1 /* $NetBSD: ypbind.c,v 1.57 2007/07/07 22:33:57 christos Exp $ */ 2 3 /* 4 * Copyright (c) 1992, 1993 Theo de Raadt <deraadt@fsa.ca> 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS 17 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 18 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY 20 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 #include <sys/cdefs.h> 30 #ifndef LINT 31 __RCSID("$NetBSD: ypbind.c,v 1.57 2007/07/07 22:33:57 christos Exp $"); 32 #endif 33 34 #include <sys/param.h> 35 #include <sys/types.h> 36 #include <sys/ioctl.h> 37 #include <sys/signal.h> 38 #include <sys/socket.h> 39 #include <sys/file.h> 40 #include <sys/uio.h> 41 #include <sys/syslog.h> 42 #include <sys/stat.h> 43 #include <fcntl.h> 44 #include <limits.h> 45 #include <stdio.h> 46 #include <stdlib.h> 47 #include <errno.h> 48 #include <syslog.h> 49 #include <stdarg.h> 50 #include <ctype.h> 51 #include <dirent.h> 52 #include <netdb.h> 53 #include <string.h> 54 #include <err.h> 55 #include <rpc/rpc.h> 56 #include <rpc/xdr.h> 57 #include <net/if.h> 58 #include <arpa/inet.h> 59 #include <rpc/pmap_clnt.h> 60 #include <rpc/pmap_prot.h> 61 #include <rpc/pmap_rmt.h> 62 #include <unistd.h> 63 #include <util.h> 64 #include <rpcsvc/yp_prot.h> 65 #include <rpcsvc/ypclnt.h> 66 #include <ifaddrs.h> 67 68 #include "pathnames.h" 69 70 #ifndef O_SHLOCK 71 #define O_SHLOCK 0 72 #endif 73 74 #define BUFSIZE 1400 75 76 #define YPSERVERSSUFF ".ypservers" 77 #define BINDINGDIR (_PATH_VAR_YP "binding") 78 79 struct _dom_binding { 80 struct _dom_binding *dom_pnext; 81 char dom_domain[YPMAXDOMAIN + 1]; 82 struct sockaddr_in dom_server_addr; 83 int dom_socket; 84 CLIENT *dom_client; 85 long dom_vers; 86 time_t dom_check_t; 87 time_t dom_ask_t; 88 int dom_lockfd; 89 int dom_alive; 90 u_int32_t dom_xid; 91 }; 92 93 static char *domainname; 94 95 static struct _dom_binding *ypbindlist; 96 static int check; 97 98 typedef enum { 99 YPBIND_DIRECT, YPBIND_BROADCAST, YPBIND_SETLOCAL, YPBIND_SETALL 100 } ypbind_mode_t; 101 102 ypbind_mode_t ypbindmode; 103 104 /* 105 * If ypbindmode is YPBIND_SETLOCAL or YPBIND_SETALL, this indicates 106 * whether or not we've been "ypset". If we haven't, we behave like 107 * YPBIND_BROADCAST. If we have, we behave like YPBIND_DIRECT. 108 */ 109 int been_ypset; 110 111 #ifdef DEBUG 112 static int debug; 113 #endif 114 115 static int insecure; 116 static int rpcsock, pingsock; 117 static struct rmtcallargs rmtca; 118 static struct rmtcallres rmtcr; 119 static bool_t rmtcr_outval; 120 static u_long rmtcr_port; 121 static SVCXPRT *udptransp, *tcptransp; 122 123 int _yp_invalid_domain(const char *); /* from libc */ 124 int main(int, char *[]); 125 126 static void usage(void); 127 static void yp_log(int, const char *, ...) 128 __attribute__((__format__(__printf__, 2, 3))); 129 static struct _dom_binding *makebinding(const char *); 130 static int makelock(struct _dom_binding *); 131 static void removelock(struct _dom_binding *); 132 static void *ypbindproc_null_2(SVCXPRT *, void *); 133 static void *ypbindproc_domain_2(SVCXPRT *, void *); 134 static void *ypbindproc_setdom_2(SVCXPRT *, void *); 135 static void ypbindprog_2(struct svc_req *, SVCXPRT *); 136 static void checkwork(void); 137 static int ping(struct _dom_binding *); 138 static int nag_servers(struct _dom_binding *); 139 static enum clnt_stat handle_replies(void); 140 static enum clnt_stat handle_ping(void); 141 static void rpc_received(char *, struct sockaddr_in *, int); 142 static struct _dom_binding *xid2ypdb(u_int32_t); 143 static u_int32_t unique_xid(struct _dom_binding *); 144 static int broadcast(char *, int); 145 static int direct(char *, int); 146 static int direct_set(char *, int, struct _dom_binding *); 147 148 static void 149 usage(void) 150 { 151 const char *opt = ""; 152 #ifdef DEBUG 153 opt = " [-d]"; 154 #endif 155 156 (void)fprintf(stderr, 157 "Usage: %s [-broadcast] [-insecure] [-ypset] [-ypsetme]%s\n", 158 getprogname(), opt); 159 exit(1); 160 } 161 162 static void 163 yp_log(int pri, const char *fmt, ...) 164 { 165 va_list ap; 166 167 va_start(ap, fmt); 168 169 #if defined(DEBUG) 170 if (debug) 171 (void)vprintf(fmt, ap); 172 else 173 #endif 174 vsyslog(pri, fmt, ap); 175 va_end(ap); 176 } 177 178 static struct _dom_binding * 179 makebinding(const char *dm) 180 { 181 struct _dom_binding *ypdb; 182 183 if ((ypdb = (struct _dom_binding *)malloc(sizeof *ypdb)) == NULL) { 184 yp_log(LOG_ERR, "makebinding"); 185 exit(1); 186 } 187 188 (void)memset(ypdb, 0, sizeof *ypdb); 189 (void)strlcpy(ypdb->dom_domain, dm, sizeof ypdb->dom_domain); 190 return ypdb; 191 } 192 193 static int 194 makelock(struct _dom_binding *ypdb) 195 { 196 int fd; 197 char path[MAXPATHLEN]; 198 199 (void)snprintf(path, sizeof(path), "%s/%s.%ld", BINDINGDIR, 200 ypdb->dom_domain, ypdb->dom_vers); 201 202 if ((fd = open(path, O_CREAT|O_SHLOCK|O_RDWR|O_TRUNC, 0644)) == -1) { 203 (void)mkdir(BINDINGDIR, 0755); 204 if ((fd = open(path, O_CREAT|O_SHLOCK|O_RDWR|O_TRUNC, 0644)) == -1) 205 return -1; 206 } 207 208 #if O_SHLOCK == 0 209 (void)flock(fd, LOCK_SH); 210 #endif 211 return fd; 212 } 213 214 static void 215 removelock(struct _dom_binding *ypdb) 216 { 217 char path[MAXPATHLEN]; 218 219 (void)snprintf(path, sizeof(path), "%s/%s.%ld", 220 BINDINGDIR, ypdb->dom_domain, ypdb->dom_vers); 221 (void)unlink(path); 222 } 223 224 static void * 225 /*ARGSUSED*/ 226 ypbindproc_null_2(SVCXPRT *transp, void *argp) 227 { 228 static char res; 229 230 #ifdef DEBUG 231 if (debug) 232 (void)printf("ypbindproc_null_2\n"); 233 #endif 234 (void)memset(&res, 0, sizeof(res)); 235 return (void *)&res; 236 } 237 238 static void * 239 /*ARGSUSED*/ 240 ypbindproc_domain_2(SVCXPRT *transp, void *argp) 241 { 242 static struct ypbind_resp res; 243 struct _dom_binding *ypdb; 244 char *arg = *(char **) argp; 245 time_t now; 246 int count; 247 248 #ifdef DEBUG 249 if (debug) 250 (void)printf("ypbindproc_domain_2 %s\n", arg); 251 #endif 252 if (_yp_invalid_domain(arg)) 253 return NULL; 254 255 (void)memset(&res, 0, sizeof res); 256 res.ypbind_status = YPBIND_FAIL_VAL; 257 258 for (count = 0, ypdb = ypbindlist; 259 ypdb != NULL; 260 ypdb = ypdb->dom_pnext, count++) { 261 if (count > 100) 262 return NULL; /* prevent denial of service */ 263 if (!strcmp(ypdb->dom_domain, arg)) 264 break; 265 } 266 267 if (ypdb == NULL) { 268 ypdb = makebinding(arg); 269 ypdb->dom_vers = YPVERS; 270 ypdb->dom_alive = 0; 271 ypdb->dom_lockfd = -1; 272 removelock(ypdb); 273 ypdb->dom_xid = unique_xid(ypdb); 274 ypdb->dom_pnext = ypbindlist; 275 ypbindlist = ypdb; 276 check++; 277 #ifdef DEBUG 278 if (debug) 279 (void)printf("unknown domain %s\n", arg); 280 #endif 281 return NULL; 282 } 283 284 if (ypdb->dom_alive == 0) { 285 #ifdef DEBUG 286 if (debug) 287 (void)printf("dead domain %s\n", arg); 288 #endif 289 return NULL; 290 } 291 292 #ifdef HEURISTIC 293 (void)time(&now); 294 if (now < ypdb->dom_ask_t + 5) { 295 /* 296 * Hmm. More than 2 requests in 5 seconds have indicated 297 * that my binding is possibly incorrect. 298 * Ok, do an immediate poll of the server. 299 */ 300 if (ypdb->dom_check_t >= now) { 301 /* don't flood it */ 302 ypdb->dom_check_t = 0; 303 check++; 304 } 305 } 306 ypdb->dom_ask_t = now; 307 #endif 308 309 res.ypbind_status = YPBIND_SUCC_VAL; 310 res.ypbind_respbody.ypbind_bindinfo.ypbind_binding_addr.s_addr = 311 ypdb->dom_server_addr.sin_addr.s_addr; 312 res.ypbind_respbody.ypbind_bindinfo.ypbind_binding_port = 313 ypdb->dom_server_addr.sin_port; 314 #ifdef DEBUG 315 if (debug) 316 (void)printf("domain %s at %s/%d\n", ypdb->dom_domain, 317 inet_ntoa(ypdb->dom_server_addr.sin_addr), 318 ntohs(ypdb->dom_server_addr.sin_port)); 319 #endif 320 return &res; 321 } 322 323 static void * 324 ypbindproc_setdom_2(SVCXPRT *transp, void *argp) 325 { 326 struct ypbind_setdom *sd = argp; 327 struct sockaddr_in *fromsin, bindsin; 328 static bool_t res; 329 330 #ifdef DEBUG 331 if (debug) 332 (void)printf("ypbindproc_setdom_2 %s\n", inet_ntoa(bindsin.sin_addr)); 333 #endif 334 (void)memset(&res, 0, sizeof(res)); 335 fromsin = svc_getcaller(transp); 336 337 switch (ypbindmode) { 338 case YPBIND_SETLOCAL: 339 if (fromsin->sin_addr.s_addr != htonl(INADDR_LOOPBACK)) { 340 #ifdef DEBUG 341 if (debug) 342 (void)printf("ypset from %s denied\n", 343 inet_ntoa(fromsin->sin_addr)); 344 #endif 345 return NULL; 346 } 347 /* FALLTHROUGH */ 348 349 case YPBIND_SETALL: 350 been_ypset = 1; 351 break; 352 353 case YPBIND_DIRECT: 354 case YPBIND_BROADCAST: 355 default: 356 #ifdef DEBUG 357 if (debug) 358 (void)printf("ypset denied\n"); 359 #endif 360 return NULL; 361 } 362 363 if (ntohs(fromsin->sin_port) >= IPPORT_RESERVED) { 364 #ifdef DEBUG 365 if (debug) 366 (void)printf("ypset from unprivileged port denied\n"); 367 #endif 368 return &res; 369 } 370 371 if (sd->ypsetdom_vers != YPVERS) { 372 #ifdef DEBUG 373 if (debug) 374 (void)printf("ypset with wrong version denied\n"); 375 #endif 376 return &res; 377 } 378 379 (void)memset(&bindsin, 0, sizeof bindsin); 380 bindsin.sin_family = AF_INET; 381 bindsin.sin_len = sizeof(bindsin); 382 bindsin.sin_addr = sd->ypsetdom_addr; 383 bindsin.sin_port = sd->ypsetdom_port; 384 rpc_received(sd->ypsetdom_domain, &bindsin, 1); 385 386 #ifdef DEBUG 387 if (debug) 388 (void)printf("ypset to %s succeeded\n", inet_ntoa(bindsin.sin_addr)); 389 #endif 390 res = 1; 391 return &res; 392 } 393 394 static void 395 ypbindprog_2(struct svc_req *rqstp, register SVCXPRT *transp) 396 { 397 union { 398 char ypbindproc_domain_2_arg[YPMAXDOMAIN + 1]; 399 struct ypbind_setdom ypbindproc_setdom_2_arg; 400 void *alignment; 401 } argument; 402 struct authunix_parms *creds; 403 char *result; 404 xdrproc_t xdr_argument, xdr_result; 405 void *(*local)(SVCXPRT *, void *); 406 407 switch (rqstp->rq_proc) { 408 case YPBINDPROC_NULL: 409 xdr_argument = xdr_void; 410 xdr_result = xdr_void; 411 local = ypbindproc_null_2; 412 break; 413 414 case YPBINDPROC_DOMAIN: 415 xdr_argument = xdr_ypdomain_wrap_string; 416 xdr_result = xdr_ypbind_resp; 417 local = ypbindproc_domain_2; 418 break; 419 420 case YPBINDPROC_SETDOM: 421 switch (rqstp->rq_cred.oa_flavor) { 422 case AUTH_UNIX: 423 creds = (struct authunix_parms *)rqstp->rq_clntcred; 424 if (creds->aup_uid != 0) { 425 svcerr_auth(transp, AUTH_BADCRED); 426 return; 427 } 428 break; 429 default: 430 svcerr_auth(transp, AUTH_TOOWEAK); 431 return; 432 } 433 434 xdr_argument = xdr_ypbind_setdom; 435 xdr_result = xdr_void; 436 local = ypbindproc_setdom_2; 437 break; 438 439 default: 440 svcerr_noproc(transp); 441 return; 442 } 443 (void)memset(&argument, 0, sizeof(argument)); 444 if (!svc_getargs(transp, xdr_argument, (caddr_t)(void *)&argument)) { 445 svcerr_decode(transp); 446 return; 447 } 448 result = (*local)(transp, &argument); 449 if (result != NULL && !svc_sendreply(transp, xdr_result, result)) { 450 svcerr_systemerr(transp); 451 } 452 return; 453 } 454 455 int 456 main(int argc, char *argv[]) 457 { 458 struct timeval tv; 459 fd_set fdsr; 460 int width, lockfd; 461 int evil = 0, one; 462 char pathname[MAXPATHLEN]; 463 struct stat st; 464 465 setprogname(argv[0]); 466 (void)yp_get_default_domain(&domainname); 467 if (domainname[0] == '\0') 468 errx(1, "Domainname not set. Aborting."); 469 470 /* 471 * Per traditional ypbind(8) semantics, if a ypservers 472 * file does not exist, we default to broadcast mode. 473 * If the file does exist, we default to direct mode. 474 * Note that we can still override direct mode by passing 475 * the -broadcast flag. 476 */ 477 (void)snprintf(pathname, sizeof(pathname), "%s/%s%s", BINDINGDIR, 478 domainname, YPSERVERSSUFF); 479 if (stat(pathname, &st) < 0) { 480 #ifdef DEBUG 481 if (debug) 482 (void)printf("%s does not exist, defaulting to " 483 "broadcast\n", pathname); 484 #endif 485 ypbindmode = YPBIND_BROADCAST; 486 } else 487 ypbindmode = YPBIND_DIRECT; 488 489 while (--argc) { 490 ++argv; 491 if (!strcmp("-insecure", *argv)) 492 insecure = 1; 493 else if (!strcmp("-ypset", *argv)) 494 ypbindmode = YPBIND_SETALL; 495 else if (!strcmp("-ypsetme", *argv)) 496 ypbindmode = YPBIND_SETLOCAL; 497 else if (!strcmp("-broadcast", *argv)) 498 ypbindmode = YPBIND_BROADCAST; 499 #ifdef DEBUG 500 else if (!strcmp("-d", *argv)) 501 debug++; 502 #endif 503 else 504 usage(); 505 } 506 507 /* initialise syslog */ 508 openlog("ypbind", LOG_PERROR | LOG_PID, LOG_DAEMON); 509 510 /* blow away everything in BINDINGDIR */ 511 512 lockfd = open(_PATH_YPBIND_LOCK, O_CREAT|O_SHLOCK|O_RDWR|O_TRUNC, 0644); 513 if (lockfd == -1) 514 err(1, "Cannot create %s", _PATH_YPBIND_LOCK); 515 516 #if O_SHLOCK == 0 517 (void)flock(lockfd, LOCK_SH); 518 #endif 519 520 (void)pmap_unset(YPBINDPROG, YPBINDVERS); 521 522 udptransp = svcudp_create(RPC_ANYSOCK); 523 if (udptransp == NULL) 524 errx(1, "Cannot create udp service."); 525 526 if (!svc_register(udptransp, YPBINDPROG, YPBINDVERS, ypbindprog_2, 527 IPPROTO_UDP)) 528 errx(1, "Unable to register (YPBINDPROG, YPBINDVERS, udp)."); 529 530 tcptransp = svctcp_create(RPC_ANYSOCK, 0, 0); 531 if (tcptransp == NULL) 532 errx(1, "Cannot create tcp service."); 533 534 if (!svc_register(tcptransp, YPBINDPROG, YPBINDVERS, ypbindprog_2, 535 IPPROTO_TCP)) 536 errx(1, "Unable to register (YPBINDPROG, YPBINDVERS, tcp)."); 537 538 /* XXX use SOCK_STREAM for direct queries? */ 539 if ((rpcsock = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP)) == -1) 540 err(1, "rpc socket"); 541 if ((pingsock = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP)) == -1) 542 err(1, "ping socket"); 543 544 (void)fcntl(rpcsock, F_SETFL, fcntl(rpcsock, F_GETFL, 0) | FNDELAY); 545 (void)fcntl(pingsock, F_SETFL, fcntl(pingsock, F_GETFL, 0) | FNDELAY); 546 547 one = 1; 548 (void)setsockopt(rpcsock, SOL_SOCKET, SO_BROADCAST, &one, 549 (socklen_t)sizeof(one)); 550 rmtca.prog = YPPROG; 551 rmtca.vers = YPVERS; 552 rmtca.proc = YPPROC_DOMAIN_NONACK; 553 rmtca.xdr_args = NULL; /* set at call time */ 554 rmtca.args_ptr = NULL; /* set at call time */ 555 rmtcr.port_ptr = &rmtcr_port; 556 rmtcr.xdr_results = xdr_bool; 557 rmtcr.results_ptr = (caddr_t)(void *)&rmtcr_outval; 558 559 if (_yp_invalid_domain(domainname)) 560 errx(1, "bad domainname: %s", domainname); 561 562 /* build initial domain binding, make it "unsuccessful" */ 563 ypbindlist = makebinding(domainname); 564 ypbindlist->dom_vers = YPVERS; 565 ypbindlist->dom_alive = 0; 566 ypbindlist->dom_lockfd = -1; 567 removelock(ypbindlist); 568 569 checkwork(); 570 571 for (;;) { 572 width = svc_maxfd; 573 if (rpcsock > width) 574 width = rpcsock; 575 if (pingsock > width) 576 width = pingsock; 577 width++; 578 fdsr = svc_fdset; 579 FD_SET(rpcsock, &fdsr); 580 FD_SET(pingsock, &fdsr); 581 tv.tv_sec = 1; 582 tv.tv_usec = 0; 583 584 switch (select(width, &fdsr, NULL, NULL, &tv)) { 585 case 0: 586 checkwork(); 587 break; 588 case -1: 589 yp_log(LOG_WARNING, "select: %m"); 590 break; 591 default: 592 if (FD_ISSET(rpcsock, &fdsr)) 593 (void)handle_replies(); 594 if (FD_ISSET(pingsock, &fdsr)) 595 (void)handle_ping(); 596 svc_getreqset(&fdsr); 597 if (check) 598 checkwork(); 599 break; 600 } 601 602 if (!evil && ypbindlist->dom_alive) { 603 evil = 1; 604 #ifdef DEBUG 605 if (!debug) 606 #endif 607 (void)daemon(0, 0); 608 (void)pidfile(NULL); 609 } 610 } 611 } 612 613 /* 614 * State transition is done like this: 615 * 616 * STATE EVENT ACTION NEWSTATE TIMEOUT 617 * no binding timeout broadcast no binding 5 sec 618 * no binding answer -- binding 60 sec 619 * binding timeout ping server checking 5 sec 620 * checking timeout ping server + broadcast checking 5 sec 621 * checking answer -- binding 60 sec 622 */ 623 void 624 checkwork(void) 625 { 626 struct _dom_binding *ypdb; 627 time_t t; 628 629 check = 0; 630 631 (void)time(&t); 632 for (ypdb = ypbindlist; ypdb; ypdb = ypdb->dom_pnext) { 633 if (ypdb->dom_check_t < t) { 634 if (ypdb->dom_alive == 1) 635 (void)ping(ypdb); 636 else 637 (void)nag_servers(ypdb); 638 (void)time(&t); 639 ypdb->dom_check_t = t + 5; 640 } 641 } 642 } 643 644 int 645 ping(struct _dom_binding *ypdb) 646 { 647 char *dom = ypdb->dom_domain; 648 struct rpc_msg msg; 649 char buf[BUFSIZE]; 650 enum clnt_stat st; 651 int outlen; 652 AUTH *rpcua; 653 XDR xdr; 654 655 (void)memset(&xdr, 0, sizeof xdr); 656 (void)memset(&msg, 0, sizeof msg); 657 658 rpcua = authunix_create_default(); 659 if (rpcua == NULL) { 660 #ifdef DEBUG 661 if (debug) 662 (void)printf("cannot get unix auth\n"); 663 #endif 664 return RPC_SYSTEMERROR; 665 } 666 667 msg.rm_direction = CALL; 668 msg.rm_call.cb_rpcvers = RPC_MSG_VERSION; 669 msg.rm_call.cb_prog = YPPROG; 670 msg.rm_call.cb_vers = YPVERS; 671 msg.rm_call.cb_proc = YPPROC_DOMAIN_NONACK; 672 msg.rm_call.cb_cred = rpcua->ah_cred; 673 msg.rm_call.cb_verf = rpcua->ah_verf; 674 675 msg.rm_xid = ypdb->dom_xid; 676 xdrmem_create(&xdr, buf, (u_int)sizeof(buf), XDR_ENCODE); 677 if (!xdr_callmsg(&xdr, &msg)) { 678 st = RPC_CANTENCODEARGS; 679 AUTH_DESTROY(rpcua); 680 return st; 681 } 682 if (!xdr_ypdomain_wrap_string(&xdr, &dom)) { 683 st = RPC_CANTENCODEARGS; 684 AUTH_DESTROY(rpcua); 685 return st; 686 } 687 outlen = (int)xdr_getpos(&xdr); 688 xdr_destroy(&xdr); 689 if (outlen < 1) { 690 st = RPC_CANTENCODEARGS; 691 AUTH_DESTROY(rpcua); 692 return st; 693 } 694 AUTH_DESTROY(rpcua); 695 696 ypdb->dom_alive = 2; 697 #ifdef DEBUG 698 if (debug) 699 (void)printf("ping %x\n", 700 ypdb->dom_server_addr.sin_addr.s_addr); 701 #endif 702 if (sendto(pingsock, buf, outlen, 0, 703 (struct sockaddr *)(void *)&ypdb->dom_server_addr, 704 (socklen_t)sizeof ypdb->dom_server_addr) == -1) 705 yp_log(LOG_WARNING, "ping: sendto: %m"); 706 return 0; 707 708 } 709 710 static int 711 nag_servers(struct _dom_binding *ypdb) 712 { 713 char *dom = ypdb->dom_domain; 714 struct rpc_msg msg; 715 char buf[BUFSIZE]; 716 enum clnt_stat st; 717 int outlen; 718 AUTH *rpcua; 719 XDR xdr; 720 721 #ifdef DEBUG 722 if (debug) 723 (void)printf("nag_servers\n"); 724 #endif 725 rmtca.xdr_args = xdr_ypdomain_wrap_string; 726 rmtca.args_ptr = (caddr_t)(void *)&dom; 727 728 (void)memset(&xdr, 0, sizeof xdr); 729 (void)memset(&msg, 0, sizeof msg); 730 731 rpcua = authunix_create_default(); 732 if (rpcua == NULL) { 733 #ifdef DEBUG 734 if (debug) 735 (void)printf("cannot get unix auth\n"); 736 #endif 737 return RPC_SYSTEMERROR; 738 } 739 msg.rm_direction = CALL; 740 msg.rm_call.cb_rpcvers = RPC_MSG_VERSION; 741 msg.rm_call.cb_prog = PMAPPROG; 742 msg.rm_call.cb_vers = PMAPVERS; 743 msg.rm_call.cb_proc = PMAPPROC_CALLIT; 744 msg.rm_call.cb_cred = rpcua->ah_cred; 745 msg.rm_call.cb_verf = rpcua->ah_verf; 746 747 msg.rm_xid = ypdb->dom_xid; 748 xdrmem_create(&xdr, buf, (u_int)sizeof(buf), XDR_ENCODE); 749 if (!xdr_callmsg(&xdr, &msg)) { 750 st = RPC_CANTENCODEARGS; 751 AUTH_DESTROY(rpcua); 752 return st; 753 } 754 if (!xdr_rmtcall_args(&xdr, &rmtca)) { 755 st = RPC_CANTENCODEARGS; 756 AUTH_DESTROY(rpcua); 757 return st; 758 } 759 outlen = (int)xdr_getpos(&xdr); 760 xdr_destroy(&xdr); 761 if (outlen < 1) { 762 st = RPC_CANTENCODEARGS; 763 AUTH_DESTROY(rpcua); 764 return st; 765 } 766 AUTH_DESTROY(rpcua); 767 768 if (ypdb->dom_lockfd != -1) { 769 (void)close(ypdb->dom_lockfd); 770 ypdb->dom_lockfd = -1; 771 removelock(ypdb); 772 } 773 774 if (ypdb->dom_alive == 2) { 775 /* 776 * This resolves the following situation: 777 * ypserver on other subnet was once bound, 778 * but rebooted and is now using a different port 779 */ 780 struct sockaddr_in bindsin; 781 782 (void)memset(&bindsin, 0, sizeof bindsin); 783 bindsin.sin_family = AF_INET; 784 bindsin.sin_len = sizeof(bindsin); 785 bindsin.sin_port = htons(PMAPPORT); 786 bindsin.sin_addr = ypdb->dom_server_addr.sin_addr; 787 788 if (sendto(rpcsock, buf, outlen, 0, 789 (struct sockaddr *)(void *)&bindsin, 790 (socklen_t)sizeof bindsin) == -1) 791 yp_log(LOG_WARNING, "nag_servers: sendto: %m"); 792 } 793 794 switch (ypbindmode) { 795 case YPBIND_SETALL: 796 case YPBIND_SETLOCAL: 797 if (been_ypset) 798 return direct_set(buf, outlen, ypdb); 799 /* FALLTHROUGH */ 800 801 case YPBIND_BROADCAST: 802 return broadcast(buf, outlen); 803 804 case YPBIND_DIRECT: 805 return direct(buf, outlen); 806 } 807 /*NOTREACHED*/ 808 return -1; 809 } 810 811 static int 812 broadcast(char *buf, int outlen) 813 { 814 struct ifaddrs *ifap, *ifa; 815 struct sockaddr_in bindsin; 816 struct in_addr in; 817 818 (void)memset(&bindsin, 0, sizeof bindsin); 819 bindsin.sin_family = AF_INET; 820 bindsin.sin_len = sizeof(bindsin); 821 bindsin.sin_port = htons(PMAPPORT); 822 823 if (getifaddrs(&ifap) != 0) { 824 yp_log(LOG_WARNING, "broadcast: getifaddrs: %m"); 825 return (-1); 826 } 827 for (ifa = ifap; ifa; ifa = ifa->ifa_next) { 828 if (ifa->ifa_addr->sa_family != AF_INET) 829 continue; 830 if ((ifa->ifa_flags & IFF_UP) == 0) 831 continue; 832 833 switch (ifa->ifa_flags & (IFF_LOOPBACK | IFF_BROADCAST)) { 834 case IFF_BROADCAST: 835 if (!ifa->ifa_broadaddr) 836 continue; 837 if (ifa->ifa_broadaddr->sa_family != AF_INET) 838 continue; 839 in = ((struct sockaddr_in *)(void *)ifa->ifa_broadaddr)->sin_addr; 840 break; 841 case IFF_LOOPBACK: 842 in = ((struct sockaddr_in *)(void *)ifa->ifa_addr)->sin_addr; 843 break; 844 default: 845 continue; 846 } 847 848 bindsin.sin_addr = in; 849 #ifdef DEBUG 850 if (debug) 851 (void)printf("broadcast %x\n", 852 bindsin.sin_addr.s_addr); 853 #endif 854 if (sendto(rpcsock, buf, outlen, 0, 855 (struct sockaddr *)(void *)&bindsin, 856 (socklen_t)bindsin.sin_len) == -1) 857 yp_log(LOG_WARNING, "broadcast: sendto: %m"); 858 } 859 freeifaddrs(ifap); 860 return (0); 861 } 862 863 static int 864 direct(char *buf, int outlen) 865 { 866 static FILE *df; 867 static char ypservers_path[MAXPATHLEN]; 868 char line[_POSIX2_LINE_MAX]; 869 char *p; 870 struct hostent *hp; 871 struct sockaddr_in bindsin; 872 int i, count = 0; 873 874 if (df) 875 rewind(df); 876 else { 877 (void)snprintf(ypservers_path, sizeof(ypservers_path), 878 "%s/%s%s", BINDINGDIR, domainname, YPSERVERSSUFF); 879 df = fopen(ypservers_path, "r"); 880 if (df == NULL) { 881 yp_log(LOG_ERR, "%s: ", ypservers_path); 882 exit(1); 883 } 884 } 885 886 (void)memset(&bindsin, 0, sizeof bindsin); 887 bindsin.sin_family = AF_INET; 888 bindsin.sin_len = sizeof(bindsin); 889 bindsin.sin_port = htons(PMAPPORT); 890 891 while(fgets(line, (int)sizeof(line), df) != NULL) { 892 /* skip lines that are too big */ 893 p = strchr(line, '\n'); 894 if (p == NULL) { 895 int c; 896 897 while ((c = getc(df)) != '\n' && c != EOF) 898 ; 899 continue; 900 } 901 *p = '\0'; 902 p = line; 903 while (isspace((unsigned char)*p)) 904 p++; 905 if (*p == '#') 906 continue; 907 hp = gethostbyname(p); 908 if (!hp) { 909 yp_log(LOG_WARNING, "%s: %s", p, hstrerror(h_errno)); 910 continue; 911 } 912 /* step through all addresses in case first is unavailable */ 913 for (i = 0; hp->h_addr_list[i]; i++) { 914 (void)memcpy(&bindsin.sin_addr, hp->h_addr_list[0], 915 hp->h_length); 916 if (sendto(rpcsock, buf, outlen, 0, 917 (struct sockaddr *)(void *)&bindsin, 918 (socklen_t)sizeof(bindsin)) < 0) { 919 yp_log(LOG_WARNING, "direct: sendto: %m"); 920 continue; 921 } else 922 count++; 923 } 924 } 925 if (!count) { 926 yp_log(LOG_WARNING, "no contactable servers found in %s", 927 ypservers_path); 928 return -1; 929 } 930 return 0; 931 } 932 933 static int 934 direct_set(char *buf, int outlen, struct _dom_binding *ypdb) 935 { 936 struct sockaddr_in bindsin; 937 char path[MAXPATHLEN]; 938 struct iovec iov[2]; 939 struct ypbind_resp ybr; 940 SVCXPRT dummy_svc; 941 int fd; 942 ssize_t bytes; 943 944 /* 945 * Gack, we lose if binding file went away. We reset 946 * "been_set" if this happens, otherwise we'll never 947 * bind again. 948 */ 949 (void)snprintf(path, sizeof(path), "%s/%s.%ld", BINDINGDIR, 950 ypdb->dom_domain, ypdb->dom_vers); 951 952 if ((fd = open(path, O_SHLOCK|O_RDONLY, 0644)) == -1) { 953 yp_log(LOG_WARNING, "%s: %m", path); 954 been_ypset = 0; 955 return -1; 956 } 957 958 #if O_SHLOCK == 0 959 (void)flock(fd, LOCK_SH); 960 #endif 961 962 /* Read the binding file... */ 963 iov[0].iov_base = &(dummy_svc.xp_port); 964 iov[0].iov_len = sizeof(dummy_svc.xp_port); 965 iov[1].iov_base = &ybr; 966 iov[1].iov_len = sizeof(ybr); 967 bytes = readv(fd, iov, 2); 968 (void)close(fd); 969 if (bytes != (iov[0].iov_len + iov[1].iov_len)) { 970 /* Binding file corrupt? */ 971 yp_log(LOG_WARNING, "%s: %m", path); 972 been_ypset = 0; 973 return -1; 974 } 975 976 bindsin.sin_addr = 977 ybr.ypbind_respbody.ypbind_bindinfo.ypbind_binding_addr; 978 979 if (sendto(rpcsock, buf, outlen, 0, 980 (struct sockaddr *)(void *)&bindsin, 981 (socklen_t)sizeof(bindsin)) < 0) { 982 yp_log(LOG_WARNING, "direct_set: sendto: %m"); 983 return -1; 984 } 985 986 return 0; 987 } 988 989 static enum clnt_stat 990 handle_replies(void) 991 { 992 char buf[BUFSIZE]; 993 socklen_t fromlen; 994 ssize_t inlen; 995 struct _dom_binding *ypdb; 996 struct sockaddr_in raddr; 997 struct rpc_msg msg; 998 XDR xdr; 999 1000 recv_again: 1001 #ifdef DEBUG 1002 if (debug) 1003 printf("handle_replies receiving\n"); 1004 #endif 1005 (void)memset(&xdr, 0, sizeof(xdr)); 1006 (void)memset(&msg, 0, sizeof(msg)); 1007 msg.acpted_rply.ar_verf = _null_auth; 1008 msg.acpted_rply.ar_results.where = (caddr_t)(void *)&rmtcr; 1009 msg.acpted_rply.ar_results.proc = xdr_rmtcallres; 1010 1011 try_again: 1012 fromlen = sizeof(struct sockaddr); 1013 inlen = recvfrom(rpcsock, buf, sizeof buf, 0, 1014 (struct sockaddr *)(void *)&raddr, &fromlen); 1015 if (inlen < 0) { 1016 if (errno == EINTR) 1017 goto try_again; 1018 #ifdef DEBUG 1019 if (debug) 1020 printf("handle_replies: recvfrom failed (%s)\n", 1021 strerror(errno)); 1022 #endif 1023 return RPC_CANTRECV; 1024 } 1025 if (inlen < sizeof(u_int32_t)) 1026 goto recv_again; 1027 1028 /* 1029 * see if reply transaction id matches sent id. 1030 * If so, decode the results. 1031 */ 1032 xdrmem_create(&xdr, buf, (u_int)inlen, XDR_DECODE); 1033 if (xdr_replymsg(&xdr, &msg)) { 1034 if ((msg.rm_reply.rp_stat == MSG_ACCEPTED) && 1035 (msg.acpted_rply.ar_stat == SUCCESS)) { 1036 raddr.sin_port = htons((u_short)rmtcr_port); 1037 ypdb = xid2ypdb(msg.rm_xid); 1038 if (ypdb != NULL) 1039 rpc_received(ypdb->dom_domain, &raddr, 0); 1040 } 1041 } 1042 xdr.x_op = XDR_FREE; 1043 msg.acpted_rply.ar_results.proc = xdr_void; 1044 xdr_destroy(&xdr); 1045 1046 return RPC_SUCCESS; 1047 } 1048 1049 static enum clnt_stat 1050 handle_ping(void) 1051 { 1052 char buf[BUFSIZE]; 1053 socklen_t fromlen; 1054 ssize_t inlen; 1055 struct _dom_binding *ypdb; 1056 struct sockaddr_in raddr; 1057 struct rpc_msg msg; 1058 XDR xdr; 1059 bool_t res; 1060 1061 recv_again: 1062 #ifdef DEBUG 1063 if (debug) 1064 printf("handle_ping receiving\n"); 1065 #endif 1066 (void)memset(&xdr, 0, sizeof(xdr)); 1067 (void)memset(&msg, 0, sizeof(msg)); 1068 msg.acpted_rply.ar_verf = _null_auth; 1069 msg.acpted_rply.ar_results.where = (caddr_t)(void *)&res; 1070 msg.acpted_rply.ar_results.proc = xdr_bool; 1071 1072 try_again: 1073 fromlen = sizeof (struct sockaddr); 1074 inlen = recvfrom(pingsock, buf, sizeof buf, 0, 1075 (struct sockaddr *)(void *)&raddr, &fromlen); 1076 if (inlen < 0) { 1077 if (errno == EINTR) 1078 goto try_again; 1079 #ifdef DEBUG 1080 if (debug) 1081 printf("handle_ping: recvfrom failed (%s)\n", 1082 strerror(errno)); 1083 #endif 1084 return RPC_CANTRECV; 1085 } 1086 if (inlen < sizeof(u_int32_t)) 1087 goto recv_again; 1088 1089 /* 1090 * see if reply transaction id matches sent id. 1091 * If so, decode the results. 1092 */ 1093 xdrmem_create(&xdr, buf, (u_int)inlen, XDR_DECODE); 1094 if (xdr_replymsg(&xdr, &msg)) { 1095 if ((msg.rm_reply.rp_stat == MSG_ACCEPTED) && 1096 (msg.acpted_rply.ar_stat == SUCCESS)) { 1097 ypdb = xid2ypdb(msg.rm_xid); 1098 if (ypdb != NULL) 1099 rpc_received(ypdb->dom_domain, &raddr, 0); 1100 } 1101 } 1102 xdr.x_op = XDR_FREE; 1103 msg.acpted_rply.ar_results.proc = xdr_void; 1104 xdr_destroy(&xdr); 1105 1106 return RPC_SUCCESS; 1107 } 1108 1109 /* 1110 * LOOPBACK IS MORE IMPORTANT: PUT IN HACK 1111 */ 1112 void 1113 rpc_received(char *dom, struct sockaddr_in *raddrp, int force) 1114 { 1115 struct _dom_binding *ypdb; 1116 struct iovec iov[2]; 1117 struct ypbind_resp ybr; 1118 int fd; 1119 1120 #ifdef DEBUG 1121 if (debug) 1122 (void)printf("returned from %s about %s\n", 1123 inet_ntoa(raddrp->sin_addr), dom); 1124 #endif 1125 1126 if (dom == NULL) 1127 return; 1128 1129 if (_yp_invalid_domain(dom)) 1130 return; 1131 1132 /* don't support insecure servers by default */ 1133 if (!insecure && ntohs(raddrp->sin_port) >= IPPORT_RESERVED) 1134 return; 1135 1136 for (ypdb = ypbindlist; ypdb; ypdb = ypdb->dom_pnext) 1137 if (!strcmp(ypdb->dom_domain, dom)) 1138 break; 1139 1140 if (ypdb == NULL) { 1141 if (force == 0) 1142 return; 1143 ypdb = makebinding(dom); 1144 ypdb->dom_lockfd = -1; 1145 ypdb->dom_pnext = ypbindlist; 1146 ypbindlist = ypdb; 1147 } 1148 1149 /* soft update, alive */ 1150 if (ypdb->dom_alive == 1 && force == 0) { 1151 if (!memcmp(&ypdb->dom_server_addr, raddrp, 1152 sizeof ypdb->dom_server_addr)) { 1153 ypdb->dom_alive = 1; 1154 /* recheck binding in 60 sec */ 1155 ypdb->dom_check_t = time(NULL) + 60; 1156 } 1157 return; 1158 } 1159 1160 (void)memcpy(&ypdb->dom_server_addr, raddrp, 1161 sizeof ypdb->dom_server_addr); 1162 /* recheck binding in 60 seconds */ 1163 ypdb->dom_check_t = time(NULL) + 60; 1164 ypdb->dom_vers = YPVERS; 1165 ypdb->dom_alive = 1; 1166 1167 if (ypdb->dom_lockfd != -1) 1168 (void)close(ypdb->dom_lockfd); 1169 1170 if ((fd = makelock(ypdb)) == -1) 1171 return; 1172 1173 /* 1174 * ok, if BINDINGDIR exists, and we can create the binding file, 1175 * then write to it.. 1176 */ 1177 ypdb->dom_lockfd = fd; 1178 1179 iov[0].iov_base = &(udptransp->xp_port); 1180 iov[0].iov_len = sizeof udptransp->xp_port; 1181 iov[1].iov_base = &ybr; 1182 iov[1].iov_len = sizeof ybr; 1183 1184 (void)memset(&ybr, 0, sizeof ybr); 1185 ybr.ypbind_status = YPBIND_SUCC_VAL; 1186 ybr.ypbind_respbody.ypbind_bindinfo.ypbind_binding_addr = 1187 raddrp->sin_addr; 1188 ybr.ypbind_respbody.ypbind_bindinfo.ypbind_binding_port = 1189 raddrp->sin_port; 1190 1191 if (writev(ypdb->dom_lockfd, iov, 2) != 1192 iov[0].iov_len + iov[1].iov_len) { 1193 yp_log(LOG_WARNING, "writev: %m"); 1194 (void)close(ypdb->dom_lockfd); 1195 removelock(ypdb); 1196 ypdb->dom_lockfd = -1; 1197 } 1198 } 1199 1200 static struct _dom_binding * 1201 xid2ypdb(u_int32_t xid) 1202 { 1203 struct _dom_binding *ypdb; 1204 1205 for (ypdb = ypbindlist; ypdb; ypdb = ypdb->dom_pnext) 1206 if (ypdb->dom_xid == xid) 1207 break; 1208 return (ypdb); 1209 } 1210 1211 static u_int32_t 1212 unique_xid(struct _dom_binding *ypdb) 1213 { 1214 u_int32_t tmp_xid; 1215 1216 tmp_xid = ((u_int32_t)(u_long)ypdb) & 0xffffffff; 1217 while (xid2ypdb(tmp_xid) != NULL) 1218 tmp_xid++; 1219 1220 return tmp_xid; 1221 } 1222