xref: /linux/net/sctp/stream.c (revision 564f7dfde24a405d877168f150ae5d29d3ad99c7)
1 /* SCTP kernel implementation
2  * (C) Copyright IBM Corp. 2001, 2004
3  * Copyright (c) 1999-2000 Cisco, Inc.
4  * Copyright (c) 1999-2001 Motorola, Inc.
5  * Copyright (c) 2001 Intel Corp.
6  *
7  * This file is part of the SCTP kernel implementation
8  *
9  * These functions manipulate sctp tsn mapping array.
10  *
11  * This SCTP implementation is free software;
12  * you can redistribute it and/or modify it under the terms of
13  * the GNU General Public License as published by
14  * the Free Software Foundation; either version 2, or (at your option)
15  * any later version.
16  *
17  * This SCTP implementation is distributed in the hope that it
18  * will be useful, but WITHOUT ANY WARRANTY; without even the implied
19  *                 ************************
20  * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
21  * See the GNU General Public License for more details.
22  *
23  * You should have received a copy of the GNU General Public License
24  * along with GNU CC; see the file COPYING.  If not, see
25  * <http://www.gnu.org/licenses/>.
26  *
27  * Please send any bug reports or fixes you make to the
28  * email address(es):
29  *    lksctp developers <linux-sctp@vger.kernel.org>
30  *
31  * Written or modified by:
32  *    Xin Long <lucien.xin@gmail.com>
33  */
34 
35 #include <net/sctp/sctp.h>
36 #include <net/sctp/sm.h>
37 
38 int sctp_stream_new(struct sctp_association *asoc, gfp_t gfp)
39 {
40 	struct sctp_stream *stream;
41 	int i;
42 
43 	stream = kzalloc(sizeof(*stream), gfp);
44 	if (!stream)
45 		return -ENOMEM;
46 
47 	stream->outcnt = asoc->c.sinit_num_ostreams;
48 	stream->out = kcalloc(stream->outcnt, sizeof(*stream->out), gfp);
49 	if (!stream->out) {
50 		kfree(stream);
51 		return -ENOMEM;
52 	}
53 	for (i = 0; i < stream->outcnt; i++)
54 		stream->out[i].state = SCTP_STREAM_OPEN;
55 
56 	asoc->stream = stream;
57 
58 	return 0;
59 }
60 
61 int sctp_stream_init(struct sctp_association *asoc, gfp_t gfp)
62 {
63 	struct sctp_stream *stream = asoc->stream;
64 	int i;
65 
66 	/* Initial stream->out size may be very big, so free it and alloc
67 	 * a new one with new outcnt to save memory.
68 	 */
69 	kfree(stream->out);
70 	stream->outcnt = asoc->c.sinit_num_ostreams;
71 	stream->out = kcalloc(stream->outcnt, sizeof(*stream->out), gfp);
72 	if (!stream->out)
73 		goto nomem;
74 
75 	for (i = 0; i < stream->outcnt; i++)
76 		stream->out[i].state = SCTP_STREAM_OPEN;
77 
78 	stream->incnt = asoc->c.sinit_max_instreams;
79 	stream->in = kcalloc(stream->incnt, sizeof(*stream->in), gfp);
80 	if (!stream->in) {
81 		kfree(stream->out);
82 		goto nomem;
83 	}
84 
85 	return 0;
86 
87 nomem:
88 	asoc->stream = NULL;
89 	kfree(stream);
90 
91 	return -ENOMEM;
92 }
93 
94 void sctp_stream_free(struct sctp_stream *stream)
95 {
96 	if (unlikely(!stream))
97 		return;
98 
99 	kfree(stream->out);
100 	kfree(stream->in);
101 	kfree(stream);
102 }
103 
104 void sctp_stream_clear(struct sctp_stream *stream)
105 {
106 	int i;
107 
108 	for (i = 0; i < stream->outcnt; i++)
109 		stream->out[i].ssn = 0;
110 
111 	for (i = 0; i < stream->incnt; i++)
112 		stream->in[i].ssn = 0;
113 }
114 
115 static int sctp_send_reconf(struct sctp_association *asoc,
116 			    struct sctp_chunk *chunk)
117 {
118 	struct net *net = sock_net(asoc->base.sk);
119 	int retval = 0;
120 
121 	retval = sctp_primitive_RECONF(net, asoc, chunk);
122 	if (retval)
123 		sctp_chunk_free(chunk);
124 
125 	return retval;
126 }
127 
128 int sctp_send_reset_streams(struct sctp_association *asoc,
129 			    struct sctp_reset_streams *params)
130 {
131 	struct sctp_stream *stream = asoc->stream;
132 	__u16 i, str_nums, *str_list;
133 	struct sctp_chunk *chunk;
134 	int retval = -EINVAL;
135 	bool out, in;
136 
137 	if (!asoc->peer.reconf_capable ||
138 	    !(asoc->strreset_enable & SCTP_ENABLE_RESET_STREAM_REQ)) {
139 		retval = -ENOPROTOOPT;
140 		goto out;
141 	}
142 
143 	if (asoc->strreset_outstanding) {
144 		retval = -EINPROGRESS;
145 		goto out;
146 	}
147 
148 	out = params->srs_flags & SCTP_STREAM_RESET_OUTGOING;
149 	in  = params->srs_flags & SCTP_STREAM_RESET_INCOMING;
150 	if (!out && !in)
151 		goto out;
152 
153 	str_nums = params->srs_number_streams;
154 	str_list = params->srs_stream_list;
155 	if (out && str_nums)
156 		for (i = 0; i < str_nums; i++)
157 			if (str_list[i] >= stream->outcnt)
158 				goto out;
159 
160 	if (in && str_nums)
161 		for (i = 0; i < str_nums; i++)
162 			if (str_list[i] >= stream->incnt)
163 				goto out;
164 
165 	for (i = 0; i < str_nums; i++)
166 		str_list[i] = htons(str_list[i]);
167 
168 	chunk = sctp_make_strreset_req(asoc, str_nums, str_list, out, in);
169 
170 	for (i = 0; i < str_nums; i++)
171 		str_list[i] = ntohs(str_list[i]);
172 
173 	if (!chunk) {
174 		retval = -ENOMEM;
175 		goto out;
176 	}
177 
178 	if (out) {
179 		if (str_nums)
180 			for (i = 0; i < str_nums; i++)
181 				stream->out[str_list[i]].state =
182 						       SCTP_STREAM_CLOSED;
183 		else
184 			for (i = 0; i < stream->outcnt; i++)
185 				stream->out[i].state = SCTP_STREAM_CLOSED;
186 	}
187 
188 	asoc->strreset_chunk = chunk;
189 	sctp_chunk_hold(asoc->strreset_chunk);
190 
191 	retval = sctp_send_reconf(asoc, chunk);
192 	if (retval) {
193 		sctp_chunk_put(asoc->strreset_chunk);
194 		asoc->strreset_chunk = NULL;
195 		if (!out)
196 			goto out;
197 
198 		if (str_nums)
199 			for (i = 0; i < str_nums; i++)
200 				stream->out[str_list[i]].state =
201 						       SCTP_STREAM_OPEN;
202 		else
203 			for (i = 0; i < stream->outcnt; i++)
204 				stream->out[i].state = SCTP_STREAM_OPEN;
205 
206 		goto out;
207 	}
208 
209 	asoc->strreset_outstanding = out + in;
210 
211 out:
212 	return retval;
213 }
214 
215 int sctp_send_reset_assoc(struct sctp_association *asoc)
216 {
217 	struct sctp_chunk *chunk = NULL;
218 	int retval;
219 	__u16 i;
220 
221 	if (!asoc->peer.reconf_capable ||
222 	    !(asoc->strreset_enable & SCTP_ENABLE_RESET_ASSOC_REQ))
223 		return -ENOPROTOOPT;
224 
225 	if (asoc->strreset_outstanding)
226 		return -EINPROGRESS;
227 
228 	chunk = sctp_make_strreset_tsnreq(asoc);
229 	if (!chunk)
230 		return -ENOMEM;
231 
232 	/* Block further xmit of data until this request is completed */
233 	for (i = 0; i < asoc->stream->outcnt; i++)
234 		asoc->stream->out[i].state = SCTP_STREAM_CLOSED;
235 
236 	asoc->strreset_chunk = chunk;
237 	sctp_chunk_hold(asoc->strreset_chunk);
238 
239 	retval = sctp_send_reconf(asoc, chunk);
240 	if (retval) {
241 		sctp_chunk_put(asoc->strreset_chunk);
242 		asoc->strreset_chunk = NULL;
243 
244 		for (i = 0; i < asoc->stream->outcnt; i++)
245 			asoc->stream->out[i].state = SCTP_STREAM_OPEN;
246 
247 		return retval;
248 	}
249 
250 	asoc->strreset_outstanding = 1;
251 
252 	return 0;
253 }
254 
255 int sctp_send_add_streams(struct sctp_association *asoc,
256 			  struct sctp_add_streams *params)
257 {
258 	struct sctp_stream *stream = asoc->stream;
259 	struct sctp_chunk *chunk = NULL;
260 	int retval = -ENOMEM;
261 	__u32 outcnt, incnt;
262 	__u16 out, in;
263 
264 	if (!asoc->peer.reconf_capable ||
265 	    !(asoc->strreset_enable & SCTP_ENABLE_CHANGE_ASSOC_REQ)) {
266 		retval = -ENOPROTOOPT;
267 		goto out;
268 	}
269 
270 	if (asoc->strreset_outstanding) {
271 		retval = -EINPROGRESS;
272 		goto out;
273 	}
274 
275 	out = params->sas_outstrms;
276 	in  = params->sas_instrms;
277 	outcnt = stream->outcnt + out;
278 	incnt = stream->incnt + in;
279 	if (outcnt > SCTP_MAX_STREAM || incnt > SCTP_MAX_STREAM ||
280 	    (!out && !in)) {
281 		retval = -EINVAL;
282 		goto out;
283 	}
284 
285 	if (out) {
286 		struct sctp_stream_out *streamout;
287 
288 		streamout = krealloc(stream->out, outcnt * sizeof(*streamout),
289 				     GFP_KERNEL);
290 		if (!streamout)
291 			goto out;
292 
293 		memset(streamout + stream->outcnt, 0, out * sizeof(*streamout));
294 		stream->out = streamout;
295 	}
296 
297 	if (in) {
298 		struct sctp_stream_in *streamin;
299 
300 		streamin = krealloc(stream->in, incnt * sizeof(*streamin),
301 				    GFP_KERNEL);
302 		if (!streamin)
303 			goto out;
304 
305 		memset(streamin + stream->incnt, 0, in * sizeof(*streamin));
306 		stream->in = streamin;
307 	}
308 
309 	chunk = sctp_make_strreset_addstrm(asoc, out, in);
310 	if (!chunk)
311 		goto out;
312 
313 	asoc->strreset_chunk = chunk;
314 	sctp_chunk_hold(asoc->strreset_chunk);
315 
316 	retval = sctp_send_reconf(asoc, chunk);
317 	if (retval) {
318 		sctp_chunk_put(asoc->strreset_chunk);
319 		asoc->strreset_chunk = NULL;
320 		goto out;
321 	}
322 
323 	stream->incnt = incnt;
324 	stream->outcnt = outcnt;
325 
326 	asoc->strreset_outstanding = !!out + !!in;
327 
328 out:
329 	return retval;
330 }
331 
332 static sctp_paramhdr_t *sctp_chunk_lookup_strreset_param(
333 			struct sctp_association *asoc, __u32 resp_seq)
334 {
335 	struct sctp_chunk *chunk = asoc->strreset_chunk;
336 	struct sctp_reconf_chunk *hdr;
337 	union sctp_params param;
338 
339 	if (ntohl(resp_seq) != asoc->strreset_outseq || !chunk)
340 		return NULL;
341 
342 	hdr = (struct sctp_reconf_chunk *)chunk->chunk_hdr;
343 	sctp_walk_params(param, hdr, params) {
344 		/* sctp_strreset_tsnreq is actually the basic structure
345 		 * of all stream reconf params, so it's safe to use it
346 		 * to access request_seq.
347 		 */
348 		struct sctp_strreset_tsnreq *req = param.v;
349 
350 		if (req->request_seq == resp_seq)
351 			return param.v;
352 	}
353 
354 	return NULL;
355 }
356 
357 struct sctp_chunk *sctp_process_strreset_outreq(
358 				struct sctp_association *asoc,
359 				union sctp_params param,
360 				struct sctp_ulpevent **evp)
361 {
362 	struct sctp_strreset_outreq *outreq = param.v;
363 	struct sctp_stream *stream = asoc->stream;
364 	__u16 i, nums, flags = 0, *str_p = NULL;
365 	__u32 result = SCTP_STRRESET_DENIED;
366 	__u32 request_seq;
367 
368 	request_seq = ntohl(outreq->request_seq);
369 
370 	if (ntohl(outreq->send_reset_at_tsn) >
371 	    sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map)) {
372 		result = SCTP_STRRESET_IN_PROGRESS;
373 		goto out;
374 	}
375 
376 	if (request_seq > asoc->strreset_inseq) {
377 		result = SCTP_STRRESET_ERR_BAD_SEQNO;
378 		goto out;
379 	} else if (request_seq == asoc->strreset_inseq) {
380 		asoc->strreset_inseq++;
381 	}
382 
383 	/* Check strreset_enable after inseq inc, as sender cannot tell
384 	 * the peer doesn't enable strreset after receiving response with
385 	 * result denied, as well as to keep consistent with bsd.
386 	 */
387 	if (!(asoc->strreset_enable & SCTP_ENABLE_RESET_STREAM_REQ))
388 		goto out;
389 
390 	if (asoc->strreset_chunk) {
391 		sctp_paramhdr_t *param_hdr;
392 		struct sctp_transport *t;
393 
394 		param_hdr = sctp_chunk_lookup_strreset_param(
395 					asoc, outreq->response_seq);
396 		if (!param_hdr || param_hdr->type !=
397 					SCTP_PARAM_RESET_IN_REQUEST) {
398 			/* same process with outstanding isn't 0 */
399 			result = SCTP_STRRESET_ERR_IN_PROGRESS;
400 			goto out;
401 		}
402 
403 		asoc->strreset_outstanding--;
404 		asoc->strreset_outseq++;
405 
406 		if (!asoc->strreset_outstanding) {
407 			t = asoc->strreset_chunk->transport;
408 			if (del_timer(&t->reconf_timer))
409 				sctp_transport_put(t);
410 
411 			sctp_chunk_put(asoc->strreset_chunk);
412 			asoc->strreset_chunk = NULL;
413 		}
414 
415 		flags = SCTP_STREAM_RESET_INCOMING_SSN;
416 	}
417 
418 	nums = (ntohs(param.p->length) - sizeof(*outreq)) / 2;
419 	if (nums) {
420 		str_p = outreq->list_of_streams;
421 		for (i = 0; i < nums; i++) {
422 			if (ntohs(str_p[i]) >= stream->incnt) {
423 				result = SCTP_STRRESET_ERR_WRONG_SSN;
424 				goto out;
425 			}
426 		}
427 
428 		for (i = 0; i < nums; i++)
429 			stream->in[ntohs(str_p[i])].ssn = 0;
430 	} else {
431 		for (i = 0; i < stream->incnt; i++)
432 			stream->in[i].ssn = 0;
433 	}
434 
435 	result = SCTP_STRRESET_PERFORMED;
436 
437 	*evp = sctp_ulpevent_make_stream_reset_event(asoc,
438 		flags | SCTP_STREAM_RESET_OUTGOING_SSN, nums, str_p,
439 		GFP_ATOMIC);
440 
441 out:
442 	return sctp_make_strreset_resp(asoc, result, request_seq);
443 }
444 
445 struct sctp_chunk *sctp_process_strreset_inreq(
446 				struct sctp_association *asoc,
447 				union sctp_params param,
448 				struct sctp_ulpevent **evp)
449 {
450 	struct sctp_strreset_inreq *inreq = param.v;
451 	struct sctp_stream *stream = asoc->stream;
452 	__u32 result = SCTP_STRRESET_DENIED;
453 	struct sctp_chunk *chunk = NULL;
454 	__u16 i, nums, *str_p;
455 	__u32 request_seq;
456 
457 	request_seq = ntohl(inreq->request_seq);
458 	if (request_seq > asoc->strreset_inseq) {
459 		result = SCTP_STRRESET_ERR_BAD_SEQNO;
460 		goto out;
461 	} else if (request_seq == asoc->strreset_inseq) {
462 		asoc->strreset_inseq++;
463 	}
464 
465 	if (!(asoc->strreset_enable & SCTP_ENABLE_RESET_STREAM_REQ))
466 		goto out;
467 
468 	if (asoc->strreset_outstanding) {
469 		result = SCTP_STRRESET_ERR_IN_PROGRESS;
470 		goto out;
471 	}
472 
473 	nums = (ntohs(param.p->length) - sizeof(*inreq)) / 2;
474 	str_p = inreq->list_of_streams;
475 	for (i = 0; i < nums; i++) {
476 		if (ntohs(str_p[i]) >= stream->outcnt) {
477 			result = SCTP_STRRESET_ERR_WRONG_SSN;
478 			goto out;
479 		}
480 	}
481 
482 	chunk = sctp_make_strreset_req(asoc, nums, str_p, 1, 0);
483 	if (!chunk)
484 		goto out;
485 
486 	if (nums)
487 		for (i = 0; i < nums; i++)
488 			stream->out[ntohs(str_p[i])].state =
489 					       SCTP_STREAM_CLOSED;
490 	else
491 		for (i = 0; i < stream->outcnt; i++)
492 			stream->out[i].state = SCTP_STREAM_CLOSED;
493 
494 	asoc->strreset_chunk = chunk;
495 	asoc->strreset_outstanding = 1;
496 	sctp_chunk_hold(asoc->strreset_chunk);
497 
498 	*evp = sctp_ulpevent_make_stream_reset_event(asoc,
499 		SCTP_STREAM_RESET_INCOMING_SSN, nums, str_p, GFP_ATOMIC);
500 
501 out:
502 	if (!chunk)
503 		chunk =  sctp_make_strreset_resp(asoc, result, request_seq);
504 
505 	return chunk;
506 }
507