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-ctype.h"
53
54#include "netdissect.h"
55#include "extract.h"
56#include "nfsfh.h"
57
58/*
59 * This routine attempts to parse a file handle (in network byte order),
60 * using heuristics to guess what kind of format it is in.  See the
61 * file "fhandle_layouts" for a detailed description of the various
62 * patterns we know about.
63 *
64 * The file handle is parsed into our internal representation of a
65 * file-system id, and an internal representation of an inode-number.
66 */
67
68#define	FHT_UNKNOWN	0
69#define	FHT_AUSPEX	1
70#define	FHT_DECOSF	2
71#define	FHT_IRIX4	3
72#define	FHT_IRIX5	4
73#define	FHT_SUNOS3	5
74#define	FHT_SUNOS4	6
75#define	FHT_ULTRIX	7
76#define	FHT_VMSUCX	8
77#define	FHT_SUNOS5	9
78#define	FHT_AIX32	10
79#define	FHT_HPUX9	11
80#define	FHT_BSD44	12
81
82static int is_UCX(netdissect_options *, const unsigned char *, u_int);
83
84void
85Parse_fh(netdissect_options *ndo, const unsigned char *fh, u_int len,
86	 my_fsid *fsidp, uint32_t *inop,
87	 const char **osnamep, /* if non-NULL, return OS name here */
88	 const char **fsnamep, /* if non-NULL, return server fs name here (for VMS) */
89	 int ourself)	/* true if file handle was generated on this host */
90{
91	const unsigned char *fhp = fh;
92	uint32_t temp;
93	int fhtype = FHT_UNKNOWN;
94	u_int i;
95
96	/*
97	 * Require at least 16 bytes of file handle; it's variable-length
98	 * in NFSv3.  "len" is in units of 32-bit words, not bytes.
99	 */
100	if (len < 16/4)
101		fhtype = FHT_UNKNOWN;
102	else {
103		if (ourself) {
104		    /* File handle generated on this host, no need for guessing */
105#if	defined(IRIX40)
106		    fhtype = FHT_IRIX4;
107#endif
108#if	defined(IRIX50)
109		    fhtype = FHT_IRIX5;
110#endif
111#if	defined(IRIX51)
112		    fhtype = FHT_IRIX5;
113#endif
114#if	defined(SUNOS4)
115		    fhtype = FHT_SUNOS4;
116#endif
117#if	defined(SUNOS5)
118		    fhtype = FHT_SUNOS5;
119#endif
120#if	defined(ultrix)
121		    fhtype = FHT_ULTRIX;
122#endif
123#if	defined(__osf__)
124		    fhtype = FHT_DECOSF;
125#endif
126#if	defined(__NetBSD__) || defined(__FreeBSD__) || defined(__DragonFly__) \
127     || defined(__OpenBSD__)
128		    fhtype = FHT_BSD44;
129#endif
130		}
131		/*
132		 * This is basically a big decision tree
133		 */
134		else if ((GET_U_1(fhp) == 0) && (GET_U_1(fhp + 1) == 0)) {
135		    /* bytes[0,1] == (0,0); rules out Ultrix, IRIX5, SUNOS5 */
136		    /* probably rules out HP-UX, AIX unless they allow major=0 */
137		    if ((GET_U_1(fhp + 2) == 0) && (GET_U_1(fhp + 3) == 0)) {
138			/* bytes[2,3] == (0,0); must be Auspex */
139			/* XXX or could be Ultrix+MASSBUS "hp" disk? */
140			fhtype = FHT_AUSPEX;
141		    }
142		    else {
143			/*
144			 * bytes[2,3] != (0,0); rules out Auspex, could be
145			 * DECOSF, SUNOS4, or IRIX4
146			 */
147			if ((GET_U_1(fhp + 4) != 0) && (GET_U_1(fhp + 5) == 0) &&
148				(GET_U_1(fhp + 8) == 12) && (GET_U_1(fhp + 9) == 0)) {
149			    /* seems to be DECOSF, with minor == 0 */
150			    fhtype = FHT_DECOSF;
151			}
152			else {
153			    /* could be SUNOS4 or IRIX4 */
154			    /* XXX the test of fhp[5] == 8 could be wrong */
155			    if ((GET_U_1(fhp + 4) == 0) && (GET_U_1(fhp + 5) == 8) && (GET_U_1(fhp + 6) == 0) &&
156			        (GET_U_1(fhp + 7) == 0)) {
157				/* looks like a length, not a file system typecode */
158				fhtype = FHT_IRIX4;
159			    }
160			    else {
161				/* by elimination */
162				fhtype = FHT_SUNOS4;
163			    }
164			}
165		    }
166		}
167		else {
168		    /*
169		     * bytes[0,1] != (0,0); rules out Auspex, IRIX4, SUNOS4
170		     * could be IRIX5, DECOSF, UCX, Ultrix, SUNOS5
171		     * could be AIX, HP-UX
172		     */
173		    if ((GET_U_1(fhp + 2) == 0) && (GET_U_1(fhp + 3) == 0)) {
174			/*
175			 * bytes[2,3] == (0,0); rules out OSF, probably not UCX
176			 * (unless the exported device name is just one letter!),
177			 * could be Ultrix, IRIX5, AIX, or SUNOS5
178			 * might be HP-UX (depends on their values for minor devs)
179			 */
180			if ((GET_U_1(fhp + 6) == 0) && (GET_U_1(fhp + 7) == 0)) {
181			    fhtype = FHT_BSD44;
182			}
183			/*XXX we probably only need to test of these two bytes */
184			else if ((len >= 24/4) && (GET_U_1(fhp + 21) == 0) && (GET_U_1(fhp + 23) == 0)) {
185			    fhtype = FHT_ULTRIX;
186			}
187			else {
188			    /* Could be SUNOS5/IRIX5, maybe AIX */
189			    /* XXX no obvious difference between SUNOS5 and IRIX5 */
190			    if (GET_U_1(fhp + 9) == 10)
191				fhtype = FHT_SUNOS5;
192			    /* XXX what about AIX? */
193			}
194		    }
195		    else {
196			/*
197			 * bytes[2,3] != (0,0); rules out Ultrix, could be
198			 * DECOSF, SUNOS5, IRIX5, AIX, HP-UX, or UCX
199			 */
200			if ((GET_U_1(fhp + 8) == 12) && (GET_U_1(fhp + 9) == 0)) {
201			    fhtype = FHT_DECOSF;
202			}
203			else if ((GET_U_1(fhp + 8) == 0) && (GET_U_1(fhp + 9) == 10)) {
204			    /* could be SUNOS5/IRIX5, AIX, HP-UX */
205			    if ((GET_U_1(fhp + 7) == 0) && (GET_U_1(fhp + 6) == 0) &&
206				(GET_U_1(fhp + 5) == 0) && (GET_U_1(fhp + 4) == 0)) {
207				/* XXX is this always true of HP-UX? */
208				fhtype = FHT_HPUX9;
209			    }
210			    else if (GET_U_1(fhp + 7) == 2) {
211				/* This would be MNT_NFS on AIX, which is impossible */
212				fhtype = FHT_SUNOS5;	/* or maybe IRIX5 */
213			    }
214			    else {
215				/*
216				 * XXX Could be SUNOS5/IRIX5 or AIX.  I don't
217				 * XXX see any way to disambiguate these, so
218				 * XXX I'm going with the more likely guess.
219				 * XXX Sorry, Big Blue.
220				 */
221				fhtype = FHT_SUNOS5;	/* or maybe IRIX5 */
222			    }
223		        }
224			else {
225			    if (is_UCX(ndo, fhp, len)) {
226				fhtype = FHT_VMSUCX;
227			    }
228			    else {
229				fhtype = FHT_UNKNOWN;
230			    }
231			}
232		    }
233		}
234	}
235
236	/* XXX still needs to handle SUNOS3 */
237
238	switch (fhtype) {
239	case FHT_AUSPEX:
240	    fsidp->Fsid_dev.Minor = GET_U_1(fhp + 7);
241	    fsidp->Fsid_dev.Major = GET_U_1(fhp + 6);
242	    fsidp->fsid_code = 0;
243
244	    *inop = GET_BE_U_4(fhp + 12);
245
246	    if (osnamep)
247		*osnamep = "Auspex";
248	    break;
249
250	case FHT_BSD44:
251	    fsidp->Fsid_dev.Minor = GET_U_1(fhp);
252	    fsidp->Fsid_dev.Major = GET_U_1(fhp + 1);
253	    fsidp->fsid_code = 0;
254
255	    *inop = GET_LE_U_4(fhp + 12);
256
257	    if (osnamep)
258		*osnamep = "BSD 4.4";
259	    break;
260
261	case FHT_DECOSF:
262	    fsidp->fsid_code = GET_LE_U_4(fhp + 4);
263			/* XXX could ignore 3 high-order bytes */
264
265	    temp = GET_LE_U_4(fhp);
266	    fsidp->Fsid_dev.Minor = temp & 0xFFFFF;
267	    fsidp->Fsid_dev.Major = (temp>>20) & 0xFFF;
268
269	    *inop = GET_LE_U_4(fhp + 12);
270	    if (osnamep)
271		*osnamep = "OSF";
272	    break;
273
274	case FHT_IRIX4:
275	    fsidp->Fsid_dev.Minor = GET_U_1(fhp + 3);
276	    fsidp->Fsid_dev.Major = GET_U_1(fhp + 2);
277	    fsidp->fsid_code = 0;
278
279	    *inop = GET_BE_U_4(fhp + 8);
280
281	    if (osnamep)
282		*osnamep = "IRIX4";
283	    break;
284
285	case FHT_IRIX5:
286	    fsidp->Fsid_dev.Minor = GET_BE_U_2(fhp + 2);
287	    fsidp->Fsid_dev.Major = GET_BE_U_2(fhp);
288	    fsidp->fsid_code = GET_BE_U_4(fhp + 4);
289
290	    *inop = GET_BE_U_4(fhp + 12);
291
292	    if (osnamep)
293		*osnamep = "IRIX5";
294	    break;
295
296#ifdef notdef
297	case FHT_SUNOS3:
298	    /*
299	     * XXX - none of the heuristics above return this.
300	     * Are there any SunOS 3.x systems around to care about?
301	     */
302	    if (osnamep)
303		*osnamep = "SUNOS3";
304	    break;
305#endif
306
307	case FHT_SUNOS4:
308	    fsidp->Fsid_dev.Minor = GET_U_1(fhp + 3);
309	    fsidp->Fsid_dev.Major = GET_U_1(fhp + 2);
310	    fsidp->fsid_code = GET_BE_U_4(fhp + 4);
311
312	    *inop = GET_BE_U_4(fhp + 12);
313
314	    if (osnamep)
315		*osnamep = "SUNOS4";
316	    break;
317
318	case FHT_SUNOS5:
319	    temp = GET_BE_U_2(fhp);
320	    fsidp->Fsid_dev.Major = (temp>>2) &  0x3FFF;
321	    temp = GET_BE_U_3(fhp + 1);
322	    fsidp->Fsid_dev.Minor = temp & 0x3FFFF;
323	    fsidp->fsid_code = GET_BE_U_4(fhp + 4);
324
325	    *inop = GET_BE_U_4(fhp + 12);
326
327	    if (osnamep)
328		*osnamep = "SUNOS5";
329	    break;
330
331	case FHT_ULTRIX:
332	    fsidp->fsid_code = 0;
333	    fsidp->Fsid_dev.Minor = GET_U_1(fhp);
334	    fsidp->Fsid_dev.Major = GET_U_1(fhp + 1);
335
336	    temp = GET_LE_U_4(fhp + 4);
337	    *inop = temp;
338	    if (osnamep)
339		*osnamep = "Ultrix";
340	    break;
341
342	case FHT_VMSUCX:
343	    /* No numeric file system ID, so hash on the device-name */
344	    if (sizeof(*fsidp) >= 14) {
345		if (sizeof(*fsidp) > 14)
346		    memset((char *)fsidp, 0, sizeof(*fsidp));
347		/* just use the whole thing */
348		memcpy((char *)fsidp, (const char *)fh, 14);
349	    }
350	    else {
351		uint32_t tempa[4];	/* at least 16 bytes, maybe more */
352
353		memset((char *)tempa, 0, sizeof(tempa));
354		memcpy((char *)tempa, (const char *)fh, 14); /* ensure alignment */
355		fsidp->Fsid_dev.Minor = tempa[0] + (tempa[1]<<1);
356		fsidp->Fsid_dev.Major = tempa[2] + (tempa[3]<<1);
357		fsidp->fsid_code = 0;
358	    }
359
360	    /* VMS file ID is: (RVN, FidHi, FidLo) */
361	    *inop = (((uint32_t) GET_U_1(fhp + 26)) << 24) |
362		    (((uint32_t) GET_U_1(fhp + 27)) << 16) |
363		    (GET_LE_U_2(fhp + 22) << 0);
364
365	    /* Caller must save (and null-terminate?) this value */
366	    if (fsnamep)
367		*fsnamep = (const char *)(fhp + 1);
368
369	    if (osnamep)
370		*osnamep = "VMS";
371	    break;
372
373	case FHT_AIX32:
374	    fsidp->Fsid_dev.Minor = GET_BE_U_2(fhp + 2);
375	    fsidp->Fsid_dev.Major = GET_BE_U_2(fhp);
376	    fsidp->fsid_code = GET_BE_U_4(fhp + 4);
377
378	    *inop = GET_BE_U_4(fhp + 12);
379
380	    if (osnamep)
381		*osnamep = "AIX32";
382	    break;
383
384	case FHT_HPUX9:
385	    fsidp->Fsid_dev.Major = GET_U_1(fhp);
386	    temp = GET_BE_U_3(fhp + 1);
387	    fsidp->Fsid_dev.Minor = temp;
388	    fsidp->fsid_code = GET_BE_U_4(fhp + 4);
389
390	    *inop = GET_BE_U_4(fhp + 12);
391
392	    if (osnamep)
393		*osnamep = "HPUX9";
394	    break;
395
396	case FHT_UNKNOWN:
397#ifdef DEBUG
398	    /* XXX debugging */
399	    for (i = 0; i < len*4; i++)
400		(void)fprintf(stderr, "%x.", GET_U_1(fhp + i));
401	    (void)fprintf(stderr, "\n");
402#endif
403	    /* Save the actual handle, so it can be display with -u */
404	    for (i = 0; i < len*4 && i*2 < sizeof(fsidp->Opaque_Handle) - 1; i++)
405		(void)snprintf(&(fsidp->Opaque_Handle[i*2]), 3, "%.2X",
406			       GET_U_1(fhp + i));
407	    fsidp->Opaque_Handle[i*2] = '\0';
408
409	    /* XXX for now, give "bogus" values to aid debugging */
410	    fsidp->fsid_code = 0;
411	    fsidp->Fsid_dev.Minor = 257;
412	    fsidp->Fsid_dev.Major = 257;
413	    *inop = 1;
414
415	    /* display will show this string instead of (257,257) */
416	    if (fsnamep)
417		*fsnamep = "Unknown";
418
419	    if (osnamep)
420		*osnamep = "Unknown";
421	    break;
422
423	}
424}
425
426/*
427 * Is this a VMS UCX file handle?
428 *	Check for:
429 *	(1) leading code byte	[XXX not yet]
430 *	(2) followed by string of printing chars & spaces
431 *	(3) followed by string of nulls
432 */
433static int
434is_UCX(netdissect_options *ndo, const unsigned char *fhp, u_int len)
435{
436	u_int i;
437	int seen_null = 0;
438
439	/*
440	 * Require at least 28 bytes of file handle; it's variable-length
441	 * in NFSv3.  "len" is in units of 32-bit words, not bytes.
442	 */
443	if (len < 28/4)
444		return(0);
445
446	for (i = 1; i < 14; i++) {
447	    if (ND_ASCII_ISPRINT(GET_U_1(fhp + i))) {
448		if (seen_null)
449		   return(0);
450		else
451		   continue;
452	    }
453	    else if (GET_U_1(fhp + i) == 0) {
454		seen_null = 1;
455		continue;
456	    }
457	    else
458		return(0);
459	}
460
461	return(1);
462}
463