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Viewing changes to net/netfilter/nf_conntrack_proto_sctp.c

  • Committer: Package Import Robot
  • Author(s): Alessio Igor Bogani
  • Date: 2011-10-26 11:13:05 UTC
  • Revision ID: package-import@ubuntu.com-20111026111305-tz023xykf0i6eosh
Tags: upstream-3.2.0
Import upstream version 3.2.0

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net/netfilter/nf_conntrack_proto_sctp.c
 
1
/*
 
2
 * Connection tracking protocol helper module for SCTP.
 
3
 *
 
4
 * SCTP is defined in RFC 2960. References to various sections in this code
 
5
 * are to this RFC.
 
6
 *
 
7
 * This program is free software; you can redistribute it and/or modify
 
8
 * it under the terms of the GNU General Public License version 2 as
 
9
 * published by the Free Software Foundation.
 
10
 */
 
11
 
 
12
#include <linux/types.h>
 
13
#include <linux/timer.h>
 
14
#include <linux/netfilter.h>
 
15
#include <linux/module.h>
 
16
#include <linux/in.h>
 
17
#include <linux/ip.h>
 
18
#include <linux/sctp.h>
 
19
#include <linux/string.h>
 
20
#include <linux/seq_file.h>
 
21
#include <linux/spinlock.h>
 
22
#include <linux/interrupt.h>
 
23
 
 
24
#include <net/netfilter/nf_conntrack.h>
 
25
#include <net/netfilter/nf_conntrack_l4proto.h>
 
26
#include <net/netfilter/nf_conntrack_ecache.h>
 
27
 
 
28
/* FIXME: Examine ipfilter's timeouts and conntrack transitions more
 
29
   closely.  They're more complex. --RR
 
30
 
 
31
   And so for me for SCTP :D -Kiran */
 
32
 
 
33
static const char *const sctp_conntrack_names[] = {
 
34
        "NONE",
 
35
        "CLOSED",
 
36
        "COOKIE_WAIT",
 
37
        "COOKIE_ECHOED",
 
38
        "ESTABLISHED",
 
39
        "SHUTDOWN_SENT",
 
40
        "SHUTDOWN_RECD",
 
41
        "SHUTDOWN_ACK_SENT",
 
42
};
 
43
 
 
44
#define SECS  * HZ
 
45
#define MINS  * 60 SECS
 
46
#define HOURS * 60 MINS
 
47
#define DAYS  * 24 HOURS
 
48
 
 
49
static unsigned int sctp_timeouts[SCTP_CONNTRACK_MAX] __read_mostly = {
 
50
        [SCTP_CONNTRACK_CLOSED]                 = 10 SECS,
 
51
        [SCTP_CONNTRACK_COOKIE_WAIT]            = 3 SECS,
 
52
        [SCTP_CONNTRACK_COOKIE_ECHOED]          = 3 SECS,
 
53
        [SCTP_CONNTRACK_ESTABLISHED]            = 5 DAYS,
 
54
        [SCTP_CONNTRACK_SHUTDOWN_SENT]          = 300 SECS / 1000,
 
55
        [SCTP_CONNTRACK_SHUTDOWN_RECD]          = 300 SECS / 1000,
 
56
        [SCTP_CONNTRACK_SHUTDOWN_ACK_SENT]      = 3 SECS,
 
57
};
 
58
 
 
59
#define sNO SCTP_CONNTRACK_NONE
 
60
#define sCL SCTP_CONNTRACK_CLOSED
 
61
#define sCW SCTP_CONNTRACK_COOKIE_WAIT
 
62
#define sCE SCTP_CONNTRACK_COOKIE_ECHOED
 
63
#define sES SCTP_CONNTRACK_ESTABLISHED
 
64
#define sSS SCTP_CONNTRACK_SHUTDOWN_SENT
 
65
#define sSR SCTP_CONNTRACK_SHUTDOWN_RECD
 
66
#define sSA SCTP_CONNTRACK_SHUTDOWN_ACK_SENT
 
67
#define sIV SCTP_CONNTRACK_MAX
 
68
 
 
69
/*
 
70
        These are the descriptions of the states:
 
71
 
 
72
NOTE: These state names are tantalizingly similar to the states of an
 
73
SCTP endpoint. But the interpretation of the states is a little different,
 
74
considering that these are the states of the connection and not of an end
 
75
point. Please note the subtleties. -Kiran
 
76
 
 
77
NONE              - Nothing so far.
 
78
COOKIE WAIT       - We have seen an INIT chunk in the original direction, or also
 
79
                    an INIT_ACK chunk in the reply direction.
 
80
COOKIE ECHOED     - We have seen a COOKIE_ECHO chunk in the original direction.
 
81
ESTABLISHED       - We have seen a COOKIE_ACK in the reply direction.
 
82
SHUTDOWN_SENT     - We have seen a SHUTDOWN chunk in the original direction.
 
83
SHUTDOWN_RECD     - We have seen a SHUTDOWN chunk in the reply directoin.
 
84
SHUTDOWN_ACK_SENT - We have seen a SHUTDOWN_ACK chunk in the direction opposite
 
85
                    to that of the SHUTDOWN chunk.
 
86
CLOSED            - We have seen a SHUTDOWN_COMPLETE chunk in the direction of
 
87
                    the SHUTDOWN chunk. Connection is closed.
 
88
*/
 
89
 
 
90
/* TODO
 
91
 - I have assumed that the first INIT is in the original direction.
 
92
 This messes things when an INIT comes in the reply direction in CLOSED
 
93
 state.
 
94
 - Check the error type in the reply dir before transitioning from
 
95
cookie echoed to closed.
 
96
 - Sec 5.2.4 of RFC 2960
 
97
 - Multi Homing support.
 
98
*/
 
99
 
 
100
/* SCTP conntrack state transitions */
 
101
static const u8 sctp_conntracks[2][9][SCTP_CONNTRACK_MAX] = {
 
102
        {
 
103
/*      ORIGINAL        */
 
104
/*                  sNO, sCL, sCW, sCE, sES, sSS, sSR, sSA */
 
105
/* init         */ {sCW, sCW, sCW, sCE, sES, sSS, sSR, sSA},
 
106
/* init_ack     */ {sCL, sCL, sCW, sCE, sES, sSS, sSR, sSA},
 
107
/* abort        */ {sCL, sCL, sCL, sCL, sCL, sCL, sCL, sCL},
 
108
/* shutdown     */ {sCL, sCL, sCW, sCE, sSS, sSS, sSR, sSA},
 
109
/* shutdown_ack */ {sSA, sCL, sCW, sCE, sES, sSA, sSA, sSA},
 
110
/* error        */ {sCL, sCL, sCW, sCE, sES, sSS, sSR, sSA},/* Can't have Stale cookie*/
 
111
/* cookie_echo  */ {sCL, sCL, sCE, sCE, sES, sSS, sSR, sSA},/* 5.2.4 - Big TODO */
 
112
/* cookie_ack   */ {sCL, sCL, sCW, sCE, sES, sSS, sSR, sSA},/* Can't come in orig dir */
 
113
/* shutdown_comp*/ {sCL, sCL, sCW, sCE, sES, sSS, sSR, sCL}
 
114
        },
 
115
        {
 
116
/*      REPLY   */
 
117
/*                  sNO, sCL, sCW, sCE, sES, sSS, sSR, sSA */
 
118
/* init         */ {sIV, sCL, sCW, sCE, sES, sSS, sSR, sSA},/* INIT in sCL Big TODO */
 
119
/* init_ack     */ {sIV, sCL, sCW, sCE, sES, sSS, sSR, sSA},
 
120
/* abort        */ {sIV, sCL, sCL, sCL, sCL, sCL, sCL, sCL},
 
121
/* shutdown     */ {sIV, sCL, sCW, sCE, sSR, sSS, sSR, sSA},
 
122
/* shutdown_ack */ {sIV, sCL, sCW, sCE, sES, sSA, sSA, sSA},
 
123
/* error        */ {sIV, sCL, sCW, sCL, sES, sSS, sSR, sSA},
 
124
/* cookie_echo  */ {sIV, sCL, sCW, sCE, sES, sSS, sSR, sSA},/* Can't come in reply dir */
 
125
/* cookie_ack   */ {sIV, sCL, sCW, sES, sES, sSS, sSR, sSA},
 
126
/* shutdown_comp*/ {sIV, sCL, sCW, sCE, sES, sSS, sSR, sCL}
 
127
        }
 
128
};
 
129
 
 
130
static bool sctp_pkt_to_tuple(const struct sk_buff *skb, unsigned int dataoff,
 
131
                              struct nf_conntrack_tuple *tuple)
 
132
{
 
133
        const struct sctphdr *hp;
 
134
        struct sctphdr _hdr;
 
135
 
 
136
        /* Actually only need first 8 bytes. */
 
137
        hp = skb_header_pointer(skb, dataoff, 8, &_hdr);
 
138
        if (hp == NULL)
 
139
                return false;
 
140
 
 
141
        tuple->src.u.sctp.port = hp->source;
 
142
        tuple->dst.u.sctp.port = hp->dest;
 
143
        return true;
 
144
}
 
145
 
 
146
static bool sctp_invert_tuple(struct nf_conntrack_tuple *tuple,
 
147
                              const struct nf_conntrack_tuple *orig)
 
148
{
 
149
        tuple->src.u.sctp.port = orig->dst.u.sctp.port;
 
150
        tuple->dst.u.sctp.port = orig->src.u.sctp.port;
 
151
        return true;
 
152
}
 
153
 
 
154
/* Print out the per-protocol part of the tuple. */
 
155
static int sctp_print_tuple(struct seq_file *s,
 
156
                            const struct nf_conntrack_tuple *tuple)
 
157
{
 
158
        return seq_printf(s, "sport=%hu dport=%hu ",
 
159
                          ntohs(tuple->src.u.sctp.port),
 
160
                          ntohs(tuple->dst.u.sctp.port));
 
161
}
 
162
 
 
163
/* Print out the private part of the conntrack. */
 
164
static int sctp_print_conntrack(struct seq_file *s, struct nf_conn *ct)
 
165
{
 
166
        enum sctp_conntrack state;
 
167
 
 
168
        spin_lock_bh(&ct->lock);
 
169
        state = ct->proto.sctp.state;
 
170
        spin_unlock_bh(&ct->lock);
 
171
 
 
172
        return seq_printf(s, "%s ", sctp_conntrack_names[state]);
 
173
}
 
174
 
 
175
#define for_each_sctp_chunk(skb, sch, _sch, offset, dataoff, count)     \
 
176
for ((offset) = (dataoff) + sizeof(sctp_sctphdr_t), (count) = 0;        \
 
177
        (offset) < (skb)->len &&                                        \
 
178
        ((sch) = skb_header_pointer((skb), (offset), sizeof(_sch), &(_sch)));   \
 
179
        (offset) += (ntohs((sch)->length) + 3) & ~3, (count)++)
 
180
 
 
181
/* Some validity checks to make sure the chunks are fine */
 
182
static int do_basic_checks(struct nf_conn *ct,
 
183
                           const struct sk_buff *skb,
 
184
                           unsigned int dataoff,
 
185
                           unsigned long *map)
 
186
{
 
187
        u_int32_t offset, count;
 
188
        sctp_chunkhdr_t _sch, *sch;
 
189
        int flag;
 
190
 
 
191
        flag = 0;
 
192
 
 
193
        for_each_sctp_chunk (skb, sch, _sch, offset, dataoff, count) {
 
194
                pr_debug("Chunk Num: %d  Type: %d\n", count, sch->type);
 
195
 
 
196
                if (sch->type == SCTP_CID_INIT ||
 
197
                    sch->type == SCTP_CID_INIT_ACK ||
 
198
                    sch->type == SCTP_CID_SHUTDOWN_COMPLETE)
 
199
                        flag = 1;
 
200
 
 
201
                /*
 
202
                 * Cookie Ack/Echo chunks not the first OR
 
203
                 * Init / Init Ack / Shutdown compl chunks not the only chunks
 
204
                 * OR zero-length.
 
205
                 */
 
206
                if (((sch->type == SCTP_CID_COOKIE_ACK ||
 
207
                      sch->type == SCTP_CID_COOKIE_ECHO ||
 
208
                      flag) &&
 
209
                     count != 0) || !sch->length) {
 
210
                        pr_debug("Basic checks failed\n");
 
211
                        return 1;
 
212
                }
 
213
 
 
214
                if (map)
 
215
                        set_bit(sch->type, map);
 
216
        }
 
217
 
 
218
        pr_debug("Basic checks passed\n");
 
219
        return count == 0;
 
220
}
 
221
 
 
222
static int sctp_new_state(enum ip_conntrack_dir dir,
 
223
                          enum sctp_conntrack cur_state,
 
224
                          int chunk_type)
 
225
{
 
226
        int i;
 
227
 
 
228
        pr_debug("Chunk type: %d\n", chunk_type);
 
229
 
 
230
        switch (chunk_type) {
 
231
        case SCTP_CID_INIT:
 
232
                pr_debug("SCTP_CID_INIT\n");
 
233
                i = 0;
 
234
                break;
 
235
        case SCTP_CID_INIT_ACK:
 
236
                pr_debug("SCTP_CID_INIT_ACK\n");
 
237
                i = 1;
 
238
                break;
 
239
        case SCTP_CID_ABORT:
 
240
                pr_debug("SCTP_CID_ABORT\n");
 
241
                i = 2;
 
242
                break;
 
243
        case SCTP_CID_SHUTDOWN:
 
244
                pr_debug("SCTP_CID_SHUTDOWN\n");
 
245
                i = 3;
 
246
                break;
 
247
        case SCTP_CID_SHUTDOWN_ACK:
 
248
                pr_debug("SCTP_CID_SHUTDOWN_ACK\n");
 
249
                i = 4;
 
250
                break;
 
251
        case SCTP_CID_ERROR:
 
252
                pr_debug("SCTP_CID_ERROR\n");
 
253
                i = 5;
 
254
                break;
 
255
        case SCTP_CID_COOKIE_ECHO:
 
256
                pr_debug("SCTP_CID_COOKIE_ECHO\n");
 
257
                i = 6;
 
258
                break;
 
259
        case SCTP_CID_COOKIE_ACK:
 
260
                pr_debug("SCTP_CID_COOKIE_ACK\n");
 
261
                i = 7;
 
262
                break;
 
263
        case SCTP_CID_SHUTDOWN_COMPLETE:
 
264
                pr_debug("SCTP_CID_SHUTDOWN_COMPLETE\n");
 
265
                i = 8;
 
266
                break;
 
267
        default:
 
268
                /* Other chunks like DATA, SACK, HEARTBEAT and
 
269
                its ACK do not cause a change in state */
 
270
                pr_debug("Unknown chunk type, Will stay in %s\n",
 
271
                         sctp_conntrack_names[cur_state]);
 
272
                return cur_state;
 
273
        }
 
274
 
 
275
        pr_debug("dir: %d   cur_state: %s  chunk_type: %d  new_state: %s\n",
 
276
                 dir, sctp_conntrack_names[cur_state], chunk_type,
 
277
                 sctp_conntrack_names[sctp_conntracks[dir][i][cur_state]]);
 
278
 
 
279
        return sctp_conntracks[dir][i][cur_state];
 
280
}
 
281
 
 
282
/* Returns verdict for packet, or -NF_ACCEPT for invalid. */
 
283
static int sctp_packet(struct nf_conn *ct,
 
284
                       const struct sk_buff *skb,
 
285
                       unsigned int dataoff,
 
286
                       enum ip_conntrack_info ctinfo,
 
287
                       u_int8_t pf,
 
288
                       unsigned int hooknum)
 
289
{
 
290
        enum sctp_conntrack new_state, old_state;
 
291
        enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo);
 
292
        const struct sctphdr *sh;
 
293
        struct sctphdr _sctph;
 
294
        const struct sctp_chunkhdr *sch;
 
295
        struct sctp_chunkhdr _sch;
 
296
        u_int32_t offset, count;
 
297
        unsigned long map[256 / sizeof(unsigned long)] = { 0 };
 
298
 
 
299
        sh = skb_header_pointer(skb, dataoff, sizeof(_sctph), &_sctph);
 
300
        if (sh == NULL)
 
301
                goto out;
 
302
 
 
303
        if (do_basic_checks(ct, skb, dataoff, map) != 0)
 
304
                goto out;
 
305
 
 
306
        /* Check the verification tag (Sec 8.5) */
 
307
        if (!test_bit(SCTP_CID_INIT, map) &&
 
308
            !test_bit(SCTP_CID_SHUTDOWN_COMPLETE, map) &&
 
309
            !test_bit(SCTP_CID_COOKIE_ECHO, map) &&
 
310
            !test_bit(SCTP_CID_ABORT, map) &&
 
311
            !test_bit(SCTP_CID_SHUTDOWN_ACK, map) &&
 
312
            sh->vtag != ct->proto.sctp.vtag[dir]) {
 
313
                pr_debug("Verification tag check failed\n");
 
314
                goto out;
 
315
        }
 
316
 
 
317
        old_state = new_state = SCTP_CONNTRACK_NONE;
 
318
        spin_lock_bh(&ct->lock);
 
319
        for_each_sctp_chunk (skb, sch, _sch, offset, dataoff, count) {
 
320
                /* Special cases of Verification tag check (Sec 8.5.1) */
 
321
                if (sch->type == SCTP_CID_INIT) {
 
322
                        /* Sec 8.5.1 (A) */
 
323
                        if (sh->vtag != 0)
 
324
                                goto out_unlock;
 
325
                } else if (sch->type == SCTP_CID_ABORT) {
 
326
                        /* Sec 8.5.1 (B) */
 
327
                        if (sh->vtag != ct->proto.sctp.vtag[dir] &&
 
328
                            sh->vtag != ct->proto.sctp.vtag[!dir])
 
329
                                goto out_unlock;
 
330
                } else if (sch->type == SCTP_CID_SHUTDOWN_COMPLETE) {
 
331
                        /* Sec 8.5.1 (C) */
 
332
                        if (sh->vtag != ct->proto.sctp.vtag[dir] &&
 
333
                            sh->vtag != ct->proto.sctp.vtag[!dir] &&
 
334
                            sch->flags & SCTP_CHUNK_FLAG_T)
 
335
                                goto out_unlock;
 
336
                } else if (sch->type == SCTP_CID_COOKIE_ECHO) {
 
337
                        /* Sec 8.5.1 (D) */
 
338
                        if (sh->vtag != ct->proto.sctp.vtag[dir])
 
339
                                goto out_unlock;
 
340
                }
 
341
 
 
342
                old_state = ct->proto.sctp.state;
 
343
                new_state = sctp_new_state(dir, old_state, sch->type);
 
344
 
 
345
                /* Invalid */
 
346
                if (new_state == SCTP_CONNTRACK_MAX) {
 
347
                        pr_debug("nf_conntrack_sctp: Invalid dir=%i ctype=%u "
 
348
                                 "conntrack=%u\n",
 
349
                                 dir, sch->type, old_state);
 
350
                        goto out_unlock;
 
351
                }
 
352
 
 
353
                /* If it is an INIT or an INIT ACK note down the vtag */
 
354
                if (sch->type == SCTP_CID_INIT ||
 
355
                    sch->type == SCTP_CID_INIT_ACK) {
 
356
                        sctp_inithdr_t _inithdr, *ih;
 
357
 
 
358
                        ih = skb_header_pointer(skb, offset + sizeof(sctp_chunkhdr_t),
 
359
                                                sizeof(_inithdr), &_inithdr);
 
360
                        if (ih == NULL)
 
361
                                goto out_unlock;
 
362
                        pr_debug("Setting vtag %x for dir %d\n",
 
363
                                 ih->init_tag, !dir);
 
364
                        ct->proto.sctp.vtag[!dir] = ih->init_tag;
 
365
                }
 
366
 
 
367
                ct->proto.sctp.state = new_state;
 
368
                if (old_state != new_state)
 
369
                        nf_conntrack_event_cache(IPCT_PROTOINFO, ct);
 
370
        }
 
371
        spin_unlock_bh(&ct->lock);
 
372
 
 
373
        nf_ct_refresh_acct(ct, ctinfo, skb, sctp_timeouts[new_state]);
 
374
 
 
375
        if (old_state == SCTP_CONNTRACK_COOKIE_ECHOED &&
 
376
            dir == IP_CT_DIR_REPLY &&
 
377
            new_state == SCTP_CONNTRACK_ESTABLISHED) {
 
378
                pr_debug("Setting assured bit\n");
 
379
                set_bit(IPS_ASSURED_BIT, &ct->status);
 
380
                nf_conntrack_event_cache(IPCT_ASSURED, ct);
 
381
        }
 
382
 
 
383
        return NF_ACCEPT;
 
384
 
 
385
out_unlock:
 
386
        spin_unlock_bh(&ct->lock);
 
387
out:
 
388
        return -NF_ACCEPT;
 
389
}
 
390
 
 
391
/* Called when a new connection for this protocol found. */
 
392
static bool sctp_new(struct nf_conn *ct, const struct sk_buff *skb,
 
393
                     unsigned int dataoff)
 
394
{
 
395
        enum sctp_conntrack new_state;
 
396
        const struct sctphdr *sh;
 
397
        struct sctphdr _sctph;
 
398
        const struct sctp_chunkhdr *sch;
 
399
        struct sctp_chunkhdr _sch;
 
400
        u_int32_t offset, count;
 
401
        unsigned long map[256 / sizeof(unsigned long)] = { 0 };
 
402
 
 
403
        sh = skb_header_pointer(skb, dataoff, sizeof(_sctph), &_sctph);
 
404
        if (sh == NULL)
 
405
                return false;
 
406
 
 
407
        if (do_basic_checks(ct, skb, dataoff, map) != 0)
 
408
                return false;
 
409
 
 
410
        /* If an OOTB packet has any of these chunks discard (Sec 8.4) */
 
411
        if (test_bit(SCTP_CID_ABORT, map) ||
 
412
            test_bit(SCTP_CID_SHUTDOWN_COMPLETE, map) ||
 
413
            test_bit(SCTP_CID_COOKIE_ACK, map))
 
414
                return false;
 
415
 
 
416
        memset(&ct->proto.sctp, 0, sizeof(ct->proto.sctp));
 
417
        new_state = SCTP_CONNTRACK_MAX;
 
418
        for_each_sctp_chunk (skb, sch, _sch, offset, dataoff, count) {
 
419
                /* Don't need lock here: this conntrack not in circulation yet */
 
420
                new_state = sctp_new_state(IP_CT_DIR_ORIGINAL,
 
421
                                           SCTP_CONNTRACK_NONE, sch->type);
 
422
 
 
423
                /* Invalid: delete conntrack */
 
424
                if (new_state == SCTP_CONNTRACK_NONE ||
 
425
                    new_state == SCTP_CONNTRACK_MAX) {
 
426
                        pr_debug("nf_conntrack_sctp: invalid new deleting.\n");
 
427
                        return false;
 
428
                }
 
429
 
 
430
                /* Copy the vtag into the state info */
 
431
                if (sch->type == SCTP_CID_INIT) {
 
432
                        if (sh->vtag == 0) {
 
433
                                sctp_inithdr_t _inithdr, *ih;
 
434
 
 
435
                                ih = skb_header_pointer(skb, offset + sizeof(sctp_chunkhdr_t),
 
436
                                                        sizeof(_inithdr), &_inithdr);
 
437
                                if (ih == NULL)
 
438
                                        return false;
 
439
 
 
440
                                pr_debug("Setting vtag %x for new conn\n",
 
441
                                         ih->init_tag);
 
442
 
 
443
                                ct->proto.sctp.vtag[IP_CT_DIR_REPLY] =
 
444
                                                                ih->init_tag;
 
445
                        } else {
 
446
                                /* Sec 8.5.1 (A) */
 
447
                                return false;
 
448
                        }
 
449
                }
 
450
                /* If it is a shutdown ack OOTB packet, we expect a return
 
451
                   shutdown complete, otherwise an ABORT Sec 8.4 (5) and (8) */
 
452
                else {
 
453
                        pr_debug("Setting vtag %x for new conn OOTB\n",
 
454
                                 sh->vtag);
 
455
                        ct->proto.sctp.vtag[IP_CT_DIR_REPLY] = sh->vtag;
 
456
                }
 
457
 
 
458
                ct->proto.sctp.state = new_state;
 
459
        }
 
460
 
 
461
        return true;
 
462
}
 
463
 
 
464
#if defined(CONFIG_NF_CT_NETLINK) || defined(CONFIG_NF_CT_NETLINK_MODULE)
 
465
 
 
466
#include <linux/netfilter/nfnetlink.h>
 
467
#include <linux/netfilter/nfnetlink_conntrack.h>
 
468
 
 
469
static int sctp_to_nlattr(struct sk_buff *skb, struct nlattr *nla,
 
470
                          struct nf_conn *ct)
 
471
{
 
472
        struct nlattr *nest_parms;
 
473
 
 
474
        spin_lock_bh(&ct->lock);
 
475
        nest_parms = nla_nest_start(skb, CTA_PROTOINFO_SCTP | NLA_F_NESTED);
 
476
        if (!nest_parms)
 
477
                goto nla_put_failure;
 
478
 
 
479
        NLA_PUT_U8(skb, CTA_PROTOINFO_SCTP_STATE, ct->proto.sctp.state);
 
480
 
 
481
        NLA_PUT_BE32(skb,
 
482
                     CTA_PROTOINFO_SCTP_VTAG_ORIGINAL,
 
483
                     ct->proto.sctp.vtag[IP_CT_DIR_ORIGINAL]);
 
484
 
 
485
        NLA_PUT_BE32(skb,
 
486
                     CTA_PROTOINFO_SCTP_VTAG_REPLY,
 
487
                     ct->proto.sctp.vtag[IP_CT_DIR_REPLY]);
 
488
 
 
489
        spin_unlock_bh(&ct->lock);
 
490
 
 
491
        nla_nest_end(skb, nest_parms);
 
492
 
 
493
        return 0;
 
494
 
 
495
nla_put_failure:
 
496
        spin_unlock_bh(&ct->lock);
 
497
        return -1;
 
498
}
 
499
 
 
500
static const struct nla_policy sctp_nla_policy[CTA_PROTOINFO_SCTP_MAX+1] = {
 
501
        [CTA_PROTOINFO_SCTP_STATE]          = { .type = NLA_U8 },
 
502
        [CTA_PROTOINFO_SCTP_VTAG_ORIGINAL]  = { .type = NLA_U32 },
 
503
        [CTA_PROTOINFO_SCTP_VTAG_REPLY]     = { .type = NLA_U32 },
 
504
};
 
505
 
 
506
static int nlattr_to_sctp(struct nlattr *cda[], struct nf_conn *ct)
 
507
{
 
508
        struct nlattr *attr = cda[CTA_PROTOINFO_SCTP];
 
509
        struct nlattr *tb[CTA_PROTOINFO_SCTP_MAX+1];
 
510
        int err;
 
511
 
 
512
        /* updates may not contain the internal protocol info, skip parsing */
 
513
        if (!attr)
 
514
                return 0;
 
515
 
 
516
        err = nla_parse_nested(tb,
 
517
                               CTA_PROTOINFO_SCTP_MAX,
 
518
                               attr,
 
519
                               sctp_nla_policy);
 
520
        if (err < 0)
 
521
                return err;
 
522
 
 
523
        if (!tb[CTA_PROTOINFO_SCTP_STATE] ||
 
524
            !tb[CTA_PROTOINFO_SCTP_VTAG_ORIGINAL] ||
 
525
            !tb[CTA_PROTOINFO_SCTP_VTAG_REPLY])
 
526
                return -EINVAL;
 
527
 
 
528
        spin_lock_bh(&ct->lock);
 
529
        ct->proto.sctp.state = nla_get_u8(tb[CTA_PROTOINFO_SCTP_STATE]);
 
530
        ct->proto.sctp.vtag[IP_CT_DIR_ORIGINAL] =
 
531
                nla_get_be32(tb[CTA_PROTOINFO_SCTP_VTAG_ORIGINAL]);
 
532
        ct->proto.sctp.vtag[IP_CT_DIR_REPLY] =
 
533
                nla_get_be32(tb[CTA_PROTOINFO_SCTP_VTAG_REPLY]);
 
534
        spin_unlock_bh(&ct->lock);
 
535
 
 
536
        return 0;
 
537
}
 
538
 
 
539
static int sctp_nlattr_size(void)
 
540
{
 
541
        return nla_total_size(0)        /* CTA_PROTOINFO_SCTP */
 
542
                + nla_policy_len(sctp_nla_policy, CTA_PROTOINFO_SCTP_MAX + 1);
 
543
}
 
544
#endif
 
545
 
 
546
#ifdef CONFIG_SYSCTL
 
547
static unsigned int sctp_sysctl_table_users;
 
548
static struct ctl_table_header *sctp_sysctl_header;
 
549
static struct ctl_table sctp_sysctl_table[] = {
 
550
        {
 
551
                .procname       = "nf_conntrack_sctp_timeout_closed",
 
552
                .data           = &sctp_timeouts[SCTP_CONNTRACK_CLOSED],
 
553
                .maxlen         = sizeof(unsigned int),
 
554
                .mode           = 0644,
 
555
                .proc_handler   = proc_dointvec_jiffies,
 
556
        },
 
557
        {
 
558
                .procname       = "nf_conntrack_sctp_timeout_cookie_wait",
 
559
                .data           = &sctp_timeouts[SCTP_CONNTRACK_COOKIE_WAIT],
 
560
                .maxlen         = sizeof(unsigned int),
 
561
                .mode           = 0644,
 
562
                .proc_handler   = proc_dointvec_jiffies,
 
563
        },
 
564
        {
 
565
                .procname       = "nf_conntrack_sctp_timeout_cookie_echoed",
 
566
                .data           = &sctp_timeouts[SCTP_CONNTRACK_COOKIE_ECHOED],
 
567
                .maxlen         = sizeof(unsigned int),
 
568
                .mode           = 0644,
 
569
                .proc_handler   = proc_dointvec_jiffies,
 
570
        },
 
571
        {
 
572
                .procname       = "nf_conntrack_sctp_timeout_established",
 
573
                .data           = &sctp_timeouts[SCTP_CONNTRACK_ESTABLISHED],
 
574
                .maxlen         = sizeof(unsigned int),
 
575
                .mode           = 0644,
 
576
                .proc_handler   = proc_dointvec_jiffies,
 
577
        },
 
578
        {
 
579
                .procname       = "nf_conntrack_sctp_timeout_shutdown_sent",
 
580
                .data           = &sctp_timeouts[SCTP_CONNTRACK_SHUTDOWN_SENT],
 
581
                .maxlen         = sizeof(unsigned int),
 
582
                .mode           = 0644,
 
583
                .proc_handler   = proc_dointvec_jiffies,
 
584
        },
 
585
        {
 
586
                .procname       = "nf_conntrack_sctp_timeout_shutdown_recd",
 
587
                .data           = &sctp_timeouts[SCTP_CONNTRACK_SHUTDOWN_RECD],
 
588
                .maxlen         = sizeof(unsigned int),
 
589
                .mode           = 0644,
 
590
                .proc_handler   = proc_dointvec_jiffies,
 
591
        },
 
592
        {
 
593
                .procname       = "nf_conntrack_sctp_timeout_shutdown_ack_sent",
 
594
                .data           = &sctp_timeouts[SCTP_CONNTRACK_SHUTDOWN_ACK_SENT],
 
595
                .maxlen         = sizeof(unsigned int),
 
596
                .mode           = 0644,
 
597
                .proc_handler   = proc_dointvec_jiffies,
 
598
        },
 
599
        { }
 
600
};
 
601
 
 
602
#ifdef CONFIG_NF_CONNTRACK_PROC_COMPAT
 
603
static struct ctl_table sctp_compat_sysctl_table[] = {
 
604
        {
 
605
                .procname       = "ip_conntrack_sctp_timeout_closed",
 
606
                .data           = &sctp_timeouts[SCTP_CONNTRACK_CLOSED],
 
607
                .maxlen         = sizeof(unsigned int),
 
608
                .mode           = 0644,
 
609
                .proc_handler   = proc_dointvec_jiffies,
 
610
        },
 
611
        {
 
612
                .procname       = "ip_conntrack_sctp_timeout_cookie_wait",
 
613
                .data           = &sctp_timeouts[SCTP_CONNTRACK_COOKIE_WAIT],
 
614
                .maxlen         = sizeof(unsigned int),
 
615
                .mode           = 0644,
 
616
                .proc_handler   = proc_dointvec_jiffies,
 
617
        },
 
618
        {
 
619
                .procname       = "ip_conntrack_sctp_timeout_cookie_echoed",
 
620
                .data           = &sctp_timeouts[SCTP_CONNTRACK_COOKIE_ECHOED],
 
621
                .maxlen         = sizeof(unsigned int),
 
622
                .mode           = 0644,
 
623
                .proc_handler   = proc_dointvec_jiffies,
 
624
        },
 
625
        {
 
626
                .procname       = "ip_conntrack_sctp_timeout_established",
 
627
                .data           = &sctp_timeouts[SCTP_CONNTRACK_ESTABLISHED],
 
628
                .maxlen         = sizeof(unsigned int),
 
629
                .mode           = 0644,
 
630
                .proc_handler   = proc_dointvec_jiffies,
 
631
        },
 
632
        {
 
633
                .procname       = "ip_conntrack_sctp_timeout_shutdown_sent",
 
634
                .data           = &sctp_timeouts[SCTP_CONNTRACK_SHUTDOWN_SENT],
 
635
                .maxlen         = sizeof(unsigned int),
 
636
                .mode           = 0644,
 
637
                .proc_handler   = proc_dointvec_jiffies,
 
638
        },
 
639
        {
 
640
                .procname       = "ip_conntrack_sctp_timeout_shutdown_recd",
 
641
                .data           = &sctp_timeouts[SCTP_CONNTRACK_SHUTDOWN_RECD],
 
642
                .maxlen         = sizeof(unsigned int),
 
643
                .mode           = 0644,
 
644
                .proc_handler   = proc_dointvec_jiffies,
 
645
        },
 
646
        {
 
647
                .procname       = "ip_conntrack_sctp_timeout_shutdown_ack_sent",
 
648
                .data           = &sctp_timeouts[SCTP_CONNTRACK_SHUTDOWN_ACK_SENT],
 
649
                .maxlen         = sizeof(unsigned int),
 
650
                .mode           = 0644,
 
651
                .proc_handler   = proc_dointvec_jiffies,
 
652
        },
 
653
        { }
 
654
};
 
655
#endif /* CONFIG_NF_CONNTRACK_PROC_COMPAT */
 
656
#endif
 
657
 
 
658
static struct nf_conntrack_l4proto nf_conntrack_l4proto_sctp4 __read_mostly = {
 
659
        .l3proto                = PF_INET,
 
660
        .l4proto                = IPPROTO_SCTP,
 
661
        .name                   = "sctp",
 
662
        .pkt_to_tuple           = sctp_pkt_to_tuple,
 
663
        .invert_tuple           = sctp_invert_tuple,
 
664
        .print_tuple            = sctp_print_tuple,
 
665
        .print_conntrack        = sctp_print_conntrack,
 
666
        .packet                 = sctp_packet,
 
667
        .new                    = sctp_new,
 
668
        .me                     = THIS_MODULE,
 
669
#if defined(CONFIG_NF_CT_NETLINK) || defined(CONFIG_NF_CT_NETLINK_MODULE)
 
670
        .to_nlattr              = sctp_to_nlattr,
 
671
        .nlattr_size            = sctp_nlattr_size,
 
672
        .from_nlattr            = nlattr_to_sctp,
 
673
        .tuple_to_nlattr        = nf_ct_port_tuple_to_nlattr,
 
674
        .nlattr_tuple_size      = nf_ct_port_nlattr_tuple_size,
 
675
        .nlattr_to_tuple        = nf_ct_port_nlattr_to_tuple,
 
676
        .nla_policy             = nf_ct_port_nla_policy,
 
677
#endif
 
678
#ifdef CONFIG_SYSCTL
 
679
        .ctl_table_users        = &sctp_sysctl_table_users,
 
680
        .ctl_table_header       = &sctp_sysctl_header,
 
681
        .ctl_table              = sctp_sysctl_table,
 
682
#ifdef CONFIG_NF_CONNTRACK_PROC_COMPAT
 
683
        .ctl_compat_table       = sctp_compat_sysctl_table,
 
684
#endif
 
685
#endif
 
686
};
 
687
 
 
688
static struct nf_conntrack_l4proto nf_conntrack_l4proto_sctp6 __read_mostly = {
 
689
        .l3proto                = PF_INET6,
 
690
        .l4proto                = IPPROTO_SCTP,
 
691
        .name                   = "sctp",
 
692
        .pkt_to_tuple           = sctp_pkt_to_tuple,
 
693
        .invert_tuple           = sctp_invert_tuple,
 
694
        .print_tuple            = sctp_print_tuple,
 
695
        .print_conntrack        = sctp_print_conntrack,
 
696
        .packet                 = sctp_packet,
 
697
        .new                    = sctp_new,
 
698
        .me                     = THIS_MODULE,
 
699
#if defined(CONFIG_NF_CT_NETLINK) || defined(CONFIG_NF_CT_NETLINK_MODULE)
 
700
        .to_nlattr              = sctp_to_nlattr,
 
701
        .nlattr_size            = sctp_nlattr_size,
 
702
        .from_nlattr            = nlattr_to_sctp,
 
703
        .tuple_to_nlattr        = nf_ct_port_tuple_to_nlattr,
 
704
        .nlattr_tuple_size      = nf_ct_port_nlattr_tuple_size,
 
705
        .nlattr_to_tuple        = nf_ct_port_nlattr_to_tuple,
 
706
        .nla_policy             = nf_ct_port_nla_policy,
 
707
#endif
 
708
#ifdef CONFIG_SYSCTL
 
709
        .ctl_table_users        = &sctp_sysctl_table_users,
 
710
        .ctl_table_header       = &sctp_sysctl_header,
 
711
        .ctl_table              = sctp_sysctl_table,
 
712
#endif
 
713
};
 
714
 
 
715
static int __init nf_conntrack_proto_sctp_init(void)
 
716
{
 
717
        int ret;
 
718
 
 
719
        ret = nf_conntrack_l4proto_register(&nf_conntrack_l4proto_sctp4);
 
720
        if (ret) {
 
721
                pr_err("nf_conntrack_l4proto_sctp4: protocol register failed\n");
 
722
                goto out;
 
723
        }
 
724
        ret = nf_conntrack_l4proto_register(&nf_conntrack_l4proto_sctp6);
 
725
        if (ret) {
 
726
                pr_err("nf_conntrack_l4proto_sctp6: protocol register failed\n");
 
727
                goto cleanup_sctp4;
 
728
        }
 
729
 
 
730
        return ret;
 
731
 
 
732
 cleanup_sctp4:
 
733
        nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_sctp4);
 
734
 out:
 
735
        return ret;
 
736
}
 
737
 
 
738
static void __exit nf_conntrack_proto_sctp_fini(void)
 
739
{
 
740
        nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_sctp6);
 
741
        nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_sctp4);
 
742
}
 
743
 
 
744
module_init(nf_conntrack_proto_sctp_init);
 
745
module_exit(nf_conntrack_proto_sctp_fini);
 
746
 
 
747
MODULE_LICENSE("GPL");
 
748
MODULE_AUTHOR("Kiran Kumar Immidi");
 
749
MODULE_DESCRIPTION("Netfilter connection tracking protocol helper for SCTP");
 
750
MODULE_ALIAS("ip_conntrack_proto_sctp");