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 #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
  82 static int is_UCX(netdissect_options *, const unsigned char *, u_int);
  83
  84 void
  85 Parse_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  */
 433 static int
 434 is_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 }