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44#include <linux/types.h>
45#include <linux/kernel.h>
46#include <linux/wait.h>
47#include <linux/time.h>
48#include <linux/ip.h>
49#include <linux/ipv6.h>
50#include <linux/init.h>
51#include <net/inet_ecn.h>
52#include <net/icmp.h>
53#include <net/net_namespace.h>
54
55#ifndef TEST_FRAME
56#include <net/tcp.h>
57#endif
58
59#include <linux/socket.h>
60#include <net/sock.h>
61
62#include <net/sctp/sctp.h>
63#include <net/sctp/sm.h>
64#include <net/sctp/checksum.h>
65
66
67static sctp_xmit_t sctp_packet_append_data(struct sctp_packet *packet,
68 struct sctp_chunk *chunk);
69
70
71
72
73struct sctp_packet *sctp_packet_config(struct sctp_packet *packet,
74 __u32 vtag, int ecn_capable)
75{
76 struct sctp_chunk *chunk = NULL;
77
78 SCTP_DEBUG_PRINTK("%s: packet:%p vtag:0x%x\n", __func__,
79 packet, vtag);
80
81 packet->vtag = vtag;
82 packet->has_cookie_echo = 0;
83 packet->has_sack = 0;
84 packet->has_auth = 0;
85 packet->has_data = 0;
86 packet->ipfragok = 0;
87 packet->auth = NULL;
88
89 if (ecn_capable && sctp_packet_empty(packet)) {
90 chunk = sctp_get_ecne_prepend(packet->transport->asoc);
91
92
93
94
95 if (chunk)
96 sctp_packet_append_chunk(packet, chunk);
97 }
98
99 return packet;
100}
101
102
103struct sctp_packet *sctp_packet_init(struct sctp_packet *packet,
104 struct sctp_transport *transport,
105 __u16 sport, __u16 dport)
106{
107 struct sctp_association *asoc = transport->asoc;
108 size_t overhead;
109
110 SCTP_DEBUG_PRINTK("%s: packet:%p transport:%p\n", __func__,
111 packet, transport);
112
113 packet->transport = transport;
114 packet->source_port = sport;
115 packet->destination_port = dport;
116 INIT_LIST_HEAD(&packet->chunk_list);
117 if (asoc) {
118 struct sctp_sock *sp = sctp_sk(asoc->base.sk);
119 overhead = sp->pf->af->net_header_len;
120 } else {
121 overhead = sizeof(struct ipv6hdr);
122 }
123 overhead += sizeof(struct sctphdr);
124 packet->overhead = overhead;
125 packet->size = overhead;
126 packet->vtag = 0;
127 packet->has_cookie_echo = 0;
128 packet->has_sack = 0;
129 packet->has_auth = 0;
130 packet->has_data = 0;
131 packet->ipfragok = 0;
132 packet->malloced = 0;
133 packet->auth = NULL;
134 return packet;
135}
136
137
138void sctp_packet_free(struct sctp_packet *packet)
139{
140 struct sctp_chunk *chunk, *tmp;
141
142 SCTP_DEBUG_PRINTK("%s: packet:%p\n", __func__, packet);
143
144 list_for_each_entry_safe(chunk, tmp, &packet->chunk_list, list) {
145 list_del_init(&chunk->list);
146 sctp_chunk_free(chunk);
147 }
148
149 if (packet->malloced)
150 kfree(packet);
151}
152
153
154
155
156
157
158
159
160sctp_xmit_t sctp_packet_transmit_chunk(struct sctp_packet *packet,
161 struct sctp_chunk *chunk,
162 int one_packet)
163{
164 sctp_xmit_t retval;
165 int error = 0;
166
167 SCTP_DEBUG_PRINTK("%s: packet:%p chunk:%p\n", __func__,
168 packet, chunk);
169
170 switch ((retval = (sctp_packet_append_chunk(packet, chunk)))) {
171 case SCTP_XMIT_PMTU_FULL:
172 if (!packet->has_cookie_echo) {
173 error = sctp_packet_transmit(packet);
174 if (error < 0)
175 chunk->skb->sk->sk_err = -error;
176
177
178
179
180 if (!one_packet)
181 retval = sctp_packet_append_chunk(packet,
182 chunk);
183 }
184 break;
185
186 case SCTP_XMIT_RWND_FULL:
187 case SCTP_XMIT_OK:
188 case SCTP_XMIT_NAGLE_DELAY:
189 break;
190 }
191
192 return retval;
193}
194
195
196static sctp_xmit_t sctp_packet_bundle_auth(struct sctp_packet *pkt,
197 struct sctp_chunk *chunk)
198{
199 struct sctp_association *asoc = pkt->transport->asoc;
200 struct sctp_chunk *auth;
201 sctp_xmit_t retval = SCTP_XMIT_OK;
202
203
204 if (!asoc)
205 return retval;
206
207
208
209
210 if (chunk->chunk_hdr->type == SCTP_CID_AUTH || pkt->auth)
211 return retval;
212
213
214
215
216 if (!chunk->auth)
217 return retval;
218
219 auth = sctp_make_auth(asoc);
220 if (!auth)
221 return retval;
222
223 retval = sctp_packet_append_chunk(pkt, auth);
224
225 return retval;
226}
227
228
229static sctp_xmit_t sctp_packet_bundle_sack(struct sctp_packet *pkt,
230 struct sctp_chunk *chunk)
231{
232 sctp_xmit_t retval = SCTP_XMIT_OK;
233
234
235
236
237 if (sctp_chunk_is_data(chunk) && !pkt->has_sack &&
238 !pkt->has_cookie_echo) {
239 struct sctp_association *asoc;
240 asoc = pkt->transport->asoc;
241
242 if (asoc->a_rwnd > asoc->rwnd) {
243 struct sctp_chunk *sack;
244 asoc->a_rwnd = asoc->rwnd;
245 sack = sctp_make_sack(asoc);
246 if (sack) {
247 struct timer_list *timer;
248 retval = sctp_packet_append_chunk(pkt, sack);
249 asoc->peer.sack_needed = 0;
250 timer = &asoc->timers[SCTP_EVENT_TIMEOUT_SACK];
251 if (timer_pending(timer) && del_timer(timer))
252 sctp_association_put(asoc);
253 }
254 }
255 }
256 return retval;
257}
258
259
260
261
262sctp_xmit_t sctp_packet_append_chunk(struct sctp_packet *packet,
263 struct sctp_chunk *chunk)
264{
265 sctp_xmit_t retval = SCTP_XMIT_OK;
266 __u16 chunk_len = WORD_ROUND(ntohs(chunk->chunk_hdr->length));
267 size_t psize;
268 size_t pmtu;
269 int too_big;
270
271 SCTP_DEBUG_PRINTK("%s: packet:%p chunk:%p\n", __func__, packet,
272 chunk);
273
274
275 retval = sctp_packet_bundle_auth(packet, chunk);
276 if (retval != SCTP_XMIT_OK)
277 goto finish;
278
279
280 retval = sctp_packet_bundle_sack(packet, chunk);
281 if (retval != SCTP_XMIT_OK)
282 goto finish;
283
284 psize = packet->size;
285 pmtu = ((packet->transport->asoc) ?
286 (packet->transport->asoc->pathmtu) :
287 (packet->transport->pathmtu));
288
289 too_big = (psize + chunk_len > pmtu);
290
291
292 if (too_big) {
293
294
295
296
297
298
299
300
301 if (sctp_packet_empty(packet) || !sctp_chunk_is_data(chunk) ||
302 (!packet->has_data && chunk->auth)) {
303
304
305
306
307 packet->ipfragok = 1;
308 goto append;
309
310 } else {
311 retval = SCTP_XMIT_PMTU_FULL;
312 goto finish;
313 }
314 }
315
316append:
317
318
319
320
321
322
323
324 switch (chunk->chunk_hdr->type) {
325 case SCTP_CID_DATA:
326 retval = sctp_packet_append_data(packet, chunk);
327
328 packet->has_sack = 1;
329
330 packet->has_auth = 1;
331
332 packet->has_data = 1;
333 if (SCTP_XMIT_OK != retval)
334 goto finish;
335 break;
336 case SCTP_CID_COOKIE_ECHO:
337 packet->has_cookie_echo = 1;
338 break;
339
340 case SCTP_CID_SACK:
341 packet->has_sack = 1;
342 break;
343
344 case SCTP_CID_AUTH:
345 packet->has_auth = 1;
346 packet->auth = chunk;
347 break;
348 }
349
350
351 list_add_tail(&chunk->list, &packet->chunk_list);
352 packet->size += chunk_len;
353 chunk->transport = packet->transport;
354finish:
355 return retval;
356}
357
358
359
360
361
362
363int sctp_packet_transmit(struct sctp_packet *packet)
364{
365 struct sctp_transport *tp = packet->transport;
366 struct sctp_association *asoc = tp->asoc;
367 struct sctphdr *sh;
368 __be32 crc32 = __constant_cpu_to_be32(0);
369 struct sk_buff *nskb;
370 struct sctp_chunk *chunk, *tmp;
371 struct sock *sk;
372 int err = 0;
373 int padding;
374 __u8 has_data = 0;
375 struct dst_entry *dst = tp->dst;
376 unsigned char *auth = NULL;
377 __u32 cksum_buf_len = sizeof(struct sctphdr);
378
379 SCTP_DEBUG_PRINTK("%s: packet:%p\n", __func__, packet);
380
381
382 if (list_empty(&packet->chunk_list))
383 return err;
384
385
386 chunk = list_entry(packet->chunk_list.next, struct sctp_chunk, list);
387 sk = chunk->skb->sk;
388
389
390 nskb = alloc_skb(packet->size + LL_MAX_HEADER, GFP_ATOMIC);
391 if (!nskb)
392 goto nomem;
393
394
395 skb_reserve(nskb, packet->overhead + LL_MAX_HEADER);
396
397
398
399
400 skb_set_owner_w(nskb, sk);
401
402
403 if (!dst || (dst->obsolete > 1)) {
404 dst_release(dst);
405 sctp_transport_route(tp, NULL, sctp_sk(sk));
406 if (asoc && (asoc->param_flags & SPP_PMTUD_ENABLE)) {
407 sctp_assoc_sync_pmtu(asoc);
408 }
409 }
410 nskb->dst = dst_clone(tp->dst);
411 if (!nskb->dst)
412 goto no_route;
413 dst = nskb->dst;
414
415
416 sh = (struct sctphdr *)skb_push(nskb, sizeof(struct sctphdr));
417 sh->source = htons(packet->source_port);
418 sh->dest = htons(packet->destination_port);
419
420
421
422
423
424
425
426
427
428 sh->vtag = htonl(packet->vtag);
429 sh->checksum = 0;
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450 SCTP_DEBUG_PRINTK("***sctp_transmit_packet***\n");
451 list_for_each_entry_safe(chunk, tmp, &packet->chunk_list, list) {
452 list_del_init(&chunk->list);
453 if (sctp_chunk_is_data(chunk)) {
454
455 if (!chunk->has_tsn) {
456 sctp_chunk_assign_ssn(chunk);
457 sctp_chunk_assign_tsn(chunk);
458
459
460
461
462
463
464
465
466 if (!tp->rto_pending) {
467 chunk->rtt_in_progress = 1;
468 tp->rto_pending = 1;
469 }
470 } else
471 chunk->resent = 1;
472
473 chunk->sent_at = jiffies;
474 has_data = 1;
475 }
476
477 padding = WORD_ROUND(chunk->skb->len) - chunk->skb->len;
478 if (padding)
479 memset(skb_put(chunk->skb, padding), 0, padding);
480
481
482
483
484
485 if (chunk == packet->auth)
486 auth = skb_tail_pointer(nskb);
487
488 cksum_buf_len += chunk->skb->len;
489 memcpy(skb_put(nskb, chunk->skb->len),
490 chunk->skb->data, chunk->skb->len);
491
492 SCTP_DEBUG_PRINTK("%s %p[%s] %s 0x%x, %s %d, %s %d, %s %d\n",
493 "*** Chunk", chunk,
494 sctp_cname(SCTP_ST_CHUNK(
495 chunk->chunk_hdr->type)),
496 chunk->has_tsn ? "TSN" : "No TSN",
497 chunk->has_tsn ?
498 ntohl(chunk->subh.data_hdr->tsn) : 0,
499 "length", ntohs(chunk->chunk_hdr->length),
500 "chunk->skb->len", chunk->skb->len,
501 "rtt_in_progress", chunk->rtt_in_progress);
502
503
504
505
506
507
508 if (!sctp_chunk_is_data(chunk))
509 sctp_chunk_free(chunk);
510 }
511
512
513
514
515
516
517
518
519
520
521 if (auth)
522 sctp_auth_calculate_hmac(asoc, nskb,
523 (struct sctp_auth_chunk *)auth,
524 GFP_ATOMIC);
525
526
527
528
529
530
531
532
533 if (!(dst->dev->features & NETIF_F_NO_CSUM)) {
534 crc32 = sctp_start_cksum((__u8 *)sh, cksum_buf_len);
535 crc32 = sctp_end_cksum(crc32);
536 } else
537 nskb->ip_summed = CHECKSUM_UNNECESSARY;
538
539
540
541
542 sh->checksum = crc32;
543
544
545
546
547
548
549
550
551
552
553
554
555
556 (*tp->af_specific->ecn_capable)(nskb->sk);
557
558
559
560
561
562
563
564 if (asoc && asoc->peer.last_sent_to != tp) {
565
566
567
568 asoc->peer.last_sent_to = tp;
569 }
570
571 if (has_data) {
572 struct timer_list *timer;
573 unsigned long timeout;
574
575 tp->last_time_used = jiffies;
576
577
578 if (sctp_state(asoc, ESTABLISHED) && asoc->autoclose) {
579 timer = &asoc->timers[SCTP_EVENT_TIMEOUT_AUTOCLOSE];
580 timeout = asoc->timeouts[SCTP_EVENT_TIMEOUT_AUTOCLOSE];
581
582 if (!mod_timer(timer, jiffies + timeout))
583 sctp_association_hold(asoc);
584 }
585 }
586
587 SCTP_DEBUG_PRINTK("***sctp_transmit_packet*** skb len %d\n",
588 nskb->len);
589
590 nskb->local_df = packet->ipfragok;
591 (*tp->af_specific->sctp_xmit)(nskb, tp);
592
593out:
594 packet->size = packet->overhead;
595 return err;
596no_route:
597 kfree_skb(nskb);
598 IP_INC_STATS_BH(&init_net, IPSTATS_MIB_OUTNOROUTES);
599
600
601
602
603
604
605
606
607
608err:
609
610
611
612
613 list_for_each_entry_safe(chunk, tmp, &packet->chunk_list, list) {
614 list_del_init(&chunk->list);
615 if (!sctp_chunk_is_data(chunk))
616 sctp_chunk_free(chunk);
617 }
618 goto out;
619nomem:
620 err = -ENOMEM;
621 goto err;
622}
623
624
625
626
627
628
629static sctp_xmit_t sctp_packet_append_data(struct sctp_packet *packet,
630 struct sctp_chunk *chunk)
631{
632 sctp_xmit_t retval = SCTP_XMIT_OK;
633 size_t datasize, rwnd, inflight;
634 struct sctp_transport *transport = packet->transport;
635 __u32 max_burst_bytes;
636 struct sctp_association *asoc = transport->asoc;
637 struct sctp_sock *sp = sctp_sk(asoc->base.sk);
638 struct sctp_outq *q = &asoc->outqueue;
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653 rwnd = asoc->peer.rwnd;
654 inflight = asoc->outqueue.outstanding_bytes;
655
656 datasize = sctp_data_size(chunk);
657
658 if (datasize > rwnd) {
659 if (inflight > 0) {
660
661
662
663 retval = SCTP_XMIT_RWND_FULL;
664 goto finish;
665 }
666 }
667
668
669
670
671
672
673
674
675
676 max_burst_bytes = asoc->max_burst * asoc->pathmtu;
677 if ((transport->flight_size + max_burst_bytes) < transport->cwnd) {
678 transport->cwnd = transport->flight_size + max_burst_bytes;
679 SCTP_DEBUG_PRINTK("%s: cwnd limited by max_burst: "
680 "transport: %p, cwnd: %d, "
681 "ssthresh: %d, flight_size: %d, "
682 "pba: %d\n",
683 __func__, transport,
684 transport->cwnd,
685 transport->ssthresh,
686 transport->flight_size,
687 transport->partial_bytes_acked);
688 }
689
690
691
692
693
694
695
696
697
698
699
700
701
702 if (chunk->fast_retransmit != SCTP_NEED_FRTX)
703 if (transport->flight_size >= transport->cwnd) {
704 retval = SCTP_XMIT_RWND_FULL;
705 goto finish;
706 }
707
708
709
710
711
712
713 if (!sp->nodelay && sctp_packet_empty(packet) &&
714 q->outstanding_bytes && sctp_state(asoc, ESTABLISHED)) {
715 unsigned len = datasize + q->out_qlen;
716
717
718
719
720
721 if (len < asoc->frag_point) {
722 retval = SCTP_XMIT_NAGLE_DELAY;
723 goto finish;
724 }
725 }
726
727
728 transport->flight_size += datasize;
729
730
731 asoc->outqueue.outstanding_bytes += datasize;
732
733
734
735
736
737
738
739 datasize += sizeof(struct sk_buff);
740 if (datasize < rwnd)
741 rwnd -= datasize;
742 else
743 rwnd = 0;
744
745 asoc->peer.rwnd = rwnd;
746
747 if (!asoc->peer.prsctp_capable)
748 chunk->msg->can_abandon = 0;
749
750finish:
751 return retval;
752}