1 /* @(#) $Header: /tcpdump/master/tcpdump/dccp.h,v 1.1.2.4 2006/05/12 01:46:17 guy Exp $ (LBL) */ 2 /* 3 * Copyright (C) Arnaldo Carvalho de Melo 2004 4 * Copyright (C) Ian McDonald 2005 <iam4 (at) cs.waikato.ac.nz> 5 * Copyright (C) Yoshifumi Nishida 2005 6 * 7 * This software may be distributed either under the terms of the 8 * BSD-style license that accompanies tcpdump or the GNU GPL version 2 9 */ 10 11 #ifndef __DCCP_HDR__ 12 #define __DCCP_HDR__ 13 14 /** 15 * struct dccp_hdr - generic part of DCCP packet header 16 * 17 * @dccph_sport - Relevant port on the endpoint that sent this packet 18 * @dccph_dport - Relevant port on the other endpoint 19 * @dccph_doff - Data Offset from the start of the DCCP header, in 32-bit words 20 * @dccph_ccval - Used by the HC-Sender CCID 21 * @dccph_cscov - Parts of the packet that are covered by the Checksum field 22 * @dccph_checksum - Internet checksum, depends on dccph_cscov 23 * @dccph_x - 0 = 24 bit sequence number, 1 = 48 24 * @dccph_type - packet type, see DCCP_PKT_ prefixed macros 25 * @dccph_seq - sequence number high or low order 24 bits, depends on dccph_x 26 */ 27 struct dccp_hdr { 28 u_int16_t dccph_sport, 29 dccph_dport; 30 u_int8_t dccph_doff; 31 u_int8_t dccph_ccval_cscov; 32 u_int16_t dccph_checksum; 33 union { 34 u_int8_t dccph_xtr; 35 u_int32_t dccph_seq; 36 } dccph_xtrs; 37 }; 38 39 #define DCCPH_CCVAL(dh) (((dh)->dccph_ccval_cscov) & 0x0F) 40 #define DCCPH_CSCOV(dh) (((dh)->dccph_ccval_cscov >> 4) & 0x0F) 41 42 #define DCCPH_X(dh) ((dh)->dccph_xtrs.dccph_xtr & 1) 43 #define DCCPH_TYPE(dh) (((dh)->dccph_xtrs.dccph_xtr >> 1) & 0xF) 44 #define DCCPH_SEQ(dh) (((dh)->dccph_xtrs.dccph_seq) >> 8) 45 46 /** 47 * struct dccp_hdr_ext - the low bits of a 48 bit seq packet 48 * 49 * @dccph_seq_low - low 24 bits of a 48 bit seq packet 50 */ 51 struct dccp_hdr_ext { 52 u_int32_t dccph_seq_low; 53 }; 54 55 /** 56 * struct dccp_hdr_request - Conection initiation request header 57 * 58 * @dccph_req_service - Service to which the client app wants to connect 59 */ 60 struct dccp_hdr_request { 61 u_int32_t dccph_req_service; 62 }; 63 64 /** 65 * struct dccp_hdr_ack_bits - acknowledgment bits common to most packets 66 * 67 * @dccph_resp_ack_nr_high - 48 bit ack number high order bits, contains GSR 68 * @dccph_resp_ack_nr_low - 48 bit ack number low order bits, contains GSR 69 */ 70 struct dccp_hdr_ack_bits { 71 u_int32_t dccph_ra; 72 u_int32_t dccph_ack_nr_low; 73 }; 74 75 #define DCCPH_ACK(dh_ack) ((dh_ack)->dccph_ra >> 8) 76 77 /** 78 * struct dccp_hdr_response - Conection initiation response header 79 * 80 * @dccph_resp_ack_nr_high - 48 bit ack number high order bits, contains GSR 81 * @dccph_resp_ack_nr_low - 48 bit ack number low order bits, contains GSR 82 * @dccph_resp_service - Echoes the Service Code on a received DCCP-Request 83 */ 84 struct dccp_hdr_response { 85 struct dccp_hdr_ack_bits dccph_resp_ack; 86 u_int32_t dccph_resp_service; 87 }; 88 89 #if 0 90 static inline struct dccp_hdr_data *dccp_hdr_data(struct dccp_hdr *hdrg) 91 { 92 const int ext = DCCPH_X(hdrg) ? sizeof(struct dccp_hdr_ext) : 0; 93 94 return (struct dccp_hdr_data *)(((u_char *)hdrg) + sizeof(hdrg) + ext); 95 } 96 #endif 97 98 /** 99 * struct dccp_hdr_reset - Unconditionally shut down a connection 100 * 101 * @dccph_reset_service - Echoes the Service Code on a received DCCP-Request 102 */ 103 struct dccp_hdr_reset { 104 struct dccp_hdr_ack_bits dccph_reset_ack; 105 u_int8_t dccph_reset_code, 106 dccph_reset_data[3]; 107 }; 108 109 enum dccp_pkt_type { 110 DCCP_PKT_REQUEST = 0, 111 DCCP_PKT_RESPONSE, 112 DCCP_PKT_DATA, 113 DCCP_PKT_ACK, 114 DCCP_PKT_DATAACK, 115 DCCP_PKT_CLOSEREQ, 116 DCCP_PKT_CLOSE, 117 DCCP_PKT_RESET, 118 DCCP_PKT_SYNC, 119 DCCP_PKT_SYNCACK, 120 DCCP_PKT_INVALID 121 }; 122 123 enum dccp_reset_codes { 124 DCCP_RESET_CODE_UNSPECIFIED = 0, 125 DCCP_RESET_CODE_CLOSED, 126 DCCP_RESET_CODE_ABORTED, 127 DCCP_RESET_CODE_NO_CONNECTION, 128 DCCP_RESET_CODE_PACKET_ERROR, 129 DCCP_RESET_CODE_OPTION_ERROR, 130 DCCP_RESET_CODE_MANDATORY_ERROR, 131 DCCP_RESET_CODE_CONNECTION_REFUSED, 132 DCCP_RESET_CODE_BAD_SERVICE_CODE, 133 DCCP_RESET_CODE_TOO_BUSY, 134 DCCP_RESET_CODE_BAD_INIT_COOKIE, 135 DCCP_RESET_CODE_AGGRESSION_PENALTY, 136 __DCCP_RESET_CODE_LAST 137 }; 138 139 #endif /* __DCCP_HDR__ */ 140