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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
Arnaldo Carvalho de Melo725ba8e2005-08-13 20:35:39 -030014#include <linux/config.h>
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -070015#include <linux/dccp.h>
16#include <net/snmp.h>
17#include <net/sock.h>
18#include <net/tcp.h>
19
Arnaldo Carvalho de Melo725ba8e2005-08-13 20:35:39 -030020#ifdef CONFIG_IP_DCCP_DEBUG
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -070021extern int dccp_debug;
22
23#define dccp_pr_debug(format, a...) \
24 do { if (dccp_debug) \
25 printk(KERN_DEBUG "%s: " format, __FUNCTION__ , ##a); \
26 } while (0)
Arnaldo Carvalho de Melo7690af32005-08-13 20:34:54 -030027#define dccp_pr_debug_cat(format, a...) do { if (dccp_debug) \
28 printk(format, ##a); } while (0)
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -070029#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 ? */
Patrick McHardya10cedd2005-08-14 21:05:53 -030063static inline int before48(const u64 seq1, const u64 seq2)
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -070064{
Patrick McHardya10cedd2005-08-14 21:05:53 -030065 return (s64)((seq1 << 16) - (seq2 << 16)) < 0;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -070066}
67
68/* is seq1 > seq2 ? */
Patrick McHardya10cedd2005-08-14 21:05:53 -030069static inline int after48(const u64 seq1, const u64 seq2)
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -070070{
Patrick McHardya10cedd2005-08-14 21:05:53 -030071 return (s64)((seq2 << 16) - (seq1 << 16)) < 0;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -070072}
73
74/* is seq2 <= seq1 <= seq3 ? */
Patrick McHardya10cedd2005-08-14 21:05:53 -030075static inline int between48(const u64 seq1, const u64 seq2, const u64 seq3)
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -070076{
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);
Arnaldo Carvalho de Melo7690af32005-08-13 20:34:54 -0300110#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) \
115 SNMP_ADD_STATS_BH(dccp_statistics, field, val)
116#define DCCP_ADD_STATS_USER(field, val) \
117 SNMP_ADD_STATS_USER(dccp_statistics, field, val)
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700118
119extern int dccp_transmit_skb(struct sock *sk, struct sk_buff *skb);
120extern int dccp_retransmit_skb(struct sock *sk, struct sk_buff *skb);
121
122extern int dccp_send_response(struct sock *sk);
123extern void dccp_send_ack(struct sock *sk);
124extern void dccp_send_delayed_ack(struct sock *sk);
Arnaldo Carvalho de Meloe92ae932005-08-17 03:10:59 -0300125extern void dccp_send_sync(struct sock *sk, const u64 seq,
126 const enum dccp_pkt_type pkt_type);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700127
Arnaldo Carvalho de Melo27258ee2005-08-09 20:30:56 -0700128extern int dccp_write_xmit(struct sock *sk, struct sk_buff *skb,
129 const int len);
130
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700131extern void dccp_init_xmit_timers(struct sock *sk);
132static inline void dccp_clear_xmit_timers(struct sock *sk)
133{
134 inet_csk_clear_xmit_timers(sk);
135}
136
137extern unsigned int dccp_sync_mss(struct sock *sk, u32 pmtu);
138
139extern const char *dccp_packet_name(const int type);
140extern const char *dccp_state_name(const int state);
141
142static inline void dccp_set_state(struct sock *sk, const int state)
143{
144 const int oldstate = sk->sk_state;
145
146 dccp_pr_debug("%s(%p) %-10.10s -> %s\n",
147 dccp_role(sk), sk,
148 dccp_state_name(oldstate), dccp_state_name(state));
149 WARN_ON(state == oldstate);
150
151 switch (state) {
152 case DCCP_OPEN:
153 if (oldstate != DCCP_OPEN)
154 DCCP_INC_STATS(DCCP_MIB_CURRESTAB);
155 break;
156
157 case DCCP_CLOSED:
158 if (oldstate == DCCP_CLOSING || oldstate == DCCP_OPEN)
159 DCCP_INC_STATS(DCCP_MIB_ESTABRESETS);
160
161 sk->sk_prot->unhash(sk);
162 if (inet_csk(sk)->icsk_bind_hash != NULL &&
163 !(sk->sk_userlocks & SOCK_BINDPORT_LOCK))
164 inet_put_port(&dccp_hashinfo, sk);
165 /* fall through */
166 default:
167 if (oldstate == DCCP_OPEN)
168 DCCP_DEC_STATS(DCCP_MIB_CURRESTAB);
169 }
170
171 /* Change state AFTER socket is unhashed to avoid closed
172 * socket sitting in hash tables.
173 */
174 sk->sk_state = state;
175}
176
177static inline void dccp_done(struct sock *sk)
178{
179 dccp_set_state(sk, DCCP_CLOSED);
180 dccp_clear_xmit_timers(sk);
181
182 sk->sk_shutdown = SHUTDOWN_MASK;
183
184 if (!sock_flag(sk, SOCK_DEAD))
185 sk->sk_state_change(sk);
186 else
187 inet_csk_destroy_sock(sk);
188}
189
190static inline void dccp_openreq_init(struct request_sock *req,
191 struct dccp_sock *dp,
192 struct sk_buff *skb)
193{
194 /*
195 * FIXME: fill in the other req fields from the DCCP options
196 * received
197 */
198 inet_rsk(req)->rmt_port = dccp_hdr(skb)->dccph_sport;
199 inet_rsk(req)->acked = 0;
200 req->rcv_wnd = 0;
201}
202
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700203extern int dccp_v4_conn_request(struct sock *sk, struct sk_buff *skb);
204
205extern struct sock *dccp_create_openreq_child(struct sock *sk,
206 const struct request_sock *req,
207 const struct sk_buff *skb);
208
209extern int dccp_v4_do_rcv(struct sock *sk, struct sk_buff *skb);
210
211extern void dccp_v4_err(struct sk_buff *skb, u32);
212
213extern int dccp_v4_rcv(struct sk_buff *skb);
214
215extern struct sock *dccp_v4_request_recv_sock(struct sock *sk,
216 struct sk_buff *skb,
217 struct request_sock *req,
218 struct dst_entry *dst);
219extern struct sock *dccp_check_req(struct sock *sk, struct sk_buff *skb,
220 struct request_sock *req,
221 struct request_sock **prev);
222
223extern int dccp_child_process(struct sock *parent, struct sock *child,
224 struct sk_buff *skb);
225extern int dccp_rcv_state_process(struct sock *sk, struct sk_buff *skb,
226 struct dccp_hdr *dh, unsigned len);
227extern int dccp_rcv_established(struct sock *sk, struct sk_buff *skb,
228 const struct dccp_hdr *dh, const unsigned len);
229
230extern void dccp_close(struct sock *sk, long timeout);
231extern struct sk_buff *dccp_make_response(struct sock *sk,
232 struct dst_entry *dst,
233 struct request_sock *req);
Arnaldo Carvalho de Meloa1d3a352005-08-13 22:42:25 -0300234extern struct sk_buff *dccp_make_reset(struct sock *sk,
235 struct dst_entry *dst,
236 enum dccp_reset_codes code);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700237
238extern int dccp_connect(struct sock *sk);
239extern int dccp_disconnect(struct sock *sk, int flags);
240extern int dccp_getsockopt(struct sock *sk, int level, int optname,
Arnaldo Carvalho de Meloa1d3a352005-08-13 22:42:25 -0300241 char __user *optval, int __user *optlen);
242extern int dccp_setsockopt(struct sock *sk, int level, int optname,
243 char __user *optval, int optlen);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700244extern int dccp_ioctl(struct sock *sk, int cmd, unsigned long arg);
Arnaldo Carvalho de Melo7690af32005-08-13 20:34:54 -0300245extern int dccp_sendmsg(struct kiocb *iocb, struct sock *sk,
246 struct msghdr *msg, size_t size);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700247extern int dccp_recvmsg(struct kiocb *iocb, struct sock *sk,
248 struct msghdr *msg, size_t len, int nonblock,
249 int flags, int *addr_len);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700250extern void dccp_shutdown(struct sock *sk, int how);
251
Yoshifumi Nishida95b81ef2005-08-09 20:15:35 -0700252extern int dccp_v4_checksum(const struct sk_buff *skb,
253 const u32 saddr, const u32 daddr);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700254
Arnaldo Carvalho de Melo7690af32005-08-13 20:34:54 -0300255extern int dccp_v4_send_reset(struct sock *sk,
256 enum dccp_reset_codes code);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700257extern void dccp_send_close(struct sock *sk);
258
259struct dccp_skb_cb {
260 __u8 dccpd_type;
261 __u8 dccpd_reset_code;
262 __u8 dccpd_service;
263 __u8 dccpd_ccval;
264 __u64 dccpd_seq;
265 __u64 dccpd_ack_seq;
266 int dccpd_opt_len;
267};
268
269#define DCCP_SKB_CB(__skb) ((struct dccp_skb_cb *)&((__skb)->cb[0]))
270
271static inline int dccp_non_data_packet(const struct sk_buff *skb)
272{
273 const __u8 type = DCCP_SKB_CB(skb)->dccpd_type;
274
275 return type == DCCP_PKT_ACK ||
276 type == DCCP_PKT_CLOSE ||
277 type == DCCP_PKT_CLOSEREQ ||
278 type == DCCP_PKT_RESET ||
279 type == DCCP_PKT_SYNC ||
280 type == DCCP_PKT_SYNCACK;
281}
282
283static inline int dccp_packet_without_ack(const struct sk_buff *skb)
284{
285 const __u8 type = DCCP_SKB_CB(skb)->dccpd_type;
286
287 return type == DCCP_PKT_DATA || type == DCCP_PKT_REQUEST;
288}
289
290#define DCCP_MAX_SEQNO ((((u64)1) << 48) - 1)
291#define DCCP_PKT_WITHOUT_ACK_SEQ (DCCP_MAX_SEQNO << 2)
292
293static inline void dccp_set_seqno(u64 *seqno, u64 value)
294{
295 if (value > DCCP_MAX_SEQNO)
296 value -= DCCP_MAX_SEQNO + 1;
297 *seqno = value;
298}
299
300static inline u64 dccp_delta_seqno(u64 seqno1, u64 seqno2)
301{
302 return ((seqno2 << 16) - (seqno1 << 16)) >> 16;
303}
304
305static inline void dccp_inc_seqno(u64 *seqno)
306{
307 if (++*seqno > DCCP_MAX_SEQNO)
308 *seqno = 0;
309}
310
311static inline void dccp_hdr_set_seq(struct dccp_hdr *dh, const u64 gss)
312{
Arnaldo Carvalho de Melo7690af32005-08-13 20:34:54 -0300313 struct dccp_hdr_ext *dhx = (struct dccp_hdr_ext *)((void *)dh +
314 sizeof(*dh));
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700315
316#if defined(__LITTLE_ENDIAN_BITFIELD)
317 dh->dccph_seq = htonl((gss >> 32)) >> 8;
318#elif defined(__BIG_ENDIAN_BITFIELD)
319 dh->dccph_seq = htonl((gss >> 32));
320#else
321#error "Adjust your <asm/byteorder.h> defines"
322#endif
323 dhx->dccph_seq_low = htonl(gss & 0xffffffff);
324}
325
Arnaldo Carvalho de Melo7690af32005-08-13 20:34:54 -0300326static inline void dccp_hdr_set_ack(struct dccp_hdr_ack_bits *dhack,
327 const u64 gsr)
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700328{
329#if defined(__LITTLE_ENDIAN_BITFIELD)
330 dhack->dccph_ack_nr_high = htonl((gsr >> 32)) >> 8;
331#elif defined(__BIG_ENDIAN_BITFIELD)
332 dhack->dccph_ack_nr_high = htonl((gsr >> 32));
333#else
334#error "Adjust your <asm/byteorder.h> defines"
335#endif
336 dhack->dccph_ack_nr_low = htonl(gsr & 0xffffffff);
337}
338
339static inline void dccp_update_gsr(struct sock *sk, u64 seq)
340{
341 struct dccp_sock *dp = dccp_sk(sk);
342 u64 tmp_gsr;
343
Arnaldo Carvalho de Melo7690af32005-08-13 20:34:54 -0300344 dccp_set_seqno(&tmp_gsr,
345 (dp->dccps_gsr + 1 -
346 (dp->dccps_options.dccpo_sequence_window / 4)));
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700347 dp->dccps_gsr = seq;
348 dccp_set_seqno(&dp->dccps_swl, max48(tmp_gsr, dp->dccps_isr));
349 dccp_set_seqno(&dp->dccps_swh,
Arnaldo Carvalho de Melo7690af32005-08-13 20:34:54 -0300350 (dp->dccps_gsr +
351 (3 * dp->dccps_options.dccpo_sequence_window) / 4));
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700352}
353
354static inline void dccp_update_gss(struct sock *sk, u64 seq)
355{
356 struct dccp_sock *dp = dccp_sk(sk);
357 u64 tmp_gss;
358
Arnaldo Carvalho de Melo7690af32005-08-13 20:34:54 -0300359 dccp_set_seqno(&tmp_gss,
360 (dp->dccps_gss -
361 dp->dccps_options.dccpo_sequence_window + 1));
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700362 dp->dccps_awl = max48(tmp_gss, dp->dccps_iss);
363 dp->dccps_awh = dp->dccps_gss = seq;
364}
365
366extern void dccp_insert_options(struct sock *sk, struct sk_buff *skb);
367extern void dccp_insert_option_elapsed_time(struct sock *sk,
368 struct sk_buff *skb,
369 u32 elapsed_time);
370extern void dccp_insert_option(struct sock *sk, struct sk_buff *skb,
371 unsigned char option,
372 const void *value, unsigned char len);
373
374extern struct socket *dccp_ctl_socket;
375
376#define DCCP_ACKPKTS_STATE_RECEIVED 0
377#define DCCP_ACKPKTS_STATE_ECN_MARKED (1 << 6)
378#define DCCP_ACKPKTS_STATE_NOT_RECEIVED (3 << 6)
379
380#define DCCP_ACKPKTS_STATE_MASK 0xC0 /* 11000000 */
381#define DCCP_ACKPKTS_LEN_MASK 0x3F /* 00111111 */
382
383/** struct dccp_ackpkts - acknowledgeable packets
384 *
385 * This data structure is the one defined in the DCCP draft
386 * Appendix A.
387 *
388 * @dccpap_buf_head - circular buffer head
389 * @dccpap_buf_tail - circular buffer tail
Arnaldo Carvalho de Melo7690af32005-08-13 20:34:54 -0300390 * @dccpap_buf_ackno - ack # of the most recent packet acknowledgeable in the
391 * buffer (i.e. %dccpap_buf_head)
392 * @dccpap_buf_nonce - the one-bit sum of the ECN Nonces on all packets acked
393 * by the buffer with State 0
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700394 *
395 * Additionally, the HC-Receiver must keep some information about the
396 * Ack Vectors it has recently sent. For each packet sent carrying an
397 * Ack Vector, it remembers four variables:
398 *
Arnaldo Carvalho de Melo7690af32005-08-13 20:34:54 -0300399 * @dccpap_ack_seqno - the Sequence Number used for the packet
400 * (HC-Receiver seqno)
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700401 * @dccpap_ack_ptr - the value of buf_head at the time of acknowledgement.
Arnaldo Carvalho de Melo7690af32005-08-13 20:34:54 -0300402 * @dccpap_ack_ackno - the Acknowledgement Number used for the packet
403 * (HC-Sender seqno)
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700404 * @dccpap_ack_nonce - the one-bit sum of the ECN Nonces for all State 0.
405 *
406 * @dccpap_buf_len - circular buffer length
407 * @dccpap_buf - circular buffer of acknowledgeable packets
408 */
409struct dccp_ackpkts {
410 unsigned int dccpap_buf_head;
411 unsigned int dccpap_buf_tail;
412 u64 dccpap_buf_ackno;
413 u64 dccpap_ack_seqno;
414 u64 dccpap_ack_ackno;
415 unsigned int dccpap_ack_ptr;
416 unsigned int dccpap_buf_vector_len;
417 unsigned int dccpap_ack_vector_len;
418 unsigned int dccpap_buf_len;
419 unsigned long dccpap_time;
420 u8 dccpap_buf_nonce;
421 u8 dccpap_ack_nonce;
422 u8 dccpap_buf[0];
423};
424
Arnaldo Carvalho de Meloa1d3a352005-08-13 22:42:25 -0300425extern struct dccp_ackpkts *
426 dccp_ackpkts_alloc(unsigned int len,
427 const unsigned int __nocast priority);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700428extern void dccp_ackpkts_free(struct dccp_ackpkts *ap);
429extern int dccp_ackpkts_add(struct dccp_ackpkts *ap, u64 ackno, u8 state);
430extern void dccp_ackpkts_check_rcv_ackno(struct dccp_ackpkts *ap,
431 struct sock *sk, u64 ackno);
432
Arnaldo Carvalho de Melo725ba8e2005-08-13 20:35:39 -0300433#ifdef CONFIG_IP_DCCP_DEBUG
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700434extern void dccp_ackvector_print(const u64 ackno,
435 const unsigned char *vector, int len);
436extern void dccp_ackpkts_print(const struct dccp_ackpkts *ap);
437#else
438static inline void dccp_ackvector_print(const u64 ackno,
439 const unsigned char *vector,
440 int len) { }
441static inline void dccp_ackpkts_print(const struct dccp_ackpkts *ap) { }
442#endif
443
444#endif /* _DCCP_H */