Commit | Line | Data |
---|---|---|
09e410de JE |
1 | /* |
2 | * xt_hashlimit - Netfilter module to limit the number of packets per time | |
3ad2f3fb | 3 | * separately for each hashbucket (sourceip/sourceport/dstip/dstport) |
1da177e4 | 4 | * |
09e410de | 5 | * (C) 2003-2004 by Harald Welte <laforge@netfilter.org> |
f229f6ce | 6 | * (C) 2006-2012 Patrick McHardy <kaber@trash.net> |
09e410de | 7 | * Copyright © CC Computer Consultants GmbH, 2007 - 2008 |
1da177e4 LT |
8 | * |
9 | * Development of this code was funded by Astaro AG, http://www.astaro.com/ | |
1da177e4 | 10 | */ |
8bee4bad | 11 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
1da177e4 | 12 | #include <linux/module.h> |
1da177e4 LT |
13 | #include <linux/spinlock.h> |
14 | #include <linux/random.h> | |
15 | #include <linux/jhash.h> | |
16 | #include <linux/slab.h> | |
17 | #include <linux/vmalloc.h> | |
1da177e4 LT |
18 | #include <linux/proc_fs.h> |
19 | #include <linux/seq_file.h> | |
20 | #include <linux/list.h> | |
39b46fc6 | 21 | #include <linux/skbuff.h> |
d7fe0f24 | 22 | #include <linux/mm.h> |
39b46fc6 PM |
23 | #include <linux/in.h> |
24 | #include <linux/ip.h> | |
c0cd1156 | 25 | #if IS_ENABLED(CONFIG_IP6_NF_IPTABLES) |
39b46fc6 | 26 | #include <linux/ipv6.h> |
193b23c5 | 27 | #include <net/ipv6.h> |
7b21e09d ED |
28 | #endif |
29 | ||
457c4cbc | 30 | #include <net/net_namespace.h> |
e89fc3f1 | 31 | #include <net/netns/generic.h> |
1da177e4 | 32 | |
39b46fc6 | 33 | #include <linux/netfilter/x_tables.h> |
1da177e4 | 34 | #include <linux/netfilter_ipv4/ip_tables.h> |
39b46fc6 PM |
35 | #include <linux/netfilter_ipv6/ip6_tables.h> |
36 | #include <linux/netfilter/xt_hashlimit.h> | |
14cc3e2b | 37 | #include <linux/mutex.h> |
1da177e4 LT |
38 | |
39 | MODULE_LICENSE("GPL"); | |
40 | MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>"); | |
408ffaa4 | 41 | MODULE_AUTHOR("Jan Engelhardt <jengelh@medozas.de>"); |
2ae15b64 | 42 | MODULE_DESCRIPTION("Xtables: per hash-bucket rate-limit match"); |
39b46fc6 PM |
43 | MODULE_ALIAS("ipt_hashlimit"); |
44 | MODULE_ALIAS("ip6t_hashlimit"); | |
1da177e4 | 45 | |
e89fc3f1 AD |
46 | struct hashlimit_net { |
47 | struct hlist_head htables; | |
48 | struct proc_dir_entry *ipt_hashlimit; | |
49 | struct proc_dir_entry *ip6t_hashlimit; | |
50 | }; | |
51 | ||
52 | static int hashlimit_net_id; | |
53 | static inline struct hashlimit_net *hashlimit_pernet(struct net *net) | |
54 | { | |
55 | return net_generic(net, hashlimit_net_id); | |
56 | } | |
57 | ||
1da177e4 | 58 | /* need to declare this at the top */ |
da7071d7 | 59 | static const struct file_operations dl_file_ops; |
1da177e4 LT |
60 | |
61 | /* hash table crap */ | |
1da177e4 | 62 | struct dsthash_dst { |
39b46fc6 PM |
63 | union { |
64 | struct { | |
65 | __be32 src; | |
66 | __be32 dst; | |
67 | } ip; | |
c0cd1156 | 68 | #if IS_ENABLED(CONFIG_IP6_NF_IPTABLES) |
39b46fc6 PM |
69 | struct { |
70 | __be32 src[4]; | |
71 | __be32 dst[4]; | |
72 | } ip6; | |
7b21e09d | 73 | #endif |
09e410de | 74 | }; |
6a19d614 AV |
75 | __be16 src_port; |
76 | __be16 dst_port; | |
1da177e4 LT |
77 | }; |
78 | ||
79 | struct dsthash_ent { | |
80 | /* static / read-only parts in the beginning */ | |
81 | struct hlist_node node; | |
82 | struct dsthash_dst dst; | |
83 | ||
84 | /* modified structure members in the end */ | |
02e4eb75 | 85 | spinlock_t lock; |
1da177e4 LT |
86 | unsigned long expires; /* precalculated expiry time */ |
87 | struct { | |
88 | unsigned long prev; /* last modification */ | |
89 | u_int32_t credit; | |
90 | u_int32_t credit_cap, cost; | |
91 | } rateinfo; | |
02e4eb75 | 92 | struct rcu_head rcu; |
1da177e4 LT |
93 | }; |
94 | ||
39b46fc6 | 95 | struct xt_hashlimit_htable { |
1da177e4 | 96 | struct hlist_node node; /* global list of all htables */ |
2eff25c1 | 97 | int use; |
76108cea | 98 | u_int8_t family; |
89bc7a0f | 99 | bool rnd_initialized; |
1da177e4 | 100 | |
09e410de | 101 | struct hashlimit_cfg1 cfg; /* config */ |
1da177e4 LT |
102 | |
103 | /* used internally */ | |
104 | spinlock_t lock; /* lock for list_head */ | |
105 | u_int32_t rnd; /* random seed for hash */ | |
39b46fc6 | 106 | unsigned int count; /* number entries in table */ |
1da177e4 | 107 | struct timer_list timer; /* timer for gc */ |
1da177e4 LT |
108 | |
109 | /* seq_file stuff */ | |
110 | struct proc_dir_entry *pde; | |
14b872f0 | 111 | const char *name; |
e89fc3f1 | 112 | struct net *net; |
1da177e4 LT |
113 | |
114 | struct hlist_head hash[0]; /* hashtable itself */ | |
115 | }; | |
116 | ||
2eff25c1 | 117 | static DEFINE_MUTEX(hashlimit_mutex); /* protects htables list */ |
e18b890b | 118 | static struct kmem_cache *hashlimit_cachep __read_mostly; |
1da177e4 | 119 | |
1d93a9cb | 120 | static inline bool dst_cmp(const struct dsthash_ent *ent, |
a47362a2 | 121 | const struct dsthash_dst *b) |
1da177e4 | 122 | { |
39b46fc6 | 123 | return !memcmp(&ent->dst, b, sizeof(ent->dst)); |
1da177e4 LT |
124 | } |
125 | ||
39b46fc6 PM |
126 | static u_int32_t |
127 | hash_dst(const struct xt_hashlimit_htable *ht, const struct dsthash_dst *dst) | |
1da177e4 | 128 | { |
e2f82ac3 ED |
129 | u_int32_t hash = jhash2((const u32 *)dst, |
130 | sizeof(*dst)/sizeof(u32), | |
131 | ht->rnd); | |
132 | /* | |
133 | * Instead of returning hash % ht->cfg.size (implying a divide) | |
134 | * we return the high 32 bits of the (hash * ht->cfg.size) that will | |
135 | * give results between [0 and cfg.size-1] and same hash distribution, | |
136 | * but using a multiply, less expensive than a divide | |
137 | */ | |
138 | return ((u64)hash * ht->cfg.size) >> 32; | |
1da177e4 LT |
139 | } |
140 | ||
39b46fc6 | 141 | static struct dsthash_ent * |
a47362a2 JE |
142 | dsthash_find(const struct xt_hashlimit_htable *ht, |
143 | const struct dsthash_dst *dst) | |
1da177e4 LT |
144 | { |
145 | struct dsthash_ent *ent; | |
1da177e4 LT |
146 | u_int32_t hash = hash_dst(ht, dst); |
147 | ||
39b46fc6 | 148 | if (!hlist_empty(&ht->hash[hash])) { |
b67bfe0d | 149 | hlist_for_each_entry_rcu(ent, &ht->hash[hash], node) |
02e4eb75 ED |
150 | if (dst_cmp(ent, dst)) { |
151 | spin_lock(&ent->lock); | |
1da177e4 | 152 | return ent; |
02e4eb75 | 153 | } |
39b46fc6 | 154 | } |
1da177e4 LT |
155 | return NULL; |
156 | } | |
157 | ||
158 | /* allocate dsthash_ent, initialize dst, put in htable and lock it */ | |
159 | static struct dsthash_ent * | |
a47362a2 | 160 | dsthash_alloc_init(struct xt_hashlimit_htable *ht, |
09181842 | 161 | const struct dsthash_dst *dst, bool *race) |
1da177e4 LT |
162 | { |
163 | struct dsthash_ent *ent; | |
164 | ||
02e4eb75 | 165 | spin_lock(&ht->lock); |
09181842 PNA |
166 | |
167 | /* Two or more packets may race to create the same entry in the | |
168 | * hashtable, double check if this packet lost race. | |
169 | */ | |
170 | ent = dsthash_find(ht, dst); | |
171 | if (ent != NULL) { | |
172 | spin_unlock(&ht->lock); | |
173 | *race = true; | |
174 | return ent; | |
175 | } | |
176 | ||
1da177e4 LT |
177 | /* initialize hash with random val at the time we allocate |
178 | * the first hashtable entry */ | |
02e4eb75 | 179 | if (unlikely(!ht->rnd_initialized)) { |
af07d241 | 180 | get_random_bytes(&ht->rnd, sizeof(ht->rnd)); |
89bc7a0f | 181 | ht->rnd_initialized = true; |
bf0857ea | 182 | } |
1da177e4 | 183 | |
39b46fc6 | 184 | if (ht->cfg.max && ht->count >= ht->cfg.max) { |
1da177e4 | 185 | /* FIXME: do something. question is what.. */ |
e87cc472 | 186 | net_err_ratelimited("max count of %u reached\n", ht->cfg.max); |
02e4eb75 ED |
187 | ent = NULL; |
188 | } else | |
189 | ent = kmem_cache_alloc(hashlimit_cachep, GFP_ATOMIC); | |
0a9ee813 | 190 | if (ent) { |
02e4eb75 ED |
191 | memcpy(&ent->dst, dst, sizeof(ent->dst)); |
192 | spin_lock_init(&ent->lock); | |
1da177e4 | 193 | |
02e4eb75 ED |
194 | spin_lock(&ent->lock); |
195 | hlist_add_head_rcu(&ent->node, &ht->hash[hash_dst(ht, dst)]); | |
196 | ht->count++; | |
197 | } | |
198 | spin_unlock(&ht->lock); | |
1da177e4 LT |
199 | return ent; |
200 | } | |
201 | ||
02e4eb75 ED |
202 | static void dsthash_free_rcu(struct rcu_head *head) |
203 | { | |
204 | struct dsthash_ent *ent = container_of(head, struct dsthash_ent, rcu); | |
205 | ||
206 | kmem_cache_free(hashlimit_cachep, ent); | |
207 | } | |
208 | ||
39b46fc6 PM |
209 | static inline void |
210 | dsthash_free(struct xt_hashlimit_htable *ht, struct dsthash_ent *ent) | |
1da177e4 | 211 | { |
02e4eb75 ED |
212 | hlist_del_rcu(&ent->node); |
213 | call_rcu_bh(&ent->rcu, dsthash_free_rcu); | |
39b46fc6 | 214 | ht->count--; |
1da177e4 LT |
215 | } |
216 | static void htable_gc(unsigned long htlong); | |
217 | ||
e89fc3f1 AD |
218 | static int htable_create(struct net *net, struct xt_hashlimit_mtinfo1 *minfo, |
219 | u_int8_t family) | |
09e410de | 220 | { |
e89fc3f1 | 221 | struct hashlimit_net *hashlimit_net = hashlimit_pernet(net); |
09e410de JE |
222 | struct xt_hashlimit_htable *hinfo; |
223 | unsigned int size; | |
224 | unsigned int i; | |
225 | ||
226 | if (minfo->cfg.size) { | |
227 | size = minfo->cfg.size; | |
228 | } else { | |
4481374c | 229 | size = (totalram_pages << PAGE_SHIFT) / 16384 / |
09e410de | 230 | sizeof(struct list_head); |
4481374c | 231 | if (totalram_pages > 1024 * 1024 * 1024 / PAGE_SIZE) |
09e410de JE |
232 | size = 8192; |
233 | if (size < 16) | |
234 | size = 16; | |
235 | } | |
236 | /* FIXME: don't use vmalloc() here or anywhere else -HW */ | |
237 | hinfo = vmalloc(sizeof(struct xt_hashlimit_htable) + | |
238 | sizeof(struct list_head) * size); | |
85bc3f38 | 239 | if (hinfo == NULL) |
4a5a5c73 | 240 | return -ENOMEM; |
09e410de JE |
241 | minfo->hinfo = hinfo; |
242 | ||
243 | /* copy match config into hashtable config */ | |
244 | memcpy(&hinfo->cfg, &minfo->cfg, sizeof(hinfo->cfg)); | |
245 | hinfo->cfg.size = size; | |
246 | if (hinfo->cfg.max == 0) | |
247 | hinfo->cfg.max = 8 * hinfo->cfg.size; | |
248 | else if (hinfo->cfg.max < hinfo->cfg.size) | |
249 | hinfo->cfg.max = hinfo->cfg.size; | |
250 | ||
251 | for (i = 0; i < hinfo->cfg.size; i++) | |
252 | INIT_HLIST_HEAD(&hinfo->hash[i]); | |
253 | ||
2eff25c1 | 254 | hinfo->use = 1; |
09e410de JE |
255 | hinfo->count = 0; |
256 | hinfo->family = family; | |
89bc7a0f | 257 | hinfo->rnd_initialized = false; |
14b872f0 AV |
258 | hinfo->name = kstrdup(minfo->name, GFP_KERNEL); |
259 | if (!hinfo->name) { | |
260 | vfree(hinfo); | |
261 | return -ENOMEM; | |
262 | } | |
09e410de JE |
263 | spin_lock_init(&hinfo->lock); |
264 | ||
ee999d8b JE |
265 | hinfo->pde = proc_create_data(minfo->name, 0, |
266 | (family == NFPROTO_IPV4) ? | |
e89fc3f1 | 267 | hashlimit_net->ipt_hashlimit : hashlimit_net->ip6t_hashlimit, |
ee999d8b | 268 | &dl_file_ops, hinfo); |
09e410de | 269 | if (hinfo->pde == NULL) { |
14b872f0 | 270 | kfree(hinfo->name); |
09e410de | 271 | vfree(hinfo); |
4a5a5c73 | 272 | return -ENOMEM; |
09e410de | 273 | } |
e89fc3f1 | 274 | hinfo->net = net; |
09e410de JE |
275 | |
276 | setup_timer(&hinfo->timer, htable_gc, (unsigned long)hinfo); | |
277 | hinfo->timer.expires = jiffies + msecs_to_jiffies(hinfo->cfg.gc_interval); | |
278 | add_timer(&hinfo->timer); | |
279 | ||
e89fc3f1 | 280 | hlist_add_head(&hinfo->node, &hashlimit_net->htables); |
09e410de JE |
281 | |
282 | return 0; | |
283 | } | |
284 | ||
a47362a2 JE |
285 | static bool select_all(const struct xt_hashlimit_htable *ht, |
286 | const struct dsthash_ent *he) | |
1da177e4 LT |
287 | { |
288 | return 1; | |
289 | } | |
290 | ||
a47362a2 JE |
291 | static bool select_gc(const struct xt_hashlimit_htable *ht, |
292 | const struct dsthash_ent *he) | |
1da177e4 | 293 | { |
cbebc51f | 294 | return time_after_eq(jiffies, he->expires); |
1da177e4 LT |
295 | } |
296 | ||
39b46fc6 | 297 | static void htable_selective_cleanup(struct xt_hashlimit_htable *ht, |
a47362a2 JE |
298 | bool (*select)(const struct xt_hashlimit_htable *ht, |
299 | const struct dsthash_ent *he)) | |
1da177e4 | 300 | { |
39b46fc6 | 301 | unsigned int i; |
1da177e4 LT |
302 | |
303 | /* lock hash table and iterate over it */ | |
304 | spin_lock_bh(&ht->lock); | |
305 | for (i = 0; i < ht->cfg.size; i++) { | |
306 | struct dsthash_ent *dh; | |
b67bfe0d SL |
307 | struct hlist_node *n; |
308 | hlist_for_each_entry_safe(dh, n, &ht->hash[i], node) { | |
1da177e4 | 309 | if ((*select)(ht, dh)) |
39b46fc6 | 310 | dsthash_free(ht, dh); |
1da177e4 LT |
311 | } |
312 | } | |
313 | spin_unlock_bh(&ht->lock); | |
314 | } | |
315 | ||
316 | /* hash table garbage collector, run by timer */ | |
317 | static void htable_gc(unsigned long htlong) | |
318 | { | |
39b46fc6 | 319 | struct xt_hashlimit_htable *ht = (struct xt_hashlimit_htable *)htlong; |
1da177e4 LT |
320 | |
321 | htable_selective_cleanup(ht, select_gc); | |
322 | ||
323 | /* re-add the timer accordingly */ | |
324 | ht->timer.expires = jiffies + msecs_to_jiffies(ht->cfg.gc_interval); | |
325 | add_timer(&ht->timer); | |
326 | } | |
327 | ||
b4ef4ce0 | 328 | static void htable_remove_proc_entry(struct xt_hashlimit_htable *hinfo) |
1da177e4 | 329 | { |
e89fc3f1 AD |
330 | struct hashlimit_net *hashlimit_net = hashlimit_pernet(hinfo->net); |
331 | struct proc_dir_entry *parent; | |
332 | ||
e89fc3f1 AD |
333 | if (hinfo->family == NFPROTO_IPV4) |
334 | parent = hashlimit_net->ipt_hashlimit; | |
335 | else | |
336 | parent = hashlimit_net->ip6t_hashlimit; | |
32263dd1 | 337 | |
b4ef4ce0 | 338 | if (parent != NULL) |
14b872f0 | 339 | remove_proc_entry(hinfo->name, parent); |
b4ef4ce0 | 340 | } |
32263dd1 | 341 | |
b4ef4ce0 SP |
342 | static void htable_destroy(struct xt_hashlimit_htable *hinfo) |
343 | { | |
344 | del_timer_sync(&hinfo->timer); | |
345 | htable_remove_proc_entry(hinfo); | |
1da177e4 | 346 | htable_selective_cleanup(hinfo, select_all); |
14b872f0 | 347 | kfree(hinfo->name); |
1da177e4 LT |
348 | vfree(hinfo); |
349 | } | |
350 | ||
e89fc3f1 AD |
351 | static struct xt_hashlimit_htable *htable_find_get(struct net *net, |
352 | const char *name, | |
76108cea | 353 | u_int8_t family) |
1da177e4 | 354 | { |
e89fc3f1 | 355 | struct hashlimit_net *hashlimit_net = hashlimit_pernet(net); |
39b46fc6 | 356 | struct xt_hashlimit_htable *hinfo; |
1da177e4 | 357 | |
b67bfe0d | 358 | hlist_for_each_entry(hinfo, &hashlimit_net->htables, node) { |
14b872f0 | 359 | if (!strcmp(name, hinfo->name) && |
39b46fc6 | 360 | hinfo->family == family) { |
2eff25c1 | 361 | hinfo->use++; |
1da177e4 LT |
362 | return hinfo; |
363 | } | |
364 | } | |
1da177e4 LT |
365 | return NULL; |
366 | } | |
367 | ||
39b46fc6 | 368 | static void htable_put(struct xt_hashlimit_htable *hinfo) |
1da177e4 | 369 | { |
2eff25c1 PM |
370 | mutex_lock(&hashlimit_mutex); |
371 | if (--hinfo->use == 0) { | |
1da177e4 | 372 | hlist_del(&hinfo->node); |
1da177e4 LT |
373 | htable_destroy(hinfo); |
374 | } | |
2eff25c1 | 375 | mutex_unlock(&hashlimit_mutex); |
1da177e4 LT |
376 | } |
377 | ||
1da177e4 LT |
378 | /* The algorithm used is the Simple Token Bucket Filter (TBF) |
379 | * see net/sched/sch_tbf.c in the linux source tree | |
380 | */ | |
381 | ||
382 | /* Rusty: This is my (non-mathematically-inclined) understanding of | |
383 | this algorithm. The `average rate' in jiffies becomes your initial | |
384 | amount of credit `credit' and the most credit you can ever have | |
385 | `credit_cap'. The `peak rate' becomes the cost of passing the | |
386 | test, `cost'. | |
387 | ||
388 | `prev' tracks the last packet hit: you gain one credit per jiffy. | |
389 | If you get credit balance more than this, the extra credit is | |
390 | discarded. Every time the match passes, you lose `cost' credits; | |
391 | if you don't have that many, the test fails. | |
392 | ||
393 | See Alexey's formal explanation in net/sched/sch_tbf.c. | |
394 | ||
395 | To get the maximum range, we multiply by this factor (ie. you get N | |
396 | credits per jiffy). We want to allow a rate as low as 1 per day | |
397 | (slowest userspace tool allows), which means | |
398 | CREDITS_PER_JIFFY*HZ*60*60*24 < 2^32 ie. | |
399 | */ | |
400 | #define MAX_CPJ (0xFFFFFFFF / (HZ*60*60*24)) | |
401 | ||
402 | /* Repeated shift and or gives us all 1s, final shift and add 1 gives | |
403 | * us the power of 2 below the theoretical max, so GCC simply does a | |
404 | * shift. */ | |
405 | #define _POW2_BELOW2(x) ((x)|((x)>>1)) | |
406 | #define _POW2_BELOW4(x) (_POW2_BELOW2(x)|_POW2_BELOW2((x)>>2)) | |
407 | #define _POW2_BELOW8(x) (_POW2_BELOW4(x)|_POW2_BELOW4((x)>>4)) | |
408 | #define _POW2_BELOW16(x) (_POW2_BELOW8(x)|_POW2_BELOW8((x)>>8)) | |
409 | #define _POW2_BELOW32(x) (_POW2_BELOW16(x)|_POW2_BELOW16((x)>>16)) | |
410 | #define POW2_BELOW32(x) ((_POW2_BELOW32(x)>>1) + 1) | |
411 | ||
412 | #define CREDITS_PER_JIFFY POW2_BELOW32(MAX_CPJ) | |
413 | ||
0197dee7 FW |
414 | /* in byte mode, the lowest possible rate is one packet/second. |
415 | * credit_cap is used as a counter that tells us how many times we can | |
416 | * refill the "credits available" counter when it becomes empty. | |
417 | */ | |
418 | #define MAX_CPJ_BYTES (0xFFFFFFFF / HZ) | |
419 | #define CREDITS_PER_JIFFY_BYTES POW2_BELOW32(MAX_CPJ_BYTES) | |
420 | ||
421 | static u32 xt_hashlimit_len_to_chunks(u32 len) | |
422 | { | |
423 | return (len >> XT_HASHLIMIT_BYTE_SHIFT) + 1; | |
424 | } | |
425 | ||
1da177e4 | 426 | /* Precision saver. */ |
7a909ac7 | 427 | static u32 user2credits(u32 user) |
1da177e4 LT |
428 | { |
429 | /* If multiplying would overflow... */ | |
430 | if (user > 0xFFFFFFFF / (HZ*CREDITS_PER_JIFFY)) | |
431 | /* Divide first. */ | |
39b46fc6 | 432 | return (user / XT_HASHLIMIT_SCALE) * HZ * CREDITS_PER_JIFFY; |
1da177e4 | 433 | |
39b46fc6 | 434 | return (user * HZ * CREDITS_PER_JIFFY) / XT_HASHLIMIT_SCALE; |
1da177e4 LT |
435 | } |
436 | ||
0197dee7 | 437 | static u32 user2credits_byte(u32 user) |
1da177e4 | 438 | { |
0197dee7 FW |
439 | u64 us = user; |
440 | us *= HZ * CREDITS_PER_JIFFY_BYTES; | |
441 | return (u32) (us >> 32); | |
442 | } | |
443 | ||
444 | static void rateinfo_recalc(struct dsthash_ent *dh, unsigned long now, u32 mode) | |
445 | { | |
446 | unsigned long delta = now - dh->rateinfo.prev; | |
447 | u32 cap; | |
448 | ||
449 | if (delta == 0) | |
450 | return; | |
451 | ||
39b46fc6 | 452 | dh->rateinfo.prev = now; |
0197dee7 FW |
453 | |
454 | if (mode & XT_HASHLIMIT_BYTES) { | |
455 | u32 tmp = dh->rateinfo.credit; | |
456 | dh->rateinfo.credit += CREDITS_PER_JIFFY_BYTES * delta; | |
457 | cap = CREDITS_PER_JIFFY_BYTES * HZ; | |
458 | if (tmp >= dh->rateinfo.credit) {/* overflow */ | |
459 | dh->rateinfo.credit = cap; | |
460 | return; | |
461 | } | |
462 | } else { | |
463 | dh->rateinfo.credit += delta * CREDITS_PER_JIFFY; | |
464 | cap = dh->rateinfo.credit_cap; | |
465 | } | |
466 | if (dh->rateinfo.credit > cap) | |
467 | dh->rateinfo.credit = cap; | |
39b46fc6 PM |
468 | } |
469 | ||
817e076f FW |
470 | static void rateinfo_init(struct dsthash_ent *dh, |
471 | struct xt_hashlimit_htable *hinfo) | |
472 | { | |
473 | dh->rateinfo.prev = jiffies; | |
0197dee7 FW |
474 | if (hinfo->cfg.mode & XT_HASHLIMIT_BYTES) { |
475 | dh->rateinfo.credit = CREDITS_PER_JIFFY_BYTES * HZ; | |
476 | dh->rateinfo.cost = user2credits_byte(hinfo->cfg.avg); | |
477 | dh->rateinfo.credit_cap = hinfo->cfg.burst; | |
478 | } else { | |
479 | dh->rateinfo.credit = user2credits(hinfo->cfg.avg * | |
480 | hinfo->cfg.burst); | |
481 | dh->rateinfo.cost = user2credits(hinfo->cfg.avg); | |
482 | dh->rateinfo.credit_cap = dh->rateinfo.credit; | |
483 | } | |
817e076f FW |
484 | } |
485 | ||
09e410de JE |
486 | static inline __be32 maskl(__be32 a, unsigned int l) |
487 | { | |
1b9b70ea | 488 | return l ? htonl(ntohl(a) & ~0 << (32 - l)) : 0; |
09e410de JE |
489 | } |
490 | ||
c0cd1156 | 491 | #if IS_ENABLED(CONFIG_IP6_NF_IPTABLES) |
09e410de JE |
492 | static void hashlimit_ipv6_mask(__be32 *i, unsigned int p) |
493 | { | |
494 | switch (p) { | |
1b9b70ea | 495 | case 0 ... 31: |
09e410de JE |
496 | i[0] = maskl(i[0], p); |
497 | i[1] = i[2] = i[3] = 0; | |
498 | break; | |
1b9b70ea | 499 | case 32 ... 63: |
09e410de JE |
500 | i[1] = maskl(i[1], p - 32); |
501 | i[2] = i[3] = 0; | |
502 | break; | |
1b9b70ea | 503 | case 64 ... 95: |
09e410de JE |
504 | i[2] = maskl(i[2], p - 64); |
505 | i[3] = 0; | |
8f599229 | 506 | break; |
1b9b70ea | 507 | case 96 ... 127: |
09e410de JE |
508 | i[3] = maskl(i[3], p - 96); |
509 | break; | |
510 | case 128: | |
511 | break; | |
512 | } | |
513 | } | |
3ed5df44 | 514 | #endif |
09e410de | 515 | |
39b46fc6 | 516 | static int |
a47362a2 JE |
517 | hashlimit_init_dst(const struct xt_hashlimit_htable *hinfo, |
518 | struct dsthash_dst *dst, | |
39b46fc6 PM |
519 | const struct sk_buff *skb, unsigned int protoff) |
520 | { | |
521 | __be16 _ports[2], *ports; | |
193b23c5 | 522 | u8 nexthdr; |
aca071c1 | 523 | int poff; |
39b46fc6 PM |
524 | |
525 | memset(dst, 0, sizeof(*dst)); | |
526 | ||
527 | switch (hinfo->family) { | |
ee999d8b | 528 | case NFPROTO_IPV4: |
39b46fc6 | 529 | if (hinfo->cfg.mode & XT_HASHLIMIT_HASH_DIP) |
09e410de JE |
530 | dst->ip.dst = maskl(ip_hdr(skb)->daddr, |
531 | hinfo->cfg.dstmask); | |
39b46fc6 | 532 | if (hinfo->cfg.mode & XT_HASHLIMIT_HASH_SIP) |
09e410de JE |
533 | dst->ip.src = maskl(ip_hdr(skb)->saddr, |
534 | hinfo->cfg.srcmask); | |
39b46fc6 PM |
535 | |
536 | if (!(hinfo->cfg.mode & | |
537 | (XT_HASHLIMIT_HASH_DPT | XT_HASHLIMIT_HASH_SPT))) | |
538 | return 0; | |
eddc9ec5 | 539 | nexthdr = ip_hdr(skb)->protocol; |
39b46fc6 | 540 | break; |
c0cd1156 | 541 | #if IS_ENABLED(CONFIG_IP6_NF_IPTABLES) |
ee999d8b | 542 | case NFPROTO_IPV6: |
412662d2 SR |
543 | { |
544 | __be16 frag_off; | |
545 | ||
09e410de JE |
546 | if (hinfo->cfg.mode & XT_HASHLIMIT_HASH_DIP) { |
547 | memcpy(&dst->ip6.dst, &ipv6_hdr(skb)->daddr, | |
548 | sizeof(dst->ip6.dst)); | |
549 | hashlimit_ipv6_mask(dst->ip6.dst, hinfo->cfg.dstmask); | |
550 | } | |
551 | if (hinfo->cfg.mode & XT_HASHLIMIT_HASH_SIP) { | |
552 | memcpy(&dst->ip6.src, &ipv6_hdr(skb)->saddr, | |
553 | sizeof(dst->ip6.src)); | |
554 | hashlimit_ipv6_mask(dst->ip6.src, hinfo->cfg.srcmask); | |
555 | } | |
39b46fc6 PM |
556 | |
557 | if (!(hinfo->cfg.mode & | |
558 | (XT_HASHLIMIT_HASH_DPT | XT_HASHLIMIT_HASH_SPT))) | |
559 | return 0; | |
193b23c5 | 560 | nexthdr = ipv6_hdr(skb)->nexthdr; |
75f2811c | 561 | protoff = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), &nexthdr, &frag_off); |
193b23c5 | 562 | if ((int)protoff < 0) |
39b46fc6 PM |
563 | return -1; |
564 | break; | |
412662d2 | 565 | } |
39b46fc6 PM |
566 | #endif |
567 | default: | |
568 | BUG(); | |
569 | return 0; | |
570 | } | |
571 | ||
aca071c1 CG |
572 | poff = proto_ports_offset(nexthdr); |
573 | if (poff >= 0) { | |
574 | ports = skb_header_pointer(skb, protoff + poff, sizeof(_ports), | |
39b46fc6 | 575 | &_ports); |
aca071c1 | 576 | } else { |
39b46fc6 PM |
577 | _ports[0] = _ports[1] = 0; |
578 | ports = _ports; | |
39b46fc6 PM |
579 | } |
580 | if (!ports) | |
581 | return -1; | |
582 | if (hinfo->cfg.mode & XT_HASHLIMIT_HASH_SPT) | |
583 | dst->src_port = ports[0]; | |
584 | if (hinfo->cfg.mode & XT_HASHLIMIT_HASH_DPT) | |
585 | dst->dst_port = ports[1]; | |
586 | return 0; | |
1da177e4 LT |
587 | } |
588 | ||
0197dee7 FW |
589 | static u32 hashlimit_byte_cost(unsigned int len, struct dsthash_ent *dh) |
590 | { | |
591 | u64 tmp = xt_hashlimit_len_to_chunks(len); | |
592 | tmp = tmp * dh->rateinfo.cost; | |
593 | ||
594 | if (unlikely(tmp > CREDITS_PER_JIFFY_BYTES * HZ)) | |
595 | tmp = CREDITS_PER_JIFFY_BYTES * HZ; | |
596 | ||
597 | if (dh->rateinfo.credit < tmp && dh->rateinfo.credit_cap) { | |
598 | dh->rateinfo.credit_cap--; | |
599 | dh->rateinfo.credit = CREDITS_PER_JIFFY_BYTES * HZ; | |
600 | } | |
601 | return (u32) tmp; | |
602 | } | |
603 | ||
ccb79bdc | 604 | static bool |
62fc8051 | 605 | hashlimit_mt(const struct sk_buff *skb, struct xt_action_param *par) |
09e410de | 606 | { |
f7108a20 | 607 | const struct xt_hashlimit_mtinfo1 *info = par->matchinfo; |
09e410de JE |
608 | struct xt_hashlimit_htable *hinfo = info->hinfo; |
609 | unsigned long now = jiffies; | |
610 | struct dsthash_ent *dh; | |
611 | struct dsthash_dst dst; | |
09181842 | 612 | bool race = false; |
0197dee7 | 613 | u32 cost; |
09e410de | 614 | |
f7108a20 | 615 | if (hashlimit_init_dst(hinfo, &dst, skb, par->thoff) < 0) |
09e410de JE |
616 | goto hotdrop; |
617 | ||
02e4eb75 | 618 | rcu_read_lock_bh(); |
09e410de JE |
619 | dh = dsthash_find(hinfo, &dst); |
620 | if (dh == NULL) { | |
09181842 | 621 | dh = dsthash_alloc_init(hinfo, &dst, &race); |
09e410de | 622 | if (dh == NULL) { |
02e4eb75 | 623 | rcu_read_unlock_bh(); |
09e410de | 624 | goto hotdrop; |
09181842 PNA |
625 | } else if (race) { |
626 | /* Already got an entry, update expiration timeout */ | |
627 | dh->expires = now + msecs_to_jiffies(hinfo->cfg.expire); | |
628 | rateinfo_recalc(dh, now, hinfo->cfg.mode); | |
629 | } else { | |
630 | dh->expires = jiffies + msecs_to_jiffies(hinfo->cfg.expire); | |
631 | rateinfo_init(dh, hinfo); | |
09e410de | 632 | } |
09e410de JE |
633 | } else { |
634 | /* update expiration timeout */ | |
635 | dh->expires = now + msecs_to_jiffies(hinfo->cfg.expire); | |
0197dee7 | 636 | rateinfo_recalc(dh, now, hinfo->cfg.mode); |
09e410de JE |
637 | } |
638 | ||
0197dee7 FW |
639 | if (info->cfg.mode & XT_HASHLIMIT_BYTES) |
640 | cost = hashlimit_byte_cost(skb->len, dh); | |
641 | else | |
642 | cost = dh->rateinfo.cost; | |
643 | ||
644 | if (dh->rateinfo.credit >= cost) { | |
09e410de | 645 | /* below the limit */ |
0197dee7 | 646 | dh->rateinfo.credit -= cost; |
02e4eb75 ED |
647 | spin_unlock(&dh->lock); |
648 | rcu_read_unlock_bh(); | |
09e410de JE |
649 | return !(info->cfg.mode & XT_HASHLIMIT_INVERT); |
650 | } | |
651 | ||
02e4eb75 ED |
652 | spin_unlock(&dh->lock); |
653 | rcu_read_unlock_bh(); | |
09e410de JE |
654 | /* default match is underlimit - so over the limit, we need to invert */ |
655 | return info->cfg.mode & XT_HASHLIMIT_INVERT; | |
656 | ||
657 | hotdrop: | |
b4ba2611 | 658 | par->hotdrop = true; |
09e410de JE |
659 | return false; |
660 | } | |
661 | ||
b0f38452 | 662 | static int hashlimit_mt_check(const struct xt_mtchk_param *par) |
09e410de | 663 | { |
e89fc3f1 | 664 | struct net *net = par->net; |
9b4fce7a | 665 | struct xt_hashlimit_mtinfo1 *info = par->matchinfo; |
4a5a5c73 | 666 | int ret; |
09e410de | 667 | |
09e410de | 668 | if (info->cfg.gc_interval == 0 || info->cfg.expire == 0) |
bd414ee6 | 669 | return -EINVAL; |
09e410de | 670 | if (info->name[sizeof(info->name)-1] != '\0') |
bd414ee6 | 671 | return -EINVAL; |
aa5fa318 | 672 | if (par->family == NFPROTO_IPV4) { |
09e410de | 673 | if (info->cfg.srcmask > 32 || info->cfg.dstmask > 32) |
bd414ee6 | 674 | return -EINVAL; |
09e410de JE |
675 | } else { |
676 | if (info->cfg.srcmask > 128 || info->cfg.dstmask > 128) | |
bd414ee6 | 677 | return -EINVAL; |
09e410de JE |
678 | } |
679 | ||
1f27e251 | 680 | if (info->cfg.mode & ~XT_HASHLIMIT_ALL) { |
0197dee7 FW |
681 | pr_info("Unknown mode mask %X, kernel too old?\n", |
682 | info->cfg.mode); | |
683 | return -EINVAL; | |
684 | } | |
685 | ||
686 | /* Check for overflow. */ | |
687 | if (info->cfg.mode & XT_HASHLIMIT_BYTES) { | |
688 | if (user2credits_byte(info->cfg.avg) == 0) { | |
689 | pr_info("overflow, rate too high: %u\n", info->cfg.avg); | |
690 | return -EINVAL; | |
691 | } | |
692 | } else if (info->cfg.burst == 0 || | |
693 | user2credits(info->cfg.avg * info->cfg.burst) < | |
694 | user2credits(info->cfg.avg)) { | |
695 | pr_info("overflow, try lower: %u/%u\n", | |
696 | info->cfg.avg, info->cfg.burst); | |
697 | return -ERANGE; | |
698 | } | |
699 | ||
2eff25c1 | 700 | mutex_lock(&hashlimit_mutex); |
aa5fa318 | 701 | info->hinfo = htable_find_get(net, info->name, par->family); |
4a5a5c73 JE |
702 | if (info->hinfo == NULL) { |
703 | ret = htable_create(net, info, par->family); | |
704 | if (ret < 0) { | |
705 | mutex_unlock(&hashlimit_mutex); | |
706 | return ret; | |
707 | } | |
09e410de | 708 | } |
2eff25c1 | 709 | mutex_unlock(&hashlimit_mutex); |
bd414ee6 | 710 | return 0; |
09e410de JE |
711 | } |
712 | ||
6be3d859 | 713 | static void hashlimit_mt_destroy(const struct xt_mtdtor_param *par) |
09e410de | 714 | { |
6be3d859 | 715 | const struct xt_hashlimit_mtinfo1 *info = par->matchinfo; |
09e410de JE |
716 | |
717 | htable_put(info->hinfo); | |
718 | } | |
719 | ||
d3c5ee6d | 720 | static struct xt_match hashlimit_mt_reg[] __read_mostly = { |
09e410de JE |
721 | { |
722 | .name = "hashlimit", | |
723 | .revision = 1, | |
ee999d8b | 724 | .family = NFPROTO_IPV4, |
09e410de JE |
725 | .match = hashlimit_mt, |
726 | .matchsize = sizeof(struct xt_hashlimit_mtinfo1), | |
727 | .checkentry = hashlimit_mt_check, | |
728 | .destroy = hashlimit_mt_destroy, | |
729 | .me = THIS_MODULE, | |
730 | }, | |
c0cd1156 | 731 | #if IS_ENABLED(CONFIG_IP6_NF_IPTABLES) |
09e410de JE |
732 | { |
733 | .name = "hashlimit", | |
734 | .revision = 1, | |
ee999d8b | 735 | .family = NFPROTO_IPV6, |
09e410de JE |
736 | .match = hashlimit_mt, |
737 | .matchsize = sizeof(struct xt_hashlimit_mtinfo1), | |
738 | .checkentry = hashlimit_mt_check, | |
739 | .destroy = hashlimit_mt_destroy, | |
740 | .me = THIS_MODULE, | |
741 | }, | |
7b21e09d | 742 | #endif |
1da177e4 LT |
743 | }; |
744 | ||
745 | /* PROC stuff */ | |
1da177e4 | 746 | static void *dl_seq_start(struct seq_file *s, loff_t *pos) |
f4f6fb71 | 747 | __acquires(htable->lock) |
1da177e4 | 748 | { |
a1004d8e | 749 | struct xt_hashlimit_htable *htable = s->private; |
1da177e4 LT |
750 | unsigned int *bucket; |
751 | ||
752 | spin_lock_bh(&htable->lock); | |
753 | if (*pos >= htable->cfg.size) | |
754 | return NULL; | |
755 | ||
756 | bucket = kmalloc(sizeof(unsigned int), GFP_ATOMIC); | |
757 | if (!bucket) | |
758 | return ERR_PTR(-ENOMEM); | |
759 | ||
760 | *bucket = *pos; | |
761 | return bucket; | |
762 | } | |
763 | ||
764 | static void *dl_seq_next(struct seq_file *s, void *v, loff_t *pos) | |
765 | { | |
a1004d8e | 766 | struct xt_hashlimit_htable *htable = s->private; |
1da177e4 LT |
767 | unsigned int *bucket = (unsigned int *)v; |
768 | ||
769 | *pos = ++(*bucket); | |
770 | if (*pos >= htable->cfg.size) { | |
771 | kfree(v); | |
772 | return NULL; | |
773 | } | |
774 | return bucket; | |
775 | } | |
776 | ||
777 | static void dl_seq_stop(struct seq_file *s, void *v) | |
f4f6fb71 | 778 | __releases(htable->lock) |
1da177e4 | 779 | { |
a1004d8e | 780 | struct xt_hashlimit_htable *htable = s->private; |
1da177e4 LT |
781 | unsigned int *bucket = (unsigned int *)v; |
782 | ||
55e0d7cf ED |
783 | if (!IS_ERR(bucket)) |
784 | kfree(bucket); | |
1da177e4 LT |
785 | spin_unlock_bh(&htable->lock); |
786 | } | |
787 | ||
76108cea | 788 | static int dl_seq_real_show(struct dsthash_ent *ent, u_int8_t family, |
39b46fc6 | 789 | struct seq_file *s) |
1da177e4 | 790 | { |
02e4eb75 | 791 | int res; |
0197dee7 | 792 | const struct xt_hashlimit_htable *ht = s->private; |
02e4eb75 ED |
793 | |
794 | spin_lock(&ent->lock); | |
1da177e4 | 795 | /* recalculate to show accurate numbers */ |
0197dee7 | 796 | rateinfo_recalc(ent, jiffies, ht->cfg.mode); |
1da177e4 | 797 | |
39b46fc6 | 798 | switch (family) { |
ee999d8b | 799 | case NFPROTO_IPV4: |
02e4eb75 | 800 | res = seq_printf(s, "%ld %pI4:%u->%pI4:%u %u %u %u\n", |
39b46fc6 | 801 | (long)(ent->expires - jiffies)/HZ, |
14d5e834 | 802 | &ent->dst.ip.src, |
39b46fc6 | 803 | ntohs(ent->dst.src_port), |
14d5e834 | 804 | &ent->dst.ip.dst, |
39b46fc6 PM |
805 | ntohs(ent->dst.dst_port), |
806 | ent->rateinfo.credit, ent->rateinfo.credit_cap, | |
807 | ent->rateinfo.cost); | |
02e4eb75 | 808 | break; |
c0cd1156 | 809 | #if IS_ENABLED(CONFIG_IP6_NF_IPTABLES) |
ee999d8b | 810 | case NFPROTO_IPV6: |
02e4eb75 | 811 | res = seq_printf(s, "%ld %pI6:%u->%pI6:%u %u %u %u\n", |
39b46fc6 | 812 | (long)(ent->expires - jiffies)/HZ, |
38ff4fa4 | 813 | &ent->dst.ip6.src, |
39b46fc6 | 814 | ntohs(ent->dst.src_port), |
38ff4fa4 | 815 | &ent->dst.ip6.dst, |
39b46fc6 PM |
816 | ntohs(ent->dst.dst_port), |
817 | ent->rateinfo.credit, ent->rateinfo.credit_cap, | |
818 | ent->rateinfo.cost); | |
02e4eb75 | 819 | break; |
7b21e09d | 820 | #endif |
39b46fc6 PM |
821 | default: |
822 | BUG(); | |
02e4eb75 | 823 | res = 0; |
39b46fc6 | 824 | } |
02e4eb75 ED |
825 | spin_unlock(&ent->lock); |
826 | return res; | |
1da177e4 LT |
827 | } |
828 | ||
829 | static int dl_seq_show(struct seq_file *s, void *v) | |
830 | { | |
a1004d8e | 831 | struct xt_hashlimit_htable *htable = s->private; |
1da177e4 LT |
832 | unsigned int *bucket = (unsigned int *)v; |
833 | struct dsthash_ent *ent; | |
1da177e4 | 834 | |
39b46fc6 | 835 | if (!hlist_empty(&htable->hash[*bucket])) { |
b67bfe0d | 836 | hlist_for_each_entry(ent, &htable->hash[*bucket], node) |
39b46fc6 | 837 | if (dl_seq_real_show(ent, htable->family, s)) |
683a04ce | 838 | return -1; |
39b46fc6 | 839 | } |
1da177e4 LT |
840 | return 0; |
841 | } | |
842 | ||
56b3d975 | 843 | static const struct seq_operations dl_seq_ops = { |
1da177e4 LT |
844 | .start = dl_seq_start, |
845 | .next = dl_seq_next, | |
846 | .stop = dl_seq_stop, | |
847 | .show = dl_seq_show | |
848 | }; | |
849 | ||
850 | static int dl_proc_open(struct inode *inode, struct file *file) | |
851 | { | |
852 | int ret = seq_open(file, &dl_seq_ops); | |
853 | ||
854 | if (!ret) { | |
855 | struct seq_file *sf = file->private_data; | |
d9dda78b | 856 | sf->private = PDE_DATA(inode); |
1da177e4 LT |
857 | } |
858 | return ret; | |
859 | } | |
860 | ||
da7071d7 | 861 | static const struct file_operations dl_file_ops = { |
1da177e4 LT |
862 | .owner = THIS_MODULE, |
863 | .open = dl_proc_open, | |
864 | .read = seq_read, | |
865 | .llseek = seq_lseek, | |
866 | .release = seq_release | |
867 | }; | |
868 | ||
e89fc3f1 AD |
869 | static int __net_init hashlimit_proc_net_init(struct net *net) |
870 | { | |
871 | struct hashlimit_net *hashlimit_net = hashlimit_pernet(net); | |
872 | ||
873 | hashlimit_net->ipt_hashlimit = proc_mkdir("ipt_hashlimit", net->proc_net); | |
874 | if (!hashlimit_net->ipt_hashlimit) | |
875 | return -ENOMEM; | |
c0cd1156 | 876 | #if IS_ENABLED(CONFIG_IP6_NF_IPTABLES) |
e89fc3f1 AD |
877 | hashlimit_net->ip6t_hashlimit = proc_mkdir("ip6t_hashlimit", net->proc_net); |
878 | if (!hashlimit_net->ip6t_hashlimit) { | |
ece31ffd | 879 | remove_proc_entry("ipt_hashlimit", net->proc_net); |
e89fc3f1 AD |
880 | return -ENOMEM; |
881 | } | |
882 | #endif | |
883 | return 0; | |
884 | } | |
885 | ||
886 | static void __net_exit hashlimit_proc_net_exit(struct net *net) | |
887 | { | |
32263dd1 | 888 | struct xt_hashlimit_htable *hinfo; |
32263dd1 VL |
889 | struct hashlimit_net *hashlimit_net = hashlimit_pernet(net); |
890 | ||
b4ef4ce0 SP |
891 | /* hashlimit_net_exit() is called before hashlimit_mt_destroy(). |
892 | * Make sure that the parent ipt_hashlimit and ip6t_hashlimit proc | |
893 | * entries is empty before trying to remove it. | |
32263dd1 VL |
894 | */ |
895 | mutex_lock(&hashlimit_mutex); | |
b67bfe0d | 896 | hlist_for_each_entry(hinfo, &hashlimit_net->htables, node) |
b4ef4ce0 | 897 | htable_remove_proc_entry(hinfo); |
32263dd1 VL |
898 | hashlimit_net->ipt_hashlimit = NULL; |
899 | hashlimit_net->ip6t_hashlimit = NULL; | |
900 | mutex_unlock(&hashlimit_mutex); | |
901 | ||
ece31ffd | 902 | remove_proc_entry("ipt_hashlimit", net->proc_net); |
c0cd1156 | 903 | #if IS_ENABLED(CONFIG_IP6_NF_IPTABLES) |
ece31ffd | 904 | remove_proc_entry("ip6t_hashlimit", net->proc_net); |
e89fc3f1 AD |
905 | #endif |
906 | } | |
907 | ||
908 | static int __net_init hashlimit_net_init(struct net *net) | |
909 | { | |
910 | struct hashlimit_net *hashlimit_net = hashlimit_pernet(net); | |
911 | ||
912 | INIT_HLIST_HEAD(&hashlimit_net->htables); | |
913 | return hashlimit_proc_net_init(net); | |
914 | } | |
915 | ||
916 | static void __net_exit hashlimit_net_exit(struct net *net) | |
917 | { | |
e89fc3f1 AD |
918 | hashlimit_proc_net_exit(net); |
919 | } | |
920 | ||
921 | static struct pernet_operations hashlimit_net_ops = { | |
922 | .init = hashlimit_net_init, | |
923 | .exit = hashlimit_net_exit, | |
924 | .id = &hashlimit_net_id, | |
925 | .size = sizeof(struct hashlimit_net), | |
926 | }; | |
927 | ||
d3c5ee6d | 928 | static int __init hashlimit_mt_init(void) |
1da177e4 | 929 | { |
39b46fc6 | 930 | int err; |
1da177e4 | 931 | |
e89fc3f1 AD |
932 | err = register_pernet_subsys(&hashlimit_net_ops); |
933 | if (err < 0) | |
934 | return err; | |
d3c5ee6d JE |
935 | err = xt_register_matches(hashlimit_mt_reg, |
936 | ARRAY_SIZE(hashlimit_mt_reg)); | |
39b46fc6 PM |
937 | if (err < 0) |
938 | goto err1; | |
1da177e4 | 939 | |
39b46fc6 PM |
940 | err = -ENOMEM; |
941 | hashlimit_cachep = kmem_cache_create("xt_hashlimit", | |
942 | sizeof(struct dsthash_ent), 0, 0, | |
20c2df83 | 943 | NULL); |
1da177e4 | 944 | if (!hashlimit_cachep) { |
8bee4bad | 945 | pr_warning("unable to create slab cache\n"); |
39b46fc6 | 946 | goto err2; |
1da177e4 | 947 | } |
e89fc3f1 AD |
948 | return 0; |
949 | ||
39b46fc6 | 950 | err2: |
d3c5ee6d | 951 | xt_unregister_matches(hashlimit_mt_reg, ARRAY_SIZE(hashlimit_mt_reg)); |
39b46fc6 | 952 | err1: |
e89fc3f1 | 953 | unregister_pernet_subsys(&hashlimit_net_ops); |
39b46fc6 | 954 | return err; |
1da177e4 | 955 | |
1da177e4 LT |
956 | } |
957 | ||
d3c5ee6d | 958 | static void __exit hashlimit_mt_exit(void) |
1da177e4 | 959 | { |
d3c5ee6d | 960 | xt_unregister_matches(hashlimit_mt_reg, ARRAY_SIZE(hashlimit_mt_reg)); |
e89fc3f1 | 961 | unregister_pernet_subsys(&hashlimit_net_ops); |
02e4eb75 ED |
962 | |
963 | rcu_barrier_bh(); | |
964 | kmem_cache_destroy(hashlimit_cachep); | |
1da177e4 LT |
965 | } |
966 | ||
d3c5ee6d JE |
967 | module_init(hashlimit_mt_init); |
968 | module_exit(hashlimit_mt_exit); |