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/* @(#) $Header: /tcpdump/master/tcpdump/dccp.h,v 1.2 2005-09-20 06:25:19 guy Exp $ (LBL) */
/*
* Copyright (C) Arnaldo Carvalho de Melo 2004
* Copyright (C) Ian McDonald 2005 <iam4@cs.waikato.ac.nz>
* Copyright (C) Yoshifumi Nishida 2005
*
* This software may be distributed either under the terms of the
* BSD-style license that accompanies tcpdump or the GNU GPL version 2
*/
#ifndef __DCCP_HDR__
#define __DCCP_HDR__
/**
* struct dccp_hdr - generic part of DCCP packet header
*
* @dccph_sport - Relevant port on the endpoint that sent this packet
* @dccph_dport - Relevant port on the other endpoint
* @dccph_doff - Data Offset from the start of the DCCP header, in 32-bit words
* @dccph_ccval - Used by the HC-Sender CCID
* @dccph_cscov - Parts of the packet that are covered by the Checksum field
* @dccph_checksum - Internet checksum, depends on dccph_cscov
* @dccph_x - 0 = 24 bit sequence number, 1 = 48
* @dccph_type - packet type, see DCCP_PKT_ prefixed macros
* @dccph_seq - sequence number high or low order 24 bits, depends on dccph_x
*/
struct dccp_hdr {
u_int16_t dccph_sport,
dccph_dport;
u_int8_t dccph_doff;
u_int8_t dccph_ccval_cscov;
u_int16_t dccph_checksum;
union {
u_int8_t dccph_xtr;
u_int32_t dccph_seq;
} dccph_xtrs;
};
#define DCCPH_CCVAL(dh) (((dh)->dccph_ccval_cscov) & 0x0F)
#define DCCPH_CSCOV(dh) (((dh)->dccph_ccval_cscov >> 4) & 0x0F)
#define DCCPH_X(dh) ((dh)->dccph_xtrs.dccph_xtr & 1)
#define DCCPH_TYPE(dh) (((dh)->dccph_xtrs.dccph_xtr >> 1) & 0xF)
#define DCCPH_SEQ(dh) (((dh)->dccph_xtrs.dccph_seq) >> 8)
/**
* struct dccp_hdr_ext - the low bits of a 48 bit seq packet
*
* @dccph_seq_low - low 24 bits of a 48 bit seq packet
*/
struct dccp_hdr_ext {
u_int32_t dccph_seq_low;
};
/**
* struct dccp_hdr_request - Conection initiation request header
*
* @dccph_req_service - Service to which the client app wants to connect
*/
struct dccp_hdr_request {
u_int32_t dccph_req_service;
};
/**
* struct dccp_hdr_ack_bits - acknowledgment bits common to most packets
*
* @dccph_resp_ack_nr_high - 48 bit ack number high order bits, contains GSR
* @dccph_resp_ack_nr_low - 48 bit ack number low order bits, contains GSR
*/
struct dccp_hdr_ack_bits {
u_int32_t dccph_ra;
u_int32_t dccph_ack_nr_low;
};
#define DCCPH_ACK(dh_ack) ((dh_ack)->dccph_ra >> 8)
/**
* struct dccp_hdr_response - Conection initiation response header
*
* @dccph_resp_ack_nr_high - 48 bit ack number high order bits, contains GSR
* @dccph_resp_ack_nr_low - 48 bit ack number low order bits, contains GSR
* @dccph_resp_service - Echoes the Service Code on a received DCCP-Request
*/
struct dccp_hdr_response {
struct dccp_hdr_ack_bits dccph_resp_ack;
u_int32_t dccph_resp_service;
};
static inline struct dccp_hdr_data *dccp_hdr_data(struct dccp_hdr *hdrg)
{
const int ext = DCCPH_X(hdrg) ? sizeof(struct dccp_hdr_ext) : 0;
return (struct dccp_hdr_data *)(((u_char *)hdrg) + sizeof(hdrg) + ext);
}
/**
* struct dccp_hdr_reset - Unconditionally shut down a connection
*
* @dccph_reset_service - Echoes the Service Code on a received DCCP-Request
*/
struct dccp_hdr_reset {
struct dccp_hdr_ack_bits dccph_reset_ack;
u_int8_t dccph_reset_code,
dccph_reset_data[3];
};
enum dccp_pkt_type {
DCCP_PKT_REQUEST = 0,
DCCP_PKT_RESPONSE,
DCCP_PKT_DATA,
DCCP_PKT_ACK,
DCCP_PKT_DATAACK,
DCCP_PKT_CLOSEREQ,
DCCP_PKT_CLOSE,
DCCP_PKT_RESET,
DCCP_PKT_SYNC,
DCCP_PKT_SYNCACK,
DCCP_PKT_INVALID,
};
enum dccp_reset_codes {
DCCP_RESET_CODE_UNSPECIFIED = 0,
DCCP_RESET_CODE_CLOSED,
DCCP_RESET_CODE_ABORTED,
DCCP_RESET_CODE_NO_CONNECTION,
DCCP_RESET_CODE_PACKET_ERROR,
DCCP_RESET_CODE_OPTION_ERROR,
DCCP_RESET_CODE_MANDATORY_ERROR,
DCCP_RESET_CODE_CONNECTION_REFUSED,
DCCP_RESET_CODE_BAD_SERVICE_CODE,
DCCP_RESET_CODE_TOO_BUSY,
DCCP_RESET_CODE_BAD_INIT_COOKIE,
DCCP_RESET_CODE_AGGRESSION_PENALTY,
__DCCP_RESET_CODE_LAST,
};
#endif /* __DCCP_HDR__ */
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