diff options
author | Jakub Zawadzki <darkjames-ws@darkjames.pl> | 2012-03-31 17:29:41 +0000 |
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committer | Jakub Zawadzki <darkjames-ws@darkjames.pl> | 2012-03-31 17:29:41 +0000 |
commit | bb8afe3f688c137bc275354b4ffc36f766e154e5 (patch) | |
tree | 7b393c2a4aab53724c6cc4a618f9f53da1b08922 /epan/dissectors/packet-nflog.c | |
parent | 56ef1c48177f440def325f8bbefcd7f90cb9d96c (diff) |
Add initial support for dissecting packets encapsulated in Netfilter LOG (DLT_NFLOG=239).
svn path=/trunk/; revision=41872
Diffstat (limited to 'epan/dissectors/packet-nflog.c')
-rw-r--r-- | epan/dissectors/packet-nflog.c | 348 |
1 files changed, 348 insertions, 0 deletions
diff --git a/epan/dissectors/packet-nflog.c b/epan/dissectors/packet-nflog.c new file mode 100644 index 0000000000..ef44143dc9 --- /dev/null +++ b/epan/dissectors/packet-nflog.c @@ -0,0 +1,348 @@ +/* packet-nflog.c + * Copyright 2011,2012 Jekub Zawadzki <darkjames-ws@darkjames.pl> + * + * $Id$ + * + * Wireshark - Network traffic analyzer + * By Gerald Combs <gerald@wireshark.org> + * Copyright 1998 + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + */ + +#ifdef HAVE_CONFIG_H +# include "config.h" +#endif + +#include <glib.h> + +#include <epan/packet.h> +#include <epan/prefs.h> +#include <epan/aftypes.h> + +/* 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 */ +}; + +#define BYTE_ORDER_AUTO 0 +#define BYTE_ORDER_BE 1 +#define BYTE_ORDER_LE 2 + +static enum_val_t byte_order_types[] = { + { "Auto", "Auto", BYTE_ORDER_AUTO }, + { "LE", "LE", BYTE_ORDER_BE }, + { "BE", "BE", BYTE_ORDER_LE }, + { NULL, NULL, 0 } +}; + +static gint nflog_byte_order = BYTE_ORDER_AUTO; + +static int proto_nflog = -1; + +static int ett_nflog = -1; +static int ett_nflog_tlv = -1; + +static int hf_nflog_family = -1; +static int hf_nflog_version = -1; +static int hf_nflog_resid = -1; +static int hf_nflog_encoding = -1; + +static int hf_nflog_tlv = -1; +static int hf_nflog_tlv_length = -1; +static int hf_nflog_tlv_type = -1; +static int hf_nflog_tlv_prefix = -1; +static int hf_nflog_tlv_uid = -1; +static int hf_nflog_tlv_gid = -1; +static int hf_nflog_tlv_unknown = -1; + +static dissector_handle_t ip_handle; +static dissector_handle_t ip6_handle; +static dissector_handle_t data_handle; + +static const value_string _linux_family_vals[] = { + { LINUX_AF_INET, "IP" }, + { LINUX_AF_INET6, "IPv6" }, + { 0, NULL } +}; + +static const value_string _encoding_vals[] = { + { ENC_BIG_ENDIAN, "Big Endian" }, + { ENC_LITTLE_ENDIAN, "Little Endian" }, + { ENC_NA, "Unknown" }, + { 0, NULL } +}; + +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" }, + { 0, NULL } +}; + +static int +nflog_tvb_test_order(tvbuff_t *tvb, int offset, guint16 (*val16_get)(tvbuff_t *, int)) +{ + while (tvb_length_remaining(tvb, offset) > 4) { + guint16 tlv_len = val16_get(tvb, offset + 0); + guint16 tlv_type = (val16_get(tvb, offset + 2) & 0x7fff); + + if (tlv_type >= 0x100) + break; + + if (tlv_type) + return 1; + + offset += ((tlv_len + 3) & ~3); /* next TLV aligned to 4B */ + } + return 0; +} + +static int +nflog_tvb_byte_order(tvbuff_t *tvb, int tlv_offset) +{ + switch (nflog_byte_order) { + case BYTE_ORDER_BE: + return ENC_BIG_ENDIAN; + + case BYTE_ORDER_LE: + return ENC_LITTLE_ENDIAN; + } + + if (nflog_tvb_test_order(tvb, tlv_offset, tvb_get_ntohs)) + return ENC_BIG_ENDIAN; + + if (nflog_tvb_test_order(tvb, tlv_offset, tvb_get_letohs)) + return ENC_LITTLE_ENDIAN; + + return ENC_NA; +} + +static void +dissect_nflog(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree) +{ + const int start_tlv_offset = 4; + + proto_tree *nflog_tree = NULL; + proto_item *ti; + + int offset = 0; + + tvbuff_t *next_tvb = NULL; + int aftype; + + int enc; + guint16 (*val16_get)(tvbuff_t *, int); + + col_set_str(pinfo->cinfo, COL_PROTOCOL, "NFLOG"); + col_clear(pinfo->cinfo, COL_INFO); + + aftype = tvb_get_guint8(tvb, 0); + enc = nflog_tvb_byte_order(tvb, start_tlv_offset); + switch (enc) { + case ENC_LITTLE_ENDIAN: + val16_get = tvb_get_letohs; + break; + + case ENC_BIG_ENDIAN: + default: + val16_get = tvb_get_ntohs; + break; + } + + /* 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; + + ti = proto_tree_add_uint(nflog_tree, hf_nflog_encoding, tvb, offset, tvb_length_remaining(tvb, offset), enc); + PROTO_ITEM_SET_GENERATED(ti); + } + + offset = start_tlv_offset; + /* TLVs */ + while (tvb_length_remaining(tvb, offset) >= 4) { + guint16 tlv_len = val16_get(tvb, offset + 0); + guint16 tlv_type = (val16_get(tvb, offset + 2) & 0x7fff); + guint16 value_len = tlv_len - 4; + + proto_tree *tlv_tree; + + if (nflog_tree) { + 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, enc); + proto_tree_add_item(tlv_tree, hf_nflog_tlv_type, tvb, offset + 2, 2, enc); + switch (tlv_type) { + case WS_NFULA_PAYLOAD: + break; + case WS_NFULA_PREFIX: + /* value_len >= 1 */ + proto_tree_add_item(tlv_tree, hf_nflog_tlv_prefix, tvb, offset + 4, value_len, ENC_NA); + break; + case WS_NFULA_UID: + /* value_len == 4 */ + proto_tree_add_item(tlv_tree, hf_nflog_tlv_uid, tvb, offset + 4, value_len, ENC_BIG_ENDIAN); + break; + case WS_NFULA_GID: + /* value_len == 4 */ + proto_tree_add_item(tlv_tree, hf_nflog_tlv_gid, tvb, offset + 4, value_len, ENC_BIG_ENDIAN); + break; + /* ... */ + + default: + proto_tree_add_item(tlv_tree, hf_nflog_tlv_unknown, tvb, offset + 4, value_len, ENC_NA); + } + } + + if (tlv_type == WS_NFULA_PAYLOAD) + next_tvb = tvb_new_subset(tvb, offset + 4, value_len, value_len); + + offset += ((tlv_len + 3) & ~3); /* next TLV aligned to 4B */ + } + + if (next_tvb) { + switch (aftype) { + case LINUX_AF_INET: + call_dissector(ip_handle, next_tvb, pinfo, tree); + break; + case LINUX_AF_INET6: + call_dissector(ip6_handle, next_tvb, pinfo, tree); + break; + default: + call_dissector(data_handle, next_tvb, pinfo, tree); + break; + } + } +} + +void +proto_register_nflog(void) +{ + static hf_register_info hf[] = { + /* Header */ + { &hf_nflog_family, + { "Family", "nflog.family", FT_UINT8, BASE_DEC, VALS(_linux_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_encoding, + { "Encoding", "nflog.encoding", FT_UINT32, BASE_NONE, VALS(_encoding_vals), 0x00, NULL, HFILL } + }, + + /* TLV */ + { &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 } + }, + /* TLV values */ + { &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_unknown, + { "Value", "nflog.tlv_value", FT_BYTES, BASE_NONE, NULL, 0x00, "TLV Value", HFILL } + }, + }; + + static gint *ett[] = { + &ett_nflog, + &ett_nflog_tlv + }; + + module_t *pref; + + proto_nflog = proto_register_protocol("Linux Netfilter LOG (NFLOG)", "NFLOG", "nflog"); + + pref = prefs_register_protocol(proto_nflog, NULL); + prefs_register_enum_preference(pref, "byte_order_type", "Byte Order", "Byte Order", &nflog_byte_order, byte_order_types, FALSE); + + register_dissector("nflog", dissect_nflog, proto_nflog); + + proto_register_field_array(proto_nflog, hf, array_length(hf)); + proto_register_subtree_array(ett, array_length(ett)); + +} + +void +proto_reg_handoff_nflog(void) +{ + dissector_handle_t nflog_handle; + + ip_handle = find_dissector("ip"); + ip6_handle = find_dissector("ipv6"); + data_handle = find_dissector("data"); + + nflog_handle = find_dissector("nflog"); + dissector_add_uint("wtap_encap", WTAP_ENCAP_NFLOG, nflog_handle); +} + |