ui/text_import.c

   1 /* text_import.c
   2  * State machine for text import
   3  * November 2010, Jaap Keuter <jaap.keuter@xs4all.nl>
   4  *
   5  * $Id$
   6  *
   7  * Wireshark - Network traffic analyzer
   8  * By Gerald Combs <gerald@wireshark.org>
   9  * Copyright 1998 Gerald Combs
  10  *
  11  * Based on text2pcap.c by Ashok Narayanan <ashokn@cisco.com>
  12  *
  13  * This program is free software; you can redistribute it and/or
  14  * modify it under the terms of the GNU General Public License
  15  * as published by the Free Software Foundation; either version 2
  16  * of the License, or (at your option) any later version.
  17  *
  18  * This program is distributed in the hope that it will be useful,
  19  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  21  * GNU General Public License for more details.
  22  *
  23  * You should have received a copy of the GNU General Public License
  24  * along with this program; if not, write to the Free Software
  25  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
  26  * USA.
  27  */
  28
  29 /*******************************************************************************
  30  *
  31  * This utility reads in an ASCII hexdump of this common format:
  32  *
  33  * 00000000  00 E0 1E A7 05 6F 00 10 5A A0 B9 12 08 00 46 00 .....o..Z.....F.
  34  * 00000010  03 68 00 00 00 00 0A 2E EE 33 0F 19 08 7F 0F 19 .h.......3......
  35  * 00000020  03 80 94 04 00 00 10 01 16 A2 0A 00 03 50 00 0C .............P..
  36  * 00000030  01 01 0F 19 03 80 11 01 1E 61 00 0C 03 01 0F 19 .........a......
  37  *
  38  * Each bytestring line consists of an offset, one or more bytes, and
  39  * text at the end. An offset is defined as a hex string of more than
  40  * two characters. A byte is defined as a hex string of exactly two
  41  * characters. The text at the end is ignored, as is any text before
  42  * the offset. Bytes read from a bytestring line are added to the
  43  * current packet only if all the following conditions are satisfied:
  44  *
  45  * - No text appears between the offset and the bytes (any bytes appearing after
  46  *   such text would be ignored)
  47  *
  48  * - The offset must be arithmetically correct, i.e. if the offset is 00000020, then
  49  *   exactly 32 bytes must have been read into this packet before this. If the offset
  50  *   is wrong, the packet is immediately terminated
  51  *
  52  * A packet start is signalled by a zero offset.
  53  *
  54  * Lines starting with #TEXT2PCAP are directives. These allow the user
  55  * to embed instructions into the capture file which allows text2pcap
  56  * to take some actions (e.g. specifying the encapsulation
  57  * etc.). Currently no directives are implemented.
  58  *
  59  * Lines beginning with # which are not directives are ignored as
  60  * comments. Currently all non-hexdump text is ignored by text2pcap;
  61  * in the future, text processing may be added, but lines prefixed
  62  * with '#' will still be ignored.
  63  *
  64  * The output is a libpcap packet containing Ethernet frames by
  65  * default. This program takes options which allow the user to add
  66  * dummy Ethernet, IP and UDP or TCP headers to the packets in order
  67  * to allow dumps of L3 or higher protocols to be decoded.
  68  *
  69  * Considerable flexibility is built into this code to read hexdumps
  70  * of slightly different formats. For example, any text prefixing the
  71  * hexdump line is dropped (including mail forwarding '>'). The offset
  72  * can be any hex number of four digits or greater.
  73  *
  74  * This converter cannot read a single packet greater than 64KiB-1. Packet
  75  * snaplength is automatically set to 64KiB-1.
  76  */
  77
  78 #include "config.h"
  79
  80 /*
  81  * Just make sure we include the prototype for strptime as well
  82  * (needed for glibc 2.2) but make sure we do this only if not
  83  * yet defined.
  84  */
  85 #ifndef __USE_XOPEN
  86 #  define __USE_XOPEN
  87 #endif
  88 #ifndef _XOPEN_SOURCE
  89 #  ifndef __sun
  90 #    define _XOPEN_SOURCE 600
  91 #  endif
  92 #endif
  93
  94 /*
  95  * Defining _XOPEN_SOURCE is needed on some platforms, e.g. platforms
  96  * using glibc, to expand the set of things system header files define.
  97  *
  98  * Unfortunately, on other platforms, such as some versions of Solaris
  99  * (including Solaris 10), it *reduces* that set as well, causing
 100  * strptime() not to be declared, presumably because the version of the
 101  * X/Open spec that _XOPEN_SOURCE implies doesn't include strptime() and
 102  * blah blah blah namespace pollution blah blah blah.
 103  *
 104  * So we define __EXTENSIONS__ so that "strptime()" is declared.
 105  */
 106 #ifndef __EXTENSIONS__
 107 #  define __EXTENSIONS__
 108 #endif
 109
 110 #include <ctype.h>
 111 #include <stdio.h>
 112 #include <stdlib.h>
 113 #include <string.h>
 114 #include <wsutil/file_util.h>
 115
 116 #include <time.h>
 117 #include <glib.h>
 118
 119 #ifdef HAVE_UNISTD_H
 120 # include <unistd.h>
 121 #endif
 122
 123 #include <errno.h>
 124 #include <assert.h>
 125
 126 #include <epan/tvbuff.h>
 127 #include <wsutil/crc32.h>
 128 #include <epan/in_cksum.h>
 129
 130 #ifdef NEED_STRPTIME_H
 131 # include "wsutil/strptime.h"
 132 #endif
 133
 134 #include "text_import.h"
 135 #include "text_import_scanner.h"
 136
 137 /*--- Options --------------------------------------------------------------------*/
 138
 139 /* Debug level */
 140 static int debug = 0;
 141
 142 /* Dummy Ethernet header */
 143 static int hdr_ethernet = FALSE;
 144 static guint32 hdr_ethernet_proto = 0;
 145
 146 /* Dummy IP header */
 147 static int hdr_ip = FALSE;
 148 static long hdr_ip_proto = 0;
 149
 150 /* Dummy UDP header */
 151 static int hdr_udp = FALSE;
 152 static guint32 hdr_dest_port = 0;
 153 static guint32 hdr_src_port = 0;
 154
 155 /* Dummy TCP header */
 156 static int hdr_tcp = FALSE;
 157
 158 /* Dummy SCTP header */
 159 static int hdr_sctp = FALSE;
 160 static guint32 hdr_sctp_src  = 0;
 161 static guint32 hdr_sctp_dest = 0;
 162 static guint32 hdr_sctp_tag  = 0;
 163
 164 /* Dummy DATA chunk header */
 165 static int hdr_data_chunk = FALSE;
 166 static guint8  hdr_data_chunk_type = 0;
 167 static guint8  hdr_data_chunk_bits = 3;
 168 static guint32 hdr_data_chunk_tsn  = 0;
 169 static guint16 hdr_data_chunk_sid  = 0;
 170 static guint16 hdr_data_chunk_ssn  = 0;
 171 static guint32 hdr_data_chunk_ppid = 0;
 172
 173 static gboolean has_direction = FALSE;
 174 static guint32 direction = 0;
 175
 176 /*--- Local data -----------------------------------------------------------------*/
 177
 178 /* This is where we store the packet currently being built */
 179 static guint8 *packet_buf;
 180 static guint32 curr_offset = 0;
 181 static guint32 max_offset = IMPORT_MAX_PACKET;
 182 static guint32 packet_start = 0;
 183 static void start_new_packet (void);
 184
 185 /* This buffer contains strings present before the packet offset 0 */
 186 #define PACKET_PREAMBLE_MAX_LEN    2048
 187 static guint8 packet_preamble[PACKET_PREAMBLE_MAX_LEN+1];
 188 static int packet_preamble_len = 0;
 189
 190 /* Time code of packet, derived from packet_preamble */
 191 static time_t ts_sec = 0;
 192 static guint32 ts_usec = 0;
 193 static char *ts_fmt = NULL;
 194 static struct tm timecode_default;
 195
 196 static wtap_dumper* wdh;
 197
 198 /* HDR_ETH Offset base to parse */
 199 static guint32 offset_base = 16;
 200
 201 /* ----- State machine -----------------------------------------------------------*/
 202
 203 /* Current state of parser */
 204 typedef enum {
 205     INIT,             /* Waiting for start of new packet */
 206     START_OF_LINE,    /* Starting from beginning of line */
 207     READ_OFFSET,      /* Just read the offset */
 208     READ_BYTE,        /* Just read a byte */
 209     READ_TEXT         /* Just read text - ignore until EOL */
 210 } parser_state_t;
 211 static parser_state_t state = INIT;
 212
 213 static const char *state_str[] = {"Init",
 214                            "Start-of-line",
 215                            "Offset",
 216                            "Byte",
 217                            "Text"
 218 };
 219
 220 static const char *token_str[] = {"",
 221                            "Byte",
 222                            "Offset",
 223                            "Directive",
 224                            "Text",
 225                            "End-of-line"
 226 };
 227
 228 /* ----- Skeleton Packet Headers --------------------------------------------------*/
 229
 230 typedef struct {
 231     guint8  dest_addr[6];
 232     guint8  src_addr[6];
 233     guint16 l3pid;
 234 } hdr_ethernet_t;
 235
 236 static hdr_ethernet_t HDR_ETHERNET = {
 237     {0x20, 0x52, 0x45, 0x43, 0x56, 0x00},
 238     {0x20, 0x53, 0x45, 0x4E, 0x44, 0x00},
 239     0};
 240
 241 typedef struct {
 242     guint8  ver_hdrlen;
 243     guint8  dscp;
 244     guint16 packet_length;
 245     guint16 identification;
 246     guint8  flags;
 247     guint8  fragment;
 248     guint8  ttl;
 249     guint8  protocol;
 250     guint16 hdr_checksum;
 251     guint32 src_addr;
 252     guint32 dest_addr;
 253 } hdr_ip_t;
 254
 255 static hdr_ip_t HDR_IP =
 256   {0x45, 0, 0, 0x3412, 0, 0, 0xff, 0, 0, 0x01010101, 0x02020202};
 257
 258 static struct {         /* pseudo header for checksum calculation */
 259     guint32 src_addr;
 260     guint32 dest_addr;
 261     guint8  zero;
 262     guint8  protocol;
 263     guint16 length;
 264 } pseudoh;
 265
 266 typedef struct {
 267     guint16 source_port;
 268     guint16 dest_port;
 269     guint16 length;
 270     guint16 checksum;
 271 } hdr_udp_t;
 272
 273 static hdr_udp_t HDR_UDP = {0, 0, 0, 0};
 274
 275 typedef struct {
 276     guint16 source_port;
 277     guint16 dest_port;
 278     guint32 seq_num;
 279     guint32 ack_num;
 280     guint8  hdr_length;
 281     guint8  flags;
 282     guint16 window;
 283     guint16 checksum;
 284     guint16 urg;
 285 } hdr_tcp_t;
 286
 287 static hdr_tcp_t HDR_TCP = {0, 0, 0, 0, 0x50, 0, 0, 0, 0};
 288
 289 typedef struct {
 290     guint16 src_port;
 291     guint16 dest_port;
 292     guint32 tag;
 293     guint32 checksum;
 294 } hdr_sctp_t;
 295
 296 static hdr_sctp_t HDR_SCTP = {0, 0, 0, 0};
 297
 298 typedef struct {
 299     guint8  type;
 300     guint8  bits;
 301     guint16 length;
 302     guint32 tsn;
 303     guint16 sid;
 304     guint16 ssn;
 305     guint32 ppid;
 306 } hdr_data_chunk_t;
 307
 308 static hdr_data_chunk_t HDR_DATA_CHUNK = {0, 0, 0, 0, 0, 0, 0};
 309
 310 /* Link-layer type; see net/bpf.h for details */
 311 static guint pcap_link_type = 1;   /* Default is DLT_EN10MB */
 312
 313 /*----------------------------------------------------------------------
 314  * Parse a single hex number
 315  * Will abort the program if it can't parse the number
 316  * Pass in TRUE if this is an offset, FALSE if not
 317  */
 318 static guint32
 319 parse_num (const char *str, int offset)
 320 {
 321     unsigned long num;
 322     char *c;
 323
 324     num = strtoul(str, &c, offset ? offset_base : 16);
 325     if (c==str) {
 326         fprintf(stderr, "FATAL ERROR: Bad hex number? [%s]\n", str);
 327     }
 328     return (guint32)num;
 329 }
 330
 331 /*----------------------------------------------------------------------
 332  * Write this byte into current packet
 333  */
 334 static void
 335 write_byte (const char *str)
 336 {
 337     guint32 num;
 338
 339     num = parse_num(str, FALSE);
 340     packet_buf[curr_offset] = (guint8) num;
 341     curr_offset ++;
 342     if (curr_offset >= max_offset) /* packet full */
 343         start_new_packet();
 344 }
 345
 346 /*----------------------------------------------------------------------
 347  * Remove bytes from the current packet
 348  */
 349 static void
 350 unwrite_bytes (guint32 nbytes)
 351 {
 352     curr_offset -= nbytes;
 353 }
 354
 355 /*----------------------------------------------------------------------
 356  * Determin SCTP chunk padding length
 357  */
 358 static guint32
 359 number_of_padding_bytes (guint32 length)
 360 {
 361   guint32 remainder;
 362
 363   remainder = length % 4;
 364
 365   if (remainder == 0)
 366     return 0;
 367   else
 368     return 4 - remainder;
 369 }
 370
 371 /*----------------------------------------------------------------------
 372  * Write current packet out
 373  */
 374 void
 375 write_current_packet (void)
 376 {
 377     int prefix_length = 0;
 378     int proto_length = 0;
 379     int ip_length = 0;
 380     int eth_trailer_length = 0;
 381     int prefix_index = 0;
 382     int i, padding_length;
 383
 384     if (curr_offset > 0) {
 385         /* Write the packet */
 386
 387         /* Compute packet length */
 388         prefix_length = 0;
 389         if (hdr_data_chunk) { prefix_length += (int)sizeof(HDR_DATA_CHUNK); }
 390         if (hdr_sctp) { prefix_length += (int)sizeof(HDR_SCTP); }
 391         if (hdr_udp) { prefix_length += (int)sizeof(HDR_UDP); proto_length = prefix_length + curr_offset; }
 392         if (hdr_tcp) { prefix_length += (int)sizeof(HDR_TCP); proto_length = prefix_length + curr_offset; }
 393         if (hdr_ip) {
 394             prefix_length += (int)sizeof(HDR_IP);
 395             ip_length = prefix_length + curr_offset + ((hdr_data_chunk) ? number_of_padding_bytes(curr_offset) : 0);
 396         }
 397         if (hdr_ethernet) { prefix_length += (int)sizeof(HDR_ETHERNET); }
 398
 399         /* Make room for dummy header */
 400         memmove(&packet_buf[prefix_length], packet_buf, curr_offset);
 401
 402         if (hdr_ethernet) {
 403             /* Pad trailer */
 404             if (prefix_length + curr_offset < 60) {
 405                 eth_trailer_length = 60 - (prefix_length + curr_offset);
 406             }
 407         }
 408
 409         /* Write Ethernet header */
 410         if (hdr_ethernet) {
 411             HDR_ETHERNET.l3pid = g_htons(hdr_ethernet_proto);
 412             memcpy(&packet_buf[prefix_index], &HDR_ETHERNET, sizeof(HDR_ETHERNET));
 413             prefix_index += (int)sizeof(HDR_ETHERNET);
 414         }
 415
 416         /* Write IP header */
 417         if (hdr_ip) {
 418             vec_t cksum_vector[1];
 419
 420             HDR_IP.packet_length = g_htons(ip_length);
 421             HDR_IP.protocol = (guint8) hdr_ip_proto;
 422             HDR_IP.hdr_checksum = 0;
 423             cksum_vector[0].ptr = (guint8 *)&HDR_IP; cksum_vector[0].len = sizeof(HDR_IP);
 424             HDR_IP.hdr_checksum = in_cksum(cksum_vector, 1);
 425
 426             memcpy(&packet_buf[prefix_index], &HDR_IP, sizeof(HDR_IP));
 427             prefix_index += (int)sizeof(HDR_IP);
 428         }
 429
 430         /* initialize pseudo header for checksum calculation */
 431         pseudoh.src_addr    = HDR_IP.src_addr;
 432         pseudoh.dest_addr   = HDR_IP.dest_addr;
 433         pseudoh.zero        = 0;
 434         pseudoh.protocol    = (guint8) hdr_ip_proto;
 435         pseudoh.length      = g_htons(proto_length);
 436
 437         /* Write UDP header */
 438         if (hdr_udp) {
 439             vec_t cksum_vector[3];
 440
 441             HDR_UDP.source_port = g_htons(hdr_src_port);
 442             HDR_UDP.dest_port = g_htons(hdr_dest_port);
 443             HDR_UDP.length = g_htons(proto_length);
 444
 445             HDR_UDP.checksum = 0;
 446             cksum_vector[0].ptr = (guint8 *)&pseudoh; cksum_vector[0].len = sizeof(pseudoh);
 447             cksum_vector[1].ptr = (guint8 *)&HDR_UDP; cksum_vector[1].len = sizeof(HDR_UDP);
 448             cksum_vector[2].ptr = &packet_buf[prefix_length]; cksum_vector[2].len = curr_offset;
 449             HDR_UDP.checksum = in_cksum(cksum_vector, 3);
 450
 451             memcpy(&packet_buf[prefix_index], &HDR_UDP, sizeof(HDR_UDP));
 452             prefix_index += (int)sizeof(HDR_UDP);
 453         }
 454
 455         /* Write TCP header */
 456         if (hdr_tcp) {
 457             vec_t cksum_vector[3];
 458
 459             HDR_TCP.source_port = g_htons(hdr_src_port);
 460             HDR_TCP.dest_port = g_htons(hdr_dest_port);
 461             /* HDR_TCP.seq_num already correct */
 462             HDR_TCP.window = g_htons(0x2000);
 463
 464             HDR_TCP.checksum = 0;
 465             cksum_vector[0].ptr = (guint8 *)&pseudoh; cksum_vector[0].len = sizeof(pseudoh);
 466             cksum_vector[1].ptr = (guint8 *)&HDR_TCP; cksum_vector[1].len = sizeof(HDR_TCP);
 467             cksum_vector[2].ptr = &packet_buf[prefix_length]; cksum_vector[2].len = curr_offset;
 468             HDR_TCP.checksum = in_cksum(cksum_vector, 3);
 469
 470             memcpy(&packet_buf[prefix_index], &HDR_TCP, sizeof(HDR_TCP));
 471             prefix_index += (int)sizeof(HDR_TCP);
 472         }
 473
 474         /* Compute DATA chunk header and append padding */
 475         if (hdr_data_chunk) {
 476             HDR_DATA_CHUNK.type   = hdr_data_chunk_type;
 477             HDR_DATA_CHUNK.bits   = hdr_data_chunk_bits;
 478             HDR_DATA_CHUNK.length = g_htons(curr_offset + sizeof(HDR_DATA_CHUNK));
 479             HDR_DATA_CHUNK.tsn    = g_htonl(hdr_data_chunk_tsn);
 480             HDR_DATA_CHUNK.sid    = g_htons(hdr_data_chunk_sid);
 481             HDR_DATA_CHUNK.ssn    = g_htons(hdr_data_chunk_ssn);
 482             HDR_DATA_CHUNK.ppid   = g_htonl(hdr_data_chunk_ppid);
 483
 484             padding_length = number_of_padding_bytes(curr_offset);
 485             for (i=0; i<padding_length; i++)
 486                 packet_buf[prefix_length+curr_offset+i] = 0;
 487             curr_offset += padding_length;
 488         }
 489
 490         /* Write SCTP header */
 491         if (hdr_sctp) {
 492             HDR_SCTP.src_port  = g_htons(hdr_sctp_src);
 493             HDR_SCTP.dest_port = g_htons(hdr_sctp_dest);
 494             HDR_SCTP.tag       = g_htonl(hdr_sctp_tag);
 495             HDR_SCTP.checksum  = g_htonl(0);
 496
 497             HDR_SCTP.checksum  = crc32c_calculate(&HDR_SCTP, sizeof(HDR_SCTP), CRC32C_PRELOAD);
 498             if (hdr_data_chunk)
 499                 HDR_SCTP.checksum  = crc32c_calculate(&HDR_DATA_CHUNK, sizeof(HDR_DATA_CHUNK), HDR_SCTP.checksum);
 500             HDR_SCTP.checksum  = g_htonl(~crc32c_calculate(&packet_buf[prefix_length], curr_offset, HDR_SCTP.checksum));
 501
 502             memcpy(&packet_buf[prefix_index], &HDR_SCTP, sizeof(HDR_SCTP));
 503             prefix_index += (int)sizeof(HDR_SCTP);
 504         }
 505
 506         /* Write DATA chunk header */
 507         if (hdr_data_chunk) {
 508             memcpy(&packet_buf[prefix_index], &HDR_DATA_CHUNK, sizeof(HDR_DATA_CHUNK));
 509             /*prefix_index += (int)sizeof(HDR_DATA_CHUNK);*/
 510         }
 511
 512         /* Write Ethernet trailer */
 513         if (hdr_ethernet && eth_trailer_length > 0) {
 514             memset(&packet_buf[prefix_length+curr_offset], 0, eth_trailer_length);
 515         }
 516
 517         HDR_TCP.seq_num = g_ntohl(HDR_TCP.seq_num) + curr_offset;
 518         HDR_TCP.seq_num = g_htonl(HDR_TCP.seq_num);
 519
 520         {
 521             /* Write the packet */
 522             struct wtap_pkthdr pkthdr;
 523             int err;
 524
 525             pkthdr.ts.secs = (guint32)ts_sec;
 526             pkthdr.ts.nsecs = ts_usec * 1000;
 527             if (ts_fmt == NULL) { ts_usec++; }  /* fake packet counter */
 528             pkthdr.caplen = pkthdr.len = prefix_length + curr_offset + eth_trailer_length;
 529             pkthdr.pkt_encap = pcap_link_type;
 530             pkthdr.interface_id = 0;
 531             pkthdr.presence_flags = 0;
 532             pkthdr.opt_comment = NULL;
 533             pkthdr.drop_count = 0;
 534             pkthdr.pack_flags = 0;
 535             pkthdr.pack_flags |= direction;
 536             pkthdr.presence_flags = WTAP_HAS_CAP_LEN|WTAP_HAS_INTERFACE_ID|WTAP_HAS_TS|WTAP_HAS_PACK_FLAGS;
 537
 538             wtap_dump(wdh, &pkthdr, packet_buf, &err);
 539         }
 540     }
 541
 542     packet_start += curr_offset;
 543     curr_offset = 0;
 544 }
 545
 546
 547 /*----------------------------------------------------------------------
 548  * Append a token to the packet preamble.
 549  */
 550 static void
 551 append_to_preamble(char *str)
 552 {
 553     size_t toklen;
 554
 555     if (packet_preamble_len != 0) {
 556         if (packet_preamble_len == PACKET_PREAMBLE_MAX_LEN)
 557             return;    /* no room to add more preamble */
 558         /* Add a blank separator between the previous token and this token. */
 559         packet_preamble[packet_preamble_len++] = ' ';
 560     }
 561     toklen = strlen(str);
 562     if (toklen != 0) {
 563         if (packet_preamble_len + toklen > PACKET_PREAMBLE_MAX_LEN)
 564             return;    /* no room to add the token to the preamble */
 565         g_strlcpy(&packet_preamble[packet_preamble_len], str, PACKET_PREAMBLE_MAX_LEN);
 566         packet_preamble_len += (int) toklen;
 567         if (debug >= 2) {
 568             char *c;
 569             char xs[PACKET_PREAMBLE_MAX_LEN];
 570             g_strlcpy(xs, packet_preamble, PACKET_PREAMBLE_MAX_LEN);
 571             while ((c = strchr(xs, '\r')) != NULL) *c=' ';
 572             fprintf (stderr, "[[append_to_preamble: \"%s\"]]", xs);
 573         }
 574     }
 575 }
 576
 577 /*----------------------------------------------------------------------
 578  * Parse the preamble to get the timecode.
 579  */
 580
 581 static void
 582 parse_preamble (void)
 583 {
 584     struct tm timecode;
 585     char *subsecs;
 586     char *p;
 587     int  subseclen;
 588     int  i;
 589
 590     /*
 591      * Null-terminate the preamble.
 592      */
 593     packet_preamble[packet_preamble_len] = '\0';
 594
 595     if (has_direction) {
 596         switch (packet_preamble[0]) {
 597         case 'i':
 598         case 'I':
 599             direction = 0x00000001;
 600             packet_preamble[0] = ' ';
 601             break;
 602         case 'o':
 603         case 'O':
 604             direction = 0x00000002;
 605             packet_preamble[0] = ' ';
 606             break;
 607         default:
 608             direction = 0x00000000;
 609             break;
 610         }
 611         i = 0;
 612         while (packet_preamble[i] == ' ' ||
 613                packet_preamble[i] == '\r' ||
 614                packet_preamble[i] == '\t') {
 615             i++;
 616         }
 617         packet_preamble_len -= i;
 618         /* Also move the trailing '\0'. */
 619         memmove(packet_preamble, packet_preamble + i, packet_preamble_len + 1);
 620     }
 621
 622     /*
 623      * If no "-t" flag was specified, don't attempt to parse a packet
 624      * preamble to extract a time stamp.
 625      */
 626     if (ts_fmt == NULL)
 627         return;
 628
 629     /*
 630      * Initialize to today localtime, just in case not all fields
 631      * of the date and time are specified.
 632      */
 633
 634     timecode = timecode_default;
 635     ts_usec = 0;
 636
 637     /* Ensure preamble has more than two chars before atempting to parse.
 638      * This should cover line breaks etc that get counted.
 639      */
 640     if ( strlen(packet_preamble) > 2 ) {
 641         /* Get Time leaving subseconds */
 642         subsecs = strptime( packet_preamble, ts_fmt, &timecode );
 643         if (subsecs != NULL) {
 644             /* Get the long time from the tm structure */
 645             /*  (will return -1 if failure)            */
 646             ts_sec  = mktime( &timecode );
 647         } else
 648             ts_sec = -1;    /* we failed to parse it */
 649
 650         /* This will ensure incorrectly parsed dates get set to zero */
 651         if ( -1 == ts_sec )
 652         {
 653             /* Sanitize - remove all '\r' */
 654             char *c;
 655             while ((c = strchr(packet_preamble, '\r')) != NULL) *c=' ';
 656             fprintf (stderr, "Failure processing time \"%s\" using time format \"%s\"\n   (defaulting to Jan 1,1970 00:00:00 GMT)\n",
 657                  packet_preamble, ts_fmt);
 658             if (debug >= 2) {
 659                 fprintf(stderr, "timecode: %02d/%02d/%d %02d:%02d:%02d %d\n",
 660                     timecode.tm_mday, timecode.tm_mon, timecode.tm_year,
 661                     timecode.tm_hour, timecode.tm_min, timecode.tm_sec, timecode.tm_isdst);
 662             }
 663             ts_sec  = 0;  /* Jan 1,1970: 00:00 GMT; tshark/wireshark will display date/time as adjusted by timezone */
 664             ts_usec = 0;
 665         }
 666         else
 667         {
 668             /* Parse subseconds */
 669             ts_usec = (guint32)strtol(subsecs, &p, 10);
 670             if (subsecs == p) {
 671                 /* Error */
 672                 ts_usec = 0;
 673             } else {
 674                 /*
 675                  * Convert that number to a number
 676                  * of microseconds; if it's N digits
 677                  * long, it's in units of 10^(-N) seconds,
 678                  * so, to convert it to units of
 679                  * 10^-6 seconds, we multiply by
 680                  * 10^(6-N).
 681                  */
 682                 subseclen = (int) (p - subsecs);
 683                 if (subseclen > 6) {
 684                     /*
 685                      * *More* than 6 digits; 6-N is
 686                      * negative, so we divide by
 687                      * 10^(N-6).
 688                      */
 689                     for (i = subseclen - 6; i != 0; i--)
 690                         ts_usec /= 10;
 691                 } else if (subseclen < 6) {
 692                     for (i = 6 - subseclen; i != 0; i--)
 693                         ts_usec *= 10;
 694                 }
 695             }
 696         }
 697     }
 698     if (debug >= 2) {
 699         char *c;
 700         while ((c = strchr(packet_preamble, '\r')) != NULL) *c=' ';
 701         fprintf(stderr, "[[parse_preamble: \"%s\"]]\n", packet_preamble);
 702         fprintf(stderr, "Format(%s), time(%u), subsecs(%u)\n", ts_fmt, (guint32)ts_sec, ts_usec);
 703     }
 704
 705
 706     /* Clear Preamble */
 707     packet_preamble_len = 0;
 708 }
 709
 710 /*----------------------------------------------------------------------
 711  * Start a new packet
 712  */
 713 static void
 714 start_new_packet (void)
 715 {
 716     if (debug>=1)
 717         fprintf(stderr, "Start new packet\n");
 718
 719     /* Write out the current packet, if required */
 720     write_current_packet();
 721
 722     /* Ensure we parse the packet preamble as it may contain the time */
 723     parse_preamble();
 724 }
 725
 726 /*----------------------------------------------------------------------
 727  * Process a directive
 728  */
 729 static void
 730 process_directive (char *str)
 731 {
 732     fprintf(stderr, "\n--- Directive [%s] currently unsupported ---\n", str+10);
 733
 734 }
 735
 736 /*----------------------------------------------------------------------
 737  * Parse a single token (called from the scanner)
 738  */
 739 void
 740 parse_token (token_t token, char *str)
 741 {
 742     guint32 num;
 743
 744     /*
 745      * This is implemented as a simple state machine of five states.
 746      * State transitions are caused by tokens being received from the
 747      * scanner. The code should be self_documenting.
 748      */
 749
 750     if (debug>=2) {
 751         /* Sanitize - remove all '\r' */
 752         char *c;
 753         if (str!=NULL) { while ((c = strchr(str, '\r')) != NULL) *c=' '; }
 754
 755         fprintf(stderr, "(%s, %s \"%s\") -> (",
 756                 state_str[state], token_str[token], str ? str : "");
 757     }
 758
 759     switch(state) {
 760
 761     /* ----- Waiting for new packet -------------------------------------------*/
 762     case INIT:
 763         switch(token) {
 764         case T_TEXT:
 765             append_to_preamble(str);
 766             break;
 767         case T_DIRECTIVE:
 768             process_directive(str);
 769             break;
 770         case T_OFFSET:
 771             num = parse_num(str, TRUE);
 772             if (num==0) {
 773                 /* New packet starts here */
 774                 start_new_packet();
 775                 state = READ_OFFSET;
 776             }
 777             break;
 778         default:
 779             break;
 780         }
 781         break;
 782
 783     /* ----- Processing packet, start of new line -----------------------------*/
 784     case START_OF_LINE:
 785         switch(token) {
 786         case T_TEXT:
 787             append_to_preamble(str);
 788             break;
 789         case T_DIRECTIVE:
 790             process_directive(str);
 791             break;
 792         case T_OFFSET:
 793             num = parse_num(str, TRUE);
 794             if (num==0) {
 795                 /* New packet starts here */
 796                 start_new_packet();
 797                 packet_start = 0;
 798                 state = READ_OFFSET;
 799             } else if ((num - packet_start) != curr_offset) {
 800                 /*
 801                  * The offset we read isn't the one we expected.
 802                  * This may only mean that we mistakenly interpreted
 803                  * some text as byte values (e.g., if the text dump
 804                  * of packet data included a number with spaces around
 805                  * it).  If the offset is less than what we expected,
 806                  * assume that's the problem, and throw away the putative
 807                  * extra byte values.
 808                  */
 809                 if (num < curr_offset) {
 810                     unwrite_bytes(curr_offset - num);
 811                     state = READ_OFFSET;
 812                 } else {
 813                     /* Bad offset; switch to INIT state */
 814                     if (debug>=1)
 815                         fprintf(stderr, "Inconsistent offset. Expecting %0X, got %0X. Ignoring rest of packet\n",
 816                                 curr_offset, num);
 817                     write_current_packet();
 818                     state = INIT;
 819                 }
 820             } else
 821                 state = READ_OFFSET;
 822             break;
 823         default:
 824             break;
 825         }
 826         break;
 827
 828     /* ----- Processing packet, read offset -----------------------------------*/
 829     case READ_OFFSET:
 830         switch(token) {
 831         case T_BYTE:
 832             /* Record the byte */
 833             state = READ_BYTE;
 834             write_byte(str);
 835             break;
 836         case T_TEXT:
 837         case T_DIRECTIVE:
 838         case T_OFFSET:
 839             state = READ_TEXT;
 840             break;
 841         case T_EOL:
 842             state = START_OF_LINE;
 843             break;
 844         default:
 845             break;
 846         }
 847         break;
 848
 849     /* ----- Processing packet, read byte -------------------------------------*/
 850     case READ_BYTE:
 851         switch(token) {
 852         case T_BYTE:
 853             /* Record the byte */
 854             write_byte(str);
 855             break;
 856         case T_TEXT:
 857         case T_DIRECTIVE:
 858         case T_OFFSET:
 859             state = READ_TEXT;
 860             break;
 861         case T_EOL:
 862             state = START_OF_LINE;
 863             break;
 864         default:
 865             break;
 866         }
 867         break;
 868
 869     /* ----- Processing packet, read text -------------------------------------*/
 870     case READ_TEXT:
 871         switch(token) {
 872         case T_EOL:
 873             state = START_OF_LINE;
 874             break;
 875         default:
 876             break;
 877         }
 878         break;
 879
 880     default:
 881         fprintf(stderr, "FATAL ERROR: Bad state (%d)", state);
 882         exit(-1);
 883     }
 884
 885     if (debug>=2)
 886         fprintf(stderr, ", %s)\n", state_str[state]);
 887
 888 }
 889
 890 /*----------------------------------------------------------------------
 891  * take in the import config information
 892  */
 893 void
 894 text_import_setup(text_import_info_t *info)
 895 {
 896     packet_buf = (guint8 *)g_malloc(sizeof(HDR_ETHERNET) + sizeof(HDR_IP) +
 897                                     sizeof(HDR_SCTP) + sizeof(HDR_DATA_CHUNK) +
 898                                     IMPORT_MAX_PACKET);
 899
 900     if (!packet_buf)
 901     {
 902         fprintf(stderr, "FATAL ERROR: no memory for packet buffer");
 903         exit(-1);
 904     }
 905
 906     /* Lets start from the beginning */
 907     state = INIT;
 908     curr_offset = 0;
 909     packet_start = 0;
 910     packet_preamble_len = 0;
 911     ts_sec = time(0);            /* initialize to current time */
 912     timecode_default = *localtime(&ts_sec);
 913     timecode_default.tm_isdst = -1;     /* Unknown for now, depends on time given to the strptime() function */
 914     ts_usec = 0;
 915
 916     /* Dummy headers */
 917     hdr_ethernet = FALSE;
 918     hdr_ip = FALSE;
 919     hdr_udp = FALSE;
 920     hdr_tcp = FALSE;
 921     hdr_sctp = FALSE;
 922     hdr_data_chunk = FALSE;
 923
 924     offset_base = (info->offset_type == OFFSET_HEX) ? 16 :
 925                   (info->offset_type == OFFSET_OCT) ? 8 :
 926                   (info->offset_type == OFFSET_DEC) ? 10 :
 927                   16;
 928
 929     has_direction = info->has_direction;
 930
 931     if (info->date_timestamp)
 932     {
 933         ts_fmt = info->date_timestamp_format;
 934     }
 935
 936     pcap_link_type = info->encapsulation;
 937
 938     wdh = info->wdh;
 939
 940     switch (info->dummy_header_type)
 941     {
 942         case HEADER_ETH:
 943             hdr_ethernet = TRUE;
 944             hdr_ethernet_proto = info->pid;
 945             break;
 946
 947         case HEADER_IPV4:
 948             hdr_ip = TRUE;
 949             hdr_ip_proto = info->protocol;
 950             hdr_ethernet = TRUE;
 951             hdr_ethernet_proto = 0x800;
 952             break;
 953
 954         case HEADER_UDP:
 955             hdr_udp = TRUE;
 956             hdr_tcp = FALSE;
 957             hdr_src_port = info->src_port;
 958             hdr_dest_port = info->dst_port;
 959             hdr_ip = TRUE;
 960             hdr_ip_proto = 17;
 961             hdr_ethernet = TRUE;
 962             hdr_ethernet_proto = 0x800;
 963             break;
 964
 965         case HEADER_TCP:
 966             hdr_tcp = TRUE;
 967             hdr_udp = FALSE;
 968             hdr_src_port = info->src_port;
 969             hdr_dest_port = info->dst_port;
 970             hdr_ip = TRUE;
 971             hdr_ip_proto = 6;
 972             hdr_ethernet = TRUE;
 973             hdr_ethernet_proto = 0x800;
 974             break;
 975
 976         case HEADER_SCTP:
 977             hdr_sctp = TRUE;
 978             hdr_sctp_src = info->src_port;
 979             hdr_sctp_dest = info->dst_port;
 980             hdr_sctp_tag = info->tag;
 981             hdr_ip = TRUE;
 982             hdr_ip_proto = 132;
 983             hdr_ethernet = TRUE;
 984             hdr_ethernet_proto = 0x800;
 985             break;
 986
 987         case HEADER_SCTP_DATA:
 988             hdr_sctp = TRUE;
 989             hdr_data_chunk = TRUE;
 990             hdr_sctp_src = info->src_port;
 991             hdr_sctp_dest = info->dst_port;
 992             hdr_data_chunk_ppid = info->ppi;
 993             hdr_ip = TRUE;
 994             hdr_ip_proto = 132;
 995             hdr_ethernet = TRUE;
 996             hdr_ethernet_proto = 0x800;
 997             break;
 998
 999         default:
1000             break;
1001     }
1002
1003     max_offset = info->max_frame_length;
1004 }
1005
1006 /*----------------------------------------------------------------------
1007  * Clean up after text import
1008  */
1009 void
1010 text_import_cleanup(void)
1011 {
1012     g_free(packet_buf);
1013 }
1014
1015 /*
1016  * Editor modelines
1017  *
1018  * Local Variables:
1019  * c-basic-offset: 4
1020  * tab-width: 8
1021  * indent-tabs-mode: nil
1022  * End:
1023  *
1024  * ex: set shiftwidth=4 tabstop=8 expandtab:
1025  * :indentSize=4:tabSize=8:noTabs=true:
1026  */