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 */
20struct 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 */
54struct 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 */
63struct 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 */
72struct 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 */
83struct 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 */
95struct dccp_hdr_reset {
96	struct dccp_hdr_ack_bits	dccph_reset_ack;
97	__u8				dccph_reset_code,
98					dccph_reset_data[3];
99};
100
101enum 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
117static 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}
134enum 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 */
152enum {
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 */
177enum {
178	DCCPC_CCID2 = 2,
179	DCCPC_CCID3 = 3,
180};
181
182/* DCCP features (RFC 4340 section 6.4) */
183enum 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 */
201enum 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 */
209enum 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