[DCCP]: Initial implementation
[linux-3.10.git] / include / linux / dccp.h
1 #ifndef _LINUX_DCCP_H
2 #define _LINUX_DCCP_H
3
4 #include <linux/in.h>
5 #include <linux/list.h>
6 #include <linux/types.h>
7 #include <linux/uio.h>
8 #include <linux/workqueue.h>
9
10 #include <net/inet_connection_sock.h>
11 #include <net/sock.h>
12 #include <net/tcp_states.h>
13 #include <net/tcp.h>
14
15 /* FIXME: this is utterly wrong */
16 struct sockaddr_dccp {
17         struct sockaddr_in      in;
18         unsigned int            service;
19 };
20
21 enum dccp_state {
22         DCCP_OPEN       = TCP_ESTABLISHED,
23         DCCP_REQUESTING = TCP_SYN_SENT,
24         DCCP_PARTOPEN   = TCP_FIN_WAIT1, /* FIXME:
25                                             This mapping is horrible, but TCP has
26                                             no matching state for DCCP_PARTOPEN,
27                                             as TCP_SYN_RECV is already used by
28                                             DCCP_RESPOND, why don't stop using TCP
29                                             mapping of states? OK, now we don't use
30                                             sk_stream_sendmsg anymore, so doesn't
31                                             seem to exist any reason for us to
32                                             do the TCP mapping here */
33         DCCP_LISTEN     = TCP_LISTEN,
34         DCCP_RESPOND    = TCP_SYN_RECV,
35         DCCP_CLOSING    = TCP_CLOSING,
36         DCCP_TIME_WAIT  = TCP_TIME_WAIT,
37         DCCP_CLOSED     = TCP_CLOSE,
38         DCCP_MAX_STATES = TCP_MAX_STATES,
39 };
40
41 #define DCCP_STATE_MASK 0xf
42 #define DCCP_ACTION_FIN (1<<7)
43
44 enum {
45         DCCPF_OPEN       = TCPF_ESTABLISHED,
46         DCCPF_REQUESTING = TCPF_SYN_SENT,
47         DCCPF_PARTOPEN   = TCPF_FIN_WAIT1,
48         DCCPF_LISTEN     = TCPF_LISTEN,
49         DCCPF_RESPOND    = TCPF_SYN_RECV,
50         DCCPF_CLOSING    = TCPF_CLOSING,
51         DCCPF_TIME_WAIT  = TCPF_TIME_WAIT,
52         DCCPF_CLOSED     = TCPF_CLOSE,
53 };
54
55 /**
56  * struct dccp_hdr - generic part of DCCP packet header
57  *
58  * @dccph_sport - Relevant port on the endpoint that sent this packet
59  * @dccph_dport - Relevant port on the other endpoint
60  * @dccph_doff - Data Offset from the start of the DCCP header, in 32-bit words
61  * @dccph_ccval - Used by the HC-Sender CCID
62  * @dccph_cscov - Parts of the packet that are covered by the Checksum field
63  * @dccph_checksum - Internet checksum, depends on dccph_cscov
64  * @dccph_x - 0 = 24 bit sequence number, 1 = 48
65  * @dccph_type - packet type, see DCCP_PKT_ prefixed macros
66  * @dccph_seq - sequence number high or low order 24 bits, depends on dccph_x
67  */
68 struct dccp_hdr {
69         __u16   dccph_sport,
70                 dccph_dport;
71         __u8    dccph_doff;
72 #if defined(__LITTLE_ENDIAN_BITFIELD)
73         __u8    dccph_cscov:4,
74                 dccph_ccval:4;
75 #elif defined(__BIG_ENDIAN_BITFIELD)
76         __u8    dccph_ccval:4,
77                 dccph_cscov:4;
78 #else
79 #error  "Adjust your <asm/byteorder.h> defines"
80 #endif
81         __u16   dccph_checksum;
82 #if defined(__LITTLE_ENDIAN_BITFIELD)
83         __u32   dccph_x:1,
84                 dccph_type:4,
85                 dccph_reserved:3,
86                 dccph_seq:24;
87 #elif defined(__BIG_ENDIAN_BITFIELD)
88         __u32   dccph_reserved:3,
89                 dccph_type:4,
90                 dccph_x:1,
91                 dccph_seq:24;
92 #else
93 #error  "Adjust your <asm/byteorder.h> defines"
94 #endif
95 };
96
97 static inline struct dccp_hdr *dccp_hdr(const struct sk_buff *skb)
98 {
99         return (struct dccp_hdr *)skb->h.raw;
100 }
101
102 /**
103  * struct dccp_hdr_ext - the low bits of a 48 bit seq packet
104  *
105  * @dccph_seq_low - low 24 bits of a 48 bit seq packet
106  */
107 struct dccp_hdr_ext {
108         __u32   dccph_seq_low;
109 };
110
111 static inline struct dccp_hdr_ext *dccp_hdrx(const struct sk_buff *skb)
112 {
113         return (struct dccp_hdr_ext *)(skb->h.raw + sizeof(struct dccp_hdr));
114 }
115
116 static inline unsigned int dccp_basic_hdr_len(const struct sk_buff *skb)
117 {
118         const struct dccp_hdr *dh = dccp_hdr(skb);
119         return sizeof(*dh) + (dh->dccph_x ? sizeof(struct dccp_hdr_ext) : 0);
120 }
121
122 static inline __u64 dccp_hdr_seq(const struct sk_buff *skb)
123 {
124         const struct dccp_hdr *dh = dccp_hdr(skb);
125 #if defined(__LITTLE_ENDIAN_BITFIELD)
126         __u64 seq_nr = ntohl(dh->dccph_seq << 8);
127 #elif defined(__BIG_ENDIAN_BITFIELD)
128         __u64 seq_nr = ntohl(dh->dccph_seq);
129 #else
130 #error  "Adjust your <asm/byteorder.h> defines"
131 #endif
132
133         if (dh->dccph_x != 0)
134                 seq_nr = (seq_nr << 32) + ntohl(dccp_hdrx(skb)->dccph_seq_low);
135
136         return seq_nr;
137 }
138
139 /**
140  * struct dccp_hdr_request - Conection initiation request header
141  *
142  * @dccph_req_service - Service to which the client app wants to connect
143  * @dccph_req_options - list of options (must be a multiple of 32 bits
144  */
145 struct dccp_hdr_request {
146         __u32   dccph_req_service;
147 };
148
149 static inline struct dccp_hdr_request *dccp_hdr_request(struct sk_buff *skb)
150 {
151         return (struct dccp_hdr_request *)(skb->h.raw + dccp_basic_hdr_len(skb));
152 }
153
154 /**
155  * struct dccp_hdr_ack_bits - acknowledgment bits common to most packets
156  *
157  * @dccph_resp_ack_nr_high - 48 bit ack number high order bits, contains GSR
158  * @dccph_resp_ack_nr_low - 48 bit ack number low order bits, contains GSR
159  */
160 struct dccp_hdr_ack_bits {
161         __u32   dccph_reserved1:8,
162                 dccph_ack_nr_high:24;
163         __u32   dccph_ack_nr_low;
164 };
165
166 static inline struct dccp_hdr_ack_bits *dccp_hdr_ack_bits(const struct sk_buff *skb)
167 {
168         return (struct dccp_hdr_ack_bits *)(skb->h.raw + dccp_basic_hdr_len(skb));
169 }
170
171 static inline u64 dccp_hdr_ack_seq(const struct sk_buff *skb)
172 {
173         const struct dccp_hdr_ack_bits *dhack = dccp_hdr_ack_bits(skb);
174 #if defined(__LITTLE_ENDIAN_BITFIELD)
175         return (((u64)ntohl(dhack->dccph_ack_nr_high << 8)) << 32) + ntohl(dhack->dccph_ack_nr_low);
176 #elif defined(__BIG_ENDIAN_BITFIELD)
177         return (((u64)ntohl(dhack->dccph_ack_nr_high)) << 32) + ntohl(dhack->dccph_ack_nr_low);
178 #else
179 #error  "Adjust your <asm/byteorder.h> defines"
180 #endif
181 }
182
183 /**
184  * struct dccp_hdr_response - Conection initiation response header
185  *
186  * @dccph_resp_ack_nr_high - 48 bit ack number high order bits, contains GSR
187  * @dccph_resp_ack_nr_low - 48 bit ack number low order bits, contains GSR
188  * @dccph_resp_service - Echoes the Service Code on a received DCCP-Request
189  * @dccph_resp_options - list of options (must be a multiple of 32 bits
190  */
191 struct dccp_hdr_response {
192         struct dccp_hdr_ack_bits        dccph_resp_ack;
193         __u32                           dccph_resp_service;
194 };
195
196 static inline struct dccp_hdr_response *dccp_hdr_response(struct sk_buff *skb)
197 {
198         return (struct dccp_hdr_response *)(skb->h.raw + dccp_basic_hdr_len(skb));
199 }
200
201 /**
202  * struct dccp_hdr_reset - Unconditionally shut down a connection
203  *
204  * @dccph_reset_service - Echoes the Service Code on a received DCCP-Request
205  * @dccph_reset_options - list of options (must be a multiple of 32 bits
206  */
207 struct dccp_hdr_reset {
208         struct dccp_hdr_ack_bits        dccph_reset_ack;
209         __u8                            dccph_reset_code,
210                                         dccph_reset_data[3];
211 };
212
213 static inline struct dccp_hdr_reset *dccp_hdr_reset(struct sk_buff *skb)
214 {
215         return (struct dccp_hdr_reset *)(skb->h.raw + dccp_basic_hdr_len(skb));
216 }
217
218 enum dccp_pkt_type {
219         DCCP_PKT_REQUEST = 0,
220         DCCP_PKT_RESPONSE,
221         DCCP_PKT_DATA,
222         DCCP_PKT_ACK,
223         DCCP_PKT_DATAACK,
224         DCCP_PKT_CLOSEREQ,
225         DCCP_PKT_CLOSE,
226         DCCP_PKT_RESET,
227         DCCP_PKT_SYNC,
228         DCCP_PKT_SYNCACK,
229         DCCP_PKT_INVALID,
230 };
231
232 #define DCCP_NR_PKT_TYPES DCCP_PKT_INVALID
233
234 static inline unsigned int dccp_packet_hdr_len(const __u8 type)
235 {
236         if (type == DCCP_PKT_DATA)
237                 return 0;
238         if (type == DCCP_PKT_DATAACK    ||
239             type == DCCP_PKT_ACK        ||
240             type == DCCP_PKT_SYNC       ||
241             type == DCCP_PKT_SYNCACK    ||
242             type == DCCP_PKT_CLOSE      ||
243             type == DCCP_PKT_CLOSEREQ)
244                 return sizeof(struct dccp_hdr_ack_bits);
245         if (type == DCCP_PKT_REQUEST)
246                 return sizeof(struct dccp_hdr_request);
247         if (type == DCCP_PKT_RESPONSE)
248                 return sizeof(struct dccp_hdr_response);
249         return sizeof(struct dccp_hdr_reset);
250 }
251
252 static inline unsigned int dccp_hdr_len(const struct sk_buff *skb)
253 {
254         return dccp_basic_hdr_len(skb) +
255                dccp_packet_hdr_len(dccp_hdr(skb)->dccph_type);
256 }
257
258 enum dccp_reset_codes {
259         DCCP_RESET_CODE_UNSPECIFIED = 0,
260         DCCP_RESET_CODE_CLOSED,
261         DCCP_RESET_CODE_ABORTED,
262         DCCP_RESET_CODE_NO_CONNECTION,
263         DCCP_RESET_CODE_PACKET_ERROR,
264         DCCP_RESET_CODE_OPTION_ERROR,
265         DCCP_RESET_CODE_MANDATORY_ERROR,
266         DCCP_RESET_CODE_CONNECTION_REFUSED,
267         DCCP_RESET_CODE_BAD_SERVICE_CODE,
268         DCCP_RESET_CODE_TOO_BUSY,
269         DCCP_RESET_CODE_BAD_INIT_COOKIE,
270         DCCP_RESET_CODE_AGGRESSION_PENALTY,
271 };
272
273 /* DCCP options */
274 enum {
275         DCCPO_PADDING = 0,
276         DCCPO_MANDATORY = 1,
277         DCCPO_MIN_RESERVED = 3,
278         DCCPO_MAX_RESERVED = 31,
279         DCCPO_NDP_COUNT = 37,
280         DCCPO_ACK_VECTOR_0 = 38,
281         DCCPO_ACK_VECTOR_1 = 39,
282         DCCPO_TIMESTAMP = 41,
283         DCCPO_TIMESTAMP_ECHO = 42,
284         DCCPO_ELAPSED_TIME = 43,
285         DCCPO_MAX = 45,
286         DCCPO_MIN_CCID_SPECIFIC = 128,
287         DCCPO_MAX_CCID_SPECIFIC = 255,
288 };
289
290 /* DCCP features */
291 enum {
292         DCCPF_RESERVED = 0,
293         DCCPF_SEQUENCE_WINDOW = 3,
294         DCCPF_SEND_ACK_VECTOR = 6,
295         DCCPF_SEND_NDP_COUNT = 7,
296         /* 10-127 reserved */
297         DCCPF_MIN_CCID_SPECIFIC = 128,
298         DCCPF_MAX_CCID_SPECIFIC = 255,
299 };
300
301 /* initial values for each feature */
302 #define DCCPF_INITIAL_SEQUENCE_WINDOW           100
303 /* FIXME: for now we're using CCID 3 (TFRC) */
304 #define DCCPF_INITIAL_CCID                      3
305 #define DCCPF_INITIAL_SEND_ACK_VECTOR           0
306 /* FIXME: for now we're default to 1 but it should really be 0 */
307 #define DCCPF_INITIAL_SEND_NDP_COUNT            1
308
309 #define DCCP_NDP_LIMIT 0xFFFFFF
310
311 /**
312   * struct dccp_options - option values for a DCCP connection
313   *     @dccpo_sequence_window - Sequence Window Feature (section 7.5.2)
314   *     @dccpo_ccid - Congestion Control Id (CCID) (section 10)
315   *     @dccpo_send_ack_vector - Send Ack Vector Feature (section 11.5)
316   *     @dccpo_send_ndp_count - Send NDP Count Feature (7.7.2)
317   */
318 struct dccp_options {
319         __u64   dccpo_sequence_window;
320         __u8    dccpo_ccid;
321         __u8    dccpo_send_ack_vector;
322         __u8    dccpo_send_ndp_count;
323 };
324
325 extern void __dccp_options_init(struct dccp_options *dccpo);
326 extern void dccp_options_init(struct dccp_options *dccpo);
327 extern int dccp_parse_options(struct sock *sk, struct sk_buff *skb);
328
329 struct dccp_request_sock {
330         struct inet_request_sock dreq_inet_rsk;
331         __u64                    dreq_iss;
332         __u64                    dreq_isr;
333         __u32                    dreq_service;
334 };
335
336 static inline struct dccp_request_sock *dccp_rsk(const struct request_sock *req)
337 {
338         return (struct dccp_request_sock *)req;
339 }
340
341 /* Read about the ECN nonce to see why it is 253 */
342 #define DCCP_MAX_ACK_VECTOR_LEN 253
343
344 struct dccp_options_received {
345         u32     dccpor_ndp:24,
346                 dccpor_ack_vector_len:8;
347         u32     dccpor_ack_vector_idx:10;
348         /* 22 bits hole, try to pack */
349         u32     dccpor_timestamp;
350         u32     dccpor_timestamp_echo;
351         u32     dccpor_elapsed_time;
352 };
353
354 struct ccid;
355
356 enum dccp_role {
357         DCCP_ROLE_UNDEFINED,
358         DCCP_ROLE_LISTEN,
359         DCCP_ROLE_CLIENT,
360         DCCP_ROLE_SERVER,
361 };
362
363 /**
364  * struct dccp_sock - DCCP socket state
365  *
366  * @dccps_swl - sequence number window low
367  * @dccps_swh - sequence number window high
368  * @dccps_awl - acknowledgement number window low
369  * @dccps_awh - acknowledgement number window high
370  * @dccps_iss - initial sequence number sent
371  * @dccps_isr - initial sequence number received
372  * @dccps_osr - first OPEN sequence number received
373  * @dccps_gss - greatest sequence number sent
374  * @dccps_gsr - greatest valid sequence number received
375  * @dccps_gar - greatest valid ack number received on a non-Sync; initialized to %dccps_iss
376  * @dccps_timestamp_time - time of latest TIMESTAMP option
377  * @dccps_timestamp_echo - latest timestamp received on a TIMESTAMP option
378  * @dccps_ext_header_len - network protocol overhead (IP/IPv6 options)
379  * @dccps_pmtu_cookie - Last pmtu seen by socket
380  * @dccps_avg_packet_size - FIXME: has to be set by the app thru some setsockopt or ioctl, CCID3 uses it
381  * @dccps_role - Role of this sock, one of %dccp_role
382  * @dccps_ndp_count - number of Non Data Packets since last data packet
383  * @dccps_hc_rx_ackpkts - receiver half connection acked packets
384  */
385 struct dccp_sock {
386         /* inet_connection_sock has to be the first member of dccp_sock */
387         struct inet_connection_sock     dccps_inet_connection;
388         __u64                           dccps_swl;
389         __u64                           dccps_swh;
390         __u64                           dccps_awl;
391         __u64                           dccps_awh;
392         __u64                           dccps_iss;
393         __u64                           dccps_isr;
394         __u64                           dccps_osr;
395         __u64                           dccps_gss;
396         __u64                           dccps_gsr;
397         __u64                           dccps_gar;
398         unsigned long                   dccps_service;
399         unsigned long                   dccps_timestamp_time;
400         __u32                           dccps_timestamp_echo;
401         __u32                           dccps_avg_packet_size;
402         unsigned long                   dccps_ndp_count;
403         __u16                           dccps_ext_header_len;
404         __u32                           dccps_pmtu_cookie;
405         __u32                           dccps_mss_cache;
406         struct dccp_options             dccps_options;
407         struct dccp_ackpkts             *dccps_hc_rx_ackpkts;
408         void                            *dccps_hc_rx_ccid_private;
409         void                            *dccps_hc_tx_ccid_private;
410         struct ccid                     *dccps_hc_rx_ccid;
411         struct ccid                     *dccps_hc_tx_ccid;
412         struct dccp_options_received    dccps_options_received;
413         enum dccp_role                  dccps_role:2;
414 };
415  
416 static inline struct dccp_sock *dccp_sk(const struct sock *sk)
417 {
418         return (struct dccp_sock *)sk;
419 }
420
421 static inline const char *dccp_role(const struct sock *sk)
422 {
423         switch (dccp_sk(sk)->dccps_role) {
424         case DCCP_ROLE_UNDEFINED: return "undefined";
425         case DCCP_ROLE_LISTEN:    return "listen";
426         case DCCP_ROLE_SERVER:    return "server";
427         case DCCP_ROLE_CLIENT:    return "client";
428         }
429         return NULL;
430 }
431
432 #endif /* _LINUX_DCCP_H */