1 #ifndef _UAPI_LINUX_DCCP_H
2 #define _UAPI_LINUX_DCCP_H
3 
4 #include <linux/types.h>
5 #include <asm/byteorder.h>
6 
7 /**
8  * struct dccp_hdr - generic part of DCCP packet header
9  *
10  * @dccph_sport - Relevant port on the endpoint that sent this packet
11  * @dccph_dport - Relevant port on the other endpoint
12  * @dccph_doff - Data Offset from the start of the DCCP header, in 32-bit words
13  * @dccph_ccval - Used by the HC-Sender CCID
14  * @dccph_cscov - Parts of the packet that are covered by the Checksum field
15  * @dccph_checksum - Internet checksum, depends on dccph_cscov
16  * @dccph_x - 0 = 24 bit sequence number, 1 = 48
17  * @dccph_type - packet type, see DCCP_PKT_ prefixed macros
18  * @dccph_seq - sequence number high or low order 24 bits, depends on dccph_x
19  */
20 struct dccp_hdr {
21 	__be16	dccph_sport,
22 		dccph_dport;
23 	__u8	dccph_doff;
24 #if defined(__LITTLE_ENDIAN_BITFIELD)
25 	__u8	dccph_cscov:4,
26 		dccph_ccval:4;
27 #elif defined(__BIG_ENDIAN_BITFIELD)
28 	__u8	dccph_ccval:4,
29 		dccph_cscov:4;
30 #else
31 #error  "Adjust your <asm/byteorder.h> defines"
32 #endif
33 	__sum16	dccph_checksum;
34 #if defined(__LITTLE_ENDIAN_BITFIELD)
35 	__u8	dccph_x:1,
36 		dccph_type:4,
37 		dccph_reserved:3;
38 #elif defined(__BIG_ENDIAN_BITFIELD)
39 	__u8	dccph_reserved:3,
40 		dccph_type:4,
41 		dccph_x:1;
42 #else
43 #error  "Adjust your <asm/byteorder.h> defines"
44 #endif
45 	__u8	dccph_seq2;
46 	__be16	dccph_seq;
47 };
48 
49 /**
50  * struct dccp_hdr_ext - the low bits of a 48 bit seq packet
51  *
52  * @dccph_seq_low - low 24 bits of a 48 bit seq packet
53  */
54 struct dccp_hdr_ext {
55 	__be32	dccph_seq_low;
56 };
57 
58 /**
59  * struct dccp_hdr_request - Connection initiation request header
60  *
61  * @dccph_req_service - Service to which the client app wants to connect
62  */
63 struct dccp_hdr_request {
64 	__be32	dccph_req_service;
65 };
66 /**
67  * struct dccp_hdr_ack_bits - acknowledgment bits common to most packets
68  *
69  * @dccph_resp_ack_nr_high - 48 bit ack number high order bits, contains GSR
70  * @dccph_resp_ack_nr_low - 48 bit ack number low order bits, contains GSR
71  */
72 struct dccp_hdr_ack_bits {
73 	__be16	dccph_reserved1;
74 	__be16	dccph_ack_nr_high;
75 	__be32	dccph_ack_nr_low;
76 };
77 /**
78  * struct dccp_hdr_response - Connection initiation response header
79  *
80  * @dccph_resp_ack - 48 bit Acknowledgment Number Subheader (5.3)
81  * @dccph_resp_service - Echoes the Service Code on a received DCCP-Request
82  */
83 struct dccp_hdr_response {
84 	struct dccp_hdr_ack_bits	dccph_resp_ack;
85 	__be32				dccph_resp_service;
86 };
87 
88 /**
89  * struct dccp_hdr_reset - Unconditionally shut down a connection
90  *
91  * @dccph_reset_ack - 48 bit Acknowledgment Number Subheader (5.6)
92  * @dccph_reset_code - one of %dccp_reset_codes
93  * @dccph_reset_data - the Data 1 ... Data 3 fields from 5.6
94  */
95 struct dccp_hdr_reset {
96 	struct dccp_hdr_ack_bits	dccph_reset_ack;
97 	__u8				dccph_reset_code,
98 					dccph_reset_data[3];
99 };
100 
101 enum dccp_pkt_type {
102 	DCCP_PKT_REQUEST = 0,
103 	DCCP_PKT_RESPONSE,
104 	DCCP_PKT_DATA,
105 	DCCP_PKT_ACK,
106 	DCCP_PKT_DATAACK,
107 	DCCP_PKT_CLOSEREQ,
108 	DCCP_PKT_CLOSE,
109 	DCCP_PKT_RESET,
110 	DCCP_PKT_SYNC,
111 	DCCP_PKT_SYNCACK,
112 	DCCP_PKT_INVALID,
113 };
114 
115 #define DCCP_NR_PKT_TYPES DCCP_PKT_INVALID
116 
dccp_packet_hdr_len(const __u8 type)117 static inline unsigned int dccp_packet_hdr_len(const __u8 type)
118 {
119 	if (type == DCCP_PKT_DATA)
120 		return 0;
121 	if (type == DCCP_PKT_DATAACK	||
122 	    type == DCCP_PKT_ACK	||
123 	    type == DCCP_PKT_SYNC	||
124 	    type == DCCP_PKT_SYNCACK	||
125 	    type == DCCP_PKT_CLOSE	||
126 	    type == DCCP_PKT_CLOSEREQ)
127 		return sizeof(struct dccp_hdr_ack_bits);
128 	if (type == DCCP_PKT_REQUEST)
129 		return sizeof(struct dccp_hdr_request);
130 	if (type == DCCP_PKT_RESPONSE)
131 		return sizeof(struct dccp_hdr_response);
132 	return sizeof(struct dccp_hdr_reset);
133 }
134 enum dccp_reset_codes {
135 	DCCP_RESET_CODE_UNSPECIFIED = 0,
136 	DCCP_RESET_CODE_CLOSED,
137 	DCCP_RESET_CODE_ABORTED,
138 	DCCP_RESET_CODE_NO_CONNECTION,
139 	DCCP_RESET_CODE_PACKET_ERROR,
140 	DCCP_RESET_CODE_OPTION_ERROR,
141 	DCCP_RESET_CODE_MANDATORY_ERROR,
142 	DCCP_RESET_CODE_CONNECTION_REFUSED,
143 	DCCP_RESET_CODE_BAD_SERVICE_CODE,
144 	DCCP_RESET_CODE_TOO_BUSY,
145 	DCCP_RESET_CODE_BAD_INIT_COOKIE,
146 	DCCP_RESET_CODE_AGGRESSION_PENALTY,
147 
148 	DCCP_MAX_RESET_CODES		/* Leave at the end!  */
149 };
150 
151 /* DCCP options */
152 enum {
153 	DCCPO_PADDING = 0,
154 	DCCPO_MANDATORY = 1,
155 	DCCPO_MIN_RESERVED = 3,
156 	DCCPO_MAX_RESERVED = 31,
157 	DCCPO_CHANGE_L = 32,
158 	DCCPO_CONFIRM_L = 33,
159 	DCCPO_CHANGE_R = 34,
160 	DCCPO_CONFIRM_R = 35,
161 	DCCPO_NDP_COUNT = 37,
162 	DCCPO_ACK_VECTOR_0 = 38,
163 	DCCPO_ACK_VECTOR_1 = 39,
164 	DCCPO_TIMESTAMP = 41,
165 	DCCPO_TIMESTAMP_ECHO = 42,
166 	DCCPO_ELAPSED_TIME = 43,
167 	DCCPO_MAX = 45,
168 	DCCPO_MIN_RX_CCID_SPECIFIC = 128,	/* from sender to receiver */
169 	DCCPO_MAX_RX_CCID_SPECIFIC = 191,
170 	DCCPO_MIN_TX_CCID_SPECIFIC = 192,	/* from receiver to sender */
171 	DCCPO_MAX_TX_CCID_SPECIFIC = 255,
172 };
173 /* maximum size of a single TLV-encoded DCCP option (sans type/len bytes) */
174 #define DCCP_SINGLE_OPT_MAXLEN	253
175 
176 /* DCCP CCIDS */
177 enum {
178 	DCCPC_CCID2 = 2,
179 	DCCPC_CCID3 = 3,
180 };
181 
182 /* DCCP features (RFC 4340 section 6.4) */
183 enum dccp_feature_numbers {
184 	DCCPF_RESERVED = 0,
185 	DCCPF_CCID = 1,
186 	DCCPF_SHORT_SEQNOS = 2,
187 	DCCPF_SEQUENCE_WINDOW = 3,
188 	DCCPF_ECN_INCAPABLE = 4,
189 	DCCPF_ACK_RATIO = 5,
190 	DCCPF_SEND_ACK_VECTOR = 6,
191 	DCCPF_SEND_NDP_COUNT = 7,
192 	DCCPF_MIN_CSUM_COVER = 8,
193 	DCCPF_DATA_CHECKSUM = 9,
194 	/* 10-127 reserved */
195 	DCCPF_MIN_CCID_SPECIFIC = 128,
196 	DCCPF_SEND_LEV_RATE = 192,	/* RFC 4342, sec. 8.4 */
197 	DCCPF_MAX_CCID_SPECIFIC = 255,
198 };
199 
200 /* DCCP socket control message types for cmsg */
201 enum dccp_cmsg_type {
202 	DCCP_SCM_PRIORITY = 1,
203 	DCCP_SCM_QPOLICY_MAX = 0xFFFF,
204 	/* ^-- Up to here reserved exclusively for qpolicy parameters */
205 	DCCP_SCM_MAX
206 };
207 
208 /* DCCP priorities for outgoing/queued packets */
209 enum dccp_packet_dequeueing_policy {
210 	DCCPQ_POLICY_SIMPLE,
211 	DCCPQ_POLICY_PRIO,
212 	DCCPQ_POLICY_MAX
213 };
214 
215 /* DCCP socket options */
216 #define DCCP_SOCKOPT_PACKET_SIZE	1 /* XXX deprecated, without effect */
217 #define DCCP_SOCKOPT_SERVICE		2
218 #define DCCP_SOCKOPT_CHANGE_L		3
219 #define DCCP_SOCKOPT_CHANGE_R		4
220 #define DCCP_SOCKOPT_GET_CUR_MPS	5
221 #define DCCP_SOCKOPT_SERVER_TIMEWAIT	6
222 #define DCCP_SOCKOPT_SEND_CSCOV		10
223 #define DCCP_SOCKOPT_RECV_CSCOV		11
224 #define DCCP_SOCKOPT_AVAILABLE_CCIDS	12
225 #define DCCP_SOCKOPT_CCID		13
226 #define DCCP_SOCKOPT_TX_CCID		14
227 #define DCCP_SOCKOPT_RX_CCID		15
228 #define DCCP_SOCKOPT_QPOLICY_ID		16
229 #define DCCP_SOCKOPT_QPOLICY_TXQLEN	17
230 #define DCCP_SOCKOPT_CCID_RX_INFO	128
231 #define DCCP_SOCKOPT_CCID_TX_INFO	192
232 
233 /* maximum number of services provided on the same listening port */
234 #define DCCP_SERVICE_LIST_MAX_LEN      32
235 
236 
237 #endif /* _UAPI_LINUX_DCCP_H */
238