+/*
+ * Copyright (c) 2013, Petar Alilovic,
+ * Faculty of Electrical Engineering and Computing, University of Zagreb
+ * All rights reserved
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * * Redistributions of source code must retain the above copyright notice,
+ * this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ */
+
+/* \summary: DLT_NFLOG printer */
+
#ifdef HAVE_CONFIG_H
-#include "config.h"
+#include <config.h>
#endif
-#include <tcpdump-stdinc.h>
-
-#include <stdio.h>
-#include <pcap.h>
+#include "netdissect-stdinc.h"
#include "netdissect.h"
-#include "interface.h"
+#include "extract.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 pakets 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[] = {
+ { NFLOG_AF_INET, "IPv4" },
+ { NFLOG_AF_INET6, "IPv6" },
+ { 0, NULL }
+};
+
static void
-nflog_print(struct netdissect_options *ndo, const u_char *p, u_int length, u_int caplen _U_)
+nflog_hdr_print(netdissect_options *ndo, const nflog_hdr_t *hdr, u_int length)
{
- ip_print(ndo, p, length);
- return;
+ 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 (%u)",
+ tok2str(nflog_values, "Unknown",
+ GET_U_1(hdr->nflog_family)),
+ GET_U_1(hdr->nflog_family));
+ } else {
+ ND_PRINT(", %s",
+ tok2str(nflog_values,
+ "Unknown NFLOG (0x%02x)",
+ GET_U_1(hdr->nflog_family)));
+ }
+
+ ND_PRINT(", length %u: ", length);
}
-u_int
-nflog_if_print(struct netdissect_options *ndo,
+void
+nflog_if_print(netdissect_options *ndo,
const struct pcap_pkthdr *h, const u_char *p)
{
- if (h->len < 104 || h->caplen < 104) {
- ND_PRINT((ndo, "[!nflog]"));
- return h->caplen;
+ const nflog_hdr_t *hdr = (const nflog_hdr_t *)p;
+ uint16_t size;
+ uint16_t h_size = NFLOG_HDR_LEN;
+ u_int caplen = h->caplen;
+ u_int length = h->len;
+
+ ndo->ndo_protocol = "nflog";
+ if (caplen < NFLOG_HDR_LEN) {
+ nd_print_trunc(ndo);
+ ndo->ndo_ll_hdr_len += caplen;
+ return;
+ }
+ ndo->ndo_ll_hdr_len += NFLOG_HDR_LEN;
+
+ ND_TCHECK_SIZE(hdr);
+ if (GET_U_1(hdr->nflog_version) != 0) {
+ ND_PRINT("version %u (unknown)", GET_U_1(hdr->nflog_version));
+ return;
}
- nflog_print(ndo, p + 104, h->len - 104, h->caplen - 104);
+ if (ndo->ndo_eflag)
+ nflog_hdr_print(ndo, hdr, length);
+
+ p += NFLOG_HDR_LEN;
+ length -= NFLOG_HDR_LEN;
+ caplen -= NFLOG_HDR_LEN;
+
+ while (length > 0) {
+ const nflog_tlv_t *tlv;
+
+ /* We have some data. Do we have enough for the TLV header? */
+ if (caplen < NFLOG_TLV_LEN)
+ goto trunc; /* No. */
+
+ tlv = (const nflog_tlv_t *) p;
+ ND_TCHECK_SIZE(tlv);
+ size = GET_HE_U_2(tlv->tlv_length);
+ if (size % 4 != 0)
+ size += 4 - size % 4;
- return 104;
+ /* Is the TLV's length less than the minimum? */
+ if (size < NFLOG_TLV_LEN)
+ goto trunc; /* Yes. Give up now. */
+
+ /* Do we have enough data for the full TLV? */
+ if (caplen < size)
+ goto trunc; /* No. */
+
+ 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 += NFLOG_TLV_LEN;
+ h_size += NFLOG_TLV_LEN;
+ length -= NFLOG_TLV_LEN;
+ caplen -= NFLOG_TLV_LEN;
+ break;
+ }
+
+ p += size;
+ h_size += size;
+ length -= size;
+ caplen -= size;
+ }
+
+ switch (GET_U_1(hdr->nflog_family)) {
+
+ case NFLOG_AF_INET:
+ ip_print(ndo, p, length);
+ break;
+
+ case NFLOG_AF_INET6:
+ ip6_print(ndo, p, length);
+ break;
+
+ default:
+ if (!ndo->ndo_eflag)
+ nflog_hdr_print(ndo, hdr,
+ length + NFLOG_HDR_LEN);
+
+ if (!ndo->ndo_suppress_default_print)
+ ND_DEFAULTPRINT(p, caplen);
+ break;
+ }
+
+ ndo->ndo_ll_hdr_len += h_size - NFLOG_HDR_LEN;
+ return;
+trunc:
+ nd_print_trunc(ndo);
+ ndo->ndo_ll_hdr_len += h_size - NFLOG_HDR_LEN;
}
#endif /* DLT_NFLOG */
projects / tcpdump / blobdiff