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.h"
  53 #include "extract.h"
  54 #include "nfsfh.h"
  55
  56 /*
  57  * This routine attempts to parse a file handle (in network byte order),
  58  * using heuristics to guess what kind of format it is in.  See the
  59  * file "fhandle_layouts" for a detailed description of the various
  60  * patterns we know about.
  61  *
  62  * The file handle is parsed into our internal representation of a
  63  * file-system id, and an internal representation of an inode-number.
  64  */
  65
  66 #define FHT_UNKNOWN     0
  67 #define FHT_AUSPEX      1
  68 #define FHT_DECOSF      2
  69 #define FHT_IRIX4       3
  70 #define FHT_IRIX5       4
  71 #define FHT_SUNOS3      5
  72 #define FHT_SUNOS4      6
  73 #define FHT_ULTRIX      7
  74 #define FHT_VMSUCX      8
  75 #define FHT_SUNOS5      9
  76 #define FHT_AIX32       10
  77 #define FHT_HPUX9       11
  78 #define FHT_BSD44       12
  79
  80 static int is_UCX(const unsigned char *, u_int);
  81
  82 void
  83 Parse_fh(const unsigned char *fh, u_int len, my_fsid *fsidp,
  84          uint32_t *inop,
  85          const char **osnamep, /* if non-NULL, return OS name here */
  86          const char **fsnamep, /* if non-NULL, return server fs name here (for VMS) */
  87          int ourself)   /* true if file handle was generated on this host */
  88 {
  89         const unsigned char *fhp = fh;
  90         uint32_t temp;
  91         int fhtype = FHT_UNKNOWN;
  92         u_int i;
  93
  94         /*
  95          * Require at least 16 bytes of file handle; it's variable-length
  96          * in NFSv3.  "len" is in units of 32-bit words, not bytes.
  97          */
  98         if (len < 16/4)
  99                 fhtype = FHT_UNKNOWN;
 100         else {
 101                 if (ourself) {
 102                     /* File handle generated on this host, no need for guessing */
 103 #if     defined(IRIX40)
 104                     fhtype = FHT_IRIX4;
 105 #endif
 106 #if     defined(IRIX50)
 107                     fhtype = FHT_IRIX5;
 108 #endif
 109 #if     defined(IRIX51)
 110                     fhtype = FHT_IRIX5;
 111 #endif
 112 #if     defined(SUNOS4)
 113                     fhtype = FHT_SUNOS4;
 114 #endif
 115 #if     defined(SUNOS5)
 116                     fhtype = FHT_SUNOS5;
 117 #endif
 118 #if     defined(ultrix)
 119                     fhtype = FHT_ULTRIX;
 120 #endif
 121 #if     defined(__osf__)
 122                     fhtype = FHT_DECOSF;
 123 #endif
 124 #if     defined(__NetBSD__) || defined(__FreeBSD__) || defined(__DragonFly__) \
 125      || defined(__OpenBSD__)
 126                     fhtype = FHT_BSD44;
 127 #endif
 128                 }
 129                 /*
 130                  * This is basically a big decision tree
 131                  */
 132                 else if ((EXTRACT_U_1(fhp) == 0) && (EXTRACT_U_1(fhp + 1) == 0)) {
 133                     /* bytes[0,1] == (0,0); rules out Ultrix, IRIX5, SUNOS5 */
 134                     /* probably rules out HP-UX, AIX unless they allow major=0 */
 135                     if ((EXTRACT_U_1(fhp + 2) == 0) && (EXTRACT_U_1(fhp + 3) == 0)) {
 136                         /* bytes[2,3] == (0,0); must be Auspex */
 137                         /* XXX or could be Ultrix+MASSBUS "hp" disk? */
 138                         fhtype = FHT_AUSPEX;
 139                     }
 140                     else {
 141                         /*
 142                          * bytes[2,3] != (0,0); rules out Auspex, could be
 143                          * DECOSF, SUNOS4, or IRIX4
 144                          */
 145                         if ((EXTRACT_U_1(fhp + 4) != 0) && (EXTRACT_U_1(fhp + 5) == 0) &&
 146                                 (EXTRACT_U_1(fhp + 8) == 12) && (EXTRACT_U_1(fhp + 9) == 0)) {
 147                             /* seems to be DECOSF, with minor == 0 */
 148                             fhtype = FHT_DECOSF;
 149                         }
 150                         else {
 151                             /* could be SUNOS4 or IRIX4 */
 152                             /* XXX the test of fhp[5] == 8 could be wrong */
 153                             if ((EXTRACT_U_1(fhp + 4) == 0) && (EXTRACT_U_1(fhp + 5) == 8) && (EXTRACT_U_1(fhp + 6) == 0) &&
 154                                 (EXTRACT_U_1(fhp + 7) == 0)) {
 155                                 /* looks like a length, not a file system typecode */
 156                                 fhtype = FHT_IRIX4;
 157                             }
 158                             else {
 159                                 /* by elimination */
 160                                 fhtype = FHT_SUNOS4;
 161                             }
 162                         }
 163                     }
 164                 }
 165                 else {
 166                     /*
 167                      * bytes[0,1] != (0,0); rules out Auspex, IRIX4, SUNOS4
 168                      * could be IRIX5, DECOSF, UCX, Ultrix, SUNOS5
 169                      * could be AIX, HP-UX
 170                      */
 171                     if ((EXTRACT_U_1(fhp + 2) == 0) && (EXTRACT_U_1(fhp + 3) == 0)) {
 172                         /*
 173                          * bytes[2,3] == (0,0); rules out OSF, probably not UCX
 174                          * (unless the exported device name is just one letter!),
 175                          * could be Ultrix, IRIX5, AIX, or SUNOS5
 176                          * might be HP-UX (depends on their values for minor devs)
 177                          */
 178                         if ((EXTRACT_U_1(fhp + 6) == 0) && (EXTRACT_U_1(fhp + 7) == 0)) {
 179                             fhtype = FHT_BSD44;
 180                         }
 181                         /*XXX we probably only need to test of these two bytes */
 182                         else if ((len >= 24/4) && (EXTRACT_U_1(fhp + 21) == 0) && (EXTRACT_U_1(fhp + 23) == 0)) {
 183                             fhtype = FHT_ULTRIX;
 184                         }
 185                         else {
 186                             /* Could be SUNOS5/IRIX5, maybe AIX */
 187                             /* XXX no obvious difference between SUNOS5 and IRIX5 */
 188                             if (EXTRACT_U_1(fhp + 9) == 10)
 189                                 fhtype = FHT_SUNOS5;
 190                             /* XXX what about AIX? */
 191                         }
 192                     }
 193                     else {
 194                         /*
 195                          * bytes[2,3] != (0,0); rules out Ultrix, could be
 196                          * DECOSF, SUNOS5, IRIX5, AIX, HP-UX, or UCX
 197                          */
 198                         if ((EXTRACT_U_1(fhp + 8) == 12) && (EXTRACT_U_1(fhp + 9) == 0)) {
 199                             fhtype = FHT_DECOSF;
 200                         }
 201                         else if ((EXTRACT_U_1(fhp + 8) == 0) && (EXTRACT_U_1(fhp + 9) == 10)) {
 202                             /* could be SUNOS5/IRIX5, AIX, HP-UX */
 203                             if ((EXTRACT_U_1(fhp + 7) == 0) && (EXTRACT_U_1(fhp + 6) == 0) &&
 204                                 (EXTRACT_U_1(fhp + 5) == 0) && (EXTRACT_U_1(fhp + 4) == 0)) {
 205                                 /* XXX is this always true of HP-UX? */
 206                                 fhtype = FHT_HPUX9;
 207                             }
 208                             else if (EXTRACT_U_1(fhp + 7) == 2) {
 209                                 /* This would be MNT_NFS on AIX, which is impossible */
 210                                 fhtype = FHT_SUNOS5;    /* or maybe IRIX5 */
 211                             }
 212                             else {
 213                                 /*
 214                                  * XXX Could be SUNOS5/IRIX5 or AIX.  I don't
 215                                  * XXX see any way to disambiguate these, so
 216                                  * XXX I'm going with the more likely guess.
 217                                  * XXX Sorry, Big Blue.
 218                                  */
 219                                 fhtype = FHT_SUNOS5;    /* or maybe IRIX5 */
 220                             }
 221                         }
 222                         else {
 223                             if (is_UCX(fhp, len)) {
 224                                 fhtype = FHT_VMSUCX;
 225                             }
 226                             else {
 227                                 fhtype = FHT_UNKNOWN;
 228                             }
 229                         }
 230                     }
 231                 }
 232         }
 233
 234         /* XXX still needs to handle SUNOS3 */
 235
 236         switch (fhtype) {
 237         case FHT_AUSPEX:
 238             fsidp->Fsid_dev.Minor = EXTRACT_U_1(fhp + 7);
 239             fsidp->Fsid_dev.Major = EXTRACT_U_1(fhp + 6);
 240             fsidp->fsid_code = 0;
 241
 242             *inop = EXTRACT_BE_U_4(fhp + 12);
 243
 244             if (osnamep)
 245                 *osnamep = "Auspex";
 246             break;
 247
 248         case FHT_BSD44:
 249             fsidp->Fsid_dev.Minor = EXTRACT_U_1(fhp);
 250             fsidp->Fsid_dev.Major = EXTRACT_U_1(fhp + 1);
 251             fsidp->fsid_code = 0;
 252
 253             *inop = EXTRACT_LE_U_4(fhp + 12);
 254
 255             if (osnamep)
 256                 *osnamep = "BSD 4.4";
 257             break;
 258
 259         case FHT_DECOSF:
 260             fsidp->fsid_code = EXTRACT_LE_U_4(fhp + 4);
 261                         /* XXX could ignore 3 high-order bytes */
 262
 263             temp = EXTRACT_LE_U_4(fhp);
 264             fsidp->Fsid_dev.Minor = temp & 0xFFFFF;
 265             fsidp->Fsid_dev.Major = (temp>>20) & 0xFFF;
 266
 267             *inop = EXTRACT_LE_U_4(fhp + 12);
 268             if (osnamep)
 269                 *osnamep = "OSF";
 270             break;
 271
 272         case FHT_IRIX4:
 273             fsidp->Fsid_dev.Minor = EXTRACT_U_1(fhp + 3);
 274             fsidp->Fsid_dev.Major = EXTRACT_U_1(fhp + 2);
 275             fsidp->fsid_code = 0;
 276
 277             *inop = EXTRACT_BE_U_4(fhp + 8);
 278
 279             if (osnamep)
 280                 *osnamep = "IRIX4";
 281             break;
 282
 283         case FHT_IRIX5:
 284             fsidp->Fsid_dev.Minor = EXTRACT_BE_U_2(fhp + 2);
 285             fsidp->Fsid_dev.Major = EXTRACT_BE_U_2(fhp);
 286             fsidp->fsid_code = EXTRACT_BE_U_4(fhp + 4);
 287
 288             *inop = EXTRACT_BE_U_4(fhp + 12);
 289
 290             if (osnamep)
 291                 *osnamep = "IRIX5";
 292             break;
 293
 294 #ifdef notdef
 295         case FHT_SUNOS3:
 296             /*
 297              * XXX - none of the heuristics above return this.
 298              * Are there any SunOS 3.x systems around to care about?
 299              */
 300             if (osnamep)
 301                 *osnamep = "SUNOS3";
 302             break;
 303 #endif
 304
 305         case FHT_SUNOS4:
 306             fsidp->Fsid_dev.Minor = EXTRACT_U_1(fhp + 3);
 307             fsidp->Fsid_dev.Major = EXTRACT_U_1(fhp + 2);
 308             fsidp->fsid_code = EXTRACT_BE_U_4(fhp + 4);
 309
 310             *inop = EXTRACT_BE_U_4(fhp + 12);
 311
 312             if (osnamep)
 313                 *osnamep = "SUNOS4";
 314             break;
 315
 316         case FHT_SUNOS5:
 317             temp = EXTRACT_BE_U_2(fhp);
 318             fsidp->Fsid_dev.Major = (temp>>2) &  0x3FFF;
 319             temp = EXTRACT_BE_U_3(fhp + 1);
 320             fsidp->Fsid_dev.Minor = temp & 0x3FFFF;
 321             fsidp->fsid_code = EXTRACT_BE_U_4(fhp + 4);
 322
 323             *inop = EXTRACT_BE_U_4(fhp + 12);
 324
 325             if (osnamep)
 326                 *osnamep = "SUNOS5";
 327             break;
 328
 329         case FHT_ULTRIX:
 330             fsidp->fsid_code = 0;
 331             fsidp->Fsid_dev.Minor = EXTRACT_U_1(fhp);
 332             fsidp->Fsid_dev.Major = EXTRACT_U_1(fhp + 1);
 333
 334             temp = EXTRACT_LE_U_4(fhp + 4);
 335             *inop = temp;
 336             if (osnamep)
 337                 *osnamep = "Ultrix";
 338             break;
 339
 340         case FHT_VMSUCX:
 341             /* No numeric file system ID, so hash on the device-name */
 342             if (sizeof(*fsidp) >= 14) {
 343                 if (sizeof(*fsidp) > 14)
 344                     memset((char *)fsidp, 0, sizeof(*fsidp));
 345                 /* just use the whole thing */
 346                 memcpy((char *)fsidp, (const char *)fh, 14);
 347             }
 348             else {
 349                 uint32_t tempa[4];      /* at least 16 bytes, maybe more */
 350
 351                 memset((char *)tempa, 0, sizeof(tempa));
 352                 memcpy((char *)tempa, (const char *)fh, 14); /* ensure alignment */
 353                 fsidp->Fsid_dev.Minor = tempa[0] + (tempa[1]<<1);
 354                 fsidp->Fsid_dev.Major = tempa[2] + (tempa[3]<<1);
 355                 fsidp->fsid_code = 0;
 356             }
 357
 358             /* VMS file ID is: (RVN, FidHi, FidLo) */
 359             *inop = (((uint32_t)EXTRACT_U_1(fhp + 26)) << 24) |
 360                     (((uint32_t)EXTRACT_U_1(fhp + 27)) << 16) |
 361                     (EXTRACT_LE_U_2(fhp + 22) << 0);
 362
 363             /* Caller must save (and null-terminate?) this value */
 364             if (fsnamep)
 365                 *fsnamep = (const char *)(fhp + 1);
 366
 367             if (osnamep)
 368                 *osnamep = "VMS";
 369             break;
 370
 371         case FHT_AIX32:
 372             fsidp->Fsid_dev.Minor = EXTRACT_BE_U_2(fhp + 2);
 373             fsidp->Fsid_dev.Major = EXTRACT_BE_U_2(fhp);
 374             fsidp->fsid_code = EXTRACT_BE_U_4(fhp + 4);
 375
 376             *inop = EXTRACT_BE_U_4(fhp + 12);
 377
 378             if (osnamep)
 379                 *osnamep = "AIX32";
 380             break;
 381
 382         case FHT_HPUX9:
 383             fsidp->Fsid_dev.Major = EXTRACT_U_1(fhp);
 384             temp = EXTRACT_BE_U_3(fhp + 1);
 385             fsidp->Fsid_dev.Minor = temp;
 386             fsidp->fsid_code = EXTRACT_BE_U_4(fhp + 4);
 387
 388             *inop = EXTRACT_BE_U_4(fhp + 12);
 389
 390             if (osnamep)
 391                 *osnamep = "HPUX9";
 392             break;
 393
 394         case FHT_UNKNOWN:
 395 #ifdef DEBUG
 396             /* XXX debugging */
 397             for (i = 0; i < len*4; i++)
 398                 (void)fprintf(stderr, "%x.", EXTRACT_U_1(fhp + i));
 399             (void)fprintf(stderr, "\n");
 400 #endif
 401             /* Save the actual handle, so it can be display with -u */
 402             for (i = 0; i < len*4 && i*2 < sizeof(fsidp->Opaque_Handle) - 1; i++)
 403                 (void)nd_snprintf(&(fsidp->Opaque_Handle[i*2]), 3, "%.2X",
 404                                EXTRACT_U_1(fhp + i));
 405             fsidp->Opaque_Handle[i*2] = '\0';
 406
 407             /* XXX for now, give "bogus" values to aid debugging */
 408             fsidp->fsid_code = 0;
 409             fsidp->Fsid_dev.Minor = 257;
 410             fsidp->Fsid_dev.Major = 257;
 411             *inop = 1;
 412
 413             /* display will show this string instead of (257,257) */
 414             if (fsnamep)
 415                 *fsnamep = "Unknown";
 416
 417             if (osnamep)
 418                 *osnamep = "Unknown";
 419             break;
 420
 421         }
 422 }
 423
 424 /*
 425  * Is this a VMS UCX file handle?
 426  *      Check for:
 427  *      (1) leading code byte   [XXX not yet]
 428  *      (2) followed by string of printing chars & spaces
 429  *      (3) followed by string of nulls
 430  */
 431 static int
 432 is_UCX(const unsigned char *fhp, u_int len)
 433 {
 434         u_int i;
 435         int seen_null = 0;
 436
 437         /*
 438          * Require at least 28 bytes of file handle; it's variable-length
 439          * in NFSv3.  "len" is in units of 32-bit words, not bytes.
 440          */
 441         if (len < 28/4)
 442                 return(0);
 443
 444         for (i = 1; i < 14; i++) {
 445             if (ND_ISPRINT(EXTRACT_U_1(fhp + i))) {
 446                 if (seen_null)
 447                    return(0);
 448                 else
 449                    continue;
 450             }
 451             else if (EXTRACT_U_1(fhp + i) == 0) {
 452                 seen_null = 1;
 453                 continue;
 454             }
 455             else
 456                 return(0);
 457         }
 458
 459         return(1);
 460 }