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Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -07001#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
Arnaldo Carvalho de Melo27258ee2005-08-09 20:30:56 -0700125extern int dccp_write_xmit(struct sock *sk, struct sk_buff *skb,
126 const int len);
127
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700128extern void dccp_init_xmit_timers(struct sock *sk);
129static inline void dccp_clear_xmit_timers(struct sock *sk)
130{
131 inet_csk_clear_xmit_timers(sk);
132}
133
134extern unsigned int dccp_sync_mss(struct sock *sk, u32 pmtu);
135
136extern const char *dccp_packet_name(const int type);
137extern const char *dccp_state_name(const int state);
138
139static inline void dccp_set_state(struct sock *sk, const int state)
140{
141 const int oldstate = sk->sk_state;
142
143 dccp_pr_debug("%s(%p) %-10.10s -> %s\n",
144 dccp_role(sk), sk,
145 dccp_state_name(oldstate), dccp_state_name(state));
146 WARN_ON(state == oldstate);
147
148 switch (state) {
149 case DCCP_OPEN:
150 if (oldstate != DCCP_OPEN)
151 DCCP_INC_STATS(DCCP_MIB_CURRESTAB);
152 break;
153
154 case DCCP_CLOSED:
155 if (oldstate == DCCP_CLOSING || oldstate == DCCP_OPEN)
156 DCCP_INC_STATS(DCCP_MIB_ESTABRESETS);
157
158 sk->sk_prot->unhash(sk);
159 if (inet_csk(sk)->icsk_bind_hash != NULL &&
160 !(sk->sk_userlocks & SOCK_BINDPORT_LOCK))
161 inet_put_port(&dccp_hashinfo, sk);
162 /* fall through */
163 default:
164 if (oldstate == DCCP_OPEN)
165 DCCP_DEC_STATS(DCCP_MIB_CURRESTAB);
166 }
167
168 /* Change state AFTER socket is unhashed to avoid closed
169 * socket sitting in hash tables.
170 */
171 sk->sk_state = state;
172}
173
174static inline void dccp_done(struct sock *sk)
175{
176 dccp_set_state(sk, DCCP_CLOSED);
177 dccp_clear_xmit_timers(sk);
178
179 sk->sk_shutdown = SHUTDOWN_MASK;
180
181 if (!sock_flag(sk, SOCK_DEAD))
182 sk->sk_state_change(sk);
183 else
184 inet_csk_destroy_sock(sk);
185}
186
187static inline void dccp_openreq_init(struct request_sock *req,
188 struct dccp_sock *dp,
189 struct sk_buff *skb)
190{
191 /*
192 * FIXME: fill in the other req fields from the DCCP options
193 * received
194 */
195 inet_rsk(req)->rmt_port = dccp_hdr(skb)->dccph_sport;
196 inet_rsk(req)->acked = 0;
197 req->rcv_wnd = 0;
198}
199
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700200extern int dccp_v4_conn_request(struct sock *sk, struct sk_buff *skb);
201
202extern struct sock *dccp_create_openreq_child(struct sock *sk,
203 const struct request_sock *req,
204 const struct sk_buff *skb);
205
206extern int dccp_v4_do_rcv(struct sock *sk, struct sk_buff *skb);
207
208extern void dccp_v4_err(struct sk_buff *skb, u32);
209
210extern int dccp_v4_rcv(struct sk_buff *skb);
211
212extern struct sock *dccp_v4_request_recv_sock(struct sock *sk,
213 struct sk_buff *skb,
214 struct request_sock *req,
215 struct dst_entry *dst);
216extern struct sock *dccp_check_req(struct sock *sk, struct sk_buff *skb,
217 struct request_sock *req,
218 struct request_sock **prev);
219
220extern int dccp_child_process(struct sock *parent, struct sock *child,
221 struct sk_buff *skb);
222extern int dccp_rcv_state_process(struct sock *sk, struct sk_buff *skb,
223 struct dccp_hdr *dh, unsigned len);
224extern int dccp_rcv_established(struct sock *sk, struct sk_buff *skb,
225 const struct dccp_hdr *dh, const unsigned len);
226
227extern void dccp_close(struct sock *sk, long timeout);
228extern struct sk_buff *dccp_make_response(struct sock *sk,
229 struct dst_entry *dst,
230 struct request_sock *req);
231
232extern int dccp_connect(struct sock *sk);
233extern int dccp_disconnect(struct sock *sk, int flags);
234extern int dccp_getsockopt(struct sock *sk, int level, int optname,
235 char *optval, int *optlen);
236extern int dccp_ioctl(struct sock *sk, int cmd, unsigned long arg);
237extern int dccp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
238 size_t size);
239extern int dccp_recvmsg(struct kiocb *iocb, struct sock *sk,
240 struct msghdr *msg, size_t len, int nonblock,
241 int flags, int *addr_len);
242extern int dccp_setsockopt(struct sock *sk, int level, int optname,
243 char *optval, int optlen);
244extern void dccp_shutdown(struct sock *sk, int how);
245
Yoshifumi Nishida95b81ef2005-08-09 20:15:35 -0700246extern int dccp_v4_checksum(const struct sk_buff *skb,
247 const u32 saddr, const u32 daddr);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700248
249extern int dccp_v4_send_reset(struct sock *sk, enum dccp_reset_codes code);
250extern void dccp_send_close(struct sock *sk);
251
252struct dccp_skb_cb {
253 __u8 dccpd_type;
254 __u8 dccpd_reset_code;
255 __u8 dccpd_service;
256 __u8 dccpd_ccval;
257 __u64 dccpd_seq;
258 __u64 dccpd_ack_seq;
259 int dccpd_opt_len;
260};
261
262#define DCCP_SKB_CB(__skb) ((struct dccp_skb_cb *)&((__skb)->cb[0]))
263
264static inline int dccp_non_data_packet(const struct sk_buff *skb)
265{
266 const __u8 type = DCCP_SKB_CB(skb)->dccpd_type;
267
268 return type == DCCP_PKT_ACK ||
269 type == DCCP_PKT_CLOSE ||
270 type == DCCP_PKT_CLOSEREQ ||
271 type == DCCP_PKT_RESET ||
272 type == DCCP_PKT_SYNC ||
273 type == DCCP_PKT_SYNCACK;
274}
275
276static inline int dccp_packet_without_ack(const struct sk_buff *skb)
277{
278 const __u8 type = DCCP_SKB_CB(skb)->dccpd_type;
279
280 return type == DCCP_PKT_DATA || type == DCCP_PKT_REQUEST;
281}
282
283#define DCCP_MAX_SEQNO ((((u64)1) << 48) - 1)
284#define DCCP_PKT_WITHOUT_ACK_SEQ (DCCP_MAX_SEQNO << 2)
285
286static inline void dccp_set_seqno(u64 *seqno, u64 value)
287{
288 if (value > DCCP_MAX_SEQNO)
289 value -= DCCP_MAX_SEQNO + 1;
290 *seqno = value;
291}
292
293static inline u64 dccp_delta_seqno(u64 seqno1, u64 seqno2)
294{
295 return ((seqno2 << 16) - (seqno1 << 16)) >> 16;
296}
297
298static inline void dccp_inc_seqno(u64 *seqno)
299{
300 if (++*seqno > DCCP_MAX_SEQNO)
301 *seqno = 0;
302}
303
304static inline void dccp_hdr_set_seq(struct dccp_hdr *dh, const u64 gss)
305{
306 struct dccp_hdr_ext *dhx = (struct dccp_hdr_ext *)((void *)dh + sizeof(*dh));
307
308#if defined(__LITTLE_ENDIAN_BITFIELD)
309 dh->dccph_seq = htonl((gss >> 32)) >> 8;
310#elif defined(__BIG_ENDIAN_BITFIELD)
311 dh->dccph_seq = htonl((gss >> 32));
312#else
313#error "Adjust your <asm/byteorder.h> defines"
314#endif
315 dhx->dccph_seq_low = htonl(gss & 0xffffffff);
316}
317
318static inline void dccp_hdr_set_ack(struct dccp_hdr_ack_bits *dhack, const u64 gsr)
319{
320#if defined(__LITTLE_ENDIAN_BITFIELD)
321 dhack->dccph_ack_nr_high = htonl((gsr >> 32)) >> 8;
322#elif defined(__BIG_ENDIAN_BITFIELD)
323 dhack->dccph_ack_nr_high = htonl((gsr >> 32));
324#else
325#error "Adjust your <asm/byteorder.h> defines"
326#endif
327 dhack->dccph_ack_nr_low = htonl(gsr & 0xffffffff);
328}
329
330static inline void dccp_update_gsr(struct sock *sk, u64 seq)
331{
332 struct dccp_sock *dp = dccp_sk(sk);
333 u64 tmp_gsr;
334
335 dccp_set_seqno(&tmp_gsr, dp->dccps_gsr + 1 - (dp->dccps_options.dccpo_sequence_window / 4));
336 dp->dccps_gsr = seq;
337 dccp_set_seqno(&dp->dccps_swl, max48(tmp_gsr, dp->dccps_isr));
338 dccp_set_seqno(&dp->dccps_swh,
339 dp->dccps_gsr + (3 * dp->dccps_options.dccpo_sequence_window) / 4);
340}
341
342static inline void dccp_update_gss(struct sock *sk, u64 seq)
343{
344 struct dccp_sock *dp = dccp_sk(sk);
345 u64 tmp_gss;
346
347 dccp_set_seqno(&tmp_gss, dp->dccps_gss - dp->dccps_options.dccpo_sequence_window + 1);
348 dp->dccps_awl = max48(tmp_gss, dp->dccps_iss);
349 dp->dccps_awh = dp->dccps_gss = seq;
350}
351
352extern void dccp_insert_options(struct sock *sk, struct sk_buff *skb);
353extern void dccp_insert_option_elapsed_time(struct sock *sk,
354 struct sk_buff *skb,
355 u32 elapsed_time);
356extern void dccp_insert_option(struct sock *sk, struct sk_buff *skb,
357 unsigned char option,
358 const void *value, unsigned char len);
359
360extern struct socket *dccp_ctl_socket;
361
362#define DCCP_ACKPKTS_STATE_RECEIVED 0
363#define DCCP_ACKPKTS_STATE_ECN_MARKED (1 << 6)
364#define DCCP_ACKPKTS_STATE_NOT_RECEIVED (3 << 6)
365
366#define DCCP_ACKPKTS_STATE_MASK 0xC0 /* 11000000 */
367#define DCCP_ACKPKTS_LEN_MASK 0x3F /* 00111111 */
368
369/** struct dccp_ackpkts - acknowledgeable packets
370 *
371 * This data structure is the one defined in the DCCP draft
372 * Appendix A.
373 *
374 * @dccpap_buf_head - circular buffer head
375 * @dccpap_buf_tail - circular buffer tail
376 * @dccpap_buf_ackno - ack # of the most recent packet acknoldgeable in the buffer (i.e. %dccpap_buf_head)
377 * @dccpap_buf_nonce - the one-bit sum of the ECN Nonces on all packets acked by the buffer with State 0
378 *
379 * Additionally, the HC-Receiver must keep some information about the
380 * Ack Vectors it has recently sent. For each packet sent carrying an
381 * Ack Vector, it remembers four variables:
382 *
383 * @dccpap_ack_seqno - the Sequence Number used for the packet (HC-Receiver seqno)
384 * @dccpap_ack_ptr - the value of buf_head at the time of acknowledgement.
385 * @dccpap_ack_ackno - the Acknowledgement Number used for the packet (HC-Sender seqno)
386 * @dccpap_ack_nonce - the one-bit sum of the ECN Nonces for all State 0.
387 *
388 * @dccpap_buf_len - circular buffer length
389 * @dccpap_buf - circular buffer of acknowledgeable packets
390 */
391struct dccp_ackpkts {
392 unsigned int dccpap_buf_head;
393 unsigned int dccpap_buf_tail;
394 u64 dccpap_buf_ackno;
395 u64 dccpap_ack_seqno;
396 u64 dccpap_ack_ackno;
397 unsigned int dccpap_ack_ptr;
398 unsigned int dccpap_buf_vector_len;
399 unsigned int dccpap_ack_vector_len;
400 unsigned int dccpap_buf_len;
401 unsigned long dccpap_time;
402 u8 dccpap_buf_nonce;
403 u8 dccpap_ack_nonce;
404 u8 dccpap_buf[0];
405};
406
407extern struct dccp_ackpkts *dccp_ackpkts_alloc(unsigned int len, int priority);
408extern void dccp_ackpkts_free(struct dccp_ackpkts *ap);
409extern int dccp_ackpkts_add(struct dccp_ackpkts *ap, u64 ackno, u8 state);
410extern void dccp_ackpkts_check_rcv_ackno(struct dccp_ackpkts *ap,
411 struct sock *sk, u64 ackno);
412
413#ifdef DCCP_DEBUG
414extern void dccp_ackvector_print(const u64 ackno,
415 const unsigned char *vector, int len);
416extern void dccp_ackpkts_print(const struct dccp_ackpkts *ap);
417#else
418static inline void dccp_ackvector_print(const u64 ackno,
419 const unsigned char *vector,
420 int len) { }
421static inline void dccp_ackpkts_print(const struct dccp_ackpkts *ap) { }
422#endif
423
424#endif /* _DCCP_H */