xref: /netbsd-src/usr.sbin/rbootd/rmpproto.c (revision 81b108b45f75f89f1e3ffad9fb6f074e771c0935)
1 /*	$NetBSD: rmpproto.c,v 1.7 1996/02/01 21:27:46 mycroft 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 #ifndef lint
50 /*static char sccsid[] = "@(#)rmpproto.c	8.1 (Berkeley) 6/4/93";*/
51 static char rcsid[] = "$NetBSD: rmpproto.c,v 1.7 1996/02/01 21:27:46 mycroft Exp $";
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 	register struct rmp_packet *rpl;
182 	register char *src, *dst;
183 	register 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 	register struct rmp_packet *rpl;
236 	register char *src, *dst;
237 	register u_int8_t *size;
238 	register 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 	register struct rmp_packet *rpl;
302 	register char *src, *dst1, *dst2;
303 	register 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 	src = &req->r_brq.rmp_flnm;
330 	dst1 = filepath;
331 	dst2 = &rpl->r_brpl.rmp_flnm;
332 	for (i = 0; i < req->r_brq.rmp_flnmsize; i++)
333 		*dst1++ = *dst2++ = *src++;
334 	*dst1 = '\0';
335 
336 	/*
337 	 *  If we are booting HP-UX machines, their secondary loader will
338 	 *  ask for files like "/hp-ux".  As a security measure, we do not
339 	 *  allow boot files to lay outside the boot directory (unless they
340 	 *  are purposely link'd out.  So, make `filename' become the path-
341 	 *  stripped file name and spoof the client into thinking that it
342 	 *  really got what it wanted.
343 	 */
344 	filename = (filename = rindex(filepath,'/'))? ++filename: filepath;
345 
346 	/*
347 	 *  Check that this is a valid boot file name.
348 	 */
349 	for (i = 0; i < C_MAXFILE && filelist[i] != NULL; i++)
350 		if (STREQN(filename, filelist[i]))
351 			goto match;
352 
353 	/*
354 	 *  Invalid boot file name, set error and send reply packet.
355 	 */
356 	rpl->r_brpl.rmp_retcode = RMP_E_NOFILE;
357 	retval = 0;
358 	goto sendpkt;
359 
360 match:
361 	/*
362 	 *  This is a valid boot file.  Open the file and save the file
363 	 *  descriptor associated with this connection and set success
364 	 *  indication.  If the file couldnt be opened, set error:
365 	 *  	"no such file or dir" - RMP_E_NOFILE
366 	 *	"file table overflow" - RMP_E_BUSY
367 	 *	"too many open files" - RMP_E_BUSY
368 	 *	anything else         - RMP_E_OPENFILE
369 	 */
370 	if ((rconn->bootfd = open(filename, O_RDONLY, 0600)) < 0) {
371 		rpl->r_brpl.rmp_retcode = (errno == ENOENT)? RMP_E_NOFILE:
372 			(errno == EMFILE || errno == ENFILE)? RMP_E_BUSY:
373 			RMP_E_OPENFILE;
374 		retval = 0;
375 	} else {
376 		rpl->r_brpl.rmp_retcode = RMP_E_OKAY;
377 		retval = 1;
378 	}
379 
380 sendpkt:
381 	syslog(LOG_INFO, "%s: request to boot %s (%s)",
382 	       EnetStr(rconn), filename, retval? "granted": "denied");
383 
384 	rconn->rmplen = RMPBOOTSIZE(rpl->r_brpl.rmp_flnmsize);
385 
386 	return (retval & SendPacket(rconn));
387 }
388 
389 /*
390 **  SendReadRepl -- send a portion of the boot file to the requester.
391 **
392 **	Parameters:
393 **		rconn - the reply packet to be formatted.
394 **
395 **	Returns:
396 **		1 on success, 0 on failure.
397 **
398 **	Side Effects:
399 **		none.
400 */
401 int
402 SendReadRepl(rconn)
403 	RMPCONN *rconn;
404 {
405 	int retval = 0;
406 	RMPCONN *oldconn;
407 	register struct rmp_packet *rpl, *req;
408 	register int size = 0;
409 	int madeconn = 0;
410 
411 	/*
412 	 *  Find the old connection.  If one doesnt exist, create one only
413 	 *  to return the error code.
414 	 */
415 	if ((oldconn = FindConn(rconn)) == NULL) {
416 		if ((oldconn = NewConn(rconn)) == NULL)
417 			return(0);
418 		syslog(LOG_ERR, "SendReadRepl: no active connection (%s)",
419 		       EnetStr(rconn));
420 		madeconn++;
421 	}
422 
423 	req = &rconn->rmp;		/* cache ptr to request packet */
424 	rpl = &oldconn->rmp;		/* cache ptr to reply packet */
425 
426 	if (madeconn) {			/* no active connection above; abort */
427 		rpl->r_rrpl.rmp_retcode = RMP_E_ABORT;
428 		retval = 1;
429 		goto sendpkt;
430 	}
431 
432 	/*
433 	 *  Make sure Session ID's match.
434 	 */
435 	if (ntohs(req->r_rrq.rmp_session) !=
436 	    ((rpl->r_type == RMP_BOOT_REPL)? ntohs(rpl->r_brpl.rmp_session):
437 	                                     ntohs(rpl->r_rrpl.rmp_session))) {
438 		syslog(LOG_ERR, "SendReadRepl: bad session id (%s)",
439 		       EnetStr(rconn));
440 		rpl->r_rrpl.rmp_retcode = RMP_E_BADSID;
441 		retval = 1;
442 		goto sendpkt;
443 	}
444 
445 	/*
446 	 *  If the requester asks for more data than we can fit,
447 	 *  silently clamp the request size down to RMPREADDATA.
448 	 *
449 	 *  N.B. I do not know if this is "legal", however it seems
450 	 *  to work.  This is necessary for bpfwrite() on machines
451 	 *  with MCLBYTES less than 1514.
452 	 */
453 	if (ntohs(req->r_rrq.rmp_size) > RMPREADDATA)
454 		req->r_rrq.rmp_size = htons(RMPREADDATA);
455 
456 	/*
457 	 *  Position read head on file according to info in request packet.
458 	 */
459 	GETWORD(req->r_rrq.rmp_offset, size);
460 	if (lseek(oldconn->bootfd, (off_t)size, L_SET) < 0) {
461 		syslog(LOG_ERR, "SendReadRepl: lseek: %m (%s)",
462 		       EnetStr(rconn));
463 		rpl->r_rrpl.rmp_retcode = RMP_E_ABORT;
464 		retval = 1;
465 		goto sendpkt;
466 	}
467 
468 	/*
469 	 *  Read data directly into reply packet.
470 	 */
471 	if ((size = read(oldconn->bootfd, &rpl->r_rrpl.rmp_data,
472 	                 (int) ntohs(req->r_rrq.rmp_size))) <= 0) {
473 		if (size < 0) {
474 			syslog(LOG_ERR, "SendReadRepl: read: %m (%s)",
475 			       EnetStr(rconn));
476 			rpl->r_rrpl.rmp_retcode = RMP_E_ABORT;
477 		} else {
478 			rpl->r_rrpl.rmp_retcode = RMP_E_EOF;
479 		}
480 		retval = 1;
481 		goto sendpkt;
482 	}
483 
484 	/*
485 	 *  Set success indication.
486 	 */
487 	rpl->r_rrpl.rmp_retcode = RMP_E_OKAY;
488 
489 sendpkt:
490 	/*
491 	 *  Set up assorted fields in reply packet.
492 	 */
493 	rpl->r_rrpl.rmp_type = RMP_READ_REPL;
494 	COPYWORD(req->r_rrq.rmp_offset, rpl->r_rrpl.rmp_offset);
495 	rpl->r_rrpl.rmp_session = req->r_rrq.rmp_session;
496 
497 	oldconn->rmplen = RMPREADSIZE(size);	/* set size of packet */
498 
499 	retval &= SendPacket(oldconn);		/* send packet */
500 
501 	if (madeconn)				/* clean up after ourself */
502 		FreeConn(oldconn);
503 
504 	return (retval);
505 }
506 
507 /*
508 **  BootDone -- free up memory allocated for a connection.
509 **
510 **	Parameters:
511 **		rconn - incoming boot complete packet.
512 **
513 **	Returns:
514 **		1 on success, 0 on failure.
515 **
516 **	Side Effects:
517 **		none.
518 */
519 int
520 BootDone(rconn)
521 	RMPCONN *rconn;
522 {
523 	RMPCONN *oldconn;
524 	struct rmp_packet *rpl;
525 
526 	/*
527 	 *  If we cant find the connection, ignore the request.
528 	 */
529 	if ((oldconn = FindConn(rconn)) == NULL) {
530 		syslog(LOG_ERR, "BootDone: no existing connection (%s)",
531 		       EnetStr(rconn));
532 		return(0);
533 	}
534 
535 	rpl = &oldconn->rmp;			/* cache ptr to RMP packet */
536 
537 	/*
538 	 *  Make sure Session ID's match.
539 	 */
540 	if (ntohs(rconn->rmp.r_rrq.rmp_session) !=
541 	    ((rpl->r_type == RMP_BOOT_REPL)? ntohs(rpl->r_brpl.rmp_session):
542 	                                    ntohs(rpl->r_rrpl.rmp_session))) {
543 		syslog(LOG_ERR, "BootDone: bad session id (%s)",
544 		       EnetStr(rconn));
545 		return(0);
546 	}
547 
548 	RemoveConn(oldconn);			/* remove connection */
549 
550 	syslog(LOG_INFO, "%s: boot complete", EnetStr(rconn));
551 
552 	return(1);
553 }
554 
555 /*
556 **  SendPacket -- send an RMP packet to a remote host.
557 **
558 **	Parameters:
559 **		rconn - packet to be sent.
560 **
561 **	Returns:
562 **		1 on success, 0 on failure.
563 **
564 **	Side Effects:
565 **		none.
566 */
567 int
568 SendPacket(rconn)
569 	register RMPCONN *rconn;
570 {
571 	/*
572 	 *  Set Ethernet Destination address to Source (BPF and the enet
573 	 *  driver will take care of getting our source address set).
574 	 */
575 	bcopy((char *)&rconn->rmp.hp_hdr.saddr[0],
576 	      (char *)&rconn->rmp.hp_hdr.daddr[0], RMP_ADDRLEN);
577 #ifdef __FreeBSD__
578 	/* BPF (incorrectly) wants this in host order. */
579 	rconn->rmp.hp_hdr.len = rconn->rmplen - sizeof(struct hp_hdr);
580 #else
581 	rconn->rmp.hp_hdr.len = htons(rconn->rmplen - sizeof(struct hp_hdr));
582 #endif
583 
584 	/*
585 	 *  Reverse 802.2/HP Extended Source & Destination Access Pts.
586 	 */
587 	rconn->rmp.hp_llc.dxsap = htons(HPEXT_SXSAP);
588 	rconn->rmp.hp_llc.sxsap = htons(HPEXT_DXSAP);
589 
590 	/*
591 	 *  Last time this connection was active.
592 	 */
593 	(void) gettimeofday(&rconn->tstamp, (struct timezone *)0);
594 
595 	if (DbgFp != NULL)			/* display packet */
596 		DispPkt(rconn,DIR_SENT);
597 
598 	/*
599 	 *  Send RMP packet to remote host.
600 	 */
601 	return(BpfWrite(rconn));
602 }
603