Commit | Line | Data |
---|---|---|
7c657876 ACM |
1 | /* |
2 | * net/dccp/output.c | |
8109b02b | 3 | * |
7c657876 ACM |
4 | * An implementation of the DCCP protocol |
5 | * Arnaldo Carvalho de Melo <acme@conectiva.com.br> | |
6 | * | |
7 | * This program is free software; you can redistribute it and/or | |
8 | * modify it under the terms of the GNU General Public License | |
9 | * as published by the Free Software Foundation; either version | |
10 | * 2 of the License, or (at your option) any later version. | |
11 | */ | |
12 | ||
7c657876 | 13 | #include <linux/dccp.h> |
48918a4d | 14 | #include <linux/kernel.h> |
7c657876 ACM |
15 | #include <linux/skbuff.h> |
16 | ||
14c85021 | 17 | #include <net/inet_sock.h> |
7c657876 ACM |
18 | #include <net/sock.h> |
19 | ||
ae31c339 | 20 | #include "ackvec.h" |
7c657876 ACM |
21 | #include "ccid.h" |
22 | #include "dccp.h" | |
23 | ||
24 | static inline void dccp_event_ack_sent(struct sock *sk) | |
25 | { | |
26 | inet_csk_clear_xmit_timer(sk, ICSK_TIME_DACK); | |
27 | } | |
28 | ||
c25a18ba | 29 | static void dccp_skb_entail(struct sock *sk, struct sk_buff *skb) |
48918a4d HX |
30 | { |
31 | skb_set_owner_w(skb, sk); | |
32 | WARN_ON(sk->sk_send_head); | |
33 | sk->sk_send_head = skb; | |
34 | } | |
35 | ||
7c657876 ACM |
36 | /* |
37 | * All SKB's seen here are completely headerless. It is our | |
38 | * job to build the DCCP header, and pass the packet down to | |
39 | * IP so it can do the same plus pass the packet off to the | |
40 | * device. | |
41 | */ | |
48918a4d | 42 | static int dccp_transmit_skb(struct sock *sk, struct sk_buff *skb) |
7c657876 ACM |
43 | { |
44 | if (likely(skb != NULL)) { | |
45 | const struct inet_sock *inet = inet_sk(sk); | |
57cca05a | 46 | const struct inet_connection_sock *icsk = inet_csk(sk); |
7c657876 ACM |
47 | struct dccp_sock *dp = dccp_sk(sk); |
48 | struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb); | |
49 | struct dccp_hdr *dh; | |
50 | /* XXX For now we're using only 48 bits sequence numbers */ | |
118b2c95 | 51 | const u32 dccp_header_size = sizeof(*dh) + |
7c657876 | 52 | sizeof(struct dccp_hdr_ext) + |
7690af3f | 53 | dccp_packet_hdr_len(dcb->dccpd_type); |
7c657876 ACM |
54 | int err, set_ack = 1; |
55 | u64 ackno = dp->dccps_gsr; | |
56 | ||
7c657876 ACM |
57 | dccp_inc_seqno(&dp->dccps_gss); |
58 | ||
7c657876 ACM |
59 | switch (dcb->dccpd_type) { |
60 | case DCCP_PKT_DATA: | |
61 | set_ack = 0; | |
edc9e819 HX |
62 | /* fall through */ |
63 | case DCCP_PKT_DATAACK: | |
ee1a1592 | 64 | case DCCP_PKT_RESET: |
7c657876 | 65 | break; |
edc9e819 | 66 | |
afe00251 AB |
67 | case DCCP_PKT_REQUEST: |
68 | set_ack = 0; | |
69 | /* fall through */ | |
70 | ||
7c657876 ACM |
71 | case DCCP_PKT_SYNC: |
72 | case DCCP_PKT_SYNCACK: | |
b0d045ca | 73 | ackno = dcb->dccpd_ack_seq; |
edc9e819 HX |
74 | /* fall through */ |
75 | default: | |
76 | /* | |
ee1a1592 GR |
77 | * Set owner/destructor: some skbs are allocated via |
78 | * alloc_skb (e.g. when retransmission may happen). | |
79 | * Only Data, DataAck, and Reset packets should come | |
80 | * through here with skb->sk set. | |
edc9e819 HX |
81 | */ |
82 | WARN_ON(skb->sk); | |
83 | skb_set_owner_w(skb, sk); | |
7c657876 ACM |
84 | break; |
85 | } | |
24117727 ACM |
86 | |
87 | dcb->dccpd_seq = dp->dccps_gss; | |
2d0817d1 ACM |
88 | |
89 | if (dccp_insert_options(sk, skb)) { | |
90 | kfree_skb(skb); | |
91 | return -EPROTO; | |
92 | } | |
c9eaf173 | 93 | |
fda0fd6c | 94 | |
7c657876 | 95 | /* Build DCCP header and checksum it. */ |
9b42078e | 96 | dh = dccp_zeroed_hdr(skb, dccp_header_size); |
7c657876 ACM |
97 | dh->dccph_type = dcb->dccpd_type; |
98 | dh->dccph_sport = inet->sport; | |
99 | dh->dccph_dport = inet->dport; | |
100 | dh->dccph_doff = (dccp_header_size + dcb->dccpd_opt_len) / 4; | |
101 | dh->dccph_ccval = dcb->dccpd_ccval; | |
6f4e5fff | 102 | dh->dccph_cscov = dp->dccps_pcslen; |
7c657876 ACM |
103 | /* XXX For now we're using only 48 bits sequence numbers */ |
104 | dh->dccph_x = 1; | |
105 | ||
106 | dp->dccps_awh = dp->dccps_gss; | |
107 | dccp_hdr_set_seq(dh, dp->dccps_gss); | |
108 | if (set_ack) | |
109 | dccp_hdr_set_ack(dccp_hdr_ack_bits(skb), ackno); | |
110 | ||
111 | switch (dcb->dccpd_type) { | |
112 | case DCCP_PKT_REQUEST: | |
7690af3f | 113 | dccp_hdr_request(skb)->dccph_req_service = |
67e6b629 | 114 | dp->dccps_service; |
7c657876 ACM |
115 | break; |
116 | case DCCP_PKT_RESET: | |
7690af3f ACM |
117 | dccp_hdr_reset(skb)->dccph_reset_code = |
118 | dcb->dccpd_reset_code; | |
7c657876 ACM |
119 | break; |
120 | } | |
121 | ||
6f4e5fff | 122 | icsk->icsk_af_ops->send_check(sk, 0, skb); |
7c657876 | 123 | |
7ad07e7c | 124 | if (set_ack) |
7c657876 ACM |
125 | dccp_event_ack_sent(sk); |
126 | ||
127 | DCCP_INC_STATS(DCCP_MIB_OUTSEGS); | |
128 | ||
49c5bfaf | 129 | memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt)); |
e89862f4 | 130 | err = icsk->icsk_af_ops->queue_xmit(skb, 0); |
b9df3cb8 | 131 | return net_xmit_eval(err); |
7c657876 ACM |
132 | } |
133 | return -ENOBUFS; | |
134 | } | |
135 | ||
136 | unsigned int dccp_sync_mss(struct sock *sk, u32 pmtu) | |
137 | { | |
d83d8461 | 138 | struct inet_connection_sock *icsk = inet_csk(sk); |
7c657876 | 139 | struct dccp_sock *dp = dccp_sk(sk); |
d83d8461 | 140 | int mss_now = (pmtu - icsk->icsk_af_ops->net_header_len - |
57cca05a | 141 | sizeof(struct dccp_hdr) - sizeof(struct dccp_hdr_ext)); |
7c657876 ACM |
142 | |
143 | /* Now subtract optional transport overhead */ | |
d83d8461 | 144 | mss_now -= icsk->icsk_ext_hdr_len; |
7c657876 ACM |
145 | |
146 | /* | |
147 | * FIXME: this should come from the CCID infrastructure, where, say, | |
148 | * TFRC will say it wants TIMESTAMPS, ELAPSED time, etc, for now lets | |
149 | * put a rough estimate for NDP + TIMESTAMP + TIMESTAMP_ECHO + ELAPSED | |
150 | * TIME + TFRC_OPT_LOSS_EVENT_RATE + TFRC_OPT_RECEIVE_RATE + padding to | |
151 | * make it a multiple of 4 | |
152 | */ | |
153 | ||
154 | mss_now -= ((5 + 6 + 10 + 6 + 6 + 6 + 3) / 4) * 4; | |
155 | ||
156 | /* And store cached results */ | |
d83d8461 | 157 | icsk->icsk_pmtu_cookie = pmtu; |
7c657876 ACM |
158 | dp->dccps_mss_cache = mss_now; |
159 | ||
160 | return mss_now; | |
161 | } | |
162 | ||
f21e68ca ACM |
163 | EXPORT_SYMBOL_GPL(dccp_sync_mss); |
164 | ||
c530cfb1 ACM |
165 | void dccp_write_space(struct sock *sk) |
166 | { | |
167 | read_lock(&sk->sk_callback_lock); | |
168 | ||
169 | if (sk->sk_sleep && waitqueue_active(sk->sk_sleep)) | |
170 | wake_up_interruptible(sk->sk_sleep); | |
171 | /* Should agree with poll, otherwise some programs break */ | |
172 | if (sock_writeable(sk)) | |
173 | sk_wake_async(sk, 2, POLL_OUT); | |
174 | ||
175 | read_unlock(&sk->sk_callback_lock); | |
176 | } | |
177 | ||
d6809c12 ACM |
178 | /** |
179 | * dccp_wait_for_ccid - Wait for ccid to tell us we can send a packet | |
180 | * @sk: socket to wait for | |
d6809c12 | 181 | */ |
5cc3741d | 182 | static int dccp_wait_for_ccid(struct sock *sk, struct sk_buff *skb) |
d6809c12 ACM |
183 | { |
184 | struct dccp_sock *dp = dccp_sk(sk); | |
185 | DEFINE_WAIT(wait); | |
5cc3741d | 186 | unsigned long delay; |
d6809c12 ACM |
187 | int rc; |
188 | ||
189 | while (1) { | |
190 | prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE); | |
191 | ||
97e5848d | 192 | if (sk->sk_err) |
d6809c12 | 193 | goto do_error; |
d6809c12 ACM |
194 | if (signal_pending(current)) |
195 | goto do_interrupted; | |
196 | ||
6b57c93d | 197 | rc = ccid_hc_tx_send_packet(dp->dccps_hc_tx_ccid, sk, skb); |
d6809c12 ACM |
198 | if (rc <= 0) |
199 | break; | |
6626e362 | 200 | dccp_pr_debug("delayed send by %d msec\n", rc); |
d6809c12 | 201 | delay = msecs_to_jiffies(rc); |
d6809c12 ACM |
202 | sk->sk_write_pending++; |
203 | release_sock(sk); | |
5cc3741d | 204 | schedule_timeout(delay); |
d6809c12 ACM |
205 | lock_sock(sk); |
206 | sk->sk_write_pending--; | |
207 | } | |
208 | out: | |
209 | finish_wait(sk->sk_sleep, &wait); | |
210 | return rc; | |
211 | ||
212 | do_error: | |
213 | rc = -EPIPE; | |
214 | goto out; | |
d6809c12 | 215 | do_interrupted: |
5cc3741d | 216 | rc = -EINTR; |
d6809c12 ACM |
217 | goto out; |
218 | } | |
219 | ||
97e5848d | 220 | void dccp_write_xmit(struct sock *sk, int block) |
27258ee5 | 221 | { |
97e5848d IM |
222 | struct dccp_sock *dp = dccp_sk(sk); |
223 | struct sk_buff *skb; | |
97e5848d IM |
224 | |
225 | while ((skb = skb_peek(&sk->sk_write_queue))) { | |
6b57c93d | 226 | int err = ccid_hc_tx_send_packet(dp->dccps_hc_tx_ccid, sk, skb); |
d6809c12 | 227 | |
97e5848d IM |
228 | if (err > 0) { |
229 | if (!block) { | |
230 | sk_reset_timer(sk, &dp->dccps_xmit_timer, | |
231 | msecs_to_jiffies(err)+jiffies); | |
232 | break; | |
5cc3741d IM |
233 | } else |
234 | err = dccp_wait_for_ccid(sk, skb); | |
f6282f4d | 235 | if (err && err != -EINTR) |
59348b19 | 236 | DCCP_BUG("err=%d after dccp_wait_for_ccid", err); |
97e5848d | 237 | } |
27258ee5 | 238 | |
97e5848d IM |
239 | skb_dequeue(&sk->sk_write_queue); |
240 | if (err == 0) { | |
241 | struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb); | |
242 | const int len = skb->len; | |
27258ee5 | 243 | |
97e5848d IM |
244 | if (sk->sk_state == DCCP_PARTOPEN) { |
245 | /* See 8.1.5. Handshake Completion */ | |
246 | inet_csk_schedule_ack(sk); | |
247 | inet_csk_reset_xmit_timer(sk, ICSK_TIME_DACK, | |
27258ee5 ACM |
248 | inet_csk(sk)->icsk_rto, |
249 | DCCP_RTO_MAX); | |
97e5848d IM |
250 | dcb->dccpd_type = DCCP_PKT_DATAACK; |
251 | } else if (dccp_ack_pending(sk)) | |
252 | dcb->dccpd_type = DCCP_PKT_DATAACK; | |
253 | else | |
254 | dcb->dccpd_type = DCCP_PKT_DATA; | |
255 | ||
256 | err = dccp_transmit_skb(sk, skb); | |
257 | ccid_hc_tx_packet_sent(dp->dccps_hc_tx_ccid, sk, 0, len); | |
59348b19 GR |
258 | if (err) |
259 | DCCP_BUG("err=%d after ccid_hc_tx_packet_sent", | |
260 | err); | |
f6282f4d | 261 | } else { |
6626e362 | 262 | dccp_pr_debug("packet discarded due to err=%d\n", err); |
b08d5840 | 263 | kfree_skb(skb); |
f6282f4d | 264 | } |
97e5848d | 265 | } |
27258ee5 ACM |
266 | } |
267 | ||
7c657876 ACM |
268 | int dccp_retransmit_skb(struct sock *sk, struct sk_buff *skb) |
269 | { | |
57cca05a | 270 | if (inet_csk(sk)->icsk_af_ops->rebuild_header(sk) != 0) |
7c657876 ACM |
271 | return -EHOSTUNREACH; /* Routing failure or similar. */ |
272 | ||
273 | return dccp_transmit_skb(sk, (skb_cloned(skb) ? | |
274 | pskb_copy(skb, GFP_ATOMIC): | |
275 | skb_clone(skb, GFP_ATOMIC))); | |
276 | } | |
277 | ||
278 | struct sk_buff *dccp_make_response(struct sock *sk, struct dst_entry *dst, | |
279 | struct request_sock *req) | |
280 | { | |
281 | struct dccp_hdr *dh; | |
67e6b629 | 282 | struct dccp_request_sock *dreq; |
118b2c95 | 283 | const u32 dccp_header_size = sizeof(struct dccp_hdr) + |
7c657876 ACM |
284 | sizeof(struct dccp_hdr_ext) + |
285 | sizeof(struct dccp_hdr_response); | |
118b2c95 | 286 | struct sk_buff *skb = sock_wmalloc(sk, sk->sk_prot->max_header, 1, |
7c657876 ACM |
287 | GFP_ATOMIC); |
288 | if (skb == NULL) | |
289 | return NULL; | |
290 | ||
291 | /* Reserve space for headers. */ | |
118b2c95 | 292 | skb_reserve(skb, sk->sk_prot->max_header); |
7c657876 ACM |
293 | |
294 | skb->dst = dst_clone(dst); | |
7c657876 | 295 | |
67e6b629 | 296 | dreq = dccp_rsk(req); |
e11d9d30 GR |
297 | if (inet_rsk(req)->acked) /* increase ISS upon retransmission */ |
298 | dccp_inc_seqno(&dreq->dreq_iss); | |
7c657876 | 299 | DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_RESPONSE; |
67e6b629 | 300 | DCCP_SKB_CB(skb)->dccpd_seq = dreq->dreq_iss; |
2d0817d1 ACM |
301 | |
302 | if (dccp_insert_options(sk, skb)) { | |
303 | kfree_skb(skb); | |
304 | return NULL; | |
305 | } | |
7c657876 | 306 | |
09dbc389 | 307 | /* Build and checksum header */ |
9b42078e | 308 | dh = dccp_zeroed_hdr(skb, dccp_header_size); |
7c657876 ACM |
309 | |
310 | dh->dccph_sport = inet_sk(sk)->sport; | |
311 | dh->dccph_dport = inet_rsk(req)->rmt_port; | |
7690af3f ACM |
312 | dh->dccph_doff = (dccp_header_size + |
313 | DCCP_SKB_CB(skb)->dccpd_opt_len) / 4; | |
7c657876 ACM |
314 | dh->dccph_type = DCCP_PKT_RESPONSE; |
315 | dh->dccph_x = 1; | |
67e6b629 ACM |
316 | dccp_hdr_set_seq(dh, dreq->dreq_iss); |
317 | dccp_hdr_set_ack(dccp_hdr_ack_bits(skb), dreq->dreq_isr); | |
318 | dccp_hdr_response(skb)->dccph_resp_service = dreq->dreq_service; | |
7c657876 | 319 | |
6f4e5fff GR |
320 | dccp_csum_outgoing(skb); |
321 | ||
e11d9d30 GR |
322 | /* We use `acked' to remember that a Response was already sent. */ |
323 | inet_rsk(req)->acked = 1; | |
7c657876 ACM |
324 | DCCP_INC_STATS(DCCP_MIB_OUTSEGS); |
325 | return skb; | |
326 | } | |
327 | ||
f21e68ca ACM |
328 | EXPORT_SYMBOL_GPL(dccp_make_response); |
329 | ||
ee1a1592 | 330 | /* send Reset on established socket, to close or abort the connection */ |
017487d7 ACM |
331 | int dccp_send_reset(struct sock *sk, enum dccp_reset_codes code) |
332 | { | |
ee1a1592 | 333 | struct sk_buff *skb; |
017487d7 ACM |
334 | /* |
335 | * FIXME: what if rebuild_header fails? | |
336 | * Should we be doing a rebuild_header here? | |
337 | */ | |
338 | int err = inet_sk_rebuild_header(sk); | |
339 | ||
ee1a1592 GR |
340 | if (err != 0) |
341 | return err; | |
342 | ||
343 | skb = sock_wmalloc(sk, sk->sk_prot->max_header, 1, GFP_ATOMIC); | |
344 | if (skb == NULL) | |
345 | return -ENOBUFS; | |
346 | ||
347 | /* Reserve space for headers and prepare control bits. */ | |
348 | skb_reserve(skb, sk->sk_prot->max_header); | |
349 | DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_RESET; | |
350 | DCCP_SKB_CB(skb)->dccpd_reset_code = code; | |
017487d7 | 351 | |
ee1a1592 | 352 | return dccp_transmit_skb(sk, skb); |
017487d7 ACM |
353 | } |
354 | ||
7c657876 ACM |
355 | /* |
356 | * Do all connect socket setups that can be done AF independent. | |
357 | */ | |
358 | static inline void dccp_connect_init(struct sock *sk) | |
359 | { | |
f21e68ca | 360 | struct dccp_sock *dp = dccp_sk(sk); |
7c657876 ACM |
361 | struct dst_entry *dst = __sk_dst_get(sk); |
362 | struct inet_connection_sock *icsk = inet_csk(sk); | |
363 | ||
364 | sk->sk_err = 0; | |
365 | sock_reset_flag(sk, SOCK_DONE); | |
c9eaf173 | 366 | |
7c657876 ACM |
367 | dccp_sync_mss(sk, dst_mtu(dst)); |
368 | ||
8109b02b | 369 | /* |
f21e68ca ACM |
370 | * SWL and AWL are initially adjusted so that they are not less than |
371 | * the initial Sequence Numbers received and sent, respectively: | |
372 | * SWL := max(GSR + 1 - floor(W/4), ISR), | |
373 | * AWL := max(GSS - W' + 1, ISS). | |
374 | * These adjustments MUST be applied only at the beginning of the | |
375 | * connection. | |
8109b02b | 376 | */ |
d7f7365f | 377 | dccp_update_gss(sk, dp->dccps_iss); |
f21e68ca | 378 | dccp_set_seqno(&dp->dccps_awl, max48(dp->dccps_awl, dp->dccps_iss)); |
7c657876 | 379 | |
d7f7365f GR |
380 | /* S.GAR - greatest valid acknowledgement number received on a non-Sync; |
381 | * initialized to S.ISS (sec. 8.5) */ | |
382 | dp->dccps_gar = dp->dccps_iss; | |
383 | ||
7c657876 ACM |
384 | icsk->icsk_retransmits = 0; |
385 | } | |
386 | ||
387 | int dccp_connect(struct sock *sk) | |
388 | { | |
389 | struct sk_buff *skb; | |
390 | struct inet_connection_sock *icsk = inet_csk(sk); | |
391 | ||
392 | dccp_connect_init(sk); | |
393 | ||
118b2c95 | 394 | skb = alloc_skb(sk->sk_prot->max_header, sk->sk_allocation); |
7c657876 ACM |
395 | if (unlikely(skb == NULL)) |
396 | return -ENOBUFS; | |
397 | ||
398 | /* Reserve space for headers. */ | |
118b2c95 | 399 | skb_reserve(skb, sk->sk_prot->max_header); |
7c657876 ACM |
400 | |
401 | DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_REQUEST; | |
7c657876 | 402 | |
48918a4d | 403 | dccp_skb_entail(sk, skb); |
7c657876 ACM |
404 | dccp_transmit_skb(sk, skb_clone(skb, GFP_KERNEL)); |
405 | DCCP_INC_STATS(DCCP_MIB_ACTIVEOPENS); | |
406 | ||
407 | /* Timer for repeating the REQUEST until an answer. */ | |
27258ee5 ACM |
408 | inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS, |
409 | icsk->icsk_rto, DCCP_RTO_MAX); | |
7c657876 ACM |
410 | return 0; |
411 | } | |
412 | ||
f21e68ca ACM |
413 | EXPORT_SYMBOL_GPL(dccp_connect); |
414 | ||
7c657876 ACM |
415 | void dccp_send_ack(struct sock *sk) |
416 | { | |
417 | /* If we have been reset, we may not send again. */ | |
418 | if (sk->sk_state != DCCP_CLOSED) { | |
118b2c95 ACM |
419 | struct sk_buff *skb = alloc_skb(sk->sk_prot->max_header, |
420 | GFP_ATOMIC); | |
7c657876 ACM |
421 | |
422 | if (skb == NULL) { | |
423 | inet_csk_schedule_ack(sk); | |
424 | inet_csk(sk)->icsk_ack.ato = TCP_ATO_MIN; | |
7690af3f ACM |
425 | inet_csk_reset_xmit_timer(sk, ICSK_TIME_DACK, |
426 | TCP_DELACK_MAX, | |
427 | DCCP_RTO_MAX); | |
7c657876 ACM |
428 | return; |
429 | } | |
430 | ||
431 | /* Reserve space for headers */ | |
118b2c95 | 432 | skb_reserve(skb, sk->sk_prot->max_header); |
7c657876 | 433 | DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_ACK; |
7c657876 ACM |
434 | dccp_transmit_skb(sk, skb); |
435 | } | |
436 | } | |
437 | ||
438 | EXPORT_SYMBOL_GPL(dccp_send_ack); | |
439 | ||
727ecc5f | 440 | /* FIXME: Is this still necessary (11.3) - currently nowhere used by DCCP. */ |
7c657876 ACM |
441 | void dccp_send_delayed_ack(struct sock *sk) |
442 | { | |
443 | struct inet_connection_sock *icsk = inet_csk(sk); | |
444 | /* | |
445 | * FIXME: tune this timer. elapsed time fixes the skew, so no problem | |
446 | * with using 2s, and active senders also piggyback the ACK into a | |
447 | * DATAACK packet, so this is really for quiescent senders. | |
448 | */ | |
449 | unsigned long timeout = jiffies + 2 * HZ; | |
450 | ||
451 | /* Use new timeout only if there wasn't a older one earlier. */ | |
452 | if (icsk->icsk_ack.pending & ICSK_ACK_TIMER) { | |
453 | /* If delack timer was blocked or is about to expire, | |
454 | * send ACK now. | |
455 | * | |
456 | * FIXME: check the "about to expire" part | |
457 | */ | |
458 | if (icsk->icsk_ack.blocked) { | |
459 | dccp_send_ack(sk); | |
460 | return; | |
461 | } | |
462 | ||
463 | if (!time_before(timeout, icsk->icsk_ack.timeout)) | |
464 | timeout = icsk->icsk_ack.timeout; | |
465 | } | |
466 | icsk->icsk_ack.pending |= ICSK_ACK_SCHED | ICSK_ACK_TIMER; | |
467 | icsk->icsk_ack.timeout = timeout; | |
468 | sk_reset_timer(sk, &icsk->icsk_delack_timer, timeout); | |
469 | } | |
470 | ||
b0d045ca | 471 | void dccp_send_sync(struct sock *sk, const u64 ackno, |
e92ae93a | 472 | const enum dccp_pkt_type pkt_type) |
7c657876 ACM |
473 | { |
474 | /* | |
475 | * We are not putting this on the write queue, so | |
476 | * dccp_transmit_skb() will set the ownership to this | |
477 | * sock. | |
478 | */ | |
118b2c95 | 479 | struct sk_buff *skb = alloc_skb(sk->sk_prot->max_header, GFP_ATOMIC); |
7c657876 | 480 | |
b0d045ca | 481 | if (skb == NULL) { |
7c657876 | 482 | /* FIXME: how to make sure the sync is sent? */ |
b0d045ca | 483 | DCCP_CRIT("could not send %s", dccp_packet_name(pkt_type)); |
7c657876 | 484 | return; |
b0d045ca | 485 | } |
7c657876 ACM |
486 | |
487 | /* Reserve space for headers and prepare control bits. */ | |
118b2c95 | 488 | skb_reserve(skb, sk->sk_prot->max_header); |
e92ae93a | 489 | DCCP_SKB_CB(skb)->dccpd_type = pkt_type; |
b0d045ca | 490 | DCCP_SKB_CB(skb)->dccpd_ack_seq = ackno; |
7c657876 | 491 | |
7c657876 ACM |
492 | dccp_transmit_skb(sk, skb); |
493 | } | |
494 | ||
b61fafc4 ACM |
495 | EXPORT_SYMBOL_GPL(dccp_send_sync); |
496 | ||
7690af3f ACM |
497 | /* |
498 | * Send a DCCP_PKT_CLOSE/CLOSEREQ. The caller locks the socket for us. This | |
499 | * cannot be allowed to fail queueing a DCCP_PKT_CLOSE/CLOSEREQ frame under | |
500 | * any circumstances. | |
7c657876 | 501 | */ |
7ad07e7c | 502 | void dccp_send_close(struct sock *sk, const int active) |
7c657876 ACM |
503 | { |
504 | struct dccp_sock *dp = dccp_sk(sk); | |
505 | struct sk_buff *skb; | |
7d877f3b | 506 | const gfp_t prio = active ? GFP_KERNEL : GFP_ATOMIC; |
7c657876 | 507 | |
7ad07e7c ACM |
508 | skb = alloc_skb(sk->sk_prot->max_header, prio); |
509 | if (skb == NULL) | |
510 | return; | |
7c657876 ACM |
511 | |
512 | /* Reserve space for headers and prepare control bits. */ | |
513 | skb_reserve(skb, sk->sk_prot->max_header); | |
7690af3f ACM |
514 | DCCP_SKB_CB(skb)->dccpd_type = dp->dccps_role == DCCP_ROLE_CLIENT ? |
515 | DCCP_PKT_CLOSE : DCCP_PKT_CLOSEREQ; | |
7c657876 | 516 | |
7ad07e7c | 517 | if (active) { |
97e5848d | 518 | dccp_write_xmit(sk, 1); |
48918a4d | 519 | dccp_skb_entail(sk, skb); |
7ad07e7c | 520 | dccp_transmit_skb(sk, skb_clone(skb, prio)); |
97e5848d | 521 | /* FIXME do we need a retransmit timer here? */ |
7ad07e7c ACM |
522 | } else |
523 | dccp_transmit_skb(sk, skb); | |
7c657876 | 524 | } |