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allow coexistance of N build and AC build.
[tomato.git] / release / src-rt-6.x / linux / linux-2.6 / net / netfilter / xt_hashlimit.c
blobae503e79cdb3bdc0a58829480656d355d376b655
1 /* iptables match extension to limit the number of packets per second
2 * seperately for each hashbucket (sourceip/sourceport/dstip/dstport)
3 *
4 * (C) 2003-2004 by Harald Welte <laforge@netfilter.org>
5 *
6 * $Id: ipt_hashlimit.c 3244 2004-10-20 16:24:29Z laforge@netfilter.org $
7 *
8 * Development of this code was funded by Astaro AG, http://www.astaro.com/
9 */
10 #include <linux/module.h>
11 #include <linux/spinlock.h>
12 #include <linux/random.h>
13 #include <linux/jhash.h>
14 #include <linux/slab.h>
15 #include <linux/vmalloc.h>
16 #include <linux/proc_fs.h>
17 #include <linux/seq_file.h>
18 #include <linux/list.h>
19 #include <linux/skbuff.h>
20 #include <linux/mm.h>
21 #include <linux/in.h>
22 #include <linux/ip.h>
23 #if defined(CONFIG_IP6_NF_IPTABLES) || defined(CONFIG_IP6_NF_IPTABLES_MODULE)
24 #include <linux/ipv6.h>
25 #include <net/ipv6.h>
26 #endif
27
28 #include <linux/netfilter/x_tables.h>
29 #include <linux/netfilter_ipv4/ip_tables.h>
30 #include <linux/netfilter_ipv6/ip6_tables.h>
31 #include <linux/netfilter/xt_hashlimit.h>
32 #include <linux/mutex.h>
33
34 MODULE_LICENSE("GPL");
35 MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");
36 MODULE_DESCRIPTION("iptables match for limiting per hash-bucket");
37 MODULE_ALIAS("ipt_hashlimit");
38 MODULE_ALIAS("ip6t_hashlimit");
39
40 /* need to declare this at the top */
41 static struct proc_dir_entry *hashlimit_procdir4;
42 static struct proc_dir_entry *hashlimit_procdir6;
43 static const struct file_operations dl_file_ops;
44
45 /* hash table crap */
46 struct dsthash_dst {
47 union {
48 struct {
49 __be32 src;
50 __be32 dst;
51 } ip;
52 #if defined(CONFIG_IP6_NF_IPTABLES) || defined(CONFIG_IP6_NF_IPTABLES_MODULE)
53 struct {
54 __be32 src[4];
55 __be32 dst[4];
56 } ip6;
57 #endif
58 } addr;
59 __be16 src_port;
60 __be16 dst_port;
61 };
62
63 struct dsthash_ent {
64 /* static / read-only parts in the beginning */
65 struct hlist_node node;
66 struct dsthash_dst dst;
67
68 /* modified structure members in the end */
69 unsigned long expires; /* precalculated expiry time */
70 struct {
71 unsigned long prev; /* last modification */
72 u_int32_t credit;
73 u_int32_t credit_cap, cost;
74 } rateinfo;
75 };
76
77 struct xt_hashlimit_htable {
78 struct hlist_node node; /* global list of all htables */
79 int use;
80 int family;
81
82 struct hashlimit_cfg cfg; /* config */
83
84 /* used internally */
85 spinlock_t lock; /* lock for list_head */
86 u_int32_t rnd; /* random seed for hash */
87 int rnd_initialized;
88 unsigned int count; /* number entries in table */
89 struct timer_list timer; /* timer for gc */
90
91 /* seq_file stuff */
92 struct proc_dir_entry *pde;
93
94 struct hlist_head hash[0]; /* hashtable itself */
95 };
96
97 static DEFINE_MUTEX(hashlimit_mutex); /* protects htables list */
98 static HLIST_HEAD(hashlimit_htables);
99 static struct kmem_cache *hashlimit_cachep __read_mostly;
100
101 static inline int dst_cmp(const struct dsthash_ent *ent, struct dsthash_dst *b)
102 {
103 return !memcmp(&ent->dst, b, sizeof(ent->dst));
104 }
105
106 static u_int32_t
107 hash_dst(const struct xt_hashlimit_htable *ht, const struct dsthash_dst *dst)
108 {
109 u_int32_t hash = jhash2((const u32 *)dst,
110 sizeof(*dst)/sizeof(u32),
111 ht->rnd);
112 /*
113 * Instead of returning hash % ht->cfg.size (implying a divide)
114 * we return the high 32 bits of the (hash * ht->cfg.size) that will
115 * give results between [0 and cfg.size-1] and same hash distribution,
116 * but using a multiply, less expensive than a divide
117 */
118 return ((u64)hash * ht->cfg.size) >> 32;
119 }
120
121 static struct dsthash_ent *
122 dsthash_find(const struct xt_hashlimit_htable *ht, struct dsthash_dst *dst)
123 {
124 struct dsthash_ent *ent;
125 struct hlist_node *pos;
126 u_int32_t hash = hash_dst(ht, dst);
127
128 if (!hlist_empty(&ht->hash[hash])) {
129 hlist_for_each_entry(ent, pos, &ht->hash[hash], node)
130 if (dst_cmp(ent, dst))
131 return ent;
132 }
133 return NULL;
134 }
135
136 /* allocate dsthash_ent, initialize dst, put in htable and lock it */
137 static struct dsthash_ent *
138 dsthash_alloc_init(struct xt_hashlimit_htable *ht, struct dsthash_dst *dst)
139 {
140 struct dsthash_ent *ent;
141
142 /* initialize hash with random val at the time we allocate
143 * the first hashtable entry */
144 if (!ht->rnd_initialized) {
145 get_random_bytes(&ht->rnd, 4);
146 ht->rnd_initialized = 1;
147 }
148
149 if (ht->cfg.max && ht->count >= ht->cfg.max) {
150 /* FIXME: do something. question is what.. */
151 if (net_ratelimit())
152 printk(KERN_WARNING
153 "xt_hashlimit: max count of %u reached\n",
154 ht->cfg.max);
155 return NULL;
156 }
157
158 ent = kmem_cache_alloc(hashlimit_cachep, GFP_ATOMIC);
159 if (!ent) {
160 if (net_ratelimit())
161 printk(KERN_ERR
162 "xt_hashlimit: can't allocate dsthash_ent\n");
163 return NULL;
164 }
165 memcpy(&ent->dst, dst, sizeof(ent->dst));
166
167 hlist_add_head(&ent->node, &ht->hash[hash_dst(ht, dst)]);
168 ht->count++;
169 return ent;
170 }
171
172 static inline void
173 dsthash_free(struct xt_hashlimit_htable *ht, struct dsthash_ent *ent)
174 {
175 hlist_del(&ent->node);
176 kmem_cache_free(hashlimit_cachep, ent);
177 ht->count--;
178 }
179 static void htable_gc(unsigned long htlong);
180
181 static int htable_create(struct xt_hashlimit_info *minfo, int family)
182 {
183 struct xt_hashlimit_htable *hinfo;
184 unsigned int size;
185 unsigned int i;
186
187 if (minfo->cfg.size)
188 size = minfo->cfg.size;
189 else {
190 size = ((num_physpages << PAGE_SHIFT) / 16384) /
191 sizeof(struct list_head);
192 if (num_physpages > (1024 * 1024 * 1024 / PAGE_SIZE))
193 size = 8192;
194 if (size < 16)
195 size = 16;
196 }
197 /* FIXME: don't use vmalloc() here or anywhere else -HW */
198 hinfo = vmalloc(sizeof(struct xt_hashlimit_htable) +
199 sizeof(struct list_head) * size);
200 if (!hinfo) {
201 printk(KERN_ERR "xt_hashlimit: unable to create hashtable\n");
202 return -1;
203 }
204 minfo->hinfo = hinfo;
205
206 /* copy match config into hashtable config */
207 memcpy(&hinfo->cfg, &minfo->cfg, sizeof(hinfo->cfg));
208 hinfo->cfg.size = size;
209 if (!hinfo->cfg.max)
210 hinfo->cfg.max = 8 * hinfo->cfg.size;
211 else if (hinfo->cfg.max < hinfo->cfg.size)
212 hinfo->cfg.max = hinfo->cfg.size;
213
214 for (i = 0; i < hinfo->cfg.size; i++)
215 INIT_HLIST_HEAD(&hinfo->hash[i]);
216
217 hinfo->use = 1;
218 hinfo->count = 0;
219 hinfo->family = family;
220 hinfo->rnd_initialized = 0;
221 spin_lock_init(&hinfo->lock);
222 hinfo->pde = create_proc_entry(minfo->name, 0,
223 family == AF_INET ? hashlimit_procdir4 :
224 hashlimit_procdir6);
225 if (!hinfo->pde) {
226 vfree(hinfo);
227 return -1;
228 }
229 hinfo->pde->proc_fops = &dl_file_ops;
230 hinfo->pde->data = hinfo;
231
232 setup_timer(&hinfo->timer, htable_gc, (unsigned long )hinfo);
233 hinfo->timer.expires = jiffies + msecs_to_jiffies(hinfo->cfg.gc_interval);
234 add_timer(&hinfo->timer);
235
236 hlist_add_head(&hinfo->node, &hashlimit_htables);
237
238 return 0;
239 }
240
241 static int select_all(struct xt_hashlimit_htable *ht, struct dsthash_ent *he)
242 {
243 return 1;
244 }
245
246 static int select_gc(struct xt_hashlimit_htable *ht, struct dsthash_ent *he)
247 {
248 return time_after_eq(jiffies, he->expires);
249 }
250
251 static void htable_selective_cleanup(struct xt_hashlimit_htable *ht,
252 int (*select)(struct xt_hashlimit_htable *ht,
253 struct dsthash_ent *he))
254 {
255 unsigned int i;
256
257 /* lock hash table and iterate over it */
258 spin_lock_bh(&ht->lock);
259 for (i = 0; i < ht->cfg.size; i++) {
260 struct dsthash_ent *dh;
261 struct hlist_node *pos, *n;
262 hlist_for_each_entry_safe(dh, pos, n, &ht->hash[i], node) {
263 if ((*select)(ht, dh))
264 dsthash_free(ht, dh);
265 }
266 }
267 spin_unlock_bh(&ht->lock);
268 }
269
270 /* hash table garbage collector, run by timer */
271 static void htable_gc(unsigned long htlong)
272 {
273 struct xt_hashlimit_htable *ht = (struct xt_hashlimit_htable *)htlong;
274
275 htable_selective_cleanup(ht, select_gc);
276
277 /* re-add the timer accordingly */
278 ht->timer.expires = jiffies + msecs_to_jiffies(ht->cfg.gc_interval);
279 add_timer(&ht->timer);
280 }
281
282 static void htable_destroy(struct xt_hashlimit_htable *hinfo)
283 {
284 del_timer_sync(&hinfo->timer);
285
286 /* remove proc entry */
287 remove_proc_entry(hinfo->pde->name,
288 hinfo->family == AF_INET ? hashlimit_procdir4 :
289 hashlimit_procdir6);
290 htable_selective_cleanup(hinfo, select_all);
291 vfree(hinfo);
292 }
293
294 static struct xt_hashlimit_htable *htable_find_get(char *name, int family)
295 {
296 struct xt_hashlimit_htable *hinfo;
297 struct hlist_node *pos;
298
299 hlist_for_each_entry(hinfo, pos, &hashlimit_htables, node) {
300 if (!strcmp(name, hinfo->pde->name) &&
301 hinfo->family == family) {
302 hinfo->use++;
303 return hinfo;
304 }
305 }
306 return NULL;
307 }
308
309 static void htable_put(struct xt_hashlimit_htable *hinfo)
310 {
311 mutex_lock(&hashlimit_mutex);
312 if (--hinfo->use == 0) {
313 hlist_del(&hinfo->node);
314 htable_destroy(hinfo);
315 }
316 mutex_unlock(&hashlimit_mutex);
317 }
318
319 /* The algorithm used is the Simple Token Bucket Filter (TBF)
320 * see net/sched/sch_tbf.c in the linux source tree
321 */
322
323 /* Rusty: This is my (non-mathematically-inclined) understanding of
324 this algorithm. The `average rate' in jiffies becomes your initial
325 amount of credit `credit' and the most credit you can ever have
326 `credit_cap'. The `peak rate' becomes the cost of passing the
327 test, `cost'.
328
329 `prev' tracks the last packet hit: you gain one credit per jiffy.
330 If you get credit balance more than this, the extra credit is
331 discarded. Every time the match passes, you lose `cost' credits;
332 if you don't have that many, the test fails.
333
334 See Alexey's formal explanation in net/sched/sch_tbf.c.
335
336 To get the maximum range, we multiply by this factor (ie. you get N
337 credits per jiffy). We want to allow a rate as low as 1 per day
338 (slowest userspace tool allows), which means
339 CREDITS_PER_JIFFY*HZ*60*60*24 < 2^32 ie.
340 */
341 #define MAX_CPJ (0xFFFFFFFF / (HZ*60*60*24))
342
343 /* Repeated shift and or gives us all 1s, final shift and add 1 gives
344 * us the power of 2 below the theoretical max, so GCC simply does a
345 * shift. */
346 #define _POW2_BELOW2(x) ((x)|((x)>>1))
347 #define _POW2_BELOW4(x) (_POW2_BELOW2(x)|_POW2_BELOW2((x)>>2))
348 #define _POW2_BELOW8(x) (_POW2_BELOW4(x)|_POW2_BELOW4((x)>>4))
349 #define _POW2_BELOW16(x) (_POW2_BELOW8(x)|_POW2_BELOW8((x)>>8))
350 #define _POW2_BELOW32(x) (_POW2_BELOW16(x)|_POW2_BELOW16((x)>>16))
351 #define POW2_BELOW32(x) ((_POW2_BELOW32(x)>>1) + 1)
352
353 #define CREDITS_PER_JIFFY POW2_BELOW32(MAX_CPJ)
354
355 /* Precision saver. */
356 static inline u_int32_t
357 user2credits(u_int32_t user)
358 {
359 /* If multiplying would overflow... */
360 if (user > 0xFFFFFFFF / (HZ*CREDITS_PER_JIFFY))
361 /* Divide first. */
362 return (user / XT_HASHLIMIT_SCALE) * HZ * CREDITS_PER_JIFFY;
363
364 return (user * HZ * CREDITS_PER_JIFFY) / XT_HASHLIMIT_SCALE;
365 }
366
367 static inline void rateinfo_recalc(struct dsthash_ent *dh, unsigned long now)
368 {
369 dh->rateinfo.credit += (now - dh->rateinfo.prev) * CREDITS_PER_JIFFY;
370 if (dh->rateinfo.credit > dh->rateinfo.credit_cap)
371 dh->rateinfo.credit = dh->rateinfo.credit_cap;
372 dh->rateinfo.prev = now;
373 }
374
375 static int
376 hashlimit_init_dst(struct xt_hashlimit_htable *hinfo, struct dsthash_dst *dst,
377 const struct sk_buff *skb, unsigned int protoff)
378 {
379 __be16 _ports[2], *ports;
380 u8 nexthdr;
381
382 memset(dst, 0, sizeof(*dst));
383
384 switch (hinfo->family) {
385 case AF_INET:
386 if (hinfo->cfg.mode & XT_HASHLIMIT_HASH_DIP)
387 dst->addr.ip.dst = ip_hdr(skb)->daddr;
388 if (hinfo->cfg.mode & XT_HASHLIMIT_HASH_SIP)
389 dst->addr.ip.src = ip_hdr(skb)->saddr;
390
391 if (!(hinfo->cfg.mode &
392 (XT_HASHLIMIT_HASH_DPT | XT_HASHLIMIT_HASH_SPT)))
393 return 0;
394 nexthdr = ip_hdr(skb)->protocol;
395 break;
396 #if defined(CONFIG_IP6_NF_IPTABLES) || defined(CONFIG_IP6_NF_IPTABLES_MODULE)
397 case AF_INET6:
398 if (hinfo->cfg.mode & XT_HASHLIMIT_HASH_DIP)
399 memcpy(&dst->addr.ip6.dst, &ipv6_hdr(skb)->daddr,
400 sizeof(dst->addr.ip6.dst));
401 if (hinfo->cfg.mode & XT_HASHLIMIT_HASH_SIP)
402 memcpy(&dst->addr.ip6.src, &ipv6_hdr(skb)->saddr,
403 sizeof(dst->addr.ip6.src));
404
405 if (!(hinfo->cfg.mode &
406 (XT_HASHLIMIT_HASH_DPT | XT_HASHLIMIT_HASH_SPT)))
407 return 0;
408 nexthdr = ipv6_hdr(skb)->nexthdr;
409 protoff = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), &nexthdr);
410 if ((int)protoff < 0)
411 return -1;
412 break;
413 #endif
414 default:
415 BUG();
416 return 0;
417 }
418
419 switch (nexthdr) {
420 case IPPROTO_TCP:
421 case IPPROTO_UDP:
422 case IPPROTO_UDPLITE:
423 case IPPROTO_SCTP:
424 case IPPROTO_DCCP:
425 ports = skb_header_pointer(skb, protoff, sizeof(_ports),
426 &_ports);
427 break;
428 default:
429 _ports[0] = _ports[1] = 0;
430 ports = _ports;
431 break;
432 }
433 if (!ports)
434 return -1;
435 if (hinfo->cfg.mode & XT_HASHLIMIT_HASH_SPT)
436 dst->src_port = ports[0];
437 if (hinfo->cfg.mode & XT_HASHLIMIT_HASH_DPT)
438 dst->dst_port = ports[1];
439 return 0;
440 }
441
442 static int
443 hashlimit_match(const struct sk_buff *skb,
444 const struct net_device *in,
445 const struct net_device *out,
446 const struct xt_match *match,
447 const void *matchinfo,
448 int offset,
449 unsigned int protoff,
450 int *hotdrop)
451 {
452 const struct xt_hashlimit_info *r = matchinfo;
453
454 struct xt_hashlimit_htable *hinfo = r->hinfo;
455 unsigned long now = jiffies;
456 struct dsthash_ent *dh;
457 struct dsthash_dst dst;
458
459 if (hashlimit_init_dst(hinfo, &dst, skb, protoff) < 0)
460 goto hotdrop;
461
462 spin_lock_bh(&hinfo->lock);
463 dh = dsthash_find(hinfo, &dst);
464 if (!dh) {
465 dh = dsthash_alloc_init(hinfo, &dst);
466 if (!dh) {
467 spin_unlock_bh(&hinfo->lock);
468 goto hotdrop;
469 }
470
471 dh->expires = jiffies + msecs_to_jiffies(hinfo->cfg.expire);
472 dh->rateinfo.prev = jiffies;
473 dh->rateinfo.credit = user2credits(hinfo->cfg.avg *
474 hinfo->cfg.burst);
475 dh->rateinfo.credit_cap = user2credits(hinfo->cfg.avg *
476 hinfo->cfg.burst);
477 dh->rateinfo.cost = user2credits(hinfo->cfg.avg);
478 } else {
479 /* update expiration timeout */
480 dh->expires = now + msecs_to_jiffies(hinfo->cfg.expire);
481 rateinfo_recalc(dh, now);
482 }
483
484 if (dh->rateinfo.credit >= dh->rateinfo.cost) {
485 /* We're underlimit. */
486 dh->rateinfo.credit -= dh->rateinfo.cost;
487 spin_unlock_bh(&hinfo->lock);
488 return 1;
489 }
490
491 spin_unlock_bh(&hinfo->lock);
492
493 /* default case: we're overlimit, thus don't match */
494 return 0;
495
496 hotdrop:
497 *hotdrop = 1;
498 return 0;
499 }
500
501 static int
502 hashlimit_checkentry(const char *tablename,
503 const void *inf,
504 const struct xt_match *match,
505 void *matchinfo,
506 unsigned int hook_mask)
507 {
508 struct xt_hashlimit_info *r = matchinfo;
509
510 /* Check for overflow. */
511 if (r->cfg.burst == 0 ||
512 user2credits(r->cfg.avg * r->cfg.burst) < user2credits(r->cfg.avg)) {
513 printk(KERN_ERR "xt_hashlimit: overflow, try lower: %u/%u\n",
514 r->cfg.avg, r->cfg.burst);
515 return 0;
516 }
517 if (r->cfg.mode == 0 ||
518 r->cfg.mode > (XT_HASHLIMIT_HASH_DPT |
519 XT_HASHLIMIT_HASH_DIP |
520 XT_HASHLIMIT_HASH_SIP |
521 XT_HASHLIMIT_HASH_SPT))
522 return 0;
523 if (!r->cfg.gc_interval)
524 return 0;
525 if (!r->cfg.expire)
526 return 0;
527 if (r->name[sizeof(r->name) - 1] != '\0')
528 return 0;
529
530 mutex_lock(&hashlimit_mutex);
531 r->hinfo = htable_find_get(r->name, match->family);
532 if (!r->hinfo && htable_create(r, match->family) != 0) {
533 mutex_unlock(&hashlimit_mutex);
534 return 0;
535 }
536 mutex_unlock(&hashlimit_mutex);
537
538 return 1;
539 }
540
541 static void
542 hashlimit_destroy(const struct xt_match *match, void *matchinfo)
543 {
544 struct xt_hashlimit_info *r = matchinfo;
545
546 htable_put(r->hinfo);
547 }
548
549 #ifdef CONFIG_COMPAT
550 struct compat_xt_hashlimit_info {
551 char name[IFNAMSIZ];
552 struct hashlimit_cfg cfg;
553 compat_uptr_t hinfo;
554 compat_uptr_t master;
555 };
556
557 static void compat_from_user(void *dst, void *src)
558 {
559 int off = offsetof(struct compat_xt_hashlimit_info, hinfo);
560
561 memcpy(dst, src, off);
562 memset(dst + off, 0, sizeof(struct compat_xt_hashlimit_info) - off);
563 }
564
565 static int compat_to_user(void __user *dst, void *src)
566 {
567 int off = offsetof(struct compat_xt_hashlimit_info, hinfo);
568
569 return copy_to_user(dst, src, off) ? -EFAULT : 0;
570 }
571 #endif
572
573 static struct xt_match xt_hashlimit[] = {
574 {
575 .name = "hashlimit",
576 .family = AF_INET,
577 .match = hashlimit_match,
578 .matchsize = sizeof(struct xt_hashlimit_info),
579 #ifdef CONFIG_COMPAT
580 .compatsize = sizeof(struct compat_xt_hashlimit_info),
581 .compat_from_user = compat_from_user,
582 .compat_to_user = compat_to_user,
583 #endif
584 .checkentry = hashlimit_checkentry,
585 .destroy = hashlimit_destroy,
586 .me = THIS_MODULE
587 },
588 #if defined(CONFIG_IP6_NF_IPTABLES) || defined(CONFIG_IP6_NF_IPTABLES_MODULE)
589 {
590 .name = "hashlimit",
591 .family = AF_INET6,
592 .match = hashlimit_match,
593 .matchsize = sizeof(struct xt_hashlimit_info),
594 #ifdef CONFIG_COMPAT
595 .compatsize = sizeof(struct compat_xt_hashlimit_info),
596 .compat_from_user = compat_from_user,
597 .compat_to_user = compat_to_user,
598 #endif
599 .checkentry = hashlimit_checkentry,
600 .destroy = hashlimit_destroy,
601 .me = THIS_MODULE
602 },
603 #endif
604 };
605
606 /* PROC stuff */
607 static void *dl_seq_start(struct seq_file *s, loff_t *pos)
608 {
609 struct proc_dir_entry *pde = s->private;
610 struct xt_hashlimit_htable *htable = pde->data;
611 unsigned int *bucket;
612
613 spin_lock_bh(&htable->lock);
614 if (*pos >= htable->cfg.size)
615 return NULL;
616
617 bucket = kmalloc(sizeof(unsigned int), GFP_ATOMIC);
618 if (!bucket)
619 return ERR_PTR(-ENOMEM);
620
621 *bucket = *pos;
622 return bucket;
623 }
624
625 static void *dl_seq_next(struct seq_file *s, void *v, loff_t *pos)
626 {
627 struct proc_dir_entry *pde = s->private;
628 struct xt_hashlimit_htable *htable = pde->data;
629 unsigned int *bucket = (unsigned int *)v;
630
631 *pos = ++(*bucket);
632 if (*pos >= htable->cfg.size) {
633 kfree(v);
634 return NULL;
635 }
636 return bucket;
637 }
638
639 static void dl_seq_stop(struct seq_file *s, void *v)
640 {
641 struct proc_dir_entry *pde = s->private;
642 struct xt_hashlimit_htable *htable = pde->data;
643 unsigned int *bucket = (unsigned int *)v;
644
645 if (!IS_ERR(bucket))
646 kfree(bucket);
647 spin_unlock_bh(&htable->lock);
648 }
649
650 static int dl_seq_real_show(struct dsthash_ent *ent, int family,
651 struct seq_file *s)
652 {
653 /* recalculate to show accurate numbers */
654 rateinfo_recalc(ent, jiffies);
655
656 switch (family) {
657 case AF_INET:
658 return seq_printf(s, "%ld %u.%u.%u.%u:%u->"
659 "%u.%u.%u.%u:%u %u %u %u\n",
660 (long)(ent->expires - jiffies)/HZ,
661 NIPQUAD(ent->dst.addr.ip.src),
662 ntohs(ent->dst.src_port),
663 NIPQUAD(ent->dst.addr.ip.dst),
664 ntohs(ent->dst.dst_port),
665 ent->rateinfo.credit, ent->rateinfo.credit_cap,
666 ent->rateinfo.cost);
667 #if defined(CONFIG_IP6_NF_IPTABLES) || defined(CONFIG_IP6_NF_IPTABLES_MODULE)
668 case AF_INET6:
669 return seq_printf(s, "%ld " NIP6_FMT ":%u->"
670 NIP6_FMT ":%u %u %u %u\n",
671 (long)(ent->expires - jiffies)/HZ,
672 NIP6(*(struct in6_addr *)&ent->dst.addr.ip6.src),
673 ntohs(ent->dst.src_port),
674 NIP6(*(struct in6_addr *)&ent->dst.addr.ip6.dst),
675 ntohs(ent->dst.dst_port),
676 ent->rateinfo.credit, ent->rateinfo.credit_cap,
677 ent->rateinfo.cost);
678 #endif
679 default:
680 BUG();
681 return 0;
682 }
683 }
684
685 static int dl_seq_show(struct seq_file *s, void *v)
686 {
687 struct proc_dir_entry *pde = s->private;
688 struct xt_hashlimit_htable *htable = pde->data;
689 unsigned int *bucket = (unsigned int *)v;
690 struct dsthash_ent *ent;
691 struct hlist_node *pos;
692
693 if (!hlist_empty(&htable->hash[*bucket])) {
694 hlist_for_each_entry(ent, pos, &htable->hash[*bucket], node)
695 if (dl_seq_real_show(ent, htable->family, s))
696 return -1;
697 }
698 return 0;
699 }
700
701 static struct seq_operations dl_seq_ops = {
702 .start = dl_seq_start,
703 .next = dl_seq_next,
704 .stop = dl_seq_stop,
705 .show = dl_seq_show
706 };
707
708 static int dl_proc_open(struct inode *inode, struct file *file)
709 {
710 int ret = seq_open(file, &dl_seq_ops);
711
712 if (!ret) {
713 struct seq_file *sf = file->private_data;
714 sf->private = PDE(inode);
715 }
716 return ret;
717 }
718
719 static const struct file_operations dl_file_ops = {
720 .owner = THIS_MODULE,
721 .open = dl_proc_open,
722 .read = seq_read,
723 .llseek = seq_lseek,
724 .release = seq_release
725 };
726
727 static int __init xt_hashlimit_init(void)
728 {
729 int err;
730
731 err = xt_register_matches(xt_hashlimit, ARRAY_SIZE(xt_hashlimit));
732 if (err < 0)
733 goto err1;
734
735 err = -ENOMEM;
736 hashlimit_cachep = kmem_cache_create("xt_hashlimit",
737 sizeof(struct dsthash_ent), 0, 0,
738 NULL, NULL);
739 if (!hashlimit_cachep) {
740 printk(KERN_ERR "xt_hashlimit: unable to create slab cache\n");
741 goto err2;
742 }
743 hashlimit_procdir4 = proc_mkdir("ipt_hashlimit", proc_net);
744 if (!hashlimit_procdir4) {
745 printk(KERN_ERR "xt_hashlimit: unable to create proc dir "
746 "entry\n");
747 goto err3;
748 }
749 err = 0;
750 #if defined(CONFIG_IP6_NF_IPTABLES) || defined(CONFIG_IP6_NF_IPTABLES_MODULE)
751 hashlimit_procdir6 = proc_mkdir("ip6t_hashlimit", proc_net);
752 if (!hashlimit_procdir6) {
753 printk(KERN_ERR "xt_hashlimit: unable to create proc dir "
754 "entry\n");
755 err = -ENOMEM;
756 }
757 #endif
758 if (!err)
759 return 0;
760 remove_proc_entry("ipt_hashlimit", proc_net);
761 err3:
762 kmem_cache_destroy(hashlimit_cachep);
763 err2:
764 xt_unregister_matches(xt_hashlimit, ARRAY_SIZE(xt_hashlimit));
765 err1:
766 return err;
767
768 }
769
770 static void __exit xt_hashlimit_fini(void)
771 {
772 remove_proc_entry("ipt_hashlimit", proc_net);
773 #if defined(CONFIG_IP6_NF_IPTABLES) || defined(CONFIG_IP6_NF_IPTABLES_MODULE)
774 remove_proc_entry("ip6t_hashlimit", proc_net);
775 #endif
776 kmem_cache_destroy(hashlimit_cachep);
777 xt_unregister_matches(xt_hashlimit, ARRAY_SIZE(xt_hashlimit));
778 }
779
780 module_init(xt_hashlimit_init);
781 module_exit(xt_hashlimit_fini);
Tomato firmware and modifications.