epan/dissectors/packet-dccp.h

   1 /* packet-dccp.h
   2  * Definitions for Datagram Congestion Control Protocol, "DCCP" dissection:
   3  * it should conform to RFC 4340
   4  *
   5  * Copyright 2005 _FF_
   6  *
   7  * Francesco Fondelli <francesco dot fondelli, gmail dot com>
   8  *
   9  * Copyright 2020-2021 by Thomas Dreibholz <dreibh [AT] simula.no>
  10  *
  11  * template taken from packet-udp.c
  12  *
  13  * Wireshark - Network traffic analyzer
  14  * By Gerald Combs <gerald@wireshark.org>
  15  * Copyright 1998 Gerald Combs
  16  *
  17  * SPDX-License-Identifier: GPL-2.0-or-later
  18  */
  19
  20 #ifndef __PACKET_DCCP_H__
  21 #define __PACKET_DCCP_H__
  22
  23 #ifdef __cplusplus
  24 extern "C" {
  25 #endif /* __cplusplus */
  26
  27 /* DCCP structs and definitions */
  28 typedef struct _e_dccphdr {
  29     uint16_t sport;
  30     uint16_t dport;
  31     uint8_t data_offset;
  32     uint8_t cscov;         /* 4 bits */
  33     uint8_t ccval;         /* 4 bits */
  34     uint16_t checksum;
  35     uint8_t reserved1;     /* 3 bits */
  36     uint8_t type;          /* 4 bits */
  37     bool x;           /* 1 bits */
  38     uint8_t reserved2;     /* if x == 1 */
  39     uint64_t seq;          /* 48 or 24 bits sequence number */
  40
  41     uint16_t ack_reserved; /*
  42                            * for all defined packet types except DCCP-Request
  43                            * and DCCP-Data
  44                            */
  45     uint64_t ack;           /* 48 or 24 bits acknowledgement sequence number */
  46
  47     uint32_t service_code;
  48     uint8_t reset_code;
  49     uint8_t data1;
  50     uint8_t data2;
  51     uint8_t data3;
  52
  53     uint32_t stream; /* this stream index field is included to help differentiate when address/port pairs are reused */
  54
  55     address ip_src;
  56     address ip_dst;
  57 } e_dccphdr;
  58
  59 typedef struct _dccp_flow_t {
  60         uint8_t static_flags;   /* flags */
  61         uint64_t base_seq;       /* base seq number (used by relative sequence numbers) */
  62 } dccp_flow_t;
  63
  64 struct dccp_analysis {
  65         /* These two structs are managed based on comparing the source
  66          * and destination addresses and, if they're equal, comparing
  67          * the source and destination ports.
  68          *
  69          * If the source is greater than the destination, then stuff
  70          * sent from src is in ual1.
  71          *
  72          * If the source is less than the destination, then stuff
  73          * sent from src is in ual2.
  74          *
  75          * XXX - if the addresses and ports are equal, we don't guarantee
  76          * the behavior.
  77          */
  78         dccp_flow_t     flow1;
  79         dccp_flow_t     flow2;
  80
  81         /* These pointers are set by get_dccp_conversation_data()
  82          * fwd point in the same direction as the current packet
  83          * and rev in the reverse direction
  84          */
  85         dccp_flow_t     *fwd;
  86         dccp_flow_t     *rev;
  87
  88         /* Keep track of dccp stream numbers instead of using the conversation
  89          * index (as how it was done before). This prevents gaps in the
  90          * stream index numbering
  91          */
  92         uint32_t                stream;
  93
  94         /* Remember the timestamp of the first frame seen in this dccp
  95          * conversation to be able to calculate a relative time compared
  96          * to the start of this conversation
  97          */
  98         nstime_t        ts_first;
  99
 100         /* Remember the timestamp of the frame that was last seen in this
 101          * dccp conversation to be able to calculate a delta time compared
 102          * to previous frame in this conversation
 103          */
 104         nstime_t        ts_prev;
 105 };
 106
 107 /** Get the current number of DCCP streams
 108  *
 109  * @return The number of DCCP streams
 110  */
 111 WS_DLL_PUBLIC uint32_t get_dccp_stream_count(void);
 112
 113 #ifdef __cplusplus
 114 }
 115 #endif /* __cplusplus */
 116
 117 #endif /* __PACKET_DCCP_H__ */
 118
 119 /*
 120  * Editor modelines  -  https://www.wireshark.org/tools/modelines.html
 121  *
 122  * Local variables:
 123  * c-basic-offset: 4
 124  * tab-width: 8
 125  * indent-tabs-mode: nil
 126  * End:
 127  *
 128  * vi: set shiftwidth=4 tabstop=8 expandtab:
 129  * :indentSize=4:tabSize=8:noTabs=true:
 130  */