6 * An implementation of the DCCP protocol
7 * Arnaldo Carvalho de Melo <acme@conectiva.com.br>
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.
14 #include <linux/dccp.h>
22 extern int dccp_debug
;
24 #define dccp_pr_debug(format, a...) \
25 do { if (dccp_debug) \
26 printk(KERN_DEBUG "%s: " format, __FUNCTION__ , ##a); \
28 #define dccp_pr_debug_cat(format, a...) do { if (dccp_debug) printk(format, ##a); } while (0)
30 #define dccp_pr_debug(format, a...)
31 #define dccp_pr_debug_cat(format, a...)
34 extern struct inet_hashinfo dccp_hashinfo
;
36 extern atomic_t dccp_orphan_count
;
37 extern int dccp_tw_count
;
38 extern void dccp_tw_deschedule(struct inet_timewait_sock
*tw
);
40 extern void dccp_time_wait(struct sock
*sk
, int state
, int timeo
);
42 /* FIXME: Right size this */
43 #define DCCP_MAX_OPT_LEN 128
45 #define DCCP_MAX_PACKET_HDR 32
47 #define MAX_DCCP_HEADER (DCCP_MAX_PACKET_HDR + DCCP_MAX_OPT_LEN + MAX_HEADER)
49 #define DCCP_TIMEWAIT_LEN (60 * HZ) /* how long to wait to destroy TIME-WAIT
50 * state, about 60 seconds */
52 /* draft-ietf-dccp-spec-11.txt initial RTO value */
53 #define DCCP_TIMEOUT_INIT ((unsigned)(3 * HZ))
55 /* Maximal interval between probes for local resources. */
56 #define DCCP_RESOURCE_PROBE_INTERVAL ((unsigned)(HZ / 2U))
58 #define DCCP_RTO_MAX ((unsigned)(120 * HZ)) /* FIXME: using TCP value */
60 extern struct proto dccp_v4_prot
;
62 /* is seq1 < seq2 ? */
63 static inline const int before48(const u64 seq1
, const u64 seq2
)
65 return (const s64
)((seq1
<< 16) - (seq2
<< 16)) < 0;
68 /* is seq1 > seq2 ? */
69 static inline const int after48(const u64 seq1
, const u64 seq2
)
71 return (const s64
)((seq2
<< 16) - (seq1
<< 16)) < 0;
74 /* is seq2 <= seq1 <= seq3 ? */
75 static inline const int between48(const u64 seq1
, const u64 seq2
, const u64 seq3
)
77 return (seq3
<< 16) - (seq2
<< 16) >= (seq1
<< 16) - (seq2
<< 16);
80 static inline u64
max48(const u64 seq1
, const u64 seq2
)
82 return after48(seq1
, seq2
) ? seq1
: seq2
;
87 DCCP_MIB_ACTIVEOPENS
, /* ActiveOpens */
88 DCCP_MIB_ESTABRESETS
, /* EstabResets */
89 DCCP_MIB_CURRESTAB
, /* CurrEstab */
90 DCCP_MIB_OUTSEGS
, /* OutSegs */
92 DCCP_MIB_ABORTONTIMEOUT
,
95 DCCP_MIB_PASSIVEOPENS
,
96 DCCP_MIB_ATTEMPTFAILS
,
97 DCCP_MIB_OUTDATAGRAMS
,
99 DCCP_MIB_OPTMANDATORYERROR
,
104 #define DCCP_MIB_MAX __DCCP_MIB_MAX
106 unsigned long mibs
[DCCP_MIB_MAX
];
107 } __SNMP_MIB_ALIGN__
;
109 DECLARE_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)
117 extern int dccp_transmit_skb(struct sock
*sk
, struct sk_buff
*skb
);
118 extern int dccp_retransmit_skb(struct sock
*sk
, struct sk_buff
*skb
);
120 extern int dccp_send_response(struct sock
*sk
);
121 extern void dccp_send_ack(struct sock
*sk
);
122 extern void dccp_send_delayed_ack(struct sock
*sk
);
123 extern void dccp_send_sync(struct sock
*sk
, u64 seq
);
125 extern void dccp_init_xmit_timers(struct sock
*sk
);
126 static inline void dccp_clear_xmit_timers(struct sock
*sk
)
128 inet_csk_clear_xmit_timers(sk
);
131 extern unsigned int dccp_sync_mss(struct sock
*sk
, u32 pmtu
);
133 extern const char *dccp_packet_name(const int type
);
134 extern const char *dccp_state_name(const int state
);
136 static inline void dccp_set_state(struct sock
*sk
, const int state
)
138 const int oldstate
= sk
->sk_state
;
140 dccp_pr_debug("%s(%p) %-10.10s -> %s\n",
142 dccp_state_name(oldstate
), dccp_state_name(state
));
143 WARN_ON(state
== oldstate
);
147 if (oldstate
!= DCCP_OPEN
)
148 DCCP_INC_STATS(DCCP_MIB_CURRESTAB
);
152 if (oldstate
== DCCP_CLOSING
|| oldstate
== DCCP_OPEN
)
153 DCCP_INC_STATS(DCCP_MIB_ESTABRESETS
);
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
);
161 if (oldstate
== DCCP_OPEN
)
162 DCCP_DEC_STATS(DCCP_MIB_CURRESTAB
);
165 /* Change state AFTER socket is unhashed to avoid closed
166 * socket sitting in hash tables.
168 sk
->sk_state
= state
;
171 static inline void dccp_done(struct sock
*sk
)
173 dccp_set_state(sk
, DCCP_CLOSED
);
174 dccp_clear_xmit_timers(sk
);
176 sk
->sk_shutdown
= SHUTDOWN_MASK
;
178 if (!sock_flag(sk
, SOCK_DEAD
))
179 sk
->sk_state_change(sk
);
181 inet_csk_destroy_sock(sk
);
184 static inline void dccp_openreq_init(struct request_sock
*req
,
185 struct dccp_sock
*dp
,
189 * FIXME: fill in the other req fields from the DCCP options
192 inet_rsk(req
)->rmt_port
= dccp_hdr(skb
)->dccph_sport
;
193 inet_rsk(req
)->acked
= 0;
197 extern void dccp_v4_send_check(struct sock
*sk
, struct dccp_hdr
*dh
, int len
,
198 struct sk_buff
*skb
);
199 extern int dccp_v4_conn_request(struct sock
*sk
, struct sk_buff
*skb
);
201 extern struct sock
*dccp_create_openreq_child(struct sock
*sk
,
202 const struct request_sock
*req
,
203 const struct sk_buff
*skb
);
205 extern int dccp_v4_do_rcv(struct sock
*sk
, struct sk_buff
*skb
);
207 extern void dccp_v4_err(struct sk_buff
*skb
, u32
);
209 extern int dccp_v4_rcv(struct sk_buff
*skb
);
211 extern struct sock
*dccp_v4_request_recv_sock(struct sock
*sk
,
213 struct request_sock
*req
,
214 struct dst_entry
*dst
);
215 extern struct sock
*dccp_check_req(struct sock
*sk
, struct sk_buff
*skb
,
216 struct request_sock
*req
,
217 struct request_sock
**prev
);
219 extern int dccp_child_process(struct sock
*parent
, struct sock
*child
,
220 struct sk_buff
*skb
);
221 extern int dccp_rcv_state_process(struct sock
*sk
, struct sk_buff
*skb
,
222 struct dccp_hdr
*dh
, unsigned len
);
223 extern int dccp_rcv_established(struct sock
*sk
, struct sk_buff
*skb
,
224 const struct dccp_hdr
*dh
, const unsigned len
);
226 extern void dccp_close(struct sock
*sk
, long timeout
);
227 extern struct sk_buff
*dccp_make_response(struct sock
*sk
,
228 struct dst_entry
*dst
,
229 struct request_sock
*req
);
231 extern int dccp_connect(struct sock
*sk
);
232 extern int dccp_disconnect(struct sock
*sk
, int flags
);
233 extern int dccp_getsockopt(struct sock
*sk
, int level
, int optname
,
234 char *optval
, int *optlen
);
235 extern int dccp_ioctl(struct sock
*sk
, int cmd
, unsigned long arg
);
236 extern int dccp_sendmsg(struct kiocb
*iocb
, struct sock
*sk
, struct msghdr
*msg
,
238 extern int dccp_recvmsg(struct kiocb
*iocb
, struct sock
*sk
,
239 struct msghdr
*msg
, size_t len
, int nonblock
,
240 int flags
, int *addr_len
);
241 extern int dccp_setsockopt(struct sock
*sk
, int level
, int optname
,
242 char *optval
, int optlen
);
243 extern void dccp_shutdown(struct sock
*sk
, int how
);
245 extern int dccp_v4_checksum(struct sk_buff
*skb
);
247 extern int dccp_v4_send_reset(struct sock
*sk
, enum dccp_reset_codes code
);
248 extern void dccp_send_close(struct sock
*sk
);
252 __u8 dccpd_reset_code
;
260 #define DCCP_SKB_CB(__skb) ((struct dccp_skb_cb *)&((__skb)->cb[0]))
262 static inline int dccp_non_data_packet(const struct sk_buff
*skb
)
264 const __u8 type
= DCCP_SKB_CB(skb
)->dccpd_type
;
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
;
274 static inline int dccp_packet_without_ack(const struct sk_buff
*skb
)
276 const __u8 type
= DCCP_SKB_CB(skb
)->dccpd_type
;
278 return type
== DCCP_PKT_DATA
|| type
== DCCP_PKT_REQUEST
;
281 #define DCCP_MAX_SEQNO ((((u64)1) << 48) - 1)
282 #define DCCP_PKT_WITHOUT_ACK_SEQ (DCCP_MAX_SEQNO << 2)
284 static inline void dccp_set_seqno(u64
*seqno
, u64 value
)
286 if (value
> DCCP_MAX_SEQNO
)
287 value
-= DCCP_MAX_SEQNO
+ 1;
291 static inline u64
dccp_delta_seqno(u64 seqno1
, u64 seqno2
)
293 return ((seqno2
<< 16) - (seqno1
<< 16)) >> 16;
296 static inline void dccp_inc_seqno(u64
*seqno
)
298 if (++*seqno
> DCCP_MAX_SEQNO
)
302 static inline void dccp_hdr_set_seq(struct dccp_hdr
*dh
, const u64 gss
)
304 struct dccp_hdr_ext
*dhx
= (struct dccp_hdr_ext
*)((void *)dh
+ sizeof(*dh
));
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));
311 #error "Adjust your <asm/byteorder.h> defines"
313 dhx
->dccph_seq_low
= htonl(gss
& 0xffffffff);
316 static inline void dccp_hdr_set_ack(struct dccp_hdr_ack_bits
*dhack
, const u64 gsr
)
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));
323 #error "Adjust your <asm/byteorder.h> defines"
325 dhack
->dccph_ack_nr_low
= htonl(gsr
& 0xffffffff);
328 static inline void dccp_update_gsr(struct sock
*sk
, u64 seq
)
330 struct dccp_sock
*dp
= dccp_sk(sk
);
333 dccp_set_seqno(&tmp_gsr
, dp
->dccps_gsr
+ 1 - (dp
->dccps_options
.dccpo_sequence_window
/ 4));
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);
340 static inline void dccp_update_gss(struct sock
*sk
, u64 seq
)
342 struct dccp_sock
*dp
= dccp_sk(sk
);
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
;
350 extern void dccp_insert_options(struct sock
*sk
, struct sk_buff
*skb
);
351 extern void dccp_insert_option_elapsed_time(struct sock
*sk
,
354 extern void dccp_insert_option(struct sock
*sk
, struct sk_buff
*skb
,
355 unsigned char option
,
356 const void *value
, unsigned char len
);
358 extern struct socket
*dccp_ctl_socket
;
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)
364 #define DCCP_ACKPKTS_STATE_MASK 0xC0 /* 11000000 */
365 #define DCCP_ACKPKTS_LEN_MASK 0x3F /* 00111111 */
367 /** struct dccp_ackpkts - acknowledgeable packets
369 * This data structure is the one defined in the DCCP draft
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
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:
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.
386 * @dccpap_buf_len - circular buffer length
387 * @dccpap_buf - circular buffer of acknowledgeable packets
389 struct 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
;
405 extern struct dccp_ackpkts
*dccp_ackpkts_alloc(unsigned int len
, int priority
);
406 extern void dccp_ackpkts_free(struct dccp_ackpkts
*ap
);
407 extern int dccp_ackpkts_add(struct dccp_ackpkts
*ap
, u64 ackno
, u8 state
);
408 extern void dccp_ackpkts_check_rcv_ackno(struct dccp_ackpkts
*ap
,
409 struct sock
*sk
, u64 ackno
);
412 extern void dccp_ackvector_print(const u64 ackno
,
413 const unsigned char *vector
, int len
);
414 extern void dccp_ackpkts_print(const struct dccp_ackpkts
*ap
);
416 static inline void dccp_ackvector_print(const u64 ackno
,
417 const unsigned char *vector
,
419 static inline void dccp_ackpkts_print(const struct dccp_ackpkts
*ap
) { }