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Commit | Line | Data |
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b97bf3fd PL |
1 | /* |
2 | * net/tipc/msg.c: TIPC message header routines | |
c4307285 | 3 | * |
cf2157f8 | 4 | * Copyright (c) 2000-2006, 2014-2015, Ericsson AB |
741de3e9 | 5 | * Copyright (c) 2005, 2010-2011, Wind River Systems |
b97bf3fd PL |
6 | * All rights reserved. |
7 | * | |
9ea1fd3c | 8 | * Redistribution and use in source and binary forms, with or without |
b97bf3fd PL |
9 | * modification, are permitted provided that the following conditions are met: |
10 | * | |
9ea1fd3c PL |
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. | |
b97bf3fd | 19 | * |
9ea1fd3c PL |
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 | |
b97bf3fd PL |
34 | * POSSIBILITY OF SUCH DAMAGE. |
35 | */ | |
36 | ||
c93d3baa | 37 | #include <net/sock.h> |
b97bf3fd | 38 | #include "core.h" |
b97bf3fd | 39 | #include "msg.h" |
5a379074 JPM |
40 | #include "addr.h" |
41 | #include "name_table.h" | |
b97bf3fd | 42 | |
8db1bae3 JPM |
43 | #define MAX_FORWARD_SIZE 1024 |
44 | ||
4f1688b2 | 45 | static unsigned int align(unsigned int i) |
23461e83 | 46 | { |
4f1688b2 | 47 | return (i + 3) & ~3u; |
23461e83 AS |
48 | } |
49 | ||
859fc7c0 YX |
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 | */ | |
59 | struct 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 | ||
c5898636 JPM |
73 | void tipc_msg_init(u32 own_node, struct tipc_msg *m, u32 user, u32 type, |
74 | u32 hsize, u32 dnode) | |
23461e83 AS |
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); | |
c5898636 | 81 | msg_set_prevnode(m, own_node); |
23461e83 | 82 | msg_set_type(m, type); |
1dd0bd2b | 83 | if (hsize > SHORT_H_SIZE) { |
c5898636 JPM |
84 | msg_set_orignode(m, own_node); |
85 | msg_set_destnode(m, dnode); | |
1dd0bd2b JPM |
86 | } |
87 | } | |
88 | ||
c5898636 | 89 | struct sk_buff *tipc_msg_create(uint user, uint type, |
34747539 YX |
90 | uint hdr_sz, uint data_sz, u32 dnode, |
91 | u32 onode, u32 dport, u32 oport, int errcode) | |
1dd0bd2b JPM |
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); | |
c5898636 | 101 | tipc_msg_init(onode, msg, user, type, hdr_sz, dnode); |
1dd0bd2b | 102 | msg_set_size(msg, hdr_sz + data_sz); |
1dd0bd2b JPM |
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; | |
23461e83 AS |
111 | } |
112 | ||
37e22164 | 113 | /* tipc_buf_append(): Append a buffer to the fragment list of another buffer |
29322d0d JPM |
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 | |
b2ad5e5f | 117 | * out: head buf after successful complete reassembly, otherwise NULL |
29322d0d | 118 | * Returns 1 when reassembly complete, otherwise 0 |
37e22164 JPM |
119 | */ |
120 | int 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; | |
13e9b997 JPM |
125 | struct tipc_msg *msg; |
126 | u32 fragid; | |
37e22164 | 127 | int delta; |
13e9b997 | 128 | bool headstolen; |
37e22164 | 129 | |
13e9b997 JPM |
130 | if (!frag) |
131 | goto err; | |
132 | ||
133 | msg = buf_msg(frag); | |
134 | fragid = msg_type(msg); | |
135 | frag->next = NULL; | |
37e22164 JPM |
136 | skb_pull(frag, msg_hdr_sz(msg)); |
137 | ||
138 | if (fragid == FIRST_FRAGMENT) { | |
13e9b997 JPM |
139 | if (unlikely(head)) |
140 | goto err; | |
141 | if (unlikely(skb_unclone(frag, GFP_ATOMIC))) | |
142 | goto err; | |
37e22164 JPM |
143 | head = *headbuf = frag; |
144 | skb_frag_list_init(head); | |
13e9b997 | 145 | TIPC_SKB_CB(head)->tail = NULL; |
29322d0d | 146 | *buf = NULL; |
37e22164 JPM |
147 | return 0; |
148 | } | |
13e9b997 | 149 | |
37e22164 | 150 | if (!head) |
13e9b997 JPM |
151 | goto err; |
152 | ||
37e22164 JPM |
153 | if (skb_try_coalesce(head, frag, &headstolen, &delta)) { |
154 | kfree_skb_partial(frag, headstolen); | |
155 | } else { | |
13e9b997 | 156 | tail = TIPC_SKB_CB(head)->tail; |
37e22164 JPM |
157 | if (!skb_has_frag_list(head)) |
158 | skb_shinfo(head)->frag_list = frag; | |
159 | else | |
160 | tail->next = frag; | |
161 | head->truesize += frag->truesize; | |
162 | head->data_len += frag->len; | |
163 | head->len += frag->len; | |
164 | TIPC_SKB_CB(head)->tail = frag; | |
165 | } | |
13e9b997 | 166 | |
37e22164 | 167 | if (fragid == LAST_FRAGMENT) { |
1149557d JPM |
168 | TIPC_SKB_CB(head)->validated = false; |
169 | if (unlikely(!tipc_msg_validate(head))) | |
170 | goto err; | |
37e22164 JPM |
171 | *buf = head; |
172 | TIPC_SKB_CB(head)->tail = NULL; | |
173 | *headbuf = NULL; | |
174 | return 1; | |
175 | } | |
176 | *buf = NULL; | |
177 | return 0; | |
13e9b997 | 178 | err: |
37e22164 JPM |
179 | pr_warn_ratelimited("Unable to build fragment list\n"); |
180 | kfree_skb(*buf); | |
29322d0d JPM |
181 | kfree_skb(*headbuf); |
182 | *buf = *headbuf = NULL; | |
37e22164 JPM |
183 | return 0; |
184 | } | |
4f1688b2 | 185 | |
cf2157f8 JPM |
186 | /* tipc_msg_validate - validate basic format of received message |
187 | * | |
188 | * This routine ensures a TIPC message has an acceptable header, and at least | |
189 | * as much data as the header indicates it should. The routine also ensures | |
190 | * that the entire message header is stored in the main fragment of the message | |
191 | * buffer, to simplify future access to message header fields. | |
192 | * | |
193 | * Note: Having extra info present in the message header or data areas is OK. | |
194 | * TIPC will ignore the excess, under the assumption that it is optional info | |
195 | * introduced by a later release of the protocol. | |
196 | */ | |
197 | bool tipc_msg_validate(struct sk_buff *skb) | |
198 | { | |
199 | struct tipc_msg *msg; | |
200 | int msz, hsz; | |
201 | ||
202 | if (unlikely(TIPC_SKB_CB(skb)->validated)) | |
203 | return true; | |
204 | if (unlikely(!pskb_may_pull(skb, MIN_H_SIZE))) | |
205 | return false; | |
206 | ||
207 | hsz = msg_hdr_sz(buf_msg(skb)); | |
208 | if (unlikely(hsz < MIN_H_SIZE) || (hsz > MAX_H_SIZE)) | |
209 | return false; | |
210 | if (unlikely(!pskb_may_pull(skb, hsz))) | |
211 | return false; | |
212 | ||
213 | msg = buf_msg(skb); | |
214 | if (unlikely(msg_version(msg) != TIPC_VERSION)) | |
215 | return false; | |
216 | ||
217 | msz = msg_size(msg); | |
218 | if (unlikely(msz < hsz)) | |
219 | return false; | |
220 | if (unlikely((msz - hsz) > TIPC_MAX_USER_MSG_SIZE)) | |
221 | return false; | |
222 | if (unlikely(skb->len < msz)) | |
223 | return false; | |
224 | ||
225 | TIPC_SKB_CB(skb)->validated = true; | |
226 | return true; | |
227 | } | |
067608e9 JPM |
228 | |
229 | /** | |
9fbfb8b1 | 230 | * tipc_msg_build - create buffer chain containing specified header and data |
067608e9 | 231 | * @mhdr: Message header, to be prepended to data |
45dcc687 | 232 | * @m: User message |
067608e9 JPM |
233 | * @dsz: Total length of user data |
234 | * @pktmax: Max packet size that can be used | |
a6ca1094 YX |
235 | * @list: Buffer or chain of buffers to be returned to caller |
236 | * | |
067608e9 JPM |
237 | * Returns message data size or errno: -ENOMEM, -EFAULT |
238 | */ | |
c5898636 | 239 | int tipc_msg_build(struct tipc_msg *mhdr, struct msghdr *m, |
34747539 | 240 | int offset, int dsz, int pktmax, struct sk_buff_head *list) |
067608e9 JPM |
241 | { |
242 | int mhsz = msg_hdr_sz(mhdr); | |
243 | int msz = mhsz + dsz; | |
244 | int pktno = 1; | |
245 | int pktsz; | |
246 | int pktrem = pktmax; | |
247 | int drem = dsz; | |
248 | struct tipc_msg pkthdr; | |
a6ca1094 | 249 | struct sk_buff *skb; |
067608e9 JPM |
250 | char *pktpos; |
251 | int rc; | |
a6ca1094 | 252 | |
067608e9 JPM |
253 | msg_set_size(mhdr, msz); |
254 | ||
255 | /* No fragmentation needed? */ | |
256 | if (likely(msz <= pktmax)) { | |
a6ca1094 YX |
257 | skb = tipc_buf_acquire(msz); |
258 | if (unlikely(!skb)) | |
067608e9 | 259 | return -ENOMEM; |
c93d3baa | 260 | skb_orphan(skb); |
a6ca1094 YX |
261 | __skb_queue_tail(list, skb); |
262 | skb_copy_to_linear_data(skb, mhdr, mhsz); | |
263 | pktpos = skb->data + mhsz; | |
f25dcc76 | 264 | if (copy_from_iter(pktpos, dsz, &m->msg_iter) == dsz) |
067608e9 JPM |
265 | return dsz; |
266 | rc = -EFAULT; | |
267 | goto error; | |
268 | } | |
269 | ||
270 | /* Prepare reusable fragment header */ | |
c5898636 JPM |
271 | tipc_msg_init(msg_prevnode(mhdr), &pkthdr, MSG_FRAGMENTER, |
272 | FIRST_FRAGMENT, INT_H_SIZE, msg_destnode(mhdr)); | |
067608e9 JPM |
273 | msg_set_size(&pkthdr, pktmax); |
274 | msg_set_fragm_no(&pkthdr, pktno); | |
e3eea1eb | 275 | msg_set_importance(&pkthdr, msg_importance(mhdr)); |
067608e9 JPM |
276 | |
277 | /* Prepare first fragment */ | |
a6ca1094 YX |
278 | skb = tipc_buf_acquire(pktmax); |
279 | if (!skb) | |
067608e9 | 280 | return -ENOMEM; |
c93d3baa | 281 | skb_orphan(skb); |
a6ca1094 YX |
282 | __skb_queue_tail(list, skb); |
283 | pktpos = skb->data; | |
284 | skb_copy_to_linear_data(skb, &pkthdr, INT_H_SIZE); | |
067608e9 JPM |
285 | pktpos += INT_H_SIZE; |
286 | pktrem -= INT_H_SIZE; | |
a6ca1094 | 287 | skb_copy_to_linear_data_offset(skb, INT_H_SIZE, mhdr, mhsz); |
067608e9 JPM |
288 | pktpos += mhsz; |
289 | pktrem -= mhsz; | |
290 | ||
291 | do { | |
292 | if (drem < pktrem) | |
293 | pktrem = drem; | |
294 | ||
f25dcc76 | 295 | if (copy_from_iter(pktpos, pktrem, &m->msg_iter) != pktrem) { |
067608e9 JPM |
296 | rc = -EFAULT; |
297 | goto error; | |
298 | } | |
299 | drem -= pktrem; | |
067608e9 JPM |
300 | |
301 | if (!drem) | |
302 | break; | |
303 | ||
304 | /* Prepare new fragment: */ | |
305 | if (drem < (pktmax - INT_H_SIZE)) | |
306 | pktsz = drem + INT_H_SIZE; | |
307 | else | |
308 | pktsz = pktmax; | |
a6ca1094 YX |
309 | skb = tipc_buf_acquire(pktsz); |
310 | if (!skb) { | |
067608e9 JPM |
311 | rc = -ENOMEM; |
312 | goto error; | |
313 | } | |
c93d3baa | 314 | skb_orphan(skb); |
a6ca1094 | 315 | __skb_queue_tail(list, skb); |
067608e9 JPM |
316 | msg_set_type(&pkthdr, FRAGMENT); |
317 | msg_set_size(&pkthdr, pktsz); | |
318 | msg_set_fragm_no(&pkthdr, ++pktno); | |
a6ca1094 YX |
319 | skb_copy_to_linear_data(skb, &pkthdr, INT_H_SIZE); |
320 | pktpos = skb->data + INT_H_SIZE; | |
067608e9 JPM |
321 | pktrem = pktsz - INT_H_SIZE; |
322 | ||
323 | } while (1); | |
a6ca1094 | 324 | msg_set_type(buf_msg(skb), LAST_FRAGMENT); |
067608e9 JPM |
325 | return dsz; |
326 | error: | |
a6ca1094 YX |
327 | __skb_queue_purge(list); |
328 | __skb_queue_head_init(list); | |
067608e9 JPM |
329 | return rc; |
330 | } | |
331 | ||
4f1688b2 JPM |
332 | /** |
333 | * tipc_msg_bundle(): Append contents of a buffer to tail of an existing one | |
05dcc5aa | 334 | * @bskb: the buffer to append to ("bundle") |
58dc55f2 | 335 | * @skb: buffer to be appended |
4f1688b2 JPM |
336 | * @mtu: max allowable size for the bundle buffer |
337 | * Consumes buffer if successful | |
338 | * Returns true if bundling could be performed, otherwise false | |
339 | */ | |
05dcc5aa | 340 | bool tipc_msg_bundle(struct sk_buff *bskb, struct sk_buff *skb, u32 mtu) |
4f1688b2 | 341 | { |
05dcc5aa | 342 | struct tipc_msg *bmsg; |
58dc55f2 | 343 | struct tipc_msg *msg = buf_msg(skb); |
05dcc5aa | 344 | unsigned int bsz; |
4f1688b2 | 345 | unsigned int msz = msg_size(msg); |
05dcc5aa | 346 | u32 start, pad; |
4f1688b2 | 347 | u32 max = mtu - INT_H_SIZE; |
4f1688b2 JPM |
348 | |
349 | if (likely(msg_user(msg) == MSG_FRAGMENTER)) | |
350 | return false; | |
05dcc5aa JPM |
351 | if (!bskb) |
352 | return false; | |
353 | bmsg = buf_msg(bskb); | |
354 | bsz = msg_size(bmsg); | |
355 | start = align(bsz); | |
356 | pad = start - bsz; | |
357 | ||
4f1688b2 JPM |
358 | if (unlikely(msg_user(msg) == CHANGEOVER_PROTOCOL)) |
359 | return false; | |
360 | if (unlikely(msg_user(msg) == BCAST_PROTOCOL)) | |
361 | return false; | |
362 | if (likely(msg_user(bmsg) != MSG_BUNDLER)) | |
363 | return false; | |
58dc55f2 | 364 | if (unlikely(skb_tailroom(bskb) < (pad + msz))) |
4f1688b2 JPM |
365 | return false; |
366 | if (unlikely(max < (start + msz))) | |
367 | return false; | |
368 | ||
58dc55f2 YX |
369 | skb_put(bskb, pad + msz); |
370 | skb_copy_to_linear_data_offset(bskb, start, skb->data, msz); | |
4f1688b2 JPM |
371 | msg_set_size(bmsg, start + msz); |
372 | msg_set_msgcnt(bmsg, msg_msgcnt(bmsg) + 1); | |
58dc55f2 | 373 | kfree_skb(skb); |
4f1688b2 JPM |
374 | return true; |
375 | } | |
376 | ||
c637c103 JPM |
377 | /** |
378 | * tipc_msg_extract(): extract bundled inner packet from buffer | |
c1336ee4 | 379 | * @skb: buffer to be extracted from. |
c637c103 | 380 | * @iskb: extracted inner buffer, to be returned |
c1336ee4 JPM |
381 | * @pos: position in outer message of msg to be extracted. |
382 | * Returns position of next msg | |
c637c103 JPM |
383 | * Consumes outer buffer when last packet extracted |
384 | * Returns true when when there is an extracted buffer, otherwise false | |
385 | */ | |
386 | bool tipc_msg_extract(struct sk_buff *skb, struct sk_buff **iskb, int *pos) | |
387 | { | |
1149557d | 388 | struct tipc_msg *msg; |
c1336ee4 | 389 | int imsz, offset; |
c637c103 | 390 | |
c1336ee4 | 391 | *iskb = NULL; |
1149557d | 392 | if (unlikely(skb_linearize(skb))) |
c1336ee4 JPM |
393 | goto none; |
394 | ||
1149557d | 395 | msg = buf_msg(skb); |
c1336ee4 JPM |
396 | offset = msg_hdr_sz(msg) + *pos; |
397 | if (unlikely(offset > (msg_size(msg) - MIN_H_SIZE))) | |
c637c103 | 398 | goto none; |
c637c103 | 399 | |
c1336ee4 JPM |
400 | *iskb = skb_clone(skb, GFP_ATOMIC); |
401 | if (unlikely(!*iskb)) | |
c637c103 | 402 | goto none; |
c1336ee4 JPM |
403 | skb_pull(*iskb, offset); |
404 | imsz = msg_size(buf_msg(*iskb)); | |
405 | skb_trim(*iskb, imsz); | |
406 | if (unlikely(!tipc_msg_validate(*iskb))) | |
c637c103 | 407 | goto none; |
c637c103 JPM |
408 | *pos += align(imsz); |
409 | return true; | |
410 | none: | |
411 | kfree_skb(skb); | |
c1336ee4 | 412 | kfree_skb(*iskb); |
c637c103 JPM |
413 | *iskb = NULL; |
414 | return false; | |
415 | } | |
416 | ||
4f1688b2 JPM |
417 | /** |
418 | * tipc_msg_make_bundle(): Create bundle buf and append message to its tail | |
58dc55f2 YX |
419 | * @list: the buffer chain |
420 | * @skb: buffer to be appended and replaced | |
421 | * @mtu: max allowable size for the bundle buffer, inclusive header | |
4f1688b2 JPM |
422 | * @dnode: destination node for message. (Not always present in header) |
423 | * Replaces buffer if successful | |
b2ad5e5f | 424 | * Returns true if success, otherwise false |
4f1688b2 | 425 | */ |
05dcc5aa | 426 | bool tipc_msg_make_bundle(struct sk_buff **skb, u32 mtu, u32 dnode) |
4f1688b2 | 427 | { |
58dc55f2 | 428 | struct sk_buff *bskb; |
4f1688b2 | 429 | struct tipc_msg *bmsg; |
05dcc5aa | 430 | struct tipc_msg *msg = buf_msg(*skb); |
4f1688b2 JPM |
431 | u32 msz = msg_size(msg); |
432 | u32 max = mtu - INT_H_SIZE; | |
433 | ||
434 | if (msg_user(msg) == MSG_FRAGMENTER) | |
435 | return false; | |
436 | if (msg_user(msg) == CHANGEOVER_PROTOCOL) | |
437 | return false; | |
438 | if (msg_user(msg) == BCAST_PROTOCOL) | |
439 | return false; | |
440 | if (msz > (max / 2)) | |
441 | return false; | |
442 | ||
58dc55f2 YX |
443 | bskb = tipc_buf_acquire(max); |
444 | if (!bskb) | |
4f1688b2 JPM |
445 | return false; |
446 | ||
58dc55f2 YX |
447 | skb_trim(bskb, INT_H_SIZE); |
448 | bmsg = buf_msg(bskb); | |
c5898636 JPM |
449 | tipc_msg_init(msg_prevnode(msg), bmsg, MSG_BUNDLER, 0, |
450 | INT_H_SIZE, dnode); | |
4f1688b2 JPM |
451 | msg_set_seqno(bmsg, msg_seqno(msg)); |
452 | msg_set_ack(bmsg, msg_ack(msg)); | |
453 | msg_set_bcast_ack(bmsg, msg_bcast_ack(msg)); | |
05dcc5aa JPM |
454 | tipc_msg_bundle(bskb, *skb, mtu); |
455 | *skb = bskb; | |
456 | return true; | |
4f1688b2 | 457 | } |
8db1bae3 JPM |
458 | |
459 | /** | |
460 | * tipc_msg_reverse(): swap source and destination addresses and add error code | |
461 | * @buf: buffer containing message to be reversed | |
462 | * @dnode: return value: node where to send message after reversal | |
463 | * @err: error code to be set in message | |
464 | * Consumes buffer if failure | |
465 | * Returns true if success, otherwise false | |
466 | */ | |
c5898636 | 467 | bool tipc_msg_reverse(u32 own_addr, struct sk_buff *buf, u32 *dnode, |
34747539 | 468 | int err) |
8db1bae3 JPM |
469 | { |
470 | struct tipc_msg *msg = buf_msg(buf); | |
8db1bae3 JPM |
471 | struct tipc_msg ohdr; |
472 | uint rdsz = min_t(uint, msg_data_sz(msg), MAX_FORWARD_SIZE); | |
473 | ||
ac0074ee | 474 | if (skb_linearize(buf)) |
8db1bae3 | 475 | goto exit; |
1149557d | 476 | msg = buf_msg(buf); |
ac0074ee JPM |
477 | if (msg_dest_droppable(msg)) |
478 | goto exit; | |
479 | if (msg_errcode(msg)) | |
8db1bae3 | 480 | goto exit; |
8db1bae3 | 481 | memcpy(&ohdr, msg, msg_hdr_sz(msg)); |
8db1bae3 JPM |
482 | msg_set_errcode(msg, err); |
483 | msg_set_origport(msg, msg_destport(&ohdr)); | |
484 | msg_set_destport(msg, msg_origport(&ohdr)); | |
c5898636 | 485 | msg_set_prevnode(msg, own_addr); |
8db1bae3 JPM |
486 | if (!msg_short(msg)) { |
487 | msg_set_orignode(msg, msg_destnode(&ohdr)); | |
488 | msg_set_destnode(msg, msg_orignode(&ohdr)); | |
489 | } | |
490 | msg_set_size(msg, msg_hdr_sz(msg) + rdsz); | |
491 | skb_trim(buf, msg_size(msg)); | |
492 | skb_orphan(buf); | |
493 | *dnode = msg_orignode(&ohdr); | |
494 | return true; | |
495 | exit: | |
496 | kfree_skb(buf); | |
e3a77561 | 497 | *dnode = 0; |
8db1bae3 JPM |
498 | return false; |
499 | } | |
5a379074 JPM |
500 | |
501 | /** | |
e3a77561 JPM |
502 | * tipc_msg_lookup_dest(): try to find new destination for named message |
503 | * @skb: the buffer containing the message. | |
504 | * @dnode: return value: next-hop node, if destination found | |
505 | * @err: return value: error code to use, if message to be rejected | |
5a379074 | 506 | * Does not consume buffer |
e3a77561 | 507 | * Returns true if a destination is found, false otherwise |
5a379074 | 508 | */ |
e3a77561 JPM |
509 | bool tipc_msg_lookup_dest(struct net *net, struct sk_buff *skb, |
510 | u32 *dnode, int *err) | |
5a379074 | 511 | { |
e3a77561 | 512 | struct tipc_msg *msg = buf_msg(skb); |
5a379074 | 513 | u32 dport; |
d482994f | 514 | u32 own_addr = tipc_own_addr(net); |
5a379074 | 515 | |
e3a77561 JPM |
516 | if (!msg_isdata(msg)) |
517 | return false; | |
518 | if (!msg_named(msg)) | |
519 | return false; | |
d482994f JPM |
520 | if (msg_errcode(msg)) |
521 | return false; | |
e3a77561 JPM |
522 | *err = -TIPC_ERR_NO_NAME; |
523 | if (skb_linearize(skb)) | |
524 | return false; | |
d482994f | 525 | if (msg_reroute_cnt(msg)) |
e3a77561 | 526 | return false; |
34747539 | 527 | *dnode = addr_domain(net, msg_lookup_scope(msg)); |
4ac1c8d0 | 528 | dport = tipc_nametbl_translate(net, msg_nametype(msg), |
e3a77561 | 529 | msg_nameinst(msg), dnode); |
5a379074 | 530 | if (!dport) |
e3a77561 | 531 | return false; |
5a379074 | 532 | msg_incr_reroute_cnt(msg); |
d482994f JPM |
533 | if (*dnode != own_addr) |
534 | msg_set_prevnode(msg, own_addr); | |
5a379074 JPM |
535 | msg_set_destnode(msg, *dnode); |
536 | msg_set_destport(msg, dport); | |
e3a77561 JPM |
537 | *err = TIPC_OK; |
538 | return true; | |
5a379074 | 539 | } |
078bec82 JPM |
540 | |
541 | /* tipc_msg_reassemble() - clone a buffer chain of fragments and | |
542 | * reassemble the clones into one message | |
543 | */ | |
a6ca1094 | 544 | struct sk_buff *tipc_msg_reassemble(struct sk_buff_head *list) |
078bec82 | 545 | { |
a6ca1094 YX |
546 | struct sk_buff *skb; |
547 | struct sk_buff *frag = NULL; | |
078bec82 JPM |
548 | struct sk_buff *head = NULL; |
549 | int hdr_sz; | |
550 | ||
551 | /* Copy header if single buffer */ | |
a6ca1094 YX |
552 | if (skb_queue_len(list) == 1) { |
553 | skb = skb_peek(list); | |
554 | hdr_sz = skb_headroom(skb) + msg_hdr_sz(buf_msg(skb)); | |
555 | return __pskb_copy(skb, hdr_sz, GFP_ATOMIC); | |
078bec82 JPM |
556 | } |
557 | ||
558 | /* Clone all fragments and reassemble */ | |
a6ca1094 YX |
559 | skb_queue_walk(list, skb) { |
560 | frag = skb_clone(skb, GFP_ATOMIC); | |
078bec82 JPM |
561 | if (!frag) |
562 | goto error; | |
563 | frag->next = NULL; | |
564 | if (tipc_buf_append(&head, &frag)) | |
565 | break; | |
566 | if (!head) | |
567 | goto error; | |
078bec82 JPM |
568 | } |
569 | return frag; | |
570 | error: | |
571 | pr_warn("Failed do clone local mcast rcv buffer\n"); | |
572 | kfree_skb(head); | |
573 | return NULL; | |
574 | } |