr *)&ss; 2045 size = sizeof(ss); 2046 if (recvfrom(s, (char *)&result, sizeof(result), 0, sa, &size) < 0) 2047 return; 2048 if (!port_good_dg(sa)) 2049 return; 2050 result = machtime(); 2051 (void) sendto(s, (char *) &result, sizeof(result), 0, sa, size); 2052 } 2053 2054 /* ARGSUSED */ 2055 static void 2056 daytime_stream(int s,struct servtab *sep) 2057 /* Return human-readable time of day */ 2058 { 2059 char buffer[256]; 2060 time_t clock; 2061 int len; 2062 2063 clock = time((time_t *) 0); 2064 2065 len = snprintf(buffer, sizeof buffer, "%.24s\r\n", ctime(&clock)); 2066 (void) write(s, buffer, len); 2067 } 2068 2069 /* ARGSUSED */ 2070 void 2071 daytime_dg(int s, struct servtab *sep) 2072 /* Return human-readable time of day */ 2073 { 2074 char buffer[256]; 2075 time_t clock; 2076 struct sockaddr_storage ss; 2077 struct sockaddr *sa; 2078 socklen_t size; 2079 int len; 2080 2081 clock = time((time_t *) 0); 2082 2083 sa = (struct sockaddr *)&ss; 2084 size = sizeof(ss); 2085 if (recvfrom(s, buffer, sizeof(buffer), 0, sa, &size) < 0) 2086 return; 2087 if (!port_good_dg(sa)) 2088 return; 2089 len = snprintf(buffer, sizeof buffer, "%.24s\r\n", ctime(&clock)); 2090 (void) sendto(s, buffer, len, 0, sa, size); 2091 } 2092 2093 /* 2094 * print_service: 2095 * Dump relevant information to stderr 2096 */ 2097 static void 2098 print_service(char *action, struct servtab *sep) 2099 { 2100 2101 if (isrpcservice(sep)) 2102 fprintf(stderr, 2103 "%s: %s rpcprog=%d, rpcvers = %d/%d, proto=%s, wait.max=%d.%d, user:group=%s:%s builtin=%lx server=%s" 2104 #ifdef IPSEC 2105 " policy=\"%s\"" 2106 #endif 2107 "\n", 2108 action, sep->se_service, 2109 sep->se_rpcprog, sep->se_rpcversh, sep->se_rpcversl, sep->se_proto, 2110 sep->se_wait, sep->se_max, sep->se_user, sep->se_group, 2111 (long)sep->se_bi, sep->se_server 2112 #ifdef IPSEC 2113 , (sep->se_policy ? sep->se_policy : "") 2114 #endif 2115 ); 2116 else 2117 fprintf(stderr, 2118 "%s: %s proto=%s%s, wait.max=%d.%d, user:group=%s:%s builtin=%lx server=%s" 2119 #ifdef IPSEC 2120 " policy=%s" 2121 #endif 2122 "\n", 2123 action, sep->se_service, 2124 sep->se_type == FAITH_TYPE ? "faith/" : "", 2125 sep->se_proto, 2126 sep->se_wait, sep->se_max, sep->se_user, sep->se_group, 2127 (long)sep->se_bi, sep->se_server 2128 #ifdef IPSEC 2129 , (sep->se_policy ? sep->se_policy : "") 2130 #endif 2131 ); 2132 } 2133 2134 static void 2135 usage(void) 2136 { 2137 #ifdef LIBWRAP 2138 (void)fprintf(stderr, "usage: %s [-dl] [conf]\n", getprogname()); 2139 #else 2140 (void)fprintf(stderr, "usage: %s [-d] [conf]\n", getprogname()); 2141 #endif 2142 exit(1); 2143 } 2144 2145 2146 /* 2147 * Based on TCPMUX.C by Mark K. Lottor November 1988 2148 * sri-nic::ps:<mkl>tcpmux.c 2149 */ 2150 2151 static int /* # of characters upto \r,\n or \0 */ 2152 getline(int fd, char *buf, int len) 2153 { 2154 int count = 0, n; 2155 2156 do { 2157 n = read(fd, buf, len-count); 2158 if (n == 0) 2159 return (count); 2160 if (n < 0) 2161 return (-1); 2162 while (--n >= 0) { 2163 if (*buf == '\r' || *buf == '\n' || *buf == '\0') 2164 return (count); 2165 count++; 2166 buf++; 2167 } 2168 } while (count < len); 2169 return (count); 2170 } 2171 2172 #define MAX_SERV_LEN (256+2) /* 2 bytes for \r\n */ 2173 2174 #define strwrite(fd, buf) (void) write(fd, buf, sizeof(buf)-1) 2175 2176 static void 2177 tcpmux(int ctrl, struct servtab *sep) 2178 { 2179 char service[MAX_SERV_LEN+1]; 2180 int len; 2181 2182 /* Get requested service name */ 2183 if ((len = getline(ctrl, service, MAX_SERV_LEN)) < 0) { 2184 strwrite(ctrl, "-Error reading service name\r\n"); 2185 goto reject; 2186 } 2187 service[len] = '\0'; 2188 2189 if (debug) 2190 fprintf(stderr, "tcpmux: someone wants %s\n", service); 2191 2192 /* 2193 * Help is a required command, and lists available services, 2194 * one per line. 2195 */ 2196 if (!strcasecmp(service, "help")) { 2197 strwrite(ctrl, "+Available services:\r\n"); 2198 strwrite(ctrl, "help\r\n"); 2199 for (sep = servtab; sep != NULL; sep = sep->se_next) { 2200 if (!ISMUX(sep)) 2201 continue; 2202 (void)write(ctrl, sep->se_service, 2203 strlen(sep->se_service)); 2204 strwrite(ctrl, "\r\n"); 2205 } 2206 goto reject; 2207 } 2208 2209 /* Try matching a service in inetd.conf with the request */ 2210 for (sep = servtab; sep != NULL; sep = sep->se_next) { 2211 if (!ISMUX(sep)) 2212 continue; 2213 if (!strcasecmp(service, sep->se_service)) { 2214 if (ISMUXPLUS(sep)) 2215 strwrite(ctrl, "+Go\r\n"); 2216 run_service(ctrl, sep, 1 /* forked */); 2217 return; 2218 } 2219 } 2220 strwrite(ctrl, "-Service not available\r\n"); 2221 reject: 2222 _exit(1); 2223 } 2224 2225 #ifdef MULOG 2226 void 2227 dolog(struct servtab *sep, int ctrl) 2228 { 2229 struct sockaddr_storage ss; 2230 struct sockaddr *sa = (struct sockaddr *)&ss; 2231 socklen_t len = sizeof(ss); 2232 char *host, *dp, buf[BUFSIZ]; 2233 int connected = 1; 2234 2235 switch (sep->se_family) { 2236 case AF_INET: 2237 #ifdef INET6 2238 case AF_INET6: 2239 #endif 2240 break; 2241 default: 2242 return; 2243 } 2244 2245 if (getpeername(ctrl, sa, &len) < 0) { 2246 if (errno != ENOTCONN) { 2247 syslog(LOG_ERR, "getpeername: %m"); 2248 return; 2249 } 2250 if (recvfrom(ctrl, buf, sizeof(buf), MSG_PEEK, sa, &len) < 0) { 2251 syslog(LOG_ERR, "recvfrom: %m"); 2252 return; 2253 } 2254 connected = 0; 2255 } 2256 switch (sa->sa_family) { 2257 case AF_INET: 2258 #ifdef INET6 2259 case AF_INET6: 2260 #endif 2261 break; 2262 default: 2263 syslog(LOG_ERR, "unexpected address family %u", sa->sa_family); 2264 return; 2265 } 2266 2267 if (getnameinfo(sa, len, buf, sizeof(buf), NULL, 0, 0) != 0) 2268 strlcpy(buf, "?", sizeof(buf)); 2269 host = buf; 2270 2271 switch (sep->se_log & ~MULOG_RFC931) { 2272 case 0: 2273 return; 2274 case 1: 2275 if (curdom == NULL || *curdom == '\0') 2276 break; 2277 dp = host + strlen(host) - strlen(curdom); 2278 if (dp < host) 2279 break; 2280 if (debug) 2281 fprintf(stderr, "check \"%s\" against curdom \"%s\"\n", 2282 host, curdom); 2283 if (strcasecmp(dp, curdom) == 0) 2284 return; 2285 break; 2286 case 2: 2287 default: 2288 break; 2289 } 2290 2291 openlog("", LOG_NOWAIT, MULOG); 2292 2293 if (connected && (sep->se_log & MULOG_RFC931)) 2294 syslog(LOG_INFO, "%s@%s wants %s", 2295 rfc931_name(sa, ctrl), host, sep->se_service); 2296 else 2297 syslog(LOG_INFO, "%s wants %s", 2298 host, sep->se_service); 2299 } 2300 2301 /* 2302 * From tcp_log by 2303 * Wietse Venema, Eindhoven University of Technology, The Netherlands. 2304 */ 2305 #if 0 2306 static char sccsid[] = "@(#) rfc931.c 1.3 92/08/31 22:54:46"; 2307 #endif 2308 2309 #include <setjmp.h> 2310 2311 #define RFC931_PORT 113 /* Semi-well-known port */ 2312 #define TIMEOUT 4 2313 #define TIMEOUT2 10 2314 2315 static jmp_buf timebuf; 2316 2317 /* timeout - handle timeouts */ 2318 2319 static void 2320 timeout(int sig) 2321 { 2322 longjmp(timebuf, sig); 2323 } 2324 2325 /* rfc931_name - return remote user name */ 2326 2327 char * 2328 rfc931_name(struct sockaddr *there, /* remote link information */ 2329 int ctrl) 2330 { 2331 struct sockaddr_storage here; /* local link information */ 2332 struct sockaddr_storage sin; /* for talking to RFC931 daemon */ 2333 socklen_t length; 2334 int s; 2335 unsigned remote; 2336 unsigned local; 2337 static char user[256]; /* XXX */ 2338 char buf[256]; 2339 char *cp; 2340 char *result = "USER_UNKNOWN"; 2341 int len; 2342 u_int16_t myport, hisport; 2343 2344 /* Find out local port number of our stdin. */ 2345 2346 length = sizeof(here); 2347 if (getsockname(ctrl, (struct sockaddr *) &here, &length) == -1) { 2348 syslog(LOG_ERR, "getsockname: %m"); 2349 return (result); 2350 } 2351 switch (here.ss_family) { 2352 case AF_INET: 2353 myport = ((struct sockaddr_in *)&here)->sin_port; 2354 break; 2355 #ifdef INET6 2356 case AF_INET6: 2357 myport = ((struct sockaddr_in6 *)&here)->sin6_port; 2358 break; 2359 #endif 2360 } 2361 switch (there->sa_family) { 2362 case AF_INET: 2363 hisport = ((struct sockaddr_in *)&there)->sin_port; 2364 break; 2365 #ifdef INET6 2366 case AF_INET6: 2367 hisport = ((struct sockaddr_in6 *)&there)->sin6_port; 2368 break; 2369 #endif 2370 } 2371 /* Set up timer so we won't get stuck. */ 2372 2373 if ((s = socket(here.ss_family, SOCK_STREAM, 0)) == -1) { 2374 syslog(LOG_ERR, "socket: %m"); 2375 return (result); 2376 } 2377 2378 sin = here; 2379 switch (sin.ss_family) { 2380 case AF_INET: 2381 ((struct sockaddr_in *)&sin)->sin_port = htons(0); 2382 break; 2383 #ifdef INET6 2384 case AF_INET6: 2385 ((struct sockaddr_in6 *)&sin)->sin6_port = htons(0); 2386 break; 2387 #endif 2388 } 2389 if (bind(s, (struct sockaddr *) &sin, sin.ss_len) == -1) { 2390 syslog(LOG_ERR, "bind: %m"); 2391 return (result); 2392 } 2393 2394 signal(SIGALRM, timeout); 2395 if (setjmp(timebuf)) { 2396 close(s); /* not: fclose(fp) */ 2397 return (result); 2398 } 2399 alarm(TIMEOUT); 2400 2401 /* Connect to the RFC931 daemon. */ 2402 2403 memcpy(&sin, there, there->sa_len); 2404 switch (sin.ss_family) { 2405 case AF_INET: 2406 ((struct sockaddr_in *)&sin)->sin_port = htons(RFC931_PORT); 2407 break; 2408 #ifdef INET6 2409 case AF_INET6: 2410 ((struct sockaddr_in6 *)&sin)->sin6_port = htons(RFC931_PORT); 2411 break; 2412 #endif 2413 } 2414 if (connect(s, (struct sockaddr *) &sin, sin.ss_len) == -1) { 2415 close(s); 2416 alarm(0); 2417 return (result); 2418 } 2419 2420 /* Query the RFC 931 server. Would 13-byte writes ever be broken up? */ 2421 (void)snprintf(buf, sizeof buf, "%u,%u\r\n", ntohs(hisport), 2422 ntohs(myport)); 2423 2424 for (len = 0, cp = buf; len < strlen(buf); ) { 2425 int n; 2426 2427 if ((n = write(s, cp, strlen(buf) - len)) == -1) { 2428 close(s); 2429 alarm(0); 2430 return (result); 2431 } 2432 cp += n; 2433 len += n; 2434 } 2435 2436 /* Read response */ 2437 for (cp = buf; cp < buf + sizeof(buf) - 1; ) { 2438 char c; 2439 if (read(s, &c, 1) != 1) { 2440 close(s); 2441 alarm(0); 2442 return (result); 2443 } 2444 if (c == '\n') 2445 break; 2446 *cp++ = c; 2447 } 2448 *cp = '\0'; 2449 2450 if (sscanf(buf, "%u , %u : USERID :%*[^:]:%255s", &remote, &local, 2451 user) == 3 && ntohs(hisport) == remote && ntohs(myport) == local) { 2452 /* Strip trailing carriage return. */ 2453 if ((cp = strchr(user, '\r')) != NULL) 2454 *cp = 0; 2455 result = user; 2456 } 2457 2458 alarm(0); 2459 close(s); 2460 return (result); 2461 } 2462 #endif 2463 2464 /* 2465 * check if the address/port where send data to is one of the obvious ports 2466 * that are used for denial of service attacks like two echo ports 2467 * just echoing data between them 2468 */ 2469 static int 2470 port_good_dg(struct sockaddr *sa) 2471 { 2472 struct in_addr in; 2473 #ifdef INET6 2474 struct in6_addr *in6; 2475 #endif 2476 u_int16_t port; 2477 int i, bad; 2478 char hbuf[NI_MAXHOST]; 2479 2480 bad = 0; 2481 2482 switch (sa->sa_family) { 2483 case AF_INET: 2484 in.s_addr = ntohl(((struct sockaddr_in *)sa)->sin_addr.s_addr); 2485 port = ntohs(((struct sockaddr_in *)sa)->sin_port); 2486 #ifdef INET6 2487 v4chk: 2488 #endif 2489 if (IN_MULTICAST(in.s_addr)) 2490 goto bad; 2491 switch ((in.s_addr & 0xff000000) >> 24) { 2492 case 0: case 127: case 255: 2493 goto bad; 2494 } 2495 if (dg_broadcast(&in)) 2496 goto bad; 2497 break; 2498 #ifdef INET6 2499 case AF_INET6: 2500 in6 = &((struct sockaddr_in6 *)sa)->sin6_addr; 2501 port = ntohs(((struct sockaddr_in6 *)sa)->sin6_port); 2502 if (IN6_IS_ADDR_MULTICAST(in6) || IN6_IS_ADDR_UNSPECIFIED(in6)) 2503 goto bad; 2504 if (IN6_IS_ADDR_V4MAPPED(in6) || IN6_IS_ADDR_V4COMPAT(in6)) { 2505 memcpy(&in, &in6->s6_addr[12], sizeof(in)); 2506 in.s_addr = ntohl(in.s_addr); 2507 goto v4chk; 2508 } 2509 break; 2510 #endif 2511 default: 2512 /* XXX unsupported af, is it safe to assume it to be safe? */ 2513 return (1); 2514 } 2515 2516 for (i = 0; bad_ports[i] != 0; i++) { 2517 if (port == bad_ports[i]) 2518 goto bad; 2519 } 2520 2521 return (1); 2522 2523 bad: 2524 if (getnameinfo(sa, sa->sa_len, hbuf, sizeof(hbuf), NULL, 0, 2525 niflags) != 0) 2526 strlcpy(hbuf, "?", sizeof(hbuf)); 2527 syslog(LOG_WARNING,"Possible DoS attack from %s, Port %d", 2528 hbuf, port); 2529 return (0); 2530 } 2531 2532 /* XXX need optimization */ 2533 static int 2534 dg_broadcast(struct in_addr *in) 2535 { 2536 struct ifaddrs *ifa, *ifap; 2537 struct sockaddr_in *sin; 2538 2539 if (getifaddrs(&ifap) < 0) 2540 return (0); 2541 for (ifa = ifap; ifa; ifa = ifa->ifa_next) { 2542 if (ifa->ifa_addr->sa_family != AF_INET || 2543 (ifa->ifa_flags & IFF_BROADCAST) == 0) 2544 continue; 2545 sin = (struct sockaddr_in *)ifa->ifa_broadaddr; 2546 if (sin->sin_addr.s_addr == in->s_addr) { 2547 freeifaddrs(ifap); 2548 return (1); 2549 } 2550 } 2551 freeifaddrs(ifap); 2552 return (0); 2553 } 2554 2555 static int 2556 my_kevent(const struct kevent *changelist, size_t nchanges, 2557 struct kevent *eventlist, size_t nevents) 2558 { 2559 int result; 2560 2561 while ((result = kevent(kq, changelist, nchanges, eventlist, nevents, 2562 NULL)) < 0) 2563 if (errno != EINTR) { 2564 syslog(LOG_ERR, "kevent: %m"); 2565 exit(EXIT_FAILURE); 2566 } 2567 2568 return (result); 2569 } 2570 2571 static struct kevent * 2572 allocchange(void) 2573 { 2574 if (changes == A_CNT(changebuf)) { 2575 (void) my_kevent(changebuf, A_CNT(changebuf), NULL, 0); 2576 changes = 0; 2577 } 2578 2579 return (&changebuf[changes++]); 2580 } 2581
Indexes created Thu Sep 25 16:09:42 GMT 2025