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sysctl: Pass useful parameters to sysctl permissions
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / net / netfilter / nf_conntrack_proto_dccp.c
1 /*
2 * DCCP connection tracking protocol helper
3 *
4 * Copyright (c) 2005, 2006, 2008 Patrick McHardy <kaber@trash.net>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 *
10 */
11 #include <linux/kernel.h>
12 #include <linux/module.h>
13 #include <linux/init.h>
14 #include <linux/sysctl.h>
15 #include <linux/spinlock.h>
16 #include <linux/skbuff.h>
17 #include <linux/dccp.h>
18 #include <linux/slab.h>
19
20 #include <net/net_namespace.h>
21 #include <net/netns/generic.h>
22
23 #include <linux/netfilter/nfnetlink_conntrack.h>
24 #include <net/netfilter/nf_conntrack.h>
25 #include <net/netfilter/nf_conntrack_l4proto.h>
26 #include <net/netfilter/nf_conntrack_ecache.h>
27 #include <net/netfilter/nf_log.h>
28
29 /* Timeouts are based on values from RFC4340:
30 *
31 * - REQUEST:
32 *
33 * 8.1.2. Client Request
34 *
35 * A client MAY give up on its DCCP-Requests after some time
36 * (3 minutes, for example).
37 *
38 * - RESPOND:
39 *
40 * 8.1.3. Server Response
41 *
42 * It MAY also leave the RESPOND state for CLOSED after a timeout of
43 * not less than 4MSL (8 minutes);
44 *
45 * - PARTOPEN:
46 *
47 * 8.1.5. Handshake Completion
48 *
49 * If the client remains in PARTOPEN for more than 4MSL (8 minutes),
50 * it SHOULD reset the connection with Reset Code 2, "Aborted".
51 *
52 * - OPEN:
53 *
54 * The DCCP timestamp overflows after 11.9 hours. If the connection
55 * stays idle this long the sequence number won't be recognized
56 * as valid anymore.
57 *
58 * - CLOSEREQ/CLOSING:
59 *
60 * 8.3. Termination
61 *
62 * The retransmission timer should initially be set to go off in two
63 * round-trip times and should back off to not less than once every
64 * 64 seconds ...
65 *
66 * - TIMEWAIT:
67 *
68 * 4.3. States
69 *
70 * A server or client socket remains in this state for 2MSL (4 minutes)
71 * after the connection has been town down, ...
72 */
73
74 #define DCCP_MSL (2 * 60 * HZ)
75
76 static const char * const dccp_state_names[] = {
77 [CT_DCCP_NONE] = "NONE",
78 [CT_DCCP_REQUEST] = "REQUEST",
79 [CT_DCCP_RESPOND] = "RESPOND",
80 [CT_DCCP_PARTOPEN] = "PARTOPEN",
81 [CT_DCCP_OPEN] = "OPEN",
82 [CT_DCCP_CLOSEREQ] = "CLOSEREQ",
83 [CT_DCCP_CLOSING] = "CLOSING",
84 [CT_DCCP_TIMEWAIT] = "TIMEWAIT",
85 [CT_DCCP_IGNORE] = "IGNORE",
86 [CT_DCCP_INVALID] = "INVALID",
87 };
88
89 #define sNO CT_DCCP_NONE
90 #define sRQ CT_DCCP_REQUEST
91 #define sRS CT_DCCP_RESPOND
92 #define sPO CT_DCCP_PARTOPEN
93 #define sOP CT_DCCP_OPEN
94 #define sCR CT_DCCP_CLOSEREQ
95 #define sCG CT_DCCP_CLOSING
96 #define sTW CT_DCCP_TIMEWAIT
97 #define sIG CT_DCCP_IGNORE
98 #define sIV CT_DCCP_INVALID
99
100 /*
101 * DCCP state transition table
102 *
103 * The assumption is the same as for TCP tracking:
104 *
105 * We are the man in the middle. All the packets go through us but might
106 * get lost in transit to the destination. It is assumed that the destination
107 * can't receive segments we haven't seen.
108 *
109 * The following states exist:
110 *
111 * NONE: Initial state, expecting Request
112 * REQUEST: Request seen, waiting for Response from server
113 * RESPOND: Response from server seen, waiting for Ack from client
114 * PARTOPEN: Ack after Response seen, waiting for packet other than Response,
115 * Reset or Sync from server
116 * OPEN: Packet other than Response, Reset or Sync seen
117 * CLOSEREQ: CloseReq from server seen, expecting Close from client
118 * CLOSING: Close seen, expecting Reset
119 * TIMEWAIT: Reset seen
120 * IGNORE: Not determinable whether packet is valid
121 *
122 * Some states exist only on one side of the connection: REQUEST, RESPOND,
123 * PARTOPEN, CLOSEREQ. For the other side these states are equivalent to
124 * the one it was in before.
125 *
126 * Packets are marked as ignored (sIG) if we don't know if they're valid
127 * (for example a reincarnation of a connection we didn't notice is dead
128 * already) and the server may send back a connection closing Reset or a
129 * Response. They're also used for Sync/SyncAck packets, which we don't
130 * care about.
131 */
132 static const u_int8_t
133 dccp_state_table[CT_DCCP_ROLE_MAX + 1][DCCP_PKT_SYNCACK + 1][CT_DCCP_MAX + 1] = {
134 [CT_DCCP_ROLE_CLIENT] = {
135 [DCCP_PKT_REQUEST] = {
136 /*
137 * sNO -> sRQ Regular Request
138 * sRQ -> sRQ Retransmitted Request or reincarnation
139 * sRS -> sRS Retransmitted Request (apparently Response
140 * got lost after we saw it) or reincarnation
141 * sPO -> sIG Ignore, conntrack might be out of sync
142 * sOP -> sIG Ignore, conntrack might be out of sync
143 * sCR -> sIG Ignore, conntrack might be out of sync
144 * sCG -> sIG Ignore, conntrack might be out of sync
145 * sTW -> sRQ Reincarnation
146 *
147 * sNO, sRQ, sRS, sPO. sOP, sCR, sCG, sTW, */
148 sRQ, sRQ, sRS, sIG, sIG, sIG, sIG, sRQ,
149 },
150 [DCCP_PKT_RESPONSE] = {
151 /*
152 * sNO -> sIV Invalid
153 * sRQ -> sIG Ignore, might be response to ignored Request
154 * sRS -> sIG Ignore, might be response to ignored Request
155 * sPO -> sIG Ignore, might be response to ignored Request
156 * sOP -> sIG Ignore, might be response to ignored Request
157 * sCR -> sIG Ignore, might be response to ignored Request
158 * sCG -> sIG Ignore, might be response to ignored Request
159 * sTW -> sIV Invalid, reincarnation in reverse direction
160 * goes through sRQ
161 *
162 * sNO, sRQ, sRS, sPO, sOP, sCR, sCG, sTW */
163 sIV, sIG, sIG, sIG, sIG, sIG, sIG, sIV,
164 },
165 [DCCP_PKT_ACK] = {
166 /*
167 * sNO -> sIV No connection
168 * sRQ -> sIV No connection
169 * sRS -> sPO Ack for Response, move to PARTOPEN (8.1.5.)
170 * sPO -> sPO Retransmitted Ack for Response, remain in PARTOPEN
171 * sOP -> sOP Regular ACK, remain in OPEN
172 * sCR -> sCR Ack in CLOSEREQ MAY be processed (8.3.)
173 * sCG -> sCG Ack in CLOSING MAY be processed (8.3.)
174 * sTW -> sIV
175 *
176 * sNO, sRQ, sRS, sPO, sOP, sCR, sCG, sTW */
177 sIV, sIV, sPO, sPO, sOP, sCR, sCG, sIV
178 },
179 [DCCP_PKT_DATA] = {
180 /*
181 * sNO -> sIV No connection
182 * sRQ -> sIV No connection
183 * sRS -> sIV No connection
184 * sPO -> sIV MUST use DataAck in PARTOPEN state (8.1.5.)
185 * sOP -> sOP Regular Data packet
186 * sCR -> sCR Data in CLOSEREQ MAY be processed (8.3.)
187 * sCG -> sCG Data in CLOSING MAY be processed (8.3.)
188 * sTW -> sIV
189 *
190 * sNO, sRQ, sRS, sPO, sOP, sCR, sCG, sTW */
191 sIV, sIV, sIV, sIV, sOP, sCR, sCG, sIV,
192 },
193 [DCCP_PKT_DATAACK] = {
194 /*
195 * sNO -> sIV No connection
196 * sRQ -> sIV No connection
197 * sRS -> sPO Ack for Response, move to PARTOPEN (8.1.5.)
198 * sPO -> sPO Remain in PARTOPEN state
199 * sOP -> sOP Regular DataAck packet in OPEN state
200 * sCR -> sCR DataAck in CLOSEREQ MAY be processed (8.3.)
201 * sCG -> sCG DataAck in CLOSING MAY be processed (8.3.)
202 * sTW -> sIV
203 *
204 * sNO, sRQ, sRS, sPO, sOP, sCR, sCG, sTW */
205 sIV, sIV, sPO, sPO, sOP, sCR, sCG, sIV
206 },
207 [DCCP_PKT_CLOSEREQ] = {
208 /*
209 * CLOSEREQ may only be sent by the server.
210 *
211 * sNO, sRQ, sRS, sPO, sOP, sCR, sCG, sTW */
212 sIV, sIV, sIV, sIV, sIV, sIV, sIV, sIV
213 },
214 [DCCP_PKT_CLOSE] = {
215 /*
216 * sNO -> sIV No connection
217 * sRQ -> sIV No connection
218 * sRS -> sIV No connection
219 * sPO -> sCG Client-initiated close
220 * sOP -> sCG Client-initiated close
221 * sCR -> sCG Close in response to CloseReq (8.3.)
222 * sCG -> sCG Retransmit
223 * sTW -> sIV Late retransmit, already in TIME_WAIT
224 *
225 * sNO, sRQ, sRS, sPO, sOP, sCR, sCG, sTW */
226 sIV, sIV, sIV, sCG, sCG, sCG, sIV, sIV
227 },
228 [DCCP_PKT_RESET] = {
229 /*
230 * sNO -> sIV No connection
231 * sRQ -> sTW Sync received or timeout, SHOULD send Reset (8.1.1.)
232 * sRS -> sTW Response received without Request
233 * sPO -> sTW Timeout, SHOULD send Reset (8.1.5.)
234 * sOP -> sTW Connection reset
235 * sCR -> sTW Connection reset
236 * sCG -> sTW Connection reset
237 * sTW -> sIG Ignore (don't refresh timer)
238 *
239 * sNO, sRQ, sRS, sPO, sOP, sCR, sCG, sTW */
240 sIV, sTW, sTW, sTW, sTW, sTW, sTW, sIG
241 },
242 [DCCP_PKT_SYNC] = {
243 /*
244 * We currently ignore Sync packets
245 *
246 * sNO, sRQ, sRS, sPO, sOP, sCR, sCG, sTW */
247 sIG, sIG, sIG, sIG, sIG, sIG, sIG, sIG,
248 },
249 [DCCP_PKT_SYNCACK] = {
250 /*
251 * We currently ignore SyncAck packets
252 *
253 * sNO, sRQ, sRS, sPO, sOP, sCR, sCG, sTW */
254 sIG, sIG, sIG, sIG, sIG, sIG, sIG, sIG,
255 },
256 },
257 [CT_DCCP_ROLE_SERVER] = {
258 [DCCP_PKT_REQUEST] = {
259 /*
260 * sNO -> sIV Invalid
261 * sRQ -> sIG Ignore, conntrack might be out of sync
262 * sRS -> sIG Ignore, conntrack might be out of sync
263 * sPO -> sIG Ignore, conntrack might be out of sync
264 * sOP -> sIG Ignore, conntrack might be out of sync
265 * sCR -> sIG Ignore, conntrack might be out of sync
266 * sCG -> sIG Ignore, conntrack might be out of sync
267 * sTW -> sRQ Reincarnation, must reverse roles
268 *
269 * sNO, sRQ, sRS, sPO, sOP, sCR, sCG, sTW */
270 sIV, sIG, sIG, sIG, sIG, sIG, sIG, sRQ
271 },
272 [DCCP_PKT_RESPONSE] = {
273 /*
274 * sNO -> sIV Response without Request
275 * sRQ -> sRS Response to clients Request
276 * sRS -> sRS Retransmitted Response (8.1.3. SHOULD NOT)
277 * sPO -> sIG Response to an ignored Request or late retransmit
278 * sOP -> sIG Ignore, might be response to ignored Request
279 * sCR -> sIG Ignore, might be response to ignored Request
280 * sCG -> sIG Ignore, might be response to ignored Request
281 * sTW -> sIV Invalid, Request from client in sTW moves to sRQ
282 *
283 * sNO, sRQ, sRS, sPO, sOP, sCR, sCG, sTW */
284 sIV, sRS, sRS, sIG, sIG, sIG, sIG, sIV
285 },
286 [DCCP_PKT_ACK] = {
287 /*
288 * sNO -> sIV No connection
289 * sRQ -> sIV No connection
290 * sRS -> sIV No connection
291 * sPO -> sOP Enter OPEN state (8.1.5.)
292 * sOP -> sOP Regular Ack in OPEN state
293 * sCR -> sIV Waiting for Close from client
294 * sCG -> sCG Ack in CLOSING MAY be processed (8.3.)
295 * sTW -> sIV
296 *
297 * sNO, sRQ, sRS, sPO, sOP, sCR, sCG, sTW */
298 sIV, sIV, sIV, sOP, sOP, sIV, sCG, sIV
299 },
300 [DCCP_PKT_DATA] = {
301 /*
302 * sNO -> sIV No connection
303 * sRQ -> sIV No connection
304 * sRS -> sIV No connection
305 * sPO -> sOP Enter OPEN state (8.1.5.)
306 * sOP -> sOP Regular Data packet in OPEN state
307 * sCR -> sIV Waiting for Close from client
308 * sCG -> sCG Data in CLOSING MAY be processed (8.3.)
309 * sTW -> sIV
310 *
311 * sNO, sRQ, sRS, sPO, sOP, sCR, sCG, sTW */
312 sIV, sIV, sIV, sOP, sOP, sIV, sCG, sIV
313 },
314 [DCCP_PKT_DATAACK] = {
315 /*
316 * sNO -> sIV No connection
317 * sRQ -> sIV No connection
318 * sRS -> sIV No connection
319 * sPO -> sOP Enter OPEN state (8.1.5.)
320 * sOP -> sOP Regular DataAck in OPEN state
321 * sCR -> sIV Waiting for Close from client
322 * sCG -> sCG Data in CLOSING MAY be processed (8.3.)
323 * sTW -> sIV
324 *
325 * sNO, sRQ, sRS, sPO, sOP, sCR, sCG, sTW */
326 sIV, sIV, sIV, sOP, sOP, sIV, sCG, sIV
327 },
328 [DCCP_PKT_CLOSEREQ] = {
329 /*
330 * sNO -> sIV No connection
331 * sRQ -> sIV No connection
332 * sRS -> sIV No connection
333 * sPO -> sOP -> sCR Move directly to CLOSEREQ (8.1.5.)
334 * sOP -> sCR CloseReq in OPEN state
335 * sCR -> sCR Retransmit
336 * sCG -> sCR Simultaneous close, client sends another Close
337 * sTW -> sIV Already closed
338 *
339 * sNO, sRQ, sRS, sPO, sOP, sCR, sCG, sTW */
340 sIV, sIV, sIV, sCR, sCR, sCR, sCR, sIV
341 },
342 [DCCP_PKT_CLOSE] = {
343 /*
344 * sNO -> sIV No connection
345 * sRQ -> sIV No connection
346 * sRS -> sIV No connection
347 * sPO -> sOP -> sCG Move direcly to CLOSING
348 * sOP -> sCG Move to CLOSING
349 * sCR -> sIV Close after CloseReq is invalid
350 * sCG -> sCG Retransmit
351 * sTW -> sIV Already closed
352 *
353 * sNO, sRQ, sRS, sPO, sOP, sCR, sCG, sTW */
354 sIV, sIV, sIV, sCG, sCG, sIV, sCG, sIV
355 },
356 [DCCP_PKT_RESET] = {
357 /*
358 * sNO -> sIV No connection
359 * sRQ -> sTW Reset in response to Request
360 * sRS -> sTW Timeout, SHOULD send Reset (8.1.3.)
361 * sPO -> sTW Timeout, SHOULD send Reset (8.1.3.)
362 * sOP -> sTW
363 * sCR -> sTW
364 * sCG -> sTW
365 * sTW -> sIG Ignore (don't refresh timer)
366 *
367 * sNO, sRQ, sRS, sPO, sOP, sCR, sCG, sTW, sTW */
368 sIV, sTW, sTW, sTW, sTW, sTW, sTW, sTW, sIG
369 },
370 [DCCP_PKT_SYNC] = {
371 /*
372 * We currently ignore Sync packets
373 *
374 * sNO, sRQ, sRS, sPO, sOP, sCR, sCG, sTW */
375 sIG, sIG, sIG, sIG, sIG, sIG, sIG, sIG,
376 },
377 [DCCP_PKT_SYNCACK] = {
378 /*
379 * We currently ignore SyncAck packets
380 *
381 * sNO, sRQ, sRS, sPO, sOP, sCR, sCG, sTW */
382 sIG, sIG, sIG, sIG, sIG, sIG, sIG, sIG,
383 },
384 },
385 };
386
387 /* this module per-net specifics */
388 static int dccp_net_id __read_mostly;
389 struct dccp_net {
390 struct nf_proto_net pn;
391 int dccp_loose;
392 unsigned int dccp_timeout[CT_DCCP_MAX + 1];
393 };
394
395 static inline struct dccp_net *dccp_pernet(struct net *net)
396 {
397 return net_generic(net, dccp_net_id);
398 }
399
400 static bool dccp_pkt_to_tuple(const struct sk_buff *skb, unsigned int dataoff,
401 struct nf_conntrack_tuple *tuple)
402 {
403 struct dccp_hdr _hdr, *dh;
404
405 dh = skb_header_pointer(skb, dataoff, sizeof(_hdr), &_hdr);
406 if (dh == NULL)
407 return false;
408
409 tuple->src.u.dccp.port = dh->dccph_sport;
410 tuple->dst.u.dccp.port = dh->dccph_dport;
411 return true;
412 }
413
414 static bool dccp_invert_tuple(struct nf_conntrack_tuple *inv,
415 const struct nf_conntrack_tuple *tuple)
416 {
417 inv->src.u.dccp.port = tuple->dst.u.dccp.port;
418 inv->dst.u.dccp.port = tuple->src.u.dccp.port;
419 return true;
420 }
421
422 static bool dccp_new(struct nf_conn *ct, const struct sk_buff *skb,
423 unsigned int dataoff, unsigned int *timeouts)
424 {
425 struct net *net = nf_ct_net(ct);
426 struct dccp_net *dn;
427 struct dccp_hdr _dh, *dh;
428 const char *msg;
429 u_int8_t state;
430
431 dh = skb_header_pointer(skb, dataoff, sizeof(_dh), &dh);
432 BUG_ON(dh == NULL);
433
434 state = dccp_state_table[CT_DCCP_ROLE_CLIENT][dh->dccph_type][CT_DCCP_NONE];
435 switch (state) {
436 default:
437 dn = dccp_pernet(net);
438 if (dn->dccp_loose == 0) {
439 msg = "nf_ct_dccp: not picking up existing connection ";
440 goto out_invalid;
441 }
442 case CT_DCCP_REQUEST:
443 break;
444 case CT_DCCP_INVALID:
445 msg = "nf_ct_dccp: invalid state transition ";
446 goto out_invalid;
447 }
448
449 ct->proto.dccp.role[IP_CT_DIR_ORIGINAL] = CT_DCCP_ROLE_CLIENT;
450 ct->proto.dccp.role[IP_CT_DIR_REPLY] = CT_DCCP_ROLE_SERVER;
451 ct->proto.dccp.state = CT_DCCP_NONE;
452 ct->proto.dccp.last_pkt = DCCP_PKT_REQUEST;
453 ct->proto.dccp.last_dir = IP_CT_DIR_ORIGINAL;
454 ct->proto.dccp.handshake_seq = 0;
455 return true;
456
457 out_invalid:
458 if (LOG_INVALID(net, IPPROTO_DCCP))
459 nf_log_packet(nf_ct_l3num(ct), 0, skb, NULL, NULL, NULL, msg);
460 return false;
461 }
462
463 static u64 dccp_ack_seq(const struct dccp_hdr *dh)
464 {
465 const struct dccp_hdr_ack_bits *dhack;
466
467 dhack = (void *)dh + __dccp_basic_hdr_len(dh);
468 return ((u64)ntohs(dhack->dccph_ack_nr_high) << 32) +
469 ntohl(dhack->dccph_ack_nr_low);
470 }
471
472 static unsigned int *dccp_get_timeouts(struct net *net)
473 {
474 return dccp_pernet(net)->dccp_timeout;
475 }
476
477 static int dccp_packet(struct nf_conn *ct, const struct sk_buff *skb,
478 unsigned int dataoff, enum ip_conntrack_info ctinfo,
479 u_int8_t pf, unsigned int hooknum,
480 unsigned int *timeouts)
481 {
482 struct net *net = nf_ct_net(ct);
483 enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo);
484 struct dccp_hdr _dh, *dh;
485 u_int8_t type, old_state, new_state;
486 enum ct_dccp_roles role;
487
488 dh = skb_header_pointer(skb, dataoff, sizeof(_dh), &dh);
489 BUG_ON(dh == NULL);
490 type = dh->dccph_type;
491
492 if (type == DCCP_PKT_RESET &&
493 !test_bit(IPS_SEEN_REPLY_BIT, &ct->status)) {
494 /* Tear down connection immediately if only reply is a RESET */
495 nf_ct_kill_acct(ct, ctinfo, skb);
496 return NF_ACCEPT;
497 }
498
499 spin_lock_bh(&ct->lock);
500
501 role = ct->proto.dccp.role[dir];
502 old_state = ct->proto.dccp.state;
503 new_state = dccp_state_table[role][type][old_state];
504
505 switch (new_state) {
506 case CT_DCCP_REQUEST:
507 if (old_state == CT_DCCP_TIMEWAIT &&
508 role == CT_DCCP_ROLE_SERVER) {
509 /* Reincarnation in the reverse direction: reopen and
510 * reverse client/server roles. */
511 ct->proto.dccp.role[dir] = CT_DCCP_ROLE_CLIENT;
512 ct->proto.dccp.role[!dir] = CT_DCCP_ROLE_SERVER;
513 }
514 break;
515 case CT_DCCP_RESPOND:
516 if (old_state == CT_DCCP_REQUEST)
517 ct->proto.dccp.handshake_seq = dccp_hdr_seq(dh);
518 break;
519 case CT_DCCP_PARTOPEN:
520 if (old_state == CT_DCCP_RESPOND &&
521 type == DCCP_PKT_ACK &&
522 dccp_ack_seq(dh) == ct->proto.dccp.handshake_seq)
523 set_bit(IPS_ASSURED_BIT, &ct->status);
524 break;
525 case CT_DCCP_IGNORE:
526 /*
527 * Connection tracking might be out of sync, so we ignore
528 * packets that might establish a new connection and resync
529 * if the server responds with a valid Response.
530 */
531 if (ct->proto.dccp.last_dir == !dir &&
532 ct->proto.dccp.last_pkt == DCCP_PKT_REQUEST &&
533 type == DCCP_PKT_RESPONSE) {
534 ct->proto.dccp.role[!dir] = CT_DCCP_ROLE_CLIENT;
535 ct->proto.dccp.role[dir] = CT_DCCP_ROLE_SERVER;
536 ct->proto.dccp.handshake_seq = dccp_hdr_seq(dh);
537 new_state = CT_DCCP_RESPOND;
538 break;
539 }
540 ct->proto.dccp.last_dir = dir;
541 ct->proto.dccp.last_pkt = type;
542
543 spin_unlock_bh(&ct->lock);
544 if (LOG_INVALID(net, IPPROTO_DCCP))
545 nf_log_packet(pf, 0, skb, NULL, NULL, NULL,
546 "nf_ct_dccp: invalid packet ignored ");
547 return NF_ACCEPT;
548 case CT_DCCP_INVALID:
549 spin_unlock_bh(&ct->lock);
550 if (LOG_INVALID(net, IPPROTO_DCCP))
551 nf_log_packet(pf, 0, skb, NULL, NULL, NULL,
552 "nf_ct_dccp: invalid state transition ");
553 return -NF_ACCEPT;
554 }
555
556 ct->proto.dccp.last_dir = dir;
557 ct->proto.dccp.last_pkt = type;
558 ct->proto.dccp.state = new_state;
559 spin_unlock_bh(&ct->lock);
560
561 if (new_state != old_state)
562 nf_conntrack_event_cache(IPCT_PROTOINFO, ct);
563
564 nf_ct_refresh_acct(ct, ctinfo, skb, timeouts[new_state]);
565
566 return NF_ACCEPT;
567 }
568
569 static int dccp_error(struct net *net, struct nf_conn *tmpl,
570 struct sk_buff *skb, unsigned int dataoff,
571 enum ip_conntrack_info *ctinfo,
572 u_int8_t pf, unsigned int hooknum)
573 {
574 struct dccp_hdr _dh, *dh;
575 unsigned int dccp_len = skb->len - dataoff;
576 unsigned int cscov;
577 const char *msg;
578
579 dh = skb_header_pointer(skb, dataoff, sizeof(_dh), &dh);
580 if (dh == NULL) {
581 msg = "nf_ct_dccp: short packet ";
582 goto out_invalid;
583 }
584
585 if (dh->dccph_doff * 4 < sizeof(struct dccp_hdr) ||
586 dh->dccph_doff * 4 > dccp_len) {
587 msg = "nf_ct_dccp: truncated/malformed packet ";
588 goto out_invalid;
589 }
590
591 cscov = dccp_len;
592 if (dh->dccph_cscov) {
593 cscov = (dh->dccph_cscov - 1) * 4;
594 if (cscov > dccp_len) {
595 msg = "nf_ct_dccp: bad checksum coverage ";
596 goto out_invalid;
597 }
598 }
599
600 if (net->ct.sysctl_checksum && hooknum == NF_INET_PRE_ROUTING &&
601 nf_checksum_partial(skb, hooknum, dataoff, cscov, IPPROTO_DCCP,
602 pf)) {
603 msg = "nf_ct_dccp: bad checksum ";
604 goto out_invalid;
605 }
606
607 if (dh->dccph_type >= DCCP_PKT_INVALID) {
608 msg = "nf_ct_dccp: reserved packet type ";
609 goto out_invalid;
610 }
611
612 return NF_ACCEPT;
613
614 out_invalid:
615 if (LOG_INVALID(net, IPPROTO_DCCP))
616 nf_log_packet(pf, 0, skb, NULL, NULL, NULL, msg);
617 return -NF_ACCEPT;
618 }
619
620 static int dccp_print_tuple(struct seq_file *s,
621 const struct nf_conntrack_tuple *tuple)
622 {
623 return seq_printf(s, "sport=%hu dport=%hu ",
624 ntohs(tuple->src.u.dccp.port),
625 ntohs(tuple->dst.u.dccp.port));
626 }
627
628 static int dccp_print_conntrack(struct seq_file *s, struct nf_conn *ct)
629 {
630 return seq_printf(s, "%s ", dccp_state_names[ct->proto.dccp.state]);
631 }
632
633 #if IS_ENABLED(CONFIG_NF_CT_NETLINK)
634 static int dccp_to_nlattr(struct sk_buff *skb, struct nlattr *nla,
635 struct nf_conn *ct)
636 {
637 struct nlattr *nest_parms;
638
639 spin_lock_bh(&ct->lock);
640 nest_parms = nla_nest_start(skb, CTA_PROTOINFO_DCCP | NLA_F_NESTED);
641 if (!nest_parms)
642 goto nla_put_failure;
643 if (nla_put_u8(skb, CTA_PROTOINFO_DCCP_STATE, ct->proto.dccp.state) ||
644 nla_put_u8(skb, CTA_PROTOINFO_DCCP_ROLE,
645 ct->proto.dccp.role[IP_CT_DIR_ORIGINAL]) ||
646 nla_put_be64(skb, CTA_PROTOINFO_DCCP_HANDSHAKE_SEQ,
647 cpu_to_be64(ct->proto.dccp.handshake_seq)))
648 goto nla_put_failure;
649 nla_nest_end(skb, nest_parms);
650 spin_unlock_bh(&ct->lock);
651 return 0;
652
653 nla_put_failure:
654 spin_unlock_bh(&ct->lock);
655 return -1;
656 }
657
658 static const struct nla_policy dccp_nla_policy[CTA_PROTOINFO_DCCP_MAX + 1] = {
659 [CTA_PROTOINFO_DCCP_STATE] = { .type = NLA_U8 },
660 [CTA_PROTOINFO_DCCP_ROLE] = { .type = NLA_U8 },
661 [CTA_PROTOINFO_DCCP_HANDSHAKE_SEQ] = { .type = NLA_U64 },
662 };
663
664 static int nlattr_to_dccp(struct nlattr *cda[], struct nf_conn *ct)
665 {
666 struct nlattr *attr = cda[CTA_PROTOINFO_DCCP];
667 struct nlattr *tb[CTA_PROTOINFO_DCCP_MAX + 1];
668 int err;
669
670 if (!attr)
671 return 0;
672
673 err = nla_parse_nested(tb, CTA_PROTOINFO_DCCP_MAX, attr,
674 dccp_nla_policy);
675 if (err < 0)
676 return err;
677
678 if (!tb[CTA_PROTOINFO_DCCP_STATE] ||
679 !tb[CTA_PROTOINFO_DCCP_ROLE] ||
680 nla_get_u8(tb[CTA_PROTOINFO_DCCP_ROLE]) > CT_DCCP_ROLE_MAX ||
681 nla_get_u8(tb[CTA_PROTOINFO_DCCP_STATE]) >= CT_DCCP_IGNORE) {
682 return -EINVAL;
683 }
684
685 spin_lock_bh(&ct->lock);
686 ct->proto.dccp.state = nla_get_u8(tb[CTA_PROTOINFO_DCCP_STATE]);
687 if (nla_get_u8(tb[CTA_PROTOINFO_DCCP_ROLE]) == CT_DCCP_ROLE_CLIENT) {
688 ct->proto.dccp.role[IP_CT_DIR_ORIGINAL] = CT_DCCP_ROLE_CLIENT;
689 ct->proto.dccp.role[IP_CT_DIR_REPLY] = CT_DCCP_ROLE_SERVER;
690 } else {
691 ct->proto.dccp.role[IP_CT_DIR_ORIGINAL] = CT_DCCP_ROLE_SERVER;
692 ct->proto.dccp.role[IP_CT_DIR_REPLY] = CT_DCCP_ROLE_CLIENT;
693 }
694 if (tb[CTA_PROTOINFO_DCCP_HANDSHAKE_SEQ]) {
695 ct->proto.dccp.handshake_seq =
696 be64_to_cpu(nla_get_be64(tb[CTA_PROTOINFO_DCCP_HANDSHAKE_SEQ]));
697 }
698 spin_unlock_bh(&ct->lock);
699 return 0;
700 }
701
702 static int dccp_nlattr_size(void)
703 {
704 return nla_total_size(0) /* CTA_PROTOINFO_DCCP */
705 + nla_policy_len(dccp_nla_policy, CTA_PROTOINFO_DCCP_MAX + 1);
706 }
707
708 #endif
709
710 #if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT)
711
712 #include <linux/netfilter/nfnetlink.h>
713 #include <linux/netfilter/nfnetlink_cttimeout.h>
714
715 static int dccp_timeout_nlattr_to_obj(struct nlattr *tb[],
716 struct net *net, void *data)
717 {
718 struct dccp_net *dn = dccp_pernet(net);
719 unsigned int *timeouts = data;
720 int i;
721
722 /* set default DCCP timeouts. */
723 for (i=0; i<CT_DCCP_MAX; i++)
724 timeouts[i] = dn->dccp_timeout[i];
725
726 /* there's a 1:1 mapping between attributes and protocol states. */
727 for (i=CTA_TIMEOUT_DCCP_UNSPEC+1; i<CTA_TIMEOUT_DCCP_MAX+1; i++) {
728 if (tb[i]) {
729 timeouts[i] = ntohl(nla_get_be32(tb[i])) * HZ;
730 }
731 }
732 return 0;
733 }
734
735 static int
736 dccp_timeout_obj_to_nlattr(struct sk_buff *skb, const void *data)
737 {
738 const unsigned int *timeouts = data;
739 int i;
740
741 for (i=CTA_TIMEOUT_DCCP_UNSPEC+1; i<CTA_TIMEOUT_DCCP_MAX+1; i++) {
742 if (nla_put_be32(skb, i, htonl(timeouts[i] / HZ)))
743 goto nla_put_failure;
744 }
745 return 0;
746
747 nla_put_failure:
748 return -ENOSPC;
749 }
750
751 static const struct nla_policy
752 dccp_timeout_nla_policy[CTA_TIMEOUT_DCCP_MAX+1] = {
753 [CTA_TIMEOUT_DCCP_REQUEST] = { .type = NLA_U32 },
754 [CTA_TIMEOUT_DCCP_RESPOND] = { .type = NLA_U32 },
755 [CTA_TIMEOUT_DCCP_PARTOPEN] = { .type = NLA_U32 },
756 [CTA_TIMEOUT_DCCP_OPEN] = { .type = NLA_U32 },
757 [CTA_TIMEOUT_DCCP_CLOSEREQ] = { .type = NLA_U32 },
758 [CTA_TIMEOUT_DCCP_CLOSING] = { .type = NLA_U32 },
759 [CTA_TIMEOUT_DCCP_TIMEWAIT] = { .type = NLA_U32 },
760 };
761 #endif /* CONFIG_NF_CT_NETLINK_TIMEOUT */
762
763 #ifdef CONFIG_SYSCTL
764 /* template, data assigned later */
765 static struct ctl_table dccp_sysctl_table[] = {
766 {
767 .procname = "nf_conntrack_dccp_timeout_request",
768 .maxlen = sizeof(unsigned int),
769 .mode = 0644,
770 .proc_handler = proc_dointvec_jiffies,
771 },
772 {
773 .procname = "nf_conntrack_dccp_timeout_respond",
774 .maxlen = sizeof(unsigned int),
775 .mode = 0644,
776 .proc_handler = proc_dointvec_jiffies,
777 },
778 {
779 .procname = "nf_conntrack_dccp_timeout_partopen",
780 .maxlen = sizeof(unsigned int),
781 .mode = 0644,
782 .proc_handler = proc_dointvec_jiffies,
783 },
784 {
785 .procname = "nf_conntrack_dccp_timeout_open",
786 .maxlen = sizeof(unsigned int),
787 .mode = 0644,
788 .proc_handler = proc_dointvec_jiffies,
789 },
790 {
791 .procname = "nf_conntrack_dccp_timeout_closereq",
792 .maxlen = sizeof(unsigned int),
793 .mode = 0644,
794 .proc_handler = proc_dointvec_jiffies,
795 },
796 {
797 .procname = "nf_conntrack_dccp_timeout_closing",
798 .maxlen = sizeof(unsigned int),
799 .mode = 0644,
800 .proc_handler = proc_dointvec_jiffies,
801 },
802 {
803 .procname = "nf_conntrack_dccp_timeout_timewait",
804 .maxlen = sizeof(unsigned int),
805 .mode = 0644,
806 .proc_handler = proc_dointvec_jiffies,
807 },
808 {
809 .procname = "nf_conntrack_dccp_loose",
810 .maxlen = sizeof(int),
811 .mode = 0644,
812 .proc_handler = proc_dointvec,
813 },
814 { }
815 };
816 #endif /* CONFIG_SYSCTL */
817
818 static int dccp_kmemdup_sysctl_table(struct nf_proto_net *pn,
819 struct dccp_net *dn)
820 {
821 #ifdef CONFIG_SYSCTL
822 if (pn->ctl_table)
823 return 0;
824
825 pn->ctl_table = kmemdup(dccp_sysctl_table,
826 sizeof(dccp_sysctl_table),
827 GFP_KERNEL);
828 if (!pn->ctl_table)
829 return -ENOMEM;
830
831 pn->ctl_table[0].data = &dn->dccp_timeout[CT_DCCP_REQUEST];
832 pn->ctl_table[1].data = &dn->dccp_timeout[CT_DCCP_RESPOND];
833 pn->ctl_table[2].data = &dn->dccp_timeout[CT_DCCP_PARTOPEN];
834 pn->ctl_table[3].data = &dn->dccp_timeout[CT_DCCP_OPEN];
835 pn->ctl_table[4].data = &dn->dccp_timeout[CT_DCCP_CLOSEREQ];
836 pn->ctl_table[5].data = &dn->dccp_timeout[CT_DCCP_CLOSING];
837 pn->ctl_table[6].data = &dn->dccp_timeout[CT_DCCP_TIMEWAIT];
838 pn->ctl_table[7].data = &dn->dccp_loose;
839 #endif
840 return 0;
841 }
842
843 static int dccp_init_net(struct net *net, u_int16_t proto)
844 {
845 struct dccp_net *dn = dccp_pernet(net);
846 struct nf_proto_net *pn = &dn->pn;
847
848 if (!pn->users) {
849 /* default values */
850 dn->dccp_loose = 1;
851 dn->dccp_timeout[CT_DCCP_REQUEST] = 2 * DCCP_MSL;
852 dn->dccp_timeout[CT_DCCP_RESPOND] = 4 * DCCP_MSL;
853 dn->dccp_timeout[CT_DCCP_PARTOPEN] = 4 * DCCP_MSL;
854 dn->dccp_timeout[CT_DCCP_OPEN] = 12 * 3600 * HZ;
855 dn->dccp_timeout[CT_DCCP_CLOSEREQ] = 64 * HZ;
856 dn->dccp_timeout[CT_DCCP_CLOSING] = 64 * HZ;
857 dn->dccp_timeout[CT_DCCP_TIMEWAIT] = 2 * DCCP_MSL;
858 }
859
860 return dccp_kmemdup_sysctl_table(pn, dn);
861 }
862
863 static struct nf_conntrack_l4proto dccp_proto4 __read_mostly = {
864 .l3proto = AF_INET,
865 .l4proto = IPPROTO_DCCP,
866 .name = "dccp",
867 .pkt_to_tuple = dccp_pkt_to_tuple,
868 .invert_tuple = dccp_invert_tuple,
869 .new = dccp_new,
870 .packet = dccp_packet,
871 .get_timeouts = dccp_get_timeouts,
872 .error = dccp_error,
873 .print_tuple = dccp_print_tuple,
874 .print_conntrack = dccp_print_conntrack,
875 #if IS_ENABLED(CONFIG_NF_CT_NETLINK)
876 .to_nlattr = dccp_to_nlattr,
877 .nlattr_size = dccp_nlattr_size,
878 .from_nlattr = nlattr_to_dccp,
879 .tuple_to_nlattr = nf_ct_port_tuple_to_nlattr,
880 .nlattr_tuple_size = nf_ct_port_nlattr_tuple_size,
881 .nlattr_to_tuple = nf_ct_port_nlattr_to_tuple,
882 .nla_policy = nf_ct_port_nla_policy,
883 #endif
884 #if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT)
885 .ctnl_timeout = {
886 .nlattr_to_obj = dccp_timeout_nlattr_to_obj,
887 .obj_to_nlattr = dccp_timeout_obj_to_nlattr,
888 .nlattr_max = CTA_TIMEOUT_DCCP_MAX,
889 .obj_size = sizeof(unsigned int) * CT_DCCP_MAX,
890 .nla_policy = dccp_timeout_nla_policy,
891 },
892 #endif /* CONFIG_NF_CT_NETLINK_TIMEOUT */
893 .net_id = &dccp_net_id,
894 .init_net = dccp_init_net,
895 };
896
897 static struct nf_conntrack_l4proto dccp_proto6 __read_mostly = {
898 .l3proto = AF_INET6,
899 .l4proto = IPPROTO_DCCP,
900 .name = "dccp",
901 .pkt_to_tuple = dccp_pkt_to_tuple,
902 .invert_tuple = dccp_invert_tuple,
903 .new = dccp_new,
904 .packet = dccp_packet,
905 .get_timeouts = dccp_get_timeouts,
906 .error = dccp_error,
907 .print_tuple = dccp_print_tuple,
908 .print_conntrack = dccp_print_conntrack,
909 #if IS_ENABLED(CONFIG_NF_CT_NETLINK)
910 .to_nlattr = dccp_to_nlattr,
911 .nlattr_size = dccp_nlattr_size,
912 .from_nlattr = nlattr_to_dccp,
913 .tuple_to_nlattr = nf_ct_port_tuple_to_nlattr,
914 .nlattr_tuple_size = nf_ct_port_nlattr_tuple_size,
915 .nlattr_to_tuple = nf_ct_port_nlattr_to_tuple,
916 .nla_policy = nf_ct_port_nla_policy,
917 #endif
918 #if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT)
919 .ctnl_timeout = {
920 .nlattr_to_obj = dccp_timeout_nlattr_to_obj,
921 .obj_to_nlattr = dccp_timeout_obj_to_nlattr,
922 .nlattr_max = CTA_TIMEOUT_DCCP_MAX,
923 .obj_size = sizeof(unsigned int) * CT_DCCP_MAX,
924 .nla_policy = dccp_timeout_nla_policy,
925 },
926 #endif /* CONFIG_NF_CT_NETLINK_TIMEOUT */
927 .net_id = &dccp_net_id,
928 .init_net = dccp_init_net,
929 };
930
931 static __net_init int dccp_net_init(struct net *net)
932 {
933 int ret = 0;
934 ret = nf_conntrack_l4proto_register(net,
935 &dccp_proto4);
936 if (ret < 0) {
937 pr_err("nf_conntrack_l4proto_dccp4 :protocol register failed.\n");
938 goto out;
939 }
940 ret = nf_conntrack_l4proto_register(net,
941 &dccp_proto6);
942 if (ret < 0) {
943 pr_err("nf_conntrack_l4proto_dccp6 :protocol register failed.\n");
944 goto cleanup_dccp4;
945 }
946 return 0;
947 cleanup_dccp4:
948 nf_conntrack_l4proto_unregister(net,
949 &dccp_proto4);
950 out:
951 return ret;
952 }
953
954 static __net_exit void dccp_net_exit(struct net *net)
955 {
956 nf_conntrack_l4proto_unregister(net,
957 &dccp_proto6);
958 nf_conntrack_l4proto_unregister(net,
959 &dccp_proto4);
960 }
961
962 static struct pernet_operations dccp_net_ops = {
963 .init = dccp_net_init,
964 .exit = dccp_net_exit,
965 .id = &dccp_net_id,
966 .size = sizeof(struct dccp_net),
967 };
968
969 static int __init nf_conntrack_proto_dccp_init(void)
970 {
971 return register_pernet_subsys(&dccp_net_ops);
972 }
973
974 static void __exit nf_conntrack_proto_dccp_fini(void)
975 {
976 unregister_pernet_subsys(&dccp_net_ops);
977 }
978
979 module_init(nf_conntrack_proto_dccp_init);
980 module_exit(nf_conntrack_proto_dccp_fini);
981
982 MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
983 MODULE_DESCRIPTION("DCCP connection tracking protocol helper");
984 MODULE_LICENSE("GPL");
kernel source for telekom puls (alcatel/mediatek)