ypbind.c revision 1.50
1/* $NetBSD: ypbind.c,v 1.50 2003/12/10 12:06:26 agc 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 1.50 2003/12/10 12:06:26 agc 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 79struct _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 93static char *domainname; 94 95static struct _dom_binding *ypbindlist; 96static int check; 97 98typedef enum { 99 YPBIND_DIRECT, YPBIND_BROADCAST, YPBIND_SETLOCAL, YPBIND_SETALL 100} ypbind_mode_t; 101 102ypbind_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 */ 109int been_ypset; 110 111#ifdef DEBUG 112static int debug; 113#endif 114 115static int insecure; 116static int rpcsock, pingsock; 117static struct rmtcallargs rmtca; 118static struct rmtcallres rmtcr; 119static bool_t rmtcr_outval; 120static u_long rmtcr_port; 121static SVCXPRT *udptransp, *tcptransp; 122 123int _yp_invalid_domain(const char *); /* from libc */ 124int main(int, char *[]); 125 126static void usage(void); 127static void yp_log(int, const char *, ...) 128 __attribute__((__format__(__printf__, 2, 3))); 129static struct _dom_binding *makebinding(const char *); 130static int makelock(struct _dom_binding *); 131static void removelock(struct _dom_binding *); 132static void *ypbindproc_null_2(SVCXPRT *, void *); 133static void *ypbindproc_domain_2(SVCXPRT *, void *); 134static void *ypbindproc_setdom_2(SVCXPRT *, void *); 135static void ypbindprog_2(struct svc_req *, SVCXPRT *); 136static void checkwork(void); 137static int ping(struct _dom_binding *); 138static int nag_servers(struct _dom_binding *); 139static enum clnt_stat handle_replies(void); 140static enum clnt_stat handle_ping(void); 141static void rpc_received(char *, struct sockaddr_in *, int); 142static struct _dom_binding *xid2ypdb(u_int32_t); 143static u_int32_t unique_xid(struct _dom_binding *); 144static int broadcast(char *, int); 145static int direct(char *, int); 146static int direct_set(char *, int, struct _dom_binding *); 147 148static void 149usage(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 162static void 163yp_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 178static struct _dom_binding * 179makebinding(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)strncpy(ypdb->dom_domain, dm, sizeof ypdb->dom_domain); 190 ypdb->dom_domain[sizeof(ypdb->dom_domain) - 1] = '\0'; 191 return ypdb; 192} 193 194static int 195makelock(struct _dom_binding *ypdb) 196{ 197 int fd; 198 char path[MAXPATHLEN]; 199 200 (void)snprintf(path, sizeof(path), "%s/%s.%ld", BINDINGDIR, 201 ypdb->dom_domain, ypdb->dom_vers); 202 203 if ((fd = open(path, O_CREAT|O_SHLOCK|O_RDWR|O_TRUNC, 0644)) == -1) { 204 (void)mkdir(BINDINGDIR, 0755); 205 if ((fd = open(path, O_CREAT|O_SHLOCK|O_RDWR|O_TRUNC, 0644)) == -1) 206 return -1; 207 } 208 209#if O_SHLOCK == 0 210 (void)flock(fd, LOCK_SH); 211#endif 212 return fd; 213} 214 215static void 216removelock(struct _dom_binding *ypdb) 217{ 218 char path[MAXPATHLEN]; 219 220 (void)snprintf(path, sizeof(path), "%s/%s.%ld", 221 BINDINGDIR, ypdb->dom_domain, ypdb->dom_vers); 222 (void)unlink(path); 223} 224 225static void * 226ypbindproc_null_2(SVCXPRT *transp, void *argp) 227{ 228 static char res; 229 230#ifdef DEBUG 231 if (debug) 232 printf("ypbindproc_null_2\n"); 233#endif 234 (void)memset(&res, 0, sizeof(res)); 235 return (void *)&res; 236} 237 238static void * 239ypbindproc_domain_2(SVCXPRT *transp, void *argp) 240{ 241 static struct ypbind_resp res; 242 struct _dom_binding *ypdb; 243 char *arg = *(char **) argp; 244 time_t now; 245 int count; 246 247#ifdef DEBUG 248 if (debug) 249 printf("ypbindproc_domain_2 %s\n", arg); 250#endif 251 if (_yp_invalid_domain(arg)) 252 return NULL; 253 254 (void)memset(&res, 0, sizeof res); 255 res.ypbind_status = YPBIND_FAIL_VAL; 256 257 for (count = 0, ypdb = ypbindlist; 258 ypdb != NULL; 259 ypdb = ypdb->dom_pnext, count++) { 260 if (count > 100) 261 return NULL; /* prevent denial of service */ 262 if (!strcmp(ypdb->dom_domain, arg)) 263 break; 264 } 265 266 if (ypdb == NULL) { 267 ypdb = makebinding(arg); 268 ypdb->dom_vers = YPVERS; 269 ypdb->dom_alive = 0; 270 ypdb->dom_lockfd = -1; 271 removelock(ypdb); 272 ypdb->dom_xid = unique_xid(ypdb); 273 ypdb->dom_pnext = ypbindlist; 274 ypbindlist = ypdb; 275 check++; 276#ifdef DEBUG 277 if (debug) 278 printf("unknown domain %s\n", arg); 279#endif 280 return NULL; 281 } 282 283 if (ypdb->dom_alive == 0) { 284#ifdef DEBUG 285 if (debug) 286 printf("dead domain %s\n", arg); 287#endif 288 return NULL; 289 } 290 291#ifdef HEURISTIC 292 time(&now); 293 if (now < ypdb->dom_ask_t + 5) { 294 /* 295 * Hmm. More than 2 requests in 5 seconds have indicated 296 * that my binding is possibly incorrect. 297 * Ok, do an immediate poll of the server. 298 */ 299 if (ypdb->dom_check_t >= now) { 300 /* don't flood it */ 301 ypdb->dom_check_t = 0; 302 check++; 303 } 304 } 305 ypdb->dom_ask_t = now; 306#endif 307 308 res.ypbind_status = YPBIND_SUCC_VAL; 309 res.ypbind_respbody.ypbind_bindinfo.ypbind_binding_addr.s_addr = 310 ypdb->dom_server_addr.sin_addr.s_addr; 311 res.ypbind_respbody.ypbind_bindinfo.ypbind_binding_port = 312 ypdb->dom_server_addr.sin_port; 313#ifdef DEBUG 314 if (debug) 315 printf("domain %s at %s/%d\n", ypdb->dom_domain, 316 inet_ntoa(ypdb->dom_server_addr.sin_addr), 317 ntohs(ypdb->dom_server_addr.sin_port)); 318#endif 319 return &res; 320} 321 322static void * 323ypbindproc_setdom_2(SVCXPRT *transp, void *argp) 324{ 325 struct ypbind_setdom *sd = argp; 326 struct sockaddr_in *fromsin, bindsin; 327 static bool_t res; 328 329#ifdef DEBUG 330 if (debug) 331 printf("ypbindproc_setdom_2 %s\n", inet_ntoa(bindsin.sin_addr)); 332#endif 333 (void)memset(&res, 0, sizeof(res)); 334 fromsin = svc_getcaller(transp); 335 336 switch (ypbindmode) { 337 case YPBIND_SETLOCAL: 338 if (fromsin->sin_addr.s_addr != htonl(INADDR_LOOPBACK)) { 339#ifdef DEBUG 340 if (debug) 341 printf("ypset from %s denied\n", 342 inet_ntoa(fromsin->sin_addr)); 343#endif 344 return NULL; 345 } 346 /* FALLTHROUGH */ 347 348 case YPBIND_SETALL: 349 been_ypset = 1; 350 break; 351 352 case YPBIND_DIRECT: 353 case YPBIND_BROADCAST: 354 default: 355#ifdef DEBUG 356 if (debug) 357 printf("ypset denied\n"); 358#endif 359 return NULL; 360 } 361 362 if (ntohs(fromsin->sin_port) >= IPPORT_RESERVED) { 363#ifdef DEBUG 364 if (debug) 365 printf("ypset from unprivileged port denied\n"); 366#endif 367 return &res; 368 } 369 370 if (sd->ypsetdom_vers != YPVERS) { 371#ifdef DEBUG 372 if (debug) 373 printf("ypset with wrong version denied\n"); 374#endif 375 return &res; 376 } 377 378 (void)memset(&bindsin, 0, sizeof bindsin); 379 bindsin.sin_family = AF_INET; 380 bindsin.sin_len = sizeof(bindsin); 381 bindsin.sin_addr = sd->ypsetdom_addr; 382 bindsin.sin_port = sd->ypsetdom_port; 383 rpc_received(sd->ypsetdom_domain, &bindsin, 1); 384 385#ifdef DEBUG 386 if (debug) 387 printf("ypset to %s succeeded\n", inet_ntoa(bindsin.sin_addr)); 388#endif 389 res = 1; 390 return &res; 391} 392 393static void 394ypbindprog_2(struct svc_req *rqstp, register SVCXPRT *transp) 395{ 396 union { 397 char ypbindproc_domain_2_arg[YPMAXDOMAIN + 1]; 398 struct ypbind_setdom ypbindproc_setdom_2_arg; 399 } argument; 400 struct authunix_parms *creds; 401 char *result; 402 xdrproc_t xdr_argument, xdr_result; 403 void *(*local)(SVCXPRT *, void *); 404 405 switch (rqstp->rq_proc) { 406 case YPBINDPROC_NULL: 407 xdr_argument = xdr_void; 408 xdr_result = xdr_void; 409 local = ypbindproc_null_2; 410 break; 411 412 case YPBINDPROC_DOMAIN: 413 xdr_argument = xdr_ypdomain_wrap_string; 414 xdr_result = xdr_ypbind_resp; 415 local = ypbindproc_domain_2; 416 break; 417 418 case YPBINDPROC_SETDOM: 419 switch (rqstp->rq_cred.oa_flavor) { 420 case AUTH_UNIX: 421 creds = (struct authunix_parms *)rqstp->rq_clntcred; 422 if (creds->aup_uid != 0) { 423 svcerr_auth(transp, AUTH_BADCRED); 424 return; 425 } 426 break; 427 default: 428 svcerr_auth(transp, AUTH_TOOWEAK); 429 return; 430 } 431 432 xdr_argument = xdr_ypbind_setdom; 433 xdr_result = xdr_void; 434 local = ypbindproc_setdom_2; 435 break; 436 437 default: 438 svcerr_noproc(transp); 439 return; 440 } 441 (void)memset(&argument, 0, sizeof(argument)); 442 if (!svc_getargs(transp, xdr_argument, (caddr_t)&argument)) { 443 svcerr_decode(transp); 444 return; 445 } 446 result = (*local)(transp, &argument); 447 if (result != NULL && !svc_sendreply(transp, xdr_result, result)) { 448 svcerr_systemerr(transp); 449 } 450 return; 451} 452 453int 454main(int argc, char *argv[]) 455{ 456 struct timeval tv; 457 fd_set fdsr; 458 int width, lockfd; 459 int evil = 0, one; 460 char pathname[MAXPATHLEN]; 461 struct stat st; 462 463 yp_get_default_domain(&domainname); 464 if (domainname[0] == '\0') 465 errx(1, "Domainname not set. Aborting."); 466 467 /* 468 * Per traditional ypbind(8) semantics, if a ypservers 469 * file does not exist, we default to broadcast mode. 470 * If the file does exist, we default to direct mode. 471 * Note that we can still override direct mode by passing 472 * the -broadcast flag. 473 */ 474 snprintf(pathname, sizeof(pathname), "%s/%s%s", BINDINGDIR, 475 domainname, YPSERVERSSUFF); 476 if (stat(pathname, &st) < 0) { 477#ifdef DEBUG 478 if (debug) 479 fprintf(stderr, 480 "%s does not exist, defaulting to broadcast\n", 481 pathname); 482#endif 483 ypbindmode = YPBIND_BROADCAST; 484 } else 485 ypbindmode = YPBIND_DIRECT; 486 487 while (--argc) { 488 ++argv; 489 if (!strcmp("-insecure", *argv)) 490 insecure = 1; 491 else if (!strcmp("-ypset", *argv)) 492 ypbindmode = YPBIND_SETALL; 493 else if (!strcmp("-ypsetme", *argv)) 494 ypbindmode = YPBIND_SETLOCAL; 495 else if (!strcmp("-broadcast", *argv)) 496 ypbindmode = YPBIND_BROADCAST; 497#ifdef DEBUG 498 else if (!strcmp("-d", *argv)) 499 debug++; 500#endif 501 else 502 usage(); 503 } 504 505 /* initialise syslog */ 506 openlog("ypbind", LOG_PERROR | LOG_PID, LOG_DAEMON); 507 508 /* blow away everything in BINDINGDIR */ 509 510 lockfd = open(_PATH_YPBIND_LOCK, O_CREAT|O_SHLOCK|O_RDWR|O_TRUNC, 0644); 511 if (lockfd == -1) 512 err(1, "Cannot create %s", _PATH_YPBIND_LOCK); 513 514#if O_SHLOCK == 0 515 (void)flock(lockfd, LOCK_SH); 516#endif 517 518 (void)pmap_unset(YPBINDPROG, YPBINDVERS); 519 520 udptransp = svcudp_create(RPC_ANYSOCK); 521 if (udptransp == NULL) 522 errx(1, "Cannot create udp service."); 523 524 if (!svc_register(udptransp, YPBINDPROG, YPBINDVERS, ypbindprog_2, 525 IPPROTO_UDP)) 526 errx(1, "Unable to register (YPBINDPROG, YPBINDVERS, udp)."); 527 528 tcptransp = svctcp_create(RPC_ANYSOCK, 0, 0); 529 if (tcptransp == NULL) 530 errx(1, "Cannot create tcp service."); 531 532 if (!svc_register(tcptransp, YPBINDPROG, YPBINDVERS, ypbindprog_2, 533 IPPROTO_TCP)) 534 errx(1, "Unable to register (YPBINDPROG, YPBINDVERS, tcp)."); 535 536 /* XXX use SOCK_STREAM for direct queries? */ 537 if ((rpcsock = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP)) == -1) 538 err(1, "rpc socket"); 539 if ((pingsock = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP)) == -1) 540 err(1, "ping socket"); 541 542 (void)fcntl(rpcsock, F_SETFL, fcntl(rpcsock, F_GETFL, 0) | FNDELAY); 543 (void)fcntl(pingsock, F_SETFL, fcntl(pingsock, F_GETFL, 0) | FNDELAY); 544 545 one = 1; 546 (void)setsockopt(rpcsock, SOL_SOCKET, SO_BROADCAST, &one, sizeof(one)); 547 rmtca.prog = YPPROG; 548 rmtca.vers = YPVERS; 549 rmtca.proc = YPPROC_DOMAIN_NONACK; 550 rmtca.xdr_args = NULL; /* set at call time */ 551 rmtca.args_ptr = NULL; /* set at call time */ 552 rmtcr.port_ptr = &rmtcr_port; 553 rmtcr.xdr_results = xdr_bool; 554 rmtcr.results_ptr = (caddr_t)&rmtcr_outval; 555 556 if (_yp_invalid_domain(domainname)) 557 errx(1, "bad domainname: %s", domainname); 558 559 /* build initial domain binding, make it "unsuccessful" */ 560 ypbindlist = makebinding(domainname); 561 ypbindlist->dom_vers = YPVERS; 562 ypbindlist->dom_alive = 0; 563 ypbindlist->dom_lockfd = -1; 564 removelock(ypbindlist); 565 566 checkwork(); 567 568 for (;;) { 569 width = svc_maxfd; 570 if (rpcsock > width) 571 width = rpcsock; 572 if (pingsock > width) 573 width = pingsock; 574 width++; 575 fdsr = svc_fdset; 576 FD_SET(rpcsock, &fdsr); 577 FD_SET(pingsock, &fdsr); 578 tv.tv_sec = 1; 579 tv.tv_usec = 0; 580 581 switch (select(width, &fdsr, NULL, NULL, &tv)) { 582 case 0: 583 checkwork(); 584 break; 585 case -1: 586 yp_log(LOG_WARNING, "select: %m"); 587 break; 588 default: 589 if (FD_ISSET(rpcsock, &fdsr)) 590 handle_replies(); 591 if (FD_ISSET(pingsock, &fdsr)) 592 handle_ping(); 593 svc_getreqset(&fdsr); 594 if (check) 595 checkwork(); 596 break; 597 } 598 599 if (!evil && ypbindlist->dom_alive) { 600 evil = 1; 601#ifdef DEBUG 602 if (!debug) 603#endif 604 daemon(0, 0); 605 pidfile(NULL); 606 } 607 } 608} 609 610/* 611 * State transition is done like this: 612 * 613 * STATE EVENT ACTION NEWSTATE TIMEOUT 614 * no binding timeout broadcast no binding 5 sec 615 * no binding answer -- binding 60 sec 616 * binding timeout ping server checking 5 sec 617 * checking timeout ping server + broadcast checking 5 sec 618 * checking answer -- binding 60 sec 619 */ 620void 621checkwork(void) 622{ 623 struct _dom_binding *ypdb; 624 time_t t; 625 626 check = 0; 627 628 time(&t); 629 for (ypdb = ypbindlist; ypdb; ypdb = ypdb->dom_pnext) { 630 if (ypdb->dom_check_t < t) { 631 if (ypdb->dom_alive == 1) 632 ping(ypdb); 633 else 634 nag_servers(ypdb); 635 time(&t); 636 ypdb->dom_check_t = t + 5; 637 } 638 } 639} 640 641int 642ping(struct _dom_binding *ypdb) 643{ 644 char *dom = ypdb->dom_domain; 645 struct rpc_msg msg; 646 char buf[BUFSIZE]; 647 enum clnt_stat st; 648 int outlen; 649 AUTH *rpcua; 650 XDR xdr; 651 652 (void)memset(&xdr, 0, sizeof xdr); 653 (void)memset(&msg, 0, sizeof msg); 654 655 rpcua = authunix_create_default(); 656 if (rpcua == NULL) { 657#ifdef DEBUG 658 if (debug) 659 printf("cannot get unix auth\n"); 660#endif 661 return RPC_SYSTEMERROR; 662 } 663 664 msg.rm_direction = CALL; 665 msg.rm_call.cb_rpcvers = RPC_MSG_VERSION; 666 msg.rm_call.cb_prog = YPPROG; 667 msg.rm_call.cb_vers = YPVERS; 668 msg.rm_call.cb_proc = YPPROC_DOMAIN_NONACK; 669 msg.rm_call.cb_cred = rpcua->ah_cred; 670 msg.rm_call.cb_verf = rpcua->ah_verf; 671 672 msg.rm_xid = ypdb->dom_xid; 673 xdrmem_create(&xdr, buf, sizeof buf, XDR_ENCODE); 674 if (!xdr_callmsg(&xdr, &msg)) { 675 st = RPC_CANTENCODEARGS; 676 AUTH_DESTROY(rpcua); 677 return st; 678 } 679 if (!xdr_ypdomain_wrap_string(&xdr, &dom)) { 680 st = RPC_CANTENCODEARGS; 681 AUTH_DESTROY(rpcua); 682 return st; 683 } 684 outlen = (int)xdr_getpos(&xdr); 685 xdr_destroy(&xdr); 686 if (outlen < 1) { 687 st = RPC_CANTENCODEARGS; 688 AUTH_DESTROY(rpcua); 689 return st; 690 } 691 AUTH_DESTROY(rpcua); 692 693 ypdb->dom_alive = 2; 694 if (sendto(pingsock, buf, outlen, 0, 695 (struct sockaddr *)&ypdb->dom_server_addr, 696 sizeof ypdb->dom_server_addr) == -1) 697 yp_log(LOG_WARNING, "ping: sendto: %m"); 698 return 0; 699 700} 701 702static int 703nag_servers(struct _dom_binding *ypdb) 704{ 705 char *dom = ypdb->dom_domain; 706 struct rpc_msg msg; 707 char buf[BUFSIZE]; 708 enum clnt_stat st; 709 int outlen; 710 AUTH *rpcua; 711 XDR xdr; 712 713 rmtca.xdr_args = xdr_ypdomain_wrap_string; 714 rmtca.args_ptr = (char *)&dom; 715 716 (void)memset(&xdr, 0, sizeof xdr); 717 (void)memset(&msg, 0, sizeof msg); 718 719 rpcua = authunix_create_default(); 720 if (rpcua == NULL) { 721#ifdef DEBUG 722 if (debug) 723 printf("cannot get unix auth\n"); 724#endif 725 return RPC_SYSTEMERROR; 726 } 727 msg.rm_direction = CALL; 728 msg.rm_call.cb_rpcvers = RPC_MSG_VERSION; 729 msg.rm_call.cb_prog = PMAPPROG; 730 msg.rm_call.cb_vers = PMAPVERS; 731 msg.rm_call.cb_proc = PMAPPROC_CALLIT; 732 msg.rm_call.cb_cred = rpcua->ah_cred; 733 msg.rm_call.cb_verf = rpcua->ah_verf; 734 735 msg.rm_xid = ypdb->dom_xid; 736 xdrmem_create(&xdr, buf, sizeof buf, XDR_ENCODE); 737 if (!xdr_callmsg(&xdr, &msg)) { 738 st = RPC_CANTENCODEARGS; 739 AUTH_DESTROY(rpcua); 740 return st; 741 } 742 if (!xdr_rmtcall_args(&xdr, &rmtca)) { 743 st = RPC_CANTENCODEARGS; 744 AUTH_DESTROY(rpcua); 745 return st; 746 } 747 outlen = (int)xdr_getpos(&xdr); 748 xdr_destroy(&xdr); 749 if (outlen < 1) { 750 st = RPC_CANTENCODEARGS; 751 AUTH_DESTROY(rpcua); 752 return st; 753 } 754 AUTH_DESTROY(rpcua); 755 756 if (ypdb->dom_lockfd != -1) { 757 (void)close(ypdb->dom_lockfd); 758 ypdb->dom_lockfd = -1; 759 removelock(ypdb); 760 } 761 762 if (ypdb->dom_alive == 2) { 763 /* 764 * This resolves the following situation: 765 * ypserver on other subnet was once bound, 766 * but rebooted and is now using a different port 767 */ 768 struct sockaddr_in bindsin; 769 770 memset(&bindsin, 0, sizeof bindsin); 771 bindsin.sin_family = AF_INET; 772 bindsin.sin_len = sizeof(bindsin); 773 bindsin.sin_port = htons(PMAPPORT); 774 bindsin.sin_addr = ypdb->dom_server_addr.sin_addr; 775 776 if (sendto(rpcsock, buf, outlen, 0, (struct sockaddr *)&bindsin, 777 sizeof bindsin) == -1) 778 yp_log(LOG_WARNING, "broadcast: sendto: %m"); 779 } 780 781 switch (ypbindmode) { 782 case YPBIND_SETALL: 783 case YPBIND_SETLOCAL: 784 if (been_ypset) 785 return direct_set(buf, outlen, ypdb); 786 /* FALLTHROUGH */ 787 788 case YPBIND_BROADCAST: 789 return broadcast(buf, outlen); 790 791 case YPBIND_DIRECT: 792 return direct(buf, outlen); 793 } 794 795 return -1; 796} 797 798static int 799broadcast(char *buf, int outlen) 800{ 801 struct ifaddrs *ifap, *ifa; 802 struct sockaddr_in bindsin; 803 struct in_addr in; 804 805 memset(&bindsin, 0, sizeof bindsin); 806 bindsin.sin_family = AF_INET; 807 bindsin.sin_len = sizeof(bindsin); 808 bindsin.sin_port = htons(PMAPPORT); 809 810 if (getifaddrs(&ifap) != 0) { 811 yp_log(LOG_WARNING, "broadcast: getifaddrs: %m"); 812 return (-1); 813 } 814 for (ifa = ifap; ifa; ifa = ifa->ifa_next) { 815 if (ifa->ifa_addr->sa_family != AF_INET) 816 continue; 817 if ((ifa->ifa_flags & IFF_UP) == 0) 818 continue; 819 820 switch (ifa->ifa_flags & (IFF_LOOPBACK | IFF_BROADCAST)) { 821 case IFF_BROADCAST: 822 if (!ifa->ifa_broadaddr) 823 continue; 824 if (ifa->ifa_broadaddr->sa_family != AF_INET) 825 continue; 826 in = ((struct sockaddr_in *)ifa->ifa_broadaddr)->sin_addr; 827 break; 828 case IFF_LOOPBACK: 829 in = ((struct sockaddr_in *)ifa->ifa_addr)->sin_addr; 830 break; 831 default: 832 continue; 833 } 834 835 bindsin.sin_addr = in; 836 if (sendto(rpcsock, buf, outlen, 0, (struct sockaddr *)&bindsin, 837 bindsin.sin_len) == -1) 838 yp_log(LOG_WARNING, "broadcast: sendto: %m"); 839 } 840 freeifaddrs(ifap); 841 return (0); 842} 843 844static int 845direct(char *buf, int outlen) 846{ 847 static FILE *df; 848 static char ypservers_path[MAXPATHLEN]; 849 char line[_POSIX2_LINE_MAX]; 850 char *p; 851 struct hostent *hp; 852 struct sockaddr_in bindsin; 853 int i, count = 0; 854 855 if (df) 856 rewind(df); 857 else { 858 snprintf(ypservers_path, sizeof(ypservers_path), 859 "%s/%s%s", BINDINGDIR, domainname, YPSERVERSSUFF); 860 df = fopen(ypservers_path, "r"); 861 if (df == NULL) { 862 yp_log(LOG_ERR, "%s: ", ypservers_path); 863 exit(1); 864 } 865 } 866 867 memset(&bindsin, 0, sizeof bindsin); 868 bindsin.sin_family = AF_INET; 869 bindsin.sin_len = sizeof(bindsin); 870 bindsin.sin_port = htons(PMAPPORT); 871 872 while(fgets(line, sizeof(line), df) != NULL) { 873 /* skip lines that are too big */ 874 p = strchr(line, '\n'); 875 if (p == NULL) { 876 int c; 877 878 while ((c = getc(df)) != '\n' && c != EOF) 879 ; 880 continue; 881 } 882 *p = '\0'; 883 p = line; 884 while (isspace(*p)) 885 p++; 886 if (*p == '#') 887 continue; 888 hp = gethostbyname(p); 889 if (!hp) { 890 yp_log(LOG_WARNING, "%s: %s", p, hstrerror(h_errno)); 891 continue; 892 } 893 /* step through all addresses in case first is unavailable */ 894 for (i = 0; hp->h_addr_list[i]; i++) { 895 memmove(&bindsin.sin_addr, hp->h_addr_list[0], 896 hp->h_length); 897 if (sendto(rpcsock, buf, outlen, 0, 898 (struct sockaddr *)&bindsin, sizeof bindsin) < 0) { 899 yp_log(LOG_WARNING, "direct: sendto: %m"); 900 continue; 901 } else 902 count++; 903 } 904 } 905 if (!count) { 906 yp_log(LOG_WARNING, "no contactable servers found in %s", 907 ypservers_path); 908 return -1; 909 } 910 return 0; 911} 912 913static int 914direct_set(char *buf, int outlen, struct _dom_binding *ypdb) 915{ 916 struct sockaddr_in bindsin; 917 char path[MAXPATHLEN]; 918 struct iovec iov[2]; 919 struct ypbind_resp ybr; 920 SVCXPRT dummy_svc; 921 int fd, bytes; 922 923 /* 924 * Gack, we lose if binding file went away. We reset 925 * "been_set" if this happens, otherwise we'll never 926 * bind again. 927 */ 928 snprintf(path, sizeof(path), "%s/%s.%ld", BINDINGDIR, 929 ypdb->dom_domain, ypdb->dom_vers); 930 931 if ((fd = open(path, O_SHLOCK|O_RDONLY, 0644)) == -1) { 932 yp_log(LOG_WARNING, "%s: %m", path); 933 been_ypset = 0; 934 return -1; 935 } 936 937#if O_SHLOCK == 0 938 (void)flock(fd, LOCK_SH); 939#endif 940 941 /* Read the binding file... */ 942 iov[0].iov_base = (caddr_t)&(dummy_svc.xp_port); 943 iov[0].iov_len = sizeof(dummy_svc.xp_port); 944 iov[1].iov_base = (caddr_t)&ybr; 945 iov[1].iov_len = sizeof(ybr); 946 bytes = readv(fd, iov, 2); 947 (void)close(fd); 948 if (bytes != (iov[0].iov_len + iov[1].iov_len)) { 949 /* Binding file corrupt? */ 950 yp_log(LOG_WARNING, "%s: %m", path); 951 been_ypset = 0; 952 return -1; 953 } 954 955 bindsin.sin_addr = 956 ybr.ypbind_respbody.ypbind_bindinfo.ypbind_binding_addr; 957 958 if (sendto(rpcsock, buf, outlen, 0, (struct sockaddr *)&bindsin, 959 sizeof(bindsin)) < 0) { 960 yp_log(LOG_WARNING, "direct_set: sendto: %m"); 961 return -1; 962 } 963 964 return 0; 965} 966 967static enum clnt_stat 968handle_replies(void) 969{ 970 char buf[BUFSIZE]; 971 int fromlen, inlen; 972 struct _dom_binding *ypdb; 973 struct sockaddr_in raddr; 974 struct rpc_msg msg; 975 XDR xdr; 976 977recv_again: 978 (void)memset(&xdr, 0, sizeof(xdr)); 979 (void)memset(&msg, 0, sizeof(msg)); 980 msg.acpted_rply.ar_verf = _null_auth; 981 msg.acpted_rply.ar_results.where = (caddr_t)&rmtcr; 982 msg.acpted_rply.ar_results.proc = xdr_rmtcallres; 983 984try_again: 985 fromlen = sizeof(struct sockaddr); 986 inlen = recvfrom(rpcsock, buf, sizeof buf, 0, 987 (struct sockaddr *)&raddr, &fromlen); 988 if (inlen < 0) { 989 if (errno == EINTR) 990 goto try_again; 991 return RPC_CANTRECV; 992 } 993 if (inlen < sizeof(u_int32_t)) 994 goto recv_again; 995 996 /* 997 * see if reply transaction id matches sent id. 998 * If so, decode the results. 999 */ 1000 xdrmem_create(&xdr, buf, (u_int)inlen, XDR_DECODE); 1001 if (xdr_replymsg(&xdr, &msg)) { 1002 if ((msg.rm_reply.rp_stat == MSG_ACCEPTED) && 1003 (msg.acpted_rply.ar_stat == SUCCESS)) { 1004 raddr.sin_port = htons((u_short)rmtcr_port); 1005 ypdb = xid2ypdb(msg.rm_xid); 1006 if (ypdb != NULL) 1007 rpc_received(ypdb->dom_domain, &raddr, 0); 1008 } 1009 } 1010 xdr.x_op = XDR_FREE; 1011 msg.acpted_rply.ar_results.proc = xdr_void; 1012 xdr_destroy(&xdr); 1013 1014 return RPC_SUCCESS; 1015} 1016 1017static enum clnt_stat 1018handle_ping(void) 1019{ 1020 char buf[BUFSIZE]; 1021 int fromlen, inlen; 1022 struct _dom_binding *ypdb; 1023 struct sockaddr_in raddr; 1024 struct rpc_msg msg; 1025 XDR xdr; 1026 bool_t res; 1027 1028recv_again: 1029 (void)memset(&xdr, 0, sizeof(xdr)); 1030 (void)memset(&msg, 0, sizeof(msg)); 1031 msg.acpted_rply.ar_verf = _null_auth; 1032 msg.acpted_rply.ar_results.where = (caddr_t)&res; 1033 msg.acpted_rply.ar_results.proc = xdr_bool; 1034 1035try_again: 1036 fromlen = sizeof (struct sockaddr); 1037 inlen = recvfrom(pingsock, buf, sizeof buf, 0, 1038 (struct sockaddr *)&raddr, &fromlen); 1039 if (inlen < 0) { 1040 if (errno == EINTR) 1041 goto try_again; 1042 return RPC_CANTRECV; 1043 } 1044 if (inlen < sizeof(u_int32_t)) 1045 goto recv_again; 1046 1047 /* 1048 * see if reply transaction id matches sent id. 1049 * If so, decode the results. 1050 */ 1051 xdrmem_create(&xdr, buf, (u_int)inlen, XDR_DECODE); 1052 if (xdr_replymsg(&xdr, &msg)) { 1053 if ((msg.rm_reply.rp_stat == MSG_ACCEPTED) && 1054 (msg.acpted_rply.ar_stat == SUCCESS)) { 1055 ypdb = xid2ypdb(msg.rm_xid); 1056 if (ypdb != NULL) 1057 rpc_received(ypdb->dom_domain, &raddr, 0); 1058 } 1059 } 1060 xdr.x_op = XDR_FREE; 1061 msg.acpted_rply.ar_results.proc = xdr_void; 1062 xdr_destroy(&xdr); 1063 1064 return RPC_SUCCESS; 1065} 1066 1067/* 1068 * LOOPBACK IS MORE IMPORTANT: PUT IN HACK 1069 */ 1070void 1071rpc_received(char *dom, struct sockaddr_in *raddrp, int force) 1072{ 1073 struct _dom_binding *ypdb; 1074 struct iovec iov[2]; 1075 struct ypbind_resp ybr; 1076 int fd; 1077 1078#ifdef DEBUG 1079 if (debug) 1080 printf("returned from %s about %s\n", 1081 inet_ntoa(raddrp->sin_addr), dom); 1082#endif 1083 1084 if (dom == NULL) 1085 return; 1086 1087 if (_yp_invalid_domain(dom)) 1088 return; 1089 1090 /* don't support insecure servers by default */ 1091 if (!insecure && ntohs(raddrp->sin_port) >= IPPORT_RESERVED) 1092 return; 1093 1094 for (ypdb = ypbindlist; ypdb; ypdb = ypdb->dom_pnext) 1095 if (!strcmp(ypdb->dom_domain, dom)) 1096 break; 1097 1098 if (ypdb == NULL) { 1099 if (force == 0) 1100 return; 1101 ypdb = makebinding(dom); 1102 ypdb->dom_lockfd = -1; 1103 ypdb->dom_pnext = ypbindlist; 1104 ypbindlist = ypdb; 1105 } 1106 1107 /* soft update, alive */ 1108 if (ypdb->dom_alive == 1 && force == 0) { 1109 if (!memcmp(&ypdb->dom_server_addr, raddrp, 1110 sizeof ypdb->dom_server_addr)) { 1111 ypdb->dom_alive = 1; 1112 /* recheck binding in 60 sec */ 1113 ypdb->dom_check_t = time(NULL) + 60; 1114 } 1115 return; 1116 } 1117 1118 (void)memcpy(&ypdb->dom_server_addr, raddrp, 1119 sizeof ypdb->dom_server_addr); 1120 /* recheck binding in 60 seconds */ 1121 ypdb->dom_check_t = time(NULL) + 60; 1122 ypdb->dom_vers = YPVERS; 1123 ypdb->dom_alive = 1; 1124 1125 if (ypdb->dom_lockfd != -1) 1126 (void)close(ypdb->dom_lockfd); 1127 1128 if ((fd = makelock(ypdb)) == -1) 1129 return; 1130 1131 /* 1132 * ok, if BINDINGDIR exists, and we can create the binding file, 1133 * then write to it.. 1134 */ 1135 ypdb->dom_lockfd = fd; 1136 1137 iov[0].iov_base = (caddr_t)&(udptransp->xp_port); 1138 iov[0].iov_len = sizeof udptransp->xp_port; 1139 iov[1].iov_base = (caddr_t)&ybr; 1140 iov[1].iov_len = sizeof ybr; 1141 1142 (void)memset(&ybr, 0, sizeof ybr); 1143 ybr.ypbind_status = YPBIND_SUCC_VAL; 1144 ybr.ypbind_respbody.ypbind_bindinfo.ypbind_binding_addr = 1145 raddrp->sin_addr; 1146 ybr.ypbind_respbody.ypbind_bindinfo.ypbind_binding_port = 1147 raddrp->sin_port; 1148 1149 if (writev(ypdb->dom_lockfd, iov, 2) != 1150 iov[0].iov_len + iov[1].iov_len) { 1151 yp_log(LOG_WARNING, "writev: %m"); 1152 (void)close(ypdb->dom_lockfd); 1153 removelock(ypdb); 1154 ypdb->dom_lockfd = -1; 1155 } 1156} 1157 1158static struct _dom_binding * 1159xid2ypdb(u_int32_t xid) 1160{ 1161 struct _dom_binding *ypdb; 1162 1163 for (ypdb = ypbindlist; ypdb; ypdb = ypdb->dom_pnext) 1164 if (ypdb->dom_xid == xid) 1165 break; 1166 return (ypdb); 1167} 1168 1169static u_int32_t 1170unique_xid(struct _dom_binding *ypdb) 1171{ 1172 u_int32_t tmp_xid; 1173 1174 tmp_xid = (u_int32_t)(((u_long)ypdb) & 0xffffffff); 1175 while (xid2ypdb(tmp_xid) != NULL) 1176 tmp_xid++; 1177 1178 return tmp_xid; 1179} 1180