[DCCP]: Tidy-up -- minisock initialisation
[safe/jmp/linux-2.6] / include / linux / dccp.h
1 #ifndef _LINUX_DCCP_H
2 #define _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
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
149 /* DCCP options */
150 enum {
151         DCCPO_PADDING = 0,
152         DCCPO_MANDATORY = 1,
153         DCCPO_MIN_RESERVED = 3,
154         DCCPO_MAX_RESERVED = 31,
155         DCCPO_CHANGE_L = 32,
156         DCCPO_CONFIRM_L = 33,
157         DCCPO_CHANGE_R = 34,
158         DCCPO_CONFIRM_R = 35,
159         DCCPO_NDP_COUNT = 37,
160         DCCPO_ACK_VECTOR_0 = 38,
161         DCCPO_ACK_VECTOR_1 = 39,
162         DCCPO_TIMESTAMP = 41,
163         DCCPO_TIMESTAMP_ECHO = 42,
164         DCCPO_ELAPSED_TIME = 43,
165         DCCPO_MAX = 45,
166         DCCPO_MIN_CCID_SPECIFIC = 128,
167         DCCPO_MAX_CCID_SPECIFIC = 255,
168 };
169
170 /* DCCP CCIDS */
171 enum {
172         DCCPC_CCID2 = 2,
173         DCCPC_CCID3 = 3,
174 };
175
176 /* DCCP features (RFC 4340 section 6.4) */
177 enum {
178         DCCPF_RESERVED = 0,
179         DCCPF_CCID = 1,
180         DCCPF_SHORT_SEQNOS = 2,         /* XXX: not yet implemented */
181         DCCPF_SEQUENCE_WINDOW = 3,
182         DCCPF_ECN_INCAPABLE = 4,        /* XXX: not yet implemented */
183         DCCPF_ACK_RATIO = 5,
184         DCCPF_SEND_ACK_VECTOR = 6,
185         DCCPF_SEND_NDP_COUNT = 7,
186         DCCPF_MIN_CSUM_COVER = 8,
187         DCCPF_DATA_CHECKSUM = 9,        /* XXX: not yet implemented */
188         /* 10-127 reserved */
189         DCCPF_MIN_CCID_SPECIFIC = 128,
190         DCCPF_MAX_CCID_SPECIFIC = 255,
191 };
192
193 /* this structure is argument to DCCP_SOCKOPT_CHANGE_X */
194 struct dccp_so_feat {
195         __u8 dccpsf_feat;
196         __u8 __user *dccpsf_val;
197         __u8 dccpsf_len;
198 };
199
200 /* DCCP socket options */
201 #define DCCP_SOCKOPT_PACKET_SIZE        1 /* XXX deprecated, without effect */
202 #define DCCP_SOCKOPT_SERVICE            2
203 #define DCCP_SOCKOPT_CHANGE_L           3
204 #define DCCP_SOCKOPT_CHANGE_R           4
205 #define DCCP_SOCKOPT_GET_CUR_MPS        5
206 #define DCCP_SOCKOPT_SEND_CSCOV         10
207 #define DCCP_SOCKOPT_RECV_CSCOV         11
208 #define DCCP_SOCKOPT_CCID_RX_INFO       128
209 #define DCCP_SOCKOPT_CCID_TX_INFO       192
210
211 /* maximum number of services provided on the same listening port */
212 #define DCCP_SERVICE_LIST_MAX_LEN      32
213
214 #ifdef __KERNEL__
215
216 #include <linux/in.h>
217 #include <linux/ktime.h>
218 #include <linux/list.h>
219 #include <linux/uio.h>
220 #include <linux/workqueue.h>
221
222 #include <net/inet_connection_sock.h>
223 #include <net/inet_sock.h>
224 #include <net/inet_timewait_sock.h>
225 #include <net/tcp_states.h>
226
227 enum dccp_state {
228         DCCP_OPEN       = TCP_ESTABLISHED,
229         DCCP_REQUESTING = TCP_SYN_SENT,
230         DCCP_PARTOPEN   = TCP_FIN_WAIT1, /* FIXME:
231                                             This mapping is horrible, but TCP has
232                                             no matching state for DCCP_PARTOPEN,
233                                             as TCP_SYN_RECV is already used by
234                                             DCCP_RESPOND, why don't stop using TCP
235                                             mapping of states? OK, now we don't use
236                                             sk_stream_sendmsg anymore, so doesn't
237                                             seem to exist any reason for us to
238                                             do the TCP mapping here */
239         DCCP_LISTEN     = TCP_LISTEN,
240         DCCP_RESPOND    = TCP_SYN_RECV,
241         DCCP_CLOSING    = TCP_CLOSING,
242         DCCP_TIME_WAIT  = TCP_TIME_WAIT,
243         DCCP_CLOSED     = TCP_CLOSE,
244         DCCP_MAX_STATES = TCP_MAX_STATES,
245 };
246
247 #define DCCP_STATE_MASK 0xf
248 #define DCCP_ACTION_FIN (1<<7)
249
250 enum {
251         DCCPF_OPEN       = TCPF_ESTABLISHED,
252         DCCPF_REQUESTING = TCPF_SYN_SENT,
253         DCCPF_PARTOPEN   = TCPF_FIN_WAIT1,
254         DCCPF_LISTEN     = TCPF_LISTEN,
255         DCCPF_RESPOND    = TCPF_SYN_RECV,
256         DCCPF_CLOSING    = TCPF_CLOSING,
257         DCCPF_TIME_WAIT  = TCPF_TIME_WAIT,
258         DCCPF_CLOSED     = TCPF_CLOSE,
259 };
260
261 static inline struct dccp_hdr *dccp_hdr(const struct sk_buff *skb)
262 {
263         return (struct dccp_hdr *)skb_transport_header(skb);
264 }
265
266 static inline struct dccp_hdr *dccp_zeroed_hdr(struct sk_buff *skb, int headlen)
267 {
268         skb_push(skb, headlen);
269         skb_reset_transport_header(skb);
270         return memset(skb_transport_header(skb), 0, headlen);
271 }
272
273 static inline struct dccp_hdr_ext *dccp_hdrx(const struct sk_buff *skb)
274 {
275         return (struct dccp_hdr_ext *)(skb_transport_header(skb) +
276                                        sizeof(struct dccp_hdr));
277 }
278
279 static inline unsigned int __dccp_basic_hdr_len(const struct dccp_hdr *dh)
280 {
281         return sizeof(*dh) + (dh->dccph_x ? sizeof(struct dccp_hdr_ext) : 0);
282 }
283
284 static inline unsigned int dccp_basic_hdr_len(const struct sk_buff *skb)
285 {
286         const struct dccp_hdr *dh = dccp_hdr(skb);
287         return __dccp_basic_hdr_len(dh);
288 }
289
290 static inline __u64 dccp_hdr_seq(const struct sk_buff *skb)
291 {
292         const struct dccp_hdr *dh = dccp_hdr(skb);
293         __u64 seq_nr =  ntohs(dh->dccph_seq);
294
295         if (dh->dccph_x != 0)
296                 seq_nr = (seq_nr << 32) + ntohl(dccp_hdrx(skb)->dccph_seq_low);
297         else
298                 seq_nr += (u32)dh->dccph_seq2 << 16;
299
300         return seq_nr;
301 }
302
303 static inline struct dccp_hdr_request *dccp_hdr_request(struct sk_buff *skb)
304 {
305         return (struct dccp_hdr_request *)(skb_transport_header(skb) +
306                                            dccp_basic_hdr_len(skb));
307 }
308
309 static inline struct dccp_hdr_ack_bits *dccp_hdr_ack_bits(const struct sk_buff *skb)
310 {
311         return (struct dccp_hdr_ack_bits *)(skb_transport_header(skb) +
312                                             dccp_basic_hdr_len(skb));
313 }
314
315 static inline u64 dccp_hdr_ack_seq(const struct sk_buff *skb)
316 {
317         const struct dccp_hdr_ack_bits *dhack = dccp_hdr_ack_bits(skb);
318         return ((u64)ntohs(dhack->dccph_ack_nr_high) << 32) + ntohl(dhack->dccph_ack_nr_low);
319 }
320
321 static inline struct dccp_hdr_response *dccp_hdr_response(struct sk_buff *skb)
322 {
323         return (struct dccp_hdr_response *)(skb_transport_header(skb) +
324                                             dccp_basic_hdr_len(skb));
325 }
326
327 static inline struct dccp_hdr_reset *dccp_hdr_reset(struct sk_buff *skb)
328 {
329         return (struct dccp_hdr_reset *)(skb_transport_header(skb) +
330                                          dccp_basic_hdr_len(skb));
331 }
332
333 static inline unsigned int __dccp_hdr_len(const struct dccp_hdr *dh)
334 {
335         return __dccp_basic_hdr_len(dh) +
336                dccp_packet_hdr_len(dh->dccph_type);
337 }
338
339 static inline unsigned int dccp_hdr_len(const struct sk_buff *skb)
340 {
341         return __dccp_hdr_len(dccp_hdr(skb));
342 }
343
344
345 /* initial values for each feature */
346 #define DCCPF_INITIAL_SEQUENCE_WINDOW           100
347 #define DCCPF_INITIAL_ACK_RATIO                 2
348 #define DCCPF_INITIAL_CCID                      DCCPC_CCID2
349 #define DCCPF_INITIAL_SEND_ACK_VECTOR           1
350 /* FIXME: for now we're default to 1 but it should really be 0 */
351 #define DCCPF_INITIAL_SEND_NDP_COUNT            1
352
353 #define DCCP_NDP_LIMIT 0xFFFFFF
354
355 /**
356   * struct dccp_minisock - Minimal DCCP connection representation
357   *
358   * Will be used to pass the state from dccp_request_sock to dccp_sock.
359   *
360   * @dccpms_sequence_window - Sequence Window Feature (section 7.5.2)
361   * @dccpms_ccid - Congestion Control Id (CCID) (section 10)
362   * @dccpms_send_ack_vector - Send Ack Vector Feature (section 11.5)
363   * @dccpms_send_ndp_count - Send NDP Count Feature (7.7.2)
364   * @dccpms_ack_ratio - Ack Ratio Feature (section 11.3)
365   * @dccpms_pending - List of features being negotiated
366   * @dccpms_conf -
367   */
368 struct dccp_minisock {
369         __u64                   dccpms_sequence_window;
370         __u8                    dccpms_rx_ccid;
371         __u8                    dccpms_tx_ccid;
372         __u8                    dccpms_send_ack_vector;
373         __u8                    dccpms_send_ndp_count;
374         __u8                    dccpms_ack_ratio;
375         struct list_head        dccpms_pending;
376         struct list_head        dccpms_conf;
377 };
378
379 struct dccp_opt_conf {
380         __u8                    *dccpoc_val;
381         __u8                    dccpoc_len;
382 };
383
384 struct dccp_opt_pend {
385         struct list_head        dccpop_node;
386         __u8                    dccpop_type;
387         __u8                    dccpop_feat;
388         __u8                    *dccpop_val;
389         __u8                    dccpop_len;
390         int                     dccpop_conf;
391         struct dccp_opt_conf    *dccpop_sc;
392 };
393
394 extern void dccp_minisock_init(struct dccp_minisock *dmsk);
395
396 extern int dccp_parse_options(struct sock *sk, struct sk_buff *skb);
397
398 struct dccp_request_sock {
399         struct inet_request_sock dreq_inet_rsk;
400         __u64                    dreq_iss;
401         __u64                    dreq_isr;
402         __be32                   dreq_service;
403 };
404
405 static inline struct dccp_request_sock *dccp_rsk(const struct request_sock *req)
406 {
407         return (struct dccp_request_sock *)req;
408 }
409
410 extern struct inet_timewait_death_row dccp_death_row;
411
412 struct dccp_options_received {
413         u32     dccpor_ndp; /* only 24 bits */
414         u32     dccpor_timestamp;
415         u32     dccpor_timestamp_echo;
416         u32     dccpor_elapsed_time;
417 };
418
419 struct ccid;
420
421 enum dccp_role {
422         DCCP_ROLE_UNDEFINED,
423         DCCP_ROLE_LISTEN,
424         DCCP_ROLE_CLIENT,
425         DCCP_ROLE_SERVER,
426 };
427
428 struct dccp_service_list {
429         __u32   dccpsl_nr;
430         __be32  dccpsl_list[0];
431 };
432
433 #define DCCP_SERVICE_INVALID_VALUE htonl((__u32)-1)
434 #define DCCP_SERVICE_CODE_IS_ABSENT             0
435
436 static inline int dccp_list_has_service(const struct dccp_service_list *sl,
437                                         const __be32 service)
438 {
439         if (likely(sl != NULL)) {
440                 u32 i = sl->dccpsl_nr;
441                 while (i--)
442                         if (sl->dccpsl_list[i] == service)
443                                 return 1;
444         }
445         return 0;
446 }
447
448 struct dccp_ackvec;
449
450 /**
451  * struct dccp_sock - DCCP socket state
452  *
453  * @dccps_swl - sequence number window low
454  * @dccps_swh - sequence number window high
455  * @dccps_awl - acknowledgement number window low
456  * @dccps_awh - acknowledgement number window high
457  * @dccps_iss - initial sequence number sent
458  * @dccps_isr - initial sequence number received
459  * @dccps_osr - first OPEN sequence number received
460  * @dccps_gss - greatest sequence number sent
461  * @dccps_gsr - greatest valid sequence number received
462  * @dccps_gar - greatest valid ack number received on a non-Sync; initialized to %dccps_iss
463  * @dccps_service - first (passive sock) or unique (active sock) service code
464  * @dccps_service_list - second .. last service code on passive socket
465  * @dccps_timestamp_time - time of latest TIMESTAMP option
466  * @dccps_timestamp_echo - latest timestamp received on a TIMESTAMP option
467  * @dccps_l_ack_ratio - feature-local Ack Ratio
468  * @dccps_r_ack_ratio - feature-remote Ack Ratio
469  * @dccps_pcslen - sender   partial checksum coverage (via sockopt)
470  * @dccps_pcrlen - receiver partial checksum coverage (via sockopt)
471  * @dccps_ndp_count - number of Non Data Packets since last data packet
472  * @dccps_mss_cache - current value of MSS (path MTU minus header sizes)
473  * @dccps_rate_last - timestamp for rate-limiting DCCP-Sync (RFC 4340, 7.5.4)
474  * @dccps_minisock - associated minisock (accessed via dccp_msk)
475  * @dccps_hc_rx_ackvec - rx half connection ack vector
476  * @dccps_hc_rx_ccid - CCID used for the receiver (or receiving half-connection)
477  * @dccps_hc_tx_ccid - CCID used for the sender (or sending half-connection)
478  * @dccps_options_received - parsed set of retrieved options
479  * @dccps_role - role of this sock, one of %dccp_role
480  * @dccps_hc_rx_insert_options - receiver wants to add options when acking
481  * @dccps_hc_tx_insert_options - sender wants to add options when sending
482  * @dccps_xmit_timer - timer for when CCID is not ready to send
483  * @dccps_syn_rtt - RTT sample from Request/Response exchange (in usecs)
484  */
485 struct dccp_sock {
486         /* inet_connection_sock has to be the first member of dccp_sock */
487         struct inet_connection_sock     dccps_inet_connection;
488 #define dccps_syn_rtt                   dccps_inet_connection.icsk_ack.lrcvtime
489         __u64                           dccps_swl;
490         __u64                           dccps_swh;
491         __u64                           dccps_awl;
492         __u64                           dccps_awh;
493         __u64                           dccps_iss;
494         __u64                           dccps_isr;
495         __u64                           dccps_osr;
496         __u64                           dccps_gss;
497         __u64                           dccps_gsr;
498         __u64                           dccps_gar;
499         __be32                          dccps_service;
500         struct dccp_service_list        *dccps_service_list;
501         ktime_t                         dccps_timestamp_time;
502         __u32                           dccps_timestamp_echo;
503         __u16                           dccps_l_ack_ratio;
504         __u16                           dccps_r_ack_ratio;
505         __u16                           dccps_pcslen;
506         __u16                           dccps_pcrlen;
507         unsigned long                   dccps_ndp_count;
508         __u32                           dccps_mss_cache;
509         unsigned long                   dccps_rate_last;
510         struct dccp_minisock            dccps_minisock;
511         struct dccp_ackvec              *dccps_hc_rx_ackvec;
512         struct ccid                     *dccps_hc_rx_ccid;
513         struct ccid                     *dccps_hc_tx_ccid;
514         struct dccp_options_received    dccps_options_received;
515         enum dccp_role                  dccps_role:2;
516         __u8                            dccps_hc_rx_insert_options:1;
517         __u8                            dccps_hc_tx_insert_options:1;
518         struct timer_list               dccps_xmit_timer;
519 };
520
521 static inline struct dccp_sock *dccp_sk(const struct sock *sk)
522 {
523         return (struct dccp_sock *)sk;
524 }
525
526 static inline struct dccp_minisock *dccp_msk(const struct sock *sk)
527 {
528         return (struct dccp_minisock *)&dccp_sk(sk)->dccps_minisock;
529 }
530
531 static inline const char *dccp_role(const struct sock *sk)
532 {
533         switch (dccp_sk(sk)->dccps_role) {
534         case DCCP_ROLE_UNDEFINED: return "undefined";
535         case DCCP_ROLE_LISTEN:    return "listen";
536         case DCCP_ROLE_SERVER:    return "server";
537         case DCCP_ROLE_CLIENT:    return "client";
538         }
539         return NULL;
540 }
541
542 #endif /* __KERNEL__ */
543
544 #endif /* _LINUX_DCCP_H */