tcpdump/print-ppi.c
2020-09-28 17:04:08 +02:00

132 lines
3.0 KiB
C

/*
* Oracle
*/
/* \summary: Per-Packet Information (DLT_PPI) printer */
/* Specification:
* Per-Packet Information Header Specification - Version 1.0.7
* https://web.archive.org/web/20160328114748/http://www.cacetech.com/documents/PPI%20Header%20format%201.0.7.pdf
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include "netdissect-stdinc.h"
#include "netdissect.h"
#include "extract.h"
typedef struct ppi_header {
nd_uint8_t ppi_ver; /* Version. Currently 0 */
nd_uint8_t ppi_flags; /* Flags. */
nd_uint16_t ppi_len; /* Length of entire message, including
* this header and TLV payload. */
nd_uint32_t ppi_dlt; /* Data Link Type of the captured
* packet data. */
} ppi_header_t;
#define PPI_HDRLEN 8
#ifdef DLT_PPI
static void
ppi_header_print(netdissect_options *ndo, const u_char *bp, u_int length)
{
const ppi_header_t *hdr;
uint16_t len;
uint32_t dlt;
const char *dltname;
hdr = (const ppi_header_t *)bp;
len = GET_LE_U_2(hdr->ppi_len);
dlt = GET_LE_U_4(hdr->ppi_dlt);
dltname = pcap_datalink_val_to_name(dlt);
if (!ndo->ndo_qflag) {
ND_PRINT("V.%u DLT %s (%u) len %u", GET_U_1(hdr->ppi_ver),
(dltname != NULL ? dltname : "UNKNOWN"), dlt,
len);
} else {
ND_PRINT("%s", (dltname != NULL ? dltname : "UNKNOWN"));
}
ND_PRINT(", length %u: ", length);
}
/*
* This is the top level routine of the printer. 'p' points
* to the ether header of the packet, 'h->ts' is the timestamp,
* 'h->len' is the length of the packet off the wire, and 'h->caplen'
* is the number of bytes actually captured.
*/
void
ppi_if_print(netdissect_options *ndo,
const struct pcap_pkthdr *h, const u_char *p)
{
if_printer printer;
const ppi_header_t *hdr;
u_int caplen = h->caplen;
u_int length = h->len;
uint16_t len;
uint32_t dlt;
uint32_t hdrlen;
struct pcap_pkthdr nhdr;
ndo->ndo_protocol = "ppi";
if (caplen < sizeof(ppi_header_t)) {
nd_print_trunc(ndo);
ndo->ndo_ll_hdr_len += caplen;
return;
}
hdr = (const ppi_header_t *)p;
len = GET_LE_U_2(hdr->ppi_len);
if (len < sizeof(ppi_header_t) || len > 65532) {
/* It MUST be between 8 and 65,532 inclusive (spec 3.1.3) */
ND_PRINT(" [length %u < %zu or > 65532]", len,
sizeof(ppi_header_t));
nd_print_invalid(ndo);
ndo->ndo_ll_hdr_len += caplen;
return;
}
if (caplen < len) {
/*
* If we don't have the entire PPI header, don't
* bother.
*/
nd_print_trunc(ndo);
ndo->ndo_ll_hdr_len += caplen;
return;
}
dlt = GET_LE_U_4(hdr->ppi_dlt);
if (ndo->ndo_eflag)
ppi_header_print(ndo, p, length);
length -= len;
caplen -= len;
p += len;
printer = lookup_printer(dlt);
if (printer != NULL) {
nhdr = *h;
nhdr.caplen = caplen;
nhdr.len = length;
printer(ndo, &nhdr, p);
hdrlen = ndo->ndo_ll_hdr_len;
} else {
if (!ndo->ndo_eflag)
ppi_header_print(ndo, (const u_char *)hdr, length + len);
if (!ndo->ndo_suppress_default_print)
ND_DEFAULTPRINT(p, caplen);
hdrlen = 0;
}
ndo->ndo_ll_hdr_len += len + hdrlen;
}
#endif /* DLT_PPI */