1 /* $NetBSD: ypbind.c,v 1.53 2004/10/30 15:57:43 dsl 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 1.53 2004/10/30 15:57:43 dsl 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 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 vfprintf(stderr, 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 ypbindproc_null_2(SVCXPRT *transp, void *argp) 226 { 227 static char res; 228 229 #ifdef DEBUG 230 if (debug) 231 printf("ypbindproc_null_2\n"); 232 #endif 233 (void)memset(&res, 0, sizeof(res)); 234 return (void *)&res; 235 } 236 237 static void * 238 ypbindproc_domain_2(SVCXPRT *transp, void *argp) 239 { 240 static struct ypbind_resp res; 241 struct _dom_binding *ypdb; 242 char *arg = *(char **) argp; 243 time_t now; 244 int count; 245 246 #ifdef DEBUG 247 if (debug) 248 printf("ypbindproc_domain_2 %s\n", arg); 249 #endif 250 if (_yp_invalid_domain(arg)) 251 return NULL; 252 253 (void)memset(&res, 0, sizeof res); 254 res.ypbind_status = YPBIND_FAIL_VAL; 255 256 for (count = 0, ypdb = ypbindlist; 257 ypdb != NULL; 258 ypdb = ypdb->dom_pnext, count++) { 259 if (count > 100) 260 return NULL; /* prevent denial of service */ 261 if (!strcmp(ypdb->dom_domain, arg)) 262 break; 263 } 264 265 if (ypdb == NULL) { 266 ypdb = makebinding(arg); 267 ypdb->dom_vers = YPVERS; 268 ypdb->dom_alive = 0; 269 ypdb->dom_lockfd = -1; 270 removelock(ypdb); 271 ypdb->dom_xid = unique_xid(ypdb); 272 ypdb->dom_pnext = ypbindlist; 273 ypbindlist = ypdb; 274 check++; 275 #ifdef DEBUG 276 if (debug) 277 printf("unknown domain %s\n", arg); 278 #endif 279 return NULL; 280 } 281 282 if (ypdb->dom_alive == 0) { 283 #ifdef DEBUG 284 if (debug) 285 printf("dead domain %s\n", arg); 286 #endif 287 return NULL; 288 } 289 290 #ifdef HEURISTIC 291 time(&now); 292 if (now < ypdb->dom_ask_t + 5) { 293 /* 294 * Hmm. More than 2 requests in 5 seconds have indicated 295 * that my binding is possibly incorrect. 296 * Ok, do an immediate poll of the server. 297 */ 298 if (ypdb->dom_check_t >= now) { 299 /* don't flood it */ 300 ypdb->dom_check_t = 0; 301 check++; 302 } 303 } 304 ypdb->dom_ask_t = now; 305 #endif 306 307 res.ypbind_status = YPBIND_SUCC_VAL; 308 res.ypbind_respbody.ypbind_bindinfo.ypbind_binding_addr.s_addr = 309 ypdb->dom_server_addr.sin_addr.s_addr; 310 res.ypbind_respbody.ypbind_bindinfo.ypbind_binding_port = 311 ypdb->dom_server_addr.sin_port; 312 #ifdef DEBUG 313 if (debug) 314 printf("domain %s at %s/%d\n", ypdb->dom_domain, 315 inet_ntoa(ypdb->dom_server_addr.sin_addr), 316 ntohs(ypdb->dom_server_addr.sin_port)); 317 #endif 318 return &res; 319 } 320 321 static void * 322 ypbindproc_setdom_2(SVCXPRT *transp, void *argp) 323 { 324 struct ypbind_setdom *sd = argp; 325 struct sockaddr_in *fromsin, bindsin; 326 static bool_t res; 327 328 #ifdef DEBUG 329 if (debug) 330 printf("ypbindproc_setdom_2 %s\n", inet_ntoa(bindsin.sin_addr)); 331 #endif 332 (void)memset(&res, 0, sizeof(res)); 333 fromsin = svc_getcaller(transp); 334 335 switch (ypbindmode) { 336 case YPBIND_SETLOCAL: 337 if (fromsin->sin_addr.s_addr != htonl(INADDR_LOOPBACK)) { 338 #ifdef DEBUG 339 if (debug) 340 printf("ypset from %s denied\n", 341 inet_ntoa(fromsin->sin_addr)); 342 #endif 343 return NULL; 344 } 345 /* FALLTHROUGH */ 346 347 case YPBIND_SETALL: 348 been_ypset = 1; 349 break; 350 351 case YPBIND_DIRECT: 352 case YPBIND_BROADCAST: 353 default: 354 #ifdef DEBUG 355 if (debug) 356 printf("ypset denied\n"); 357 #endif 358 return NULL; 359 } 360 361 if (ntohs(fromsin->sin_port) >= IPPORT_RESERVED) { 362 #ifdef DEBUG 363 if (debug) 364 printf("ypset from unprivileged port denied\n"); 365 #endif 366 return &res; 367 } 368 369 if (sd->ypsetdom_vers != YPVERS) { 370 #ifdef DEBUG 371 if (debug) 372 printf("ypset with wrong version denied\n"); 373 #endif 374 return &res; 375 } 376 377 (void)memset(&bindsin, 0, sizeof bindsin); 378 bindsin.sin_family = AF_INET; 379 bindsin.sin_len = sizeof(bindsin); 380 bindsin.sin_addr = sd->ypsetdom_addr; 381 bindsin.sin_port = sd->ypsetdom_port; 382 rpc_received(sd->ypsetdom_domain, &bindsin, 1); 383 384 #ifdef DEBUG 385 if (debug) 386 printf("ypset to %s succeeded\n", inet_ntoa(bindsin.sin_addr)); 387 #endif 388 res = 1; 389 return &res; 390 } 391 392 static void 393 ypbindprog_2(struct svc_req *rqstp, register SVCXPRT *transp) 394 { 395 union { 396 char ypbindproc_domain_2_arg[YPMAXDOMAIN + 1]; 397 struct ypbind_setdom ypbindproc_setdom_2_arg; 398 } argument; 399 struct authunix_parms *creds; 400 char *result; 401 xdrproc_t xdr_argument, xdr_result; 402 void *(*local)(SVCXPRT *, void *); 403 404 switch (rqstp->rq_proc) { 405 case YPBINDPROC_NULL: 406 xdr_argument = xdr_void; 407 xdr_result = xdr_void; 408 local = ypbindproc_null_2; 409 break; 410 411 case YPBINDPROC_DOMAIN: 412 xdr_argument = xdr_ypdomain_wrap_string; 413 xdr_result = xdr_ypbind_resp; 414 local = ypbindproc_domain_2; 415 break; 416 417 case YPBINDPROC_SETDOM: 418 switch (rqstp->rq_cred.oa_flavor) { 419 case AUTH_UNIX: 420 creds = (struct authunix_parms *)rqstp->rq_clntcred; 421 if (creds->aup_uid != 0) { 422 svcerr_auth(transp, AUTH_BADCRED); 423 return; 424 } 425 break; 426 default: 427 svcerr_auth(transp, AUTH_TOOWEAK); 428 return; 429 } 430 431 xdr_argument = xdr_ypbind_setdom; 432 xdr_result = xdr_void; 433 local = ypbindproc_setdom_2; 434 break; 435 436 default: 437 svcerr_noproc(transp); 438 return; 439 } 440 (void)memset(&argument, 0, sizeof(argument)); 441 if (!svc_getargs(transp, xdr_argument, (caddr_t)&argument)) { 442 svcerr_decode(transp); 443 return; 444 } 445 result = (*local)(transp, &argument); 446 if (result != NULL && !svc_sendreply(transp, xdr_result, result)) { 447 svcerr_systemerr(transp); 448 } 449 return; 450 } 451 452 int 453 main(int argc, char *argv[]) 454 { 455 struct timeval tv; 456 fd_set fdsr; 457 int width, lockfd; 458 int evil = 0, one; 459 char pathname[MAXPATHLEN]; 460 struct stat st; 461 462 yp_get_default_domain(&domainname); 463 if (domainname[0] == '\0') 464 errx(1, "Domainname not set. Aborting."); 465 466 /* 467 * Per traditional ypbind(8) semantics, if a ypservers 468 * file does not exist, we default to broadcast mode. 469 * If the file does exist, we default to direct mode. 470 * Note that we can still override direct mode by passing 471 * the -broadcast flag. 472 */ 473 snprintf(pathname, sizeof(pathname), "%s/%s%s", BINDINGDIR, 474 domainname, YPSERVERSSUFF); 475 if (stat(pathname, &st) < 0) { 476 #ifdef DEBUG 477 if (debug) 478 fprintf(stderr, 479 "%s does not exist, defaulting to broadcast\n", 480 pathname); 481 #endif 482 ypbindmode = YPBIND_BROADCAST; 483 } else 484 ypbindmode = YPBIND_DIRECT; 485 486 while (--argc) { 487 ++argv; 488 if (!strcmp("-insecure", *argv)) 489 insecure = 1; 490 else if (!strcmp("-ypset", *argv)) 491 ypbindmode = YPBIND_SETALL; 492 else if (!strcmp("-ypsetme", *argv)) 493 ypbindmode = YPBIND_SETLOCAL; 494 else if (!strcmp("-broadcast", *argv)) 495 ypbindmode = YPBIND_BROADCAST; 496 #ifdef DEBUG 497 else if (!strcmp("-d", *argv)) 498 debug++; 499 #endif 500 else 501 usage(); 502 } 503 504 /* initialise syslog */ 505 openlog("ypbind", LOG_PERROR | LOG_PID, LOG_DAEMON); 506 507 /* blow away everything in BINDINGDIR */ 508 509 lockfd = open(_PATH_YPBIND_LOCK, O_CREAT|O_SHLOCK|O_RDWR|O_TRUNC, 0644); 510 if (lockfd == -1) 511 err(1, "Cannot create %s", _PATH_YPBIND_LOCK); 512 513 #if O_SHLOCK == 0 514 (void)flock(lockfd, LOCK_SH); 515 #endif 516 517 (void)pmap_unset(YPBINDPROG, YPBINDVERS); 518 519 udptransp = svcudp_create(RPC_ANYSOCK); 520 if (udptransp == NULL) 521 errx(1, "Cannot create udp service."); 522 523 if (!svc_register(udptransp, YPBINDPROG, YPBINDVERS, ypbindprog_2, 524 IPPROTO_UDP)) 525 errx(1, "Unable to register (YPBINDPROG, YPBINDVERS, udp)."); 526 527 tcptransp = svctcp_create(RPC_ANYSOCK, 0, 0); 528 if (tcptransp == NULL) 529 errx(1, "Cannot create tcp service."); 530 531 if (!svc_register(tcptransp, YPBINDPROG, YPBINDVERS, ypbindprog_2, 532 IPPROTO_TCP)) 533 errx(1, "Unable to register (YPBINDPROG, YPBINDVERS, tcp)."); 534 535 /* XXX use SOCK_STREAM for direct queries? */ 536 if ((rpcsock = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP)) == -1) 537 err(1, "rpc socket"); 538 if ((pingsock = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP)) == -1) 539 err(1, "ping socket"); 540 541 (void)fcntl(rpcsock, F_SETFL, fcntl(rpcsock, F_GETFL, 0) | FNDELAY); 542 (void)fcntl(pingsock, F_SETFL, fcntl(pingsock, F_GETFL, 0) | FNDELAY); 543 544 one = 1; 545 (void)setsockopt(rpcsock, SOL_SOCKET, SO_BROADCAST, &one, sizeof(one)); 546 rmtca.prog = YPPROG; 547 rmtca.vers = YPVERS; 548 rmtca.proc = YPPROC_DOMAIN_NONACK; 549 rmtca.xdr_args = NULL; /* set at call time */ 550 rmtca.args_ptr = NULL; /* set at call time */ 551 rmtcr.port_ptr = &rmtcr_port; 552 rmtcr.xdr_results = xdr_bool; 553 rmtcr.results_ptr = (caddr_t)&rmtcr_outval; 554 555 if (_yp_invalid_domain(domainname)) 556 errx(1, "bad domainname: %s", domainname); 557 558 /* build initial domain binding, make it "unsuccessful" */ 559 ypbindlist = makebinding(domainname); 560 ypbindlist->dom_vers = YPVERS; 561 ypbindlist->dom_alive = 0; 562 ypbindlist->dom_lockfd = -1; 563 removelock(ypbindlist); 564 565 checkwork(); 566 567 for (;;) { 568 width = svc_maxfd; 569 if (rpcsock > width) 570 width = rpcsock; 571 if (pingsock > width) 572 width = pingsock; 573 width++; 574 fdsr = svc_fdset; 575 FD_SET(rpcsock, &fdsr); 576 FD_SET(pingsock, &fdsr); 577 tv.tv_sec = 1; 578 tv.tv_usec = 0; 579 580 switch (select(width, &fdsr, NULL, NULL, &tv)) { 581 case 0: 582 checkwork(); 583 break; 584 case -1: 585 yp_log(LOG_WARNING, "select: %m"); 586 break; 587 default: 588 if (FD_ISSET(rpcsock, &fdsr)) 589 handle_replies(); 590 if (FD_ISSET(pingsock, &fdsr)) 591 handle_ping(); 592 svc_getreqset(&fdsr); 593 if (check) 594 checkwork(); 595 break; 596 } 597 598 if (!evil && ypbindlist->dom_alive) { 599 evil = 1; 600 #ifdef DEBUG 601 if (!debug) 602 #endif 603 daemon(0, 0); 604 pidfile(NULL); 605 } 606 } 607 } 608 609 /* 610 * State transition is done like this: 611 * 612 * STATE EVENT ACTION NEWSTATE TIMEOUT 613 * no binding timeout broadcast no binding 5 sec 614 * no binding answer -- binding 60 sec 615 * binding timeout ping server checking 5 sec 616 * checking timeout ping server + broadcast checking 5 sec 617 * checking answer -- binding 60 sec 618 */ 619 void 620 checkwork(void) 621 { 622 struct _dom_binding *ypdb; 623 time_t t; 624 625 check = 0; 626 627 time(&t); 628 for (ypdb = ypbindlist; ypdb; ypdb = ypdb->dom_pnext) { 629 if (ypdb->dom_check_t < t) { 630 if (ypdb->dom_alive == 1) 631 ping(ypdb); 632 else 633 nag_servers(ypdb); 634 time(&t); 635 ypdb->dom_check_t = t + 5; 636 } 637 } 638 } 639 640 int 641 ping(struct _dom_binding *ypdb) 642 { 643 char *dom = ypdb->dom_domain; 644 struct rpc_msg msg; 645 char buf[BUFSIZE]; 646 enum clnt_stat st; 647 int outlen; 648 AUTH *rpcua; 649 XDR xdr; 650 651 (void)memset(&xdr, 0, sizeof xdr); 652 (void)memset(&msg, 0, sizeof msg); 653 654 rpcua = authunix_create_default(); 655 if (rpcua == NULL) { 656 #ifdef DEBUG 657 if (debug) 658 printf("cannot get unix auth\n"); 659 #endif 660 return RPC_SYSTEMERROR; 661 } 662 663 msg.rm_direction = CALL; 664 msg.rm_call.cb_rpcvers = RPC_MSG_VERSION; 665 msg.rm_call.cb_prog = YPPROG; 666 msg.rm_call.cb_vers = YPVERS; 667 msg.rm_call.cb_proc = YPPROC_DOMAIN_NONACK; 668 msg.rm_call.cb_cred = rpcua->ah_cred; 669 msg.rm_call.cb_verf = rpcua->ah_verf; 670 671 msg.rm_xid = ypdb->dom_xid; 672 xdrmem_create(&xdr, buf, sizeof buf, XDR_ENCODE); 673 if (!xdr_callmsg(&xdr, &msg)) { 674 st = RPC_CANTENCODEARGS; 675 AUTH_DESTROY(rpcua); 676 return st; 677 } 678 if (!xdr_ypdomain_wrap_string(&xdr, &dom)) { 679 st = RPC_CANTENCODEARGS; 680 AUTH_DESTROY(rpcua); 681 return st; 682 } 683 outlen = (int)xdr_getpos(&xdr); 684 xdr_destroy(&xdr); 685 if (outlen < 1) { 686 st = RPC_CANTENCODEARGS; 687 AUTH_DESTROY(rpcua); 688 return st; 689 } 690 AUTH_DESTROY(rpcua); 691 692 ypdb->dom_alive = 2; 693 if (sendto(pingsock, buf, outlen, 0, 694 (struct sockaddr *)&ypdb->dom_server_addr, 695 sizeof ypdb->dom_server_addr) == -1) 696 yp_log(LOG_WARNING, "ping: sendto: %m"); 697 return 0; 698 699 } 700 701 static int 702 nag_servers(struct _dom_binding *ypdb) 703 { 704 char *dom = ypdb->dom_domain; 705 struct rpc_msg msg; 706 char buf[BUFSIZE]; 707 enum clnt_stat st; 708 int outlen; 709 AUTH *rpcua; 710 XDR xdr; 711 712 rmtca.xdr_args = xdr_ypdomain_wrap_string; 713 rmtca.args_ptr = (char *)&dom; 714 715 (void)memset(&xdr, 0, sizeof xdr); 716 (void)memset(&msg, 0, sizeof msg); 717 718 rpcua = authunix_create_default(); 719 if (rpcua == NULL) { 720 #ifdef DEBUG 721 if (debug) 722 printf("cannot get unix auth\n"); 723 #endif 724 return RPC_SYSTEMERROR; 725 } 726 msg.rm_direction = CALL; 727 msg.rm_call.cb_rpcvers = RPC_MSG_VERSION; 728 msg.rm_call.cb_prog = PMAPPROG; 729 msg.rm_call.cb_vers = PMAPVERS; 730 msg.rm_call.cb_proc = PMAPPROC_CALLIT; 731 msg.rm_call.cb_cred = rpcua->ah_cred; 732 msg.rm_call.cb_verf = rpcua->ah_verf; 733 734 msg.rm_xid = ypdb->dom_xid; 735 xdrmem_create(&xdr, buf, sizeof buf, XDR_ENCODE); 736 if (!xdr_callmsg(&xdr, &msg)) { 737 st = RPC_CANTENCODEARGS; 738 AUTH_DESTROY(rpcua); 739 return st; 740 } 741 if (!xdr_rmtcall_args(&xdr, &rmtca)) { 742 st = RPC_CANTENCODEARGS; 743 AUTH_DESTROY(rpcua); 744 return st; 745 } 746 outlen = (int)xdr_getpos(&xdr); 747 xdr_destroy(&xdr); 748 if (outlen < 1) { 749 st = RPC_CANTENCODEARGS; 750 AUTH_DESTROY(rpcua); 751 return st; 752 } 753 AUTH_DESTROY(rpcua); 754 755 if (ypdb->dom_lockfd != -1) { 756 (void)close(ypdb->dom_lockfd); 757 ypdb->dom_lockfd = -1; 758 removelock(ypdb); 759 } 760 761 if (ypdb->dom_alive == 2) { 762 /* 763 * This resolves the following situation: 764 * ypserver on other subnet was once bound, 765 * but rebooted and is now using a different port 766 */ 767 struct sockaddr_in bindsin; 768 769 memset(&bindsin, 0, sizeof bindsin); 770 bindsin.sin_family = AF_INET; 771 bindsin.sin_len = sizeof(bindsin); 772 bindsin.sin_port = htons(PMAPPORT); 773 bindsin.sin_addr = ypdb->dom_server_addr.sin_addr; 774 775 if (sendto(rpcsock, buf, outlen, 0, (struct sockaddr *)&bindsin, 776 sizeof bindsin) == -1) 777 yp_log(LOG_WARNING, "broadcast: sendto: %m"); 778 } 779 780 switch (ypbindmode) { 781 case YPBIND_SETALL: 782 case YPBIND_SETLOCAL: 783 if (been_ypset) 784 return direct_set(buf, outlen, ypdb); 785 /* FALLTHROUGH */ 786 787 case YPBIND_BROADCAST: 788 return broadcast(buf, outlen); 789 790 case YPBIND_DIRECT: 791 return direct(buf, outlen); 792 } 793 794 return -1; 795 } 796 797 static int 798 broadcast(char *buf, int outlen) 799 { 800 struct ifaddrs *ifap, *ifa; 801 struct sockaddr_in bindsin; 802 struct in_addr in; 803 804 memset(&bindsin, 0, sizeof bindsin); 805 bindsin.sin_family = AF_INET; 806 bindsin.sin_len = sizeof(bindsin); 807 bindsin.sin_port = htons(PMAPPORT); 808 809 if (getifaddrs(&ifap) != 0) { 810 yp_log(LOG_WARNING, "broadcast: getifaddrs: %m"); 811 return (-1); 812 } 813 for (ifa = ifap; ifa; ifa = ifa->ifa_next) { 814 if (ifa->ifa_addr->sa_family != AF_INET) 815 continue; 816 if ((ifa->ifa_flags & IFF_UP) == 0) 817 continue; 818 819 switch (ifa->ifa_flags & (IFF_LOOPBACK | IFF_BROADCAST)) { 820 case IFF_BROADCAST: 821 if (!ifa->ifa_broadaddr) 822 continue; 823 if (ifa->ifa_broadaddr->sa_family != AF_INET) 824 continue; 825 in = ((struct sockaddr_in *)ifa->ifa_broadaddr)->sin_addr; 826 break; 827 case IFF_LOOPBACK: 828 in = ((struct sockaddr_in *)ifa->ifa_addr)->sin_addr; 829 break; 830 default: 831 continue; 832 } 833 834 bindsin.sin_addr = in; 835 if (sendto(rpcsock, buf, outlen, 0, (struct sockaddr *)&bindsin, 836 bindsin.sin_len) == -1) 837 yp_log(LOG_WARNING, "broadcast: sendto: %m"); 838 } 839 freeifaddrs(ifap); 840 return (0); 841 } 842 843 static int 844 direct(char *buf, int outlen) 845 { 846 static FILE *df; 847 static char ypservers_path[MAXPATHLEN]; 848 char line[_POSIX2_LINE_MAX]; 849 char *p; 850 struct hostent *hp; 851 struct sockaddr_in bindsin; 852 int i, count = 0; 853 854 if (df) 855 rewind(df); 856 else { 857 snprintf(ypservers_path, sizeof(ypservers_path), 858 "%s/%s%s", BINDINGDIR, domainname, YPSERVERSSUFF); 859 df = fopen(ypservers_path, "r"); 860 if (df == NULL) { 861 yp_log(LOG_ERR, "%s: ", ypservers_path); 862 exit(1); 863 } 864 } 865 866 memset(&bindsin, 0, sizeof bindsin); 867 bindsin.sin_family = AF_INET; 868 bindsin.sin_len = sizeof(bindsin); 869 bindsin.sin_port = htons(PMAPPORT); 870 871 while(fgets(line, sizeof(line), df) != NULL) { 872 /* skip lines that are too big */ 873 p = strchr(line, '\n'); 874 if (p == NULL) { 875 int c; 876 877 while ((c = getc(df)) != '\n' && c != EOF) 878 ; 879 continue; 880 } 881 *p = '\0'; 882 p = line; 883 while (isspace((unsigned char)*p)) 884 p++; 885 if (*p == '#') 886 continue; 887 hp = gethostbyname(p); 888 if (!hp) { 889 yp_log(LOG_WARNING, "%s: %s", p, hstrerror(h_errno)); 890 continue; 891 } 892 /* step through all addresses in case first is unavailable */ 893 for (i = 0; hp->h_addr_list[i]; i++) { 894 memmove(&bindsin.sin_addr, hp->h_addr_list[0], 895 hp->h_length); 896 if (sendto(rpcsock, buf, outlen, 0, 897 (struct sockaddr *)&bindsin, sizeof bindsin) < 0) { 898 yp_log(LOG_WARNING, "direct: sendto: %m"); 899 continue; 900 } else 901 count++; 902 } 903 } 904 if (!count) { 905 yp_log(LOG_WARNING, "no contactable servers found in %s", 906 ypservers_path); 907 return -1; 908 } 909 return 0; 910 } 911 912 static int 913 direct_set(char *buf, int outlen, struct _dom_binding *ypdb) 914 { 915 struct sockaddr_in bindsin; 916 char path[MAXPATHLEN]; 917 struct iovec iov[2]; 918 struct ypbind_resp ybr; 919 SVCXPRT dummy_svc; 920 int fd, bytes; 921 922 /* 923 * Gack, we lose if binding file went away. We reset 924 * "been_set" if this happens, otherwise we'll never 925 * bind again. 926 */ 927 snprintf(path, sizeof(path), "%s/%s.%ld", BINDINGDIR, 928 ypdb->dom_domain, ypdb->dom_vers); 929 930 if ((fd = open(path, O_SHLOCK|O_RDONLY, 0644)) == -1) { 931 yp_log(LOG_WARNING, "%s: %m", path); 932 been_ypset = 0; 933 return -1; 934 } 935 936 #if O_SHLOCK == 0 937 (void)flock(fd, LOCK_SH); 938 #endif 939 940 /* Read the binding file... */ 941 iov[0].iov_base = (caddr_t)&(dummy_svc.xp_port); 942 iov[0].iov_len = sizeof(dummy_svc.xp_port); 943 iov[1].iov_base = (caddr_t)&ybr; 944 iov[1].iov_len = sizeof(ybr); 945 bytes = readv(fd, iov, 2); 946 (void)close(fd); 947 if (bytes != (iov[0].iov_len + iov[1].iov_len)) { 948 /* Binding file corrupt? */ 949 yp_log(LOG_WARNING, "%s: %m", path); 950 been_ypset = 0; 951 return -1; 952 } 953 954 bindsin.sin_addr = 955 ybr.ypbind_respbody.ypbind_bindinfo.ypbind_binding_addr; 956 957 if (sendto(rpcsock, buf, outlen, 0, (struct sockaddr *)&bindsin, 958 sizeof(bindsin)) < 0) { 959 yp_log(LOG_WARNING, "direct_set: sendto: %m"); 960 return -1; 961 } 962 963 return 0; 964 } 965 966 static enum clnt_stat 967 handle_replies(void) 968 { 969 char buf[BUFSIZE]; 970 int fromlen, inlen; 971 struct _dom_binding *ypdb; 972 struct sockaddr_in raddr; 973 struct rpc_msg msg; 974 XDR xdr; 975 976 recv_again: 977 (void)memset(&xdr, 0, sizeof(xdr)); 978 (void)memset(&msg, 0, sizeof(msg)); 979 msg.acpted_rply.ar_verf = _null_auth; 980 msg.acpted_rply.ar_results.where = (caddr_t)&rmtcr; 981 msg.acpted_rply.ar_results.proc = xdr_rmtcallres; 982 983 try_again: 984 fromlen = sizeof(struct sockaddr); 985 inlen = recvfrom(rpcsock, buf, sizeof buf, 0, 986 (struct sockaddr *)&raddr, &fromlen); 987 if (inlen < 0) { 988 if (errno == EINTR) 989 goto try_again; 990 return RPC_CANTRECV; 991 } 992 if (inlen < sizeof(u_int32_t)) 993 goto recv_again; 994 995 /* 996 * see if reply transaction id matches sent id. 997 * If so, decode the results. 998 */ 999 xdrmem_create(&xdr, buf, (u_int)inlen, XDR_DECODE); 1000 if (xdr_replymsg(&xdr, &msg)) { 1001 if ((msg.rm_reply.rp_stat == MSG_ACCEPTED) && 1002 (msg.acpted_rply.ar_stat == SUCCESS)) { 1003 raddr.sin_port = htons((u_short)rmtcr_port); 1004 ypdb = xid2ypdb(msg.rm_xid); 1005 if (ypdb != NULL) 1006 rpc_received(ypdb->dom_domain, &raddr, 0); 1007 } 1008 } 1009 xdr.x_op = XDR_FREE; 1010 msg.acpted_rply.ar_results.proc = xdr_void; 1011 xdr_destroy(&xdr); 1012 1013 return RPC_SUCCESS; 1014 } 1015 1016 static enum clnt_stat 1017 handle_ping(void) 1018 { 1019 char buf[BUFSIZE]; 1020 int fromlen, inlen; 1021 struct _dom_binding *ypdb; 1022 struct sockaddr_in raddr; 1023 struct rpc_msg msg; 1024 XDR xdr; 1025 bool_t res; 1026 1027 recv_again: 1028 (void)memset(&xdr, 0, sizeof(xdr)); 1029 (void)memset(&msg, 0, sizeof(msg)); 1030 msg.acpted_rply.ar_verf = _null_auth; 1031 msg.acpted_rply.ar_results.where = (caddr_t)&res; 1032 msg.acpted_rply.ar_results.proc = xdr_bool; 1033 1034 try_again: 1035 fromlen = sizeof (struct sockaddr); 1036 inlen = recvfrom(pingsock, buf, sizeof buf, 0, 1037 (struct sockaddr *)&raddr, &fromlen); 1038 if (inlen < 0) { 1039 if (errno == EINTR) 1040 goto try_again; 1041 return RPC_CANTRECV; 1042 } 1043 if (inlen < sizeof(u_int32_t)) 1044 goto recv_again; 1045 1046 /* 1047 * see if reply transaction id matches sent id. 1048 * If so, decode the results. 1049 */ 1050 xdrmem_create(&xdr, buf, (u_int)inlen, XDR_DECODE); 1051 if (xdr_replymsg(&xdr, &msg)) { 1052 if ((msg.rm_reply.rp_stat == MSG_ACCEPTED) && 1053 (msg.acpted_rply.ar_stat == SUCCESS)) { 1054 ypdb = xid2ypdb(msg.rm_xid); 1055 if (ypdb != NULL) 1056 rpc_received(ypdb->dom_domain, &raddr, 0); 1057 } 1058 } 1059 xdr.x_op = XDR_FREE; 1060 msg.acpted_rply.ar_results.proc = xdr_void; 1061 xdr_destroy(&xdr); 1062 1063 return RPC_SUCCESS; 1064 } 1065 1066 /* 1067 * LOOPBACK IS MORE IMPORTANT: PUT IN HACK 1068 */ 1069 void 1070 rpc_received(char *dom, struct sockaddr_in *raddrp, int force) 1071 { 1072 struct _dom_binding *ypdb; 1073 struct iovec iov[2]; 1074 struct ypbind_resp ybr; 1075 int fd; 1076 1077 #ifdef DEBUG 1078 if (debug) 1079 printf("returned from %s about %s\n", 1080 inet_ntoa(raddrp->sin_addr), dom); 1081 #endif 1082 1083 if (dom == NULL) 1084 return; 1085 1086 if (_yp_invalid_domain(dom)) 1087 return; 1088 1089 /* don't support insecure servers by default */ 1090 if (!insecure && ntohs(raddrp->sin_port) >= IPPORT_RESERVED) 1091 return; 1092 1093 for (ypdb = ypbindlist; ypdb; ypdb = ypdb->dom_pnext) 1094 if (!strcmp(ypdb->dom_domain, dom)) 1095 break; 1096 1097 if (ypdb == NULL) { 1098 if (force == 0) 1099 return; 1100 ypdb = makebinding(dom); 1101 ypdb->dom_lockfd = -1; 1102 ypdb->dom_pnext = ypbindlist; 1103 ypbindlist = ypdb; 1104 } 1105 1106 /* soft update, alive */ 1107 if (ypdb->dom_alive == 1 && force == 0) { 1108 if (!memcmp(&ypdb->dom_server_addr, raddrp, 1109 sizeof ypdb->dom_server_addr)) { 1110 ypdb->dom_alive = 1; 1111 /* recheck binding in 60 sec */ 1112 ypdb->dom_check_t = time(NULL) + 60; 1113 } 1114 return; 1115 } 1116 1117 (void)memcpy(&ypdb->dom_server_addr, raddrp, 1118 sizeof ypdb->dom_server_addr); 1119 /* recheck binding in 60 seconds */ 1120 ypdb->dom_check_t = time(NULL) + 60; 1121 ypdb->dom_vers = YPVERS; 1122 ypdb->dom_alive = 1; 1123 1124 if (ypdb->dom_lockfd != -1) 1125 (void)close(ypdb->dom_lockfd); 1126 1127 if ((fd = makelock(ypdb)) == -1) 1128 return; 1129 1130 /* 1131 * ok, if BINDINGDIR exists, and we can create the binding file, 1132 * then write to it.. 1133 */ 1134 ypdb->dom_lockfd = fd; 1135 1136 iov[0].iov_base = (caddr_t)&(udptransp->xp_port); 1137 iov[0].iov_len = sizeof udptransp->xp_port; 1138 iov[1].iov_base = (caddr_t)&ybr; 1139 iov[1].iov_len = sizeof ybr; 1140 1141 (void)memset(&ybr, 0, sizeof ybr); 1142 ybr.ypbind_status = YPBIND_SUCC_VAL; 1143 ybr.ypbind_respbody.ypbind_bindinfo.ypbind_binding_addr = 1144 raddrp->sin_addr; 1145 ybr.ypbind_respbody.ypbind_bindinfo.ypbind_binding_port = 1146 raddrp->sin_port; 1147 1148 if (writev(ypdb->dom_lockfd, iov, 2) != 1149 iov[0].iov_len + iov[1].iov_len) { 1150 yp_log(LOG_WARNING, "writev: %m"); 1151 (void)close(ypdb->dom_lockfd); 1152 removelock(ypdb); 1153 ypdb->dom_lockfd = -1; 1154 } 1155 } 1156 1157 static struct _dom_binding * 1158 xid2ypdb(u_int32_t xid) 1159 { 1160 struct _dom_binding *ypdb; 1161 1162 for (ypdb = ypbindlist; ypdb; ypdb = ypdb->dom_pnext) 1163 if (ypdb->dom_xid == xid) 1164 break; 1165 return (ypdb); 1166 } 1167 1168 static u_int32_t 1169 unique_xid(struct _dom_binding *ypdb) 1170 { 1171 u_int32_t tmp_xid; 1172 1173 tmp_xid = (u_int32_t)(((u_long)ypdb) & 0xffffffff); 1174 while (xid2ypdb(tmp_xid) != NULL) 1175 tmp_xid++; 1176 1177 return tmp_xid; 1178 } 1179