1 /* 2 * net/tipc/msg.c: TIPC message header routines 3 * 4 * Copyright (c) 2000-2006, 2014-2015, Ericsson AB 5 * Copyright (c) 2005, 2010-2011, Wind River Systems 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions are met: 10 * 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the names of the copyright holders nor the names of its 17 * contributors may be used to endorse or promote products derived from 18 * this software without specific prior written permission. 19 * 20 * Alternatively, this software may be distributed under the terms of the 21 * GNU General Public License ("GPL") version 2 as published by the Free 22 * Software Foundation. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 25 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE 28 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 29 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 30 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 31 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 32 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 33 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 34 * POSSIBILITY OF SUCH DAMAGE. 35 */ 36 37 #include <net/sock.h> 38 #include "core.h" 39 #include "msg.h" 40 #include "addr.h" 41 #include "name_table.h" 42 43 #define MAX_FORWARD_SIZE 1024 44 #define BUF_HEADROOM (LL_MAX_HEADER + 48) 45 #define BUF_TAILROOM 16 46 47 static unsigned int align(unsigned int i) 48 { 49 return (i + 3) & ~3u; 50 } 51 52 /** 53 * tipc_buf_acquire - creates a TIPC message buffer 54 * @size: message size (including TIPC header) 55 * 56 * Returns a new buffer with data pointers set to the specified size. 57 * 58 * NOTE: Headroom is reserved to allow prepending of a data link header. 59 * There may also be unrequested tailroom present at the buffer's end. 60 */ 61 struct sk_buff *tipc_buf_acquire(u32 size, gfp_t gfp) 62 { 63 struct sk_buff *skb; 64 unsigned int buf_size = (BUF_HEADROOM + size + 3) & ~3u; 65 66 skb = alloc_skb_fclone(buf_size, gfp); 67 if (skb) { 68 skb_reserve(skb, BUF_HEADROOM); 69 skb_put(skb, size); 70 skb->next = NULL; 71 } 72 return skb; 73 } 74 75 void tipc_msg_init(u32 own_node, struct tipc_msg *m, u32 user, u32 type, 76 u32 hsize, u32 dnode) 77 { 78 memset(m, 0, hsize); 79 msg_set_version(m); 80 msg_set_user(m, user); 81 msg_set_hdr_sz(m, hsize); 82 msg_set_size(m, hsize); 83 msg_set_prevnode(m, own_node); 84 msg_set_type(m, type); 85 if (hsize > SHORT_H_SIZE) { 86 msg_set_orignode(m, own_node); 87 msg_set_destnode(m, dnode); 88 } 89 } 90 91 struct sk_buff *tipc_msg_create(uint user, uint type, 92 uint hdr_sz, uint data_sz, u32 dnode, 93 u32 onode, u32 dport, u32 oport, int errcode) 94 { 95 struct tipc_msg *msg; 96 struct sk_buff *buf; 97 98 buf = tipc_buf_acquire(hdr_sz + data_sz, GFP_ATOMIC); 99 if (unlikely(!buf)) 100 return NULL; 101 102 msg = buf_msg(buf); 103 tipc_msg_init(onode, msg, user, type, hdr_sz, dnode); 104 msg_set_size(msg, hdr_sz + data_sz); 105 msg_set_origport(msg, oport); 106 msg_set_destport(msg, dport); 107 msg_set_errcode(msg, errcode); 108 if (hdr_sz > SHORT_H_SIZE) { 109 msg_set_orignode(msg, onode); 110 msg_set_destnode(msg, dnode); 111 } 112 return buf; 113 } 114 115 /* tipc_buf_append(): Append a buffer to the fragment list of another buffer 116 * @*headbuf: in: NULL for first frag, otherwise value returned from prev call 117 * out: set when successful non-complete reassembly, otherwise NULL 118 * @*buf: in: the buffer to append. Always defined 119 * out: head buf after successful complete reassembly, otherwise NULL 120 * Returns 1 when reassembly complete, otherwise 0 121 */ 122 int tipc_buf_append(struct sk_buff **headbuf, struct sk_buff **buf) 123 { 124 struct sk_buff *head = *headbuf; 125 struct sk_buff *frag = *buf; 126 struct sk_buff *tail = NULL; 127 struct tipc_msg *msg; 128 u32 fragid; 129 int delta; 130 bool headstolen; 131 132 if (!frag) 133 goto err; 134 135 msg = buf_msg(frag); 136 fragid = msg_type(msg); 137 frag->next = NULL; 138 skb_pull(frag, msg_hdr_sz(msg)); 139 140 if (fragid == FIRST_FRAGMENT) { 141 if (unlikely(head)) 142 goto err; 143 if (unlikely(skb_unclone(frag, GFP_ATOMIC))) 144 goto err; 145 head = *headbuf = frag; 146 *buf = NULL; 147 TIPC_SKB_CB(head)->tail = NULL; 148 if (skb_is_nonlinear(head)) { 149 skb_walk_frags(head, tail) { 150 TIPC_SKB_CB(head)->tail = tail; 151 } 152 } else { 153 skb_frag_list_init(head); 154 } 155 return 0; 156 } 157 158 if (!head) 159 goto err; 160 161 if (skb_try_coalesce(head, frag, &headstolen, &delta)) { 162 kfree_skb_partial(frag, headstolen); 163 } else { 164 tail = TIPC_SKB_CB(head)->tail; 165 if (!skb_has_frag_list(head)) 166 skb_shinfo(head)->frag_list = frag; 167 else 168 tail->next = frag; 169 head->truesize += frag->truesize; 170 head->data_len += frag->len; 171 head->len += frag->len; 172 TIPC_SKB_CB(head)->tail = frag; 173 } 174 175 if (fragid == LAST_FRAGMENT) { 176 TIPC_SKB_CB(head)->validated = false; 177 if (unlikely(!tipc_msg_validate(&head))) 178 goto err; 179 *buf = head; 180 TIPC_SKB_CB(head)->tail = NULL; 181 *headbuf = NULL; 182 return 1; 183 } 184 *buf = NULL; 185 return 0; 186 err: 187 kfree_skb(*buf); 188 kfree_skb(*headbuf); 189 *buf = *headbuf = NULL; 190 return 0; 191 } 192 193 /* tipc_msg_validate - validate basic format of received message 194 * 195 * This routine ensures a TIPC message has an acceptable header, and at least 196 * as much data as the header indicates it should. The routine also ensures 197 * that the entire message header is stored in the main fragment of the message 198 * buffer, to simplify future access to message header fields. 199 * 200 * Note: Having extra info present in the message header or data areas is OK. 201 * TIPC will ignore the excess, under the assumption that it is optional info 202 * introduced by a later release of the protocol. 203 */ 204 bool tipc_msg_validate(struct sk_buff **_skb) 205 { 206 struct sk_buff *skb = *_skb; 207 struct tipc_msg *hdr; 208 int msz, hsz; 209 210 /* Ensure that flow control ratio condition is satisfied */ 211 if (unlikely(skb->truesize / buf_roundup_len(skb) >= 4)) { 212 skb = skb_copy_expand(skb, BUF_HEADROOM, 0, GFP_ATOMIC); 213 if (!skb) 214 return false; 215 kfree_skb(*_skb); 216 *_skb = skb; 217 } 218 219 if (unlikely(TIPC_SKB_CB(skb)->validated)) 220 return true; 221 if (unlikely(!pskb_may_pull(skb, MIN_H_SIZE))) 222 return false; 223 224 hsz = msg_hdr_sz(buf_msg(skb)); 225 if (unlikely(hsz < MIN_H_SIZE) || (hsz > MAX_H_SIZE)) 226 return false; 227 if (unlikely(!pskb_may_pull(skb, hsz))) 228 return false; 229 230 hdr = buf_msg(skb); 231 if (unlikely(msg_version(hdr) != TIPC_VERSION)) 232 return false; 233 234 msz = msg_size(hdr); 235 if (unlikely(msz < hsz)) 236 return false; 237 if (unlikely((msz - hsz) > TIPC_MAX_USER_MSG_SIZE)) 238 return false; 239 if (unlikely(skb->len < msz)) 240 return false; 241 242 TIPC_SKB_CB(skb)->validated = true; 243 return true; 244 } 245 246 /** 247 * tipc_msg_build - create buffer chain containing specified header and data 248 * @mhdr: Message header, to be prepended to data 249 * @m: User message 250 * @dsz: Total length of user data 251 * @pktmax: Max packet size that can be used 252 * @list: Buffer or chain of buffers to be returned to caller 253 * 254 * Note that the recursive call we are making here is safe, since it can 255 * logically go only one further level down. 256 * 257 * Returns message data size or errno: -ENOMEM, -EFAULT 258 */ 259 int tipc_msg_build(struct tipc_msg *mhdr, struct msghdr *m, int offset, 260 int dsz, int pktmax, struct sk_buff_head *list) 261 { 262 int mhsz = msg_hdr_sz(mhdr); 263 struct tipc_msg pkthdr; 264 int msz = mhsz + dsz; 265 int pktrem = pktmax; 266 struct sk_buff *skb; 267 int drem = dsz; 268 int pktno = 1; 269 char *pktpos; 270 int pktsz; 271 int rc; 272 273 msg_set_size(mhdr, msz); 274 275 /* No fragmentation needed? */ 276 if (likely(msz <= pktmax)) { 277 skb = tipc_buf_acquire(msz, GFP_KERNEL); 278 279 /* Fall back to smaller MTU if node local message */ 280 if (unlikely(!skb)) { 281 if (pktmax != MAX_MSG_SIZE) 282 return -ENOMEM; 283 rc = tipc_msg_build(mhdr, m, offset, dsz, FB_MTU, list); 284 if (rc != dsz) 285 return rc; 286 if (tipc_msg_assemble(list)) 287 return dsz; 288 return -ENOMEM; 289 } 290 skb_orphan(skb); 291 __skb_queue_tail(list, skb); 292 skb_copy_to_linear_data(skb, mhdr, mhsz); 293 pktpos = skb->data + mhsz; 294 if (copy_from_iter_full(pktpos, dsz, &m->msg_iter)) 295 return dsz; 296 rc = -EFAULT; 297 goto error; 298 } 299 300 /* Prepare reusable fragment header */ 301 tipc_msg_init(msg_prevnode(mhdr), &pkthdr, MSG_FRAGMENTER, 302 FIRST_FRAGMENT, INT_H_SIZE, msg_destnode(mhdr)); 303 msg_set_size(&pkthdr, pktmax); 304 msg_set_fragm_no(&pkthdr, pktno); 305 msg_set_importance(&pkthdr, msg_importance(mhdr)); 306 307 /* Prepare first fragment */ 308 skb = tipc_buf_acquire(pktmax, GFP_KERNEL); 309 if (!skb) 310 return -ENOMEM; 311 skb_orphan(skb); 312 __skb_queue_tail(list, skb); 313 pktpos = skb->data; 314 skb_copy_to_linear_data(skb, &pkthdr, INT_H_SIZE); 315 pktpos += INT_H_SIZE; 316 pktrem -= INT_H_SIZE; 317 skb_copy_to_linear_data_offset(skb, INT_H_SIZE, mhdr, mhsz); 318 pktpos += mhsz; 319 pktrem -= mhsz; 320 321 do { 322 if (drem < pktrem) 323 pktrem = drem; 324 325 if (!copy_from_iter_full(pktpos, pktrem, &m->msg_iter)) { 326 rc = -EFAULT; 327 goto error; 328 } 329 drem -= pktrem; 330 331 if (!drem) 332 break; 333 334 /* Prepare new fragment: */ 335 if (drem < (pktmax - INT_H_SIZE)) 336 pktsz = drem + INT_H_SIZE; 337 else 338 pktsz = pktmax; 339 skb = tipc_buf_acquire(pktsz, GFP_KERNEL); 340 if (!skb) { 341 rc = -ENOMEM; 342 goto error; 343 } 344 skb_orphan(skb); 345 __skb_queue_tail(list, skb); 346 msg_set_type(&pkthdr, FRAGMENT); 347 msg_set_size(&pkthdr, pktsz); 348 msg_set_fragm_no(&pkthdr, ++pktno); 349 skb_copy_to_linear_data(skb, &pkthdr, INT_H_SIZE); 350 pktpos = skb->data + INT_H_SIZE; 351 pktrem = pktsz - INT_H_SIZE; 352 353 } while (1); 354 msg_set_type(buf_msg(skb), LAST_FRAGMENT); 355 return dsz; 356 error: 357 __skb_queue_purge(list); 358 __skb_queue_head_init(list); 359 return rc; 360 } 361 362 /** 363 * tipc_msg_bundle(): Append contents of a buffer to tail of an existing one 364 * @skb: the buffer to append to ("bundle") 365 * @msg: message to be appended 366 * @mtu: max allowable size for the bundle buffer 367 * Consumes buffer if successful 368 * Returns true if bundling could be performed, otherwise false 369 */ 370 bool tipc_msg_bundle(struct sk_buff *skb, struct tipc_msg *msg, u32 mtu) 371 { 372 struct tipc_msg *bmsg; 373 unsigned int bsz; 374 unsigned int msz = msg_size(msg); 375 u32 start, pad; 376 u32 max = mtu - INT_H_SIZE; 377 378 if (likely(msg_user(msg) == MSG_FRAGMENTER)) 379 return false; 380 if (!skb) 381 return false; 382 bmsg = buf_msg(skb); 383 bsz = msg_size(bmsg); 384 start = align(bsz); 385 pad = start - bsz; 386 387 if (unlikely(msg_user(msg) == TUNNEL_PROTOCOL)) 388 return false; 389 if (unlikely(msg_user(msg) == BCAST_PROTOCOL)) 390 return false; 391 if (unlikely(msg_user(bmsg) != MSG_BUNDLER)) 392 return false; 393 if (unlikely(skb_tailroom(skb) < (pad + msz))) 394 return false; 395 if (unlikely(max < (start + msz))) 396 return false; 397 if ((msg_importance(msg) < TIPC_SYSTEM_IMPORTANCE) && 398 (msg_importance(bmsg) == TIPC_SYSTEM_IMPORTANCE)) 399 return false; 400 401 skb_put(skb, pad + msz); 402 skb_copy_to_linear_data_offset(skb, start, msg, msz); 403 msg_set_size(bmsg, start + msz); 404 msg_set_msgcnt(bmsg, msg_msgcnt(bmsg) + 1); 405 return true; 406 } 407 408 /** 409 * tipc_msg_extract(): extract bundled inner packet from buffer 410 * @skb: buffer to be extracted from. 411 * @iskb: extracted inner buffer, to be returned 412 * @pos: position in outer message of msg to be extracted. 413 * Returns position of next msg 414 * Consumes outer buffer when last packet extracted 415 * Returns true when when there is an extracted buffer, otherwise false 416 */ 417 bool tipc_msg_extract(struct sk_buff *skb, struct sk_buff **iskb, int *pos) 418 { 419 struct tipc_msg *hdr, *ihdr; 420 int imsz; 421 422 *iskb = NULL; 423 if (unlikely(skb_linearize(skb))) 424 goto none; 425 426 hdr = buf_msg(skb); 427 if (unlikely(*pos > (msg_data_sz(hdr) - MIN_H_SIZE))) 428 goto none; 429 430 ihdr = (struct tipc_msg *)(msg_data(hdr) + *pos); 431 imsz = msg_size(ihdr); 432 433 if ((*pos + imsz) > msg_data_sz(hdr)) 434 goto none; 435 436 *iskb = tipc_buf_acquire(imsz, GFP_ATOMIC); 437 if (!*iskb) 438 goto none; 439 440 skb_copy_to_linear_data(*iskb, ihdr, imsz); 441 if (unlikely(!tipc_msg_validate(iskb))) 442 goto none; 443 444 *pos += align(imsz); 445 return true; 446 none: 447 kfree_skb(skb); 448 kfree_skb(*iskb); 449 *iskb = NULL; 450 return false; 451 } 452 453 /** 454 * tipc_msg_make_bundle(): Create bundle buf and append message to its tail 455 * @list: the buffer chain, where head is the buffer to replace/append 456 * @skb: buffer to be created, appended to and returned in case of success 457 * @msg: message to be appended 458 * @mtu: max allowable size for the bundle buffer, inclusive header 459 * @dnode: destination node for message. (Not always present in header) 460 * Returns true if success, otherwise false 461 */ 462 bool tipc_msg_make_bundle(struct sk_buff **skb, struct tipc_msg *msg, 463 u32 mtu, u32 dnode) 464 { 465 struct sk_buff *_skb; 466 struct tipc_msg *bmsg; 467 u32 msz = msg_size(msg); 468 u32 max = mtu - INT_H_SIZE; 469 470 if (msg_user(msg) == MSG_FRAGMENTER) 471 return false; 472 if (msg_user(msg) == TUNNEL_PROTOCOL) 473 return false; 474 if (msg_user(msg) == BCAST_PROTOCOL) 475 return false; 476 if (msz > (max / 2)) 477 return false; 478 479 _skb = tipc_buf_acquire(max, GFP_ATOMIC); 480 if (!_skb) 481 return false; 482 483 skb_trim(_skb, INT_H_SIZE); 484 bmsg = buf_msg(_skb); 485 tipc_msg_init(msg_prevnode(msg), bmsg, MSG_BUNDLER, 0, 486 INT_H_SIZE, dnode); 487 if (msg_isdata(msg)) 488 msg_set_importance(bmsg, TIPC_CRITICAL_IMPORTANCE); 489 else 490 msg_set_importance(bmsg, TIPC_SYSTEM_IMPORTANCE); 491 msg_set_seqno(bmsg, msg_seqno(msg)); 492 msg_set_ack(bmsg, msg_ack(msg)); 493 msg_set_bcast_ack(bmsg, msg_bcast_ack(msg)); 494 tipc_msg_bundle(_skb, msg, mtu); 495 *skb = _skb; 496 return true; 497 } 498 499 /** 500 * tipc_msg_reverse(): swap source and destination addresses and add error code 501 * @own_node: originating node id for reversed message 502 * @skb: buffer containing message to be reversed; will be consumed 503 * @err: error code to be set in message, if any 504 * Replaces consumed buffer with new one when successful 505 * Returns true if success, otherwise false 506 */ 507 bool tipc_msg_reverse(u32 own_node, struct sk_buff **skb, int err) 508 { 509 struct sk_buff *_skb = *skb; 510 struct tipc_msg *_hdr, *hdr; 511 int hlen, dlen; 512 513 if (skb_linearize(_skb)) 514 goto exit; 515 _hdr = buf_msg(_skb); 516 dlen = min_t(uint, msg_data_sz(_hdr), MAX_FORWARD_SIZE); 517 hlen = msg_hdr_sz(_hdr); 518 519 if (msg_dest_droppable(_hdr)) 520 goto exit; 521 if (msg_errcode(_hdr)) 522 goto exit; 523 524 /* Never return SHORT header */ 525 if (hlen == SHORT_H_SIZE) 526 hlen = BASIC_H_SIZE; 527 528 /* Don't return data along with SYN+, - sender has a clone */ 529 if (msg_is_syn(_hdr) && err == TIPC_ERR_OVERLOAD) 530 dlen = 0; 531 532 /* Allocate new buffer to return */ 533 *skb = tipc_buf_acquire(hlen + dlen, GFP_ATOMIC); 534 if (!*skb) 535 goto exit; 536 memcpy((*skb)->data, _skb->data, msg_hdr_sz(_hdr)); 537 memcpy((*skb)->data + hlen, msg_data(_hdr), dlen); 538 539 /* Build reverse header in new buffer */ 540 hdr = buf_msg(*skb); 541 msg_set_hdr_sz(hdr, hlen); 542 msg_set_errcode(hdr, err); 543 msg_set_non_seq(hdr, 0); 544 msg_set_origport(hdr, msg_destport(_hdr)); 545 msg_set_destport(hdr, msg_origport(_hdr)); 546 msg_set_destnode(hdr, msg_prevnode(_hdr)); 547 msg_set_prevnode(hdr, own_node); 548 msg_set_orignode(hdr, own_node); 549 msg_set_size(hdr, hlen + dlen); 550 skb_orphan(_skb); 551 kfree_skb(_skb); 552 return true; 553 exit: 554 kfree_skb(_skb); 555 *skb = NULL; 556 return false; 557 } 558 559 bool tipc_msg_skb_clone(struct sk_buff_head *msg, struct sk_buff_head *cpy) 560 { 561 struct sk_buff *skb, *_skb; 562 563 skb_queue_walk(msg, skb) { 564 _skb = skb_clone(skb, GFP_ATOMIC); 565 if (!_skb) { 566 __skb_queue_purge(cpy); 567 pr_err_ratelimited("Failed to clone buffer chain\n"); 568 return false; 569 } 570 __skb_queue_tail(cpy, _skb); 571 } 572 return true; 573 } 574 575 /** 576 * tipc_msg_lookup_dest(): try to find new destination for named message 577 * @skb: the buffer containing the message. 578 * @err: error code to be used by caller if lookup fails 579 * Does not consume buffer 580 * Returns true if a destination is found, false otherwise 581 */ 582 bool tipc_msg_lookup_dest(struct net *net, struct sk_buff *skb, int *err) 583 { 584 struct tipc_msg *msg = buf_msg(skb); 585 u32 dport, dnode; 586 u32 onode = tipc_own_addr(net); 587 588 if (!msg_isdata(msg)) 589 return false; 590 if (!msg_named(msg)) 591 return false; 592 if (msg_errcode(msg)) 593 return false; 594 *err = TIPC_ERR_NO_NAME; 595 if (skb_linearize(skb)) 596 return false; 597 msg = buf_msg(skb); 598 if (msg_reroute_cnt(msg)) 599 return false; 600 dnode = tipc_scope2node(net, msg_lookup_scope(msg)); 601 dport = tipc_nametbl_translate(net, msg_nametype(msg), 602 msg_nameinst(msg), &dnode); 603 if (!dport) 604 return false; 605 msg_incr_reroute_cnt(msg); 606 if (dnode != onode) 607 msg_set_prevnode(msg, onode); 608 msg_set_destnode(msg, dnode); 609 msg_set_destport(msg, dport); 610 *err = TIPC_OK; 611 612 if (!skb_cloned(skb)) 613 return true; 614 615 return true; 616 } 617 618 /* tipc_msg_assemble() - assemble chain of fragments into one message 619 */ 620 bool tipc_msg_assemble(struct sk_buff_head *list) 621 { 622 struct sk_buff *skb, *tmp = NULL; 623 624 if (skb_queue_len(list) == 1) 625 return true; 626 627 while ((skb = __skb_dequeue(list))) { 628 skb->next = NULL; 629 if (tipc_buf_append(&tmp, &skb)) { 630 __skb_queue_tail(list, skb); 631 return true; 632 } 633 if (!tmp) 634 break; 635 } 636 __skb_queue_purge(list); 637 __skb_queue_head_init(list); 638 pr_warn("Failed do assemble buffer\n"); 639 return false; 640 } 641 642 /* tipc_msg_reassemble() - clone a buffer chain of fragments and 643 * reassemble the clones into one message 644 */ 645 bool tipc_msg_reassemble(struct sk_buff_head *list, struct sk_buff_head *rcvq) 646 { 647 struct sk_buff *skb, *_skb; 648 struct sk_buff *frag = NULL; 649 struct sk_buff *head = NULL; 650 int hdr_len; 651 652 /* Copy header if single buffer */ 653 if (skb_queue_len(list) == 1) { 654 skb = skb_peek(list); 655 hdr_len = skb_headroom(skb) + msg_hdr_sz(buf_msg(skb)); 656 _skb = __pskb_copy(skb, hdr_len, GFP_ATOMIC); 657 if (!_skb) 658 return false; 659 __skb_queue_tail(rcvq, _skb); 660 return true; 661 } 662 663 /* Clone all fragments and reassemble */ 664 skb_queue_walk(list, skb) { 665 frag = skb_clone(skb, GFP_ATOMIC); 666 if (!frag) 667 goto error; 668 frag->next = NULL; 669 if (tipc_buf_append(&head, &frag)) 670 break; 671 if (!head) 672 goto error; 673 } 674 __skb_queue_tail(rcvq, frag); 675 return true; 676 error: 677 pr_warn("Failed do clone local mcast rcv buffer\n"); 678 kfree_skb(head); 679 return false; 680 } 681 682 bool tipc_msg_pskb_copy(u32 dst, struct sk_buff_head *msg, 683 struct sk_buff_head *cpy) 684 { 685 struct sk_buff *skb, *_skb; 686 687 skb_queue_walk(msg, skb) { 688 _skb = pskb_copy(skb, GFP_ATOMIC); 689 if (!_skb) { 690 __skb_queue_purge(cpy); 691 return false; 692 } 693 msg_set_destnode(buf_msg(_skb), dst); 694 __skb_queue_tail(cpy, _skb); 695 } 696 return true; 697 } 698 699 /* tipc_skb_queue_sorted(); sort pkt into list according to sequence number 700 * @list: list to be appended to 701 * @seqno: sequence number of buffer to add 702 * @skb: buffer to add 703 */ 704 void __tipc_skb_queue_sorted(struct sk_buff_head *list, u16 seqno, 705 struct sk_buff *skb) 706 { 707 struct sk_buff *_skb, *tmp; 708 709 if (skb_queue_empty(list) || less(seqno, buf_seqno(skb_peek(list)))) { 710 __skb_queue_head(list, skb); 711 return; 712 } 713 714 if (more(seqno, buf_seqno(skb_peek_tail(list)))) { 715 __skb_queue_tail(list, skb); 716 return; 717 } 718 719 skb_queue_walk_safe(list, _skb, tmp) { 720 if (more(seqno, buf_seqno(_skb))) 721 continue; 722 if (seqno == buf_seqno(_skb)) 723 break; 724 __skb_queue_before(list, _skb, skb); 725 return; 726 } 727 kfree_skb(skb); 728 } 729 730 void tipc_skb_reject(struct net *net, int err, struct sk_buff *skb, 731 struct sk_buff_head *xmitq) 732 { 733 if (tipc_msg_reverse(tipc_own_addr(net), &skb, err)) 734 __skb_queue_tail(xmitq, skb); 735 } 736