xref: /netbsd-src/usr.sbin/rbootd/rmpproto.c (revision 481fca6e59249d8ffcf24fef7cfbe7b131bfb080)
1 /*	$NetBSD: rmpproto.c,v 1.11 1999/02/01 17:00:44 bouyer 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. All advertising materials mentioning features or use of this software
24  *    must display the following acknowledgement:
25  *	This product includes software developed by the University of
26  *	California, Berkeley and its contributors.
27  * 4. Neither the name of the University nor the names of its contributors
28  *    may be used to endorse or promote products derived from this software
29  *    without specific prior written permission.
30  *
31  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
32  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
33  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
34  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
35  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
39  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
40  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
41  * SUCH DAMAGE.
42  *
43  *	from: @(#)rmpproto.c	8.1 (Berkeley) 6/4/93
44  *
45  * From: Utah Hdr: rmpproto.c 3.1 92/07/06
46  * Author: Jeff Forys, University of Utah CSS
47  */
48 
49 #include <sys/cdefs.h>
50 #ifndef lint
51 #if 0
52 static char sccsid[] = "@(#)rmpproto.c	8.1 (Berkeley) 6/4/93";
53 #else
54 __RCSID("$NetBSD: rmpproto.c,v 1.11 1999/02/01 17:00:44 bouyer Exp $");
55 #endif
56 #endif /* not lint */
57 
58 #include <sys/param.h>
59 #include <sys/time.h>
60 
61 #include <errno.h>
62 #include <fcntl.h>
63 #include <stdio.h>
64 #include <string.h>
65 #include <syslog.h>
66 #include <unistd.h>
67 #include "defs.h"
68 
69 /*
70 **  ProcessPacket -- determine packet type and do what's required.
71 **
72 **	An RMP BOOT packet has been received.  Look at the type field
73 **	and process Boot Requests, Read Requests, and Boot Complete
74 **	packets.  Any other type will be dropped with a warning msg.
75 **
76 **	Parameters:
77 **		rconn - the new connection
78 **		client - list of files available to this host
79 **
80 **	Returns:
81 **		Nothing.
82 **
83 **	Side Effects:
84 **		- If this is a valid boot request, it will be added to
85 **		  the linked list of outstanding requests (RmpConns).
86 **		- If this is a valid boot complete, its associated
87 **		  entry in RmpConns will be deleted.
88 **		- Also, unless we run out of memory, a reply will be
89 **		  sent to the host that sent the packet.
90 */
91 void
92 ProcessPacket(rconn, client)
93 	RMPCONN *rconn;
94 	CLIENT *client;
95 {
96 	struct rmp_packet *rmp;
97 	RMPCONN *rconnout;
98 
99 	rmp = &rconn->rmp;		/* cache pointer to RMP packet */
100 
101 	switch(rmp->r_type) {		/* do what we came here to do */
102 		case RMP_BOOT_REQ:		/* boot request */
103 			if ((rconnout = NewConn(rconn)) == NULL)
104 				return;
105 
106 			/*
107 			 *  If the Session ID is 0xffff, this is a "probe"
108 			 *  packet and we do not want to add the connection
109 			 *  to the linked list of active connections.  There
110 			 *  are two types of probe packets, if the Sequence
111 			 *  Number is 0 they want to know our host name, o/w
112 			 *  they want the name of the file associated with
113 			 *  the number spec'd by the Sequence Number.
114 			 *
115 			 *  If this is an actual boot request, open the file
116 			 *  and send a reply.  If SendBootRepl() does not
117 			 *  return 0, add the connection to the linked list
118 			 *  of active connections, otherwise delete it since
119 			 *  an error was encountered.
120 			 */
121 			if (ntohs(rmp->r_brq.rmp_session) == RMP_PROBESID) {
122 				if (WORDZE(rmp->r_brq.rmp_seqno))
123 					(void) SendServerID(rconnout);
124 				else
125 					(void) SendFileNo(rmp, rconnout,
126 					                  client? client->files:
127 					                          BootFiles);
128 				FreeConn(rconnout);
129 			} else {
130 				if (SendBootRepl(rmp, rconnout,
131 				    client? client->files: BootFiles))
132 					AddConn(rconnout);
133 				else
134 					FreeConn(rconnout);
135 			}
136 			break;
137 
138 		case RMP_BOOT_REPL:		/* boot reply (not valid) */
139 			syslog(LOG_WARNING, "%s: sent a boot reply",
140 			       EnetStr(rconn));
141 			break;
142 
143 		case RMP_READ_REQ:		/* read request */
144 			/*
145 			 *  Send a portion of the boot file.
146 			 */
147 			(void) SendReadRepl(rconn);
148 			break;
149 
150 		case RMP_READ_REPL:		/* read reply (not valid) */
151 			syslog(LOG_WARNING, "%s: sent a read reply",
152 			       EnetStr(rconn));
153 			break;
154 
155 		case RMP_BOOT_DONE:		/* boot complete */
156 			/*
157 			 *  Remove the entry from the linked list of active
158 			 *  connections.
159 			 */
160 			(void) BootDone(rconn);
161 			break;
162 
163 		default:			/* unknown RMP packet type */
164 			syslog(LOG_WARNING, "%s: unknown packet type (%u)",
165 			       EnetStr(rconn), rmp->r_type);
166 	}
167 }
168 
169 /*
170 **  SendServerID -- send our host name to who ever requested it.
171 **
172 **	Parameters:
173 **		rconn - the reply packet to be formatted.
174 **
175 **	Returns:
176 **		1 on success, 0 on failure.
177 **
178 **	Side Effects:
179 **		none.
180 */
181 int
182 SendServerID(rconn)
183 	RMPCONN *rconn;
184 {
185 	struct rmp_packet *rpl;
186 	char *src, *dst;
187 	u_int8_t *size;
188 
189 	rpl = &rconn->rmp;			/* cache ptr to RMP packet */
190 
191 	/*
192 	 *  Set up assorted fields in reply packet.
193 	 */
194 	rpl->r_brpl.rmp_type = RMP_BOOT_REPL;
195 	rpl->r_brpl.rmp_retcode = RMP_E_OKAY;
196 	ZEROWORD(rpl->r_brpl.rmp_seqno);
197 	rpl->r_brpl.rmp_session = 0;
198 	rpl->r_brpl.rmp_version = htons(RMP_VERSION);
199 
200 	size = &rpl->r_brpl.rmp_flnmsize;	/* ptr to length of host name */
201 
202 	/*
203 	 *  Copy our host name into the reply packet incrementing the
204 	 *  length as we go.  Stop at RMP_HOSTLEN or the first dot.
205 	 */
206 	src = MyHost;
207 	dst = (char *) &rpl->r_brpl.rmp_flnm;
208 	for (*size = 0; *size < RMP_HOSTLEN; (*size)++) {
209 		if (*src == '.' || *src == '\0')
210 			break;
211 		*dst++ = *src++;
212 	}
213 
214 	rconn->rmplen = RMPBOOTSIZE(*size);	/* set packet length */
215 
216 	return(SendPacket(rconn));		/* send packet */
217 }
218 
219 /*
220 **  SendFileNo -- send the name of a bootable file to the requester.
221 **
222 **	Parameters:
223 **		req - RMP BOOT packet containing the request.
224 **		rconn - the reply packet to be formatted.
225 **		filelist - list of files available to the requester.
226 **
227 **	Returns:
228 **		1 on success, 0 on failure.
229 **
230 **	Side Effects:
231 **		none.
232 */
233 int
234 SendFileNo(req, rconn, filelist)
235 	struct rmp_packet *req;
236 	RMPCONN *rconn;
237 	char *filelist[];
238 {
239 	struct rmp_packet *rpl;
240 	char *src, *dst;
241 	u_int8_t *size;
242 	int i;
243 
244 	GETWORD(req->r_brpl.rmp_seqno, i);	/* SeqNo is really FileNo */
245 	rpl = &rconn->rmp;			/* cache ptr to RMP packet */
246 
247 	/*
248 	 *  Set up assorted fields in reply packet.
249 	 */
250 	rpl->r_brpl.rmp_type = RMP_BOOT_REPL;
251 	PUTWORD(i, rpl->r_brpl.rmp_seqno);
252 	i--;
253 	rpl->r_brpl.rmp_session = 0;
254 	rpl->r_brpl.rmp_version = htons(RMP_VERSION);
255 
256 	size = &rpl->r_brpl.rmp_flnmsize;	/* ptr to length of filename */
257 	*size = 0;				/* init length to zero */
258 
259 	/*
260 	 *  Copy the file name into the reply packet incrementing the
261 	 *  length as we go.  Stop at end of string or when RMPBOOTDATA
262 	 *  characters have been copied.  Also, set return code to
263 	 *  indicate success or "no more files".
264 	 */
265 	if (i < C_MAXFILE && filelist[i] != NULL) {
266 		src = filelist[i];
267 		dst = (char *)&rpl->r_brpl.rmp_flnm;
268 		for (; *src && *size < RMPBOOTDATA; (*size)++) {
269 			if (*src == '\0')
270 				break;
271 			*dst++ = *src++;
272 		}
273 		rpl->r_brpl.rmp_retcode = RMP_E_OKAY;
274 	} else
275 		rpl->r_brpl.rmp_retcode = RMP_E_NODFLT;
276 
277 	rconn->rmplen = RMPBOOTSIZE(*size);	/* set packet length */
278 
279 	return(SendPacket(rconn));		/* send packet */
280 }
281 
282 /*
283 **  SendBootRepl -- open boot file and respond to boot request.
284 **
285 **	Parameters:
286 **		req - RMP BOOT packet containing the request.
287 **		rconn - the reply packet to be formatted.
288 **		filelist - list of files available to the requester.
289 **
290 **	Returns:
291 **		1 on success, 0 on failure.
292 **
293 **	Side Effects:
294 **		none.
295 */
296 int
297 SendBootRepl(req, rconn, filelist)
298 	struct rmp_packet *req;
299 	RMPCONN *rconn;
300 	char *filelist[];
301 {
302 	int retval;
303 	char *filename, filepath[RMPBOOTDATA+1];
304 	RMPCONN *oldconn;
305 	struct rmp_packet *rpl;
306 	char *src, *dst1, *dst2;
307 	u_int8_t i;
308 
309 	/*
310 	 *  If another connection already exists, delete it since we
311 	 *  are obviously starting again.
312 	 */
313 	if ((oldconn = FindConn(rconn)) != NULL) {
314 		syslog(LOG_WARNING, "%s: dropping existing connection",
315 		       EnetStr(oldconn));
316 		RemoveConn(oldconn);
317 	}
318 
319 	rpl = &rconn->rmp;			/* cache ptr to RMP packet */
320 
321 	/*
322 	 *  Set up assorted fields in reply packet.
323 	 */
324 	rpl->r_brpl.rmp_type = RMP_BOOT_REPL;
325 	COPYWORD(req->r_brq.rmp_seqno, rpl->r_brpl.rmp_seqno);
326 	rpl->r_brpl.rmp_session = htons(GenSessID());
327 	rpl->r_brpl.rmp_version = htons(RMP_VERSION);
328 	rpl->r_brpl.rmp_flnmsize = req->r_brq.rmp_flnmsize;
329 
330 	/*
331 	 *  Copy file name to `filepath' string, and into reply packet.
332 	 */
333 	dst1 = filepath;
334 	dst2 = &rpl->r_brpl.rmp_flnm;
335 	if (req->r_brq.rmp_flnmsize)
336 		src = &req->r_brq.rmp_flnm;
337 	else {
338 		/* no file supplied, substitute the first one */
339 		src = filelist[0];
340 		req->r_brq.rmp_flnmsize = strlen(src);
341 	}
342 	for (i = 0; i < req->r_brq.rmp_flnmsize; i++)
343 		*dst1++ = *dst2++ = *src++;
344 	*dst1 = '\0';
345 
346 	/*
347 	 *  If we are booting HP-UX machines, their secondary loader will
348 	 *  ask for files like "/hp-ux".  As a security measure, we do not
349 	 *  allow boot files to lay outside the boot directory (unless they
350 	 *  are purposely link'd out.  So, make `filename' become the path-
351 	 *  stripped file name and spoof the client into thinking that it
352 	 *  really got what it wanted.
353 	 */
354 	filename = (filename = strrchr(filepath,'/'))? ++filename: filepath;
355 
356 	/*
357 	 *  Check that this is a valid boot file name.
358 	 */
359 	for (i = 0; i < C_MAXFILE && filelist[i] != NULL; i++)
360 		if (STREQN(filename, filelist[i]))
361 			goto match;
362 
363 	/*
364 	 *  Invalid boot file name, set error and send reply packet.
365 	 */
366 	rpl->r_brpl.rmp_retcode = RMP_E_NOFILE;
367 	retval = 0;
368 	goto sendpkt;
369 
370 match:
371 	/*
372 	 *  This is a valid boot file.  Open the file and save the file
373 	 *  descriptor associated with this connection and set success
374 	 *  indication.  If the file couldnt be opened, set error:
375 	 *  	"no such file or dir" - RMP_E_NOFILE
376 	 *	"file table overflow" - RMP_E_BUSY
377 	 *	"too many open files" - RMP_E_BUSY
378 	 *	anything else         - RMP_E_OPENFILE
379 	 */
380 	if ((rconn->bootfd = open(filename, O_RDONLY, 0600)) < 0) {
381 		rpl->r_brpl.rmp_retcode = (errno == ENOENT)? RMP_E_NOFILE:
382 			(errno == EMFILE || errno == ENFILE)? RMP_E_BUSY:
383 			RMP_E_OPENFILE;
384 		retval = 0;
385 	} else {
386 		rpl->r_brpl.rmp_retcode = RMP_E_OKAY;
387 		retval = 1;
388 	}
389 
390 sendpkt:
391 	syslog(LOG_INFO, "%s: request to boot %s (%s)",
392 	       EnetStr(rconn), filename, retval? "granted": "denied");
393 
394 	rconn->rmplen = RMPBOOTSIZE(rpl->r_brpl.rmp_flnmsize);
395 
396 	return (retval & SendPacket(rconn));
397 }
398 
399 /*
400 **  SendReadRepl -- send a portion of the boot file to the requester.
401 **
402 **	Parameters:
403 **		rconn - the reply packet to be formatted.
404 **
405 **	Returns:
406 **		1 on success, 0 on failure.
407 **
408 **	Side Effects:
409 **		none.
410 */
411 int
412 SendReadRepl(rconn)
413 	RMPCONN *rconn;
414 {
415 	int retval = 0;
416 	RMPCONN *oldconn;
417 	struct rmp_packet *rpl, *req;
418 	int size = 0;
419 	int madeconn = 0;
420 
421 	/*
422 	 *  Find the old connection.  If one doesnt exist, create one only
423 	 *  to return the error code.
424 	 */
425 	if ((oldconn = FindConn(rconn)) == NULL) {
426 		if ((oldconn = NewConn(rconn)) == NULL)
427 			return(0);
428 		syslog(LOG_ERR, "SendReadRepl: no active connection (%s)",
429 		       EnetStr(rconn));
430 		madeconn++;
431 	}
432 
433 	req = &rconn->rmp;		/* cache ptr to request packet */
434 	rpl = &oldconn->rmp;		/* cache ptr to reply packet */
435 
436 	if (madeconn) {			/* no active connection above; abort */
437 		rpl->r_rrpl.rmp_retcode = RMP_E_ABORT;
438 		retval = 1;
439 		goto sendpkt;
440 	}
441 
442 	/*
443 	 *  Make sure Session ID's match.
444 	 */
445 	if (ntohs(req->r_rrq.rmp_session) !=
446 	    ((rpl->r_type == RMP_BOOT_REPL)? ntohs(rpl->r_brpl.rmp_session):
447 	                                     ntohs(rpl->r_rrpl.rmp_session))) {
448 		syslog(LOG_ERR, "SendReadRepl: bad session id (%s)",
449 		       EnetStr(rconn));
450 		rpl->r_rrpl.rmp_retcode = RMP_E_BADSID;
451 		retval = 1;
452 		goto sendpkt;
453 	}
454 
455 	/*
456 	 *  If the requester asks for more data than we can fit,
457 	 *  silently clamp the request size down to RMPREADDATA.
458 	 *
459 	 *  N.B. I do not know if this is "legal", however it seems
460 	 *  to work.  This is necessary for bpfwrite() on machines
461 	 *  with MCLBYTES less than 1514.
462 	 */
463 	if (ntohs(req->r_rrq.rmp_size) > RMPREADDATA)
464 		req->r_rrq.rmp_size = htons(RMPREADDATA);
465 
466 	/*
467 	 *  Position read head on file according to info in request packet.
468 	 */
469 	GETWORD(req->r_rrq.rmp_offset, size);
470 	if (lseek(oldconn->bootfd, (off_t)size, SEEK_SET) < 0) {
471 		syslog(LOG_ERR, "SendReadRepl: lseek: %m (%s)",
472 		       EnetStr(rconn));
473 		rpl->r_rrpl.rmp_retcode = RMP_E_ABORT;
474 		retval = 1;
475 		goto sendpkt;
476 	}
477 
478 	/*
479 	 *  Read data directly into reply packet.
480 	 */
481 	if ((size = read(oldconn->bootfd, &rpl->r_rrpl.rmp_data,
482 	                 (int) ntohs(req->r_rrq.rmp_size))) <= 0) {
483 		if (size < 0) {
484 			syslog(LOG_ERR, "SendReadRepl: read: %m (%s)",
485 			       EnetStr(rconn));
486 			rpl->r_rrpl.rmp_retcode = RMP_E_ABORT;
487 		} else {
488 			rpl->r_rrpl.rmp_retcode = RMP_E_EOF;
489 		}
490 		retval = 1;
491 		goto sendpkt;
492 	}
493 
494 	/*
495 	 *  Set success indication.
496 	 */
497 	rpl->r_rrpl.rmp_retcode = RMP_E_OKAY;
498 
499 sendpkt:
500 	/*
501 	 *  Set up assorted fields in reply packet.
502 	 */
503 	rpl->r_rrpl.rmp_type = RMP_READ_REPL;
504 	COPYWORD(req->r_rrq.rmp_offset, rpl->r_rrpl.rmp_offset);
505 	rpl->r_rrpl.rmp_session = req->r_rrq.rmp_session;
506 
507 	oldconn->rmplen = RMPREADSIZE(size);	/* set size of packet */
508 
509 	retval &= SendPacket(oldconn);		/* send packet */
510 
511 	if (madeconn)				/* clean up after ourself */
512 		FreeConn(oldconn);
513 
514 	return (retval);
515 }
516 
517 /*
518 **  BootDone -- free up memory allocated for a connection.
519 **
520 **	Parameters:
521 **		rconn - incoming boot complete packet.
522 **
523 **	Returns:
524 **		1 on success, 0 on failure.
525 **
526 **	Side Effects:
527 **		none.
528 */
529 int
530 BootDone(rconn)
531 	RMPCONN *rconn;
532 {
533 	RMPCONN *oldconn;
534 	struct rmp_packet *rpl;
535 
536 	/*
537 	 *  If we cant find the connection, ignore the request.
538 	 */
539 	if ((oldconn = FindConn(rconn)) == NULL) {
540 		syslog(LOG_ERR, "BootDone: no existing connection (%s)",
541 		       EnetStr(rconn));
542 		return(0);
543 	}
544 
545 	rpl = &oldconn->rmp;			/* cache ptr to RMP packet */
546 
547 	/*
548 	 *  Make sure Session ID's match.
549 	 */
550 	if (ntohs(rconn->rmp.r_rrq.rmp_session) !=
551 	    ((rpl->r_type == RMP_BOOT_REPL)? ntohs(rpl->r_brpl.rmp_session):
552 	                                    ntohs(rpl->r_rrpl.rmp_session))) {
553 		syslog(LOG_ERR, "BootDone: bad session id (%s)",
554 		       EnetStr(rconn));
555 		return(0);
556 	}
557 
558 	RemoveConn(oldconn);			/* remove connection */
559 
560 	syslog(LOG_INFO, "%s: boot complete", EnetStr(rconn));
561 
562 	return(1);
563 }
564 
565 /*
566 **  SendPacket -- send an RMP packet to a remote host.
567 **
568 **	Parameters:
569 **		rconn - packet to be sent.
570 **
571 **	Returns:
572 **		1 on success, 0 on failure.
573 **
574 **	Side Effects:
575 **		none.
576 */
577 int
578 SendPacket(rconn)
579 	RMPCONN *rconn;
580 {
581 	/*
582 	 *  Set Ethernet Destination address to Source (BPF and the enet
583 	 *  driver will take care of getting our source address set).
584 	 */
585 	memmove((char *)&rconn->rmp.hp_hdr.daddr[0],
586 	    (char *)&rconn->rmp.hp_hdr.saddr[0], RMP_ADDRLEN);
587 #ifdef __FreeBSD__
588 	/* BPF (incorrectly) wants this in host order. */
589 	rconn->rmp.hp_hdr.len = rconn->rmplen - sizeof(struct hp_hdr);
590 #else
591 	rconn->rmp.hp_hdr.len = htons(rconn->rmplen - sizeof(struct hp_hdr));
592 #endif
593 
594 	/*
595 	 *  Reverse 802.2/HP Extended Source & Destination Access Pts.
596 	 */
597 	rconn->rmp.hp_llc.dxsap = htons(HPEXT_SXSAP);
598 	rconn->rmp.hp_llc.sxsap = htons(HPEXT_DXSAP);
599 
600 	/*
601 	 *  Last time this connection was active.
602 	 */
603 	(void) gettimeofday(&rconn->tstamp, (struct timezone *)0);
604 
605 	if (DbgFp != NULL)			/* display packet */
606 		DispPkt(rconn,DIR_SENT);
607 
608 	/*
609 	 *  Send RMP packet to remote host.
610 	 */
611 	return(BpfWrite(rconn));
612 }
613