1 /*	$NetBSD: bootparamd.c,v 1.48 2020/04/22 23:47:02 joerg Exp $	*/
2 
3 /*
4  * This code is not copyright, and is placed in the public domain.
5  * Feel free to use and modify. Please send modifications and/or
6  * suggestions + bug fixes to Klas Heggemann <klas@nada.kth.se>
7  *
8  * Various small changes by Theo de Raadt <deraadt@fsa.ca>
9  * Parser rewritten (adding YP support) by Roland McGrath <roland@frob.com>
10  */
11 
12 #include <sys/cdefs.h>
13 #ifndef lint
14 __RCSID("$NetBSD: bootparamd.c,v 1.48 2020/04/22 23:47:02 joerg Exp $");
15 #endif
16 
17 #include <sys/types.h>
18 #include <sys/ioctl.h>
19 #include <sys/stat.h>
20 #include <sys/socket.h>
21 
22 #include <assert.h>
23 #include <ctype.h>
24 #include <errno.h>
25 #include <err.h>
26 #include <fnmatch.h>
27 #include <netdb.h>
28 #include <stdlib.h>
29 #include <stdio.h>
30 #include <string.h>
31 #include <syslog.h>
32 #include <unistd.h>
33 #include <util.h>
34 #include <ifaddrs.h>
35 
36 #include <net/if.h>
37 
38 #include <netinet/in.h>
39 #include <arpa/inet.h>
40 
41 #include <rpc/rpc.h>
42 #include <rpc/pmap_clnt.h>
43 #include <rpcsvc/bootparam_prot.h>
44 #ifdef YP
45 #include <rpcsvc/ypclnt.h>
46 #endif
47 
48 #include "pathnames.h"
49 
50 #define MAXLEN 800
51 
52 static char hostname[MAX_MACHINE_NAME];
53 static char askname[MAX_MACHINE_NAME];
54 static char domain_name[MAX_MACHINE_NAME];
55 
56 extern void bootparamprog_1(struct svc_req *, SVCXPRT *);
57 
58 extern int	_rpcsvcdirty;
59 extern int	_rpcpmstart;
60 int     debug = 0;
61 int     dolog = 0;
62 struct in_addr route_addr;
63 struct sockaddr_in my_addr;
64 const char *bootpfile = _PATH_BOOTPARAMS;
65 char   *iface = NULL;
66 
67 static int	lookup_bootparam(char *, char *, char *, char **, char **);
68 __dead static void	usage(void);
69 static int get_localaddr(const char *, struct sockaddr_in *);
70 
71 
72 /*
73  * ever familiar
74  */
75 int
main(int argc,char * argv[])76 main(int argc, char  *argv[])
77 {
78 	SVCXPRT *transp;
79 	struct hostent *he;
80 	struct stat buf;
81 	int    c;
82 
83 	while ((c = getopt(argc, argv, "di:sr:f:")) != -1)
84 		switch (c) {
85 		case 'd':
86 			debug = 1;
87 			break;
88 		case 'i':
89 			iface = optarg;
90 			break;
91 		case 'r':
92 			if (isdigit((unsigned char)*optarg)) {
93 				if (inet_aton(optarg, &route_addr) != 0)
94 					break;
95 			}
96 			he = gethostbyname(optarg);
97 			if (he == 0) {
98 				warnx("no such host: %s", optarg);
99 				usage();
100 			}
101 			memmove(&route_addr.s_addr, he->h_addr, he->h_length);
102 			break;
103 		case 'f':
104 			bootpfile = optarg;
105 			break;
106 		case 's':
107 			dolog = 1;
108 #ifndef LOG_DAEMON
109 			openlog("rpc.bootparamd", 0, 0);
110 #else
111 			openlog("rpc.bootparamd", 0, LOG_DAEMON);
112 			setlogmask(LOG_UPTO(LOG_NOTICE));
113 #endif
114 			break;
115 		default:
116 			usage();
117 		}
118 
119 	if (stat(bootpfile, &buf))
120 		err(1, "%s", bootpfile);
121 
122 	if (route_addr.s_addr == 0) {
123 		if (get_localaddr(NULL, &my_addr) != 0)
124 			errx(1, "router address not found");
125 		route_addr.s_addr = my_addr.sin_addr.s_addr;
126 	}
127 	if (!debug) {
128 		if (daemon(0, 0))
129 			err(1, "can't detach from terminal");
130 	}
131 	pidfile(NULL);
132 
133 	(void) pmap_unset(BOOTPARAMPROG, BOOTPARAMVERS);
134 
135 	transp = svcudp_create(RPC_ANYSOCK);
136 	if (transp == NULL)
137 		errx(1, "can't create udp service");
138 
139 	if (!svc_register(transp, BOOTPARAMPROG, BOOTPARAMVERS, bootparamprog_1,
140 	    IPPROTO_UDP))
141 /*
142  * Do NOT change the "%u" in the format string below to "%lu". If your
143  * build fails update the "rpcgen" program and use "make cleandir" and
144  * "make includes" in "src/lib/librpcsvc" afterwards.
145  */
146 		errx(1, "unable to register BOOTPARAMPROG version %u, udp",
147 		    BOOTPARAMVERS);
148 
149 	svc_run();
150 	errx(1, "svc_run returned");
151 }
152 
153 bp_whoami_res *
bootparamproc_whoami_1_svc(bp_whoami_arg * whoami,struct svc_req * rqstp)154 bootparamproc_whoami_1_svc(bp_whoami_arg *whoami, struct svc_req *rqstp)
155 {
156 	static bp_whoami_res res;
157 	struct hostent *he;
158 	struct in_addr haddr;
159 	int e;
160 
161 	if (debug)
162 		warnx("whoami got question for %d.%d.%d.%d",
163 		    255 & whoami->client_address.bp_address_u.ip_addr.net,
164 		    255 & whoami->client_address.bp_address_u.ip_addr.host,
165 		    255 & whoami->client_address.bp_address_u.ip_addr.lh,
166 		    255 & whoami->client_address.bp_address_u.ip_addr.impno);
167 	if (dolog)
168 		syslog(LOG_NOTICE, "whoami got question for %d.%d.%d.%d",
169 		    255 & whoami->client_address.bp_address_u.ip_addr.net,
170 		    255 & whoami->client_address.bp_address_u.ip_addr.host,
171 		    255 & whoami->client_address.bp_address_u.ip_addr.lh,
172 		    255 & whoami->client_address.bp_address_u.ip_addr.impno);
173 
174 	memmove((char *) &haddr,
175 	    (char *) &whoami->client_address.bp_address_u.ip_addr,
176 	    sizeof(haddr));
177 	he = gethostbyaddr((char *) &haddr, sizeof(haddr), AF_INET);
178 	if (he) {
179 		(void)strlcpy(askname, he->h_name, sizeof(askname));
180 	} else {
181 		(void)strlcpy(askname, inet_ntoa(haddr), sizeof(askname));
182 	}
183 
184 	if (debug)
185 		warnx("This is host %s", askname);
186 	if (dolog)
187 		syslog(LOG_NOTICE, "This is host %s", askname);
188 
189 	if ((e = lookup_bootparam(askname, hostname, NULL, NULL, NULL)) == 0) {
190 		res.client_name = hostname;
191 		getdomainname(domain_name, MAX_MACHINE_NAME);
192 		res.domain_name = domain_name;
193 
194 		if (res.router_address.address_type != IP_ADDR_TYPE) {
195 			res.router_address.address_type = IP_ADDR_TYPE;
196 			memmove(&res.router_address.bp_address_u.ip_addr,
197 			    &route_addr.s_addr,4);
198 		}
199 		if (debug)
200 			warnx("Returning %s   %s    %d.%d.%d.%d",
201 			    res.client_name, res.domain_name,
202 			    255 & res.router_address.bp_address_u.ip_addr.net,
203 			    255 & res.router_address.bp_address_u.ip_addr.host,
204 			    255 & res.router_address.bp_address_u.ip_addr.lh,
205 			    255 &res.router_address.bp_address_u.ip_addr.impno);
206 		if (dolog)
207 			syslog(LOG_NOTICE, "Returning %s   %s    %d.%d.%d.%d",
208 			    res.client_name, res.domain_name,
209 			    255 & res.router_address.bp_address_u.ip_addr.net,
210 			    255 & res.router_address.bp_address_u.ip_addr.host,
211 			    255 & res.router_address.bp_address_u.ip_addr.lh,
212 			    255 &res.router_address.bp_address_u.ip_addr.impno);
213 
214 		return (&res);
215 	}
216 	errno = e;
217 	if (debug)
218 		warn("whoami failed");
219 	if (dolog)
220 		syslog(LOG_NOTICE, "whoami failed %m");
221 	return (NULL);
222 }
223 
224 
225 bp_getfile_res *
bootparamproc_getfile_1_svc(bp_getfile_arg * getfile,struct svc_req * rqstp)226 bootparamproc_getfile_1_svc(bp_getfile_arg *getfile, struct svc_req *rqstp)
227 {
228 	static bp_getfile_res res;
229 	struct hostent *he;
230 	int     error;
231 
232 	if (debug)
233 		warnx("getfile got question for \"%s\" and file \"%s\"",
234 		    getfile->client_name, getfile->file_id);
235 
236 	if (dolog)
237 		syslog(LOG_NOTICE,
238 		    "getfile got question for \"%s\" and file \"%s\"",
239 		    getfile->client_name, getfile->file_id);
240 
241 	he = NULL;
242 	he = gethostbyname(getfile->client_name);
243 	if (!he) {
244 		if (debug)
245 			warnx("getfile can't resolve client %s",
246 			    getfile->client_name);
247 		if (dolog)
248 			syslog(LOG_NOTICE, "getfile can't resolve client %s",
249 			    getfile->client_name);
250 		return (NULL);
251 	}
252 
253 	(void)strlcpy(askname, he->h_name, sizeof(askname));
254 	error = lookup_bootparam(askname, NULL, getfile->file_id,
255 	    &res.server_name, &res.server_path);
256 	if (error == 0) {
257 		he = gethostbyname(res.server_name);
258 		if (!he) {
259 			if (debug)
260 				warnx("getfile can't resolve server %s for %s",
261 			    res.server_name, getfile->client_name);
262 		if (dolog)
263 			syslog(LOG_NOTICE,
264 			    "getfile can't resolve server %s for %s",
265 			    res.server_name, getfile->client_name);
266 		return (NULL);
267 
268 		}
269 		memmove(&res.server_address.bp_address_u.ip_addr,
270 		    he->h_addr, 4);
271 		res.server_address.address_type = IP_ADDR_TYPE;
272 	} else if (error == ENOENT && !strcmp(getfile->file_id, "dump")) {
273 		/* Special for dump, answer with null strings. */
274 		res.server_name[0] = '\0';
275 		res.server_path[0] = '\0';
276 		memset(&res.server_address.bp_address_u.ip_addr, 0, 4);
277 	} else {
278 		if (debug)
279 			warnx("getfile lookup failed for %s",
280 			    getfile->client_name);
281 		if (dolog)
282 			syslog(LOG_NOTICE,
283 			    "getfile lookup failed for %s",
284 			    getfile->client_name);
285 		return (NULL);
286 	}
287 
288 	if (debug)
289 		warnx(
290 		    "returning server:%s path:%s address: %d.%d.%d.%d",
291 		    res.server_name, res.server_path,
292 		    255 & res.server_address.bp_address_u.ip_addr.net,
293 		    255 & res.server_address.bp_address_u.ip_addr.host,
294 		    255 & res.server_address.bp_address_u.ip_addr.lh,
295 		    255 & res.server_address.bp_address_u.ip_addr.impno);
296 	if (dolog)
297 		syslog(LOG_NOTICE,
298 		    "returning server:%s path:%s address: %d.%d.%d.%d",
299 		    res.server_name, res.server_path,
300 		    255 & res.server_address.bp_address_u.ip_addr.net,
301 		    255 & res.server_address.bp_address_u.ip_addr.host,
302 		    255 & res.server_address.bp_address_u.ip_addr.lh,
303 		    255 & res.server_address.bp_address_u.ip_addr.impno);
304 	return (&res);
305 }
306 
307 
308 static int
lookup_bootparam(char * client,char * client_canonical,char * id,char ** server,char ** path)309 lookup_bootparam(char *client, char *client_canonical, char *id,
310     char **server, char **path)
311 {
312 	FILE   *f = fopen(bootpfile, "r");
313 #ifdef YP
314 	static char *ypbuf = NULL;
315 	static int ypbuflen = 0;
316 #endif
317 	static char buf[BUFSIZ];
318 	char   *canon = NULL, *bp, *word = NULL;
319 	size_t  idlen = id == NULL ? 0 : strlen(id);
320 	int     contin = 0;
321 	int     found = 0;
322 
323 	if (f == NULL)
324 		return EINVAL;	/* ? */
325 
326 	while (fgets(buf, sizeof buf, f)) {
327 		int     wascontin = contin;
328 		contin = buf[strlen(buf) - 2] == '\\';
329 		bp = buf + strspn(buf, " \t\n");
330 
331 		switch (wascontin) {
332 		case -1:
333 			/* Continuation of uninteresting line */
334 			contin *= -1;
335 			continue;
336 		case 0:
337 			/* New line */
338 			contin *= -1;
339 			if (*bp == '#')
340 				continue;
341 			if ((word = strsep(&bp, " \t\n")) == NULL)
342 				continue;
343 #ifdef YP
344 			/* A + in the file means try YP now */
345 			if (!strcmp(word, "+")) {
346 				char   *ypdom;
347 
348 				if (yp_get_default_domain(&ypdom) ||
349 				    yp_match(ypdom, "bootparams", client,
350 					strlen(client), &ypbuf, &ypbuflen))
351 					continue;
352 				bp = ypbuf;
353 				word = client;
354 				contin *= -1;
355 				break;
356 			}
357 #endif
358 			if (debug)
359 				warnx("match %s with %s", word, client);
360 
361 #define	HASGLOB(str) \
362 	(strchr(str, '*') != NULL || \
363 	 strchr(str, '?') != NULL || \
364 	 strchr(str, '[') != NULL || \
365 	 strchr(str, ']') != NULL)
366 
367 			/* See if this line's client is the one we are
368 			 * looking for */
369 			if (fnmatch(word, client, FNM_CASEFOLD) == 0) {
370 				/*
371 				 * Match.  The token may be globbed, we
372 				 * can't just return that as the canonical
373 				 * name.  Check to see if the token has any
374 				 * globbing characters in it (*, ?, [, ]).
375 				 * If so, just return the name we already
376 				 * have.  Otherwise, return the token.
377 				 */
378 				if (HASGLOB(word))
379 					canon = client;
380 				else
381 					canon = word;
382 			} else {
383 				struct hostent *hp;
384 				/*
385 				 * If it didn't match, try getting the
386 				 * canonical host name of the client
387 				 * on this line, if it's not a glob,
388 				 * and comparing it to the client we
389 				 * are looking up.
390 				 */
391 				if (HASGLOB(word)) {
392 					if (debug)
393 						warnx("Skipping non-match: %s",
394 						    word);
395 					continue;
396 				}
397 				if ((hp = gethostbyname(word)) == NULL) {
398 					if (debug)
399 						warnx(
400 					    "Unknown bootparams host %s",
401 					    word);
402 					if (dolog)
403 						syslog(LOG_NOTICE,
404 					    "Unknown bootparams host %s",
405 					    word);
406 					continue;
407 				}
408 				if (strcasecmp(hp->h_name, client) != 0)
409 					continue;
410 				canon = hp->h_name;
411 			}
412 
413 #undef HASGLOB
414 
415 			contin *= -1;
416 			break;
417 		case 1:
418 			/* Continued line we want to parse below */
419 			break;
420 		}
421 
422 		assert(canon != NULL);
423 		if (client_canonical)
424 			strncpy(client_canonical, canon, MAX_MACHINE_NAME);
425 
426 		/* We have found a line for CLIENT */
427 		if (id == NULL) {
428 			(void) fclose(f);
429 			return 0;
430 		}
431 
432 		/* Look for a value for the parameter named by ID */
433 		while ((word = strsep(&bp, " \t\n")) != NULL) {
434 			if (!strncmp(word, id, idlen) && word[idlen] == '=') {
435 				/* We have found the entry we want */
436 				*server = &word[idlen + 1];
437 				*path = strchr(*server, ':');
438 				if (*path == NULL)
439 					/* Malformed entry */
440 					continue;
441 				*(*path)++ = '\0';
442 				(void) fclose(f);
443 				return 0;
444 			}
445 		}
446 
447 		found = 1;
448 	}
449 
450 	(void) fclose(f);
451 	return found ? ENOENT : EPERM;
452 }
453 
454 static void
usage(void)455 usage(void)
456 {
457 	fprintf(stderr,
458 	    "usage: %s [-ds] [-i interface] [-r router] [-f bootparamsfile]\n",
459 	    getprogname());
460 	exit(1);
461 }
462 
463 static int
get_localaddr(const char * ifname,struct sockaddr_in * sin)464 get_localaddr(const char *ifname, struct sockaddr_in *sin)
465 {
466 	struct ifaddrs *ifap, *ifa;
467 
468 	if (getifaddrs(&ifap) != 0)
469 		return -1;
470 
471 	for (ifa = ifap; ifa; ifa = ifa->ifa_next) {
472 		if (ifname && strcmp(ifname, ifa->ifa_name) != 0)
473 			continue;
474 		if (ifa->ifa_addr->sa_family != AF_INET)
475 			continue;
476 		if (ifa->ifa_addr->sa_len != sizeof(*sin))
477 			continue;
478 
479 		/* no loopback please */
480 #ifdef IFF_LOOPBACK
481 		if (ifa->ifa_flags & IFF_LOOPBACK)
482 			continue;
483 #else
484 		if (strncmp(ifa->ifa_name, "lo", 2) == 0 &&
485 		    (isdigit(ifa->ifa_name[2]) || ifa->ifa_name[2] == '\0'))
486 			continue;
487 #endif
488 
489 		if (!iface || strcmp(ifa->ifa_name, iface) == 0)
490 			;
491 		else
492 			continue;
493 
494 		/* candidate found */
495 		memcpy(sin, ifa->ifa_addr, ifa->ifa_addr->sa_len);
496 		freeifaddrs(ifap);
497 		return 0;
498 	}
499 
500 	/* no candidate */
501 	freeifaddrs(ifap);
502 	return -1;
503 }
504