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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
45static unsigned int align(unsigned int i)
46{
47 return (i + 3) & ~3u;
48}
49
50/**
51 * tipc_buf_acquire - creates a TIPC message buffer
52 * @size: message size (including TIPC header)
53 *
54 * Returns a new buffer with data pointers set to the specified size.
55 *
56 * NOTE: Headroom is reserved to allow prepending of a data link header.
57 * There may also be unrequested tailroom present at the buffer's end.
58 */
59struct sk_buff *tipc_buf_acquire(u32 size)
60{
61 struct sk_buff *skb;
62 unsigned int buf_size = (BUF_HEADROOM + size + 3) & ~3u;
63
64 skb = alloc_skb_fclone(buf_size, GFP_ATOMIC);
65 if (skb) {
66 skb_reserve(skb, BUF_HEADROOM);
67 skb_put(skb, size);
68 skb->next = NULL;
69 }
70 return skb;
71}
72
73void tipc_msg_init(u32 own_node, struct tipc_msg *m, u32 user, u32 type,
74 u32 hsize, u32 dnode)
75{
76 memset(m, 0, hsize);
77 msg_set_version(m);
78 msg_set_user(m, user);
79 msg_set_hdr_sz(m, hsize);
80 msg_set_size(m, hsize);
81 msg_set_prevnode(m, own_node);
82 msg_set_type(m, type);
83 if (hsize > SHORT_H_SIZE) {
84 msg_set_orignode(m, own_node);
85 msg_set_destnode(m, dnode);
86 }
87}
88
89struct sk_buff *tipc_msg_create(uint user, uint type,
90 uint hdr_sz, uint data_sz, u32 dnode,
91 u32 onode, u32 dport, u32 oport, int errcode)
92{
93 struct tipc_msg *msg;
94 struct sk_buff *buf;
95
96 buf = tipc_buf_acquire(hdr_sz + data_sz);
97 if (unlikely(!buf))
98 return NULL;
99
100 msg = buf_msg(buf);
101 tipc_msg_init(onode, msg, user, type, hdr_sz, dnode);
102 msg_set_size(msg, hdr_sz + data_sz);
103 msg_set_origport(msg, oport);
104 msg_set_destport(msg, dport);
105 msg_set_errcode(msg, errcode);
106 if (hdr_sz > SHORT_H_SIZE) {
107 msg_set_orignode(msg, onode);
108 msg_set_destnode(msg, dnode);
109 }
110 return buf;
111}
112
113/* tipc_buf_append(): Append a buffer to the fragment list of another buffer
114 * @*headbuf: in: NULL for first frag, otherwise value returned from prev call
115 * out: set when successful non-complete reassembly, otherwise NULL
116 * @*buf: in: the buffer to append. Always defined
117 * out: head buf after successful complete reassembly, otherwise NULL
118 * Returns 1 when reassembly complete, otherwise 0
119 */
120int tipc_buf_append(struct sk_buff **headbuf, struct sk_buff **buf)
121{
122 struct sk_buff *head = *headbuf;
123 struct sk_buff *frag = *buf;
124 struct sk_buff *tail = NULL;
125 struct tipc_msg *msg;
126 u32 fragid;
127 int delta;
128 bool headstolen;
129
130 if (!frag)
131 goto err;
132
133 msg = buf_msg(frag);
134 fragid = msg_type(msg);
135 frag->next = NULL;
136 skb_pull(frag, msg_hdr_sz(msg));
137
138 if (fragid == FIRST_FRAGMENT) {
139 if (unlikely(head))
140 goto err;
141 if (unlikely(skb_unclone(frag, GFP_ATOMIC)))
142 goto err;
143 head = *headbuf = frag;
144 *buf = NULL;
145 TIPC_SKB_CB(head)->tail = NULL;
146 if (skb_is_nonlinear(head)) {
147 skb_walk_frags(head, tail) {
148 TIPC_SKB_CB(head)->tail = tail;
149 }
150 } else {
151 skb_frag_list_init(head);
152 }
153 return 0;
154 }
155
156 if (!head)
157 goto err;
158
159 if (skb_try_coalesce(head, frag, &headstolen, &delta)) {
160 kfree_skb_partial(frag, headstolen);
161 } else {
162 tail = TIPC_SKB_CB(head)->tail;
163 if (!skb_has_frag_list(head))
164 skb_shinfo(head)->frag_list = frag;
165 else
166 tail->next = frag;
167 head->truesize += frag->truesize;
168 head->data_len += frag->len;
169 head->len += frag->len;
170 TIPC_SKB_CB(head)->tail = frag;
171 }
172
173 if (fragid == LAST_FRAGMENT) {
174 TIPC_SKB_CB(head)->validated = false;
175 if (unlikely(!tipc_msg_validate(head)))
176 goto err;
177 *buf = head;
178 TIPC_SKB_CB(head)->tail = NULL;
179 *headbuf = NULL;
180 return 1;
181 }
182 *buf = NULL;
183 return 0;
184err:
185 kfree_skb(*buf);
186 kfree_skb(*headbuf);
187 *buf = *headbuf = NULL;
188 return 0;
189}
190
191/* tipc_msg_validate - validate basic format of received message
192 *
193 * This routine ensures a TIPC message has an acceptable header, and at least
194 * as much data as the header indicates it should. The routine also ensures
195 * that the entire message header is stored in the main fragment of the message
196 * buffer, to simplify future access to message header fields.
197 *
198 * Note: Having extra info present in the message header or data areas is OK.
199 * TIPC will ignore the excess, under the assumption that it is optional info
200 * introduced by a later release of the protocol.
201 */
202bool tipc_msg_validate(struct sk_buff *skb)
203{
204 struct tipc_msg *msg;
205 int msz, hsz;
206
207 if (unlikely(TIPC_SKB_CB(skb)->validated))
208 return true;
209 if (unlikely(!pskb_may_pull(skb, MIN_H_SIZE)))
210 return false;
211
212 hsz = msg_hdr_sz(buf_msg(skb));
213 if (unlikely(hsz < MIN_H_SIZE) || (hsz > MAX_H_SIZE))
214 return false;
215 if (unlikely(!pskb_may_pull(skb, hsz)))
216 return false;
217
218 msg = buf_msg(skb);
219 if (unlikely(msg_version(msg) != TIPC_VERSION))
220 return false;
221
222 msz = msg_size(msg);
223 if (unlikely(msz < hsz))
224 return false;
225 if (unlikely((msz - hsz) > TIPC_MAX_USER_MSG_SIZE))
226 return false;
227 if (unlikely(skb->len < msz))
228 return false;
229
230 TIPC_SKB_CB(skb)->validated = true;
231 return true;
232}
233
234/**
235 * tipc_msg_build - create buffer chain containing specified header and data
236 * @mhdr: Message header, to be prepended to data
237 * @m: User message
238 * @dsz: Total length of user data
239 * @pktmax: Max packet size that can be used
240 * @list: Buffer or chain of buffers to be returned to caller
241 *
242 * Returns message data size or errno: -ENOMEM, -EFAULT
243 */
244int tipc_msg_build(struct tipc_msg *mhdr, struct msghdr *m,
245 int offset, int dsz, int pktmax, struct sk_buff_head *list)
246{
247 int mhsz = msg_hdr_sz(mhdr);
248 int msz = mhsz + dsz;
249 int pktno = 1;
250 int pktsz;
251 int pktrem = pktmax;
252 int drem = dsz;
253 struct tipc_msg pkthdr;
254 struct sk_buff *skb;
255 char *pktpos;
256 int rc;
257
258 msg_set_size(mhdr, msz);
259
260 /* No fragmentation needed? */
261 if (likely(msz <= pktmax)) {
262 skb = tipc_buf_acquire(msz);
263 if (unlikely(!skb))
264 return -ENOMEM;
265 skb_orphan(skb);
266 __skb_queue_tail(list, skb);
267 skb_copy_to_linear_data(skb, mhdr, mhsz);
268 pktpos = skb->data + mhsz;
269 if (copy_from_iter(pktpos, dsz, &m->msg_iter) == dsz)
270 return dsz;
271 rc = -EFAULT;
272 goto error;
273 }
274
275 /* Prepare reusable fragment header */
276 tipc_msg_init(msg_prevnode(mhdr), &pkthdr, MSG_FRAGMENTER,
277 FIRST_FRAGMENT, INT_H_SIZE, msg_destnode(mhdr));
278 msg_set_size(&pkthdr, pktmax);
279 msg_set_fragm_no(&pkthdr, pktno);
280 msg_set_importance(&pkthdr, msg_importance(mhdr));
281
282 /* Prepare first fragment */
283 skb = tipc_buf_acquire(pktmax);
284 if (!skb)
285 return -ENOMEM;
286 skb_orphan(skb);
287 __skb_queue_tail(list, skb);
288 pktpos = skb->data;
289 skb_copy_to_linear_data(skb, &pkthdr, INT_H_SIZE);
290 pktpos += INT_H_SIZE;
291 pktrem -= INT_H_SIZE;
292 skb_copy_to_linear_data_offset(skb, INT_H_SIZE, mhdr, mhsz);
293 pktpos += mhsz;
294 pktrem -= mhsz;
295
296 do {
297 if (drem < pktrem)
298 pktrem = drem;
299
300 if (copy_from_iter(pktpos, pktrem, &m->msg_iter) != pktrem) {
301 rc = -EFAULT;
302 goto error;
303 }
304 drem -= pktrem;
305
306 if (!drem)
307 break;
308
309 /* Prepare new fragment: */
310 if (drem < (pktmax - INT_H_SIZE))
311 pktsz = drem + INT_H_SIZE;
312 else
313 pktsz = pktmax;
314 skb = tipc_buf_acquire(pktsz);
315 if (!skb) {
316 rc = -ENOMEM;
317 goto error;
318 }
319 skb_orphan(skb);
320 __skb_queue_tail(list, skb);
321 msg_set_type(&pkthdr, FRAGMENT);
322 msg_set_size(&pkthdr, pktsz);
323 msg_set_fragm_no(&pkthdr, ++pktno);
324 skb_copy_to_linear_data(skb, &pkthdr, INT_H_SIZE);
325 pktpos = skb->data + INT_H_SIZE;
326 pktrem = pktsz - INT_H_SIZE;
327
328 } while (1);
329 msg_set_type(buf_msg(skb), LAST_FRAGMENT);
330 return dsz;
331error:
332 __skb_queue_purge(list);
333 __skb_queue_head_init(list);
334 return rc;
335}
336
337/**
338 * tipc_msg_bundle(): Append contents of a buffer to tail of an existing one
339 * @skb: the buffer to append to ("bundle")
340 * @msg: message to be appended
341 * @mtu: max allowable size for the bundle buffer
342 * Consumes buffer if successful
343 * Returns true if bundling could be performed, otherwise false
344 */
345bool tipc_msg_bundle(struct sk_buff *skb, struct tipc_msg *msg, u32 mtu)
346{
347 struct tipc_msg *bmsg;
348 unsigned int bsz;
349 unsigned int msz = msg_size(msg);
350 u32 start, pad;
351 u32 max = mtu - INT_H_SIZE;
352
353 if (likely(msg_user(msg) == MSG_FRAGMENTER))
354 return false;
355 if (!skb)
356 return false;
357 bmsg = buf_msg(skb);
358 bsz = msg_size(bmsg);
359 start = align(bsz);
360 pad = start - bsz;
361
362 if (unlikely(msg_user(msg) == TUNNEL_PROTOCOL))
363 return false;
364 if (unlikely(msg_user(msg) == BCAST_PROTOCOL))
365 return false;
366 if (unlikely(msg_user(bmsg) != MSG_BUNDLER))
367 return false;
368 if (unlikely(skb_tailroom(skb) < (pad + msz)))
369 return false;
370 if (unlikely(max < (start + msz)))
371 return false;
372 if ((msg_importance(msg) < TIPC_SYSTEM_IMPORTANCE) &&
373 (msg_importance(bmsg) == TIPC_SYSTEM_IMPORTANCE))
374 return false;
375
376 skb_put(skb, pad + msz);
377 skb_copy_to_linear_data_offset(skb, start, msg, msz);
378 msg_set_size(bmsg, start + msz);
379 msg_set_msgcnt(bmsg, msg_msgcnt(bmsg) + 1);
380 return true;
381}
382
383/**
384 * tipc_msg_extract(): extract bundled inner packet from buffer
385 * @skb: buffer to be extracted from.
386 * @iskb: extracted inner buffer, to be returned
387 * @pos: position in outer message of msg to be extracted.
388 * Returns position of next msg
389 * Consumes outer buffer when last packet extracted
390 * Returns true when when there is an extracted buffer, otherwise false
391 */
392bool tipc_msg_extract(struct sk_buff *skb, struct sk_buff **iskb, int *pos)
393{
394 struct tipc_msg *msg;
395 int imsz, offset;
396
397 *iskb = NULL;
398 if (unlikely(skb_linearize(skb)))
399 goto none;
400
401 msg = buf_msg(skb);
402 offset = msg_hdr_sz(msg) + *pos;
403 if (unlikely(offset > (msg_size(msg) - MIN_H_SIZE)))
404 goto none;
405
406 *iskb = skb_clone(skb, GFP_ATOMIC);
407 if (unlikely(!*iskb))
408 goto none;
409 skb_pull(*iskb, offset);
410 imsz = msg_size(buf_msg(*iskb));
411 skb_trim(*iskb, imsz);
412 if (unlikely(!tipc_msg_validate(*iskb)))
413 goto none;
414 *pos += align(imsz);
415 return true;
416none:
417 kfree_skb(skb);
418 kfree_skb(*iskb);
419 *iskb = NULL;
420 return false;
421}
422
423/**
424 * tipc_msg_make_bundle(): Create bundle buf and append message to its tail
425 * @list: the buffer chain, where head is the buffer to replace/append
426 * @skb: buffer to be created, appended to and returned in case of success
427 * @msg: message to be appended
428 * @mtu: max allowable size for the bundle buffer, inclusive header
429 * @dnode: destination node for message. (Not always present in header)
430 * Returns true if success, otherwise false
431 */
432bool tipc_msg_make_bundle(struct sk_buff **skb, struct tipc_msg *msg,
433 u32 mtu, u32 dnode)
434{
435 struct sk_buff *_skb;
436 struct tipc_msg *bmsg;
437 u32 msz = msg_size(msg);
438 u32 max = mtu - INT_H_SIZE;
439
440 if (msg_user(msg) == MSG_FRAGMENTER)
441 return false;
442 if (msg_user(msg) == TUNNEL_PROTOCOL)
443 return false;
444 if (msg_user(msg) == BCAST_PROTOCOL)
445 return false;
446 if (msz > (max / 2))
447 return false;
448
449 _skb = tipc_buf_acquire(max);
450 if (!_skb)
451 return false;
452
453 skb_trim(_skb, INT_H_SIZE);
454 bmsg = buf_msg(_skb);
455 tipc_msg_init(msg_prevnode(msg), bmsg, MSG_BUNDLER, 0,
456 INT_H_SIZE, dnode);
457 if (msg_isdata(msg))
458 msg_set_importance(bmsg, TIPC_CRITICAL_IMPORTANCE);
459 else
460 msg_set_importance(bmsg, TIPC_SYSTEM_IMPORTANCE);
461 msg_set_seqno(bmsg, msg_seqno(msg));
462 msg_set_ack(bmsg, msg_ack(msg));
463 msg_set_bcast_ack(bmsg, msg_bcast_ack(msg));
464 tipc_msg_bundle(_skb, msg, mtu);
465 *skb = _skb;
466 return true;
467}
468
469/**
470 * tipc_msg_reverse(): swap source and destination addresses and add error code
471 * @own_node: originating node id for reversed message
472 * @skb: buffer containing message to be reversed; may be replaced.
473 * @err: error code to be set in message, if any
474 * Consumes buffer at failure
475 * Returns true if success, otherwise false
476 */
477bool tipc_msg_reverse(u32 own_node, struct sk_buff **skb, int err)
478{
479 struct sk_buff *_skb = *skb;
480 struct tipc_msg *hdr = buf_msg(_skb);
481 struct tipc_msg ohdr;
482 int dlen = min_t(uint, msg_data_sz(hdr), MAX_FORWARD_SIZE);
483
484 if (skb_linearize(_skb))
485 goto exit;
486 hdr = buf_msg(_skb);
487 if (msg_dest_droppable(hdr))
488 goto exit;
489 if (msg_errcode(hdr))
490 goto exit;
491
492 /* Take a copy of original header before altering message */
493 memcpy(&ohdr, hdr, msg_hdr_sz(hdr));
494
495 /* Never return SHORT header; expand by replacing buffer if necessary */
496 if (msg_short(hdr)) {
497 *skb = tipc_buf_acquire(BASIC_H_SIZE + dlen);
498 if (!*skb)
499 goto exit;
500 memcpy((*skb)->data + BASIC_H_SIZE, msg_data(hdr), dlen);
501 kfree_skb(_skb);
502 _skb = *skb;
503 hdr = buf_msg(_skb);
504 memcpy(hdr, &ohdr, BASIC_H_SIZE);
505 msg_set_hdr_sz(hdr, BASIC_H_SIZE);
506 }
507
508 /* Now reverse the concerned fields */
509 msg_set_errcode(hdr, err);
510 msg_set_origport(hdr, msg_destport(&ohdr));
511 msg_set_destport(hdr, msg_origport(&ohdr));
512 msg_set_destnode(hdr, msg_prevnode(&ohdr));
513 msg_set_prevnode(hdr, own_node);
514 msg_set_orignode(hdr, own_node);
515 msg_set_size(hdr, msg_hdr_sz(hdr) + dlen);
516 skb_trim(_skb, msg_size(hdr));
517 skb_orphan(_skb);
518 return true;
519exit:
520 kfree_skb(_skb);
521 *skb = NULL;
522 return false;
523}
524
525/**
526 * tipc_msg_lookup_dest(): try to find new destination for named message
527 * @skb: the buffer containing the message.
528 * @err: error code to be used by caller if lookup fails
529 * Does not consume buffer
530 * Returns true if a destination is found, false otherwise
531 */
532bool tipc_msg_lookup_dest(struct net *net, struct sk_buff *skb, int *err)
533{
534 struct tipc_msg *msg = buf_msg(skb);
535 u32 dport, dnode;
536 u32 onode = tipc_own_addr(net);
537
538 if (!msg_isdata(msg))
539 return false;
540 if (!msg_named(msg))
541 return false;
542 if (msg_errcode(msg))
543 return false;
544 *err = -TIPC_ERR_NO_NAME;
545 if (skb_linearize(skb))
546 return false;
547 msg = buf_msg(skb);
548 if (msg_reroute_cnt(msg))
549 return false;
550 dnode = addr_domain(net, msg_lookup_scope(msg));
551 dport = tipc_nametbl_translate(net, msg_nametype(msg),
552 msg_nameinst(msg), &dnode);
553 if (!dport)
554 return false;
555 msg_incr_reroute_cnt(msg);
556 if (dnode != onode)
557 msg_set_prevnode(msg, onode);
558 msg_set_destnode(msg, dnode);
559 msg_set_destport(msg, dport);
560 *err = TIPC_OK;
561 return true;
562}
563
564/* tipc_msg_reassemble() - clone a buffer chain of fragments and
565 * reassemble the clones into one message
566 */
567bool tipc_msg_reassemble(struct sk_buff_head *list, struct sk_buff_head *rcvq)
568{
569 struct sk_buff *skb, *_skb;
570 struct sk_buff *frag = NULL;
571 struct sk_buff *head = NULL;
572 int hdr_len;
573
574 /* Copy header if single buffer */
575 if (skb_queue_len(list) == 1) {
576 skb = skb_peek(list);
577 hdr_len = skb_headroom(skb) + msg_hdr_sz(buf_msg(skb));
578 _skb = __pskb_copy(skb, hdr_len, GFP_ATOMIC);
579 if (!_skb)
580 return false;
581 __skb_queue_tail(rcvq, _skb);
582 return true;
583 }
584
585 /* Clone all fragments and reassemble */
586 skb_queue_walk(list, skb) {
587 frag = skb_clone(skb, GFP_ATOMIC);
588 if (!frag)
589 goto error;
590 frag->next = NULL;
591 if (tipc_buf_append(&head, &frag))
592 break;
593 if (!head)
594 goto error;
595 }
596 __skb_queue_tail(rcvq, frag);
597 return true;
598error:
599 pr_warn("Failed do clone local mcast rcv buffer\n");
600 kfree_skb(head);
601 return false;
602}
603
604/* tipc_skb_queue_sorted(); sort pkt into list according to sequence number
605 * @list: list to be appended to
606 * @seqno: sequence number of buffer to add
607 * @skb: buffer to add
608 */
609void __tipc_skb_queue_sorted(struct sk_buff_head *list, u16 seqno,
610 struct sk_buff *skb)
611{
612 struct sk_buff *_skb, *tmp;
613
614 if (skb_queue_empty(list) || less(seqno, buf_seqno(skb_peek(list)))) {
615 __skb_queue_head(list, skb);
616 return;
617 }
618
619 if (more(seqno, buf_seqno(skb_peek_tail(list)))) {
620 __skb_queue_tail(list, skb);
621 return;
622 }
623
624 skb_queue_walk_safe(list, _skb, tmp) {
625 if (more(seqno, buf_seqno(_skb)))
626 continue;
627 if (seqno == buf_seqno(_skb))
628 break;
629 __skb_queue_before(list, _skb, skb);
630 return;
631 }
632 kfree_skb(skb);
633}
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#include "crypto.h"
43
44#define BUF_ALIGN(x) ALIGN(x, 4)
45#define MAX_FORWARD_SIZE 1024
46#ifdef CONFIG_TIPC_CRYPTO
47#define BUF_HEADROOM ALIGN(((LL_MAX_HEADER + 48) + EHDR_MAX_SIZE), 16)
48#define BUF_OVERHEAD (BUF_HEADROOM + TIPC_AES_GCM_TAG_SIZE)
49#else
50#define BUF_HEADROOM (LL_MAX_HEADER + 48)
51#define BUF_OVERHEAD BUF_HEADROOM
52#endif
53
54const int one_page_mtu = PAGE_SIZE - SKB_DATA_ALIGN(BUF_OVERHEAD) -
55 SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
56
57/**
58 * tipc_buf_acquire - creates a TIPC message buffer
59 * @size: message size (including TIPC header)
60 * @gfp: memory allocation flags
61 *
62 * Return: a new buffer with data pointers set to the specified size.
63 *
64 * NOTE:
65 * Headroom is reserved to allow prepending of a data link header.
66 * There may also be unrequested tailroom present at the buffer's end.
67 */
68struct sk_buff *tipc_buf_acquire(u32 size, gfp_t gfp)
69{
70 struct sk_buff *skb;
71
72 skb = alloc_skb_fclone(BUF_OVERHEAD + size, gfp);
73 if (skb) {
74 skb_reserve(skb, BUF_HEADROOM);
75 skb_put(skb, size);
76 skb->next = NULL;
77 }
78 return skb;
79}
80
81void tipc_msg_init(u32 own_node, struct tipc_msg *m, u32 user, u32 type,
82 u32 hsize, u32 dnode)
83{
84 memset(m, 0, hsize);
85 msg_set_version(m);
86 msg_set_user(m, user);
87 msg_set_hdr_sz(m, hsize);
88 msg_set_size(m, hsize);
89 msg_set_prevnode(m, own_node);
90 msg_set_type(m, type);
91 if (hsize > SHORT_H_SIZE) {
92 msg_set_orignode(m, own_node);
93 msg_set_destnode(m, dnode);
94 }
95}
96
97struct sk_buff *tipc_msg_create(uint user, uint type,
98 uint hdr_sz, uint data_sz, u32 dnode,
99 u32 onode, u32 dport, u32 oport, int errcode)
100{
101 struct tipc_msg *msg;
102 struct sk_buff *buf;
103
104 buf = tipc_buf_acquire(hdr_sz + data_sz, GFP_ATOMIC);
105 if (unlikely(!buf))
106 return NULL;
107
108 msg = buf_msg(buf);
109 tipc_msg_init(onode, msg, user, type, hdr_sz, dnode);
110 msg_set_size(msg, hdr_sz + data_sz);
111 msg_set_origport(msg, oport);
112 msg_set_destport(msg, dport);
113 msg_set_errcode(msg, errcode);
114 return buf;
115}
116
117/* tipc_buf_append(): Append a buffer to the fragment list of another buffer
118 * @*headbuf: in: NULL for first frag, otherwise value returned from prev call
119 * out: set when successful non-complete reassembly, otherwise NULL
120 * @*buf: in: the buffer to append. Always defined
121 * out: head buf after successful complete reassembly, otherwise NULL
122 * Returns 1 when reassembly complete, otherwise 0
123 */
124int tipc_buf_append(struct sk_buff **headbuf, struct sk_buff **buf)
125{
126 struct sk_buff *head = *headbuf;
127 struct sk_buff *frag = *buf;
128 struct sk_buff *tail = NULL;
129 struct tipc_msg *msg;
130 u32 fragid;
131 int delta;
132 bool headstolen;
133
134 if (!frag)
135 goto err;
136
137 msg = buf_msg(frag);
138 fragid = msg_type(msg);
139 frag->next = NULL;
140 skb_pull(frag, msg_hdr_sz(msg));
141
142 if (fragid == FIRST_FRAGMENT) {
143 if (unlikely(head))
144 goto err;
145 if (skb_has_frag_list(frag) && __skb_linearize(frag))
146 goto err;
147 *buf = NULL;
148 frag = skb_unshare(frag, GFP_ATOMIC);
149 if (unlikely(!frag))
150 goto err;
151 head = *headbuf = frag;
152 TIPC_SKB_CB(head)->tail = NULL;
153 return 0;
154 }
155
156 if (!head)
157 goto err;
158
159 /* Either the input skb ownership is transferred to headskb
160 * or the input skb is freed, clear the reference to avoid
161 * bad access on error path.
162 */
163 *buf = NULL;
164 if (skb_try_coalesce(head, frag, &headstolen, &delta)) {
165 kfree_skb_partial(frag, headstolen);
166 } else {
167 tail = TIPC_SKB_CB(head)->tail;
168 if (!skb_has_frag_list(head))
169 skb_shinfo(head)->frag_list = frag;
170 else
171 tail->next = frag;
172 head->truesize += frag->truesize;
173 head->data_len += frag->len;
174 head->len += frag->len;
175 TIPC_SKB_CB(head)->tail = frag;
176 }
177
178 if (fragid == LAST_FRAGMENT) {
179 TIPC_SKB_CB(head)->validated = 0;
180 if (unlikely(!tipc_msg_validate(&head)))
181 goto err;
182 *buf = head;
183 TIPC_SKB_CB(head)->tail = NULL;
184 *headbuf = NULL;
185 return 1;
186 }
187 return 0;
188err:
189 kfree_skb(*buf);
190 kfree_skb(*headbuf);
191 *buf = *headbuf = NULL;
192 return 0;
193}
194
195/**
196 * tipc_msg_append(): Append data to tail of an existing buffer queue
197 * @_hdr: header to be used
198 * @m: the data to be appended
199 * @mss: max allowable size of buffer
200 * @dlen: size of data to be appended
201 * @txq: queue to append to
202 *
203 * Return: the number of 1k blocks appended or errno value
204 */
205int tipc_msg_append(struct tipc_msg *_hdr, struct msghdr *m, int dlen,
206 int mss, struct sk_buff_head *txq)
207{
208 struct sk_buff *skb;
209 int accounted, total, curr;
210 int mlen, cpy, rem = dlen;
211 struct tipc_msg *hdr;
212
213 skb = skb_peek_tail(txq);
214 accounted = skb ? msg_blocks(buf_msg(skb)) : 0;
215 total = accounted;
216
217 do {
218 if (!skb || skb->len >= mss) {
219 skb = tipc_buf_acquire(mss, GFP_KERNEL);
220 if (unlikely(!skb))
221 return -ENOMEM;
222 skb_orphan(skb);
223 skb_trim(skb, MIN_H_SIZE);
224 hdr = buf_msg(skb);
225 skb_copy_to_linear_data(skb, _hdr, MIN_H_SIZE);
226 msg_set_hdr_sz(hdr, MIN_H_SIZE);
227 msg_set_size(hdr, MIN_H_SIZE);
228 __skb_queue_tail(txq, skb);
229 total += 1;
230 }
231 hdr = buf_msg(skb);
232 curr = msg_blocks(hdr);
233 mlen = msg_size(hdr);
234 cpy = min_t(size_t, rem, mss - mlen);
235 if (cpy != copy_from_iter(skb->data + mlen, cpy, &m->msg_iter))
236 return -EFAULT;
237 msg_set_size(hdr, mlen + cpy);
238 skb_put(skb, cpy);
239 rem -= cpy;
240 total += msg_blocks(hdr) - curr;
241 } while (rem > 0);
242 return total - accounted;
243}
244
245/* tipc_msg_validate - validate basic format of received message
246 *
247 * This routine ensures a TIPC message has an acceptable header, and at least
248 * as much data as the header indicates it should. The routine also ensures
249 * that the entire message header is stored in the main fragment of the message
250 * buffer, to simplify future access to message header fields.
251 *
252 * Note: Having extra info present in the message header or data areas is OK.
253 * TIPC will ignore the excess, under the assumption that it is optional info
254 * introduced by a later release of the protocol.
255 */
256bool tipc_msg_validate(struct sk_buff **_skb)
257{
258 struct sk_buff *skb = *_skb;
259 struct tipc_msg *hdr;
260 int msz, hsz;
261
262 /* Ensure that flow control ratio condition is satisfied */
263 if (unlikely(skb->truesize / buf_roundup_len(skb) >= 4)) {
264 skb = skb_copy_expand(skb, BUF_HEADROOM, 0, GFP_ATOMIC);
265 if (!skb)
266 return false;
267 kfree_skb(*_skb);
268 *_skb = skb;
269 }
270
271 if (unlikely(TIPC_SKB_CB(skb)->validated))
272 return true;
273
274 if (unlikely(!pskb_may_pull(skb, MIN_H_SIZE)))
275 return false;
276
277 hsz = msg_hdr_sz(buf_msg(skb));
278 if (unlikely(hsz < MIN_H_SIZE) || (hsz > MAX_H_SIZE))
279 return false;
280 if (unlikely(!pskb_may_pull(skb, hsz)))
281 return false;
282
283 hdr = buf_msg(skb);
284 if (unlikely(msg_version(hdr) != TIPC_VERSION))
285 return false;
286
287 msz = msg_size(hdr);
288 if (unlikely(msz < hsz))
289 return false;
290 if (unlikely((msz - hsz) > TIPC_MAX_USER_MSG_SIZE))
291 return false;
292 if (unlikely(skb->len < msz))
293 return false;
294
295 TIPC_SKB_CB(skb)->validated = 1;
296 return true;
297}
298
299/**
300 * tipc_msg_fragment - build a fragment skb list for TIPC message
301 *
302 * @skb: TIPC message skb
303 * @hdr: internal msg header to be put on the top of the fragments
304 * @pktmax: max size of a fragment incl. the header
305 * @frags: returned fragment skb list
306 *
307 * Return: 0 if the fragmentation is successful, otherwise: -EINVAL
308 * or -ENOMEM
309 */
310int tipc_msg_fragment(struct sk_buff *skb, const struct tipc_msg *hdr,
311 int pktmax, struct sk_buff_head *frags)
312{
313 int pktno, nof_fragms, dsz, dmax, eat;
314 struct tipc_msg *_hdr;
315 struct sk_buff *_skb;
316 u8 *data;
317
318 /* Non-linear buffer? */
319 if (skb_linearize(skb))
320 return -ENOMEM;
321
322 data = (u8 *)skb->data;
323 dsz = msg_size(buf_msg(skb));
324 dmax = pktmax - INT_H_SIZE;
325 if (dsz <= dmax || !dmax)
326 return -EINVAL;
327
328 nof_fragms = dsz / dmax + 1;
329 for (pktno = 1; pktno <= nof_fragms; pktno++) {
330 if (pktno < nof_fragms)
331 eat = dmax;
332 else
333 eat = dsz % dmax;
334 /* Allocate a new fragment */
335 _skb = tipc_buf_acquire(INT_H_SIZE + eat, GFP_ATOMIC);
336 if (!_skb)
337 goto error;
338 skb_orphan(_skb);
339 __skb_queue_tail(frags, _skb);
340 /* Copy header & data to the fragment */
341 skb_copy_to_linear_data(_skb, hdr, INT_H_SIZE);
342 skb_copy_to_linear_data_offset(_skb, INT_H_SIZE, data, eat);
343 data += eat;
344 /* Update the fragment's header */
345 _hdr = buf_msg(_skb);
346 msg_set_fragm_no(_hdr, pktno);
347 msg_set_nof_fragms(_hdr, nof_fragms);
348 msg_set_size(_hdr, INT_H_SIZE + eat);
349 }
350 return 0;
351
352error:
353 __skb_queue_purge(frags);
354 __skb_queue_head_init(frags);
355 return -ENOMEM;
356}
357
358/**
359 * tipc_msg_build - create buffer chain containing specified header and data
360 * @mhdr: Message header, to be prepended to data
361 * @m: User message
362 * @offset: buffer offset for fragmented messages (FIXME)
363 * @dsz: Total length of user data
364 * @pktmax: Max packet size that can be used
365 * @list: Buffer or chain of buffers to be returned to caller
366 *
367 * Note that the recursive call we are making here is safe, since it can
368 * logically go only one further level down.
369 *
370 * Return: message data size or errno: -ENOMEM, -EFAULT
371 */
372int tipc_msg_build(struct tipc_msg *mhdr, struct msghdr *m, int offset,
373 int dsz, int pktmax, struct sk_buff_head *list)
374{
375 int mhsz = msg_hdr_sz(mhdr);
376 struct tipc_msg pkthdr;
377 int msz = mhsz + dsz;
378 int pktrem = pktmax;
379 struct sk_buff *skb;
380 int drem = dsz;
381 int pktno = 1;
382 char *pktpos;
383 int pktsz;
384 int rc;
385
386 msg_set_size(mhdr, msz);
387
388 /* No fragmentation needed? */
389 if (likely(msz <= pktmax)) {
390 skb = tipc_buf_acquire(msz, GFP_KERNEL);
391
392 /* Fall back to smaller MTU if node local message */
393 if (unlikely(!skb)) {
394 if (pktmax != MAX_MSG_SIZE)
395 return -ENOMEM;
396 rc = tipc_msg_build(mhdr, m, offset, dsz,
397 one_page_mtu, list);
398 if (rc != dsz)
399 return rc;
400 if (tipc_msg_assemble(list))
401 return dsz;
402 return -ENOMEM;
403 }
404 skb_orphan(skb);
405 __skb_queue_tail(list, skb);
406 skb_copy_to_linear_data(skb, mhdr, mhsz);
407 pktpos = skb->data + mhsz;
408 if (copy_from_iter_full(pktpos, dsz, &m->msg_iter))
409 return dsz;
410 rc = -EFAULT;
411 goto error;
412 }
413
414 /* Prepare reusable fragment header */
415 tipc_msg_init(msg_prevnode(mhdr), &pkthdr, MSG_FRAGMENTER,
416 FIRST_FRAGMENT, INT_H_SIZE, msg_destnode(mhdr));
417 msg_set_size(&pkthdr, pktmax);
418 msg_set_fragm_no(&pkthdr, pktno);
419 msg_set_importance(&pkthdr, msg_importance(mhdr));
420
421 /* Prepare first fragment */
422 skb = tipc_buf_acquire(pktmax, GFP_KERNEL);
423 if (!skb)
424 return -ENOMEM;
425 skb_orphan(skb);
426 __skb_queue_tail(list, skb);
427 pktpos = skb->data;
428 skb_copy_to_linear_data(skb, &pkthdr, INT_H_SIZE);
429 pktpos += INT_H_SIZE;
430 pktrem -= INT_H_SIZE;
431 skb_copy_to_linear_data_offset(skb, INT_H_SIZE, mhdr, mhsz);
432 pktpos += mhsz;
433 pktrem -= mhsz;
434
435 do {
436 if (drem < pktrem)
437 pktrem = drem;
438
439 if (!copy_from_iter_full(pktpos, pktrem, &m->msg_iter)) {
440 rc = -EFAULT;
441 goto error;
442 }
443 drem -= pktrem;
444
445 if (!drem)
446 break;
447
448 /* Prepare new fragment: */
449 if (drem < (pktmax - INT_H_SIZE))
450 pktsz = drem + INT_H_SIZE;
451 else
452 pktsz = pktmax;
453 skb = tipc_buf_acquire(pktsz, GFP_KERNEL);
454 if (!skb) {
455 rc = -ENOMEM;
456 goto error;
457 }
458 skb_orphan(skb);
459 __skb_queue_tail(list, skb);
460 msg_set_type(&pkthdr, FRAGMENT);
461 msg_set_size(&pkthdr, pktsz);
462 msg_set_fragm_no(&pkthdr, ++pktno);
463 skb_copy_to_linear_data(skb, &pkthdr, INT_H_SIZE);
464 pktpos = skb->data + INT_H_SIZE;
465 pktrem = pktsz - INT_H_SIZE;
466
467 } while (1);
468 msg_set_type(buf_msg(skb), LAST_FRAGMENT);
469 return dsz;
470error:
471 __skb_queue_purge(list);
472 __skb_queue_head_init(list);
473 return rc;
474}
475
476/**
477 * tipc_msg_bundle - Append contents of a buffer to tail of an existing one
478 * @bskb: the bundle buffer to append to
479 * @msg: message to be appended
480 * @max: max allowable size for the bundle buffer
481 *
482 * Return: "true" if bundling has been performed, otherwise "false"
483 */
484static bool tipc_msg_bundle(struct sk_buff *bskb, struct tipc_msg *msg,
485 u32 max)
486{
487 struct tipc_msg *bmsg = buf_msg(bskb);
488 u32 msz, bsz, offset, pad;
489
490 msz = msg_size(msg);
491 bsz = msg_size(bmsg);
492 offset = BUF_ALIGN(bsz);
493 pad = offset - bsz;
494
495 if (unlikely(skb_tailroom(bskb) < (pad + msz)))
496 return false;
497 if (unlikely(max < (offset + msz)))
498 return false;
499
500 skb_put(bskb, pad + msz);
501 skb_copy_to_linear_data_offset(bskb, offset, msg, msz);
502 msg_set_size(bmsg, offset + msz);
503 msg_set_msgcnt(bmsg, msg_msgcnt(bmsg) + 1);
504 return true;
505}
506
507/**
508 * tipc_msg_try_bundle - Try to bundle a new message to the last one
509 * @tskb: the last/target message to which the new one will be appended
510 * @skb: the new message skb pointer
511 * @mss: max message size (header inclusive)
512 * @dnode: destination node for the message
513 * @new_bundle: if this call made a new bundle or not
514 *
515 * Return: "true" if the new message skb is potential for bundling this time or
516 * later, in the case a bundling has been done this time, the skb is consumed
517 * (the skb pointer = NULL).
518 * Otherwise, "false" if the skb cannot be bundled at all.
519 */
520bool tipc_msg_try_bundle(struct sk_buff *tskb, struct sk_buff **skb, u32 mss,
521 u32 dnode, bool *new_bundle)
522{
523 struct tipc_msg *msg, *inner, *outer;
524 u32 tsz;
525
526 /* First, check if the new buffer is suitable for bundling */
527 msg = buf_msg(*skb);
528 if (msg_user(msg) == MSG_FRAGMENTER)
529 return false;
530 if (msg_user(msg) == TUNNEL_PROTOCOL)
531 return false;
532 if (msg_user(msg) == BCAST_PROTOCOL)
533 return false;
534 if (mss <= INT_H_SIZE + msg_size(msg))
535 return false;
536
537 /* Ok, but the last/target buffer can be empty? */
538 if (unlikely(!tskb))
539 return true;
540
541 /* Is it a bundle already? Try to bundle the new message to it */
542 if (msg_user(buf_msg(tskb)) == MSG_BUNDLER) {
543 *new_bundle = false;
544 goto bundle;
545 }
546
547 /* Make a new bundle of the two messages if possible */
548 tsz = msg_size(buf_msg(tskb));
549 if (unlikely(mss < BUF_ALIGN(INT_H_SIZE + tsz) + msg_size(msg)))
550 return true;
551 if (unlikely(pskb_expand_head(tskb, INT_H_SIZE, mss - tsz - INT_H_SIZE,
552 GFP_ATOMIC)))
553 return true;
554 inner = buf_msg(tskb);
555 skb_push(tskb, INT_H_SIZE);
556 outer = buf_msg(tskb);
557 tipc_msg_init(msg_prevnode(inner), outer, MSG_BUNDLER, 0, INT_H_SIZE,
558 dnode);
559 msg_set_importance(outer, msg_importance(inner));
560 msg_set_size(outer, INT_H_SIZE + tsz);
561 msg_set_msgcnt(outer, 1);
562 *new_bundle = true;
563
564bundle:
565 if (likely(tipc_msg_bundle(tskb, msg, mss))) {
566 consume_skb(*skb);
567 *skb = NULL;
568 }
569 return true;
570}
571
572/**
573 * tipc_msg_extract(): extract bundled inner packet from buffer
574 * @skb: buffer to be extracted from.
575 * @iskb: extracted inner buffer, to be returned
576 * @pos: position in outer message of msg to be extracted.
577 * Returns position of next msg.
578 * Consumes outer buffer when last packet extracted
579 * Return: true when there is an extracted buffer, otherwise false
580 */
581bool tipc_msg_extract(struct sk_buff *skb, struct sk_buff **iskb, int *pos)
582{
583 struct tipc_msg *hdr, *ihdr;
584 int imsz;
585
586 *iskb = NULL;
587 if (unlikely(skb_linearize(skb)))
588 goto none;
589
590 hdr = buf_msg(skb);
591 if (unlikely(*pos > (msg_data_sz(hdr) - MIN_H_SIZE)))
592 goto none;
593
594 ihdr = (struct tipc_msg *)(msg_data(hdr) + *pos);
595 imsz = msg_size(ihdr);
596
597 if ((*pos + imsz) > msg_data_sz(hdr))
598 goto none;
599
600 *iskb = tipc_buf_acquire(imsz, GFP_ATOMIC);
601 if (!*iskb)
602 goto none;
603
604 skb_copy_to_linear_data(*iskb, ihdr, imsz);
605 if (unlikely(!tipc_msg_validate(iskb)))
606 goto none;
607
608 *pos += BUF_ALIGN(imsz);
609 return true;
610none:
611 kfree_skb(skb);
612 kfree_skb(*iskb);
613 *iskb = NULL;
614 return false;
615}
616
617/**
618 * tipc_msg_reverse(): swap source and destination addresses and add error code
619 * @own_node: originating node id for reversed message
620 * @skb: buffer containing message to be reversed; will be consumed
621 * @err: error code to be set in message, if any
622 * Replaces consumed buffer with new one when successful
623 * Return: true if success, otherwise false
624 */
625bool tipc_msg_reverse(u32 own_node, struct sk_buff **skb, int err)
626{
627 struct sk_buff *_skb = *skb;
628 struct tipc_msg *_hdr, *hdr;
629 int hlen, dlen;
630
631 if (skb_linearize(_skb))
632 goto exit;
633 _hdr = buf_msg(_skb);
634 dlen = min_t(uint, msg_data_sz(_hdr), MAX_FORWARD_SIZE);
635 hlen = msg_hdr_sz(_hdr);
636
637 if (msg_dest_droppable(_hdr))
638 goto exit;
639 if (msg_errcode(_hdr))
640 goto exit;
641
642 /* Never return SHORT header */
643 if (hlen == SHORT_H_SIZE)
644 hlen = BASIC_H_SIZE;
645
646 /* Don't return data along with SYN+, - sender has a clone */
647 if (msg_is_syn(_hdr) && err == TIPC_ERR_OVERLOAD)
648 dlen = 0;
649
650 /* Allocate new buffer to return */
651 *skb = tipc_buf_acquire(hlen + dlen, GFP_ATOMIC);
652 if (!*skb)
653 goto exit;
654 memcpy((*skb)->data, _skb->data, msg_hdr_sz(_hdr));
655 memcpy((*skb)->data + hlen, msg_data(_hdr), dlen);
656
657 /* Build reverse header in new buffer */
658 hdr = buf_msg(*skb);
659 msg_set_hdr_sz(hdr, hlen);
660 msg_set_errcode(hdr, err);
661 msg_set_non_seq(hdr, 0);
662 msg_set_origport(hdr, msg_destport(_hdr));
663 msg_set_destport(hdr, msg_origport(_hdr));
664 msg_set_destnode(hdr, msg_prevnode(_hdr));
665 msg_set_prevnode(hdr, own_node);
666 msg_set_orignode(hdr, own_node);
667 msg_set_size(hdr, hlen + dlen);
668 skb_orphan(_skb);
669 kfree_skb(_skb);
670 return true;
671exit:
672 kfree_skb(_skb);
673 *skb = NULL;
674 return false;
675}
676
677bool tipc_msg_skb_clone(struct sk_buff_head *msg, struct sk_buff_head *cpy)
678{
679 struct sk_buff *skb, *_skb;
680
681 skb_queue_walk(msg, skb) {
682 _skb = skb_clone(skb, GFP_ATOMIC);
683 if (!_skb) {
684 __skb_queue_purge(cpy);
685 pr_err_ratelimited("Failed to clone buffer chain\n");
686 return false;
687 }
688 __skb_queue_tail(cpy, _skb);
689 }
690 return true;
691}
692
693/**
694 * tipc_msg_lookup_dest(): try to find new destination for named message
695 * @net: pointer to associated network namespace
696 * @skb: the buffer containing the message.
697 * @err: error code to be used by caller if lookup fails
698 * Does not consume buffer
699 * Return: true if a destination is found, false otherwise
700 */
701bool tipc_msg_lookup_dest(struct net *net, struct sk_buff *skb, int *err)
702{
703 struct tipc_msg *msg = buf_msg(skb);
704 u32 scope = msg_lookup_scope(msg);
705 u32 self = tipc_own_addr(net);
706 u32 inst = msg_nameinst(msg);
707 struct tipc_socket_addr sk;
708 struct tipc_uaddr ua;
709
710 if (!msg_isdata(msg))
711 return false;
712 if (!msg_named(msg))
713 return false;
714 if (msg_errcode(msg))
715 return false;
716 *err = TIPC_ERR_NO_NAME;
717 if (skb_linearize(skb))
718 return false;
719 msg = buf_msg(skb);
720 if (msg_reroute_cnt(msg))
721 return false;
722 tipc_uaddr(&ua, TIPC_SERVICE_RANGE, scope,
723 msg_nametype(msg), inst, inst);
724 sk.node = tipc_scope2node(net, scope);
725 if (!tipc_nametbl_lookup_anycast(net, &ua, &sk))
726 return false;
727 msg_incr_reroute_cnt(msg);
728 if (sk.node != self)
729 msg_set_prevnode(msg, self);
730 msg_set_destnode(msg, sk.node);
731 msg_set_destport(msg, sk.ref);
732 *err = TIPC_OK;
733
734 return true;
735}
736
737/* tipc_msg_assemble() - assemble chain of fragments into one message
738 */
739bool tipc_msg_assemble(struct sk_buff_head *list)
740{
741 struct sk_buff *skb, *tmp = NULL;
742
743 if (skb_queue_len(list) == 1)
744 return true;
745
746 while ((skb = __skb_dequeue(list))) {
747 skb->next = NULL;
748 if (tipc_buf_append(&tmp, &skb)) {
749 __skb_queue_tail(list, skb);
750 return true;
751 }
752 if (!tmp)
753 break;
754 }
755 __skb_queue_purge(list);
756 __skb_queue_head_init(list);
757 pr_warn("Failed do assemble buffer\n");
758 return false;
759}
760
761/* tipc_msg_reassemble() - clone a buffer chain of fragments and
762 * reassemble the clones into one message
763 */
764bool tipc_msg_reassemble(struct sk_buff_head *list, struct sk_buff_head *rcvq)
765{
766 struct sk_buff *skb, *_skb;
767 struct sk_buff *frag = NULL;
768 struct sk_buff *head = NULL;
769 int hdr_len;
770
771 /* Copy header if single buffer */
772 if (skb_queue_len(list) == 1) {
773 skb = skb_peek(list);
774 hdr_len = skb_headroom(skb) + msg_hdr_sz(buf_msg(skb));
775 _skb = __pskb_copy(skb, hdr_len, GFP_ATOMIC);
776 if (!_skb)
777 return false;
778 __skb_queue_tail(rcvq, _skb);
779 return true;
780 }
781
782 /* Clone all fragments and reassemble */
783 skb_queue_walk(list, skb) {
784 frag = skb_clone(skb, GFP_ATOMIC);
785 if (!frag)
786 goto error;
787 frag->next = NULL;
788 if (tipc_buf_append(&head, &frag))
789 break;
790 if (!head)
791 goto error;
792 }
793 __skb_queue_tail(rcvq, frag);
794 return true;
795error:
796 pr_warn("Failed do clone local mcast rcv buffer\n");
797 kfree_skb(head);
798 return false;
799}
800
801bool tipc_msg_pskb_copy(u32 dst, struct sk_buff_head *msg,
802 struct sk_buff_head *cpy)
803{
804 struct sk_buff *skb, *_skb;
805
806 skb_queue_walk(msg, skb) {
807 _skb = pskb_copy(skb, GFP_ATOMIC);
808 if (!_skb) {
809 __skb_queue_purge(cpy);
810 return false;
811 }
812 msg_set_destnode(buf_msg(_skb), dst);
813 __skb_queue_tail(cpy, _skb);
814 }
815 return true;
816}
817
818/* tipc_skb_queue_sorted(); sort pkt into list according to sequence number
819 * @list: list to be appended to
820 * @seqno: sequence number of buffer to add
821 * @skb: buffer to add
822 */
823bool __tipc_skb_queue_sorted(struct sk_buff_head *list, u16 seqno,
824 struct sk_buff *skb)
825{
826 struct sk_buff *_skb, *tmp;
827
828 if (skb_queue_empty(list) || less(seqno, buf_seqno(skb_peek(list)))) {
829 __skb_queue_head(list, skb);
830 return true;
831 }
832
833 if (more(seqno, buf_seqno(skb_peek_tail(list)))) {
834 __skb_queue_tail(list, skb);
835 return true;
836 }
837
838 skb_queue_walk_safe(list, _skb, tmp) {
839 if (more(seqno, buf_seqno(_skb)))
840 continue;
841 if (seqno == buf_seqno(_skb))
842 break;
843 __skb_queue_before(list, _skb, skb);
844 return true;
845 }
846 kfree_skb(skb);
847 return false;
848}
849
850void tipc_skb_reject(struct net *net, int err, struct sk_buff *skb,
851 struct sk_buff_head *xmitq)
852{
853 if (tipc_msg_reverse(tipc_own_addr(net), &skb, err))
854 __skb_queue_tail(xmitq, skb);
855}