From e4ba6dbc3f1e76890b22773807ea37fe8fa2b1bc Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Wed, 10 Apr 2024 22:34:10 +0200 Subject: Adding upstream version 4.2.2. Signed-off-by: Daniel Baumann --- epan/dissectors/packet-stt.c | 925 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 925 insertions(+) create mode 100644 epan/dissectors/packet-stt.c (limited to 'epan/dissectors/packet-stt.c') diff --git a/epan/dissectors/packet-stt.c b/epan/dissectors/packet-stt.c new file mode 100644 index 00000000..26f55159 --- /dev/null +++ b/epan/dissectors/packet-stt.c @@ -0,0 +1,925 @@ +/* packet-stt.c + * + * Routines for Stateless Transport Tunneling (STT) packet dissection + * Remi Vichery + * + * Wireshark - Network traffic analyzer + * By Gerald Combs + * Copyright 1998 Gerald Combs + * + * SPDX-License-Identifier: GPL-2.0-or-later + * + * Protocol ref: + * https://tools.ietf.org/html/draft-davie-stt-07 + */ + +#include "config.h" + +#include +#include +#include +#include +#include +#include +#include + +#include "packet-ip.h" + +static gboolean pref_reassemble = TRUE; +static gboolean pref_check_checksum = FALSE; + +/* IANA ref: + * https://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.xhtml + */ +#define TCP_PORT_STT 7471 + +/* Length of entire overloaded TCP header. */ +#define STT_TCP_HDR_LEN 20 + +/* Sum of STT header field sizes plus trailing padding. */ +#define STT_HEADER_SIZE 18 + +#define STT_TCP_OFF_DPORT 2 +#define STT_TCP_OFF_PKT_LEN 4 +#define STT_TCP_OFF_SEG_OFF 6 +#define STT_TCP_OFF_PKT_ID 8 + +#define STT_PCP_MASK 0xE000 +#define STT_V_MASK 0x1000 +#define STT_VLANID_MASK 0x0FFF + +#define FLAG_OFFLOAD_MASK 0x02 + +void proto_register_stt(void); +void proto_reg_handoff_stt(void); + +static int proto_stt = -1; + +static int hf_stt_stream_id = -1; +static int hf_stt_dport = -1; +static int hf_stt_pkt_len = -1; +static int hf_stt_seg_off = -1; +static int hf_stt_pkt_id = -1; +static int hf_stt_checksum = -1; +static int hf_stt_checksum_status = -1; +static int hf_stt_tcp_data = -1; +static int hf_stt_tcp_data_offset = -1; +static int hf_stt_tcp_flags = -1; +static int hf_stt_tcp_rsvd = -1; +static int hf_stt_tcp_ns = -1; +static int hf_stt_tcp_cwr = -1; +static int hf_stt_tcp_ece = -1; +static int hf_stt_tcp_urg = -1; +static int hf_stt_tcp_ack = -1; +static int hf_stt_tcp_psh = -1; +static int hf_stt_tcp_rst = -1; +static int hf_stt_tcp_syn = -1; +static int hf_stt_tcp_fin = -1; +static int hf_stt_tcp_window = -1; +static int hf_stt_tcp_urg_ptr = -1; + +static int hf_stt_version = -1; +static int hf_stt_flags = -1; +static int hf_stt_flag_rsvd = -1; +static int hf_stt_flag_tcp = -1; +static int hf_stt_flag_ipv4 = -1; +static int hf_stt_flag_partial = -1; +static int hf_stt_flag_verified = -1; +static int hf_stt_l4_offset = -1; +static int hf_stt_reserved_8 = -1; +static int hf_stt_mss = -1; +static int hf_stt_vlan = -1; +static int hf_stt_pcp = -1; +static int hf_stt_v = -1; +static int hf_stt_vlan_id= -1; +static int hf_stt_context_id = -1; +static int hf_stt_padding = -1; + +static int hf_segments = -1; +static int hf_segment = -1; +static int hf_segment_overlap = -1; +static int hf_segment_overlap_conflict = -1; +static int hf_segment_multiple_tails = -1; +static int hf_segment_too_long_fragment = -1; +static int hf_segment_error = -1; +static int hf_segment_count = -1; +static int hf_reassembled_in = -1; +static int hf_reassembled_length = -1; + +static int ett_stt = -1; +static int ett_stt_tcp_data = -1; +static int ett_stt_tcp_flags = -1; +static int ett_stt_flgs = -1; +static int ett_stt_vlan = -1; +static int ett_segment = -1; +static int ett_segments = -1; + +static reassembly_table stt_reassembly_table; + +static expert_field ei_stt_ver_unknown = EI_INIT; +static expert_field ei_stt_checksum_bad = EI_INIT; +static expert_field ei_stt_data_offset_bad = EI_INIT; +static expert_field ei_stt_l4_offset = EI_INIT; +static expert_field ei_stt_mss = EI_INIT; + +static dissector_handle_t eth_handle; + +/* From Table G-2 of IEEE standard 802.1Q-2005 */ +static const value_string pri_vals[] = { + { 1, "Background" }, + { 0, "Best Effort (default)" }, + { 2, "Excellent Effort" }, + { 3, "Critical Applications" }, + { 4, "Video, < 100ms latency and jitter" }, + { 5, "Voice, < 10ms latency and jitter" }, + { 6, "Internetwork Control" }, + { 7, "Network Control" }, + { 0, NULL } +}; + +static const fragment_items frag_items = { + &ett_segment, + &ett_segments, + &hf_segments, + &hf_segment, + &hf_segment_overlap, + &hf_segment_overlap_conflict, + &hf_segment_multiple_tails, + &hf_segment_too_long_fragment, + &hf_segment_error, + &hf_segment_count, + &hf_reassembled_in, + &hf_reassembled_length, + NULL, /* Reassembled data */ + "STT segments" +}; + +static tvbuff_t * +handle_segment(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, + guint32 pkt_id, guint16 pkt_len, guint16 seg_off) +{ + fragment_head *frags; + int offset; + guint32 frag_data_len; + gboolean more_frags; + + /* Skip fake TCP header after the first segment. */ + if (seg_off == 0) { + offset = 0; + } else { + offset = STT_TCP_HDR_LEN; + /* We saved the TCP header on the first packet (only), which skews the + * segment offset. */ + seg_off += STT_TCP_HDR_LEN; + } + + frag_data_len = tvb_reported_length_remaining(tvb, offset); + more_frags = seg_off + frag_data_len < pkt_len; + + frags = fragment_add_check(&stt_reassembly_table, tvb, offset, pinfo, + pkt_id, NULL, seg_off, frag_data_len, + more_frags); + + /* Update reassembly fields in UI if reassembly is complete. */ + if (frags) { + return process_reassembled_data(tvb, offset, pinfo, "Reassembled STT", + frags, &frag_items, NULL, tree); + } + + return NULL; +} + +static void +dissect_stt_checksum(tvbuff_t *tvb, packet_info *pinfo, proto_tree *stt_tree) +{ + gboolean can_checksum = !pinfo->fragmented && + tvb_bytes_exist(tvb, 0, tvb_reported_length(tvb)); + + if (can_checksum && pref_check_checksum) { + vec_t cksum_vec[4]; + guint32 phdr[2]; + + /* Set up the fields of the pseudo-header. */ + SET_CKSUM_VEC_PTR(cksum_vec[0], (const guint8 *)pinfo->src.data, + pinfo->src.len); + SET_CKSUM_VEC_PTR(cksum_vec[1], (const guint8 *)pinfo->dst.data, + pinfo->dst.len); + switch (pinfo->src.type) { + case AT_IPv4: + phdr[0] = g_htonl((IP_PROTO_TCP<<16) + tvb_reported_length(tvb)); + SET_CKSUM_VEC_PTR(cksum_vec[2], (const guint8 *)phdr, 4); + break; + + case AT_IPv6: + phdr[0] = g_htonl(tvb_reported_length(tvb)); + phdr[1] = g_htonl(IP_PROTO_TCP); + SET_CKSUM_VEC_PTR(cksum_vec[2], (const guint8 *)phdr, 8); + break; + + default: + /* STT runs only atop IPv4 and IPv6.... */ + DISSECTOR_ASSERT_NOT_REACHED(); + break; + } + SET_CKSUM_VEC_TVB(cksum_vec[3], tvb, 0, tvb_reported_length(tvb)); + + proto_tree_add_checksum(stt_tree, tvb, 16, hf_stt_checksum, hf_stt_checksum_status, &ei_stt_checksum_bad, pinfo, + in_cksum(cksum_vec, 4), ENC_BIG_ENDIAN, PROTO_CHECKSUM_VERIFY); + } else { + proto_tree_add_checksum(stt_tree, tvb, 16, hf_stt_checksum, hf_stt_checksum_status, &ei_stt_checksum_bad, pinfo, + 0, ENC_BIG_ENDIAN, PROTO_CHECKSUM_NO_FLAGS); + } +} + +static int +dissect_tcp_flags(proto_tree *tree, tvbuff_t *tvb, int offset) +{ + static int * const flags[] = { + &hf_stt_tcp_rsvd, + &hf_stt_tcp_ns, + &hf_stt_tcp_cwr, + &hf_stt_tcp_ece, + &hf_stt_tcp_urg, + &hf_stt_tcp_ack, + &hf_stt_tcp_psh, + &hf_stt_tcp_rst, + &hf_stt_tcp_syn, + &hf_stt_tcp_fin, + NULL + }; + + proto_tree_add_bitmask(tree, tvb, offset, hf_stt_tcp_flags, + ett_stt_tcp_flags, flags, ENC_BIG_ENDIAN); + offset += 2; + + return offset; +} + +static void +dissect_tcp_tree(tvbuff_t *tvb, packet_info *pinfo, proto_tree *stt_tree) +{ + int offset = 0; + proto_tree *tcp_tree; + proto_item *tcp_item, *data_offset_item; + int data_offset; + + proto_tree_add_item(stt_tree, hf_stt_stream_id, tvb, offset, 2, ENC_BIG_ENDIAN); + offset += 2; + + proto_tree_add_item(stt_tree, hf_stt_dport, tvb, offset, 2, ENC_BIG_ENDIAN); + offset += 2; + + proto_tree_add_item(stt_tree, hf_stt_pkt_len, tvb, offset, 2, ENC_BIG_ENDIAN); + offset += 2; + + proto_tree_add_item(stt_tree, hf_stt_seg_off, tvb, offset, 2, ENC_BIG_ENDIAN); + offset += 2; + + proto_tree_add_item(stt_tree, hf_stt_pkt_id, tvb, offset, 4, ENC_BIG_ENDIAN); + offset += 4; + + tcp_item = proto_tree_add_item(stt_tree, hf_stt_tcp_data, tvb, offset, + 8, ENC_NA); + tcp_tree = proto_item_add_subtree(tcp_item, ett_stt_tcp_data); + proto_item_set_text(tcp_item, "TCP Data"); + + data_offset = hi_nibble(tvb_get_guint8(tvb, offset)) * 4; + data_offset_item = proto_tree_add_uint(tcp_tree, + hf_stt_tcp_data_offset, + tvb, offset, 1, + data_offset); + if (data_offset != STT_TCP_HDR_LEN) { + expert_add_info(pinfo, data_offset_item, &ei_stt_data_offset_bad); + } + + offset = dissect_tcp_flags(tcp_tree, tvb, offset); + + proto_tree_add_item(tcp_tree, hf_stt_tcp_window, tvb, offset, 2, + ENC_BIG_ENDIAN); + offset += 2; + + dissect_stt_checksum(tvb, pinfo, stt_tree); + offset += 2; + + proto_tree_add_item(tcp_tree, hf_stt_tcp_urg_ptr, tvb, offset, 2, + ENC_BIG_ENDIAN); +} + +static int +dissect_stt_flags(proto_tree *tree, tvbuff_t *tvb, int offset) +{ + static int * const flags[] = { + &hf_stt_flag_rsvd, + &hf_stt_flag_tcp, + &hf_stt_flag_ipv4, + &hf_stt_flag_partial, + &hf_stt_flag_verified, + NULL + }; + + proto_tree_add_bitmask(tree, tvb, offset, hf_stt_flags, + ett_stt_flgs, flags, ENC_BIG_ENDIAN); + offset += 1; + + return offset; +} + +static void +dissect_stt_tree(tvbuff_t *tvb, packet_info *pinfo, proto_tree *stt_tree, + proto_item *stt_item) +{ + proto_tree *vlan_tree; + proto_item *ver_item, *l4_offset_item, *vlan_item, *mss_item; + guint8 flags; + guint32 version, l4_offset, mss, attributes; + guint64 context_id; + int offset = STT_TCP_HDR_LEN; + + /* + 0 1 2 3 + 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Version | Flags | L4 Offset | Reserved | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Max. Segment Size | PCP |V| VLAN ID | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | | + + Context ID (64 bits) + + | | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Padding | Data | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + + | | + */ + + /* Protocol version */ + ver_item = proto_tree_add_item_ret_uint(stt_tree, hf_stt_version, tvb, + offset, 1, ENC_BIG_ENDIAN, &version); + if (version != 0) { + expert_add_info_format(pinfo, ver_item, &ei_stt_ver_unknown, + "Unknown version %u", version); + col_add_fstr(pinfo->cinfo, COL_INFO, "Unknown STT version %u", version); + } + offset++; + + /* Flags */ + flags = tvb_get_guint8(tvb, offset); + offset = dissect_stt_flags(stt_tree, tvb, offset); + + /* Layer 4 offset */ + l4_offset_item = proto_tree_add_item_ret_uint(stt_tree, hf_stt_l4_offset, + tvb, offset, 1, + ENC_BIG_ENDIAN, &l4_offset); + /* Display an error if offset is != 0 when offloading is not in use */ + if ( !(flags & FLAG_OFFLOAD_MASK) && (l4_offset != 0) ) { + expert_add_info_format(pinfo, l4_offset_item, &ei_stt_l4_offset, "Incorrect offset, should be equal to zero"); + } + /* Display an error if offset equals 0 when there is offloading */ + if ( (flags & FLAG_OFFLOAD_MASK) && (l4_offset == 0) ) { + expert_add_info_format(pinfo, l4_offset_item, &ei_stt_l4_offset, "Incorrect offset, should be greater than zero"); + } + offset ++; + + /* Reserved field (1 byte). MUST be 0 on transmission, + ignored on receipt. */ + proto_tree_add_item(stt_tree, hf_stt_reserved_8, tvb, offset, 1, + ENC_BIG_ENDIAN); + offset ++; + + /* Maximum Segment Size. MUST be 0 if segmentation offload + is not in use. */ + mss_item = proto_tree_add_item_ret_uint(stt_tree, hf_stt_mss, tvb, + offset, 2, ENC_BIG_ENDIAN, &mss); + /* Display an error if MSS is != 0 when offloading is not in use */ + if ( !(flags & FLAG_OFFLOAD_MASK) && (mss != 0) ) { + expert_add_info_format(pinfo, mss_item, &ei_stt_mss, "Incorrect max segment size, should be equal to zero"); + } + offset += 2; + + /* Tag Control Information like header. If V flag is set, it + indicates the presence of a valid VLAN ID in the following field + and valid PCP in the preceding field. */ + vlan_item = proto_tree_add_item_ret_uint(stt_tree, hf_stt_vlan, tvb, offset, + 2, ENC_BIG_ENDIAN, &attributes); + vlan_tree = proto_item_add_subtree(vlan_item, ett_stt_vlan); + proto_item_set_text(vlan_item, "VLAN Priority %u, ID %u", + (attributes >> 13), (attributes & STT_VLANID_MASK)); + + proto_tree_add_item(vlan_tree, hf_stt_pcp, tvb, offset, 2, ENC_BIG_ENDIAN); + proto_tree_add_item(vlan_tree, hf_stt_v, tvb, offset, 2, ENC_BIG_ENDIAN); + proto_tree_add_item(vlan_tree, hf_stt_vlan_id, tvb, offset, 2, ENC_BIG_ENDIAN); + if (attributes & STT_V_MASK) { + /* Display priority code point and VLAN ID when V flag is set */ + proto_item_append_text(stt_item, ", Priority: %u, VLAN ID: %u", + attributes >> 13, + attributes & STT_VLANID_MASK); + } + /* Show if any part of this is set to aid debugging bad implementations. */ + if (attributes == 0) { + proto_item_set_hidden(vlan_item); + } + offset += 2; + + /* Context ID */ + context_id = tvb_get_ntoh64(tvb, offset); + proto_tree_add_item(stt_tree, hf_stt_context_id, tvb, offset, 8, ENC_BIG_ENDIAN); + proto_item_append_text(stt_item, ", Context ID: 0x%" PRIx64, + context_id); + offset += 8; + + /* Padding */ + proto_tree_add_item(stt_tree, hf_stt_padding, tvb, offset, + 2, ENC_BIG_ENDIAN); +} + +static void +dissect_stt(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree) +{ + proto_item *stt_item; + proto_tree *stt_tree; + tvbuff_t *next_tvb; + guint16 seg_off, pkt_len, rx_bytes; + guint8 sub_off; + gboolean frag_save, is_seg; + + /* Make entry in Protocol column on summary display. */ + col_set_str(pinfo->cinfo, COL_PROTOCOL, "STT"); + col_clear(pinfo->cinfo, COL_INFO); + + stt_item = proto_tree_add_item(tree, proto_stt, tvb, 0, + STT_TCP_HDR_LEN, ENC_NA); + stt_tree = proto_item_add_subtree(stt_item, ett_stt); + + dissect_tcp_tree(tvb, pinfo, stt_tree); + + frag_save = pinfo->fragmented; + + seg_off = tvb_get_ntohs(tvb, STT_TCP_OFF_SEG_OFF); + pkt_len = tvb_get_ntohs(tvb, STT_TCP_OFF_PKT_LEN); + rx_bytes = tvb_reported_length_remaining(tvb, STT_TCP_HDR_LEN); + is_seg = pkt_len > rx_bytes; + + if (is_seg) { + guint32 pkt_id = tvb_get_ntohl(tvb, STT_TCP_OFF_PKT_ID); + + pinfo->fragmented = TRUE; + col_add_fstr(pinfo->cinfo, COL_INFO, + "STT Segment (ID: 0x%x Len: %hu, Off: %hu)", + pkt_id, pkt_len, seg_off); + + /* Reassemble segments unless the user has disabled reassembly. */ + if (pref_reassemble && tvb_bytes_exist(tvb, 0, rx_bytes)) { + tvbuff_t *reasm_tvb; + + reasm_tvb = handle_segment(tvb, pinfo, stt_tree, pkt_id, + pkt_len, seg_off); + if (reasm_tvb) { + tvb = reasm_tvb; + pinfo->fragmented = frag_save; + is_seg = FALSE; + } + } else if (seg_off == 0) { + /* If we're not reassembling, move ahead as if we have the + * whole frame. */ + is_seg = FALSE; + } + } + + /* Only full packets have a STT header (following the fake TCP header). */ + if (!is_seg) { + sub_off = STT_TCP_HDR_LEN + STT_HEADER_SIZE; + dissect_stt_tree(tvb, pinfo, stt_tree, stt_item); + } else { + sub_off = STT_TCP_HDR_LEN; + } + + if (seg_off == 0) { + proto_item_set_len(stt_item, sub_off); + } + next_tvb = tvb_new_subset_remaining(tvb, sub_off); + + /* Only dissect inner frame if not segmented or if we aren't + doing reassembly. */ + if (!is_seg) { + call_dissector(eth_handle, next_tvb, pinfo, tree); + } else { + call_data_dissector(next_tvb, pinfo, tree); + } + + pinfo->fragmented = frag_save; +} + +static gboolean +dissect_stt_heur(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, + void *iph) +{ + /* Make sure we at least have a TCP header */ + if (ws_ip_protocol(iph) != IP_PROTO_TCP || + tvb_captured_length(tvb) < STT_TCP_HDR_LEN) { + return FALSE; + } + + /* Check the TCP destination port */ + if (tvb_get_ntohs(tvb, STT_TCP_OFF_DPORT) != TCP_PORT_STT) { + return FALSE; + } + + dissect_stt(tvb, pinfo, tree); + return TRUE; +} + +/* Register STT with Wireshark */ +void +proto_register_stt(void) +{ + expert_module_t* expert_stt; + module_t *stt_prefs; + + static hf_register_info hf[] = { + /* Overloaded fake TCP header fields. */ + { &hf_stt_stream_id, + { "Stream ID", "stt.stream_id", + FT_UINT16, BASE_HEX, NULL, 0x0, + NULL, HFILL + }, + }, + { &hf_stt_dport, + { "Destination Port", "stt.dport", + FT_UINT16, BASE_DEC, NULL, 0x0, + NULL, HFILL + }, + }, + { &hf_stt_pkt_len, + { "Packet Length", "stt.pkt_len", + FT_UINT16, BASE_DEC, NULL, 0x0, + NULL, HFILL + }, + }, + { &hf_stt_seg_off, + { "Segment Offset", "stt.seg_off", + FT_UINT16, BASE_DEC, NULL, 0x0, + NULL, HFILL + }, + }, + { &hf_stt_pkt_id, + { "Packet ID", "stt.pkt_id", + FT_UINT32, BASE_HEX, NULL, 0x0, + NULL, HFILL + }, + }, + { &hf_stt_tcp_data, + { "TCP Data", "stt.tcp", + FT_BYTES, BASE_NONE, NULL, 0x0, + NULL, HFILL, + }, + }, + { &hf_stt_tcp_data_offset, + { "Data Offset", "stt.tcp.data_offset", + FT_UINT8, BASE_DEC|BASE_UNIT_STRING, &units_byte_bytes, 0x0, + NULL, HFILL, + }, + }, + { &hf_stt_tcp_flags, + { "Flags", "stt.tcp.flags", + FT_UINT16, BASE_HEX, NULL, 0x0FFF, + NULL, HFILL, + }, + }, + { &hf_stt_tcp_rsvd, + { "Reserved", "stt.tcp.flags.rsvd", + FT_BOOLEAN, 12, NULL, 0xE00, + NULL, HFILL, + }, + }, + { &hf_stt_tcp_ns, + { "Nonce", "stt.tcp.flags.ns", + FT_BOOLEAN, 12, NULL, 0x100, + NULL, HFILL, + }, + }, + { &hf_stt_tcp_cwr, + { "Congestion Window Reduced (CWR)", "stt.tcp.flags.cwr", + FT_BOOLEAN, 12, NULL, 0x080, + NULL, HFILL, + }, + }, + { &hf_stt_tcp_ece, + { "ECN-Echo", "stt.tcp.flags.ece", + FT_BOOLEAN, 12, NULL, 0x040, + NULL, HFILL, + }, + }, + { &hf_stt_tcp_urg, + { "Urgent", "stt.tcp.flags.urg", + FT_BOOLEAN, 12, NULL, 0x020, + NULL, HFILL, + }, + }, + { &hf_stt_tcp_ack, + { "Acknowledgement", "stt.tcp.flags.ack", + FT_BOOLEAN, 12, NULL, 0x010, + NULL, HFILL, + }, + }, + { &hf_stt_tcp_psh, + { "Push", "stt.tcp.flags.psh", + FT_BOOLEAN, 12, NULL, 0x008, + NULL, HFILL, + }, + }, + { &hf_stt_tcp_rst, + { "Reset", "stt.tcp.flags.rst", + FT_BOOLEAN, 12, NULL, 0x004, + NULL, HFILL, + }, + }, + { &hf_stt_tcp_syn, + { "Syn", "stt.tcp.flags.syn", + FT_BOOLEAN, 12, NULL, 0x002, + NULL, HFILL, + }, + }, + { &hf_stt_tcp_fin, + { "Fin", "stt.tcp.flags.fin", + FT_BOOLEAN, 12, NULL, 0x001, + NULL, HFILL, + }, + }, + { &hf_stt_tcp_window, + { "Window", "stt.tcp.window", + FT_UINT16, BASE_DEC, NULL, 0x0, + NULL, HFILL, + }, + }, + { &hf_stt_tcp_urg_ptr, + { "Urgent Pointer", "stt.tcp.urg_ptr", + FT_UINT16, BASE_DEC, NULL, 0x0, + NULL, HFILL, + }, + }, + + /* STT header fields. */ + { &hf_stt_version, + { "Version", "stt.version", + FT_UINT8, BASE_DEC, NULL, 0x0, + NULL, HFILL + }, + }, + { &hf_stt_flags, + { "Flags", "stt.flags", + FT_UINT8, BASE_HEX, NULL, 0x0, + NULL, HFILL, + }, + }, + { &hf_stt_flag_rsvd, + { "Reserved", "stt.flags.rsvd", + FT_BOOLEAN, 8, NULL, 0xF0, + NULL, HFILL, + }, + }, + { &hf_stt_flag_tcp, + { "TCP payload", "stt.flags.tcp", + FT_BOOLEAN, 8, NULL, 0x08, + NULL, HFILL, + }, + }, + { &hf_stt_flag_ipv4, + { "IPv4 packet", "stt.flags.ipv4", + FT_BOOLEAN, 8, NULL, 0x04, + NULL, HFILL, + }, + }, + { &hf_stt_flag_partial, + { "Checksum partial", "stt.flags.csum_partial", + FT_BOOLEAN, 8, NULL, 0x02, + NULL, HFILL, + }, + }, + { &hf_stt_flag_verified, + { "Checksum verified", "stt.flags.csum_verified", + FT_BOOLEAN, 8, NULL, 0x01, + NULL, HFILL, + }, + }, + { &hf_stt_l4_offset, + { "L4 Offset", "stt.l4offset", + FT_UINT8, BASE_DEC, NULL, 0x0, + NULL, HFILL, + }, + }, + { &hf_stt_reserved_8, + { "Reserved", "stt.reserved", + FT_UINT8, BASE_HEX, NULL, 0x0, + NULL, HFILL, + }, + }, + { &hf_stt_mss, + { "Max Segment Size", "stt.mss", + FT_UINT16, BASE_DEC, NULL, 0x0, + NULL, HFILL, + }, + }, + { &hf_stt_vlan, + { "VLAN", "stt.vlan", + FT_UINT16, BASE_HEX, NULL, 0x0, + NULL, HFILL, + }, + }, + { &hf_stt_pcp, + { "PCP", "stt.vlan.pcp", + FT_UINT16, BASE_DEC, VALS(pri_vals), STT_PCP_MASK, + NULL, HFILL, + }, + }, + { &hf_stt_v, + { "V flag", "stt.vlan.v", + FT_UINT16, BASE_DEC, NULL, STT_V_MASK, + NULL, HFILL, + }, + }, + { &hf_stt_vlan_id, + { "VLAN ID", "stt.vlan.id", + FT_UINT16, BASE_DEC, NULL, STT_VLANID_MASK, + NULL, HFILL, + }, + }, + { &hf_stt_context_id, + { "Context ID", "stt.context_id", + FT_UINT64, BASE_HEX, NULL, 0x0, + NULL, HFILL, + }, + }, + { &hf_stt_padding, + { "Padding", "stt.padding", + FT_UINT16, BASE_HEX, NULL, 0x0, + NULL, HFILL, + }, + }, + + /* Checksum validation fields */ + { &hf_stt_checksum, + { "Checksum", "stt.checksum", + FT_UINT16, BASE_HEX, NULL, 0x0, + "Details at: https://www.wireshark.org/docs/wsug_html_chunked/ChAdvChecksums.html", HFILL + }, + }, + { &hf_stt_checksum_status, + { "Checksum Status", "stt.checksum.status", + FT_UINT8, BASE_NONE, VALS(proto_checksum_vals), 0x0, + NULL, HFILL + }, + }, + + /* Segment reassembly information. */ + { &hf_segment_overlap, + { "Segment overlap", "stt.segment.overlap", + FT_BOOLEAN, BASE_NONE, NULL, 0x0, + "Segment overlaps with other segments", HFILL + }, + }, + { &hf_segment_overlap_conflict, + { "Conflicting data in segment overlap", "stt.segment.overlap.conflict", + FT_BOOLEAN, BASE_NONE, NULL, 0x0, + "Overlapping segments contained conflicting data", HFILL + }, + }, + { &hf_segment_multiple_tails, + { "Multiple tail segments found", "stt.segment.multipletails", + FT_BOOLEAN, BASE_NONE, NULL, 0x0, + "Several tails were found when reassembling the packet", HFILL + }, + }, + { &hf_segment_too_long_fragment, + { "Segment too long", "stt.segment.toolongfragment", + FT_BOOLEAN, BASE_NONE, NULL, 0x0, + "Segment contained data past end of the packet", HFILL + }, + }, + { &hf_segment_error, + { "Reassembling error", "stt.segment.error", + FT_FRAMENUM, BASE_NONE, NULL, 0x0, + "Reassembling error due to illegal segments", HFILL + }, + }, + { &hf_segment_count, + { "Segment count", "stt.segment.count", + FT_UINT32, BASE_DEC, NULL, 0x0, + NULL, HFILL + }, + }, + { &hf_segment, + { "STT Segment", "stt.segment", + FT_FRAMENUM, BASE_NONE, NULL, 0x0, + NULL, HFILL + }, + }, + { &hf_segments, + { "Reassembled STT Segments", "stt.segments", + FT_NONE, BASE_NONE, NULL, 0x0, + "STT Segments", HFILL + }, + }, + { &hf_reassembled_in, + { "Reassembled PDU in frame", "stt.reassembled_in", + FT_FRAMENUM, BASE_NONE, NULL, 0x0, + "The STT packet is reassembled in this frame", HFILL + }, + }, + { &hf_reassembled_length, + { "Reassembled STT length", "stt.reassembled.length", + FT_UINT32, BASE_DEC, NULL, 0x0, + "The total length of the reassembled payload", HFILL + }, + }, + }; + + /* Setup protocol subtree array */ + static gint *ett[] = { + &ett_stt, + &ett_stt_tcp_data, + &ett_stt_tcp_flags, + &ett_stt_flgs, + &ett_stt_vlan, + &ett_segment, + &ett_segments + }; + + static ei_register_info ei[] = { + { &ei_stt_checksum_bad, + { "stt.checksum_bad.expert", PI_CHECKSUM, + PI_ERROR, "Bad checksum", EXPFILL + } + }, + { &ei_stt_data_offset_bad, + { "stt.data_offset_bad.expert", PI_PROTOCOL, + PI_WARN, "TCP Data Offset should be 20 bytes", EXPFILL + } + }, + { &ei_stt_ver_unknown, + { "stt.version_unknown.expert", PI_PROTOCOL, + PI_WARN, "Unknown version", EXPFILL + } + }, + { &ei_stt_l4_offset, + { "stt.l4offset_bad.expert", PI_PROTOCOL, + PI_WARN, "Bad L4 Offset", EXPFILL + } + }, + { &ei_stt_mss, + { "stt.mss_bad.expert", PI_PROTOCOL, + PI_WARN, "Bad MSS", EXPFILL + } + }, + }; + + /* Register the protocol name and description */ + proto_stt = proto_register_protocol("Stateless Transport Tunneling", + "STT", "stt"); + + expert_stt = expert_register_protocol(proto_stt); + expert_register_field_array(expert_stt, ei, array_length(ei)); + + /* Required function calls to register the header fields and + subtrees used */ + proto_register_field_array(proto_stt, hf, array_length(hf)); + proto_register_subtree_array(ett, array_length(ett)); + + stt_prefs = prefs_register_protocol(proto_stt, NULL); + prefs_register_bool_preference(stt_prefs, "reassemble", + "Reassemble segmented STT packets", + "Reassembles greater than MTU sized STT packets broken into segments on transmit", + &pref_reassemble); + prefs_register_bool_preference(stt_prefs, "check_checksum", + "Validate the STT checksum if possible", + "Whether to validate the STT checksum or not.", + &pref_check_checksum); + + reassembly_table_register(&stt_reassembly_table, + &addresses_reassembly_table_functions); +} + +void +proto_reg_handoff_stt(void) +{ + /* + * The I-D doesn't explicity indicate that the FCS isn't present + * in the tunneled Ethernet frames, but it is missing from the + * captures attached to bug 10282. + */ + eth_handle = find_dissector_add_dependency("eth_withoutfcs", proto_stt); + + heur_dissector_add("ip", dissect_stt_heur, "Stateless Transport Tunneling over IP", "stt_ip", proto_stt, HEURISTIC_ENABLE); +} + +/* + * Editor modelines - https://www.wireshark.org/tools/modelines.html + * + * Local variables: + * c-basic-offset: 4 + * tab-width: 8 + * indent-tabs-mode: nil + * End: + * + * vi: set shiftwidth=4 tabstop=8 expandtab: + * :indentSize=4:tabSize=8:noTabs=true: + */ -- cgit v1.2.3