147505b8bSThomas Gleixner // SPDX-License-Identifier: GPL-2.0-or-later
260c778b2SVlad Yasevich /* SCTP kernel implementation
31da177e4SLinus Torvalds * (C) Copyright IBM Corp. 2001, 2004
41da177e4SLinus Torvalds * Copyright (c) 1999-2000 Cisco, Inc.
51da177e4SLinus Torvalds * Copyright (c) 1999-2001 Motorola, Inc.
61da177e4SLinus Torvalds * Copyright (c) 2001-2003 Intel Corp.
71da177e4SLinus Torvalds *
860c778b2SVlad Yasevich * This file is part of the SCTP kernel implementation
91da177e4SLinus Torvalds *
101da177e4SLinus Torvalds * These functions implement the sctp_outq class. The outqueue handles
111da177e4SLinus Torvalds * bundling and queueing of outgoing SCTP chunks.
121da177e4SLinus Torvalds *
131da177e4SLinus Torvalds * Please send any bug reports or fixes you make to the
141da177e4SLinus Torvalds * email address(es):
1591705c61SDaniel Borkmann * lksctp developers <linux-sctp@vger.kernel.org>
161da177e4SLinus Torvalds *
171da177e4SLinus Torvalds * Written or modified by:
181da177e4SLinus Torvalds * La Monte H.P. Yarroll <piggy@acm.org>
191da177e4SLinus Torvalds * Karl Knutson <karl@athena.chicago.il.us>
201da177e4SLinus Torvalds * Perry Melange <pmelange@null.cc.uic.edu>
211da177e4SLinus Torvalds * Xingang Guo <xingang.guo@intel.com>
221da177e4SLinus Torvalds * Hui Huang <hui.huang@nokia.com>
231da177e4SLinus Torvalds * Sridhar Samudrala <sri@us.ibm.com>
241da177e4SLinus Torvalds * Jon Grimm <jgrimm@us.ibm.com>
251da177e4SLinus Torvalds */
261da177e4SLinus Torvalds
27145ce502SJoe Perches #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
28145ce502SJoe Perches
291da177e4SLinus Torvalds #include <linux/types.h>
301da177e4SLinus Torvalds #include <linux/list.h> /* For struct list_head */
311da177e4SLinus Torvalds #include <linux/socket.h>
321da177e4SLinus Torvalds #include <linux/ip.h>
335a0e3ad6STejun Heo #include <linux/slab.h>
341da177e4SLinus Torvalds #include <net/sock.h> /* For skb_set_owner_w */
351da177e4SLinus Torvalds
361da177e4SLinus Torvalds #include <net/sctp/sctp.h>
371da177e4SLinus Torvalds #include <net/sctp/sm.h>
385bbbbe32SMarcelo Ricardo Leitner #include <net/sctp/stream_sched.h>
39f643ee29SKevin Kou #include <trace/events/sctp.h>
401da177e4SLinus Torvalds
411da177e4SLinus Torvalds /* Declare internal functions here. */
421da177e4SLinus Torvalds static int sctp_acked(struct sctp_sackhdr *sack, __u32 tsn);
431da177e4SLinus Torvalds static void sctp_check_transmitted(struct sctp_outq *q,
441da177e4SLinus Torvalds struct list_head *transmitted_queue,
451da177e4SLinus Torvalds struct sctp_transport *transport,
46edfee033SNicolas Dichtel union sctp_addr *saddr,
471da177e4SLinus Torvalds struct sctp_sackhdr *sack,
48bfa0d984SVlad Yasevich __u32 *highest_new_tsn);
491da177e4SLinus Torvalds
501da177e4SLinus Torvalds static void sctp_mark_missing(struct sctp_outq *q,
511da177e4SLinus Torvalds struct list_head *transmitted_queue,
521da177e4SLinus Torvalds struct sctp_transport *transport,
531da177e4SLinus Torvalds __u32 highest_new_tsn,
541da177e4SLinus Torvalds int count_of_newacks);
551da177e4SLinus Torvalds
5683dbc3d4SXin Long static void sctp_outq_flush(struct sctp_outq *q, int rtx_timeout, gfp_t gfp);
57abd0b198SAdrian Bunk
581da177e4SLinus Torvalds /* Add data to the front of the queue. */
sctp_outq_head_data(struct sctp_outq * q,struct sctp_chunk * ch)591da177e4SLinus Torvalds static inline void sctp_outq_head_data(struct sctp_outq *q,
601da177e4SLinus Torvalds struct sctp_chunk *ch)
611da177e4SLinus Torvalds {
625bbbbe32SMarcelo Ricardo Leitner struct sctp_stream_out_ext *oute;
635bbbbe32SMarcelo Ricardo Leitner __u16 stream;
645bbbbe32SMarcelo Ricardo Leitner
6579af02c2SDavid S. Miller list_add(&ch->list, &q->out_chunk_list);
661da177e4SLinus Torvalds q->out_qlen += ch->skb->len;
675bbbbe32SMarcelo Ricardo Leitner
685bbbbe32SMarcelo Ricardo Leitner stream = sctp_chunk_stream_no(ch);
6905364ca0SKonstantin Khorenko oute = SCTP_SO(&q->asoc->stream, stream)->ext;
705bbbbe32SMarcelo Ricardo Leitner list_add(&ch->stream_list, &oute->outq);
711da177e4SLinus Torvalds }
721da177e4SLinus Torvalds
731da177e4SLinus Torvalds /* Take data from the front of the queue. */
sctp_outq_dequeue_data(struct sctp_outq * q)741da177e4SLinus Torvalds static inline struct sctp_chunk *sctp_outq_dequeue_data(struct sctp_outq *q)
751da177e4SLinus Torvalds {
765bbbbe32SMarcelo Ricardo Leitner return q->sched->dequeue(q);
7779af02c2SDavid S. Miller }
785bbbbe32SMarcelo Ricardo Leitner
791da177e4SLinus Torvalds /* Add data chunk to the end of the queue. */
sctp_outq_tail_data(struct sctp_outq * q,struct sctp_chunk * ch)801da177e4SLinus Torvalds static inline void sctp_outq_tail_data(struct sctp_outq *q,
811da177e4SLinus Torvalds struct sctp_chunk *ch)
821da177e4SLinus Torvalds {
835bbbbe32SMarcelo Ricardo Leitner struct sctp_stream_out_ext *oute;
845bbbbe32SMarcelo Ricardo Leitner __u16 stream;
855bbbbe32SMarcelo Ricardo Leitner
8679af02c2SDavid S. Miller list_add_tail(&ch->list, &q->out_chunk_list);
871da177e4SLinus Torvalds q->out_qlen += ch->skb->len;
885bbbbe32SMarcelo Ricardo Leitner
895bbbbe32SMarcelo Ricardo Leitner stream = sctp_chunk_stream_no(ch);
9005364ca0SKonstantin Khorenko oute = SCTP_SO(&q->asoc->stream, stream)->ext;
915bbbbe32SMarcelo Ricardo Leitner list_add_tail(&ch->stream_list, &oute->outq);
921da177e4SLinus Torvalds }
931da177e4SLinus Torvalds
941da177e4SLinus Torvalds /*
951da177e4SLinus Torvalds * SFR-CACC algorithm:
961da177e4SLinus Torvalds * D) If count_of_newacks is greater than or equal to 2
971da177e4SLinus Torvalds * and t was not sent to the current primary then the
981da177e4SLinus Torvalds * sender MUST NOT increment missing report count for t.
991da177e4SLinus Torvalds */
sctp_cacc_skip_3_1_d(struct sctp_transport * primary,struct sctp_transport * transport,int count_of_newacks)1001da177e4SLinus Torvalds static inline int sctp_cacc_skip_3_1_d(struct sctp_transport *primary,
1011da177e4SLinus Torvalds struct sctp_transport *transport,
1021da177e4SLinus Torvalds int count_of_newacks)
1031da177e4SLinus Torvalds {
1041da177e4SLinus Torvalds if (count_of_newacks >= 2 && transport != primary)
1051da177e4SLinus Torvalds return 1;
1061da177e4SLinus Torvalds return 0;
1071da177e4SLinus Torvalds }
1081da177e4SLinus Torvalds
1091da177e4SLinus Torvalds /*
1101da177e4SLinus Torvalds * SFR-CACC algorithm:
1111da177e4SLinus Torvalds * F) If count_of_newacks is less than 2, let d be the
1121da177e4SLinus Torvalds * destination to which t was sent. If cacc_saw_newack
1131da177e4SLinus Torvalds * is 0 for destination d, then the sender MUST NOT
1141da177e4SLinus Torvalds * increment missing report count for t.
1151da177e4SLinus Torvalds */
sctp_cacc_skip_3_1_f(struct sctp_transport * transport,int count_of_newacks)1161da177e4SLinus Torvalds static inline int sctp_cacc_skip_3_1_f(struct sctp_transport *transport,
1171da177e4SLinus Torvalds int count_of_newacks)
1181da177e4SLinus Torvalds {
119f246a7b7SVlad Yasevich if (count_of_newacks < 2 &&
120f246a7b7SVlad Yasevich (transport && !transport->cacc.cacc_saw_newack))
1211da177e4SLinus Torvalds return 1;
1221da177e4SLinus Torvalds return 0;
1231da177e4SLinus Torvalds }
1241da177e4SLinus Torvalds
1251da177e4SLinus Torvalds /*
1261da177e4SLinus Torvalds * SFR-CACC algorithm:
1271da177e4SLinus Torvalds * 3.1) If CYCLING_CHANGEOVER is 0, the sender SHOULD
1281da177e4SLinus Torvalds * execute steps C, D, F.
1291da177e4SLinus Torvalds *
1301da177e4SLinus Torvalds * C has been implemented in sctp_outq_sack
1311da177e4SLinus Torvalds */
sctp_cacc_skip_3_1(struct sctp_transport * primary,struct sctp_transport * transport,int count_of_newacks)1321da177e4SLinus Torvalds static inline int sctp_cacc_skip_3_1(struct sctp_transport *primary,
1331da177e4SLinus Torvalds struct sctp_transport *transport,
1341da177e4SLinus Torvalds int count_of_newacks)
1351da177e4SLinus Torvalds {
1361da177e4SLinus Torvalds if (!primary->cacc.cycling_changeover) {
1371da177e4SLinus Torvalds if (sctp_cacc_skip_3_1_d(primary, transport, count_of_newacks))
1381da177e4SLinus Torvalds return 1;
1391da177e4SLinus Torvalds if (sctp_cacc_skip_3_1_f(transport, count_of_newacks))
1401da177e4SLinus Torvalds return 1;
1411da177e4SLinus Torvalds return 0;
1421da177e4SLinus Torvalds }
1431da177e4SLinus Torvalds return 0;
1441da177e4SLinus Torvalds }
1451da177e4SLinus Torvalds
1461da177e4SLinus Torvalds /*
1471da177e4SLinus Torvalds * SFR-CACC algorithm:
1481da177e4SLinus Torvalds * 3.2) Else if CYCLING_CHANGEOVER is 1, and t is less
1491da177e4SLinus Torvalds * than next_tsn_at_change of the current primary, then
1501da177e4SLinus Torvalds * the sender MUST NOT increment missing report count
1511da177e4SLinus Torvalds * for t.
1521da177e4SLinus Torvalds */
sctp_cacc_skip_3_2(struct sctp_transport * primary,__u32 tsn)1531da177e4SLinus Torvalds static inline int sctp_cacc_skip_3_2(struct sctp_transport *primary, __u32 tsn)
1541da177e4SLinus Torvalds {
1551da177e4SLinus Torvalds if (primary->cacc.cycling_changeover &&
1561da177e4SLinus Torvalds TSN_lt(tsn, primary->cacc.next_tsn_at_change))
1571da177e4SLinus Torvalds return 1;
1581da177e4SLinus Torvalds return 0;
1591da177e4SLinus Torvalds }
1601da177e4SLinus Torvalds
1611da177e4SLinus Torvalds /*
1621da177e4SLinus Torvalds * SFR-CACC algorithm:
1631da177e4SLinus Torvalds * 3) If the missing report count for TSN t is to be
1641da177e4SLinus Torvalds * incremented according to [RFC2960] and
1651da177e4SLinus Torvalds * [SCTP_STEWART-2002], and CHANGEOVER_ACTIVE is set,
16625985edcSLucas De Marchi * then the sender MUST further execute steps 3.1 and
1671da177e4SLinus Torvalds * 3.2 to determine if the missing report count for
1681da177e4SLinus Torvalds * TSN t SHOULD NOT be incremented.
1691da177e4SLinus Torvalds *
1701da177e4SLinus Torvalds * 3.3) If 3.1 and 3.2 do not dictate that the missing
1711da177e4SLinus Torvalds * report count for t should not be incremented, then
17225985edcSLucas De Marchi * the sender SHOULD increment missing report count for
1731da177e4SLinus Torvalds * t (according to [RFC2960] and [SCTP_STEWART_2002]).
1741da177e4SLinus Torvalds */
sctp_cacc_skip(struct sctp_transport * primary,struct sctp_transport * transport,int count_of_newacks,__u32 tsn)1751da177e4SLinus Torvalds static inline int sctp_cacc_skip(struct sctp_transport *primary,
1761da177e4SLinus Torvalds struct sctp_transport *transport,
1771da177e4SLinus Torvalds int count_of_newacks,
1781da177e4SLinus Torvalds __u32 tsn)
1791da177e4SLinus Torvalds {
1801da177e4SLinus Torvalds if (primary->cacc.changeover_active &&
181f64f9e71SJoe Perches (sctp_cacc_skip_3_1(primary, transport, count_of_newacks) ||
182f64f9e71SJoe Perches sctp_cacc_skip_3_2(primary, tsn)))
1831da177e4SLinus Torvalds return 1;
1841da177e4SLinus Torvalds return 0;
1851da177e4SLinus Torvalds }
1861da177e4SLinus Torvalds
1871da177e4SLinus Torvalds /* Initialize an existing sctp_outq. This does the boring stuff.
1881da177e4SLinus Torvalds * You still need to define handlers if you really want to DO
1891da177e4SLinus Torvalds * something with this structure...
1901da177e4SLinus Torvalds */
sctp_outq_init(struct sctp_association * asoc,struct sctp_outq * q)1911da177e4SLinus Torvalds void sctp_outq_init(struct sctp_association *asoc, struct sctp_outq *q)
1921da177e4SLinus Torvalds {
193c5c7774dSNeil Horman memset(q, 0, sizeof(struct sctp_outq));
194c5c7774dSNeil Horman
1951da177e4SLinus Torvalds q->asoc = asoc;
19679af02c2SDavid S. Miller INIT_LIST_HEAD(&q->out_chunk_list);
19779af02c2SDavid S. Miller INIT_LIST_HEAD(&q->control_chunk_list);
1981da177e4SLinus Torvalds INIT_LIST_HEAD(&q->retransmit);
1991da177e4SLinus Torvalds INIT_LIST_HEAD(&q->sacked);
2001da177e4SLinus Torvalds INIT_LIST_HEAD(&q->abandoned);
2017efba10dSXin Long sctp_sched_set_sched(asoc, sctp_sk(asoc->base.sk)->default_ss);
2021da177e4SLinus Torvalds }
2031da177e4SLinus Torvalds
2041da177e4SLinus Torvalds /* Free the outqueue structure and any related pending chunks.
2051da177e4SLinus Torvalds */
__sctp_outq_teardown(struct sctp_outq * q)2062f94aabdSNeil Horman static void __sctp_outq_teardown(struct sctp_outq *q)
2071da177e4SLinus Torvalds {
2081da177e4SLinus Torvalds struct sctp_transport *transport;
2099dbc15f0SRobert P. J. Day struct list_head *lchunk, *temp;
21079af02c2SDavid S. Miller struct sctp_chunk *chunk, *tmp;
2111da177e4SLinus Torvalds
2121da177e4SLinus Torvalds /* Throw away unacknowledged chunks. */
2139dbc15f0SRobert P. J. Day list_for_each_entry(transport, &q->asoc->peer.transport_addr_list,
2149dbc15f0SRobert P. J. Day transports) {
2151da177e4SLinus Torvalds while ((lchunk = sctp_list_dequeue(&transport->transmitted)) != NULL) {
2161da177e4SLinus Torvalds chunk = list_entry(lchunk, struct sctp_chunk,
2171da177e4SLinus Torvalds transmitted_list);
2181da177e4SLinus Torvalds /* Mark as part of a failed message. */
2191da177e4SLinus Torvalds sctp_chunk_fail(chunk, q->error);
2201da177e4SLinus Torvalds sctp_chunk_free(chunk);
2211da177e4SLinus Torvalds }
2221da177e4SLinus Torvalds }
2231da177e4SLinus Torvalds
2241da177e4SLinus Torvalds /* Throw away chunks that have been gap ACKed. */
2251da177e4SLinus Torvalds list_for_each_safe(lchunk, temp, &q->sacked) {
2261da177e4SLinus Torvalds list_del_init(lchunk);
2271da177e4SLinus Torvalds chunk = list_entry(lchunk, struct sctp_chunk,
2281da177e4SLinus Torvalds transmitted_list);
2291da177e4SLinus Torvalds sctp_chunk_fail(chunk, q->error);
2301da177e4SLinus Torvalds sctp_chunk_free(chunk);
2311da177e4SLinus Torvalds }
2321da177e4SLinus Torvalds
2331da177e4SLinus Torvalds /* Throw away any chunks in the retransmit queue. */
2341da177e4SLinus Torvalds list_for_each_safe(lchunk, temp, &q->retransmit) {
2351da177e4SLinus Torvalds list_del_init(lchunk);
2361da177e4SLinus Torvalds chunk = list_entry(lchunk, struct sctp_chunk,
2371da177e4SLinus Torvalds transmitted_list);
2381da177e4SLinus Torvalds sctp_chunk_fail(chunk, q->error);
2391da177e4SLinus Torvalds sctp_chunk_free(chunk);
2401da177e4SLinus Torvalds }
2411da177e4SLinus Torvalds
2421da177e4SLinus Torvalds /* Throw away any chunks that are in the abandoned queue. */
2431da177e4SLinus Torvalds list_for_each_safe(lchunk, temp, &q->abandoned) {
2441da177e4SLinus Torvalds list_del_init(lchunk);
2451da177e4SLinus Torvalds chunk = list_entry(lchunk, struct sctp_chunk,
2461da177e4SLinus Torvalds transmitted_list);
2471da177e4SLinus Torvalds sctp_chunk_fail(chunk, q->error);
2481da177e4SLinus Torvalds sctp_chunk_free(chunk);
2491da177e4SLinus Torvalds }
2501da177e4SLinus Torvalds
2511da177e4SLinus Torvalds /* Throw away any leftover data chunks. */
2521da177e4SLinus Torvalds while ((chunk = sctp_outq_dequeue_data(q)) != NULL) {
2535bbbbe32SMarcelo Ricardo Leitner sctp_sched_dequeue_done(q, chunk);
2541da177e4SLinus Torvalds
2551da177e4SLinus Torvalds /* Mark as send failure. */
2561da177e4SLinus Torvalds sctp_chunk_fail(chunk, q->error);
2571da177e4SLinus Torvalds sctp_chunk_free(chunk);
2581da177e4SLinus Torvalds }
2591da177e4SLinus Torvalds
2601da177e4SLinus Torvalds /* Throw away any leftover control chunks. */
26179af02c2SDavid S. Miller list_for_each_entry_safe(chunk, tmp, &q->control_chunk_list, list) {
26279af02c2SDavid S. Miller list_del_init(&chunk->list);
2631da177e4SLinus Torvalds sctp_chunk_free(chunk);
2641da177e4SLinus Torvalds }
26579af02c2SDavid S. Miller }
2661da177e4SLinus Torvalds
sctp_outq_teardown(struct sctp_outq * q)2672f94aabdSNeil Horman void sctp_outq_teardown(struct sctp_outq *q)
2682f94aabdSNeil Horman {
2692f94aabdSNeil Horman __sctp_outq_teardown(q);
2702f94aabdSNeil Horman sctp_outq_init(q->asoc, q);
2712f94aabdSNeil Horman }
2722f94aabdSNeil Horman
2731da177e4SLinus Torvalds /* Free the outqueue structure and any related pending chunks. */
sctp_outq_free(struct sctp_outq * q)2741da177e4SLinus Torvalds void sctp_outq_free(struct sctp_outq *q)
2751da177e4SLinus Torvalds {
2761da177e4SLinus Torvalds /* Throw away leftover chunks. */
2772f94aabdSNeil Horman __sctp_outq_teardown(q);
2781da177e4SLinus Torvalds }
2791da177e4SLinus Torvalds
2801da177e4SLinus Torvalds /* Put a new chunk in an sctp_outq. */
sctp_outq_tail(struct sctp_outq * q,struct sctp_chunk * chunk,gfp_t gfp)28183dbc3d4SXin Long void sctp_outq_tail(struct sctp_outq *q, struct sctp_chunk *chunk, gfp_t gfp)
2821da177e4SLinus Torvalds {
2834e7696d9SXin Long struct net *net = q->asoc->base.net;
2841da177e4SLinus Torvalds
285bb33381dSDaniel Borkmann pr_debug("%s: outq:%p, chunk:%p[%s]\n", __func__, q, chunk,
286bb33381dSDaniel Borkmann chunk && chunk->chunk_hdr ?
287bb33381dSDaniel Borkmann sctp_cname(SCTP_ST_CHUNK(chunk->chunk_hdr->type)) :
288bb33381dSDaniel Borkmann "illegal chunk");
2891da177e4SLinus Torvalds
2901da177e4SLinus Torvalds /* If it is data, queue it up, otherwise, send it
2911da177e4SLinus Torvalds * immediately.
2921da177e4SLinus Torvalds */
293ec7b9519SShan Wei if (sctp_chunk_is_data(chunk)) {
294bb33381dSDaniel Borkmann pr_debug("%s: outqueueing: outq:%p, chunk:%p[%s])\n",
295bb33381dSDaniel Borkmann __func__, q, chunk, chunk && chunk->chunk_hdr ?
296bb33381dSDaniel Borkmann sctp_cname(SCTP_ST_CHUNK(chunk->chunk_hdr->type)) :
297bb33381dSDaniel Borkmann "illegal chunk");
2981da177e4SLinus Torvalds
2991da177e4SLinus Torvalds sctp_outq_tail_data(q, chunk);
300be4947bfSXin Long if (chunk->asoc->peer.prsctp_capable &&
3018dbdf1f5SXin Long SCTP_PR_PRIO_ENABLED(chunk->sinfo.sinfo_flags))
3028dbdf1f5SXin Long chunk->asoc->sent_cnt_removable++;
3031da177e4SLinus Torvalds if (chunk->chunk_hdr->flags & SCTP_DATA_UNORDERED)
304b01a2407SEric W. Biederman SCTP_INC_STATS(net, SCTP_MIB_OUTUNORDERCHUNKS);
3051da177e4SLinus Torvalds else
306b01a2407SEric W. Biederman SCTP_INC_STATS(net, SCTP_MIB_OUTORDERCHUNKS);
3071da177e4SLinus Torvalds } else {
30879af02c2SDavid S. Miller list_add_tail(&chunk->list, &q->control_chunk_list);
309b01a2407SEric W. Biederman SCTP_INC_STATS(net, SCTP_MIB_OUTCTRLCHUNKS);
3101da177e4SLinus Torvalds }
3111da177e4SLinus Torvalds
3121da177e4SLinus Torvalds if (!q->cork)
31383dbc3d4SXin Long sctp_outq_flush(q, 0, gfp);
3141da177e4SLinus Torvalds }
3151da177e4SLinus Torvalds
3161da177e4SLinus Torvalds /* Insert a chunk into the sorted list based on the TSNs. The retransmit list
3171da177e4SLinus Torvalds * and the abandoned list are in ascending order.
3181da177e4SLinus Torvalds */
sctp_insert_list(struct list_head * head,struct list_head * new)3191da177e4SLinus Torvalds static void sctp_insert_list(struct list_head *head, struct list_head *new)
3201da177e4SLinus Torvalds {
3211da177e4SLinus Torvalds struct list_head *pos;
3221da177e4SLinus Torvalds struct sctp_chunk *nchunk, *lchunk;
3231da177e4SLinus Torvalds __u32 ntsn, ltsn;
3241da177e4SLinus Torvalds int done = 0;
3251da177e4SLinus Torvalds
3261da177e4SLinus Torvalds nchunk = list_entry(new, struct sctp_chunk, transmitted_list);
3271da177e4SLinus Torvalds ntsn = ntohl(nchunk->subh.data_hdr->tsn);
3281da177e4SLinus Torvalds
3291da177e4SLinus Torvalds list_for_each(pos, head) {
3301da177e4SLinus Torvalds lchunk = list_entry(pos, struct sctp_chunk, transmitted_list);
3311da177e4SLinus Torvalds ltsn = ntohl(lchunk->subh.data_hdr->tsn);
3321da177e4SLinus Torvalds if (TSN_lt(ntsn, ltsn)) {
3331da177e4SLinus Torvalds list_add(new, pos->prev);
3341da177e4SLinus Torvalds done = 1;
3351da177e4SLinus Torvalds break;
3361da177e4SLinus Torvalds }
3371da177e4SLinus Torvalds }
3381da177e4SLinus Torvalds if (!done)
3391da177e4SLinus Torvalds list_add_tail(new, head);
3401da177e4SLinus Torvalds }
3411da177e4SLinus Torvalds
sctp_prsctp_prune_sent(struct sctp_association * asoc,struct sctp_sndrcvinfo * sinfo,struct list_head * queue,int msg_len)3428dbdf1f5SXin Long static int sctp_prsctp_prune_sent(struct sctp_association *asoc,
3438dbdf1f5SXin Long struct sctp_sndrcvinfo *sinfo,
3448dbdf1f5SXin Long struct list_head *queue, int msg_len)
3458dbdf1f5SXin Long {
3468dbdf1f5SXin Long struct sctp_chunk *chk, *temp;
3478dbdf1f5SXin Long
3488dbdf1f5SXin Long list_for_each_entry_safe(chk, temp, queue, transmitted_list) {
349d229d48dSXin Long struct sctp_stream_out *streamout;
350d229d48dSXin Long
351e5f61296SXin Long if (!chk->msg->abandoned &&
352e5f61296SXin Long (!SCTP_PR_PRIO_ENABLED(chk->sinfo.sinfo_flags) ||
353e5f61296SXin Long chk->sinfo.sinfo_timetolive <= sinfo->sinfo_timetolive))
3548dbdf1f5SXin Long continue;
3558dbdf1f5SXin Long
356e5f61296SXin Long chk->msg->abandoned = 1;
3578dbdf1f5SXin Long list_del_init(&chk->transmitted_list);
3588dbdf1f5SXin Long sctp_insert_list(&asoc->outqueue.abandoned,
3598dbdf1f5SXin Long &chk->transmitted_list);
3608dbdf1f5SXin Long
36105364ca0SKonstantin Khorenko streamout = SCTP_SO(&asoc->stream, chk->sinfo.sinfo_stream);
3628dbdf1f5SXin Long asoc->sent_cnt_removable--;
3638dbdf1f5SXin Long asoc->abandoned_sent[SCTP_PR_INDEX(PRIO)]++;
364f952be79SMarcelo Ricardo Leitner streamout->ext->abandoned_sent[SCTP_PR_INDEX(PRIO)]++;
3658dbdf1f5SXin Long
366d30fc512SXin Long if (queue != &asoc->outqueue.retransmit &&
367d30fc512SXin Long !chk->tsn_gap_acked) {
3688dbdf1f5SXin Long if (chk->transport)
3698dbdf1f5SXin Long chk->transport->flight_size -=
3708dbdf1f5SXin Long sctp_data_size(chk);
3718dbdf1f5SXin Long asoc->outqueue.outstanding_bytes -= sctp_data_size(chk);
3728dbdf1f5SXin Long }
3738dbdf1f5SXin Long
374605c0ac1SXin Long msg_len -= chk->skb->truesize + sizeof(struct sctp_chunk);
3758dbdf1f5SXin Long if (msg_len <= 0)
3768dbdf1f5SXin Long break;
3778dbdf1f5SXin Long }
3788dbdf1f5SXin Long
3798dbdf1f5SXin Long return msg_len;
3808dbdf1f5SXin Long }
3818dbdf1f5SXin Long
sctp_prsctp_prune_unsent(struct sctp_association * asoc,struct sctp_sndrcvinfo * sinfo,int msg_len)3828dbdf1f5SXin Long static int sctp_prsctp_prune_unsent(struct sctp_association *asoc,
38323bb09cfSXin Long struct sctp_sndrcvinfo *sinfo, int msg_len)
3848dbdf1f5SXin Long {
38523bb09cfSXin Long struct sctp_outq *q = &asoc->outqueue;
3868dbdf1f5SXin Long struct sctp_chunk *chk, *temp;
3879f0b7732SXin Long struct sctp_stream_out *sout;
3888dbdf1f5SXin Long
3895bbbbe32SMarcelo Ricardo Leitner q->sched->unsched_all(&asoc->stream);
3905bbbbe32SMarcelo Ricardo Leitner
39123bb09cfSXin Long list_for_each_entry_safe(chk, temp, &q->out_chunk_list, list) {
392e5f61296SXin Long if (!chk->msg->abandoned &&
393779edd73SXin Long (!(chk->chunk_hdr->flags & SCTP_DATA_FIRST_FRAG) ||
394779edd73SXin Long !SCTP_PR_PRIO_ENABLED(chk->sinfo.sinfo_flags) ||
395e5f61296SXin Long chk->sinfo.sinfo_timetolive <= sinfo->sinfo_timetolive))
3968dbdf1f5SXin Long continue;
3978dbdf1f5SXin Long
398e5f61296SXin Long chk->msg->abandoned = 1;
3995bbbbe32SMarcelo Ricardo Leitner sctp_sched_dequeue_common(q, chk);
4008dbdf1f5SXin Long asoc->sent_cnt_removable--;
4018dbdf1f5SXin Long asoc->abandoned_unsent[SCTP_PR_INDEX(PRIO)]++;
402d229d48dSXin Long
4039f0b7732SXin Long sout = SCTP_SO(&asoc->stream, chk->sinfo.sinfo_stream);
4049f0b7732SXin Long sout->ext->abandoned_unsent[SCTP_PR_INDEX(PRIO)]++;
4058dbdf1f5SXin Long
4062f201ae1SXin Long /* clear out_curr if all frag chunks are pruned */
4072f201ae1SXin Long if (asoc->stream.out_curr == sout &&
4082f201ae1SXin Long list_is_last(&chk->frag_list, &chk->msg->chunks))
4092f201ae1SXin Long asoc->stream.out_curr = NULL;
4102f201ae1SXin Long
411605c0ac1SXin Long msg_len -= chk->skb->truesize + sizeof(struct sctp_chunk);
4128dbdf1f5SXin Long sctp_chunk_free(chk);
4138dbdf1f5SXin Long if (msg_len <= 0)
4148dbdf1f5SXin Long break;
4158dbdf1f5SXin Long }
4168dbdf1f5SXin Long
4175bbbbe32SMarcelo Ricardo Leitner q->sched->sched_all(&asoc->stream);
4185bbbbe32SMarcelo Ricardo Leitner
4198dbdf1f5SXin Long return msg_len;
4208dbdf1f5SXin Long }
4218dbdf1f5SXin Long
4228dbdf1f5SXin Long /* Abandon the chunks according their priorities */
sctp_prsctp_prune(struct sctp_association * asoc,struct sctp_sndrcvinfo * sinfo,int msg_len)4238dbdf1f5SXin Long void sctp_prsctp_prune(struct sctp_association *asoc,
4248dbdf1f5SXin Long struct sctp_sndrcvinfo *sinfo, int msg_len)
4258dbdf1f5SXin Long {
4268dbdf1f5SXin Long struct sctp_transport *transport;
4278dbdf1f5SXin Long
428be4947bfSXin Long if (!asoc->peer.prsctp_capable || !asoc->sent_cnt_removable)
4298dbdf1f5SXin Long return;
4308dbdf1f5SXin Long
4318dbdf1f5SXin Long msg_len = sctp_prsctp_prune_sent(asoc, sinfo,
4328dbdf1f5SXin Long &asoc->outqueue.retransmit,
4338dbdf1f5SXin Long msg_len);
4348dbdf1f5SXin Long if (msg_len <= 0)
4358dbdf1f5SXin Long return;
4368dbdf1f5SXin Long
4378dbdf1f5SXin Long list_for_each_entry(transport, &asoc->peer.transport_addr_list,
4388dbdf1f5SXin Long transports) {
4398dbdf1f5SXin Long msg_len = sctp_prsctp_prune_sent(asoc, sinfo,
4408dbdf1f5SXin Long &transport->transmitted,
4418dbdf1f5SXin Long msg_len);
4428dbdf1f5SXin Long if (msg_len <= 0)
4438dbdf1f5SXin Long return;
4448dbdf1f5SXin Long }
4458dbdf1f5SXin Long
44623bb09cfSXin Long sctp_prsctp_prune_unsent(asoc, sinfo, msg_len);
4478dbdf1f5SXin Long }
4488dbdf1f5SXin Long
4491da177e4SLinus Torvalds /* Mark all the eligible packets on a transport for retransmission. */
sctp_retransmit_mark(struct sctp_outq * q,struct sctp_transport * transport,__u8 reason)4501da177e4SLinus Torvalds void sctp_retransmit_mark(struct sctp_outq *q,
4511da177e4SLinus Torvalds struct sctp_transport *transport,
452b6157d8eSVlad Yasevich __u8 reason)
4531da177e4SLinus Torvalds {
4541da177e4SLinus Torvalds struct list_head *lchunk, *ltemp;
4551da177e4SLinus Torvalds struct sctp_chunk *chunk;
4561da177e4SLinus Torvalds
4571da177e4SLinus Torvalds /* Walk through the specified transmitted queue. */
4581da177e4SLinus Torvalds list_for_each_safe(lchunk, ltemp, &transport->transmitted) {
4591da177e4SLinus Torvalds chunk = list_entry(lchunk, struct sctp_chunk,
4601da177e4SLinus Torvalds transmitted_list);
4611da177e4SLinus Torvalds
4621da177e4SLinus Torvalds /* If the chunk is abandoned, move it to abandoned list. */
4631da177e4SLinus Torvalds if (sctp_chunk_abandoned(chunk)) {
4641da177e4SLinus Torvalds list_del_init(lchunk);
4651da177e4SLinus Torvalds sctp_insert_list(&q->abandoned, lchunk);
4668c4a2d41SVlad Yasevich
4678c4a2d41SVlad Yasevich /* If this chunk has not been previousely acked,
4688c4a2d41SVlad Yasevich * stop considering it 'outstanding'. Our peer
4698c4a2d41SVlad Yasevich * will most likely never see it since it will
4708c4a2d41SVlad Yasevich * not be retransmitted
4718c4a2d41SVlad Yasevich */
4728c4a2d41SVlad Yasevich if (!chunk->tsn_gap_acked) {
47331b02e15SVlad Yasevich if (chunk->transport)
4748c4a2d41SVlad Yasevich chunk->transport->flight_size -=
4758c4a2d41SVlad Yasevich sctp_data_size(chunk);
4768c4a2d41SVlad Yasevich q->outstanding_bytes -= sctp_data_size(chunk);
477a76c0adfSThomas Graf q->asoc->peer.rwnd += sctp_data_size(chunk);
4788c4a2d41SVlad Yasevich }
4791da177e4SLinus Torvalds continue;
4801da177e4SLinus Torvalds }
4811da177e4SLinus Torvalds
482b6157d8eSVlad Yasevich /* If we are doing retransmission due to a timeout or pmtu
483b6157d8eSVlad Yasevich * discovery, only the chunks that are not yet acked should
484b6157d8eSVlad Yasevich * be added to the retransmit queue.
4851da177e4SLinus Torvalds */
486b6157d8eSVlad Yasevich if ((reason == SCTP_RTXR_FAST_RTX &&
487c226ef9bSNeil Horman (chunk->fast_retransmit == SCTP_NEED_FRTX)) ||
488b6157d8eSVlad Yasevich (reason != SCTP_RTXR_FAST_RTX && !chunk->tsn_gap_acked)) {
4891da177e4SLinus Torvalds /* RFC 2960 6.2.1 Processing a Received SACK
4901da177e4SLinus Torvalds *
4911da177e4SLinus Torvalds * C) Any time a DATA chunk is marked for
4921da177e4SLinus Torvalds * retransmission (via either T3-rtx timer expiration
4931da177e4SLinus Torvalds * (Section 6.3.3) or via fast retransmit
4941da177e4SLinus Torvalds * (Section 7.2.4)), add the data size of those
4951da177e4SLinus Torvalds * chunks to the rwnd.
4961da177e4SLinus Torvalds */
497a76c0adfSThomas Graf q->asoc->peer.rwnd += sctp_data_size(chunk);
4981da177e4SLinus Torvalds q->outstanding_bytes -= sctp_data_size(chunk);
49931b02e15SVlad Yasevich if (chunk->transport)
5001da177e4SLinus Torvalds transport->flight_size -= sctp_data_size(chunk);
5011da177e4SLinus Torvalds
5021da177e4SLinus Torvalds /* sctpimpguide-05 Section 2.8.2
5031da177e4SLinus Torvalds * M5) If a T3-rtx timer expires, the
5041da177e4SLinus Torvalds * 'TSN.Missing.Report' of all affected TSNs is set
5051da177e4SLinus Torvalds * to 0.
5061da177e4SLinus Torvalds */
5071da177e4SLinus Torvalds chunk->tsn_missing_report = 0;
5081da177e4SLinus Torvalds
5091da177e4SLinus Torvalds /* If a chunk that is being used for RTT measurement
5101da177e4SLinus Torvalds * has to be retransmitted, we cannot use this chunk
5111da177e4SLinus Torvalds * anymore for RTT measurements. Reset rto_pending so
5121da177e4SLinus Torvalds * that a new RTT measurement is started when a new
5131da177e4SLinus Torvalds * data chunk is sent.
5141da177e4SLinus Torvalds */
5151da177e4SLinus Torvalds if (chunk->rtt_in_progress) {
5161da177e4SLinus Torvalds chunk->rtt_in_progress = 0;
5171da177e4SLinus Torvalds transport->rto_pending = 0;
5181da177e4SLinus Torvalds }
5191da177e4SLinus Torvalds
5201da177e4SLinus Torvalds /* Move the chunk to the retransmit queue. The chunks
5211da177e4SLinus Torvalds * on the retransmit queue are always kept in order.
5221da177e4SLinus Torvalds */
5231da177e4SLinus Torvalds list_del_init(lchunk);
5241da177e4SLinus Torvalds sctp_insert_list(&q->retransmit, lchunk);
5251da177e4SLinus Torvalds }
5261da177e4SLinus Torvalds }
5271da177e4SLinus Torvalds
528bb33381dSDaniel Borkmann pr_debug("%s: transport:%p, reason:%d, cwnd:%d, ssthresh:%d, "
529bb33381dSDaniel Borkmann "flight_size:%d, pba:%d\n", __func__, transport, reason,
530bb33381dSDaniel Borkmann transport->cwnd, transport->ssthresh, transport->flight_size,
5311da177e4SLinus Torvalds transport->partial_bytes_acked);
5321da177e4SLinus Torvalds }
5331da177e4SLinus Torvalds
5341da177e4SLinus Torvalds /* Mark all the eligible packets on a transport for retransmission and force
5351da177e4SLinus Torvalds * one packet out.
5361da177e4SLinus Torvalds */
sctp_retransmit(struct sctp_outq * q,struct sctp_transport * transport,enum sctp_retransmit_reason reason)5371da177e4SLinus Torvalds void sctp_retransmit(struct sctp_outq *q, struct sctp_transport *transport,
538125c2982SXin Long enum sctp_retransmit_reason reason)
5391da177e4SLinus Torvalds {
5404e7696d9SXin Long struct net *net = q->asoc->base.net;
5411da177e4SLinus Torvalds
5421da177e4SLinus Torvalds switch (reason) {
5431da177e4SLinus Torvalds case SCTP_RTXR_T3_RTX:
544b01a2407SEric W. Biederman SCTP_INC_STATS(net, SCTP_MIB_T3_RETRANSMITS);
5451da177e4SLinus Torvalds sctp_transport_lower_cwnd(transport, SCTP_LOWER_CWND_T3_RTX);
5461da177e4SLinus Torvalds /* Update the retran path if the T3-rtx timer has expired for
5471da177e4SLinus Torvalds * the current retran path.
5481da177e4SLinus Torvalds */
5491da177e4SLinus Torvalds if (transport == transport->asoc->peer.retran_path)
5501da177e4SLinus Torvalds sctp_assoc_update_retran_path(transport->asoc);
55158fbbed4SNeil Horman transport->asoc->rtx_data_chunks +=
55258fbbed4SNeil Horman transport->asoc->unack_data;
55370331909SXin Long if (transport->pl.state == SCTP_PL_COMPLETE &&
55470331909SXin Long transport->asoc->unack_data)
55570331909SXin Long sctp_transport_reset_probe_timer(transport);
5561da177e4SLinus Torvalds break;
5571da177e4SLinus Torvalds case SCTP_RTXR_FAST_RTX:
558b01a2407SEric W. Biederman SCTP_INC_STATS(net, SCTP_MIB_FAST_RETRANSMITS);
5591da177e4SLinus Torvalds sctp_transport_lower_cwnd(transport, SCTP_LOWER_CWND_FAST_RTX);
56062aeaff5SVlad Yasevich q->fast_rtx = 1;
5611da177e4SLinus Torvalds break;
5621da177e4SLinus Torvalds case SCTP_RTXR_PMTUD:
563b01a2407SEric W. Biederman SCTP_INC_STATS(net, SCTP_MIB_PMTUD_RETRANSMITS);
5641da177e4SLinus Torvalds break;
565b6157d8eSVlad Yasevich case SCTP_RTXR_T1_RTX:
566b01a2407SEric W. Biederman SCTP_INC_STATS(net, SCTP_MIB_T1_RETRANSMITS);
56758fbbed4SNeil Horman transport->asoc->init_retries++;
568b6157d8eSVlad Yasevich break;
569ac0b0462SSridhar Samudrala default:
570ac0b0462SSridhar Samudrala BUG();
5711da177e4SLinus Torvalds }
5721da177e4SLinus Torvalds
573b6157d8eSVlad Yasevich sctp_retransmit_mark(q, transport, reason);
5741da177e4SLinus Torvalds
5751da177e4SLinus Torvalds /* PR-SCTP A5) Any time the T3-rtx timer expires, on any destination,
5761da177e4SLinus Torvalds * the sender SHOULD try to advance the "Advanced.Peer.Ack.Point" by
5771da177e4SLinus Torvalds * following the procedures outlined in C1 - C5.
5781da177e4SLinus Torvalds */
5798b750ce5SVlad Yasevich if (reason == SCTP_RTXR_T3_RTX)
5808e0c3b73SXin Long q->asoc->stream.si->generate_ftsn(q, q->asoc->ctsn_ack_point);
5811da177e4SLinus Torvalds
5828b750ce5SVlad Yasevich /* Flush the queues only on timeout, since fast_rtx is only
5838b750ce5SVlad Yasevich * triggered during sack processing and the queue
5848b750ce5SVlad Yasevich * will be flushed at the end.
5858b750ce5SVlad Yasevich */
5868b750ce5SVlad Yasevich if (reason != SCTP_RTXR_FAST_RTX)
58764519440SXin Long sctp_outq_flush(q, /* rtx_timeout */ 1, GFP_ATOMIC);
5881da177e4SLinus Torvalds }
5891da177e4SLinus Torvalds
5901da177e4SLinus Torvalds /*
5911da177e4SLinus Torvalds * Transmit DATA chunks on the retransmit queue. Upon return from
59296e0418eSMarcelo Ricardo Leitner * __sctp_outq_flush_rtx() the packet 'pkt' may contain chunks which
5931da177e4SLinus Torvalds * need to be transmitted by the caller.
5941da177e4SLinus Torvalds * We assume that pkt->transport has already been set.
5951da177e4SLinus Torvalds *
5961da177e4SLinus Torvalds * The return value is a normal kernel error return value.
5971da177e4SLinus Torvalds */
__sctp_outq_flush_rtx(struct sctp_outq * q,struct sctp_packet * pkt,int rtx_timeout,int * start_timer,gfp_t gfp)59896e0418eSMarcelo Ricardo Leitner static int __sctp_outq_flush_rtx(struct sctp_outq *q, struct sctp_packet *pkt,
5996605f694SMarcelo Ricardo Leitner int rtx_timeout, int *start_timer, gfp_t gfp)
6001da177e4SLinus Torvalds {
6011da177e4SLinus Torvalds struct sctp_transport *transport = pkt->transport;
6021da177e4SLinus Torvalds struct sctp_chunk *chunk, *chunk1;
60386b36f2aSXin Long struct list_head *lqueue;
60486b36f2aSXin Long enum sctp_xmit status;
6051da177e4SLinus Torvalds int error = 0;
60662aeaff5SVlad Yasevich int timer = 0;
6078b750ce5SVlad Yasevich int done = 0;
60886b36f2aSXin Long int fast_rtx;
6091da177e4SLinus Torvalds
6101da177e4SLinus Torvalds lqueue = &q->retransmit;
61162aeaff5SVlad Yasevich fast_rtx = q->fast_rtx;
6121da177e4SLinus Torvalds
6138b750ce5SVlad Yasevich /* This loop handles time-out retransmissions, fast retransmissions,
6148b750ce5SVlad Yasevich * and retransmissions due to opening of whindow.
6158b750ce5SVlad Yasevich *
6168b750ce5SVlad Yasevich * RFC 2960 6.3.3 Handle T3-rtx Expiration
6171da177e4SLinus Torvalds *
6181da177e4SLinus Torvalds * E3) Determine how many of the earliest (i.e., lowest TSN)
6191da177e4SLinus Torvalds * outstanding DATA chunks for the address for which the
6201da177e4SLinus Torvalds * T3-rtx has expired will fit into a single packet, subject
6211da177e4SLinus Torvalds * to the MTU constraint for the path corresponding to the
6221da177e4SLinus Torvalds * destination transport address to which the retransmission
6231da177e4SLinus Torvalds * is being sent (this may be different from the address for
6241da177e4SLinus Torvalds * which the timer expires [see Section 6.4]). Call this value
6251da177e4SLinus Torvalds * K. Bundle and retransmit those K DATA chunks in a single
6261da177e4SLinus Torvalds * packet to the destination endpoint.
6271da177e4SLinus Torvalds *
6281da177e4SLinus Torvalds * [Just to be painfully clear, if we are retransmitting
6291da177e4SLinus Torvalds * because a timeout just happened, we should send only ONE
6301da177e4SLinus Torvalds * packet of retransmitted data.]
6318b750ce5SVlad Yasevich *
6328b750ce5SVlad Yasevich * For fast retransmissions we also send only ONE packet. However,
6338b750ce5SVlad Yasevich * if we are just flushing the queue due to open window, we'll
6348b750ce5SVlad Yasevich * try to send as much as possible.
6351da177e4SLinus Torvalds */
6368b750ce5SVlad Yasevich list_for_each_entry_safe(chunk, chunk1, lqueue, transmitted_list) {
6374c6a6f42SWei Yongjun /* If the chunk is abandoned, move it to abandoned list. */
6384c6a6f42SWei Yongjun if (sctp_chunk_abandoned(chunk)) {
6394c6a6f42SWei Yongjun list_del_init(&chunk->transmitted_list);
6404c6a6f42SWei Yongjun sctp_insert_list(&q->abandoned,
6414c6a6f42SWei Yongjun &chunk->transmitted_list);
6424c6a6f42SWei Yongjun continue;
6434c6a6f42SWei Yongjun }
6441da177e4SLinus Torvalds
6451da177e4SLinus Torvalds /* Make sure that Gap Acked TSNs are not retransmitted. A
6461da177e4SLinus Torvalds * simple approach is just to move such TSNs out of the
6471da177e4SLinus Torvalds * way and into a 'transmitted' queue and skip to the
6481da177e4SLinus Torvalds * next chunk.
6491da177e4SLinus Torvalds */
6501da177e4SLinus Torvalds if (chunk->tsn_gap_acked) {
65154a27924SWei Yongjun list_move_tail(&chunk->transmitted_list,
6528b750ce5SVlad Yasevich &transport->transmitted);
6531da177e4SLinus Torvalds continue;
6541da177e4SLinus Torvalds }
6551da177e4SLinus Torvalds
6568b750ce5SVlad Yasevich /* If we are doing fast retransmit, ignore non-fast_rtransmit
6578b750ce5SVlad Yasevich * chunks
6588b750ce5SVlad Yasevich */
6598b750ce5SVlad Yasevich if (fast_rtx && !chunk->fast_retransmit)
6608b750ce5SVlad Yasevich continue;
6618b750ce5SVlad Yasevich
662bc4f841aSWei Yongjun redo:
6631da177e4SLinus Torvalds /* Attempt to append this chunk to the packet. */
6641da177e4SLinus Torvalds status = sctp_packet_append_chunk(pkt, chunk);
6651da177e4SLinus Torvalds
6661da177e4SLinus Torvalds switch (status) {
6671da177e4SLinus Torvalds case SCTP_XMIT_PMTU_FULL:
668bc4f841aSWei Yongjun if (!pkt->has_data && !pkt->has_cookie_echo) {
669bc4f841aSWei Yongjun /* If this packet did not contain DATA then
670bc4f841aSWei Yongjun * retransmission did not happen, so do it
671bc4f841aSWei Yongjun * again. We'll ignore the error here since
672bc4f841aSWei Yongjun * control chunks are already freed so there
673bc4f841aSWei Yongjun * is nothing we can do.
674bc4f841aSWei Yongjun */
6756605f694SMarcelo Ricardo Leitner sctp_packet_transmit(pkt, gfp);
676bc4f841aSWei Yongjun goto redo;
677bc4f841aSWei Yongjun }
678bc4f841aSWei Yongjun
6791da177e4SLinus Torvalds /* Send this packet. */
6806605f694SMarcelo Ricardo Leitner error = sctp_packet_transmit(pkt, gfp);
6811da177e4SLinus Torvalds
6821da177e4SLinus Torvalds /* If we are retransmitting, we should only
6831da177e4SLinus Torvalds * send a single packet.
684f246a7b7SVlad Yasevich * Otherwise, try appending this chunk again.
6851da177e4SLinus Torvalds */
6868b750ce5SVlad Yasevich if (rtx_timeout || fast_rtx)
6878b750ce5SVlad Yasevich done = 1;
688f246a7b7SVlad Yasevich else
689f246a7b7SVlad Yasevich goto redo;
6901da177e4SLinus Torvalds
6918b750ce5SVlad Yasevich /* Bundle next chunk in the next round. */
6921da177e4SLinus Torvalds break;
6931da177e4SLinus Torvalds
6941da177e4SLinus Torvalds case SCTP_XMIT_RWND_FULL:
6951da177e4SLinus Torvalds /* Send this packet. */
6966605f694SMarcelo Ricardo Leitner error = sctp_packet_transmit(pkt, gfp);
6971da177e4SLinus Torvalds
6981da177e4SLinus Torvalds /* Stop sending DATA as there is no more room
6991da177e4SLinus Torvalds * at the receiver.
7001da177e4SLinus Torvalds */
7018b750ce5SVlad Yasevich done = 1;
7021da177e4SLinus Torvalds break;
7031da177e4SLinus Torvalds
704526cbef7SDavid Laight case SCTP_XMIT_DELAY:
7051da177e4SLinus Torvalds /* Send this packet. */
7066605f694SMarcelo Ricardo Leitner error = sctp_packet_transmit(pkt, gfp);
7071da177e4SLinus Torvalds
7081da177e4SLinus Torvalds /* Stop sending DATA because of nagle delay. */
7098b750ce5SVlad Yasevich done = 1;
7101da177e4SLinus Torvalds break;
7111da177e4SLinus Torvalds
7121da177e4SLinus Torvalds default:
7131da177e4SLinus Torvalds /* The append was successful, so add this chunk to
7141da177e4SLinus Torvalds * the transmitted list.
7151da177e4SLinus Torvalds */
71654a27924SWei Yongjun list_move_tail(&chunk->transmitted_list,
7178b750ce5SVlad Yasevich &transport->transmitted);
7181da177e4SLinus Torvalds
7191da177e4SLinus Torvalds /* Mark the chunk as ineligible for fast retransmit
7201da177e4SLinus Torvalds * after it is retransmitted.
7211da177e4SLinus Torvalds */
722c226ef9bSNeil Horman if (chunk->fast_retransmit == SCTP_NEED_FRTX)
723c226ef9bSNeil Horman chunk->fast_retransmit = SCTP_DONT_FRTX;
7241da177e4SLinus Torvalds
725196d6759SMichele Baldessari q->asoc->stats.rtxchunks++;
7261da177e4SLinus Torvalds break;
7273ff50b79SStephen Hemminger }
7281da177e4SLinus Torvalds
72962aeaff5SVlad Yasevich /* Set the timer if there were no errors */
73062aeaff5SVlad Yasevich if (!error && !timer)
73162aeaff5SVlad Yasevich timer = 1;
73262aeaff5SVlad Yasevich
7338b750ce5SVlad Yasevich if (done)
7348b750ce5SVlad Yasevich break;
7358b750ce5SVlad Yasevich }
7368b750ce5SVlad Yasevich
7371da177e4SLinus Torvalds /* If we are here due to a retransmit timeout or a fast
7381da177e4SLinus Torvalds * retransmit and if there are any chunks left in the retransmit
73964b0812bSWei Yongjun * queue that could not fit in the PMTU sized packet, they need
74064b0812bSWei Yongjun * to be marked as ineligible for a subsequent fast retransmit.
7411da177e4SLinus Torvalds */
7428b750ce5SVlad Yasevich if (rtx_timeout || fast_rtx) {
7439dbc15f0SRobert P. J. Day list_for_each_entry(chunk1, lqueue, transmitted_list) {
744c226ef9bSNeil Horman if (chunk1->fast_retransmit == SCTP_NEED_FRTX)
745c226ef9bSNeil Horman chunk1->fast_retransmit = SCTP_DONT_FRTX;
7461da177e4SLinus Torvalds }
7471da177e4SLinus Torvalds }
7481da177e4SLinus Torvalds
74962aeaff5SVlad Yasevich *start_timer = timer;
75062aeaff5SVlad Yasevich
75162aeaff5SVlad Yasevich /* Clear fast retransmit hint */
75262aeaff5SVlad Yasevich if (fast_rtx)
75362aeaff5SVlad Yasevich q->fast_rtx = 0;
75462aeaff5SVlad Yasevich
7551da177e4SLinus Torvalds return error;
7561da177e4SLinus Torvalds }
7571da177e4SLinus Torvalds
7581da177e4SLinus Torvalds /* Cork the outqueue so queued chunks are really queued. */
sctp_outq_uncork(struct sctp_outq * q,gfp_t gfp)75983dbc3d4SXin Long void sctp_outq_uncork(struct sctp_outq *q, gfp_t gfp)
7601da177e4SLinus Torvalds {
7617d54dc68SVlad Yasevich if (q->cork)
7621da177e4SLinus Torvalds q->cork = 0;
763dacda32eSDaniel Borkmann
76483dbc3d4SXin Long sctp_outq_flush(q, 0, gfp);
7651da177e4SLinus Torvalds }
7661da177e4SLinus Torvalds
sctp_packet_singleton(struct sctp_transport * transport,struct sctp_chunk * chunk,gfp_t gfp)767b9fd6839SMarcelo Ricardo Leitner static int sctp_packet_singleton(struct sctp_transport *transport,
768b9fd6839SMarcelo Ricardo Leitner struct sctp_chunk *chunk, gfp_t gfp)
769b9fd6839SMarcelo Ricardo Leitner {
770b9fd6839SMarcelo Ricardo Leitner const struct sctp_association *asoc = transport->asoc;
771b9fd6839SMarcelo Ricardo Leitner const __u16 sport = asoc->base.bind_addr.port;
772b9fd6839SMarcelo Ricardo Leitner const __u16 dport = asoc->peer.port;
773b9fd6839SMarcelo Ricardo Leitner const __u32 vtag = asoc->peer.i.init_tag;
774b9fd6839SMarcelo Ricardo Leitner struct sctp_packet singleton;
775b9fd6839SMarcelo Ricardo Leitner
776b9fd6839SMarcelo Ricardo Leitner sctp_packet_init(&singleton, transport, sport, dport);
777b9fd6839SMarcelo Ricardo Leitner sctp_packet_config(&singleton, vtag, 0);
778fe59379bSXin Long if (sctp_packet_append_chunk(&singleton, chunk) != SCTP_XMIT_OK) {
779fe59379bSXin Long list_del_init(&chunk->list);
780fe59379bSXin Long sctp_chunk_free(chunk);
781fe59379bSXin Long return -ENOMEM;
782fe59379bSXin Long }
783b9fd6839SMarcelo Ricardo Leitner return sctp_packet_transmit(&singleton, gfp);
784b9fd6839SMarcelo Ricardo Leitner }
7852e3216cdSVlad Yasevich
786bb543847SMarcelo Ricardo Leitner /* Struct to hold the context during sctp outq flush */
787bb543847SMarcelo Ricardo Leitner struct sctp_flush_ctx {
788bb543847SMarcelo Ricardo Leitner struct sctp_outq *q;
789bb543847SMarcelo Ricardo Leitner /* Current transport being used. It's NOT the same as curr active one */
790bb543847SMarcelo Ricardo Leitner struct sctp_transport *transport;
791bb543847SMarcelo Ricardo Leitner /* These transports have chunks to send. */
792bb543847SMarcelo Ricardo Leitner struct list_head transport_list;
793e136e965SMarcelo Ricardo Leitner struct sctp_association *asoc;
794e136e965SMarcelo Ricardo Leitner /* Packet on the current transport above */
795e136e965SMarcelo Ricardo Leitner struct sctp_packet *packet;
796bb543847SMarcelo Ricardo Leitner gfp_t gfp;
797bb543847SMarcelo Ricardo Leitner };
798bb543847SMarcelo Ricardo Leitner
799bb543847SMarcelo Ricardo Leitner /* transport: current transport */
sctp_outq_select_transport(struct sctp_flush_ctx * ctx,struct sctp_chunk * chunk)800e136e965SMarcelo Ricardo Leitner static void sctp_outq_select_transport(struct sctp_flush_ctx *ctx,
801bb543847SMarcelo Ricardo Leitner struct sctp_chunk *chunk)
8020d634b0cSMarcelo Ricardo Leitner {
8030d634b0cSMarcelo Ricardo Leitner struct sctp_transport *new_transport = chunk->transport;
8040d634b0cSMarcelo Ricardo Leitner
8050d634b0cSMarcelo Ricardo Leitner if (!new_transport) {
8060d634b0cSMarcelo Ricardo Leitner if (!sctp_chunk_is_data(chunk)) {
8075884f35fSMarcelo Ricardo Leitner /* If we have a prior transport pointer, see if
8080d634b0cSMarcelo Ricardo Leitner * the destination address of the chunk
8090d634b0cSMarcelo Ricardo Leitner * matches the destination address of the
8100d634b0cSMarcelo Ricardo Leitner * current transport. If not a match, then
8110d634b0cSMarcelo Ricardo Leitner * try to look up the transport with a given
8120d634b0cSMarcelo Ricardo Leitner * destination address. We do this because
8130d634b0cSMarcelo Ricardo Leitner * after processing ASCONFs, we may have new
8140d634b0cSMarcelo Ricardo Leitner * transports created.
8150d634b0cSMarcelo Ricardo Leitner */
816bb543847SMarcelo Ricardo Leitner if (ctx->transport && sctp_cmp_addr_exact(&chunk->dest,
817bb543847SMarcelo Ricardo Leitner &ctx->transport->ipaddr))
818bb543847SMarcelo Ricardo Leitner new_transport = ctx->transport;
8190d634b0cSMarcelo Ricardo Leitner else
820e136e965SMarcelo Ricardo Leitner new_transport = sctp_assoc_lookup_paddr(ctx->asoc,
8210d634b0cSMarcelo Ricardo Leitner &chunk->dest);
8220d634b0cSMarcelo Ricardo Leitner }
8230d634b0cSMarcelo Ricardo Leitner
8240d634b0cSMarcelo Ricardo Leitner /* if we still don't have a new transport, then
8250d634b0cSMarcelo Ricardo Leitner * use the current active path.
8260d634b0cSMarcelo Ricardo Leitner */
8270d634b0cSMarcelo Ricardo Leitner if (!new_transport)
828e136e965SMarcelo Ricardo Leitner new_transport = ctx->asoc->peer.active_path;
8290d634b0cSMarcelo Ricardo Leitner } else {
8300d634b0cSMarcelo Ricardo Leitner __u8 type;
8310d634b0cSMarcelo Ricardo Leitner
8320d634b0cSMarcelo Ricardo Leitner switch (new_transport->state) {
8330d634b0cSMarcelo Ricardo Leitner case SCTP_INACTIVE:
8340d634b0cSMarcelo Ricardo Leitner case SCTP_UNCONFIRMED:
8350d634b0cSMarcelo Ricardo Leitner case SCTP_PF:
8360d634b0cSMarcelo Ricardo Leitner /* If the chunk is Heartbeat or Heartbeat Ack,
8370d634b0cSMarcelo Ricardo Leitner * send it to chunk->transport, even if it's
8380d634b0cSMarcelo Ricardo Leitner * inactive.
8390d634b0cSMarcelo Ricardo Leitner *
8400d634b0cSMarcelo Ricardo Leitner * 3.3.6 Heartbeat Acknowledgement:
8410d634b0cSMarcelo Ricardo Leitner * ...
8420d634b0cSMarcelo Ricardo Leitner * A HEARTBEAT ACK is always sent to the source IP
8430d634b0cSMarcelo Ricardo Leitner * address of the IP datagram containing the
8440d634b0cSMarcelo Ricardo Leitner * HEARTBEAT chunk to which this ack is responding.
8450d634b0cSMarcelo Ricardo Leitner * ...
8460d634b0cSMarcelo Ricardo Leitner *
8470d634b0cSMarcelo Ricardo Leitner * ASCONF_ACKs also must be sent to the source.
8480d634b0cSMarcelo Ricardo Leitner */
8490d634b0cSMarcelo Ricardo Leitner type = chunk->chunk_hdr->type;
8500d634b0cSMarcelo Ricardo Leitner if (type != SCTP_CID_HEARTBEAT &&
8510d634b0cSMarcelo Ricardo Leitner type != SCTP_CID_HEARTBEAT_ACK &&
8520d634b0cSMarcelo Ricardo Leitner type != SCTP_CID_ASCONF_ACK)
853e136e965SMarcelo Ricardo Leitner new_transport = ctx->asoc->peer.active_path;
8540d634b0cSMarcelo Ricardo Leitner break;
8550d634b0cSMarcelo Ricardo Leitner default:
8560d634b0cSMarcelo Ricardo Leitner break;
8570d634b0cSMarcelo Ricardo Leitner }
8580d634b0cSMarcelo Ricardo Leitner }
8590d634b0cSMarcelo Ricardo Leitner
8600d634b0cSMarcelo Ricardo Leitner /* Are we switching transports? Take care of transport locks. */
861bb543847SMarcelo Ricardo Leitner if (new_transport != ctx->transport) {
862bb543847SMarcelo Ricardo Leitner ctx->transport = new_transport;
863e136e965SMarcelo Ricardo Leitner ctx->packet = &ctx->transport->packet;
864e136e965SMarcelo Ricardo Leitner
865bb543847SMarcelo Ricardo Leitner if (list_empty(&ctx->transport->send_ready))
866bb543847SMarcelo Ricardo Leitner list_add_tail(&ctx->transport->send_ready,
867bb543847SMarcelo Ricardo Leitner &ctx->transport_list);
8680d634b0cSMarcelo Ricardo Leitner
869e136e965SMarcelo Ricardo Leitner sctp_packet_config(ctx->packet,
870e136e965SMarcelo Ricardo Leitner ctx->asoc->peer.i.init_tag,
871e136e965SMarcelo Ricardo Leitner ctx->asoc->peer.ecn_capable);
8720d634b0cSMarcelo Ricardo Leitner /* We've switched transports, so apply the
8730d634b0cSMarcelo Ricardo Leitner * Burst limit to the new transport.
8740d634b0cSMarcelo Ricardo Leitner */
875bb543847SMarcelo Ricardo Leitner sctp_transport_burst_limited(ctx->transport);
8760d634b0cSMarcelo Ricardo Leitner }
8770d634b0cSMarcelo Ricardo Leitner }
8780d634b0cSMarcelo Ricardo Leitner
sctp_outq_flush_ctrl(struct sctp_flush_ctx * ctx)879bb543847SMarcelo Ricardo Leitner static void sctp_outq_flush_ctrl(struct sctp_flush_ctx *ctx)
8801da177e4SLinus Torvalds {
88179af02c2SDavid S. Miller struct sctp_chunk *chunk, *tmp;
88286b36f2aSXin Long enum sctp_xmit status;
8837a0b9df6SMarcelo Ricardo Leitner int one_packet, error;
8841da177e4SLinus Torvalds
885bb543847SMarcelo Ricardo Leitner list_for_each_entry_safe(chunk, tmp, &ctx->q->control_chunk_list, list) {
8867a0b9df6SMarcelo Ricardo Leitner one_packet = 0;
8877a0b9df6SMarcelo Ricardo Leitner
8888a07eb0aSMichio Honda /* RFC 5061, 5.3
8898a07eb0aSMichio Honda * F1) This means that until such time as the ASCONF
8908a07eb0aSMichio Honda * containing the add is acknowledged, the sender MUST
8918a07eb0aSMichio Honda * NOT use the new IP address as a source for ANY SCTP
8928a07eb0aSMichio Honda * packet except on carrying an ASCONF Chunk.
8938a07eb0aSMichio Honda */
894e136e965SMarcelo Ricardo Leitner if (ctx->asoc->src_out_of_asoc_ok &&
8958a07eb0aSMichio Honda chunk->chunk_hdr->type != SCTP_CID_ASCONF)
8968a07eb0aSMichio Honda continue;
8978a07eb0aSMichio Honda
89879af02c2SDavid S. Miller list_del_init(&chunk->list);
89979af02c2SDavid S. Miller
9000d634b0cSMarcelo Ricardo Leitner /* Pick the right transport to use. Should always be true for
9010d634b0cSMarcelo Ricardo Leitner * the first chunk as we don't have a transport by then.
902a08de64dSVlad Yasevich */
903e136e965SMarcelo Ricardo Leitner sctp_outq_select_transport(ctx, chunk);
9041da177e4SLinus Torvalds
9051da177e4SLinus Torvalds switch (chunk->chunk_hdr->type) {
9065884f35fSMarcelo Ricardo Leitner /* 6.10 Bundling
9071da177e4SLinus Torvalds * ...
9081da177e4SLinus Torvalds * An endpoint MUST NOT bundle INIT, INIT ACK or SHUTDOWN
9091da177e4SLinus Torvalds * COMPLETE with any other chunks. [Send them immediately.]
9101da177e4SLinus Torvalds */
9111da177e4SLinus Torvalds case SCTP_CID_INIT:
9121da177e4SLinus Torvalds case SCTP_CID_INIT_ACK:
9131da177e4SLinus Torvalds case SCTP_CID_SHUTDOWN_COMPLETE:
914bb543847SMarcelo Ricardo Leitner error = sctp_packet_singleton(ctx->transport, chunk,
915bb543847SMarcelo Ricardo Leitner ctx->gfp);
91664519440SXin Long if (error < 0) {
917e136e965SMarcelo Ricardo Leitner ctx->asoc->base.sk->sk_err = -error;
91883dbc3d4SXin Long return;
91964519440SXin Long }
920e3d37210SJamie Bainbridge ctx->asoc->stats.octrlchunks++;
9211da177e4SLinus Torvalds break;
9221da177e4SLinus Torvalds
9231da177e4SLinus Torvalds case SCTP_CID_ABORT:
92437f47bc9SMarcelo Ricardo Leitner if (sctp_test_T_bit(chunk))
925e136e965SMarcelo Ricardo Leitner ctx->packet->vtag = ctx->asoc->c.my_vtag;
926df561f66SGustavo A. R. Silva fallthrough;
9277a0b9df6SMarcelo Ricardo Leitner
9282e3216cdSVlad Yasevich /* The following chunks are "response" chunks, i.e.
9292e3216cdSVlad Yasevich * they are generated in response to something we
9302e3216cdSVlad Yasevich * received. If we are sending these, then we can
9312e3216cdSVlad Yasevich * send only 1 packet containing these chunks.
9322e3216cdSVlad Yasevich */
9332e3216cdSVlad Yasevich case SCTP_CID_HEARTBEAT_ACK:
9342e3216cdSVlad Yasevich case SCTP_CID_SHUTDOWN_ACK:
9352e3216cdSVlad Yasevich case SCTP_CID_COOKIE_ACK:
9362e3216cdSVlad Yasevich case SCTP_CID_COOKIE_ECHO:
9372e3216cdSVlad Yasevich case SCTP_CID_ERROR:
9382e3216cdSVlad Yasevich case SCTP_CID_ECN_CWR:
9392e3216cdSVlad Yasevich case SCTP_CID_ASCONF_ACK:
9402e3216cdSVlad Yasevich one_packet = 1;
941df561f66SGustavo A. R. Silva fallthrough;
9422e3216cdSVlad Yasevich
9431da177e4SLinus Torvalds case SCTP_CID_HEARTBEAT:
944fe59379bSXin Long if (chunk->pmtu_probe) {
945e3d37210SJamie Bainbridge error = sctp_packet_singleton(ctx->transport,
946e3d37210SJamie Bainbridge chunk, ctx->gfp);
947e3d37210SJamie Bainbridge if (!error)
948e3d37210SJamie Bainbridge ctx->asoc->stats.octrlchunks++;
949fe59379bSXin Long break;
950fe59379bSXin Long }
951fe59379bSXin Long fallthrough;
952fe59379bSXin Long case SCTP_CID_SACK:
9531da177e4SLinus Torvalds case SCTP_CID_SHUTDOWN:
9541da177e4SLinus Torvalds case SCTP_CID_ECN_ECNE:
9551da177e4SLinus Torvalds case SCTP_CID_ASCONF:
9561da177e4SLinus Torvalds case SCTP_CID_FWD_TSN:
9578e0c3b73SXin Long case SCTP_CID_I_FWD_TSN:
9587f9d68acSXin Long case SCTP_CID_RECONF:
959e136e965SMarcelo Ricardo Leitner status = sctp_packet_transmit_chunk(ctx->packet, chunk,
960bb543847SMarcelo Ricardo Leitner one_packet, ctx->gfp);
9612e3216cdSVlad Yasevich if (status != SCTP_XMIT_OK) {
9622e3216cdSVlad Yasevich /* put the chunk back */
963bb543847SMarcelo Ricardo Leitner list_add(&chunk->list, &ctx->q->control_chunk_list);
9647f9d68acSXin Long break;
9657f9d68acSXin Long }
9667f9d68acSXin Long
967e136e965SMarcelo Ricardo Leitner ctx->asoc->stats.octrlchunks++;
968bd69b981SWei Yongjun /* PR-SCTP C5) If a FORWARD TSN is sent, the
969bd69b981SWei Yongjun * sender MUST assure that at least one T3-rtx
970bd69b981SWei Yongjun * timer is running.
971bd69b981SWei Yongjun */
9728e0c3b73SXin Long if (chunk->chunk_hdr->type == SCTP_CID_FWD_TSN ||
9738e0c3b73SXin Long chunk->chunk_hdr->type == SCTP_CID_I_FWD_TSN) {
974bb543847SMarcelo Ricardo Leitner sctp_transport_reset_t3_rtx(ctx->transport);
975bb543847SMarcelo Ricardo Leitner ctx->transport->last_time_sent = jiffies;
976ba6f5e33SMarcelo Ricardo Leitner }
9777f9d68acSXin Long
978e136e965SMarcelo Ricardo Leitner if (chunk == ctx->asoc->strreset_chunk)
979bb543847SMarcelo Ricardo Leitner sctp_transport_reset_reconf_timer(ctx->transport);
9807f9d68acSXin Long
9811da177e4SLinus Torvalds break;
9821da177e4SLinus Torvalds
9831da177e4SLinus Torvalds default:
9841da177e4SLinus Torvalds /* We built a chunk with an illegal type! */
9851da177e4SLinus Torvalds BUG();
9863ff50b79SStephen Hemminger }
9871da177e4SLinus Torvalds }
9887a0b9df6SMarcelo Ricardo Leitner }
9897a0b9df6SMarcelo Ricardo Leitner
99096e0418eSMarcelo Ricardo Leitner /* Returns false if new data shouldn't be sent */
sctp_outq_flush_rtx(struct sctp_flush_ctx * ctx,int rtx_timeout)991bb543847SMarcelo Ricardo Leitner static bool sctp_outq_flush_rtx(struct sctp_flush_ctx *ctx,
992bb543847SMarcelo Ricardo Leitner int rtx_timeout)
99396e0418eSMarcelo Ricardo Leitner {
99496e0418eSMarcelo Ricardo Leitner int error, start_timer = 0;
99596e0418eSMarcelo Ricardo Leitner
996e136e965SMarcelo Ricardo Leitner if (ctx->asoc->peer.retran_path->state == SCTP_UNCONFIRMED)
99796e0418eSMarcelo Ricardo Leitner return false;
99896e0418eSMarcelo Ricardo Leitner
999e136e965SMarcelo Ricardo Leitner if (ctx->transport != ctx->asoc->peer.retran_path) {
100096e0418eSMarcelo Ricardo Leitner /* Switch transports & prepare the packet. */
1001e136e965SMarcelo Ricardo Leitner ctx->transport = ctx->asoc->peer.retran_path;
1002e136e965SMarcelo Ricardo Leitner ctx->packet = &ctx->transport->packet;
100396e0418eSMarcelo Ricardo Leitner
1004bb543847SMarcelo Ricardo Leitner if (list_empty(&ctx->transport->send_ready))
1005bb543847SMarcelo Ricardo Leitner list_add_tail(&ctx->transport->send_ready,
1006bb543847SMarcelo Ricardo Leitner &ctx->transport_list);
100796e0418eSMarcelo Ricardo Leitner
1008e136e965SMarcelo Ricardo Leitner sctp_packet_config(ctx->packet, ctx->asoc->peer.i.init_tag,
1009e136e965SMarcelo Ricardo Leitner ctx->asoc->peer.ecn_capable);
101096e0418eSMarcelo Ricardo Leitner }
101196e0418eSMarcelo Ricardo Leitner
1012e136e965SMarcelo Ricardo Leitner error = __sctp_outq_flush_rtx(ctx->q, ctx->packet, rtx_timeout,
1013e136e965SMarcelo Ricardo Leitner &start_timer, ctx->gfp);
101496e0418eSMarcelo Ricardo Leitner if (error < 0)
1015e136e965SMarcelo Ricardo Leitner ctx->asoc->base.sk->sk_err = -error;
101696e0418eSMarcelo Ricardo Leitner
101796e0418eSMarcelo Ricardo Leitner if (start_timer) {
1018bb543847SMarcelo Ricardo Leitner sctp_transport_reset_t3_rtx(ctx->transport);
1019bb543847SMarcelo Ricardo Leitner ctx->transport->last_time_sent = jiffies;
102096e0418eSMarcelo Ricardo Leitner }
102196e0418eSMarcelo Ricardo Leitner
102296e0418eSMarcelo Ricardo Leitner /* This can happen on COOKIE-ECHO resend. Only
102396e0418eSMarcelo Ricardo Leitner * one chunk can get bundled with a COOKIE-ECHO.
102496e0418eSMarcelo Ricardo Leitner */
1025e136e965SMarcelo Ricardo Leitner if (ctx->packet->has_cookie_echo)
102696e0418eSMarcelo Ricardo Leitner return false;
102796e0418eSMarcelo Ricardo Leitner
102896e0418eSMarcelo Ricardo Leitner /* Don't send new data if there is still data
102996e0418eSMarcelo Ricardo Leitner * waiting to retransmit.
103096e0418eSMarcelo Ricardo Leitner */
1031bb543847SMarcelo Ricardo Leitner if (!list_empty(&ctx->q->retransmit))
103296e0418eSMarcelo Ricardo Leitner return false;
103396e0418eSMarcelo Ricardo Leitner
103496e0418eSMarcelo Ricardo Leitner return true;
103596e0418eSMarcelo Ricardo Leitner }
1036cb93cc5dSMarcelo Ricardo Leitner
sctp_outq_flush_data(struct sctp_flush_ctx * ctx,int rtx_timeout)1037bb543847SMarcelo Ricardo Leitner static void sctp_outq_flush_data(struct sctp_flush_ctx *ctx,
1038bb543847SMarcelo Ricardo Leitner int rtx_timeout)
10397a0b9df6SMarcelo Ricardo Leitner {
10407a0b9df6SMarcelo Ricardo Leitner struct sctp_chunk *chunk;
10417a0b9df6SMarcelo Ricardo Leitner enum sctp_xmit status;
10428a07eb0aSMichio Honda
10431da177e4SLinus Torvalds /* Is it OK to send data chunks? */
1044e136e965SMarcelo Ricardo Leitner switch (ctx->asoc->state) {
10451da177e4SLinus Torvalds case SCTP_STATE_COOKIE_ECHOED:
10461da177e4SLinus Torvalds /* Only allow bundling when this packet has a COOKIE-ECHO
10471da177e4SLinus Torvalds * chunk.
10481da177e4SLinus Torvalds */
1049e136e965SMarcelo Ricardo Leitner if (!ctx->packet || !ctx->packet->has_cookie_echo)
10504fdbb0efSMarcelo Ricardo Leitner return;
10511da177e4SLinus Torvalds
1052df561f66SGustavo A. R. Silva fallthrough;
10531da177e4SLinus Torvalds case SCTP_STATE_ESTABLISHED:
10541da177e4SLinus Torvalds case SCTP_STATE_SHUTDOWN_PENDING:
10551da177e4SLinus Torvalds case SCTP_STATE_SHUTDOWN_RECEIVED:
10564fdbb0efSMarcelo Ricardo Leitner break;
10574fdbb0efSMarcelo Ricardo Leitner
10584fdbb0efSMarcelo Ricardo Leitner default:
10594fdbb0efSMarcelo Ricardo Leitner /* Do nothing. */
10604fdbb0efSMarcelo Ricardo Leitner return;
10614fdbb0efSMarcelo Ricardo Leitner }
10624fdbb0efSMarcelo Ricardo Leitner
10635884f35fSMarcelo Ricardo Leitner /* RFC 2960 6.1 Transmission of DATA Chunks
10641da177e4SLinus Torvalds *
10651da177e4SLinus Torvalds * C) When the time comes for the sender to transmit,
10661da177e4SLinus Torvalds * before sending new DATA chunks, the sender MUST
10671da177e4SLinus Torvalds * first transmit any outstanding DATA chunks which
10681da177e4SLinus Torvalds * are marked for retransmission (limited by the
10691da177e4SLinus Torvalds * current cwnd).
10701da177e4SLinus Torvalds */
1071e136e965SMarcelo Ricardo Leitner if (!list_empty(&ctx->q->retransmit) &&
1072e136e965SMarcelo Ricardo Leitner !sctp_outq_flush_rtx(ctx, rtx_timeout))
10734fdbb0efSMarcelo Ricardo Leitner return;
10741da177e4SLinus Torvalds
107546d5a808SVlad Yasevich /* Apply Max.Burst limitation to the current transport in
107646d5a808SVlad Yasevich * case it will be used for new data. We are going to
107746d5a808SVlad Yasevich * rest it before we return, but we want to apply the limit
107846d5a808SVlad Yasevich * to the currently queued data.
107946d5a808SVlad Yasevich */
1080bb543847SMarcelo Ricardo Leitner if (ctx->transport)
1081bb543847SMarcelo Ricardo Leitner sctp_transport_burst_limited(ctx->transport);
108246d5a808SVlad Yasevich
10831da177e4SLinus Torvalds /* Finally, transmit new packets. */
1084bb543847SMarcelo Ricardo Leitner while ((chunk = sctp_outq_dequeue_data(ctx->q)) != NULL) {
10857f9d68acSXin Long __u32 sid = ntohs(chunk->subh.data_hdr->stream);
108605364ca0SKonstantin Khorenko __u8 stream_state = SCTP_SO(&ctx->asoc->stream, sid)->state;
10877f9d68acSXin Long
10881da177e4SLinus Torvalds /* Has this chunk expired? */
10891da177e4SLinus Torvalds if (sctp_chunk_abandoned(chunk)) {
1090bb543847SMarcelo Ricardo Leitner sctp_sched_dequeue_done(ctx->q, chunk);
10911da177e4SLinus Torvalds sctp_chunk_fail(chunk, 0);
10921da177e4SLinus Torvalds sctp_chunk_free(chunk);
10931da177e4SLinus Torvalds continue;
10941da177e4SLinus Torvalds }
10951da177e4SLinus Torvalds
109605364ca0SKonstantin Khorenko if (stream_state == SCTP_STREAM_CLOSED) {
1097bb543847SMarcelo Ricardo Leitner sctp_outq_head_data(ctx->q, chunk);
1098cb93cc5dSMarcelo Ricardo Leitner break;
10997f9d68acSXin Long }
11007f9d68acSXin Long
1101e136e965SMarcelo Ricardo Leitner sctp_outq_select_transport(ctx, chunk);
11021da177e4SLinus Torvalds
11035884f35fSMarcelo Ricardo Leitner pr_debug("%s: outq:%p, chunk:%p[%s], tx-tsn:0x%x skb->head:%p skb->users:%d\n",
1104bb543847SMarcelo Ricardo Leitner __func__, ctx->q, chunk, chunk && chunk->chunk_hdr ?
1105bb33381dSDaniel Borkmann sctp_cname(SCTP_ST_CHUNK(chunk->chunk_hdr->type)) :
1106bb33381dSDaniel Borkmann "illegal chunk", ntohl(chunk->subh.data_hdr->tsn),
1107bb33381dSDaniel Borkmann chunk->skb ? chunk->skb->head : NULL, chunk->skb ?
110863354797SReshetova, Elena refcount_read(&chunk->skb->users) : -1);
11091da177e4SLinus Torvalds
11101da177e4SLinus Torvalds /* Add the chunk to the packet. */
1111e136e965SMarcelo Ricardo Leitner status = sctp_packet_transmit_chunk(ctx->packet, chunk, 0,
1112e136e965SMarcelo Ricardo Leitner ctx->gfp);
11134fdbb0efSMarcelo Ricardo Leitner if (status != SCTP_XMIT_OK) {
11141da177e4SLinus Torvalds /* We could not append this chunk, so put
11151da177e4SLinus Torvalds * the chunk back on the output queue.
11161da177e4SLinus Torvalds */
1117bb33381dSDaniel Borkmann pr_debug("%s: could not transmit tsn:0x%x, status:%d\n",
1118bb33381dSDaniel Borkmann __func__, ntohl(chunk->subh.data_hdr->tsn),
11191da177e4SLinus Torvalds status);
1120bb33381dSDaniel Borkmann
1121bb543847SMarcelo Ricardo Leitner sctp_outq_head_data(ctx->q, chunk);
11224fdbb0efSMarcelo Ricardo Leitner break;
1123cb93cc5dSMarcelo Ricardo Leitner }
11241da177e4SLinus Torvalds
1125b93d6471SWei Yongjun /* The sender is in the SHUTDOWN-PENDING state,
1126b93d6471SWei Yongjun * The sender MAY set the I-bit in the DATA
1127b93d6471SWei Yongjun * chunk header.
1128b93d6471SWei Yongjun */
1129e136e965SMarcelo Ricardo Leitner if (ctx->asoc->state == SCTP_STATE_SHUTDOWN_PENDING)
1130b93d6471SWei Yongjun chunk->chunk_hdr->flags |= SCTP_DATA_SACK_IMM;
1131196d6759SMichele Baldessari if (chunk->chunk_hdr->flags & SCTP_DATA_UNORDERED)
1132e136e965SMarcelo Ricardo Leitner ctx->asoc->stats.ouodchunks++;
1133196d6759SMichele Baldessari else
1134e136e965SMarcelo Ricardo Leitner ctx->asoc->stats.oodchunks++;
1135b93d6471SWei Yongjun
11365bbbbe32SMarcelo Ricardo Leitner /* Only now it's safe to consider this
11375bbbbe32SMarcelo Ricardo Leitner * chunk as sent, sched-wise.
11385bbbbe32SMarcelo Ricardo Leitner */
1139bb543847SMarcelo Ricardo Leitner sctp_sched_dequeue_done(ctx->q, chunk);
11405bbbbe32SMarcelo Ricardo Leitner
11411da177e4SLinus Torvalds list_add_tail(&chunk->transmitted_list,
1142bb543847SMarcelo Ricardo Leitner &ctx->transport->transmitted);
11431da177e4SLinus Torvalds
1144bb543847SMarcelo Ricardo Leitner sctp_transport_reset_t3_rtx(ctx->transport);
1145bb543847SMarcelo Ricardo Leitner ctx->transport->last_time_sent = jiffies;
11461da177e4SLinus Torvalds
11471da177e4SLinus Torvalds /* Only let one DATA chunk get bundled with a
11481da177e4SLinus Torvalds * COOKIE-ECHO chunk.
11491da177e4SLinus Torvalds */
1150e136e965SMarcelo Ricardo Leitner if (ctx->packet->has_cookie_echo)
1151cb93cc5dSMarcelo Ricardo Leitner break;
11521da177e4SLinus Torvalds }
1153cb93cc5dSMarcelo Ricardo Leitner }
1154cb93cc5dSMarcelo Ricardo Leitner
sctp_outq_flush_transports(struct sctp_flush_ctx * ctx)1155bb543847SMarcelo Ricardo Leitner static void sctp_outq_flush_transports(struct sctp_flush_ctx *ctx)
11564bf21b61SMarcelo Ricardo Leitner {
11578ff0b1f0SXin Long struct sock *sk = ctx->asoc->base.sk;
11584bf21b61SMarcelo Ricardo Leitner struct list_head *ltransport;
11594bf21b61SMarcelo Ricardo Leitner struct sctp_packet *packet;
11604bf21b61SMarcelo Ricardo Leitner struct sctp_transport *t;
11614bf21b61SMarcelo Ricardo Leitner int error = 0;
11624bf21b61SMarcelo Ricardo Leitner
1163bb543847SMarcelo Ricardo Leitner while ((ltransport = sctp_list_dequeue(&ctx->transport_list)) != NULL) {
11644bf21b61SMarcelo Ricardo Leitner t = list_entry(ltransport, struct sctp_transport, send_ready);
11654bf21b61SMarcelo Ricardo Leitner packet = &t->packet;
11664bf21b61SMarcelo Ricardo Leitner if (!sctp_packet_empty(packet)) {
11678ff0b1f0SXin Long rcu_read_lock();
11688ff0b1f0SXin Long if (t->dst && __sk_dst_get(sk) != t->dst) {
11698ff0b1f0SXin Long dst_hold(t->dst);
11708ff0b1f0SXin Long sk_setup_caps(sk, t->dst);
11718ff0b1f0SXin Long }
11728ff0b1f0SXin Long rcu_read_unlock();
1173bb543847SMarcelo Ricardo Leitner error = sctp_packet_transmit(packet, ctx->gfp);
11744bf21b61SMarcelo Ricardo Leitner if (error < 0)
1175bb543847SMarcelo Ricardo Leitner ctx->q->asoc->base.sk->sk_err = -error;
11764bf21b61SMarcelo Ricardo Leitner }
11774bf21b61SMarcelo Ricardo Leitner
11784bf21b61SMarcelo Ricardo Leitner /* Clear the burst limited state, if any */
11794bf21b61SMarcelo Ricardo Leitner sctp_transport_burst_reset(t);
11804bf21b61SMarcelo Ricardo Leitner }
11814bf21b61SMarcelo Ricardo Leitner }
11824bf21b61SMarcelo Ricardo Leitner
11835884f35fSMarcelo Ricardo Leitner /* Try to flush an outqueue.
1184cb93cc5dSMarcelo Ricardo Leitner *
1185cb93cc5dSMarcelo Ricardo Leitner * Description: Send everything in q which we legally can, subject to
1186cb93cc5dSMarcelo Ricardo Leitner * congestion limitations.
1187cb93cc5dSMarcelo Ricardo Leitner * * Note: This function can be called from multiple contexts so appropriate
1188cb93cc5dSMarcelo Ricardo Leitner * locking concerns must be made. Today we use the sock lock to protect
1189cb93cc5dSMarcelo Ricardo Leitner * this function.
1190cb93cc5dSMarcelo Ricardo Leitner */
1191bb543847SMarcelo Ricardo Leitner
sctp_outq_flush(struct sctp_outq * q,int rtx_timeout,gfp_t gfp)1192cb93cc5dSMarcelo Ricardo Leitner static void sctp_outq_flush(struct sctp_outq *q, int rtx_timeout, gfp_t gfp)
1193cb93cc5dSMarcelo Ricardo Leitner {
1194bb543847SMarcelo Ricardo Leitner struct sctp_flush_ctx ctx = {
1195bb543847SMarcelo Ricardo Leitner .q = q,
1196bb543847SMarcelo Ricardo Leitner .transport = NULL,
1197bb543847SMarcelo Ricardo Leitner .transport_list = LIST_HEAD_INIT(ctx.transport_list),
1198e136e965SMarcelo Ricardo Leitner .asoc = q->asoc,
1199e136e965SMarcelo Ricardo Leitner .packet = NULL,
1200bb543847SMarcelo Ricardo Leitner .gfp = gfp,
1201bb543847SMarcelo Ricardo Leitner };
1202cb93cc5dSMarcelo Ricardo Leitner
12035884f35fSMarcelo Ricardo Leitner /* 6.10 Bundling
1204cb93cc5dSMarcelo Ricardo Leitner * ...
1205cb93cc5dSMarcelo Ricardo Leitner * When bundling control chunks with DATA chunks, an
1206cb93cc5dSMarcelo Ricardo Leitner * endpoint MUST place control chunks first in the outbound
1207cb93cc5dSMarcelo Ricardo Leitner * SCTP packet. The transmitter MUST transmit DATA chunks
1208cb93cc5dSMarcelo Ricardo Leitner * within a SCTP packet in increasing order of TSN.
1209cb93cc5dSMarcelo Ricardo Leitner * ...
1210cb93cc5dSMarcelo Ricardo Leitner */
1211cb93cc5dSMarcelo Ricardo Leitner
1212bb543847SMarcelo Ricardo Leitner sctp_outq_flush_ctrl(&ctx);
1213cb93cc5dSMarcelo Ricardo Leitner
1214cb93cc5dSMarcelo Ricardo Leitner if (q->asoc->src_out_of_asoc_ok)
1215cb93cc5dSMarcelo Ricardo Leitner goto sctp_flush_out;
1216cb93cc5dSMarcelo Ricardo Leitner
1217bb543847SMarcelo Ricardo Leitner sctp_outq_flush_data(&ctx, rtx_timeout);
12181da177e4SLinus Torvalds
12191da177e4SLinus Torvalds sctp_flush_out:
12201da177e4SLinus Torvalds
1221bb543847SMarcelo Ricardo Leitner sctp_outq_flush_transports(&ctx);
12221da177e4SLinus Torvalds }
12231da177e4SLinus Torvalds
12241da177e4SLinus Torvalds /* Update unack_data based on the incoming SACK chunk */
sctp_sack_update_unack_data(struct sctp_association * assoc,struct sctp_sackhdr * sack)12251da177e4SLinus Torvalds static void sctp_sack_update_unack_data(struct sctp_association *assoc,
12261da177e4SLinus Torvalds struct sctp_sackhdr *sack)
12271da177e4SLinus Torvalds {
1228afd93b7bSXin Long union sctp_sack_variable *frags;
12291da177e4SLinus Torvalds __u16 unack_data;
12301da177e4SLinus Torvalds int i;
12311da177e4SLinus Torvalds
12321da177e4SLinus Torvalds unack_data = assoc->next_tsn - assoc->ctsn_ack_point - 1;
12331da177e4SLinus Torvalds
1234*9789c1c6SXin Long frags = (union sctp_sack_variable *)(sack + 1);
12351da177e4SLinus Torvalds for (i = 0; i < ntohs(sack->num_gap_ack_blocks); i++) {
12361da177e4SLinus Torvalds unack_data -= ((ntohs(frags[i].gab.end) -
12371da177e4SLinus Torvalds ntohs(frags[i].gab.start) + 1));
12381da177e4SLinus Torvalds }
12391da177e4SLinus Torvalds
12401da177e4SLinus Torvalds assoc->unack_data = unack_data;
12411da177e4SLinus Torvalds }
12421da177e4SLinus Torvalds
12431da177e4SLinus Torvalds /* This is where we REALLY process a SACK.
12441da177e4SLinus Torvalds *
12451da177e4SLinus Torvalds * Process the SACK against the outqueue. Mostly, this just frees
12461da177e4SLinus Torvalds * things off the transmitted queue.
12471da177e4SLinus Torvalds */
sctp_outq_sack(struct sctp_outq * q,struct sctp_chunk * chunk)1248edfee033SNicolas Dichtel int sctp_outq_sack(struct sctp_outq *q, struct sctp_chunk *chunk)
12491da177e4SLinus Torvalds {
12501da177e4SLinus Torvalds struct sctp_association *asoc = q->asoc;
1251edfee033SNicolas Dichtel struct sctp_sackhdr *sack = chunk->subh.sack_hdr;
12521da177e4SLinus Torvalds struct sctp_transport *transport;
12531da177e4SLinus Torvalds struct sctp_chunk *tchunk = NULL;
12549dbc15f0SRobert P. J. Day struct list_head *lchunk, *transport_list, *temp;
12551da177e4SLinus Torvalds __u32 sack_ctsn, ctsn, tsn;
12561da177e4SLinus Torvalds __u32 highest_tsn, highest_new_tsn;
12571da177e4SLinus Torvalds __u32 sack_a_rwnd;
125895c96174SEric Dumazet unsigned int outstanding;
12591da177e4SLinus Torvalds struct sctp_transport *primary = asoc->peer.primary_path;
12601da177e4SLinus Torvalds int count_of_newacks = 0;
12612cd9b822SVlad Yasevich int gap_ack_blocks;
1262ea862c8dSVlad Yasevich u8 accum_moved = 0;
12631da177e4SLinus Torvalds
12641da177e4SLinus Torvalds /* Grab the association's destination address list. */
12651da177e4SLinus Torvalds transport_list = &asoc->peer.transport_addr_list;
12661da177e4SLinus Torvalds
1267f643ee29SKevin Kou /* SCTP path tracepoint for congestion control debugging. */
1268f398efc1SKevin Kou if (trace_sctp_probe_path_enabled()) {
1269f398efc1SKevin Kou list_for_each_entry(transport, transport_list, transports)
1270f643ee29SKevin Kou trace_sctp_probe_path(transport, asoc);
1271f643ee29SKevin Kou }
1272f643ee29SKevin Kou
12731da177e4SLinus Torvalds sack_ctsn = ntohl(sack->cum_tsn_ack);
12742cd9b822SVlad Yasevich gap_ack_blocks = ntohs(sack->num_gap_ack_blocks);
1275196d6759SMichele Baldessari asoc->stats.gapcnt += gap_ack_blocks;
12761da177e4SLinus Torvalds /*
12771da177e4SLinus Torvalds * SFR-CACC algorithm:
12781da177e4SLinus Torvalds * On receipt of a SACK the sender SHOULD execute the
12791da177e4SLinus Torvalds * following statements.
12801da177e4SLinus Torvalds *
12811da177e4SLinus Torvalds * 1) If the cumulative ack in the SACK passes next tsn_at_change
12821da177e4SLinus Torvalds * on the current primary, the CHANGEOVER_ACTIVE flag SHOULD be
12831da177e4SLinus Torvalds * cleared. The CYCLING_CHANGEOVER flag SHOULD also be cleared for
12841da177e4SLinus Torvalds * all destinations.
12851da177e4SLinus Torvalds * 2) If the SACK contains gap acks and the flag CHANGEOVER_ACTIVE
12861da177e4SLinus Torvalds * is set the receiver of the SACK MUST take the following actions:
12871da177e4SLinus Torvalds *
12881da177e4SLinus Torvalds * A) Initialize the cacc_saw_newack to 0 for all destination
12891da177e4SLinus Torvalds * addresses.
1290ab5216a5SVlad Yasevich *
1291ab5216a5SVlad Yasevich * Only bother if changeover_active is set. Otherwise, this is
1292ab5216a5SVlad Yasevich * totally suboptimal to do on every SACK.
12931da177e4SLinus Torvalds */
1294ab5216a5SVlad Yasevich if (primary->cacc.changeover_active) {
1295ab5216a5SVlad Yasevich u8 clear_cycling = 0;
1296ab5216a5SVlad Yasevich
1297ab5216a5SVlad Yasevich if (TSN_lte(primary->cacc.next_tsn_at_change, sack_ctsn)) {
1298ab5216a5SVlad Yasevich primary->cacc.changeover_active = 0;
1299ab5216a5SVlad Yasevich clear_cycling = 1;
1300ab5216a5SVlad Yasevich }
1301ab5216a5SVlad Yasevich
1302ab5216a5SVlad Yasevich if (clear_cycling || gap_ack_blocks) {
1303ab5216a5SVlad Yasevich list_for_each_entry(transport, transport_list,
1304ab5216a5SVlad Yasevich transports) {
1305ab5216a5SVlad Yasevich if (clear_cycling)
1306ab5216a5SVlad Yasevich transport->cacc.cycling_changeover = 0;
1307ab5216a5SVlad Yasevich if (gap_ack_blocks)
13081da177e4SLinus Torvalds transport->cacc.cacc_saw_newack = 0;
13091da177e4SLinus Torvalds }
13101da177e4SLinus Torvalds }
1311ab5216a5SVlad Yasevich }
13121da177e4SLinus Torvalds
13131da177e4SLinus Torvalds /* Get the highest TSN in the sack. */
13141da177e4SLinus Torvalds highest_tsn = sack_ctsn;
1315*9789c1c6SXin Long if (gap_ack_blocks) {
1316*9789c1c6SXin Long union sctp_sack_variable *frags =
1317*9789c1c6SXin Long (union sctp_sack_variable *)(sack + 1);
1318*9789c1c6SXin Long
13192cd9b822SVlad Yasevich highest_tsn += ntohs(frags[gap_ack_blocks - 1].gab.end);
1320*9789c1c6SXin Long }
13211da177e4SLinus Torvalds
1322bfa0d984SVlad Yasevich if (TSN_lt(asoc->highest_sacked, highest_tsn))
13231da177e4SLinus Torvalds asoc->highest_sacked = highest_tsn;
13241da177e4SLinus Torvalds
1325bfa0d984SVlad Yasevich highest_new_tsn = sack_ctsn;
13262cd9b822SVlad Yasevich
13271da177e4SLinus Torvalds /* Run through the retransmit queue. Credit bytes received
13281da177e4SLinus Torvalds * and free those chunks that we can.
13291da177e4SLinus Torvalds */
1330edfee033SNicolas Dichtel sctp_check_transmitted(q, &q->retransmit, NULL, NULL, sack, &highest_new_tsn);
13311da177e4SLinus Torvalds
13321da177e4SLinus Torvalds /* Run through the transmitted queue.
13331da177e4SLinus Torvalds * Credit bytes received and free those chunks which we can.
13341da177e4SLinus Torvalds *
13351da177e4SLinus Torvalds * This is a MASSIVE candidate for optimization.
13361da177e4SLinus Torvalds */
13379dbc15f0SRobert P. J. Day list_for_each_entry(transport, transport_list, transports) {
13381da177e4SLinus Torvalds sctp_check_transmitted(q, &transport->transmitted,
1339edfee033SNicolas Dichtel transport, &chunk->source, sack,
1340edfee033SNicolas Dichtel &highest_new_tsn);
13411da177e4SLinus Torvalds /*
13421da177e4SLinus Torvalds * SFR-CACC algorithm:
13431da177e4SLinus Torvalds * C) Let count_of_newacks be the number of
13441da177e4SLinus Torvalds * destinations for which cacc_saw_newack is set.
13451da177e4SLinus Torvalds */
13461da177e4SLinus Torvalds if (transport->cacc.cacc_saw_newack)
13471da177e4SLinus Torvalds count_of_newacks++;
13481da177e4SLinus Torvalds }
13491da177e4SLinus Torvalds
1350ea862c8dSVlad Yasevich /* Move the Cumulative TSN Ack Point if appropriate. */
1351ea862c8dSVlad Yasevich if (TSN_lt(asoc->ctsn_ack_point, sack_ctsn)) {
1352ea862c8dSVlad Yasevich asoc->ctsn_ack_point = sack_ctsn;
1353ea862c8dSVlad Yasevich accum_moved = 1;
1354ea862c8dSVlad Yasevich }
1355ea862c8dSVlad Yasevich
13562cd9b822SVlad Yasevich if (gap_ack_blocks) {
1357ea862c8dSVlad Yasevich
1358ea862c8dSVlad Yasevich if (asoc->fast_recovery && accum_moved)
1359ea862c8dSVlad Yasevich highest_new_tsn = highest_tsn;
1360ea862c8dSVlad Yasevich
13612cd9b822SVlad Yasevich list_for_each_entry(transport, transport_list, transports)
13621da177e4SLinus Torvalds sctp_mark_missing(q, &transport->transmitted, transport,
13631da177e4SLinus Torvalds highest_new_tsn, count_of_newacks);
13641da177e4SLinus Torvalds }
13651da177e4SLinus Torvalds
13661da177e4SLinus Torvalds /* Update unack_data field in the assoc. */
13671da177e4SLinus Torvalds sctp_sack_update_unack_data(asoc, sack);
13681da177e4SLinus Torvalds
13691da177e4SLinus Torvalds ctsn = asoc->ctsn_ack_point;
13701da177e4SLinus Torvalds
13711da177e4SLinus Torvalds /* Throw away stuff rotting on the sack queue. */
13721da177e4SLinus Torvalds list_for_each_safe(lchunk, temp, &q->sacked) {
13731da177e4SLinus Torvalds tchunk = list_entry(lchunk, struct sctp_chunk,
13741da177e4SLinus Torvalds transmitted_list);
13751da177e4SLinus Torvalds tsn = ntohl(tchunk->subh.data_hdr->tsn);
13765f9646c3SVlad Yasevich if (TSN_lte(tsn, ctsn)) {
13775f9646c3SVlad Yasevich list_del_init(&tchunk->transmitted_list);
1378be4947bfSXin Long if (asoc->peer.prsctp_capable &&
13798dbdf1f5SXin Long SCTP_PR_PRIO_ENABLED(chunk->sinfo.sinfo_flags))
13808dbdf1f5SXin Long asoc->sent_cnt_removable--;
13811da177e4SLinus Torvalds sctp_chunk_free(tchunk);
13821da177e4SLinus Torvalds }
13835f9646c3SVlad Yasevich }
13841da177e4SLinus Torvalds
13851da177e4SLinus Torvalds /* ii) Set rwnd equal to the newly received a_rwnd minus the
13861da177e4SLinus Torvalds * number of bytes still outstanding after processing the
13871da177e4SLinus Torvalds * Cumulative TSN Ack and the Gap Ack Blocks.
13881da177e4SLinus Torvalds */
13891da177e4SLinus Torvalds
13901da177e4SLinus Torvalds sack_a_rwnd = ntohl(sack->a_rwnd);
13918a0d19c5Slucien asoc->peer.zero_window_announced = !sack_a_rwnd;
13921da177e4SLinus Torvalds outstanding = q->outstanding_bytes;
13931da177e4SLinus Torvalds
13941da177e4SLinus Torvalds if (outstanding < sack_a_rwnd)
13951da177e4SLinus Torvalds sack_a_rwnd -= outstanding;
13961da177e4SLinus Torvalds else
13971da177e4SLinus Torvalds sack_a_rwnd = 0;
13981da177e4SLinus Torvalds
13991da177e4SLinus Torvalds asoc->peer.rwnd = sack_a_rwnd;
14001da177e4SLinus Torvalds
14018e0c3b73SXin Long asoc->stream.si->generate_ftsn(q, sack_ctsn);
14021da177e4SLinus Torvalds
1403bb33381dSDaniel Borkmann pr_debug("%s: sack cumulative tsn ack:0x%x\n", __func__, sack_ctsn);
1404bb33381dSDaniel Borkmann pr_debug("%s: cumulative tsn ack of assoc:%p is 0x%x, "
1405bb33381dSDaniel Borkmann "advertised peer ack point:0x%x\n", __func__, asoc, ctsn,
1406bb33381dSDaniel Borkmann asoc->adv_peer_ack_point);
14071da177e4SLinus Torvalds
1408619a60eeSVlad Yasevich return sctp_outq_is_empty(q);
1409619a60eeSVlad Yasevich }
1410619a60eeSVlad Yasevich
1411619a60eeSVlad Yasevich /* Is the outqueue empty?
1412619a60eeSVlad Yasevich * The queue is empty when we have not pending data, no in-flight data
1413619a60eeSVlad Yasevich * and nothing pending retransmissions.
14141da177e4SLinus Torvalds */
sctp_outq_is_empty(const struct sctp_outq * q)14151da177e4SLinus Torvalds int sctp_outq_is_empty(const struct sctp_outq *q)
14161da177e4SLinus Torvalds {
1417619a60eeSVlad Yasevich return q->out_qlen == 0 && q->outstanding_bytes == 0 &&
1418619a60eeSVlad Yasevich list_empty(&q->retransmit);
14191da177e4SLinus Torvalds }
14201da177e4SLinus Torvalds
14211da177e4SLinus Torvalds /********************************************************************
14221da177e4SLinus Torvalds * 2nd Level Abstractions
14231da177e4SLinus Torvalds ********************************************************************/
14241da177e4SLinus Torvalds
14251da177e4SLinus Torvalds /* Go through a transport's transmitted list or the association's retransmit
14261da177e4SLinus Torvalds * list and move chunks that are acked by the Cumulative TSN Ack to q->sacked.
14271da177e4SLinus Torvalds * The retransmit list will not have an associated transport.
14281da177e4SLinus Torvalds *
14291da177e4SLinus Torvalds * I added coherent debug information output. --xguo
14301da177e4SLinus Torvalds *
14311da177e4SLinus Torvalds * Instead of printing 'sacked' or 'kept' for each TSN on the
14321da177e4SLinus Torvalds * transmitted_queue, we print a range: SACKED: TSN1-TSN2, TSN3, TSN4-TSN5.
14331da177e4SLinus Torvalds * KEPT TSN6-TSN7, etc.
14341da177e4SLinus Torvalds */
sctp_check_transmitted(struct sctp_outq * q,struct list_head * transmitted_queue,struct sctp_transport * transport,union sctp_addr * saddr,struct sctp_sackhdr * sack,__u32 * highest_new_tsn_in_sack)14351da177e4SLinus Torvalds static void sctp_check_transmitted(struct sctp_outq *q,
14361da177e4SLinus Torvalds struct list_head *transmitted_queue,
14371da177e4SLinus Torvalds struct sctp_transport *transport,
1438edfee033SNicolas Dichtel union sctp_addr *saddr,
14391da177e4SLinus Torvalds struct sctp_sackhdr *sack,
1440bfa0d984SVlad Yasevich __u32 *highest_new_tsn_in_sack)
14411da177e4SLinus Torvalds {
14421da177e4SLinus Torvalds struct list_head *lchunk;
14431da177e4SLinus Torvalds struct sctp_chunk *tchunk;
14441da177e4SLinus Torvalds struct list_head tlist;
14451da177e4SLinus Torvalds __u32 tsn;
14461da177e4SLinus Torvalds __u32 sack_ctsn;
14471da177e4SLinus Torvalds __u32 rtt;
14481da177e4SLinus Torvalds __u8 restart_timer = 0;
14491da177e4SLinus Torvalds int bytes_acked = 0;
145031b02e15SVlad Yasevich int migrate_bytes = 0;
14518c2f414aSDaniel Borkmann bool forward_progress = false;
14521da177e4SLinus Torvalds
14531da177e4SLinus Torvalds sack_ctsn = ntohl(sack->cum_tsn_ack);
14541da177e4SLinus Torvalds
14551da177e4SLinus Torvalds INIT_LIST_HEAD(&tlist);
14561da177e4SLinus Torvalds
14571da177e4SLinus Torvalds /* The while loop will skip empty transmitted queues. */
14581da177e4SLinus Torvalds while (NULL != (lchunk = sctp_list_dequeue(transmitted_queue))) {
14591da177e4SLinus Torvalds tchunk = list_entry(lchunk, struct sctp_chunk,
14601da177e4SLinus Torvalds transmitted_list);
14611da177e4SLinus Torvalds
14621da177e4SLinus Torvalds if (sctp_chunk_abandoned(tchunk)) {
14631da177e4SLinus Torvalds /* Move the chunk to abandoned list. */
14641da177e4SLinus Torvalds sctp_insert_list(&q->abandoned, lchunk);
14658c4a2d41SVlad Yasevich
14668c4a2d41SVlad Yasevich /* If this chunk has not been acked, stop
14678c4a2d41SVlad Yasevich * considering it as 'outstanding'.
14688c4a2d41SVlad Yasevich */
1469d30fc512SXin Long if (transmitted_queue != &q->retransmit &&
1470d30fc512SXin Long !tchunk->tsn_gap_acked) {
147131b02e15SVlad Yasevich if (tchunk->transport)
14728c4a2d41SVlad Yasevich tchunk->transport->flight_size -=
14738c4a2d41SVlad Yasevich sctp_data_size(tchunk);
14748c4a2d41SVlad Yasevich q->outstanding_bytes -= sctp_data_size(tchunk);
14758c4a2d41SVlad Yasevich }
14761da177e4SLinus Torvalds continue;
14771da177e4SLinus Torvalds }
14781da177e4SLinus Torvalds
14791da177e4SLinus Torvalds tsn = ntohl(tchunk->subh.data_hdr->tsn);
14801da177e4SLinus Torvalds if (sctp_acked(sack, tsn)) {
14811da177e4SLinus Torvalds /* If this queue is the retransmit queue, the
14821da177e4SLinus Torvalds * retransmit timer has already reclaimed
14831da177e4SLinus Torvalds * the outstanding bytes for this chunk, so only
14841da177e4SLinus Torvalds * count bytes associated with a transport.
14851da177e4SLinus Torvalds */
148651446780SMarcelo Ricardo Leitner if (transport && !tchunk->tsn_gap_acked) {
14871da177e4SLinus Torvalds /* If this chunk is being used for RTT
14881da177e4SLinus Torvalds * measurement, calculate the RTT and update
14891da177e4SLinus Torvalds * the RTO using this value.
14901da177e4SLinus Torvalds *
14911da177e4SLinus Torvalds * 6.3.1 C5) Karn's algorithm: RTT measurements
14921da177e4SLinus Torvalds * MUST NOT be made using packets that were
14931da177e4SLinus Torvalds * retransmitted (and thus for which it is
14941da177e4SLinus Torvalds * ambiguous whether the reply was for the
14951da177e4SLinus Torvalds * first instance of the packet or a later
14961da177e4SLinus Torvalds * instance).
14971da177e4SLinus Torvalds */
149851446780SMarcelo Ricardo Leitner if (!sctp_chunk_retransmitted(tchunk) &&
14991da177e4SLinus Torvalds tchunk->rtt_in_progress) {
15004c9f5d53SVlad Yasevich tchunk->rtt_in_progress = 0;
15011da177e4SLinus Torvalds rtt = jiffies - tchunk->sent_at;
15021da177e4SLinus Torvalds sctp_transport_update_rto(transport,
15031da177e4SLinus Torvalds rtt);
15041da177e4SLinus Torvalds }
150551446780SMarcelo Ricardo Leitner
150651446780SMarcelo Ricardo Leitner if (TSN_lte(tsn, sack_ctsn)) {
150751446780SMarcelo Ricardo Leitner /*
150851446780SMarcelo Ricardo Leitner * SFR-CACC algorithm:
150951446780SMarcelo Ricardo Leitner * 2) If the SACK contains gap acks
151051446780SMarcelo Ricardo Leitner * and the flag CHANGEOVER_ACTIVE is
151151446780SMarcelo Ricardo Leitner * set the receiver of the SACK MUST
151251446780SMarcelo Ricardo Leitner * take the following action:
151351446780SMarcelo Ricardo Leitner *
151451446780SMarcelo Ricardo Leitner * B) For each TSN t being acked that
151551446780SMarcelo Ricardo Leitner * has not been acked in any SACK so
151651446780SMarcelo Ricardo Leitner * far, set cacc_saw_newack to 1 for
151751446780SMarcelo Ricardo Leitner * the destination that the TSN was
151851446780SMarcelo Ricardo Leitner * sent to.
151951446780SMarcelo Ricardo Leitner */
152051446780SMarcelo Ricardo Leitner if (sack->num_gap_ack_blocks &&
152151446780SMarcelo Ricardo Leitner q->asoc->peer.primary_path->cacc.
152251446780SMarcelo Ricardo Leitner changeover_active)
152351446780SMarcelo Ricardo Leitner transport->cacc.cacc_saw_newack
152451446780SMarcelo Ricardo Leitner = 1;
152551446780SMarcelo Ricardo Leitner }
15261da177e4SLinus Torvalds }
152731b02e15SVlad Yasevich
152831b02e15SVlad Yasevich /* If the chunk hasn't been marked as ACKED,
152931b02e15SVlad Yasevich * mark it and account bytes_acked if the
153031b02e15SVlad Yasevich * chunk had a valid transport (it will not
153131b02e15SVlad Yasevich * have a transport if ASCONF had deleted it
153231b02e15SVlad Yasevich * while DATA was outstanding).
153331b02e15SVlad Yasevich */
153431b02e15SVlad Yasevich if (!tchunk->tsn_gap_acked) {
153531b02e15SVlad Yasevich tchunk->tsn_gap_acked = 1;
1536d6c41614SChang Xiangzhong if (TSN_lt(*highest_new_tsn_in_sack, tsn))
1537bfa0d984SVlad Yasevich *highest_new_tsn_in_sack = tsn;
153831b02e15SVlad Yasevich bytes_acked += sctp_data_size(tchunk);
153931b02e15SVlad Yasevich if (!tchunk->transport)
154031b02e15SVlad Yasevich migrate_bytes += sctp_data_size(tchunk);
15418c2f414aSDaniel Borkmann forward_progress = true;
154231b02e15SVlad Yasevich }
154331b02e15SVlad Yasevich
15441da177e4SLinus Torvalds if (TSN_lte(tsn, sack_ctsn)) {
15451da177e4SLinus Torvalds /* RFC 2960 6.3.2 Retransmission Timer Rules
15461da177e4SLinus Torvalds *
15471da177e4SLinus Torvalds * R3) Whenever a SACK is received
15481da177e4SLinus Torvalds * that acknowledges the DATA chunk
15491da177e4SLinus Torvalds * with the earliest outstanding TSN
15501da177e4SLinus Torvalds * for that address, restart T3-rtx
15511da177e4SLinus Torvalds * timer for that address with its
15521da177e4SLinus Torvalds * current RTO.
15531da177e4SLinus Torvalds */
15541da177e4SLinus Torvalds restart_timer = 1;
15558c2f414aSDaniel Borkmann forward_progress = true;
15561da177e4SLinus Torvalds
15571da177e4SLinus Torvalds list_add_tail(&tchunk->transmitted_list,
15581da177e4SLinus Torvalds &q->sacked);
15591da177e4SLinus Torvalds } else {
15601da177e4SLinus Torvalds /* RFC2960 7.2.4, sctpimpguide-05 2.8.2
15611da177e4SLinus Torvalds * M2) Each time a SACK arrives reporting
15621da177e4SLinus Torvalds * 'Stray DATA chunk(s)' record the highest TSN
15631da177e4SLinus Torvalds * reported as newly acknowledged, call this
15641da177e4SLinus Torvalds * value 'HighestTSNinSack'. A newly
15651da177e4SLinus Torvalds * acknowledged DATA chunk is one not
15661da177e4SLinus Torvalds * previously acknowledged in a SACK.
15671da177e4SLinus Torvalds *
15681da177e4SLinus Torvalds * When the SCTP sender of data receives a SACK
15691da177e4SLinus Torvalds * chunk that acknowledges, for the first time,
15701da177e4SLinus Torvalds * the receipt of a DATA chunk, all the still
15711da177e4SLinus Torvalds * unacknowledged DATA chunks whose TSN is
15721da177e4SLinus Torvalds * older than that newly acknowledged DATA
15731da177e4SLinus Torvalds * chunk, are qualified as 'Stray DATA chunks'.
15741da177e4SLinus Torvalds */
15751da177e4SLinus Torvalds list_add_tail(lchunk, &tlist);
15761da177e4SLinus Torvalds }
15771da177e4SLinus Torvalds } else {
15781da177e4SLinus Torvalds if (tchunk->tsn_gap_acked) {
1579bb33381dSDaniel Borkmann pr_debug("%s: receiver reneged on data TSN:0x%x\n",
1580bb33381dSDaniel Borkmann __func__, tsn);
1581bb33381dSDaniel Borkmann
15821da177e4SLinus Torvalds tchunk->tsn_gap_acked = 0;
15831da177e4SLinus Torvalds
158431b02e15SVlad Yasevich if (tchunk->transport)
15851da177e4SLinus Torvalds bytes_acked -= sctp_data_size(tchunk);
15861da177e4SLinus Torvalds
15871da177e4SLinus Torvalds /* RFC 2960 6.3.2 Retransmission Timer Rules
15881da177e4SLinus Torvalds *
15891da177e4SLinus Torvalds * R4) Whenever a SACK is received missing a
15901da177e4SLinus Torvalds * TSN that was previously acknowledged via a
15911da177e4SLinus Torvalds * Gap Ack Block, start T3-rtx for the
15921da177e4SLinus Torvalds * destination address to which the DATA
15931da177e4SLinus Torvalds * chunk was originally
15941da177e4SLinus Torvalds * transmitted if it is not already running.
15951da177e4SLinus Torvalds */
15961da177e4SLinus Torvalds restart_timer = 1;
15971da177e4SLinus Torvalds }
15981da177e4SLinus Torvalds
15991da177e4SLinus Torvalds list_add_tail(lchunk, &tlist);
16001da177e4SLinus Torvalds }
16011da177e4SLinus Torvalds }
16021da177e4SLinus Torvalds
16031da177e4SLinus Torvalds if (transport) {
16041da177e4SLinus Torvalds if (bytes_acked) {
1605f8d96052SThomas Graf struct sctp_association *asoc = transport->asoc;
1606f8d96052SThomas Graf
160731b02e15SVlad Yasevich /* We may have counted DATA that was migrated
160831b02e15SVlad Yasevich * to this transport due to DEL-IP operation.
160931b02e15SVlad Yasevich * Subtract those bytes, since the were never
161031b02e15SVlad Yasevich * send on this transport and shouldn't be
161131b02e15SVlad Yasevich * credited to this transport.
161231b02e15SVlad Yasevich */
161331b02e15SVlad Yasevich bytes_acked -= migrate_bytes;
161431b02e15SVlad Yasevich
16151da177e4SLinus Torvalds /* 8.2. When an outstanding TSN is acknowledged,
16161da177e4SLinus Torvalds * the endpoint shall clear the error counter of
16171da177e4SLinus Torvalds * the destination transport address to which the
16181da177e4SLinus Torvalds * DATA chunk was last sent.
16191da177e4SLinus Torvalds * The association's overall error counter is
16201da177e4SLinus Torvalds * also cleared.
16211da177e4SLinus Torvalds */
16221da177e4SLinus Torvalds transport->error_count = 0;
16231da177e4SLinus Torvalds transport->asoc->overall_error_count = 0;
16248c2f414aSDaniel Borkmann forward_progress = true;
16251da177e4SLinus Torvalds
1626f8d96052SThomas Graf /*
1627f8d96052SThomas Graf * While in SHUTDOWN PENDING, we may have started
1628f8d96052SThomas Graf * the T5 shutdown guard timer after reaching the
1629f8d96052SThomas Graf * retransmission limit. Stop that timer as soon
1630f8d96052SThomas Graf * as the receiver acknowledged any data.
1631f8d96052SThomas Graf */
1632f8d96052SThomas Graf if (asoc->state == SCTP_STATE_SHUTDOWN_PENDING &&
1633f8d96052SThomas Graf del_timer(&asoc->timers
1634f8d96052SThomas Graf [SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD]))
1635f8d96052SThomas Graf sctp_association_put(asoc);
1636f8d96052SThomas Graf
16371da177e4SLinus Torvalds /* Mark the destination transport address as
16381da177e4SLinus Torvalds * active if it is not so marked.
16391da177e4SLinus Torvalds */
1640edfee033SNicolas Dichtel if ((transport->state == SCTP_INACTIVE ||
1641edfee033SNicolas Dichtel transport->state == SCTP_UNCONFIRMED) &&
1642edfee033SNicolas Dichtel sctp_cmp_addr_exact(&transport->ipaddr, saddr)) {
16431da177e4SLinus Torvalds sctp_assoc_control_transport(
16441da177e4SLinus Torvalds transport->asoc,
16451da177e4SLinus Torvalds transport,
16461da177e4SLinus Torvalds SCTP_TRANSPORT_UP,
16471da177e4SLinus Torvalds SCTP_RECEIVED_SACK);
16481da177e4SLinus Torvalds }
16491da177e4SLinus Torvalds
16501da177e4SLinus Torvalds sctp_transport_raise_cwnd(transport, sack_ctsn,
16511da177e4SLinus Torvalds bytes_acked);
16521da177e4SLinus Torvalds
16531da177e4SLinus Torvalds transport->flight_size -= bytes_acked;
16548b73a07cSGui Jianfeng if (transport->flight_size == 0)
16558b73a07cSGui Jianfeng transport->partial_bytes_acked = 0;
165631b02e15SVlad Yasevich q->outstanding_bytes -= bytes_acked + migrate_bytes;
16571da177e4SLinus Torvalds } else {
16581da177e4SLinus Torvalds /* RFC 2960 6.1, sctpimpguide-06 2.15.2
16591da177e4SLinus Torvalds * When a sender is doing zero window probing, it
16601da177e4SLinus Torvalds * should not timeout the association if it continues
16611da177e4SLinus Torvalds * to receive new packets from the receiver. The
16621da177e4SLinus Torvalds * reason is that the receiver MAY keep its window
16631da177e4SLinus Torvalds * closed for an indefinite time.
16641da177e4SLinus Torvalds * A sender is doing zero window probing when the
16651da177e4SLinus Torvalds * receiver's advertised window is zero, and there is
16661da177e4SLinus Torvalds * only one data chunk in flight to the receiver.
1667f8d96052SThomas Graf *
1668f8d96052SThomas Graf * Allow the association to timeout while in SHUTDOWN
1669f8d96052SThomas Graf * PENDING or SHUTDOWN RECEIVED in case the receiver
1670f8d96052SThomas Graf * stays in zero window mode forever.
16711da177e4SLinus Torvalds */
16721da177e4SLinus Torvalds if (!q->asoc->peer.rwnd &&
16731da177e4SLinus Torvalds !list_empty(&tlist) &&
1674f8d96052SThomas Graf (sack_ctsn+2 == q->asoc->next_tsn) &&
1675f8d96052SThomas Graf q->asoc->state < SCTP_STATE_SHUTDOWN_PENDING) {
1676bb33381dSDaniel Borkmann pr_debug("%s: sack received for zero window "
1677bb33381dSDaniel Borkmann "probe:%u\n", __func__, sack_ctsn);
1678bb33381dSDaniel Borkmann
16791da177e4SLinus Torvalds q->asoc->overall_error_count = 0;
16801da177e4SLinus Torvalds transport->error_count = 0;
16811da177e4SLinus Torvalds }
16821da177e4SLinus Torvalds }
16831da177e4SLinus Torvalds
16841da177e4SLinus Torvalds /* RFC 2960 6.3.2 Retransmission Timer Rules
16851da177e4SLinus Torvalds *
16861da177e4SLinus Torvalds * R2) Whenever all outstanding data sent to an address have
16871da177e4SLinus Torvalds * been acknowledged, turn off the T3-rtx timer of that
16881da177e4SLinus Torvalds * address.
16891da177e4SLinus Torvalds */
16901da177e4SLinus Torvalds if (!transport->flight_size) {
169125cc4ae9SYing Xue if (del_timer(&transport->T3_rtx_timer))
16921da177e4SLinus Torvalds sctp_transport_put(transport);
16931da177e4SLinus Torvalds } else if (restart_timer) {
16941da177e4SLinus Torvalds if (!mod_timer(&transport->T3_rtx_timer,
16951da177e4SLinus Torvalds jiffies + transport->rto))
16961da177e4SLinus Torvalds sctp_transport_hold(transport);
16971da177e4SLinus Torvalds }
16988c2f414aSDaniel Borkmann
16998c2f414aSDaniel Borkmann if (forward_progress) {
17008c2f414aSDaniel Borkmann if (transport->dst)
1701c86a773cSJulian Anastasov sctp_transport_dst_confirm(transport);
17028c2f414aSDaniel Borkmann }
17031da177e4SLinus Torvalds }
17041da177e4SLinus Torvalds
17051da177e4SLinus Torvalds list_splice(&tlist, transmitted_queue);
17061da177e4SLinus Torvalds }
17071da177e4SLinus Torvalds
17081da177e4SLinus Torvalds /* Mark chunks as missing and consequently may get retransmitted. */
sctp_mark_missing(struct sctp_outq * q,struct list_head * transmitted_queue,struct sctp_transport * transport,__u32 highest_new_tsn_in_sack,int count_of_newacks)17091da177e4SLinus Torvalds static void sctp_mark_missing(struct sctp_outq *q,
17101da177e4SLinus Torvalds struct list_head *transmitted_queue,
17111da177e4SLinus Torvalds struct sctp_transport *transport,
17121da177e4SLinus Torvalds __u32 highest_new_tsn_in_sack,
17131da177e4SLinus Torvalds int count_of_newacks)
17141da177e4SLinus Torvalds {
17151da177e4SLinus Torvalds struct sctp_chunk *chunk;
17161da177e4SLinus Torvalds __u32 tsn;
17171da177e4SLinus Torvalds char do_fast_retransmit = 0;
1718ea862c8dSVlad Yasevich struct sctp_association *asoc = q->asoc;
1719ea862c8dSVlad Yasevich struct sctp_transport *primary = asoc->peer.primary_path;
17201da177e4SLinus Torvalds
17219dbc15f0SRobert P. J. Day list_for_each_entry(chunk, transmitted_queue, transmitted_list) {
17221da177e4SLinus Torvalds
17231da177e4SLinus Torvalds tsn = ntohl(chunk->subh.data_hdr->tsn);
17241da177e4SLinus Torvalds
17251da177e4SLinus Torvalds /* RFC 2960 7.2.4, sctpimpguide-05 2.8.2 M3) Examine all
17261da177e4SLinus Torvalds * 'Unacknowledged TSN's', if the TSN number of an
17271da177e4SLinus Torvalds * 'Unacknowledged TSN' is smaller than the 'HighestTSNinSack'
17281da177e4SLinus Torvalds * value, increment the 'TSN.Missing.Report' count on that
17291da177e4SLinus Torvalds * chunk if it has NOT been fast retransmitted or marked for
17301da177e4SLinus Torvalds * fast retransmit already.
17311da177e4SLinus Torvalds */
1732c226ef9bSNeil Horman if (chunk->fast_retransmit == SCTP_CAN_FRTX &&
17331da177e4SLinus Torvalds !chunk->tsn_gap_acked &&
17341da177e4SLinus Torvalds TSN_lt(tsn, highest_new_tsn_in_sack)) {
17351da177e4SLinus Torvalds
17361da177e4SLinus Torvalds /* SFR-CACC may require us to skip marking
17371da177e4SLinus Torvalds * this chunk as missing.
17381da177e4SLinus Torvalds */
1739f246a7b7SVlad Yasevich if (!transport || !sctp_cacc_skip(primary,
1740f246a7b7SVlad Yasevich chunk->transport,
17411da177e4SLinus Torvalds count_of_newacks, tsn)) {
17421da177e4SLinus Torvalds chunk->tsn_missing_report++;
17431da177e4SLinus Torvalds
1744bb33381dSDaniel Borkmann pr_debug("%s: tsn:0x%x missing counter:%d\n",
1745bb33381dSDaniel Borkmann __func__, tsn, chunk->tsn_missing_report);
17461da177e4SLinus Torvalds }
17471da177e4SLinus Torvalds }
17481da177e4SLinus Torvalds /*
17491da177e4SLinus Torvalds * M4) If any DATA chunk is found to have a
17501da177e4SLinus Torvalds * 'TSN.Missing.Report'
175127852c26SVlad Yasevich * value larger than or equal to 3, mark that chunk for
17521da177e4SLinus Torvalds * retransmission and start the fast retransmit procedure.
17531da177e4SLinus Torvalds */
17541da177e4SLinus Torvalds
175527852c26SVlad Yasevich if (chunk->tsn_missing_report >= 3) {
1756c226ef9bSNeil Horman chunk->fast_retransmit = SCTP_NEED_FRTX;
17571da177e4SLinus Torvalds do_fast_retransmit = 1;
17581da177e4SLinus Torvalds }
17591da177e4SLinus Torvalds }
17601da177e4SLinus Torvalds
17611da177e4SLinus Torvalds if (transport) {
17621da177e4SLinus Torvalds if (do_fast_retransmit)
17631da177e4SLinus Torvalds sctp_retransmit(q, transport, SCTP_RTXR_FAST_RTX);
17641da177e4SLinus Torvalds
1765bb33381dSDaniel Borkmann pr_debug("%s: transport:%p, cwnd:%d, ssthresh:%d, "
1766bb33381dSDaniel Borkmann "flight_size:%d, pba:%d\n", __func__, transport,
1767bb33381dSDaniel Borkmann transport->cwnd, transport->ssthresh,
1768bb33381dSDaniel Borkmann transport->flight_size, transport->partial_bytes_acked);
17691da177e4SLinus Torvalds }
17701da177e4SLinus Torvalds }
17711da177e4SLinus Torvalds
17721da177e4SLinus Torvalds /* Is the given TSN acked by this packet? */
sctp_acked(struct sctp_sackhdr * sack,__u32 tsn)17731da177e4SLinus Torvalds static int sctp_acked(struct sctp_sackhdr *sack, __u32 tsn)
17741da177e4SLinus Torvalds {
17751da177e4SLinus Torvalds __u32 ctsn = ntohl(sack->cum_tsn_ack);
1776afd93b7bSXin Long union sctp_sack_variable *frags;
1777afd93b7bSXin Long __u16 tsn_offset, blocks;
1778afd93b7bSXin Long int i;
17791da177e4SLinus Torvalds
17801da177e4SLinus Torvalds if (TSN_lte(tsn, ctsn))
17811da177e4SLinus Torvalds goto pass;
17821da177e4SLinus Torvalds
17835884f35fSMarcelo Ricardo Leitner /* 3.3.4 Selective Acknowledgment (SACK) (3):
17841da177e4SLinus Torvalds *
17851da177e4SLinus Torvalds * Gap Ack Blocks:
17861da177e4SLinus Torvalds * These fields contain the Gap Ack Blocks. They are repeated
17871da177e4SLinus Torvalds * for each Gap Ack Block up to the number of Gap Ack Blocks
17881da177e4SLinus Torvalds * defined in the Number of Gap Ack Blocks field. All DATA
17891da177e4SLinus Torvalds * chunks with TSNs greater than or equal to (Cumulative TSN
17901da177e4SLinus Torvalds * Ack + Gap Ack Block Start) and less than or equal to
17911da177e4SLinus Torvalds * (Cumulative TSN Ack + Gap Ack Block End) of each Gap Ack
17921da177e4SLinus Torvalds * Block are assumed to have been received correctly.
17931da177e4SLinus Torvalds */
17941da177e4SLinus Torvalds
1795*9789c1c6SXin Long frags = (union sctp_sack_variable *)(sack + 1);
1796a3007446SMarcelo Ricardo Leitner blocks = ntohs(sack->num_gap_ack_blocks);
1797a3007446SMarcelo Ricardo Leitner tsn_offset = tsn - ctsn;
1798a3007446SMarcelo Ricardo Leitner for (i = 0; i < blocks; ++i) {
1799a3007446SMarcelo Ricardo Leitner if (tsn_offset >= ntohs(frags[i].gab.start) &&
1800a3007446SMarcelo Ricardo Leitner tsn_offset <= ntohs(frags[i].gab.end))
18011da177e4SLinus Torvalds goto pass;
18021da177e4SLinus Torvalds }
18031da177e4SLinus Torvalds
18041da177e4SLinus Torvalds return 0;
18051da177e4SLinus Torvalds pass:
18061da177e4SLinus Torvalds return 1;
18071da177e4SLinus Torvalds }
18081da177e4SLinus Torvalds
sctp_get_skip_pos(struct sctp_fwdtsn_skip * skiplist,int nskips,__be16 stream)18091da177e4SLinus Torvalds static inline int sctp_get_skip_pos(struct sctp_fwdtsn_skip *skiplist,
18109f81bcd9SAl Viro int nskips, __be16 stream)
18111da177e4SLinus Torvalds {
18121da177e4SLinus Torvalds int i;
18131da177e4SLinus Torvalds
18141da177e4SLinus Torvalds for (i = 0; i < nskips; i++) {
18151da177e4SLinus Torvalds if (skiplist[i].stream == stream)
18161da177e4SLinus Torvalds return i;
18171da177e4SLinus Torvalds }
18181da177e4SLinus Torvalds return i;
18191da177e4SLinus Torvalds }
18201da177e4SLinus Torvalds
18211da177e4SLinus Torvalds /* Create and add a fwdtsn chunk to the outq's control queue if needed. */
sctp_generate_fwdtsn(struct sctp_outq * q,__u32 ctsn)18228e0c3b73SXin Long void sctp_generate_fwdtsn(struct sctp_outq *q, __u32 ctsn)
18231da177e4SLinus Torvalds {
18241da177e4SLinus Torvalds struct sctp_association *asoc = q->asoc;
18251da177e4SLinus Torvalds struct sctp_chunk *ftsn_chunk = NULL;
18261da177e4SLinus Torvalds struct sctp_fwdtsn_skip ftsn_skip_arr[10];
18271da177e4SLinus Torvalds int nskips = 0;
18281da177e4SLinus Torvalds int skip_pos = 0;
18291da177e4SLinus Torvalds __u32 tsn;
18301da177e4SLinus Torvalds struct sctp_chunk *chunk;
18311da177e4SLinus Torvalds struct list_head *lchunk, *temp;
18321da177e4SLinus Torvalds
183376595024SWei Yongjun if (!asoc->peer.prsctp_capable)
183476595024SWei Yongjun return;
183576595024SWei Yongjun
18361da177e4SLinus Torvalds /* PR-SCTP C1) Let SackCumAck be the Cumulative TSN ACK carried in the
18371da177e4SLinus Torvalds * received SACK.
18381da177e4SLinus Torvalds *
18391da177e4SLinus Torvalds * If (Advanced.Peer.Ack.Point < SackCumAck), then update
18401da177e4SLinus Torvalds * Advanced.Peer.Ack.Point to be equal to SackCumAck.
18411da177e4SLinus Torvalds */
18421da177e4SLinus Torvalds if (TSN_lt(asoc->adv_peer_ack_point, ctsn))
18431da177e4SLinus Torvalds asoc->adv_peer_ack_point = ctsn;
18441da177e4SLinus Torvalds
18451da177e4SLinus Torvalds /* PR-SCTP C2) Try to further advance the "Advanced.Peer.Ack.Point"
18461da177e4SLinus Torvalds * locally, that is, to move "Advanced.Peer.Ack.Point" up as long as
18471da177e4SLinus Torvalds * the chunk next in the out-queue space is marked as "abandoned" as
18481da177e4SLinus Torvalds * shown in the following example:
18491da177e4SLinus Torvalds *
18501da177e4SLinus Torvalds * Assuming that a SACK arrived with the Cumulative TSN ACK 102
18511da177e4SLinus Torvalds * and the Advanced.Peer.Ack.Point is updated to this value:
18521da177e4SLinus Torvalds *
18531da177e4SLinus Torvalds * out-queue at the end of ==> out-queue after Adv.Ack.Point
18541da177e4SLinus Torvalds * normal SACK processing local advancement
18551da177e4SLinus Torvalds * ... ...
18561da177e4SLinus Torvalds * Adv.Ack.Pt-> 102 acked 102 acked
18571da177e4SLinus Torvalds * 103 abandoned 103 abandoned
18581da177e4SLinus Torvalds * 104 abandoned Adv.Ack.P-> 104 abandoned
18591da177e4SLinus Torvalds * 105 105
18601da177e4SLinus Torvalds * 106 acked 106 acked
18611da177e4SLinus Torvalds * ... ...
18621da177e4SLinus Torvalds *
18631da177e4SLinus Torvalds * In this example, the data sender successfully advanced the
18641da177e4SLinus Torvalds * "Advanced.Peer.Ack.Point" from 102 to 104 locally.
18651da177e4SLinus Torvalds */
18661da177e4SLinus Torvalds list_for_each_safe(lchunk, temp, &q->abandoned) {
18671da177e4SLinus Torvalds chunk = list_entry(lchunk, struct sctp_chunk,
18681da177e4SLinus Torvalds transmitted_list);
18691da177e4SLinus Torvalds tsn = ntohl(chunk->subh.data_hdr->tsn);
18701da177e4SLinus Torvalds
18711da177e4SLinus Torvalds /* Remove any chunks in the abandoned queue that are acked by
18721da177e4SLinus Torvalds * the ctsn.
18731da177e4SLinus Torvalds */
18741da177e4SLinus Torvalds if (TSN_lte(tsn, ctsn)) {
18751da177e4SLinus Torvalds list_del_init(lchunk);
18761da177e4SLinus Torvalds sctp_chunk_free(chunk);
18771da177e4SLinus Torvalds } else {
18781da177e4SLinus Torvalds if (TSN_lte(tsn, asoc->adv_peer_ack_point+1)) {
18791da177e4SLinus Torvalds asoc->adv_peer_ack_point = tsn;
18801da177e4SLinus Torvalds if (chunk->chunk_hdr->flags &
18811da177e4SLinus Torvalds SCTP_DATA_UNORDERED)
18821da177e4SLinus Torvalds continue;
18831da177e4SLinus Torvalds skip_pos = sctp_get_skip_pos(&ftsn_skip_arr[0],
18841da177e4SLinus Torvalds nskips,
18851da177e4SLinus Torvalds chunk->subh.data_hdr->stream);
18861da177e4SLinus Torvalds ftsn_skip_arr[skip_pos].stream =
18871da177e4SLinus Torvalds chunk->subh.data_hdr->stream;
18881da177e4SLinus Torvalds ftsn_skip_arr[skip_pos].ssn =
18891da177e4SLinus Torvalds chunk->subh.data_hdr->ssn;
18901da177e4SLinus Torvalds if (skip_pos == nskips)
18911da177e4SLinus Torvalds nskips++;
18921da177e4SLinus Torvalds if (nskips == 10)
18931da177e4SLinus Torvalds break;
18941da177e4SLinus Torvalds } else
18951da177e4SLinus Torvalds break;
18961da177e4SLinus Torvalds }
18971da177e4SLinus Torvalds }
18981da177e4SLinus Torvalds
18991da177e4SLinus Torvalds /* PR-SCTP C3) If, after step C1 and C2, the "Advanced.Peer.Ack.Point"
19001da177e4SLinus Torvalds * is greater than the Cumulative TSN ACK carried in the received
19011da177e4SLinus Torvalds * SACK, the data sender MUST send the data receiver a FORWARD TSN
19021da177e4SLinus Torvalds * chunk containing the latest value of the
19031da177e4SLinus Torvalds * "Advanced.Peer.Ack.Point".
19041da177e4SLinus Torvalds *
19051da177e4SLinus Torvalds * C4) For each "abandoned" TSN the sender of the FORWARD TSN SHOULD
19061da177e4SLinus Torvalds * list each stream and sequence number in the forwarded TSN. This
19071da177e4SLinus Torvalds * information will enable the receiver to easily find any
19081da177e4SLinus Torvalds * stranded TSN's waiting on stream reorder queues. Each stream
19091da177e4SLinus Torvalds * SHOULD only be reported once; this means that if multiple
19101da177e4SLinus Torvalds * abandoned messages occur in the same stream then only the
19111da177e4SLinus Torvalds * highest abandoned stream sequence number is reported. If the
19121da177e4SLinus Torvalds * total size of the FORWARD TSN does NOT fit in a single MTU then
19131da177e4SLinus Torvalds * the sender of the FORWARD TSN SHOULD lower the
19141da177e4SLinus Torvalds * Advanced.Peer.Ack.Point to the last TSN that will fit in a
19151da177e4SLinus Torvalds * single MTU.
19161da177e4SLinus Torvalds */
19171da177e4SLinus Torvalds if (asoc->adv_peer_ack_point > ctsn)
19181da177e4SLinus Torvalds ftsn_chunk = sctp_make_fwdtsn(asoc, asoc->adv_peer_ack_point,
19191da177e4SLinus Torvalds nskips, &ftsn_skip_arr[0]);
19201da177e4SLinus Torvalds
19211da177e4SLinus Torvalds if (ftsn_chunk) {
192279af02c2SDavid S. Miller list_add_tail(&ftsn_chunk->list, &q->control_chunk_list);
19234e7696d9SXin Long SCTP_INC_STATS(asoc->base.net, SCTP_MIB_OUTCTRLCHUNKS);
19241da177e4SLinus Torvalds }
19251da177e4SLinus Torvalds }
1926