wiretap/daintree-sna.c

   1 /* daintree_sna.c
   2  * Routines for opening .dcf capture files created by Daintree's
   3  * Sensor Network Analyzer for 802.15.4 radios
   4  * Copyright 2009, Exegin Technologies Limited <fff@exegin.com>
   5  *
   6  * $Id$
   7  *
   8  * Wireshark - Network traffic analyzer
   9  * By Gerald Combs <gerald@wireshark.org>
  10  * Copyright 1998 Gerald Combs
  11  *
  12  * Started with packetlogger.c as a template, but little packetlogger code
  13  * remains. Borrowed many snippets from dbs-etherwatch.c, the
  14  * daintree_sna_process_hex_data function having the largest chunk.
  15  *
  16  * This program is free software; you can redistribute it and/or
  17  * modify it under the terms of the GNU General Public License
  18  * as published by the Free Software Foundation; either version 2
  19  * of the License, or (at your option) any later version.
  20  *
  21  * This program is distributed in the hope that it will be useful,
  22  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  23  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  24  * GNU General Public License for more details.
  25  *
  26  * You should have received a copy of the GNU General Public License
  27  * along with this program; if not, write to the Free Software
  28  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
  29  * USA.
  30  */
  31
  32 /* This module reads capture files saved by Daintree's Sensor Network Analyzer.
  33  * Daintree captures are plain text files with a two line header,
  34  * followed by packet records, one per line, with whitespace separated fields
  35  * consisting of: packet number, time, bytes of capture data, capture data,
  36  * unknown, unknown, signal strength?, unknown, etc, and terminated with CRLF.
  37  */
  38
  39 /* Example capture file:
  40
  41 #Format=4
  42 # SNA v2.2.0.4 SUS:20090709 ACT:819705
  43 1 1233783799.326400 10 030809ffffffff07ffff 42 1 -69 25 2 0 1 32767
  44 2 1233783799.477440 5 02000bffff 110 1 -44 25 6 0 1 32767
  45 3 1233783799.809920 5 020013ffff 107 1 -45 25 43 0 1 3276
  46
  47 */
  48
  49 #include "config.h"
  50
  51 #include <glib.h>
  52 #include <stdio.h>
  53 #include <stdlib.h>
  54 #include <errno.h>
  55 #include <string.h>
  56 #include <ctype.h>
  57
  58 #include "wtap.h"
  59 #include "wtap-int.h"
  60 #include "buffer.h"
  61 #include "file_wrappers.h"
  62 #include "daintree-sna.h"
  63
  64 typedef struct daintree_sna_header {
  65         guint32 len;
  66         guint64 ts;
  67 } daintree_sna_header_t;
  68
  69 #define DAINTREE_SNA_HEADER_SIZE 2
  70 #define FCS_LENGTH 2
  71
  72 static const char daintree_magic_text[] =
  73 { '#', 'F', 'o', 'r', 'm', 'a', 't', '=' };
  74
  75 #define DAINTREE_MAGIC_TEXT_SIZE (sizeof daintree_magic_text)
  76 #define DAINTREE_MAX_LINE_SIZE 512
  77 #define READDATA_BUF_SIZE (DAINTREE_MAX_LINE_SIZE/2)
  78 #define READDATA_MAX_FIELD_SIZE "255"  /* DAINTREE_MAX_LINE_SIZE/2 -1 */
  79
  80 #define COMMENT_LINE daintree_magic_text[0]
  81
  82 static gboolean daintree_sna_read(wtap *wth, int *err, gchar **err_info,
  83         gint64 *data_offset);
  84
  85 static gboolean daintree_sna_seek_read(wtap *wth, gint64 seek_off,
  86         struct wtap_pkthdr *phdr, Buffer *buf, int len, int *err,
  87         gchar **err_info);
  88
  89 static gboolean daintree_sna_scan_header(struct wtap_pkthdr *phdr,
  90         char *readLine, char *readData, int *err, gchar **err_info);
  91
  92 static gboolean daintree_sna_process_hex_data(struct wtap_pkthdr *phdr,
  93         Buffer *buf, char *readData, int *err, gchar **err_info);
  94
  95 /* Open a file and determine if it's a Daintree file */
  96 int daintree_sna_open(wtap *wth, int *err, gchar **err_info)
  97 {
  98         char readLine[DAINTREE_MAX_LINE_SIZE];
  99         guint i;
 100
 101         /* get first line of file header */
 102         if (file_gets(readLine, DAINTREE_MAX_LINE_SIZE, wth->fh)==NULL) {
 103                 *err = file_error(wth->fh, err_info);
 104                 if (*err != 0 && *err != WTAP_ERR_SHORT_READ)
 105                         return -1;
 106                 return 0;
 107         }
 108
 109         /* check magic text */
 110         i = 0;
 111         while (i < DAINTREE_MAGIC_TEXT_SIZE) {
 112                 if (readLine[i] != daintree_magic_text[i]) return 0; /* not daintree format */
 113                 i++;
 114         }
 115
 116         /* read second header line */
 117         if (file_gets(readLine, DAINTREE_MAX_LINE_SIZE, wth->fh)==NULL) {
 118                 *err = file_error(wth->fh, err_info);
 119                 if (*err != 0 && *err != WTAP_ERR_SHORT_READ)
 120                         return -1;
 121                 return 0;
 122         }
 123         if (readLine[0] != COMMENT_LINE) return 0; /* daintree files have a two line header */
 124
 125         /* set up the pointers to the handlers for this file type */
 126         wth->subtype_read = daintree_sna_read;
 127         wth->subtype_seek_read = daintree_sna_seek_read;
 128
 129         /* set up for file type */
 130         wth->file_type_subtype = WTAP_FILE_TYPE_SUBTYPE_DAINTREE_SNA;
 131         wth->file_encap = WTAP_ENCAP_IEEE802_15_4_NOFCS;
 132         wth->tsprecision = WTAP_FILE_TSPREC_USEC;
 133         wth->snapshot_length = 0; /* not available in header */
 134
 135         return 1; /* it's a Daintree file */
 136 }
 137
 138 /* Read the capture file sequentially
 139  * Wireshark scans the file with sequential reads during preview and initial display. */
 140 static gboolean
 141 daintree_sna_read(wtap *wth, int *err, gchar **err_info, gint64 *data_offset)
 142 {
 143         char readLine[DAINTREE_MAX_LINE_SIZE];
 144         char readData[READDATA_BUF_SIZE];
 145
 146         *data_offset = file_tell(wth->fh);
 147
 148         /* we've only seen file header lines starting with '#', but
 149          * if others appear in the file, they are tossed */
 150         do {
 151                 if (file_gets(readLine, DAINTREE_MAX_LINE_SIZE, wth->fh) == NULL) {
 152                         *err = file_error(wth->fh, err_info);
 153                         return FALSE; /* all done */
 154                 }
 155         } while (readLine[0] == COMMENT_LINE);
 156
 157         /* parse one line of capture data */
 158         if (!daintree_sna_scan_header(&wth->phdr, readLine, readData,
 159             err, err_info))
 160                 return FALSE;
 161
 162         /* process packet data */
 163         return daintree_sna_process_hex_data(&wth->phdr, wth->frame_buffer,
 164             readData, err, err_info);
 165 }
 166
 167 /* Read the capture file randomly
 168  * Wireshark opens the capture file for random access when displaying user-selected packets */
 169 static gboolean
 170 daintree_sna_seek_read(wtap *wth, gint64 seek_off, struct wtap_pkthdr *phdr,
 171         Buffer *buf, int len _U_, int *err, gchar **err_info)
 172 {
 173         char readLine[DAINTREE_MAX_LINE_SIZE];
 174         char readData[READDATA_BUF_SIZE];
 175
 176         if(file_seek(wth->random_fh, seek_off, SEEK_SET, err) == -1)
 177                 return FALSE;
 178
 179         /* It appears only file header lines start with '#', but
 180          * if we find any others, we toss them */
 181         do {
 182                 if (file_gets(readLine, DAINTREE_MAX_LINE_SIZE, wth->random_fh) == NULL) {
 183                         *err = file_error(wth->random_fh, err_info);
 184                         return FALSE; /* all done */
 185                 }
 186         } while (readLine[0] == COMMENT_LINE);
 187
 188         /* parse one line of capture data */
 189         if (!daintree_sna_scan_header(phdr, readLine, readData, err, err_info))
 190                 return FALSE;
 191
 192         /* process packet data */
 193         return daintree_sna_process_hex_data(phdr, buf, readData, err,
 194             err_info);
 195 }
 196
 197 /* Scan a header line and fill in a struct wtap_pkthdr */
 198 static gboolean
 199 daintree_sna_scan_header(struct wtap_pkthdr *phdr, char *readLine,
 200     char *readData, int *err, gchar **err_info)
 201 {
 202         guint64 seconds;
 203         int useconds;
 204
 205         phdr->presence_flags = WTAP_HAS_TS|WTAP_HAS_CAP_LEN;
 206
 207         if (sscanf(readLine, "%*s %18" G_GINT64_MODIFIER "u.%9d %9u %" READDATA_MAX_FIELD_SIZE "s",
 208             &seconds, &useconds, &phdr->len, readData) != 4) {
 209                 *err = WTAP_ERR_BAD_FILE;
 210                 *err_info = g_strdup("daintree_sna: invalid read record");
 211                 return FALSE;
 212         }
 213
 214         /* Daintree doesn't store the FCS, but pads end of packet with 0xffff, which we toss */
 215         if (phdr->len <= FCS_LENGTH) {
 216                 *err = WTAP_ERR_BAD_FILE;
 217                 *err_info = g_strdup_printf("daintree_sna: packet length <= %u bytes, no frame data present",
 218                     FCS_LENGTH);
 219                 return FALSE;
 220         }
 221         phdr->len -= FCS_LENGTH;
 222
 223         phdr->ts.secs = (time_t) seconds;
 224         phdr->ts.nsecs = useconds * 1000; /* convert mS to nS */
 225
 226         return TRUE;
 227 }
 228
 229 /* Convert packet data from ASCII hex string to binary in place,
 230  * sanity-check its length against what we assume is the packet length field,
 231  * and copy it into a Buffer */
 232 static gboolean
 233 daintree_sna_process_hex_data(struct wtap_pkthdr *phdr, Buffer *buf,
 234     char *readData, int *err, gchar **err_info)
 235 {
 236         guchar *str = (guchar *)readData;
 237         guint bytes;
 238         guint8 *p;
 239
 240         p = str; /* overlay source buffer */
 241         bytes = 0;
 242         /* convert hex string to guint8 */
 243         while(*str) {
 244                 /* most significant nibble */
 245                 if (!isxdigit((guchar)*str)) {
 246                         *err = WTAP_ERR_BAD_FILE;
 247                         *err_info = g_strdup("daintree_sna: non-hex digit in hex data");
 248                         return FALSE;
 249                 }
 250                 if(isdigit((guchar)*str)) {
 251                         *p = (*str - '0') << 4;
 252                 } else {
 253                         *p = ((tolower(*str) - 'a') + 10) << 4;
 254                 }
 255                 str++;
 256
 257                 /* least significant nibble */
 258                 if (!isxdigit((guchar)*str)) {
 259                         *err = WTAP_ERR_BAD_FILE;
 260                         *err_info = g_strdup("daintree_sna: non-hex digit in hex data");
 261                         return FALSE;
 262                 }
 263                 if(isdigit((guchar)*str)) {
 264                         *p += *str - '0';
 265                 } else {
 266                         *p += (tolower(*str) - 'a') + 10;
 267                 }
 268                 str++;
 269
 270                 /* next byte in buffer */
 271                 p++;
 272                 bytes++;
 273         }
 274
 275         /* Daintree doesn't store the FCS, but pads end of packet with 0xffff, which we toss */
 276         if (bytes <= FCS_LENGTH) {
 277                 *err = WTAP_ERR_BAD_FILE;
 278                 *err_info = g_strdup_printf("daintree_sna: Only %u bytes of packet data",
 279                     bytes);
 280                 return FALSE;
 281         }
 282         bytes -= FCS_LENGTH;
 283         if (bytes > phdr->len) {
 284                 *err = WTAP_ERR_BAD_FILE;
 285                 *err_info = g_strdup_printf("daintree_sna: capture length (%u) > packet length (%u)",
 286                     bytes, phdr->len);
 287                 return FALSE;
 288         }
 289
 290         phdr->caplen = bytes;
 291
 292         buffer_assure_space(buf, bytes);
 293         memcpy(buffer_start_ptr(buf), readData, bytes);
 294         return TRUE;
 295 }