[DCCP]: Initial implementation
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / net / dccp / dccp.h
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ACM
1#ifndef _DCCP_H
2#define _DCCP_H
3/*
4 * net/dccp/dccp.h
5 *
6 * An implementation of the DCCP protocol
7 * Arnaldo Carvalho de Melo <acme@conectiva.com.br>
8 *
9 * This program is free software; you can redistribute it and/or modify it
10 * under the terms of the GNU General Public License version 2 as
11 * published by the Free Software Foundation.
12 */
13
14#include <linux/dccp.h>
15#include <net/snmp.h>
16#include <net/sock.h>
17#include <net/tcp.h>
18
19#define DCCP_DEBUG
20
21#ifdef DCCP_DEBUG
22extern int dccp_debug;
23
24#define dccp_pr_debug(format, a...) \
25 do { if (dccp_debug) \
26 printk(KERN_DEBUG "%s: " format, __FUNCTION__ , ##a); \
27 } while (0)
28#define dccp_pr_debug_cat(format, a...) do { if (dccp_debug) printk(format, ##a); } while (0)
29#else
30#define dccp_pr_debug(format, a...)
31#define dccp_pr_debug_cat(format, a...)
32#endif
33
34extern struct inet_hashinfo dccp_hashinfo;
35
36extern atomic_t dccp_orphan_count;
37extern int dccp_tw_count;
38extern void dccp_tw_deschedule(struct inet_timewait_sock *tw);
39
40extern void dccp_time_wait(struct sock *sk, int state, int timeo);
41
42/* FIXME: Right size this */
43#define DCCP_MAX_OPT_LEN 128
44
45#define DCCP_MAX_PACKET_HDR 32
46
47#define MAX_DCCP_HEADER (DCCP_MAX_PACKET_HDR + DCCP_MAX_OPT_LEN + MAX_HEADER)
48
49#define DCCP_TIMEWAIT_LEN (60 * HZ) /* how long to wait to destroy TIME-WAIT
50 * state, about 60 seconds */
51
52/* draft-ietf-dccp-spec-11.txt initial RTO value */
53#define DCCP_TIMEOUT_INIT ((unsigned)(3 * HZ))
54
55/* Maximal interval between probes for local resources. */
56#define DCCP_RESOURCE_PROBE_INTERVAL ((unsigned)(HZ / 2U))
57
58#define DCCP_RTO_MAX ((unsigned)(120 * HZ)) /* FIXME: using TCP value */
59
60extern struct proto dccp_v4_prot;
61
62/* is seq1 < seq2 ? */
63static inline const int before48(const u64 seq1, const u64 seq2)
64{
65 return (const s64)((seq1 << 16) - (seq2 << 16)) < 0;
66}
67
68/* is seq1 > seq2 ? */
69static inline const int after48(const u64 seq1, const u64 seq2)
70{
71 return (const s64)((seq2 << 16) - (seq1 << 16)) < 0;
72}
73
74/* is seq2 <= seq1 <= seq3 ? */
75static inline const int between48(const u64 seq1, const u64 seq2, const u64 seq3)
76{
77 return (seq3 << 16) - (seq2 << 16) >= (seq1 << 16) - (seq2 << 16);
78}
79
80static inline u64 max48(const u64 seq1, const u64 seq2)
81{
82 return after48(seq1, seq2) ? seq1 : seq2;
83}
84
85enum {
86 DCCP_MIB_NUM = 0,
87 DCCP_MIB_ACTIVEOPENS, /* ActiveOpens */
88 DCCP_MIB_ESTABRESETS, /* EstabResets */
89 DCCP_MIB_CURRESTAB, /* CurrEstab */
90 DCCP_MIB_OUTSEGS, /* OutSegs */
91 DCCP_MIB_OUTRSTS,
92 DCCP_MIB_ABORTONTIMEOUT,
93 DCCP_MIB_TIMEOUTS,
94 DCCP_MIB_ABORTFAILED,
95 DCCP_MIB_PASSIVEOPENS,
96 DCCP_MIB_ATTEMPTFAILS,
97 DCCP_MIB_OUTDATAGRAMS,
98 DCCP_MIB_INERRS,
99 DCCP_MIB_OPTMANDATORYERROR,
100 DCCP_MIB_INVALIDOPT,
101 __DCCP_MIB_MAX
102};
103
104#define DCCP_MIB_MAX __DCCP_MIB_MAX
105struct dccp_mib {
106 unsigned long mibs[DCCP_MIB_MAX];
107} __SNMP_MIB_ALIGN__;
108
109DECLARE_SNMP_STAT(struct dccp_mib, dccp_statistics);
110#define DCCP_INC_STATS(field) SNMP_INC_STATS(dccp_statistics, field)
111#define DCCP_INC_STATS_BH(field) SNMP_INC_STATS_BH(dccp_statistics, field)
112#define DCCP_INC_STATS_USER(field) SNMP_INC_STATS_USER(dccp_statistics, field)
113#define DCCP_DEC_STATS(field) SNMP_DEC_STATS(dccp_statistics, field)
114#define DCCP_ADD_STATS_BH(field, val) SNMP_ADD_STATS_BH(dccp_statistics, field, val)
115#define DCCP_ADD_STATS_USER(field, val) SNMP_ADD_STATS_USER(dccp_statistics, field, val)
116
117extern int dccp_transmit_skb(struct sock *sk, struct sk_buff *skb);
118extern int dccp_retransmit_skb(struct sock *sk, struct sk_buff *skb);
119
120extern int dccp_send_response(struct sock *sk);
121extern void dccp_send_ack(struct sock *sk);
122extern void dccp_send_delayed_ack(struct sock *sk);
123extern void dccp_send_sync(struct sock *sk, u64 seq);
124
125extern void dccp_init_xmit_timers(struct sock *sk);
126static inline void dccp_clear_xmit_timers(struct sock *sk)
127{
128 inet_csk_clear_xmit_timers(sk);
129}
130
131extern unsigned int dccp_sync_mss(struct sock *sk, u32 pmtu);
132
133extern const char *dccp_packet_name(const int type);
134extern const char *dccp_state_name(const int state);
135
136static inline void dccp_set_state(struct sock *sk, const int state)
137{
138 const int oldstate = sk->sk_state;
139
140 dccp_pr_debug("%s(%p) %-10.10s -> %s\n",
141 dccp_role(sk), sk,
142 dccp_state_name(oldstate), dccp_state_name(state));
143 WARN_ON(state == oldstate);
144
145 switch (state) {
146 case DCCP_OPEN:
147 if (oldstate != DCCP_OPEN)
148 DCCP_INC_STATS(DCCP_MIB_CURRESTAB);
149 break;
150
151 case DCCP_CLOSED:
152 if (oldstate == DCCP_CLOSING || oldstate == DCCP_OPEN)
153 DCCP_INC_STATS(DCCP_MIB_ESTABRESETS);
154
155 sk->sk_prot->unhash(sk);
156 if (inet_csk(sk)->icsk_bind_hash != NULL &&
157 !(sk->sk_userlocks & SOCK_BINDPORT_LOCK))
158 inet_put_port(&dccp_hashinfo, sk);
159 /* fall through */
160 default:
161 if (oldstate == DCCP_OPEN)
162 DCCP_DEC_STATS(DCCP_MIB_CURRESTAB);
163 }
164
165 /* Change state AFTER socket is unhashed to avoid closed
166 * socket sitting in hash tables.
167 */
168 sk->sk_state = state;
169}
170
171static inline void dccp_done(struct sock *sk)
172{
173 dccp_set_state(sk, DCCP_CLOSED);
174 dccp_clear_xmit_timers(sk);
175
176 sk->sk_shutdown = SHUTDOWN_MASK;
177
178 if (!sock_flag(sk, SOCK_DEAD))
179 sk->sk_state_change(sk);
180 else
181 inet_csk_destroy_sock(sk);
182}
183
184static inline void dccp_openreq_init(struct request_sock *req,
185 struct dccp_sock *dp,
186 struct sk_buff *skb)
187{
188 /*
189 * FIXME: fill in the other req fields from the DCCP options
190 * received
191 */
192 inet_rsk(req)->rmt_port = dccp_hdr(skb)->dccph_sport;
193 inet_rsk(req)->acked = 0;
194 req->rcv_wnd = 0;
195}
196
197extern void dccp_v4_send_check(struct sock *sk, struct dccp_hdr *dh, int len,
198 struct sk_buff *skb);
199extern int dccp_v4_conn_request(struct sock *sk, struct sk_buff *skb);
200
201extern struct sock *dccp_create_openreq_child(struct sock *sk,
202 const struct request_sock *req,
203 const struct sk_buff *skb);
204
205extern int dccp_v4_do_rcv(struct sock *sk, struct sk_buff *skb);
206
207extern void dccp_v4_err(struct sk_buff *skb, u32);
208
209extern int dccp_v4_rcv(struct sk_buff *skb);
210
211extern struct sock *dccp_v4_request_recv_sock(struct sock *sk,
212 struct sk_buff *skb,
213 struct request_sock *req,
214 struct dst_entry *dst);
215extern struct sock *dccp_check_req(struct sock *sk, struct sk_buff *skb,
216 struct request_sock *req,
217 struct request_sock **prev);
218
219extern int dccp_child_process(struct sock *parent, struct sock *child,
220 struct sk_buff *skb);
221extern int dccp_rcv_state_process(struct sock *sk, struct sk_buff *skb,
222 struct dccp_hdr *dh, unsigned len);
223extern int dccp_rcv_established(struct sock *sk, struct sk_buff *skb,
224 const struct dccp_hdr *dh, const unsigned len);
225
226extern void dccp_close(struct sock *sk, long timeout);
227extern struct sk_buff *dccp_make_response(struct sock *sk,
228 struct dst_entry *dst,
229 struct request_sock *req);
230
231extern int dccp_connect(struct sock *sk);
232extern int dccp_disconnect(struct sock *sk, int flags);
233extern int dccp_getsockopt(struct sock *sk, int level, int optname,
234 char *optval, int *optlen);
235extern int dccp_ioctl(struct sock *sk, int cmd, unsigned long arg);
236extern int dccp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
237 size_t size);
238extern int dccp_recvmsg(struct kiocb *iocb, struct sock *sk,
239 struct msghdr *msg, size_t len, int nonblock,
240 int flags, int *addr_len);
241extern int dccp_setsockopt(struct sock *sk, int level, int optname,
242 char *optval, int optlen);
243extern void dccp_shutdown(struct sock *sk, int how);
244
245extern int dccp_v4_checksum(struct sk_buff *skb);
246
247extern int dccp_v4_send_reset(struct sock *sk, enum dccp_reset_codes code);
248extern void dccp_send_close(struct sock *sk);
249
250struct dccp_skb_cb {
251 __u8 dccpd_type;
252 __u8 dccpd_reset_code;
253 __u8 dccpd_service;
254 __u8 dccpd_ccval;
255 __u64 dccpd_seq;
256 __u64 dccpd_ack_seq;
257 int dccpd_opt_len;
258};
259
260#define DCCP_SKB_CB(__skb) ((struct dccp_skb_cb *)&((__skb)->cb[0]))
261
262static inline int dccp_non_data_packet(const struct sk_buff *skb)
263{
264 const __u8 type = DCCP_SKB_CB(skb)->dccpd_type;
265
266 return type == DCCP_PKT_ACK ||
267 type == DCCP_PKT_CLOSE ||
268 type == DCCP_PKT_CLOSEREQ ||
269 type == DCCP_PKT_RESET ||
270 type == DCCP_PKT_SYNC ||
271 type == DCCP_PKT_SYNCACK;
272}
273
274static inline int dccp_packet_without_ack(const struct sk_buff *skb)
275{
276 const __u8 type = DCCP_SKB_CB(skb)->dccpd_type;
277
278 return type == DCCP_PKT_DATA || type == DCCP_PKT_REQUEST;
279}
280
281#define DCCP_MAX_SEQNO ((((u64)1) << 48) - 1)
282#define DCCP_PKT_WITHOUT_ACK_SEQ (DCCP_MAX_SEQNO << 2)
283
284static inline void dccp_set_seqno(u64 *seqno, u64 value)
285{
286 if (value > DCCP_MAX_SEQNO)
287 value -= DCCP_MAX_SEQNO + 1;
288 *seqno = value;
289}
290
291static inline u64 dccp_delta_seqno(u64 seqno1, u64 seqno2)
292{
293 return ((seqno2 << 16) - (seqno1 << 16)) >> 16;
294}
295
296static inline void dccp_inc_seqno(u64 *seqno)
297{
298 if (++*seqno > DCCP_MAX_SEQNO)
299 *seqno = 0;
300}
301
302static inline void dccp_hdr_set_seq(struct dccp_hdr *dh, const u64 gss)
303{
304 struct dccp_hdr_ext *dhx = (struct dccp_hdr_ext *)((void *)dh + sizeof(*dh));
305
306#if defined(__LITTLE_ENDIAN_BITFIELD)
307 dh->dccph_seq = htonl((gss >> 32)) >> 8;
308#elif defined(__BIG_ENDIAN_BITFIELD)
309 dh->dccph_seq = htonl((gss >> 32));
310#else
311#error "Adjust your <asm/byteorder.h> defines"
312#endif
313 dhx->dccph_seq_low = htonl(gss & 0xffffffff);
314}
315
316static inline void dccp_hdr_set_ack(struct dccp_hdr_ack_bits *dhack, const u64 gsr)
317{
318#if defined(__LITTLE_ENDIAN_BITFIELD)
319 dhack->dccph_ack_nr_high = htonl((gsr >> 32)) >> 8;
320#elif defined(__BIG_ENDIAN_BITFIELD)
321 dhack->dccph_ack_nr_high = htonl((gsr >> 32));
322#else
323#error "Adjust your <asm/byteorder.h> defines"
324#endif
325 dhack->dccph_ack_nr_low = htonl(gsr & 0xffffffff);
326}
327
328static inline void dccp_update_gsr(struct sock *sk, u64 seq)
329{
330 struct dccp_sock *dp = dccp_sk(sk);
331 u64 tmp_gsr;
332
333 dccp_set_seqno(&tmp_gsr, dp->dccps_gsr + 1 - (dp->dccps_options.dccpo_sequence_window / 4));
334 dp->dccps_gsr = seq;
335 dccp_set_seqno(&dp->dccps_swl, max48(tmp_gsr, dp->dccps_isr));
336 dccp_set_seqno(&dp->dccps_swh,
337 dp->dccps_gsr + (3 * dp->dccps_options.dccpo_sequence_window) / 4);
338}
339
340static inline void dccp_update_gss(struct sock *sk, u64 seq)
341{
342 struct dccp_sock *dp = dccp_sk(sk);
343 u64 tmp_gss;
344
345 dccp_set_seqno(&tmp_gss, dp->dccps_gss - dp->dccps_options.dccpo_sequence_window + 1);
346 dp->dccps_awl = max48(tmp_gss, dp->dccps_iss);
347 dp->dccps_awh = dp->dccps_gss = seq;
348}
349
350extern void dccp_insert_options(struct sock *sk, struct sk_buff *skb);
351extern void dccp_insert_option_elapsed_time(struct sock *sk,
352 struct sk_buff *skb,
353 u32 elapsed_time);
354extern void dccp_insert_option(struct sock *sk, struct sk_buff *skb,
355 unsigned char option,
356 const void *value, unsigned char len);
357
358extern struct socket *dccp_ctl_socket;
359
360#define DCCP_ACKPKTS_STATE_RECEIVED 0
361#define DCCP_ACKPKTS_STATE_ECN_MARKED (1 << 6)
362#define DCCP_ACKPKTS_STATE_NOT_RECEIVED (3 << 6)
363
364#define DCCP_ACKPKTS_STATE_MASK 0xC0 /* 11000000 */
365#define DCCP_ACKPKTS_LEN_MASK 0x3F /* 00111111 */
366
367/** struct dccp_ackpkts - acknowledgeable packets
368 *
369 * This data structure is the one defined in the DCCP draft
370 * Appendix A.
371 *
372 * @dccpap_buf_head - circular buffer head
373 * @dccpap_buf_tail - circular buffer tail
374 * @dccpap_buf_ackno - ack # of the most recent packet acknoldgeable in the buffer (i.e. %dccpap_buf_head)
375 * @dccpap_buf_nonce - the one-bit sum of the ECN Nonces on all packets acked by the buffer with State 0
376 *
377 * Additionally, the HC-Receiver must keep some information about the
378 * Ack Vectors it has recently sent. For each packet sent carrying an
379 * Ack Vector, it remembers four variables:
380 *
381 * @dccpap_ack_seqno - the Sequence Number used for the packet (HC-Receiver seqno)
382 * @dccpap_ack_ptr - the value of buf_head at the time of acknowledgement.
383 * @dccpap_ack_ackno - the Acknowledgement Number used for the packet (HC-Sender seqno)
384 * @dccpap_ack_nonce - the one-bit sum of the ECN Nonces for all State 0.
385 *
386 * @dccpap_buf_len - circular buffer length
387 * @dccpap_buf - circular buffer of acknowledgeable packets
388 */
389struct dccp_ackpkts {
390 unsigned int dccpap_buf_head;
391 unsigned int dccpap_buf_tail;
392 u64 dccpap_buf_ackno;
393 u64 dccpap_ack_seqno;
394 u64 dccpap_ack_ackno;
395 unsigned int dccpap_ack_ptr;
396 unsigned int dccpap_buf_vector_len;
397 unsigned int dccpap_ack_vector_len;
398 unsigned int dccpap_buf_len;
399 unsigned long dccpap_time;
400 u8 dccpap_buf_nonce;
401 u8 dccpap_ack_nonce;
402 u8 dccpap_buf[0];
403};
404
405extern struct dccp_ackpkts *dccp_ackpkts_alloc(unsigned int len, int priority);
406extern void dccp_ackpkts_free(struct dccp_ackpkts *ap);
407extern int dccp_ackpkts_add(struct dccp_ackpkts *ap, u64 ackno, u8 state);
408extern void dccp_ackpkts_check_rcv_ackno(struct dccp_ackpkts *ap,
409 struct sock *sk, u64 ackno);
410
411#ifdef DCCP_DEBUG
412extern void dccp_ackvector_print(const u64 ackno,
413 const unsigned char *vector, int len);
414extern void dccp_ackpkts_print(const struct dccp_ackpkts *ap);
415#else
416static inline void dccp_ackvector_print(const u64 ackno,
417 const unsigned char *vector,
418 int len) { }
419static inline void dccp_ackpkts_print(const struct dccp_ackpkts *ap) { }
420#endif
421
422#endif /* _DCCP_H */