inetd.c revision 1.51
1/* $NetBSD: inetd.c,v 1.51 1999/07/19 15:49:39 ghudson Exp $ */ 2 3/*- 4 * Copyright (c) 1998 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. 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 * 3. All advertising materials mentioning features or use of this software 20 * must display the following acknowledgement: 21 * This product includes software developed by the NetBSD 22 * Foundation, Inc. and its contributors. 23 * 4. Neither the name of The NetBSD Foundation nor the names of its 24 * contributors may be used to endorse or promote products derived 25 * from this software without specific prior written permission. 26 * 27 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 28 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 29 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 30 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 31 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 32 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 33 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 34 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 35 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 36 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 37 * POSSIBILITY OF SUCH DAMAGE. 38 */ 39 40/* 41 * Copyright (c) 1983, 1991, 1993, 1994 42 * The Regents of the University of California. All rights reserved. 43 * 44 * Redistribution and use in source and binary forms, with or without 45 * modification, are permitted provided that the following conditions 46 * are met: 47 * 1. Redistributions of source code must retain the above copyright 48 * notice, this list of conditions and the following disclaimer. 49 * 2. Redistributions in binary form must reproduce the above copyright 50 * notice, this list of conditions and the following disclaimer in the 51 * documentation and/or other materials provided with the distribution. 52 * 3. All advertising materials mentioning features or use of this software 53 * must display the following acknowledgement: 54 * This product includes software developed by the University of 55 * California, Berkeley and its contributors. 56 * 4. Neither the name of the University nor the names of its contributors 57 * may be used to endorse or promote products derived from this software 58 * without specific prior written permission. 59 * 60 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 61 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 62 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 63 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 64 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 65 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 66 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 67 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 68 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 69 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 70 * SUCH DAMAGE. 71 */ 72 73#include <sys/cdefs.h> 74#ifndef lint 75__COPYRIGHT("@(#) Copyright (c) 1983, 1991, 1993, 1994\n\ 76 The Regents of the University of California. All rights reserved.\n"); 77#if 0 78static char sccsid[] = "@(#)inetd.c 8.4 (Berkeley) 4/13/94"; 79#else 80__RCSID("$NetBSD: inetd.c,v 1.51 1999/07/19 15:49:39 ghudson Exp $"); 81#endif 82#endif /* not lint */ 83 84/* 85 * Inetd - Internet super-server 86 * 87 * This program invokes all internet services as needed. Connection-oriented 88 * services are invoked each time a connection is made, by creating a process. 89 * This process is passed the connection as file descriptor 0 and is expected 90 * to do a getpeername to find out the source host and port. 91 * 92 * Datagram oriented services are invoked when a datagram 93 * arrives; a process is created and passed a pending message 94 * on file descriptor 0. Datagram servers may either connect 95 * to their peer, freeing up the original socket for inetd 96 * to receive further messages on, or ``take over the socket'', 97 * processing all arriving datagrams and, eventually, timing 98 * out. The first type of server is said to be ``multi-threaded''; 99 * the second type of server ``single-threaded''. 100 * 101 * Inetd uses a configuration file which is read at startup 102 * and, possibly, at some later time in response to a hangup signal. 103 * The configuration file is ``free format'' with fields given in the 104 * order shown below. Continuation lines for an entry must being with 105 * a space or tab. All fields must be present in each entry. 106 * 107 * service name must be in /etc/services or must 108 * name a tcpmux service 109 * socket type stream/dgram/raw/rdm/seqpacket 110 * protocol must be in /etc/protocols 111 * wait/nowait[.max] single-threaded/multi-threaded, max # 112 * user[.group] user/group to run daemon as 113 * server program full path name 114 * server program arguments maximum of MAXARGS (20) 115 * 116 * For RPC services 117 * service name/version must be in /etc/rpc 118 * socket type stream/dgram/raw/rdm/seqpacket 119 * protocol must be in /etc/protocols 120 * wait/nowait[.max] single-threaded/multi-threaded 121 * user[.group] user to run daemon as 122 * server program full path name 123 * server program arguments maximum of MAXARGS (20) 124 * 125 * For non-RPC services, the "service name" can be of the form 126 * hostaddress:servicename, in which case the hostaddress is used 127 * as the host portion of the address to listen on. If hostaddress 128 * consists of a single `*' character, INADDR_ANY is used. 129 * 130 * A line can also consist of just 131 * hostaddress: 132 * where hostaddress is as in the preceding paragraph. Such a line must 133 * have no further fields; the specified hostaddress is remembered and 134 * used for all further lines that have no hostaddress specified, 135 * until the next such line (or EOF). (This is why * is provided to 136 * allow explicit specification of INADDR_ANY.) A line 137 * *: 138 * is implicitly in effect at the beginning of the file. 139 * 140 * The hostaddress specifier may (and often will) contain dots; 141 * the service name must not. 142 * 143 * For RPC services, host-address specifiers are accepted and will 144 * work to some extent; however, because of limitations in the 145 * portmapper interface, it will not work to try to give more than 146 * one line for any given RPC service, even if the host-address 147 * specifiers are different. 148 * 149 * TCP services without official port numbers are handled with the 150 * RFC1078-based tcpmux internal service. Tcpmux listens on port 1 for 151 * requests. When a connection is made from a foreign host, the service 152 * requested is passed to tcpmux, which looks it up in the servtab list 153 * and returns the proper entry for the service. Tcpmux returns a 154 * negative reply if the service doesn't exist, otherwise the invoked 155 * server is expected to return the positive reply if the service type in 156 * inetd.conf file has the prefix "tcpmux/". If the service type has the 157 * prefix "tcpmux/+", tcpmux will return the positive reply for the 158 * process; this is for compatibility with older server code, and also 159 * allows you to invoke programs that use stdin/stdout without putting any 160 * special server code in them. Services that use tcpmux are "nowait" 161 * because they do not have a well-known port and hence cannot listen 162 * for new requests. 163 * 164 * Comment lines are indicated by a `#' in column 1. 165 * 166 * #ifdef IPSEC 167 * Comment lines that start with "#@" denote IPsec policy string, as described 168 * in ipsec_set_policy(3). This will affect all the following items in 169 * inetd.conf(8). To reset the policy, just use "#@" line. By default, 170 * there's no IPsec policy. 171 * #endif 172 */ 173 174/* 175 * Here's the scoop concerning the user.group feature: 176 * 177 * 1) set-group-option off. 178 * 179 * a) user = root: NO setuid() or setgid() is done 180 * 181 * b) other: setuid() 182 * setgid(primary group as found in passwd) 183 * initgroups(name, primary group) 184 * 185 * 2) set-group-option on. 186 * 187 * a) user = root: NO setuid() 188 * setgid(specified group) 189 * NO initgroups() 190 * 191 * b) other: setuid() 192 * setgid(specified group) 193 * initgroups(name, specified group) 194 * 195 */ 196 197#include <sys/param.h> 198#include <sys/stat.h> 199#include <sys/ioctl.h> 200#include <sys/socket.h> 201#include <sys/un.h> 202#include <sys/wait.h> 203#include <sys/time.h> 204#include <sys/resource.h> 205 206#ifndef RLIMIT_NOFILE 207#define RLIMIT_NOFILE RLIMIT_OFILE 208#endif 209 210#define RPC 211 212#include <netinet/in.h> 213#include <arpa/inet.h> 214#ifdef RPC 215#include <rpc/rpc.h> 216#include <rpc/pmap_clnt.h> 217#endif 218 219#include <ctype.h> 220#include <errno.h> 221#include <fcntl.h> 222#include <grp.h> 223#include <netdb.h> 224#include <pwd.h> 225#include <signal.h> 226#include <stdio.h> 227#include <stdlib.h> 228#include <string.h> 229#include <syslog.h> 230#include <unistd.h> 231#include <util.h> 232 233#include "pathnames.h" 234 235#ifdef IPSEC 236#include <netinet6/ipsec.h> 237#ifndef IPSEC_POLICY_IPSEC /* no ipsec support on old ipsec */ 238#undef IPSEC 239#endif 240#endif 241 242#ifdef LIBWRAP 243# include <tcpd.h> 244#ifndef LIBWRAP_ALLOW_FACILITY 245# define LIBWRAP_ALLOW_FACILITY LOG_AUTH 246#endif 247#ifndef LIBWRAP_ALLOW_SEVERITY 248# define LIBWRAP_ALLOW_SEVERITY LOG_INFO 249#endif 250#ifndef LIBWRAP_DENY_FACILITY 251# define LIBWRAP_DENY_FACILITY LOG_AUTH 252#endif 253#ifndef LIBWRAP_DENY_SEVERITY 254# define LIBWRAP_DENY_SEVERITY LOG_WARNING 255#endif 256int allow_severity = LIBWRAP_ALLOW_FACILITY|LIBWRAP_ALLOW_SEVERITY; 257int deny_severity = LIBWRAP_DENY_FACILITY|LIBWRAP_DENY_SEVERITY; 258#endif 259 260#define TOOMANY 40 /* don't start more than TOOMANY */ 261#define CNT_INTVL 60 /* servers in CNT_INTVL sec. */ 262#define RETRYTIME (60*10) /* retry after bind or server fail */ 263 264#define SIGBLOCK (sigmask(SIGCHLD)|sigmask(SIGHUP)|sigmask(SIGALRM)) 265 266int debug; 267#ifdef LIBWRAP 268int lflag; 269#endif 270int nsock, maxsock; 271fd_set allsock; 272int options; 273int timingout; 274struct servent *sp; 275char *curdom; 276 277#ifndef OPEN_MAX 278#define OPEN_MAX 64 279#endif 280 281/* Reserve some descriptors, 3 stdio + at least: 1 log, 1 conf. file */ 282#define FD_MARGIN (8) 283typeof(((struct rlimit *)0)->rlim_cur) rlim_ofile_cur = OPEN_MAX; 284 285#ifdef RLIMIT_NOFILE 286struct rlimit rlim_ofile; 287#endif 288 289struct servtab { 290 char *se_hostaddr; /* host address to listen on */ 291 char *se_service; /* name of service */ 292 int se_socktype; /* type of socket to use */ 293 int se_family; /* address family */ 294 char *se_proto; /* protocol used */ 295 int se_sndbuf; /* sndbuf size */ 296 int se_rcvbuf; /* rcvbuf size */ 297 int se_rpcprog; /* rpc program number */ 298 int se_rpcversl; /* rpc program lowest version */ 299 int se_rpcversh; /* rpc program highest version */ 300#define isrpcservice(sep) ((sep)->se_rpcversl != 0) 301 pid_t se_wait; /* single threaded server */ 302 short se_checked; /* looked at during merge */ 303 char *se_user; /* user name to run as */ 304 char *se_group; /* group name to run as */ 305 struct biltin *se_bi; /* if built-in, description */ 306 char *se_server; /* server program */ 307#define MAXARGV 20 308 char *se_argv[MAXARGV+1]; /* program arguments */ 309#ifdef IPSEC 310 char *se_policy; /* IPsec poilcy string */ 311#endif 312 int se_fd; /* open descriptor */ 313 int se_type; /* type */ 314 union { 315 struct sockaddr se_un_ctrladdr; 316 struct sockaddr_in se_un_ctrladdr_in; 317 struct sockaddr_in6 se_un_ctrladdr_in6; 318 struct sockaddr_un se_un_ctrladdr_un; 319 } se_un; /* bound address */ 320#define se_ctrladdr se_un.se_un_ctrladdr 321#define se_ctrladdr_in se_un.se_un_ctrladdr_in 322#define se_ctrladdr_un se_un.se_un_ctrladdr_un 323 int se_ctrladdr_size; 324 int se_max; /* max # of instances of this service */ 325 int se_count; /* number started since se_time */ 326 struct timeval se_time; /* start of se_count */ 327#ifdef MULOG 328 int se_log; 329#define MULOG_RFC931 0x40000000 330#endif 331 struct servtab *se_next; 332} *servtab; 333 334#define NORM_TYPE 0 335#define MUX_TYPE 1 336#define MUXPLUS_TYPE 2 337#define ISMUX(sep) (((sep)->se_type == MUX_TYPE) || \ 338 ((sep)->se_type == MUXPLUS_TYPE)) 339#define ISMUXPLUS(sep) ((sep)->se_type == MUXPLUS_TYPE) 340 341 342void chargen_dg __P((int, struct servtab *)); 343void chargen_stream __P((int, struct servtab *)); 344void close_sep __P((struct servtab *)); 345void config __P((int)); 346void daytime_dg __P((int, struct servtab *)); 347void daytime_stream __P((int, struct servtab *)); 348void discard_dg __P((int, struct servtab *)); 349void discard_stream __P((int, struct servtab *)); 350void echo_dg __P((int, struct servtab *)); 351void echo_stream __P((int, struct servtab *)); 352void endconfig __P((void)); 353struct servtab *enter __P((struct servtab *)); 354void freeconfig __P((struct servtab *)); 355struct servtab *getconfigent __P((void)); 356void goaway __P((int)); 357void machtime_dg __P((int, struct servtab *)); 358void machtime_stream __P((int, struct servtab *)); 359char *newstr __P((char *)); 360char *nextline __P((FILE *)); 361void print_service __P((char *, struct servtab *)); 362void reapchild __P((int)); 363void retry __P((int)); 364void run_service __P((int, struct servtab *)); 365int setconfig __P((void)); 366void setup __P((struct servtab *)); 367#ifdef IPSEC 368int ipsecsetup __P((struct servtab *)); 369#endif 370char *sskip __P((char **)); 371char *skip __P((char **)); 372void tcpmux __P((int, struct servtab *)); 373void usage __P((void)); 374void register_rpc __P((struct servtab *sep)); 375void unregister_rpc __P((struct servtab *sep)); 376void bump_nofile __P((void)); 377void inetd_setproctitle __P((char *, int)); 378void initring __P((void)); 379long machtime __P((void)); 380int port_good_dg __P((struct sockaddr *sa)); 381static int getline __P((int, char *, int)); 382int main __P((int, char *[], char *[])); 383 384struct biltin { 385 char *bi_service; /* internally provided service name */ 386 int bi_socktype; /* type of socket supported */ 387 short bi_fork; /* 1 if should fork before call */ 388 short bi_wait; /* 1 if should wait for child */ 389 void (*bi_fn) __P((int, struct servtab *)); 390 /* function which performs it */ 391} biltins[] = { 392 /* Echo received data */ 393 { "echo", SOCK_STREAM, 1, 0, echo_stream }, 394 { "echo", SOCK_DGRAM, 0, 0, echo_dg }, 395 396 /* Internet /dev/null */ 397 { "discard", SOCK_STREAM, 1, 0, discard_stream }, 398 { "discard", SOCK_DGRAM, 0, 0, discard_dg }, 399 400 /* Return 32 bit time since 1970 */ 401 { "time", SOCK_STREAM, 0, 0, machtime_stream }, 402 { "time", SOCK_DGRAM, 0, 0, machtime_dg }, 403 404 /* Return human-readable time */ 405 { "daytime", SOCK_STREAM, 0, 0, daytime_stream }, 406 { "daytime", SOCK_DGRAM, 0, 0, daytime_dg }, 407 408 /* Familiar character generator */ 409 { "chargen", SOCK_STREAM, 1, 0, chargen_stream }, 410 { "chargen", SOCK_DGRAM, 0, 0, chargen_dg }, 411 412 { "tcpmux", SOCK_STREAM, 1, 0, tcpmux }, 413 414 { NULL } 415}; 416 417/* list of "bad" ports. I.e. ports that are most obviously used for 418 * "cycling packets" denial of service attacks. See /etc/services. 419 * List must end with port number "0". 420 */ 421 422u_int16_t bad_ports[] = { 7, 9, 13, 19, 37, 0}; 423 424 425#define NUMINT (sizeof(intab) / sizeof(struct inent)) 426char *CONFIG = _PATH_INETDCONF; 427char **Argv; 428char *LastArg; 429extern char *__progname; 430 431#ifdef sun 432/* 433 * Sun's RPC library caches the result of `dtablesize()' 434 * This is incompatible with our "bumping" of file descriptors "on demand" 435 */ 436int 437_rpc_dtablesize() 438{ 439 return rlim_ofile_cur; 440} 441#endif 442 443int 444main(argc, argv, envp) 445 int argc; 446 char *argv[], *envp[]; 447{ 448 struct servtab *sep, *nsep; 449 struct sigvec sv; 450 int ch, dofork; 451 pid_t pid; 452 453 Argv = argv; 454 if (envp == 0 || *envp == 0) 455 envp = argv; 456 while (*envp) 457 envp++; 458 LastArg = envp[-1] + strlen(envp[-1]); 459 460 while ((ch = getopt(argc, argv, 461#ifdef LIBWRAP 462 "dl" 463#else 464 "d" 465#endif 466 )) != -1) 467 switch(ch) { 468 case 'd': 469 debug = 1; 470 options |= SO_DEBUG; 471 break; 472#ifdef LIBWRAP 473 case 'l': 474 lflag = 1; 475 break; 476#endif 477 case '?': 478 default: 479 usage(); 480 } 481 argc -= optind; 482 argv += optind; 483 484 if (argc > 0) 485 CONFIG = argv[0]; 486 487 if (debug == 0) 488 daemon(0, 0); 489 openlog(__progname, LOG_PID | LOG_NOWAIT, LOG_DAEMON); 490 pidfile(NULL); 491 492#ifdef RLIMIT_NOFILE 493 if (getrlimit(RLIMIT_NOFILE, &rlim_ofile) < 0) { 494 syslog(LOG_ERR, "getrlimit: %m"); 495 } else { 496 rlim_ofile_cur = rlim_ofile.rlim_cur; 497 if (rlim_ofile_cur == RLIM_INFINITY) /* ! */ 498 rlim_ofile_cur = OPEN_MAX; 499 } 500#endif 501 502 memset(&sv, 0, sizeof(sv)); 503 sv.sv_mask = SIGBLOCK; 504 sv.sv_handler = retry; 505 sigvec(SIGALRM, &sv, (struct sigvec *)0); 506 config(SIGHUP); 507 sv.sv_handler = config; 508 sigvec(SIGHUP, &sv, (struct sigvec *)0); 509 sv.sv_handler = reapchild; 510 sigvec(SIGCHLD, &sv, (struct sigvec *)0); 511 sv.sv_handler = goaway; 512 sigvec(SIGTERM, &sv, (struct sigvec *)0); 513 sv.sv_handler = goaway; 514 sigvec(SIGINT, &sv, (struct sigvec *)0); 515 sv.sv_mask = 0L; 516 sv.sv_handler = SIG_IGN; 517 sigvec(SIGPIPE, &sv, (struct sigvec *)0); 518 519 { 520 /* space for daemons to overwrite environment for ps */ 521#define DUMMYSIZE 100 522 char dummy[DUMMYSIZE]; 523 524 (void)memset(dummy, 'x', DUMMYSIZE - 1); 525 dummy[DUMMYSIZE - 1] = '\0'; 526 527 (void)setenv("inetd_dummy", dummy, 1); 528 } 529 530 for (;;) { 531 int n, ctrl; 532 fd_set readable; 533 534 if (nsock == 0) { 535 (void) sigblock(SIGBLOCK); 536 while (nsock == 0) 537 sigpause(0L); 538 (void) sigsetmask(0L); 539 } 540 readable = allsock; 541 if ((n = select(maxsock + 1, &readable, (fd_set *)0, 542 (fd_set *)0, (struct timeval *)0)) <= 0) { 543 if (n == -1 && errno != EINTR) { 544 syslog(LOG_WARNING, "select: %m"); 545 sleep(1); 546 } 547 continue; 548 } 549 for (sep = servtab; n && sep; sep = nsep) { 550 nsep = sep->se_next; 551 if (sep->se_fd != -1 && FD_ISSET(sep->se_fd, &readable)) { 552 n--; 553 if (debug) 554 fprintf(stderr, "someone wants %s\n", sep->se_service); 555 if (!sep->se_wait && sep->se_socktype == SOCK_STREAM) { 556 /* XXX here do the libwrap check-before-accept */ 557 ctrl = accept(sep->se_fd, (struct sockaddr *)0, 558 (int *)0); 559 if (debug) 560 fprintf(stderr, "accept, ctrl %d\n", ctrl); 561 if (ctrl < 0) { 562 if (errno != EINTR) 563 syslog(LOG_WARNING, 564 "accept (for %s): %m", 565 sep->se_service); 566 continue; 567 } 568 } else 569 ctrl = sep->se_fd; 570 (void) sigblock(SIGBLOCK); 571 pid = 0; 572#ifdef LIBWRAP_INTERNAL 573 dofork = 1; 574#else 575 dofork = (sep->se_bi == 0 || sep->se_bi->bi_fork); 576#endif 577 if (dofork) { 578 if (sep->se_count++ == 0) 579 (void)gettimeofday(&sep->se_time, 580 (struct timezone *)0); 581 else if (sep->se_count >= sep->se_max) { 582 struct timeval now; 583 584 (void)gettimeofday(&now, (struct timezone *)0); 585 if (now.tv_sec - sep->se_time.tv_sec > 586 CNT_INTVL) { 587 sep->se_time = now; 588 sep->se_count = 1; 589 } else { 590 syslog(LOG_ERR, 591 "%s/%s server failing (looping), service terminated\n", 592 sep->se_service, sep->se_proto); 593 if (!sep->se_wait && sep->se_socktype == SOCK_STREAM) 594 close(ctrl); 595 close_sep(sep); 596 sigsetmask(0L); 597 if (!timingout) { 598 timingout = 1; 599 alarm(RETRYTIME); 600 } 601 continue; 602 } 603 } 604 pid = fork(); 605 if (pid < 0) { 606 syslog(LOG_ERR, "fork: %m"); 607 if (!sep->se_wait && sep->se_socktype == SOCK_STREAM) 608 close(ctrl); 609 sigsetmask(0L); 610 sleep(1); 611 continue; 612 } 613 if (pid != 0 && sep->se_wait) { 614 sep->se_wait = pid; 615 FD_CLR(sep->se_fd, &allsock); 616 nsock--; 617 } 618 if (pid == 0) { 619 sv.sv_mask = 0L; 620 sv.sv_handler = SIG_DFL; 621 sigvec(SIGPIPE, &sv, (struct sigvec *)0); 622 if (debug) 623 setsid(); 624 } 625 } 626 sigsetmask(0L); 627 if (pid == 0) { 628 run_service(ctrl, sep); 629 if (dofork) 630 exit(0); 631 } 632 if (!sep->se_wait && sep->se_socktype == SOCK_STREAM) 633 close(ctrl); 634 } 635 } 636 } 637} 638 639void 640run_service(ctrl, sep) 641 int ctrl; 642 struct servtab *sep; 643{ 644 struct passwd *pwd; 645 struct group *grp = NULL; /* XXX gcc */ 646 char buf[7]; 647#ifdef LIBWRAP 648 struct request_info req; 649 int denied; 650 char *service = NULL; /* XXX gcc */ 651#endif 652 653#ifdef LIBWRAP 654#ifndef LIBWRAP_INTERNAL 655 if (sep->se_bi == 0) 656#endif 657 if (!sep->se_wait && sep->se_socktype == SOCK_STREAM) { 658 request_init(&req, RQ_DAEMON, sep->se_argv[0] ? 659 sep->se_argv[0] : sep->se_service, RQ_FILE, ctrl, NULL); 660 fromhost(&req); 661 denied = !hosts_access(&req); 662 if (denied || lflag) { 663 sp = getservbyport(sep->se_ctrladdr_in.sin_port, 664 sep->se_proto); 665 if (sp == NULL) { 666 (void)snprintf(buf, sizeof buf, "%d", 667 ntohs(sep->se_ctrladdr_in.sin_port)); 668 service = buf; 669 } else 670 service = sp->s_name; 671 } 672 if (denied) { 673 syslog(deny_severity, 674 "refused connection from %.500s, service %s (%s)", 675 eval_client(&req), service, sep->se_proto); 676 goto reject; 677 } 678 if (lflag) { 679 syslog(allow_severity, 680 "connection from %.500s, service %s (%s)", 681 eval_client(&req), service, sep->se_proto); 682 } 683 } 684#endif /* LIBWRAP */ 685 686 if (sep->se_bi) { 687 (*sep->se_bi->bi_fn)(ctrl, sep); 688 } else { 689 if ((pwd = getpwnam(sep->se_user)) == NULL) { 690 syslog(LOG_ERR, "%s/%s: %s: No such user", 691 sep->se_service, sep->se_proto, sep->se_user); 692 goto reject; 693 } 694 if (sep->se_group && 695 (grp = getgrnam(sep->se_group)) == NULL) { 696 syslog(LOG_ERR, "%s/%s: %s: No such group", 697 sep->se_service, sep->se_proto, sep->se_group); 698 goto reject; 699 } 700 if (pwd->pw_uid) { 701 if (sep->se_group) 702 pwd->pw_gid = grp->gr_gid; 703 if (setgid(pwd->pw_gid) < 0) { 704 syslog(LOG_ERR, 705 "%s/%s: can't set gid %d: %m", sep->se_service, 706 sep->se_proto, pwd->pw_gid); 707 goto reject; 708 } 709 (void) initgroups(pwd->pw_name, 710 pwd->pw_gid); 711 if (setuid(pwd->pw_uid) < 0) { 712 syslog(LOG_ERR, 713 "%s/%s: can't set uid %d: %m", sep->se_service, 714 sep->se_proto, pwd->pw_uid); 715 goto reject; 716 } 717 } else if (sep->se_group) { 718 (void) setgid((gid_t)grp->gr_gid); 719 } 720 if (debug) 721 fprintf(stderr, "%d execl %s\n", 722 getpid(), sep->se_server); 723#ifdef MULOG 724 if (sep->se_log) 725 dolog(sep, ctrl); 726#endif 727 /* Set our control descriptor to not close-on-exec... */ 728 if (fcntl(ctrl, F_SETFD, 0) < 0) 729 syslog(LOG_ERR, "fcntl (F_SETFD, 0): %m"); 730 /* ...and dup it to stdin, stdout, and stderr. */ 731 if (ctrl != 0) { 732 dup2(ctrl, 0); 733 close(ctrl); 734 ctrl = 0; 735 } 736 dup2(0, 1); 737 dup2(0, 2); 738#ifdef RLIMIT_NOFILE 739 if (rlim_ofile.rlim_cur != rlim_ofile_cur && 740 setrlimit(RLIMIT_NOFILE, &rlim_ofile) < 0) 741 syslog(LOG_ERR, "setrlimit: %m"); 742#endif 743 execv(sep->se_server, sep->se_argv); 744 syslog(LOG_ERR, "cannot execute %s: %m", sep->se_server); 745 reject: 746 if (sep->se_socktype != SOCK_STREAM) 747 recv(ctrl, buf, sizeof (buf), 0); 748 _exit(1); 749 } 750} 751 752void 753reapchild(signo) 754 int signo; 755{ 756 int status; 757 pid_t pid; 758 struct servtab *sep; 759 760 for (;;) { 761 pid = wait3(&status, WNOHANG, (struct rusage *)0); 762 if (pid <= 0) 763 break; 764 if (debug) 765 fprintf(stderr, "%d reaped, status %#x\n", 766 pid, status); 767 for (sep = servtab; sep; sep = sep->se_next) 768 if (sep->se_wait == pid) { 769 if (WIFEXITED(status) && WEXITSTATUS(status)) 770 syslog(LOG_WARNING, 771 "%s: exit status 0x%x", 772 sep->se_server, WEXITSTATUS(status)); 773 else if (WIFSIGNALED(status)) 774 syslog(LOG_WARNING, 775 "%s: exit signal 0x%x", 776 sep->se_server, WTERMSIG(status)); 777 sep->se_wait = 1; 778 FD_SET(sep->se_fd, &allsock); 779 nsock++; 780 if (debug) 781 fprintf(stderr, "restored %s, fd %d\n", 782 sep->se_service, sep->se_fd); 783 } 784 } 785} 786 787void 788config(signo) 789 int signo; 790{ 791 struct servtab *sep, *cp, **sepp; 792 long omask; 793 int n; 794 795 if (!setconfig()) { 796 syslog(LOG_ERR, "%s: %m", CONFIG); 797 return; 798 } 799 for (sep = servtab; sep; sep = sep->se_next) 800 sep->se_checked = 0; 801 while ((cp = getconfigent())) { 802 for (sep = servtab; sep; sep = sep->se_next) 803 if (strcmp(sep->se_service, cp->se_service) == 0 && 804 strcmp(sep->se_hostaddr, cp->se_hostaddr) == 0 && 805 strcmp(sep->se_proto, cp->se_proto) == 0 && 806 ISMUX(sep) == ISMUX(cp)) 807 break; 808 if (sep != 0) { 809 int i; 810 811#define SWAP(type, a, b) {type c=(type)a; (type)a=(type)b; (type)b=(type)c;} 812 813 omask = sigblock(SIGBLOCK); 814 /* 815 * sep->se_wait may be holding the pid of a daemon 816 * that we're waiting for. If so, don't overwrite 817 * it unless the config file explicitly says don't 818 * wait. 819 */ 820 if (cp->se_bi == 0 && 821 (sep->se_wait == 1 || cp->se_wait == 0)) 822 sep->se_wait = cp->se_wait; 823 SWAP(char *, sep->se_user, cp->se_user); 824 SWAP(char *, sep->se_group, cp->se_group); 825 SWAP(char *, sep->se_server, cp->se_server); 826 for (i = 0; i < MAXARGV; i++) 827 SWAP(char *, sep->se_argv[i], cp->se_argv[i]); 828#ifdef IPSEC 829 SWAP(char *, sep->se_policy, cp->se_policy); 830 if (sep->se_fd != -1) { 831 if (ipsecsetup(sep) < 0 && sep->se_policy) { 832 syslog(LOG_ERR, 833 "%s: ipsec initialization failed", 834 sep->se_service); 835 sep->se_checked = 0; 836 continue; 837 } 838 } 839#endif 840 SWAP(int, cp->se_type, sep->se_type); 841 SWAP(int, cp->se_max, sep->se_max); 842#undef SWAP 843 if (isrpcservice(sep)) 844 unregister_rpc(sep); 845 sep->se_rpcversl = cp->se_rpcversl; 846 sep->se_rpcversh = cp->se_rpcversh; 847 sigsetmask(omask); 848 freeconfig(cp); 849 if (debug) 850 print_service("REDO", sep); 851 } else { 852 sep = enter(cp); 853 if (debug) 854 print_service("ADD ", sep); 855 } 856 sep->se_checked = 1; 857 858 switch (sep->se_family) { 859 case AF_LOCAL: 860 if (sep->se_fd != -1) 861 break; 862 n = strlen(sep->se_service); 863 if (n > sizeof(sep->se_ctrladdr_un.sun_path)) { 864 syslog(LOG_ERR, "%s: address too long", 865 sep->se_service); 866 sep->se_checked = 0; 867 continue; 868 } 869 (void)unlink(sep->se_service); 870 strncpy(sep->se_ctrladdr_un.sun_path, 871 sep->se_service, n); 872 sep->se_ctrladdr_un.sun_family = AF_LOCAL; 873 sep->se_ctrladdr_size = n + 874 sizeof(sep->se_ctrladdr_un) - 875 sizeof(sep->se_ctrladdr_un.sun_path); 876 if (!ISMUX(sep)) 877 setup(sep); 878 break; 879 case AF_INET: 880 case AF_INET6: 881 { 882 struct addrinfo hints, *res; 883 char *host, *port; 884 int error; 885 886 memset(&hints, 0, sizeof(hints)); 887 hints.ai_family = sep->se_family; 888 hints.ai_socktype = sep->se_socktype; 889 if (!strcmp(sep->se_hostaddr, "*")) { 890 hints.ai_flags = AI_PASSIVE; 891 host = NULL; 892 } else 893 host = sep->se_hostaddr; 894 if (isrpcservice(sep) || ISMUX(sep)) 895 port = "0"; 896 else 897 port = sep->se_service; 898 error = getaddrinfo(host, port, &hints, &res); 899 if (error) { 900 syslog(LOG_ERR, "%s/%s: %s: %s", 901 sep->se_service, sep->se_proto, 902 sep->se_hostaddr, gai_strerror(error)); 903 sep->se_checked = 0; 904 continue; 905 } 906 if (res->ai_next) { 907 syslog(LOG_ERR, 908 "%s/%s: %s: resolved to multiple addr", 909 sep->se_service, sep->se_proto, 910 sep->se_hostaddr); 911 sep->se_checked = 0; 912 freeaddrinfo(res); 913 continue; 914 } 915 memcpy(&sep->se_ctrladdr, res->ai_addr, 916 res->ai_addrlen); 917 if (ISMUX(sep)) { 918 sep->se_fd = -1; 919 freeaddrinfo(res); 920 continue; 921 } 922 sep->se_ctrladdr_size = res->ai_addrlen; 923 freeaddrinfo(res); 924 if (isrpcservice(sep)) { 925 struct rpcent *rp; 926 927 sep->se_rpcprog = atoi(sep->se_service); 928 if (sep->se_rpcprog == 0) { 929 rp = getrpcbyname(sep->se_service); 930 if (rp == 0) { 931 syslog(LOG_ERR, 932 "%s/%s: unknown service", 933 sep->se_service, 934 sep->se_proto); 935 sep->se_checked = 0; 936 continue; 937 } 938 sep->se_rpcprog = rp->r_number; 939 } 940 if (sep->se_fd == -1 && !ISMUX(sep)) 941 setup(sep); 942 if (sep->se_fd != -1) 943 register_rpc(sep); 944 } else { 945 if (sep->se_fd >= 0) 946 close_sep(sep); 947 if (sep->se_fd == -1 && !ISMUX(sep)) 948 setup(sep); 949 } 950 } 951 } 952 } 953 endconfig(); 954 /* 955 * Purge anything not looked at above. 956 */ 957 omask = sigblock(SIGBLOCK); 958 sepp = &servtab; 959 while ((sep = *sepp)) { 960 if (sep->se_checked) { 961 sepp = &sep->se_next; 962 continue; 963 } 964 *sepp = sep->se_next; 965 if (sep->se_fd >= 0) 966 close_sep(sep); 967 if (isrpcservice(sep)) 968 unregister_rpc(sep); 969 if (sep->se_family == AF_LOCAL) 970 (void)unlink(sep->se_service); 971 if (debug) 972 print_service("FREE", sep); 973 freeconfig(sep); 974 free((char *)sep); 975 } 976 (void) sigsetmask(omask); 977} 978 979void 980retry(signo) 981 int signo; 982{ 983 struct servtab *sep; 984 985 timingout = 0; 986 for (sep = servtab; sep; sep = sep->se_next) { 987 if (sep->se_fd == -1 && !ISMUX(sep)) { 988 switch (sep->se_family) { 989 case AF_LOCAL: 990 case AF_INET: 991 case AF_INET6: 992 setup(sep); 993 if (sep->se_fd != -1 && isrpcservice(sep)) 994 register_rpc(sep); 995 break; 996 } 997 } 998 } 999} 1000 1001void 1002goaway(signo) 1003 int signo; 1004{ 1005 struct servtab *sep; 1006 1007 for (sep = servtab; sep; sep = sep->se_next) { 1008 if (sep->se_fd == -1) 1009 continue; 1010 1011 switch (sep->se_family) { 1012 case AF_LOCAL: 1013 (void)unlink(sep->se_service); 1014 break; 1015 case AF_INET: 1016 case AF_INET6: 1017 if (sep->se_wait == 1 && isrpcservice(sep)) 1018 unregister_rpc(sep); 1019 break; 1020 } 1021 (void)close(sep->se_fd); 1022 } 1023 exit(0); 1024} 1025 1026void 1027setup(sep) 1028 struct servtab *sep; 1029{ 1030 int on = 1; 1031 1032 if ((sep->se_fd = socket(sep->se_family, sep->se_socktype, 0)) < 0) { 1033 if (debug) 1034 fprintf(stderr, "socket failed on %s/%s: %s\n", 1035 sep->se_service, sep->se_proto, strerror(errno)); 1036 syslog(LOG_ERR, "%s/%s: socket: %m", 1037 sep->se_service, sep->se_proto); 1038 return; 1039 } 1040 /* Set all listening sockets to close-on-exec. */ 1041 if (fcntl(sep->se_fd, F_SETFD, FD_CLOEXEC) < 0) 1042 syslog(LOG_ERR, "fcntl (F_SETFD, FD_CLOEXEC): %m"); 1043 1044#define turnon(fd, opt) \ 1045setsockopt(fd, SOL_SOCKET, opt, (char *)&on, sizeof (on)) 1046 if (strcmp(sep->se_proto, "tcp") == 0 && (options & SO_DEBUG) && 1047 turnon(sep->se_fd, SO_DEBUG) < 0) 1048 syslog(LOG_ERR, "setsockopt (SO_DEBUG): %m"); 1049 if (turnon(sep->se_fd, SO_REUSEADDR) < 0) 1050 syslog(LOG_ERR, "setsockopt (SO_REUSEADDR): %m"); 1051#undef turnon 1052 1053 /* Set the socket buffer sizes, if specified. */ 1054 if (sep->se_sndbuf != 0 && setsockopt(sep->se_fd, SOL_SOCKET, 1055 SO_SNDBUF, (char *)&sep->se_sndbuf, sizeof(sep->se_sndbuf)) < 0) 1056 syslog(LOG_ERR, "setsockopt (SO_SNDBUF %d): %m", 1057 sep->se_sndbuf); 1058 if (sep->se_rcvbuf != 0 && setsockopt(sep->se_fd, SOL_SOCKET, 1059 SO_RCVBUF, (char *)&sep->se_rcvbuf, sizeof(sep->se_rcvbuf)) < 0) 1060 syslog(LOG_ERR, "setsockopt (SO_RCVBUF %d): %m", 1061 sep->se_rcvbuf); 1062#ifdef IPSEC 1063 if (ipsecsetup(sep) < 0 && sep->se_policy) { 1064 syslog(LOG_ERR, "%s/%s: ipsec setup failed", 1065 sep->se_service, sep->se_proto); 1066 close(sep->se_fd); 1067 return; 1068 } 1069#endif 1070 1071 if (bind(sep->se_fd, &sep->se_ctrladdr, sep->se_ctrladdr_size) < 0) { 1072 if (debug) 1073 fprintf(stderr, "bind failed on %s/%s: %s\n", 1074 sep->se_service, sep->se_proto, strerror(errno)); 1075 syslog(LOG_ERR, "%s/%s: bind: %m", 1076 sep->se_service, sep->se_proto); 1077 (void) close(sep->se_fd); 1078 sep->se_fd = -1; 1079 if (!timingout) { 1080 timingout = 1; 1081 alarm(RETRYTIME); 1082 } 1083 return; 1084 } 1085 if (sep->se_socktype == SOCK_STREAM) 1086 listen(sep->se_fd, 10); 1087 1088 FD_SET(sep->se_fd, &allsock); 1089 nsock++; 1090 if (sep->se_fd > maxsock) { 1091 maxsock = sep->se_fd; 1092 if (maxsock > rlim_ofile_cur - FD_MARGIN) 1093 bump_nofile(); 1094 } 1095 if (debug) 1096 fprintf(stderr, "registered %s on %d\n", 1097 sep->se_server, sep->se_fd); 1098} 1099 1100#ifdef IPSEC 1101int 1102ipsecsetup(sep) 1103 struct servtab *sep; 1104{ 1105 int len; 1106 char *buf; 1107 char *policy; 1108 int level, opt; 1109 int ret; 1110 1111 switch (sep->se_family) { 1112 case AF_INET: 1113 level = IPPROTO_IP; 1114 opt = IP_IPSEC_POLICY; 1115 break; 1116 case AF_INET6: 1117 level = IPPROTO_IPV6; 1118 opt = IPV6_IPSEC_POLICY; 1119 break; 1120 default: 1121 return -1; 1122 } 1123 1124 if (!sep->se_policy || sep->se_policy[0] == '\0') 1125 policy = "entrust"; 1126 else 1127 policy = sep->se_policy; 1128 1129 len = ipsec_get_policylen(policy); 1130 if (len < 0) { 1131 syslog(LOG_ERR, "invalid security policy \"%s\"", policy); 1132 return -1; 1133 } 1134 buf = (char *)malloc(len); 1135 if (buf != NULL) { 1136 ipsec_set_policy(buf, len, policy); 1137 ret = setsockopt(sep->se_fd, level, opt, buf, len); 1138 free(buf); 1139 } else 1140 ret = -1; 1141 1142 return ret; 1143} 1144#endif 1145 1146/* 1147 * Finish with a service and its socket. 1148 */ 1149void 1150close_sep(sep) 1151 struct servtab *sep; 1152{ 1153 if (sep->se_fd >= 0) { 1154 nsock--; 1155 FD_CLR(sep->se_fd, &allsock); 1156 (void) close(sep->se_fd); 1157 sep->se_fd = -1; 1158 } 1159 sep->se_count = 0; 1160 /* 1161 * Don't keep the pid of this running deamon: when reapchild() 1162 * reaps this pid, it would erroneously increment nsock. 1163 */ 1164 if (sep->se_wait > 1) 1165 sep->se_wait = 1; 1166} 1167 1168void 1169register_rpc(sep) 1170 struct servtab *sep; 1171{ 1172#ifdef RPC 1173 int n; 1174 struct sockaddr_storage ss; 1175 struct sockaddr_in *sin = (struct sockaddr_in *)&ss; 1176 struct protoent *pp; 1177 1178 if ((pp = getprotobyname(sep->se_proto+4)) == NULL) { 1179 syslog(LOG_ERR, "%s: getproto: %m", 1180 sep->se_proto); 1181 return; 1182 } 1183 n = sizeof ss; 1184 if (getsockname(sep->se_fd, (struct sockaddr *)&ss, &n) < 0) { 1185 syslog(LOG_ERR, "%s/%s: getsockname: %m", 1186 sep->se_service, sep->se_proto); 1187 return; 1188 } 1189 if (ss.ss_family != AF_INET) { /*XXX*/ 1190 syslog(LOG_ERR, "%s/%s: rpc not supported", 1191 sep->se_service, sep->se_proto); 1192 return; 1193 } 1194 1195 for (n = sep->se_rpcversl; n <= sep->se_rpcversh; n++) { 1196 if (debug) 1197 fprintf(stderr, "pmap_set: %u %u %u %u\n", 1198 sep->se_rpcprog, n, pp->p_proto, 1199 ntohs(sin->sin_port)); 1200 (void)pmap_unset(sep->se_rpcprog, n); 1201 if (!pmap_set(sep->se_rpcprog, n, pp->p_proto, ntohs(sin->sin_port))) 1202 syslog(LOG_ERR, "pmap_set: %u %u %u %u: %m", 1203 sep->se_rpcprog, n, pp->p_proto, 1204 ntohs(sin->sin_port)); 1205 } 1206#endif /* RPC */ 1207} 1208 1209void 1210unregister_rpc(sep) 1211 struct servtab *sep; 1212{ 1213#ifdef RPC 1214 int n; 1215 1216 for (n = sep->se_rpcversl; n <= sep->se_rpcversh; n++) { 1217 if (debug) 1218 fprintf(stderr, "pmap_unset(%u, %u)\n", 1219 sep->se_rpcprog, n); 1220 if (!pmap_unset(sep->se_rpcprog, n)) 1221 syslog(LOG_ERR, "pmap_unset(%u, %u)\n", 1222 sep->se_rpcprog, n); 1223 } 1224#endif /* RPC */ 1225} 1226 1227 1228struct servtab * 1229enter(cp) 1230 struct servtab *cp; 1231{ 1232 struct servtab *sep; 1233 long omask; 1234 1235 sep = (struct servtab *)malloc(sizeof (*sep)); 1236 if (sep == (struct servtab *)0) { 1237 syslog(LOG_ERR, "Out of memory."); 1238 exit(-1); 1239 } 1240 *sep = *cp; 1241 sep->se_fd = -1; 1242 sep->se_rpcprog = -1; 1243 omask = sigblock(SIGBLOCK); 1244 sep->se_next = servtab; 1245 servtab = sep; 1246 sigsetmask(omask); 1247 return (sep); 1248} 1249 1250FILE *fconfig = NULL; 1251struct servtab serv; 1252char line[LINE_MAX]; 1253char *defhost; 1254 1255int 1256setconfig() 1257{ 1258 if (defhost) free(defhost); 1259 defhost = newstr("*"); 1260 if (fconfig != NULL) { 1261 fseek(fconfig, 0L, SEEK_SET); 1262 return (1); 1263 } 1264 fconfig = fopen(CONFIG, "r"); 1265 return (fconfig != NULL); 1266} 1267 1268void 1269endconfig() 1270{ 1271 if (fconfig) { 1272 (void) fclose(fconfig); 1273 fconfig = NULL; 1274 } 1275 if (defhost) { 1276 free(defhost); 1277 defhost = 0; 1278 } 1279} 1280 1281struct servtab * 1282getconfigent() 1283{ 1284 struct servtab *sep = &serv; 1285 int argc, val; 1286 char *cp, *cp0, *arg, *buf0, *buf1, *sz0, *sz1; 1287 static char TCPMUX_TOKEN[] = "tcpmux/"; 1288#define MUX_LEN (sizeof(TCPMUX_TOKEN)-1) 1289 char *hostdelim; 1290#ifdef IPSEC 1291 char *policy = NULL; 1292#endif 1293 1294more: 1295 while ((cp = nextline(fconfig))) { 1296#ifdef IPSEC 1297 /* lines starting with #@ is not a comment, but the policy */ 1298 if (cp[0] == '#' && cp[1] == '@') { 1299 char *p; 1300 for (p = cp + 2; p && *p && isspace(*p); p++) 1301 ; 1302 if (*p == '\0') { 1303 if (policy) 1304 free(policy); 1305 policy = NULL; 1306 } else if (ipsec_get_policylen(p) >= 0) { 1307 if (policy) 1308 free(policy); 1309 policy = newstr(p); 1310 } else { 1311 syslog(LOG_ERR, 1312 "%s: invalid ipsec policy \"%s\"", 1313 CONFIG, p); 1314 exit(-1); 1315 } 1316 } 1317#endif 1318 if (*cp == '#' || *cp == '\0') 1319 continue; 1320#ifdef MULOG 1321 /* Avoid use of `skip' if there is a danger of it looking 1322 * at continuation lines. 1323 */ 1324 do { 1325 cp++; 1326 } while (*cp == ' ' || *cp == '\t'); 1327 if (*cp == '\0') 1328 continue; 1329 if ((arg = skip(&cp)) == NULL) 1330 continue; 1331 if (strcmp(arg, "DOMAIN")) 1332 continue; 1333 if (curdom) 1334 free(curdom); 1335 curdom = NULL; 1336 while (*cp == ' ' || *cp == '\t') 1337 cp++; 1338 if (*cp == '\0') 1339 continue; 1340 arg = cp; 1341 while (*cp && *cp != ' ' && *cp != '\t') 1342 cp++; 1343 if (*cp != '\0') 1344 *cp++ = '\0'; 1345 curdom = newstr(arg); 1346#endif 1347 break; 1348 } 1349 if (cp == NULL) 1350 return ((struct servtab *)0); 1351 /* 1352 * clear the static buffer, since some fields (se_ctrladdr, 1353 * for example) don't get initialized here. 1354 */ 1355 memset((caddr_t)sep, 0, sizeof *sep); 1356 arg = skip(&cp); 1357 if (cp == NULL) { 1358 /* got an empty line containing just blanks/tabs. */ 1359 goto more; 1360 } 1361 /* Check for a host name. */ 1362 hostdelim = strrchr(arg, ':'); 1363 if (hostdelim) { 1364 *hostdelim = '\0'; 1365 sep->se_hostaddr = newstr(arg); 1366 arg = hostdelim + 1; 1367 /* 1368 * If the line is of the form `host:', then just change the 1369 * default host for the following lines. 1370 */ 1371 if (*arg == '\0') { 1372 arg = skip(&cp); 1373 if (cp == NULL) { 1374 free(defhost); 1375 defhost = sep->se_hostaddr; 1376 goto more; 1377 } 1378 } 1379 } else 1380 sep->se_hostaddr = newstr(defhost); 1381 if (strncmp(arg, TCPMUX_TOKEN, MUX_LEN) == 0) { 1382 char *c = arg + MUX_LEN; 1383 if (*c == '+') { 1384 sep->se_type = MUXPLUS_TYPE; 1385 c++; 1386 } else 1387 sep->se_type = MUX_TYPE; 1388 sep->se_service = newstr(c); 1389 } else { 1390 sep->se_service = newstr(arg); 1391 sep->se_type = NORM_TYPE; 1392 } 1393 1394 arg = sskip(&cp); 1395 if (strcmp(arg, "stream") == 0) 1396 sep->se_socktype = SOCK_STREAM; 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 sep->se_proto = newstr(sskip(&cp)); 1409 1410#define MALFORMED(arg) \ 1411do { \ 1412 syslog(LOG_ERR, "%s: malformed buffer size option `%s'", \ 1413 sep->se_service, (arg)); \ 1414 goto more; \ 1415} while (0) 1416 1417#define GETVAL(arg) \ 1418do { \ 1419 if (!isdigit(*(arg))) \ 1420 MALFORMED(arg); \ 1421 val = strtol((arg), &cp0, 10); \ 1422 if (cp0 != NULL) { \ 1423 if (cp0[1] != '\0') \ 1424 MALFORMED((arg)); \ 1425 if (cp0[0] == 'k') \ 1426 val *= 1024; \ 1427 if (cp0[0] == 'm') \ 1428 val *= 1024 * 1024; \ 1429 } \ 1430 if (val < 1) { \ 1431 syslog(LOG_ERR, "%s: invalid buffer size `%s'", \ 1432 sep->se_service, (arg)); \ 1433 goto more; \ 1434 } \ 1435} while (0) 1436 1437#define ASSIGN(arg) \ 1438do { \ 1439 if (strcmp((arg), "sndbuf") == 0) \ 1440 sep->se_sndbuf = val; \ 1441 else if (strcmp((arg), "rcvbuf") == 0) \ 1442 sep->se_rcvbuf = val; \ 1443 else \ 1444 MALFORMED((arg)); \ 1445} while (0) 1446 1447 /* 1448 * Extract the send and receive buffer sizes before parsing 1449 * the protocol. 1450 */ 1451 sep->se_sndbuf = sep->se_rcvbuf = 0; 1452 buf0 = buf1 = sz0 = sz1 = NULL; 1453 if ((buf0 = strchr(sep->se_proto, ',')) != NULL) { 1454 /* Not meaningful for Tcpmux services. */ 1455 if (sep->se_type != NORM_TYPE) { 1456 syslog(LOG_ERR, "%s: can't specify buffer sizes for " 1457 "tcpmux services", sep->se_service); 1458 goto more; 1459 } 1460 1461 /* Skip the , */ 1462 *buf0++ = '\0'; 1463 1464 /* Check to see if another socket buffer size was specified. */ 1465 if ((buf1 = strchr(buf0, ',')) != NULL) { 1466 /* Skip the , */ 1467 *buf1++ = '\0'; 1468 1469 /* Make sure a 3rd one wasn't specified. */ 1470 if (strchr(buf1, ',') != NULL) { 1471 syslog(LOG_ERR, "%s: too many buffer sizes", 1472 sep->se_service); 1473 goto more; 1474 } 1475 1476 /* Locate the size. */ 1477 if ((sz1 = strchr(buf1, '=')) == NULL) 1478 MALFORMED(buf1); 1479 1480 /* Skip the = */ 1481 *sz1++ = '\0'; 1482 } 1483 1484 /* Locate the size. */ 1485 if ((sz0 = strchr(buf0, '=')) == NULL) 1486 MALFORMED(buf0); 1487 1488 /* Skip the = */ 1489 *sz0++ = '\0'; 1490 1491 GETVAL(sz0); 1492 ASSIGN(buf0); 1493 1494 if (buf1 != NULL) { 1495 GETVAL(sz1); 1496 ASSIGN(buf1); 1497 } 1498 } 1499 1500#undef ASSIGN 1501#undef GETVAL 1502#undef MALFORMED 1503 1504 if (strcmp(sep->se_proto, "unix") == 0) { 1505 sep->se_family = AF_LOCAL; 1506 } else { 1507 val = strlen(sep->se_proto); 1508 if (!val) { 1509 syslog(LOG_ERR, "%s: invalid protocol specified", 1510 sep->se_service); 1511 goto more; 1512 } 1513 val = sep->se_proto[val - 1]; 1514 switch (val) { 1515 case '4': /*tcp4 or udp4*/ 1516 sep->se_family = AF_INET; 1517 break; 1518 case '6': /*tcp6 or udp6*/ 1519 sep->se_family = AF_INET6; 1520 break; 1521 default: 1522 sep->se_family = AF_INET; /*will become AF_INET6*/ 1523 break; 1524 } 1525 if (strncmp(sep->se_proto, "rpc/", 4) == 0) { 1526#ifdef RPC 1527 char *cp, *ccp; 1528 cp = strchr(sep->se_service, '/'); 1529 if (cp == 0) { 1530 syslog(LOG_ERR, "%s: no rpc version", 1531 sep->se_service); 1532 goto more; 1533 } 1534 *cp++ = '\0'; 1535 sep->se_rpcversl = sep->se_rpcversh = 1536 strtol(cp, &ccp, 0); 1537 if (ccp == cp) { 1538 badafterall: 1539 syslog(LOG_ERR, "%s/%s: bad rpc version", 1540 sep->se_service, cp); 1541 goto more; 1542 } 1543 if (*ccp == '-') { 1544 cp = ccp + 1; 1545 sep->se_rpcversh = strtol(cp, &ccp, 0); 1546 if (ccp == cp) 1547 goto badafterall; 1548 } 1549#else 1550 syslog(LOG_ERR, "%s: rpc services not suported", 1551 sep->se_service); 1552 goto more; 1553#endif /* RPC */ 1554 } 1555 } 1556 arg = sskip(&cp); 1557 { 1558 char *cp; 1559 cp = strchr(arg, '.'); 1560 if (cp) { 1561 *cp++ = '\0'; 1562 sep->se_max = atoi(cp); 1563 } else 1564 sep->se_max = TOOMANY; 1565 } 1566 sep->se_wait = strcmp(arg, "wait") == 0; 1567 if (ISMUX(sep)) { 1568 /* 1569 * Silently enforce "nowait" for TCPMUX services since 1570 * they don't have an assigned port to listen on. 1571 */ 1572 sep->se_wait = 0; 1573 1574 if (strncmp(sep->se_proto, "tcp", 3)) { 1575 syslog(LOG_ERR, 1576 "%s: bad protocol for tcpmux service %s", 1577 CONFIG, sep->se_service); 1578 goto more; 1579 } 1580 if (sep->se_socktype != SOCK_STREAM) { 1581 syslog(LOG_ERR, 1582 "%s: bad socket type for tcpmux service %s", 1583 CONFIG, sep->se_service); 1584 goto more; 1585 } 1586 } 1587 sep->se_user = newstr(sskip(&cp)); 1588 if ((sep->se_group = strchr(sep->se_user, '.'))) 1589 *sep->se_group++ = '\0'; 1590 sep->se_server = newstr(sskip(&cp)); 1591 if (strcmp(sep->se_server, "internal") == 0) { 1592 struct biltin *bi; 1593 1594 for (bi = biltins; bi->bi_service; bi++) 1595 if (bi->bi_socktype == sep->se_socktype && 1596 strcmp(bi->bi_service, sep->se_service) == 0) 1597 break; 1598 if (bi->bi_service == 0) { 1599 syslog(LOG_ERR, "internal service %s unknown", 1600 sep->se_service); 1601 goto more; 1602 } 1603 sep->se_bi = bi; 1604 sep->se_wait = bi->bi_wait; 1605 } else 1606 sep->se_bi = NULL; 1607 argc = 0; 1608 for (arg = skip(&cp); cp; arg = skip(&cp)) { 1609#if MULOG 1610 char *colon; 1611 1612 if (argc == 0 && (colon = strrchr(arg, ':'))) { 1613 while (arg < colon) { 1614 int x; 1615 char *ccp; 1616 1617 switch (*arg++) { 1618 case 'l': 1619 x = 1; 1620 if (isdigit(*arg)) { 1621 x = strtol(arg, &ccp, 0); 1622 if (ccp == arg) 1623 break; 1624 arg = ccp; 1625 } 1626 sep->se_log &= ~MULOG_RFC931; 1627 sep->se_log |= x; 1628 break; 1629 case 'a': 1630 sep->se_log |= MULOG_RFC931; 1631 break; 1632 default: 1633 break; 1634 } 1635 } 1636 arg = colon + 1; 1637 } 1638#endif 1639 if (argc < MAXARGV) 1640 sep->se_argv[argc++] = newstr(arg); 1641 } 1642 while (argc <= MAXARGV) 1643 sep->se_argv[argc++] = NULL; 1644#ifdef IPSEC 1645 sep->se_policy = policy ? newstr(policy) : NULL; 1646#endif 1647 return (sep); 1648} 1649 1650void 1651freeconfig(cp) 1652 struct servtab *cp; 1653{ 1654 int i; 1655 1656 if (cp->se_hostaddr) 1657 free(cp->se_hostaddr); 1658 if (cp->se_service) 1659 free(cp->se_service); 1660 if (cp->se_proto) 1661 free(cp->se_proto); 1662 if (cp->se_user) 1663 free(cp->se_user); 1664 /* Note: se_group is part of the newstr'ed se_user */ 1665 if (cp->se_server) 1666 free(cp->se_server); 1667 for (i = 0; i < MAXARGV; i++) 1668 if (cp->se_argv[i]) 1669 free(cp->se_argv[i]); 1670#ifdef IPSEC 1671 if (cp->se_policy) 1672 free(cp->se_policy); 1673#endif 1674} 1675 1676 1677/* 1678 * Safe skip - if skip returns null, log a syntax error in the 1679 * configuration file and exit. 1680 */ 1681char * 1682sskip(cpp) 1683 char **cpp; 1684{ 1685 char *cp; 1686 1687 cp = skip(cpp); 1688 if (cp == NULL) { 1689 syslog(LOG_ERR, "%s: syntax error", CONFIG); 1690 exit(-1); 1691 } 1692 return (cp); 1693} 1694 1695char * 1696skip(cpp) 1697 char **cpp; 1698{ 1699 char *cp = *cpp; 1700 char *start; 1701 1702 if (*cpp == NULL) 1703 return ((char *)0); 1704 1705again: 1706 while (*cp == ' ' || *cp == '\t') 1707 cp++; 1708 if (*cp == '\0') { 1709 int c; 1710 1711 c = getc(fconfig); 1712 (void) ungetc(c, fconfig); 1713 if (c == ' ' || c == '\t') 1714 if ((cp = nextline(fconfig))) 1715 goto again; 1716 *cpp = (char *)0; 1717 return ((char *)0); 1718 } 1719 start = cp; 1720 while (*cp && *cp != ' ' && *cp != '\t') 1721 cp++; 1722 if (*cp != '\0') 1723 *cp++ = '\0'; 1724 *cpp = cp; 1725 return (start); 1726} 1727 1728char * 1729nextline(fd) 1730 FILE *fd; 1731{ 1732 char *cp; 1733 1734 if (fgets(line, sizeof (line), fd) == NULL) 1735 return ((char *)0); 1736 cp = strchr(line, '\n'); 1737 if (cp) 1738 *cp = '\0'; 1739 return (line); 1740} 1741 1742char * 1743newstr(cp) 1744 char *cp; 1745{ 1746 if ((cp = strdup(cp ? cp : ""))) 1747 return (cp); 1748 syslog(LOG_ERR, "strdup: %m"); 1749 exit(-1); 1750} 1751 1752void 1753inetd_setproctitle(a, s) 1754 char *a; 1755 int s; 1756{ 1757 int size; 1758 char *cp; 1759 struct sockaddr_storage ss; 1760 char buf[80]; 1761 char hbuf[80]; 1762 1763 cp = Argv[0]; 1764 size = sizeof(ss); 1765 if (getpeername(s, (struct sockaddr *)&ss, &size) == 0) { 1766 getnameinfo((struct sockaddr *)&ss, ss.ss_len, 1767 hbuf, sizeof(hbuf), NULL, 0, NI_NUMERICHOST); 1768 (void)snprintf(buf, sizeof buf, "-%s [%s]", a, hbuf); 1769 } else 1770 (void)snprintf(buf, sizeof buf, "-%s", a); 1771 strncpy(cp, buf, LastArg - cp); 1772 cp += strlen(cp); 1773 while (cp < LastArg) 1774 *cp++ = ' '; 1775} 1776 1777void 1778bump_nofile() 1779{ 1780#ifdef RLIMIT_NOFILE 1781 1782#define FD_CHUNK 32 1783 1784 struct rlimit rl; 1785 1786 if (getrlimit(RLIMIT_NOFILE, &rl) < 0) { 1787 syslog(LOG_ERR, "getrlimit: %m"); 1788 return; 1789 } 1790 rl.rlim_cur = MIN(rl.rlim_max, rl.rlim_cur + FD_CHUNK); 1791 if (rl.rlim_cur <= rlim_ofile_cur) { 1792 syslog(LOG_ERR, 1793 "bump_nofile: cannot extend file limit, max = %d", 1794 (int)rl.rlim_cur); 1795 return; 1796 } 1797 1798 if (setrlimit(RLIMIT_NOFILE, &rl) < 0) { 1799 syslog(LOG_ERR, "setrlimit: %m"); 1800 return; 1801 } 1802 1803 rlim_ofile_cur = rl.rlim_cur; 1804 return; 1805 1806#else 1807 syslog(LOG_ERR, "bump_nofile: cannot extend file limit"); 1808 return; 1809#endif 1810} 1811 1812/* 1813 * Internet services provided internally by inetd: 1814 */ 1815#define BUFSIZE 4096 1816 1817/* ARGSUSED */ 1818void 1819echo_stream(s, sep) /* Echo service -- echo data back */ 1820 int s; 1821 struct servtab *sep; 1822{ 1823 char buffer[BUFSIZE]; 1824 int i; 1825 1826 inetd_setproctitle(sep->se_service, s); 1827 while ((i = read(s, buffer, sizeof(buffer))) > 0 && 1828 write(s, buffer, i) > 0) 1829 ; 1830} 1831 1832/* ARGSUSED */ 1833void 1834echo_dg(s, sep) /* Echo service -- echo data back */ 1835 int s; 1836 struct servtab *sep; 1837{ 1838 char buffer[BUFSIZE]; 1839 int i, size; 1840 struct sockaddr sa; 1841 1842 size = sizeof(sa); 1843 if ((i = recvfrom(s, buffer, sizeof(buffer), 0, &sa, &size)) < 0) 1844 return; 1845 if (port_good_dg(&sa)) 1846 (void) sendto(s, buffer, i, 0, &sa, sizeof(sa)); 1847} 1848 1849/* ARGSUSED */ 1850void 1851discard_stream(s, sep) /* Discard service -- ignore data */ 1852 int s; 1853 struct servtab *sep; 1854{ 1855 char buffer[BUFSIZE]; 1856 1857 inetd_setproctitle(sep->se_service, s); 1858 while ((errno = 0, read(s, buffer, sizeof(buffer)) > 0) || 1859 errno == EINTR) 1860 ; 1861} 1862 1863/* ARGSUSED */ 1864void 1865discard_dg(s, sep) /* Discard service -- ignore data */ 1866 int s; 1867 struct servtab *sep; 1868{ 1869 char buffer[BUFSIZE]; 1870 1871 (void) read(s, buffer, sizeof(buffer)); 1872} 1873 1874#include <ctype.h> 1875#define LINESIZ 72 1876char ring[128]; 1877char *endring; 1878 1879void 1880initring() 1881{ 1882 int i; 1883 1884 endring = ring; 1885 1886 for (i = 0; i <= 128; ++i) 1887 if (isprint(i)) 1888 *endring++ = i; 1889} 1890 1891/* ARGSUSED */ 1892void 1893chargen_stream(s, sep) /* Character generator */ 1894 int s; 1895 struct servtab *sep; 1896{ 1897 int len; 1898 char *rs, text[LINESIZ+2]; 1899 1900 inetd_setproctitle(sep->se_service, s); 1901 1902 if (!endring) { 1903 initring(); 1904 rs = ring; 1905 } 1906 1907 text[LINESIZ] = '\r'; 1908 text[LINESIZ + 1] = '\n'; 1909 for (rs = ring;;) { 1910 if ((len = endring - rs) >= LINESIZ) 1911 memmove(text, rs, LINESIZ); 1912 else { 1913 memmove(text, rs, len); 1914 memmove(text + len, ring, LINESIZ - len); 1915 } 1916 if (++rs == endring) 1917 rs = ring; 1918 if (write(s, text, sizeof(text)) != sizeof(text)) 1919 break; 1920 } 1921} 1922 1923/* ARGSUSED */ 1924void 1925chargen_dg(s, sep) /* Character generator */ 1926 int s; 1927 struct servtab *sep; 1928{ 1929 struct sockaddr sa; 1930 static char *rs; 1931 int len, size; 1932 char text[LINESIZ+2]; 1933 1934 if (endring == 0) { 1935 initring(); 1936 rs = ring; 1937 } 1938 1939 size = sizeof(sa); 1940 if (recvfrom(s, text, sizeof(text), 0, &sa, &size) < 0) 1941 return; 1942 1943 if (!port_good_dg(&sa)) 1944 return; 1945 1946 if ((len = endring - rs) >= LINESIZ) 1947 memmove(text, rs, LINESIZ); 1948 else { 1949 memmove(text, rs, len); 1950 memmove(text + len, ring, LINESIZ - len); 1951 } 1952 if (++rs == endring) 1953 rs = ring; 1954 text[LINESIZ] = '\r'; 1955 text[LINESIZ + 1] = '\n'; 1956 (void) sendto(s, text, sizeof(text), 0, &sa, sizeof(sa)); 1957} 1958 1959/* 1960 * Return a machine readable date and time, in the form of the 1961 * number of seconds since midnight, Jan 1, 1900. Since gettimeofday 1962 * returns the number of seconds since midnight, Jan 1, 1970, 1963 * we must add 2208988800 seconds to this figure to make up for 1964 * some seventy years Bell Labs was asleep. 1965 */ 1966 1967long 1968machtime() 1969{ 1970 struct timeval tv; 1971 1972 if (gettimeofday(&tv, (struct timezone *)0) < 0) { 1973 if (debug) 1974 fprintf(stderr, "Unable to get time of day\n"); 1975 return (0L); 1976 } 1977#define OFFSET ((u_long)25567 * 24*60*60) 1978 return (htonl((long)(tv.tv_sec + OFFSET))); 1979#undef OFFSET 1980} 1981 1982/* ARGSUSED */ 1983void 1984machtime_stream(s, sep) 1985 int s; 1986 struct servtab *sep; 1987{ 1988 long result; 1989 1990 result = machtime(); 1991 (void) write(s, (char *) &result, sizeof(result)); 1992} 1993 1994/* ARGSUSED */ 1995void 1996machtime_dg(s, sep) 1997 int s; 1998 struct servtab *sep; 1999{ 2000 long result; 2001 struct sockaddr sa; 2002 int size; 2003 2004 size = sizeof(sa); 2005 if (recvfrom(s, (char *)&result, sizeof(result), 0, &sa, &size) < 0) 2006 return; 2007 if (!port_good_dg(&sa)) 2008 return; 2009 result = machtime(); 2010 (void) sendto(s, (char *) &result, sizeof(result), 0, &sa, sizeof(sa)); 2011} 2012 2013/* ARGSUSED */ 2014void 2015daytime_stream(s, sep) /* Return human-readable time of day */ 2016 int s; 2017 struct servtab *sep; 2018{ 2019 char buffer[256]; 2020 time_t clock; 2021 int len; 2022 2023 clock = time((time_t *) 0); 2024 2025 len = snprintf(buffer, sizeof buffer, "%.24s\r\n", ctime(&clock)); 2026 (void) write(s, buffer, len); 2027} 2028 2029/* ARGSUSED */ 2030void 2031daytime_dg(s, sep) /* Return human-readable time of day */ 2032 int s; 2033 struct servtab *sep; 2034{ 2035 char buffer[256]; 2036 time_t clock; 2037 struct sockaddr sa; 2038 int size, len; 2039 2040 clock = time((time_t *) 0); 2041 2042 size = sizeof(sa); 2043 if (recvfrom(s, buffer, sizeof(buffer), 0, &sa, &size) < 0) 2044 return; 2045 if (!port_good_dg(&sa)) 2046 return; 2047 len = snprintf(buffer, sizeof buffer, "%.24s\r\n", ctime(&clock)); 2048 (void) sendto(s, buffer, len, 0, &sa, sizeof(sa)); 2049} 2050 2051/* 2052 * print_service: 2053 * Dump relevant information to stderr 2054 */ 2055void 2056print_service(action, sep) 2057 char *action; 2058 struct servtab *sep; 2059{ 2060 if (isrpcservice(sep)) 2061 fprintf(stderr, 2062 "%s: %s rpcprog=%d, rpcvers = %d/%d, proto=%s, wait.max=%d.%d, user.group=%s.%s builtin=%lx server=%s" 2063#ifdef IPSEC 2064 " policy=\"%s\"" 2065#endif 2066 "\n", 2067 action, sep->se_service, 2068 sep->se_rpcprog, sep->se_rpcversh, sep->se_rpcversl, sep->se_proto, 2069 sep->se_wait, sep->se_max, sep->se_user, sep->se_group, 2070 (long)sep->se_bi, sep->se_server 2071#ifdef IPSEC 2072 , (sep->se_policy ? sep->se_policy : "") 2073#endif 2074 ); 2075 else 2076 fprintf(stderr, 2077 "%s: %s proto=%s, wait.max=%d.%d, user.group=%s.%s builtin=%lx server=%s" 2078#ifdef IPSEC 2079 " policy=%s" 2080#endif 2081 "\n", 2082 action, sep->se_service, sep->se_proto, 2083 sep->se_wait, sep->se_max, sep->se_user, sep->se_group, 2084 (long)sep->se_bi, sep->se_server 2085#ifdef IPSEC 2086 , (sep->se_policy ? sep->se_policy : "") 2087#endif 2088 ); 2089} 2090 2091void 2092usage() 2093{ 2094 2095#ifdef LIBWRAP 2096 (void)fprintf(stderr, "usage: %s [-dl] [conf]\n", __progname); 2097#else 2098 (void)fprintf(stderr, "usage: %s [-d] [conf]\n", __progname); 2099#endif 2100 exit(1); 2101} 2102 2103 2104/* 2105 * Based on TCPMUX.C by Mark K. Lottor November 1988 2106 * sri-nic::ps:<mkl>tcpmux.c 2107 */ 2108 2109static int /* # of characters upto \r,\n or \0 */ 2110getline(fd, buf, len) 2111 int fd; 2112 char *buf; 2113 int len; 2114{ 2115 int count = 0, n; 2116 2117 do { 2118 n = read(fd, buf, len-count); 2119 if (n == 0) 2120 return (count); 2121 if (n < 0) 2122 return (-1); 2123 while (--n >= 0) { 2124 if (*buf == '\r' || *buf == '\n' || *buf == '\0') 2125 return (count); 2126 count++; 2127 buf++; 2128 } 2129 } while (count < len); 2130 return (count); 2131} 2132 2133#define MAX_SERV_LEN (256+2) /* 2 bytes for \r\n */ 2134 2135#define strwrite(fd, buf) (void) write(fd, buf, sizeof(buf)-1) 2136 2137void 2138tcpmux(ctrl, sep) 2139 int ctrl; 2140 struct servtab *sep; 2141{ 2142 char service[MAX_SERV_LEN+1]; 2143 int len; 2144 2145 /* Get requested service name */ 2146 if ((len = getline(ctrl, service, MAX_SERV_LEN)) < 0) { 2147 strwrite(ctrl, "-Error reading service name\r\n"); 2148 goto reject; 2149 } 2150 service[len] = '\0'; 2151 2152 if (debug) 2153 fprintf(stderr, "tcpmux: someone wants %s\n", service); 2154 2155 /* 2156 * Help is a required command, and lists available services, 2157 * one per line. 2158 */ 2159 if (!strcasecmp(service, "help")) { 2160 strwrite(ctrl, "+Available services:\r\n"); 2161 strwrite(ctrl, "help\r\n"); 2162 for (sep = servtab; sep; sep = sep->se_next) { 2163 if (!ISMUX(sep)) 2164 continue; 2165 (void)write(ctrl, sep->se_service, 2166 strlen(sep->se_service)); 2167 strwrite(ctrl, "\r\n"); 2168 } 2169 goto reject; 2170 } 2171 2172 /* Try matching a service in inetd.conf with the request */ 2173 for (sep = servtab; sep; sep = sep->se_next) { 2174 if (!ISMUX(sep)) 2175 continue; 2176 if (!strcasecmp(service, sep->se_service)) { 2177 if (ISMUXPLUS(sep)) 2178 strwrite(ctrl, "+Go\r\n"); 2179 run_service(ctrl, sep); 2180 return; 2181 } 2182 } 2183 strwrite(ctrl, "-Service not available\r\n"); 2184reject: 2185 _exit(1); 2186} 2187 2188 2189#ifdef MULOG 2190dolog(sep, ctrl) 2191 struct servtab *sep; 2192 int ctrl; 2193{ 2194 struct sockaddr_storage ss; 2195 struct sockaddr *sa = (struct sockaddr *)ss; 2196 struct sockaddr_in *sin = (struct sockaddr_in *)&ss; 2197 int len = sizeof(ss); 2198 struct hostent *hp; 2199 char *host, *dp, buf[BUFSIZ], *rfc931_name(); 2200 int connected = 1; 2201 2202 switch (sep->se_family) { 2203 case AF_INET: 2204 case AF_INET6: 2205 break; 2206 default; 2207 return; 2208 } 2209 2210 if (getpeername(ctrl, sa, &len) < 0) { 2211 if (errno != ENOTCONN) { 2212 syslog(LOG_ERR, "getpeername: %m"); 2213 return; 2214 } 2215 if (recvfrom(ctrl, buf, sizeof(buf), MSG_PEEK, sa, &len) < 0) { 2216 syslog(LOG_ERR, "recvfrom: %m"); 2217 return; 2218 } 2219 connected = 0; 2220 } 2221 switch (sa->sa_family) { 2222 case AF_INET: 2223 case AF_INET6: 2224 break; 2225 default; 2226 syslog(LOG_ERR, "unexpected address family %u", sa->sa_family); 2227 return; 2228 } 2229 2230 getnameinfo(sa, sa->sa_len, buf, sizeof(buf), NULL, 0, 0); 2231 host = buf; 2232 2233 switch (sep->se_log & ~MULOG_RFC931) { 2234 case 0: 2235 return; 2236 case 1: 2237 if (curdom == NULL || *curdom == '\0') 2238 break; 2239 dp = host + strlen(host) - strlen(curdom); 2240 if (dp < host) 2241 break; 2242 if (debug) 2243 fprintf(stderr, "check \"%s\" against curdom \"%s\"\n", 2244 host, curdom); 2245 if (strcasecmp(dp, curdom) == 0) 2246 return; 2247 break; 2248 case 2: 2249 default: 2250 break; 2251 } 2252 2253 openlog("", LOG_NOWAIT, MULOG); 2254 2255 if (connected && (sep->se_log & MULOG_RFC931)) 2256 syslog(LOG_INFO, "%s@%s wants %s", 2257 rfc931_name(sa, ctrl), host, sep->se_service); 2258 else 2259 syslog(LOG_INFO, "%s wants %s", 2260 host, sep->se_service); 2261} 2262 2263/* 2264 * From tcp_log by 2265 * Wietse Venema, Eindhoven University of Technology, The Netherlands. 2266 */ 2267#if 0 2268static char sccsid[] = "@(#) rfc931.c 1.3 92/08/31 22:54:46"; 2269#endif 2270 2271#include <setjmp.h> 2272 2273#define RFC931_PORT 113 /* Semi-well-known port */ 2274#define TIMEOUT 4 2275#define TIMEOUT2 10 2276 2277static jmp_buf timebuf; 2278 2279/* timeout - handle timeouts */ 2280 2281static void timeout(sig) 2282int sig; 2283{ 2284 longjmp(timebuf, sig); 2285} 2286 2287/* rfc931_name - return remote user name */ 2288 2289char * 2290rfc931_name(there, ctrl) 2291struct sockaddr *there; /* remote link information */ 2292int ctrl; 2293{ 2294 struct sockaddr_storage here; /* local link information */ 2295 struct sockaddr_storage sin; /* for talking to RFC931 daemon */ 2296 int length; 2297 int s; 2298 unsigned remote; 2299 unsigned local; 2300 static char user[256]; /* XXX */ 2301 char buf[256]; 2302 char *cp; 2303 char *result = "USER_UNKNOWN"; 2304 int len; 2305 u_int16_t myport, hisport; 2306 2307 /* Find out local port number of our stdin. */ 2308 2309 length = sizeof(here); 2310 if (getsockname(ctrl, (struct sockaddr *) &here, &length) == -1) { 2311 syslog(LOG_ERR, "getsockname: %m"); 2312 return (result); 2313 } 2314 switch (here.ss_family) { 2315 case AF_INET: 2316 myport = ((struct sockaddr_in *)&here)->sin_port; 2317 break; 2318 case AF_INET6: 2319 myport = ((struct sockaddr_in6 *)&here)->sin6_port; 2320 break; 2321 } 2322 switch (there->sa_family) { 2323 case AF_INET: 2324 hisport = ((struct sockaddr_in *)sa)->sin_port; 2325 break; 2326 case AF_INET6: 2327 hisport = ((struct sockaddr_in6 *)sa)->sin6_port; 2328 break; 2329 } 2330 /* Set up timer so we won't get stuck. */ 2331 2332 if ((s = socket(here.ss_family, SOCK_STREAM, 0)) == -1) { 2333 syslog(LOG_ERR, "socket: %m"); 2334 return (result); 2335 } 2336 2337 sin = here; 2338 switch (sin.ss_family) { 2339 case AF_INET: 2340 ((struct sockaddr_in *)&sin)->sin_port = htons(0); 2341 break; 2342 case AF_INET6: 2343 ((struct sockaddr_in6 *)&sin)->sin6_port = htons(0); 2344 break; 2345 } 2346 if (bind(s, (struct sockaddr *) &sin, sin.ss_len) == -1) { 2347 syslog(LOG_ERR, "bind: %m"); 2348 return (result); 2349 } 2350 2351 signal(SIGALRM, timeout); 2352 if (setjmp(timebuf)) { 2353 close(s); /* not: fclose(fp) */ 2354 return (result); 2355 } 2356 alarm(TIMEOUT); 2357 2358 /* Connect to the RFC931 daemon. */ 2359 2360 memcpy(&sin, there, there->sa_len); 2361 switch (sin.ss_family) { 2362 case AF_INET: 2363 ((struct sockaddr_in *)&sin)->sin_port = htons(RFC931_PORT); 2364 break; 2365 case AF_INET6: 2366 ((struct sockaddr_in6 *)&sin)->sin6_port = htons(RFC931_PORT); 2367 break; 2368 } 2369 if (connect(s, (struct sockaddr *) &sin, sin.ss_len) == -1) { 2370 close(s); 2371 alarm(0); 2372 return (result); 2373 } 2374 2375 /* Query the RFC 931 server. Would 13-byte writes ever be broken up? */ 2376 (void)snprintf(buf, sizeof buf, "%u,%u\r\n", ntohs(hisport), 2377 ntohs(myport)); 2378 2379 2380 for (len = 0, cp = buf; len < strlen(buf); ) { 2381 int n; 2382 2383 if ((n = write(s, cp, strlen(buf) - len)) == -1) { 2384 close(s); 2385 alarm(0); 2386 return (result); 2387 } 2388 cp += n; 2389 len += n; 2390 } 2391 2392 /* Read response */ 2393 for (cp = buf; cp < buf + sizeof(buf) - 1; ) { 2394 char c; 2395 if (read(s, &c, 1) != 1) { 2396 close(s); 2397 alarm(0); 2398 return (result); 2399 } 2400 if (c == '\n') 2401 break; 2402 *cp++ = c; 2403 } 2404 *cp = '\0'; 2405 2406 if (sscanf(buf, "%u , %u : USERID :%*[^:]:%255s", &remote, &local, user) == 3 2407 && ntohs(hisport) == remote 2408 && ntohs(myport) == local) { 2409 2410 /* Strip trailing carriage return. */ 2411 if (cp = strchr(user, '\r')) 2412 *cp = 0; 2413 result = user; 2414 } 2415 2416 alarm(0); 2417 close(s); 2418 return (result); 2419} 2420#endif 2421 2422/* 2423 * check if the port where send data to is one of the obvious ports 2424 * that are used for denial of service attacks like two echo ports 2425 * just echoing data between them 2426 */ 2427int port_good_dg(struct sockaddr *sa) 2428{ 2429 struct sockaddr_in *sin; 2430 u_int16_t port; 2431 int i,bad; 2432 2433 bad=0; 2434 2435 sin=(struct sockaddr_in *)sa; 2436 port=ntohs(sin->sin_port); 2437 2438 for(i=0;bad_ports[i]!=0;i++) 2439 if (port==bad_ports[i]) { 2440 bad=1; 2441 break; 2442 } 2443 2444 if (bad) { 2445 syslog(LOG_WARNING,"Possible DoS attack from %s, Port %d", 2446 inet_ntoa(sin->sin_addr),port); 2447 return (0); 2448 } else 2449 return (1); 2450} 2451 2452