1 /* 2 * Copyright (c) 1992/3 Theo de Raadt <deraadt@fsa.ca> 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. The name of the author may not be used to endorse or promote 14 * products derived from this software without specific prior written 15 * permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS 18 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 19 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY 21 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 */ 29 30 #ifndef lint 31 static const char rcsid[] = 32 "$FreeBSD$"; 33 #endif /* not lint */ 34 35 #include <sys/param.h> 36 #include <sys/types.h> 37 #include <sys/wait.h> 38 #include <sys/ioctl.h> 39 #include <sys/signal.h> 40 #include <sys/socket.h> 41 #include <sys/file.h> 42 #include <sys/fcntl.h> 43 #include <sys/stat.h> 44 #include <sys/uio.h> 45 #include <ctype.h> 46 #include <dirent.h> 47 #include <err.h> 48 #include <errno.h> 49 #include <netdb.h> 50 #include <signal.h> 51 #include <stdio.h> 52 #include <stdlib.h> 53 #include <string.h> 54 #include <syslog.h> 55 #include <unistd.h> 56 #include <rpc/rpc.h> 57 #include <rpc/xdr.h> 58 #include <net/if.h> 59 #include <netinet/in.h> 60 #include <arpa/inet.h> 61 #include <rpc/pmap_clnt.h> 62 #include <rpc/pmap_prot.h> 63 #include <rpc/pmap_rmt.h> 64 #include <rpc/rpc_com.h> 65 #include <rpcsvc/yp.h> 66 struct dom_binding{}; 67 #include <rpcsvc/ypclnt.h> 68 #include "yp_ping.h" 69 70 #ifndef BINDINGDIR 71 #define BINDINGDIR "/var/yp/binding" 72 #endif 73 74 #ifndef YPBINDLOCK 75 #define YPBINDLOCK "/var/run/ypbind.lock" 76 #endif 77 78 struct _dom_binding { 79 struct _dom_binding *dom_pnext; 80 char dom_domain[YPMAXDOMAIN + 1]; 81 struct sockaddr_in dom_server_addr; 82 long int dom_vers; 83 int dom_lockfd; 84 int dom_alive; 85 int dom_broadcast_pid; 86 int dom_pipe_fds[2]; 87 int dom_default; 88 }; 89 90 #define READFD ypdb->dom_pipe_fds[0] 91 #define WRITEFD ypdb->dom_pipe_fds[1] 92 #define BROADFD broad_domain->dom_pipe_fds[1] 93 94 extern bool_t xdr_domainname(), xdr_ypbind_resp(); 95 extern bool_t xdr_ypreq_key(), xdr_ypresp_val(); 96 extern bool_t xdr_ypbind_setdom(); 97 98 void checkwork __P((void)); 99 void *ypbindproc_null_2_yp __P((SVCXPRT *, void *, CLIENT *)); 100 void *ypbindproc_setdom_2_yp __P((SVCXPRT *, struct ypbind_setdom *, CLIENT *)); 101 void rpc_received __P((char *, struct sockaddr_in *, int )); 102 void broadcast __P((struct _dom_binding *)); 103 int ping __P((struct _dom_binding *)); 104 int tell_parent __P((char *, struct sockaddr_in *)); 105 void handle_children __P(( struct _dom_binding * )); 106 void reaper __P((int)); 107 void terminate __P((int)); 108 void yp_restricted_mode __P((char *)); 109 int verify __P((struct in_addr)); 110 111 char *domain_name; 112 struct _dom_binding *ypbindlist; 113 static struct _dom_binding *broad_domain; 114 115 #define YPSET_NO 0 116 #define YPSET_LOCAL 1 117 #define YPSET_ALL 2 118 int ypsetmode = YPSET_NO; 119 int ypsecuremode = 0; 120 int ppid; 121 122 /* 123 * Special restricted mode variables: when in restricted mode, only the 124 * specified restricted_domain will be bound, and only the servers listed 125 * in restricted_addrs will be used for binding. 126 */ 127 #define RESTRICTED_SERVERS 10 128 int yp_restricted = 0; 129 int yp_manycast = 0; 130 struct in_addr restricted_addrs[RESTRICTED_SERVERS]; 131 132 /* No more than MAX_CHILDREN child broadcasters at a time. */ 133 #ifndef MAX_CHILDREN 134 #define MAX_CHILDREN 5 135 #endif 136 /* No more than MAX_DOMAINS simultaneous domains */ 137 #ifndef MAX_DOMAINS 138 #define MAX_DOMAINS 200 139 #endif 140 /* RPC timeout value */ 141 #ifndef FAIL_THRESHOLD 142 #define FAIL_THRESHOLD 20 143 #endif 144 145 /* Number of times to fish for a response froma particular set of hosts */ 146 #ifndef MAX_RETRIES 147 #define MAX_RETRIES 30 148 #endif 149 150 int retries = 0; 151 int children = 0; 152 int domains = 0; 153 int yplockfd; 154 fd_set fdsr; 155 156 SVCXPRT *udptransp, *tcptransp; 157 158 void * 159 ypbindproc_null_2_yp(transp, argp, clnt) 160 SVCXPRT *transp; 161 void *argp; 162 CLIENT *clnt; 163 { 164 static char res; 165 166 bzero((char *)&res, sizeof(res)); 167 return (void *)&res; 168 } 169 170 struct ypbind_resp * 171 ypbindproc_domain_2_yp(transp, argp, clnt) 172 SVCXPRT *transp; 173 domainname *argp; 174 CLIENT *clnt; 175 { 176 static struct ypbind_resp res; 177 struct _dom_binding *ypdb; 178 char path[MAXPATHLEN]; 179 180 bzero((char *)&res, sizeof res); 181 res.ypbind_status = YPBIND_FAIL_VAL; 182 res.ypbind_resp_u.ypbind_error = YPBIND_ERR_NOSERV; 183 184 if (strchr(*argp, '/')) { 185 syslog(LOG_WARNING, "Domain name '%s' has embedded slash -- \ 186 rejecting.", *argp); 187 return(&res); 188 } 189 190 for(ypdb=ypbindlist; ypdb; ypdb=ypdb->dom_pnext) { 191 if( strcmp(ypdb->dom_domain, *argp) == 0) 192 break; 193 } 194 195 if(ypdb==NULL) { 196 if (yp_restricted) { 197 syslog(LOG_NOTICE, "Running in restricted mode -- request to bind domain \"%s\" rejected.\n", *argp); 198 return &res; 199 } 200 201 if (domains >= MAX_DOMAINS) { 202 syslog(LOG_WARNING, "domain limit (%d) exceeded", 203 MAX_DOMAINS); 204 res.ypbind_resp_u.ypbind_error = YPBIND_ERR_RESC; 205 return &res; 206 } 207 ypdb = (struct _dom_binding *)malloc(sizeof *ypdb); 208 if (ypdb == NULL) { 209 syslog(LOG_WARNING, "malloc: %m"); 210 res.ypbind_resp_u.ypbind_error = YPBIND_ERR_RESC; 211 return &res; 212 } 213 bzero((char *)ypdb, sizeof *ypdb); 214 strncpy(ypdb->dom_domain, *argp, sizeof ypdb->dom_domain); 215 ypdb->dom_vers = YPVERS; 216 ypdb->dom_alive = 0; 217 ypdb->dom_default = 0; 218 ypdb->dom_lockfd = -1; 219 sprintf(path, "%s/%s.%ld", BINDINGDIR, 220 ypdb->dom_domain, ypdb->dom_vers); 221 unlink(path); 222 ypdb->dom_pnext = ypbindlist; 223 ypbindlist = ypdb; 224 domains++; 225 } 226 227 if (ping(ypdb)) { 228 return &res; 229 } 230 231 res.ypbind_status = YPBIND_SUCC_VAL; 232 res.ypbind_resp_u.ypbind_error = 0; /* Success */ 233 *(u_int32_t *)&res.ypbind_resp_u.ypbind_bindinfo.ypbind_binding_addr = 234 ypdb->dom_server_addr.sin_addr.s_addr; 235 *(u_short *)&res.ypbind_resp_u.ypbind_bindinfo.ypbind_binding_port = 236 ypdb->dom_server_addr.sin_port; 237 /*printf("domain %s at %s/%d\n", ypdb->dom_domain, 238 inet_ntoa(ypdb->dom_server_addr.sin_addr), 239 ntohs(ypdb->dom_server_addr.sin_port));*/ 240 return &res; 241 } 242 243 void * 244 ypbindproc_setdom_2_yp(transp, argp, clnt) 245 SVCXPRT *transp; 246 ypbind_setdom *argp; 247 CLIENT *clnt; 248 { 249 struct sockaddr_in *fromsin, bindsin; 250 static char *result = NULL; 251 252 if (strchr(argp->ypsetdom_domain, '/')) { 253 syslog(LOG_WARNING, "Domain name '%s' has embedded slash -- \ 254 rejecting.", argp->ypsetdom_domain); 255 return(NULL); 256 } 257 fromsin = svc_getcaller(transp); 258 259 switch(ypsetmode) { 260 case YPSET_LOCAL: 261 if( fromsin->sin_addr.s_addr != htonl(INADDR_LOOPBACK)) { 262 svcerr_noprog(transp); 263 return(NULL); 264 } 265 break; 266 case YPSET_ALL: 267 break; 268 case YPSET_NO: 269 default: 270 svcerr_noprog(transp); 271 return(NULL); 272 } 273 274 if(ntohs(fromsin->sin_port) >= IPPORT_RESERVED) { 275 svcerr_noprog(transp); 276 return(NULL); 277 } 278 279 if(argp->ypsetdom_vers != YPVERS) { 280 svcerr_noprog(transp); 281 return(NULL); 282 } 283 284 bzero((char *)&bindsin, sizeof bindsin); 285 bindsin.sin_family = AF_INET; 286 bindsin.sin_addr.s_addr = *(u_int32_t *)argp->ypsetdom_binding.ypbind_binding_addr; 287 bindsin.sin_port = *(u_short *)argp->ypsetdom_binding.ypbind_binding_port; 288 rpc_received(argp->ypsetdom_domain, &bindsin, 1); 289 290 return((void *) &result); 291 } 292 293 static void 294 ypbindprog_2(rqstp, transp) 295 struct svc_req *rqstp; 296 register SVCXPRT *transp; 297 { 298 union { 299 domainname ypbindproc_domain_2_arg; 300 struct ypbind_setdom ypbindproc_setdom_2_arg; 301 } argument; 302 struct authunix_parms *creds; 303 char *result; 304 bool_t (*xdr_argument)(), (*xdr_result)(); 305 char *(*local)(); 306 307 switch (rqstp->rq_proc) { 308 case YPBINDPROC_NULL: 309 xdr_argument = xdr_void; 310 xdr_result = xdr_void; 311 local = (char *(*)()) ypbindproc_null_2_yp; 312 break; 313 314 case YPBINDPROC_DOMAIN: 315 xdr_argument = xdr_domainname; 316 xdr_result = xdr_ypbind_resp; 317 local = (char *(*)()) ypbindproc_domain_2_yp; 318 break; 319 320 case YPBINDPROC_SETDOM: 321 switch(rqstp->rq_cred.oa_flavor) { 322 case AUTH_UNIX: 323 creds = (struct authunix_parms *)rqstp->rq_clntcred; 324 if( creds->aup_uid != 0) { 325 svcerr_auth(transp, AUTH_BADCRED); 326 return; 327 } 328 break; 329 default: 330 svcerr_auth(transp, AUTH_TOOWEAK); 331 return; 332 } 333 334 xdr_argument = xdr_ypbind_setdom; 335 xdr_result = xdr_void; 336 local = (char *(*)()) ypbindproc_setdom_2_yp; 337 break; 338 339 default: 340 svcerr_noproc(transp); 341 return; 342 } 343 bzero((char *)&argument, sizeof(argument)); 344 if (!svc_getargs(transp, xdr_argument, (caddr_t)&argument)) { 345 svcerr_decode(transp); 346 return; 347 } 348 result = (*local)(transp, &argument, rqstp); 349 if (result != NULL && !svc_sendreply(transp, xdr_result, result)) { 350 svcerr_systemerr(transp); 351 } 352 return; 353 } 354 355 /* Jack the reaper */ 356 void reaper(sig) 357 int sig; 358 { 359 int st; 360 361 while(wait3(&st, WNOHANG, NULL) > 0) 362 children--; 363 } 364 365 void terminate(sig) 366 int sig; 367 { 368 struct _dom_binding *ypdb; 369 char path[MAXPATHLEN]; 370 371 if (ppid != getpid()) 372 exit(0); 373 374 for(ypdb=ypbindlist; ypdb; ypdb=ypdb->dom_pnext) { 375 close(ypdb->dom_lockfd); 376 if (ypdb->dom_broadcast_pid) 377 kill(ypdb->dom_broadcast_pid, SIGINT); 378 sprintf(path, "%s/%s.%ld", BINDINGDIR, 379 ypdb->dom_domain, ypdb->dom_vers); 380 unlink(path); 381 } 382 close(yplockfd); 383 unlink(YPBINDLOCK); 384 pmap_unset(YPBINDPROG, YPBINDVERS); 385 exit(0); 386 } 387 388 int 389 main(argc, argv) 390 int argc; 391 char **argv; 392 { 393 struct timeval tv; 394 int i; 395 DIR *dird; 396 struct dirent *dirp; 397 struct _dom_binding *ypdb, *next; 398 399 /* Check that another ypbind isn't already running. */ 400 if ((yplockfd = (open(YPBINDLOCK, O_RDONLY|O_CREAT, 0444))) == -1) 401 err(1, "%s", YPBINDLOCK); 402 403 if(flock(yplockfd, LOCK_EX|LOCK_NB) == -1 && errno == EWOULDBLOCK) 404 errx(1, "another ypbind is already running. Aborting"); 405 406 /* XXX domainname will be overriden if we use restricted mode */ 407 yp_get_default_domain(&domain_name); 408 if( domain_name[0] == '\0') 409 errx(1, "domainname not set. Aborting"); 410 411 for(i=1; i<argc; i++) { 412 if( strcmp("-ypset", argv[i]) == 0) 413 ypsetmode = YPSET_ALL; 414 else if (strcmp("-ypsetme", argv[i]) == 0) 415 ypsetmode = YPSET_LOCAL; 416 else if (strcmp("-s", argv[i]) == 0) 417 ypsecuremode++; 418 else if (strcmp("-S", argv[i]) == 0 && argc > i) 419 yp_restricted_mode(argv[++i]); 420 else if (strcmp("-m", argv[i]) == 0) 421 yp_manycast++; 422 else 423 errx(1, "unknown option: %s", argv[i]); 424 } 425 426 /* blow away everything in BINDINGDIR (if it exists) */ 427 428 if ((dird = opendir(BINDINGDIR)) != NULL) { 429 char path[MAXPATHLEN]; 430 while ((dirp = readdir(dird)) != NULL) 431 if (strcmp(dirp->d_name, ".") && 432 strcmp(dirp->d_name, "..")) { 433 sprintf(path,"%s/%s",BINDINGDIR,dirp->d_name); 434 unlink(path); 435 } 436 closedir(dird); 437 } 438 439 #ifdef DAEMON 440 if (daemon(0,0)) 441 err(1, "fork"); 442 #endif 443 444 pmap_unset(YPBINDPROG, YPBINDVERS); 445 446 udptransp = svcudp_create(RPC_ANYSOCK); 447 if (udptransp == NULL) 448 errx(1, "cannot create udp service"); 449 if (!svc_register(udptransp, YPBINDPROG, YPBINDVERS, ypbindprog_2, 450 IPPROTO_UDP)) 451 errx(1, "unable to register (YPBINDPROG, YPBINDVERS, udp)"); 452 453 tcptransp = svctcp_create(RPC_ANYSOCK, 0, 0); 454 if (tcptransp == NULL) 455 errx(1, "cannot create tcp service"); 456 457 if (!svc_register(tcptransp, YPBINDPROG, YPBINDVERS, ypbindprog_2, 458 IPPROTO_TCP)) 459 errx(1, "unable to register (YPBINDPROG, YPBINDVERS, tcp)"); 460 461 /* build initial domain binding, make it "unsuccessful" */ 462 ypbindlist = (struct _dom_binding *)malloc(sizeof *ypbindlist); 463 if (ypbindlist == NULL) 464 errx(1, "malloc"); 465 bzero((char *)ypbindlist, sizeof *ypbindlist); 466 strncpy(ypbindlist->dom_domain, domain_name, sizeof ypbindlist->dom_domain); 467 ypbindlist->dom_vers = YPVERS; 468 ypbindlist->dom_alive = 0; 469 ypbindlist->dom_lockfd = -1; 470 ypbindlist->dom_default = 1; 471 domains++; 472 473 signal(SIGCHLD, reaper); 474 signal(SIGTERM, terminate); 475 476 ppid = getpid(); /* Remember who we are. */ 477 478 openlog(argv[0], LOG_PID, LOG_DAEMON); 479 480 /* Kick off the default domain */ 481 broadcast(ypbindlist); 482 483 while(1) { 484 fdsr = svc_fdset; 485 486 tv.tv_sec = 60; 487 tv.tv_usec = 0; 488 489 switch(select(_rpc_dtablesize(), &fdsr, NULL, NULL, &tv)) { 490 case 0: 491 checkwork(); 492 break; 493 case -1: 494 if (errno != EINTR) 495 syslog(LOG_WARNING, "select: %m"); 496 break; 497 default: 498 for(ypdb=ypbindlist; ypdb; ypdb=next) { 499 next = ypdb->dom_pnext; 500 if (READFD > 0 && FD_ISSET(READFD, &fdsr)) { 501 handle_children(ypdb); 502 if (children == (MAX_CHILDREN - 1)) 503 checkwork(); 504 } 505 } 506 svc_getreqset(&fdsr); 507 break; 508 } 509 } 510 511 /* NOTREACHED */ 512 exit(1); 513 } 514 515 void 516 checkwork() 517 { 518 struct _dom_binding *ypdb; 519 520 for(ypdb=ypbindlist; ypdb; ypdb=ypdb->dom_pnext) 521 ping(ypdb); 522 } 523 524 /* The clnt_broadcast() callback mechanism sucks. */ 525 526 /* 527 * Receive results from broadcaster. Don't worry about passing 528 * bogus info to rpc_received() -- it can handle it. Note that we 529 * must be sure to invalidate the dom_pipe_fds descriptors here: 530 * since descriptors can be re-used, we have to make sure we 531 * don't mistake one of the RPC descriptors for one of the pipes. 532 * What's weird is that forgetting to invalidate the pipe descriptors 533 * doesn't always result in an error (otherwise I would have caught 534 * the mistake much sooner), even though logically it should. 535 */ 536 void handle_children(ypdb) 537 struct _dom_binding *ypdb; 538 { 539 char buf[YPMAXDOMAIN + 1]; 540 struct sockaddr_in addr; 541 int d = 0, a = 0; 542 struct _dom_binding *y, *prev = NULL; 543 char path[MAXPATHLEN]; 544 545 if ((d = read(READFD, &buf, sizeof(buf))) <= 0) 546 syslog(LOG_WARNING, "could not read from child: %m"); 547 548 if ((a = read(READFD, &addr, sizeof(struct sockaddr_in))) < 0) 549 syslog(LOG_WARNING, "could not read from child: %m"); 550 551 close(READFD); 552 FD_CLR(READFD, &fdsr); 553 FD_CLR(READFD, &svc_fdset); 554 READFD = WRITEFD = -1; 555 if (d > 0 && a > 0) 556 rpc_received((char *)&buf, &addr, 0); 557 else { 558 for(y=ypbindlist; y; y=y->dom_pnext) { 559 if (y == ypdb) 560 break; 561 prev = y; 562 } 563 switch(ypdb->dom_default) { 564 case 0: 565 if (prev == NULL) 566 ypbindlist = y->dom_pnext; 567 else 568 prev->dom_pnext = y->dom_pnext; 569 sprintf(path, "%s/%s.%ld", BINDINGDIR, 570 ypdb->dom_domain, YPVERS); 571 close(ypdb->dom_lockfd); 572 unlink(path); 573 free(ypdb); 574 domains--; 575 return; 576 case 1: 577 ypdb->dom_broadcast_pid = 0; 578 ypdb->dom_alive = 0; 579 broadcast(ypdb); 580 return; 581 default: 582 break; 583 } 584 } 585 586 return; 587 } 588 589 /* 590 * Send our dying words back to our parent before we perish. 591 */ 592 int 593 tell_parent(dom, addr) 594 char *dom; 595 struct sockaddr_in *addr; 596 { 597 char buf[YPMAXDOMAIN + 1]; 598 struct timeval timeout; 599 fd_set fds; 600 601 timeout.tv_sec = 5; 602 timeout.tv_usec = 0; 603 604 sprintf(buf, "%s", broad_domain->dom_domain); 605 if (write(BROADFD, &buf, sizeof(buf)) < 0) 606 return(1); 607 608 /* 609 * Stay in sync with parent: wait for it to read our first 610 * message before sending the second. 611 */ 612 613 FD_ZERO(&fds); 614 FD_SET(BROADFD, &fds); 615 if (select(FD_SETSIZE, NULL, &fds, NULL, &timeout) == -1) 616 return(1); 617 if (FD_ISSET(BROADFD, &fds)) { 618 if (write(BROADFD, addr, sizeof(struct sockaddr_in)) < 0) 619 return(1); 620 } else { 621 return(1); 622 } 623 624 close(BROADFD); 625 return (0); 626 } 627 628 bool_t broadcast_result(out, addr) 629 bool_t *out; 630 struct sockaddr_in *addr; 631 { 632 if (retries >= MAX_RETRIES) { 633 bzero((char *)addr, sizeof(struct sockaddr_in)); 634 if (tell_parent(broad_domain->dom_domain, addr)) 635 syslog(LOG_WARNING, "lost connection to parent"); 636 return TRUE; 637 } 638 639 if (yp_restricted && verify(addr->sin_addr)) { 640 retries++; 641 syslog(LOG_NOTICE, "NIS server at %s not in restricted mode access list -- rejecting.\n",inet_ntoa(addr->sin_addr)); 642 return FALSE; 643 } else { 644 if (tell_parent(broad_domain->dom_domain, addr)) 645 syslog(LOG_WARNING, "lost connection to parent"); 646 return TRUE; 647 } 648 } 649 650 /* 651 * The right way to send RPC broadcasts. 652 * Use the clnt_broadcast() RPC service. Unfortunately, clnt_broadcast() 653 * blocks while waiting for replies, so we have to fork off separate 654 * broadcaster processes that do the waiting and then transmit their 655 * results back to the parent for processing. We also have to remember 656 * to save the name of the domain we're trying to bind in a global 657 * variable since clnt_broadcast() provides no way to pass things to 658 * the 'eachresult' callback function. 659 */ 660 void 661 broadcast(ypdb) 662 struct _dom_binding *ypdb; 663 { 664 bool_t out = FALSE; 665 enum clnt_stat stat; 666 667 if (children >= MAX_CHILDREN || ypdb->dom_broadcast_pid) 668 return; 669 670 if (pipe(ypdb->dom_pipe_fds) < 0) { 671 syslog(LOG_WARNING, "pipe: %m"); 672 return; 673 } 674 675 if (ypdb->dom_vers == -1 && (long)ypdb->dom_server_addr.sin_addr.s_addr) 676 syslog(LOG_WARNING, "NIS server [%s] for domain \"%s\" not responding", 677 inet_ntoa(ypdb->dom_server_addr.sin_addr), ypdb->dom_domain); 678 679 broad_domain = ypdb; 680 flock(ypdb->dom_lockfd, LOCK_UN); 681 682 switch((ypdb->dom_broadcast_pid = fork())) { 683 case 0: 684 close(READFD); 685 signal(SIGCHLD, SIG_DFL); 686 signal(SIGTERM, SIG_DFL); 687 break; 688 case -1: 689 syslog(LOG_WARNING, "fork: %m"); 690 close(READFD); 691 close(WRITEFD); 692 return; 693 default: 694 close(WRITEFD); 695 FD_SET(READFD, &svc_fdset); 696 children++; 697 return; 698 } 699 700 /* Release all locks before doing anything else. */ 701 while(ypbindlist) { 702 close(ypbindlist->dom_lockfd); 703 ypbindlist = ypbindlist->dom_pnext; 704 } 705 close(yplockfd); 706 707 /* 708 * Special 'many-cast' behavior. If we're in restricted mode, 709 * we have a list of possible server addresses to try. What 710 * we can do is transmit to each ypserv's YPPROC_DOMAIN_NONACK 711 * procedure and time the replies. Whoever replies fastest 712 * gets to be our server. Note that this is not a broadcast 713 * operation: we transmit uni-cast datagrams only. 714 */ 715 if (yp_restricted && yp_manycast) { 716 short port; 717 int i; 718 struct sockaddr_in sin; 719 720 i = __yp_ping(restricted_addrs, yp_restricted, 721 ypdb->dom_domain, &port); 722 if (i == -1) { 723 bzero((char *)&ypdb->dom_server_addr, 724 sizeof(struct sockaddr_in)); 725 if (tell_parent(ypdb->dom_domain, 726 &ypdb->dom_server_addr)) 727 syslog(LOG_WARNING, "lost connection to parent"); 728 } else { 729 bzero((char *)&sin, sizeof(struct sockaddr_in)); 730 bcopy((char *)&restricted_addrs[i], 731 (char *)&sin.sin_addr, sizeof(struct in_addr)); 732 sin.sin_family = AF_INET; 733 sin.sin_port = port; 734 if (tell_parent(broad_domain->dom_domain, &sin)) 735 syslog(LOG_WARNING, 736 "lost connection to parent"); 737 } 738 _exit(0); 739 } 740 741 retries = 0; 742 743 { 744 char *ptr; 745 746 ptr = (char *)&ypdb->dom_domain; 747 stat = clnt_broadcast(YPPROG, YPVERS, YPPROC_DOMAIN_NONACK, 748 xdr_domainname, (char *)&ptr, xdr_bool, (char *)&out, 749 (resultproc_t)broadcast_result); 750 } 751 752 if (stat != RPC_SUCCESS) { 753 bzero((char *)&ypdb->dom_server_addr, 754 sizeof(struct sockaddr_in)); 755 if (tell_parent(ypdb->dom_domain, &ypdb->dom_server_addr)) 756 syslog(LOG_WARNING, "lost connection to parent"); 757 } 758 759 _exit(0); 760 } 761 762 /* 763 * The right way to check if a server is alive. 764 * Attempt to get a client handle pointing to the server and send a 765 * YPPROC_DOMAIN. If we can't get a handle or we get a reply of FALSE, 766 * we invalidate this binding entry and send out a broadcast to try to 767 * establish a new binding. Note that we treat non-default domains 768 * specially: once bound, we keep tabs on our server, but if it 769 * goes away and fails to respond after one round of broadcasting, we 770 * abandon it until a client specifically references it again. We make 771 * every effort to keep our default domain bound, however, since we 772 * need it to keep the system on its feet. 773 */ 774 int 775 ping(ypdb) 776 struct _dom_binding *ypdb; 777 { 778 bool_t out; 779 struct timeval interval, timeout; 780 enum clnt_stat stat; 781 int rpcsock = RPC_ANYSOCK; 782 CLIENT *client_handle; 783 784 interval.tv_sec = FAIL_THRESHOLD; 785 interval.tv_usec = 0; 786 timeout.tv_sec = FAIL_THRESHOLD; 787 timeout.tv_usec = 0; 788 789 if (ypdb->dom_broadcast_pid) 790 return(1); 791 792 if ((client_handle = clntudp_bufcreate(&ypdb->dom_server_addr, 793 YPPROG, YPVERS, interval, &rpcsock, RPCSMALLMSGSIZE, 794 RPCSMALLMSGSIZE)) == (CLIENT *)NULL) { 795 /* Can't get a handle: we're dead. */ 796 ypdb->dom_alive = 0; 797 ypdb->dom_vers = -1; 798 broadcast(ypdb); 799 return(1); 800 } 801 802 { 803 char *ptr; 804 805 ptr = (char *)&ypdb->dom_domain; 806 807 if ((stat = clnt_call(client_handle, YPPROC_DOMAIN, 808 xdr_domainname, (char *)&ptr, xdr_bool, (char *)&out, 809 timeout)) != RPC_SUCCESS || out == FALSE) { 810 ypdb->dom_alive = 0; 811 ypdb->dom_vers = -1; 812 clnt_destroy(client_handle); 813 broadcast(ypdb); 814 return(1); 815 } 816 } 817 818 clnt_destroy(client_handle); 819 return(0); 820 } 821 822 void rpc_received(dom, raddrp, force) 823 char *dom; 824 struct sockaddr_in *raddrp; 825 int force; 826 { 827 struct _dom_binding *ypdb, *prev = NULL; 828 struct iovec iov[2]; 829 struct ypbind_resp ybr; 830 char path[MAXPATHLEN]; 831 int fd; 832 833 /*printf("returned from %s/%d about %s\n", inet_ntoa(raddrp->sin_addr), 834 ntohs(raddrp->sin_port), dom);*/ 835 836 if(dom==NULL) 837 return; 838 839 for(ypdb=ypbindlist; ypdb; ypdb=ypdb->dom_pnext) { 840 if( strcmp(ypdb->dom_domain, dom) == 0) 841 break; 842 prev = ypdb; 843 } 844 845 if (ypdb && force) { 846 if (ypdb->dom_broadcast_pid) { 847 kill(ypdb->dom_broadcast_pid, SIGINT); 848 close(READFD); 849 FD_CLR(READFD, &fdsr); 850 FD_CLR(READFD, &svc_fdset); 851 READFD = WRITEFD = -1; 852 } 853 } 854 855 /* if in secure mode, check originating port number */ 856 if ((ypsecuremode && (ntohs(raddrp->sin_port) >= IPPORT_RESERVED))) { 857 syslog(LOG_WARNING, "Rejected NIS server on [%s/%d] for domain %s.", 858 inet_ntoa(raddrp->sin_addr), ntohs(raddrp->sin_port), 859 dom); 860 if (ypdb != NULL) { 861 ypdb->dom_broadcast_pid = 0; 862 ypdb->dom_alive = 0; 863 } 864 return; 865 } 866 867 if (raddrp->sin_addr.s_addr == (long)0) { 868 switch(ypdb->dom_default) { 869 case 0: 870 if (prev == NULL) 871 ypbindlist = ypdb->dom_pnext; 872 else 873 prev->dom_pnext = ypdb->dom_pnext; 874 sprintf(path, "%s/%s.%ld", BINDINGDIR, 875 ypdb->dom_domain, YPVERS); 876 close(ypdb->dom_lockfd); 877 unlink(path); 878 free(ypdb); 879 domains--; 880 return; 881 case 1: 882 ypdb->dom_broadcast_pid = 0; 883 ypdb->dom_alive = 0; 884 broadcast(ypdb); 885 return; 886 default: 887 break; 888 } 889 } 890 891 if(ypdb==NULL) { 892 if (force == 0) 893 return; 894 ypdb = (struct _dom_binding *)malloc(sizeof *ypdb); 895 if (ypdb == NULL) { 896 syslog(LOG_WARNING, "malloc: %m"); 897 return; 898 } 899 bzero((char *)ypdb, sizeof *ypdb); 900 strncpy(ypdb->dom_domain, dom, sizeof ypdb->dom_domain); 901 ypdb->dom_lockfd = -1; 902 ypdb->dom_default = 0; 903 ypdb->dom_pnext = ypbindlist; 904 ypbindlist = ypdb; 905 } 906 907 /* We've recovered from a crash: inform the world. */ 908 if (ypdb->dom_vers == -1 && ypdb->dom_server_addr.sin_addr.s_addr) 909 syslog(LOG_WARNING, "NIS server [%s] for domain \"%s\" OK", 910 inet_ntoa(raddrp->sin_addr), ypdb->dom_domain); 911 912 bcopy((char *)raddrp, (char *)&ypdb->dom_server_addr, 913 sizeof ypdb->dom_server_addr); 914 915 ypdb->dom_vers = YPVERS; 916 ypdb->dom_alive = 1; 917 ypdb->dom_broadcast_pid = 0; 918 919 if(ypdb->dom_lockfd != -1) 920 close(ypdb->dom_lockfd); 921 922 sprintf(path, "%s/%s.%ld", BINDINGDIR, 923 ypdb->dom_domain, ypdb->dom_vers); 924 #ifdef O_SHLOCK 925 if( (fd=open(path, O_CREAT|O_SHLOCK|O_RDWR|O_TRUNC, 0644)) == -1) { 926 (void)mkdir(BINDINGDIR, 0755); 927 if( (fd=open(path, O_CREAT|O_SHLOCK|O_RDWR|O_TRUNC, 0644)) == -1) 928 return; 929 } 930 #else 931 if( (fd=open(path, O_CREAT|O_RDWR|O_TRUNC, 0644)) == -1) { 932 (void)mkdir(BINDINGDIR, 0755); 933 if( (fd=open(path, O_CREAT|O_RDWR|O_TRUNC, 0644)) == -1) 934 return; 935 } 936 flock(fd, LOCK_SH); 937 #endif 938 939 /* 940 * ok, if BINDINGDIR exists, and we can create the binding file, 941 * then write to it.. 942 */ 943 ypdb->dom_lockfd = fd; 944 945 iov[0].iov_base = (caddr_t)&(udptransp->xp_port); 946 iov[0].iov_len = sizeof udptransp->xp_port; 947 iov[1].iov_base = (caddr_t)&ybr; 948 iov[1].iov_len = sizeof ybr; 949 950 bzero(&ybr, sizeof ybr); 951 ybr.ypbind_status = YPBIND_SUCC_VAL; 952 *(u_int32_t *)&ybr.ypbind_resp_u.ypbind_bindinfo.ypbind_binding_addr = raddrp->sin_addr.s_addr; 953 *(u_short *)&ybr.ypbind_resp_u.ypbind_bindinfo.ypbind_binding_port = raddrp->sin_port; 954 955 if( writev(ypdb->dom_lockfd, iov, 2) != iov[0].iov_len + iov[1].iov_len) { 956 syslog(LOG_WARNING, "write: %m"); 957 close(ypdb->dom_lockfd); 958 ypdb->dom_lockfd = -1; 959 return; 960 } 961 } 962 963 /* 964 * Check address against list of allowed servers. Return 0 if okay, 965 * 1 if not matched. 966 */ 967 int 968 verify(addr) 969 struct in_addr addr; 970 { 971 int i; 972 973 for (i = 0; i < RESTRICTED_SERVERS; i++) 974 if (!bcmp((char *)&addr, (char *)&restricted_addrs[i], 975 sizeof(struct in_addr))) 976 return(0); 977 978 return(1); 979 } 980 981 /* 982 * Try to set restricted mode. We default to normal mode if we can't 983 * resolve the specified hostnames. 984 */ 985 void 986 yp_restricted_mode(args) 987 char *args; 988 { 989 struct hostent *h; 990 int i = 0; 991 char *s; 992 993 /* Find the restricted domain. */ 994 if ((s = strsep(&args, ",")) == NULL) 995 return; 996 domain_name = s; 997 998 /* Get the addresses of the servers. */ 999 while ((s = strsep(&args, ",")) != NULL && i < RESTRICTED_SERVERS) { 1000 if ((h = gethostbyname(s)) == NULL) 1001 return; 1002 bcopy ((char *)h->h_addr_list[0], (char *)&restricted_addrs[i], 1003 sizeof(struct in_addr)); 1004 i++; 1005 } 1006 1007 /* ypset and ypsetme not allowed with restricted mode */ 1008 ypsetmode = YPSET_NO; 1009 1010 yp_restricted = i; 1011 return; 1012 } 1013