packet-dccp.h

/* packet-dccp.h
 * Definitions for Datagram Congestion Control Protocol, "DCCP" dissection:
 * it should conform to RFC 4340
 *
 * Copyright 2005 _FF_
 *
 * Francesco Fondelli <francesco dot fondelli, gmail dot com>
 *
 * Copyright 2020-2021 by Thomas Dreibholz <dreibh [AT] simula.no>
 *
 * template taken from packet-udp.c
 *
 * Wireshark - Network traffic analyzer
 * By Gerald Combs <gerald@wireshark.org>
 * Copyright 1998 Gerald Combs
 *
 * SPDX-License-Identifier: GPL-2.0-or-later
 */
 
#ifndef __PACKET_DCCP_H__
#define __PACKET_DCCP_H__
 
#ifdef __cplusplus
extern "C" {
#endif /* __cplusplus */
 
 
/*
 * DCCP Service Codes.
 * From https://www.iana.org/assignments/service-codes/service-codes.xhtml
 * as of 2021-02-19
 *
 * Please do not put non-IANA-registered service codes here.  Put them in the
 * dissector using them instead (and consider registering them!).
 */
#define NOT_SPECIFIED_SERVICE_CODE            0
#define LTP_SERVICE_CODE                7107696
#define DISC_SERVICE_CODE            1145656131
#define RTCP_SERVICE_CODE            1381253968
#define RTPA_SERVICE_CODE            1381257281
#define RTPO_SERVICE_CODE            1381257295
#define RTPT_SERVICE_CODE            1381257300
#define RTPV_SERVICE_CODE            1381257302
#define SYLG_SERVICE_CODE            1398361159
#define BUNDLES_SERVICE_CODE         1685351985
#define NPMP_SERVICE_CODE            1852861808
#define RESERVED_SERVICE_CODE        4294967295
 
 
 
/* DCCP structs and definitions */
typedef struct _e_dccphdr {
    uint16_t sport;
    uint16_t dport;
    uint8_t data_offset;
    uint8_t cscov;         /* 4 bits */
    uint8_t ccval;         /* 4 bits */
    uint16_t checksum;
    uint8_t reserved1;     /* 3 bits */
    uint8_t type;          /* 4 bits */
    bool x;           /* 1 bits */
    uint8_t reserved2;     /* if x == 1 */
    uint64_t seq;          /* 48 or 24 bits sequence number */
 
    uint16_t ack_reserved; /*
                           * for all defined packet types except DCCP-Request
                           * and DCCP-Data
                           */
    uint64_t ack;           /* 48 or 24 bits acknowledgement sequence number */
 
    uint32_t service_code;
    uint8_t reset_code;
    uint8_t data1;
    uint8_t data2;
    uint8_t data3;
 
    uint32_t stream; /* this stream index field is included to help differentiate when address/port pairs are reused */
 
    address ip_src;
    address ip_dst;
} e_dccphdr;
 
typedef struct _dccp_flow_t {
    uint8_t static_flags;   /* flags */
    uint64_t base_seq;       /* base seq number (used by relative sequence numbers) */
    uint32_t base_frame;     /* frame of the Request or Response that set base_seq */
} dccp_flow_t;
 
struct dccp_analysis {
    /* These two structs are managed based on comparing the source
     * and destination addresses and, if they're equal, comparing
     * the source and destination ports.
     *
     * If the source is greater than the destination, then stuff
     * sent from src is in flow1.
     *
     * If the source is less than the destination, then stuff
     * sent from src is in flow2.
     *
     * XXX - if the addresses and ports are equal, we don't guarantee
     * the behavior.
     */
    dccp_flow_t flow1;
    dccp_flow_t flow2;
 
    /* These pointers are set by get_dccp_conversation_data()
     * fwd point in the same direction as the current packet
     * and rev in the reverse direction
     */
    dccp_flow_t *fwd;
    dccp_flow_t *rev;
 
    /* Keep track of dccp stream numbers instead of using the conversation
     * index (as how it was done before). This prevents gaps in the
     * stream index numbering
     */
    uint32_t        stream;
 
    /* Remember the timestamp of the first frame seen in this dccp
     * conversation to be able to calculate a relative time compared
     * to the start of this conversation
     */
    nstime_t    ts_first;
 
    /* Remember the timestamp of the frame that was last seen in this
     * dccp conversation to be able to calculate a delta time compared
     * to previous frame in this conversation
     */
    nstime_t    ts_prev;
};
 
#ifdef __cplusplus
}
#endif /* __cplusplus */
 
#endif /* __PACKET_DCCP_H__ */
 
/*
 * 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:
 */