static int
read_packet_header(wtap *wth, FILE_T fh, union wtap_pseudo_header *pseudo_header,
packet_entry_header *packet_header, int *err, gchar **err_info)
{
int offset;
guint i;
tlv_header tlvh;
int seek_increment;
tlv_wireless_info wireless_header;
offset = 0;
/* pull off the packet header */
if (!wtap_read_bytes_or_eof(fh, packet_header, sizeof *packet_header,
err, err_info)) {
if (*err != 0)
return -1;
return 0; /* EOF */
}
offset += (int)sizeof *packet_header;
PACKET_ENTRY_HEADER_FROM_LE_IN_PLACE(*packet_header);
/* check the packet's magic number */
if (packet_header->packet_magic != observer_packet_magic) {
/*
* Some files are zero-padded at the end. There is no warning of this
* in the previous packet header information, such as setting
* offset_to_next_packet to zero. So detect this situation by treating
* an all-zero header as a sentinel. Return EOF when it is encountered,
* rather than treat it as a bad record.
*/
for (i = 0; i < sizeof *packet_header; i++) {
if (((guint8*) packet_header)[i] != 0)
break;
}
if (i == sizeof *packet_header) {
*err = 0;
return 0; /* EOF */
}
*err = WTAP_ERR_BAD_FILE;
*err_info = g_strdup_printf("Observer: bad record: Invalid magic number 0x%08x",
packet_header->packet_magic);
return -1;
}
/* initialize the pseudo header */
switch (wth->file_encap) {
case WTAP_ENCAP_ETHERNET:
/* There is no FCS in the frame */
pseudo_header->eth.fcs_len = 0;
break;
case WTAP_ENCAP_IEEE_802_11_WITH_RADIO:
memset(&pseudo_header->ieee_802_11, 0, sizeof(pseudo_header->ieee_802_11));
pseudo_header->ieee_802_11.fcs_len = 0;
pseudo_header->ieee_802_11.decrypted = FALSE;
pseudo_header->ieee_802_11.datapad = FALSE;
pseudo_header->ieee_802_11.phy = PHDR_802_11_PHY_UNKNOWN;
/* Updated below */
break;
}
/* process extra information */
for (i = 0; i < packet_header->number_of_information_elements; i++) {
/* read the TLV header */
if (!wtap_read_bytes(fh, &tlvh, sizeof tlvh, err, err_info))
return -1;
offset += (int)sizeof tlvh;
TLV_HEADER_FROM_LE_IN_PLACE(tlvh);
if (tlvh.length < sizeof tlvh) {
*err = WTAP_ERR_BAD_FILE;
*err_info = g_strdup_printf("Observer: bad record (TLV length %u < %lu)",
tlvh.length, (unsigned long)sizeof tlvh);
return -1;
}
/* process (or skip over) the current TLV */
switch (tlvh.type) {
case INFORMATION_TYPE_WIRELESS:
if (!wtap_read_bytes(fh, &wireless_header, sizeof wireless_header,
err, err_info))
return -1;
/* set decryption status */
/* XXX - what other bits are there in conditions? */
pseudo_header->ieee_802_11.decrypted = (wireless_header.conditions & WIRELESS_WEP_SUCCESS) != 0;
pseudo_header->ieee_802_11.has_channel = TRUE;
pseudo_header->ieee_802_11.channel = wireless_header.frequency;
pseudo_header->ieee_802_11.has_data_rate = TRUE;
pseudo_header->ieee_802_11.data_rate = wireless_header.rate;
pseudo_header->ieee_802_11.has_signal_percent = TRUE;
pseudo_header->ieee_802_11.signal_percent = wireless_header.strengthPercent;
offset += (int)sizeof wireless_header;
break;
default:
/* skip the TLV data */
seek_increment = tlvh.length - (int)sizeof tlvh;
if (seek_increment > 0) {
if (file_seek(fh, seek_increment, SEEK_CUR, err) == -1)
return -1;
}
offset += seek_increment;
}
}
return offset;
}
static int
read_packet_header(FILE_T fh, union wtap_pseudo_header *pseudo_header,
packet_entry_header *packet_header, int *err, gchar **err_info)
{
int offset;
int bytes_read;
guint i;
tlv_header tlvh;
int seek_increment;
tlv_wireless_info wireless_header;
offset = 0;
/* pull off the packet header */
bytes_read = file_read(packet_header, sizeof *packet_header, fh);
if (bytes_read != sizeof *packet_header) {
*err = file_error(fh, err_info);
if (*err != 0)
return -1;
return 0; /* EOF */
}
offset += bytes_read;
PACKET_ENTRY_HEADER_FROM_LE_IN_PLACE(*packet_header);
/* check the packet's magic number */
if (packet_header->packet_magic != observer_packet_magic) {
/*
* Some files are zero-padded at the end. There is no warning of this
* in the previous packet header information, such as setting
* offset_to_next_packet to zero. So detect this situation by treating
* an all-zero header as a sentinel. Return EOF when it is encountered,
* rather than treat it as a bad record.
*/
for (i = 0; i < sizeof *packet_header; i++) {
if (((guint8*) packet_header)[i] != 0)
break;
}
if (i == sizeof *packet_header) {
*err = 0;
return 0; /* EOF */
}
*err = WTAP_ERR_BAD_FILE;
*err_info = g_strdup_printf("Observer: bad record: Invalid magic number 0x%08x",
packet_header->packet_magic);
return -1;
}
/* process extra information */
for (i = 0; i < packet_header->number_of_information_elements; i++) {
/* read the TLV header */
bytes_read = file_read(&tlvh, sizeof tlvh, fh);
if (bytes_read != sizeof tlvh) {
*err = file_error(fh, err_info);
if (*err == 0)
*err = WTAP_ERR_SHORT_READ;
return -1;
}
offset += bytes_read;
TLV_HEADER_FROM_LE_IN_PLACE(tlvh);
if (tlvh.length < sizeof tlvh) {
*err = WTAP_ERR_BAD_FILE;
*err_info = g_strdup_printf("Observer: bad record (TLV length %u < %lu)",
tlvh.length, (unsigned long)sizeof tlvh);
return -1;
}
/* process (or skip over) the current TLV */
switch (tlvh.type) {
case INFORMATION_TYPE_WIRELESS:
bytes_read = file_read(&wireless_header, sizeof wireless_header, fh);
if (bytes_read != sizeof wireless_header) {
*err = file_error(fh, err_info);
if(*err == 0)
*err = WTAP_ERR_SHORT_READ;
return -1;
}
/* update the pseudo header */
pseudo_header->ieee_802_11.fcs_len = 0;
/* set decryption status */
pseudo_header->ieee_802_11.decrypted = (wireless_header.conditions & WIRELESS_WEP_SUCCESS) != 0;
pseudo_header->ieee_802_11.channel = wireless_header.frequency;
pseudo_header->ieee_802_11.data_rate = wireless_header.rate;
pseudo_header->ieee_802_11.signal_level = wireless_header.strengthPercent;
offset += bytes_read;
break;
default:
/* skip the TLV data */
seek_increment = tlvh.length - (int)sizeof tlvh;
if (seek_increment > 0) {
if (file_seek(fh, seek_increment, SEEK_CUR, err) == -1)
return -1;
}
offset += seek_increment;
}
}
return offset;
}
wtap_open_return_val network_instruments_open(wtap *wth, int *err, gchar **err_info)
{
int offset;
capture_file_header file_header;
guint i;
tlv_header tlvh;
int seek_increment;
int header_offset;
packet_entry_header packet_header;
observer_dump_private_state * private_state = NULL;
offset = 0;
/* read in the buffer file header */
if (!wtap_read_bytes(wth->fh, &file_header, sizeof file_header,
err, err_info)) {
if (*err != WTAP_ERR_SHORT_READ)
return WTAP_OPEN_ERROR;
return WTAP_OPEN_NOT_MINE;
}
offset += (int)sizeof file_header;
CAPTURE_FILE_HEADER_FROM_LE_IN_PLACE(file_header);
/* check if version info is present */
if (memcmp(file_header.observer_version, network_instruments_magic, true_magic_length)!=0) {
return WTAP_OPEN_NOT_MINE;
}
/* initialize the private state */
private_state = (observer_dump_private_state *) g_malloc(sizeof(observer_dump_private_state));
private_state->time_format = TIME_INFO_LOCAL;
wth->priv = (void *) private_state;
/* get the location of the first packet */
/* v15 and newer uses high byte offset, in previous versions it will be 0 */
header_offset = file_header.offset_to_first_packet + ((int)(file_header.offset_to_first_packet_high_byte)<<16);
/* process extra information */
for (i = 0; i < file_header.number_of_information_elements; i++) {
/* for safety break if we've reached the first packet */
if (offset >= header_offset)
break;
/* read the TLV header */
if (!wtap_read_bytes(wth->fh, &tlvh, sizeof tlvh, err, err_info))
return WTAP_OPEN_ERROR;
offset += (int)sizeof tlvh;
TLV_HEADER_FROM_LE_IN_PLACE(tlvh);
if (tlvh.length < sizeof tlvh) {
*err = WTAP_ERR_BAD_FILE;
*err_info = g_strdup_printf("Observer: bad record (TLV length %u < %lu)",
tlvh.length, (unsigned long)sizeof tlvh);
return WTAP_OPEN_ERROR;
}
/* process (or skip over) the current TLV */
switch (tlvh.type) {
case INFORMATION_TYPE_TIME_INFO:
if (!wtap_read_bytes(wth->fh, &private_state->time_format,
sizeof private_state->time_format,
err, err_info))
return WTAP_OPEN_ERROR;
private_state->time_format = GUINT32_FROM_LE(private_state->time_format);
offset += (int)sizeof private_state->time_format;
break;
default:
seek_increment = tlvh.length - (int)sizeof tlvh;
if (seek_increment > 0) {
if (file_seek(wth->fh, seek_increment, SEEK_CUR, err) == -1)
return WTAP_OPEN_ERROR;
}
offset += seek_increment;
}
}
/* get to the first packet */
if (header_offset < offset) {
*err = WTAP_ERR_BAD_FILE;
*err_info = g_strdup_printf("Observer: bad record (offset to first packet %d < %d)",
header_offset, offset);
return WTAP_OPEN_ERROR;
}
seek_increment = header_offset - offset;
if (seek_increment > 0) {
if (file_seek(wth->fh, seek_increment, SEEK_CUR, err) == -1)
return WTAP_OPEN_ERROR;
}
/* pull off the packet header */
if (!wtap_read_bytes(wth->fh, &packet_header, sizeof packet_header,
err, err_info))
return WTAP_OPEN_ERROR;
PACKET_ENTRY_HEADER_FROM_LE_IN_PLACE(packet_header);
/* check the packet's magic number */
if (packet_header.packet_magic != observer_packet_magic) {
*err = WTAP_ERR_UNSUPPORTED;
*err_info = g_strdup_printf("Observer: unsupported packet version %ul", packet_header.packet_magic);
return WTAP_OPEN_ERROR;
}
/* check the data link type */
if (observer_to_wtap_encap(packet_header.network_type) == WTAP_ENCAP_UNKNOWN) {
*err = WTAP_ERR_UNSUPPORTED;
*err_info = g_strdup_printf("Observer: network type %u unknown or unsupported", packet_header.network_type);
return WTAP_OPEN_ERROR;
}
wth->file_encap = observer_to_wtap_encap(packet_header.network_type);
/* set up the rest of the capture parameters */
private_state->packet_count = 0;
private_state->network_type = wtap_to_observer_encap(wth->file_encap);
wth->subtype_read = observer_read;
wth->subtype_seek_read = observer_seek_read;
wth->subtype_close = NULL;
wth->subtype_sequential_close = NULL;
wth->snapshot_length = 0; /* not available in header */
wth->file_tsprec = WTAP_TSPREC_NSEC;
wth->file_type_subtype = WTAP_FILE_TYPE_SUBTYPE_NETWORK_INSTRUMENTS;
/* reset the pointer to the first packet */
if (file_seek(wth->fh, header_offset, SEEK_SET, err) == -1)
return WTAP_OPEN_ERROR;
init_gmt_to_localtime_offset();
return WTAP_OPEN_MINE;
}
wtap_open_return_val network_instruments_open(wtap *wth, int *err, gchar **err_info)
{
guint offset;
capture_file_header file_header;
guint header_offset;
guint i;
tlv_header tlvh;
guint seek_increment;
packet_entry_header packet_header;
observer_dump_private_state * private_state = NULL;
offset = 0;
/* read in the buffer file header */
if (!wtap_read_bytes(wth->fh, &file_header, sizeof file_header,
err, err_info)) {
if (*err != WTAP_ERR_SHORT_READ)
return WTAP_OPEN_ERROR;
return WTAP_OPEN_NOT_MINE;
}
offset += (guint)sizeof file_header;
CAPTURE_FILE_HEADER_FROM_LE_IN_PLACE(file_header);
/* check if version info is present */
if (memcmp(file_header.observer_version, network_instruments_magic, true_magic_length)!=0) {
return WTAP_OPEN_NOT_MINE;
}
/* get the location of the first packet */
/* v15 and newer uses high byte offset, in previous versions it will be 0 */
header_offset = file_header.offset_to_first_packet + ((guint)(file_header.offset_to_first_packet_high_byte)<<16);
if (offset > header_offset) {
/*
* The packet data begins before the file header ends.
*/
*err = WTAP_ERR_BAD_FILE;
*err_info = g_strdup_printf("Observer: The first packet begins in the middle of the file header");
return WTAP_OPEN_ERROR;
}
/* initialize the private state */
private_state = (observer_dump_private_state *) g_malloc(sizeof(observer_dump_private_state));
private_state->time_format = TIME_INFO_LOCAL;
wth->priv = (void *) private_state;
/* process extra information */
for (i = 0; i < file_header.number_of_information_elements; i++) {
guint tlv_data_length;
/*
* Make sure reading the TLV header won't put us in the middle
* of the packet data.
*/
if (offset + (guint)sizeof tlvh > header_offset) {
/*
* We're at or past the point where the packet data begins,
* but we have the IE header to read.
*/
*err = WTAP_ERR_BAD_FILE;
*err_info = g_strdup_printf("Observer: TLVs run into the first packet data");
return WTAP_OPEN_ERROR;
}
/* read the TLV header */
if (!wtap_read_bytes(wth->fh, &tlvh, sizeof tlvh, err, err_info))
return WTAP_OPEN_ERROR;
offset += (guint)sizeof tlvh;
TLV_HEADER_FROM_LE_IN_PLACE(tlvh);
if (tlvh.length < sizeof tlvh) {
*err = WTAP_ERR_BAD_FILE;
*err_info = g_strdup_printf("Observer: bad record (TLV length %u < %lu)",
tlvh.length, (unsigned long)sizeof tlvh);
return WTAP_OPEN_ERROR;
}
tlv_data_length = tlvh.length - (guint)sizeof tlvh;
/*
* Make sure reading the TLV data won't put us in the middle
* of the packet data.
*/
if (offset + tlv_data_length > header_offset) {
/*
* We're at or past the point where the packet data begins,
* but we have the IE data to read.
*/
*err = WTAP_ERR_BAD_FILE;
*err_info = g_strdup_printf("Observer: TLVs run into the first packet data");
return WTAP_OPEN_ERROR;
}
/* process (or skip over) the current TLV */
switch (tlvh.type) {
case INFORMATION_TYPE_TIME_INFO:
if (tlvh.length != sizeof tlvh + sizeof private_state->time_format) {
*err = WTAP_ERR_BAD_FILE;
*err_info = g_strdup_printf("Observer: bad record (time information TLV length %u != %lu)",
tlvh.length,
(unsigned long)(sizeof tlvh + sizeof private_state->time_format));
return WTAP_OPEN_ERROR;
}
if (!wtap_read_bytes(wth->fh, &private_state->time_format,
sizeof private_state->time_format,
err, err_info))
return WTAP_OPEN_ERROR;
private_state->time_format = GUINT32_FROM_LE(private_state->time_format);
offset += (guint)sizeof private_state->time_format;
break;
default:
tlv_data_length = tlvh.length - (guint)sizeof tlvh;
if (tlv_data_length > 0) {
if (!wtap_read_bytes(wth->fh, NULL, tlv_data_length, err, err_info))
return WTAP_OPEN_ERROR;
}
offset += tlv_data_length;
}
}
/* get to the first packet */
seek_increment = header_offset - offset;
if (seek_increment != 0) {
if (!wtap_read_bytes(wth->fh, NULL, seek_increment, err, err_info))
return WTAP_OPEN_ERROR;
}
/*
* We assume that all packets in a file have the same network type,
* whether they're data or expert information packets, and thus
* we can attempt to determine the network type by reading the
* first packet.
*
* If that's *not* the case, we need to use WTAP_ENCAP_PER_PACKET.
*
* Read the packet header. Don't assume there *is* a packet;
* if there isn't, report that as a bad file. (If we use
* WTAP_ENCAP_PER_PACKET, we don't need to handle that case, as
* we don't need to read the first packet.
*/
if (!wtap_read_bytes_or_eof(wth->fh, &packet_header, sizeof packet_header,
err, err_info)) {
if (*err == 0) {
/*
* EOF, so there *are* no records.
*/
*err = WTAP_ERR_BAD_FILE;
*err_info = g_strdup_printf("Observer: No records in the file, so we can't determine the link-layer type");
}
return WTAP_OPEN_ERROR;
}
PACKET_ENTRY_HEADER_FROM_LE_IN_PLACE(packet_header);
/* check the packet's magic number */
if (packet_header.packet_magic != observer_packet_magic) {
*err = WTAP_ERR_UNSUPPORTED;
*err_info = g_strdup_printf("Observer: unsupported packet version %ul", packet_header.packet_magic);
return WTAP_OPEN_ERROR;
}
/* check the data link type */
if (observer_to_wtap_encap(packet_header.network_type) == WTAP_ENCAP_UNKNOWN) {
*err = WTAP_ERR_UNSUPPORTED;
*err_info = g_strdup_printf("Observer: network type %u unknown or unsupported", packet_header.network_type);
return WTAP_OPEN_ERROR;
}
wth->file_encap = observer_to_wtap_encap(packet_header.network_type);
/* set up the rest of the capture parameters */
private_state->packet_count = 0;
private_state->network_type = wtap_to_observer_encap(wth->file_encap);
wth->subtype_read = observer_read;
wth->subtype_seek_read = observer_seek_read;
wth->subtype_close = NULL;
wth->subtype_sequential_close = NULL;
wth->snapshot_length = 0; /* not available in header */
wth->file_tsprec = WTAP_TSPREC_NSEC;
wth->file_type_subtype = WTAP_FILE_TYPE_SUBTYPE_NETWORK_INSTRUMENTS;
/* reset the pointer to the first packet */
if (file_seek(wth->fh, header_offset, SEEK_SET, err) == -1)
return WTAP_OPEN_ERROR;
if (init_gmt_to_localtime_offset() != NULL) {
*err = WTAP_ERR_INTERNAL;
/*
* XXX - we should return the error string, so the caller
* can report the details of the internal error, but that
* would require plugin file readers to do so for internal
* errors as well, which could break binary compatibility;
* we'll do that in the next release.
*/
return WTAP_OPEN_ERROR;
}
return WTAP_OPEN_MINE;
}
