blob: 9682296f5e7cea595ed981fdcae15f378708c50a [file] [log] [blame]
Per Lidenb97bf3f2006-01-02 19:04:38 +01001/*
2 * net/tipc/msg.c: TIPC message header routines
YOSHIFUJI Hideakic4307282007-02-09 23:25:21 +09003 *
Jon Paul Maloy37e22162014-05-14 05:39:12 -04004 * Copyright (c) 2000-2006, 2014, Ericsson AB
Allan Stephens741de3e2011-01-25 13:33:31 -05005 * Copyright (c) 2005, 2010-2011, Wind River Systems
Per Lidenb97bf3f2006-01-02 19:04:38 +01006 * All rights reserved.
7 *
Per Liden9ea1fd32006-01-11 13:30:43 +01008 * Redistribution and use in source and binary forms, with or without
Per Lidenb97bf3f2006-01-02 19:04:38 +01009 * modification, are permitted provided that the following conditions are met:
10 *
Per Liden9ea1fd32006-01-11 13:30:43 +010011 * 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.
Per Lidenb97bf3f2006-01-02 19:04:38 +010019 *
Per Liden9ea1fd32006-01-11 13:30:43 +010020 * 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
Per Lidenb97bf3f2006-01-02 19:04:38 +010034 * POSSIBILITY OF SUCH DAMAGE.
35 */
36
37#include "core.h"
Per Lidenb97bf3f2006-01-02 19:04:38 +010038#include "msg.h"
Jon Paul Maloy5a379072014-06-25 20:41:36 -050039#include "addr.h"
40#include "name_table.h"
Per Lidenb97bf3f2006-01-02 19:04:38 +010041
Jon Paul Maloy8db1bae2014-06-25 20:41:35 -050042#define MAX_FORWARD_SIZE 1024
43
Jon Paul Maloy4f1688b2014-06-25 20:41:32 -050044static unsigned int align(unsigned int i)
Allan Stephens23461e82010-05-11 14:30:18 +000045{
Jon Paul Maloy4f1688b2014-06-25 20:41:32 -050046 return (i + 3) & ~3u;
Allan Stephens23461e82010-05-11 14:30:18 +000047}
48
Paul Gortmakerae8509c2013-06-17 10:54:47 -040049void tipc_msg_init(struct tipc_msg *m, u32 user, u32 type, u32 hsize,
50 u32 destnode)
Allan Stephens23461e82010-05-11 14:30:18 +000051{
52 memset(m, 0, hsize);
53 msg_set_version(m);
54 msg_set_user(m, user);
55 msg_set_hdr_sz(m, hsize);
56 msg_set_size(m, hsize);
57 msg_set_prevnode(m, tipc_own_addr);
58 msg_set_type(m, type);
Allan Stephens15f4e2b2011-05-31 14:35:18 -040059 msg_set_orignode(m, tipc_own_addr);
60 msg_set_destnode(m, destnode);
Allan Stephens23461e82010-05-11 14:30:18 +000061}
62
63/**
Allan Stephens23461e82010-05-11 14:30:18 +000064 * tipc_msg_build - create message using specified header and data
65 *
66 * Note: Caller must not hold any locks in case copy_from_user() is interrupted!
67 *
68 * Returns message data size or errno
69 */
Allan Stephens26896902011-04-21 10:42:07 -050070int tipc_msg_build(struct tipc_msg *hdr, struct iovec const *msg_sect,
Ying Xue9446b872013-10-18 07:23:15 +020071 unsigned int len, int max_size, struct sk_buff **buf)
Allan Stephens23461e82010-05-11 14:30:18 +000072{
Ying Xue5c0a0fc2013-10-18 07:23:14 +020073 int dsz, sz, hsz;
74 unsigned char *to;
Allan Stephens23461e82010-05-11 14:30:18 +000075
Ying Xue9446b872013-10-18 07:23:15 +020076 dsz = len;
Ying Xue5c0a0fc2013-10-18 07:23:14 +020077 hsz = msg_hdr_sz(hdr);
Allan Stephens23461e82010-05-11 14:30:18 +000078 sz = hsz + dsz;
79 msg_set_size(hdr, sz);
80 if (unlikely(sz > max_size)) {
81 *buf = NULL;
82 return dsz;
83 }
84
stephen hemminger31e3c3f2010-10-13 13:20:35 +000085 *buf = tipc_buf_acquire(sz);
Allan Stephens23461e82010-05-11 14:30:18 +000086 if (!(*buf))
87 return -ENOMEM;
88 skb_copy_to_linear_data(*buf, hdr, hsz);
Ying Xue5c0a0fc2013-10-18 07:23:14 +020089 to = (*buf)->data + hsz;
Ying Xue9446b872013-10-18 07:23:15 +020090 if (len && memcpy_fromiovecend(to, msg_sect, 0, dsz)) {
Ying Xue5c0a0fc2013-10-18 07:23:14 +020091 kfree_skb(*buf);
92 *buf = NULL;
93 return -EFAULT;
Allan Stephens23461e82010-05-11 14:30:18 +000094 }
Ying Xue5c0a0fc2013-10-18 07:23:14 +020095 return dsz;
Allan Stephens23461e82010-05-11 14:30:18 +000096}
Jon Paul Maloy37e22162014-05-14 05:39:12 -040097
98/* tipc_buf_append(): Append a buffer to the fragment list of another buffer
Jon Paul Maloy29322d0d2014-07-05 13:44:13 -040099 * @*headbuf: in: NULL for first frag, otherwise value returned from prev call
100 * out: set when successful non-complete reassembly, otherwise NULL
101 * @*buf: in: the buffer to append. Always defined
102 * out: head buf after sucessful complete reassembly, otherwise NULL
103 * Returns 1 when reassembly complete, otherwise 0
Jon Paul Maloy37e22162014-05-14 05:39:12 -0400104 */
105int tipc_buf_append(struct sk_buff **headbuf, struct sk_buff **buf)
106{
107 struct sk_buff *head = *headbuf;
108 struct sk_buff *frag = *buf;
109 struct sk_buff *tail;
110 struct tipc_msg *msg = buf_msg(frag);
111 u32 fragid = msg_type(msg);
112 bool headstolen;
113 int delta;
114
115 skb_pull(frag, msg_hdr_sz(msg));
116
117 if (fragid == FIRST_FRAGMENT) {
118 if (head || skb_unclone(frag, GFP_ATOMIC))
119 goto out_free;
120 head = *headbuf = frag;
121 skb_frag_list_init(head);
Jon Paul Maloy29322d0d2014-07-05 13:44:13 -0400122 *buf = NULL;
Jon Paul Maloy37e22162014-05-14 05:39:12 -0400123 return 0;
124 }
125 if (!head)
126 goto out_free;
127 tail = TIPC_SKB_CB(head)->tail;
128 if (skb_try_coalesce(head, frag, &headstolen, &delta)) {
129 kfree_skb_partial(frag, headstolen);
130 } else {
131 if (!skb_has_frag_list(head))
132 skb_shinfo(head)->frag_list = frag;
133 else
134 tail->next = frag;
135 head->truesize += frag->truesize;
136 head->data_len += frag->len;
137 head->len += frag->len;
138 TIPC_SKB_CB(head)->tail = frag;
139 }
140 if (fragid == LAST_FRAGMENT) {
141 *buf = head;
142 TIPC_SKB_CB(head)->tail = NULL;
143 *headbuf = NULL;
144 return 1;
145 }
146 *buf = NULL;
147 return 0;
148out_free:
149 pr_warn_ratelimited("Unable to build fragment list\n");
150 kfree_skb(*buf);
Jon Paul Maloy29322d0d2014-07-05 13:44:13 -0400151 kfree_skb(*headbuf);
152 *buf = *headbuf = NULL;
Jon Paul Maloy37e22162014-05-14 05:39:12 -0400153 return 0;
154}
Jon Paul Maloy4f1688b2014-06-25 20:41:32 -0500155
Jon Paul Maloy067608e2014-06-25 20:41:34 -0500156
157/**
158 * tipc_msg_build2 - create buffer chain containing specified header and data
159 * @mhdr: Message header, to be prepended to data
160 * @iov: User data
161 * @offset: Posision in iov to start copying from
162 * @dsz: Total length of user data
163 * @pktmax: Max packet size that can be used
164 * @chain: Buffer or chain of buffers to be returned to caller
165 * Returns message data size or errno: -ENOMEM, -EFAULT
166 */
167int tipc_msg_build2(struct tipc_msg *mhdr, struct iovec const *iov,
168 int offset, int dsz, int pktmax , struct sk_buff **chain)
169{
170 int mhsz = msg_hdr_sz(mhdr);
171 int msz = mhsz + dsz;
172 int pktno = 1;
173 int pktsz;
174 int pktrem = pktmax;
175 int drem = dsz;
176 struct tipc_msg pkthdr;
177 struct sk_buff *buf, *prev;
178 char *pktpos;
179 int rc;
180
181 msg_set_size(mhdr, msz);
182
183 /* No fragmentation needed? */
184 if (likely(msz <= pktmax)) {
185 buf = tipc_buf_acquire(msz);
186 *chain = buf;
187 if (unlikely(!buf))
188 return -ENOMEM;
189 skb_copy_to_linear_data(buf, mhdr, mhsz);
190 pktpos = buf->data + mhsz;
191 if (!dsz || !memcpy_fromiovecend(pktpos, iov, offset, dsz))
192 return dsz;
193 rc = -EFAULT;
194 goto error;
195 }
196
197 /* Prepare reusable fragment header */
198 tipc_msg_init(&pkthdr, MSG_FRAGMENTER, FIRST_FRAGMENT,
199 INT_H_SIZE, msg_destnode(mhdr));
200 msg_set_size(&pkthdr, pktmax);
201 msg_set_fragm_no(&pkthdr, pktno);
202
203 /* Prepare first fragment */
204 *chain = buf = tipc_buf_acquire(pktmax);
205 if (!buf)
206 return -ENOMEM;
207 pktpos = buf->data;
208 skb_copy_to_linear_data(buf, &pkthdr, INT_H_SIZE);
209 pktpos += INT_H_SIZE;
210 pktrem -= INT_H_SIZE;
211 skb_copy_to_linear_data_offset(buf, INT_H_SIZE, mhdr, mhsz);
212 pktpos += mhsz;
213 pktrem -= mhsz;
214
215 do {
216 if (drem < pktrem)
217 pktrem = drem;
218
219 if (memcpy_fromiovecend(pktpos, iov, offset, pktrem)) {
220 rc = -EFAULT;
221 goto error;
222 }
223 drem -= pktrem;
224 offset += pktrem;
225
226 if (!drem)
227 break;
228
229 /* Prepare new fragment: */
230 if (drem < (pktmax - INT_H_SIZE))
231 pktsz = drem + INT_H_SIZE;
232 else
233 pktsz = pktmax;
234 prev = buf;
235 buf = tipc_buf_acquire(pktsz);
236 if (!buf) {
237 rc = -ENOMEM;
238 goto error;
239 }
240 prev->next = buf;
241 msg_set_type(&pkthdr, FRAGMENT);
242 msg_set_size(&pkthdr, pktsz);
243 msg_set_fragm_no(&pkthdr, ++pktno);
244 skb_copy_to_linear_data(buf, &pkthdr, INT_H_SIZE);
245 pktpos = buf->data + INT_H_SIZE;
246 pktrem = pktsz - INT_H_SIZE;
247
248 } while (1);
249
250 msg_set_type(buf_msg(buf), LAST_FRAGMENT);
251 return dsz;
252error:
253 kfree_skb_list(*chain);
254 *chain = NULL;
255 return rc;
256}
257
Jon Paul Maloy4f1688b2014-06-25 20:41:32 -0500258/**
259 * tipc_msg_bundle(): Append contents of a buffer to tail of an existing one
260 * @bbuf: the existing buffer ("bundle")
261 * @buf: buffer to be appended
262 * @mtu: max allowable size for the bundle buffer
263 * Consumes buffer if successful
264 * Returns true if bundling could be performed, otherwise false
265 */
266bool tipc_msg_bundle(struct sk_buff *bbuf, struct sk_buff *buf, u32 mtu)
267{
268 struct tipc_msg *bmsg = buf_msg(bbuf);
269 struct tipc_msg *msg = buf_msg(buf);
270 unsigned int bsz = msg_size(bmsg);
271 unsigned int msz = msg_size(msg);
272 u32 start = align(bsz);
273 u32 max = mtu - INT_H_SIZE;
274 u32 pad = start - bsz;
275
276 if (likely(msg_user(msg) == MSG_FRAGMENTER))
277 return false;
278 if (unlikely(msg_user(msg) == CHANGEOVER_PROTOCOL))
279 return false;
280 if (unlikely(msg_user(msg) == BCAST_PROTOCOL))
281 return false;
282 if (likely(msg_user(bmsg) != MSG_BUNDLER))
283 return false;
284 if (likely(msg_type(bmsg) != BUNDLE_OPEN))
285 return false;
286 if (unlikely(skb_tailroom(bbuf) < (pad + msz)))
287 return false;
288 if (unlikely(max < (start + msz)))
289 return false;
290
291 skb_put(bbuf, pad + msz);
292 skb_copy_to_linear_data_offset(bbuf, start, buf->data, msz);
293 msg_set_size(bmsg, start + msz);
294 msg_set_msgcnt(bmsg, msg_msgcnt(bmsg) + 1);
295 bbuf->next = buf->next;
296 kfree_skb(buf);
297 return true;
298}
299
300/**
301 * tipc_msg_make_bundle(): Create bundle buf and append message to its tail
302 * @buf: buffer to be appended and replaced
303 * @mtu: max allowable size for the bundle buffer, inclusive header
304 * @dnode: destination node for message. (Not always present in header)
305 * Replaces buffer if successful
306 * Returns true if sucess, otherwise false
307 */
308bool tipc_msg_make_bundle(struct sk_buff **buf, u32 mtu, u32 dnode)
309{
310 struct sk_buff *bbuf;
311 struct tipc_msg *bmsg;
312 struct tipc_msg *msg = buf_msg(*buf);
313 u32 msz = msg_size(msg);
314 u32 max = mtu - INT_H_SIZE;
315
316 if (msg_user(msg) == MSG_FRAGMENTER)
317 return false;
318 if (msg_user(msg) == CHANGEOVER_PROTOCOL)
319 return false;
320 if (msg_user(msg) == BCAST_PROTOCOL)
321 return false;
322 if (msz > (max / 2))
323 return false;
324
325 bbuf = tipc_buf_acquire(max);
326 if (!bbuf)
327 return false;
328
329 skb_trim(bbuf, INT_H_SIZE);
330 bmsg = buf_msg(bbuf);
331 tipc_msg_init(bmsg, MSG_BUNDLER, BUNDLE_OPEN, INT_H_SIZE, dnode);
332 msg_set_seqno(bmsg, msg_seqno(msg));
333 msg_set_ack(bmsg, msg_ack(msg));
334 msg_set_bcast_ack(bmsg, msg_bcast_ack(msg));
335 bbuf->next = (*buf)->next;
336 tipc_msg_bundle(bbuf, *buf, mtu);
337 *buf = bbuf;
338 return true;
339}
Jon Paul Maloy8db1bae2014-06-25 20:41:35 -0500340
341/**
342 * tipc_msg_reverse(): swap source and destination addresses and add error code
343 * @buf: buffer containing message to be reversed
344 * @dnode: return value: node where to send message after reversal
345 * @err: error code to be set in message
346 * Consumes buffer if failure
347 * Returns true if success, otherwise false
348 */
349bool tipc_msg_reverse(struct sk_buff *buf, u32 *dnode, int err)
350{
351 struct tipc_msg *msg = buf_msg(buf);
352 uint imp = msg_importance(msg);
353 struct tipc_msg ohdr;
354 uint rdsz = min_t(uint, msg_data_sz(msg), MAX_FORWARD_SIZE);
355
Jon Paul Maloyac0074e2014-06-25 20:41:41 -0500356 if (skb_linearize(buf))
Jon Paul Maloy8db1bae2014-06-25 20:41:35 -0500357 goto exit;
Jon Paul Maloyac0074e2014-06-25 20:41:41 -0500358 if (msg_dest_droppable(msg))
359 goto exit;
360 if (msg_errcode(msg))
Jon Paul Maloy8db1bae2014-06-25 20:41:35 -0500361 goto exit;
362
363 memcpy(&ohdr, msg, msg_hdr_sz(msg));
Jon Paul Maloyac0074e2014-06-25 20:41:41 -0500364 imp = min_t(uint, imp + 1, TIPC_CRITICAL_IMPORTANCE);
365 if (msg_isdata(msg))
366 msg_set_importance(msg, imp);
Jon Paul Maloy8db1bae2014-06-25 20:41:35 -0500367 msg_set_errcode(msg, err);
368 msg_set_origport(msg, msg_destport(&ohdr));
369 msg_set_destport(msg, msg_origport(&ohdr));
370 msg_set_prevnode(msg, tipc_own_addr);
371 if (!msg_short(msg)) {
372 msg_set_orignode(msg, msg_destnode(&ohdr));
373 msg_set_destnode(msg, msg_orignode(&ohdr));
374 }
375 msg_set_size(msg, msg_hdr_sz(msg) + rdsz);
376 skb_trim(buf, msg_size(msg));
377 skb_orphan(buf);
378 *dnode = msg_orignode(&ohdr);
379 return true;
380exit:
381 kfree_skb(buf);
382 return false;
383}
Jon Paul Maloy5a379072014-06-25 20:41:36 -0500384
385/**
386 * tipc_msg_eval: determine fate of message that found no destination
387 * @buf: the buffer containing the message.
388 * @dnode: return value: next-hop node, if message to be forwarded
389 * @err: error code to use, if message to be rejected
390 *
391 * Does not consume buffer
392 * Returns 0 (TIPC_OK) if message ok and we can try again, -TIPC error
393 * code if message to be rejected
394 */
395int tipc_msg_eval(struct sk_buff *buf, u32 *dnode)
396{
397 struct tipc_msg *msg = buf_msg(buf);
398 u32 dport;
399
400 if (msg_type(msg) != TIPC_NAMED_MSG)
401 return -TIPC_ERR_NO_PORT;
402 if (skb_linearize(buf))
403 return -TIPC_ERR_NO_NAME;
404 if (msg_data_sz(msg) > MAX_FORWARD_SIZE)
405 return -TIPC_ERR_NO_NAME;
406 if (msg_reroute_cnt(msg) > 0)
407 return -TIPC_ERR_NO_NAME;
408
409 *dnode = addr_domain(msg_lookup_scope(msg));
410 dport = tipc_nametbl_translate(msg_nametype(msg),
411 msg_nameinst(msg),
412 dnode);
413 if (!dport)
414 return -TIPC_ERR_NO_NAME;
415 msg_incr_reroute_cnt(msg);
416 msg_set_destnode(msg, *dnode);
417 msg_set_destport(msg, dport);
418 return TIPC_OK;
419}
Jon Paul Maloy078bec82014-07-16 20:41:00 -0400420
421/* tipc_msg_reassemble() - clone a buffer chain of fragments and
422 * reassemble the clones into one message
423 */
424struct sk_buff *tipc_msg_reassemble(struct sk_buff *chain)
425{
426 struct sk_buff *buf = chain;
427 struct sk_buff *frag = buf;
428 struct sk_buff *head = NULL;
429 int hdr_sz;
430
431 /* Copy header if single buffer */
432 if (!buf->next) {
433 hdr_sz = skb_headroom(buf) + msg_hdr_sz(buf_msg(buf));
434 return __pskb_copy(buf, hdr_sz, GFP_ATOMIC);
435 }
436
437 /* Clone all fragments and reassemble */
438 while (buf) {
439 frag = skb_clone(buf, GFP_ATOMIC);
440 if (!frag)
441 goto error;
442 frag->next = NULL;
443 if (tipc_buf_append(&head, &frag))
444 break;
445 if (!head)
446 goto error;
447 buf = buf->next;
448 }
449 return frag;
450error:
451 pr_warn("Failed do clone local mcast rcv buffer\n");
452 kfree_skb(head);
453 return NULL;
454}