xref: /freebsd/contrib/tcpdump/parsenfsfh.c (revision 2ebf6c05136945eb89ae7597c7daaf1e1cfa04e2)
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 
10 #ifndef lint
11 static const char rcsid[] =
12     "@(#) $Header: parsenfsfh.c,v 1.12 96/12/10 23:25:50 leres Exp $ (LBL)";
13 #endif
14 
15 #include <sys/types.h>
16 #include <sys/time.h>
17 
18 #include <ctype.h>
19 #include <memory.h>
20 #include <stdio.h>
21 #include <string.h>
22 
23 #include "interface.h"
24 #include "nfsfh.h"
25 
26 /*
27  * This routine attempts to parse a file handle (in network byte order),
28  * using heuristics to guess what kind of format it is in.  See the
29  * file "fhandle_layouts" for a detailed description of the various
30  * patterns we know about.
31  *
32  * The file handle is parsed into our internal representation of a
33  * file-system id, and an internal representation of an inode-number.
34  */
35 
36 #define	FHT_UNKNOWN	0
37 #define	FHT_AUSPEX	1
38 #define	FHT_DECOSF	2
39 #define	FHT_IRIX4	3
40 #define	FHT_IRIX5	4
41 #define	FHT_SUNOS3	5
42 #define	FHT_SUNOS4	6
43 #define	FHT_ULTRIX	7
44 #define	FHT_VMSUCX	8
45 #define	FHT_SUNOS5	9
46 #define	FHT_AIX32	10
47 #define	FHT_HPUX9	11
48 
49 #ifdef	ultrix
50 /* Nasty hack to keep the Ultrix C compiler from emitting bogus warnings */
51 #define	XFF(x)	((u_int32_t)(x))
52 #else
53 #define	XFF(x)	(x)
54 #endif
55 
56 #define	make_uint32(msb,b,c,lsb)\
57 	(XFF(lsb) + (XFF(c)<<8) + (XFF(b)<<16) + (XFF(msb)<<24))
58 
59 #define	make_uint24(msb,b, lsb)\
60 	(XFF(lsb) + (XFF(b)<<8) + (XFF(msb)<<16))
61 
62 #define	make_uint16(msb,lsb)\
63 	(XFF(lsb) + (XFF(msb)<<8))
64 
65 #ifdef	__alpha
66 	/* or other 64-bit systems */
67 #define	make_uint48(msb,b,c,d,e,lsb)\
68 	((lsb) + ((e)<<8) + ((d)<<16) + ((c)<<24) + ((b)<<32) + ((msb)<<40))
69 #else
70 	/* on 32-bit systems ignore high-order bits */
71 #define	make_uint48(msb,b,c,d,e,lsb)\
72 	((lsb) + ((e)<<8) + ((d)<<16) + ((c)<<24))
73 #endif
74 
75 static int is_UCX(unsigned char *);
76 
77 void
78 Parse_fh(fh, len, fsidp, inop, osnamep, fsnamep, ourself)
79 register caddr_t *fh;
80 int len;
81 my_fsid *fsidp;
82 ino_t *inop;
83 char **osnamep;		/* if non-NULL, return OS name here */
84 char **fsnamep;		/* if non-NULL, return server fs name here (for VMS) */
85 int ourself;		/* true if file handle was generated on this host */
86 {
87 	register unsigned char *fhp = (unsigned char *)fh;
88 	u_int32_t temp;
89 	int fhtype = FHT_UNKNOWN;
90 
91 	if (ourself) {
92 	    /* File handle generated on this host, no need for guessing */
93 #if	defined(IRIX40)
94 	    fhtype = FHT_IRIX4;
95 #endif
96 #if	defined(IRIX50)
97 	    fhtype = FHT_IRIX5;
98 #endif
99 #if	defined(IRIX51)
100 	    fhtype = FHT_IRIX5;
101 #endif
102 #if	defined(SUNOS4)
103 	    fhtype = FHT_SUNOS4;
104 #endif
105 #if	defined(SUNOS5)
106 	    fhtype = FHT_SUNOS5;
107 #endif
108 #if	defined(ultrix)
109 	    fhtype = FHT_ULTRIX;
110 #endif
111 #if	defined(__osf__)
112 	    fhtype = FHT_DECOSF;
113 #endif
114 	}
115 	/*
116 	 * This is basically a big decision tree
117 	 */
118 	else if ((fhp[0] == 0) && (fhp[1] == 0)) {
119 	    /* bytes[0,1] == (0,0); rules out Ultrix, IRIX5, SUNOS5 */
120 	    /* probably rules out HP-UX, AIX unless they allow major=0 */
121 	    if ((fhp[2] == 0) && (fhp[3] == 0)) {
122 		/* bytes[2,3] == (0,0); must be Auspex */
123 		/* XXX or could be Ultrix+MASSBUS "hp" disk? */
124 		fhtype = FHT_AUSPEX;
125 	    }
126 	    else {
127 		/*
128 		 * bytes[2,3] != (0,0); rules out Auspex, could be
129 		 * DECOSF, SUNOS4, or IRIX4
130 		 */
131 		if ((fhp[4] != 0) && (fhp[5] == 0) &&
132 			(fhp[8] == 12) && (fhp[9] == 0)) {
133 		    /* seems to be DECOSF, with minor == 0 */
134 		    fhtype = FHT_DECOSF;
135 		}
136 		else {
137 		    /* could be SUNOS4 or IRIX4 */
138 		    /* XXX the test of fhp[5] == 8 could be wrong */
139 		    if ((fhp[4] == 0) && (fhp[5] == 8) && (fhp[6] == 0) &&
140 			(fhp[7] == 0)) {
141 			/* looks like a length, not a file system typecode */
142 			fhtype = FHT_IRIX4;
143 		    }
144 		    else {
145 			/* by elimination */
146 			fhtype = FHT_SUNOS4;
147 		    }
148 		}
149 	    }
150 	}
151 	else {
152 	    /*
153 	     * bytes[0,1] != (0,0); rules out Auspex, IRIX4, SUNOS4
154 	     * could be IRIX5, DECOSF, UCX, Ultrix, SUNOS5
155 	     * could be AIX, HP-UX
156 	     */
157 	    if ((fhp[2] == 0) && (fhp[3] == 0)) {
158 		/*
159 		 * bytes[2,3] == (0,0); rules out OSF, probably not UCX
160 		 * (unless the exported device name is just one letter!),
161 		 * could be Ultrix, IRIX5, AIX, or SUNOS5
162 		 * might be HP-UX (depends on their values for minor devs)
163 		 */
164 		/*XXX we probably only need to test of these two bytes */
165 		if ((fhp[21] == 0) && (fhp[23] == 0)) {
166 		    fhtype = FHT_ULTRIX;
167 		}
168 		else {
169 		    /* Could be SUNOS5/IRIX5, maybe AIX */
170 		    /* XXX no obvious difference between SUNOS5 and IRIX5 */
171 		    if (fhp[9] == 10)
172 			fhtype = FHT_SUNOS5;
173 		    /* XXX what about AIX? */
174 		}
175 	    }
176 	    else {
177 		/*
178 		 * bytes[2,3] != (0,0); rules out Ultrix, could be
179 		 * DECOSF, SUNOS5, IRIX5, AIX, HP-UX, or UCX
180 		 */
181 		if ((fhp[8] == 12) && (fhp[9] == 0)) {
182 		    fhtype = FHT_DECOSF;
183 		}
184 		else if ((fhp[8] == 0) && (fhp[9] == 10)) {
185 		    /* could be SUNOS5/IRIX5, AIX, HP-UX */
186 		    if ((fhp[7] == 0) && (fhp[6] == 0) &&
187 			(fhp[5] == 0) && (fhp[4] == 0)) {
188 			/* XXX is this always true of HP-UX? */
189 			fhtype = FHT_HPUX9;
190 		    }
191 		    else if (fhp[7] == 2) {
192 			/* This would be MNT_NFS on AIX, which is impossible */
193 			fhtype = FHT_SUNOS5;	/* or maybe IRIX5 */
194 		    }
195 		    else {
196 			/*
197 			 * XXX Could be SUNOS5/IRIX5 or AIX.  I don't
198 			 * XXX see any way to disambiguate these, so
199 			 * XXX I'm going with the more likely guess.
200 			 * XXX Sorry, Big Blue.
201 			 */
202 			fhtype = FHT_SUNOS5;	/* or maybe IRIX5 */
203 		    }
204 	        }
205 		else {
206 		    if (is_UCX(fhp)) {
207 			fhtype = FHT_VMSUCX;
208 		    }
209 		    else {
210 			fhtype = FHT_UNKNOWN;
211 		    }
212 		}
213 	    }
214 	}
215 
216 	/* XXX still needs to handle SUNOS3 */
217 
218 	switch (fhtype) {
219 	case FHT_AUSPEX:
220 	    fsidp->Fsid_dev.Minor = fhp[7];
221 	    fsidp->Fsid_dev.Major = fhp[6];
222 	    fsidp->fsid_code = 0;
223 
224 	    temp = make_uint32(fhp[12], fhp[13], fhp[14], fhp[15]);
225 	    *inop = temp;
226 
227 	    if (osnamep)
228 		*osnamep = "Auspex";
229 	    break;
230 
231 	case FHT_DECOSF:
232 	    fsidp->fsid_code = make_uint32(fhp[7], fhp[6], fhp[5], fhp[4]);
233 			/* XXX could ignore 3 high-order bytes */
234 
235 	    temp = make_uint32(fhp[3], fhp[2], fhp[1], fhp[0]);
236 	    fsidp->Fsid_dev.Minor = temp & 0xFFFFF;
237 	    fsidp->Fsid_dev.Major = (temp>>20) & 0xFFF;
238 
239 	    temp = make_uint32(fhp[15], fhp[14], fhp[13], fhp[12]);
240 	    *inop = temp;
241 	    if (osnamep)
242 		*osnamep = "OSF";
243 	    break;
244 
245 	case FHT_IRIX4:
246 	    fsidp->Fsid_dev.Minor = fhp[3];
247 	    fsidp->Fsid_dev.Major = fhp[2];
248 	    fsidp->fsid_code = 0;
249 
250 	    temp = make_uint32(fhp[8], fhp[9], fhp[10], fhp[11]);
251 	    *inop = temp;
252 
253 	    if (osnamep)
254 		*osnamep = "IRIX4";
255 	    break;
256 
257 	case FHT_IRIX5:
258 	    fsidp->Fsid_dev.Minor = make_uint16(fhp[2], fhp[3]);
259 	    fsidp->Fsid_dev.Major = make_uint16(fhp[0], fhp[1]);
260 	    fsidp->fsid_code = make_uint32(fhp[4], fhp[5], fhp[6], fhp[7]);
261 
262 	    temp = make_uint32(fhp[12], fhp[13], fhp[14], fhp[15]);
263 	    *inop = temp;
264 
265 	    if (osnamep)
266 		*osnamep = "IRIX5";
267 	    break;
268 
269 	case FHT_SUNOS3:
270 	    if (osnamep)
271 		*osnamep = "SUNOS3";
272 	    break;
273 
274 	case FHT_SUNOS4:
275 	    fsidp->Fsid_dev.Minor = fhp[3];
276 	    fsidp->Fsid_dev.Major = fhp[2];
277 	    fsidp->fsid_code = make_uint32(fhp[4], fhp[5], fhp[6], fhp[7]);
278 
279 	    temp = make_uint32(fhp[12], fhp[13], fhp[14], fhp[15]);
280 	    *inop = temp;
281 
282 	    if (osnamep)
283 		*osnamep = "SUNOS4";
284 	    break;
285 
286 	case FHT_SUNOS5:
287 	    temp = make_uint16(fhp[0], fhp[1]);
288 	    fsidp->Fsid_dev.Major = (temp>>2) &  0x3FFF;
289 	    temp = make_uint24(fhp[1], fhp[2], fhp[3]);
290 	    fsidp->Fsid_dev.Minor = temp & 0x3FFFF;
291 	    fsidp->fsid_code = make_uint32(fhp[4], fhp[5], fhp[6], fhp[7]);
292 
293 	    temp = make_uint32(fhp[12], fhp[13], fhp[14], fhp[15]);
294 	    *inop = temp;
295 
296 	    if (osnamep)
297 		*osnamep = "SUNOS5";
298 	    break;
299 
300 	case FHT_ULTRIX:
301 	    fsidp->fsid_code = 0;
302 	    fsidp->Fsid_dev.Minor = fhp[0];
303 	    fsidp->Fsid_dev.Major = fhp[1];
304 
305 	    temp = make_uint32(fhp[7], fhp[6], fhp[5], fhp[4]);
306 	    *inop = temp;
307 	    if (osnamep)
308 		*osnamep = "Ultrix";
309 	    break;
310 
311 	case FHT_VMSUCX:
312 	    /* No numeric file system ID, so hash on the device-name */
313 	    if (sizeof(*fsidp) >= 14) {
314 		if (sizeof(*fsidp) > 14)
315 		    memset((char *)fsidp, 0, sizeof(*fsidp));
316 		memcpy((char *)fsidp, fh, 14);	/* just use the whole thing */
317 	    }
318 	    else {
319 		u_int32_t tempa[4];	/* at least 16 bytes, maybe more */
320 
321 		memset((char *)tempa, 0, sizeof(tempa));
322 		memcpy((char *)tempa, fh, 14);	/* ensure alignment */
323 		fsidp->Fsid_dev.Minor = tempa[0] + (tempa[1]<<1);
324 		fsidp->Fsid_dev.Major = tempa[2] + (tempa[3]<<1);
325 		fsidp->fsid_code = 0;
326 	    }
327 
328 	    /* VMS file ID is: (RVN, FidHi, FidLo) */
329 	    *inop = make_uint32(fhp[26], fhp[27], fhp[23], fhp[22]);
330 
331 	    /* Caller must save (and null-terminate?) this value */
332 	    if (fsnamep)
333 		*fsnamep = (char *)&(fhp[1]);
334 
335 	    if (osnamep)
336 		*osnamep = "VMS";
337 	    break;
338 
339 	case FHT_AIX32:
340 	    fsidp->Fsid_dev.Minor = make_uint16(fhp[2], fhp[3]);
341 	    fsidp->Fsid_dev.Major = make_uint16(fhp[0], fhp[1]);
342 	    fsidp->fsid_code = make_uint32(fhp[4], fhp[5], fhp[6], fhp[7]);
343 
344 	    temp = make_uint32(fhp[12], fhp[13], fhp[14], fhp[15]);
345 	    *inop = temp;
346 
347 	    if (osnamep)
348 		*osnamep = "AIX32";
349 	    break;
350 
351 	case FHT_HPUX9:
352 	    fsidp->Fsid_dev.Major = fhp[0];
353 	    temp = make_uint24(fhp[1], fhp[2], fhp[3]);
354 	    fsidp->Fsid_dev.Minor = temp;
355 	    fsidp->fsid_code = make_uint32(fhp[4], fhp[5], fhp[6], fhp[7]);
356 
357 	    temp = make_uint32(fhp[12], fhp[13], fhp[14], fhp[15]);
358 	    *inop = temp;
359 
360 	    if (osnamep)
361 		*osnamep = "HPUX9";
362 	    break;
363 
364 	case FHT_UNKNOWN:
365 #ifdef DEBUG
366 	    {
367 		/* XXX debugging */
368 		int i;
369 		for (i = 0; i < 32; i++)
370 			(void)fprintf(stderr, "%x.", fhp[i]);
371 		(void)fprintf(stderr, "\n");
372 	    }
373 #endif
374 	    /* XXX for now, give "bogus" values to aid debugging */
375 	    fsidp->fsid_code = 0;
376 	    fsidp->Fsid_dev.Minor = 257;
377 	    fsidp->Fsid_dev.Major = 257;
378 	    *inop = 1;
379 
380 	    /* display will show this string instead of (257,257) */
381 	    if (fsnamep)
382 		*fsnamep = "Unknown";
383 
384 	    if (osnamep)
385 		*osnamep = "Unknown";
386 	    break;
387 
388 	}
389 }
390 
391 /*
392  * Is this a VMS UCX file handle?
393  *	Check for:
394  *	(1) leading code byte	[XXX not yet]
395  *	(2) followed by string of printing chars & spaces
396  *	(3) followed by string of nulls
397  */
398 static int
399 is_UCX(fhp)
400 unsigned char *fhp;
401 {
402 	register int i;
403 	int seen_null = 0;
404 
405 	for (i = 1; i < 14; i++) {
406 	    if (isprint(fhp[i])) {
407 		if (seen_null)
408 		   return(0);
409 		else
410 		   continue;
411 	    }
412 	    else if (fhp[i] == 0) {
413 		seen_null = 1;
414 		continue;
415 	    }
416 	    else
417 		return(0);
418 	}
419 
420 	return(1);
421 }
422