xref: /freebsd/contrib/tcpdump/parsenfsfh.c (revision a88113a83091fa398943e3c86bacb00932e947bf)
1 /*
2  * parsenfsfh.c - portable parser for NFS file handles
3  *			uses all sorts of heuristics
4  *
5  * Jeffrey C. Mogul
6  * Digital Equipment Corporation
7  * Western Research Laboratory
8  *
9  * $FreeBSD$
10  */
11 
12 #ifndef lint
13 static const char rcsid[] =
14     "@(#) $Header: /tcpdump/master/tcpdump/parsenfsfh.c,v 1.16 1999/11/21 09:36:47 fenner Exp $ (LBL)";
15 #endif
16 
17 #ifdef HAVE_CONFIG_H
18 #include "config.h"
19 #endif
20 
21 #include <sys/types.h>
22 #include <sys/time.h>
23 
24 #include <ctype.h>
25 #ifdef HAVE_MEMORY_H
26 #include <memory.h>
27 #endif
28 #include <stdio.h>
29 #include <string.h>
30 
31 #include "interface.h"
32 #include "nfsfh.h"
33 
34 /*
35  * This routine attempts to parse a file handle (in network byte order),
36  * using heuristics to guess what kind of format it is in.  See the
37  * file "fhandle_layouts" for a detailed description of the various
38  * patterns we know about.
39  *
40  * The file handle is parsed into our internal representation of a
41  * file-system id, and an internal representation of an inode-number.
42  */
43 
44 #define	FHT_UNKNOWN	0
45 #define	FHT_AUSPEX	1
46 #define	FHT_DECOSF	2
47 #define	FHT_IRIX4	3
48 #define	FHT_IRIX5	4
49 #define	FHT_SUNOS3	5
50 #define	FHT_SUNOS4	6
51 #define	FHT_ULTRIX	7
52 #define	FHT_VMSUCX	8
53 #define	FHT_SUNOS5	9
54 #define	FHT_AIX32	10
55 #define	FHT_HPUX9	11
56 
57 #ifdef	ultrix
58 /* Nasty hack to keep the Ultrix C compiler from emitting bogus warnings */
59 #define	XFF(x)	((u_int32_t)(x))
60 #else
61 #define	XFF(x)	(x)
62 #endif
63 
64 #define	make_uint32(msb,b,c,lsb)\
65 	(XFF(lsb) + (XFF(c)<<8) + (XFF(b)<<16) + (XFF(msb)<<24))
66 
67 #define	make_uint24(msb,b, lsb)\
68 	(XFF(lsb) + (XFF(b)<<8) + (XFF(msb)<<16))
69 
70 #define	make_uint16(msb,lsb)\
71 	(XFF(lsb) + (XFF(msb)<<8))
72 
73 #ifdef	__alpha
74 	/* or other 64-bit systems */
75 #define	make_uint48(msb,b,c,d,e,lsb)\
76 	((lsb) + ((e)<<8) + ((d)<<16) + ((c)<<24) + ((b)<<32) + ((msb)<<40))
77 #else
78 	/* on 32-bit systems ignore high-order bits */
79 #define	make_uint48(msb,b,c,d,e,lsb)\
80 	((lsb) + ((e)<<8) + ((d)<<16) + ((c)<<24))
81 #endif
82 
83 static int is_UCX(unsigned char *);
84 
85 void
86 Parse_fh(fh, len, fsidp, inop, osnamep, fsnamep, ourself)
87 register caddr_t *fh;
88 int len;
89 my_fsid *fsidp;
90 ino_t *inop;
91 char **osnamep;		/* if non-NULL, return OS name here */
92 char **fsnamep;		/* if non-NULL, return server fs name here (for VMS) */
93 int ourself;		/* true if file handle was generated on this host */
94 {
95 	register unsigned char *fhp = (unsigned char *)fh;
96 	u_int32_t temp;
97 	int fhtype = FHT_UNKNOWN;
98 
99 	if (ourself) {
100 	    /* File handle generated on this host, no need for guessing */
101 #if	defined(IRIX40)
102 	    fhtype = FHT_IRIX4;
103 #endif
104 #if	defined(IRIX50)
105 	    fhtype = FHT_IRIX5;
106 #endif
107 #if	defined(IRIX51)
108 	    fhtype = FHT_IRIX5;
109 #endif
110 #if	defined(SUNOS4)
111 	    fhtype = FHT_SUNOS4;
112 #endif
113 #if	defined(SUNOS5)
114 	    fhtype = FHT_SUNOS5;
115 #endif
116 #if	defined(ultrix)
117 	    fhtype = FHT_ULTRIX;
118 #endif
119 #if	defined(__osf__)
120 	    fhtype = FHT_DECOSF;
121 #endif
122 	}
123 	/*
124 	 * This is basically a big decision tree
125 	 */
126 	else if ((fhp[0] == 0) && (fhp[1] == 0)) {
127 	    /* bytes[0,1] == (0,0); rules out Ultrix, IRIX5, SUNOS5 */
128 	    /* probably rules out HP-UX, AIX unless they allow major=0 */
129 	    if ((fhp[2] == 0) && (fhp[3] == 0)) {
130 		/* bytes[2,3] == (0,0); must be Auspex */
131 		/* XXX or could be Ultrix+MASSBUS "hp" disk? */
132 		fhtype = FHT_AUSPEX;
133 	    }
134 	    else {
135 		/*
136 		 * bytes[2,3] != (0,0); rules out Auspex, could be
137 		 * DECOSF, SUNOS4, or IRIX4
138 		 */
139 		if ((fhp[4] != 0) && (fhp[5] == 0) &&
140 			(fhp[8] == 12) && (fhp[9] == 0)) {
141 		    /* seems to be DECOSF, with minor == 0 */
142 		    fhtype = FHT_DECOSF;
143 		}
144 		else {
145 		    /* could be SUNOS4 or IRIX4 */
146 		    /* XXX the test of fhp[5] == 8 could be wrong */
147 		    if ((fhp[4] == 0) && (fhp[5] == 8) && (fhp[6] == 0) &&
148 			(fhp[7] == 0)) {
149 			/* looks like a length, not a file system typecode */
150 			fhtype = FHT_IRIX4;
151 		    }
152 		    else {
153 			/* by elimination */
154 			fhtype = FHT_SUNOS4;
155 		    }
156 		}
157 	    }
158 	}
159 	else {
160 	    /*
161 	     * bytes[0,1] != (0,0); rules out Auspex, IRIX4, SUNOS4
162 	     * could be IRIX5, DECOSF, UCX, Ultrix, SUNOS5
163 	     * could be AIX, HP-UX
164 	     */
165 	    if ((fhp[2] == 0) && (fhp[3] == 0)) {
166 		/*
167 		 * bytes[2,3] == (0,0); rules out OSF, probably not UCX
168 		 * (unless the exported device name is just one letter!),
169 		 * could be Ultrix, IRIX5, AIX, or SUNOS5
170 		 * might be HP-UX (depends on their values for minor devs)
171 		 */
172 		/*XXX we probably only need to test of these two bytes */
173 		if ((fhp[21] == 0) && (fhp[23] == 0)) {
174 		    fhtype = FHT_ULTRIX;
175 		}
176 		else {
177 		    /* Could be SUNOS5/IRIX5, maybe AIX */
178 		    /* XXX no obvious difference between SUNOS5 and IRIX5 */
179 		    if (fhp[9] == 10)
180 			fhtype = FHT_SUNOS5;
181 		    /* XXX what about AIX? */
182 		}
183 	    }
184 	    else {
185 		/*
186 		 * bytes[2,3] != (0,0); rules out Ultrix, could be
187 		 * DECOSF, SUNOS5, IRIX5, AIX, HP-UX, or UCX
188 		 */
189 		if ((fhp[8] == 12) && (fhp[9] == 0)) {
190 		    fhtype = FHT_DECOSF;
191 		}
192 		else if ((fhp[8] == 0) && (fhp[9] == 10)) {
193 		    /* could be SUNOS5/IRIX5, AIX, HP-UX */
194 		    if ((fhp[7] == 0) && (fhp[6] == 0) &&
195 			(fhp[5] == 0) && (fhp[4] == 0)) {
196 			/* XXX is this always true of HP-UX? */
197 			fhtype = FHT_HPUX9;
198 		    }
199 		    else if (fhp[7] == 2) {
200 			/* This would be MNT_NFS on AIX, which is impossible */
201 			fhtype = FHT_SUNOS5;	/* or maybe IRIX5 */
202 		    }
203 		    else {
204 			/*
205 			 * XXX Could be SUNOS5/IRIX5 or AIX.  I don't
206 			 * XXX see any way to disambiguate these, so
207 			 * XXX I'm going with the more likely guess.
208 			 * XXX Sorry, Big Blue.
209 			 */
210 			fhtype = FHT_SUNOS5;	/* or maybe IRIX5 */
211 		    }
212 	        }
213 		else {
214 		    if (is_UCX(fhp)) {
215 			fhtype = FHT_VMSUCX;
216 		    }
217 		    else {
218 			fhtype = FHT_UNKNOWN;
219 		    }
220 		}
221 	    }
222 	}
223 
224 	/* XXX still needs to handle SUNOS3 */
225 
226 	switch (fhtype) {
227 	case FHT_AUSPEX:
228 	    fsidp->Fsid_dev.Minor = fhp[7];
229 	    fsidp->Fsid_dev.Major = fhp[6];
230 	    fsidp->fsid_code = 0;
231 
232 	    temp = make_uint32(fhp[12], fhp[13], fhp[14], fhp[15]);
233 	    *inop = temp;
234 
235 	    if (osnamep)
236 		*osnamep = "Auspex";
237 	    break;
238 
239 	case FHT_DECOSF:
240 	    fsidp->fsid_code = make_uint32(fhp[7], fhp[6], fhp[5], fhp[4]);
241 			/* XXX could ignore 3 high-order bytes */
242 
243 	    temp = make_uint32(fhp[3], fhp[2], fhp[1], fhp[0]);
244 	    fsidp->Fsid_dev.Minor = temp & 0xFFFFF;
245 	    fsidp->Fsid_dev.Major = (temp>>20) & 0xFFF;
246 
247 	    temp = make_uint32(fhp[15], fhp[14], fhp[13], fhp[12]);
248 	    *inop = temp;
249 	    if (osnamep)
250 		*osnamep = "OSF";
251 	    break;
252 
253 	case FHT_IRIX4:
254 	    fsidp->Fsid_dev.Minor = fhp[3];
255 	    fsidp->Fsid_dev.Major = fhp[2];
256 	    fsidp->fsid_code = 0;
257 
258 	    temp = make_uint32(fhp[8], fhp[9], fhp[10], fhp[11]);
259 	    *inop = temp;
260 
261 	    if (osnamep)
262 		*osnamep = "IRIX4";
263 	    break;
264 
265 	case FHT_IRIX5:
266 	    fsidp->Fsid_dev.Minor = make_uint16(fhp[2], fhp[3]);
267 	    fsidp->Fsid_dev.Major = make_uint16(fhp[0], fhp[1]);
268 	    fsidp->fsid_code = make_uint32(fhp[4], fhp[5], fhp[6], fhp[7]);
269 
270 	    temp = make_uint32(fhp[12], fhp[13], fhp[14], fhp[15]);
271 	    *inop = temp;
272 
273 	    if (osnamep)
274 		*osnamep = "IRIX5";
275 	    break;
276 
277 	case FHT_SUNOS3:
278 	    if (osnamep)
279 		*osnamep = "SUNOS3";
280 	    break;
281 
282 	case FHT_SUNOS4:
283 	    fsidp->Fsid_dev.Minor = fhp[3];
284 	    fsidp->Fsid_dev.Major = fhp[2];
285 	    fsidp->fsid_code = make_uint32(fhp[4], fhp[5], fhp[6], fhp[7]);
286 
287 	    temp = make_uint32(fhp[12], fhp[13], fhp[14], fhp[15]);
288 	    *inop = temp;
289 
290 	    if (osnamep)
291 		*osnamep = "SUNOS4";
292 	    break;
293 
294 	case FHT_SUNOS5:
295 	    temp = make_uint16(fhp[0], fhp[1]);
296 	    fsidp->Fsid_dev.Major = (temp>>2) &  0x3FFF;
297 	    temp = make_uint24(fhp[1], fhp[2], fhp[3]);
298 	    fsidp->Fsid_dev.Minor = temp & 0x3FFFF;
299 	    fsidp->fsid_code = make_uint32(fhp[4], fhp[5], fhp[6], fhp[7]);
300 
301 	    temp = make_uint32(fhp[12], fhp[13], fhp[14], fhp[15]);
302 	    *inop = temp;
303 
304 	    if (osnamep)
305 		*osnamep = "SUNOS5";
306 	    break;
307 
308 	case FHT_ULTRIX:
309 	    fsidp->fsid_code = 0;
310 	    fsidp->Fsid_dev.Minor = fhp[0];
311 	    fsidp->Fsid_dev.Major = fhp[1];
312 
313 	    temp = make_uint32(fhp[7], fhp[6], fhp[5], fhp[4]);
314 	    *inop = temp;
315 	    if (osnamep)
316 		*osnamep = "Ultrix";
317 	    break;
318 
319 	case FHT_VMSUCX:
320 	    /* No numeric file system ID, so hash on the device-name */
321 	    if (sizeof(*fsidp) >= 14) {
322 		if (sizeof(*fsidp) > 14)
323 		    memset((char *)fsidp, 0, sizeof(*fsidp));
324 		/* just use the whole thing */
325 		memcpy((char *)fsidp, (char *)fh, 14);
326 	    }
327 	    else {
328 		u_int32_t tempa[4];	/* at least 16 bytes, maybe more */
329 
330 		memset((char *)tempa, 0, sizeof(tempa));
331 		memcpy((char *)tempa, (char *)fh, 14); /* ensure alignment */
332 		fsidp->Fsid_dev.Minor = tempa[0] + (tempa[1]<<1);
333 		fsidp->Fsid_dev.Major = tempa[2] + (tempa[3]<<1);
334 		fsidp->fsid_code = 0;
335 	    }
336 
337 	    /* VMS file ID is: (RVN, FidHi, FidLo) */
338 	    *inop = make_uint32(fhp[26], fhp[27], fhp[23], fhp[22]);
339 
340 	    /* Caller must save (and null-terminate?) this value */
341 	    if (fsnamep)
342 		*fsnamep = (char *)&(fhp[1]);
343 
344 	    if (osnamep)
345 		*osnamep = "VMS";
346 	    break;
347 
348 	case FHT_AIX32:
349 	    fsidp->Fsid_dev.Minor = make_uint16(fhp[2], fhp[3]);
350 	    fsidp->Fsid_dev.Major = make_uint16(fhp[0], fhp[1]);
351 	    fsidp->fsid_code = make_uint32(fhp[4], fhp[5], fhp[6], fhp[7]);
352 
353 	    temp = make_uint32(fhp[12], fhp[13], fhp[14], fhp[15]);
354 	    *inop = temp;
355 
356 	    if (osnamep)
357 		*osnamep = "AIX32";
358 	    break;
359 
360 	case FHT_HPUX9:
361 	    fsidp->Fsid_dev.Major = fhp[0];
362 	    temp = make_uint24(fhp[1], fhp[2], fhp[3]);
363 	    fsidp->Fsid_dev.Minor = temp;
364 	    fsidp->fsid_code = make_uint32(fhp[4], fhp[5], fhp[6], fhp[7]);
365 
366 	    temp = make_uint32(fhp[12], fhp[13], fhp[14], fhp[15]);
367 	    *inop = temp;
368 
369 	    if (osnamep)
370 		*osnamep = "HPUX9";
371 	    break;
372 
373 	case FHT_UNKNOWN:
374 #ifdef DEBUG
375 	    {
376 		/* XXX debugging */
377 		int i;
378 		for (i = 0; i < 32; i++)
379 			(void)fprintf(stderr, "%x.", fhp[i]);
380 		(void)fprintf(stderr, "\n");
381 	    }
382 #endif
383 	    /* XXX for now, give "bogus" values to aid debugging */
384 	    fsidp->fsid_code = 0;
385 	    fsidp->Fsid_dev.Minor = 257;
386 	    fsidp->Fsid_dev.Major = 257;
387 	    *inop = 1;
388 
389 	    /* display will show this string instead of (257,257) */
390 	    if (fsnamep)
391 		*fsnamep = "Unknown";
392 
393 	    if (osnamep)
394 		*osnamep = "Unknown";
395 	    break;
396 
397 	}
398 }
399 
400 /*
401  * Is this a VMS UCX file handle?
402  *	Check for:
403  *	(1) leading code byte	[XXX not yet]
404  *	(2) followed by string of printing chars & spaces
405  *	(3) followed by string of nulls
406  */
407 static int
408 is_UCX(fhp)
409 unsigned char *fhp;
410 {
411 	register int i;
412 	int seen_null = 0;
413 
414 	for (i = 1; i < 14; i++) {
415 	    if (isprint(fhp[i])) {
416 		if (seen_null)
417 		   return(0);
418 		else
419 		   continue;
420 	    }
421 	    else if (fhp[i] == 0) {
422 		seen_null = 1;
423 		continue;
424 	    }
425 	    else
426 		return(0);
427 	}
428 
429 	return(1);
430 }
431