Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* SCTP kernel reference Implementation |
| 2 | * (C) Copyright IBM Corp. 2001, 2004 |
| 3 | * Copyright (c) 1999-2000 Cisco, Inc. |
| 4 | * Copyright (c) 1999-2001 Motorola, Inc. |
| 5 | * Copyright (c) 2001 Intel Corp. |
| 6 | * Copyright (c) 2001 Nokia, Inc. |
| 7 | * Copyright (c) 2001 La Monte H.P. Yarroll |
| 8 | * |
| 9 | * This abstraction carries sctp events to the ULP (sockets). |
| 10 | * |
| 11 | * The SCTP reference implementation is free software; |
| 12 | * you can redistribute it and/or modify it under the terms of |
| 13 | * the GNU General Public License as published by |
| 14 | * the Free Software Foundation; either version 2, or (at your option) |
| 15 | * any later version. |
| 16 | * |
| 17 | * The SCTP reference implementation is distributed in the hope that it |
| 18 | * will be useful, but WITHOUT ANY WARRANTY; without even the implied |
| 19 | * ************************ |
| 20 | * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. |
| 21 | * See the GNU General Public License for more details. |
| 22 | * |
| 23 | * You should have received a copy of the GNU General Public License |
| 24 | * along with GNU CC; see the file COPYING. If not, write to |
| 25 | * the Free Software Foundation, 59 Temple Place - Suite 330, |
| 26 | * Boston, MA 02111-1307, USA. |
| 27 | * |
| 28 | * Please send any bug reports or fixes you make to the |
| 29 | * email address(es): |
| 30 | * lksctp developers <lksctp-developers@lists.sourceforge.net> |
| 31 | * |
| 32 | * Or submit a bug report through the following website: |
| 33 | * http://www.sf.net/projects/lksctp |
| 34 | * |
| 35 | * Written or modified by: |
| 36 | * Jon Grimm <jgrimm@us.ibm.com> |
| 37 | * La Monte H.P. Yarroll <piggy@acm.org> |
| 38 | * Sridhar Samudrala <sri@us.ibm.com> |
| 39 | * |
| 40 | * Any bugs reported given to us we will try to fix... any fixes shared will |
| 41 | * be incorporated into the next SCTP release. |
| 42 | */ |
| 43 | |
| 44 | #include <linux/types.h> |
| 45 | #include <linux/skbuff.h> |
| 46 | #include <net/sock.h> |
| 47 | #include <net/sctp/structs.h> |
| 48 | #include <net/sctp/sctp.h> |
| 49 | #include <net/sctp/sm.h> |
| 50 | |
| 51 | /* Forward declarations for internal helpers. */ |
| 52 | static struct sctp_ulpevent * sctp_ulpq_reasm(struct sctp_ulpq *ulpq, |
David S. Miller | 8728b83 | 2005-08-09 19:25:21 -0700 | [diff] [blame] | 53 | struct sctp_ulpevent *); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 54 | static struct sctp_ulpevent * sctp_ulpq_order(struct sctp_ulpq *, |
David S. Miller | 8728b83 | 2005-08-09 19:25:21 -0700 | [diff] [blame] | 55 | struct sctp_ulpevent *); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 56 | |
| 57 | /* 1st Level Abstractions */ |
| 58 | |
| 59 | /* Initialize a ULP queue from a block of memory. */ |
| 60 | struct sctp_ulpq *sctp_ulpq_init(struct sctp_ulpq *ulpq, |
| 61 | struct sctp_association *asoc) |
| 62 | { |
| 63 | memset(ulpq, 0, sizeof(struct sctp_ulpq)); |
| 64 | |
| 65 | ulpq->asoc = asoc; |
| 66 | skb_queue_head_init(&ulpq->reasm); |
| 67 | skb_queue_head_init(&ulpq->lobby); |
| 68 | ulpq->pd_mode = 0; |
| 69 | ulpq->malloced = 0; |
| 70 | |
| 71 | return ulpq; |
| 72 | } |
| 73 | |
| 74 | |
| 75 | /* Flush the reassembly and ordering queues. */ |
Vlad Yasevich | 0b58a81 | 2007-03-19 17:01:17 -0700 | [diff] [blame] | 76 | void sctp_ulpq_flush(struct sctp_ulpq *ulpq) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 77 | { |
| 78 | struct sk_buff *skb; |
| 79 | struct sctp_ulpevent *event; |
| 80 | |
| 81 | while ((skb = __skb_dequeue(&ulpq->lobby)) != NULL) { |
| 82 | event = sctp_skb2event(skb); |
| 83 | sctp_ulpevent_free(event); |
| 84 | } |
| 85 | |
| 86 | while ((skb = __skb_dequeue(&ulpq->reasm)) != NULL) { |
| 87 | event = sctp_skb2event(skb); |
| 88 | sctp_ulpevent_free(event); |
| 89 | } |
| 90 | |
| 91 | } |
| 92 | |
| 93 | /* Dispose of a ulpqueue. */ |
| 94 | void sctp_ulpq_free(struct sctp_ulpq *ulpq) |
| 95 | { |
| 96 | sctp_ulpq_flush(ulpq); |
| 97 | if (ulpq->malloced) |
| 98 | kfree(ulpq); |
| 99 | } |
| 100 | |
| 101 | /* Process an incoming DATA chunk. */ |
| 102 | int sctp_ulpq_tail_data(struct sctp_ulpq *ulpq, struct sctp_chunk *chunk, |
Al Viro | dd0fc66 | 2005-10-07 07:46:04 +0100 | [diff] [blame] | 103 | gfp_t gfp) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 104 | { |
| 105 | struct sk_buff_head temp; |
| 106 | sctp_data_chunk_t *hdr; |
| 107 | struct sctp_ulpevent *event; |
| 108 | |
| 109 | hdr = (sctp_data_chunk_t *) chunk->chunk_hdr; |
| 110 | |
| 111 | /* Create an event from the incoming chunk. */ |
| 112 | event = sctp_ulpevent_make_rcvmsg(chunk->asoc, chunk, gfp); |
| 113 | if (!event) |
| 114 | return -ENOMEM; |
| 115 | |
| 116 | /* Do reassembly if needed. */ |
| 117 | event = sctp_ulpq_reasm(ulpq, event); |
| 118 | |
| 119 | /* Do ordering if needed. */ |
| 120 | if ((event) && (event->msg_flags & MSG_EOR)){ |
| 121 | /* Create a temporary list to collect chunks on. */ |
| 122 | skb_queue_head_init(&temp); |
| 123 | __skb_queue_tail(&temp, sctp_event2skb(event)); |
| 124 | |
| 125 | event = sctp_ulpq_order(ulpq, event); |
| 126 | } |
| 127 | |
David S. Miller | 8728b83 | 2005-08-09 19:25:21 -0700 | [diff] [blame] | 128 | /* Send event to the ULP. 'event' is the sctp_ulpevent for |
| 129 | * very first SKB on the 'temp' list. |
| 130 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 131 | if (event) |
| 132 | sctp_ulpq_tail_event(ulpq, event); |
| 133 | |
| 134 | return 0; |
| 135 | } |
| 136 | |
| 137 | /* Add a new event for propagation to the ULP. */ |
| 138 | /* Clear the partial delivery mode for this socket. Note: This |
| 139 | * assumes that no association is currently in partial delivery mode. |
| 140 | */ |
Vlad Yasevich | b6e1331 | 2007-04-20 12:23:15 -0700 | [diff] [blame] | 141 | int sctp_clear_pd(struct sock *sk, struct sctp_association *asoc) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 142 | { |
| 143 | struct sctp_sock *sp = sctp_sk(sk); |
| 144 | |
Vlad Yasevich | b6e1331 | 2007-04-20 12:23:15 -0700 | [diff] [blame] | 145 | if (atomic_dec_and_test(&sp->pd_mode)) { |
| 146 | /* This means there are no other associations in PD, so |
| 147 | * we can go ahead and clear out the lobby in one shot |
| 148 | */ |
| 149 | if (!skb_queue_empty(&sp->pd_lobby)) { |
| 150 | struct list_head *list; |
| 151 | sctp_skb_list_tail(&sp->pd_lobby, &sk->sk_receive_queue); |
| 152 | list = (struct list_head *)&sctp_sk(sk)->pd_lobby; |
| 153 | INIT_LIST_HEAD(list); |
| 154 | return 1; |
| 155 | } |
| 156 | } else { |
| 157 | /* There are other associations in PD, so we only need to |
| 158 | * pull stuff out of the lobby that belongs to the |
| 159 | * associations that is exiting PD (all of its notifications |
| 160 | * are posted here). |
| 161 | */ |
| 162 | if (!skb_queue_empty(&sp->pd_lobby) && asoc) { |
| 163 | struct sk_buff *skb, *tmp; |
| 164 | struct sctp_ulpevent *event; |
| 165 | |
| 166 | sctp_skb_for_each(skb, &sp->pd_lobby, tmp) { |
| 167 | event = sctp_skb2event(skb); |
| 168 | if (event->asoc == asoc) { |
| 169 | __skb_unlink(skb, &sp->pd_lobby); |
| 170 | __skb_queue_tail(&sk->sk_receive_queue, |
| 171 | skb); |
| 172 | } |
| 173 | } |
| 174 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 175 | } |
Vlad Yasevich | b6e1331 | 2007-04-20 12:23:15 -0700 | [diff] [blame] | 176 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 177 | return 0; |
| 178 | } |
| 179 | |
Vlad Yasevich | d49d91d | 2007-03-23 11:32:00 -0700 | [diff] [blame] | 180 | /* Set the pd_mode on the socket and ulpq */ |
| 181 | static void sctp_ulpq_set_pd(struct sctp_ulpq *ulpq) |
| 182 | { |
| 183 | struct sctp_sock *sp = sctp_sk(ulpq->asoc->base.sk); |
| 184 | |
| 185 | atomic_inc(&sp->pd_mode); |
| 186 | ulpq->pd_mode = 1; |
| 187 | } |
| 188 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 189 | /* Clear the pd_mode and restart any pending messages waiting for delivery. */ |
| 190 | static int sctp_ulpq_clear_pd(struct sctp_ulpq *ulpq) |
| 191 | { |
| 192 | ulpq->pd_mode = 0; |
Vlad Yasevich | b6e1331 | 2007-04-20 12:23:15 -0700 | [diff] [blame] | 193 | return sctp_clear_pd(ulpq->asoc->base.sk, ulpq->asoc); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 194 | } |
| 195 | |
David S. Miller | 8728b83 | 2005-08-09 19:25:21 -0700 | [diff] [blame] | 196 | /* If the SKB of 'event' is on a list, it is the first such member |
| 197 | * of that list. |
| 198 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 199 | int sctp_ulpq_tail_event(struct sctp_ulpq *ulpq, struct sctp_ulpevent *event) |
| 200 | { |
| 201 | struct sock *sk = ulpq->asoc->base.sk; |
David S. Miller | 8728b83 | 2005-08-09 19:25:21 -0700 | [diff] [blame] | 202 | struct sk_buff_head *queue, *skb_list; |
| 203 | struct sk_buff *skb = sctp_event2skb(event); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 204 | int clear_pd = 0; |
| 205 | |
David S. Miller | 8728b83 | 2005-08-09 19:25:21 -0700 | [diff] [blame] | 206 | skb_list = (struct sk_buff_head *) skb->prev; |
| 207 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 208 | /* If the socket is just going to throw this away, do not |
| 209 | * even try to deliver it. |
| 210 | */ |
| 211 | if (sock_flag(sk, SOCK_DEAD) || (sk->sk_shutdown & RCV_SHUTDOWN)) |
| 212 | goto out_free; |
| 213 | |
| 214 | /* Check if the user wishes to receive this event. */ |
| 215 | if (!sctp_ulpevent_is_enabled(event, &sctp_sk(sk)->subscribe)) |
| 216 | goto out_free; |
| 217 | |
| 218 | /* If we are in partial delivery mode, post to the lobby until |
| 219 | * partial delivery is cleared, unless, of course _this_ is |
| 220 | * the association the cause of the partial delivery. |
| 221 | */ |
| 222 | |
Vlad Yasevich | b6e1331 | 2007-04-20 12:23:15 -0700 | [diff] [blame] | 223 | if (atomic_read(&sctp_sk(sk)->pd_mode) == 0) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 224 | queue = &sk->sk_receive_queue; |
Vlad Yasevich | b6e1331 | 2007-04-20 12:23:15 -0700 | [diff] [blame] | 225 | } else { |
| 226 | if (ulpq->pd_mode) { |
| 227 | /* If the association is in partial delivery, we |
| 228 | * need to finish delivering the partially processed |
| 229 | * packet before passing any other data. This is |
| 230 | * because we don't truly support stream interleaving. |
| 231 | */ |
| 232 | if ((event->msg_flags & MSG_NOTIFICATION) || |
| 233 | (SCTP_DATA_NOT_FRAG == |
| 234 | (event->msg_flags & SCTP_DATA_FRAG_MASK))) |
| 235 | queue = &sctp_sk(sk)->pd_lobby; |
| 236 | else { |
| 237 | clear_pd = event->msg_flags & MSG_EOR; |
| 238 | queue = &sk->sk_receive_queue; |
| 239 | } |
| 240 | } else { |
| 241 | /* |
| 242 | * If fragment interleave is enabled, we |
| 243 | * can queue this to the recieve queue instead |
| 244 | * of the lobby. |
| 245 | */ |
| 246 | if (sctp_sk(sk)->frag_interleave) |
| 247 | queue = &sk->sk_receive_queue; |
| 248 | else |
| 249 | queue = &sctp_sk(sk)->pd_lobby; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 250 | } |
Vlad Yasevich | b6e1331 | 2007-04-20 12:23:15 -0700 | [diff] [blame] | 251 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 252 | |
| 253 | /* If we are harvesting multiple skbs they will be |
| 254 | * collected on a list. |
| 255 | */ |
David S. Miller | 8728b83 | 2005-08-09 19:25:21 -0700 | [diff] [blame] | 256 | if (skb_list) |
| 257 | sctp_skb_list_tail(skb_list, queue); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 258 | else |
David S. Miller | 8728b83 | 2005-08-09 19:25:21 -0700 | [diff] [blame] | 259 | __skb_queue_tail(queue, skb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 260 | |
| 261 | /* Did we just complete partial delivery and need to get |
| 262 | * rolling again? Move pending data to the receive |
| 263 | * queue. |
| 264 | */ |
| 265 | if (clear_pd) |
| 266 | sctp_ulpq_clear_pd(ulpq); |
| 267 | |
| 268 | if (queue == &sk->sk_receive_queue) |
| 269 | sk->sk_data_ready(sk, 0); |
| 270 | return 1; |
| 271 | |
| 272 | out_free: |
David S. Miller | 8728b83 | 2005-08-09 19:25:21 -0700 | [diff] [blame] | 273 | if (skb_list) |
| 274 | sctp_queue_purge_ulpevents(skb_list); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 275 | else |
| 276 | sctp_ulpevent_free(event); |
David S. Miller | 8728b83 | 2005-08-09 19:25:21 -0700 | [diff] [blame] | 277 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 278 | return 0; |
| 279 | } |
| 280 | |
| 281 | /* 2nd Level Abstractions */ |
| 282 | |
| 283 | /* Helper function to store chunks that need to be reassembled. */ |
| 284 | static inline void sctp_ulpq_store_reasm(struct sctp_ulpq *ulpq, |
| 285 | struct sctp_ulpevent *event) |
| 286 | { |
| 287 | struct sk_buff *pos; |
| 288 | struct sctp_ulpevent *cevent; |
| 289 | __u32 tsn, ctsn; |
| 290 | |
| 291 | tsn = event->tsn; |
| 292 | |
| 293 | /* See if it belongs at the end. */ |
| 294 | pos = skb_peek_tail(&ulpq->reasm); |
| 295 | if (!pos) { |
| 296 | __skb_queue_tail(&ulpq->reasm, sctp_event2skb(event)); |
| 297 | return; |
| 298 | } |
| 299 | |
| 300 | /* Short circuit just dropping it at the end. */ |
| 301 | cevent = sctp_skb2event(pos); |
| 302 | ctsn = cevent->tsn; |
| 303 | if (TSN_lt(ctsn, tsn)) { |
| 304 | __skb_queue_tail(&ulpq->reasm, sctp_event2skb(event)); |
| 305 | return; |
| 306 | } |
| 307 | |
| 308 | /* Find the right place in this list. We store them by TSN. */ |
| 309 | skb_queue_walk(&ulpq->reasm, pos) { |
| 310 | cevent = sctp_skb2event(pos); |
| 311 | ctsn = cevent->tsn; |
| 312 | |
| 313 | if (TSN_lt(tsn, ctsn)) |
| 314 | break; |
| 315 | } |
| 316 | |
| 317 | /* Insert before pos. */ |
| 318 | __skb_insert(sctp_event2skb(event), pos->prev, pos, &ulpq->reasm); |
| 319 | |
| 320 | } |
| 321 | |
| 322 | /* Helper function to return an event corresponding to the reassembled |
| 323 | * datagram. |
| 324 | * This routine creates a re-assembled skb given the first and last skb's |
| 325 | * as stored in the reassembly queue. The skb's may be non-linear if the sctp |
| 326 | * payload was fragmented on the way and ip had to reassemble them. |
| 327 | * We add the rest of skb's to the first skb's fraglist. |
| 328 | */ |
David S. Miller | 8728b83 | 2005-08-09 19:25:21 -0700 | [diff] [blame] | 329 | static struct sctp_ulpevent *sctp_make_reassembled_event(struct sk_buff_head *queue, struct sk_buff *f_frag, struct sk_buff *l_frag) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 330 | { |
| 331 | struct sk_buff *pos; |
Vladislav Yasevich | 672e7cc | 2006-05-05 17:03:49 -0700 | [diff] [blame] | 332 | struct sk_buff *new = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 333 | struct sctp_ulpevent *event; |
| 334 | struct sk_buff *pnext, *last; |
| 335 | struct sk_buff *list = skb_shinfo(f_frag)->frag_list; |
| 336 | |
| 337 | /* Store the pointer to the 2nd skb */ |
| 338 | if (f_frag == l_frag) |
| 339 | pos = NULL; |
| 340 | else |
| 341 | pos = f_frag->next; |
| 342 | |
| 343 | /* Get the last skb in the f_frag's frag_list if present. */ |
| 344 | for (last = list; list; last = list, list = list->next); |
| 345 | |
| 346 | /* Add the list of remaining fragments to the first fragments |
| 347 | * frag_list. |
| 348 | */ |
| 349 | if (last) |
| 350 | last->next = pos; |
YOSHIFUJI Hideaki | d808ad9 | 2007-02-09 23:25:18 +0900 | [diff] [blame] | 351 | else { |
| 352 | if (skb_cloned(f_frag)) { |
| 353 | /* This is a cloned skb, we can't just modify |
| 354 | * the frag_list. We need a new skb to do that. |
| 355 | * Instead of calling skb_unshare(), we'll do it |
| 356 | * ourselves since we need to delay the free. |
| 357 | */ |
| 358 | new = skb_copy(f_frag, GFP_ATOMIC); |
| 359 | if (!new) |
| 360 | return NULL; /* try again later */ |
Vladislav Yasevich | 672e7cc | 2006-05-05 17:03:49 -0700 | [diff] [blame] | 361 | |
YOSHIFUJI Hideaki | d808ad9 | 2007-02-09 23:25:18 +0900 | [diff] [blame] | 362 | sctp_skb_set_owner_r(new, f_frag->sk); |
Vladislav Yasevich | 672e7cc | 2006-05-05 17:03:49 -0700 | [diff] [blame] | 363 | |
YOSHIFUJI Hideaki | d808ad9 | 2007-02-09 23:25:18 +0900 | [diff] [blame] | 364 | skb_shinfo(new)->frag_list = pos; |
| 365 | } else |
| 366 | skb_shinfo(f_frag)->frag_list = pos; |
| 367 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 368 | |
| 369 | /* Remove the first fragment from the reassembly queue. */ |
David S. Miller | 8728b83 | 2005-08-09 19:25:21 -0700 | [diff] [blame] | 370 | __skb_unlink(f_frag, queue); |
Vladislav Yasevich | 672e7cc | 2006-05-05 17:03:49 -0700 | [diff] [blame] | 371 | |
YOSHIFUJI Hideaki | d808ad9 | 2007-02-09 23:25:18 +0900 | [diff] [blame] | 372 | /* if we did unshare, then free the old skb and re-assign */ |
| 373 | if (new) { |
| 374 | kfree_skb(f_frag); |
| 375 | f_frag = new; |
| 376 | } |
Vladislav Yasevich | 672e7cc | 2006-05-05 17:03:49 -0700 | [diff] [blame] | 377 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 378 | while (pos) { |
| 379 | |
| 380 | pnext = pos->next; |
| 381 | |
| 382 | /* Update the len and data_len fields of the first fragment. */ |
| 383 | f_frag->len += pos->len; |
| 384 | f_frag->data_len += pos->len; |
| 385 | |
| 386 | /* Remove the fragment from the reassembly queue. */ |
David S. Miller | 8728b83 | 2005-08-09 19:25:21 -0700 | [diff] [blame] | 387 | __skb_unlink(pos, queue); |
YOSHIFUJI Hideaki | d808ad9 | 2007-02-09 23:25:18 +0900 | [diff] [blame] | 388 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 389 | /* Break if we have reached the last fragment. */ |
| 390 | if (pos == l_frag) |
| 391 | break; |
| 392 | pos->next = pnext; |
| 393 | pos = pnext; |
Stephen Hemminger | 3ff50b7 | 2007-04-20 17:09:22 -0700 | [diff] [blame] | 394 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 395 | |
| 396 | event = sctp_skb2event(f_frag); |
| 397 | SCTP_INC_STATS(SCTP_MIB_REASMUSRMSGS); |
| 398 | |
| 399 | return event; |
| 400 | } |
| 401 | |
| 402 | |
| 403 | /* Helper function to check if an incoming chunk has filled up the last |
| 404 | * missing fragment in a SCTP datagram and return the corresponding event. |
| 405 | */ |
| 406 | static inline struct sctp_ulpevent *sctp_ulpq_retrieve_reassembled(struct sctp_ulpq *ulpq) |
| 407 | { |
| 408 | struct sk_buff *pos; |
| 409 | struct sctp_ulpevent *cevent; |
| 410 | struct sk_buff *first_frag = NULL; |
| 411 | __u32 ctsn, next_tsn; |
| 412 | struct sctp_ulpevent *retval = NULL; |
Vlad Yasevich | d49d91d | 2007-03-23 11:32:00 -0700 | [diff] [blame] | 413 | struct sk_buff *pd_first = NULL; |
| 414 | struct sk_buff *pd_last = NULL; |
| 415 | size_t pd_len = 0; |
| 416 | struct sctp_association *asoc; |
| 417 | u32 pd_point; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 418 | |
| 419 | /* Initialized to 0 just to avoid compiler warning message. Will |
| 420 | * never be used with this value. It is referenced only after it |
| 421 | * is set when we find the first fragment of a message. |
| 422 | */ |
| 423 | next_tsn = 0; |
| 424 | |
| 425 | /* The chunks are held in the reasm queue sorted by TSN. |
| 426 | * Walk through the queue sequentially and look for a sequence of |
| 427 | * fragmented chunks that complete a datagram. |
| 428 | * 'first_frag' and next_tsn are reset when we find a chunk which |
| 429 | * is the first fragment of a datagram. Once these 2 fields are set |
| 430 | * we expect to find the remaining middle fragments and the last |
| 431 | * fragment in order. If not, first_frag is reset to NULL and we |
| 432 | * start the next pass when we find another first fragment. |
Vlad Yasevich | d49d91d | 2007-03-23 11:32:00 -0700 | [diff] [blame] | 433 | * |
| 434 | * There is a potential to do partial delivery if user sets |
| 435 | * SCTP_PARTIAL_DELIVERY_POINT option. Lets count some things here |
| 436 | * to see if can do PD. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 437 | */ |
| 438 | skb_queue_walk(&ulpq->reasm, pos) { |
| 439 | cevent = sctp_skb2event(pos); |
| 440 | ctsn = cevent->tsn; |
| 441 | |
| 442 | switch (cevent->msg_flags & SCTP_DATA_FRAG_MASK) { |
| 443 | case SCTP_DATA_FIRST_FRAG: |
Vlad Yasevich | d49d91d | 2007-03-23 11:32:00 -0700 | [diff] [blame] | 444 | /* If this "FIRST_FRAG" is the first |
| 445 | * element in the queue, then count it towards |
| 446 | * possible PD. |
| 447 | */ |
| 448 | if (pos == ulpq->reasm.next) { |
| 449 | pd_first = pos; |
| 450 | pd_last = pos; |
| 451 | pd_len = pos->len; |
| 452 | } else { |
| 453 | pd_first = NULL; |
| 454 | pd_last = NULL; |
| 455 | pd_len = 0; |
| 456 | } |
| 457 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 458 | first_frag = pos; |
| 459 | next_tsn = ctsn + 1; |
| 460 | break; |
| 461 | |
| 462 | case SCTP_DATA_MIDDLE_FRAG: |
Vlad Yasevich | d49d91d | 2007-03-23 11:32:00 -0700 | [diff] [blame] | 463 | if ((first_frag) && (ctsn == next_tsn)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 464 | next_tsn++; |
Vlad Yasevich | d49d91d | 2007-03-23 11:32:00 -0700 | [diff] [blame] | 465 | if (pd_first) { |
| 466 | pd_last = pos; |
| 467 | pd_len += pos->len; |
| 468 | } |
| 469 | } else |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 470 | first_frag = NULL; |
| 471 | break; |
| 472 | |
| 473 | case SCTP_DATA_LAST_FRAG: |
| 474 | if (first_frag && (ctsn == next_tsn)) |
| 475 | goto found; |
| 476 | else |
| 477 | first_frag = NULL; |
| 478 | break; |
Stephen Hemminger | 3ff50b7 | 2007-04-20 17:09:22 -0700 | [diff] [blame] | 479 | } |
Vlad Yasevich | d49d91d | 2007-03-23 11:32:00 -0700 | [diff] [blame] | 480 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 481 | |
Vlad Yasevich | d49d91d | 2007-03-23 11:32:00 -0700 | [diff] [blame] | 482 | asoc = ulpq->asoc; |
| 483 | if (pd_first) { |
| 484 | /* Make sure we can enter partial deliver. |
| 485 | * We can trigger partial delivery only if framgent |
| 486 | * interleave is set, or the socket is not already |
| 487 | * in partial delivery. |
| 488 | */ |
| 489 | if (!sctp_sk(asoc->base.sk)->frag_interleave && |
| 490 | atomic_read(&sctp_sk(asoc->base.sk)->pd_mode)) |
| 491 | goto done; |
| 492 | |
| 493 | cevent = sctp_skb2event(pd_first); |
| 494 | pd_point = sctp_sk(asoc->base.sk)->pd_point; |
| 495 | if (pd_point && pd_point <= pd_len) { |
| 496 | retval = sctp_make_reassembled_event(&ulpq->reasm, |
| 497 | pd_first, |
| 498 | pd_last); |
| 499 | if (retval) |
| 500 | sctp_ulpq_set_pd(ulpq); |
| 501 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 502 | } |
| 503 | done: |
| 504 | return retval; |
| 505 | found: |
David S. Miller | 8728b83 | 2005-08-09 19:25:21 -0700 | [diff] [blame] | 506 | retval = sctp_make_reassembled_event(&ulpq->reasm, first_frag, pos); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 507 | if (retval) |
| 508 | retval->msg_flags |= MSG_EOR; |
| 509 | goto done; |
| 510 | } |
| 511 | |
| 512 | /* Retrieve the next set of fragments of a partial message. */ |
| 513 | static inline struct sctp_ulpevent *sctp_ulpq_retrieve_partial(struct sctp_ulpq *ulpq) |
| 514 | { |
| 515 | struct sk_buff *pos, *last_frag, *first_frag; |
| 516 | struct sctp_ulpevent *cevent; |
| 517 | __u32 ctsn, next_tsn; |
| 518 | int is_last; |
| 519 | struct sctp_ulpevent *retval; |
| 520 | |
| 521 | /* The chunks are held in the reasm queue sorted by TSN. |
| 522 | * Walk through the queue sequentially and look for the first |
| 523 | * sequence of fragmented chunks. |
| 524 | */ |
| 525 | |
| 526 | if (skb_queue_empty(&ulpq->reasm)) |
| 527 | return NULL; |
| 528 | |
| 529 | last_frag = first_frag = NULL; |
| 530 | retval = NULL; |
| 531 | next_tsn = 0; |
| 532 | is_last = 0; |
| 533 | |
| 534 | skb_queue_walk(&ulpq->reasm, pos) { |
| 535 | cevent = sctp_skb2event(pos); |
| 536 | ctsn = cevent->tsn; |
| 537 | |
| 538 | switch (cevent->msg_flags & SCTP_DATA_FRAG_MASK) { |
| 539 | case SCTP_DATA_MIDDLE_FRAG: |
| 540 | if (!first_frag) { |
| 541 | first_frag = pos; |
| 542 | next_tsn = ctsn + 1; |
| 543 | last_frag = pos; |
| 544 | } else if (next_tsn == ctsn) |
| 545 | next_tsn++; |
| 546 | else |
| 547 | goto done; |
| 548 | break; |
| 549 | case SCTP_DATA_LAST_FRAG: |
| 550 | if (!first_frag) |
| 551 | first_frag = pos; |
| 552 | else if (ctsn != next_tsn) |
| 553 | goto done; |
| 554 | last_frag = pos; |
| 555 | is_last = 1; |
| 556 | goto done; |
| 557 | default: |
| 558 | return NULL; |
Stephen Hemminger | 3ff50b7 | 2007-04-20 17:09:22 -0700 | [diff] [blame] | 559 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 560 | } |
| 561 | |
| 562 | /* We have the reassembled event. There is no need to look |
| 563 | * further. |
| 564 | */ |
| 565 | done: |
David S. Miller | 8728b83 | 2005-08-09 19:25:21 -0700 | [diff] [blame] | 566 | retval = sctp_make_reassembled_event(&ulpq->reasm, first_frag, last_frag); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 567 | if (retval && is_last) |
| 568 | retval->msg_flags |= MSG_EOR; |
| 569 | |
| 570 | return retval; |
| 571 | } |
| 572 | |
| 573 | |
| 574 | /* Helper function to reassemble chunks. Hold chunks on the reasm queue that |
| 575 | * need reassembling. |
| 576 | */ |
| 577 | static struct sctp_ulpevent *sctp_ulpq_reasm(struct sctp_ulpq *ulpq, |
| 578 | struct sctp_ulpevent *event) |
| 579 | { |
| 580 | struct sctp_ulpevent *retval = NULL; |
| 581 | |
| 582 | /* Check if this is part of a fragmented message. */ |
| 583 | if (SCTP_DATA_NOT_FRAG == (event->msg_flags & SCTP_DATA_FRAG_MASK)) { |
| 584 | event->msg_flags |= MSG_EOR; |
| 585 | return event; |
| 586 | } |
| 587 | |
| 588 | sctp_ulpq_store_reasm(ulpq, event); |
| 589 | if (!ulpq->pd_mode) |
| 590 | retval = sctp_ulpq_retrieve_reassembled(ulpq); |
| 591 | else { |
| 592 | __u32 ctsn, ctsnap; |
| 593 | |
| 594 | /* Do not even bother unless this is the next tsn to |
| 595 | * be delivered. |
| 596 | */ |
| 597 | ctsn = event->tsn; |
| 598 | ctsnap = sctp_tsnmap_get_ctsn(&ulpq->asoc->peer.tsn_map); |
| 599 | if (TSN_lte(ctsn, ctsnap)) |
| 600 | retval = sctp_ulpq_retrieve_partial(ulpq); |
| 601 | } |
| 602 | |
| 603 | return retval; |
| 604 | } |
| 605 | |
| 606 | /* Retrieve the first part (sequential fragments) for partial delivery. */ |
| 607 | static inline struct sctp_ulpevent *sctp_ulpq_retrieve_first(struct sctp_ulpq *ulpq) |
| 608 | { |
| 609 | struct sk_buff *pos, *last_frag, *first_frag; |
| 610 | struct sctp_ulpevent *cevent; |
| 611 | __u32 ctsn, next_tsn; |
| 612 | struct sctp_ulpevent *retval; |
| 613 | |
| 614 | /* The chunks are held in the reasm queue sorted by TSN. |
| 615 | * Walk through the queue sequentially and look for a sequence of |
| 616 | * fragmented chunks that start a datagram. |
| 617 | */ |
| 618 | |
| 619 | if (skb_queue_empty(&ulpq->reasm)) |
| 620 | return NULL; |
| 621 | |
| 622 | last_frag = first_frag = NULL; |
| 623 | retval = NULL; |
| 624 | next_tsn = 0; |
| 625 | |
| 626 | skb_queue_walk(&ulpq->reasm, pos) { |
| 627 | cevent = sctp_skb2event(pos); |
| 628 | ctsn = cevent->tsn; |
| 629 | |
| 630 | switch (cevent->msg_flags & SCTP_DATA_FRAG_MASK) { |
| 631 | case SCTP_DATA_FIRST_FRAG: |
| 632 | if (!first_frag) { |
| 633 | first_frag = pos; |
| 634 | next_tsn = ctsn + 1; |
| 635 | last_frag = pos; |
| 636 | } else |
| 637 | goto done; |
| 638 | break; |
| 639 | |
| 640 | case SCTP_DATA_MIDDLE_FRAG: |
| 641 | if (!first_frag) |
| 642 | return NULL; |
| 643 | if (ctsn == next_tsn) { |
| 644 | next_tsn++; |
| 645 | last_frag = pos; |
| 646 | } else |
| 647 | goto done; |
| 648 | break; |
| 649 | default: |
| 650 | return NULL; |
Stephen Hemminger | 3ff50b7 | 2007-04-20 17:09:22 -0700 | [diff] [blame] | 651 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 652 | } |
| 653 | |
| 654 | /* We have the reassembled event. There is no need to look |
| 655 | * further. |
| 656 | */ |
| 657 | done: |
David S. Miller | 8728b83 | 2005-08-09 19:25:21 -0700 | [diff] [blame] | 658 | retval = sctp_make_reassembled_event(&ulpq->reasm, first_frag, last_frag); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 659 | return retval; |
| 660 | } |
| 661 | |
Vlad Yasevich | ea2dfb3 | 2007-07-13 17:01:19 -0400 | [diff] [blame^] | 662 | /* |
| 663 | * Flush out stale fragments from the reassembly queue when processing |
| 664 | * a Forward TSN. |
| 665 | * |
| 666 | * RFC 3758, Section 3.6 |
| 667 | * |
| 668 | * After receiving and processing a FORWARD TSN, the data receiver MUST |
| 669 | * take cautions in updating its re-assembly queue. The receiver MUST |
| 670 | * remove any partially reassembled message, which is still missing one |
| 671 | * or more TSNs earlier than or equal to the new cumulative TSN point. |
| 672 | * In the event that the receiver has invoked the partial delivery API, |
| 673 | * a notification SHOULD also be generated to inform the upper layer API |
| 674 | * that the message being partially delivered will NOT be completed. |
| 675 | */ |
| 676 | void sctp_ulpq_reasm_flushtsn(struct sctp_ulpq *ulpq, __u32 fwd_tsn) |
| 677 | { |
| 678 | struct sk_buff *pos, *tmp; |
| 679 | struct sctp_ulpevent *event; |
| 680 | __u32 tsn; |
| 681 | |
| 682 | if (skb_queue_empty(&ulpq->reasm)) |
| 683 | return; |
| 684 | |
| 685 | skb_queue_walk_safe(&ulpq->reasm, pos, tmp) { |
| 686 | event = sctp_skb2event(pos); |
| 687 | tsn = event->tsn; |
| 688 | |
| 689 | /* Since the entire message must be abandoned by the |
| 690 | * sender (item A3 in Section 3.5, RFC 3758), we can |
| 691 | * free all fragments on the list that are less then |
| 692 | * or equal to ctsn_point |
| 693 | */ |
| 694 | if (TSN_lte(tsn, fwd_tsn)) { |
| 695 | __skb_unlink(pos, &ulpq->reasm); |
| 696 | sctp_ulpevent_free(event); |
| 697 | } else |
| 698 | break; |
| 699 | } |
| 700 | } |
| 701 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 702 | /* Helper function to gather skbs that have possibly become |
| 703 | * ordered by an an incoming chunk. |
| 704 | */ |
| 705 | static inline void sctp_ulpq_retrieve_ordered(struct sctp_ulpq *ulpq, |
| 706 | struct sctp_ulpevent *event) |
| 707 | { |
David S. Miller | 8728b83 | 2005-08-09 19:25:21 -0700 | [diff] [blame] | 708 | struct sk_buff_head *event_list; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 709 | struct sk_buff *pos, *tmp; |
| 710 | struct sctp_ulpevent *cevent; |
| 711 | struct sctp_stream *in; |
| 712 | __u16 sid, csid; |
| 713 | __u16 ssn, cssn; |
| 714 | |
| 715 | sid = event->stream; |
| 716 | ssn = event->ssn; |
| 717 | in = &ulpq->asoc->ssnmap->in; |
| 718 | |
David S. Miller | 8728b83 | 2005-08-09 19:25:21 -0700 | [diff] [blame] | 719 | event_list = (struct sk_buff_head *) sctp_event2skb(event)->prev; |
| 720 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 721 | /* We are holding the chunks by stream, by SSN. */ |
| 722 | sctp_skb_for_each(pos, &ulpq->lobby, tmp) { |
| 723 | cevent = (struct sctp_ulpevent *) pos->cb; |
| 724 | csid = cevent->stream; |
| 725 | cssn = cevent->ssn; |
| 726 | |
| 727 | /* Have we gone too far? */ |
| 728 | if (csid > sid) |
| 729 | break; |
| 730 | |
| 731 | /* Have we not gone far enough? */ |
| 732 | if (csid < sid) |
| 733 | continue; |
| 734 | |
| 735 | if (cssn != sctp_ssn_peek(in, sid)) |
| 736 | break; |
| 737 | |
| 738 | /* Found it, so mark in the ssnmap. */ |
| 739 | sctp_ssn_next(in, sid); |
| 740 | |
David S. Miller | 8728b83 | 2005-08-09 19:25:21 -0700 | [diff] [blame] | 741 | __skb_unlink(pos, &ulpq->lobby); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 742 | |
| 743 | /* Attach all gathered skbs to the event. */ |
David S. Miller | 8728b83 | 2005-08-09 19:25:21 -0700 | [diff] [blame] | 744 | __skb_queue_tail(event_list, pos); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 745 | } |
| 746 | } |
| 747 | |
| 748 | /* Helper function to store chunks needing ordering. */ |
| 749 | static inline void sctp_ulpq_store_ordered(struct sctp_ulpq *ulpq, |
| 750 | struct sctp_ulpevent *event) |
| 751 | { |
| 752 | struct sk_buff *pos; |
| 753 | struct sctp_ulpevent *cevent; |
| 754 | __u16 sid, csid; |
| 755 | __u16 ssn, cssn; |
| 756 | |
| 757 | pos = skb_peek_tail(&ulpq->lobby); |
| 758 | if (!pos) { |
| 759 | __skb_queue_tail(&ulpq->lobby, sctp_event2skb(event)); |
| 760 | return; |
| 761 | } |
| 762 | |
| 763 | sid = event->stream; |
| 764 | ssn = event->ssn; |
YOSHIFUJI Hideaki | d808ad9 | 2007-02-09 23:25:18 +0900 | [diff] [blame] | 765 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 766 | cevent = (struct sctp_ulpevent *) pos->cb; |
| 767 | csid = cevent->stream; |
| 768 | cssn = cevent->ssn; |
| 769 | if (sid > csid) { |
| 770 | __skb_queue_tail(&ulpq->lobby, sctp_event2skb(event)); |
| 771 | return; |
| 772 | } |
| 773 | |
| 774 | if ((sid == csid) && SSN_lt(cssn, ssn)) { |
| 775 | __skb_queue_tail(&ulpq->lobby, sctp_event2skb(event)); |
| 776 | return; |
| 777 | } |
| 778 | |
| 779 | /* Find the right place in this list. We store them by |
| 780 | * stream ID and then by SSN. |
| 781 | */ |
| 782 | skb_queue_walk(&ulpq->lobby, pos) { |
| 783 | cevent = (struct sctp_ulpevent *) pos->cb; |
| 784 | csid = cevent->stream; |
| 785 | cssn = cevent->ssn; |
| 786 | |
| 787 | if (csid > sid) |
| 788 | break; |
| 789 | if (csid == sid && SSN_lt(ssn, cssn)) |
| 790 | break; |
| 791 | } |
| 792 | |
| 793 | |
| 794 | /* Insert before pos. */ |
| 795 | __skb_insert(sctp_event2skb(event), pos->prev, pos, &ulpq->lobby); |
| 796 | |
| 797 | } |
| 798 | |
| 799 | static struct sctp_ulpevent *sctp_ulpq_order(struct sctp_ulpq *ulpq, |
David S. Miller | 8728b83 | 2005-08-09 19:25:21 -0700 | [diff] [blame] | 800 | struct sctp_ulpevent *event) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 801 | { |
| 802 | __u16 sid, ssn; |
| 803 | struct sctp_stream *in; |
| 804 | |
| 805 | /* Check if this message needs ordering. */ |
| 806 | if (SCTP_DATA_UNORDERED & event->msg_flags) |
| 807 | return event; |
| 808 | |
| 809 | /* Note: The stream ID must be verified before this routine. */ |
| 810 | sid = event->stream; |
| 811 | ssn = event->ssn; |
| 812 | in = &ulpq->asoc->ssnmap->in; |
| 813 | |
| 814 | /* Is this the expected SSN for this stream ID? */ |
| 815 | if (ssn != sctp_ssn_peek(in, sid)) { |
| 816 | /* We've received something out of order, so find where it |
| 817 | * needs to be placed. We order by stream and then by SSN. |
| 818 | */ |
| 819 | sctp_ulpq_store_ordered(ulpq, event); |
| 820 | return NULL; |
| 821 | } |
| 822 | |
| 823 | /* Mark that the next chunk has been found. */ |
| 824 | sctp_ssn_next(in, sid); |
| 825 | |
| 826 | /* Go find any other chunks that were waiting for |
| 827 | * ordering. |
| 828 | */ |
| 829 | sctp_ulpq_retrieve_ordered(ulpq, event); |
| 830 | |
| 831 | return event; |
| 832 | } |
| 833 | |
| 834 | /* Helper function to gather skbs that have possibly become |
| 835 | * ordered by forward tsn skipping their dependencies. |
| 836 | */ |
Vlad Yasevich | ea2dfb3 | 2007-07-13 17:01:19 -0400 | [diff] [blame^] | 837 | static inline void sctp_ulpq_reap_ordered(struct sctp_ulpq *ulpq, __u16 sid) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 838 | { |
| 839 | struct sk_buff *pos, *tmp; |
| 840 | struct sctp_ulpevent *cevent; |
David S. Miller | 8728b83 | 2005-08-09 19:25:21 -0700 | [diff] [blame] | 841 | struct sctp_ulpevent *event; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 842 | struct sctp_stream *in; |
| 843 | struct sk_buff_head temp; |
| 844 | __u16 csid, cssn; |
| 845 | |
| 846 | in = &ulpq->asoc->ssnmap->in; |
| 847 | |
| 848 | /* We are holding the chunks by stream, by SSN. */ |
David S. Miller | 8728b83 | 2005-08-09 19:25:21 -0700 | [diff] [blame] | 849 | skb_queue_head_init(&temp); |
| 850 | event = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 851 | sctp_skb_for_each(pos, &ulpq->lobby, tmp) { |
| 852 | cevent = (struct sctp_ulpevent *) pos->cb; |
| 853 | csid = cevent->stream; |
| 854 | cssn = cevent->ssn; |
| 855 | |
Vlad Yasevich | ea2dfb3 | 2007-07-13 17:01:19 -0400 | [diff] [blame^] | 856 | /* Have we gone too far? */ |
| 857 | if (csid > sid) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 858 | break; |
| 859 | |
Vlad Yasevich | ea2dfb3 | 2007-07-13 17:01:19 -0400 | [diff] [blame^] | 860 | /* Have we not gone far enough? */ |
| 861 | if (csid < sid) |
| 862 | continue; |
| 863 | |
| 864 | /* see if this ssn has been marked by skipping */ |
| 865 | if (!SSN_lt(cssn, sctp_ssn_peek(in, csid))) |
| 866 | break; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 867 | |
David S. Miller | 8728b83 | 2005-08-09 19:25:21 -0700 | [diff] [blame] | 868 | __skb_unlink(pos, &ulpq->lobby); |
Vlad Yasevich | ea2dfb3 | 2007-07-13 17:01:19 -0400 | [diff] [blame^] | 869 | if (!event) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 870 | /* Create a temporary list to collect chunks on. */ |
| 871 | event = sctp_skb2event(pos); |
Vlad Yasevich | ea2dfb3 | 2007-07-13 17:01:19 -0400 | [diff] [blame^] | 872 | |
| 873 | /* Attach all gathered skbs to the event. */ |
| 874 | __skb_queue_tail(&temp, pos); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 875 | } |
| 876 | |
David S. Miller | 8728b83 | 2005-08-09 19:25:21 -0700 | [diff] [blame] | 877 | /* Send event to the ULP. 'event' is the sctp_ulpevent for |
| 878 | * very first SKB on the 'temp' list. |
| 879 | */ |
Vlad Yasevich | ea2dfb3 | 2007-07-13 17:01:19 -0400 | [diff] [blame^] | 880 | if (event) { |
| 881 | /* see if we have more ordered that we can deliver */ |
| 882 | sctp_ulpq_retrieve_ordered(ulpq, event); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 883 | sctp_ulpq_tail_event(ulpq, event); |
Vlad Yasevich | ea2dfb3 | 2007-07-13 17:01:19 -0400 | [diff] [blame^] | 884 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 885 | } |
| 886 | |
Vlad Yasevich | ea2dfb3 | 2007-07-13 17:01:19 -0400 | [diff] [blame^] | 887 | /* Skip over an SSN. This is used during the processing of |
| 888 | * Forwared TSN chunk to skip over the abandoned ordered data |
| 889 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 890 | void sctp_ulpq_skip(struct sctp_ulpq *ulpq, __u16 sid, __u16 ssn) |
| 891 | { |
| 892 | struct sctp_stream *in; |
| 893 | |
| 894 | /* Note: The stream ID must be verified before this routine. */ |
| 895 | in = &ulpq->asoc->ssnmap->in; |
| 896 | |
| 897 | /* Is this an old SSN? If so ignore. */ |
| 898 | if (SSN_lt(ssn, sctp_ssn_peek(in, sid))) |
| 899 | return; |
| 900 | |
| 901 | /* Mark that we are no longer expecting this SSN or lower. */ |
| 902 | sctp_ssn_skip(in, sid, ssn); |
| 903 | |
| 904 | /* Go find any other chunks that were waiting for |
YOSHIFUJI Hideaki | d808ad9 | 2007-02-09 23:25:18 +0900 | [diff] [blame] | 905 | * ordering and deliver them if needed. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 906 | */ |
Vlad Yasevich | ea2dfb3 | 2007-07-13 17:01:19 -0400 | [diff] [blame^] | 907 | sctp_ulpq_reap_ordered(ulpq, sid); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 908 | return; |
| 909 | } |
| 910 | |
| 911 | /* Renege 'needed' bytes from the ordering queue. */ |
| 912 | static __u16 sctp_ulpq_renege_order(struct sctp_ulpq *ulpq, __u16 needed) |
| 913 | { |
| 914 | __u16 freed = 0; |
| 915 | __u32 tsn; |
| 916 | struct sk_buff *skb; |
| 917 | struct sctp_ulpevent *event; |
| 918 | struct sctp_tsnmap *tsnmap; |
| 919 | |
| 920 | tsnmap = &ulpq->asoc->peer.tsn_map; |
| 921 | |
| 922 | while ((skb = __skb_dequeue_tail(&ulpq->lobby)) != NULL) { |
| 923 | freed += skb_headlen(skb); |
| 924 | event = sctp_skb2event(skb); |
| 925 | tsn = event->tsn; |
| 926 | |
| 927 | sctp_ulpevent_free(event); |
| 928 | sctp_tsnmap_renege(tsnmap, tsn); |
| 929 | if (freed >= needed) |
| 930 | return freed; |
| 931 | } |
| 932 | |
| 933 | return freed; |
| 934 | } |
| 935 | |
| 936 | /* Renege 'needed' bytes from the reassembly queue. */ |
| 937 | static __u16 sctp_ulpq_renege_frags(struct sctp_ulpq *ulpq, __u16 needed) |
| 938 | { |
| 939 | __u16 freed = 0; |
| 940 | __u32 tsn; |
| 941 | struct sk_buff *skb; |
| 942 | struct sctp_ulpevent *event; |
| 943 | struct sctp_tsnmap *tsnmap; |
| 944 | |
| 945 | tsnmap = &ulpq->asoc->peer.tsn_map; |
| 946 | |
| 947 | /* Walk backwards through the list, reneges the newest tsns. */ |
| 948 | while ((skb = __skb_dequeue_tail(&ulpq->reasm)) != NULL) { |
| 949 | freed += skb_headlen(skb); |
| 950 | event = sctp_skb2event(skb); |
| 951 | tsn = event->tsn; |
| 952 | |
| 953 | sctp_ulpevent_free(event); |
| 954 | sctp_tsnmap_renege(tsnmap, tsn); |
| 955 | if (freed >= needed) |
| 956 | return freed; |
| 957 | } |
| 958 | |
| 959 | return freed; |
| 960 | } |
| 961 | |
| 962 | /* Partial deliver the first message as there is pressure on rwnd. */ |
| 963 | void sctp_ulpq_partial_delivery(struct sctp_ulpq *ulpq, |
Alexey Dobriyan | 3182cd84 | 2005-07-11 20:57:47 -0700 | [diff] [blame] | 964 | struct sctp_chunk *chunk, |
Al Viro | dd0fc66 | 2005-10-07 07:46:04 +0100 | [diff] [blame] | 965 | gfp_t gfp) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 966 | { |
| 967 | struct sctp_ulpevent *event; |
| 968 | struct sctp_association *asoc; |
Vlad Yasevich | b6e1331 | 2007-04-20 12:23:15 -0700 | [diff] [blame] | 969 | struct sctp_sock *sp; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 970 | |
| 971 | asoc = ulpq->asoc; |
Vlad Yasevich | b6e1331 | 2007-04-20 12:23:15 -0700 | [diff] [blame] | 972 | sp = sctp_sk(asoc->base.sk); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 973 | |
Vlad Yasevich | b6e1331 | 2007-04-20 12:23:15 -0700 | [diff] [blame] | 974 | /* If the association is already in Partial Delivery mode |
| 975 | * we have noting to do. |
| 976 | */ |
| 977 | if (ulpq->pd_mode) |
| 978 | return; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 979 | |
Vlad Yasevich | b6e1331 | 2007-04-20 12:23:15 -0700 | [diff] [blame] | 980 | /* If the user enabled fragment interleave socket option, |
| 981 | * multiple associations can enter partial delivery. |
| 982 | * Otherwise, we can only enter partial delivery if the |
| 983 | * socket is not in partial deliver mode. |
| 984 | */ |
| 985 | if (sp->frag_interleave || atomic_read(&sp->pd_mode) == 0) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 986 | /* Is partial delivery possible? */ |
| 987 | event = sctp_ulpq_retrieve_first(ulpq); |
| 988 | /* Send event to the ULP. */ |
| 989 | if (event) { |
| 990 | sctp_ulpq_tail_event(ulpq, event); |
Vlad Yasevich | d49d91d | 2007-03-23 11:32:00 -0700 | [diff] [blame] | 991 | sctp_ulpq_set_pd(ulpq); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 992 | return; |
| 993 | } |
| 994 | } |
| 995 | } |
| 996 | |
| 997 | /* Renege some packets to make room for an incoming chunk. */ |
| 998 | void sctp_ulpq_renege(struct sctp_ulpq *ulpq, struct sctp_chunk *chunk, |
Al Viro | dd0fc66 | 2005-10-07 07:46:04 +0100 | [diff] [blame] | 999 | gfp_t gfp) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1000 | { |
| 1001 | struct sctp_association *asoc; |
| 1002 | __u16 needed, freed; |
| 1003 | |
| 1004 | asoc = ulpq->asoc; |
| 1005 | |
| 1006 | if (chunk) { |
| 1007 | needed = ntohs(chunk->chunk_hdr->length); |
| 1008 | needed -= sizeof(sctp_data_chunk_t); |
YOSHIFUJI Hideaki | d808ad9 | 2007-02-09 23:25:18 +0900 | [diff] [blame] | 1009 | } else |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1010 | needed = SCTP_DEFAULT_MAXWINDOW; |
| 1011 | |
| 1012 | freed = 0; |
| 1013 | |
| 1014 | if (skb_queue_empty(&asoc->base.sk->sk_receive_queue)) { |
| 1015 | freed = sctp_ulpq_renege_order(ulpq, needed); |
| 1016 | if (freed < needed) { |
| 1017 | freed += sctp_ulpq_renege_frags(ulpq, needed - freed); |
| 1018 | } |
| 1019 | } |
| 1020 | /* If able to free enough room, accept this chunk. */ |
| 1021 | if (chunk && (freed >= needed)) { |
| 1022 | __u32 tsn; |
| 1023 | tsn = ntohl(chunk->subh.data_hdr->tsn); |
| 1024 | sctp_tsnmap_mark(&asoc->peer.tsn_map, tsn); |
| 1025 | sctp_ulpq_tail_data(ulpq, chunk, gfp); |
YOSHIFUJI Hideaki | d808ad9 | 2007-02-09 23:25:18 +0900 | [diff] [blame] | 1026 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1027 | sctp_ulpq_partial_delivery(ulpq, chunk, gfp); |
| 1028 | } |
| 1029 | |
| 1030 | return; |
| 1031 | } |
| 1032 | |
| 1033 | |
| 1034 | |
| 1035 | /* Notify the application if an association is aborted and in |
| 1036 | * partial delivery mode. Send up any pending received messages. |
| 1037 | */ |
Al Viro | dd0fc66 | 2005-10-07 07:46:04 +0100 | [diff] [blame] | 1038 | void sctp_ulpq_abort_pd(struct sctp_ulpq *ulpq, gfp_t gfp) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1039 | { |
| 1040 | struct sctp_ulpevent *ev = NULL; |
| 1041 | struct sock *sk; |
| 1042 | |
| 1043 | if (!ulpq->pd_mode) |
| 1044 | return; |
| 1045 | |
| 1046 | sk = ulpq->asoc->base.sk; |
| 1047 | if (sctp_ulpevent_type_enabled(SCTP_PARTIAL_DELIVERY_EVENT, |
| 1048 | &sctp_sk(sk)->subscribe)) |
| 1049 | ev = sctp_ulpevent_make_pdapi(ulpq->asoc, |
| 1050 | SCTP_PARTIAL_DELIVERY_ABORTED, |
| 1051 | gfp); |
| 1052 | if (ev) |
| 1053 | __skb_queue_tail(&sk->sk_receive_queue, sctp_event2skb(ev)); |
| 1054 | |
| 1055 | /* If there is data waiting, send it up the socket now. */ |
| 1056 | if (sctp_ulpq_clear_pd(ulpq) || ev) |
| 1057 | sk->sk_data_ready(sk, 0); |
| 1058 | } |