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-rw-r--r--net/dccp/options.c443
1 files changed, 9 insertions, 434 deletions
diff --git a/net/dccp/options.c b/net/dccp/options.c
index d4c4242d8dd7..0a76426c9aea 100644
--- a/net/dccp/options.c
+++ b/net/dccp/options.c
@@ -18,19 +18,15 @@
18#include <linux/kernel.h> 18#include <linux/kernel.h>
19#include <linux/skbuff.h> 19#include <linux/skbuff.h>
20 20
21#include "ackvec.h"
21#include "ccid.h" 22#include "ccid.h"
22#include "dccp.h" 23#include "dccp.h"
23 24
24static void dccp_ackpkts_check_rcv_ackvector(struct dccp_ackpkts *ap,
25 struct sock *sk,
26 const u64 ackno,
27 const unsigned char len,
28 const unsigned char *vector);
29
30/* stores the default values for new connection. may be changed with sysctl */ 25/* stores the default values for new connection. may be changed with sysctl */
31static const struct dccp_options dccpo_default_values = { 26static const struct dccp_options dccpo_default_values = {
32 .dccpo_sequence_window = DCCPF_INITIAL_SEQUENCE_WINDOW, 27 .dccpo_sequence_window = DCCPF_INITIAL_SEQUENCE_WINDOW,
33 .dccpo_ccid = DCCPF_INITIAL_CCID, 28 .dccpo_rx_ccid = DCCPF_INITIAL_CCID,
29 .dccpo_tx_ccid = DCCPF_INITIAL_CCID,
34 .dccpo_send_ack_vector = DCCPF_INITIAL_SEND_ACK_VECTOR, 30 .dccpo_send_ack_vector = DCCPF_INITIAL_SEND_ACK_VECTOR,
35 .dccpo_send_ndp_count = DCCPF_INITIAL_SEND_NDP_COUNT, 31 .dccpo_send_ndp_count = DCCPF_INITIAL_SEND_NDP_COUNT,
36}; 32};
@@ -113,25 +109,13 @@ int dccp_parse_options(struct sock *sk, struct sk_buff *skb)
113 opt_recv->dccpor_ndp); 109 opt_recv->dccpor_ndp);
114 break; 110 break;
115 case DCCPO_ACK_VECTOR_0: 111 case DCCPO_ACK_VECTOR_0:
116 if (len > DCCP_MAX_ACK_VECTOR_LEN) 112 case DCCPO_ACK_VECTOR_1:
117 goto out_invalid_option;
118
119 if (pkt_type == DCCP_PKT_DATA) 113 if (pkt_type == DCCP_PKT_DATA)
120 continue; 114 continue;
121 115
122 opt_recv->dccpor_ack_vector_len = len; 116 if (dp->dccps_options.dccpo_send_ack_vector &&
123 opt_recv->dccpor_ack_vector_idx = value - options; 117 dccp_ackvec_parse(sk, skb, opt, value, len))
124 118 goto out_invalid_option;
125 dccp_pr_debug("%sACK vector 0, len=%d, ack_ackno=%llu\n",
126 debug_prefix, len,
127 (unsigned long long)
128 DCCP_SKB_CB(skb)->dccpd_ack_seq);
129 dccp_ackvector_print(DCCP_SKB_CB(skb)->dccpd_ack_seq,
130 value, len);
131 dccp_ackpkts_check_rcv_ackvector(dp->dccps_hc_rx_ackpkts,
132 sk,
133 DCCP_SKB_CB(skb)->dccpd_ack_seq,
134 len, value);
135 break; 119 break;
136 case DCCPO_TIMESTAMP: 120 case DCCPO_TIMESTAMP:
137 if (len != 4) 121 if (len != 4)
@@ -352,86 +336,6 @@ void dccp_insert_option_elapsed_time(struct sock *sk,
352 336
353EXPORT_SYMBOL_GPL(dccp_insert_option_elapsed_time); 337EXPORT_SYMBOL_GPL(dccp_insert_option_elapsed_time);
354 338
355static void dccp_insert_option_ack_vector(struct sock *sk, struct sk_buff *skb)
356{
357 struct dccp_sock *dp = dccp_sk(sk);
358#ifdef CONFIG_IP_DCCP_DEBUG
359 const char *debug_prefix = dp->dccps_role == DCCP_ROLE_CLIENT ?
360 "CLIENT TX opt: " : "server TX opt: ";
361#endif
362 struct dccp_ackpkts *ap = dp->dccps_hc_rx_ackpkts;
363 int len = ap->dccpap_buf_vector_len + 2;
364 struct timeval now;
365 u32 elapsed_time;
366 unsigned char *to, *from;
367
368 dccp_timestamp(sk, &now);
369 elapsed_time = timeval_delta(&now, &ap->dccpap_time) / 10;
370
371 if (elapsed_time != 0)
372 dccp_insert_option_elapsed_time(sk, skb, elapsed_time);
373
374 if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN) {
375 LIMIT_NETDEBUG(KERN_INFO "DCCP: packet too small to "
376 "insert ACK Vector!\n");
377 return;
378 }
379
380 /*
381 * XXX: now we have just one ack vector sent record, so
382 * we have to wait for it to be cleared.
383 *
384 * Of course this is not acceptable, but this is just for
385 * basic testing now.
386 */
387 if (ap->dccpap_ack_seqno != DCCP_MAX_SEQNO + 1)
388 return;
389
390 DCCP_SKB_CB(skb)->dccpd_opt_len += len;
391
392 to = skb_push(skb, len);
393 *to++ = DCCPO_ACK_VECTOR_0;
394 *to++ = len;
395
396 len = ap->dccpap_buf_vector_len;
397 from = ap->dccpap_buf + ap->dccpap_buf_head;
398
399 /* Check if buf_head wraps */
400 if (ap->dccpap_buf_head + len > ap->dccpap_buf_len) {
401 const unsigned int tailsize = (ap->dccpap_buf_len -
402 ap->dccpap_buf_head);
403
404 memcpy(to, from, tailsize);
405 to += tailsize;
406 len -= tailsize;
407 from = ap->dccpap_buf;
408 }
409
410 memcpy(to, from, len);
411 /*
412 * From draft-ietf-dccp-spec-11.txt:
413 *
414 * For each acknowledgement it sends, the HC-Receiver will add an
415 * acknowledgement record. ack_seqno will equal the HC-Receiver
416 * sequence number it used for the ack packet; ack_ptr will equal
417 * buf_head; ack_ackno will equal buf_ackno; and ack_nonce will
418 * equal buf_nonce.
419 *
420 * This implemention uses just one ack record for now.
421 */
422 ap->dccpap_ack_seqno = DCCP_SKB_CB(skb)->dccpd_seq;
423 ap->dccpap_ack_ptr = ap->dccpap_buf_head;
424 ap->dccpap_ack_ackno = ap->dccpap_buf_ackno;
425 ap->dccpap_ack_nonce = ap->dccpap_buf_nonce;
426 ap->dccpap_ack_vector_len = ap->dccpap_buf_vector_len;
427
428 dccp_pr_debug("%sACK Vector 0, len=%d, ack_seqno=%llu, "
429 "ack_ackno=%llu\n",
430 debug_prefix, ap->dccpap_ack_vector_len,
431 (unsigned long long) ap->dccpap_ack_seqno,
432 (unsigned long long) ap->dccpap_ack_ackno);
433}
434
435void dccp_timestamp(const struct sock *sk, struct timeval *tv) 339void dccp_timestamp(const struct sock *sk, struct timeval *tv)
436{ 340{
437 const struct dccp_sock *dp = dccp_sk(sk); 341 const struct dccp_sock *dp = dccp_sk(sk);
@@ -528,9 +432,8 @@ void dccp_insert_options(struct sock *sk, struct sk_buff *skb)
528 432
529 if (!dccp_packet_without_ack(skb)) { 433 if (!dccp_packet_without_ack(skb)) {
530 if (dp->dccps_options.dccpo_send_ack_vector && 434 if (dp->dccps_options.dccpo_send_ack_vector &&
531 (dp->dccps_hc_rx_ackpkts->dccpap_buf_ackno != 435 dccp_ackvec_pending(dp->dccps_hc_rx_ackvec))
532 DCCP_MAX_SEQNO + 1)) 436 dccp_insert_option_ackvec(sk, skb);
533 dccp_insert_option_ack_vector(sk, skb);
534 if (dp->dccps_timestamp_echo != 0) 437 if (dp->dccps_timestamp_echo != 0)
535 dccp_insert_option_timestamp_echo(sk, skb); 438 dccp_insert_option_timestamp_echo(sk, skb);
536 } 439 }
@@ -557,331 +460,3 @@ void dccp_insert_options(struct sock *sk, struct sk_buff *skb)
557 } 460 }
558 } 461 }
559} 462}
560
561struct dccp_ackpkts *dccp_ackpkts_alloc(const unsigned int len,
562 const unsigned int __nocast priority)
563{
564 struct dccp_ackpkts *ap = kmalloc(sizeof(*ap) + len, priority);
565
566 if (ap != NULL) {
567#ifdef CONFIG_IP_DCCP_DEBUG
568 memset(ap->dccpap_buf, 0xFF, len);
569#endif
570 ap->dccpap_buf_len = len;
571 ap->dccpap_buf_head =
572 ap->dccpap_buf_tail =
573 ap->dccpap_buf_len - 1;
574 ap->dccpap_buf_ackno =
575 ap->dccpap_ack_ackno =
576 ap->dccpap_ack_seqno = DCCP_MAX_SEQNO + 1;
577 ap->dccpap_buf_nonce = ap->dccpap_buf_nonce = 0;
578 ap->dccpap_ack_ptr = 0;
579 ap->dccpap_time.tv_sec = 0;
580 ap->dccpap_time.tv_usec = 0;
581 ap->dccpap_buf_vector_len = ap->dccpap_ack_vector_len = 0;
582 }
583
584 return ap;
585}
586
587void dccp_ackpkts_free(struct dccp_ackpkts *ap)
588{
589 if (ap != NULL) {
590#ifdef CONFIG_IP_DCCP_DEBUG
591 memset(ap, 0xFF, sizeof(*ap) + ap->dccpap_buf_len);
592#endif
593 kfree(ap);
594 }
595}
596
597static inline u8 dccp_ackpkts_state(const struct dccp_ackpkts *ap,
598 const unsigned int index)
599{
600 return ap->dccpap_buf[index] & DCCP_ACKPKTS_STATE_MASK;
601}
602
603static inline u8 dccp_ackpkts_len(const struct dccp_ackpkts *ap,
604 const unsigned int index)
605{
606 return ap->dccpap_buf[index] & DCCP_ACKPKTS_LEN_MASK;
607}
608
609/*
610 * If several packets are missing, the HC-Receiver may prefer to enter multiple
611 * bytes with run length 0, rather than a single byte with a larger run length;
612 * this simplifies table updates if one of the missing packets arrives.
613 */
614static inline int dccp_ackpkts_set_buf_head_state(struct dccp_ackpkts *ap,
615 const unsigned int packets,
616 const unsigned char state)
617{
618 unsigned int gap;
619 signed long new_head;
620
621 if (ap->dccpap_buf_vector_len + packets > ap->dccpap_buf_len)
622 return -ENOBUFS;
623
624 gap = packets - 1;
625 new_head = ap->dccpap_buf_head - packets;
626
627 if (new_head < 0) {
628 if (gap > 0) {
629 memset(ap->dccpap_buf, DCCP_ACKPKTS_STATE_NOT_RECEIVED,
630 gap + new_head + 1);
631 gap = -new_head;
632 }
633 new_head += ap->dccpap_buf_len;
634 }
635
636 ap->dccpap_buf_head = new_head;
637
638 if (gap > 0)
639 memset(ap->dccpap_buf + ap->dccpap_buf_head + 1,
640 DCCP_ACKPKTS_STATE_NOT_RECEIVED, gap);
641
642 ap->dccpap_buf[ap->dccpap_buf_head] = state;
643 ap->dccpap_buf_vector_len += packets;
644 return 0;
645}
646
647/*
648 * Implements the draft-ietf-dccp-spec-11.txt Appendix A
649 */
650int dccp_ackpkts_add(struct dccp_ackpkts *ap, const struct sock *sk,
651 u64 ackno, u8 state)
652{
653 /*
654 * Check at the right places if the buffer is full, if it is, tell the
655 * caller to start dropping packets till the HC-Sender acks our ACK
656 * vectors, when we will free up space in dccpap_buf.
657 *
658 * We may well decide to do buffer compression, etc, but for now lets
659 * just drop.
660 *
661 * From Appendix A:
662 *
663 * Of course, the circular buffer may overflow, either when the
664 * HC-Sender is sending data at a very high rate, when the
665 * HC-Receiver's acknowledgements are not reaching the HC-Sender,
666 * or when the HC-Sender is forgetting to acknowledge those acks
667 * (so the HC-Receiver is unable to clean up old state). In this
668 * case, the HC-Receiver should either compress the buffer (by
669 * increasing run lengths when possible), transfer its state to
670 * a larger buffer, or, as a last resort, drop all received
671 * packets, without processing them whatsoever, until its buffer
672 * shrinks again.
673 */
674
675 /* See if this is the first ackno being inserted */
676 if (ap->dccpap_buf_vector_len == 0) {
677 ap->dccpap_buf[ap->dccpap_buf_head] = state;
678 ap->dccpap_buf_vector_len = 1;
679 } else if (after48(ackno, ap->dccpap_buf_ackno)) {
680 const u64 delta = dccp_delta_seqno(ap->dccpap_buf_ackno,
681 ackno);
682
683 /*
684 * Look if the state of this packet is the same as the
685 * previous ackno and if so if we can bump the head len.
686 */
687 if (delta == 1 &&
688 dccp_ackpkts_state(ap, ap->dccpap_buf_head) == state &&
689 (dccp_ackpkts_len(ap, ap->dccpap_buf_head) <
690 DCCP_ACKPKTS_LEN_MASK))
691 ap->dccpap_buf[ap->dccpap_buf_head]++;
692 else if (dccp_ackpkts_set_buf_head_state(ap, delta, state))
693 return -ENOBUFS;
694 } else {
695 /*
696 * A.1.2. Old Packets
697 *
698 * When a packet with Sequence Number S arrives, and
699 * S <= buf_ackno, the HC-Receiver will scan the table
700 * for the byte corresponding to S. (Indexing structures
701 * could reduce the complexity of this scan.)
702 */
703 u64 delta = dccp_delta_seqno(ackno, ap->dccpap_buf_ackno);
704 unsigned int index = ap->dccpap_buf_head;
705
706 while (1) {
707 const u8 len = dccp_ackpkts_len(ap, index);
708 const u8 state = dccp_ackpkts_state(ap, index);
709 /*
710 * valid packets not yet in dccpap_buf have a reserved
711 * entry, with a len equal to 0.
712 */
713 if (state == DCCP_ACKPKTS_STATE_NOT_RECEIVED &&
714 len == 0 && delta == 0) { /* Found our
715 reserved seat! */
716 dccp_pr_debug("Found %llu reserved seat!\n",
717 (unsigned long long) ackno);
718 ap->dccpap_buf[index] = state;
719 goto out;
720 }
721 /* len == 0 means one packet */
722 if (delta < len + 1)
723 goto out_duplicate;
724
725 delta -= len + 1;
726 if (++index == ap->dccpap_buf_len)
727 index = 0;
728 }
729 }
730
731 ap->dccpap_buf_ackno = ackno;
732 dccp_timestamp(sk, &ap->dccpap_time);
733out:
734 dccp_pr_debug("");
735 dccp_ackpkts_print(ap);
736 return 0;
737
738out_duplicate:
739 /* Duplicate packet */
740 dccp_pr_debug("Received a dup or already considered lost "
741 "packet: %llu\n", (unsigned long long) ackno);
742 return -EILSEQ;
743}
744
745#ifdef CONFIG_IP_DCCP_DEBUG
746void dccp_ackvector_print(const u64 ackno, const unsigned char *vector,
747 int len)
748{
749 if (!dccp_debug)
750 return;
751
752 printk("ACK vector len=%d, ackno=%llu |", len,
753 (unsigned long long) ackno);
754
755 while (len--) {
756 const u8 state = (*vector & DCCP_ACKPKTS_STATE_MASK) >> 6;
757 const u8 rl = (*vector & DCCP_ACKPKTS_LEN_MASK);
758
759 printk("%d,%d|", state, rl);
760 ++vector;
761 }
762
763 printk("\n");
764}
765
766void dccp_ackpkts_print(const struct dccp_ackpkts *ap)
767{
768 dccp_ackvector_print(ap->dccpap_buf_ackno,
769 ap->dccpap_buf + ap->dccpap_buf_head,
770 ap->dccpap_buf_vector_len);
771}
772#endif
773
774static void dccp_ackpkts_trow_away_ack_record(struct dccp_ackpkts *ap)
775{
776 /*
777 * As we're keeping track of the ack vector size
778 * (dccpap_buf_vector_len) and the sent ack vector size
779 * (dccpap_ack_vector_len) we don't need dccpap_buf_tail at all, but
780 * keep this code here as in the future we'll implement a vector of
781 * ack records, as suggested in draft-ietf-dccp-spec-11.txt
782 * Appendix A. -acme
783 */
784#if 0
785 ap->dccpap_buf_tail = ap->dccpap_ack_ptr + 1;
786 if (ap->dccpap_buf_tail >= ap->dccpap_buf_len)
787 ap->dccpap_buf_tail -= ap->dccpap_buf_len;
788#endif
789 ap->dccpap_buf_vector_len -= ap->dccpap_ack_vector_len;
790}
791
792void dccp_ackpkts_check_rcv_ackno(struct dccp_ackpkts *ap, struct sock *sk,
793 u64 ackno)
794{
795 /* Check if we actually sent an ACK vector */
796 if (ap->dccpap_ack_seqno == DCCP_MAX_SEQNO + 1)
797 return;
798
799 if (ackno == ap->dccpap_ack_seqno) {
800#ifdef CONFIG_IP_DCCP_DEBUG
801 struct dccp_sock *dp = dccp_sk(sk);
802 const char *debug_prefix = dp->dccps_role == DCCP_ROLE_CLIENT ?
803 "CLIENT rx ack: " : "server rx ack: ";
804#endif
805 dccp_pr_debug("%sACK packet 0, len=%d, ack_seqno=%llu, "
806 "ack_ackno=%llu, ACKED!\n",
807 debug_prefix, 1,
808 (unsigned long long) ap->dccpap_ack_seqno,
809 (unsigned long long) ap->dccpap_ack_ackno);
810 dccp_ackpkts_trow_away_ack_record(ap);
811 ap->dccpap_ack_seqno = DCCP_MAX_SEQNO + 1;
812 }
813}
814
815static void dccp_ackpkts_check_rcv_ackvector(struct dccp_ackpkts *ap,
816 struct sock *sk, u64 ackno,
817 const unsigned char len,
818 const unsigned char *vector)
819{
820 unsigned char i;
821
822 /* Check if we actually sent an ACK vector */
823 if (ap->dccpap_ack_seqno == DCCP_MAX_SEQNO + 1)
824 return;
825 /*
826 * We're in the receiver half connection, so if the received an ACK
827 * vector ackno (e.g. 50) before dccpap_ack_seqno (e.g. 52), we're
828 * not interested.
829 *
830 * Extra explanation with example:
831 *
832 * if we received an ACK vector with ackno 50, it can only be acking
833 * 50, 49, 48, etc, not 52 (the seqno for the ACK vector we sent).
834 */
835 /* dccp_pr_debug("is %llu < %llu? ", ackno, ap->dccpap_ack_seqno); */
836 if (before48(ackno, ap->dccpap_ack_seqno)) {
837 /* dccp_pr_debug_cat("yes\n"); */
838 return;
839 }
840 /* dccp_pr_debug_cat("no\n"); */
841
842 i = len;
843 while (i--) {
844 const u8 rl = (*vector & DCCP_ACKPKTS_LEN_MASK);
845 u64 ackno_end_rl;
846
847 dccp_set_seqno(&ackno_end_rl, ackno - rl);
848
849 /*
850 * dccp_pr_debug("is %llu <= %llu <= %llu? ", ackno_end_rl,
851 * ap->dccpap_ack_seqno, ackno);
852 */
853 if (between48(ap->dccpap_ack_seqno, ackno_end_rl, ackno)) {
854 const u8 state = (*vector &
855 DCCP_ACKPKTS_STATE_MASK) >> 6;
856 /* dccp_pr_debug_cat("yes\n"); */
857
858 if (state != DCCP_ACKPKTS_STATE_NOT_RECEIVED) {
859#ifdef CONFIG_IP_DCCP_DEBUG
860 struct dccp_sock *dp = dccp_sk(sk);
861 const char *debug_prefix =
862 dp->dccps_role == DCCP_ROLE_CLIENT ?
863 "CLIENT rx ack: " : "server rx ack: ";
864#endif
865 dccp_pr_debug("%sACK vector 0, len=%d, "
866 "ack_seqno=%llu, ack_ackno=%llu, "
867 "ACKED!\n",
868 debug_prefix, len,
869 (unsigned long long)
870 ap->dccpap_ack_seqno,
871 (unsigned long long)
872 ap->dccpap_ack_ackno);
873 dccp_ackpkts_trow_away_ack_record(ap);
874 }
875 /*
876 * If dccpap_ack_seqno was not received, no problem
877 * we'll send another ACK vector.
878 */
879 ap->dccpap_ack_seqno = DCCP_MAX_SEQNO + 1;
880 break;
881 }
882 /* dccp_pr_debug_cat("no\n"); */
883
884 dccp_set_seqno(&ackno, ackno_end_rl - 1);
885 ++vector;
886 }
887}
generated by cgit v1.2.2 (git 2.25.0) at 2025-11-07 10:21:37 -0500