nexmon – Rev 1
?pathlinks?
/* dct3trace.c
* Routines for reading signalling traces generated by Gammu (www.gammu.org)
* from Nokia DCT3 phones in Netmonitor mode.
*
* gammu --nokiadebug nhm5_587.txt v18-19
*
* Duncan Salerno <duncan.salerno@googlemail.com>
*
* Wiretap Library
* Copyright (c) 1998 by Gilbert Ramirez <gram@alumni.rice.edu>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include "config.h"
#include "wtap-int.h"
#include "dct3trace.h"
#include "file_wrappers.h"
#include <stdlib.h>
#include <string.h>
/*
Example downlink data:
<?xml version="1.0"?>
<dump>
<l1 direction="down" logicalchannel="96" physicalchannel="19" sequence="268116" error="0" timeshift="2992" bsic="22" data="31063F100DD0297A53E1020103C802398E0B2B2B2B2B2B" >
<l2 data="063F100DD0297A53E1020103" rest="C802398E0B2B2B2B2B2B" >
</l2>
</l1>
</dump>
Example uplink data (no raw L1):
<?xml version="1.0"?>
<dump>
<l1 direction="up" logicalchannel="112" >
<l2 type="U" subtype="Unknown" p="0" data="061500400000000000000000000000000000" >
</l2>
</l1>
</dump>
*/
/* Magic text to check */
static const char dct3trace_magic_line1[] = "<?xml version=\"1.0\"?>";
static const char dct3trace_magic_line2[] = "<dump>";
static const char dct3trace_magic_record_start[] = "<l1 ";
static const char dct3trace_magic_record_end[] = "</l1>";
static const char dct3trace_magic_l2_start[] = "<l2 ";
#if 0 /* Not used ?? */
static const char dct3trace_magic_l2_end[] = "</l2>";
#endif
static const char dct3trace_magic_end[] = "</dump>";
#define MAX_PACKET_LEN 23
static gboolean dct3trace_read(wtap *wth, int *err, gchar **err_info,
gint64 *data_offset);
static gboolean dct3trace_seek_read(wtap *wth, gint64 seek_off,
struct wtap_pkthdr *phdr, Buffer *buf, int *err, gchar **err_info);
/*
* Following 3 functions taken from gsmdecode-0.7bis, with permission - http://wiki.thc.org/gsm
*/
static int
hc2b(unsigned char hex)
{
hex = g_ascii_tolower(hex);
if ((hex >= '0') && (hex <= '9'))
return hex - '0';
if ((hex >= 'a') && (hex <= 'f'))
return hex - 'a' + 10;
return -1;
}
static int
hex2bin(guint8 *out, guint8 *out_end, char *in)
{
guint8 *out_start = out;
int is_low = 0;
int c;
while (*in != '\0')
{
c = hc2b(*(unsigned char *)in);
if (c < 0)
{
in++;
continue;
}
if (out == out_end)
{
/* Too much data */
return -1;
}
if (is_low == 0)
{
*out = c << 4;
is_low = 1;
} else {
*out |= (c & 0x0f);
is_low = 0;
out++;
}
in++;
}
return (int)(out - out_start);
}
static int
xml_get_int(int *val, const char *str, const char *pattern)
{
const char *ptr;
char *start, *end;
char buf[32];
ptr = strstr(str, pattern);
if (ptr == NULL)
return -1;
start = strchr(ptr, '"');
if (start == NULL)
return -2;
start++;
end = strchr(start, '"');
if (end == NULL)
return -3;
if (end - start > 31)
return -4;
memcpy(buf, start, end - start);
buf[end - start] = '\0';
*val = atoi(buf);
return 0;
}
wtap_open_return_val dct3trace_open(wtap *wth, int *err, gchar **err_info)
{
char line1[64], line2[64];
/* Look for Gammu DCT3 trace header */
if (file_gets(line1, sizeof(line1), wth->fh) == NULL ||
file_gets(line2, sizeof(line2), wth->fh) == NULL)
{
*err = file_error(wth->fh, err_info);
if (*err != 0 && *err != WTAP_ERR_SHORT_READ)
return WTAP_OPEN_ERROR;
return WTAP_OPEN_NOT_MINE;
}
/* Don't compare line endings */
if( strncmp(dct3trace_magic_line1, line1, strlen(dct3trace_magic_line1)) != 0 ||
strncmp(dct3trace_magic_line2, line2, strlen(dct3trace_magic_line2)) != 0)
{
return WTAP_OPEN_NOT_MINE;
}
wth->file_encap = WTAP_ENCAP_GSM_UM;
wth->file_type_subtype = WTAP_FILE_TYPE_SUBTYPE_DCT3TRACE;
wth->snapshot_length = 0; /* not known */
wth->subtype_read = dct3trace_read;
wth->subtype_seek_read = dct3trace_seek_read;
wth->file_tsprec = WTAP_TSPREC_SEC;
return WTAP_OPEN_MINE;
}
static gboolean dct3trace_get_packet(FILE_T fh, struct wtap_pkthdr *phdr,
Buffer *buf, int *err, gchar **err_info)
{
char line[1024];
guint8 databuf[MAX_PACKET_LEN], *bufp;
gboolean have_data = FALSE;
int len = 0;
bufp = &databuf[0];
while (file_gets(line, sizeof(line), fh) != NULL)
{
if( memcmp(dct3trace_magic_end, line, strlen(dct3trace_magic_end)) == 0 )
{
/* Return on end of file </dump> */
*err = 0;
return FALSE;
}
else if( memcmp(dct3trace_magic_record_end, line, strlen(dct3trace_magic_record_end)) == 0 )
{
/* Return on end of record </l1> */
if( have_data )
{
/* We've got a full packet! */
phdr->rec_type = REC_TYPE_PACKET;
phdr->presence_flags = 0; /* no time stamp, no separate "on the wire" length */
phdr->ts.secs = 0;
phdr->ts.nsecs = 0;
phdr->caplen = len;
phdr->len = len;
*err = 0;
/* Make sure we have enough room for the packet */
ws_buffer_assure_space(buf, phdr->caplen);
memcpy( ws_buffer_start_ptr(buf), databuf, phdr->caplen );
return TRUE;
}
else
{
/* If not got any data return error */
*err = WTAP_ERR_BAD_FILE;
*err_info = g_strdup("dct3trace: record without data");
return FALSE;
}
}
else if( memcmp(dct3trace_magic_record_start, line, strlen(dct3trace_magic_record_start)) == 0 )
{
/* Parse L1 header <l1 ...>*/
int channel, tmp;
char *ptr;
phdr->pseudo_header.gsm_um.uplink = !strstr(line, "direction=\"down\"");
if (xml_get_int(&channel, line, "logicalchannel") != 0)
goto baddata;
/* Parse downlink only fields */
if( !phdr->pseudo_header.gsm_um.uplink )
{
if (xml_get_int(&tmp, line, "physicalchannel") != 0)
goto baddata;
phdr->pseudo_header.gsm_um.arfcn = tmp;
if (xml_get_int(&tmp, line, "sequence") != 0)
goto baddata;
phdr->pseudo_header.gsm_um.tdma_frame = tmp;
if (xml_get_int(&tmp, line, "bsic") != 0)
goto baddata;
phdr->pseudo_header.gsm_um.bsic = tmp;
if (xml_get_int(&tmp, line, "error") != 0)
goto baddata;
phdr->pseudo_header.gsm_um.error = tmp;
if (xml_get_int(&tmp, line, "timeshift") != 0)
goto baddata;
phdr->pseudo_header.gsm_um.timeshift = tmp;
}
switch( channel )
{
case 128: phdr->pseudo_header.gsm_um.channel = GSM_UM_CHANNEL_SDCCH; break;
case 112: phdr->pseudo_header.gsm_um.channel = GSM_UM_CHANNEL_SACCH; break;
case 176: phdr->pseudo_header.gsm_um.channel = GSM_UM_CHANNEL_FACCH; break;
case 96: phdr->pseudo_header.gsm_um.channel = GSM_UM_CHANNEL_CCCH; break;
case 80: phdr->pseudo_header.gsm_um.channel = GSM_UM_CHANNEL_BCCH; break;
default: phdr->pseudo_header.gsm_um.channel = GSM_UM_CHANNEL_UNKNOWN; break;
}
/* Read data (if have it) into databuf */
ptr = strstr(line, "data=\"");
if( ptr )
{
have_data = TRUE; /* If has data... */
len = hex2bin(bufp, &databuf[MAX_PACKET_LEN], ptr+6);
if (len == -1)
{
*err = WTAP_ERR_BAD_FILE;
*err_info = g_strdup_printf("dct3trace: record length %d too long", phdr->caplen);
return FALSE;
}
}
}
else if( !have_data && memcmp(dct3trace_magic_l2_start, line, strlen(dct3trace_magic_l2_start)) == 0 )
{
/* For uplink packets we might not get the raw L1, so have to recreate it from the L2 */
/* Parse L2 header if didn't get data from L1 <l2 ...> */
int data_len;
char *ptr = strstr(line, "data=\"");
if( !ptr )
{
continue;
}
have_data = TRUE;
/*
* We know we have no data already, so we know
* we have enough room for the header.
*/
if( phdr->pseudo_header.gsm_um.channel == GSM_UM_CHANNEL_SACCH || phdr->pseudo_header.gsm_um.channel == GSM_UM_CHANNEL_FACCH || phdr->pseudo_header.gsm_um.channel == GSM_UM_CHANNEL_SDCCH )
{
/* Add LAPDm B header */
memset(bufp, 0x1, 2);
len = 3;
}
else
{
/* Add LAPDm Bbis header */
len = 1;
}
bufp += len;
data_len = hex2bin(bufp, &databuf[MAX_PACKET_LEN], ptr+6);
if (data_len == -1)
{
*err = WTAP_ERR_BAD_FILE;
*err_info = g_strdup_printf("dct3trace: record length %d too long", phdr->caplen);
return FALSE;
}
len += data_len;
/* Add LAPDm length byte */
*(bufp - 1) = data_len << 2 | 0x1;
}
}
*err = file_error(fh, err_info);
if (*err == 0)
{
*err = WTAP_ERR_SHORT_READ;
}
return FALSE;
baddata:
*err = WTAP_ERR_BAD_FILE;
*err_info = g_strdup("dct3trace: record missing mandatory attributes");
return FALSE;
}
/* Find the next packet and parse it; called from wtap_read(). */
static gboolean dct3trace_read(wtap *wth, int *err, gchar **err_info,
gint64 *data_offset)
{
*data_offset = file_tell(wth->fh);
return dct3trace_get_packet(wth->fh, &wth->phdr, wth->frame_buffer,
err, err_info);
}
/* Used to read packets in random-access fashion */
static gboolean dct3trace_seek_read(wtap *wth, gint64 seek_off,
struct wtap_pkthdr *phdr, Buffer *buf, int *err, gchar **err_info)
{
if (file_seek(wth->random_fh, seek_off, SEEK_SET, err) == -1)
{
return FALSE;
}
return dct3trace_get_packet(wth->random_fh, phdr, buf, err, err_info);
}
/*
* Editor modelines - http://www.wireshark.org/tools/modelines.html
*
* Local variables:
* c-basic-offset: 8
* tab-width: 8
* indent-tabs-mode: t
* End:
*
* vi: set shiftwidth=8 tabstop=8 noexpandtab:
* :indentSize=8:tabSize=8:noTabs=false:
*/