/src/wireshark/epan/dissectors/packet-nflog.c

Source
/* packet-nflog.c
 * Copyright 2011,2012 Jakub Zawadzki <darkjames-ws@darkjames.pl>
 *
 * Wireshark - Network traffic analyzer
 * By Gerald Combs <gerald@wireshark.org>
 * Copyright 1998
 *
 * SPDX-License-Identifier: GPL-2.0-or-later
 */
#include "config.h"

#include <epan/etypes.h>
#include <epan/packet.h>
#include <wiretap/wtap.h>
#include <wsutil/ws_roundup.h>

#include "packet-arp.h"
#include "packet-netlink.h"

void proto_register_nflog(void);
void proto_reg_handoff_nflog(void);

/* nfulnl_attr_type enum from <linux/netfilter/nfnetlink_log.h> */
enum ws_nfulnl_attr_type {
    WS_NFULA_UNSPEC,
    WS_NFULA_PACKET_HDR,
    WS_NFULA_MARK,               /* __u32 nfmark */
    WS_NFULA_TIMESTAMP,          /* nfulnl_msg_packet_timestamp */
    WS_NFULA_IFINDEX_INDEV,      /* __u32 ifindex */
    WS_NFULA_IFINDEX_OUTDEV,     /* __u32 ifindex */
    WS_NFULA_IFINDEX_PHYSINDEV,  /* __u32 ifindex */
    WS_NFULA_IFINDEX_PHYSOUTDEV, /* __u32 ifindex */
    WS_NFULA_HWADDR,             /* nfulnl_msg_packet_hw */
    WS_NFULA_PAYLOAD,            /* opaque data payload */
    WS_NFULA_PREFIX,             /* string prefix */
    WS_NFULA_UID,                /* user id of socket */
    WS_NFULA_SEQ,                /* instance-local sequence number */
    WS_NFULA_SEQ_GLOBAL,         /* global sequence number */
    WS_NFULA_GID,                /* group id of socket */
    WS_NFULA_HWTYPE,             /* hardware type */
    WS_NFULA_HWHEADER,           /* hardware header */
    WS_NFULA_HWLEN,              /* hardware header length */
    WS_NFULA_CT,                 /* nfnetlink_conntrack.h */
    WS_NFULA_CT_INFO,            /* enum ip_conntrack_info */
};

static const value_string nflog_tlv_vals[] = {
    { WS_NFULA_UNSPEC,             "NFULA_UNSPEC" },
    { WS_NFULA_PACKET_HDR,         "NFULA_PACKET_HDR" },
    { WS_NFULA_MARK,               "NFULA_MARK" },
    { WS_NFULA_TIMESTAMP,          "NFULA_TIMESTAMP" },
    { WS_NFULA_IFINDEX_INDEV,      "NFULA_IFINDEX_INDEV" },
    { WS_NFULA_IFINDEX_OUTDEV,     "NFULA_IFINDEX_OUTDEV" },
    { WS_NFULA_IFINDEX_PHYSINDEV,  "NFULA_IFINDEX_PHYSINDEV" },
    { WS_NFULA_IFINDEX_PHYSOUTDEV, "NFULA_IFINDEX_PHYSOUTDEV" },
    { WS_NFULA_HWADDR,             "NFULA_HWADDR" },
    { WS_NFULA_PAYLOAD,            "NFULA_PAYLOAD" },
    { WS_NFULA_PREFIX,             "NFULA_PREFIX" },
    { WS_NFULA_UID,                "NFULA_UID" },
    { WS_NFULA_SEQ,                "NFULA_SEQ" },
    { WS_NFULA_SEQ_GLOBAL,         "NFULA_SEQ_GLOBAL" },
    { WS_NFULA_GID,                "NFULA_GID" },
    { WS_NFULA_HWTYPE,             "NFULA_HWTYPE" },
    { WS_NFULA_HWHEADER,           "NFULA_HWHEADER" },
    { WS_NFULA_HWLEN,              "NFULA_HWLEN" },
    { WS_NFULA_CT,                 "NFULA_CT" },
    { WS_NFULA_CT_INFO,            "NFULA_CT_INFO" },
    { 0, NULL }
};

static int proto_nflog;

static int hf_nflog_tlv_ct;
static int hf_nflog_tlv_ct_info;
static int hf_nflog_family;
static int hf_nflog_resid;
static int hf_nflog_tlv;
static int hf_nflog_tlv_gid;
static int hf_nflog_tlv_hook;
static int hf_nflog_tlv_hw_type;
static int hf_nflog_tlv_hwheader_len;
static int hf_nflog_tlv_hwprotocol;
static int hf_nflog_tlv_ifindex_indev;
static int hf_nflog_tlv_ifindex_outdev;
static int hf_nflog_tlv_ifindex_physindev;
static int hf_nflog_tlv_ifindex_physoutdev;
static int hf_nflog_tlv_length;
static int hf_nflog_tlv_prefix;
static int hf_nflog_tlv_timestamp;
static int hf_nflog_tlv_type;
static int hf_nflog_tlv_uid;
static int hf_nflog_tlv_unknown;
static int hf_nflog_version;

static int ett_nflog;
static int ett_nflog_tlv;

static dissector_handle_t ip_handle;
static dissector_handle_t ip6_handle;
static dissector_handle_t eth_handle;
static dissector_table_t ethertype_table;
static dissector_handle_t nflog_handle;

static bool eth_ip_layout_inside = true;

/* The TLV length and type are in the byte order of the host that
   captured the packet, given by tlv_encoding. */
static int
dissect_nflog_common(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, unsigned tlv_encoding)
{
    const int start_tlv_offset = 4;

    proto_tree *nflog_tree = NULL;
    proto_item *ti;

    unsigned offset = 0;

    struct {
        proto_tree *parent;
        tvbuff_t   *buffer;
    } payload = {NULL, NULL}, hwheader = {NULL, NULL};

    int pf;
    uint16_t hw_protocol = 0;

    col_set_str(pinfo->cinfo, COL_PROTOCOL, "NFLOG");
    col_clear(pinfo->cinfo, COL_INFO);

    pf = tvb_get_uint8(tvb, 0);

    /* Header */
    if (proto_field_is_referenced(tree, proto_nflog)) {
        ti = proto_tree_add_item(tree, proto_nflog, tvb, 0, -1, ENC_NA);
        nflog_tree = proto_item_add_subtree(ti, ett_nflog);

        proto_tree_add_item(nflog_tree, hf_nflog_family, tvb, offset, 1, ENC_NA);
        offset += 1;

        proto_tree_add_item(nflog_tree, hf_nflog_version, tvb, offset, 1, ENC_NA);
        offset += 1;

        proto_tree_add_item(nflog_tree, hf_nflog_resid, tvb, offset, 2, ENC_BIG_ENDIAN);
        /*offset += 2;*/
    }

    offset = start_tlv_offset;
    /* TLVs */
    while (tvb_reported_length_remaining(tvb, offset) >= 4) {
        uint16_t tlv_len = tvb_get_uint16(tvb, offset + 0, tlv_encoding);
        uint16_t tlv_type;
        uint16_t value_len;

        proto_tree *tlv_tree;

        /* malformed */
        if (tlv_len < 4)
            return offset;

        value_len = tlv_len - 4;
        tlv_type = (tvb_get_uint16(tvb, offset + 2, tlv_encoding) & 0x7fff);

        bool handled = false;
        ti = proto_tree_add_bytes_format(nflog_tree, hf_nflog_tlv,
                         tvb, offset, tlv_len, NULL,
                         "TLV Type: %s (%u), Length: %u",
                         val_to_str_const(tlv_type, nflog_tlv_vals, "Unknown"),
                         tlv_type, tlv_len);
        tlv_tree = proto_item_add_subtree(ti, ett_nflog_tlv);
        proto_tree_add_item(tlv_tree, hf_nflog_tlv_length, tvb, offset + 0, 2, tlv_encoding);
        proto_tree_add_item(tlv_tree, hf_nflog_tlv_type, tvb, offset + 2, 2, tlv_encoding);
        switch (tlv_type) {
            case WS_NFULA_PACKET_HDR:
                if (value_len == 4) {
                    proto_tree_add_item(tlv_tree, hf_nflog_tlv_hwprotocol,
                                tvb, offset + 4, 2, ENC_BIG_ENDIAN);
                    proto_tree_add_item(tlv_tree, hf_nflog_tlv_hook,
                                tvb, offset + 6, 1, ENC_NA);
                    hw_protocol = tvb_get_ntohs(tvb, offset + 4);
                    handled = true;
                }
                break;
            case WS_NFULA_IFINDEX_INDEV:
                if (value_len == 4) {
                    proto_tree_add_item(tlv_tree, hf_nflog_tlv_ifindex_indev, tvb, offset + 4, value_len, ENC_BIG_ENDIAN);
                    handled = true;
                }
                break;
            case WS_NFULA_IFINDEX_OUTDEV:
                if (value_len == 4) {
                    proto_tree_add_item(tlv_tree, hf_nflog_tlv_ifindex_outdev, tvb, offset + 4, value_len, ENC_BIG_ENDIAN);
                    handled = true;
                }
                break;
            case WS_NFULA_IFINDEX_PHYSINDEV:
                if (value_len == 4) {
                    proto_tree_add_item(tlv_tree, hf_nflog_tlv_ifindex_physindev, tvb, offset + 4, value_len, ENC_BIG_ENDIAN);
                    handled = true;
                }
                break;
            case WS_NFULA_IFINDEX_PHYSOUTDEV:
                if (value_len == 4) {
                    proto_tree_add_item(tlv_tree, hf_nflog_tlv_ifindex_physoutdev, tvb, offset + 4, value_len, ENC_BIG_ENDIAN);
                    handled = true;
                }
                break;
            case WS_NFULA_PAYLOAD:
                payload.buffer = tvb_new_subset_length(tvb, offset + 4, value_len);
                payload.parent = tlv_tree;
                handled = true;
                break;
            case WS_NFULA_PREFIX:
                if (value_len >= 1) {
                    proto_tree_add_item(tlv_tree, hf_nflog_tlv_prefix,
                                tvb, offset + 4, value_len, ENC_ASCII);
                    handled = true;
                }
                break;
            case WS_NFULA_UID:
                if (value_len == 4) {
                    proto_tree_add_item(tlv_tree, hf_nflog_tlv_uid,
                                tvb, offset + 4, value_len, ENC_BIG_ENDIAN);
                    handled = true;
                }
                break;
            case WS_NFULA_GID:
                if (value_len == 4) {
                    proto_tree_add_item(tlv_tree, hf_nflog_tlv_gid,
                                tvb, offset + 4, value_len, ENC_BIG_ENDIAN);
                    handled = true;
                }
                break;
            case WS_NFULA_TIMESTAMP:
                if (value_len == 16) {
                    /*
                     * 64-bit seconds and 64-bit microseconds.
                     *
                     * XXX - add an "expert info" warning if the
                     * microseconds are >= 10^6?
                     */
                    proto_tree_add_item(tlv_tree, hf_nflog_tlv_timestamp,
                                tvb, offset + 4, value_len,
                                ENC_TIME_SECS_USECS|ENC_BIG_ENDIAN);
                    handled = true;
                }
                break;
            case WS_NFULA_HWTYPE:
                if (value_len == 2) {
                    proto_tree_add_item(tlv_tree, hf_nflog_tlv_hw_type,
                                tvb, offset + 4, value_len, ENC_BIG_ENDIAN);
                    handled = true;
                }
                break;
            case WS_NFULA_HWHEADER:
                hwheader.buffer = tvb_new_subset_length(tvb, offset + 4, value_len);
                hwheader.parent = tlv_tree;
                handled = true;
                break;
            case WS_NFULA_HWLEN:
                if (value_len == 2 || value_len == 4) {
                    proto_tree_add_item(tlv_tree, hf_nflog_tlv_hwheader_len,
                                tvb, offset + 4, value_len, ENC_BIG_ENDIAN);
                    handled = true;
                }
                break;
            case WS_NFULA_CT:
                if (value_len > 0) {
                    proto_tree_add_item(tlv_tree, hf_nflog_tlv_ct,
                                tvb, offset + 4, value_len, ENC_ASCII);
                    handled = true;
                }
                break;
            case WS_NFULA_CT_INFO:
                if (value_len == 4) {
                    proto_tree_add_item(tlv_tree, hf_nflog_tlv_ct_info,
                                tvb, offset + 4, value_len, ENC_BIG_ENDIAN);
                    handled = true;
                }
                break;
        }

        if (!handled)
                proto_tree_add_item(tlv_tree, hf_nflog_tlv_unknown,
                                    tvb, offset + 4, value_len, ENC_NA);
        offset += WS_ROUNDUP_4(tlv_len); /* next TLV aligned to 4B */
    }

    if (hwheader.buffer && eth_handle) {
        proto_tree *parent = eth_ip_layout_inside ? hwheader.parent : tree;
        // for others it is not guaranteed to be full, just for avoiding errors
        if (hw_protocol == ETHERTYPE_IP) {
            call_dissector(eth_handle, hwheader.buffer, pinfo, parent);
        } else {
            call_data_dissector(hwheader.buffer, pinfo, parent);
        }
    }

    if (payload.buffer) {
        proto_tree *parent = eth_ip_layout_inside ? payload.parent : tree;
               if (hw_protocol) {
            if (!dissector_try_uint(ethertype_table, hw_protocol, payload.buffer, pinfo, parent))
                call_data_dissector(payload.buffer, pinfo, parent);
        } else {
            switch (pf) {
                /* Note: NFPROTO_INET is not supposed to appear here, it is mapped
                 * to NFPROTO_IPV4 or NFPROTO_IPV6 */
                case WS_NFPROTO_IPV4:
                    call_dissector(ip_handle, payload.buffer, pinfo, parent);
                    break;
                case WS_NFPROTO_IPV6:
                    call_dissector(ip6_handle, payload.buffer, pinfo, parent);
                    break;
                default:
                    call_data_dissector(payload.buffer, pinfo, parent);
                    break;
            }
        }
    }
    return tvb_captured_length(tvb);
}

/* LINKTYPE_NFLOG: wiretap has byte-swapped the TLV length and type into
   the byte order of the reading host. */
static int
dissect_nflog(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_)
{
    return dissect_nflog_common(tvb, pinfo, tree, ENC_HOST_ENDIAN);
}

/* Called from Netlink (netlink-netfilter ULOG), with the Netlink byte
   order in the packet_netlink_data. */
static int
dissect_nflog_netlink(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data)
{
    struct packet_netlink_data *nl_data = (struct packet_netlink_data *)data;

    if (nl_data && nl_data->magic == PACKET_NETLINK_MAGIC)
        return dissect_nflog_common(tvb, pinfo, tree, (unsigned)nl_data->encoding);
    return dissect_nflog_common(tvb, pinfo, tree, ENC_HOST_ENDIAN);
}

void
proto_register_nflog(void)
{
    static hf_register_info hf[] = {
        { &hf_nflog_family,
            { "Family", "nflog.family",
              FT_UINT8, BASE_DEC, VALS(nfproto_family_vals), 0x00,
              NULL, HFILL }
        },
        { &hf_nflog_version,
            { "Version", "nflog.version",
              FT_UINT8, BASE_DEC, NULL, 0x00,
              NULL, HFILL }
        },
        { &hf_nflog_resid,
            { "Resource id", "nflog.res_id",
              FT_UINT16, BASE_DEC, NULL, 0x00,
              NULL, HFILL }
        },
        { &hf_nflog_tlv,
            { "TLV", "nflog.tlv",
              FT_BYTES, BASE_NONE, NULL, 0x00,
              NULL, HFILL }
        },
        { &hf_nflog_tlv_length,
            { "Length", "nflog.tlv_length",
              FT_UINT16, BASE_DEC, NULL, 0x00,
              "TLV Length", HFILL }
        },
        { &hf_nflog_tlv_type,
            { "Type", "nflog.tlv_type",
              FT_UINT16, BASE_DEC, VALS(nflog_tlv_vals), 0x7fff,
              "TLV Type", HFILL }
        },
        { &hf_nflog_tlv_hwprotocol,
            { "HW protocol", "nflog.protocol",
              FT_UINT16, BASE_HEX, VALS(etype_vals), 0x00,
              NULL, HFILL }
        },
        { &hf_nflog_tlv_hw_type,
            { "HW Type", "nflog.hwtype",
              FT_UINT16, BASE_DEC, VALS(arp_hrd_vals), 0x00,
              NULL, HFILL }
        },
        { &hf_nflog_tlv_hwheader_len,
            { "Hardware header length", "nflog.hwhdr_len",
              FT_UINT16, BASE_DEC, NULL, 0x00, NULL, HFILL }
        },
        { &hf_nflog_tlv_hook,
            { "Netfilter hook", "nflog.hook",
              FT_UINT8, BASE_DEC, VALS(netfilter_hooks_vals), 0x00,
              NULL, HFILL }
        },
        { &hf_nflog_tlv_ifindex_indev,
            { "IFINDEX_INDEV", "nflog.ifindex_indev",
              FT_UINT32, BASE_DEC, NULL, 0x00,
              NULL, HFILL }
        },
        { &hf_nflog_tlv_ifindex_outdev,
            { "IFINDEX_OUTDEV", "nflog.ifindex_outdev",
              FT_UINT32, BASE_DEC, NULL, 0x00,
              NULL, HFILL }
        },
        { &hf_nflog_tlv_ifindex_physindev,
            { "IFINDEX_PHYSINDEV", "nflog.ifindex_physindev",
              FT_UINT32, BASE_DEC, NULL, 0x00,
              NULL, HFILL }
        },
        { &hf_nflog_tlv_ifindex_physoutdev,
            { "IFINDEX_PHYSOUTDEV", "nflog.ifindex_physoutdev",
              FT_UINT32, BASE_DEC, NULL, 0x00,
              NULL, HFILL }
        },
        { &hf_nflog_tlv_prefix,
            { "Prefix", "nflog.prefix",
              FT_STRINGZ, BASE_NONE, NULL, 0x00,
              "TLV Prefix Value", HFILL }
        },
        { &hf_nflog_tlv_uid,
            { "UID", "nflog.uid",
              FT_INT32, BASE_DEC, NULL, 0x00,
              "TLV UID Value", HFILL }
        },
        { &hf_nflog_tlv_gid,
            { "GID", "nflog.gid",
              FT_INT32, BASE_DEC, NULL, 0x00,
              "TLV GID Value", HFILL }
        },
        { &hf_nflog_tlv_timestamp,
            { "Timestamp", "nflog.timestamp",
              FT_ABSOLUTE_TIME, ABSOLUTE_TIME_LOCAL, NULL, 0x00,
              "TLV Timestamp Value", HFILL }
        },
        { &hf_nflog_tlv_ct_info,
            { "CT INFO", "nflog.ctinfo",
              FT_INT32, BASE_DEC, VALS(nfq_ctinfo_vals), 0x00,
              "TLV CT INFO", HFILL }
        },
        { &hf_nflog_tlv_ct,
            { "CT", "nflog.ct",
              FT_STRINGZ, BASE_NONE, NULL, 0x00,
              "TLV CT", HFILL }
        },
        { &hf_nflog_tlv_unknown,
            { "Value", "nflog.tlv_value",
              FT_BYTES, BASE_NONE, NULL, 0x00,
              "TLV Value", HFILL }
        },
    };

    static int *ett[] = {
        &ett_nflog,
        &ett_nflog_tlv
    };

    module_t *nflog_module;

    proto_nflog = proto_register_protocol("Linux Netfilter NFLOG", "NFLOG", "nflog");
    nflog_handle = register_dissector("nflog", dissect_nflog, proto_nflog);
    register_dissector_with_description("nflog_netlink", "NFLOG over Netlink", dissect_nflog_netlink, proto_nflog);
    proto_register_field_array(proto_nflog, hf, array_length(hf));
    proto_register_subtree_array(ett, array_length(ett));
    // user preferences
    nflog_module = prefs_register_protocol(proto_nflog, NULL);
    prefs_register_bool_preference(nflog_module, "eth_ip_layout_inside",
        "Place ip and eth inside",
        "Place ip and eth sections inside appropriate TLV's "
        "(payload and hw header respectively). If false, then place on top level",
        &eth_ip_layout_inside);
}

void
proto_reg_handoff_nflog(void)
{
    ip_handle  = find_dissector_add_dependency("ip", proto_nflog);
    ip6_handle = find_dissector_add_dependency("ipv6", proto_nflog);
    eth_handle = find_dissector_add_dependency("eth_header", proto_nflog);

    dissector_add_uint("wtap_encap", WTAP_ENCAP_NFLOG, nflog_handle);
    ethertype_table = find_dissector_table("ethertype");
}

/*
 * Editor modelines
 *
 * Local Variables:
 * c-basic-offset: 4
 * tab-width: 8
 * indent-tabs-mode: nil
 * End:
 *
 * ex: set shiftwidth=4 tabstop=8 expandtab:
 * :indentSize=4:tabSize=8:noTabs=true:
 */

Coverage Report

Created: 2026-11-12 07:01

Line	Count	Source
1		/* packet-nflog.c
2		* Copyright 2011,2012 Jakub Zawadzki <darkjames-ws@darkjames.pl>
3		*
4		* Wireshark - Network traffic analyzer
5		* By Gerald Combs <gerald@wireshark.org>
6		* Copyright 1998
7		*
8		* SPDX-License-Identifier: GPL-2.0-or-later
9		*/
10		#include "config.h"
11
12		#include <epan/etypes.h>
13		#include <epan/packet.h>
14		#include <wiretap/wtap.h>
15		#include <wsutil/ws_roundup.h>
16
17		#include "packet-arp.h"
18		#include "packet-netlink.h"
19
20		void proto_register_nflog(void);
21		void proto_reg_handoff_nflog(void);
22
23		/* nfulnl_attr_type enum from <linux/netfilter/nfnetlink_log.h> */
24		enum ws_nfulnl_attr_type {
25		WS_NFULA_UNSPEC,
26		WS_NFULA_PACKET_HDR,
27		WS_NFULA_MARK, /* __u32 nfmark */
28		WS_NFULA_TIMESTAMP, /* nfulnl_msg_packet_timestamp */
29		WS_NFULA_IFINDEX_INDEV, /* __u32 ifindex */
30		WS_NFULA_IFINDEX_OUTDEV, /* __u32 ifindex */
31		WS_NFULA_IFINDEX_PHYSINDEV, /* __u32 ifindex */
32		WS_NFULA_IFINDEX_PHYSOUTDEV, /* __u32 ifindex */
33		WS_NFULA_HWADDR, /* nfulnl_msg_packet_hw */
34		WS_NFULA_PAYLOAD, /* opaque data payload */
35		WS_NFULA_PREFIX, /* string prefix */
36		WS_NFULA_UID, /* user id of socket */
37		WS_NFULA_SEQ, /* instance-local sequence number */
38		WS_NFULA_SEQ_GLOBAL, /* global sequence number */
39		WS_NFULA_GID, /* group id of socket */
40		WS_NFULA_HWTYPE, /* hardware type */
41		WS_NFULA_HWHEADER, /* hardware header */
42		WS_NFULA_HWLEN, /* hardware header length */
43		WS_NFULA_CT, /* nfnetlink_conntrack.h */
44		WS_NFULA_CT_INFO, /* enum ip_conntrack_info */
45		};
46
47		static const value_string nflog_tlv_vals[] = {
48		{ WS_NFULA_UNSPEC, "NFULA_UNSPEC" },
49		{ WS_NFULA_PACKET_HDR, "NFULA_PACKET_HDR" },
50		{ WS_NFULA_MARK, "NFULA_MARK" },
51		{ WS_NFULA_TIMESTAMP, "NFULA_TIMESTAMP" },
52		{ WS_NFULA_IFINDEX_INDEV, "NFULA_IFINDEX_INDEV" },
53		{ WS_NFULA_IFINDEX_OUTDEV, "NFULA_IFINDEX_OUTDEV" },
54		{ WS_NFULA_IFINDEX_PHYSINDEV, "NFULA_IFINDEX_PHYSINDEV" },
55		{ WS_NFULA_IFINDEX_PHYSOUTDEV, "NFULA_IFINDEX_PHYSOUTDEV" },
56		{ WS_NFULA_HWADDR, "NFULA_HWADDR" },
57		{ WS_NFULA_PAYLOAD, "NFULA_PAYLOAD" },
58		{ WS_NFULA_PREFIX, "NFULA_PREFIX" },
59		{ WS_NFULA_UID, "NFULA_UID" },
60		{ WS_NFULA_SEQ, "NFULA_SEQ" },
61		{ WS_NFULA_SEQ_GLOBAL, "NFULA_SEQ_GLOBAL" },
62		{ WS_NFULA_GID, "NFULA_GID" },
63		{ WS_NFULA_HWTYPE, "NFULA_HWTYPE" },
64		{ WS_NFULA_HWHEADER, "NFULA_HWHEADER" },
65		{ WS_NFULA_HWLEN, "NFULA_HWLEN" },
66		{ WS_NFULA_CT, "NFULA_CT" },
67		{ WS_NFULA_CT_INFO, "NFULA_CT_INFO" },
68		{ 0, NULL }
69		};
70
71		static int proto_nflog;
72
73		static int hf_nflog_tlv_ct;
74		static int hf_nflog_tlv_ct_info;
75		static int hf_nflog_family;
76		static int hf_nflog_resid;
77		static int hf_nflog_tlv;
78		static int hf_nflog_tlv_gid;
79		static int hf_nflog_tlv_hook;
80		static int hf_nflog_tlv_hw_type;
81		static int hf_nflog_tlv_hwheader_len;
82		static int hf_nflog_tlv_hwprotocol;
83		static int hf_nflog_tlv_ifindex_indev;
84		static int hf_nflog_tlv_ifindex_outdev;
85		static int hf_nflog_tlv_ifindex_physindev;
86		static int hf_nflog_tlv_ifindex_physoutdev;
87		static int hf_nflog_tlv_length;
88		static int hf_nflog_tlv_prefix;
89		static int hf_nflog_tlv_timestamp;
90		static int hf_nflog_tlv_type;
91		static int hf_nflog_tlv_uid;
92		static int hf_nflog_tlv_unknown;
93		static int hf_nflog_version;
94
95		static int ett_nflog;
96		static int ett_nflog_tlv;
97
98		static dissector_handle_t ip_handle;
99		static dissector_handle_t ip6_handle;
100		static dissector_handle_t eth_handle;
101		static dissector_table_t ethertype_table;
102		static dissector_handle_t nflog_handle;
103
104		static bool eth_ip_layout_inside = true;
105
106		/* The TLV length and type are in the byte order of the host that
107		captured the packet, given by tlv_encoding. */
108		static int
109		dissect_nflog_common(tvbuff_t tvb, packet_info pinfo, proto_tree *tree, unsigned tlv_encoding)
110	0	{
111	0	const int start_tlv_offset = 4;
112
113	0	proto_tree *nflog_tree = NULL;
114	0	proto_item *ti;
115
116	0	unsigned offset = 0;
117
118	0	struct {
119	0	proto_tree *parent;
120	0	tvbuff_t *buffer;
121	0	} payload = {NULL, NULL}, hwheader = {NULL, NULL};
122
123	0	int pf;
124	0	uint16_t hw_protocol = 0;
125
126	0	col_set_str(pinfo->cinfo, COL_PROTOCOL, "NFLOG");
127	0	col_clear(pinfo->cinfo, COL_INFO);
128
129	0	pf = tvb_get_uint8(tvb, 0);
130
131		/* Header */
132	0	if (proto_field_is_referenced(tree, proto_nflog)) {
133	0	ti = proto_tree_add_item(tree, proto_nflog, tvb, 0, -1, ENC_NA);
134	0	nflog_tree = proto_item_add_subtree(ti, ett_nflog);
135
136	0	proto_tree_add_item(nflog_tree, hf_nflog_family, tvb, offset, 1, ENC_NA);
137	0	offset += 1;
138
139	0	proto_tree_add_item(nflog_tree, hf_nflog_version, tvb, offset, 1, ENC_NA);
140	0	offset += 1;
141
142	0	proto_tree_add_item(nflog_tree, hf_nflog_resid, tvb, offset, 2, ENC_BIG_ENDIAN);
143		/offset += 2;/
144	0	}
145
146	0	offset = start_tlv_offset;
147		/* TLVs */
148	0	while (tvb_reported_length_remaining(tvb, offset) >= 4) {
149	0	uint16_t tlv_len = tvb_get_uint16(tvb, offset + 0, tlv_encoding);
150	0	uint16_t tlv_type;
151	0	uint16_t value_len;
152
153	0	proto_tree *tlv_tree;
154
155		/* malformed */
156	0	if (tlv_len < 4)
157	0	return offset;
158
159	0	value_len = tlv_len - 4;
160	0	tlv_type = (tvb_get_uint16(tvb, offset + 2, tlv_encoding) & 0x7fff);
161
162	0	bool handled = false;
163	0	ti = proto_tree_add_bytes_format(nflog_tree, hf_nflog_tlv,
164	0	tvb, offset, tlv_len, NULL,
165	0	"TLV Type: %s (%u), Length: %u",
166	0	val_to_str_const(tlv_type, nflog_tlv_vals, "Unknown"),
167	0	tlv_type, tlv_len);
168	0	tlv_tree = proto_item_add_subtree(ti, ett_nflog_tlv);
169	0	proto_tree_add_item(tlv_tree, hf_nflog_tlv_length, tvb, offset + 0, 2, tlv_encoding);
170	0	proto_tree_add_item(tlv_tree, hf_nflog_tlv_type, tvb, offset + 2, 2, tlv_encoding);
171	0	switch (tlv_type) {
172	0	case WS_NFULA_PACKET_HDR:
173	0	if (value_len == 4) {
174	0	proto_tree_add_item(tlv_tree, hf_nflog_tlv_hwprotocol,
175	0	tvb, offset + 4, 2, ENC_BIG_ENDIAN);
176	0	proto_tree_add_item(tlv_tree, hf_nflog_tlv_hook,
177	0	tvb, offset + 6, 1, ENC_NA);
178	0	hw_protocol = tvb_get_ntohs(tvb, offset + 4);
179	0	handled = true;
180	0	}
181	0	break;
182	0	case WS_NFULA_IFINDEX_INDEV:
183	0	if (value_len == 4) {
184	0	proto_tree_add_item(tlv_tree, hf_nflog_tlv_ifindex_indev, tvb, offset + 4, value_len, ENC_BIG_ENDIAN);
185	0	handled = true;
186	0	}
187	0	break;
188	0	case WS_NFULA_IFINDEX_OUTDEV:
189	0	if (value_len == 4) {
190	0	proto_tree_add_item(tlv_tree, hf_nflog_tlv_ifindex_outdev, tvb, offset + 4, value_len, ENC_BIG_ENDIAN);
191	0	handled = true;
192	0	}
193	0	break;
194	0	case WS_NFULA_IFINDEX_PHYSINDEV:
195	0	if (value_len == 4) {
196	0	proto_tree_add_item(tlv_tree, hf_nflog_tlv_ifindex_physindev, tvb, offset + 4, value_len, ENC_BIG_ENDIAN);
197	0	handled = true;
198	0	}
199	0	break;
200	0	case WS_NFULA_IFINDEX_PHYSOUTDEV:
201	0	if (value_len == 4) {
202	0	proto_tree_add_item(tlv_tree, hf_nflog_tlv_ifindex_physoutdev, tvb, offset + 4, value_len, ENC_BIG_ENDIAN);
203	0	handled = true;
204	0	}
205	0	break;
206	0	case WS_NFULA_PAYLOAD:
207	0	payload.buffer = tvb_new_subset_length(tvb, offset + 4, value_len);
208	0	payload.parent = tlv_tree;
209	0	handled = true;
210	0	break;
211	0	case WS_NFULA_PREFIX:
212	0	if (value_len >= 1) {
213	0	proto_tree_add_item(tlv_tree, hf_nflog_tlv_prefix,
214	0	tvb, offset + 4, value_len, ENC_ASCII);
215	0	handled = true;
216	0	}
217	0	break;
218	0	case WS_NFULA_UID:
219	0	if (value_len == 4) {
220	0	proto_tree_add_item(tlv_tree, hf_nflog_tlv_uid,
221	0	tvb, offset + 4, value_len, ENC_BIG_ENDIAN);
222	0	handled = true;
223	0	}
224	0	break;
225	0	case WS_NFULA_GID:
226	0	if (value_len == 4) {
227	0	proto_tree_add_item(tlv_tree, hf_nflog_tlv_gid,
228	0	tvb, offset + 4, value_len, ENC_BIG_ENDIAN);
229	0	handled = true;
230	0	}
231	0	break;
232	0	case WS_NFULA_TIMESTAMP:
233	0	if (value_len == 16) {
234		/*
235		* 64-bit seconds and 64-bit microseconds.
236		*
237		* XXX - add an "expert info" warning if the
238		* microseconds are >= 10^6?
239		*/
240	0	proto_tree_add_item(tlv_tree, hf_nflog_tlv_timestamp,
241	0	tvb, offset + 4, value_len,
242	0	ENC_TIME_SECS_USECS\|ENC_BIG_ENDIAN);
243	0	handled = true;
244	0	}
245	0	break;
246	0	case WS_NFULA_HWTYPE:
247	0	if (value_len == 2) {
248	0	proto_tree_add_item(tlv_tree, hf_nflog_tlv_hw_type,
249	0	tvb, offset + 4, value_len, ENC_BIG_ENDIAN);
250	0	handled = true;
251	0	}
252	0	break;
253	0	case WS_NFULA_HWHEADER:
254	0	hwheader.buffer = tvb_new_subset_length(tvb, offset + 4, value_len);
255	0	hwheader.parent = tlv_tree;
256	0	handled = true;
257	0	break;
258	0	case WS_NFULA_HWLEN:
259	0	if (value_len == 2 \|\| value_len == 4) {
260	0	proto_tree_add_item(tlv_tree, hf_nflog_tlv_hwheader_len,
261	0	tvb, offset + 4, value_len, ENC_BIG_ENDIAN);
262	0	handled = true;
263	0	}
264	0	break;
265	0	case WS_NFULA_CT:
266	0	if (value_len > 0) {
267	0	proto_tree_add_item(tlv_tree, hf_nflog_tlv_ct,
268	0	tvb, offset + 4, value_len, ENC_ASCII);
269	0	handled = true;
270	0	}
271	0	break;
272	0	case WS_NFULA_CT_INFO:
273	0	if (value_len == 4) {
274	0	proto_tree_add_item(tlv_tree, hf_nflog_tlv_ct_info,
275	0	tvb, offset + 4, value_len, ENC_BIG_ENDIAN);
276	0	handled = true;
277	0	}
278	0	break;
279	0	}
280
281	0	if (!handled)
282	0	proto_tree_add_item(tlv_tree, hf_nflog_tlv_unknown,
283	0	tvb, offset + 4, value_len, ENC_NA);
284	0	offset += WS_ROUNDUP_4(tlv_len); /* next TLV aligned to 4B */
285	0	}
286
287	0	if (hwheader.buffer && eth_handle) {
288	0	proto_tree *parent = eth_ip_layout_inside ? hwheader.parent : tree;
289		// for others it is not guaranteed to be full, just for avoiding errors
290	0	if (hw_protocol == ETHERTYPE_IP) {
291	0	call_dissector(eth_handle, hwheader.buffer, pinfo, parent);
292	0	} else {
293	0	call_data_dissector(hwheader.buffer, pinfo, parent);
294	0	}
295	0	}
296
297	0	if (payload.buffer) {
298	0	proto_tree *parent = eth_ip_layout_inside ? payload.parent : tree;
299	0	if (hw_protocol) {
300	0	if (!dissector_try_uint(ethertype_table, hw_protocol, payload.buffer, pinfo, parent))
301	0	call_data_dissector(payload.buffer, pinfo, parent);
302	0	} else {
303	0	switch (pf) {
304		/* Note: NFPROTO_INET is not supposed to appear here, it is mapped
305		* to NFPROTO_IPV4 or NFPROTO_IPV6 */
306	0	case WS_NFPROTO_IPV4:
307	0	call_dissector(ip_handle, payload.buffer, pinfo, parent);
308	0	break;
309	0	case WS_NFPROTO_IPV6:
310	0	call_dissector(ip6_handle, payload.buffer, pinfo, parent);
311	0	break;
312	0	default:
313	0	call_data_dissector(payload.buffer, pinfo, parent);
314	0	break;
315	0	}
316	0	}
317	0	}
318	0	return tvb_captured_length(tvb);
319	0	}
320
321		/* LINKTYPE_NFLOG: wiretap has byte-swapped the TLV length and type into
322		the byte order of the reading host. */
323		static int
324		dissect_nflog(tvbuff_t tvb, packet_info pinfo, proto_tree tree, void data _U_)
325	0	{
326	0	return dissect_nflog_common(tvb, pinfo, tree, ENC_HOST_ENDIAN);
327	0	}
328
329		/* Called from Netlink (netlink-netfilter ULOG), with the Netlink byte
330		order in the packet_netlink_data. */
331		static int
332		dissect_nflog_netlink(tvbuff_t tvb, packet_info pinfo, proto_tree tree, void data)
333	0	{
334	0	struct packet_netlink_data nl_data = (struct packet_netlink_data )data;
335
336	0	if (nl_data && nl_data->magic == PACKET_NETLINK_MAGIC)
337	0	return dissect_nflog_common(tvb, pinfo, tree, (unsigned)nl_data->encoding);
338	0	return dissect_nflog_common(tvb, pinfo, tree, ENC_HOST_ENDIAN);
339	0	}
340
341		void
342		proto_register_nflog(void)
343	16	{
344	16	static hf_register_info hf[] = {
345	16	{ &hf_nflog_family,
346	16	{ "Family", "nflog.family",
347	16	FT_UINT8, BASE_DEC, VALS(nfproto_family_vals), 0x00,
348	16	NULL, HFILL }
349	16	},
350	16	{ &hf_nflog_version,
351	16	{ "Version", "nflog.version",
352	16	FT_UINT8, BASE_DEC, NULL, 0x00,
353	16	NULL, HFILL }
354	16	},
355	16	{ &hf_nflog_resid,
356	16	{ "Resource id", "nflog.res_id",
357	16	FT_UINT16, BASE_DEC, NULL, 0x00,
358	16	NULL, HFILL }
359	16	},
360	16	{ &hf_nflog_tlv,
361	16	{ "TLV", "nflog.tlv",
362	16	FT_BYTES, BASE_NONE, NULL, 0x00,
363	16	NULL, HFILL }
364	16	},
365	16	{ &hf_nflog_tlv_length,
366	16	{ "Length", "nflog.tlv_length",
367	16	FT_UINT16, BASE_DEC, NULL, 0x00,
368	16	"TLV Length", HFILL }
369	16	},
370	16	{ &hf_nflog_tlv_type,
371	16	{ "Type", "nflog.tlv_type",
372	16	FT_UINT16, BASE_DEC, VALS(nflog_tlv_vals), 0x7fff,
373	16	"TLV Type", HFILL }
374	16	},
375	16	{ &hf_nflog_tlv_hwprotocol,
376	16	{ "HW protocol", "nflog.protocol",
377	16	FT_UINT16, BASE_HEX, VALS(etype_vals), 0x00,
378	16	NULL, HFILL }
379	16	},
380	16	{ &hf_nflog_tlv_hw_type,
381	16	{ "HW Type", "nflog.hwtype",
382	16	FT_UINT16, BASE_DEC, VALS(arp_hrd_vals), 0x00,
383	16	NULL, HFILL }
384	16	},
385	16	{ &hf_nflog_tlv_hwheader_len,
386	16	{ "Hardware header length", "nflog.hwhdr_len",
387	16	FT_UINT16, BASE_DEC, NULL, 0x00, NULL, HFILL }
388	16	},
389	16	{ &hf_nflog_tlv_hook,
390	16	{ "Netfilter hook", "nflog.hook",
391	16	FT_UINT8, BASE_DEC, VALS(netfilter_hooks_vals), 0x00,
392	16	NULL, HFILL }
393	16	},
394	16	{ &hf_nflog_tlv_ifindex_indev,
395	16	{ "IFINDEX_INDEV", "nflog.ifindex_indev",
396	16	FT_UINT32, BASE_DEC, NULL, 0x00,
397	16	NULL, HFILL }
398	16	},
399	16	{ &hf_nflog_tlv_ifindex_outdev,
400	16	{ "IFINDEX_OUTDEV", "nflog.ifindex_outdev",
401	16	FT_UINT32, BASE_DEC, NULL, 0x00,
402	16	NULL, HFILL }
403	16	},
404	16	{ &hf_nflog_tlv_ifindex_physindev,
405	16	{ "IFINDEX_PHYSINDEV", "nflog.ifindex_physindev",
406	16	FT_UINT32, BASE_DEC, NULL, 0x00,
407	16	NULL, HFILL }
408	16	},
409	16	{ &hf_nflog_tlv_ifindex_physoutdev,
410	16	{ "IFINDEX_PHYSOUTDEV", "nflog.ifindex_physoutdev",
411	16	FT_UINT32, BASE_DEC, NULL, 0x00,
412	16	NULL, HFILL }
413	16	},
414	16	{ &hf_nflog_tlv_prefix,
415	16	{ "Prefix", "nflog.prefix",
416	16	FT_STRINGZ, BASE_NONE, NULL, 0x00,
417	16	"TLV Prefix Value", HFILL }
418	16	},
419	16	{ &hf_nflog_tlv_uid,
420	16	{ "UID", "nflog.uid",
421	16	FT_INT32, BASE_DEC, NULL, 0x00,
422	16	"TLV UID Value", HFILL }
423	16	},
424	16	{ &hf_nflog_tlv_gid,
425	16	{ "GID", "nflog.gid",
426	16	FT_INT32, BASE_DEC, NULL, 0x00,
427	16	"TLV GID Value", HFILL }
428	16	},
429	16	{ &hf_nflog_tlv_timestamp,
430	16	{ "Timestamp", "nflog.timestamp",
431	16	FT_ABSOLUTE_TIME, ABSOLUTE_TIME_LOCAL, NULL, 0x00,
432	16	"TLV Timestamp Value", HFILL }
433	16	},
434	16	{ &hf_nflog_tlv_ct_info,
435	16	{ "CT INFO", "nflog.ctinfo",
436	16	FT_INT32, BASE_DEC, VALS(nfq_ctinfo_vals), 0x00,
437	16	"TLV CT INFO", HFILL }
438	16	},
439	16	{ &hf_nflog_tlv_ct,
440	16	{ "CT", "nflog.ct",
441	16	FT_STRINGZ, BASE_NONE, NULL, 0x00,
442	16	"TLV CT", HFILL }
443	16	},
444	16	{ &hf_nflog_tlv_unknown,
445	16	{ "Value", "nflog.tlv_value",
446	16	FT_BYTES, BASE_NONE, NULL, 0x00,
447	16	"TLV Value", HFILL }
448	16	},
449	16	};
450
451	16	static int *ett[] = {
452	16	&ett_nflog,
453	16	&ett_nflog_tlv
454	16	};
455
456	16	module_t *nflog_module;
457
458	16	proto_nflog = proto_register_protocol("Linux Netfilter NFLOG", "NFLOG", "nflog");
459	16	nflog_handle = register_dissector("nflog", dissect_nflog, proto_nflog);
460	16	register_dissector_with_description("nflog_netlink", "NFLOG over Netlink", dissect_nflog_netlink, proto_nflog);
461	16	proto_register_field_array(proto_nflog, hf, array_length(hf));
462	16	proto_register_subtree_array(ett, array_length(ett));
463		// user preferences
464	16	nflog_module = prefs_register_protocol(proto_nflog, NULL);
465	16	prefs_register_bool_preference(nflog_module, "eth_ip_layout_inside",
466	16	"Place ip and eth inside",
467	16	"Place ip and eth sections inside appropriate TLV's "
468	16	"(payload and hw header respectively). If false, then place on top level",
469	16	&eth_ip_layout_inside);
470	16	}
471
472		void
473		proto_reg_handoff_nflog(void)
474	16	{
475	16	ip_handle = find_dissector_add_dependency("ip", proto_nflog);
476	16	ip6_handle = find_dissector_add_dependency("ipv6", proto_nflog);
477	16	eth_handle = find_dissector_add_dependency("eth_header", proto_nflog);
478
479	16	dissector_add_uint("wtap_encap", WTAP_ENCAP_NFLOG, nflog_handle);
480	16	ethertype_table = find_dissector_table("ethertype");
481	16	}
482
483		/*
484		* Editor modelines
485		*
486		* Local Variables:
487		* c-basic-offset: 4
488		* tab-width: 8
489		* indent-tabs-mode: nil
490		* End:
491		*
492		* ex: set shiftwidth=4 tabstop=8 expandtab:
493		* :indentSize=4:tabSize=8:noTabs=true:
494		*/