/*
* The DLT_USB_LINUX and DLT_USB_LINUX_MMAPPED headers are in host
* byte order when capturing (it's supplied directly from a
* memory-mapped buffer shared by the kernel).
*
* When reading a DLT_USB_LINUX or DLT_USB_LINUX_MMAPPED capture file,
* we need to convert it from the byte order of the host that wrote
* the file to this host's byte order.
*/
static void
swap_linux_usb_header(const struct pcap_pkthdr *hdr, u_char *buf,
int header_len_64_bytes)
{
pcap_usb_header_mmapped *uhdr = (pcap_usb_header_mmapped *)buf;
bpf_u_int32 offset = 0;
usb_isodesc *pisodesc;
int32_t numdesc, i;
/*
* "offset" is the offset *past* the field we're swapping;
* we skip the field *before* checking to make sure
* the captured data length includes the entire field.
*/
/*
* The URB id is a totally opaque value; do we really need to
* convert it to the reading host's byte order???
*/
offset += 8; /* skip past id */
if (hdr->caplen < offset)
return;
uhdr->id = SWAPLL(uhdr->id);
offset += 4; /* skip past various 1-byte fields */
offset += 2; /* skip past bus_id */
if (hdr->caplen < offset)
return;
uhdr->bus_id = SWAPSHORT(uhdr->bus_id);
offset += 2; /* skip past various 1-byte fields */
offset += 8; /* skip past ts_sec */
if (hdr->caplen < offset)
return;
uhdr->ts_sec = SWAPLL(uhdr->ts_sec);
offset += 4; /* skip past ts_usec */
if (hdr->caplen < offset)
return;
uhdr->ts_usec = SWAPLONG(uhdr->ts_usec);
offset += 4; /* skip past status */
if (hdr->caplen < offset)
return;
uhdr->status = SWAPLONG(uhdr->status);
offset += 4; /* skip past urb_len */
if (hdr->caplen < offset)
return;
uhdr->urb_len = SWAPLONG(uhdr->urb_len);
offset += 4; /* skip past data_len */
if (hdr->caplen < offset)
return;
uhdr->data_len = SWAPLONG(uhdr->data_len);
if (uhdr->transfer_type == URB_ISOCHRONOUS) {
offset += 4; /* skip past s.iso.error_count */
if (hdr->caplen < offset)
return;
uhdr->s.iso.error_count = SWAPLONG(uhdr->s.iso.error_count);
offset += 4; /* skip past s.iso.numdesc */
if (hdr->caplen < offset)
return;
uhdr->s.iso.numdesc = SWAPLONG(uhdr->s.iso.numdesc);
} else
offset += 8; /* skip USB setup header */
if (header_len_64_bytes) {
/*
* This is either the "version 1" header, with
* 16 bytes of additional fields at the end, or
* a "version 0" header from a memory-mapped
* capture, with 16 bytes of zeroed-out padding
* at the end. Byte swap them as if this were
* a "version 1" header.
*/
offset += 4; /* skip past interval */
if (hdr->caplen < offset)
return;
uhdr->interval = SWAPLONG(uhdr->interval);
offset += 4; /* skip past start_frame */
if (hdr->caplen < offset)
return;
uhdr->start_frame = SWAPLONG(uhdr->start_frame);
offset += 4; /* skip past xfer_flags */
if (hdr->caplen < offset)
return;
uhdr->xfer_flags = SWAPLONG(uhdr->xfer_flags);
offset += 4; /* skip past ndesc */
if (hdr->caplen < offset)
return;
uhdr->ndesc = SWAPLONG(uhdr->ndesc);
}
if (uhdr->transfer_type == URB_ISOCHRONOUS) {
/* swap the values in struct linux_usb_isodesc */
pisodesc = (usb_isodesc *)(void *)(buf+offset);
numdesc = uhdr->s.iso.numdesc;
for (i = 0; i < numdesc; i++) {
offset += 4; /* skip past status */
if (hdr->caplen < offset)
return;
pisodesc->status = SWAPLONG(pisodesc->status);
offset += 4; /* skip past offset */
if (hdr->caplen < offset)
return;
pisodesc->offset = SWAPLONG(pisodesc->offset);
offset += 4; /* skip past len */
if (hdr->caplen < offset)
return;
pisodesc->len = SWAPLONG(pisodesc->len);
offset += 4; /* skip past padding */
pisodesc++;
}
}
}
static int
process_idb_options(pcap_t *p, struct pcapng_interface_description_fields *idbp,
struct block_cursor *cursor, u_int *tsresol,
u_int64_t *tsoffset, char *errbuf)
{
struct pcapng_option_header opthdr;
void *optvalue;
int saw_tsresol, saw_tsoffset, saw_ifname;
u_char tsresol_opt;
u_int i;
saw_tsresol = 0;
saw_tsoffset = 0;
saw_ifname = 0;
while (cursor->data_remaining != 0) {
/*
* Get the option header.
*/
if (get_opthdr_from_block_data(&opthdr, p->sf.swapped, cursor, errbuf) == NULL) {
/*
* Option header is cut short.
*/
goto fail; /* error */
}
/*
* Get option value.
*/
optvalue = get_optvalue_from_block_data(cursor, &opthdr,
errbuf);
if (optvalue == NULL) {
/*
* Option value is cut short.
*/
goto fail; /* error */
}
switch (opthdr.option_code) {
case PCAPNG_IF_NAME:
if (saw_ifname) {
snprintf(errbuf, PCAP_ERRBUF_SIZE,
"Interface Description Block has more than one if_name option");
goto fail; /* error */
}
saw_ifname = 1;
break;
case PCAPNG_OPT_ENDOFOPT:
if (opthdr.option_length != 0) {
snprintf(errbuf, PCAP_ERRBUF_SIZE,
"Interface Description Block has opt_endofopt option with length %u != 0",
opthdr.option_length);
goto fail; /* error */
}
goto done;
case PCAPNG_IF_TSRESOL:
if (opthdr.option_length != 1) {
snprintf(errbuf, PCAP_ERRBUF_SIZE,
"Interface Description Block has if_tsresol option with length %u != 1",
opthdr.option_length);
goto fail; /* error */
}
if (saw_tsresol) {
snprintf(errbuf, PCAP_ERRBUF_SIZE,
"Interface Description Block has more than one if_tsresol option");
goto fail; /* error */
}
saw_tsresol = 1;
tsresol_opt = *(u_int *)optvalue;
if (tsresol_opt & 0x80) {
/*
* Resolution is negative power of 2.
*/
*tsresol = 1 << (tsresol_opt & 0x7F);
} else {
/*
* Resolution is negative power of 10.
*/
*tsresol = 1;
for (i = 0; i < tsresol_opt; i++)
*tsresol *= 10;
}
if (*tsresol == 0) {
/*
* Resolution is too high.
*/
if (tsresol_opt & 0x80) {
snprintf(errbuf, PCAP_ERRBUF_SIZE,
"Interface Description Block if_tsresol option resolution 2^-%u is too high",
tsresol_opt & 0x7F);
} else {
snprintf(errbuf, PCAP_ERRBUF_SIZE,
"Interface Description Block if_tsresol option resolution 10^-%u is too high",
tsresol_opt);
}
goto fail; /* error */
}
break;
case PCAPNG_IF_TSOFFSET:
if (opthdr.option_length != 8) {
snprintf(errbuf, PCAP_ERRBUF_SIZE,
"Interface Description Block has if_tsoffset option with length %u != 8",
opthdr.option_length);
goto fail; /* error */
}
if (saw_tsoffset) {
snprintf(errbuf, PCAP_ERRBUF_SIZE,
"Interface Description Block has more than one if_tsoffset option");
goto fail; /* error */
}
saw_tsoffset = 1;
memcpy(tsoffset, optvalue, sizeof(*tsoffset));
if (p->sf.swapped)
*tsoffset = SWAPLL(*tsoffset);
break;
default:
break;
}
}
done:
/*
* Count this interface.
*/
p->ifcount++;
/*
* Compute the scaling factor to convert the
* sub-second part of the time stamp to
* microseconds.
*/
if (p->sf.tsresol > 1000000) {
/*
* Higher than microsecond resolution;
* scale down to microseconds.
*/
p->sf.tsscale = (p->sf.tsresol / 1000000);
} else {
/*
* Lower than microsecond resolution;
* scale up to microseconds.
*/
p->sf.tsscale = (1000000 / p->sf.tsresol);
}
return (0);
fail:
return (-1);
}
static int
process_idb_options(pcap_t *p, struct block_cursor *cursor, u_int *tsresol,
u_int64_t *tsoffset, char *errbuf)
{
struct option_header *opthdr;
void *optvalue;
int saw_tsresol, saw_tsoffset;
u_char tsresol_opt;
u_int i;
saw_tsresol = 0;
saw_tsoffset = 0;
while (cursor->data_remaining != 0) {
/*
* Get the option header.
*/
opthdr = get_opthdr_from_block_data(p, cursor, errbuf);
if (opthdr == NULL) {
/*
* Option header is cut short.
*/
return (-1);
}
/*
* Get option value.
*/
optvalue = get_optvalue_from_block_data(cursor, opthdr,
errbuf);
if (optvalue == NULL) {
/*
* Option value is cut short.
*/
return (-1);
}
switch (opthdr->option_code) {
case OPT_ENDOFOPT:
if (opthdr->option_length != 0) {
snprintf(errbuf, PCAP_ERRBUF_SIZE,
"Interface Description Block has opt_endofopt option with length %u != 0",
opthdr->option_length);
return (-1);
}
goto done;
case IF_TSRESOL:
if (opthdr->option_length != 1) {
snprintf(errbuf, PCAP_ERRBUF_SIZE,
"Interface Description Block has if_tsresol option with length %u != 1",
opthdr->option_length);
return (-1);
}
if (saw_tsresol) {
snprintf(errbuf, PCAP_ERRBUF_SIZE,
"Interface Description Block has more than one if_tsresol option");
return (-1);
}
saw_tsresol = 1;
memcpy(&tsresol_opt, optvalue, sizeof(tsresol_opt));
if (tsresol_opt & 0x80) {
/*
* Resolution is negative power of 2.
*/
*tsresol = 1 << (tsresol_opt & 0x7F);
} else {
/*
* Resolution is negative power of 10.
*/
*tsresol = 1;
for (i = 0; i < tsresol_opt; i++)
*tsresol *= 10;
}
if (*tsresol == 0) {
/*
* Resolution is too high.
*/
if (tsresol_opt & 0x80) {
snprintf(errbuf, PCAP_ERRBUF_SIZE,
"Interface Description Block if_tsresol option resolution 2^-%u is too high",
tsresol_opt & 0x7F);
} else {
snprintf(errbuf, PCAP_ERRBUF_SIZE,
"Interface Description Block if_tsresol option resolution 10^-%u is too high",
tsresol_opt);
}
return (-1);
}
break;
case IF_TSOFFSET:
if (opthdr->option_length != 8) {
snprintf(errbuf, PCAP_ERRBUF_SIZE,
"Interface Description Block has if_tsoffset option with length %u != 8",
opthdr->option_length);
return (-1);
}
if (saw_tsoffset) {
snprintf(errbuf, PCAP_ERRBUF_SIZE,
"Interface Description Block has more than one if_tsoffset option");
return (-1);
}
saw_tsoffset = 1;
memcpy(tsoffset, optvalue, sizeof(*tsoffset));
if (p->swapped)
*tsoffset = (uint64_t)SWAPLL(*tsoffset);
break;
default:
break;
}
}
done:
return (0);
}
static int
process_idb_options(pcap_t *p, struct block_cursor *cursor, uint64_t *tsresol,
uint64_t *tsoffset, int *is_binary, char *errbuf)
{
struct option_header *opthdr;
void *optvalue;
int saw_tsresol, saw_tsoffset;
uint8_t tsresol_opt;
u_int i;
saw_tsresol = 0;
saw_tsoffset = 0;
while (cursor->data_remaining != 0) {
/*
* Get the option header.
*/
opthdr = get_opthdr_from_block_data(p, cursor, errbuf);
if (opthdr == NULL) {
/*
* Option header is cut short.
*/
return (-1);
}
/*
* Get option value.
*/
optvalue = get_optvalue_from_block_data(cursor, opthdr,
errbuf);
if (optvalue == NULL) {
/*
* Option value is cut short.
*/
return (-1);
}
switch (opthdr->option_code) {
case OPT_ENDOFOPT:
if (opthdr->option_length != 0) {
pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
"Interface Description Block has opt_endofopt option with length %u != 0",
opthdr->option_length);
return (-1);
}
goto done;
case IF_TSRESOL:
if (opthdr->option_length != 1) {
pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
"Interface Description Block has if_tsresol option with length %u != 1",
opthdr->option_length);
return (-1);
}
if (saw_tsresol) {
pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
"Interface Description Block has more than one if_tsresol option");
return (-1);
}
saw_tsresol = 1;
memcpy(&tsresol_opt, optvalue, sizeof(tsresol_opt));
if (tsresol_opt & 0x80) {
/*
* Resolution is negative power of 2.
*/
uint8_t tsresol_shift = (tsresol_opt & 0x7F);
if (tsresol_shift > 63) {
/*
* Resolution is too high; 2^-{res}
* won't fit in a 64-bit value.
*/
pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
"Interface Description Block if_tsresol option resolution 2^-%u is too high",
tsresol_shift);
return (-1);
}
*is_binary = 1;
*tsresol = ((uint64_t)1) << tsresol_shift;
} else {
/*
* Resolution is negative power of 10.
*/
if (tsresol_opt > 19) {
/*
* Resolution is too high; 2^-{res}
* won't fit in a 64-bit value (the
* largest power of 10 that fits
* in a 64-bit value is 10^19, as
* the largest 64-bit unsigned
* value is ~1.8*10^19).
*/
pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
"Interface Description Block if_tsresol option resolution 10^-%u is too high",
tsresol_opt);
return (-1);
}
*is_binary = 0;
*tsresol = 1;
for (i = 0; i < tsresol_opt; i++)
*tsresol *= 10;
}
break;
case IF_TSOFFSET:
if (opthdr->option_length != 8) {
pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
"Interface Description Block has if_tsoffset option with length %u != 8",
opthdr->option_length);
return (-1);
}
if (saw_tsoffset) {
pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
"Interface Description Block has more than one if_tsoffset option");
return (-1);
}
saw_tsoffset = 1;
memcpy(tsoffset, optvalue, sizeof(*tsoffset));
if (p->swapped)
*tsoffset = SWAPLL(*tsoffset);
break;
default:
break;
}
}
done:
return (0);
}
