[DCCP]: Combine allocating & zeroing header space on skb
[linux-2.6.git] / 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         __u16   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 - Conection initiation request header
60  *
61  * @dccph_req_service - Service to which the client app wants to connect
62  * @dccph_req_options - list of options (must be a multiple of 32 bits
63  */
64 struct dccp_hdr_request {
65         __be32  dccph_req_service;
66 };
67 /**
68  * struct dccp_hdr_ack_bits - acknowledgment bits common to most packets
69  *
70  * @dccph_resp_ack_nr_high - 48 bit ack number high order bits, contains GSR
71  * @dccph_resp_ack_nr_low - 48 bit ack number low order bits, contains GSR
72  */
73 struct dccp_hdr_ack_bits {
74         __be16  dccph_reserved1;
75         __be16  dccph_ack_nr_high;
76         __be32  dccph_ack_nr_low;
77 };
78 /**
79  * struct dccp_hdr_response - Conection initiation response header
80  *
81  * @dccph_resp_ack_nr_high - 48 bit ack number high order bits, contains GSR
82  * @dccph_resp_ack_nr_low - 48 bit ack number low order bits, contains GSR
83  * @dccph_resp_service - Echoes the Service Code on a received DCCP-Request
84  * @dccph_resp_options - list of options (must be a multiple of 32 bits
85  */
86 struct dccp_hdr_response {
87         struct dccp_hdr_ack_bits        dccph_resp_ack;
88         __be32                          dccph_resp_service;
89 };
90
91 /**
92  * struct dccp_hdr_reset - Unconditionally shut down a connection
93  *
94  * @dccph_reset_service - Echoes the Service Code on a received DCCP-Request
95  * @dccph_reset_options - list of options (must be a multiple of 32 bits
96  */
97 struct dccp_hdr_reset {
98         struct dccp_hdr_ack_bits        dccph_reset_ack;
99         __u8                            dccph_reset_code,
100                                         dccph_reset_data[3];
101 };
102
103 enum dccp_pkt_type {
104         DCCP_PKT_REQUEST = 0,
105         DCCP_PKT_RESPONSE,
106         DCCP_PKT_DATA,
107         DCCP_PKT_ACK,
108         DCCP_PKT_DATAACK,
109         DCCP_PKT_CLOSEREQ,
110         DCCP_PKT_CLOSE,
111         DCCP_PKT_RESET,
112         DCCP_PKT_SYNC,
113         DCCP_PKT_SYNCACK,
114         DCCP_PKT_INVALID,
115 };
116
117 #define DCCP_NR_PKT_TYPES DCCP_PKT_INVALID
118
119 static inline unsigned int dccp_packet_hdr_len(const __u8 type)
120 {
121         if (type == DCCP_PKT_DATA)
122                 return 0;
123         if (type == DCCP_PKT_DATAACK    ||
124             type == DCCP_PKT_ACK        ||
125             type == DCCP_PKT_SYNC       ||
126             type == DCCP_PKT_SYNCACK    ||
127             type == DCCP_PKT_CLOSE      ||
128             type == DCCP_PKT_CLOSEREQ)
129                 return sizeof(struct dccp_hdr_ack_bits);
130         if (type == DCCP_PKT_REQUEST)
131                 return sizeof(struct dccp_hdr_request);
132         if (type == DCCP_PKT_RESPONSE)
133                 return sizeof(struct dccp_hdr_response);
134         return sizeof(struct dccp_hdr_reset);
135 }
136 enum dccp_reset_codes {
137         DCCP_RESET_CODE_UNSPECIFIED = 0,
138         DCCP_RESET_CODE_CLOSED,
139         DCCP_RESET_CODE_ABORTED,
140         DCCP_RESET_CODE_NO_CONNECTION,
141         DCCP_RESET_CODE_PACKET_ERROR,
142         DCCP_RESET_CODE_OPTION_ERROR,
143         DCCP_RESET_CODE_MANDATORY_ERROR,
144         DCCP_RESET_CODE_CONNECTION_REFUSED,
145         DCCP_RESET_CODE_BAD_SERVICE_CODE,
146         DCCP_RESET_CODE_TOO_BUSY,
147         DCCP_RESET_CODE_BAD_INIT_COOKIE,
148         DCCP_RESET_CODE_AGGRESSION_PENALTY,
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_CCID_SPECIFIC = 128,
169         DCCPO_MAX_CCID_SPECIFIC = 255,
170 };
171
172 /* DCCP CCIDS */
173 enum {
174         DCCPC_CCID2 = 2,
175         DCCPC_CCID3 = 3,
176 };
177
178 /* DCCP features */
179 enum {
180         DCCPF_RESERVED = 0,
181         DCCPF_CCID = 1,
182         DCCPF_SEQUENCE_WINDOW = 3,
183         DCCPF_ACK_RATIO = 5,
184         DCCPF_SEND_ACK_VECTOR = 6,
185         DCCPF_SEND_NDP_COUNT = 7,
186         /* 10-127 reserved */
187         DCCPF_MIN_CCID_SPECIFIC = 128,
188         DCCPF_MAX_CCID_SPECIFIC = 255,
189 };
190
191 /* this structure is argument to DCCP_SOCKOPT_CHANGE_X */
192 struct dccp_so_feat {
193         __u8 dccpsf_feat;
194         __u8 __user *dccpsf_val;
195         __u8 dccpsf_len;
196 };
197
198 /* DCCP socket options */
199 #define DCCP_SOCKOPT_PACKET_SIZE        1
200 #define DCCP_SOCKOPT_SERVICE            2
201 #define DCCP_SOCKOPT_CHANGE_L           3
202 #define DCCP_SOCKOPT_CHANGE_R           4
203 #define DCCP_SOCKOPT_CCID_RX_INFO       128
204 #define DCCP_SOCKOPT_CCID_TX_INFO       192
205
206 #define DCCP_SERVICE_LIST_MAX_LEN      32
207
208 #ifdef __KERNEL__
209
210 #include <linux/in.h>
211 #include <linux/list.h>
212 #include <linux/uio.h>
213 #include <linux/workqueue.h>
214
215 #include <net/inet_connection_sock.h>
216 #include <net/inet_sock.h>
217 #include <net/inet_timewait_sock.h>
218 #include <net/tcp_states.h>
219
220 enum dccp_state {
221         DCCP_OPEN       = TCP_ESTABLISHED,
222         DCCP_REQUESTING = TCP_SYN_SENT,
223         DCCP_PARTOPEN   = TCP_FIN_WAIT1, /* FIXME:
224                                             This mapping is horrible, but TCP has
225                                             no matching state for DCCP_PARTOPEN,
226                                             as TCP_SYN_RECV is already used by
227                                             DCCP_RESPOND, why don't stop using TCP
228                                             mapping of states? OK, now we don't use
229                                             sk_stream_sendmsg anymore, so doesn't
230                                             seem to exist any reason for us to
231                                             do the TCP mapping here */
232         DCCP_LISTEN     = TCP_LISTEN,
233         DCCP_RESPOND    = TCP_SYN_RECV,
234         DCCP_CLOSING    = TCP_CLOSING,
235         DCCP_TIME_WAIT  = TCP_TIME_WAIT,
236         DCCP_CLOSED     = TCP_CLOSE,
237         DCCP_MAX_STATES = TCP_MAX_STATES,
238 };
239
240 #define DCCP_STATE_MASK 0xf
241 #define DCCP_ACTION_FIN (1<<7)
242
243 enum {
244         DCCPF_OPEN       = TCPF_ESTABLISHED,
245         DCCPF_REQUESTING = TCPF_SYN_SENT,
246         DCCPF_PARTOPEN   = TCPF_FIN_WAIT1,
247         DCCPF_LISTEN     = TCPF_LISTEN,
248         DCCPF_RESPOND    = TCPF_SYN_RECV,
249         DCCPF_CLOSING    = TCPF_CLOSING,
250         DCCPF_TIME_WAIT  = TCPF_TIME_WAIT,
251         DCCPF_CLOSED     = TCPF_CLOSE,
252 };
253
254 static inline struct dccp_hdr *dccp_hdr(const struct sk_buff *skb)
255 {
256         return (struct dccp_hdr *)skb->h.raw;
257 }
258
259 static inline struct dccp_hdr *dccp_zeroed_hdr(struct sk_buff *skb, int headlen)
260 {
261         skb->h.raw = skb_push(skb, headlen);
262         memset(skb->h.raw, 0, headlen);
263         return dccp_hdr(skb);
264 }
265
266 static inline struct dccp_hdr_ext *dccp_hdrx(const struct sk_buff *skb)
267 {
268         return (struct dccp_hdr_ext *)(skb->h.raw + sizeof(struct dccp_hdr));
269 }
270
271 static inline unsigned int __dccp_basic_hdr_len(const struct dccp_hdr *dh)
272 {
273         return sizeof(*dh) + (dh->dccph_x ? sizeof(struct dccp_hdr_ext) : 0);
274 }
275
276 static inline unsigned int dccp_basic_hdr_len(const struct sk_buff *skb)
277 {
278         const struct dccp_hdr *dh = dccp_hdr(skb);
279         return __dccp_basic_hdr_len(dh);
280 }
281
282 static inline __u64 dccp_hdr_seq(const struct sk_buff *skb)
283 {
284         const struct dccp_hdr *dh = dccp_hdr(skb);
285         __u64 seq_nr =  ntohs(dh->dccph_seq);
286
287         if (dh->dccph_x != 0)
288                 seq_nr = (seq_nr << 32) + ntohl(dccp_hdrx(skb)->dccph_seq_low);
289         else
290                 seq_nr += (u32)dh->dccph_seq2 << 16;
291
292         return seq_nr;
293 }
294
295 static inline struct dccp_hdr_request *dccp_hdr_request(struct sk_buff *skb)
296 {
297         return (struct dccp_hdr_request *)(skb->h.raw + dccp_basic_hdr_len(skb));
298 }
299
300 static inline struct dccp_hdr_ack_bits *dccp_hdr_ack_bits(const struct sk_buff *skb)
301 {
302         return (struct dccp_hdr_ack_bits *)(skb->h.raw + dccp_basic_hdr_len(skb));
303 }
304
305 static inline u64 dccp_hdr_ack_seq(const struct sk_buff *skb)
306 {
307         const struct dccp_hdr_ack_bits *dhack = dccp_hdr_ack_bits(skb);
308         return ((u64)ntohs(dhack->dccph_ack_nr_high) << 32) + ntohl(dhack->dccph_ack_nr_low);
309 }
310
311 static inline struct dccp_hdr_response *dccp_hdr_response(struct sk_buff *skb)
312 {
313         return (struct dccp_hdr_response *)(skb->h.raw + dccp_basic_hdr_len(skb));
314 }
315
316 static inline struct dccp_hdr_reset *dccp_hdr_reset(struct sk_buff *skb)
317 {
318         return (struct dccp_hdr_reset *)(skb->h.raw + dccp_basic_hdr_len(skb));
319 }
320
321 static inline unsigned int __dccp_hdr_len(const struct dccp_hdr *dh)
322 {
323         return __dccp_basic_hdr_len(dh) +
324                dccp_packet_hdr_len(dh->dccph_type);
325 }
326
327 static inline unsigned int dccp_hdr_len(const struct sk_buff *skb)
328 {
329         return __dccp_hdr_len(dccp_hdr(skb));
330 }
331
332
333 /* initial values for each feature */
334 #define DCCPF_INITIAL_SEQUENCE_WINDOW           100
335 #define DCCPF_INITIAL_ACK_RATIO                 2
336 #define DCCPF_INITIAL_CCID                      DCCPC_CCID2
337 #define DCCPF_INITIAL_SEND_ACK_VECTOR           1
338 /* FIXME: for now we're default to 1 but it should really be 0 */
339 #define DCCPF_INITIAL_SEND_NDP_COUNT            1
340
341 #define DCCP_NDP_LIMIT 0xFFFFFF
342
343 /**
344   * struct dccp_minisock - Minimal DCCP connection representation
345   *
346   * Will be used to pass the state from dccp_request_sock to dccp_sock.
347   *
348   * @dccpms_sequence_window - Sequence Window Feature (section 7.5.2)
349   * @dccpms_ccid - Congestion Control Id (CCID) (section 10)
350   * @dccpms_send_ack_vector - Send Ack Vector Feature (section 11.5)
351   * @dccpms_send_ndp_count - Send NDP Count Feature (7.7.2)
352   */
353 struct dccp_minisock {
354         __u64                   dccpms_sequence_window;
355         __u8                    dccpms_rx_ccid;
356         __u8                    dccpms_tx_ccid;
357         __u8                    dccpms_send_ack_vector;
358         __u8                    dccpms_send_ndp_count;
359         __u8                    dccpms_ack_ratio;
360         struct list_head        dccpms_pending;
361         struct list_head        dccpms_conf;
362 };
363
364 struct dccp_opt_conf {
365         __u8                    *dccpoc_val;
366         __u8                    dccpoc_len;
367 };
368
369 struct dccp_opt_pend {
370         struct list_head        dccpop_node;
371         __u8                    dccpop_type;
372         __u8                    dccpop_feat;
373         __u8                    *dccpop_val;
374         __u8                    dccpop_len;
375         int                     dccpop_conf;
376         struct dccp_opt_conf    *dccpop_sc;
377 };
378
379 extern void __dccp_minisock_init(struct dccp_minisock *dmsk);
380 extern void dccp_minisock_init(struct dccp_minisock *dmsk);
381
382 extern int dccp_parse_options(struct sock *sk, struct sk_buff *skb);
383
384 struct dccp_request_sock {
385         struct inet_request_sock dreq_inet_rsk;
386         __u64                    dreq_iss;
387         __u64                    dreq_isr;
388         __be32                   dreq_service;
389 };
390
391 static inline struct dccp_request_sock *dccp_rsk(const struct request_sock *req)
392 {
393         return (struct dccp_request_sock *)req;
394 }
395
396 extern struct inet_timewait_death_row dccp_death_row;
397
398 struct dccp_options_received {
399         u32     dccpor_ndp; /* only 24 bits */
400         u32     dccpor_timestamp;
401         u32     dccpor_timestamp_echo;
402         u32     dccpor_elapsed_time;
403 };
404
405 struct ccid;
406
407 enum dccp_role {
408         DCCP_ROLE_UNDEFINED,
409         DCCP_ROLE_LISTEN,
410         DCCP_ROLE_CLIENT,
411         DCCP_ROLE_SERVER,
412 };
413
414 struct dccp_service_list {
415         __u32   dccpsl_nr;
416         __be32  dccpsl_list[0];
417 };
418
419 #define DCCP_SERVICE_INVALID_VALUE htonl((__u32)-1)
420 #define DCCP_SERVICE_CODE_IS_ABSENT              0
421
422 static inline int dccp_list_has_service(const struct dccp_service_list *sl,
423                                         const __be32 service)
424 {
425         if (likely(sl != NULL)) {
426                 u32 i = sl->dccpsl_nr;
427                 while (i--)
428                         if (sl->dccpsl_list[i] == service)
429                                 return 1; 
430         }
431         return 0;
432 }
433
434 struct dccp_ackvec;
435
436 /**
437  * struct dccp_sock - DCCP socket state
438  *
439  * @dccps_swl - sequence number window low
440  * @dccps_swh - sequence number window high
441  * @dccps_awl - acknowledgement number window low
442  * @dccps_awh - acknowledgement number window high
443  * @dccps_iss - initial sequence number sent
444  * @dccps_isr - initial sequence number received
445  * @dccps_osr - first OPEN sequence number received
446  * @dccps_gss - greatest sequence number sent
447  * @dccps_gsr - greatest valid sequence number received
448  * @dccps_gar - greatest valid ack number received on a non-Sync; initialized to %dccps_iss
449  * @dccps_timestamp_time - time of latest TIMESTAMP option
450  * @dccps_timestamp_echo - latest timestamp received on a TIMESTAMP option
451  * @dccps_packet_size - Set thru setsockopt
452  * @dccps_role - Role of this sock, one of %dccp_role
453  * @dccps_ndp_count - number of Non Data Packets since last data packet
454  * @dccps_hc_rx_ackvec - rx half connection ack vector
455  * @dccps_xmit_timer - timer for when CCID is not ready to send
456  */
457 struct dccp_sock {
458         /* inet_connection_sock has to be the first member of dccp_sock */
459         struct inet_connection_sock     dccps_inet_connection;
460         __u64                           dccps_swl;
461         __u64                           dccps_swh;
462         __u64                           dccps_awl;
463         __u64                           dccps_awh;
464         __u64                           dccps_iss;
465         __u64                           dccps_isr;
466         __u64                           dccps_osr;
467         __u64                           dccps_gss;
468         __u64                           dccps_gsr;
469         __u64                           dccps_gar;
470         __be32                          dccps_service;
471         struct dccp_service_list        *dccps_service_list;
472         struct timeval                  dccps_timestamp_time;
473         __u32                           dccps_timestamp_echo;
474         __u32                           dccps_packet_size;
475         __u16                           dccps_l_ack_ratio;
476         __u16                           dccps_r_ack_ratio;
477         unsigned long                   dccps_ndp_count;
478         __u32                           dccps_mss_cache;
479         struct dccp_minisock            dccps_minisock;
480         struct dccp_ackvec              *dccps_hc_rx_ackvec;
481         struct ccid                     *dccps_hc_rx_ccid;
482         struct ccid                     *dccps_hc_tx_ccid;
483         struct dccp_options_received    dccps_options_received;
484         struct timeval                  dccps_epoch;
485         enum dccp_role                  dccps_role:2;
486         __u8                            dccps_hc_rx_insert_options:1;
487         __u8                            dccps_hc_tx_insert_options:1;
488         struct timer_list               dccps_xmit_timer;
489 };
490  
491 static inline struct dccp_sock *dccp_sk(const struct sock *sk)
492 {
493         return (struct dccp_sock *)sk;
494 }
495
496 static inline struct dccp_minisock *dccp_msk(const struct sock *sk)
497 {
498         return (struct dccp_minisock *)&dccp_sk(sk)->dccps_minisock;
499 }
500
501 static inline const char *dccp_role(const struct sock *sk)
502 {
503         switch (dccp_sk(sk)->dccps_role) {
504         case DCCP_ROLE_UNDEFINED: return "undefined";
505         case DCCP_ROLE_LISTEN:    return "listen";
506         case DCCP_ROLE_SERVER:    return "server";
507         case DCCP_ROLE_CLIENT:    return "client";
508         }
509         return NULL;
510 }
511
512 #endif /* __KERNEL__ */
513
514 #endif /* _LINUX_DCCP_H */