/* \summary: DLT_NFLOG printer */
-#ifdef HAVE_CONFIG_H
#include <config.h>
-#endif
#include "netdissect-stdinc.h"
+#define ND_LONGJMP_FROM_TCHECK
#include "netdissect.h"
-static const char tstr[] = " [|nflog]";
+#include "extract.h"
-#if defined(DLT_NFLOG) && defined(HAVE_PCAP_NFLOG_H)
-#include <pcap/nflog.h>
+#ifdef DLT_NFLOG
+/*
+ * Structure of an NFLOG header and TLV parts, as described at
+ * https://www.tcpdump.org/linktypes/LINKTYPE_NFLOG.html
+ *
+ * The NFLOG header is big-endian.
+ *
+ * The TLV length and type are in host byte order. The value is either
+ * big-endian or is an array of bytes in some externally-specified byte
+ * order (text string, link-layer address, link-layer header, packet
+ * data, etc.).
+ */
+typedef struct nflog_hdr {
+ nd_uint8_t nflog_family; /* address family */
+ nd_uint8_t nflog_version; /* version */
+ nd_uint16_t nflog_rid; /* resource ID */
+} nflog_hdr_t;
+
+#define NFLOG_HDR_LEN sizeof(nflog_hdr_t)
+
+typedef struct nflog_tlv {
+ nd_uint16_t tlv_length; /* tlv length */
+ nd_uint16_t tlv_type; /* tlv type */
+ /* value follows this */
+} nflog_tlv_t;
+
+#define NFLOG_TLV_LEN sizeof(nflog_tlv_t)
+
+typedef struct nflog_packet_hdr {
+ nd_uint16_t hw_protocol; /* hw protocol */
+ nd_uint8_t hook; /* netfilter hook */
+ nd_byte pad[1]; /* padding to 32 bits */
+} nflog_packet_hdr_t;
+
+typedef struct nflog_hwaddr {
+ nd_uint16_t hw_addrlen; /* address length */
+ nd_byte pad[2]; /* padding to 32-bit boundary */
+ nd_byte hw_addr[8]; /* address, up to 8 bytes */
+} nflog_hwaddr_t;
+
+typedef struct nflog_timestamp {
+ nd_uint64_t sec;
+ nd_uint64_t usec;
+} nflog_timestamp_t;
+
+/*
+ * TLV types.
+ */
+#define NFULA_PACKET_HDR 1 /* nflog_packet_hdr_t */
+#define NFULA_MARK 2 /* packet mark from skbuff */
+#define NFULA_TIMESTAMP 3 /* nflog_timestamp_t for skbuff's time stamp */
+#define NFULA_IFINDEX_INDEV 4 /* ifindex of device on which packet received (possibly bridge group) */
+#define NFULA_IFINDEX_OUTDEV 5 /* ifindex of device on which packet transmitted (possibly bridge group) */
+#define NFULA_IFINDEX_PHYSINDEV 6 /* ifindex of physical device on which packet received (not bridge group) */
+#define NFULA_IFINDEX_PHYSOUTDEV 7 /* ifindex of physical device on which packet transmitted (not bridge group) */
+#define NFULA_HWADDR 8 /* nflog_hwaddr_t for hardware address */
+#define NFULA_PAYLOAD 9 /* packet payload */
+#define NFULA_PREFIX 10 /* text string - null-terminated, count includes NUL */
+#define NFULA_UID 11 /* UID owning socket on which packet was sent/received */
+#define NFULA_SEQ 12 /* sequence number of packets on this NFLOG socket */
+#define NFULA_SEQ_GLOBAL 13 /* sequence number of packets on all NFLOG sockets */
+#define NFULA_GID 14 /* GID owning socket on which packet was sent/received */
+#define NFULA_HWTYPE 15 /* ARPHRD_ type of skbuff's device */
+#define NFULA_HWHEADER 16 /* skbuff's MAC-layer header */
+#define NFULA_HWLEN 17 /* length of skbuff's MAC-layer header */
+
+/*
+ * Define two constants specifically for the two AF code points from the
+ * LINKTYPE_NFLOG specification above and use these constants instead of
+ * AF_INET and AF_INET6. This is the only way to dissect the "wire" encoding
+ * correctly because some BSD systems define AF_INET6 differently from Linux
+ * (see af.h) and Haiku defines both AF_INET and AF_INET6 differently from
+ * Linux.
+ */
+#define NFLOG_AF_INET 2
+#define NFLOG_AF_INET6 10
static const struct tok nflog_values[] = {
- { AF_INET, "IPv4" },
-#ifdef AF_INET6
- { AF_INET6, "IPv6" },
-#endif /*AF_INET6*/
+ { NFLOG_AF_INET, "IPv4" },
+ { NFLOG_AF_INET6, "IPv6" },
{ 0, NULL }
};
static void
nflog_hdr_print(netdissect_options *ndo, const nflog_hdr_t *hdr, u_int length)
{
- ND_PRINT("version %d, resource ID %d", hdr->nflog_version, ntohs(hdr->nflog_rid));
+ ND_PRINT("version %u, resource ID %u",
+ GET_U_1(hdr->nflog_version), GET_BE_U_2(hdr->nflog_rid));
if (!ndo->ndo_qflag) {
- ND_PRINT(", family %s (%d)",
+ ND_PRINT(", family %s (%u)",
tok2str(nflog_values, "Unknown",
- hdr->nflog_family),
- hdr->nflog_family);
+ GET_U_1(hdr->nflog_family)),
+ GET_U_1(hdr->nflog_family));
} else {
ND_PRINT(", %s",
tok2str(nflog_values,
"Unknown NFLOG (0x%02x)",
- hdr->nflog_family));
+ GET_U_1(hdr->nflog_family)));
}
ND_PRINT(", length %u: ", length);
}
-u_int
+void
nflog_if_print(netdissect_options *ndo,
- const struct pcap_pkthdr *h, const u_char *p)
+ const struct pcap_pkthdr *h, const u_char *p)
{
const nflog_hdr_t *hdr = (const nflog_hdr_t *)p;
uint16_t size;
- uint16_t h_size = sizeof(nflog_hdr_t);
+ uint16_t h_size = NFLOG_HDR_LEN;
u_int caplen = h->caplen;
u_int length = h->len;
- if (caplen < sizeof(nflog_hdr_t) || length < sizeof(nflog_hdr_t))
- goto trunc;
+ ndo->ndo_protocol = "nflog";
+ ND_ICHECK_ZU(length, <, NFLOG_HDR_LEN);
ND_TCHECK_SIZE(hdr);
- if (hdr->nflog_version != 0) {
- ND_PRINT("version %u (unknown)", hdr->nflog_version);
- return h_size;
+ ndo->ndo_ll_hdr_len += NFLOG_HDR_LEN;
+
+ if (GET_U_1(hdr->nflog_version) != 0) {
+ ND_PRINT("version %u (unknown)", GET_U_1(hdr->nflog_version));
+ return;
}
if (ndo->ndo_eflag)
nflog_hdr_print(ndo, hdr, length);
- p += sizeof(nflog_hdr_t);
- length -= sizeof(nflog_hdr_t);
- caplen -= sizeof(nflog_hdr_t);
+ p += NFLOG_HDR_LEN;
+ length -= NFLOG_HDR_LEN;
+ caplen -= NFLOG_HDR_LEN;
- while (length > 0) {
+ while (length != 0) {
const nflog_tlv_t *tlv;
- /* We have some data. Do we have enough for the TLV header? */
- if (caplen < sizeof(nflog_tlv_t) || length < sizeof(nflog_tlv_t))
- goto trunc; /* No. */
-
+ ND_ICHECK_ZU(length, <, NFLOG_TLV_LEN);
tlv = (const nflog_tlv_t *) p;
+ /* Do we have enough data for the TLV header? */
ND_TCHECK_SIZE(tlv);
- size = tlv->tlv_length;
+ size = GET_HE_U_2(tlv->tlv_length);
if (size % 4 != 0)
size += 4 - size % 4;
/* Is the TLV's length less than the minimum? */
- if (size < sizeof(nflog_tlv_t))
- goto trunc; /* Yes. Give up now. */
+ ND_ICHECK_ZU(size, <, NFLOG_TLV_LEN);
+ ND_ICHECK_U(length, <, size);
/* Do we have enough data for the full TLV? */
- if (caplen < size || length < size)
- goto trunc; /* No. */
+ ND_TCHECK_LEN(tlv, size);
- if (tlv->tlv_type == NFULA_PAYLOAD) {
+ if (GET_HE_U_2(tlv->tlv_type) == NFULA_PAYLOAD) {
/*
* This TLV's data is the packet payload.
* Skip past the TLV header, and break out
* of the loop so we print the packet data.
*/
- p += sizeof(nflog_tlv_t);
- h_size += sizeof(nflog_tlv_t);
- length -= sizeof(nflog_tlv_t);
- caplen -= sizeof(nflog_tlv_t);
+ p += NFLOG_TLV_LEN;
+ h_size += NFLOG_TLV_LEN;
+ length -= NFLOG_TLV_LEN;
+ caplen -= NFLOG_TLV_LEN;
break;
}
caplen -= size;
}
- switch (hdr->nflog_family) {
+ switch (GET_U_1(hdr->nflog_family)) {
- case AF_INET:
+ case NFLOG_AF_INET:
ip_print(ndo, p, length);
break;
-#ifdef AF_INET6
- case AF_INET6:
+ case NFLOG_AF_INET6:
ip6_print(ndo, p, length);
break;
-#endif /* AF_INET6 */
default:
if (!ndo->ndo_eflag)
nflog_hdr_print(ndo, hdr,
- length + sizeof(nflog_hdr_t));
+ length + NFLOG_HDR_LEN);
if (!ndo->ndo_suppress_default_print)
ND_DEFAULTPRINT(p, caplen);
break;
}
- return h_size;
-trunc:
- ND_PRINT("%s", tstr);
- return h_size;
+ ndo->ndo_ll_hdr_len += h_size - NFLOG_HDR_LEN;
+ return;
+
+invalid:
+ nd_print_invalid(ndo);
}
-#endif /* defined(DLT_NFLOG) && defined(HAVE_PCAP_NFLOG_H) */
+#endif /* DLT_NFLOG */
projects / tcpdump / blobdiff