/* packet-nflog.c * Copyright 2011,2012 Jakub Zawadzki * * $Id$ * * Wireshark - Network traffic analyzer * By Gerald Combs * 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 #include #include #include /* nfulnl_attr_type enum from */ 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 #define BYTE_ORDER_HOST 3 static enum_val_t byte_order_types[] = { { "Auto", "Auto", BYTE_ORDER_AUTO }, { "Host", "Host", BYTE_ORDER_HOST }, { "LE", "Little Endian", BYTE_ORDER_LE }, { "BE", "Big Endian", BYTE_ORDER_BE }, { 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_timestamp = -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" }, */ /* ENC_NA has the same value as ENC_BIG_ENDIAN */ { 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; /* malformed */ if (tlv_len < 4) return 0; 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; case BYTE_ORDER_HOST: return (G_BYTE_ORDER == G_LITTLE_ENDIAN) ? ENC_LITTLE_ENDIAN : ENC_BIG_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; /* ENC_NA same as ENC_BIG_ENDIAN */ } 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; guint16 value_len; proto_tree *tlv_tree; /* malformed */ if (tlv_len < 4) return; value_len = tlv_len - 4; tlv_type = (val16_get(tvb, offset + 2) & 0x7fff); if (nflog_tree) { gboolean 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, enc); proto_tree_add_item(tlv_tree, hf_nflog_tlv_type, tvb, offset + 2, 2, enc); switch (tlv_type) { case WS_NFULA_PAYLOAD: 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_NA); 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) { nstime_t ts; ts.secs = tvb_get_ntoh64(tvb, offset + 4); /* XXX - add an "expert info" warning if this is >= 10^9? */ ts.nsecs = (int)tvb_get_ntoh64(tvb, offset + 12); proto_tree_add_time(tlv_tree, hf_nflog_tlv_timestamp, tvb, offset + 4, value_len, &ts); handled = TRUE; } break; } if (!handled) 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_HEX, 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_timestamp, { "Timestamp", "nflog.timestamp", FT_ABSOLUTE_TIME, ABSOLUTE_TIME_LOCAL, NULL, 0x00, "TLV Timestamp 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 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); }