xref: /netbsd-src/external/bsd/tcpdump/dist/parsenfsfh.c (revision bdc22b2e01993381dcefeff2bc9b56ca75a4235c)
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 #include <sys/cdefs.h>
44 #ifndef lint
45 __RCSID("$NetBSD: parsenfsfh.c,v 1.8 2017/02/05 04:05:05 spz Exp $");
46 #endif
47 
48 #ifdef HAVE_CONFIG_H
49 #include "config.h"
50 #endif
51 
52 #include <netdissect-stdinc.h>
53 
54 #include <stdio.h>
55 #include <string.h>
56 
57 #include "netdissect.h"
58 #include "nfsfh.h"
59 
60 /*
61  * This routine attempts to parse a file handle (in network byte order),
62  * using heuristics to guess what kind of format it is in.  See the
63  * file "fhandle_layouts" for a detailed description of the various
64  * patterns we know about.
65  *
66  * The file handle is parsed into our internal representation of a
67  * file-system id, and an internal representation of an inode-number.
68  */
69 
70 #define	FHT_UNKNOWN	0
71 #define	FHT_AUSPEX	1
72 #define	FHT_DECOSF	2
73 #define	FHT_IRIX4	3
74 #define	FHT_IRIX5	4
75 #define	FHT_SUNOS3	5
76 #define	FHT_SUNOS4	6
77 #define	FHT_ULTRIX	7
78 #define	FHT_VMSUCX	8
79 #define	FHT_SUNOS5	9
80 #define	FHT_AIX32	10
81 #define	FHT_HPUX9	11
82 #define	FHT_BSD44	12
83 #define	FHT_NETBSD	13
84 
85 #ifdef	ultrix
86 /* Nasty hack to keep the Ultrix C compiler from emitting bogus warnings */
87 #define	XFF(x)	((uint32_t)(x))
88 #else
89 #define	XFF(x)	(x)
90 #endif
91 
92 #define	make_uint32(msb,b,c,lsb)\
93 	(XFF(lsb) + (XFF(c)<<8) + (XFF(b)<<16) + (XFF(msb)<<24))
94 
95 #define	make_uint24(msb,b, lsb)\
96 	(XFF(lsb) + (XFF(b)<<8) + (XFF(msb)<<16))
97 
98 #define	make_uint16(msb,lsb)\
99 	(XFF(lsb) + (XFF(msb)<<8))
100 
101 #ifdef	__alpha
102 	/* or other 64-bit systems */
103 #define	make_uint48(msb,b,c,d,e,lsb)\
104 	((lsb) + ((e)<<8) + ((d)<<16) + ((c)<<24) + ((b)<<32) + ((msb)<<40))
105 #else
106 	/* on 32-bit systems ignore high-order bits */
107 #define	make_uint48(msb,b,c,d,e,lsb)\
108 	((lsb) + ((e)<<8) + ((d)<<16) + ((c)<<24))
109 #endif
110 
111 static int is_UCX(const unsigned char *, u_int);
112 
113 void
114 Parse_fh(register const unsigned char *fh, u_int len, my_fsid *fsidp,
115 	 uint32_t *inop,
116 	 const char **osnamep, /* if non-NULL, return OS name here */
117 	 const char **fsnamep, /* if non-NULL, return server fs name here (for VMS) */
118 	 int ourself)	/* true if file handle was generated on this host */
119 {
120 	register const unsigned char *fhp = fh;
121 	uint32_t temp;
122 	int fhtype = FHT_UNKNOWN;
123 	u_int i;
124 
125 	/*
126 	 * Require at least 16 bytes of file handle; it's variable-length
127 	 * in NFSv3.  "len" is in units of 32-bit words, not bytes.
128 	 */
129 	if (len < 16/4)
130 	    fhtype = FHT_UNKNOWN;
131 	else {
132 	    if (ourself) {
133 		/* File handle generated on this host, no need for guessing */
134 #if	defined(IRIX40)
135 		fhtype = FHT_IRIX4;
136 #endif
137 #if	defined(IRIX50)
138 		fhtype = FHT_IRIX5;
139 #endif
140 #if	defined(IRIX51)
141 		fhtype = FHT_IRIX5;
142 #endif
143 #if	defined(SUNOS4)
144 		fhtype = FHT_SUNOS4;
145 #endif
146 #if	defined(SUNOS5)
147 		fhtype = FHT_SUNOS5;
148 #endif
149 #if	defined(ultrix)
150 		fhtype = FHT_ULTRIX;
151 #endif
152 #if	defined(__osf__)
153 		fhtype = FHT_DECOSF;
154 #endif
155 #if	defined(__FreeBSD__) || defined(__DragonFly__) || defined(__OpenBSD__)
156 		fhtype = FHT_BSD44;
157 #endif
158 #if	defined(__NetBSD__)
159 		fhtype = FHT_NETBSD;
160 #endif
161 	    }
162 	    /*
163 	     * This is basically a big decision tree
164 	     */
165 	    else if ((fhp[0] == 0) && (fhp[1] == 0)) {
166 		/* bytes[0,1] == (0,0); rules out Ultrix, IRIX5, SUNOS5 */
167 		/* probably rules out HP-UX, AIX unless they allow major=0 */
168 		if ((fhp[2] == 0) && (fhp[3] == 0)) {
169 		    /* bytes[2,3] == (0,0); must be Auspex */
170 		    /* XXX or could be Ultrix+MASSBUS "hp" disk? */
171 		    fhtype = FHT_AUSPEX;
172 		}
173 		else {
174 		    /*
175 		     * bytes[2,3] != (0,0); rules out Auspex, could be
176 		     * DECOSF, SUNOS4, or IRIX4
177 		     */
178 		    if ((fhp[4] != 0) && (fhp[5] == 0) &&
179 			    (fhp[8] == 12) && (fhp[9] == 0)) {
180 			/* seems to be DECOSF, with minor == 0 */
181 			fhtype = FHT_DECOSF;
182 		    }
183 		    else {
184 			/* could be SUNOS4 or IRIX4 */
185 			/* XXX the test of fhp[5] == 8 could be wrong */
186 			if ((fhp[4] == 0) && (fhp[5] == 8) && (fhp[6] == 0) &&
187 			    (fhp[7] == 0)) {
188 			    /* looks like a length, not a file system typecode */
189 			    fhtype = FHT_IRIX4;
190 			}
191 			else {
192 			    /* by elimination */
193 			    fhtype = FHT_SUNOS4;
194 			}
195 		    }
196 		}
197 	    }
198 	    else {
199 		/*
200 		 * bytes[0,1] != (0,0); rules out Auspex, IRIX4, SUNOS4
201 		 * could be IRIX5, DECOSF, UCX, Ultrix, SUNOS5
202 		 * could be AIX, HP-UX
203 		 */
204 		if ((fhp[2] == 0) && (fhp[3] == 0)) {
205 		    /*
206 		     * bytes[2,3] == (0,0); rules out OSF, probably not UCX
207 		     * (unless the exported device name is just one letter!),
208 		     * could be Ultrix, IRIX5, AIX, or SUNOS5
209 		     * might be HP-UX (depends on their values for minor devs)
210 		     */
211 		    if ((fhp[6] == 0) && (fhp[7] == 0)) {
212 			/* for ffs sizeof(ufid) == 16 bytes */
213 			if ((fhp[8] == 0x10 && fhp[9] == 0x0) ||
214 			    (fhp[9] == 0x0 && fhp[9] == 0x10))
215 				fhtype = FHT_NETBSD;
216 			else
217 				fhtype = FHT_BSD44;
218 		    }
219 		    /*XXX we probably only need to test of these two bytes */
220 		    else if ((len >= 24/4) && (fhp[21] == 0) && (fhp[23] == 0)) {
221 			fhtype = FHT_ULTRIX;
222 		    }
223 		    else {
224 			/* Could be SUNOS5/IRIX5, maybe AIX */
225 			/* XXX no obvious difference between SUNOS5 and IRIX5 */
226 			if (fhp[9] == 10)
227 			    fhtype = FHT_SUNOS5;
228 			/* XXX what about AIX? */
229 		    }
230 		}
231 		else {
232 		    /*
233 		     * bytes[2,3] != (0,0); rules out Ultrix, could be
234 		     * DECOSF, SUNOS5, IRIX5, AIX, HP-UX, or UCX
235 		     */
236 		    if ((fhp[8] == 12) && (fhp[9] == 0)) {
237 			fhtype = FHT_DECOSF;
238 		    }
239 		    else if ((fhp[8] == 0) && (fhp[9] == 10)) {
240 			/* could be SUNOS5/IRIX5, AIX, HP-UX */
241 			if ((fhp[7] == 0) && (fhp[6] == 0) &&
242 			    (fhp[5] == 0) && (fhp[4] == 0)) {
243 			    /* XXX is this always true of HP-UX? */
244 			    fhtype = FHT_HPUX9;
245 			}
246 			else if (fhp[7] == 2) {
247 			    /* This would be MNT_NFS on AIX, which is impossible */
248 			    fhtype = FHT_SUNOS5;	/* or maybe IRIX5 */
249 			}
250 			else {
251 			    /*
252 			     * XXX Could be SUNOS5/IRIX5 or AIX.  I don't
253 			     * XXX see any way to disambiguate these, so
254 			     * XXX I'm going with the more likely guess.
255 			     * XXX Sorry, Big Blue.
256 			     */
257 			    fhtype = FHT_SUNOS5;	/* or maybe IRIX5 */
258 			}
259 		    }
260 		    else {
261 			if (is_UCX(fhp, len)) {
262 			    fhtype = FHT_VMSUCX;
263 			}
264 			else {
265 			    fhtype = FHT_UNKNOWN;
266 			}
267 		    }
268 		}
269 	    }
270 	}
271 
272 	/* XXX still needs to handle SUNOS3 */
273 
274 	switch (fhtype) {
275 	case FHT_AUSPEX:
276 	    fsidp->Fsid_dev.Minor = fhp[7];
277 	    fsidp->Fsid_dev.Major = fhp[6];
278 	    fsidp->fsid_code = 0;
279 
280 	    *inop = make_uint32(fhp[12], fhp[13], fhp[14], fhp[15]);
281 
282 	    if (osnamep)
283 		*osnamep = "Auspex";
284 	    break;
285 
286 	case FHT_BSD44:
287 	case FHT_NETBSD:
288 	    fsidp->Fsid_dev.Minor = fhp[0];
289 	    fsidp->Fsid_dev.Major = fhp[1];
290 	    fsidp->fsid_code = 0;
291 
292 	    /*
293 	     * NetBSD puts the generation number before the inode; inode
294 	     * is 64 bits, but only 32 are typically used; XXX endian issues?
295 	     */
296 	    if (fhtype == FHT_NETBSD)
297 		    *inop = make_uint32(fhp[19], fhp[18], fhp[17], fhp[16]);
298 	    else
299 		    *inop = make_uint32(fhp[15], fhp[14], fhp[13], fhp[12]);
300 
301 	    if (osnamep)
302 		*osnamep = "BSD 4.4";
303 	    break;
304 
305 	case FHT_DECOSF:
306 	    fsidp->fsid_code = make_uint32(fhp[7], fhp[6], fhp[5], fhp[4]);
307 			/* XXX could ignore 3 high-order bytes */
308 
309 	    temp = make_uint32(fhp[3], fhp[2], fhp[1], fhp[0]);
310 	    fsidp->Fsid_dev.Minor = temp & 0xFFFFF;
311 	    fsidp->Fsid_dev.Major = (temp>>20) & 0xFFF;
312 
313 	    *inop = make_uint32(fhp[15], fhp[14], fhp[13], fhp[12]);
314 	    if (osnamep)
315 		*osnamep = "OSF";
316 	    break;
317 
318 	case FHT_IRIX4:
319 	    fsidp->Fsid_dev.Minor = fhp[3];
320 	    fsidp->Fsid_dev.Major = fhp[2];
321 	    fsidp->fsid_code = 0;
322 
323 	    *inop = make_uint32(fhp[8], fhp[9], fhp[10], fhp[11]);
324 
325 	    if (osnamep)
326 		*osnamep = "IRIX4";
327 	    break;
328 
329 	case FHT_IRIX5:
330 	    fsidp->Fsid_dev.Minor = make_uint16(fhp[2], fhp[3]);
331 	    fsidp->Fsid_dev.Major = make_uint16(fhp[0], fhp[1]);
332 	    fsidp->fsid_code = make_uint32(fhp[4], fhp[5], fhp[6], fhp[7]);
333 
334 	    *inop = make_uint32(fhp[12], fhp[13], fhp[14], fhp[15]);
335 
336 	    if (osnamep)
337 		*osnamep = "IRIX5";
338 	    break;
339 
340 #ifdef notdef
341 	case FHT_SUNOS3:
342 	    /*
343 	     * XXX - none of the heuristics above return this.
344 	     * Are there any SunOS 3.x systems around to care about?
345 	     */
346 	    if (osnamep)
347 		*osnamep = "SUNOS3";
348 	    break;
349 #endif
350 
351 	case FHT_SUNOS4:
352 	    fsidp->Fsid_dev.Minor = fhp[3];
353 	    fsidp->Fsid_dev.Major = fhp[2];
354 	    fsidp->fsid_code = make_uint32(fhp[4], fhp[5], fhp[6], fhp[7]);
355 
356 	    *inop = make_uint32(fhp[12], fhp[13], fhp[14], fhp[15]);
357 
358 	    if (osnamep)
359 		*osnamep = "SUNOS4";
360 	    break;
361 
362 	case FHT_SUNOS5:
363 	    temp = make_uint16(fhp[0], fhp[1]);
364 	    fsidp->Fsid_dev.Major = (temp>>2) &  0x3FFF;
365 	    temp = make_uint24(fhp[1], fhp[2], fhp[3]);
366 	    fsidp->Fsid_dev.Minor = temp & 0x3FFFF;
367 	    fsidp->fsid_code = make_uint32(fhp[4], fhp[5], fhp[6], fhp[7]);
368 
369 	    *inop = make_uint32(fhp[12], fhp[13], fhp[14], fhp[15]);
370 
371 	    if (osnamep)
372 		*osnamep = "SUNOS5";
373 	    break;
374 
375 	case FHT_ULTRIX:
376 	    fsidp->fsid_code = 0;
377 	    fsidp->Fsid_dev.Minor = fhp[0];
378 	    fsidp->Fsid_dev.Major = fhp[1];
379 
380 	    temp = make_uint32(fhp[7], fhp[6], fhp[5], fhp[4]);
381 	    *inop = temp;
382 	    if (osnamep)
383 		*osnamep = "Ultrix";
384 	    break;
385 
386 	case FHT_VMSUCX:
387 	    /* No numeric file system ID, so hash on the device-name */
388 	    if (sizeof(*fsidp) >= 14) {
389 		if (sizeof(*fsidp) > 14)
390 		    memset((char *)fsidp, 0, sizeof(*fsidp));
391 		/* just use the whole thing */
392 		memcpy((char *)fsidp, (const char *)fh, 14);
393 	    }
394 	    else {
395 		uint32_t tempa[4];	/* at least 16 bytes, maybe more */
396 
397 		memset((char *)tempa, 0, sizeof(tempa));
398 		memcpy((char *)tempa, (const char *)fh, 14); /* ensure alignment */
399 		fsidp->Fsid_dev.Minor = tempa[0] + (tempa[1]<<1);
400 		fsidp->Fsid_dev.Major = tempa[2] + (tempa[3]<<1);
401 		fsidp->fsid_code = 0;
402 	    }
403 
404 	    /* VMS file ID is: (RVN, FidHi, FidLo) */
405 	    *inop = make_uint32(fhp[26], fhp[27], fhp[23], fhp[22]);
406 
407 	    /* Caller must save (and null-terminate?) this value */
408 	    if (fsnamep)
409 		*fsnamep = (const char *)&(fhp[1]);
410 
411 	    if (osnamep)
412 		*osnamep = "VMS";
413 	    break;
414 
415 	case FHT_AIX32:
416 	    fsidp->Fsid_dev.Minor = make_uint16(fhp[2], fhp[3]);
417 	    fsidp->Fsid_dev.Major = make_uint16(fhp[0], fhp[1]);
418 	    fsidp->fsid_code = make_uint32(fhp[4], fhp[5], fhp[6], fhp[7]);
419 
420 	    *inop = make_uint32(fhp[12], fhp[13], fhp[14], fhp[15]);
421 
422 	    if (osnamep)
423 		*osnamep = "AIX32";
424 	    break;
425 
426 	case FHT_HPUX9:
427 	    fsidp->Fsid_dev.Major = fhp[0];
428 	    temp = make_uint24(fhp[1], fhp[2], fhp[3]);
429 	    fsidp->Fsid_dev.Minor = temp;
430 	    fsidp->fsid_code = make_uint32(fhp[4], fhp[5], fhp[6], fhp[7]);
431 
432 	    *inop = make_uint32(fhp[12], fhp[13], fhp[14], fhp[15]);
433 
434 	    if (osnamep)
435 		*osnamep = "HPUX9";
436 	    break;
437 
438 	case FHT_UNKNOWN:
439 #ifdef DEBUG
440 	    /* XXX debugging */
441 	    for (i = 0; i < len*4; i++)
442 		(void)fprintf(stderr, "%x.", fhp[i]);
443 	    (void)fprintf(stderr, "\n");
444 #endif
445 	    /* Save the actual handle, so it can be display with -u */
446 	    for (i = 0; i < len*4 && i*2 < sizeof(fsidp->Opaque_Handle) - 1; i++)
447 	    	(void)snprintf(&(fsidp->Opaque_Handle[i*2]), 3, "%.2X", fhp[i]);
448 	    fsidp->Opaque_Handle[i*2] = '\0';
449 
450 	    /* XXX for now, give "bogus" values to aid debugging */
451 	    fsidp->fsid_code = 0;
452 	    fsidp->Fsid_dev.Minor = 257;
453 	    fsidp->Fsid_dev.Major = 257;
454 	    *inop = 1;
455 
456 	    /* display will show this string instead of (257,257) */
457 	    if (fsnamep)
458 		*fsnamep = "Unknown";
459 
460 	    if (osnamep)
461 		*osnamep = "Unknown";
462 	    break;
463 
464 	}
465 }
466 
467 /*
468  * Is this a VMS UCX file handle?
469  *	Check for:
470  *	(1) leading code byte	[XXX not yet]
471  *	(2) followed by string of printing chars & spaces
472  *	(3) followed by string of nulls
473  */
474 static int
475 is_UCX(const unsigned char *fhp, u_int len)
476 {
477 	register u_int i;
478 	int seen_null = 0;
479 
480 	/*
481 	 * Require at least 28 bytes of file handle; it's variable-length
482 	 * in NFSv3.  "len" is in units of 32-bit words, not bytes.
483 	 */
484 	if (len < 28/4)
485 		return(0);
486 
487 	for (i = 1; i < 14; i++) {
488 	    if (ND_ISPRINT(fhp[i])) {
489 		if (seen_null)
490 		   return(0);
491 		else
492 		   continue;
493 	    }
494 	    else if (fhp[i] == 0) {
495 		seen_null = 1;
496 		continue;
497 	    }
498 	    else
499 		return(0);
500 	}
501 
502 	return(1);
503 }
504