The Tcpdump Group git mirrors - tcpdump/blob - parsenfsfh.c

   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 <config.h>
  44
  45 #include "netdissect-stdinc.h"
  46
  47 #include <stdio.h>
  48 #include <string.h>
  49 #include <limits.h>
  50
  51 #include "netdissect-ctype.h"
  52
  53 #include "netdissect.h"
  54 #include "extract.h"
  55 #include "nfsfh.h"
  56
  57 /*
  58  * This routine attempts to parse a file handle (in network byte order),
  59  * using heuristics to guess what kind of format it is in.  See the
  60  * file "fhandle_layouts" for a detailed description of the various
  61  * patterns we know about.
  62  *
  63  * The file handle is parsed into our internal representation of a
  64  * file-system id, and an internal representation of an inode-number.
  65  */
  66
  67 #define FHT_UNKNOWN     0
  68 #define FHT_AUSPEX      1
  69 #define FHT_DECOSF      2
  70 #define FHT_IRIX4       3
  71 #define FHT_IRIX5       4
  72 #define FHT_SUNOS3      5
  73 #define FHT_SUNOS4      6
  74 #define FHT_ULTRIX      7
  75 #define FHT_VMSUCX      8
  76 #define FHT_SUNOS5      9
  77 #define FHT_AIX32       10
  78 #define FHT_HPUX9       11
  79 #define FHT_BSD44       12
  80
  81 static int is_UCX(netdissect_options *, const unsigned char *, u_int);
  82
  83 void
  84 Parse_fh(netdissect_options *ndo, const unsigned char *fh, u_int len,
  85          my_fsid *fsidp, uint32_t *inop,
  86          const char **osnamep, /* if non-NULL, return OS name here */
  87          const char **fsnamep, /* if non-NULL, return server fs name here (for VMS) */
  88          int ourself)   /* true if file handle was generated on this host */
  89 {
  90         const unsigned char *fhp = fh;
  91         uint32_t temp;
  92         int fhtype = FHT_UNKNOWN;
  93         u_int i;
  94
  95         /*
  96          * Require at least 16 bytes of file handle; it's variable-length
  97          * in NFSv3.  "len" is in units of 32-bit words, not bytes.
  98          */
  99         if (len < 16/4)
 100                 fhtype = FHT_UNKNOWN;
 101         else {
 102                 if (ourself) {
 103                     /* File handle generated on this host, no need for guessing */
 104 #if     defined(IRIX40)
 105                     fhtype = FHT_IRIX4;
 106 #endif
 107 #if     defined(IRIX50)
 108                     fhtype = FHT_IRIX5;
 109 #endif
 110 #if     defined(IRIX51)
 111                     fhtype = FHT_IRIX5;
 112 #endif
 113 #if     defined(SUNOS4)
 114                     fhtype = FHT_SUNOS4;
 115 #endif
 116 #if     defined(SUNOS5)
 117                     fhtype = FHT_SUNOS5;
 118 #endif
 119 #if     defined(ultrix)
 120                     fhtype = FHT_ULTRIX;
 121 #endif
 122 #if     defined(__osf__)
 123                     fhtype = FHT_DECOSF;
 124 #endif
 125 #if     defined(__NetBSD__) || defined(__FreeBSD__) || defined(__DragonFly__) \
 126      || defined(__OpenBSD__)
 127                     fhtype = FHT_BSD44;
 128 #endif
 129                 }
 130                 /*
 131                  * This is basically a big decision tree
 132                  */
 133                 else if ((GET_U_1(fhp) == 0) && (GET_U_1(fhp + 1) == 0)) {
 134                     /* bytes[0,1] == (0,0); rules out Ultrix, IRIX5, SUNOS5 */
 135                     /* probably rules out HP-UX, AIX unless they allow major=0 */
 136                     if ((GET_U_1(fhp + 2) == 0) && (GET_U_1(fhp + 3) == 0)) {
 137                         /* bytes[2,3] == (0,0); must be Auspex */
 138                         /* XXX or could be Ultrix+MASSBUS "hp" disk? */
 139                         fhtype = FHT_AUSPEX;
 140                     } else {
 141                         /*
 142                          * bytes[2,3] != (0,0); rules out Auspex, could be
 143                          * DECOSF, SUNOS4, or IRIX4
 144                          */
 145                         if ((GET_U_1(fhp + 4) != 0) && (GET_U_1(fhp + 5) == 0) &&
 146                                 (GET_U_1(fhp + 8) == 12) && (GET_U_1(fhp + 9) == 0)) {
 147                             /* seems to be DECOSF, with minor == 0 */
 148                             fhtype = FHT_DECOSF;
 149                         } else {
 150                             /* could be SUNOS4 or IRIX4 */
 151                             /* XXX the test of fhp[5] == 8 could be wrong */
 152                             if ((GET_U_1(fhp + 4) == 0) && (GET_U_1(fhp + 5) == 8) && (GET_U_1(fhp + 6) == 0) &&
 153                                 (GET_U_1(fhp + 7) == 0)) {
 154                                 /* looks like a length, not a file system typecode */
 155                                 fhtype = FHT_IRIX4;
 156                             } else {
 157                                 /* by elimination */
 158                                 fhtype = FHT_SUNOS4;
 159                             }
 160                         }
 161                     }
 162                 } else {
 163                     /*
 164                      * bytes[0,1] != (0,0); rules out Auspex, IRIX4, SUNOS4
 165                      * could be IRIX5, DECOSF, UCX, Ultrix, SUNOS5
 166                      * could be AIX, HP-UX
 167                      */
 168                     if ((GET_U_1(fhp + 2) == 0) && (GET_U_1(fhp + 3) == 0)) {
 169                         /*
 170                          * bytes[2,3] == (0,0); rules out OSF, probably not UCX
 171                          * (unless the exported device name is just one letter!),
 172                          * could be Ultrix, IRIX5, AIX, or SUNOS5
 173                          * might be HP-UX (depends on their values for minor devs)
 174                          */
 175                         if ((GET_U_1(fhp + 6) == 0) && (GET_U_1(fhp + 7) == 0)) {
 176                             fhtype = FHT_BSD44;
 177                         }
 178                         /*XXX we probably only need to test of these two bytes */
 179                         else if ((len >= 24/4) && (GET_U_1(fhp + 21) == 0) && (GET_U_1(fhp + 23) == 0)) {
 180                             fhtype = FHT_ULTRIX;
 181                         } else {
 182                             /* Could be SUNOS5/IRIX5, maybe AIX */
 183                             /* XXX no obvious difference between SUNOS5 and IRIX5 */
 184                             if (GET_U_1(fhp + 9) == 10)
 185                                 fhtype = FHT_SUNOS5;
 186                             /* XXX what about AIX? */
 187                         }
 188                     } else {
 189                         /*
 190                          * bytes[2,3] != (0,0); rules out Ultrix, could be
 191                          * DECOSF, SUNOS5, IRIX5, AIX, HP-UX, or UCX
 192                          */
 193                         if ((GET_U_1(fhp + 8) == 12) && (GET_U_1(fhp + 9) == 0)) {
 194                             fhtype = FHT_DECOSF;
 195                         } else if ((GET_U_1(fhp + 8) == 0) && (GET_U_1(fhp + 9) == 10)) {
 196                             /* could be SUNOS5/IRIX5, AIX, HP-UX */
 197                             if ((GET_U_1(fhp + 7) == 0) && (GET_U_1(fhp + 6) == 0) &&
 198                                 (GET_U_1(fhp + 5) == 0) && (GET_U_1(fhp + 4) == 0)) {
 199                                 /* XXX is this always true of HP-UX? */
 200                                 fhtype = FHT_HPUX9;
 201                             } else if (GET_U_1(fhp + 7) == 2) {
 202                                 /* This would be MNT_NFS on AIX, which is impossible */
 203                                 fhtype = FHT_SUNOS5;    /* or maybe IRIX5 */
 204                             } else {
 205                                 /*
 206                                  * XXX Could be SUNOS5/IRIX5 or AIX.  I don't
 207                                  * XXX see any way to disambiguate these, so
 208                                  * XXX I'm going with the more likely guess.
 209                                  * XXX Sorry, Big Blue.
 210                                  */
 211                                 fhtype = FHT_SUNOS5;    /* or maybe IRIX5 */
 212                             }
 213                         } else {
 214                             if (is_UCX(ndo, fhp, len)) {
 215                                 fhtype = FHT_VMSUCX;
 216                             } else {
 217                                 fhtype = FHT_UNKNOWN;
 218                             }
 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 = GET_U_1(fhp + 7);
 229             fsidp->Fsid_dev.Major = GET_U_1(fhp + 6);
 230             fsidp->fsid_code = 0;
 231
 232             *inop = GET_BE_U_4(fhp + 12);
 233
 234             if (osnamep)
 235                 *osnamep = "Auspex";
 236             break;
 237
 238         case FHT_BSD44:
 239             fsidp->Fsid_dev.Minor = GET_U_1(fhp);
 240             fsidp->Fsid_dev.Major = GET_U_1(fhp + 1);
 241             fsidp->fsid_code = 0;
 242
 243             *inop = GET_LE_U_4(fhp + 12);
 244
 245             if (osnamep)
 246                 *osnamep = "BSD 4.4";
 247             break;
 248
 249         case FHT_DECOSF:
 250             fsidp->fsid_code = GET_LE_U_4(fhp + 4);
 251                         /* XXX could ignore 3 high-order bytes */
 252
 253             temp = GET_LE_U_4(fhp);
 254             fsidp->Fsid_dev.Minor = temp & 0xFFFFF;
 255             fsidp->Fsid_dev.Major = (temp>>20) & 0xFFF;
 256
 257             *inop = GET_LE_U_4(fhp + 12);
 258             if (osnamep)
 259                 *osnamep = "OSF";
 260             break;
 261
 262         case FHT_IRIX4:
 263             fsidp->Fsid_dev.Minor = GET_U_1(fhp + 3);
 264             fsidp->Fsid_dev.Major = GET_U_1(fhp + 2);
 265             fsidp->fsid_code = 0;
 266
 267             *inop = GET_BE_U_4(fhp + 8);
 268
 269             if (osnamep)
 270                 *osnamep = "IRIX4";
 271             break;
 272
 273         case FHT_IRIX5:
 274             fsidp->Fsid_dev.Minor = GET_BE_U_2(fhp + 2);
 275             fsidp->Fsid_dev.Major = GET_BE_U_2(fhp);
 276             fsidp->fsid_code = GET_BE_U_4(fhp + 4);
 277
 278             *inop = GET_BE_U_4(fhp + 12);
 279
 280             if (osnamep)
 281                 *osnamep = "IRIX5";
 282             break;
 283
 284 #ifdef notdef
 285         case FHT_SUNOS3:
 286             /*
 287              * XXX - none of the heuristics above return this.
 288              * Are there any SunOS 3.x systems around to care about?
 289              */
 290             if (osnamep)
 291                 *osnamep = "SUNOS3";
 292             break;
 293 #endif
 294
 295         case FHT_SUNOS4:
 296             fsidp->Fsid_dev.Minor = GET_U_1(fhp + 3);
 297             fsidp->Fsid_dev.Major = GET_U_1(fhp + 2);
 298             fsidp->fsid_code = GET_BE_U_4(fhp + 4);
 299
 300             *inop = GET_BE_U_4(fhp + 12);
 301
 302             if (osnamep)
 303                 *osnamep = "SUNOS4";
 304             break;
 305
 306         case FHT_SUNOS5:
 307             temp = GET_BE_U_2(fhp);
 308             fsidp->Fsid_dev.Major = (temp>>2) &  0x3FFF;
 309             temp = GET_BE_U_3(fhp + 1);
 310             fsidp->Fsid_dev.Minor = temp & 0x3FFFF;
 311             fsidp->fsid_code = GET_BE_U_4(fhp + 4);
 312
 313             *inop = GET_BE_U_4(fhp + 12);
 314
 315             if (osnamep)
 316                 *osnamep = "SUNOS5";
 317             break;
 318
 319         case FHT_ULTRIX:
 320             fsidp->fsid_code = 0;
 321             fsidp->Fsid_dev.Minor = GET_U_1(fhp);
 322             fsidp->Fsid_dev.Major = GET_U_1(fhp + 1);
 323
 324             temp = GET_LE_U_4(fhp + 4);
 325             *inop = temp;
 326             if (osnamep)
 327                 *osnamep = "Ultrix";
 328             break;
 329
 330         case FHT_VMSUCX:
 331             /* No numeric file system ID, so hash on the device-name */
 332             memset((char *)fsidp, 0, sizeof(*fsidp));
 333             /* just use the whole thing */
 334             memcpy((char *)fsidp, (const char *)fh, 14);
 335
 336             /* VMS file ID is: (RVN, FidHi, FidLo) */
 337             *inop = (((uint32_t) GET_U_1(fhp + 26)) << 24) |
 338                     (((uint32_t) GET_U_1(fhp + 27)) << 16) |
 339                     (GET_LE_U_2(fhp + 22) << 0);
 340
 341             /* Caller must save (and null-terminate?) this value */
 342             if (fsnamep)
 343                 *fsnamep = (const char *)(fhp + 1);
 344
 345             if (osnamep)
 346                 *osnamep = "VMS";
 347             break;
 348
 349         case FHT_AIX32:
 350             fsidp->Fsid_dev.Minor = GET_BE_U_2(fhp + 2);
 351             fsidp->Fsid_dev.Major = GET_BE_U_2(fhp);
 352             fsidp->fsid_code = GET_BE_U_4(fhp + 4);
 353
 354             *inop = GET_BE_U_4(fhp + 12);
 355
 356             if (osnamep)
 357                 *osnamep = "AIX32";
 358             break;
 359
 360         case FHT_HPUX9:
 361             fsidp->Fsid_dev.Major = GET_U_1(fhp);
 362             temp = GET_BE_U_3(fhp + 1);
 363             fsidp->Fsid_dev.Minor = temp;
 364             fsidp->fsid_code = GET_BE_U_4(fhp + 4);
 365
 366             *inop = GET_BE_U_4(fhp + 12);
 367
 368             if (osnamep)
 369                 *osnamep = "HPUX9";
 370             break;
 371
 372         case FHT_UNKNOWN:
 373 #ifdef DEBUG
 374             /* XXX debugging */
 375             for (i = 0; i < len*4; i++)
 376                 (void)fprintf(stderr, "%x.", GET_U_1(fhp + i));
 377             (void)fprintf(stderr, "\n");
 378 #endif
 379             /* Save the actual handle, so it can be display with -u */
 380             /* XXX really ? When -u is used this function is not called */
 381             for (i = 0; i < len*4 && i*2 < sizeof(fsidp->Opaque_Handle) - 1; i++)
 382                 (void)snprintf(&(fsidp->Opaque_Handle[i*2]), 3, "%.2X",
 383                                GET_U_1(fhp + i));
 384             fsidp->Opaque_Handle[i*2] = '\0';
 385
 386             /* XXX for now, give "bogus" values to aid debugging */
 387             fsidp->fsid_code = 0;
 388             fsidp->Fsid_dev.Minor = UINT_MAX;
 389             fsidp->Fsid_dev.Major = UINT_MAX;
 390             *inop = 1;
 391
 392             /* display will show this string instead of (UINT_MAX,UINT_MAX) */
 393             /* XXX really ? */
 394             if (fsnamep)
 395                 *fsnamep = "Unknown";
 396
 397             if (osnamep)
 398                 *osnamep = "Unknown";
 399             break;
 400
 401         }
 402 }
 403
 404 /*
 405  * Is this a VMS UCX file handle?
 406  *      Check for:
 407  *      (1) leading code byte   [XXX not yet]
 408  *      (2) followed by string of printing chars & spaces
 409  *      (3) followed by string of nulls
 410  */
 411 static int
 412 is_UCX(netdissect_options *ndo, const unsigned char *fhp, u_int len)
 413 {
 414         u_int i;
 415         int seen_null = 0;
 416
 417         /*
 418          * Require at least 28 bytes of file handle; it's variable-length
 419          * in NFSv3.  "len" is in units of 32-bit words, not bytes.
 420          */
 421         if (len < 28/4)
 422                 return(0);
 423
 424         for (i = 1; i < 14; i++) {
 425             if (ND_ASCII_ISPRINT(GET_U_1(fhp + i))) {
 426                 if (seen_null)
 427                    return(0);
 428                 else
 429                    continue;
 430             } else if (GET_U_1(fhp + i) == 0) {
 431                 seen_null = 1;
 432                 continue;
 433             } else
 434                 return(0);
 435         }
 436
 437         return(1);
 438 }