xref: /netbsd-src/usr.sbin/rbootd/rmpproto.c (revision ae9172d6cd9432a6a1a56760d86b32c57a66c39c)
1 /*
2  * Copyright (c) 1988, 1992 The University of Utah and the Center
3  *	for Software Science (CSS).
4  * Copyright (c) 1992, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * This code is derived from software contributed to Berkeley by
8  * the Center for Software Science of the University of Utah Computer
9  * Science Department.  CSS requests users of this software to return
10  * to css-dist@cs.utah.edu any improvements that they make and grant
11  * CSS redistribution rights.
12  *
13  * Redistribution and use in source and binary forms, with or without
14  * modification, are permitted provided that the following conditions
15  * are met:
16  * 1. Redistributions of source code must retain the above copyright
17  *    notice, this list of conditions and the following disclaimer.
18  * 2. Redistributions in binary form must reproduce the above copyright
19  *    notice, this list of conditions and the following disclaimer in the
20  *    documentation and/or other materials provided with the distribution.
21  * 3. All advertising materials mentioning features or use of this software
22  *    must display the following acknowledgement:
23  *	This product includes software developed by the University of
24  *	California, Berkeley and its contributors.
25  * 4. Neither the name of the University nor the names of its contributors
26  *    may be used to endorse or promote products derived from this software
27  *    without specific prior written permission.
28  *
29  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
30  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
31  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
32  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
33  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
34  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
35  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
36  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
37  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
38  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
39  * SUCH DAMAGE.
40  *
41  *	from: @(#)rmpproto.c	8.1 (Berkeley) 6/4/93
42  *	      $Id: rmpproto.c,v 1.2 1994/01/11 16:41:55 brezak Exp $
43  *
44  * From: Utah Hdr: rmpproto.c 3.1 92/07/06
45  * Author: Jeff Forys, University of Utah CSS
46  */
47 
48 #ifndef lint
49 /*static char sccsid[] = "@(#)rmpproto.c	8.1 (Berkeley) 6/4/93";*/
50 static char rcsid[] = "$Id: rmpproto.c,v 1.2 1994/01/11 16:41:55 brezak Exp $";
51 #endif /* not lint */
52 
53 #include <sys/param.h>
54 #include <sys/time.h>
55 
56 #include <errno.h>
57 #include <fcntl.h>
58 #include <stdio.h>
59 #include <string.h>
60 #include <syslog.h>
61 #include <unistd.h>
62 #include "defs.h"
63 
64 /*
65 **  ProcessPacket -- determine packet type and do what's required.
66 **
67 **	An RMP BOOT packet has been received.  Look at the type field
68 **	and process Boot Requests, Read Requests, and Boot Complete
69 **	packets.  Any other type will be dropped with a warning msg.
70 **
71 **	Parameters:
72 **		rconn - the new connection
73 **		client - list of files available to this host
74 **
75 **	Returns:
76 **		Nothing.
77 **
78 **	Side Effects:
79 **		- If this is a valid boot request, it will be added to
80 **		  the linked list of outstanding requests (RmpConns).
81 **		- If this is a valid boot complete, its associated
82 **		  entry in RmpConns will be deleted.
83 **		- Also, unless we run out of memory, a reply will be
84 **		  sent to the host that sent the packet.
85 */
86 void
87 ProcessPacket(rconn, client)
88 	RMPCONN *rconn;
89 	CLIENT *client;
90 {
91 	struct rmp_packet *rmp;
92 	RMPCONN *rconnout;
93 
94 	rmp = &rconn->rmp;		/* cache pointer to RMP packet */
95 
96 	switch(rmp->r_type) {		/* do what we came here to do */
97 		case RMP_BOOT_REQ:		/* boot request */
98 			if ((rconnout = NewConn(rconn)) == NULL)
99 				return;
100 
101 			/*
102 			 *  If the Session ID is 0xffff, this is a "probe"
103 			 *  packet and we do not want to add the connection
104 			 *  to the linked list of active connections.  There
105 			 *  are two types of probe packets, if the Sequence
106 			 *  Number is 0 they want to know our host name, o/w
107 			 *  they want the name of the file associated with
108 			 *  the number spec'd by the Sequence Number.
109 			 *
110 			 *  If this is an actual boot request, open the file
111 			 *  and send a reply.  If SendBootRepl() does not
112 			 *  return 0, add the connection to the linked list
113 			 *  of active connections, otherwise delete it since
114 			 *  an error was encountered.
115 			 */
116 			if (ntohs(rmp->r_brq.rmp_session) == RMP_PROBESID) {
117 				if (WORDZE(rmp->r_brq.rmp_seqno))
118 					(void) SendServerID(rconnout);
119 				else
120 					(void) SendFileNo(rmp, rconnout,
121 					                  client? client->files:
122 					                          BootFiles);
123 				FreeConn(rconnout);
124 			} else {
125 				if (SendBootRepl(rmp, rconnout,
126 				    client? client->files: BootFiles))
127 					AddConn(rconnout);
128 				else
129 					FreeConn(rconnout);
130 			}
131 			break;
132 
133 		case RMP_BOOT_REPL:		/* boot reply (not valid) */
134 			syslog(LOG_WARNING, "%s: sent a boot reply",
135 			       EnetStr(rconn));
136 			break;
137 
138 		case RMP_READ_REQ:		/* read request */
139 			/*
140 			 *  Send a portion of the boot file.
141 			 */
142 			(void) SendReadRepl(rconn);
143 			break;
144 
145 		case RMP_READ_REPL:		/* read reply (not valid) */
146 			syslog(LOG_WARNING, "%s: sent a read reply",
147 			       EnetStr(rconn));
148 			break;
149 
150 		case RMP_BOOT_DONE:		/* boot complete */
151 			/*
152 			 *  Remove the entry from the linked list of active
153 			 *  connections.
154 			 */
155 			(void) BootDone(rconn);
156 			break;
157 
158 		default:			/* unknown RMP packet type */
159 			syslog(LOG_WARNING, "%s: unknown packet type (%u)",
160 			       EnetStr(rconn), rmp->r_type);
161 	}
162 }
163 
164 /*
165 **  SendServerID -- send our host name to who ever requested it.
166 **
167 **	Parameters:
168 **		rconn - the reply packet to be formatted.
169 **
170 **	Returns:
171 **		1 on success, 0 on failure.
172 **
173 **	Side Effects:
174 **		none.
175 */
176 int
177 SendServerID(rconn)
178 	RMPCONN *rconn;
179 {
180 	register struct rmp_packet *rpl;
181 	register char *src, *dst;
182 	register u_char *size;
183 
184 	rpl = &rconn->rmp;			/* cache ptr to RMP packet */
185 
186 	/*
187 	 *  Set up assorted fields in reply packet.
188 	 */
189 	rpl->r_brpl.rmp_type = RMP_BOOT_REPL;
190 	rpl->r_brpl.rmp_retcode = RMP_E_OKAY;
191 	ZEROWORD(rpl->r_brpl.rmp_seqno);
192 	rpl->r_brpl.rmp_session = 0;
193 	rpl->r_brpl.rmp_version = htons(RMP_VERSION);
194 
195 	size = &rpl->r_brpl.rmp_flnmsize;	/* ptr to length of host name */
196 
197 	/*
198 	 *  Copy our host name into the reply packet incrementing the
199 	 *  length as we go.  Stop at RMP_HOSTLEN or the first dot.
200 	 */
201 	src = MyHost;
202 	dst = (char *) &rpl->r_brpl.rmp_flnm;
203 	for (*size = 0; *size < RMP_HOSTLEN; (*size)++) {
204 		if (*src == '.' || *src == '\0')
205 			break;
206 		*dst++ = *src++;
207 	}
208 
209 	rconn->rmplen = RMPBOOTSIZE(*size);	/* set packet length */
210 
211 	return(SendPacket(rconn));		/* send packet */
212 }
213 
214 /*
215 **  SendFileNo -- send the name of a bootable file to the requester.
216 **
217 **	Parameters:
218 **		req - RMP BOOT packet containing the request.
219 **		rconn - the reply packet to be formatted.
220 **		filelist - list of files available to the requester.
221 **
222 **	Returns:
223 **		1 on success, 0 on failure.
224 **
225 **	Side Effects:
226 **		none.
227 */
228 int
229 SendFileNo(req, rconn, filelist)
230 	struct rmp_packet *req;
231 	RMPCONN *rconn;
232 	char *filelist[];
233 {
234 	register struct rmp_packet *rpl;
235 	register char *src, *dst;
236 	register u_char *size, i;
237 
238 	GETWORD(req->r_brpl.rmp_seqno, i);	/* SeqNo is really FileNo */
239 	rpl = &rconn->rmp;			/* cache ptr to RMP packet */
240 
241 	/*
242 	 *  Set up assorted fields in reply packet.
243 	 */
244 	rpl->r_brpl.rmp_type = RMP_BOOT_REPL;
245 	PUTWORD(i, rpl->r_brpl.rmp_seqno);
246 	i--;
247 	rpl->r_brpl.rmp_session = 0;
248 	rpl->r_brpl.rmp_version = htons(RMP_VERSION);
249 
250 	size = &rpl->r_brpl.rmp_flnmsize;	/* ptr to length of filename */
251 	*size = 0;				/* init length to zero */
252 
253 	/*
254 	 *  Copy the file name into the reply packet incrementing the
255 	 *  length as we go.  Stop at end of string or when RMPBOOTDATA
256 	 *  characters have been copied.  Also, set return code to
257 	 *  indicate success or "no more files".
258 	 */
259 	if (i < C_MAXFILE && filelist[i] != NULL) {
260 		src = filelist[i];
261 		dst = (char *)&rpl->r_brpl.rmp_flnm;
262 		for (; *src && *size < RMPBOOTDATA; (*size)++) {
263 			if (*src == '\0')
264 				break;
265 			*dst++ = *src++;
266 		}
267 		rpl->r_brpl.rmp_retcode = RMP_E_OKAY;
268 	} else
269 		rpl->r_brpl.rmp_retcode = RMP_E_NODFLT;
270 
271 	rconn->rmplen = RMPBOOTSIZE(*size);	/* set packet length */
272 
273 	return(SendPacket(rconn));		/* send packet */
274 }
275 
276 /*
277 **  SendBootRepl -- open boot file and respond to boot request.
278 **
279 **	Parameters:
280 **		req - RMP BOOT packet containing the request.
281 **		rconn - the reply packet to be formatted.
282 **		filelist - list of files available to the requester.
283 **
284 **	Returns:
285 **		1 on success, 0 on failure.
286 **
287 **	Side Effects:
288 **		none.
289 */
290 int
291 SendBootRepl(req, rconn, filelist)
292 	struct rmp_packet *req;
293 	RMPCONN *rconn;
294 	char *filelist[];
295 {
296 	int retval;
297 	char *filename, filepath[RMPBOOTDATA+1];
298 	RMPCONN *oldconn;
299 	register struct rmp_packet *rpl;
300 	register char *src, *dst1, *dst2;
301 	register u_char i;
302 
303 	/*
304 	 *  If another connection already exists, delete it since we
305 	 *  are obviously starting again.
306 	 */
307 	if ((oldconn = FindConn(rconn)) != NULL) {
308 		syslog(LOG_WARNING, "%s: dropping existing connection",
309 		       EnetStr(oldconn));
310 		RemoveConn(oldconn);
311 	}
312 
313 	rpl = &rconn->rmp;			/* cache ptr to RMP packet */
314 
315 	/*
316 	 *  Set up assorted fields in reply packet.
317 	 */
318 	rpl->r_brpl.rmp_type = RMP_BOOT_REPL;
319 	COPYWORD(req->r_brq.rmp_seqno, rpl->r_brpl.rmp_seqno);
320 	rpl->r_brpl.rmp_session = htons(GenSessID());
321 	rpl->r_brpl.rmp_version = htons(RMP_VERSION);
322 	rpl->r_brpl.rmp_flnmsize = req->r_brq.rmp_flnmsize;
323 
324 	/*
325 	 *  Copy file name to `filepath' string, and into reply packet.
326 	 */
327 	src = &req->r_brq.rmp_flnm;
328 	dst1 = filepath;
329 	dst2 = &rpl->r_brpl.rmp_flnm;
330 	for (i = 0; i < req->r_brq.rmp_flnmsize; i++)
331 		*dst1++ = *dst2++ = *src++;
332 	*dst1 = '\0';
333 
334 	/*
335 	 *  If we are booting HP-UX machines, their secondary loader will
336 	 *  ask for files like "/hp-ux".  As a security measure, we do not
337 	 *  allow boot files to lay outside the boot directory (unless they
338 	 *  are purposely link'd out.  So, make `filename' become the path-
339 	 *  stripped file name and spoof the client into thinking that it
340 	 *  really got what it wanted.
341 	 */
342 	filename = (filename = rindex(filepath,'/'))? ++filename: filepath;
343 
344 	/*
345 	 *  Check that this is a valid boot file name.
346 	 */
347 	for (i = 0; i < C_MAXFILE && filelist[i] != NULL; i++)
348 		if (STREQN(filename, filelist[i]))
349 			goto match;
350 
351 	/*
352 	 *  Invalid boot file name, set error and send reply packet.
353 	 */
354 	rpl->r_brpl.rmp_retcode = RMP_E_NOFILE;
355 	retval = 0;
356 	goto sendpkt;
357 
358 match:
359 	/*
360 	 *  This is a valid boot file.  Open the file and save the file
361 	 *  descriptor associated with this connection and set success
362 	 *  indication.  If the file couldnt be opened, set error:
363 	 *  	"no such file or dir" - RMP_E_NOFILE
364 	 *	"file table overflow" - RMP_E_BUSY
365 	 *	"too many open files" - RMP_E_BUSY
366 	 *	anything else         - RMP_E_OPENFILE
367 	 */
368 	if ((rconn->bootfd = open(filename, O_RDONLY, 0600)) < 0) {
369 		rpl->r_brpl.rmp_retcode = (errno == ENOENT)? RMP_E_NOFILE:
370 			(errno == EMFILE || errno == ENFILE)? RMP_E_BUSY:
371 			RMP_E_OPENFILE;
372 		retval = 0;
373 	} else {
374 		rpl->r_brpl.rmp_retcode = RMP_E_OKAY;
375 		retval = 1;
376 	}
377 
378 sendpkt:
379 	syslog(LOG_INFO, "%s: request to boot %s (%s)",
380 	       EnetStr(rconn), filename, retval? "granted": "denied");
381 
382 	rconn->rmplen = RMPBOOTSIZE(rpl->r_brpl.rmp_flnmsize);
383 
384 	return (retval & SendPacket(rconn));
385 }
386 
387 /*
388 **  SendReadRepl -- send a portion of the boot file to the requester.
389 **
390 **	Parameters:
391 **		rconn - the reply packet to be formatted.
392 **
393 **	Returns:
394 **		1 on success, 0 on failure.
395 **
396 **	Side Effects:
397 **		none.
398 */
399 int
400 SendReadRepl(rconn)
401 	RMPCONN *rconn;
402 {
403 	int retval;
404 	RMPCONN *oldconn;
405 	register struct rmp_packet *rpl, *req;
406 	register int size = 0;
407 	int madeconn = 0;
408 
409 	/*
410 	 *  Find the old connection.  If one doesnt exist, create one only
411 	 *  to return the error code.
412 	 */
413 	if ((oldconn = FindConn(rconn)) == NULL) {
414 		if ((oldconn = NewConn(rconn)) == NULL)
415 			return(0);
416 		syslog(LOG_ERR, "SendReadRepl: no active connection (%s)",
417 		       EnetStr(rconn));
418 		madeconn++;
419 	}
420 
421 	req = &rconn->rmp;		/* cache ptr to request packet */
422 	rpl = &oldconn->rmp;		/* cache ptr to reply packet */
423 
424 	if (madeconn) {			/* no active connection above; abort */
425 		rpl->r_rrpl.rmp_retcode = RMP_E_ABORT;
426 		retval = 1;
427 		goto sendpkt;
428 	}
429 
430 	/*
431 	 *  Make sure Session ID's match.
432 	 */
433 	if (ntohs(req->r_rrq.rmp_session) !=
434 	    ((rpl->r_type == RMP_BOOT_REPL)? ntohs(rpl->r_brpl.rmp_session):
435 	                                     ntohs(rpl->r_rrpl.rmp_session))) {
436 		syslog(LOG_ERR, "SendReadRepl: bad session id (%s)",
437 		       EnetStr(rconn));
438 		rpl->r_rrpl.rmp_retcode = RMP_E_BADSID;
439 		retval = 1;
440 		goto sendpkt;
441 	}
442 
443 	/*
444 	 *  If the requester asks for more data than we can fit,
445 	 *  silently clamp the request size down to RMPREADDATA.
446 	 *
447 	 *  N.B. I do not know if this is "legal", however it seems
448 	 *  to work.  This is necessary for bpfwrite() on machines
449 	 *  with MCLBYTES less than 1514.
450 	 */
451 	if (ntohs(req->r_rrq.rmp_size) > RMPREADDATA)
452 		req->r_rrq.rmp_size = htons(RMPREADDATA);
453 
454 	/*
455 	 *  Position read head on file according to info in request packet.
456 	 */
457 	GETWORD(req->r_rrq.rmp_offset, size);
458 	if (lseek(oldconn->bootfd, (off_t)size, L_SET) < 0) {
459 		syslog(LOG_ERR, "SendReadRepl: lseek: %m (%s)",
460 		       EnetStr(rconn));
461 		rpl->r_rrpl.rmp_retcode = RMP_E_ABORT;
462 		retval = 1;
463 		goto sendpkt;
464 	}
465 
466 	/*
467 	 *  Read data directly into reply packet.
468 	 */
469 	if ((size = read(oldconn->bootfd, &rpl->r_rrpl.rmp_data,
470 	                 (int) req->r_rrq.rmp_size)) <= 0) {
471 		if (size < 0) {
472 			syslog(LOG_ERR, "SendReadRepl: read: %m (%s)",
473 			       EnetStr(rconn));
474 			rpl->r_rrpl.rmp_retcode = RMP_E_ABORT;
475 		} else {
476 			rpl->r_rrpl.rmp_retcode = RMP_E_EOF;
477 		}
478 		retval = 1;
479 		goto sendpkt;
480 	}
481 
482 	/*
483 	 *  Set success indication.
484 	 */
485 	rpl->r_rrpl.rmp_retcode = RMP_E_OKAY;
486 
487 sendpkt:
488 	/*
489 	 *  Set up assorted fields in reply packet.
490 	 */
491 	rpl->r_rrpl.rmp_type = RMP_READ_REPL;
492 	COPYWORD(req->r_rrq.rmp_offset, rpl->r_rrpl.rmp_offset);
493 	rpl->r_rrpl.rmp_session = req->r_rrq.rmp_session;
494 
495 	oldconn->rmplen = RMPREADSIZE(size);	/* set size of packet */
496 
497 	retval &= SendPacket(oldconn);		/* send packet */
498 
499 	if (madeconn)				/* clean up after ourself */
500 		FreeConn(oldconn);
501 
502 	return (retval);
503 }
504 
505 /*
506 **  BootDone -- free up memory allocated for a connection.
507 **
508 **	Parameters:
509 **		rconn - incoming boot complete packet.
510 **
511 **	Returns:
512 **		1 on success, 0 on failure.
513 **
514 **	Side Effects:
515 **		none.
516 */
517 int
518 BootDone(rconn)
519 	RMPCONN *rconn;
520 {
521 	RMPCONN *oldconn;
522 	struct rmp_packet *rpl;
523 
524 	/*
525 	 *  If we cant find the connection, ignore the request.
526 	 */
527 	if ((oldconn = FindConn(rconn)) == NULL) {
528 		syslog(LOG_ERR, "BootDone: no existing connection (%s)",
529 		       EnetStr(rconn));
530 		return(0);
531 	}
532 
533 	rpl = &oldconn->rmp;			/* cache ptr to RMP packet */
534 
535 	/*
536 	 *  Make sure Session ID's match.
537 	 */
538 	if (ntohs(rconn->rmp.r_rrq.rmp_session) !=
539 	    ((rpl->r_type == RMP_BOOT_REPL)? ntohs(rpl->r_brpl.rmp_session):
540 	                                    ntohs(rpl->r_rrpl.rmp_session))) {
541 		syslog(LOG_ERR, "BootDone: bad session id (%s)",
542 		       EnetStr(rconn));
543 		return(0);
544 	}
545 
546 	RemoveConn(oldconn);			/* remove connection */
547 
548 	syslog(LOG_INFO, "%s: boot complete", EnetStr(rconn));
549 
550 	return(1);
551 }
552 
553 /*
554 **  SendPacket -- send an RMP packet to a remote host.
555 **
556 **	Parameters:
557 **		rconn - packet to be sent.
558 **
559 **	Returns:
560 **		1 on success, 0 on failure.
561 **
562 **	Side Effects:
563 **		none.
564 */
565 int
566 SendPacket(rconn)
567 	register RMPCONN *rconn;
568 {
569 	/*
570 	 *  Set Ethernet Destination address to Source (BPF and the enet
571 	 *  driver will take care of getting our source address set).
572 	 */
573 	bcopy((char *)&rconn->rmp.hp_hdr.saddr[0],
574 	      (char *)&rconn->rmp.hp_hdr.daddr[0], RMP_ADDRLEN);
575 	rconn->rmp.hp_hdr.len = rconn->rmplen - sizeof(struct hp_hdr);
576 
577 	/*
578 	 *  Reverse 802.2/HP Extended Source & Destination Access Pts.
579 	 */
580 	rconn->rmp.hp_llc.dxsap = HPEXT_SXSAP;
581 	rconn->rmp.hp_llc.sxsap = HPEXT_DXSAP;
582 
583 	/*
584 	 *  Last time this connection was active.
585 	 */
586 	(void) gettimeofday(&rconn->tstamp, (struct timezone *)0);
587 
588 	if (DbgFp != NULL)			/* display packet */
589 		DispPkt(rconn,DIR_SENT);
590 
591 	/*
592 	 *  Send RMP packet to remote host.
593 	 */
594 	return(BpfWrite(rconn));
595 }
596