xref: /netbsd-src/usr.sbin/ypbind/ypbind.c (revision ae9172d6cd9432a6a1a56760d86b32c57a66c39c)
1 /*
2  * Copyright (c) 1992, 1993 Theo de Raadt <deraadt@fsa.ca>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by Theo de Raadt.
16  * 4. The name of the author may not be used to endorse or promote
17  *    products derived from this software without specific prior written
18  *    permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
21  * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
22  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
24  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 
33 #ifndef LINT
34 static char rcsid[] = "$Id: ypbind.c,v 1.13 1994/09/28 01:39:54 deraadt Exp $";
35 #endif
36 
37 #include <sys/param.h>
38 #include <sys/types.h>
39 #include <sys/ioctl.h>
40 #include <sys/signal.h>
41 #include <sys/socket.h>
42 #include <sys/file.h>
43 #include <sys/fcntl.h>
44 #include <sys/uio.h>
45 #include <sys/syslog.h>
46 #include <stdio.h>
47 #include <errno.h>
48 #include <ctype.h>
49 #include <dirent.h>
50 #include <netdb.h>
51 #include <string.h>
52 #include <rpc/rpc.h>
53 #include <rpc/xdr.h>
54 #include <net/if.h>
55 #include <arpa/inet.h>
56 #include <rpc/pmap_clnt.h>
57 #include <rpc/pmap_prot.h>
58 #include <rpc/pmap_rmt.h>
59 #include <unistd.h>
60 #include <rpcsvc/yp_prot.h>
61 #include <rpcsvc/ypclnt.h>
62 
63 #define BINDINGDIR	"/var/yp/binding"
64 #define YPBINDLOCK	"/var/run/ypbind.lock"
65 
66 struct _dom_binding {
67 	struct _dom_binding *dom_pnext;
68 	char dom_domain[YPMAXDOMAIN + 1];
69 	struct sockaddr_in dom_server_addr;
70 	unsigned short int dom_server_port;
71 	int dom_socket;
72 	CLIENT *dom_client;
73 	long int dom_vers;
74 	time_t dom_check_t;
75 	time_t dom_ask_t;
76 	int dom_lockfd;
77 	int dom_alive;
78 };
79 
80 extern bool_t xdr_domainname(), xdr_ypbind_resp();
81 extern bool_t xdr_ypreq_key(), xdr_ypresp_val();
82 extern bool_t xdr_ypbind_setdom();
83 
84 char *domainname;
85 
86 struct _dom_binding *ypbindlist;
87 int check;
88 
89 #define YPSET_NO	0
90 #define YPSET_LOCAL	1
91 #define YPSET_ALL	2
92 int ypsetmode = YPSET_NO;
93 
94 int rpcsock, pingsock;
95 struct rmtcallargs rmtca;
96 struct rmtcallres rmtcr;
97 char rmtcr_outval;
98 u_long rmtcr_port;
99 SVCXPRT *udptransp, *tcptransp;
100 
101 void *
102 ypbindproc_null_2(transp, argp, clnt)
103 SVCXPRT *transp;
104 void *argp;
105 CLIENT *clnt;
106 {
107 	static char res;
108 
109 	bzero((char *)&res, sizeof(res));
110 	return (void *)&res;
111 }
112 
113 struct ypbind_resp *
114 ypbindproc_domain_2(transp, argp, clnt)
115 SVCXPRT *transp;
116 char *argp;
117 CLIENT *clnt;
118 {
119 	static struct ypbind_resp res;
120 	struct _dom_binding *ypdb;
121 	char path[MAXPATHLEN];
122 	time_t now;
123 
124 	bzero((char *)&res, sizeof res);
125 	res.ypbind_status = YPBIND_FAIL_VAL;
126 
127 	for(ypdb=ypbindlist; ypdb; ypdb=ypdb->dom_pnext)
128 		if( strcmp(ypdb->dom_domain, argp) == 0)
129 			break;
130 
131 	if(ypdb==NULL) {
132 		ypdb = (struct _dom_binding *)malloc(sizeof *ypdb);
133 		bzero((char *)ypdb, sizeof *ypdb);
134 		strncpy(ypdb->dom_domain, argp, sizeof ypdb->dom_domain);
135 		ypdb->dom_vers = YPVERS;
136 		ypdb->dom_alive = 0;
137 		ypdb->dom_lockfd = -1;
138 		sprintf(path, "%s/%s.%d", BINDINGDIR, ypdb->dom_domain, ypdb->dom_vers);
139 		unlink(path);
140 		ypdb->dom_pnext = ypbindlist;
141 		ypbindlist = ypdb;
142 		check++;
143 		return NULL;
144 	}
145 
146 	if(ypdb->dom_alive==0)
147 		return NULL;
148 
149 #ifdef HEURISTIC
150 	time(&now);
151 	if (now < ypdb->dom_ask_t + 5) {
152 		/*
153 		 * Hmm. More than 2 requests in 5 seconds have indicated
154 		 * that my binding is possibly incorrect.
155 		 * Ok, do an immediate poll of the server.
156 		 */
157 		if (ypdb->dom_check_t >= now) {
158 			/* don't flood it */
159 			ypdb->dom_check_t = 0;
160 			check++;
161 		}
162 	}
163 	ypdb->dom_ask_t = now;
164 #endif
165 
166 answer:
167 	res.ypbind_status = YPBIND_SUCC_VAL;
168 	res.ypbind_respbody.ypbind_bindinfo.ypbind_binding_addr.s_addr =
169 		ypdb->dom_server_addr.sin_addr.s_addr;
170 	res.ypbind_respbody.ypbind_bindinfo.ypbind_binding_port =
171 		ypdb->dom_server_port;
172 	/*printf("domain %s at %s/%d\n", ypdb->dom_domain,
173 		inet_ntoa(ypdb->dom_server_addr.sin_addr),
174 		ntohs(ypdb->dom_server_addr.sin_port));*/
175 	return &res;
176 }
177 
178 bool_t *
179 ypbindproc_setdom_2(transp, argp, clnt)
180 SVCXPRT *transp;
181 struct ypbind_setdom *argp;
182 CLIENT *clnt;
183 {
184 	struct sockaddr_in *fromsin, bindsin;
185 	static bool_t res;
186 
187 	bzero((char *)&res, sizeof(res));
188 	fromsin = svc_getcaller(transp);
189 
190 	switch(ypsetmode) {
191 	case YPSET_LOCAL:
192 		if( fromsin->sin_addr.s_addr != htonl(INADDR_LOOPBACK))
193 			return (bool_t *)NULL;
194 		break;
195 	case YPSET_ALL:
196 		break;
197 	case YPSET_NO:
198 	default:
199 		return (bool_t *)NULL;
200 	}
201 
202 	if(ntohs(fromsin->sin_port) >= IPPORT_RESERVED)
203 		return &res;
204 
205 	if(argp->ypsetdom_vers != YPVERS)
206 		return &res;
207 
208 	bzero((char *)&bindsin, sizeof bindsin);
209 	bindsin.sin_family = AF_INET;
210 	bindsin.sin_addr.s_addr = argp->ypsetdom_addr.s_addr;
211 	bindsin.sin_port = argp->ypsetdom_port;
212 	rpc_received(argp->ypsetdom_domain, &bindsin, 1);
213 
214 	res = 1;
215 	return &res;
216 }
217 
218 static void
219 ypbindprog_2(rqstp, transp)
220 struct svc_req *rqstp;
221 register SVCXPRT *transp;
222 {
223 	union {
224 		char ypbindproc_domain_2_arg[MAXHOSTNAMELEN];
225 		struct ypbind_setdom ypbindproc_setdom_2_arg;
226 	} argument;
227 	struct authunix_parms *creds;
228 	char *result;
229 	bool_t (*xdr_argument)(), (*xdr_result)();
230 	char *(*local)();
231 
232 	switch (rqstp->rq_proc) {
233 	case YPBINDPROC_NULL:
234 		xdr_argument = xdr_void;
235 		xdr_result = xdr_void;
236 		local = (char *(*)()) ypbindproc_null_2;
237 		break;
238 
239 	case YPBINDPROC_DOMAIN:
240 		xdr_argument = xdr_domainname;
241 		xdr_result = xdr_ypbind_resp;
242 		local = (char *(*)()) ypbindproc_domain_2;
243 		break;
244 
245 	case YPBINDPROC_SETDOM:
246 		switch(rqstp->rq_cred.oa_flavor) {
247 		case AUTH_UNIX:
248 			creds = (struct authunix_parms *)rqstp->rq_clntcred;
249 			if( creds->aup_uid != 0) {
250 				svcerr_auth(transp, AUTH_BADCRED);
251 				return;
252 			}
253 			break;
254 		default:
255 			svcerr_auth(transp, AUTH_TOOWEAK);
256 			return;
257 		}
258 
259 		xdr_argument = xdr_ypbind_setdom;
260 		xdr_result = xdr_void;
261 		local = (char *(*)()) ypbindproc_setdom_2;
262 		break;
263 
264 	default:
265 		svcerr_noproc(transp);
266 		return;
267 	}
268 	bzero((char *)&argument, sizeof(argument));
269 	if (!svc_getargs(transp, xdr_argument, &argument)) {
270 		svcerr_decode(transp);
271 		return;
272 	}
273 	result = (*local)(transp, &argument, rqstp);
274 	if (result != NULL && !svc_sendreply(transp, xdr_result, result)) {
275 		svcerr_systemerr(transp);
276 	}
277 	return;
278 }
279 
280 main(argc, argv)
281 char **argv;
282 {
283 	char path[MAXPATHLEN];
284 	struct timeval tv;
285 	fd_set fdsr;
286 	int width, lockfd;
287 	int i;
288 
289 	yp_get_default_domain(&domainname);
290 	if( domainname[0] == '\0') {
291 		fprintf(stderr, "domainname not set. Aborting.\n");
292 		exit(1);
293 	}
294 
295 	for(i=1; i<argc; i++) {
296 		if( strcmp("-ypset", argv[i]) == 0)
297 			ypsetmode = YPSET_ALL;
298 		else if (strcmp("-ypsetme", argv[i]) == 0)
299 			ypsetmode = YPSET_LOCAL;
300 	}
301 
302 	/* blow away everything in BINDINGDIR */
303 
304 #ifdef O_SHLOCK
305 	lockfd = open(YPBINDLOCK, O_CREAT|O_SHLOCK|O_RDWR|O_TRUNC, 0644);
306 	if (lockfd == -1) {
307 		fprintf(stderr, "ypbind: cannot create %s\n", YPBINDLOCK);
308 		exit(1);
309 	}
310 #else
311 	lockfd = open(YPBINDLOCK, O_CREAT|O_RDWR|O_TRUNC, 0644);
312 	if (lockfd == -1) {
313 		fprintf(stderr, "ypbind: cannot create %s\n", YPBINDLOCK);
314 		exit(1);
315 	}
316 	flock(lockfd, LOCK_SH);
317 #endif
318 
319 #ifdef DAEMON
320 	switch(fork()) {
321 	case 0:
322 		break;
323 	case -1:
324 		perror("fork");
325 		exit(1);
326 	default:
327 		exit(0);
328 	}
329 	setsid();
330 #endif
331 
332 	pmap_unset(YPBINDPROG, YPBINDVERS);
333 
334 	udptransp = svcudp_create(RPC_ANYSOCK);
335 	if (udptransp == NULL) {
336 		fprintf(stderr, "cannot create udp service.");
337 		exit(1);
338 	}
339 	if (!svc_register(udptransp, YPBINDPROG, YPBINDVERS, ypbindprog_2,
340 	    IPPROTO_UDP)) {
341 		fprintf(stderr, "unable to register (YPBINDPROG, YPBINDVERS, udp).");
342 		exit(1);
343 	}
344 
345 	tcptransp = svctcp_create(RPC_ANYSOCK, 0, 0);
346 	if (tcptransp == NULL) {
347 		fprintf(stderr, "cannot create tcp service.");
348 		exit(1);
349 	}
350 
351 	if (!svc_register(tcptransp, YPBINDPROG, YPBINDVERS, ypbindprog_2,
352 	    IPPROTO_TCP)) {
353 		fprintf(stderr, "unable to register (YPBINDPROG, YPBINDVERS, tcp).");
354 		exit(1);
355 	}
356 
357 	if( (rpcsock=socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP)) < 0) {
358 		perror("socket");
359 		return -1;
360 	}
361 	if( (pingsock=socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP)) < 0) {
362 		perror("socket");
363 		return -1;
364 	}
365 
366 	fcntl(rpcsock, F_SETFL, fcntl(rpcsock, F_GETFL, 0) | FNDELAY);
367 	fcntl(pingsock, F_SETFL, fcntl(rpcsock, F_GETFL, 0) | FNDELAY);
368 	i = 1;
369 	setsockopt(rpcsock, SOL_SOCKET, SO_BROADCAST, &i, sizeof(i));
370 	rmtca.prog = YPPROG;
371 	rmtca.vers = YPVERS;
372 	rmtca.proc = YPPROC_DOMAIN_NONACK;
373 	rmtca.xdr_args = NULL;		/* set at call time */
374 	rmtca.args_ptr = NULL;		/* set at call time */
375 	rmtcr.port_ptr = &rmtcr_port;
376 	rmtcr.xdr_results = xdr_bool;
377 	rmtcr.results_ptr = (caddr_t)&rmtcr_outval;
378 
379 	/* build initial domain binding, make it "unsuccessful" */
380 	ypbindlist = (struct _dom_binding *)malloc(sizeof *ypbindlist);
381 	bzero((char *)ypbindlist, sizeof *ypbindlist);
382 	strncpy(ypbindlist->dom_domain, domainname, sizeof ypbindlist->dom_domain);
383 	ypbindlist->dom_vers = YPVERS;
384 	ypbindlist->dom_alive = 0;
385 	ypbindlist->dom_lockfd = -1;
386 	sprintf(path, "%s/%s.%d", BINDINGDIR, ypbindlist->dom_domain,
387 		ypbindlist->dom_vers);
388 	(void)unlink(path);
389 
390 	checkwork();
391 
392 	width = getdtablesize();
393 	while(1) {
394 		fdsr = svc_fdset;
395 		FD_SET(rpcsock, &fdsr);
396 		FD_SET(pingsock, &fdsr);
397 		tv.tv_sec = 1;
398 		tv.tv_usec = 0;
399 
400 		switch(select(width, &fdsr, NULL, NULL, &tv)) {
401 		case 0:
402 			checkwork();
403 			break;
404 		case -1:
405 			perror("select\n");
406 			break;
407 		default:
408 			if(FD_ISSET(rpcsock, &fdsr)) {
409 				FD_CLR(rpcsock, &fdsr);
410 				handle_replies();
411 			}
412 			if (FD_ISSET(pingsock, &fdsr)) {
413 				FD_CLR(pingsock, &fdsr);
414 				handle_ping();
415 			}
416 			svc_getreqset(&fdsr);
417 			if(check)
418 				checkwork();
419 			break;
420 		}
421 	}
422 }
423 
424 /*
425  * State transition is done like this:
426  *
427  * STATE	EVENT		ACTION			NEWSTATE	TIMEOUT
428  * no binding	timeout		broadcast 		no binding	5 sec
429  * no binding	answer		--			binding		60 sec
430  * binding	timeout		ping server		checking	5 sec
431  * checking	timeout		ping server + broadcast	checking	5 sec
432  * checking	answer		--			binding		60 sec
433  */
434 checkwork()
435 {
436 	struct _dom_binding *ypdb;
437 	time_t t;
438 
439 	check = 0;
440 
441 	time(&t);
442 	for(ypdb=ypbindlist; ypdb; ypdb=ypdb->dom_pnext) {
443 		if(ypdb->dom_check_t < t) {
444 			if (ypdb->dom_alive == 1)
445 				ping(ypdb);
446 			else
447 				broadcast(ypdb);
448 			time(&t);
449 			ypdb->dom_check_t = t + 5;
450 		}
451 	}
452 }
453 
454 ping(ypdb)
455 	struct _dom_binding *ypdb;
456 {
457 	char *dom = ypdb->dom_domain;
458 	struct rpc_msg rpcmsg;
459 	char buf[1400];
460 	enum clnt_stat st;
461 	int outlen;
462 	AUTH *rpcua;
463 	XDR rpcxdr;
464 
465 	bzero((char *)&rpcxdr, sizeof rpcxdr);
466 	bzero((char *)&rpcmsg, sizeof rpcmsg);
467 
468 	rpcua = authunix_create_default();
469 	if( rpcua == (AUTH *)NULL) {
470 		/*printf("cannot get unix auth\n");*/
471 		return RPC_SYSTEMERROR;
472 	}
473 	rpcmsg.rm_direction = CALL;
474 	rpcmsg.rm_call.cb_rpcvers = RPC_MSG_VERSION;
475 	rpcmsg.rm_call.cb_prog = YPPROG;
476 	rpcmsg.rm_call.cb_vers = YPVERS;
477 	rpcmsg.rm_call.cb_proc = YPPROC_DOMAIN_NONACK;
478 	rpcmsg.rm_call.cb_cred = rpcua->ah_cred;
479 	rpcmsg.rm_call.cb_verf = rpcua->ah_verf;
480 
481 	rpcmsg.rm_xid = (int)dom;
482 	xdrmem_create(&rpcxdr, buf, sizeof buf, XDR_ENCODE);
483 	if( (!xdr_callmsg(&rpcxdr, &rpcmsg)) ) {
484 		st = RPC_CANTENCODEARGS;
485 		AUTH_DESTROY(rpcua);
486 		return st;
487 	}
488 	if( (!xdr_domainname(&rpcxdr, dom)) ) {
489 		st = RPC_CANTENCODEARGS;
490 		AUTH_DESTROY(rpcua);
491 		return st;
492 	}
493 	outlen = (int)xdr_getpos(&rpcxdr);
494 	xdr_destroy(&rpcxdr);
495 	if(outlen<1) {
496 		st = RPC_CANTENCODEARGS;
497 		AUTH_DESTROY(rpcua);
498 		return st;
499 	}
500 	AUTH_DESTROY(rpcua);
501 
502 	ypdb->dom_alive = 2;
503 	if (sendto(pingsock, buf, outlen, 0,
504 		   (struct sockaddr *)&ypdb->dom_server_addr,
505 		   sizeof ypdb->dom_server_addr) < 0)
506 		perror("sendto");
507 	return 0;
508 
509 }
510 
511 broadcast(ypdb)
512 	struct _dom_binding *ypdb;
513 {
514 	char *dom = ypdb->dom_domain;
515 	struct rpc_msg rpcmsg;
516 	char buf[1400], inbuf[8192];
517 	char path[MAXPATHLEN];
518 	enum clnt_stat st;
519 	int outlen, i, sock, len;
520 	struct sockaddr_in bsin;
521 	struct ifconf ifc;
522 	struct ifreq ifreq, *ifr;
523 	struct in_addr in;
524 	AUTH *rpcua;
525 	XDR rpcxdr;
526 
527 	rmtca.xdr_args = xdr_domainname;
528 	rmtca.args_ptr = dom;
529 
530 	bzero((char *)&rpcxdr, sizeof rpcxdr);
531 	bzero((char *)&rpcmsg, sizeof rpcmsg);
532 
533 	rpcua = authunix_create_default();
534 	if( rpcua == (AUTH *)NULL) {
535 		/*printf("cannot get unix auth\n");*/
536 		return RPC_SYSTEMERROR;
537 	}
538 	rpcmsg.rm_direction = CALL;
539 	rpcmsg.rm_call.cb_rpcvers = RPC_MSG_VERSION;
540 	rpcmsg.rm_call.cb_prog = PMAPPROG;
541 	rpcmsg.rm_call.cb_vers = PMAPVERS;
542 	rpcmsg.rm_call.cb_proc = PMAPPROC_CALLIT;
543 	rpcmsg.rm_call.cb_cred = rpcua->ah_cred;
544 	rpcmsg.rm_call.cb_verf = rpcua->ah_verf;
545 
546 	rpcmsg.rm_xid = (int)dom;
547 	xdrmem_create(&rpcxdr, buf, sizeof buf, XDR_ENCODE);
548 	if( (!xdr_callmsg(&rpcxdr, &rpcmsg)) ) {
549 		st = RPC_CANTENCODEARGS;
550 		AUTH_DESTROY(rpcua);
551 		return st;
552 	}
553 	if( (!xdr_rmtcall_args(&rpcxdr, &rmtca)) ) {
554 		st = RPC_CANTENCODEARGS;
555 		AUTH_DESTROY(rpcua);
556 		return st;
557 	}
558 	outlen = (int)xdr_getpos(&rpcxdr);
559 	xdr_destroy(&rpcxdr);
560 	if(outlen<1) {
561 		st = RPC_CANTENCODEARGS;
562 		AUTH_DESTROY(rpcua);
563 		return st;
564 	}
565 	AUTH_DESTROY(rpcua);
566 
567 	if(ypdb->dom_lockfd!=-1) {
568 		close(ypdb->dom_lockfd);
569 		ypdb->dom_lockfd = -1;
570 		sprintf(path, "%s/%s.%d", BINDINGDIR,
571 			ypdb->dom_domain, ypdb->dom_vers);
572 		unlink(path);
573 	}
574 
575 	bzero((char *)&bsin, sizeof bsin);
576 	bsin.sin_family = AF_INET;
577 	bsin.sin_port = htons(PMAPPORT);
578 
579 	if (ypdb->dom_alive == 2) {
580 		/*
581 		 * This resolves the following situation:
582 		 * ypserver on other subnet was once bound,
583 		 * but rebooted and is now using a different port
584 		 */
585 		bsin.sin_addr = ypdb->dom_server_addr.sin_addr;
586 		if (sendto(rpcsock, buf, outlen, 0, (struct sockaddr *)&bsin,
587 			   sizeof bsin) < 0)
588 			perror("sendto");
589 	}
590 	/* find all networks and send the RPC packet out them all */
591 	if( (sock = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP)) < 0) {
592 		perror("socket");
593 		return -1;
594 	}
595 
596 	ifc.ifc_len = sizeof inbuf;
597 	ifc.ifc_buf = inbuf;
598 	if( ioctl(sock, SIOCGIFCONF, &ifc) < 0) {
599 		close(sock);
600 		perror("ioctl(SIOCGIFCONF)");
601 		return -1;
602 	}
603 	ifr = ifc.ifc_req;
604 	ifreq.ifr_name[0] = '\0';
605 	for(i=0; i<ifc.ifc_len; i+=len, ifr=(struct ifreq *)((caddr_t)ifr+len)) {
606 #if defined(BSD) && BSD >= 199103
607 		len = sizeof ifr->ifr_name + ifr->ifr_addr.sa_len;
608 #else
609 		len = sizeof ifc.ifc_len / sizeof(struct ifreq);
610 #endif
611 		ifreq = *ifr;
612 		if( ifreq.ifr_addr.sa_family != AF_INET)
613 			continue;
614 		if( ioctl(sock, SIOCGIFFLAGS, &ifreq) < 0) {
615 			perror("ioctl(SIOCGIFFLAGS)");
616 			continue;
617 		}
618 		if( (ifreq.ifr_flags & IFF_UP) == 0)
619 			continue;
620 
621 		ifreq.ifr_flags &= (IFF_LOOPBACK | IFF_BROADCAST);
622 		if( ifreq.ifr_flags==IFF_BROADCAST ) {
623 			if( ioctl(sock, SIOCGIFBRDADDR, &ifreq) < 0 ) {
624 				perror("ioctl(SIOCGIFBRDADDR)");
625 				continue;
626 			}
627 		} else if( ifreq.ifr_flags==IFF_LOOPBACK ) {
628 			if( ioctl(sock, SIOCGIFADDR, &ifreq) < 0 ) {
629 				perror("ioctl(SIOCGIFADDR)");
630 				continue;
631 			}
632 		} else
633 			continue;
634 
635 		in = ((struct sockaddr_in *)&ifreq.ifr_addr)->sin_addr;
636 		bsin.sin_addr = in;
637 		if( sendto(rpcsock, buf, outlen, 0, (struct sockaddr *)&bsin,
638 			   sizeof bsin) < 0 )
639 			perror("sendto");
640 	}
641 	close(sock);
642 	return 0;
643 }
644 
645 /*enum clnt_stat*/
646 handle_replies()
647 {
648 	char buf[1400];
649 	int fromlen, inlen;
650 	struct sockaddr_in raddr;
651 	struct rpc_msg msg;
652 	XDR xdr;
653 
654 recv_again:
655 	bzero((char *)&xdr, sizeof(xdr));
656 	bzero((char *)&msg, sizeof(msg));
657 	msg.acpted_rply.ar_verf = _null_auth;
658 	msg.acpted_rply.ar_results.where = (caddr_t)&rmtcr;
659 	msg.acpted_rply.ar_results.proc = xdr_rmtcallres;
660 
661 try_again:
662 	fromlen = sizeof (struct sockaddr);
663 	inlen = recvfrom(rpcsock, buf, sizeof buf, 0,
664 		(struct sockaddr *)&raddr, &fromlen);
665 	if(inlen<0) {
666 		if(errno==EINTR)
667 			goto try_again;
668 		return RPC_CANTRECV;
669 	}
670 	if(inlen<sizeof(u_long))
671 		goto recv_again;
672 
673 	/*
674 	 * see if reply transaction id matches sent id.
675 	 * If so, decode the results.
676 	 */
677 	xdrmem_create(&xdr, buf, (u_int)inlen, XDR_DECODE);
678 	if( xdr_replymsg(&xdr, &msg)) {
679 		if( (msg.rm_reply.rp_stat == MSG_ACCEPTED) &&
680 		   (msg.acpted_rply.ar_stat == SUCCESS)) {
681 			raddr.sin_port = htons((u_short)rmtcr_port);
682 			rpc_received(msg.rm_xid, &raddr, 0);
683 		}
684 	}
685 	xdr.x_op = XDR_FREE;
686 	msg.acpted_rply.ar_results.proc = xdr_void;
687 	xdr_destroy(&xdr);
688 
689 	return RPC_SUCCESS;
690 }
691 
692 /*enum clnt_stat*/
693 handle_ping()
694 {
695 	char buf[1400];
696 	int fromlen, inlen;
697 	struct sockaddr_in raddr;
698 	struct rpc_msg msg;
699 	XDR xdr;
700 	bool_t res;
701 
702 recv_again:
703 	bzero((char *)&xdr, sizeof(xdr));
704 	bzero((char *)&msg, sizeof(msg));
705 	msg.acpted_rply.ar_verf = _null_auth;
706 	msg.acpted_rply.ar_results.where = (caddr_t)&res;
707 	msg.acpted_rply.ar_results.proc = xdr_bool;
708 
709 try_again:
710 	fromlen = sizeof (struct sockaddr);
711 	inlen = recvfrom(pingsock, buf, sizeof buf, 0,
712 		(struct sockaddr *)&raddr, &fromlen);
713 	if(inlen<0) {
714 		if(errno==EINTR)
715 			goto try_again;
716 		return RPC_CANTRECV;
717 	}
718 	if(inlen<sizeof(u_long))
719 		goto recv_again;
720 
721 	/*
722 	 * see if reply transaction id matches sent id.
723 	 * If so, decode the results.
724 	 */
725 	xdrmem_create(&xdr, buf, (u_int)inlen, XDR_DECODE);
726 	if( xdr_replymsg(&xdr, &msg)) {
727 		if( (msg.rm_reply.rp_stat == MSG_ACCEPTED) &&
728 		   (msg.acpted_rply.ar_stat == SUCCESS)) {
729 			rpc_received(msg.rm_xid, &raddr, 0);
730 		}
731 	}
732 	xdr.x_op = XDR_FREE;
733 	msg.acpted_rply.ar_results.proc = xdr_void;
734 	xdr_destroy(&xdr);
735 
736 	return RPC_SUCCESS;
737 }
738 
739 /*
740  * LOOPBACK IS MORE IMPORTANT: PUT IN HACK
741  */
742 rpc_received(dom, raddrp, force)
743 char *dom;
744 struct sockaddr_in *raddrp;
745 int force;
746 {
747 	struct _dom_binding *ypdb;
748 	struct iovec iov[2];
749 	struct ypbind_resp ybr;
750 	char path[MAXPATHLEN];
751 	int fd;
752 
753 	/*printf("returned from %s about %s\n", inet_ntoa(raddrp->sin_addr), dom);*/
754 
755 	if(dom==NULL)
756 		return;
757 
758 	for(ypdb=ypbindlist; ypdb; ypdb=ypdb->dom_pnext)
759 		if( strcmp(ypdb->dom_domain, dom) == 0)
760 			break;
761 
762 	if(ypdb==NULL) {
763 		if(force==0)
764 			return;
765 		ypdb = (struct _dom_binding *)malloc(sizeof *ypdb);
766 		bzero((char *)ypdb, sizeof *ypdb);
767 		strncpy(ypdb->dom_domain, dom, sizeof ypdb->dom_domain);
768 		ypdb->dom_lockfd = -1;
769 		ypdb->dom_pnext = ypbindlist;
770 		ypbindlist = ypdb;
771 	}
772 
773 	/* soft update, alive */
774 	if(ypdb->dom_alive==1 && force==0) {
775 		if (bcmp((char *)raddrp, (char *)&ypdb->dom_server_addr,
776 			 sizeof ypdb->dom_server_addr) == 0) {
777 			ypdb->dom_alive = 1;
778 			ypdb->dom_check_t = time(NULL) + 60; /* recheck binding in 60 sec */
779 		}
780 		return;
781 	}
782 
783 	bcopy((char *)raddrp, (char *)&ypdb->dom_server_addr,
784 		sizeof ypdb->dom_server_addr);
785 	ypdb->dom_check_t = time(NULL) + 60;	/* recheck binding in 60 seconds */
786 	ypdb->dom_vers = YPVERS;
787 	ypdb->dom_alive = 1;
788 
789 	if(ypdb->dom_lockfd != -1)
790 		close(ypdb->dom_lockfd);
791 
792 	sprintf(path, "%s/%s.%d", BINDINGDIR,
793 		ypdb->dom_domain, ypdb->dom_vers);
794 #ifdef O_SHLOCK
795 	if( (fd=open(path, O_CREAT|O_SHLOCK|O_RDWR|O_TRUNC, 0644)) == -1) {
796 		(void)mkdir(BINDINGDIR, 0755);
797 		if( (fd=open(path, O_CREAT|O_SHLOCK|O_RDWR|O_TRUNC, 0644)) == -1)
798 			return;
799 	}
800 #else
801 	if( (fd=open(path, O_CREAT|O_RDWR|O_TRUNC, 0644)) == -1) {
802 		(void)mkdir(BINDINGDIR, 0755);
803 		if( (fd=open(path, O_CREAT|O_RDWR|O_TRUNC, 0644)) == -1)
804 			return;
805 	}
806 	flock(fd, LOCK_SH);
807 #endif
808 
809 	/*
810 	 * ok, if BINDINGDIR exists, and we can create the binding file,
811 	 * then write to it..
812 	 */
813 	ypdb->dom_lockfd = fd;
814 
815 	iov[0].iov_base = (caddr_t)&(udptransp->xp_port);
816 	iov[0].iov_len = sizeof udptransp->xp_port;
817 	iov[1].iov_base = (caddr_t)&ybr;
818 	iov[1].iov_len = sizeof ybr;
819 
820 	bzero(&ybr, sizeof ybr);
821 	ybr.ypbind_status = YPBIND_SUCC_VAL;
822 	ybr.ypbind_respbody.ypbind_bindinfo.ypbind_binding_addr = raddrp->sin_addr;
823 	ybr.ypbind_respbody.ypbind_bindinfo.ypbind_binding_port = raddrp->sin_port;
824 
825 	if( writev(ypdb->dom_lockfd, iov, 2) != iov[0].iov_len + iov[1].iov_len) {
826 		perror("write");
827 		close(ypdb->dom_lockfd);
828 		unlink(path);
829 		ypdb->dom_lockfd = -1;
830 		return;
831 	}
832 }
833