1 /*- 2 * Copyright (c) 1988, 1989 The Regents of the University of California. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 #ifndef lint 35 char copyright[] = 36 "@(#) Copyright (c) 1988, 1989 The Regents of the University of California.\n\ 37 All rights reserved.\n"; 38 #endif /* not lint */ 39 40 #ifndef lint 41 /*static char sccsid[] = "from: @(#)rshd.c 5.38 (Berkeley) 3/2/91";*/ 42 static char rcsid[] = "$Id: rshd.c,v 1.6 1994/05/19 22:54:19 pk Exp $"; 43 #endif /* not lint */ 44 45 /* 46 * From: 47 * $Source: /cvsroot/src/libexec/rshd/rshd.c,v $ 48 * $Header: /mit/kerberos/ucb/mit/rshd/RCS/rshd.c,v 49 * 5.2 89/07/31 19:30:04 kfall Exp $ 50 */ 51 52 /* 53 * remote shell server: 54 * [port]\0 55 * remuser\0 56 * locuser\0 57 * command\0 58 * data 59 */ 60 #include <sys/param.h> 61 #include <sys/ioctl.h> 62 #include <sys/time.h> 63 #include <fcntl.h> 64 #include <signal.h> 65 66 #include <sys/socket.h> 67 #include <netinet/in.h> 68 #include <arpa/inet.h> 69 #include <netdb.h> 70 71 #include <pwd.h> 72 #include <syslog.h> 73 #include <arpa/nameser.h> 74 #include <resolv.h> 75 #include <unistd.h> 76 #include <errno.h> 77 #include <stdio.h> 78 #include <stdlib.h> 79 #include <string.h> 80 #include <paths.h> 81 82 int keepalive = 1; 83 int check_all = 0; 84 int paranoid = 0; 85 char *index(), *rindex(), *strncat(); 86 /*VARARGS1*/ 87 int error(); 88 int sent_null; 89 90 #ifdef KERBEROS 91 #include <kerberosIV/des.h> 92 #include <kerberosIV/krb.h> 93 #define VERSION_SIZE 9 94 #define SECURE_MESSAGE "This rsh session is using DES encryption for all transmissions.\r\n" 95 #define OPTIONS "alknvxL" 96 char authbuf[sizeof(AUTH_DAT)]; 97 char tickbuf[sizeof(KTEXT_ST)]; 98 int doencrypt, use_kerberos, vacuous; 99 Key_schedule schedule; 100 #else 101 #define OPTIONS "alnL" 102 #endif 103 104 /*ARGSUSED*/ 105 main(argc, argv) 106 int argc; 107 char **argv; 108 { 109 extern int opterr, optind; 110 extern int __check_rhosts_file; 111 struct linger linger; 112 int ch, on = 1, fromlen; 113 struct sockaddr_in from; 114 115 openlog("rshd", LOG_PID | LOG_ODELAY, LOG_DAEMON); 116 117 opterr = 0; 118 while ((ch = getopt(argc, argv, OPTIONS)) != EOF) 119 switch (ch) { 120 case 'a': 121 check_all = 1; 122 break; 123 124 case 'l': 125 __check_rhosts_file = 0; 126 break; 127 128 case 'n': 129 keepalive = 0; 130 break; 131 #ifdef KERBEROS 132 case 'k': 133 use_kerberos = 1; 134 break; 135 136 case 'v': 137 vacuous = 1; 138 break; 139 140 #ifdef CRYPT 141 case 'x': 142 doencrypt = 1; 143 break; 144 #endif 145 #endif 146 147 case 'L': 148 paranoid = 1; 149 break; 150 151 case '?': 152 default: 153 usage(); 154 exit(2); 155 } 156 157 argc -= optind; 158 argv += optind; 159 160 #ifdef KERBEROS 161 if (use_kerberos && vacuous) { 162 syslog(LOG_ERR, "only one of -k and -v allowed"); 163 exit(2); 164 } 165 #ifdef CRYPT 166 if (doencrypt && !use_kerberos) { 167 syslog(LOG_ERR, "-k is required for -x"); 168 exit(2); 169 } 170 #endif 171 #endif 172 173 fromlen = sizeof (from); 174 if (getpeername(0, (struct sockaddr *)&from, &fromlen) < 0) { 175 syslog(LOG_ERR, "getpeername: %m"); 176 _exit(1); 177 } 178 if (keepalive && 179 setsockopt(0, SOL_SOCKET, SO_KEEPALIVE, (char *)&on, 180 sizeof(on)) < 0) 181 syslog(LOG_WARNING, "setsockopt (SO_KEEPALIVE): %m"); 182 linger.l_onoff = 1; 183 linger.l_linger = 60; /* XXX */ 184 if (setsockopt(0, SOL_SOCKET, SO_LINGER, (char *)&linger, 185 sizeof (linger)) < 0) 186 syslog(LOG_WARNING, "setsockopt (SO_LINGER): %m"); 187 doit(&from); 188 } 189 190 char username[20] = "USER="; 191 char homedir[64] = "HOME="; 192 char shell[64] = "SHELL="; 193 char path[100] = "PATH="; 194 char *envinit[] = 195 {homedir, shell, path, username, 0}; 196 char **environ; 197 198 doit(fromp) 199 struct sockaddr_in *fromp; 200 { 201 char cmdbuf[NCARGS+1], *cp; 202 char locuser[16], remuser[16]; 203 struct passwd *pwd; 204 int s; 205 struct hostent *hp; 206 char *hostname, *errorstr = NULL, *errorhost; 207 u_short port; 208 int pv[2], pid, cc; 209 int nfd; 210 fd_set ready, readfrom; 211 char buf[BUFSIZ], sig; 212 int one = 1; 213 char remotehost[2 * MAXHOSTNAMELEN + 1]; 214 215 #ifdef KERBEROS 216 AUTH_DAT *kdata = (AUTH_DAT *) NULL; 217 KTEXT ticket = (KTEXT) NULL; 218 char instance[INST_SZ], version[VERSION_SIZE]; 219 struct sockaddr_in fromaddr; 220 int rc; 221 long authopts; 222 int pv1[2], pv2[2]; 223 fd_set wready, writeto; 224 225 fromaddr = *fromp; 226 #endif 227 228 (void) signal(SIGINT, SIG_DFL); 229 (void) signal(SIGQUIT, SIG_DFL); 230 (void) signal(SIGTERM, SIG_DFL); 231 #ifdef DEBUG 232 { int t = open(_PATH_TTY, 2); 233 if (t >= 0) { 234 ioctl(t, TIOCNOTTY, (char *)0); 235 (void) close(t); 236 } 237 } 238 #endif 239 fromp->sin_port = ntohs((u_short)fromp->sin_port); 240 if (fromp->sin_family != AF_INET) { 241 syslog(LOG_ERR, "malformed \"from\" address (af %d)\n", 242 fromp->sin_family); 243 exit(1); 244 } 245 #ifdef IP_OPTIONS 246 { 247 u_char optbuf[BUFSIZ/3], *cp; 248 char lbuf[BUFSIZ], *lp; 249 int optsize = sizeof(optbuf), ipproto; 250 struct protoent *ip; 251 252 if ((ip = getprotobyname("ip")) != NULL) 253 ipproto = ip->p_proto; 254 else 255 ipproto = IPPROTO_IP; 256 if (!getsockopt(0, ipproto, IP_OPTIONS, (char *)optbuf, &optsize) && 257 optsize != 0) { 258 lp = lbuf; 259 for (cp = optbuf; optsize > 0; cp++, optsize--, lp += 3) 260 sprintf(lp, " %2.2x", *cp); 261 syslog(LOG_NOTICE, 262 "Connection received from %s using IP options (ignored):%s", 263 inet_ntoa(fromp->sin_addr), lbuf); 264 if (setsockopt(0, ipproto, IP_OPTIONS, 265 (char *)NULL, optsize) != 0) { 266 syslog(LOG_ERR, "setsockopt IP_OPTIONS NULL: %m"); 267 exit(1); 268 } 269 } 270 } 271 #endif 272 273 #ifdef KERBEROS 274 if (!use_kerberos) 275 #endif 276 if (fromp->sin_port >= IPPORT_RESERVED || 277 fromp->sin_port < IPPORT_RESERVED/2) { 278 syslog(LOG_NOTICE|LOG_AUTH, 279 "Connection from %s on illegal port", 280 inet_ntoa(fromp->sin_addr)); 281 exit(1); 282 } 283 284 (void) alarm(60); 285 port = 0; 286 for (;;) { 287 char c; 288 if ((cc = read(0, &c, 1)) != 1) { 289 if (cc < 0) 290 syslog(LOG_NOTICE, "read: %m"); 291 shutdown(0, 1+1); 292 exit(1); 293 } 294 if (c== 0) 295 break; 296 port = port * 10 + c - '0'; 297 } 298 299 (void) alarm(0); 300 if (port != 0) { 301 int lport = IPPORT_RESERVED - 1; 302 s = rresvport(&lport); 303 if (s < 0) { 304 syslog(LOG_ERR, "can't get stderr port: %m"); 305 exit(1); 306 } 307 #ifdef KERBEROS 308 if (!use_kerberos) 309 #endif 310 if (port >= IPPORT_RESERVED) { 311 syslog(LOG_ERR, "2nd port not reserved\n"); 312 exit(1); 313 } 314 fromp->sin_port = htons(port); 315 if (connect(s, (struct sockaddr *)fromp, sizeof (*fromp)) < 0) { 316 syslog(LOG_INFO, "connect second port: %m"); 317 exit(1); 318 } 319 } 320 321 #ifdef KERBEROS 322 if (vacuous) { 323 error("rshd: remote host requires Kerberos authentication\n"); 324 exit(1); 325 } 326 #endif 327 328 #ifdef notdef 329 /* from inetd, socket is already on 0, 1, 2 */ 330 dup2(f, 0); 331 dup2(f, 1); 332 dup2(f, 2); 333 #endif 334 hp = gethostbyaddr((char *)&fromp->sin_addr, sizeof (struct in_addr), 335 fromp->sin_family); 336 if (hp) { 337 /* 338 * If name returned by gethostbyaddr is in our domain, 339 * attempt to verify that we haven't been fooled by someone 340 * in a remote net; look up the name and check that this 341 * address corresponds to the name. 342 */ 343 hostname = hp->h_name; 344 #ifdef KERBEROS 345 if (!use_kerberos) 346 #endif 347 if (check_all || local_domain(hp->h_name)) { 348 strncpy(remotehost, hp->h_name, sizeof(remotehost) - 1); 349 remotehost[sizeof(remotehost) - 1] = 0; 350 errorhost = remotehost; 351 #ifdef RES_DNSRCH 352 _res.options &= ~RES_DNSRCH; 353 #endif 354 hp = gethostbyname(remotehost); 355 if (hp == NULL) { 356 syslog(LOG_INFO, 357 "Couldn't look up address for %s", 358 remotehost); 359 errorstr = 360 "Couldn't look up address for your host (%s)\n"; 361 hostname = inet_ntoa(fromp->sin_addr); 362 } else for (; ; hp->h_addr_list++) { 363 if (hp->h_addr_list[0] == NULL) { 364 syslog(LOG_NOTICE, 365 "Host addr %s not listed for host %s", 366 inet_ntoa(fromp->sin_addr), 367 hp->h_name); 368 errorstr = 369 "Host address mismatch for %s\n"; 370 hostname = inet_ntoa(fromp->sin_addr); 371 break; 372 } 373 if (!bcmp(hp->h_addr_list[0], 374 (caddr_t)&fromp->sin_addr, 375 sizeof(fromp->sin_addr))) { 376 hostname = hp->h_name; 377 break; 378 } 379 } 380 } 381 } else 382 errorhost = hostname = inet_ntoa(fromp->sin_addr); 383 384 #ifdef KERBEROS 385 if (use_kerberos) { 386 kdata = (AUTH_DAT *) authbuf; 387 ticket = (KTEXT) tickbuf; 388 authopts = 0L; 389 strcpy(instance, "*"); 390 version[VERSION_SIZE - 1] = '\0'; 391 #ifdef CRYPT 392 if (doencrypt) { 393 struct sockaddr_in local_addr; 394 rc = sizeof(local_addr); 395 if (getsockname(0, (struct sockaddr *)&local_addr, 396 &rc) < 0) { 397 syslog(LOG_ERR, "getsockname: %m"); 398 error("rlogind: getsockname: %m"); 399 exit(1); 400 } 401 authopts = KOPT_DO_MUTUAL; 402 rc = krb_recvauth(authopts, 0, ticket, 403 "rcmd", instance, &fromaddr, 404 &local_addr, kdata, "", schedule, 405 version); 406 des_set_key(kdata->session, schedule); 407 } else 408 #endif 409 rc = krb_recvauth(authopts, 0, ticket, "rcmd", 410 instance, &fromaddr, 411 (struct sockaddr_in *) 0, 412 kdata, "", (bit_64 *) 0, version); 413 if (rc != KSUCCESS) { 414 error("Kerberos authentication failure: %s\n", 415 krb_err_txt[rc]); 416 exit(1); 417 } 418 } else 419 #endif 420 getstr(remuser, sizeof(remuser), "remuser"); 421 422 getstr(locuser, sizeof(locuser), "locuser"); 423 getstr(cmdbuf, sizeof(cmdbuf), "command"); 424 setpwent(); 425 pwd = getpwnam(locuser); 426 if (pwd == NULL) { 427 if (errorstr == NULL) 428 errorstr = "Login incorrect.\n"; 429 goto fail; 430 } 431 if (chdir(pwd->pw_dir) < 0) { 432 (void) chdir("/"); 433 #ifdef notdef 434 error("No remote directory.\n"); 435 exit(1); 436 #endif 437 } 438 439 #ifdef KERBEROS 440 if (use_kerberos) { 441 if (pwd->pw_passwd != 0 && *pwd->pw_passwd != '\0') { 442 if (kuserok(kdata, locuser) != 0) { 443 syslog(LOG_NOTICE|LOG_AUTH, 444 "Kerberos shell denied to %s.%s@%s on %s as %s: cmd='%s'; %s", 445 kdata->pname, kdata->pinst, kdata->prealm, 446 hostname, locuser, cmdbuf, errorstr); 447 error("Permission denied.\n"); 448 exit(1); 449 } 450 } 451 } else 452 #endif 453 454 if (errorstr || 455 pwd->pw_passwd != 0 && *pwd->pw_passwd != '\0' && 456 ruserok(hostname, pwd->pw_uid == 0, remuser, locuser) < 0) { 457 fail: 458 if (errorstr == NULL) 459 errorstr = "Permission denied.\n"; 460 461 /* log the (failed) rsh request, if paranoid */ 462 if (paranoid || (pwd && pwd->pw_uid == 0)) 463 syslog(LOG_INFO|LOG_AUTH, 464 "rsh denied to %s@%s as %s: cmd='%s'; %s", 465 remuser, hostname, locuser, cmdbuf, 466 errorstr); 467 468 error(errorstr, errorhost); 469 exit(1); 470 } 471 472 if (pwd->pw_uid && !access(_PATH_NOLOGIN, F_OK)) { 473 error("Logins currently disabled.\n"); 474 exit(1); 475 } 476 477 (void) write(2, "\0", 1); 478 sent_null = 1; 479 480 if (port) { 481 if (pipe(pv) < 0) { 482 error("Can't make pipe.\n"); 483 exit(1); 484 } 485 #ifdef CRYPT 486 #ifdef KERBEROS 487 if (doencrypt) { 488 if (pipe(pv1) < 0) { 489 error("Can't make 2nd pipe.\n"); 490 exit(1); 491 } 492 if (pipe(pv2) < 0) { 493 error("Can't make 3rd pipe.\n"); 494 exit(1); 495 } 496 } 497 #endif 498 #endif 499 pid = fork(); 500 if (pid == -1) { 501 error("Can't fork; try again.\n"); 502 exit(1); 503 } 504 if (pid) { 505 #ifdef CRYPT 506 #ifdef KERBEROS 507 if (doencrypt) { 508 static char msg[] = SECURE_MESSAGE; 509 (void) close(pv1[1]); 510 (void) close(pv2[1]); 511 des_write(s, msg, sizeof(msg)); 512 513 } else 514 #endif 515 #endif 516 { 517 (void) close(0); (void) close(1); 518 } 519 (void) close(2); (void) close(pv[1]); 520 521 FD_ZERO(&readfrom); 522 FD_SET(s, &readfrom); 523 FD_SET(pv[0], &readfrom); 524 if (pv[0] > s) 525 nfd = pv[0]; 526 else 527 nfd = s; 528 #ifdef CRYPT 529 #ifdef KERBEROS 530 if (doencrypt) { 531 FD_ZERO(&writeto); 532 FD_SET(pv2[0], &writeto); 533 FD_SET(pv1[0], &readfrom); 534 535 nfd = MAX(nfd, pv2[0]); 536 nfd = MAX(nfd, pv1[0]); 537 } else 538 #endif 539 #endif 540 ioctl(pv[0], FIONBIO, (char *)&one); 541 542 /* should set s nbio! */ 543 nfd++; 544 do { 545 ready = readfrom; 546 #ifdef CRYPT 547 #ifdef KERBEROS 548 if (doencrypt) { 549 wready = writeto; 550 if (select(nfd, &ready, 551 &wready, (fd_set *) 0, 552 (struct timeval *) 0) < 0) 553 break; 554 } else 555 #endif 556 #endif 557 if (select(nfd, &ready, (fd_set *)0, 558 (fd_set *)0, (struct timeval *)0) < 0) 559 break; 560 if (FD_ISSET(s, &ready)) { 561 int ret; 562 #ifdef CRYPT 563 #ifdef KERBEROS 564 if (doencrypt) 565 ret = des_read(s, &sig, 1); 566 else 567 #endif 568 #endif 569 ret = read(s, &sig, 1); 570 if (ret <= 0) 571 FD_CLR(s, &readfrom); 572 else 573 killpg(pid, sig); 574 } 575 if (FD_ISSET(pv[0], &ready)) { 576 errno = 0; 577 cc = read(pv[0], buf, sizeof(buf)); 578 if (cc <= 0) { 579 shutdown(s, 1+1); 580 FD_CLR(pv[0], &readfrom); 581 } else { 582 #ifdef CRYPT 583 #ifdef KERBEROS 584 if (doencrypt) 585 (void) 586 des_write(s, buf, cc); 587 else 588 #endif 589 #endif 590 (void) 591 write(s, buf, cc); 592 } 593 } 594 #ifdef CRYPT 595 #ifdef KERBEROS 596 if (doencrypt && FD_ISSET(pv1[0], &ready)) { 597 errno = 0; 598 cc = read(pv1[0], buf, sizeof(buf)); 599 if (cc <= 0) { 600 shutdown(pv1[0], 1+1); 601 FD_CLR(pv1[0], &readfrom); 602 } else 603 (void) des_write(1, buf, cc); 604 } 605 606 if (doencrypt && FD_ISSET(pv2[0], &wready)) { 607 errno = 0; 608 cc = des_read(0, buf, sizeof(buf)); 609 if (cc <= 0) { 610 shutdown(pv2[0], 1+1); 611 FD_CLR(pv2[0], &writeto); 612 } else 613 (void) write(pv2[0], buf, cc); 614 } 615 #endif 616 #endif 617 618 } while (FD_ISSET(s, &readfrom) || 619 #ifdef CRYPT 620 #ifdef KERBEROS 621 (doencrypt && FD_ISSET(pv1[0], &readfrom)) || 622 #endif 623 #endif 624 FD_ISSET(pv[0], &readfrom)); 625 exit(0); 626 } 627 setpgrp(0, getpid()); 628 (void) close(s); (void) close(pv[0]); 629 #ifdef CRYPT 630 #ifdef KERBEROS 631 if (doencrypt) { 632 close(pv1[0]); close(pv2[0]); 633 dup2(pv1[1], 1); 634 dup2(pv2[1], 0); 635 close(pv1[1]); 636 close(pv2[1]); 637 } 638 #endif 639 #endif 640 dup2(pv[1], 2); 641 close(pv[1]); 642 } 643 if (*pwd->pw_shell == '\0') 644 pwd->pw_shell = _PATH_BSHELL; 645 #if BSD > 43 646 if (setlogin(pwd->pw_name) < 0) 647 syslog(LOG_ERR, "setlogin() failed: %m"); 648 #endif 649 (void) setgid((gid_t)pwd->pw_gid); 650 initgroups(pwd->pw_name, pwd->pw_gid); 651 (void) setuid((uid_t)pwd->pw_uid); 652 environ = envinit; 653 strncat(homedir, pwd->pw_dir, sizeof(homedir)-6); 654 strcat(path, _PATH_DEFPATH); 655 strncat(shell, pwd->pw_shell, sizeof(shell)-7); 656 strncat(username, pwd->pw_name, sizeof(username)-6); 657 cp = rindex(pwd->pw_shell, '/'); 658 if (cp) 659 cp++; 660 else 661 cp = pwd->pw_shell; 662 endpwent(); 663 if (paranoid || pwd->pw_uid == 0) { 664 #ifdef KERBEROS 665 if (use_kerberos) 666 syslog(LOG_INFO|LOG_AUTH, 667 "Kerberos shell from %s.%s@%s on %s as %s: cmd='%s'", 668 kdata->pname, kdata->pinst, kdata->prealm, 669 hostname, locuser, cmdbuf); 670 else 671 #endif 672 syslog(LOG_INFO|LOG_AUTH, "%s@%s as %s: cmd='%s'", 673 remuser, hostname, locuser, cmdbuf); 674 } 675 676 677 execl(pwd->pw_shell, cp, "-c", cmdbuf, 0); 678 perror(pwd->pw_shell); 679 exit(1); 680 } 681 682 /* 683 * Report error to client. 684 * Note: can't be used until second socket has connected 685 * to client, or older clients will hang waiting 686 * for that connection first. 687 */ 688 /*VARARGS1*/ 689 error(fmt, a1, a2, a3) 690 char *fmt; 691 int a1, a2, a3; 692 { 693 char buf[BUFSIZ], *bp = buf; 694 695 if (sent_null == 0) 696 *bp++ = 1; 697 (void) sprintf(bp, fmt, a1, a2, a3); 698 (void) write(2, buf, strlen(buf)); 699 } 700 701 getstr(buf, cnt, err) 702 char *buf; 703 int cnt; 704 char *err; 705 { 706 char c; 707 708 do { 709 if (read(0, &c, 1) != 1) 710 exit(1); 711 *buf++ = c; 712 if (--cnt == 0) { 713 error("%s too long\n", err); 714 exit(1); 715 } 716 } while (c != 0); 717 } 718 719 /* 720 * Check whether host h is in our local domain, 721 * defined as sharing the last two components of the domain part, 722 * or the entire domain part if the local domain has only one component. 723 * If either name is unqualified (contains no '.'), 724 * assume that the host is local, as it will be 725 * interpreted as such. 726 */ 727 local_domain(h) 728 char *h; 729 { 730 char localhost[MAXHOSTNAMELEN]; 731 char *p1, *p2, *topdomain(); 732 733 localhost[0] = 0; 734 (void) gethostname(localhost, sizeof(localhost)); 735 p1 = topdomain(localhost); 736 p2 = topdomain(h); 737 if (p1 == NULL || p2 == NULL || !strcasecmp(p1, p2)) 738 return(1); 739 return(0); 740 } 741 742 char * 743 topdomain(h) 744 char *h; 745 { 746 register char *p; 747 char *maybe = NULL; 748 int dots = 0; 749 750 for (p = h + strlen(h); p >= h; p--) { 751 if (*p == '.') { 752 if (++dots == 2) 753 return (p); 754 maybe = p; 755 } 756 } 757 return (maybe); 758 } 759 760 usage() 761 { 762 syslog(LOG_ERR, "usage: rshd [-%s]", OPTIONS); 763 } 764