xref: /netbsd-src/usr.sbin/rbootd/rmpproto.c (revision daf6c4152fcddc27c445489775ed1f66ab4ea9a9)
1 /*	$NetBSD: rmpproto.c,v 1.15 2011/02/08 20:20:28 rmind Exp $	*/
2 
3 /*
4  * Copyright (c) 1988, 1992 The University of Utah and the Center
5  *	for Software Science (CSS).
6  * Copyright (c) 1992, 1993
7  *	The Regents of the University of California.  All rights reserved.
8  *
9  * This code is derived from software contributed to Berkeley by
10  * the Center for Software Science of the University of Utah Computer
11  * Science Department.  CSS requests users of this software to return
12  * to css-dist@cs.utah.edu any improvements that they make and grant
13  * CSS redistribution rights.
14  *
15  * Redistribution and use in source and binary forms, with or without
16  * modification, are permitted provided that the following conditions
17  * are met:
18  * 1. Redistributions of source code must retain the above copyright
19  *    notice, this list of conditions and the following disclaimer.
20  * 2. Redistributions in binary form must reproduce the above copyright
21  *    notice, this list of conditions and the following disclaimer in the
22  *    documentation and/or other materials provided with the distribution.
23  * 3. Neither the name of the University nor the names of its contributors
24  *    may be used to endorse or promote products derived from this software
25  *    without specific prior written permission.
26  *
27  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
28  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
29  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
30  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
31  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
32  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
33  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
34  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
35  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
36  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
37  * SUCH DAMAGE.
38  *
39  *	from: @(#)rmpproto.c	8.1 (Berkeley) 6/4/93
40  *
41  * From: Utah Hdr: rmpproto.c 3.1 92/07/06
42  * Author: Jeff Forys, University of Utah CSS
43  */
44 
45 #include <sys/cdefs.h>
46 #ifndef lint
47 #if 0
48 static char sccsid[] = "@(#)rmpproto.c	8.1 (Berkeley) 6/4/93";
49 #else
50 __RCSID("$NetBSD: rmpproto.c,v 1.15 2011/02/08 20:20:28 rmind Exp $");
51 #endif
52 #endif /* not lint */
53 
54 #include <sys/param.h>
55 #include <sys/time.h>
56 
57 #include <errno.h>
58 #include <fcntl.h>
59 #include <stdio.h>
60 #include <string.h>
61 #include <syslog.h>
62 #include <unistd.h>
63 #include "defs.h"
64 
65 /*
66 **  ProcessPacket -- determine packet type and do what's required.
67 **
68 **	An RMP BOOT packet has been received.  Look at the type field
69 **	and process Boot Requests, Read Requests, and Boot Complete
70 **	packets.  Any other type will be dropped with a warning msg.
71 **
72 **	Parameters:
73 **		rconn - the new connection
74 **		client - list of files available to this host
75 **
76 **	Returns:
77 **		Nothing.
78 **
79 **	Side Effects:
80 **		- If this is a valid boot request, it will be added to
81 **		  the linked list of outstanding requests (RmpConns).
82 **		- If this is a valid boot complete, its associated
83 **		  entry in RmpConns will be deleted.
84 **		- Also, unless we run out of memory, a reply will be
85 **		  sent to the host that sent the packet.
86 */
87 void
88 ProcessPacket(rconn, client)
89 	RMPCONN *rconn;
90 	CLIENT *client;
91 {
92 	struct rmp_packet *rmp;
93 	RMPCONN *rconnout;
94 
95 	rmp = &rconn->rmp;		/* cache pointer to RMP packet */
96 
97 	switch(rmp->r_type) {		/* do what we came here to do */
98 		case RMP_BOOT_REQ:		/* boot request */
99 			if ((rconnout = NewConn(rconn)) == NULL)
100 				return;
101 
102 			/*
103 			 *  If the Session ID is 0xffff, this is a "probe"
104 			 *  packet and we do not want to add the connection
105 			 *  to the linked list of active connections.  There
106 			 *  are two types of probe packets, if the Sequence
107 			 *  Number is 0 they want to know our host name, o/w
108 			 *  they want the name of the file associated with
109 			 *  the number spec'd by the Sequence Number.
110 			 *
111 			 *  If this is an actual boot request, open the file
112 			 *  and send a reply.  If SendBootRepl() does not
113 			 *  return 0, add the connection to the linked list
114 			 *  of active connections, otherwise delete it since
115 			 *  an error was encountered.
116 			 */
117 			if (ntohs(rmp->r_brq.rmp_session) == RMP_PROBESID) {
118 				if (WORDZE(rmp->r_brq.rmp_seqno))
119 					(void) SendServerID(rconnout);
120 				else
121 					(void) SendFileNo(rmp, rconnout,
122 					                  client? client->files:
123 					                          BootFiles);
124 				FreeConn(rconnout);
125 			} else {
126 				if (SendBootRepl(rmp, rconnout,
127 				    client? client->files: BootFiles))
128 					AddConn(rconnout);
129 				else
130 					FreeConn(rconnout);
131 			}
132 			break;
133 
134 		case RMP_BOOT_REPL:		/* boot reply (not valid) */
135 			syslog(LOG_WARNING, "%s: sent a boot reply",
136 			       EnetStr(rconn));
137 			break;
138 
139 		case RMP_READ_REQ:		/* read request */
140 			/*
141 			 *  Send a portion of the boot file.
142 			 */
143 			(void) SendReadRepl(rconn);
144 			break;
145 
146 		case RMP_READ_REPL:		/* read reply (not valid) */
147 			syslog(LOG_WARNING, "%s: sent a read reply",
148 			       EnetStr(rconn));
149 			break;
150 
151 		case RMP_BOOT_DONE:		/* boot complete */
152 			/*
153 			 *  Remove the entry from the linked list of active
154 			 *  connections.
155 			 */
156 			(void) BootDone(rconn);
157 			break;
158 
159 		default:			/* unknown RMP packet type */
160 			syslog(LOG_WARNING, "%s: unknown packet type (%u)",
161 			       EnetStr(rconn), rmp->r_type);
162 	}
163 }
164 
165 /*
166 **  SendServerID -- send our host name to who ever requested it.
167 **
168 **	Parameters:
169 **		rconn - the reply packet to be formatted.
170 **
171 **	Returns:
172 **		1 on success, 0 on failure.
173 **
174 **	Side Effects:
175 **		none.
176 */
177 int
178 SendServerID(rconn)
179 	RMPCONN *rconn;
180 {
181 	struct rmp_packet *rpl;
182 	char *src, *dst;
183 	u_int8_t *size;
184 
185 	rpl = &rconn->rmp;			/* cache ptr to RMP packet */
186 
187 	/*
188 	 *  Set up assorted fields in reply packet.
189 	 */
190 	rpl->r_brpl.rmp_type = RMP_BOOT_REPL;
191 	rpl->r_brpl.rmp_retcode = RMP_E_OKAY;
192 	ZEROWORD(rpl->r_brpl.rmp_seqno);
193 	rpl->r_brpl.rmp_session = 0;
194 	rpl->r_brpl.rmp_version = htons(RMP_VERSION);
195 
196 	size = &rpl->r_brpl.rmp_flnmsize;	/* ptr to length of host name */
197 
198 	/*
199 	 *  Copy our host name into the reply packet incrementing the
200 	 *  length as we go.  Stop at RMP_HOSTLEN or the first dot.
201 	 */
202 	src = MyHost;
203 	dst = (char *) &rpl->r_brpl.rmp_flnm;
204 	for (*size = 0; *size < RMP_HOSTLEN; (*size)++) {
205 		if (*src == '.' || *src == '\0')
206 			break;
207 		*dst++ = *src++;
208 	}
209 
210 	rconn->rmplen = RMPBOOTSIZE(*size);	/* set packet length */
211 
212 	return(SendPacket(rconn));		/* send packet */
213 }
214 
215 /*
216 **  SendFileNo -- send the name of a bootable file to the requester.
217 **
218 **	Parameters:
219 **		req - RMP BOOT packet containing the request.
220 **		rconn - the reply packet to be formatted.
221 **		filelist - list of files available to the requester.
222 **
223 **	Returns:
224 **		1 on success, 0 on failure.
225 **
226 **	Side Effects:
227 **		none.
228 */
229 int
230 SendFileNo(req, rconn, filelist)
231 	struct rmp_packet *req;
232 	RMPCONN *rconn;
233 	char *filelist[];
234 {
235 	struct rmp_packet *rpl;
236 	char *src, *dst;
237 	u_int8_t *size;
238 	int i;
239 
240 	GETWORD(req->r_brpl.rmp_seqno, i);	/* SeqNo is really FileNo */
241 	rpl = &rconn->rmp;			/* cache ptr to RMP packet */
242 
243 	/*
244 	 *  Set up assorted fields in reply packet.
245 	 */
246 	rpl->r_brpl.rmp_type = RMP_BOOT_REPL;
247 	PUTWORD(i, rpl->r_brpl.rmp_seqno);
248 	i--;
249 	rpl->r_brpl.rmp_session = 0;
250 	rpl->r_brpl.rmp_version = htons(RMP_VERSION);
251 
252 	size = &rpl->r_brpl.rmp_flnmsize;	/* ptr to length of filename */
253 	*size = 0;				/* init length to zero */
254 
255 	/*
256 	 *  Copy the file name into the reply packet incrementing the
257 	 *  length as we go.  Stop at end of string or when RMPBOOTDATA
258 	 *  characters have been copied.  Also, set return code to
259 	 *  indicate success or "no more files".
260 	 */
261 	if (i < C_MAXFILE && filelist[i] != NULL) {
262 		src = filelist[i];
263 		dst = (char *)&rpl->r_brpl.rmp_flnm;
264 		for (; *src && *size < RMPBOOTDATA; (*size)++) {
265 			if (*src == '\0')
266 				break;
267 			*dst++ = *src++;
268 		}
269 		rpl->r_brpl.rmp_retcode = RMP_E_OKAY;
270 	} else
271 		rpl->r_brpl.rmp_retcode = RMP_E_NODFLT;
272 
273 	rconn->rmplen = RMPBOOTSIZE(*size);	/* set packet length */
274 
275 	return(SendPacket(rconn));		/* send packet */
276 }
277 
278 /*
279 **  SendBootRepl -- open boot file and respond to boot request.
280 **
281 **	Parameters:
282 **		req - RMP BOOT packet containing the request.
283 **		rconn - the reply packet to be formatted.
284 **		filelist - list of files available to the requester.
285 **
286 **	Returns:
287 **		1 on success, 0 on failure.
288 **
289 **	Side Effects:
290 **		none.
291 */
292 int
293 SendBootRepl(req, rconn, filelist)
294 	struct rmp_packet *req;
295 	RMPCONN *rconn;
296 	char *filelist[];
297 {
298 	int retval;
299 	char *filename, filepath[RMPBOOTDATA+1];
300 	RMPCONN *oldconn;
301 	struct rmp_packet *rpl;
302 	char *src, *dst1, *dst2;
303 	u_int8_t i;
304 
305 	/*
306 	 *  If another connection already exists, delete it since we
307 	 *  are obviously starting again.
308 	 */
309 	if ((oldconn = FindConn(rconn)) != NULL) {
310 		syslog(LOG_WARNING, "%s: dropping existing connection",
311 		       EnetStr(oldconn));
312 		RemoveConn(oldconn);
313 	}
314 
315 	rpl = &rconn->rmp;			/* cache ptr to RMP packet */
316 
317 	/*
318 	 *  Set up assorted fields in reply packet.
319 	 */
320 	rpl->r_brpl.rmp_type = RMP_BOOT_REPL;
321 	COPYWORD(req->r_brq.rmp_seqno, rpl->r_brpl.rmp_seqno);
322 	rpl->r_brpl.rmp_session = htons(GenSessID());
323 	rpl->r_brpl.rmp_version = htons(RMP_VERSION);
324 	rpl->r_brpl.rmp_flnmsize = req->r_brq.rmp_flnmsize;
325 
326 	/*
327 	 *  Copy file name to `filepath' string, and into reply packet.
328 	 */
329 	dst1 = filepath;
330 	dst2 = &rpl->r_brpl.rmp_flnm;
331 	if (req->r_brq.rmp_flnmsize)
332 		src = &req->r_brq.rmp_flnm;
333 	else {
334 		/* no file supplied, substitute the first one */
335 		src = filelist[0];
336 		req->r_brq.rmp_flnmsize = strlen(src);
337 	}
338 	for (i = 0; i < req->r_brq.rmp_flnmsize; i++)
339 		*dst1++ = *dst2++ = *src++;
340 	*dst1 = '\0';
341 
342 	/*
343 	 *  If we are booting HP-UX machines, their secondary loader will
344 	 *  ask for files like "/hp-ux".  As a security measure, we do not
345 	 *  allow boot files to lay outside the boot directory (unless they
346 	 *  are purposely link'd out.  So, make `filename' become the path-
347 	 *  stripped file name and spoof the client into thinking that it
348 	 *  really got what it wanted.
349 	 */
350 	if ((filename = strrchr(filepath,'/')) != NULL)
351 		filename++;
352 	else
353 		filename = filepath;
354 
355 	/*
356 	 *  Check that this is a valid boot file name.
357 	 */
358 	for (i = 0; i < C_MAXFILE && filelist[i] != NULL; i++)
359 		if (STREQN(filename, filelist[i]))
360 			goto match;
361 
362 	/*
363 	 *  Invalid boot file name, set error and send reply packet.
364 	 */
365 	rpl->r_brpl.rmp_retcode = RMP_E_NOFILE;
366 	retval = 0;
367 	goto sendpkt;
368 
369 match:
370 	/*
371 	 *  This is a valid boot file.  Open the file and save the file
372 	 *  descriptor associated with this connection and set success
373 	 *  indication.  If the file couldnt be opened, set error:
374 	 *  	"no such file or dir" - RMP_E_NOFILE
375 	 *	"file table overflow" - RMP_E_BUSY
376 	 *	"too many open files" - RMP_E_BUSY
377 	 *	anything else         - RMP_E_OPENFILE
378 	 */
379 	if ((rconn->bootfd = open(filename, O_RDONLY, 0600)) < 0) {
380 		rpl->r_brpl.rmp_retcode = (errno == ENOENT)? RMP_E_NOFILE:
381 			(errno == EMFILE || errno == ENFILE)? RMP_E_BUSY:
382 			RMP_E_OPENFILE;
383 		retval = 0;
384 	} else {
385 		rpl->r_brpl.rmp_retcode = RMP_E_OKAY;
386 		retval = 1;
387 	}
388 
389 sendpkt:
390 	syslog(LOG_INFO, "%s: request to boot %s (%s)",
391 	       EnetStr(rconn), filename, retval? "granted": "denied");
392 
393 	rconn->rmplen = RMPBOOTSIZE(rpl->r_brpl.rmp_flnmsize);
394 
395 	return (retval & SendPacket(rconn));
396 }
397 
398 /*
399 **  SendReadRepl -- send a portion of the boot file to the requester.
400 **
401 **	Parameters:
402 **		rconn - the reply packet to be formatted.
403 **
404 **	Returns:
405 **		1 on success, 0 on failure.
406 **
407 **	Side Effects:
408 **		none.
409 */
410 int
411 SendReadRepl(rconn)
412 	RMPCONN *rconn;
413 {
414 	int retval = 0;
415 	RMPCONN *oldconn;
416 	struct rmp_packet *rpl, *req;
417 	int size = 0;
418 	int madeconn = 0;
419 
420 	/*
421 	 *  Find the old connection.  If one doesnt exist, create one only
422 	 *  to return the error code.
423 	 */
424 	if ((oldconn = FindConn(rconn)) == NULL) {
425 		if ((oldconn = NewConn(rconn)) == NULL)
426 			return(0);
427 		syslog(LOG_ERR, "SendReadRepl: no active connection (%s)",
428 		       EnetStr(rconn));
429 		madeconn++;
430 	}
431 
432 	req = &rconn->rmp;		/* cache ptr to request packet */
433 	rpl = &oldconn->rmp;		/* cache ptr to reply packet */
434 
435 	if (madeconn) {			/* no active connection above; abort */
436 		rpl->r_rrpl.rmp_retcode = RMP_E_ABORT;
437 		retval = 1;
438 		goto sendpkt;
439 	}
440 
441 	/*
442 	 *  Make sure Session ID's match.
443 	 */
444 	if (ntohs(req->r_rrq.rmp_session) !=
445 	    ((rpl->r_type == RMP_BOOT_REPL)? ntohs(rpl->r_brpl.rmp_session):
446 	                                     ntohs(rpl->r_rrpl.rmp_session))) {
447 		syslog(LOG_ERR, "SendReadRepl: bad session id (%s)",
448 		       EnetStr(rconn));
449 		rpl->r_rrpl.rmp_retcode = RMP_E_BADSID;
450 		retval = 1;
451 		goto sendpkt;
452 	}
453 
454 	/*
455 	 *  If the requester asks for more data than we can fit,
456 	 *  silently clamp the request size down to RMPREADDATA.
457 	 *
458 	 *  N.B. I do not know if this is "legal", however it seems
459 	 *  to work.  This is necessary for bpfwrite() on machines
460 	 *  with MCLBYTES less than 1514.
461 	 */
462 	if (ntohs(req->r_rrq.rmp_size) > RMPREADDATA)
463 		req->r_rrq.rmp_size = htons(RMPREADDATA);
464 
465 	/*
466 	 *  Position read head on file according to info in request packet.
467 	 */
468 	GETWORD(req->r_rrq.rmp_offset, size);
469 	if (lseek(oldconn->bootfd, (off_t)size, SEEK_SET) < 0) {
470 		syslog(LOG_ERR, "SendReadRepl: lseek: %m (%s)",
471 		       EnetStr(rconn));
472 		rpl->r_rrpl.rmp_retcode = RMP_E_ABORT;
473 		retval = 1;
474 		goto sendpkt;
475 	}
476 
477 	/*
478 	 *  Read data directly into reply packet.
479 	 */
480 	if ((size = read(oldconn->bootfd, &rpl->r_rrpl.rmp_data,
481 	                 (int) ntohs(req->r_rrq.rmp_size))) <= 0) {
482 		if (size < 0) {
483 			syslog(LOG_ERR, "SendReadRepl: read: %m (%s)",
484 			       EnetStr(rconn));
485 			rpl->r_rrpl.rmp_retcode = RMP_E_ABORT;
486 		} else {
487 			rpl->r_rrpl.rmp_retcode = RMP_E_EOF;
488 		}
489 		retval = 1;
490 		goto sendpkt;
491 	}
492 
493 	/*
494 	 *  Set success indication.
495 	 */
496 	rpl->r_rrpl.rmp_retcode = RMP_E_OKAY;
497 
498 sendpkt:
499 	/*
500 	 *  Set up assorted fields in reply packet.
501 	 */
502 	rpl->r_rrpl.rmp_type = RMP_READ_REPL;
503 	COPYWORD(req->r_rrq.rmp_offset, rpl->r_rrpl.rmp_offset);
504 	rpl->r_rrpl.rmp_session = req->r_rrq.rmp_session;
505 
506 	oldconn->rmplen = RMPREADSIZE(size);	/* set size of packet */
507 
508 	retval &= SendPacket(oldconn);		/* send packet */
509 
510 	if (madeconn)				/* clean up after ourself */
511 		FreeConn(oldconn);
512 
513 	return (retval);
514 }
515 
516 /*
517 **  BootDone -- free up memory allocated for a connection.
518 **
519 **	Parameters:
520 **		rconn - incoming boot complete packet.
521 **
522 **	Returns:
523 **		1 on success, 0 on failure.
524 **
525 **	Side Effects:
526 **		none.
527 */
528 int
529 BootDone(rconn)
530 	RMPCONN *rconn;
531 {
532 	RMPCONN *oldconn;
533 	struct rmp_packet *rpl;
534 
535 	/*
536 	 *  If we cant find the connection, ignore the request.
537 	 */
538 	if ((oldconn = FindConn(rconn)) == NULL) {
539 		syslog(LOG_ERR, "BootDone: no existing connection (%s)",
540 		       EnetStr(rconn));
541 		return(0);
542 	}
543 
544 	rpl = &oldconn->rmp;			/* cache ptr to RMP packet */
545 
546 	/*
547 	 *  Make sure Session ID's match.
548 	 */
549 	if (ntohs(rconn->rmp.r_rrq.rmp_session) !=
550 	    ((rpl->r_type == RMP_BOOT_REPL)? ntohs(rpl->r_brpl.rmp_session):
551 	                                    ntohs(rpl->r_rrpl.rmp_session))) {
552 		syslog(LOG_ERR, "BootDone: bad session id (%s)",
553 		       EnetStr(rconn));
554 		return(0);
555 	}
556 
557 	RemoveConn(oldconn);			/* remove connection */
558 
559 	syslog(LOG_INFO, "%s: boot complete", EnetStr(rconn));
560 
561 	return(1);
562 }
563 
564 /*
565 **  SendPacket -- send an RMP packet to a remote host.
566 **
567 **	Parameters:
568 **		rconn - packet to be sent.
569 **
570 **	Returns:
571 **		1 on success, 0 on failure.
572 **
573 **	Side Effects:
574 **		none.
575 */
576 int
577 SendPacket(rconn)
578 	RMPCONN *rconn;
579 {
580 	/*
581 	 *  Set Ethernet Destination address to Source (BPF and the enet
582 	 *  driver will take care of getting our source address set).
583 	 */
584 	memmove((char *)&rconn->rmp.hp_hdr.daddr[0],
585 	    (char *)&rconn->rmp.hp_hdr.saddr[0], RMP_ADDRLEN);
586 	rconn->rmp.hp_hdr.len = htons(rconn->rmplen - sizeof(struct hp_hdr));
587 
588 	/*
589 	 *  Reverse 802.2/HP Extended Source & Destination Access Pts.
590 	 */
591 	rconn->rmp.hp_llc.dxsap = htons(HPEXT_SXSAP);
592 	rconn->rmp.hp_llc.sxsap = htons(HPEXT_DXSAP);
593 
594 	/*
595 	 *  Last time this connection was active.
596 	 */
597 	(void) gettimeofday(&rconn->tstamp, (struct timezone *)0);
598 
599 	if (DbgFp != NULL)			/* display packet */
600 		DispPkt(rconn,DIR_SENT);
601 
602 	/*
603 	 *  Send RMP packet to remote host.
604 	 */
605 	return(BpfWrite(rconn));
606 }
607