2 * xt_hashlimit - Netfilter module to limit the number of packets per time
3 * separately for each hashbucket (sourceip/sourceport/dstip/dstport)
5 * (C) 2003-2004 by Harald Welte <laforge@netfilter.org>
6 * Copyright © CC Computer Consultants GmbH, 2007 - 2008
8 * Development of this code was funded by Astaro AG, http://www.astaro.com/
10 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
11 #include <linux/module.h>
12 #include <linux/spinlock.h>
13 #include <linux/random.h>
14 #include <linux/jhash.h>
15 #include <linux/slab.h>
16 #include <linux/vmalloc.h>
17 #include <linux/proc_fs.h>
18 #include <linux/seq_file.h>
19 #include <linux/list.h>
20 #include <linux/skbuff.h>
24 #if IS_ENABLED(CONFIG_IP6_NF_IPTABLES)
25 #include <linux/ipv6.h>
29 #include <net/net_namespace.h>
30 #include <net/netns/generic.h>
32 #include <linux/netfilter/x_tables.h>
33 #include <linux/netfilter_ipv4/ip_tables.h>
34 #include <linux/netfilter_ipv6/ip6_tables.h>
35 #include <linux/netfilter/xt_hashlimit.h>
36 #include <linux/mutex.h>
38 MODULE_LICENSE("GPL");
39 MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");
40 MODULE_AUTHOR("Jan Engelhardt <jengelh@medozas.de>");
41 MODULE_DESCRIPTION("Xtables: per hash-bucket rate-limit match");
42 MODULE_ALIAS("ipt_hashlimit");
43 MODULE_ALIAS("ip6t_hashlimit");
45 struct hashlimit_net
{
46 struct hlist_head htables
;
47 struct proc_dir_entry
*ipt_hashlimit
;
48 struct proc_dir_entry
*ip6t_hashlimit
;
51 static int hashlimit_net_id
;
52 static inline struct hashlimit_net
*hashlimit_pernet(struct net
*net
)
54 return net_generic(net
, hashlimit_net_id
);
57 /* need to declare this at the top */
58 static const struct file_operations dl_file_ops
;
67 #if IS_ENABLED(CONFIG_IP6_NF_IPTABLES)
79 /* static / read-only parts in the beginning */
80 struct hlist_node node
;
81 struct dsthash_dst dst
;
83 /* modified structure members in the end */
85 unsigned long expires
; /* precalculated expiry time */
87 unsigned long prev
; /* last modification */
89 u_int32_t credit_cap
, cost
;
94 struct xt_hashlimit_htable
{
95 struct hlist_node node
; /* global list of all htables */
100 struct hashlimit_cfg1 cfg
; /* config */
102 /* used internally */
103 spinlock_t lock
; /* lock for list_head */
104 u_int32_t rnd
; /* random seed for hash */
105 unsigned int count
; /* number entries in table */
106 struct timer_list timer
; /* timer for gc */
109 struct proc_dir_entry
*pde
;
112 struct hlist_head hash
[0]; /* hashtable itself */
115 static DEFINE_MUTEX(hashlimit_mutex
); /* protects htables list */
116 static struct kmem_cache
*hashlimit_cachep __read_mostly
;
118 static inline bool dst_cmp(const struct dsthash_ent
*ent
,
119 const struct dsthash_dst
*b
)
121 return !memcmp(&ent
->dst
, b
, sizeof(ent
->dst
));
125 hash_dst(const struct xt_hashlimit_htable
*ht
, const struct dsthash_dst
*dst
)
127 u_int32_t hash
= jhash2((const u32
*)dst
,
128 sizeof(*dst
)/sizeof(u32
),
131 * Instead of returning hash % ht->cfg.size (implying a divide)
132 * we return the high 32 bits of the (hash * ht->cfg.size) that will
133 * give results between [0 and cfg.size-1] and same hash distribution,
134 * but using a multiply, less expensive than a divide
136 return ((u64
)hash
* ht
->cfg
.size
) >> 32;
139 static struct dsthash_ent
*
140 dsthash_find(const struct xt_hashlimit_htable
*ht
,
141 const struct dsthash_dst
*dst
)
143 struct dsthash_ent
*ent
;
144 struct hlist_node
*pos
;
145 u_int32_t hash
= hash_dst(ht
, dst
);
147 if (!hlist_empty(&ht
->hash
[hash
])) {
148 hlist_for_each_entry_rcu(ent
, pos
, &ht
->hash
[hash
], node
)
149 if (dst_cmp(ent
, dst
)) {
150 spin_lock(&ent
->lock
);
157 /* allocate dsthash_ent, initialize dst, put in htable and lock it */
158 static struct dsthash_ent
*
159 dsthash_alloc_init(struct xt_hashlimit_htable
*ht
,
160 const struct dsthash_dst
*dst
)
162 struct dsthash_ent
*ent
;
164 spin_lock(&ht
->lock
);
165 /* initialize hash with random val at the time we allocate
166 * the first hashtable entry */
167 if (unlikely(!ht
->rnd_initialized
)) {
168 get_random_bytes(&ht
->rnd
, sizeof(ht
->rnd
));
169 ht
->rnd_initialized
= true;
172 if (ht
->cfg
.max
&& ht
->count
>= ht
->cfg
.max
) {
173 /* FIXME: do something. question is what.. */
175 pr_err("max count of %u reached\n", ht
->cfg
.max
);
178 ent
= kmem_cache_alloc(hashlimit_cachep
, GFP_ATOMIC
);
180 memcpy(&ent
->dst
, dst
, sizeof(ent
->dst
));
181 spin_lock_init(&ent
->lock
);
183 spin_lock(&ent
->lock
);
184 hlist_add_head_rcu(&ent
->node
, &ht
->hash
[hash_dst(ht
, dst
)]);
187 spin_unlock(&ht
->lock
);
191 static void dsthash_free_rcu(struct rcu_head
*head
)
193 struct dsthash_ent
*ent
= container_of(head
, struct dsthash_ent
, rcu
);
195 kmem_cache_free(hashlimit_cachep
, ent
);
199 dsthash_free(struct xt_hashlimit_htable
*ht
, struct dsthash_ent
*ent
)
201 hlist_del_rcu(&ent
->node
);
202 call_rcu_bh(&ent
->rcu
, dsthash_free_rcu
);
205 static void htable_gc(unsigned long htlong
);
207 static int htable_create(struct net
*net
, struct xt_hashlimit_mtinfo1
*minfo
,
210 struct hashlimit_net
*hashlimit_net
= hashlimit_pernet(net
);
211 struct xt_hashlimit_htable
*hinfo
;
215 if (minfo
->cfg
.size
) {
216 size
= minfo
->cfg
.size
;
218 size
= (totalram_pages
<< PAGE_SHIFT
) / 16384 /
219 sizeof(struct list_head
);
220 if (totalram_pages
> 1024 * 1024 * 1024 / PAGE_SIZE
)
225 /* FIXME: don't use vmalloc() here or anywhere else -HW */
226 hinfo
= vmalloc(sizeof(struct xt_hashlimit_htable
) +
227 sizeof(struct list_head
) * size
);
230 minfo
->hinfo
= hinfo
;
232 /* copy match config into hashtable config */
233 memcpy(&hinfo
->cfg
, &minfo
->cfg
, sizeof(hinfo
->cfg
));
234 hinfo
->cfg
.size
= size
;
235 if (hinfo
->cfg
.max
== 0)
236 hinfo
->cfg
.max
= 8 * hinfo
->cfg
.size
;
237 else if (hinfo
->cfg
.max
< hinfo
->cfg
.size
)
238 hinfo
->cfg
.max
= hinfo
->cfg
.size
;
240 for (i
= 0; i
< hinfo
->cfg
.size
; i
++)
241 INIT_HLIST_HEAD(&hinfo
->hash
[i
]);
245 hinfo
->family
= family
;
246 hinfo
->rnd_initialized
= false;
247 spin_lock_init(&hinfo
->lock
);
249 hinfo
->pde
= proc_create_data(minfo
->name
, 0,
250 (family
== NFPROTO_IPV4
) ?
251 hashlimit_net
->ipt_hashlimit
: hashlimit_net
->ip6t_hashlimit
,
252 &dl_file_ops
, hinfo
);
253 if (hinfo
->pde
== NULL
) {
259 setup_timer(&hinfo
->timer
, htable_gc
, (unsigned long)hinfo
);
260 hinfo
->timer
.expires
= jiffies
+ msecs_to_jiffies(hinfo
->cfg
.gc_interval
);
261 add_timer(&hinfo
->timer
);
263 hlist_add_head(&hinfo
->node
, &hashlimit_net
->htables
);
268 static bool select_all(const struct xt_hashlimit_htable
*ht
,
269 const struct dsthash_ent
*he
)
274 static bool select_gc(const struct xt_hashlimit_htable
*ht
,
275 const struct dsthash_ent
*he
)
277 return time_after_eq(jiffies
, he
->expires
);
280 static void htable_selective_cleanup(struct xt_hashlimit_htable
*ht
,
281 bool (*select
)(const struct xt_hashlimit_htable
*ht
,
282 const struct dsthash_ent
*he
))
286 /* lock hash table and iterate over it */
287 spin_lock_bh(&ht
->lock
);
288 for (i
= 0; i
< ht
->cfg
.size
; i
++) {
289 struct dsthash_ent
*dh
;
290 struct hlist_node
*pos
, *n
;
291 hlist_for_each_entry_safe(dh
, pos
, n
, &ht
->hash
[i
], node
) {
292 if ((*select
)(ht
, dh
))
293 dsthash_free(ht
, dh
);
296 spin_unlock_bh(&ht
->lock
);
299 /* hash table garbage collector, run by timer */
300 static void htable_gc(unsigned long htlong
)
302 struct xt_hashlimit_htable
*ht
= (struct xt_hashlimit_htable
*)htlong
;
304 htable_selective_cleanup(ht
, select_gc
);
306 /* re-add the timer accordingly */
307 ht
->timer
.expires
= jiffies
+ msecs_to_jiffies(ht
->cfg
.gc_interval
);
308 add_timer(&ht
->timer
);
311 static void htable_destroy(struct xt_hashlimit_htable
*hinfo
)
313 struct hashlimit_net
*hashlimit_net
= hashlimit_pernet(hinfo
->net
);
314 struct proc_dir_entry
*parent
;
316 del_timer_sync(&hinfo
->timer
);
318 if (hinfo
->family
== NFPROTO_IPV4
)
319 parent
= hashlimit_net
->ipt_hashlimit
;
321 parent
= hashlimit_net
->ip6t_hashlimit
;
322 remove_proc_entry(hinfo
->pde
->name
, parent
);
323 htable_selective_cleanup(hinfo
, select_all
);
327 static struct xt_hashlimit_htable
*htable_find_get(struct net
*net
,
331 struct hashlimit_net
*hashlimit_net
= hashlimit_pernet(net
);
332 struct xt_hashlimit_htable
*hinfo
;
333 struct hlist_node
*pos
;
335 hlist_for_each_entry(hinfo
, pos
, &hashlimit_net
->htables
, node
) {
336 if (!strcmp(name
, hinfo
->pde
->name
) &&
337 hinfo
->family
== family
) {
345 static void htable_put(struct xt_hashlimit_htable
*hinfo
)
347 mutex_lock(&hashlimit_mutex
);
348 if (--hinfo
->use
== 0) {
349 hlist_del(&hinfo
->node
);
350 htable_destroy(hinfo
);
352 mutex_unlock(&hashlimit_mutex
);
355 /* The algorithm used is the Simple Token Bucket Filter (TBF)
356 * see net/sched/sch_tbf.c in the linux source tree
359 /* Rusty: This is my (non-mathematically-inclined) understanding of
360 this algorithm. The `average rate' in jiffies becomes your initial
361 amount of credit `credit' and the most credit you can ever have
362 `credit_cap'. The `peak rate' becomes the cost of passing the
365 `prev' tracks the last packet hit: you gain one credit per jiffy.
366 If you get credit balance more than this, the extra credit is
367 discarded. Every time the match passes, you lose `cost' credits;
368 if you don't have that many, the test fails.
370 See Alexey's formal explanation in net/sched/sch_tbf.c.
372 To get the maximum range, we multiply by this factor (ie. you get N
373 credits per jiffy). We want to allow a rate as low as 1 per day
374 (slowest userspace tool allows), which means
375 CREDITS_PER_JIFFY*HZ*60*60*24 < 2^32 ie.
377 #define MAX_CPJ (0xFFFFFFFF / (HZ*60*60*24))
379 /* Repeated shift and or gives us all 1s, final shift and add 1 gives
380 * us the power of 2 below the theoretical max, so GCC simply does a
382 #define _POW2_BELOW2(x) ((x)|((x)>>1))
383 #define _POW2_BELOW4(x) (_POW2_BELOW2(x)|_POW2_BELOW2((x)>>2))
384 #define _POW2_BELOW8(x) (_POW2_BELOW4(x)|_POW2_BELOW4((x)>>4))
385 #define _POW2_BELOW16(x) (_POW2_BELOW8(x)|_POW2_BELOW8((x)>>8))
386 #define _POW2_BELOW32(x) (_POW2_BELOW16(x)|_POW2_BELOW16((x)>>16))
387 #define POW2_BELOW32(x) ((_POW2_BELOW32(x)>>1) + 1)
389 #define CREDITS_PER_JIFFY POW2_BELOW32(MAX_CPJ)
391 /* Precision saver. */
392 static u32
user2credits(u32 user
)
394 /* If multiplying would overflow... */
395 if (user
> 0xFFFFFFFF / (HZ
*CREDITS_PER_JIFFY
))
397 return (user
/ XT_HASHLIMIT_SCALE
) * HZ
* CREDITS_PER_JIFFY
;
399 return (user
* HZ
* CREDITS_PER_JIFFY
) / XT_HASHLIMIT_SCALE
;
402 static void rateinfo_recalc(struct dsthash_ent
*dh
, unsigned long now
)
404 dh
->rateinfo
.credit
+= (now
- dh
->rateinfo
.prev
) * CREDITS_PER_JIFFY
;
405 if (dh
->rateinfo
.credit
> dh
->rateinfo
.credit_cap
)
406 dh
->rateinfo
.credit
= dh
->rateinfo
.credit_cap
;
407 dh
->rateinfo
.prev
= now
;
410 static void rateinfo_init(struct dsthash_ent
*dh
,
411 struct xt_hashlimit_htable
*hinfo
)
413 dh
->rateinfo
.prev
= jiffies
;
414 dh
->rateinfo
.credit
= user2credits(hinfo
->cfg
.avg
* hinfo
->cfg
.burst
);
415 dh
->rateinfo
.cost
= user2credits(hinfo
->cfg
.avg
);
416 dh
->rateinfo
.credit_cap
= dh
->rateinfo
.credit
;
419 static inline __be32
maskl(__be32 a
, unsigned int l
)
421 return l
? htonl(ntohl(a
) & ~0 << (32 - l
)) : 0;
424 #if IS_ENABLED(CONFIG_IP6_NF_IPTABLES)
425 static void hashlimit_ipv6_mask(__be32
*i
, unsigned int p
)
429 i
[0] = maskl(i
[0], p
);
430 i
[1] = i
[2] = i
[3] = 0;
433 i
[1] = maskl(i
[1], p
- 32);
437 i
[2] = maskl(i
[2], p
- 64);
441 i
[3] = maskl(i
[3], p
- 96);
450 hashlimit_init_dst(const struct xt_hashlimit_htable
*hinfo
,
451 struct dsthash_dst
*dst
,
452 const struct sk_buff
*skb
, unsigned int protoff
)
454 __be16 _ports
[2], *ports
;
458 memset(dst
, 0, sizeof(*dst
));
460 switch (hinfo
->family
) {
462 if (hinfo
->cfg
.mode
& XT_HASHLIMIT_HASH_DIP
)
463 dst
->ip
.dst
= maskl(ip_hdr(skb
)->daddr
,
465 if (hinfo
->cfg
.mode
& XT_HASHLIMIT_HASH_SIP
)
466 dst
->ip
.src
= maskl(ip_hdr(skb
)->saddr
,
469 if (!(hinfo
->cfg
.mode
&
470 (XT_HASHLIMIT_HASH_DPT
| XT_HASHLIMIT_HASH_SPT
)))
472 nexthdr
= ip_hdr(skb
)->protocol
;
474 #if IS_ENABLED(CONFIG_IP6_NF_IPTABLES)
479 if (hinfo
->cfg
.mode
& XT_HASHLIMIT_HASH_DIP
) {
480 memcpy(&dst
->ip6
.dst
, &ipv6_hdr(skb
)->daddr
,
481 sizeof(dst
->ip6
.dst
));
482 hashlimit_ipv6_mask(dst
->ip6
.dst
, hinfo
->cfg
.dstmask
);
484 if (hinfo
->cfg
.mode
& XT_HASHLIMIT_HASH_SIP
) {
485 memcpy(&dst
->ip6
.src
, &ipv6_hdr(skb
)->saddr
,
486 sizeof(dst
->ip6
.src
));
487 hashlimit_ipv6_mask(dst
->ip6
.src
, hinfo
->cfg
.srcmask
);
490 if (!(hinfo
->cfg
.mode
&
491 (XT_HASHLIMIT_HASH_DPT
| XT_HASHLIMIT_HASH_SPT
)))
493 nexthdr
= ipv6_hdr(skb
)->nexthdr
;
494 protoff
= ipv6_skip_exthdr(skb
, sizeof(struct ipv6hdr
), &nexthdr
, &frag_off
);
495 if ((int)protoff
< 0)
505 poff
= proto_ports_offset(nexthdr
);
507 ports
= skb_header_pointer(skb
, protoff
+ poff
, sizeof(_ports
),
510 _ports
[0] = _ports
[1] = 0;
515 if (hinfo
->cfg
.mode
& XT_HASHLIMIT_HASH_SPT
)
516 dst
->src_port
= ports
[0];
517 if (hinfo
->cfg
.mode
& XT_HASHLIMIT_HASH_DPT
)
518 dst
->dst_port
= ports
[1];
523 hashlimit_mt(const struct sk_buff
*skb
, struct xt_action_param
*par
)
525 const struct xt_hashlimit_mtinfo1
*info
= par
->matchinfo
;
526 struct xt_hashlimit_htable
*hinfo
= info
->hinfo
;
527 unsigned long now
= jiffies
;
528 struct dsthash_ent
*dh
;
529 struct dsthash_dst dst
;
531 if (hashlimit_init_dst(hinfo
, &dst
, skb
, par
->thoff
) < 0)
535 dh
= dsthash_find(hinfo
, &dst
);
537 dh
= dsthash_alloc_init(hinfo
, &dst
);
539 rcu_read_unlock_bh();
542 dh
->expires
= jiffies
+ msecs_to_jiffies(hinfo
->cfg
.expire
);
543 rateinfo_init(dh
, hinfo
);
545 /* update expiration timeout */
546 dh
->expires
= now
+ msecs_to_jiffies(hinfo
->cfg
.expire
);
547 rateinfo_recalc(dh
, now
);
550 if (dh
->rateinfo
.credit
>= dh
->rateinfo
.cost
) {
551 /* below the limit */
552 dh
->rateinfo
.credit
-= dh
->rateinfo
.cost
;
553 spin_unlock(&dh
->lock
);
554 rcu_read_unlock_bh();
555 return !(info
->cfg
.mode
& XT_HASHLIMIT_INVERT
);
558 spin_unlock(&dh
->lock
);
559 rcu_read_unlock_bh();
560 /* default match is underlimit - so over the limit, we need to invert */
561 return info
->cfg
.mode
& XT_HASHLIMIT_INVERT
;
568 static int hashlimit_mt_check(const struct xt_mtchk_param
*par
)
570 struct net
*net
= par
->net
;
571 struct xt_hashlimit_mtinfo1
*info
= par
->matchinfo
;
574 /* Check for overflow. */
575 if (info
->cfg
.burst
== 0 ||
576 user2credits(info
->cfg
.avg
* info
->cfg
.burst
) <
577 user2credits(info
->cfg
.avg
)) {
578 pr_info("overflow, try lower: %u/%u\n",
579 info
->cfg
.avg
, info
->cfg
.burst
);
582 if (info
->cfg
.gc_interval
== 0 || info
->cfg
.expire
== 0)
584 if (info
->name
[sizeof(info
->name
)-1] != '\0')
586 if (par
->family
== NFPROTO_IPV4
) {
587 if (info
->cfg
.srcmask
> 32 || info
->cfg
.dstmask
> 32)
590 if (info
->cfg
.srcmask
> 128 || info
->cfg
.dstmask
> 128)
594 mutex_lock(&hashlimit_mutex
);
595 info
->hinfo
= htable_find_get(net
, info
->name
, par
->family
);
596 if (info
->hinfo
== NULL
) {
597 ret
= htable_create(net
, info
, par
->family
);
599 mutex_unlock(&hashlimit_mutex
);
603 mutex_unlock(&hashlimit_mutex
);
607 static void hashlimit_mt_destroy(const struct xt_mtdtor_param
*par
)
609 const struct xt_hashlimit_mtinfo1
*info
= par
->matchinfo
;
611 htable_put(info
->hinfo
);
614 static struct xt_match hashlimit_mt_reg
[] __read_mostly
= {
618 .family
= NFPROTO_IPV4
,
619 .match
= hashlimit_mt
,
620 .matchsize
= sizeof(struct xt_hashlimit_mtinfo1
),
621 .checkentry
= hashlimit_mt_check
,
622 .destroy
= hashlimit_mt_destroy
,
625 #if IS_ENABLED(CONFIG_IP6_NF_IPTABLES)
629 .family
= NFPROTO_IPV6
,
630 .match
= hashlimit_mt
,
631 .matchsize
= sizeof(struct xt_hashlimit_mtinfo1
),
632 .checkentry
= hashlimit_mt_check
,
633 .destroy
= hashlimit_mt_destroy
,
640 static void *dl_seq_start(struct seq_file
*s
, loff_t
*pos
)
641 __acquires(htable
->lock
)
643 struct xt_hashlimit_htable
*htable
= s
->private;
644 unsigned int *bucket
;
646 spin_lock_bh(&htable
->lock
);
647 if (*pos
>= htable
->cfg
.size
)
650 bucket
= kmalloc(sizeof(unsigned int), GFP_ATOMIC
);
652 return ERR_PTR(-ENOMEM
);
658 static void *dl_seq_next(struct seq_file
*s
, void *v
, loff_t
*pos
)
660 struct xt_hashlimit_htable
*htable
= s
->private;
661 unsigned int *bucket
= (unsigned int *)v
;
664 if (*pos
>= htable
->cfg
.size
) {
671 static void dl_seq_stop(struct seq_file
*s
, void *v
)
672 __releases(htable
->lock
)
674 struct xt_hashlimit_htable
*htable
= s
->private;
675 unsigned int *bucket
= (unsigned int *)v
;
679 spin_unlock_bh(&htable
->lock
);
682 static int dl_seq_real_show(struct dsthash_ent
*ent
, u_int8_t family
,
687 spin_lock(&ent
->lock
);
688 /* recalculate to show accurate numbers */
689 rateinfo_recalc(ent
, jiffies
);
693 res
= seq_printf(s
, "%ld %pI4:%u->%pI4:%u %u %u %u\n",
694 (long)(ent
->expires
- jiffies
)/HZ
,
696 ntohs(ent
->dst
.src_port
),
698 ntohs(ent
->dst
.dst_port
),
699 ent
->rateinfo
.credit
, ent
->rateinfo
.credit_cap
,
702 #if IS_ENABLED(CONFIG_IP6_NF_IPTABLES)
704 res
= seq_printf(s
, "%ld %pI6:%u->%pI6:%u %u %u %u\n",
705 (long)(ent
->expires
- jiffies
)/HZ
,
707 ntohs(ent
->dst
.src_port
),
709 ntohs(ent
->dst
.dst_port
),
710 ent
->rateinfo
.credit
, ent
->rateinfo
.credit_cap
,
718 spin_unlock(&ent
->lock
);
722 static int dl_seq_show(struct seq_file
*s
, void *v
)
724 struct xt_hashlimit_htable
*htable
= s
->private;
725 unsigned int *bucket
= (unsigned int *)v
;
726 struct dsthash_ent
*ent
;
727 struct hlist_node
*pos
;
729 if (!hlist_empty(&htable
->hash
[*bucket
])) {
730 hlist_for_each_entry(ent
, pos
, &htable
->hash
[*bucket
], node
)
731 if (dl_seq_real_show(ent
, htable
->family
, s
))
737 static const struct seq_operations dl_seq_ops
= {
738 .start
= dl_seq_start
,
744 static int dl_proc_open(struct inode
*inode
, struct file
*file
)
746 int ret
= seq_open(file
, &dl_seq_ops
);
749 struct seq_file
*sf
= file
->private_data
;
750 sf
->private = PDE(inode
)->data
;
755 static const struct file_operations dl_file_ops
= {
756 .owner
= THIS_MODULE
,
757 .open
= dl_proc_open
,
760 .release
= seq_release
763 static int __net_init
hashlimit_proc_net_init(struct net
*net
)
765 struct hashlimit_net
*hashlimit_net
= hashlimit_pernet(net
);
767 hashlimit_net
->ipt_hashlimit
= proc_mkdir("ipt_hashlimit", net
->proc_net
);
768 if (!hashlimit_net
->ipt_hashlimit
)
770 #if IS_ENABLED(CONFIG_IP6_NF_IPTABLES)
771 hashlimit_net
->ip6t_hashlimit
= proc_mkdir("ip6t_hashlimit", net
->proc_net
);
772 if (!hashlimit_net
->ip6t_hashlimit
) {
773 proc_net_remove(net
, "ipt_hashlimit");
780 static void __net_exit
hashlimit_proc_net_exit(struct net
*net
)
782 proc_net_remove(net
, "ipt_hashlimit");
783 #if IS_ENABLED(CONFIG_IP6_NF_IPTABLES)
784 proc_net_remove(net
, "ip6t_hashlimit");
788 static int __net_init
hashlimit_net_init(struct net
*net
)
790 struct hashlimit_net
*hashlimit_net
= hashlimit_pernet(net
);
792 INIT_HLIST_HEAD(&hashlimit_net
->htables
);
793 return hashlimit_proc_net_init(net
);
796 static void __net_exit
hashlimit_net_exit(struct net
*net
)
798 struct hashlimit_net
*hashlimit_net
= hashlimit_pernet(net
);
800 BUG_ON(!hlist_empty(&hashlimit_net
->htables
));
801 hashlimit_proc_net_exit(net
);
804 static struct pernet_operations hashlimit_net_ops
= {
805 .init
= hashlimit_net_init
,
806 .exit
= hashlimit_net_exit
,
807 .id
= &hashlimit_net_id
,
808 .size
= sizeof(struct hashlimit_net
),
811 static int __init
hashlimit_mt_init(void)
815 err
= register_pernet_subsys(&hashlimit_net_ops
);
818 err
= xt_register_matches(hashlimit_mt_reg
,
819 ARRAY_SIZE(hashlimit_mt_reg
));
824 hashlimit_cachep
= kmem_cache_create("xt_hashlimit",
825 sizeof(struct dsthash_ent
), 0, 0,
827 if (!hashlimit_cachep
) {
828 pr_warning("unable to create slab cache\n");
834 xt_unregister_matches(hashlimit_mt_reg
, ARRAY_SIZE(hashlimit_mt_reg
));
836 unregister_pernet_subsys(&hashlimit_net_ops
);
841 static void __exit
hashlimit_mt_exit(void)
843 xt_unregister_matches(hashlimit_mt_reg
, ARRAY_SIZE(hashlimit_mt_reg
));
844 unregister_pernet_subsys(&hashlimit_net_ops
);
847 kmem_cache_destroy(hashlimit_cachep
);
850 module_init(hashlimit_mt_init
);
851 module_exit(hashlimit_mt_exit
);