wireshark/wiretap/eyesdn.c

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/* eyesdn.c
*
* Wiretap Library
* Copyright (c) 1998 by Gilbert Ramirez <gram@alumni.rice.edu>
*
* SPDX-License-Identifier: GPL-2.0-or-later
*/
#include "config.h"
#include "wtap-int.h"
#include "eyesdn.h"
#include "file_wrappers.h"
#include <stdlib.h>
#include <string.h>
#include <errno.h>
static int eyesdn_file_type_subtype = -1;
void register_eyesdn(void);
/* This module reads the output of the EyeSDN USB S0/E1 ISDN probes
* They store HDLC frames of D and B channels in a binary format
* The fileformat is
*
* 1-6 Byte: EyeSDN - Magic
* 7-n Byte: Frames
*
* Each Frame starts with the 0xff Flag byte
* - Bytes 0-2: timestamp (usec in network byte order)
* - Bytes 3-7: timestamp (40bits sec since 1970 in network byte order)
* - Byte 8: channel (0 for D channel, 1-30 for B1-B30)
* - Byte 9: Sender Bit 0(0 NT, 1 TE), Protocol in Bits 7:1, see enum
* - Byte 10-11: frame size in bytes
* - Byte 12-n: Frame Payload
*
* All multibyte values are represented in network byte order
* The frame is terminated with a flag character (0xff)
* bytes 0xff within a frame are escaped using the 0xfe escape character
* the byte following the escape character is decremented by two:
* so 0xfe 0xfd is actually a 0xff
* Characters that need to be escaped are 0xff and 0xfe
*/
static gboolean esc_read(FILE_T fh, guint8 *buf, int len, int *err, gchar **err_info)
{
int i;
int value;
for(i=0; i<len; i++) {
value=file_getc(fh);
if(value==-1) {
/* EOF or error */
*err=file_error(fh, err_info);
if(*err==0)
*err=WTAP_ERR_SHORT_READ;
return FALSE;
}
if(value==0xff) {
/* error !!, read into next frame */
*err=WTAP_ERR_BAD_FILE;
*err_info=g_strdup("eyesdn: No flag character seen in frame");
return FALSE;
}
if(value==0xfe) {
/* we need to escape */
value=file_getc(fh);
if(value==-1) {
/* EOF or error */
*err=file_error(fh, err_info);
if(*err==0)
*err=WTAP_ERR_SHORT_READ;
return FALSE;
}
value+=2;
}
buf[i]=value;
}
return TRUE;
}
/* Magic text to check for eyesdn-ness of file */
static const unsigned char eyesdn_hdr_magic[] =
{ 'E', 'y', 'e', 'S', 'D', 'N'};
#define EYESDN_HDR_MAGIC_SIZE sizeof(eyesdn_hdr_magic)
/* Size of a record header */
#define EYESDN_HDR_LENGTH 12
static gboolean eyesdn_read(wtap *wth, wtap_rec *rec, Buffer *buf,
int *err, gchar **err_info, gint64 *data_offset);
static gboolean eyesdn_seek_read(wtap *wth, gint64 seek_off,
wtap_rec *rec, Buffer *buf, int *err, gchar **err_info);
static int read_eyesdn_rec(FILE_T fh, wtap_rec *rec, Buffer* buf,
int *err, gchar **err_info);
/* Seeks to the beginning of the next packet, and returns the
byte offset. Returns -1 on failure, and sets "*err" to the error
and "*err_info" to null or an additional error string. */
static gint64 eyesdn_seek_next_packet(wtap *wth, int *err, gchar **err_info)
{
int byte;
gint64 cur_off;
while ((byte = file_getc(wth->fh)) != EOF) {
if (byte == 0xff) {
cur_off = file_tell(wth->fh);
if (cur_off == -1) {
/* Error. */
*err = file_error(wth->fh, err_info);
return -1;
}
return cur_off;
}
}
/* EOF or error. */
*err = file_error(wth->fh, err_info);
return -1;
}
wtap_open_return_val eyesdn_open(wtap *wth, int *err, gchar **err_info)
{
char magic[EYESDN_HDR_MAGIC_SIZE];
/* Look for eyesdn header */
if (!wtap_read_bytes(wth->fh, &magic, sizeof magic, err, err_info)) {
if (*err != WTAP_ERR_SHORT_READ)
return WTAP_OPEN_ERROR;
return WTAP_OPEN_NOT_MINE;
}
if (memcmp(magic, eyesdn_hdr_magic, EYESDN_HDR_MAGIC_SIZE) != 0)
return WTAP_OPEN_NOT_MINE;
wth->file_encap = WTAP_ENCAP_PER_PACKET;
wth->file_type_subtype = eyesdn_file_type_subtype;
wth->snapshot_length = 0; /* not known */
wth->subtype_read = eyesdn_read;
wth->subtype_seek_read = eyesdn_seek_read;
wth->file_tsprec = WTAP_TSPREC_USEC;
return WTAP_OPEN_MINE;
}
/* Find the next record and parse it; called from wtap_read(). */
static gboolean eyesdn_read(wtap *wth, wtap_rec *rec, Buffer *buf,
int *err, gchar **err_info, gint64 *data_offset)
{
gint64 offset;
/* Find the next record */
offset = eyesdn_seek_next_packet(wth, err, err_info);
if (offset < 1)
return FALSE;
*data_offset = offset;
/* Parse the record */
return read_eyesdn_rec(wth->fh, rec, buf, err, err_info);
}
/* Used to read packets in random-access fashion */
static gboolean
eyesdn_seek_read(wtap *wth, gint64 seek_off, wtap_rec *rec,
Buffer *buf, int *err, gchar **err_info)
{
if (file_seek(wth->random_fh, seek_off, SEEK_SET, err) == -1)
return FALSE;
return read_eyesdn_rec(wth->random_fh, rec, buf, err, err_info);
}
/* Parses a record. */
static gboolean
read_eyesdn_rec(FILE_T fh, wtap_rec *rec, Buffer *buf, int *err,
gchar **err_info)
{
union wtap_pseudo_header *pseudo_header = &rec->rec_header.packet_header.pseudo_header;
guint8 hdr[EYESDN_HDR_LENGTH];
time_t secs;
int usecs;
guint pkt_len;
guint8 channel, direction;
guint8 *pd;
/* Our file pointer should be at the summary information header
* for a packet. Read in that header and extract the useful
* information.
*/
if (!esc_read(fh, hdr, EYESDN_HDR_LENGTH, err, err_info))
return FALSE;
/* extract information from header */
usecs = pntoh24(&hdr[0]);
#ifdef TV64BITS
secs = hdr[3];
#else
secs = 0;
#endif
secs = (secs << 8) | hdr[4];
secs = (secs << 8) | hdr[5];
secs = (secs << 8) | hdr[6];
secs = (secs << 8) | hdr[7];
channel = hdr[8];
direction = hdr[9];
pkt_len = pntoh16(&hdr[10]);
switch(direction >> 1) {
default:
case EYESDN_ENCAP_ISDN: /* ISDN */
pseudo_header->isdn.uton = direction & 1;
pseudo_header->isdn.channel = channel;
if(channel) { /* bearer channels */
rec->rec_header.packet_header.pkt_encap = WTAP_ENCAP_ISDN; /* recognises PPP */
pseudo_header->isdn.uton=!pseudo_header->isdn.uton; /* bug */
} else { /* D channel */
rec->rec_header.packet_header.pkt_encap = WTAP_ENCAP_ISDN;
}
break;
case EYESDN_ENCAP_MSG: /* Layer 1 message */
rec->rec_header.packet_header.pkt_encap = WTAP_ENCAP_LAYER1_EVENT;
pseudo_header->l1event.uton = (direction & 1);
break;
case EYESDN_ENCAP_LAPB: /* X.25 via LAPB */
rec->rec_header.packet_header.pkt_encap = WTAP_ENCAP_LAPB;
pseudo_header->dte_dce.flags = (direction & 1) ? 0 : 0x80;
break;
case EYESDN_ENCAP_ATM: { /* ATM cells */
#define CELL_LEN 53
unsigned char cell[CELL_LEN];
gint64 cur_off;
if(pkt_len != CELL_LEN) {
*err = WTAP_ERR_BAD_FILE;
*err_info = ws_strdup_printf(
"eyesdn: ATM cell has a length != 53 (%u)",
pkt_len);
return FALSE;
}
cur_off = file_tell(fh);
if (!esc_read(fh, cell, CELL_LEN, err, err_info))
return FALSE;
if (file_seek(fh, cur_off, SEEK_SET, err) == -1)
return FALSE;
rec->rec_header.packet_header.pkt_encap = WTAP_ENCAP_ATM_PDUS_UNTRUNCATED;
pseudo_header->atm.flags=ATM_RAW_CELL;
pseudo_header->atm.aal=AAL_UNKNOWN;
pseudo_header->atm.type=TRAF_UMTS_FP;
pseudo_header->atm.subtype=TRAF_ST_UNKNOWN;
pseudo_header->atm.vpi=((cell[0]&0xf)<<4) + (cell[0]&0xf);
pseudo_header->atm.vci=((cell[0]&0xf)<<4) + cell[0]; /* from cell */
pseudo_header->atm.channel=direction & 1;
}
break;
case EYESDN_ENCAP_MTP2: /* SS7 frames */
pseudo_header->mtp2.sent = direction & 1;
pseudo_header->mtp2.annex_a_used = MTP2_ANNEX_A_USED_UNKNOWN;
pseudo_header->mtp2.link_number = channel;
rec->rec_header.packet_header.pkt_encap = WTAP_ENCAP_MTP2_WITH_PHDR;
break;
case EYESDN_ENCAP_DPNSS: /* DPNSS */
pseudo_header->isdn.uton = direction & 1;
pseudo_header->isdn.channel = channel;
rec->rec_header.packet_header.pkt_encap = WTAP_ENCAP_DPNSS;
break;
case EYESDN_ENCAP_DASS2: /* DASS2 frames */
pseudo_header->isdn.uton = direction & 1;
pseudo_header->isdn.channel = channel;
rec->rec_header.packet_header.pkt_encap = WTAP_ENCAP_DPNSS;
break;
case EYESDN_ENCAP_BACNET: /* BACNET async over HDLC frames */
pseudo_header->isdn.uton = direction & 1;
pseudo_header->isdn.channel = channel;
rec->rec_header.packet_header.pkt_encap = WTAP_ENCAP_BACNET_MS_TP_WITH_PHDR;
break;
case EYESDN_ENCAP_V5_EF: /* V5EF */
pseudo_header->isdn.uton = direction & 1;
pseudo_header->isdn.channel = channel;
rec->rec_header.packet_header.pkt_encap = WTAP_ENCAP_V5_EF;
break;
}
if(pkt_len > WTAP_MAX_PACKET_SIZE_STANDARD) {
*err = WTAP_ERR_BAD_FILE;
*err_info = ws_strdup_printf("eyesdn: File has %u-byte packet, bigger than maximum of %u",
pkt_len, WTAP_MAX_PACKET_SIZE_STANDARD);
return FALSE;
}
rec->rec_type = REC_TYPE_PACKET;
rec->block = wtap_block_create(WTAP_BLOCK_PACKET);
rec->presence_flags = WTAP_HAS_TS;
rec->ts.secs = secs;
rec->ts.nsecs = usecs * 1000;
rec->rec_header.packet_header.caplen = pkt_len;
rec->rec_header.packet_header.len = pkt_len;
/* Make sure we have enough room for the packet */
ws_buffer_assure_space(buf, pkt_len);
pd = ws_buffer_start_ptr(buf);
if (!esc_read(fh, pd, pkt_len, err, err_info))
return FALSE;
return TRUE;
}
static gboolean
esc_write(wtap_dumper *wdh, const guint8 *buf, int len, int *err)
{
int i;
guint8 byte;
static const guint8 esc = 0xfe;
for(i=0; i<len; i++) {
byte=buf[i];
if(byte == 0xff || byte == 0xfe) {
/*
* Escape the frame delimiter and escape byte.
*/
if (!wtap_dump_file_write(wdh, &esc, sizeof esc, err))
return FALSE;
byte-=2;
}
if (!wtap_dump_file_write(wdh, &byte, sizeof byte, err))
return FALSE;
}
return TRUE;
}
static gboolean eyesdn_dump(wtap_dumper *wdh,
const wtap_rec *rec,
const guint8 *pd, int *err, gchar **err_info);
static gboolean eyesdn_dump_open(wtap_dumper *wdh, int *err, gchar **err_info _U_)
{
wdh->subtype_write=eyesdn_dump;
if (!wtap_dump_file_write(wdh, eyesdn_hdr_magic,
EYESDN_HDR_MAGIC_SIZE, err))
return FALSE;
wdh->bytes_dumped += EYESDN_HDR_MAGIC_SIZE;
*err=0;
return TRUE;
}
static int eyesdn_dump_can_write_encap(int encap)
{
switch (encap) {
case WTAP_ENCAP_ISDN:
case WTAP_ENCAP_LAYER1_EVENT:
case WTAP_ENCAP_DPNSS:
case WTAP_ENCAP_ATM_PDUS_UNTRUNCATED:
case WTAP_ENCAP_LAPB:
case WTAP_ENCAP_MTP2_WITH_PHDR:
case WTAP_ENCAP_BACNET_MS_TP_WITH_PHDR:
case WTAP_ENCAP_PER_PACKET:
return 0;
default:
return WTAP_ERR_UNWRITABLE_ENCAP;
}
}
/* Write a record for a packet to a dump file.
* Returns TRUE on success, FALSE on failure. */
static gboolean eyesdn_dump(wtap_dumper *wdh,
const wtap_rec *rec,
const guint8 *pd, int *err, gchar **err_info _U_)
{
static const guint8 start_flag = 0xff;
const union wtap_pseudo_header *pseudo_header = &rec->rec_header.packet_header.pseudo_header;
guint8 buf[EYESDN_HDR_LENGTH];
int usecs;
time_t secs;
int channel;
int origin;
int protocol;
int size;
/* We can only write packet records. */
if (rec->rec_type != REC_TYPE_PACKET) {
*err = WTAP_ERR_UNWRITABLE_REC_TYPE;
return FALSE;
}
/* Don't write out anything bigger than we can read.
* (The length field in packet headers is 16 bits, which
* imposes a hard limit.) */
if (rec->rec_header.packet_header.caplen > 65535) {
*err = WTAP_ERR_PACKET_TOO_LARGE;
return FALSE;
}
usecs=rec->ts.nsecs/1000;
secs=rec->ts.secs;
size=rec->rec_header.packet_header.caplen;
origin = pseudo_header->isdn.uton;
channel = pseudo_header->isdn.channel;
switch(rec->rec_header.packet_header.pkt_encap) {
case WTAP_ENCAP_ISDN:
protocol=EYESDN_ENCAP_ISDN; /* set depending on decoder format and mode */
break;
case WTAP_ENCAP_LAYER1_EVENT:
protocol=EYESDN_ENCAP_MSG;
break;
case WTAP_ENCAP_DPNSS:
protocol=EYESDN_ENCAP_DPNSS;
break;
#if 0
case WTAP_ENCAP_DASS2:
protocol=EYESDN_ENCAP_DASS2;
break;
#endif
case WTAP_ENCAP_ATM_PDUS_UNTRUNCATED:
protocol=EYESDN_ENCAP_ATM;
channel=0x80;
break;
case WTAP_ENCAP_LAPB:
protocol=EYESDN_ENCAP_LAPB;
break;
case WTAP_ENCAP_MTP2_WITH_PHDR:
protocol=EYESDN_ENCAP_MTP2;
break;
case WTAP_ENCAP_BACNET_MS_TP_WITH_PHDR:
protocol=EYESDN_ENCAP_BACNET;
break;
case WTAP_ENCAP_V5_EF:
protocol=EYESDN_ENCAP_V5_EF;
break;
default:
*err=WTAP_ERR_UNWRITABLE_ENCAP;
return FALSE;
}
phton24(&buf[0], usecs);
buf[3] = (guint8)0;
buf[4] = (guint8)(0xff & (secs >> 24));
buf[5] = (guint8)(0xff & (secs >> 16));
buf[6] = (guint8)(0xff & (secs >> 8));
buf[7] = (guint8)(0xff & (secs >> 0));
buf[8] = (guint8) channel;
buf[9] = (guint8) (origin?1:0) + (protocol << 1);
phtons(&buf[10], size);
/* start flag */
if (!wtap_dump_file_write(wdh, &start_flag, sizeof start_flag, err))
return FALSE;
if (!esc_write(wdh, buf, 12, err))
return FALSE;
if (!esc_write(wdh, pd, size, err))
return FALSE;
return TRUE;
}
static const struct supported_block_type eyesdn_blocks_supported[] = {
/*
* We support packet blocks, with no comments or other options.
*/
{ WTAP_BLOCK_PACKET, MULTIPLE_BLOCKS_SUPPORTED, NO_OPTIONS_SUPPORTED }
};
static const struct file_type_subtype_info eyesdn_info = {
"EyeSDN USB S0/E1 ISDN trace format", "eyesdn", "trc", NULL,
FALSE, BLOCKS_SUPPORTED(eyesdn_blocks_supported),
eyesdn_dump_can_write_encap, eyesdn_dump_open, NULL
};
void register_eyesdn(void)
{
eyesdn_file_type_subtype = wtap_register_file_type_subtype(&eyesdn_info);
wiretap: more work on file type/subtypes. Provide a wiretap routine to get an array of all savable file type/subtypes, sorted with pcap and pcapng at the top, followed by the other types, sorted either by the name or the description. Use that routine to list options for the -F flag for various commands Rename wtap_get_savable_file_types_subtypes() to wtap_get_savable_file_types_subtypes_for_file(), to indicate that it provides an array of all file type/subtypes in which a given file can be saved. Have it sort all types, other than the default type/subtype and, if there is one, the "other" type (both of which are put at the top), by the name or the description. Don't allow wtap_register_file_type_subtypes() to override any existing registrations; have them always register a new type. In that routine, if there are any emply slots in the table, due to an entry being unregistered, use it rather than allocating a new slot. Don't allow unregistration of built-in types. Rename the "dump open table" to the "file type/subtype table", as it has entries for all types/subtypes, even if we can't write them. Initialize that table in a routine that pre-allocates the GArray before filling it with built-in types/subtypes, so it doesn't keep getting reallocated. Get rid of wtap_num_file_types_subtypes - it's just a copy of the size of the GArray. Don't have wtap_file_type_subtype_description() crash if handed an file type/subtype that isn't a valid array index - just return NULL, as we do with wtap_file_type_subtype_name(). In wtap_name_to_file_type_subtype(), don't use WTAP_FILE_TYPE_SUBTYPE_ names for the backwards-compatibility names - map those names to the current names, and then look them up. This reduces the number of uses of hardwired WTAP_FILE_TYPE_SUBTYPE_ values. Clean up the type of wtap_module_count - it has no need to be a gulong. Have built-in wiretap file handlers register names to be used for their file type/subtypes, rather than building the table in init.lua. Add a new Lua C function get_wtap_filetypes() to construct the wtap_filetypes table, based on the registered names, and use it in init.lua. Add a #define WSLUA_INTERNAL_FUNCTION to register functions intended only for internal use in init.lua, so they can be made available from Lua without being documented. Get rid of WTAP_NUM_FILE_TYPES_SUBTYPES - most code has no need to use it, as it can just request arrays of types, and the space of type/subtype codes can be sparse due to registration in any case, so code has to be careful using it. wtap_get_num_file_types_subtypes() is no longer used, so remove it. It returns the number of elements in the file type/subtype array, which is not necessarily the name of known file type/subtypes, as there may have been some deregistered types, and those types do *not* get removed from the array, they just get cleared so that they're available for future allocation (we don't want the indices of any registered types to changes if another type is deregistered, as those indicates are the type/subtype values, so we can't shrink the array). Clean up white space and remove some comments that shouldn't have been added.
2021-02-17 06:24:47 +00:00
/*
* Register name for backwards compatibility with the
* wtap_filetypes table in Lua.
*/
wtap_register_backwards_compatibility_lua_name("EYESDN",
eyesdn_file_type_subtype);
}
/*
* Editor modelines - https://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:
*/