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34
35#include "../dccp.h"
36#include "ccid3.h"
37
38#include <asm/unaligned.h>
39
40#ifdef CONFIG_IP_DCCP_CCID3_DEBUG
41static bool ccid3_debug;
42#define ccid3_pr_debug(format, a...) DCCP_PR_DEBUG(ccid3_debug, format, ##a)
43#else
44#define ccid3_pr_debug(format, a...)
45#endif
46
47
48
49
50#ifdef CONFIG_IP_DCCP_CCID3_DEBUG
51static const char *ccid3_tx_state_name(enum ccid3_hc_tx_states state)
52{
53 static const char *const ccid3_state_names[] = {
54 [TFRC_SSTATE_NO_SENT] = "NO_SENT",
55 [TFRC_SSTATE_NO_FBACK] = "NO_FBACK",
56 [TFRC_SSTATE_FBACK] = "FBACK",
57 };
58
59 return ccid3_state_names[state];
60}
61#endif
62
63static void ccid3_hc_tx_set_state(struct sock *sk,
64 enum ccid3_hc_tx_states state)
65{
66 struct ccid3_hc_tx_sock *hc = ccid3_hc_tx_sk(sk);
67 enum ccid3_hc_tx_states oldstate = hc->tx_state;
68
69 ccid3_pr_debug("%s(%p) %-8.8s -> %s\n",
70 dccp_role(sk), sk, ccid3_tx_state_name(oldstate),
71 ccid3_tx_state_name(state));
72 WARN_ON(state == oldstate);
73 hc->tx_state = state;
74}
75
76
77
78
79
80
81
82
83
84
85static inline u64 rfc3390_initial_rate(struct sock *sk)
86{
87 const struct ccid3_hc_tx_sock *hc = ccid3_hc_tx_sk(sk);
88 const __u32 w_init = clamp_t(__u32, 4380U, 2 * hc->tx_s, 4 * hc->tx_s);
89
90 return scaled_div(w_init << 6, hc->tx_rtt);
91}
92
93
94
95
96
97static void ccid3_update_send_interval(struct ccid3_hc_tx_sock *hc)
98{
99 hc->tx_t_ipi = scaled_div32(((u64)hc->tx_s) << 6, hc->tx_x);
100
101 DCCP_BUG_ON(hc->tx_t_ipi == 0);
102 ccid3_pr_debug("t_ipi=%u, s=%u, X=%u\n", hc->tx_t_ipi,
103 hc->tx_s, (unsigned int)(hc->tx_x >> 6));
104}
105
106static u32 ccid3_hc_tx_idle_rtt(struct ccid3_hc_tx_sock *hc, ktime_t now)
107{
108 u32 delta = ktime_us_delta(now, hc->tx_t_last_win_count);
109
110 return delta / hc->tx_rtt;
111}
112
113
114
115
116
117
118
119
120
121
122
123
124static void ccid3_hc_tx_update_x(struct sock *sk, ktime_t *stamp)
125{
126 struct ccid3_hc_tx_sock *hc = ccid3_hc_tx_sk(sk);
127 __u64 min_rate = 2 * hc->tx_x_recv;
128 const __u64 old_x = hc->tx_x;
129 ktime_t now = stamp ? *stamp : ktime_get_real();
130
131
132
133
134
135
136
137 if (ccid3_hc_tx_idle_rtt(hc, now) >= 2) {
138 min_rate = rfc3390_initial_rate(sk);
139 min_rate = max(min_rate, 2 * hc->tx_x_recv);
140 }
141
142 if (hc->tx_p > 0) {
143
144 hc->tx_x = min(((__u64)hc->tx_x_calc) << 6, min_rate);
145 hc->tx_x = max(hc->tx_x, (((__u64)hc->tx_s) << 6) / TFRC_T_MBI);
146
147 } else if (ktime_us_delta(now, hc->tx_t_ld) - (s64)hc->tx_rtt >= 0) {
148
149 hc->tx_x = min(2 * hc->tx_x, min_rate);
150 hc->tx_x = max(hc->tx_x,
151 scaled_div(((__u64)hc->tx_s) << 6, hc->tx_rtt));
152 hc->tx_t_ld = now;
153 }
154
155 if (hc->tx_x != old_x) {
156 ccid3_pr_debug("X_prev=%u, X_now=%u, X_calc=%u, "
157 "X_recv=%u\n", (unsigned int)(old_x >> 6),
158 (unsigned int)(hc->tx_x >> 6), hc->tx_x_calc,
159 (unsigned int)(hc->tx_x_recv >> 6));
160
161 ccid3_update_send_interval(hc);
162 }
163}
164
165
166
167
168
169
170
171static inline void ccid3_hc_tx_update_s(struct ccid3_hc_tx_sock *hc, int len)
172{
173 const u16 old_s = hc->tx_s;
174
175 hc->tx_s = tfrc_ewma(hc->tx_s, len, 9);
176
177 if (hc->tx_s != old_s)
178 ccid3_update_send_interval(hc);
179}
180
181
182
183
184
185static inline void ccid3_hc_tx_update_win_count(struct ccid3_hc_tx_sock *hc,
186 ktime_t now)
187{
188 u32 delta = ktime_us_delta(now, hc->tx_t_last_win_count),
189 quarter_rtts = (4 * delta) / hc->tx_rtt;
190
191 if (quarter_rtts > 0) {
192 hc->tx_t_last_win_count = now;
193 hc->tx_last_win_count += min(quarter_rtts, 5U);
194 hc->tx_last_win_count &= 0xF;
195 }
196}
197
198static void ccid3_hc_tx_no_feedback_timer(struct timer_list *t)
199{
200 struct ccid3_hc_tx_sock *hc = from_timer(hc, t, tx_no_feedback_timer);
201 struct sock *sk = hc->sk;
202 unsigned long t_nfb = USEC_PER_SEC / 5;
203
204 bh_lock_sock(sk);
205 if (sock_owned_by_user(sk)) {
206
207
208 goto restart_timer;
209 }
210
211 ccid3_pr_debug("%s(%p, state=%s) - entry\n", dccp_role(sk), sk,
212 ccid3_tx_state_name(hc->tx_state));
213
214
215 if ((1 << sk->sk_state) & ~(DCCPF_OPEN | DCCPF_PARTOPEN))
216 goto out;
217
218
219 if (hc->tx_state == TFRC_SSTATE_FBACK)
220 ccid3_hc_tx_set_state(sk, TFRC_SSTATE_NO_FBACK);
221
222
223
224
225
226 if (hc->tx_t_rto == 0 || hc->tx_p == 0) {
227
228
229 hc->tx_x = max(hc->tx_x / 2,
230 (((__u64)hc->tx_s) << 6) / TFRC_T_MBI);
231 ccid3_update_send_interval(hc);
232 } else {
233
234
235
236
237
238
239
240
241
242
243 if (hc->tx_x_calc > (hc->tx_x_recv >> 5))
244 hc->tx_x_recv =
245 max(hc->tx_x_recv / 2,
246 (((__u64)hc->tx_s) << 6) / (2*TFRC_T_MBI));
247 else {
248 hc->tx_x_recv = hc->tx_x_calc;
249 hc->tx_x_recv <<= 4;
250 }
251 ccid3_hc_tx_update_x(sk, NULL);
252 }
253 ccid3_pr_debug("Reduced X to %llu/64 bytes/sec\n",
254 (unsigned long long)hc->tx_x);
255
256
257
258
259
260 if (unlikely(hc->tx_t_rto == 0))
261 t_nfb = TFRC_INITIAL_TIMEOUT;
262 else
263 t_nfb = max(hc->tx_t_rto, 2 * hc->tx_t_ipi);
264
265restart_timer:
266 sk_reset_timer(sk, &hc->tx_no_feedback_timer,
267 jiffies + usecs_to_jiffies(t_nfb));
268out:
269 bh_unlock_sock(sk);
270 sock_put(sk);
271}
272
273
274
275
276
277
278
279
280static int ccid3_hc_tx_send_packet(struct sock *sk, struct sk_buff *skb)
281{
282 struct dccp_sock *dp = dccp_sk(sk);
283 struct ccid3_hc_tx_sock *hc = ccid3_hc_tx_sk(sk);
284 ktime_t now = ktime_get_real();
285 s64 delay;
286
287
288
289
290
291
292 if (unlikely(skb->len == 0))
293 return -EBADMSG;
294
295 if (hc->tx_state == TFRC_SSTATE_NO_SENT) {
296 sk_reset_timer(sk, &hc->tx_no_feedback_timer, (jiffies +
297 usecs_to_jiffies(TFRC_INITIAL_TIMEOUT)));
298 hc->tx_last_win_count = 0;
299 hc->tx_t_last_win_count = now;
300
301
302 hc->tx_t_nom = now;
303
304 hc->tx_s = skb->len;
305
306
307
308
309
310
311 if (dp->dccps_syn_rtt) {
312 ccid3_pr_debug("SYN RTT = %uus\n", dp->dccps_syn_rtt);
313 hc->tx_rtt = dp->dccps_syn_rtt;
314 hc->tx_x = rfc3390_initial_rate(sk);
315 hc->tx_t_ld = now;
316 } else {
317
318
319
320
321
322
323 hc->tx_rtt = DCCP_FALLBACK_RTT;
324 hc->tx_x = hc->tx_s;
325 hc->tx_x <<= 6;
326 }
327 ccid3_update_send_interval(hc);
328
329 ccid3_hc_tx_set_state(sk, TFRC_SSTATE_NO_FBACK);
330
331 } else {
332 delay = ktime_us_delta(hc->tx_t_nom, now);
333 ccid3_pr_debug("delay=%ld\n", (long)delay);
334
335
336
337
338
339
340
341
342 if (delay >= TFRC_T_DELTA)
343 return (u32)delay / USEC_PER_MSEC;
344
345 ccid3_hc_tx_update_win_count(hc, now);
346 }
347
348
349 dp->dccps_hc_tx_insert_options = 1;
350 DCCP_SKB_CB(skb)->dccpd_ccval = hc->tx_last_win_count;
351
352
353 hc->tx_t_nom = ktime_add_us(hc->tx_t_nom, hc->tx_t_ipi);
354 return CCID_PACKET_SEND_AT_ONCE;
355}
356
357static void ccid3_hc_tx_packet_sent(struct sock *sk, unsigned int len)
358{
359 struct ccid3_hc_tx_sock *hc = ccid3_hc_tx_sk(sk);
360
361 ccid3_hc_tx_update_s(hc, len);
362
363 if (tfrc_tx_hist_add(&hc->tx_hist, dccp_sk(sk)->dccps_gss))
364 DCCP_CRIT("packet history - out of memory!");
365}
366
367static void ccid3_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb)
368{
369 struct ccid3_hc_tx_sock *hc = ccid3_hc_tx_sk(sk);
370 struct tfrc_tx_hist_entry *acked;
371 ktime_t now;
372 unsigned long t_nfb;
373 u32 r_sample;
374
375
376 if (!(DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_ACK ||
377 DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_DATAACK))
378 return;
379
380
381
382
383
384
385
386
387 acked = tfrc_tx_hist_find_entry(hc->tx_hist, dccp_hdr_ack_seq(skb));
388 if (acked == NULL)
389 return;
390
391 tfrc_tx_hist_purge(&acked->next);
392
393
394 now = ktime_get_real();
395 r_sample = dccp_sample_rtt(sk, ktime_us_delta(now, acked->stamp));
396 hc->tx_rtt = tfrc_ewma(hc->tx_rtt, r_sample, 9);
397
398
399
400
401 if (hc->tx_state == TFRC_SSTATE_NO_FBACK) {
402 ccid3_hc_tx_set_state(sk, TFRC_SSTATE_FBACK);
403
404 if (hc->tx_t_rto == 0) {
405
406
407
408 hc->tx_x = rfc3390_initial_rate(sk);
409 hc->tx_t_ld = now;
410
411 ccid3_update_send_interval(hc);
412
413 goto done_computing_x;
414 } else if (hc->tx_p == 0) {
415
416
417
418 goto done_computing_x;
419 }
420 }
421
422
423 if (hc->tx_p > 0)
424 hc->tx_x_calc = tfrc_calc_x(hc->tx_s, hc->tx_rtt, hc->tx_p);
425 ccid3_hc_tx_update_x(sk, &now);
426
427done_computing_x:
428 ccid3_pr_debug("%s(%p), RTT=%uus (sample=%uus), s=%u, "
429 "p=%u, X_calc=%u, X_recv=%u, X=%u\n",
430 dccp_role(sk), sk, hc->tx_rtt, r_sample,
431 hc->tx_s, hc->tx_p, hc->tx_x_calc,
432 (unsigned int)(hc->tx_x_recv >> 6),
433 (unsigned int)(hc->tx_x >> 6));
434
435
436 sk_stop_timer(sk, &hc->tx_no_feedback_timer);
437
438
439
440
441
442 sk->sk_write_space(sk);
443
444
445
446
447
448
449 hc->tx_t_rto = max_t(u32, 4 * hc->tx_rtt,
450 USEC_PER_SEC/HZ * tcp_rto_min(sk));
451
452
453
454
455 t_nfb = max(hc->tx_t_rto, 2 * hc->tx_t_ipi);
456
457 ccid3_pr_debug("%s(%p), Scheduled no feedback timer to "
458 "expire in %lu jiffies (%luus)\n",
459 dccp_role(sk), sk, usecs_to_jiffies(t_nfb), t_nfb);
460
461 sk_reset_timer(sk, &hc->tx_no_feedback_timer,
462 jiffies + usecs_to_jiffies(t_nfb));
463}
464
465static int ccid3_hc_tx_parse_options(struct sock *sk, u8 packet_type,
466 u8 option, u8 *optval, u8 optlen)
467{
468 struct ccid3_hc_tx_sock *hc = ccid3_hc_tx_sk(sk);
469 __be32 opt_val;
470
471 switch (option) {
472 case TFRC_OPT_RECEIVE_RATE:
473 case TFRC_OPT_LOSS_EVENT_RATE:
474
475 if (packet_type == DCCP_PKT_DATA)
476 break;
477 if (unlikely(optlen != 4)) {
478 DCCP_WARN("%s(%p), invalid len %d for %u\n",
479 dccp_role(sk), sk, optlen, option);
480 return -EINVAL;
481 }
482 opt_val = ntohl(get_unaligned((__be32 *)optval));
483
484 if (option == TFRC_OPT_RECEIVE_RATE) {
485
486 hc->tx_x_recv = opt_val;
487 hc->tx_x_recv <<= 6;
488
489 ccid3_pr_debug("%s(%p), RECEIVE_RATE=%u\n",
490 dccp_role(sk), sk, opt_val);
491 } else {
492
493 hc->tx_p = tfrc_invert_loss_event_rate(opt_val);
494
495 ccid3_pr_debug("%s(%p), LOSS_EVENT_RATE=%u\n",
496 dccp_role(sk), sk, opt_val);
497 }
498 }
499 return 0;
500}
501
502static int ccid3_hc_tx_init(struct ccid *ccid, struct sock *sk)
503{
504 struct ccid3_hc_tx_sock *hc = ccid_priv(ccid);
505
506 hc->tx_state = TFRC_SSTATE_NO_SENT;
507 hc->tx_hist = NULL;
508 hc->sk = sk;
509 timer_setup(&hc->tx_no_feedback_timer,
510 ccid3_hc_tx_no_feedback_timer, 0);
511 return 0;
512}
513
514static void ccid3_hc_tx_exit(struct sock *sk)
515{
516 struct ccid3_hc_tx_sock *hc = ccid3_hc_tx_sk(sk);
517
518 sk_stop_timer(sk, &hc->tx_no_feedback_timer);
519 tfrc_tx_hist_purge(&hc->tx_hist);
520}
521
522static void ccid3_hc_tx_get_info(struct sock *sk, struct tcp_info *info)
523{
524 info->tcpi_rto = ccid3_hc_tx_sk(sk)->tx_t_rto;
525 info->tcpi_rtt = ccid3_hc_tx_sk(sk)->tx_rtt;
526}
527
528static int ccid3_hc_tx_getsockopt(struct sock *sk, const int optname, int len,
529 u32 __user *optval, int __user *optlen)
530{
531 const struct ccid3_hc_tx_sock *hc = ccid3_hc_tx_sk(sk);
532 struct tfrc_tx_info tfrc;
533 const void *val;
534
535 switch (optname) {
536 case DCCP_SOCKOPT_CCID_TX_INFO:
537 if (len < sizeof(tfrc))
538 return -EINVAL;
539 memset(&tfrc, 0, sizeof(tfrc));
540 tfrc.tfrctx_x = hc->tx_x;
541 tfrc.tfrctx_x_recv = hc->tx_x_recv;
542 tfrc.tfrctx_x_calc = hc->tx_x_calc;
543 tfrc.tfrctx_rtt = hc->tx_rtt;
544 tfrc.tfrctx_p = hc->tx_p;
545 tfrc.tfrctx_rto = hc->tx_t_rto;
546 tfrc.tfrctx_ipi = hc->tx_t_ipi;
547 len = sizeof(tfrc);
548 val = &tfrc;
549 break;
550 default:
551 return -ENOPROTOOPT;
552 }
553
554 if (put_user(len, optlen) || copy_to_user(optval, val, len))
555 return -EFAULT;
556
557 return 0;
558}
559
560
561
562
563
564
565enum ccid3_fback_type {
566 CCID3_FBACK_NONE = 0,
567 CCID3_FBACK_INITIAL,
568 CCID3_FBACK_PERIODIC,
569 CCID3_FBACK_PARAM_CHANGE
570};
571
572#ifdef CONFIG_IP_DCCP_CCID3_DEBUG
573static const char *ccid3_rx_state_name(enum ccid3_hc_rx_states state)
574{
575 static const char *const ccid3_rx_state_names[] = {
576 [TFRC_RSTATE_NO_DATA] = "NO_DATA",
577 [TFRC_RSTATE_DATA] = "DATA",
578 };
579
580 return ccid3_rx_state_names[state];
581}
582#endif
583
584static void ccid3_hc_rx_set_state(struct sock *sk,
585 enum ccid3_hc_rx_states state)
586{
587 struct ccid3_hc_rx_sock *hc = ccid3_hc_rx_sk(sk);
588 enum ccid3_hc_rx_states oldstate = hc->rx_state;
589
590 ccid3_pr_debug("%s(%p) %-8.8s -> %s\n",
591 dccp_role(sk), sk, ccid3_rx_state_name(oldstate),
592 ccid3_rx_state_name(state));
593 WARN_ON(state == oldstate);
594 hc->rx_state = state;
595}
596
597static void ccid3_hc_rx_send_feedback(struct sock *sk,
598 const struct sk_buff *skb,
599 enum ccid3_fback_type fbtype)
600{
601 struct ccid3_hc_rx_sock *hc = ccid3_hc_rx_sk(sk);
602 struct dccp_sock *dp = dccp_sk(sk);
603 ktime_t now = ktime_get_real();
604 s64 delta = 0;
605
606 switch (fbtype) {
607 case CCID3_FBACK_INITIAL:
608 hc->rx_x_recv = 0;
609 hc->rx_pinv = ~0U;
610 break;
611 case CCID3_FBACK_PARAM_CHANGE:
612
613
614
615
616
617
618
619
620
621
622 if (hc->rx_x_recv > 0)
623 break;
624
625 case CCID3_FBACK_PERIODIC:
626 delta = ktime_us_delta(now, hc->rx_tstamp_last_feedback);
627 if (delta <= 0)
628 DCCP_BUG("delta (%ld) <= 0", (long)delta);
629 else
630 hc->rx_x_recv = scaled_div32(hc->rx_bytes_recv, delta);
631 break;
632 default:
633 return;
634 }
635
636 ccid3_pr_debug("Interval %ldusec, X_recv=%u, 1/p=%u\n", (long)delta,
637 hc->rx_x_recv, hc->rx_pinv);
638
639 hc->rx_tstamp_last_feedback = now;
640 hc->rx_last_counter = dccp_hdr(skb)->dccph_ccval;
641 hc->rx_bytes_recv = 0;
642
643 dp->dccps_hc_rx_insert_options = 1;
644 dccp_send_ack(sk);
645}
646
647static int ccid3_hc_rx_insert_options(struct sock *sk, struct sk_buff *skb)
648{
649 const struct ccid3_hc_rx_sock *hc = ccid3_hc_rx_sk(sk);
650 __be32 x_recv, pinv;
651
652 if (!(sk->sk_state == DCCP_OPEN || sk->sk_state == DCCP_PARTOPEN))
653 return 0;
654
655 if (dccp_packet_without_ack(skb))
656 return 0;
657
658 x_recv = htonl(hc->rx_x_recv);
659 pinv = htonl(hc->rx_pinv);
660
661 if (dccp_insert_option(skb, TFRC_OPT_LOSS_EVENT_RATE,
662 &pinv, sizeof(pinv)) ||
663 dccp_insert_option(skb, TFRC_OPT_RECEIVE_RATE,
664 &x_recv, sizeof(x_recv)))
665 return -1;
666
667 return 0;
668}
669
670
671
672
673
674
675
676
677
678
679
680static u32 ccid3_first_li(struct sock *sk)
681{
682 struct ccid3_hc_rx_sock *hc = ccid3_hc_rx_sk(sk);
683 u32 x_recv, p, delta;
684 u64 fval;
685
686 if (hc->rx_rtt == 0) {
687 DCCP_WARN("No RTT estimate available, using fallback RTT\n");
688 hc->rx_rtt = DCCP_FALLBACK_RTT;
689 }
690
691 delta = ktime_to_us(net_timedelta(hc->rx_tstamp_last_feedback));
692 x_recv = scaled_div32(hc->rx_bytes_recv, delta);
693 if (x_recv == 0) {
694 DCCP_WARN("X_recv==0\n");
695 if (hc->rx_x_recv == 0) {
696 DCCP_BUG("stored value of X_recv is zero");
697 return ~0U;
698 }
699 x_recv = hc->rx_x_recv;
700 }
701
702 fval = scaled_div(hc->rx_s, hc->rx_rtt);
703 fval = scaled_div32(fval, x_recv);
704 p = tfrc_calc_x_reverse_lookup(fval);
705
706 ccid3_pr_debug("%s(%p), receive rate=%u bytes/s, implied "
707 "loss rate=%u\n", dccp_role(sk), sk, x_recv, p);
708
709 return p == 0 ? ~0U : scaled_div(1, p);
710}
711
712static void ccid3_hc_rx_packet_recv(struct sock *sk, struct sk_buff *skb)
713{
714 struct ccid3_hc_rx_sock *hc = ccid3_hc_rx_sk(sk);
715 enum ccid3_fback_type do_feedback = CCID3_FBACK_NONE;
716 const u64 ndp = dccp_sk(sk)->dccps_options_received.dccpor_ndp;
717 const bool is_data_packet = dccp_data_packet(skb);
718
719 if (unlikely(hc->rx_state == TFRC_RSTATE_NO_DATA)) {
720 if (is_data_packet) {
721 const u32 payload = skb->len - dccp_hdr(skb)->dccph_doff * 4;
722 do_feedback = CCID3_FBACK_INITIAL;
723 ccid3_hc_rx_set_state(sk, TFRC_RSTATE_DATA);
724 hc->rx_s = payload;
725
726
727
728
729
730 }
731 goto update_records;
732 }
733
734 if (tfrc_rx_hist_duplicate(&hc->rx_hist, skb))
735 return;
736
737 if (is_data_packet) {
738 const u32 payload = skb->len - dccp_hdr(skb)->dccph_doff * 4;
739
740
741
742 hc->rx_s = tfrc_ewma(hc->rx_s, payload, 9);
743 hc->rx_bytes_recv += payload;
744 }
745
746
747
748
749 if (tfrc_rx_handle_loss(&hc->rx_hist, &hc->rx_li_hist,
750 skb, ndp, ccid3_first_li, sk)) {
751 do_feedback = CCID3_FBACK_PARAM_CHANGE;
752 goto done_receiving;
753 }
754
755 if (tfrc_rx_hist_loss_pending(&hc->rx_hist))
756 return;
757
758
759
760
761 if (unlikely(!is_data_packet))
762 goto update_records;
763
764 if (!tfrc_lh_is_initialised(&hc->rx_li_hist)) {
765 const u32 sample = tfrc_rx_hist_sample_rtt(&hc->rx_hist, skb);
766
767
768
769
770
771 if (sample != 0)
772 hc->rx_rtt = tfrc_ewma(hc->rx_rtt, sample, 9);
773
774 } else if (tfrc_lh_update_i_mean(&hc->rx_li_hist, skb)) {
775
776
777
778
779 do_feedback = CCID3_FBACK_PARAM_CHANGE;
780 }
781
782
783
784
785 if (SUB16(dccp_hdr(skb)->dccph_ccval, hc->rx_last_counter) > 3)
786 do_feedback = CCID3_FBACK_PERIODIC;
787
788update_records:
789 tfrc_rx_hist_add_packet(&hc->rx_hist, skb, ndp);
790
791done_receiving:
792 if (do_feedback)
793 ccid3_hc_rx_send_feedback(sk, skb, do_feedback);
794}
795
796static int ccid3_hc_rx_init(struct ccid *ccid, struct sock *sk)
797{
798 struct ccid3_hc_rx_sock *hc = ccid_priv(ccid);
799
800 hc->rx_state = TFRC_RSTATE_NO_DATA;
801 tfrc_lh_init(&hc->rx_li_hist);
802 return tfrc_rx_hist_alloc(&hc->rx_hist);
803}
804
805static void ccid3_hc_rx_exit(struct sock *sk)
806{
807 struct ccid3_hc_rx_sock *hc = ccid3_hc_rx_sk(sk);
808
809 tfrc_rx_hist_purge(&hc->rx_hist);
810 tfrc_lh_cleanup(&hc->rx_li_hist);
811}
812
813static void ccid3_hc_rx_get_info(struct sock *sk, struct tcp_info *info)
814{
815 info->tcpi_ca_state = ccid3_hc_rx_sk(sk)->rx_state;
816 info->tcpi_options |= TCPI_OPT_TIMESTAMPS;
817 info->tcpi_rcv_rtt = ccid3_hc_rx_sk(sk)->rx_rtt;
818}
819
820static int ccid3_hc_rx_getsockopt(struct sock *sk, const int optname, int len,
821 u32 __user *optval, int __user *optlen)
822{
823 const struct ccid3_hc_rx_sock *hc = ccid3_hc_rx_sk(sk);
824 struct tfrc_rx_info rx_info;
825 const void *val;
826
827 switch (optname) {
828 case DCCP_SOCKOPT_CCID_RX_INFO:
829 if (len < sizeof(rx_info))
830 return -EINVAL;
831 rx_info.tfrcrx_x_recv = hc->rx_x_recv;
832 rx_info.tfrcrx_rtt = hc->rx_rtt;
833 rx_info.tfrcrx_p = tfrc_invert_loss_event_rate(hc->rx_pinv);
834 len = sizeof(rx_info);
835 val = &rx_info;
836 break;
837 default:
838 return -ENOPROTOOPT;
839 }
840
841 if (put_user(len, optlen) || copy_to_user(optval, val, len))
842 return -EFAULT;
843
844 return 0;
845}
846
847struct ccid_operations ccid3_ops = {
848 .ccid_id = DCCPC_CCID3,
849 .ccid_name = "TCP-Friendly Rate Control",
850 .ccid_hc_tx_obj_size = sizeof(struct ccid3_hc_tx_sock),
851 .ccid_hc_tx_init = ccid3_hc_tx_init,
852 .ccid_hc_tx_exit = ccid3_hc_tx_exit,
853 .ccid_hc_tx_send_packet = ccid3_hc_tx_send_packet,
854 .ccid_hc_tx_packet_sent = ccid3_hc_tx_packet_sent,
855 .ccid_hc_tx_packet_recv = ccid3_hc_tx_packet_recv,
856 .ccid_hc_tx_parse_options = ccid3_hc_tx_parse_options,
857 .ccid_hc_rx_obj_size = sizeof(struct ccid3_hc_rx_sock),
858 .ccid_hc_rx_init = ccid3_hc_rx_init,
859 .ccid_hc_rx_exit = ccid3_hc_rx_exit,
860 .ccid_hc_rx_insert_options = ccid3_hc_rx_insert_options,
861 .ccid_hc_rx_packet_recv = ccid3_hc_rx_packet_recv,
862 .ccid_hc_rx_get_info = ccid3_hc_rx_get_info,
863 .ccid_hc_tx_get_info = ccid3_hc_tx_get_info,
864 .ccid_hc_rx_getsockopt = ccid3_hc_rx_getsockopt,
865 .ccid_hc_tx_getsockopt = ccid3_hc_tx_getsockopt,
866};
867
868#ifdef CONFIG_IP_DCCP_CCID3_DEBUG
869module_param(ccid3_debug, bool, 0644);
870MODULE_PARM_DESC(ccid3_debug, "Enable CCID-3 debug messages");
871#endif
872