xref: /freebsd/contrib/tcpdump/parsenfsfh.c (revision 9b3ece1c2eb92a881cb2553271e123382bfe31c1)
1 /*
2  * Copyright (c) 1993, 1994 Jeffrey C. Mogul, Digital Equipment Corporation,
3  * Western Research Laboratory. All rights reserved.
4  * Copyright (c) 2001 Compaq Computer Corporation. All rights reserved.
5  *
6  *  Permission to use, copy, and modify this software and its
7  *  documentation is hereby granted only under the following terms and
8  *  conditions.  Both the above copyright notice and this permission
9  *  notice must appear in all copies of the software, derivative works
10  *  or modified versions, and any portions thereof, and both notices
11  *  must appear in supporting documentation.
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
20  *    the documentation and/or other materials provided with the
21  *    distribution.
22  *
23  *  THE SOFTWARE IS PROVIDED "AS IS" AND COMPAQ COMPUTER CORPORATION
24  *  DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING
25  *  ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS.   IN NO
26  *  EVENT SHALL COMPAQ COMPUTER CORPORATION BE LIABLE FOR ANY
27  *  SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
28  *  WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN
29  *  AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
30  *  OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
31  *  SOFTWARE.
32  */
33 
34 /*
35  * parsenfsfh.c - portable parser for NFS file handles
36  *			uses all sorts of heuristics
37  *
38  * Jeffrey C. Mogul
39  * Digital Equipment Corporation
40  * Western Research Laboratory
41  */
42 
43 #ifdef HAVE_CONFIG_H
44 #include "config.h"
45 #endif
46 
47 #include <netdissect-stdinc.h>
48 
49 #include <stdio.h>
50 #include <string.h>
51 
52 #include "netdissect.h"
53 #include "nfsfh.h"
54 
55 /*
56  * This routine attempts to parse a file handle (in network byte order),
57  * using heuristics to guess what kind of format it is in.  See the
58  * file "fhandle_layouts" for a detailed description of the various
59  * patterns we know about.
60  *
61  * The file handle is parsed into our internal representation of a
62  * file-system id, and an internal representation of an inode-number.
63  */
64 
65 #define	FHT_UNKNOWN	0
66 #define	FHT_AUSPEX	1
67 #define	FHT_DECOSF	2
68 #define	FHT_IRIX4	3
69 #define	FHT_IRIX5	4
70 #define	FHT_SUNOS3	5
71 #define	FHT_SUNOS4	6
72 #define	FHT_ULTRIX	7
73 #define	FHT_VMSUCX	8
74 #define	FHT_SUNOS5	9
75 #define	FHT_AIX32	10
76 #define	FHT_HPUX9	11
77 #define	FHT_BSD44	12
78 
79 #ifdef	ultrix
80 /* Nasty hack to keep the Ultrix C compiler from emitting bogus warnings */
81 #define	XFF(x)	((uint32_t)(x))
82 #else
83 #define	XFF(x)	(x)
84 #endif
85 
86 #define	make_uint32(msb,b,c,lsb)\
87 	(XFF(lsb) + (XFF(c)<<8) + (XFF(b)<<16) + (XFF(msb)<<24))
88 
89 #define	make_uint24(msb,b, lsb)\
90 	(XFF(lsb) + (XFF(b)<<8) + (XFF(msb)<<16))
91 
92 #define	make_uint16(msb,lsb)\
93 	(XFF(lsb) + (XFF(msb)<<8))
94 
95 #ifdef	__alpha
96 	/* or other 64-bit systems */
97 #define	make_uint48(msb,b,c,d,e,lsb)\
98 	((lsb) + ((e)<<8) + ((d)<<16) + ((c)<<24) + ((b)<<32) + ((msb)<<40))
99 #else
100 	/* on 32-bit systems ignore high-order bits */
101 #define	make_uint48(msb,b,c,d,e,lsb)\
102 	((lsb) + ((e)<<8) + ((d)<<16) + ((c)<<24))
103 #endif
104 
105 static int is_UCX(const unsigned char *, u_int);
106 
107 void
108 Parse_fh(register const unsigned char *fh, u_int len, my_fsid *fsidp,
109 	 uint32_t *inop,
110 	 const char **osnamep, /* if non-NULL, return OS name here */
111 	 const char **fsnamep, /* if non-NULL, return server fs name here (for VMS) */
112 	 int ourself)	/* true if file handle was generated on this host */
113 {
114 	register const unsigned char *fhp = fh;
115 	uint32_t temp;
116 	int fhtype = FHT_UNKNOWN;
117 	u_int i;
118 
119 	/*
120 	 * Require at least 16 bytes of file handle; it's variable-length
121 	 * in NFSv3.  "len" is in units of 32-bit words, not bytes.
122 	 */
123 	if (len < 16/4)
124 		fhtype = FHT_UNKNOWN;
125 	else {
126 		if (ourself) {
127 		    /* File handle generated on this host, no need for guessing */
128 #if	defined(IRIX40)
129 		    fhtype = FHT_IRIX4;
130 #endif
131 #if	defined(IRIX50)
132 		    fhtype = FHT_IRIX5;
133 #endif
134 #if	defined(IRIX51)
135 		    fhtype = FHT_IRIX5;
136 #endif
137 #if	defined(SUNOS4)
138 		    fhtype = FHT_SUNOS4;
139 #endif
140 #if	defined(SUNOS5)
141 		    fhtype = FHT_SUNOS5;
142 #endif
143 #if	defined(ultrix)
144 		    fhtype = FHT_ULTRIX;
145 #endif
146 #if	defined(__osf__)
147 		    fhtype = FHT_DECOSF;
148 #endif
149 #if	defined(__NetBSD__) || defined(__FreeBSD__) || defined(__DragonFly__) \
150      || defined(__OpenBSD__)
151 		    fhtype = FHT_BSD44;
152 #endif
153 		}
154 		/*
155 		 * This is basically a big decision tree
156 		 */
157 		else if ((fhp[0] == 0) && (fhp[1] == 0)) {
158 		    /* bytes[0,1] == (0,0); rules out Ultrix, IRIX5, SUNOS5 */
159 		    /* probably rules out HP-UX, AIX unless they allow major=0 */
160 		    if ((fhp[2] == 0) && (fhp[3] == 0)) {
161 			/* bytes[2,3] == (0,0); must be Auspex */
162 			/* XXX or could be Ultrix+MASSBUS "hp" disk? */
163 			fhtype = FHT_AUSPEX;
164 		    }
165 		    else {
166 			/*
167 			 * bytes[2,3] != (0,0); rules out Auspex, could be
168 			 * DECOSF, SUNOS4, or IRIX4
169 			 */
170 			if ((fhp[4] != 0) && (fhp[5] == 0) &&
171 				(fhp[8] == 12) && (fhp[9] == 0)) {
172 			    /* seems to be DECOSF, with minor == 0 */
173 			    fhtype = FHT_DECOSF;
174 			}
175 			else {
176 			    /* could be SUNOS4 or IRIX4 */
177 			    /* XXX the test of fhp[5] == 8 could be wrong */
178 			    if ((fhp[4] == 0) && (fhp[5] == 8) && (fhp[6] == 0) &&
179 			        (fhp[7] == 0)) {
180 				/* looks like a length, not a file system typecode */
181 				fhtype = FHT_IRIX4;
182 			    }
183 			    else {
184 				/* by elimination */
185 				fhtype = FHT_SUNOS4;
186 			    }
187 			}
188 		    }
189 		}
190 		else {
191 		    /*
192 		     * bytes[0,1] != (0,0); rules out Auspex, IRIX4, SUNOS4
193 		     * could be IRIX5, DECOSF, UCX, Ultrix, SUNOS5
194 		     * could be AIX, HP-UX
195 		     */
196 		    if ((fhp[2] == 0) && (fhp[3] == 0)) {
197 			/*
198 			 * bytes[2,3] == (0,0); rules out OSF, probably not UCX
199 			 * (unless the exported device name is just one letter!),
200 			 * could be Ultrix, IRIX5, AIX, or SUNOS5
201 			 * might be HP-UX (depends on their values for minor devs)
202 			 */
203 			if ((fhp[6] == 0) && (fhp[7] == 0)) {
204 			    fhtype = FHT_BSD44;
205 			}
206 			/*XXX we probably only need to test of these two bytes */
207 			else if ((len >= 24/4) && (fhp[21] == 0) && (fhp[23] == 0)) {
208 			    fhtype = FHT_ULTRIX;
209 			}
210 			else {
211 			    /* Could be SUNOS5/IRIX5, maybe AIX */
212 			    /* XXX no obvious difference between SUNOS5 and IRIX5 */
213 			    if (fhp[9] == 10)
214 				fhtype = FHT_SUNOS5;
215 			    /* XXX what about AIX? */
216 			}
217 		    }
218 		    else {
219 			/*
220 			 * bytes[2,3] != (0,0); rules out Ultrix, could be
221 			 * DECOSF, SUNOS5, IRIX5, AIX, HP-UX, or UCX
222 			 */
223 			if ((fhp[8] == 12) && (fhp[9] == 0)) {
224 			    fhtype = FHT_DECOSF;
225 			}
226 			else if ((fhp[8] == 0) && (fhp[9] == 10)) {
227 			    /* could be SUNOS5/IRIX5, AIX, HP-UX */
228 			    if ((fhp[7] == 0) && (fhp[6] == 0) &&
229 				(fhp[5] == 0) && (fhp[4] == 0)) {
230 				/* XXX is this always true of HP-UX? */
231 				fhtype = FHT_HPUX9;
232 			    }
233 			    else if (fhp[7] == 2) {
234 				/* This would be MNT_NFS on AIX, which is impossible */
235 				fhtype = FHT_SUNOS5;	/* or maybe IRIX5 */
236 			    }
237 			    else {
238 				/*
239 				 * XXX Could be SUNOS5/IRIX5 or AIX.  I don't
240 				 * XXX see any way to disambiguate these, so
241 				 * XXX I'm going with the more likely guess.
242 				 * XXX Sorry, Big Blue.
243 				 */
244 				fhtype = FHT_SUNOS5;	/* or maybe IRIX5 */
245 			    }
246 		        }
247 			else {
248 			    if (is_UCX(fhp, len)) {
249 				fhtype = FHT_VMSUCX;
250 			    }
251 			    else {
252 				fhtype = FHT_UNKNOWN;
253 			    }
254 			}
255 		    }
256 		}
257 	}
258 
259 	/* XXX still needs to handle SUNOS3 */
260 
261 	switch (fhtype) {
262 	case FHT_AUSPEX:
263 	    fsidp->Fsid_dev.Minor = fhp[7];
264 	    fsidp->Fsid_dev.Major = fhp[6];
265 	    fsidp->fsid_code = 0;
266 
267 	    *inop = make_uint32(fhp[12], fhp[13], fhp[14], fhp[15]);
268 
269 	    if (osnamep)
270 		*osnamep = "Auspex";
271 	    break;
272 
273 	case FHT_BSD44:
274 	    fsidp->Fsid_dev.Minor = fhp[0];
275 	    fsidp->Fsid_dev.Major = fhp[1];
276 	    fsidp->fsid_code = 0;
277 
278 	    *inop = make_uint32(fhp[15], fhp[14], fhp[13], fhp[12]);
279 
280 	    if (osnamep)
281 		*osnamep = "BSD 4.4";
282 	    break;
283 
284 	case FHT_DECOSF:
285 	    fsidp->fsid_code = make_uint32(fhp[7], fhp[6], fhp[5], fhp[4]);
286 			/* XXX could ignore 3 high-order bytes */
287 
288 	    temp = make_uint32(fhp[3], fhp[2], fhp[1], fhp[0]);
289 	    fsidp->Fsid_dev.Minor = temp & 0xFFFFF;
290 	    fsidp->Fsid_dev.Major = (temp>>20) & 0xFFF;
291 
292 	    *inop = make_uint32(fhp[15], fhp[14], fhp[13], fhp[12]);
293 	    if (osnamep)
294 		*osnamep = "OSF";
295 	    break;
296 
297 	case FHT_IRIX4:
298 	    fsidp->Fsid_dev.Minor = fhp[3];
299 	    fsidp->Fsid_dev.Major = fhp[2];
300 	    fsidp->fsid_code = 0;
301 
302 	    *inop = make_uint32(fhp[8], fhp[9], fhp[10], fhp[11]);
303 
304 	    if (osnamep)
305 		*osnamep = "IRIX4";
306 	    break;
307 
308 	case FHT_IRIX5:
309 	    fsidp->Fsid_dev.Minor = make_uint16(fhp[2], fhp[3]);
310 	    fsidp->Fsid_dev.Major = make_uint16(fhp[0], fhp[1]);
311 	    fsidp->fsid_code = make_uint32(fhp[4], fhp[5], fhp[6], fhp[7]);
312 
313 	    *inop = make_uint32(fhp[12], fhp[13], fhp[14], fhp[15]);
314 
315 	    if (osnamep)
316 		*osnamep = "IRIX5";
317 	    break;
318 
319 #ifdef notdef
320 	case FHT_SUNOS3:
321 	    /*
322 	     * XXX - none of the heuristics above return this.
323 	     * Are there any SunOS 3.x systems around to care about?
324 	     */
325 	    if (osnamep)
326 		*osnamep = "SUNOS3";
327 	    break;
328 #endif
329 
330 	case FHT_SUNOS4:
331 	    fsidp->Fsid_dev.Minor = fhp[3];
332 	    fsidp->Fsid_dev.Major = fhp[2];
333 	    fsidp->fsid_code = make_uint32(fhp[4], fhp[5], fhp[6], fhp[7]);
334 
335 	    *inop = make_uint32(fhp[12], fhp[13], fhp[14], fhp[15]);
336 
337 	    if (osnamep)
338 		*osnamep = "SUNOS4";
339 	    break;
340 
341 	case FHT_SUNOS5:
342 	    temp = make_uint16(fhp[0], fhp[1]);
343 	    fsidp->Fsid_dev.Major = (temp>>2) &  0x3FFF;
344 	    temp = make_uint24(fhp[1], fhp[2], fhp[3]);
345 	    fsidp->Fsid_dev.Minor = temp & 0x3FFFF;
346 	    fsidp->fsid_code = make_uint32(fhp[4], fhp[5], fhp[6], fhp[7]);
347 
348 	    *inop = make_uint32(fhp[12], fhp[13], fhp[14], fhp[15]);
349 
350 	    if (osnamep)
351 		*osnamep = "SUNOS5";
352 	    break;
353 
354 	case FHT_ULTRIX:
355 	    fsidp->fsid_code = 0;
356 	    fsidp->Fsid_dev.Minor = fhp[0];
357 	    fsidp->Fsid_dev.Major = fhp[1];
358 
359 	    temp = make_uint32(fhp[7], fhp[6], fhp[5], fhp[4]);
360 	    *inop = temp;
361 	    if (osnamep)
362 		*osnamep = "Ultrix";
363 	    break;
364 
365 	case FHT_VMSUCX:
366 	    /* No numeric file system ID, so hash on the device-name */
367 	    if (sizeof(*fsidp) >= 14) {
368 		if (sizeof(*fsidp) > 14)
369 		    memset((char *)fsidp, 0, sizeof(*fsidp));
370 		/* just use the whole thing */
371 		memcpy((char *)fsidp, (const char *)fh, 14);
372 	    }
373 	    else {
374 		uint32_t tempa[4];	/* at least 16 bytes, maybe more */
375 
376 		memset((char *)tempa, 0, sizeof(tempa));
377 		memcpy((char *)tempa, (const char *)fh, 14); /* ensure alignment */
378 		fsidp->Fsid_dev.Minor = tempa[0] + (tempa[1]<<1);
379 		fsidp->Fsid_dev.Major = tempa[2] + (tempa[3]<<1);
380 		fsidp->fsid_code = 0;
381 	    }
382 
383 	    /* VMS file ID is: (RVN, FidHi, FidLo) */
384 	    *inop = make_uint32(fhp[26], fhp[27], fhp[23], fhp[22]);
385 
386 	    /* Caller must save (and null-terminate?) this value */
387 	    if (fsnamep)
388 		*fsnamep = (const char *)&(fhp[1]);
389 
390 	    if (osnamep)
391 		*osnamep = "VMS";
392 	    break;
393 
394 	case FHT_AIX32:
395 	    fsidp->Fsid_dev.Minor = make_uint16(fhp[2], fhp[3]);
396 	    fsidp->Fsid_dev.Major = make_uint16(fhp[0], fhp[1]);
397 	    fsidp->fsid_code = make_uint32(fhp[4], fhp[5], fhp[6], fhp[7]);
398 
399 	    *inop = make_uint32(fhp[12], fhp[13], fhp[14], fhp[15]);
400 
401 	    if (osnamep)
402 		*osnamep = "AIX32";
403 	    break;
404 
405 	case FHT_HPUX9:
406 	    fsidp->Fsid_dev.Major = fhp[0];
407 	    temp = make_uint24(fhp[1], fhp[2], fhp[3]);
408 	    fsidp->Fsid_dev.Minor = temp;
409 	    fsidp->fsid_code = make_uint32(fhp[4], fhp[5], fhp[6], fhp[7]);
410 
411 	    *inop = make_uint32(fhp[12], fhp[13], fhp[14], fhp[15]);
412 
413 	    if (osnamep)
414 		*osnamep = "HPUX9";
415 	    break;
416 
417 	case FHT_UNKNOWN:
418 #ifdef DEBUG
419 	    /* XXX debugging */
420 	    for (i = 0; i < len*4; i++)
421 		(void)fprintf(stderr, "%x.", fhp[i]);
422 	    (void)fprintf(stderr, "\n");
423 #endif
424 	    /* Save the actual handle, so it can be display with -u */
425 	    for (i = 0; i < len*4 && i*2 < sizeof(fsidp->Opaque_Handle) - 1; i++)
426 	    	(void)snprintf(&(fsidp->Opaque_Handle[i*2]), 3, "%.2X", fhp[i]);
427 	    fsidp->Opaque_Handle[i*2] = '\0';
428 
429 	    /* XXX for now, give "bogus" values to aid debugging */
430 	    fsidp->fsid_code = 0;
431 	    fsidp->Fsid_dev.Minor = 257;
432 	    fsidp->Fsid_dev.Major = 257;
433 	    *inop = 1;
434 
435 	    /* display will show this string instead of (257,257) */
436 	    if (fsnamep)
437 		*fsnamep = "Unknown";
438 
439 	    if (osnamep)
440 		*osnamep = "Unknown";
441 	    break;
442 
443 	}
444 }
445 
446 /*
447  * Is this a VMS UCX file handle?
448  *	Check for:
449  *	(1) leading code byte	[XXX not yet]
450  *	(2) followed by string of printing chars & spaces
451  *	(3) followed by string of nulls
452  */
453 static int
454 is_UCX(const unsigned char *fhp, u_int len)
455 {
456 	register u_int i;
457 	int seen_null = 0;
458 
459 	/*
460 	 * Require at least 28 bytes of file handle; it's variable-length
461 	 * in NFSv3.  "len" is in units of 32-bit words, not bytes.
462 	 */
463 	if (len < 28/4)
464 		return(0);
465 
466 	for (i = 1; i < 14; i++) {
467 	    if (ND_ISPRINT(fhp[i])) {
468 		if (seen_null)
469 		   return(0);
470 		else
471 		   continue;
472 	    }
473 	    else if (fhp[i] == 0) {
474 		seen_null = 1;
475 		continue;
476 	    }
477 	    else
478 		return(0);
479 	}
480 
481 	return(1);
482 }
483