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1/*
2 * net/tipc/msg.c: TIPC message header routines
3 *
4 * Copyright (c) 2000-2006, 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 "core.h"
38#include "msg.h"
39
40u32 tipc_msg_tot_importance(struct tipc_msg *m)
41{
42 if (likely(msg_isdata(m))) {
43 if (likely(msg_orignode(m) == tipc_own_addr))
44 return msg_importance(m);
45 return msg_importance(m) + 4;
46 }
47 if ((msg_user(m) == MSG_FRAGMENTER) &&
48 (msg_type(m) == FIRST_FRAGMENT))
49 return msg_importance(msg_get_wrapped(m));
50 return msg_importance(m);
51}
52
53
54void tipc_msg_init(struct tipc_msg *m, u32 user, u32 type, u32 hsize,
55 u32 destnode)
56{
57 memset(m, 0, hsize);
58 msg_set_version(m);
59 msg_set_user(m, user);
60 msg_set_hdr_sz(m, hsize);
61 msg_set_size(m, hsize);
62 msg_set_prevnode(m, tipc_own_addr);
63 msg_set_type(m, type);
64 msg_set_orignode(m, tipc_own_addr);
65 msg_set_destnode(m, destnode);
66}
67
68/**
69 * tipc_msg_build - create message using specified header and data
70 *
71 * Note: Caller must not hold any locks in case copy_from_user() is interrupted!
72 *
73 * Returns message data size or errno
74 */
75int tipc_msg_build(struct tipc_msg *hdr, struct iovec const *msg_sect,
76 unsigned int len, int max_size, struct sk_buff **buf)
77{
78 int dsz, sz, hsz;
79 unsigned char *to;
80
81 dsz = len;
82 hsz = msg_hdr_sz(hdr);
83 sz = hsz + dsz;
84 msg_set_size(hdr, sz);
85 if (unlikely(sz > max_size)) {
86 *buf = NULL;
87 return dsz;
88 }
89
90 *buf = tipc_buf_acquire(sz);
91 if (!(*buf))
92 return -ENOMEM;
93 skb_copy_to_linear_data(*buf, hdr, hsz);
94 to = (*buf)->data + hsz;
95 if (len && memcpy_fromiovecend(to, msg_sect, 0, dsz)) {
96 kfree_skb(*buf);
97 *buf = NULL;
98 return -EFAULT;
99 }
100 return dsz;
101}
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
47static 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 */
61struct 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
75void 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
91struct 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 */
122int 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;
186err:
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 */
204bool tipc_msg_validate(struct sk_buff *skb)
205{
206 struct tipc_msg *msg;
207 int msz, hsz;
208
209 if (unlikely(TIPC_SKB_CB(skb)->validated))
210 return true;
211 if (unlikely(!pskb_may_pull(skb, MIN_H_SIZE)))
212 return false;
213
214 hsz = msg_hdr_sz(buf_msg(skb));
215 if (unlikely(hsz < MIN_H_SIZE) || (hsz > MAX_H_SIZE))
216 return false;
217 if (unlikely(!pskb_may_pull(skb, hsz)))
218 return false;
219
220 msg = buf_msg(skb);
221 if (unlikely(msg_version(msg) != TIPC_VERSION))
222 return false;
223
224 msz = msg_size(msg);
225 if (unlikely(msz < hsz))
226 return false;
227 if (unlikely((msz - hsz) > TIPC_MAX_USER_MSG_SIZE))
228 return false;
229 if (unlikely(skb->len < msz))
230 return false;
231
232 TIPC_SKB_CB(skb)->validated = true;
233 return true;
234}
235
236/**
237 * tipc_msg_build - create buffer chain containing specified header and data
238 * @mhdr: Message header, to be prepended to data
239 * @m: User message
240 * @dsz: Total length of user data
241 * @pktmax: Max packet size that can be used
242 * @list: Buffer or chain of buffers to be returned to caller
243 *
244 * Returns message data size or errno: -ENOMEM, -EFAULT
245 */
246int tipc_msg_build(struct tipc_msg *mhdr, struct msghdr *m,
247 int offset, int dsz, int pktmax, struct sk_buff_head *list)
248{
249 int mhsz = msg_hdr_sz(mhdr);
250 int msz = mhsz + dsz;
251 int pktno = 1;
252 int pktsz;
253 int pktrem = pktmax;
254 int drem = dsz;
255 struct tipc_msg pkthdr;
256 struct sk_buff *skb;
257 char *pktpos;
258 int rc;
259
260 msg_set_size(mhdr, msz);
261
262 /* No fragmentation needed? */
263 if (likely(msz <= pktmax)) {
264 skb = tipc_buf_acquire(msz, GFP_KERNEL);
265 if (unlikely(!skb))
266 return -ENOMEM;
267 skb_orphan(skb);
268 __skb_queue_tail(list, skb);
269 skb_copy_to_linear_data(skb, mhdr, mhsz);
270 pktpos = skb->data + mhsz;
271 if (copy_from_iter_full(pktpos, dsz, &m->msg_iter))
272 return dsz;
273 rc = -EFAULT;
274 goto error;
275 }
276
277 /* Prepare reusable fragment header */
278 tipc_msg_init(msg_prevnode(mhdr), &pkthdr, MSG_FRAGMENTER,
279 FIRST_FRAGMENT, INT_H_SIZE, msg_destnode(mhdr));
280 msg_set_size(&pkthdr, pktmax);
281 msg_set_fragm_no(&pkthdr, pktno);
282 msg_set_importance(&pkthdr, msg_importance(mhdr));
283
284 /* Prepare first fragment */
285 skb = tipc_buf_acquire(pktmax, GFP_KERNEL);
286 if (!skb)
287 return -ENOMEM;
288 skb_orphan(skb);
289 __skb_queue_tail(list, skb);
290 pktpos = skb->data;
291 skb_copy_to_linear_data(skb, &pkthdr, INT_H_SIZE);
292 pktpos += INT_H_SIZE;
293 pktrem -= INT_H_SIZE;
294 skb_copy_to_linear_data_offset(skb, INT_H_SIZE, mhdr, mhsz);
295 pktpos += mhsz;
296 pktrem -= mhsz;
297
298 do {
299 if (drem < pktrem)
300 pktrem = drem;
301
302 if (!copy_from_iter_full(pktpos, pktrem, &m->msg_iter)) {
303 rc = -EFAULT;
304 goto error;
305 }
306 drem -= pktrem;
307
308 if (!drem)
309 break;
310
311 /* Prepare new fragment: */
312 if (drem < (pktmax - INT_H_SIZE))
313 pktsz = drem + INT_H_SIZE;
314 else
315 pktsz = pktmax;
316 skb = tipc_buf_acquire(pktsz, GFP_KERNEL);
317 if (!skb) {
318 rc = -ENOMEM;
319 goto error;
320 }
321 skb_orphan(skb);
322 __skb_queue_tail(list, skb);
323 msg_set_type(&pkthdr, FRAGMENT);
324 msg_set_size(&pkthdr, pktsz);
325 msg_set_fragm_no(&pkthdr, ++pktno);
326 skb_copy_to_linear_data(skb, &pkthdr, INT_H_SIZE);
327 pktpos = skb->data + INT_H_SIZE;
328 pktrem = pktsz - INT_H_SIZE;
329
330 } while (1);
331 msg_set_type(buf_msg(skb), LAST_FRAGMENT);
332 return dsz;
333error:
334 __skb_queue_purge(list);
335 __skb_queue_head_init(list);
336 return rc;
337}
338
339/**
340 * tipc_msg_bundle(): Append contents of a buffer to tail of an existing one
341 * @skb: the buffer to append to ("bundle")
342 * @msg: message to be appended
343 * @mtu: max allowable size for the bundle buffer
344 * Consumes buffer if successful
345 * Returns true if bundling could be performed, otherwise false
346 */
347bool tipc_msg_bundle(struct sk_buff *skb, struct tipc_msg *msg, u32 mtu)
348{
349 struct tipc_msg *bmsg;
350 unsigned int bsz;
351 unsigned int msz = msg_size(msg);
352 u32 start, pad;
353 u32 max = mtu - INT_H_SIZE;
354
355 if (likely(msg_user(msg) == MSG_FRAGMENTER))
356 return false;
357 if (!skb)
358 return false;
359 bmsg = buf_msg(skb);
360 bsz = msg_size(bmsg);
361 start = align(bsz);
362 pad = start - bsz;
363
364 if (unlikely(msg_user(msg) == TUNNEL_PROTOCOL))
365 return false;
366 if (unlikely(msg_user(msg) == BCAST_PROTOCOL))
367 return false;
368 if (unlikely(msg_user(bmsg) != MSG_BUNDLER))
369 return false;
370 if (unlikely(skb_tailroom(skb) < (pad + msz)))
371 return false;
372 if (unlikely(max < (start + msz)))
373 return false;
374 if ((msg_importance(msg) < TIPC_SYSTEM_IMPORTANCE) &&
375 (msg_importance(bmsg) == TIPC_SYSTEM_IMPORTANCE))
376 return false;
377
378 skb_put(skb, pad + msz);
379 skb_copy_to_linear_data_offset(skb, start, msg, msz);
380 msg_set_size(bmsg, start + msz);
381 msg_set_msgcnt(bmsg, msg_msgcnt(bmsg) + 1);
382 return true;
383}
384
385/**
386 * tipc_msg_extract(): extract bundled inner packet from buffer
387 * @skb: buffer to be extracted from.
388 * @iskb: extracted inner buffer, to be returned
389 * @pos: position in outer message of msg to be extracted.
390 * Returns position of next msg
391 * Consumes outer buffer when last packet extracted
392 * Returns true when when there is an extracted buffer, otherwise false
393 */
394bool tipc_msg_extract(struct sk_buff *skb, struct sk_buff **iskb, int *pos)
395{
396 struct tipc_msg *msg;
397 int imsz, offset;
398
399 *iskb = NULL;
400 if (unlikely(skb_linearize(skb)))
401 goto none;
402
403 msg = buf_msg(skb);
404 offset = msg_hdr_sz(msg) + *pos;
405 if (unlikely(offset > (msg_size(msg) - MIN_H_SIZE)))
406 goto none;
407
408 *iskb = skb_clone(skb, GFP_ATOMIC);
409 if (unlikely(!*iskb))
410 goto none;
411 skb_pull(*iskb, offset);
412 imsz = msg_size(buf_msg(*iskb));
413 skb_trim(*iskb, imsz);
414 if (unlikely(!tipc_msg_validate(*iskb)))
415 goto none;
416 *pos += align(imsz);
417 return true;
418none:
419 kfree_skb(skb);
420 kfree_skb(*iskb);
421 *iskb = NULL;
422 return false;
423}
424
425/**
426 * tipc_msg_make_bundle(): Create bundle buf and append message to its tail
427 * @list: the buffer chain, where head is the buffer to replace/append
428 * @skb: buffer to be created, appended to and returned in case of success
429 * @msg: message to be appended
430 * @mtu: max allowable size for the bundle buffer, inclusive header
431 * @dnode: destination node for message. (Not always present in header)
432 * Returns true if success, otherwise false
433 */
434bool tipc_msg_make_bundle(struct sk_buff **skb, struct tipc_msg *msg,
435 u32 mtu, u32 dnode)
436{
437 struct sk_buff *_skb;
438 struct tipc_msg *bmsg;
439 u32 msz = msg_size(msg);
440 u32 max = mtu - INT_H_SIZE;
441
442 if (msg_user(msg) == MSG_FRAGMENTER)
443 return false;
444 if (msg_user(msg) == TUNNEL_PROTOCOL)
445 return false;
446 if (msg_user(msg) == BCAST_PROTOCOL)
447 return false;
448 if (msz > (max / 2))
449 return false;
450
451 _skb = tipc_buf_acquire(max, GFP_ATOMIC);
452 if (!_skb)
453 return false;
454
455 skb_trim(_skb, INT_H_SIZE);
456 bmsg = buf_msg(_skb);
457 tipc_msg_init(msg_prevnode(msg), bmsg, MSG_BUNDLER, 0,
458 INT_H_SIZE, dnode);
459 if (msg_isdata(msg))
460 msg_set_importance(bmsg, TIPC_CRITICAL_IMPORTANCE);
461 else
462 msg_set_importance(bmsg, TIPC_SYSTEM_IMPORTANCE);
463 msg_set_seqno(bmsg, msg_seqno(msg));
464 msg_set_ack(bmsg, msg_ack(msg));
465 msg_set_bcast_ack(bmsg, msg_bcast_ack(msg));
466 tipc_msg_bundle(_skb, msg, mtu);
467 *skb = _skb;
468 return true;
469}
470
471/**
472 * tipc_msg_reverse(): swap source and destination addresses and add error code
473 * @own_node: originating node id for reversed message
474 * @skb: buffer containing message to be reversed; may be replaced.
475 * @err: error code to be set in message, if any
476 * Consumes buffer at failure
477 * Returns true if success, otherwise false
478 */
479bool tipc_msg_reverse(u32 own_node, struct sk_buff **skb, int err)
480{
481 struct sk_buff *_skb = *skb;
482 struct tipc_msg *hdr = buf_msg(_skb);
483 struct tipc_msg ohdr;
484 int dlen = min_t(uint, msg_data_sz(hdr), MAX_FORWARD_SIZE);
485
486 if (skb_linearize(_skb))
487 goto exit;
488 hdr = buf_msg(_skb);
489 if (msg_dest_droppable(hdr))
490 goto exit;
491 if (msg_errcode(hdr))
492 goto exit;
493
494 /* Take a copy of original header before altering message */
495 memcpy(&ohdr, hdr, msg_hdr_sz(hdr));
496
497 /* Never return SHORT header; expand by replacing buffer if necessary */
498 if (msg_short(hdr)) {
499 *skb = tipc_buf_acquire(BASIC_H_SIZE + dlen, GFP_ATOMIC);
500 if (!*skb)
501 goto exit;
502 memcpy((*skb)->data + BASIC_H_SIZE, msg_data(hdr), dlen);
503 kfree_skb(_skb);
504 _skb = *skb;
505 hdr = buf_msg(_skb);
506 memcpy(hdr, &ohdr, BASIC_H_SIZE);
507 msg_set_hdr_sz(hdr, BASIC_H_SIZE);
508 }
509
510 if (skb_cloned(_skb) &&
511 pskb_expand_head(_skb, BUF_HEADROOM, BUF_TAILROOM, GFP_KERNEL))
512 goto exit;
513
514 /* Now reverse the concerned fields */
515 msg_set_errcode(hdr, err);
516 msg_set_origport(hdr, msg_destport(&ohdr));
517 msg_set_destport(hdr, msg_origport(&ohdr));
518 msg_set_destnode(hdr, msg_prevnode(&ohdr));
519 msg_set_prevnode(hdr, own_node);
520 msg_set_orignode(hdr, own_node);
521 msg_set_size(hdr, msg_hdr_sz(hdr) + dlen);
522 skb_trim(_skb, msg_size(hdr));
523 skb_orphan(_skb);
524 return true;
525exit:
526 kfree_skb(_skb);
527 *skb = NULL;
528 return false;
529}
530
531/**
532 * tipc_msg_lookup_dest(): try to find new destination for named message
533 * @skb: the buffer containing the message.
534 * @err: error code to be used by caller if lookup fails
535 * Does not consume buffer
536 * Returns true if a destination is found, false otherwise
537 */
538bool tipc_msg_lookup_dest(struct net *net, struct sk_buff *skb, int *err)
539{
540 struct tipc_msg *msg = buf_msg(skb);
541 u32 dport, dnode;
542 u32 onode = tipc_own_addr(net);
543
544 if (!msg_isdata(msg))
545 return false;
546 if (!msg_named(msg))
547 return false;
548 if (msg_errcode(msg))
549 return false;
550 *err = -TIPC_ERR_NO_NAME;
551 if (skb_linearize(skb))
552 return false;
553 msg = buf_msg(skb);
554 if (msg_reroute_cnt(msg))
555 return false;
556 dnode = addr_domain(net, msg_lookup_scope(msg));
557 dport = tipc_nametbl_translate(net, msg_nametype(msg),
558 msg_nameinst(msg), &dnode);
559 if (!dport)
560 return false;
561 msg_incr_reroute_cnt(msg);
562 if (dnode != onode)
563 msg_set_prevnode(msg, onode);
564 msg_set_destnode(msg, dnode);
565 msg_set_destport(msg, dport);
566 *err = TIPC_OK;
567 return true;
568}
569
570/* tipc_msg_reassemble() - clone a buffer chain of fragments and
571 * reassemble the clones into one message
572 */
573bool tipc_msg_reassemble(struct sk_buff_head *list, struct sk_buff_head *rcvq)
574{
575 struct sk_buff *skb, *_skb;
576 struct sk_buff *frag = NULL;
577 struct sk_buff *head = NULL;
578 int hdr_len;
579
580 /* Copy header if single buffer */
581 if (skb_queue_len(list) == 1) {
582 skb = skb_peek(list);
583 hdr_len = skb_headroom(skb) + msg_hdr_sz(buf_msg(skb));
584 _skb = __pskb_copy(skb, hdr_len, GFP_ATOMIC);
585 if (!_skb)
586 return false;
587 __skb_queue_tail(rcvq, _skb);
588 return true;
589 }
590
591 /* Clone all fragments and reassemble */
592 skb_queue_walk(list, skb) {
593 frag = skb_clone(skb, GFP_ATOMIC);
594 if (!frag)
595 goto error;
596 frag->next = NULL;
597 if (tipc_buf_append(&head, &frag))
598 break;
599 if (!head)
600 goto error;
601 }
602 __skb_queue_tail(rcvq, frag);
603 return true;
604error:
605 pr_warn("Failed do clone local mcast rcv buffer\n");
606 kfree_skb(head);
607 return false;
608}
609
610/* tipc_skb_queue_sorted(); sort pkt into list according to sequence number
611 * @list: list to be appended to
612 * @seqno: sequence number of buffer to add
613 * @skb: buffer to add
614 */
615void __tipc_skb_queue_sorted(struct sk_buff_head *list, u16 seqno,
616 struct sk_buff *skb)
617{
618 struct sk_buff *_skb, *tmp;
619
620 if (skb_queue_empty(list) || less(seqno, buf_seqno(skb_peek(list)))) {
621 __skb_queue_head(list, skb);
622 return;
623 }
624
625 if (more(seqno, buf_seqno(skb_peek_tail(list)))) {
626 __skb_queue_tail(list, skb);
627 return;
628 }
629
630 skb_queue_walk_safe(list, _skb, tmp) {
631 if (more(seqno, buf_seqno(_skb)))
632 continue;
633 if (seqno == buf_seqno(_skb))
634 break;
635 __skb_queue_before(list, _skb, skb);
636 return;
637 }
638 kfree_skb(skb);
639}