wiretap/vms.c

   1 /* vms.c
   2  *
   3  * Wiretap Library
   4  * Copyright (c) 2001 by Marc Milgram <ethereal@mmilgram.NOSPAMmail.net>
   5  *
   6  * SPDX-License-Identifier: GPL-2.0-or-later
   7  */
   8
   9 /* Notes:
  10  *   TCPIPtrace TCP fragments don't have the header line.  So, we are never
  11  *   to look for that line for the first line of a packet except the first
  12  *   packet.  This allows us to read fragmented packets.  Define
  13  *   TCPIPTRACE_FRAGMENTS_HAVE_HEADER_LINE to expect the first line to be
  14  *   at the start of every packet.
  15  */
  16 #include "config.h"
  17 #include "vms.h"
  18 #include "wtap-int.h"
  19 #include "file_wrappers.h"
  20
  21 #include <wsutil/strtoi.h>
  22
  23 #include <stdlib.h>
  24 #include <string.h>
  25
  26 /* This module reads the output of the various VMS TCPIP trace utilities
  27  * such as TCPIPTRACE, TCPTRACE and UCX$TRACE
  28  *
  29  * It was initially based on toshiba.c and refined with code from cosine.c
  30
  31 --------------------------------------------------------------------------------
  32    Example TCPIPTRACE TCPTRACE output data:
  33
  34    TCPIPtrace full display RCV packet 8 at 10-JUL-2001 14:54:19.56
  35
  36    IP Version = 4,  IHL = 5,  TOS = 00,   Total Length = 84 = ^x0054
  37    IP Identifier  = ^x178F,  Flags (0=0,DF=0,MF=0),
  38          Fragment Offset = 0 = ^x0000,   Calculated Offset = 0 = ^x0000
  39    IP TTL = 64 = ^x40,  Protocol = 17 = ^x11,  Header Checksum = ^x4C71
  40    IP Source Address      = 10.12.1.80
  41    IP Destination Address = 10.12.1.50
  42
  43    UDP Source Port = 731,   UDP Destination Port = 111
  44    UDP Header and Datagram Length = 64 = ^x0040,   Checksum = ^xB6C0
  45
  46    50010C0A   714C1140   00008F17   54000045    0000    E..T....@.Lq...P
  47    27E54C3C | C0B64000   6F00DB02 | 32010C0A    0010    ...2...o.@..<L.'
  48    02000000   A0860100   02000000   00000000    0020    ................
  49    00000000   00000000   00000000   03000000    0030    ................
  50    06000000   01000000   A5860100   00000000    0040    ................
  51                                     00000000    0050    ....
  52 --------------------------------------------------------------------------------
  53
  54    Example UCX$TRACE output data:
  55
  56     UCX INTERnet trace RCV packet seq # = 1 at 14-MAY-2003 11:32:10.93
  57
  58    IP Version = 4,  IHL = 5,  TOS = 00,   Total Length = 583 = ^x0247
  59    IP Identifier  = ^x702E,  Flags (0=0,DF=0,MF=0),
  60          Fragment Offset = 0 = ^x0000,   Calculated Offset = 0 = ^x0000
  61    IP TTL = 128 = ^x80,  Protocol = 17 = ^x11,  Header Checksum = ^x70EC
  62    IP Source Address      = 10.20.4.159
  63    IP Destination Address = 10.20.4.255
  64
  65    UDP Source Port = 138,   UDP Destination Port = 138
  66    UDP Header and Datagram Length = 563 = ^x0233,   Checksum = ^xB913
  67
  68    9F04140A   70EC1180   0000702E   47020045    0000    E..G.p.....p....
  69    B1B80E11 | B9133302   8A008A00 | FF04140A    0010    .........3......
  70    46484648   45200000   1D028A00   9F04140A    0020    ...........EHFHF
  71    43414341   4341434D   454D4546   45454550    0030    PEEEFEMEMCACACAC
  72
  73 --------------------------------------------------------------------------------
  74
  75    Alternate UCX$TRACE type output data:
  76
  77    TCPIP INTERnet trace RCV packet seq # = 1 at 23-OCT-1998 15:19:33.29
  78
  79    IP Version = 4,  IHL = 5,  TOS = 00,   Total Length = 217 = ^x00D9
  80    IP Identifier  = ^x0065,  Flags (0=0,DF=0,MF=0),
  81          Fragment Offset = 0 = ^x0000,   Calculated Offset = 0 = ^x0000
  82    IP TTL = 32 = ^x20,  Protocol = 17 = ^x11,  Header Checksum = ^x8F6C
  83    IP Source Address      = 16.20.168.93
  84    IP Destination Address = 16.20.255.255
  85
  86    UDP Source Port = 138,   UDP Destination Port = 138
  87    UDP Header and Datagram Length = 197 = ^x00C5,   Checksum = ^x0E77
  88
  89    5DA81410   8F6C1120   00000065   D9000045    0000    E...awe.....l....]
  90             | 0E77C500   8A008A00 | FFFF1410    0010    ..........w.
  91
  92 --------------------------------------------------------------------------------
  93
  94 The only difference between the utilities is the Packet header line, primarily
  95 the utility identifier and the packet sequence formats.
  96
  97 There appear to be 2 formats for packet sequencing
  98
  99 Format 1:
 100
 101  ... packet nn at DD-MMM-YYYY hh:mm:ss.ss
 102
 103 Format 2:
 104
 105  ... packet seq # = nn at DD-MMM-YYYY hh:mm:ss.ss
 106
 107 If there are other formats then code will have to be written in parse_vms_packet()
 108 to handle them.
 109
 110 --------------------------------------------------------------------------------
 111
 112  */
 113
 114 /* Magic text to check for VMS-ness of file using possible utility names
 115  *
 116  */
 117 #define VMS_HDR_MAGIC_STR1      "TCPIPtrace"
 118 #define VMS_HDR_MAGIC_STR2      "TCPtrace"
 119 #define VMS_HDR_MAGIC_STR3      "INTERnet trace"
 120
 121 /* Magic text for start of packet */
 122 #define VMS_REC_MAGIC_STR1      VMS_HDR_MAGIC_STR1
 123 #define VMS_REC_MAGIC_STR2      VMS_HDR_MAGIC_STR2
 124 #define VMS_REC_MAGIC_STR3      VMS_HDR_MAGIC_STR3
 125
 126 #define VMS_HEADER_LINES_TO_CHECK    200
 127 #define VMS_LINE_LENGTH              240
 128
 129 static bool vms_read(wtap *wth, wtap_rec *rec, Buffer *buf,
 130     int *err, char **err_info, int64_t *data_offset);
 131 static bool vms_seek_read(wtap *wth, int64_t seek_off,
 132     wtap_rec *rec, Buffer *buf, int *err, char **err_info);
 133 static bool parse_single_hex_dump_line(char* rec, uint8_t *buf,
 134     long byte_offset, int in_off, int remaining_bytes);
 135 static bool parse_vms_packet(FILE_T fh, wtap_rec *rec,
 136     Buffer *buf, int *err, char **err_info);
 137
 138 static int vms_file_type_subtype = -1;
 139
 140 void register_vms(void);
 141
 142 #ifdef TCPIPTRACE_FRAGMENTS_HAVE_HEADER_LINE
 143 /* Seeks to the beginning of the next packet, and returns the
 144    byte offset.  Returns -1 on failure, and sets "*err" to the error
 145    and sets "*err_info" to null or an additional error string. */
 146 static long vms_seek_next_packet(wtap *wth, int *err, char **err_info)
 147 {
 148     long cur_off;
 149     char buf[VMS_LINE_LENGTH];
 150
 151     while (1) {
 152         cur_off = file_tell(wth->fh);
 153         if (cur_off == -1) {
 154             /* Error */
 155             *err = file_error(wth->fh, err_info);
 156             return -1;
 157         }
 158         if (file_gets(buf, sizeof(buf), wth->fh) == NULL) {
 159             /* EOF or error. */
 160             *err = file_error(wth->fh, err_info);
 161             break;
 162         }
 163         if (strstr(buf, VMS_REC_MAGIC_STR1) ||
 164             strstr(buf, VMS_REC_MAGIC_STR2) ||
 165             strstr(buf, VMS_REC_MAGIC_STR2)) {
 166             (void) g_strlcpy(hdr, buf,VMS_LINE_LENGTH);
 167             return cur_off;
 168         }
 169     }
 170     return -1;
 171 }
 172 #endif /* TCPIPTRACE_FRAGMENTS_HAVE_HEADER_LINE */
 173
 174 /* Look through the first part of a file to see if this is
 175  * a VMS trace file.
 176  *
 177  * Returns true if it is, false if it isn't or if we get an I/O error;
 178  * if we get an I/O error, "*err" will be set to a non-zero value and
 179  * "*err_info will be set to null or an additional error string.
 180  *
 181  * Leaves file handle at beginning of line that contains the VMS Magic
 182  * identifier.
 183  */
 184 static bool vms_check_file_type(wtap *wth, int *err, char **err_info)
 185 {
 186     char buf[VMS_LINE_LENGTH];
 187     unsigned reclen, line;
 188     int64_t mpos;
 189
 190     buf[VMS_LINE_LENGTH-1] = '\0';
 191
 192     for (line = 0; line < VMS_HEADER_LINES_TO_CHECK; line++) {
 193         mpos = file_tell(wth->fh);
 194         if (mpos == -1) {
 195             /* Error. */
 196             *err = file_error(wth->fh, err_info);
 197             return false;
 198         }
 199         if (file_gets(buf, VMS_LINE_LENGTH, wth->fh) == NULL) {
 200             /* EOF or error. */
 201             *err = file_error(wth->fh, err_info);
 202             return false;
 203         }
 204
 205         reclen = (unsigned) strlen(buf);
 206         if (reclen < strlen(VMS_HDR_MAGIC_STR1) ||
 207             reclen < strlen(VMS_HDR_MAGIC_STR2) ||
 208             reclen < strlen(VMS_HDR_MAGIC_STR3)) {
 209             continue;
 210         }
 211
 212         if (strstr(buf, VMS_HDR_MAGIC_STR1) ||
 213             strstr(buf, VMS_HDR_MAGIC_STR2) ||
 214             strstr(buf, VMS_HDR_MAGIC_STR3)) {
 215             /* Go back to the beginning of this line, so we will
 216              * re-read it. */
 217             if (file_seek(wth->fh, mpos, SEEK_SET, err) == -1) {
 218                 /* Error. */
 219                 return false;
 220             }
 221             return true;
 222         }
 223     }
 224     *err = 0;
 225     return false;
 226 }
 227
 228
 229 wtap_open_return_val vms_open(wtap *wth, int *err, char **err_info)
 230 {
 231     /* Look for VMS header */
 232     if (!vms_check_file_type(wth, err, err_info)) {
 233         if (*err != 0 && *err != WTAP_ERR_SHORT_READ)
 234             return WTAP_OPEN_ERROR;
 235         return WTAP_OPEN_NOT_MINE;
 236     }
 237
 238     wth->file_encap = WTAP_ENCAP_RAW_IP;
 239     wth->file_type_subtype = vms_file_type_subtype;
 240     wth->snapshot_length = 0; /* not known */
 241     wth->subtype_read = vms_read;
 242     wth->subtype_seek_read = vms_seek_read;
 243     wth->file_tsprec = WTAP_TSPREC_10_MSEC;
 244
 245     /*
 246      * Add an IDB; we don't know how many interfaces were
 247      * involved, so we just say one interface, about which
 248      * we only know the link-layer type, snapshot length,
 249      * and time stamp resolution.
 250      */
 251     wtap_add_generated_idb(wth);
 252
 253     return WTAP_OPEN_MINE;
 254 }
 255
 256 /* Find the next packet and parse it; called from wtap_read(). */
 257 static bool vms_read(wtap *wth, wtap_rec *rec, Buffer *buf,
 258     int *err, char **err_info, int64_t *data_offset)
 259 {
 260     int64_t  offset = 0;
 261
 262     /* Find the next packet */
 263 #ifdef TCPIPTRACE_FRAGMENTS_HAVE_HEADER_LINE
 264     offset = vms_seek_next_packet(wth, err, err_info);
 265 #else
 266     offset = file_tell(wth->fh);
 267 #endif
 268     if (offset < 1) {
 269         *err = file_error(wth->fh, err_info);
 270         return false;
 271     }
 272     *data_offset = offset;
 273
 274     /* Parse the packet */
 275     return parse_vms_packet(wth->fh, rec, buf, err, err_info);
 276 }
 277
 278 /* Used to read packets in random-access fashion */
 279 static bool
 280 vms_seek_read(wtap *wth, int64_t seek_off, wtap_rec *rec,
 281     Buffer *buf, int *err, char **err_info)
 282 {
 283     if (file_seek(wth->random_fh, seek_off - 1, SEEK_SET, err) == -1)
 284         return false;
 285
 286     if (!parse_vms_packet(wth->random_fh, rec, buf, err, err_info)) {
 287         if (*err == 0)
 288             *err = WTAP_ERR_SHORT_READ;
 289         return false;
 290     }
 291     return true;
 292 }
 293
 294 /* isdumpline assumes that dump lines start with some non-alphanumerics
 295  * followed by 4 hex numbers - each 8 digits long, each hex number followed
 296  * by 3 spaces.
 297  */
 298 static int
 299 isdumpline( char *line )
 300 {
 301     int i, j;
 302
 303     while (*line && !g_ascii_isalnum(*line))
 304         line++;
 305
 306     for (j=0; j<4; j++) {
 307         for (i=0; i<8; i++, line++)
 308             if (! g_ascii_isxdigit(*line))
 309                 return false;
 310
 311         for (i=0; i<3; i++, line++)
 312             if (*line != ' ')
 313                 return false;
 314     }
 315
 316     return g_ascii_isspace(*line);
 317 }
 318
 319 /* Parses a packet record. */
 320 static bool
 321 parse_vms_packet(FILE_T fh, wtap_rec *rec, Buffer *buf, int *err, char **err_info)
 322 {
 323     char    line[VMS_LINE_LENGTH + 1];
 324     int     num_items_scanned;
 325     bool have_pkt_len = false;
 326     uint32_t pkt_len = 0;
 327     int     pktnum;
 328     int     csec = 101;
 329     struct tm tm;
 330     char mon[4] = {'J', 'A', 'N', 0};
 331     char   *p;
 332     const char *endp;
 333     static const char months[] = "JANFEBMARAPRMAYJUNJULAUGSEPOCTNOVDEC";
 334     uint32_t i;
 335     int     offset = 0;
 336     uint8_t *pd;
 337
 338     tm.tm_year = 1970;
 339     tm.tm_mon = 0;
 340     tm.tm_mday = 1;
 341     tm.tm_hour = 1;
 342     tm.tm_min = 1;
 343     tm.tm_sec = 1;
 344
 345     /* Skip lines until one starts with a hex number */
 346     do {
 347         if (file_gets(line, VMS_LINE_LENGTH, fh) == NULL) {
 348             *err = file_error(fh, err_info);
 349             if ((*err == 0) && (csec != 101)) {
 350                 *err = WTAP_ERR_SHORT_READ;
 351             }
 352             return false;
 353         }
 354         line[VMS_LINE_LENGTH] = '\0';
 355
 356         if ((csec == 101) && (p = strstr(line, "packet ")) != NULL
 357             && (! strstr(line, "could not save "))) {
 358             /* Find text in line starting with "packet ". */
 359
 360             /* First look for the Format 1 type sequencing */
 361             num_items_scanned = sscanf(p,
 362                                        "packet %9d at %2d-%3s-%4d %2d:%2d:%2d.%9d",
 363                                        &pktnum, &tm.tm_mday, mon,
 364                                        &tm.tm_year, &tm.tm_hour,
 365                                        &tm.tm_min, &tm.tm_sec, &csec);
 366             /* Next look for the Format 2 type sequencing */
 367             if (num_items_scanned != 8) {
 368               num_items_scanned = sscanf(p,
 369                                          "packet seq # = %9d at %2d-%3s-%4d %2d:%2d:%2d.%9d",
 370                                          &pktnum, &tm.tm_mday, mon,
 371                                          &tm.tm_year, &tm.tm_hour,
 372                                          &tm.tm_min, &tm.tm_sec, &csec);
 373             }
 374             /* if unknown format then exit with error        */
 375             /* We will need to add code to handle new format */
 376             if (num_items_scanned != 8) {
 377                 *err = WTAP_ERR_BAD_FILE;
 378                 *err_info = g_strdup("vms: header line not valid");
 379                 return false;
 380             }
 381         }
 382         if ( (! have_pkt_len) && (p = strstr(line, "Length "))) {
 383             p += sizeof("Length ");
 384             while (*p && ! g_ascii_isdigit(*p))
 385                 p++;
 386
 387             if ( !*p ) {
 388                 *err = WTAP_ERR_BAD_FILE;
 389                 *err_info = g_strdup("vms: Length field not valid");
 390                 return false;
 391             }
 392
 393             if (!ws_strtou32(p, &endp, &pkt_len) || (*endp != '\0' && !g_ascii_isspace(*endp))) {
 394                 *err = WTAP_ERR_BAD_FILE;
 395                 *err_info = ws_strdup_printf("vms: Length field '%s' not valid", p);
 396                 return false;
 397             }
 398             have_pkt_len = true;
 399             break;
 400         }
 401     } while (! isdumpline(line));
 402     if (! have_pkt_len) {
 403         *err = WTAP_ERR_BAD_FILE;
 404         *err_info = ws_strdup_printf("vms: Length field not found");
 405         return false;
 406     }
 407     if (pkt_len > WTAP_MAX_PACKET_SIZE_STANDARD) {
 408         /*
 409          * Probably a corrupt capture file; return an error,
 410          * so that our caller doesn't blow up trying to allocate
 411          * space for an immensely-large packet.
 412          */
 413         *err = WTAP_ERR_BAD_FILE;
 414         *err_info = ws_strdup_printf("vms: File has %u-byte packet, bigger than maximum of %u",
 415                                     pkt_len, WTAP_MAX_PACKET_SIZE_STANDARD);
 416         return false;
 417     }
 418
 419     p = strstr(months, mon);
 420     if (p)
 421         tm.tm_mon = (int) (p - months) / 3;
 422     tm.tm_year -= 1900;
 423     tm.tm_isdst = -1;
 424
 425     rec->rec_type = REC_TYPE_PACKET;
 426     rec->block = wtap_block_create(WTAP_BLOCK_PACKET);
 427     rec->presence_flags = WTAP_HAS_TS;
 428     rec->ts.secs = mktime(&tm);
 429     rec->ts.nsecs = csec * 10000000;
 430     rec->rec_header.packet_header.caplen = pkt_len;
 431     rec->rec_header.packet_header.len = pkt_len;
 432
 433     /* Make sure we have enough room for the packet */
 434     ws_buffer_assure_space(buf, pkt_len);
 435     pd = ws_buffer_start_ptr(buf);
 436
 437     /* Convert the ASCII hex dump to binary data */
 438     for (i = 0; i < pkt_len; i += 16) {
 439         if (file_gets(line, VMS_LINE_LENGTH, fh) == NULL) {
 440             *err = file_error(fh, err_info);
 441             if (*err == 0) {
 442                 *err = WTAP_ERR_SHORT_READ;
 443             }
 444             return false;
 445         }
 446         line[VMS_LINE_LENGTH] = '\0';
 447         if (i == 0) {
 448             while (! isdumpline(line)) { /* advance to start of hex data */
 449                 if (file_gets(line, VMS_LINE_LENGTH, fh) == NULL) {
 450                     *err = file_error(fh, err_info);
 451                     if (*err == 0) {
 452                         *err = WTAP_ERR_SHORT_READ;
 453                     }
 454                     return false;
 455                 }
 456                 line[VMS_LINE_LENGTH] = '\0';
 457             }
 458             while (line[offset] && !g_ascii_isxdigit(line[offset]))
 459                 offset++;
 460         }
 461         if (!parse_single_hex_dump_line(line, pd, i,
 462                                         offset, pkt_len - i)) {
 463             *err = WTAP_ERR_BAD_FILE;
 464             *err_info = g_strdup("vms: hex dump not valid");
 465             return false;
 466         }
 467     }
 468     /* Avoid TCPIPTRACE-W-BUFFERSFUL, TCPIPtrace could not save n packets.
 469      * errors.
 470      *
 471      * XXX - when we support packet drop report information in the
 472      * Wiretap API, we should parse those lines and return "n" as
 473      * a packet drop count. */
 474     if (!file_gets(line, VMS_LINE_LENGTH, fh)) {
 475         *err = file_error(fh, err_info);
 476         if (*err == 0) {
 477             /* There is no next line, so there's no "TCPIPtrace could not
 478              * save n packets" line; not an error. */
 479             return true;
 480         }
 481         return false;
 482     }
 483     return true;
 484 }
 485
 486 /*
 487           1         2         3         4
 488 0123456789012345678901234567890123456789012345
 489    50010C0A   A34C0640   00009017   2C000045    0000    E..,....@.L....P
 490    00000000   14945E52   0A00DC02 | 32010C0A    0010    ...2....R^......
 491        0000 | B4050402   00003496   00020260    0020    `....4........
 492 */
 493
 494 #define START_POS    7
 495 #define HEX_LENGTH    ((8 * 4) + 7) /* eight clumps of 4 bytes with 7 inner spaces */
 496 /* Take a string representing one line from a hex dump and converts the
 497  * text to binary data. We check the printed offset with the offset
 498  * we are passed to validate the record. We place the bytes in the buffer
 499  * at the specified offset.
 500  *
 501  * Returns true if good hex dump, false if bad.
 502  */
 503 static bool
 504 parse_single_hex_dump_line(char* rec, uint8_t *buf, long byte_offset,
 505                int in_off, int remaining_bytes) {
 506
 507     int        i;
 508     char        *s;
 509     int        value;
 510     static const int offsets[16] = {39,37,35,33,28,26,24,22,17,15,13,11,6,4,2,0};
 511     char lbuf[3] = {0,0,0};
 512
 513
 514     /* Get the byte_offset directly from the record */
 515     s = rec;
 516     value = (int)strtoul(s + 45 + in_off, NULL, 16);    /* XXX - error check? */
 517
 518     if (value != byte_offset) {
 519         return false;
 520     }
 521
 522     if (remaining_bytes > 16)
 523         remaining_bytes = 16;
 524
 525     /* Read the octets right to left, as that is how they are displayed
 526      * in VMS.
 527      */
 528
 529     for (i = 0; i < remaining_bytes; i++) {
 530         lbuf[0] = rec[offsets[i] + in_off];
 531         lbuf[1] = rec[offsets[i] + 1 + in_off];
 532
 533         buf[byte_offset + i] = (uint8_t) strtoul(lbuf, NULL, 16);
 534     }
 535
 536     return true;
 537 }
 538
 539 static const struct supported_block_type vms_blocks_supported[] = {
 540     /*
 541      * We support packet blocks, with no comments or other options.
 542      */
 543     { WTAP_BLOCK_PACKET, MULTIPLE_BLOCKS_SUPPORTED, NO_OPTIONS_SUPPORTED }
 544 };
 545
 546 static const struct file_type_subtype_info vms_info = {
 547     "TCPIPtrace (VMS)", "tcpiptrace", "txt", NULL,
 548     false, BLOCKS_SUPPORTED(vms_blocks_supported),
 549     NULL, NULL, NULL
 550 };
 551
 552 void register_vms(void)
 553 {
 554     vms_file_type_subtype = wtap_register_file_type_subtype(&vms_info);
 555
 556     /*
 557      * Register name for backwards compatibility with the
 558      * wtap_filetypes table in Lua.
 559      */
 560     wtap_register_backwards_compatibility_lua_name("VMS",
 561                                                    vms_file_type_subtype);
 562 }
 563
 564 /*
 565  * Editor modelines  -  https://www.wireshark.org/tools/modelines.html
 566  *
 567  * Local variables:
 568  * c-basic-offset: 4
 569  * tab-width: 8
 570  * indent-tabs-mode: nil
 571  * End:
 572  *
 573  * vi: set shiftwidth=4 tabstop=8 expandtab:
 574  * :indentSize=4:tabSize=8:noTabs=true:
 575  */