inetd.c revision 1.60
1/* $NetBSD: inetd.c,v 1.60 2000/05/13 02:56:47 itojun 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 1.60 2000/05/13 02:56:47 itojun 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#ifndef NO_RPC 211#define RPC 212#endif 213 214#include <netinet/in.h> 215#include <arpa/inet.h> 216#ifdef RPC 217#include <rpc/rpc.h> 218#include <rpc/pmap_clnt.h> 219#endif 220 221#include <ctype.h> 222#include <errno.h> 223#include <fcntl.h> 224#include <grp.h> 225#include <netdb.h> 226#include <pwd.h> 227#include <signal.h> 228#include <stdio.h> 229#include <stdlib.h> 230#include <string.h> 231#include <syslog.h> 232#include <unistd.h> 233#include <util.h> 234 235#include "pathnames.h" 236 237#ifdef IPSEC 238#include <netinet6/ipsec.h> 239#ifndef IPSEC_POLICY_IPSEC /* no ipsec support on old ipsec */ 240#undef IPSEC 241#endif 242#include "ipsec.h" 243#endif 244 245#ifdef LIBWRAP 246# include <tcpd.h> 247#ifndef LIBWRAP_ALLOW_FACILITY 248# define LIBWRAP_ALLOW_FACILITY LOG_AUTH 249#endif 250#ifndef LIBWRAP_ALLOW_SEVERITY 251# define LIBWRAP_ALLOW_SEVERITY LOG_INFO 252#endif 253#ifndef LIBWRAP_DENY_FACILITY 254# define LIBWRAP_DENY_FACILITY LOG_AUTH 255#endif 256#ifndef LIBWRAP_DENY_SEVERITY 257# define LIBWRAP_DENY_SEVERITY LOG_WARNING 258#endif 259int allow_severity = LIBWRAP_ALLOW_FACILITY|LIBWRAP_ALLOW_SEVERITY; 260int deny_severity = LIBWRAP_DENY_FACILITY|LIBWRAP_DENY_SEVERITY; 261#endif 262 263#define TOOMANY 40 /* don't start more than TOOMANY */ 264#define CNT_INTVL 60 /* servers in CNT_INTVL sec. */ 265#define RETRYTIME (60*10) /* retry after bind or server fail */ 266 267#define SIGBLOCK (sigmask(SIGCHLD)|sigmask(SIGHUP)|sigmask(SIGALRM)) 268 269int debug; 270#ifdef LIBWRAP 271int lflag; 272#endif 273int nsock, maxsock; 274fd_set allsock; 275int options; 276int timingout; 277struct servent *sp; 278char *curdom; 279#ifdef NI_WITHSCOPEID 280const int niflags = NI_NUMERICHOST | NI_NUMERICSERV | NI_WITHSCOPEID; 281#else 282const int niflags = NI_NUMERICHOST | NI_NUMERICSERV; 283#endif 284 285#ifndef OPEN_MAX 286#define OPEN_MAX 64 287#endif 288 289/* Reserve some descriptors, 3 stdio + at least: 1 log, 1 conf. file */ 290#define FD_MARGIN (8) 291typeof(((struct rlimit *)0)->rlim_cur) rlim_ofile_cur = OPEN_MAX; 292 293#ifdef RLIMIT_NOFILE 294struct rlimit rlim_ofile; 295#endif 296 297struct servtab { 298 char *se_hostaddr; /* host address to listen on */ 299 char *se_service; /* name of service */ 300 int se_socktype; /* type of socket to use */ 301 int se_family; /* address family */ 302 char *se_proto; /* protocol used */ 303 int se_sndbuf; /* sndbuf size */ 304 int se_rcvbuf; /* rcvbuf size */ 305 int se_rpcprog; /* rpc program number */ 306 int se_rpcversl; /* rpc program lowest version */ 307 int se_rpcversh; /* rpc program highest version */ 308#define isrpcservice(sep) ((sep)->se_rpcversl != 0) 309 pid_t se_wait; /* single threaded server */ 310 short se_checked; /* looked at during merge */ 311 char *se_user; /* user name to run as */ 312 char *se_group; /* group name to run as */ 313 struct biltin *se_bi; /* if built-in, description */ 314 char *se_server; /* server program */ 315#define MAXARGV 20 316 char *se_argv[MAXARGV+1]; /* program arguments */ 317#ifdef IPSEC 318 char *se_policy; /* IPsec poilcy string */ 319#endif 320 int se_fd; /* open descriptor */ 321 int se_type; /* type */ 322 union { 323 struct sockaddr se_un_ctrladdr; 324 struct sockaddr_in se_un_ctrladdr_in; 325 struct sockaddr_in6 se_un_ctrladdr_in6; 326 struct sockaddr_un se_un_ctrladdr_un; 327 } se_un; /* bound address */ 328#define se_ctrladdr se_un.se_un_ctrladdr 329#define se_ctrladdr_in se_un.se_un_ctrladdr_in 330#define se_ctrladdr_un se_un.se_un_ctrladdr_un 331 int se_ctrladdr_size; 332 int se_max; /* max # of instances of this service */ 333 int se_count; /* number started since se_time */ 334 struct timeval se_time; /* start of se_count */ 335#ifdef MULOG 336 int se_log; 337#define MULOG_RFC931 0x40000000 338#endif 339 struct servtab *se_next; 340} *servtab; 341 342#define NORM_TYPE 0 343#define MUX_TYPE 1 344#define MUXPLUS_TYPE 2 345#define ISMUX(sep) (((sep)->se_type == MUX_TYPE) || \ 346 ((sep)->se_type == MUXPLUS_TYPE)) 347#define ISMUXPLUS(sep) ((sep)->se_type == MUXPLUS_TYPE) 348 349 350void chargen_dg __P((int, struct servtab *)); 351void chargen_stream __P((int, struct servtab *)); 352void close_sep __P((struct servtab *)); 353void config __P((int)); 354void daytime_dg __P((int, struct servtab *)); 355void daytime_stream __P((int, struct servtab *)); 356void discard_dg __P((int, struct servtab *)); 357void discard_stream __P((int, struct servtab *)); 358void echo_dg __P((int, struct servtab *)); 359void echo_stream __P((int, struct servtab *)); 360void endconfig __P((void)); 361struct servtab *enter __P((struct servtab *)); 362void freeconfig __P((struct servtab *)); 363struct servtab *getconfigent __P((void)); 364void goaway __P((int)); 365void machtime_dg __P((int, struct servtab *)); 366void machtime_stream __P((int, struct servtab *)); 367char *newstr __P((char *)); 368char *nextline __P((FILE *)); 369void print_service __P((char *, struct servtab *)); 370void reapchild __P((int)); 371void retry __P((int)); 372void run_service __P((int, struct servtab *)); 373int setconfig __P((void)); 374void setup __P((struct servtab *)); 375char *sskip __P((char **)); 376char *skip __P((char **)); 377void tcpmux __P((int, struct servtab *)); 378void usage __P((void)); 379void register_rpc __P((struct servtab *sep)); 380void unregister_rpc __P((struct servtab *sep)); 381void bump_nofile __P((void)); 382void inetd_setproctitle __P((char *, int)); 383void initring __P((void)); 384long machtime __P((void)); 385int port_good_dg __P((struct sockaddr *sa)); 386static int getline __P((int, char *, int)); 387int main __P((int, char *[], char *[])); 388 389struct biltin { 390 char *bi_service; /* internally provided service name */ 391 int bi_socktype; /* type of socket supported */ 392 short bi_fork; /* 1 if should fork before call */ 393 short bi_wait; /* 1 if should wait for child */ 394 void (*bi_fn) __P((int, struct servtab *)); 395 /* function which performs it */ 396} biltins[] = { 397 /* Echo received data */ 398 { "echo", SOCK_STREAM, 1, 0, echo_stream }, 399 { "echo", SOCK_DGRAM, 0, 0, echo_dg }, 400 401 /* Internet /dev/null */ 402 { "discard", SOCK_STREAM, 1, 0, discard_stream }, 403 { "discard", SOCK_DGRAM, 0, 0, discard_dg }, 404 405 /* Return 32 bit time since 1970 */ 406 { "time", SOCK_STREAM, 0, 0, machtime_stream }, 407 { "time", SOCK_DGRAM, 0, 0, machtime_dg }, 408 409 /* Return human-readable time */ 410 { "daytime", SOCK_STREAM, 0, 0, daytime_stream }, 411 { "daytime", SOCK_DGRAM, 0, 0, daytime_dg }, 412 413 /* Familiar character generator */ 414 { "chargen", SOCK_STREAM, 1, 0, chargen_stream }, 415 { "chargen", SOCK_DGRAM, 0, 0, chargen_dg }, 416 417 { "tcpmux", SOCK_STREAM, 1, 0, tcpmux }, 418 419 { NULL } 420}; 421 422/* list of "bad" ports. I.e. ports that are most obviously used for 423 * "cycling packets" denial of service attacks. See /etc/services. 424 * List must end with port number "0". 425 */ 426 427u_int16_t bad_ports[] = { 7, 9, 13, 19, 37, 0}; 428 429 430#define NUMINT (sizeof(intab) / sizeof(struct inent)) 431char *CONFIG = _PATH_INETDCONF; 432char **Argv; 433char *LastArg; 434extern char *__progname; 435 436#ifdef sun 437/* 438 * Sun's RPC library caches the result of `dtablesize()' 439 * This is incompatible with our "bumping" of file descriptors "on demand" 440 */ 441int 442_rpc_dtablesize() 443{ 444 return rlim_ofile_cur; 445} 446#endif 447 448int 449main(argc, argv, envp) 450 int argc; 451 char *argv[], *envp[]; 452{ 453 struct servtab *sep, *nsep; 454 struct sigvec sv; 455 int ch, dofork; 456 pid_t pid; 457 458 Argv = argv; 459 if (envp == 0 || *envp == 0) 460 envp = argv; 461 while (*envp) 462 envp++; 463 LastArg = envp[-1] + strlen(envp[-1]); 464 465 while ((ch = getopt(argc, argv, 466#ifdef LIBWRAP 467 "dl" 468#else 469 "d" 470#endif 471 )) != -1) 472 switch(ch) { 473 case 'd': 474 debug = 1; 475 options |= SO_DEBUG; 476 break; 477#ifdef LIBWRAP 478 case 'l': 479 lflag = 1; 480 break; 481#endif 482 case '?': 483 default: 484 usage(); 485 } 486 argc -= optind; 487 argv += optind; 488 489 if (argc > 0) 490 CONFIG = argv[0]; 491 492 if (debug == 0) 493 daemon(0, 0); 494 openlog(__progname, LOG_PID | LOG_NOWAIT, LOG_DAEMON); 495 pidfile(NULL); 496 497#ifdef RLIMIT_NOFILE 498 if (getrlimit(RLIMIT_NOFILE, &rlim_ofile) < 0) { 499 syslog(LOG_ERR, "getrlimit: %m"); 500 } else { 501 rlim_ofile_cur = rlim_ofile.rlim_cur; 502 if (rlim_ofile_cur == RLIM_INFINITY) /* ! */ 503 rlim_ofile_cur = OPEN_MAX; 504 } 505#endif 506 507 memset(&sv, 0, sizeof(sv)); 508 sv.sv_mask = SIGBLOCK; 509 sv.sv_handler = retry; 510 sigvec(SIGALRM, &sv, (struct sigvec *)0); 511 config(SIGHUP); 512 sv.sv_handler = config; 513 sigvec(SIGHUP, &sv, (struct sigvec *)0); 514 sv.sv_handler = reapchild; 515 sigvec(SIGCHLD, &sv, (struct sigvec *)0); 516 sv.sv_handler = goaway; 517 sigvec(SIGTERM, &sv, (struct sigvec *)0); 518 sv.sv_handler = goaway; 519 sigvec(SIGINT, &sv, (struct sigvec *)0); 520 sv.sv_mask = 0L; 521 sv.sv_handler = SIG_IGN; 522 sigvec(SIGPIPE, &sv, (struct sigvec *)0); 523 524 { 525 /* space for daemons to overwrite environment for ps */ 526#define DUMMYSIZE 100 527 char dummy[DUMMYSIZE]; 528 529 (void)memset(dummy, 'x', DUMMYSIZE - 1); 530 dummy[DUMMYSIZE - 1] = '\0'; 531 532 (void)setenv("inetd_dummy", dummy, 1); 533 } 534 535 for (;;) { 536 int n, ctrl; 537 fd_set readable; 538 539 if (nsock == 0) { 540 (void) sigblock(SIGBLOCK); 541 while (nsock == 0) 542 sigpause(0L); 543 (void) sigsetmask(0L); 544 } 545 readable = allsock; 546 if ((n = select(maxsock + 1, &readable, (fd_set *)0, 547 (fd_set *)0, (struct timeval *)0)) <= 0) { 548 if (n == -1 && errno != EINTR) { 549 syslog(LOG_WARNING, "select: %m"); 550 sleep(1); 551 } 552 continue; 553 } 554 for (sep = servtab; n && sep; sep = nsep) { 555 nsep = sep->se_next; 556 if (sep->se_fd != -1 && FD_ISSET(sep->se_fd, &readable)) { 557 n--; 558 if (debug) 559 fprintf(stderr, "someone wants %s\n", sep->se_service); 560 if (!sep->se_wait && sep->se_socktype == SOCK_STREAM) { 561 /* XXX here do the libwrap check-before-accept */ 562 ctrl = accept(sep->se_fd, (struct sockaddr *)0, 563 (int *)0); 564 if (debug) 565 fprintf(stderr, "accept, ctrl %d\n", ctrl); 566 if (ctrl < 0) { 567 if (errno != EINTR) 568 syslog(LOG_WARNING, 569 "accept (for %s): %m", 570 sep->se_service); 571 continue; 572 } 573 } else 574 ctrl = sep->se_fd; 575 (void) sigblock(SIGBLOCK); 576 pid = 0; 577#ifdef LIBWRAP_INTERNAL 578 dofork = 1; 579#else 580 dofork = (sep->se_bi == 0 || sep->se_bi->bi_fork); 581#endif 582 if (dofork) { 583 if (sep->se_count++ == 0) 584 (void)gettimeofday(&sep->se_time, 585 (struct timezone *)0); 586 else if (sep->se_count >= sep->se_max) { 587 struct timeval now; 588 589 (void)gettimeofday(&now, (struct timezone *)0); 590 if (now.tv_sec - sep->se_time.tv_sec > 591 CNT_INTVL) { 592 sep->se_time = now; 593 sep->se_count = 1; 594 } else { 595 syslog(LOG_ERR, 596 "%s/%s server failing (looping), service terminated\n", 597 sep->se_service, sep->se_proto); 598 if (!sep->se_wait && sep->se_socktype == SOCK_STREAM) 599 close(ctrl); 600 close_sep(sep); 601 sigsetmask(0L); 602 if (!timingout) { 603 timingout = 1; 604 alarm(RETRYTIME); 605 } 606 continue; 607 } 608 } 609 pid = fork(); 610 if (pid < 0) { 611 syslog(LOG_ERR, "fork: %m"); 612 if (!sep->se_wait && sep->se_socktype == SOCK_STREAM) 613 close(ctrl); 614 sigsetmask(0L); 615 sleep(1); 616 continue; 617 } 618 if (pid != 0 && sep->se_wait) { 619 sep->se_wait = pid; 620 FD_CLR(sep->se_fd, &allsock); 621 nsock--; 622 } 623 if (pid == 0) { 624 sv.sv_mask = 0L; 625 sv.sv_handler = SIG_DFL; 626 sigvec(SIGPIPE, &sv, (struct sigvec *)0); 627 if (debug) 628 setsid(); 629 } 630 } 631 sigsetmask(0L); 632 if (pid == 0) { 633 run_service(ctrl, sep); 634 if (dofork) 635 exit(0); 636 } 637 if (!sep->se_wait && sep->se_socktype == SOCK_STREAM) 638 close(ctrl); 639 } 640 } 641 } 642} 643 644void 645run_service(ctrl, sep) 646 int ctrl; 647 struct servtab *sep; 648{ 649 struct passwd *pwd; 650 struct group *grp = NULL; /* XXX gcc */ 651 char buf[NI_MAXSERV]; 652#ifdef LIBWRAP 653 struct request_info req; 654 int denied; 655 char *service = NULL; /* XXX gcc */ 656#endif 657 658#ifdef LIBWRAP 659#ifndef LIBWRAP_INTERNAL 660 if (sep->se_bi == 0) 661#endif 662 if (!sep->se_wait && sep->se_socktype == SOCK_STREAM) { 663 request_init(&req, RQ_DAEMON, sep->se_argv[0] ? 664 sep->se_argv[0] : sep->se_service, RQ_FILE, ctrl, NULL); 665 fromhost(&req); 666 denied = !hosts_access(&req); 667 if (denied || lflag) { 668 if (getnameinfo(&sep->se_ctrladdr, 669 sep->se_ctrladdr.sa_len, NULL, 0, 670 buf, sizeof(buf), 0) != 0) { 671 /* shouldn't happen */ 672 (void)snprintf(buf, sizeof buf, "%d", 673 ntohs(sep->se_ctrladdr_in.sin_port)); 674 } 675 service = buf; 676 } 677 if (denied) { 678 syslog(deny_severity, 679 "refused connection from %.500s, service %s (%s)", 680 eval_client(&req), service, sep->se_proto); 681 goto reject; 682 } 683 if (lflag) { 684 syslog(allow_severity, 685 "connection from %.500s, service %s (%s)", 686 eval_client(&req), service, sep->se_proto); 687 } 688 } 689#endif /* LIBWRAP */ 690 691 if (sep->se_bi) { 692 (*sep->se_bi->bi_fn)(ctrl, sep); 693 } else { 694 if ((pwd = getpwnam(sep->se_user)) == NULL) { 695 syslog(LOG_ERR, "%s/%s: %s: No such user", 696 sep->se_service, sep->se_proto, sep->se_user); 697 goto reject; 698 } 699 if (sep->se_group && 700 (grp = getgrnam(sep->se_group)) == NULL) { 701 syslog(LOG_ERR, "%s/%s: %s: No such group", 702 sep->se_service, sep->se_proto, sep->se_group); 703 goto reject; 704 } 705 if (pwd->pw_uid) { 706 if (sep->se_group) 707 pwd->pw_gid = grp->gr_gid; 708 if (setgid(pwd->pw_gid) < 0) { 709 syslog(LOG_ERR, 710 "%s/%s: can't set gid %d: %m", sep->se_service, 711 sep->se_proto, pwd->pw_gid); 712 goto reject; 713 } 714 (void) initgroups(pwd->pw_name, 715 pwd->pw_gid); 716 if (setuid(pwd->pw_uid) < 0) { 717 syslog(LOG_ERR, 718 "%s/%s: can't set uid %d: %m", sep->se_service, 719 sep->se_proto, pwd->pw_uid); 720 goto reject; 721 } 722 } else if (sep->se_group) { 723 (void) setgid((gid_t)grp->gr_gid); 724 } 725 if (debug) 726 fprintf(stderr, "%d execl %s\n", 727 getpid(), sep->se_server); 728#ifdef MULOG 729 if (sep->se_log) 730 dolog(sep, ctrl); 731#endif 732 /* Set our control descriptor to not close-on-exec... */ 733 if (fcntl(ctrl, F_SETFD, 0) < 0) 734 syslog(LOG_ERR, "fcntl (F_SETFD, 0): %m"); 735 /* ...and dup it to stdin, stdout, and stderr. */ 736 if (ctrl != 0) { 737 dup2(ctrl, 0); 738 close(ctrl); 739 ctrl = 0; 740 } 741 dup2(0, 1); 742 dup2(0, 2); 743#ifdef RLIMIT_NOFILE 744 if (rlim_ofile.rlim_cur != rlim_ofile_cur && 745 setrlimit(RLIMIT_NOFILE, &rlim_ofile) < 0) 746 syslog(LOG_ERR, "setrlimit: %m"); 747#endif 748 execv(sep->se_server, sep->se_argv); 749 syslog(LOG_ERR, "cannot execute %s: %m", sep->se_server); 750 reject: 751 if (sep->se_socktype != SOCK_STREAM) 752 recv(ctrl, buf, sizeof (buf), 0); 753 _exit(1); 754 } 755} 756 757void 758reapchild(signo) 759 int signo; 760{ 761 int status; 762 pid_t pid; 763 struct servtab *sep; 764 765 for (;;) { 766 pid = wait3(&status, WNOHANG, (struct rusage *)0); 767 if (pid <= 0) 768 break; 769 if (debug) 770 fprintf(stderr, "%d reaped, status %#x\n", 771 pid, status); 772 for (sep = servtab; sep; sep = sep->se_next) 773 if (sep->se_wait == pid) { 774 if (WIFEXITED(status) && WEXITSTATUS(status)) 775 syslog(LOG_WARNING, 776 "%s: exit status 0x%x", 777 sep->se_server, WEXITSTATUS(status)); 778 else if (WIFSIGNALED(status)) 779 syslog(LOG_WARNING, 780 "%s: exit signal 0x%x", 781 sep->se_server, WTERMSIG(status)); 782 sep->se_wait = 1; 783 FD_SET(sep->se_fd, &allsock); 784 nsock++; 785 if (debug) 786 fprintf(stderr, "restored %s, fd %d\n", 787 sep->se_service, sep->se_fd); 788 } 789 } 790} 791 792void 793config(signo) 794 int signo; 795{ 796 struct servtab *sep, *cp, **sepp; 797 long omask; 798 int n; 799 800 if (!setconfig()) { 801 syslog(LOG_ERR, "%s: %m", CONFIG); 802 return; 803 } 804 for (sep = servtab; sep; sep = sep->se_next) 805 sep->se_checked = 0; 806 while ((cp = getconfigent())) { 807 for (sep = servtab; sep; sep = sep->se_next) 808 if (strcmp(sep->se_service, cp->se_service) == 0 && 809 strcmp(sep->se_hostaddr, cp->se_hostaddr) == 0 && 810 strcmp(sep->se_proto, cp->se_proto) == 0 && 811 ISMUX(sep) == ISMUX(cp)) 812 break; 813 if (sep != 0) { 814 int i; 815 816#define SWAP(type, a, b) {type c=(type)a; (type)a=(type)b; (type)b=(type)c;} 817 818 omask = sigblock(SIGBLOCK); 819 /* 820 * sep->se_wait may be holding the pid of a daemon 821 * that we're waiting for. If so, don't overwrite 822 * it unless the config file explicitly says don't 823 * wait. 824 */ 825 if (cp->se_bi == 0 && 826 (sep->se_wait == 1 || cp->se_wait == 0)) 827 sep->se_wait = cp->se_wait; 828 SWAP(char *, sep->se_user, cp->se_user); 829 SWAP(char *, sep->se_group, cp->se_group); 830 SWAP(char *, sep->se_server, cp->se_server); 831 for (i = 0; i < MAXARGV; i++) 832 SWAP(char *, sep->se_argv[i], cp->se_argv[i]); 833#ifdef IPSEC 834 SWAP(char *, sep->se_policy, cp->se_policy); 835 if (sep->se_fd != -1) { 836 if (ipsecsetup(sep->se_family, sep->se_fd, 837 sep->se_policy) < 0 && sep->se_policy) { 838 syslog(LOG_ERR, "%s/%s: " 839 "ipsec initialization failed", 840 sep->se_service, sep->se_proto); 841 sep->se_checked = 0; 842 sigsetmask(omask); 843 continue; 844 } 845 } 846#endif 847 SWAP(int, cp->se_type, sep->se_type); 848 SWAP(int, cp->se_max, sep->se_max); 849#undef SWAP 850 if (isrpcservice(sep)) 851 unregister_rpc(sep); 852 sep->se_rpcversl = cp->se_rpcversl; 853 sep->se_rpcversh = cp->se_rpcversh; 854 sigsetmask(omask); 855 freeconfig(cp); 856 if (debug) 857 print_service("REDO", sep); 858 } else { 859 sep = enter(cp); 860 if (debug) 861 print_service("ADD ", sep); 862 } 863 sep->se_checked = 1; 864 865 switch (sep->se_family) { 866 case AF_LOCAL: 867 if (sep->se_fd != -1) 868 break; 869 n = strlen(sep->se_service); 870 if (n > sizeof(sep->se_ctrladdr_un.sun_path)) { 871 syslog(LOG_ERR, "%s: address too long", 872 sep->se_service); 873 sep->se_checked = 0; 874 continue; 875 } 876 (void)unlink(sep->se_service); 877 strncpy(sep->se_ctrladdr_un.sun_path, 878 sep->se_service, n); 879 sep->se_ctrladdr_un.sun_family = AF_LOCAL; 880 sep->se_ctrladdr_size = n + 881 sizeof(sep->se_ctrladdr_un) - 882 sizeof(sep->se_ctrladdr_un.sun_path); 883 if (!ISMUX(sep)) 884 setup(sep); 885 break; 886 case AF_INET: 887#ifdef INET6 888 case AF_INET6: 889#endif 890 { 891 struct addrinfo hints, *res; 892 char *host, *port; 893 int error; 894 895 memset(&hints, 0, sizeof(hints)); 896 hints.ai_family = sep->se_family; 897 hints.ai_socktype = sep->se_socktype; 898 if (!strcmp(sep->se_hostaddr, "*")) { 899 hints.ai_flags = AI_PASSIVE; 900 host = NULL; 901 } else 902 host = sep->se_hostaddr; 903 if (isrpcservice(sep) || ISMUX(sep)) 904 port = "0"; 905 else 906 port = sep->se_service; 907 error = getaddrinfo(host, port, &hints, &res); 908 if (error) { 909 if (host == NULL) { 910 syslog(LOG_ERR, "%s/%s: %s: " 911 "the address family is not " 912 "supported by the kernel", 913 sep->se_service, sep->se_proto, 914 sep->se_hostaddr); 915 } else { 916 syslog(LOG_ERR, "%s/%s: %s: %s", 917 sep->se_service, sep->se_proto, 918 sep->se_hostaddr, 919 gai_strerror(error)); 920 } 921 sep->se_checked = 0; 922 continue; 923 } 924 if (res->ai_next) { 925 syslog(LOG_ERR, 926 "%s/%s: %s: resolved to multiple addr", 927 sep->se_service, sep->se_proto, 928 sep->se_hostaddr); 929 sep->se_checked = 0; 930 freeaddrinfo(res); 931 continue; 932 } 933 memcpy(&sep->se_ctrladdr, res->ai_addr, 934 res->ai_addrlen); 935 if (ISMUX(sep)) { 936 sep->se_fd = -1; 937 freeaddrinfo(res); 938 continue; 939 } 940 sep->se_ctrladdr_size = res->ai_addrlen; 941 freeaddrinfo(res); 942#ifdef RPC 943 if (isrpcservice(sep)) { 944 struct rpcent *rp; 945 946 sep->se_rpcprog = atoi(sep->se_service); 947 if (sep->se_rpcprog == 0) { 948 rp = getrpcbyname(sep->se_service); 949 if (rp == 0) { 950 syslog(LOG_ERR, 951 "%s/%s: unknown service", 952 sep->se_service, 953 sep->se_proto); 954 sep->se_checked = 0; 955 continue; 956 } 957 sep->se_rpcprog = rp->r_number; 958 } 959 if (sep->se_fd == -1 && !ISMUX(sep)) 960 setup(sep); 961 if (sep->se_fd != -1) 962 register_rpc(sep); 963 } else 964#endif 965 { 966 if (sep->se_fd >= 0) 967 close_sep(sep); 968 if (sep->se_fd == -1 && !ISMUX(sep)) 969 setup(sep); 970 } 971 } 972 } 973 } 974 endconfig(); 975 /* 976 * Purge anything not looked at above. 977 */ 978 omask = sigblock(SIGBLOCK); 979 sepp = &servtab; 980 while ((sep = *sepp)) { 981 if (sep->se_checked) { 982 sepp = &sep->se_next; 983 continue; 984 } 985 *sepp = sep->se_next; 986 if (sep->se_fd >= 0) 987 close_sep(sep); 988 if (isrpcservice(sep)) 989 unregister_rpc(sep); 990 if (sep->se_family == AF_LOCAL) 991 (void)unlink(sep->se_service); 992 if (debug) 993 print_service("FREE", sep); 994 freeconfig(sep); 995 free((char *)sep); 996 } 997 (void) sigsetmask(omask); 998} 999 1000void 1001retry(signo) 1002 int signo; 1003{ 1004 struct servtab *sep; 1005 1006 timingout = 0; 1007 for (sep = servtab; sep; sep = sep->se_next) { 1008 if (sep->se_fd == -1 && !ISMUX(sep)) { 1009 switch (sep->se_family) { 1010 case AF_LOCAL: 1011 case AF_INET: 1012#ifdef INET6 1013 case AF_INET6: 1014#endif 1015 setup(sep); 1016 if (sep->se_fd != -1 && isrpcservice(sep)) 1017 register_rpc(sep); 1018 break; 1019 } 1020 } 1021 } 1022} 1023 1024void 1025goaway(signo) 1026 int signo; 1027{ 1028 struct servtab *sep; 1029 1030 for (sep = servtab; sep; 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 1051void 1052setup(sep) 1053 struct servtab *sep; 1054{ 1055 int on = 1; 1056 1057 if ((sep->se_fd = socket(sep->se_family, sep->se_socktype, 0)) < 0) { 1058 if (debug) 1059 fprintf(stderr, "socket failed on %s/%s: %s\n", 1060 sep->se_service, sep->se_proto, strerror(errno)); 1061 syslog(LOG_ERR, "%s/%s: socket: %m", 1062 sep->se_service, sep->se_proto); 1063 return; 1064 } 1065 /* Set all listening sockets to close-on-exec. */ 1066 if (fcntl(sep->se_fd, F_SETFD, FD_CLOEXEC) < 0) 1067 syslog(LOG_ERR, "fcntl (F_SETFD, FD_CLOEXEC): %m"); 1068 1069#define turnon(fd, opt) \ 1070setsockopt(fd, SOL_SOCKET, opt, (char *)&on, sizeof (on)) 1071 if (strcmp(sep->se_proto, "tcp") == 0 && (options & SO_DEBUG) && 1072 turnon(sep->se_fd, SO_DEBUG) < 0) 1073 syslog(LOG_ERR, "setsockopt (SO_DEBUG): %m"); 1074 if (turnon(sep->se_fd, SO_REUSEADDR) < 0) 1075 syslog(LOG_ERR, "setsockopt (SO_REUSEADDR): %m"); 1076#undef turnon 1077 1078 /* Set the socket buffer sizes, if specified. */ 1079 if (sep->se_sndbuf != 0 && setsockopt(sep->se_fd, SOL_SOCKET, 1080 SO_SNDBUF, (char *)&sep->se_sndbuf, sizeof(sep->se_sndbuf)) < 0) 1081 syslog(LOG_ERR, "setsockopt (SO_SNDBUF %d): %m", 1082 sep->se_sndbuf); 1083 if (sep->se_rcvbuf != 0 && setsockopt(sep->se_fd, SOL_SOCKET, 1084 SO_RCVBUF, (char *)&sep->se_rcvbuf, sizeof(sep->se_rcvbuf)) < 0) 1085 syslog(LOG_ERR, "setsockopt (SO_RCVBUF %d): %m", 1086 sep->se_rcvbuf); 1087#ifdef IPSEC 1088 if (ipsecsetup(sep->se_family, sep->se_fd, sep->se_policy) < 0 1089 && sep->se_policy) { 1090 syslog(LOG_ERR, "%s/%s: ipsec setup failed", 1091 sep->se_service, sep->se_proto); 1092 (void)close(sep->se_fd); 1093 sep->se_fd = -1; 1094 return; 1095 } 1096#endif 1097 1098 if (bind(sep->se_fd, &sep->se_ctrladdr, sep->se_ctrladdr_size) < 0) { 1099 if (debug) 1100 fprintf(stderr, "bind failed on %s/%s: %s\n", 1101 sep->se_service, sep->se_proto, strerror(errno)); 1102 syslog(LOG_ERR, "%s/%s: bind: %m", 1103 sep->se_service, sep->se_proto); 1104 (void) close(sep->se_fd); 1105 sep->se_fd = -1; 1106 if (!timingout) { 1107 timingout = 1; 1108 alarm(RETRYTIME); 1109 } 1110 return; 1111 } 1112 if (sep->se_socktype == SOCK_STREAM) 1113 listen(sep->se_fd, 10); 1114 1115 FD_SET(sep->se_fd, &allsock); 1116 nsock++; 1117 if (sep->se_fd > maxsock) { 1118 maxsock = sep->se_fd; 1119 if (maxsock > rlim_ofile_cur - FD_MARGIN) 1120 bump_nofile(); 1121 } 1122 if (debug) 1123 fprintf(stderr, "registered %s on %d\n", 1124 sep->se_server, sep->se_fd); 1125} 1126 1127/* 1128 * Finish with a service and its socket. 1129 */ 1130void 1131close_sep(sep) 1132 struct servtab *sep; 1133{ 1134 if (sep->se_fd >= 0) { 1135 nsock--; 1136 FD_CLR(sep->se_fd, &allsock); 1137 (void) close(sep->se_fd); 1138 sep->se_fd = -1; 1139 } 1140 sep->se_count = 0; 1141 /* 1142 * Don't keep the pid of this running deamon: when reapchild() 1143 * reaps this pid, it would erroneously increment nsock. 1144 */ 1145 if (sep->se_wait > 1) 1146 sep->se_wait = 1; 1147} 1148 1149void 1150register_rpc(sep) 1151 struct servtab *sep; 1152{ 1153#ifdef RPC 1154 int n; 1155 struct sockaddr_storage ss; 1156 struct sockaddr_in *sin = (struct sockaddr_in *)&ss; 1157 struct protoent *pp; 1158 1159 if ((pp = getprotobyname(sep->se_proto+4)) == NULL) { 1160 syslog(LOG_ERR, "%s: getproto: %m", 1161 sep->se_proto); 1162 return; 1163 } 1164 n = sizeof ss; 1165 if (getsockname(sep->se_fd, (struct sockaddr *)&ss, &n) < 0) { 1166 syslog(LOG_ERR, "%s/%s: getsockname: %m", 1167 sep->se_service, sep->se_proto); 1168 return; 1169 } 1170 if (ss.ss_family != AF_INET) { /*XXX*/ 1171 syslog(LOG_ERR, "%s/%s: rpc not supported", 1172 sep->se_service, sep->se_proto); 1173 return; 1174 } 1175 1176 for (n = sep->se_rpcversl; n <= sep->se_rpcversh; n++) { 1177 if (debug) 1178 fprintf(stderr, "pmap_set: %u %u %u %u\n", 1179 sep->se_rpcprog, n, pp->p_proto, 1180 ntohs(sin->sin_port)); 1181 (void)pmap_unset(sep->se_rpcprog, n); 1182 if (!pmap_set(sep->se_rpcprog, n, pp->p_proto, ntohs(sin->sin_port))) 1183 syslog(LOG_ERR, "pmap_set: %u %u %u %u: %m", 1184 sep->se_rpcprog, n, pp->p_proto, 1185 ntohs(sin->sin_port)); 1186 } 1187#endif /* RPC */ 1188} 1189 1190void 1191unregister_rpc(sep) 1192 struct servtab *sep; 1193{ 1194#ifdef RPC 1195 int n; 1196 1197 for (n = sep->se_rpcversl; n <= sep->se_rpcversh; n++) { 1198 if (debug) 1199 fprintf(stderr, "pmap_unset(%u, %u)\n", 1200 sep->se_rpcprog, n); 1201 if (!pmap_unset(sep->se_rpcprog, n)) 1202 syslog(LOG_ERR, "pmap_unset(%u, %u)\n", 1203 sep->se_rpcprog, n); 1204 } 1205#endif /* RPC */ 1206} 1207 1208 1209struct servtab * 1210enter(cp) 1211 struct servtab *cp; 1212{ 1213 struct servtab *sep; 1214 long omask; 1215 1216 sep = (struct servtab *)malloc(sizeof (*sep)); 1217 if (sep == (struct servtab *)0) { 1218 syslog(LOG_ERR, "Out of memory."); 1219 exit(-1); 1220 } 1221 *sep = *cp; 1222 sep->se_fd = -1; 1223 sep->se_rpcprog = -1; 1224 omask = sigblock(SIGBLOCK); 1225 sep->se_next = servtab; 1226 servtab = sep; 1227 sigsetmask(omask); 1228 return (sep); 1229} 1230 1231FILE *fconfig = NULL; 1232struct servtab serv; 1233char line[LINE_MAX]; 1234char *defhost; 1235#ifdef IPSEC 1236static char *policy = NULL; 1237#endif 1238 1239int 1240setconfig() 1241{ 1242 if (defhost) 1243 free(defhost); 1244 defhost = newstr("*"); 1245#ifdef IPSEC 1246 if (policy) 1247 free(policy); 1248 policy = NULL; 1249#endif 1250 if (fconfig != NULL) { 1251 fseek(fconfig, 0L, SEEK_SET); 1252 return (1); 1253 } 1254 fconfig = fopen(CONFIG, "r"); 1255 return (fconfig != NULL); 1256} 1257 1258void 1259endconfig() 1260{ 1261 if (fconfig) { 1262 (void) fclose(fconfig); 1263 fconfig = NULL; 1264 } 1265 if (defhost) { 1266 free(defhost); 1267 defhost = 0; 1268 } 1269} 1270 1271struct servtab * 1272getconfigent() 1273{ 1274 struct servtab *sep = &serv; 1275 int argc, val; 1276 char *cp, *cp0, *arg, *buf0, *buf1, *sz0, *sz1; 1277 static char TCPMUX_TOKEN[] = "tcpmux/"; 1278#define MUX_LEN (sizeof(TCPMUX_TOKEN)-1) 1279 char *hostdelim; 1280 1281more: 1282 while ((cp = nextline(fconfig))) { 1283#ifdef IPSEC 1284 /* lines starting with #@ is not a comment, but the policy */ 1285 if (cp[0] == '#' && cp[1] == '@') { 1286 char *p; 1287 for (p = cp + 2; p && *p && isspace(*p); p++) 1288 ; 1289 if (*p == '\0') { 1290 if (policy) 1291 free(policy); 1292 policy = NULL; 1293 } else { 1294 if (ipsecsetup_test(p) < 0) { 1295 syslog(LOG_ERR, 1296 "%s: invalid ipsec policy \"%s\"", 1297 CONFIG, p); 1298 exit(-1); 1299 } else { 1300 if (policy) 1301 free(policy); 1302 policy = newstr(p); 1303 } 1304 } 1305 } 1306#endif 1307 if (*cp == '#' || *cp == '\0') 1308 continue; 1309#ifdef MULOG 1310 /* Avoid use of `skip' if there is a danger of it looking 1311 * at continuation lines. 1312 */ 1313 do { 1314 cp++; 1315 } while (*cp == ' ' || *cp == '\t'); 1316 if (*cp == '\0') 1317 continue; 1318 if ((arg = skip(&cp)) == NULL) 1319 continue; 1320 if (strcmp(arg, "DOMAIN")) 1321 continue; 1322 if (curdom) 1323 free(curdom); 1324 curdom = NULL; 1325 while (*cp == ' ' || *cp == '\t') 1326 cp++; 1327 if (*cp == '\0') 1328 continue; 1329 arg = cp; 1330 while (*cp && *cp != ' ' && *cp != '\t') 1331 cp++; 1332 if (*cp != '\0') 1333 *cp++ = '\0'; 1334 curdom = newstr(arg); 1335#endif 1336 break; 1337 } 1338 if (cp == NULL) 1339 return ((struct servtab *)0); 1340 /* 1341 * clear the static buffer, since some fields (se_ctrladdr, 1342 * for example) don't get initialized here. 1343 */ 1344 memset((caddr_t)sep, 0, sizeof *sep); 1345 arg = skip(&cp); 1346 if (cp == NULL) { 1347 /* got an empty line containing just blanks/tabs. */ 1348 goto more; 1349 } 1350 /* Check for a host name. */ 1351 hostdelim = strrchr(arg, ':'); 1352 if (hostdelim) { 1353 *hostdelim = '\0'; 1354 sep->se_hostaddr = newstr(arg); 1355 arg = hostdelim + 1; 1356 /* 1357 * If the line is of the form `host:', then just change the 1358 * default host for the following lines. 1359 */ 1360 if (*arg == '\0') { 1361 arg = skip(&cp); 1362 if (cp == NULL) { 1363 free(defhost); 1364 defhost = sep->se_hostaddr; 1365 goto more; 1366 } 1367 } 1368 } else 1369 sep->se_hostaddr = newstr(defhost); 1370 if (strncmp(arg, TCPMUX_TOKEN, MUX_LEN) == 0) { 1371 char *c = arg + MUX_LEN; 1372 if (*c == '+') { 1373 sep->se_type = MUXPLUS_TYPE; 1374 c++; 1375 } else 1376 sep->se_type = MUX_TYPE; 1377 sep->se_service = newstr(c); 1378 } else { 1379 sep->se_service = newstr(arg); 1380 sep->se_type = NORM_TYPE; 1381 } 1382 1383 arg = sskip(&cp); 1384 if (strcmp(arg, "stream") == 0) 1385 sep->se_socktype = SOCK_STREAM; 1386 else if (strcmp(arg, "dgram") == 0) 1387 sep->se_socktype = SOCK_DGRAM; 1388 else if (strcmp(arg, "rdm") == 0) 1389 sep->se_socktype = SOCK_RDM; 1390 else if (strcmp(arg, "seqpacket") == 0) 1391 sep->se_socktype = SOCK_SEQPACKET; 1392 else if (strcmp(arg, "raw") == 0) 1393 sep->se_socktype = SOCK_RAW; 1394 else 1395 sep->se_socktype = -1; 1396 1397 sep->se_proto = newstr(sskip(&cp)); 1398 1399#define MALFORMED(arg) \ 1400do { \ 1401 syslog(LOG_ERR, "%s: malformed buffer size option `%s'", \ 1402 sep->se_service, (arg)); \ 1403 goto more; \ 1404} while (0) 1405 1406#define GETVAL(arg) \ 1407do { \ 1408 if (!isdigit(*(arg))) \ 1409 MALFORMED(arg); \ 1410 val = strtol((arg), &cp0, 10); \ 1411 if (cp0 != NULL) { \ 1412 if (cp0[1] != '\0') \ 1413 MALFORMED((arg)); \ 1414 if (cp0[0] == 'k') \ 1415 val *= 1024; \ 1416 if (cp0[0] == 'm') \ 1417 val *= 1024 * 1024; \ 1418 } \ 1419 if (val < 1) { \ 1420 syslog(LOG_ERR, "%s: invalid buffer size `%s'", \ 1421 sep->se_service, (arg)); \ 1422 goto more; \ 1423 } \ 1424} while (0) 1425 1426#define ASSIGN(arg) \ 1427do { \ 1428 if (strcmp((arg), "sndbuf") == 0) \ 1429 sep->se_sndbuf = val; \ 1430 else if (strcmp((arg), "rcvbuf") == 0) \ 1431 sep->se_rcvbuf = val; \ 1432 else \ 1433 MALFORMED((arg)); \ 1434} while (0) 1435 1436 /* 1437 * Extract the send and receive buffer sizes before parsing 1438 * the protocol. 1439 */ 1440 sep->se_sndbuf = sep->se_rcvbuf = 0; 1441 buf0 = buf1 = sz0 = sz1 = NULL; 1442 if ((buf0 = strchr(sep->se_proto, ',')) != NULL) { 1443 /* Not meaningful for Tcpmux services. */ 1444 if (sep->se_type != NORM_TYPE) { 1445 syslog(LOG_ERR, "%s: can't specify buffer sizes for " 1446 "tcpmux services", sep->se_service); 1447 goto more; 1448 } 1449 1450 /* Skip the , */ 1451 *buf0++ = '\0'; 1452 1453 /* Check to see if another socket buffer size was specified. */ 1454 if ((buf1 = strchr(buf0, ',')) != NULL) { 1455 /* Skip the , */ 1456 *buf1++ = '\0'; 1457 1458 /* Make sure a 3rd one wasn't specified. */ 1459 if (strchr(buf1, ',') != NULL) { 1460 syslog(LOG_ERR, "%s: too many buffer sizes", 1461 sep->se_service); 1462 goto more; 1463 } 1464 1465 /* Locate the size. */ 1466 if ((sz1 = strchr(buf1, '=')) == NULL) 1467 MALFORMED(buf1); 1468 1469 /* Skip the = */ 1470 *sz1++ = '\0'; 1471 } 1472 1473 /* Locate the size. */ 1474 if ((sz0 = strchr(buf0, '=')) == NULL) 1475 MALFORMED(buf0); 1476 1477 /* Skip the = */ 1478 *sz0++ = '\0'; 1479 1480 GETVAL(sz0); 1481 ASSIGN(buf0); 1482 1483 if (buf1 != NULL) { 1484 GETVAL(sz1); 1485 ASSIGN(buf1); 1486 } 1487 } 1488 1489#undef ASSIGN 1490#undef GETVAL 1491#undef MALFORMED 1492 1493 if (strcmp(sep->se_proto, "unix") == 0) { 1494 sep->se_family = AF_LOCAL; 1495 } else { 1496 val = strlen(sep->se_proto); 1497 if (!val) { 1498 syslog(LOG_ERR, "%s: invalid protocol specified", 1499 sep->se_service); 1500 goto more; 1501 } 1502 val = sep->se_proto[val - 1]; 1503 switch (val) { 1504 case '4': /*tcp4 or udp4*/ 1505 sep->se_family = AF_INET; 1506 break; 1507#ifdef INET6 1508 case '6': /*tcp6 or udp6*/ 1509 sep->se_family = AF_INET6; 1510 break; 1511#endif 1512 default: 1513 sep->se_family = AF_INET; /*will become AF_INET6*/ 1514 break; 1515 } 1516 if (strncmp(sep->se_proto, "rpc/", 4) == 0) { 1517#ifdef RPC 1518 char *cp, *ccp; 1519 cp = strchr(sep->se_service, '/'); 1520 if (cp == 0) { 1521 syslog(LOG_ERR, "%s: no rpc version", 1522 sep->se_service); 1523 goto more; 1524 } 1525 *cp++ = '\0'; 1526 sep->se_rpcversl = sep->se_rpcversh = 1527 strtol(cp, &ccp, 0); 1528 if (ccp == cp) { 1529 badafterall: 1530 syslog(LOG_ERR, "%s/%s: bad rpc version", 1531 sep->se_service, cp); 1532 goto more; 1533 } 1534 if (*ccp == '-') { 1535 cp = ccp + 1; 1536 sep->se_rpcversh = strtol(cp, &ccp, 0); 1537 if (ccp == cp) 1538 goto badafterall; 1539 } 1540#else 1541 syslog(LOG_ERR, "%s: rpc services not suported", 1542 sep->se_service); 1543 goto more; 1544#endif /* RPC */ 1545 } 1546 } 1547 arg = sskip(&cp); 1548 { 1549 char *cp; 1550 if ((cp = strchr(arg, ':')) == NULL) 1551 cp = strchr(arg, '.'); 1552 if (cp != NULL) { 1553 *cp++ = '\0'; 1554 sep->se_max = atoi(cp); 1555 } else 1556 sep->se_max = TOOMANY; 1557 } 1558 sep->se_wait = strcmp(arg, "wait") == 0; 1559 if (ISMUX(sep)) { 1560 /* 1561 * Silently enforce "nowait" for TCPMUX services since 1562 * they don't have an assigned port to listen on. 1563 */ 1564 sep->se_wait = 0; 1565 1566 if (strncmp(sep->se_proto, "tcp", 3)) { 1567 syslog(LOG_ERR, 1568 "%s: bad protocol for tcpmux service %s", 1569 CONFIG, sep->se_service); 1570 goto more; 1571 } 1572 if (sep->se_socktype != SOCK_STREAM) { 1573 syslog(LOG_ERR, 1574 "%s: bad socket type for tcpmux service %s", 1575 CONFIG, sep->se_service); 1576 goto more; 1577 } 1578 } 1579 sep->se_user = newstr(sskip(&cp)); 1580 if ((sep->se_group = strchr(sep->se_user, ':')) != NULL) 1581 *sep->se_group++ = '\0'; 1582 else if ((sep->se_group = strchr(sep->se_user, '.')) != NULL) 1583 *sep->se_group++ = '\0'; 1584 1585 sep->se_server = newstr(sskip(&cp)); 1586 if (strcmp(sep->se_server, "internal") == 0) { 1587 struct biltin *bi; 1588 1589 for (bi = biltins; bi->bi_service; bi++) 1590 if (bi->bi_socktype == sep->se_socktype && 1591 strcmp(bi->bi_service, sep->se_service) == 0) 1592 break; 1593 if (bi->bi_service == 0) { 1594 syslog(LOG_ERR, "internal service %s unknown", 1595 sep->se_service); 1596 goto more; 1597 } 1598 sep->se_bi = bi; 1599 sep->se_wait = bi->bi_wait; 1600 } else 1601 sep->se_bi = NULL; 1602 argc = 0; 1603 for (arg = skip(&cp); cp; arg = skip(&cp)) { 1604#if MULOG 1605 char *colon; 1606 1607 if (argc == 0 && (colon = strrchr(arg, ':'))) { 1608 while (arg < colon) { 1609 int x; 1610 char *ccp; 1611 1612 switch (*arg++) { 1613 case 'l': 1614 x = 1; 1615 if (isdigit(*arg)) { 1616 x = strtol(arg, &ccp, 0); 1617 if (ccp == arg) 1618 break; 1619 arg = ccp; 1620 } 1621 sep->se_log &= ~MULOG_RFC931; 1622 sep->se_log |= x; 1623 break; 1624 case 'a': 1625 sep->se_log |= MULOG_RFC931; 1626 break; 1627 default: 1628 break; 1629 } 1630 } 1631 arg = colon + 1; 1632 } 1633#endif 1634 if (argc < MAXARGV) 1635 sep->se_argv[argc++] = newstr(arg); 1636 } 1637 while (argc <= MAXARGV) 1638 sep->se_argv[argc++] = NULL; 1639#ifdef IPSEC 1640 sep->se_policy = policy ? newstr(policy) : NULL; 1641#endif 1642 return (sep); 1643} 1644 1645void 1646freeconfig(cp) 1647 struct servtab *cp; 1648{ 1649 int i; 1650 1651 if (cp->se_hostaddr) 1652 free(cp->se_hostaddr); 1653 if (cp->se_service) 1654 free(cp->se_service); 1655 if (cp->se_proto) 1656 free(cp->se_proto); 1657 if (cp->se_user) 1658 free(cp->se_user); 1659 /* Note: se_group is part of the newstr'ed se_user */ 1660 if (cp->se_server) 1661 free(cp->se_server); 1662 for (i = 0; i < MAXARGV; i++) 1663 if (cp->se_argv[i]) 1664 free(cp->se_argv[i]); 1665#ifdef IPSEC 1666 if (cp->se_policy) 1667 free(cp->se_policy); 1668#endif 1669} 1670 1671 1672/* 1673 * Safe skip - if skip returns null, log a syntax error in the 1674 * configuration file and exit. 1675 */ 1676char * 1677sskip(cpp) 1678 char **cpp; 1679{ 1680 char *cp; 1681 1682 cp = skip(cpp); 1683 if (cp == NULL) { 1684 syslog(LOG_ERR, "%s: syntax error", CONFIG); 1685 exit(-1); 1686 } 1687 return (cp); 1688} 1689 1690char * 1691skip(cpp) 1692 char **cpp; 1693{ 1694 char *cp = *cpp; 1695 char *start; 1696 1697 if (*cpp == NULL) 1698 return ((char *)0); 1699 1700again: 1701 while (*cp == ' ' || *cp == '\t') 1702 cp++; 1703 if (*cp == '\0') { 1704 int c; 1705 1706 c = getc(fconfig); 1707 (void) ungetc(c, fconfig); 1708 if (c == ' ' || c == '\t') 1709 if ((cp = nextline(fconfig))) 1710 goto again; 1711 *cpp = (char *)0; 1712 return ((char *)0); 1713 } 1714 start = cp; 1715 while (*cp && *cp != ' ' && *cp != '\t') 1716 cp++; 1717 if (*cp != '\0') 1718 *cp++ = '\0'; 1719 *cpp = cp; 1720 return (start); 1721} 1722 1723char * 1724nextline(fd) 1725 FILE *fd; 1726{ 1727 char *cp; 1728 1729 if (fgets(line, sizeof (line), fd) == NULL) 1730 return ((char *)0); 1731 cp = strchr(line, '\n'); 1732 if (cp) 1733 *cp = '\0'; 1734 return (line); 1735} 1736 1737char * 1738newstr(cp) 1739 char *cp; 1740{ 1741 if ((cp = strdup(cp ? cp : ""))) 1742 return (cp); 1743 syslog(LOG_ERR, "strdup: %m"); 1744 exit(-1); 1745} 1746 1747void 1748inetd_setproctitle(a, s) 1749 char *a; 1750 int s; 1751{ 1752 int size; 1753 char *cp; 1754 struct sockaddr_storage ss; 1755 char buf[80]; 1756 char hbuf[NI_MAXHOST]; 1757 1758 cp = Argv[0]; 1759 size = sizeof(ss); 1760 if (getpeername(s, (struct sockaddr *)&ss, &size) == 0) { 1761 if (getnameinfo((struct sockaddr *)&ss, ss.ss_len, 1762 hbuf, sizeof(hbuf), NULL, 0, niflags) != 0) 1763 strcpy(hbuf, "?"); 1764 (void)snprintf(buf, sizeof buf, "-%s [%s]", a, hbuf); 1765 } else 1766 (void)snprintf(buf, sizeof buf, "-%s", a); 1767 strncpy(cp, buf, LastArg - cp); 1768 cp += strlen(cp); 1769 while (cp < LastArg) 1770 *cp++ = ' '; 1771} 1772 1773void 1774bump_nofile() 1775{ 1776#ifdef RLIMIT_NOFILE 1777 1778#define FD_CHUNK 32 1779 1780 struct rlimit rl; 1781 1782 if (getrlimit(RLIMIT_NOFILE, &rl) < 0) { 1783 syslog(LOG_ERR, "getrlimit: %m"); 1784 return; 1785 } 1786 rl.rlim_cur = MIN(rl.rlim_max, rl.rlim_cur + FD_CHUNK); 1787 if (rl.rlim_cur <= rlim_ofile_cur) { 1788 syslog(LOG_ERR, 1789 "bump_nofile: cannot extend file limit, max = %d", 1790 (int)rl.rlim_cur); 1791 return; 1792 } 1793 1794 if (setrlimit(RLIMIT_NOFILE, &rl) < 0) { 1795 syslog(LOG_ERR, "setrlimit: %m"); 1796 return; 1797 } 1798 1799 rlim_ofile_cur = rl.rlim_cur; 1800 return; 1801 1802#else 1803 syslog(LOG_ERR, "bump_nofile: cannot extend file limit"); 1804 return; 1805#endif 1806} 1807 1808/* 1809 * Internet services provided internally by inetd: 1810 */ 1811#define BUFSIZE 4096 1812 1813/* ARGSUSED */ 1814void 1815echo_stream(s, sep) /* Echo service -- echo data back */ 1816 int s; 1817 struct servtab *sep; 1818{ 1819 char buffer[BUFSIZE]; 1820 int i; 1821 1822 inetd_setproctitle(sep->se_service, s); 1823 while ((i = read(s, buffer, sizeof(buffer))) > 0 && 1824 write(s, buffer, i) > 0) 1825 ; 1826} 1827 1828/* ARGSUSED */ 1829void 1830echo_dg(s, sep) /* Echo service -- echo data back */ 1831 int s; 1832 struct servtab *sep; 1833{ 1834 char buffer[BUFSIZE]; 1835 int i, size; 1836 struct sockaddr_storage ss; 1837 struct sockaddr *sa; 1838 1839 sa = (struct sockaddr *)&ss; 1840 size = sizeof(ss); 1841 if ((i = recvfrom(s, buffer, sizeof(buffer), 0, sa, &size)) < 0) 1842 return; 1843 if (port_good_dg(sa)) 1844 (void) sendto(s, buffer, i, 0, sa, size); 1845} 1846 1847/* ARGSUSED */ 1848void 1849discard_stream(s, sep) /* Discard service -- ignore data */ 1850 int s; 1851 struct servtab *sep; 1852{ 1853 char buffer[BUFSIZE]; 1854 1855 inetd_setproctitle(sep->se_service, s); 1856 while ((errno = 0, read(s, buffer, sizeof(buffer)) > 0) || 1857 errno == EINTR) 1858 ; 1859} 1860 1861/* ARGSUSED */ 1862void 1863discard_dg(s, sep) /* Discard service -- ignore data */ 1864 int s; 1865 struct servtab *sep; 1866{ 1867 char buffer[BUFSIZE]; 1868 1869 (void) read(s, buffer, sizeof(buffer)); 1870} 1871 1872#include <ctype.h> 1873#define LINESIZ 72 1874char ring[128]; 1875char *endring; 1876 1877void 1878initring() 1879{ 1880 int i; 1881 1882 endring = ring; 1883 1884 for (i = 0; i <= 128; ++i) 1885 if (isprint(i)) 1886 *endring++ = i; 1887} 1888 1889/* ARGSUSED */ 1890void 1891chargen_stream(s, sep) /* Character generator */ 1892 int s; 1893 struct servtab *sep; 1894{ 1895 int len; 1896 char *rs, text[LINESIZ+2]; 1897 1898 inetd_setproctitle(sep->se_service, s); 1899 1900 if (!endring) { 1901 initring(); 1902 rs = ring; 1903 } 1904 1905 text[LINESIZ] = '\r'; 1906 text[LINESIZ + 1] = '\n'; 1907 for (rs = ring;;) { 1908 if ((len = endring - rs) >= LINESIZ) 1909 memmove(text, rs, LINESIZ); 1910 else { 1911 memmove(text, rs, len); 1912 memmove(text + len, ring, LINESIZ - len); 1913 } 1914 if (++rs == endring) 1915 rs = ring; 1916 if (write(s, text, sizeof(text)) != sizeof(text)) 1917 break; 1918 } 1919} 1920 1921/* ARGSUSED */ 1922void 1923chargen_dg(s, sep) /* Character generator */ 1924 int s; 1925 struct servtab *sep; 1926{ 1927 struct sockaddr_storage ss; 1928 struct sockaddr *sa; 1929 static char *rs; 1930 int len, size; 1931 char text[LINESIZ+2]; 1932 1933 if (endring == 0) { 1934 initring(); 1935 rs = ring; 1936 } 1937 1938 sa = (struct sockaddr *)&ss; 1939 size = sizeof(ss); 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, size); 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_storage ss; 2002 struct sockaddr *sa; 2003 int size; 2004 2005 sa = (struct sockaddr *)&ss; 2006 size = sizeof(ss); 2007 if (recvfrom(s, (char *)&result, sizeof(result), 0, sa, &size) < 0) 2008 return; 2009 if (!port_good_dg(sa)) 2010 return; 2011 result = machtime(); 2012 (void) sendto(s, (char *) &result, sizeof(result), 0, sa, size); 2013} 2014 2015/* ARGSUSED */ 2016void 2017daytime_stream(s, sep) /* Return human-readable time of day */ 2018 int s; 2019 struct servtab *sep; 2020{ 2021 char buffer[256]; 2022 time_t clock; 2023 int len; 2024 2025 clock = time((time_t *) 0); 2026 2027 len = snprintf(buffer, sizeof buffer, "%.24s\r\n", ctime(&clock)); 2028 (void) write(s, buffer, len); 2029} 2030 2031/* ARGSUSED */ 2032void 2033daytime_dg(s, sep) /* Return human-readable time of day */ 2034 int s; 2035 struct servtab *sep; 2036{ 2037 char buffer[256]; 2038 time_t clock; 2039 struct sockaddr_storage ss; 2040 struct sockaddr *sa; 2041 int size, len; 2042 2043 clock = time((time_t *) 0); 2044 2045 sa = (struct sockaddr *)&ss; 2046 size = sizeof(ss); 2047 if (recvfrom(s, buffer, sizeof(buffer), 0, sa, &size) < 0) 2048 return; 2049 if (!port_good_dg(sa)) 2050 return; 2051 len = snprintf(buffer, sizeof buffer, "%.24s\r\n", ctime(&clock)); 2052 (void) sendto(s, buffer, len, 0, sa, size); 2053} 2054 2055/* 2056 * print_service: 2057 * Dump relevant information to stderr 2058 */ 2059void 2060print_service(action, sep) 2061 char *action; 2062 struct servtab *sep; 2063{ 2064 if (isrpcservice(sep)) 2065 fprintf(stderr, 2066 "%s: %s rpcprog=%d, rpcvers = %d/%d, proto=%s, wait:max=%d.%d, user:group=%s.%s builtin=%lx server=%s" 2067#ifdef IPSEC 2068 " policy=\"%s\"" 2069#endif 2070 "\n", 2071 action, sep->se_service, 2072 sep->se_rpcprog, sep->se_rpcversh, sep->se_rpcversl, sep->se_proto, 2073 sep->se_wait, sep->se_max, sep->se_user, sep->se_group, 2074 (long)sep->se_bi, sep->se_server 2075#ifdef IPSEC 2076 , (sep->se_policy ? sep->se_policy : "") 2077#endif 2078 ); 2079 else 2080 fprintf(stderr, 2081 "%s: %s proto=%s, wait:max=%d.%d, user:group=%s.%s builtin=%lx server=%s" 2082#ifdef IPSEC 2083 " policy=%s" 2084#endif 2085 "\n", 2086 action, sep->se_service, sep->se_proto, 2087 sep->se_wait, sep->se_max, sep->se_user, sep->se_group, 2088 (long)sep->se_bi, sep->se_server 2089#ifdef IPSEC 2090 , (sep->se_policy ? sep->se_policy : "") 2091#endif 2092 ); 2093} 2094 2095void 2096usage() 2097{ 2098 2099#ifdef LIBWRAP 2100 (void)fprintf(stderr, "usage: %s [-dl] [conf]\n", __progname); 2101#else 2102 (void)fprintf(stderr, "usage: %s [-d] [conf]\n", __progname); 2103#endif 2104 exit(1); 2105} 2106 2107 2108/* 2109 * Based on TCPMUX.C by Mark K. Lottor November 1988 2110 * sri-nic::ps:<mkl>tcpmux.c 2111 */ 2112 2113static int /* # of characters upto \r,\n or \0 */ 2114getline(fd, buf, len) 2115 int fd; 2116 char *buf; 2117 int len; 2118{ 2119 int count = 0, n; 2120 2121 do { 2122 n = read(fd, buf, len-count); 2123 if (n == 0) 2124 return (count); 2125 if (n < 0) 2126 return (-1); 2127 while (--n >= 0) { 2128 if (*buf == '\r' || *buf == '\n' || *buf == '\0') 2129 return (count); 2130 count++; 2131 buf++; 2132 } 2133 } while (count < len); 2134 return (count); 2135} 2136 2137#define MAX_SERV_LEN (256+2) /* 2 bytes for \r\n */ 2138 2139#define strwrite(fd, buf) (void) write(fd, buf, sizeof(buf)-1) 2140 2141void 2142tcpmux(ctrl, sep) 2143 int ctrl; 2144 struct servtab *sep; 2145{ 2146 char service[MAX_SERV_LEN+1]; 2147 int len; 2148 2149 /* Get requested service name */ 2150 if ((len = getline(ctrl, service, MAX_SERV_LEN)) < 0) { 2151 strwrite(ctrl, "-Error reading service name\r\n"); 2152 goto reject; 2153 } 2154 service[len] = '\0'; 2155 2156 if (debug) 2157 fprintf(stderr, "tcpmux: someone wants %s\n", service); 2158 2159 /* 2160 * Help is a required command, and lists available services, 2161 * one per line. 2162 */ 2163 if (!strcasecmp(service, "help")) { 2164 strwrite(ctrl, "+Available services:\r\n"); 2165 strwrite(ctrl, "help\r\n"); 2166 for (sep = servtab; sep; sep = sep->se_next) { 2167 if (!ISMUX(sep)) 2168 continue; 2169 (void)write(ctrl, sep->se_service, 2170 strlen(sep->se_service)); 2171 strwrite(ctrl, "\r\n"); 2172 } 2173 goto reject; 2174 } 2175 2176 /* Try matching a service in inetd.conf with the request */ 2177 for (sep = servtab; sep; sep = sep->se_next) { 2178 if (!ISMUX(sep)) 2179 continue; 2180 if (!strcasecmp(service, sep->se_service)) { 2181 if (ISMUXPLUS(sep)) 2182 strwrite(ctrl, "+Go\r\n"); 2183 run_service(ctrl, sep); 2184 return; 2185 } 2186 } 2187 strwrite(ctrl, "-Service not available\r\n"); 2188reject: 2189 _exit(1); 2190} 2191 2192 2193#ifdef MULOG 2194dolog(sep, ctrl) 2195 struct servtab *sep; 2196 int ctrl; 2197{ 2198 struct sockaddr_storage ss; 2199 struct sockaddr *sa = (struct sockaddr *)&ss; 2200 struct sockaddr_in *sin = (struct sockaddr_in *)&ss; 2201 int len = sizeof(ss); 2202 struct hostent *hp; 2203 char *host, *dp, buf[BUFSIZ], *rfc931_name(); 2204 int connected = 1; 2205 2206 switch (sep->se_family) { 2207 case AF_INET: 2208#ifdef INET6 2209 case AF_INET6: 2210#endif 2211 break; 2212 default; 2213 return; 2214 } 2215 2216 if (getpeername(ctrl, sa, &len) < 0) { 2217 if (errno != ENOTCONN) { 2218 syslog(LOG_ERR, "getpeername: %m"); 2219 return; 2220 } 2221 if (recvfrom(ctrl, buf, sizeof(buf), MSG_PEEK, sa, &len) < 0) { 2222 syslog(LOG_ERR, "recvfrom: %m"); 2223 return; 2224 } 2225 connected = 0; 2226 } 2227 switch (sa->sa_family) { 2228 case AF_INET: 2229#ifdef INET6 2230 case AF_INET6: 2231#endif 2232 break; 2233 default; 2234 syslog(LOG_ERR, "unexpected address family %u", sa->sa_family); 2235 return; 2236 } 2237 2238 if (getnameinfo(sa, sa->sa_len, buf, sizeof(buf), NULL, 0, 0) != 0) 2239 strcpy(buf, "?"); 2240 host = buf; 2241 2242 switch (sep->se_log & ~MULOG_RFC931) { 2243 case 0: 2244 return; 2245 case 1: 2246 if (curdom == NULL || *curdom == '\0') 2247 break; 2248 dp = host + strlen(host) - strlen(curdom); 2249 if (dp < host) 2250 break; 2251 if (debug) 2252 fprintf(stderr, "check \"%s\" against curdom \"%s\"\n", 2253 host, curdom); 2254 if (strcasecmp(dp, curdom) == 0) 2255 return; 2256 break; 2257 case 2: 2258 default: 2259 break; 2260 } 2261 2262 openlog("", LOG_NOWAIT, MULOG); 2263 2264 if (connected && (sep->se_log & MULOG_RFC931)) 2265 syslog(LOG_INFO, "%s@%s wants %s", 2266 rfc931_name(sa, ctrl), host, sep->se_service); 2267 else 2268 syslog(LOG_INFO, "%s wants %s", 2269 host, sep->se_service); 2270} 2271 2272/* 2273 * From tcp_log by 2274 * Wietse Venema, Eindhoven University of Technology, The Netherlands. 2275 */ 2276#if 0 2277static char sccsid[] = "@(#) rfc931.c 1.3 92/08/31 22:54:46"; 2278#endif 2279 2280#include <setjmp.h> 2281 2282#define RFC931_PORT 113 /* Semi-well-known port */ 2283#define TIMEOUT 4 2284#define TIMEOUT2 10 2285 2286static jmp_buf timebuf; 2287 2288/* timeout - handle timeouts */ 2289 2290static void timeout(sig) 2291int sig; 2292{ 2293 longjmp(timebuf, sig); 2294} 2295 2296/* rfc931_name - return remote user name */ 2297 2298char * 2299rfc931_name(there, ctrl) 2300struct sockaddr *there; /* remote link information */ 2301int ctrl; 2302{ 2303 struct sockaddr_storage here; /* local link information */ 2304 struct sockaddr_storage sin; /* for talking to RFC931 daemon */ 2305 int length; 2306 int s; 2307 unsigned remote; 2308 unsigned local; 2309 static char user[256]; /* XXX */ 2310 char buf[256]; 2311 char *cp; 2312 char *result = "USER_UNKNOWN"; 2313 int len; 2314 u_int16_t myport, hisport; 2315 2316 /* Find out local port number of our stdin. */ 2317 2318 length = sizeof(here); 2319 if (getsockname(ctrl, (struct sockaddr *) &here, &length) == -1) { 2320 syslog(LOG_ERR, "getsockname: %m"); 2321 return (result); 2322 } 2323 switch (here.ss_family) { 2324 case AF_INET: 2325 myport = ((struct sockaddr_in *)&here)->sin_port; 2326 break; 2327#ifdef INET6 2328 case AF_INET6: 2329 myport = ((struct sockaddr_in6 *)&here)->sin6_port; 2330 break; 2331#endif 2332 } 2333 switch (there->sa_family) { 2334 case AF_INET: 2335 hisport = ((struct sockaddr_in *)sa)->sin_port; 2336 break; 2337#ifdef INET6 2338 case AF_INET6: 2339 hisport = ((struct sockaddr_in6 *)sa)->sin6_port; 2340 break; 2341#endif 2342 } 2343 /* Set up timer so we won't get stuck. */ 2344 2345 if ((s = socket(here.ss_family, SOCK_STREAM, 0)) == -1) { 2346 syslog(LOG_ERR, "socket: %m"); 2347 return (result); 2348 } 2349 2350 sin = here; 2351 switch (sin.ss_family) { 2352 case AF_INET: 2353 ((struct sockaddr_in *)&sin)->sin_port = htons(0); 2354 break; 2355#ifdef INET6 2356 case AF_INET6: 2357 ((struct sockaddr_in6 *)&sin)->sin6_port = htons(0); 2358 break; 2359#endif 2360 } 2361 if (bind(s, (struct sockaddr *) &sin, sin.ss_len) == -1) { 2362 syslog(LOG_ERR, "bind: %m"); 2363 return (result); 2364 } 2365 2366 signal(SIGALRM, timeout); 2367 if (setjmp(timebuf)) { 2368 close(s); /* not: fclose(fp) */ 2369 return (result); 2370 } 2371 alarm(TIMEOUT); 2372 2373 /* Connect to the RFC931 daemon. */ 2374 2375 memcpy(&sin, there, there->sa_len); 2376 switch (sin.ss_family) { 2377 case AF_INET: 2378 ((struct sockaddr_in *)&sin)->sin_port = htons(RFC931_PORT); 2379 break; 2380#ifdef INET6 2381 case AF_INET6: 2382 ((struct sockaddr_in6 *)&sin)->sin6_port = htons(RFC931_PORT); 2383 break; 2384#endif 2385 } 2386 if (connect(s, (struct sockaddr *) &sin, sin.ss_len) == -1) { 2387 close(s); 2388 alarm(0); 2389 return (result); 2390 } 2391 2392 /* Query the RFC 931 server. Would 13-byte writes ever be broken up? */ 2393 (void)snprintf(buf, sizeof buf, "%u,%u\r\n", ntohs(hisport), 2394 ntohs(myport)); 2395 2396 2397 for (len = 0, cp = buf; len < strlen(buf); ) { 2398 int n; 2399 2400 if ((n = write(s, cp, strlen(buf) - len)) == -1) { 2401 close(s); 2402 alarm(0); 2403 return (result); 2404 } 2405 cp += n; 2406 len += n; 2407 } 2408 2409 /* Read response */ 2410 for (cp = buf; cp < buf + sizeof(buf) - 1; ) { 2411 char c; 2412 if (read(s, &c, 1) != 1) { 2413 close(s); 2414 alarm(0); 2415 return (result); 2416 } 2417 if (c == '\n') 2418 break; 2419 *cp++ = c; 2420 } 2421 *cp = '\0'; 2422 2423 if (sscanf(buf, "%u , %u : USERID :%*[^:]:%255s", &remote, &local, user) == 3 2424 && ntohs(hisport) == remote 2425 && ntohs(myport) == local) { 2426 2427 /* Strip trailing carriage return. */ 2428 if (cp = strchr(user, '\r')) 2429 *cp = 0; 2430 result = user; 2431 } 2432 2433 alarm(0); 2434 close(s); 2435 return (result); 2436} 2437#endif 2438 2439/* 2440 * check if the port where send data to is one of the obvious ports 2441 * that are used for denial of service attacks like two echo ports 2442 * just echoing data between them 2443 */ 2444int 2445port_good_dg(sa) 2446 struct sockaddr *sa; 2447{ 2448 u_int16_t port; 2449 int i, bad; 2450 char hbuf[NI_MAXHOST]; 2451 2452 bad = 0; 2453 2454 switch (sa->sa_family) { 2455 case AF_INET: 2456 port = ntohs(((struct sockaddr_in *)sa)->sin_port); 2457 break; 2458#ifdef INET6 2459 case AF_INET6: 2460 port = ntohs(((struct sockaddr_in6 *)sa)->sin6_port); 2461 break; 2462#endif 2463 default: 2464 /* XXX unsupported af, is it safe to assume it to be safe? */ 2465 return 1; 2466 } 2467 2468 for (i = 0; bad_ports[i] != 0; i++) 2469 if (port == bad_ports[i]) { 2470 bad = 1; 2471 break; 2472 } 2473 2474 if (bad) { 2475 if (getnameinfo(sa, sa->sa_len, hbuf, sizeof(hbuf), 2476 NULL, 0, niflags) != 0) 2477 strcpy(hbuf, "?"); 2478 syslog(LOG_WARNING,"Possible DoS attack from %s, Port %d", 2479 hbuf, port); 2480 return (0); 2481 } else 2482 return (1); 2483} 2484 2485