/* packet-fbzero.c

 * Routines for Zero Protocol dissection

 * Copyright 2016-2017, Alexis La Goutte <alexis.lagoutte at gmail dot com>

 *

 * Wireshark - Network traffic analyzer

 * By Gerald Combs <gerald@wireshark.org>

 * Copyright 1998 Gerald Combs

 *

 * SPDX-License-Identifier: GPL-2.0-or-later

 */

/*

 * Zero Protocol coming from Facebook and used the same framing like QUIC

 * (tag-map value) but based on TCP

 *

 * See

 *

 *    https://engineering.fb.com/networking-traffic/building-zero-protocol-for-fast-secure-mobile-connections/

 *

 * for some (not much!) information on it.

 *

 * It was reverse engineered based off of QUIC dissector functionality

 */

#include "config.h"

#include <epan/packet.h>

#include <epan/tfs.h>

#include <epan/expert.h>

#include <epan/conversation.h>

void proto_register_fb_zero(void);

void proto_reg_handoff_fb_zero(void);

static int proto_fb_zero;

static dissector_handle_t fb_zero_handle;

static int hf_fb_zero_puflags;

static int hf_fb_zero_puflags_vrsn;

static int hf_fb_zero_puflags_unknown;

static int hf_fb_zero_version;

static int hf_fb_zero_length;

static int hf_fb_zero_tag;

static int hf_fb_zero_tags;

static int hf_fb_zero_tag_number;

static int hf_fb_zero_tag_value;

static int hf_fb_zero_tag_type;

static int hf_fb_zero_tag_offset_end;

static int hf_fb_zero_tag_length;

static int hf_fb_zero_tag_sni;

static int hf_fb_zero_tag_vers;

static int hf_fb_zero_tag_sno;

static int hf_fb_zero_tag_aead;

static int hf_fb_zero_tag_scid;

static int hf_fb_zero_tag_time;

static int hf_fb_zero_tag_alpn;

static int hf_fb_zero_tag_pubs;

static int hf_fb_zero_tag_kexs;

static int hf_fb_zero_tag_nonc;

static int hf_fb_zero_tag_unknown;

static int hf_fb_zero_padding;

static int hf_fb_zero_payload;

static int hf_fb_zero_unknown;

static int ett_fb_zero;

static int ett_fb_zero_puflags;

static int ett_fb_zero_prflags;

static int ett_fb_zero_ft;

static int ett_fb_zero_ftflags;

static int ett_fb_zero_tag_value;

static expert_field ei_fb_zero_tag_undecoded;

static expert_field ei_fb_zero_tag_offset_end_invalid;

static expert_field ei_fb_zero_length_invalid;

#define FBZERO_MIN_LENGTH 3

#define VERSION_QTV 0x515456

/**************************************************************************/

/*                      Public Flags                                      */

/**************************************************************************/

#define PUFLAGS_VRSN    0x01

#define PUFLAGS_UNKN    0xFE

/**************************************************************************/

/*                      Message tag                                       */

/**************************************************************************/

#define MTAG_CHLO 0x43484C4F

#define MTAG_SNOM 0x534E4F4D

#define MTAG_SHLO 0x53484C4F

#define MTAG_REJ  0x52454A00

#define MTAG_PRST 0x50525354

static const value_string message_tag_vals[] = {

    { MTAG_CHLO, "Client Hello" },

    { MTAG_SNOM, "Server NOM??" },

    { MTAG_SHLO, "Server Hello" },

    { MTAG_REJ, "Rejection" },

    { MTAG_PRST, "Public Reset" },

    { 0, NULL }

};

/**************************************************************************/

/*                      Tag                                               */

/**************************************************************************/

#define TAG_SNI  0x534E4900

#define TAG_VERS 0x56455253

#define TAG_SNO  0x534E4F00

#define TAG_AEAD 0x41454144

#define TAG_SCID 0x53434944

#define TAG_TIME 0x54494d45

#define TAG_ALPN 0x414C504E

#define TAG_PUBS 0x50554253

#define TAG_KEXS 0x4B455853

#define TAG_NONC 0x4E4F4E43

static const value_string tag_vals[] = {

    { TAG_SNI, "Server Name Indication" },

    { TAG_VERS, "Version" },

    { TAG_SNO, "Server nonce" },

    { TAG_AEAD, "Authenticated encryption algorithms" },

    { TAG_SCID, "Server config ID" },

    { TAG_TIME, "Time" },

    { TAG_ALPN, "ALPN" },

    { TAG_PUBS, "Public value" },

    { TAG_KEXS, "Key exchange algorithms" },

    { TAG_NONC, "Client Nonce" },

    { 0, NULL }

};

/**************************************************************************/

/*                      AEAD Tag                                          */

/**************************************************************************/

#define AEAD_AESG  0x41455347

#define AEAD_S20P  0x53323050

#define AEAD_CC12  0x43433132

static const value_string tag_aead_vals[] = {

    { AEAD_AESG, "AES-GCM with a 12-byte tag and IV" },

    { AEAD_S20P, "Salsa20 with Poly1305" },

    { AEAD_CC12, "ChaCha12 with Poly1305" },

    { 0, NULL }

};

/**************************************************************************/

/*                      KEXS Tag                                          */

/**************************************************************************/

#define KEXS_C255  0x43323535

#define KEXS_P256  0x50323536

static const value_string tag_kexs_vals[] = {

    { KEXS_C255, "Curve25519" },

    { KEXS_P256, "P-256" },

    { 0, NULL }

};

static uint32_t

dissect_fb_zero_tag(tvbuff_t *tvb, packet_info *pinfo, proto_tree *fb_zero_tree, unsigned offset, uint32_t tag_number){

    uint32_t tag_offset_start = offset + tag_number*4*2;

    uint32_t tag_offset = 0, total_tag_len = 0;

    int32_t tag_len = 0;

    bool tag_offset_valid = true;

    while(tag_number){

        proto_tree *tag_tree;

        proto_item *ti_tag, *ti_type, *ti_offset_len, *ti_len;

        uint32_t offset_end, tag;

        const uint8_t* tag_str;

        /*

         * This item covers the tag type and end offset; the tag values

         * are in a separate region following all the type/end offset

         * pairs.

         */

        ti_tag = proto_tree_add_item(fb_zero_tree, hf_fb_zero_tags, tvb, offset, 4*2, ENC_NA);

        tag_tree = proto_item_add_subtree(ti_tag, ett_fb_zero_tag_value);

        ti_type = proto_tree_add_item_ret_string(tag_tree, hf_fb_zero_tag_type, tvb, offset, 4, ENC_ASCII|ENC_NA, pinfo->pool, &tag_str);

        tag = tvb_get_ntohl(tvb, offset);

        proto_item_append_text(ti_type, " (%s)", val_to_str_const(tag, tag_vals, "Unknown"));

        proto_item_append_text(ti_tag, ": %s (%s)", tag_str, val_to_str_const(tag, tag_vals, "Unknown"));

        offset += 4;

        ti_offset_len = proto_tree_add_item_ret_uint(tag_tree, hf_fb_zero_tag_offset_end, tvb, offset, 4, ENC_LITTLE_ENDIAN, &offset_end);

        if(offset_end < tag_offset){

            expert_add_info_format(pinfo, ti_offset_len, &ei_fb_zero_tag_offset_end_invalid,

                                   "Invalid tag end offset %u < %u",

                                   offset_end, tag_offset);

            /*

             * We can continue to show the tag type, end offset, and length,

             * but we can no longer show the values, or subsequent length

             * values, as the end offset in the tag value region is bogus.

             */

            tag_offset_valid = false;

        } else {

            tag_len = offset_end - tag_offset;

            if(!tvb_bytes_exist(tvb, tag_offset_start + tag_offset, tag_len)){

                expert_add_info_format(pinfo, ti_offset_len, &ei_fb_zero_tag_offset_end_invalid,

                                       "Invalid tag end offset %u past end of packet",

                                       offset_end);

                /*

                 * We can continue to show the tag type, end offset,

                 * and length, but we can no longer show the values,

                 * as the end offset in the tag value region is bogus.

                 *

                 * We don't just throw an exception here, because we

                 * want to show all the tag type and end offset values.

                 */

                tag_offset_valid = false;

            }

            total_tag_len += tag_len;

            ti_len = proto_tree_add_uint(tag_tree, hf_fb_zero_tag_length, tvb, offset, 4, tag_len);

            proto_item_append_text(ti_tag, " (l=%u)", tag_len);

            proto_item_set_generated(ti_len);

        }

        offset += 4;

        if(tag_offset_valid){

            proto_tree_add_item(tag_tree, hf_fb_zero_tag_value, tvb, tag_offset_start + tag_offset, tag_len, ENC_NA);

        }

        switch(tag){

            case TAG_SNI:

                if(tag_offset_valid){

                    proto_tree_add_item_ret_string(tag_tree, hf_fb_zero_tag_sni, tvb, tag_offset_start + tag_offset, tag_len, ENC_ASCII|ENC_NA, pinfo->pool, &tag_str);

                    proto_item_append_text(ti_tag, ": %s", tag_str);

                    tag_offset += tag_len;

                }

                break;

            case TAG_VERS:

                if(tag_offset_valid){

                    if(tag_len != 4){

                        expert_add_info_format(pinfo, fb_zero_tree, &ei_fb_zero_length_invalid,

                                               "Invalid tag length: %u, should be 4", tag_len);

                        tag_offset += tag_len;

                        break;

                    }

                    proto_tree_add_item_ret_string(tag_tree, hf_fb_zero_tag_vers, tvb, tag_offset_start + tag_offset, 4, ENC_ASCII|ENC_NA, pinfo->pool, &tag_str);

                    proto_item_append_text(ti_tag, ": %s", tag_str);

                    tag_offset += 4;

                }

            break;

            case TAG_SNO:

                if(tag_offset_valid){

                    proto_tree_add_item(tag_tree, hf_fb_zero_tag_sno, tvb, tag_offset_start + tag_offset, tag_len, ENC_NA);

                    tag_offset += tag_len;

                }

            break;

            case TAG_AEAD:

                if(tag_offset_valid){

                    while(offset_end - tag_offset >= 4){

                        proto_tree *ti_aead;

                        ti_aead = proto_tree_add_item(tag_tree, hf_fb_zero_tag_aead, tvb, tag_offset_start + tag_offset, 4, ENC_ASCII);

                        proto_item_append_text(ti_aead, " (%s)", val_to_str_const(tvb_get_ntohl(tvb, tag_offset_start + tag_offset), tag_aead_vals, "Unknown"));

                        proto_item_append_text(ti_tag, ", %s", val_to_str_const(tvb_get_ntohl(tvb, tag_offset_start + tag_offset), tag_aead_vals, "Unknown"));

                        tag_offset += 4;

                    }

                    if(offset_end - tag_offset > 0){

                        expert_add_info_format(pinfo, fb_zero_tree, &ei_fb_zero_length_invalid,

                                               "Invalid tag length: %u, should be a multiple of 4", tag_len);

                        tag_offset = offset_end;

                    }

                }

            break;

            case TAG_SCID:

                if(tag_offset_valid){

                    proto_tree_add_item(tag_tree, hf_fb_zero_tag_scid, tvb, tag_offset_start + tag_offset, tag_len, ENC_NA);

                    tag_offset += tag_len;

                }

            break;

            case TAG_TIME:

                if(tag_offset_valid){

                    if(tag_len != 4){

                        expert_add_info_format(pinfo, fb_zero_tree, &ei_fb_zero_length_invalid,

                                               "Invalid tag length: %u, should be 4", tag_len);

                        tag_offset += tag_len;

                        break;

                    }

                    proto_tree_add_item(tag_tree, hf_fb_zero_tag_time, tvb, tag_offset_start + tag_offset, 4, ENC_LITTLE_ENDIAN);

                    proto_item_append_text(ti_tag, ": %u", tvb_get_letohl(tvb, tag_offset_start + tag_offset));

                    tag_offset += 4;

                }

            break;

            case TAG_ALPN:

                if(tag_offset_valid){

                    if(tag_len != 4){

                        expert_add_info_format(pinfo, fb_zero_tree, &ei_fb_zero_length_invalid,

                                               "Invalid tag length: %u, should be 4", tag_len);

                        tag_offset += tag_len;

                        break;

                    }

                    proto_tree_add_item_ret_string(tag_tree, hf_fb_zero_tag_alpn, tvb, tag_offset_start + tag_offset, 4, ENC_ASCII|ENC_NA, pinfo->pool, &tag_str);

                    proto_item_append_text(ti_tag, ": %s", tag_str);

                    tag_offset += 4;

                }

            break;

            case TAG_PUBS:

                if(tag_offset_valid){

                    /*TODO FIX: 24 Length + Pubs key?.. ! */

                    if(tag_len < 2){

                        expert_add_info_format(pinfo, fb_zero_tree, &ei_fb_zero_length_invalid,

                                               "Invalid tag length: %u, should be >= 2", tag_len);

                        tag_offset += tag_len;

                        break;

                    }

                    proto_tree_add_item(tag_tree, hf_fb_zero_tag_pubs, tvb, tag_offset_start + tag_offset, 2, ENC_LITTLE_ENDIAN);

                    tag_offset += 2;

                    while(offset_end - tag_offset >= 3){

                        proto_tree_add_item(tag_tree, hf_fb_zero_tag_pubs, tvb, tag_offset_start + tag_offset, 3, ENC_LITTLE_ENDIAN);

                        tag_offset += 3;

                    }

                    if(offset_end - tag_offset > 0){

                        expert_add_info_format(pinfo, fb_zero_tree, &ei_fb_zero_length_invalid,

                                               "Invalid tag length: %u, should be a multiple of 3", tag_len);

                        tag_offset = offset_end;

                    }

                }

            break;

            case TAG_KEXS:

                if(tag_offset_valid){

                    while(offset_end - tag_offset >= 4){

                        proto_tree *ti_kexs;

                        ti_kexs = proto_tree_add_item(tag_tree, hf_fb_zero_tag_kexs, tvb, tag_offset_start + tag_offset, 4, ENC_ASCII);

                        proto_item_append_text(ti_kexs, " (%s)", val_to_str_const(tvb_get_ntohl(tvb, tag_offset_start + tag_offset), tag_kexs_vals, "Unknown"));

                        proto_item_append_text(ti_tag, ", %s", val_to_str_const(tvb_get_ntohl(tvb, tag_offset_start + tag_offset), tag_kexs_vals, "Unknown"));

                        tag_offset += 4;

                    }

                    if(offset_end - tag_offset > 0){

                        expert_add_info_format(pinfo, fb_zero_tree, &ei_fb_zero_length_invalid,

                                               "Invalid tag length: %u, should be a multiple of 4", tag_len);

                        tag_offset = offset_end;

                    }

                }

            break;

            case TAG_NONC:

                if(tag_offset_valid){

                    /*TODO: Enhance display: 32 bytes consisting of 4 bytes of timestamp (big-endian, UNIX epoch seconds), 8 bytes of server orbit and 20 bytes of random data. */

                    if(tag_len != 32){

                        expert_add_info_format(pinfo, fb_zero_tree, &ei_fb_zero_length_invalid,

                                               "Invalid tag length: %u, should be 32", tag_len);

                        tag_offset += tag_len;

                        break;

                    }

                    proto_tree_add_item(tag_tree, hf_fb_zero_tag_nonc, tvb, tag_offset_start + tag_offset, 32, ENC_NA);

                    tag_offset += 32;

                }

            break;

            default:

                expert_add_info_format(pinfo, ti_tag, &ei_fb_zero_tag_undecoded,

                                 "Dissector for FB Zero Tag"

                                 " %s (%s) code not implemented, Contact"

                                 " Wireshark developers if you want this supported",

                                 tvb_get_string_enc(pinfo->pool, tvb, offset-8, 4, ENC_ASCII|ENC_NA), val_to_str_const(tag, tag_vals, "Unknown"));

                if(tag_offset_valid){

                    proto_tree_add_item(tag_tree, hf_fb_zero_tag_unknown, tvb, tag_offset_start + tag_offset, tag_len, ENC_NA);

                    tag_offset += tag_len;

                }

                break;

        }

        tag_number--;

    }

    /* XXX - can this still occur? */

    if (offset + total_tag_len <= offset) {

        expert_add_info_format(pinfo, fb_zero_tree, &ei_fb_zero_length_invalid,

                         "Invalid total tag length: %u", total_tag_len);

        return offset + tvb_reported_length_remaining(tvb, offset);

    }

    return offset + total_tag_len;

}

static int

dissect_fb_zero_unencrypt(tvbuff_t *tvb, packet_info *pinfo, proto_tree *fb_zero_tree, unsigned offset, uint8_t len_pkn _U_){

    while(tvb_reported_length_remaining(tvb, offset) > 0){

        proto_item *ti;

        uint32_t message_tag, tag_number, length;

        const uint8_t* message_tag_str;

        proto_tree_add_item(fb_zero_tree, hf_fb_zero_unknown, tvb, offset, 1, ENC_NA);

        offset += 1;

        /*

         * XXX: in theory, a tagged message could be split between

         * TCP segments - even the *header containing the length*

         * could be split - but, from the sequence described in the

         * Facebook blog post, that's probably unlikely in practice.

         */

        proto_tree_add_item_ret_uint(fb_zero_tree, hf_fb_zero_length, tvb, offset, 4, ENC_LITTLE_ENDIAN, &length);

        offset += 4;

        message_tag = tvb_get_ntohl(tvb, offset);

        /* check if it is a known message_tag (CHLO, SNOM...) */

        if(try_val_to_str(message_tag, message_tag_vals)){

            ti = proto_tree_add_item_ret_string(fb_zero_tree, hf_fb_zero_tag, tvb, offset, 4, ENC_ASCII|ENC_NA, pinfo->pool, &message_tag_str);

            proto_item_append_text(ti, ", Type: %s (%s)", message_tag_str,

                                   val_to_str_const(message_tag, message_tag_vals, "Unknown Tag"));

            col_set_str(pinfo->cinfo, COL_INFO, val_to_str_const(message_tag, message_tag_vals, "Unknown"));

            offset += 4;

            proto_tree_add_item(fb_zero_tree, hf_fb_zero_tag_number, tvb, offset, 2, ENC_LITTLE_ENDIAN);

            tag_number = tvb_get_letohs(tvb, offset);

            offset += 2;

            proto_tree_add_item(fb_zero_tree, hf_fb_zero_padding, tvb, offset, 2, ENC_NA);

            offset += 2;

            offset = dissect_fb_zero_tag(tvb, pinfo, fb_zero_tree, offset, tag_number);

        } else {

            proto_tree_add_item(fb_zero_tree, hf_fb_zero_unknown, tvb, offset, length, ENC_NA);

            offset += length;

        }

    }

    return offset;

}

static int

dissect_fb_zero_common(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree,

        void *data _U_)

{

    proto_item *ti, *ti_puflags;

    proto_tree *fb_zero_tree, *puflags_tree;

    unsigned offset = 0;

    uint8_t puflags;

    uint32_t message_tag, version;

    if (tvb_captured_length(tvb) < FBZERO_MIN_LENGTH)

        return 0;

    col_set_str(pinfo->cinfo, COL_PROTOCOL, "FB_ZERO");

    ti = proto_tree_add_item(tree, proto_fb_zero, tvb, 0, -1, ENC_NA);

    fb_zero_tree = proto_item_add_subtree(ti, ett_fb_zero);

    /* Public Flags */

    ti_puflags = proto_tree_add_item(fb_zero_tree, hf_fb_zero_puflags, tvb, offset, 1, ENC_LITTLE_ENDIAN);

    puflags_tree = proto_item_add_subtree(ti_puflags, ett_fb_zero_puflags);

    proto_tree_add_item(puflags_tree, hf_fb_zero_puflags_vrsn, tvb, offset, 1, ENC_NA);

    proto_tree_add_item(puflags_tree, hf_fb_zero_puflags_unknown, tvb, offset, 1, ENC_LITTLE_ENDIAN);

    puflags = tvb_get_uint8(tvb, offset);

    offset += 1;

    if(puflags & PUFLAGS_VRSN){

        version = tvb_get_ntoh24(tvb, offset);

        if(version == VERSION_QTV){

            proto_tree_add_item(fb_zero_tree, hf_fb_zero_version, tvb, offset, 3, ENC_ASCII);

            offset += 3;

        }

    }

    /* Unencrypt Message (Handshake or Connection Close...) */

    message_tag = tvb_get_ntohl(tvb, offset+5);

    if (message_tag == MTAG_CHLO || message_tag == MTAG_SNOM) {

        offset = dissect_fb_zero_unencrypt(tvb, pinfo, fb_zero_tree, offset, 1);

    }else {     /* Payload... (encrypted... TODO FIX !) */

        col_set_str(pinfo->cinfo, COL_INFO, "Payload (Encrypted)");

        proto_tree_add_item(fb_zero_tree, hf_fb_zero_payload, tvb, offset, -1, ENC_NA);

    }

    return offset;

}

static int

dissect_fb_zero(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree,

              void *data _U_)

{

    return dissect_fb_zero_common(tvb, pinfo, tree, NULL);

}

static bool dissect_fb_zero_heur(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data)

{

    conversation_t *conversation = NULL;

    int offset = 0;

    uint32_t version, length, message_tag;

    /* Verify packet size (Flag (1 byte) + Version (3bytes) + Flag (1 byte) + length (4 bytes) + Tag (4 bytes)) */

    if (tvb_captured_length(tvb) < 13)

    {

        return false;

    }

    /* Flag */

    offset += 1;

    /* Version */

    version = tvb_get_ntoh24(tvb, offset);

    offset += 3;

    /* Flag */

    offset += 1;

    /* length */

    length = tvb_get_letohl(tvb, offset);

    offset += 4;

    /* (message) tag */

    message_tag = tvb_get_ntohl(tvb, offset);

    if (version == VERSION_QTV && length <= tvb_reported_length(tvb) && (message_tag == MTAG_CHLO || message_tag == MTAG_SNOM)) {

        conversation = find_or_create_conversation(pinfo);

        conversation_set_dissector(conversation, fb_zero_handle);

        dissect_fb_zero(tvb, pinfo, tree, data);

        return true;

    }

    return false;

}

void

proto_register_fb_zero(void)

{

    static hf_register_info hf[] = {

        { &hf_fb_zero_puflags,

            { "Public Flags", "fb_zero.puflags",

              FT_UINT8, BASE_HEX, NULL, 0x0,

              "Specifying per-packet public flags", HFILL }

        },

        { &hf_fb_zero_puflags_vrsn,

            { "Version", "fb_zero.puflags.version",

              FT_BOOLEAN, 8, TFS(&tfs_yes_no), PUFLAGS_VRSN,

              "Signifies that this packet also contains the version of the FB Zero protocol", HFILL }

        },

        { &hf_fb_zero_puflags_unknown,

            { "Unknown", "fb_zero.puflags.unknown",

              FT_UINT8, BASE_HEX, NULL, PUFLAGS_UNKN,

              NULL, HFILL }

        },

        { &hf_fb_zero_version,

            { "Version", "fb_zero.version",

              FT_STRING, BASE_NONE, NULL, 0x0,

              "32 bit opaque tag that represents the version of the ZB Zero (Always QTV)", HFILL }

        },

        { &hf_fb_zero_length,

            { "Length", "fb_zero.length",

              FT_UINT32, BASE_DEC, NULL, 0x0,

              NULL, HFILL }

        },

        { &hf_fb_zero_tag,

            { "Tag", "fb_zero.tag",

              FT_STRING, BASE_NONE, NULL, 0x0,

              NULL, HFILL }

        },

        { &hf_fb_zero_tag_number,

            { "Tag Number", "fb_zero.tag_number",

              FT_UINT16, BASE_DEC, NULL, 0x0,

              NULL, HFILL }

        },

        { &hf_fb_zero_tags,

            { "Tag/value", "fb_zero.tags",

              FT_NONE, BASE_NONE, NULL, 0x0,

              NULL, HFILL }

        },

        { &hf_fb_zero_tag_type,

            { "Tag Type", "fb_zero.tag_type",

              FT_STRING, BASE_NONE, NULL, 0x0,

              NULL, HFILL }

        },

        { &hf_fb_zero_tag_offset_end,

            { "Tag offset end", "fb_zero.tag_offset_end",

              FT_UINT32, BASE_DEC, NULL, 0x0,

              NULL, HFILL }

        },

        { &hf_fb_zero_tag_length,

            { "Tag length", "fb_zero.tag_offset_length",

              FT_UINT32, BASE_DEC, NULL, 0x0,

              NULL, HFILL }

        },

        { &hf_fb_zero_tag_value,

            { "Tag/value", "fb_zero.tag_value",

              FT_BYTES, BASE_NONE, NULL, 0x0,

              NULL, HFILL }

        },

        { &hf_fb_zero_tag_sni,

            { "Server Name Indication", "fb_zero.tag.sni",

              FT_STRING, BASE_NONE, NULL, 0x0,

              "The fully qualified DNS name of the server, canonicalised to lowercase with no trailing period", HFILL }

        },

        { &hf_fb_zero_tag_vers,

            { "Version", "fb_zero.tag.version",

              FT_STRING, BASE_NONE, NULL, 0x0,

              "Version of FB Zero supported", HFILL }

        },

        { &hf_fb_zero_tag_sno,

            { "Server nonce", "fb_zero.tag.sno",

              FT_BYTES, BASE_NONE, NULL, 0x0,

              NULL, HFILL }

        },

        { &hf_fb_zero_tag_aead,

            { "Authenticated encryption algorithms", "fb_zero.tag.aead",

              FT_STRING, BASE_NONE, NULL, 0x0,

              "A list of tags, in preference order, specifying the AEAD primitives supported by the server", HFILL }

        },

        { &hf_fb_zero_tag_scid,

            { "Server Config ID", "fb_zero.tag.scid",

              FT_BYTES, BASE_NONE, NULL, 0x0,

              "An opaque, 16-byte identifier for this server config", HFILL }

        },

        { &hf_fb_zero_tag_time,

            { "Time", "fb_zero.tag.time",

              FT_UINT32, BASE_DEC, NULL, 0x0,

              NULL, HFILL }

        },

        { &hf_fb_zero_tag_alpn,

            { "ALPN", "fb_zero.tag.alpn",

              FT_STRING, BASE_NONE, NULL, 0x0,

              "Application-Layer Protocol Negotiation supported", HFILL }

        },

        { &hf_fb_zero_tag_pubs,

            { "Public value", "fb_zero.tag.pubs",

              FT_UINT24, BASE_DEC_HEX, NULL, 0x0,

              "A list of public values, 24-bit, little-endian length prefixed", HFILL }

        },

        { &hf_fb_zero_tag_kexs,

            { "Key exchange algorithms", "fb_zero.tag.kexs",

              FT_STRING, BASE_NONE, NULL, 0x0,

              "A list of tags, in preference order, specifying the key exchange algorithms that the server supports", HFILL }

        },

        { &hf_fb_zero_tag_nonc,

            { "Client nonce", "fb_zero.tag.nonc",

              FT_BYTES, BASE_NONE, NULL, 0x0,

              "32 bytes consisting of 4 bytes of timestamp (big-endian, UNIX epoch seconds), 8 bytes of server orbit and 20 bytes of random data", HFILL }

        },

        { &hf_fb_zero_tag_unknown,

            { "Unknown tag", "fb_zero.tag.unknown",

              FT_BYTES, BASE_NONE, NULL, 0x0,

              NULL, HFILL }

        },

        { &hf_fb_zero_padding,

            { "Padding", "fb_zero.padding",

              FT_BYTES, BASE_NONE, NULL, 0x0,

              NULL, HFILL }

        },

        { &hf_fb_zero_payload,

            { "Payload", "fb_zero.payload",

              FT_BYTES, BASE_NONE, NULL, 0x0,

              "Fb Zero Payload..", HFILL }

        },

        { &hf_fb_zero_unknown,

            { "Unknown", "fb_zero.unknown",

              FT_BYTES, BASE_NONE, NULL, 0x0,

              "Unknown Data", HFILL }

        },

    };

    static int *ett[] = {

        &ett_fb_zero,

        &ett_fb_zero_puflags,

        &ett_fb_zero_prflags,

        &ett_fb_zero_ft,

        &ett_fb_zero_ftflags,

        &ett_fb_zero_tag_value

    };

    static ei_register_info ei[] = {

        { &ei_fb_zero_tag_undecoded, { "fb_zero.tag.undecoded", PI_UNDECODED, PI_NOTE, "Dissector for FB Zero Tag code not implemented, Contact Wireshark developers if you want this supported", EXPFILL }},

        { &ei_fb_zero_tag_offset_end_invalid, { "fb_zero.offset_end.invalid", PI_PROTOCOL, PI_ERROR, "Invalid tag end offset", EXPFILL }},

        { &ei_fb_zero_length_invalid, { "fb_zero.length.invalid", PI_PROTOCOL, PI_WARN, "Invalid length", EXPFILL }},

    };

    expert_module_t *expert_fb_zero;

    proto_fb_zero = proto_register_protocol("(Facebook) Zero Protocol", "FBZERO", "fb_zero");

    fb_zero_handle = register_dissector("fb_zero", dissect_fb_zero, proto_fb_zero);

    proto_register_field_array(proto_fb_zero, hf, array_length(hf));

    proto_register_subtree_array(ett, array_length(ett));

    expert_fb_zero = expert_register_protocol(proto_fb_zero);

    expert_register_field_array(expert_fb_zero, ei, array_length(ei));

}

void

proto_reg_handoff_fb_zero(void)

{

    heur_dissector_add("tcp", dissect_fb_zero_heur, "FBZero (QUIC) over TCP", "fb_zero", proto_fb_zero, 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:

 */