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 | ||
39b46fc6 | 328 | static void htable_destroy(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 | ||
967ab999 | 333 | del_timer_sync(&hinfo->timer); |
1da177e4 | 334 | |
e89fc3f1 AD |
335 | if (hinfo->family == NFPROTO_IPV4) |
336 | parent = hashlimit_net->ipt_hashlimit; | |
337 | else | |
338 | parent = hashlimit_net->ip6t_hashlimit; | |
32263dd1 VL |
339 | |
340 | if(parent != NULL) | |
14b872f0 | 341 | remove_proc_entry(hinfo->name, parent); |
32263dd1 | 342 | |
1da177e4 | 343 | htable_selective_cleanup(hinfo, select_all); |
14b872f0 | 344 | kfree(hinfo->name); |
1da177e4 LT |
345 | vfree(hinfo); |
346 | } | |
347 | ||
e89fc3f1 AD |
348 | static struct xt_hashlimit_htable *htable_find_get(struct net *net, |
349 | const char *name, | |
76108cea | 350 | u_int8_t family) |
1da177e4 | 351 | { |
e89fc3f1 | 352 | struct hashlimit_net *hashlimit_net = hashlimit_pernet(net); |
39b46fc6 | 353 | struct xt_hashlimit_htable *hinfo; |
1da177e4 | 354 | |
b67bfe0d | 355 | hlist_for_each_entry(hinfo, &hashlimit_net->htables, node) { |
14b872f0 | 356 | if (!strcmp(name, hinfo->name) && |
39b46fc6 | 357 | hinfo->family == family) { |
2eff25c1 | 358 | hinfo->use++; |
1da177e4 LT |
359 | return hinfo; |
360 | } | |
361 | } | |
1da177e4 LT |
362 | return NULL; |
363 | } | |
364 | ||
39b46fc6 | 365 | static void htable_put(struct xt_hashlimit_htable *hinfo) |
1da177e4 | 366 | { |
2eff25c1 PM |
367 | mutex_lock(&hashlimit_mutex); |
368 | if (--hinfo->use == 0) { | |
1da177e4 | 369 | hlist_del(&hinfo->node); |
1da177e4 LT |
370 | htable_destroy(hinfo); |
371 | } | |
2eff25c1 | 372 | mutex_unlock(&hashlimit_mutex); |
1da177e4 LT |
373 | } |
374 | ||
1da177e4 LT |
375 | /* The algorithm used is the Simple Token Bucket Filter (TBF) |
376 | * see net/sched/sch_tbf.c in the linux source tree | |
377 | */ | |
378 | ||
379 | /* Rusty: This is my (non-mathematically-inclined) understanding of | |
380 | this algorithm. The `average rate' in jiffies becomes your initial | |
381 | amount of credit `credit' and the most credit you can ever have | |
382 | `credit_cap'. The `peak rate' becomes the cost of passing the | |
383 | test, `cost'. | |
384 | ||
385 | `prev' tracks the last packet hit: you gain one credit per jiffy. | |
386 | If you get credit balance more than this, the extra credit is | |
387 | discarded. Every time the match passes, you lose `cost' credits; | |
388 | if you don't have that many, the test fails. | |
389 | ||
390 | See Alexey's formal explanation in net/sched/sch_tbf.c. | |
391 | ||
392 | To get the maximum range, we multiply by this factor (ie. you get N | |
393 | credits per jiffy). We want to allow a rate as low as 1 per day | |
394 | (slowest userspace tool allows), which means | |
395 | CREDITS_PER_JIFFY*HZ*60*60*24 < 2^32 ie. | |
396 | */ | |
397 | #define MAX_CPJ (0xFFFFFFFF / (HZ*60*60*24)) | |
398 | ||
399 | /* Repeated shift and or gives us all 1s, final shift and add 1 gives | |
400 | * us the power of 2 below the theoretical max, so GCC simply does a | |
401 | * shift. */ | |
402 | #define _POW2_BELOW2(x) ((x)|((x)>>1)) | |
403 | #define _POW2_BELOW4(x) (_POW2_BELOW2(x)|_POW2_BELOW2((x)>>2)) | |
404 | #define _POW2_BELOW8(x) (_POW2_BELOW4(x)|_POW2_BELOW4((x)>>4)) | |
405 | #define _POW2_BELOW16(x) (_POW2_BELOW8(x)|_POW2_BELOW8((x)>>8)) | |
406 | #define _POW2_BELOW32(x) (_POW2_BELOW16(x)|_POW2_BELOW16((x)>>16)) | |
407 | #define POW2_BELOW32(x) ((_POW2_BELOW32(x)>>1) + 1) | |
408 | ||
409 | #define CREDITS_PER_JIFFY POW2_BELOW32(MAX_CPJ) | |
410 | ||
0197dee7 FW |
411 | /* in byte mode, the lowest possible rate is one packet/second. |
412 | * credit_cap is used as a counter that tells us how many times we can | |
413 | * refill the "credits available" counter when it becomes empty. | |
414 | */ | |
415 | #define MAX_CPJ_BYTES (0xFFFFFFFF / HZ) | |
416 | #define CREDITS_PER_JIFFY_BYTES POW2_BELOW32(MAX_CPJ_BYTES) | |
417 | ||
418 | static u32 xt_hashlimit_len_to_chunks(u32 len) | |
419 | { | |
420 | return (len >> XT_HASHLIMIT_BYTE_SHIFT) + 1; | |
421 | } | |
422 | ||
1da177e4 | 423 | /* Precision saver. */ |
7a909ac7 | 424 | static u32 user2credits(u32 user) |
1da177e4 LT |
425 | { |
426 | /* If multiplying would overflow... */ | |
427 | if (user > 0xFFFFFFFF / (HZ*CREDITS_PER_JIFFY)) | |
428 | /* Divide first. */ | |
39b46fc6 | 429 | return (user / XT_HASHLIMIT_SCALE) * HZ * CREDITS_PER_JIFFY; |
1da177e4 | 430 | |
39b46fc6 | 431 | return (user * HZ * CREDITS_PER_JIFFY) / XT_HASHLIMIT_SCALE; |
1da177e4 LT |
432 | } |
433 | ||
0197dee7 | 434 | static u32 user2credits_byte(u32 user) |
1da177e4 | 435 | { |
0197dee7 FW |
436 | u64 us = user; |
437 | us *= HZ * CREDITS_PER_JIFFY_BYTES; | |
438 | return (u32) (us >> 32); | |
439 | } | |
440 | ||
441 | static void rateinfo_recalc(struct dsthash_ent *dh, unsigned long now, u32 mode) | |
442 | { | |
443 | unsigned long delta = now - dh->rateinfo.prev; | |
444 | u32 cap; | |
445 | ||
446 | if (delta == 0) | |
447 | return; | |
448 | ||
39b46fc6 | 449 | dh->rateinfo.prev = now; |
0197dee7 FW |
450 | |
451 | if (mode & XT_HASHLIMIT_BYTES) { | |
452 | u32 tmp = dh->rateinfo.credit; | |
453 | dh->rateinfo.credit += CREDITS_PER_JIFFY_BYTES * delta; | |
454 | cap = CREDITS_PER_JIFFY_BYTES * HZ; | |
455 | if (tmp >= dh->rateinfo.credit) {/* overflow */ | |
456 | dh->rateinfo.credit = cap; | |
457 | return; | |
458 | } | |
459 | } else { | |
460 | dh->rateinfo.credit += delta * CREDITS_PER_JIFFY; | |
461 | cap = dh->rateinfo.credit_cap; | |
462 | } | |
463 | if (dh->rateinfo.credit > cap) | |
464 | dh->rateinfo.credit = cap; | |
39b46fc6 PM |
465 | } |
466 | ||
817e076f FW |
467 | static void rateinfo_init(struct dsthash_ent *dh, |
468 | struct xt_hashlimit_htable *hinfo) | |
469 | { | |
470 | dh->rateinfo.prev = jiffies; | |
0197dee7 FW |
471 | if (hinfo->cfg.mode & XT_HASHLIMIT_BYTES) { |
472 | dh->rateinfo.credit = CREDITS_PER_JIFFY_BYTES * HZ; | |
473 | dh->rateinfo.cost = user2credits_byte(hinfo->cfg.avg); | |
474 | dh->rateinfo.credit_cap = hinfo->cfg.burst; | |
475 | } else { | |
476 | dh->rateinfo.credit = user2credits(hinfo->cfg.avg * | |
477 | hinfo->cfg.burst); | |
478 | dh->rateinfo.cost = user2credits(hinfo->cfg.avg); | |
479 | dh->rateinfo.credit_cap = dh->rateinfo.credit; | |
480 | } | |
817e076f FW |
481 | } |
482 | ||
09e410de JE |
483 | static inline __be32 maskl(__be32 a, unsigned int l) |
484 | { | |
1b9b70ea | 485 | return l ? htonl(ntohl(a) & ~0 << (32 - l)) : 0; |
09e410de JE |
486 | } |
487 | ||
c0cd1156 | 488 | #if IS_ENABLED(CONFIG_IP6_NF_IPTABLES) |
09e410de JE |
489 | static void hashlimit_ipv6_mask(__be32 *i, unsigned int p) |
490 | { | |
491 | switch (p) { | |
1b9b70ea | 492 | case 0 ... 31: |
09e410de JE |
493 | i[0] = maskl(i[0], p); |
494 | i[1] = i[2] = i[3] = 0; | |
495 | break; | |
1b9b70ea | 496 | case 32 ... 63: |
09e410de JE |
497 | i[1] = maskl(i[1], p - 32); |
498 | i[2] = i[3] = 0; | |
499 | break; | |
1b9b70ea | 500 | case 64 ... 95: |
09e410de JE |
501 | i[2] = maskl(i[2], p - 64); |
502 | i[3] = 0; | |
8f599229 | 503 | break; |
1b9b70ea | 504 | case 96 ... 127: |
09e410de JE |
505 | i[3] = maskl(i[3], p - 96); |
506 | break; | |
507 | case 128: | |
508 | break; | |
509 | } | |
510 | } | |
3ed5df44 | 511 | #endif |
09e410de | 512 | |
39b46fc6 | 513 | static int |
a47362a2 JE |
514 | hashlimit_init_dst(const struct xt_hashlimit_htable *hinfo, |
515 | struct dsthash_dst *dst, | |
39b46fc6 PM |
516 | const struct sk_buff *skb, unsigned int protoff) |
517 | { | |
518 | __be16 _ports[2], *ports; | |
193b23c5 | 519 | u8 nexthdr; |
aca071c1 | 520 | int poff; |
39b46fc6 PM |
521 | |
522 | memset(dst, 0, sizeof(*dst)); | |
523 | ||
524 | switch (hinfo->family) { | |
ee999d8b | 525 | case NFPROTO_IPV4: |
39b46fc6 | 526 | if (hinfo->cfg.mode & XT_HASHLIMIT_HASH_DIP) |
09e410de JE |
527 | dst->ip.dst = maskl(ip_hdr(skb)->daddr, |
528 | hinfo->cfg.dstmask); | |
39b46fc6 | 529 | if (hinfo->cfg.mode & XT_HASHLIMIT_HASH_SIP) |
09e410de JE |
530 | dst->ip.src = maskl(ip_hdr(skb)->saddr, |
531 | hinfo->cfg.srcmask); | |
39b46fc6 PM |
532 | |
533 | if (!(hinfo->cfg.mode & | |
534 | (XT_HASHLIMIT_HASH_DPT | XT_HASHLIMIT_HASH_SPT))) | |
535 | return 0; | |
eddc9ec5 | 536 | nexthdr = ip_hdr(skb)->protocol; |
39b46fc6 | 537 | break; |
c0cd1156 | 538 | #if IS_ENABLED(CONFIG_IP6_NF_IPTABLES) |
ee999d8b | 539 | case NFPROTO_IPV6: |
412662d2 SR |
540 | { |
541 | __be16 frag_off; | |
542 | ||
09e410de JE |
543 | if (hinfo->cfg.mode & XT_HASHLIMIT_HASH_DIP) { |
544 | memcpy(&dst->ip6.dst, &ipv6_hdr(skb)->daddr, | |
545 | sizeof(dst->ip6.dst)); | |
546 | hashlimit_ipv6_mask(dst->ip6.dst, hinfo->cfg.dstmask); | |
547 | } | |
548 | if (hinfo->cfg.mode & XT_HASHLIMIT_HASH_SIP) { | |
549 | memcpy(&dst->ip6.src, &ipv6_hdr(skb)->saddr, | |
550 | sizeof(dst->ip6.src)); | |
551 | hashlimit_ipv6_mask(dst->ip6.src, hinfo->cfg.srcmask); | |
552 | } | |
39b46fc6 PM |
553 | |
554 | if (!(hinfo->cfg.mode & | |
555 | (XT_HASHLIMIT_HASH_DPT | XT_HASHLIMIT_HASH_SPT))) | |
556 | return 0; | |
193b23c5 | 557 | nexthdr = ipv6_hdr(skb)->nexthdr; |
75f2811c | 558 | protoff = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), &nexthdr, &frag_off); |
193b23c5 | 559 | if ((int)protoff < 0) |
39b46fc6 PM |
560 | return -1; |
561 | break; | |
412662d2 | 562 | } |
39b46fc6 PM |
563 | #endif |
564 | default: | |
565 | BUG(); | |
566 | return 0; | |
567 | } | |
568 | ||
aca071c1 CG |
569 | poff = proto_ports_offset(nexthdr); |
570 | if (poff >= 0) { | |
571 | ports = skb_header_pointer(skb, protoff + poff, sizeof(_ports), | |
39b46fc6 | 572 | &_ports); |
aca071c1 | 573 | } else { |
39b46fc6 PM |
574 | _ports[0] = _ports[1] = 0; |
575 | ports = _ports; | |
39b46fc6 PM |
576 | } |
577 | if (!ports) | |
578 | return -1; | |
579 | if (hinfo->cfg.mode & XT_HASHLIMIT_HASH_SPT) | |
580 | dst->src_port = ports[0]; | |
581 | if (hinfo->cfg.mode & XT_HASHLIMIT_HASH_DPT) | |
582 | dst->dst_port = ports[1]; | |
583 | return 0; | |
1da177e4 LT |
584 | } |
585 | ||
0197dee7 FW |
586 | static u32 hashlimit_byte_cost(unsigned int len, struct dsthash_ent *dh) |
587 | { | |
588 | u64 tmp = xt_hashlimit_len_to_chunks(len); | |
589 | tmp = tmp * dh->rateinfo.cost; | |
590 | ||
591 | if (unlikely(tmp > CREDITS_PER_JIFFY_BYTES * HZ)) | |
592 | tmp = CREDITS_PER_JIFFY_BYTES * HZ; | |
593 | ||
594 | if (dh->rateinfo.credit < tmp && dh->rateinfo.credit_cap) { | |
595 | dh->rateinfo.credit_cap--; | |
596 | dh->rateinfo.credit = CREDITS_PER_JIFFY_BYTES * HZ; | |
597 | } | |
598 | return (u32) tmp; | |
599 | } | |
600 | ||
ccb79bdc | 601 | static bool |
62fc8051 | 602 | hashlimit_mt(const struct sk_buff *skb, struct xt_action_param *par) |
09e410de | 603 | { |
f7108a20 | 604 | const struct xt_hashlimit_mtinfo1 *info = par->matchinfo; |
09e410de JE |
605 | struct xt_hashlimit_htable *hinfo = info->hinfo; |
606 | unsigned long now = jiffies; | |
607 | struct dsthash_ent *dh; | |
608 | struct dsthash_dst dst; | |
09181842 | 609 | bool race = false; |
0197dee7 | 610 | u32 cost; |
09e410de | 611 | |
f7108a20 | 612 | if (hashlimit_init_dst(hinfo, &dst, skb, par->thoff) < 0) |
09e410de JE |
613 | goto hotdrop; |
614 | ||
02e4eb75 | 615 | rcu_read_lock_bh(); |
09e410de JE |
616 | dh = dsthash_find(hinfo, &dst); |
617 | if (dh == NULL) { | |
09181842 | 618 | dh = dsthash_alloc_init(hinfo, &dst, &race); |
09e410de | 619 | if (dh == NULL) { |
02e4eb75 | 620 | rcu_read_unlock_bh(); |
09e410de | 621 | goto hotdrop; |
09181842 PNA |
622 | } else if (race) { |
623 | /* Already got an entry, update expiration timeout */ | |
624 | dh->expires = now + msecs_to_jiffies(hinfo->cfg.expire); | |
625 | rateinfo_recalc(dh, now, hinfo->cfg.mode); | |
626 | } else { | |
627 | dh->expires = jiffies + msecs_to_jiffies(hinfo->cfg.expire); | |
628 | rateinfo_init(dh, hinfo); | |
09e410de | 629 | } |
09e410de JE |
630 | } else { |
631 | /* update expiration timeout */ | |
632 | dh->expires = now + msecs_to_jiffies(hinfo->cfg.expire); | |
0197dee7 | 633 | rateinfo_recalc(dh, now, hinfo->cfg.mode); |
09e410de JE |
634 | } |
635 | ||
0197dee7 FW |
636 | if (info->cfg.mode & XT_HASHLIMIT_BYTES) |
637 | cost = hashlimit_byte_cost(skb->len, dh); | |
638 | else | |
639 | cost = dh->rateinfo.cost; | |
640 | ||
641 | if (dh->rateinfo.credit >= cost) { | |
09e410de | 642 | /* below the limit */ |
0197dee7 | 643 | dh->rateinfo.credit -= cost; |
02e4eb75 ED |
644 | spin_unlock(&dh->lock); |
645 | rcu_read_unlock_bh(); | |
09e410de JE |
646 | return !(info->cfg.mode & XT_HASHLIMIT_INVERT); |
647 | } | |
648 | ||
02e4eb75 ED |
649 | spin_unlock(&dh->lock); |
650 | rcu_read_unlock_bh(); | |
09e410de JE |
651 | /* default match is underlimit - so over the limit, we need to invert */ |
652 | return info->cfg.mode & XT_HASHLIMIT_INVERT; | |
653 | ||
654 | hotdrop: | |
b4ba2611 | 655 | par->hotdrop = true; |
09e410de JE |
656 | return false; |
657 | } | |
658 | ||
b0f38452 | 659 | static int hashlimit_mt_check(const struct xt_mtchk_param *par) |
09e410de | 660 | { |
e89fc3f1 | 661 | struct net *net = par->net; |
9b4fce7a | 662 | struct xt_hashlimit_mtinfo1 *info = par->matchinfo; |
4a5a5c73 | 663 | int ret; |
09e410de | 664 | |
09e410de | 665 | if (info->cfg.gc_interval == 0 || info->cfg.expire == 0) |
bd414ee6 | 666 | return -EINVAL; |
09e410de | 667 | if (info->name[sizeof(info->name)-1] != '\0') |
bd414ee6 | 668 | return -EINVAL; |
aa5fa318 | 669 | if (par->family == NFPROTO_IPV4) { |
09e410de | 670 | if (info->cfg.srcmask > 32 || info->cfg.dstmask > 32) |
bd414ee6 | 671 | return -EINVAL; |
09e410de JE |
672 | } else { |
673 | if (info->cfg.srcmask > 128 || info->cfg.dstmask > 128) | |
bd414ee6 | 674 | return -EINVAL; |
09e410de JE |
675 | } |
676 | ||
1f27e251 | 677 | if (info->cfg.mode & ~XT_HASHLIMIT_ALL) { |
0197dee7 FW |
678 | pr_info("Unknown mode mask %X, kernel too old?\n", |
679 | info->cfg.mode); | |
680 | return -EINVAL; | |
681 | } | |
682 | ||
683 | /* Check for overflow. */ | |
684 | if (info->cfg.mode & XT_HASHLIMIT_BYTES) { | |
685 | if (user2credits_byte(info->cfg.avg) == 0) { | |
686 | pr_info("overflow, rate too high: %u\n", info->cfg.avg); | |
687 | return -EINVAL; | |
688 | } | |
689 | } else if (info->cfg.burst == 0 || | |
690 | user2credits(info->cfg.avg * info->cfg.burst) < | |
691 | user2credits(info->cfg.avg)) { | |
692 | pr_info("overflow, try lower: %u/%u\n", | |
693 | info->cfg.avg, info->cfg.burst); | |
694 | return -ERANGE; | |
695 | } | |
696 | ||
2eff25c1 | 697 | mutex_lock(&hashlimit_mutex); |
aa5fa318 | 698 | info->hinfo = htable_find_get(net, info->name, par->family); |
4a5a5c73 JE |
699 | if (info->hinfo == NULL) { |
700 | ret = htable_create(net, info, par->family); | |
701 | if (ret < 0) { | |
702 | mutex_unlock(&hashlimit_mutex); | |
703 | return ret; | |
704 | } | |
09e410de | 705 | } |
2eff25c1 | 706 | mutex_unlock(&hashlimit_mutex); |
bd414ee6 | 707 | return 0; |
09e410de JE |
708 | } |
709 | ||
6be3d859 | 710 | static void hashlimit_mt_destroy(const struct xt_mtdtor_param *par) |
09e410de | 711 | { |
6be3d859 | 712 | const struct xt_hashlimit_mtinfo1 *info = par->matchinfo; |
09e410de JE |
713 | |
714 | htable_put(info->hinfo); | |
715 | } | |
716 | ||
d3c5ee6d | 717 | static struct xt_match hashlimit_mt_reg[] __read_mostly = { |
09e410de JE |
718 | { |
719 | .name = "hashlimit", | |
720 | .revision = 1, | |
ee999d8b | 721 | .family = NFPROTO_IPV4, |
09e410de JE |
722 | .match = hashlimit_mt, |
723 | .matchsize = sizeof(struct xt_hashlimit_mtinfo1), | |
724 | .checkentry = hashlimit_mt_check, | |
725 | .destroy = hashlimit_mt_destroy, | |
726 | .me = THIS_MODULE, | |
727 | }, | |
c0cd1156 | 728 | #if IS_ENABLED(CONFIG_IP6_NF_IPTABLES) |
09e410de JE |
729 | { |
730 | .name = "hashlimit", | |
731 | .revision = 1, | |
ee999d8b | 732 | .family = NFPROTO_IPV6, |
09e410de JE |
733 | .match = hashlimit_mt, |
734 | .matchsize = sizeof(struct xt_hashlimit_mtinfo1), | |
735 | .checkentry = hashlimit_mt_check, | |
736 | .destroy = hashlimit_mt_destroy, | |
737 | .me = THIS_MODULE, | |
738 | }, | |
7b21e09d | 739 | #endif |
1da177e4 LT |
740 | }; |
741 | ||
742 | /* PROC stuff */ | |
1da177e4 | 743 | static void *dl_seq_start(struct seq_file *s, loff_t *pos) |
f4f6fb71 | 744 | __acquires(htable->lock) |
1da177e4 | 745 | { |
a1004d8e | 746 | struct xt_hashlimit_htable *htable = s->private; |
1da177e4 LT |
747 | unsigned int *bucket; |
748 | ||
749 | spin_lock_bh(&htable->lock); | |
750 | if (*pos >= htable->cfg.size) | |
751 | return NULL; | |
752 | ||
753 | bucket = kmalloc(sizeof(unsigned int), GFP_ATOMIC); | |
754 | if (!bucket) | |
755 | return ERR_PTR(-ENOMEM); | |
756 | ||
757 | *bucket = *pos; | |
758 | return bucket; | |
759 | } | |
760 | ||
761 | static void *dl_seq_next(struct seq_file *s, void *v, loff_t *pos) | |
762 | { | |
a1004d8e | 763 | struct xt_hashlimit_htable *htable = s->private; |
1da177e4 LT |
764 | unsigned int *bucket = (unsigned int *)v; |
765 | ||
766 | *pos = ++(*bucket); | |
767 | if (*pos >= htable->cfg.size) { | |
768 | kfree(v); | |
769 | return NULL; | |
770 | } | |
771 | return bucket; | |
772 | } | |
773 | ||
774 | static void dl_seq_stop(struct seq_file *s, void *v) | |
f4f6fb71 | 775 | __releases(htable->lock) |
1da177e4 | 776 | { |
a1004d8e | 777 | struct xt_hashlimit_htable *htable = s->private; |
1da177e4 LT |
778 | unsigned int *bucket = (unsigned int *)v; |
779 | ||
55e0d7cf ED |
780 | if (!IS_ERR(bucket)) |
781 | kfree(bucket); | |
1da177e4 LT |
782 | spin_unlock_bh(&htable->lock); |
783 | } | |
784 | ||
76108cea | 785 | static int dl_seq_real_show(struct dsthash_ent *ent, u_int8_t family, |
39b46fc6 | 786 | struct seq_file *s) |
1da177e4 | 787 | { |
02e4eb75 | 788 | int res; |
0197dee7 | 789 | const struct xt_hashlimit_htable *ht = s->private; |
02e4eb75 ED |
790 | |
791 | spin_lock(&ent->lock); | |
1da177e4 | 792 | /* recalculate to show accurate numbers */ |
0197dee7 | 793 | rateinfo_recalc(ent, jiffies, ht->cfg.mode); |
1da177e4 | 794 | |
39b46fc6 | 795 | switch (family) { |
ee999d8b | 796 | case NFPROTO_IPV4: |
02e4eb75 | 797 | res = seq_printf(s, "%ld %pI4:%u->%pI4:%u %u %u %u\n", |
39b46fc6 | 798 | (long)(ent->expires - jiffies)/HZ, |
14d5e834 | 799 | &ent->dst.ip.src, |
39b46fc6 | 800 | ntohs(ent->dst.src_port), |
14d5e834 | 801 | &ent->dst.ip.dst, |
39b46fc6 PM |
802 | ntohs(ent->dst.dst_port), |
803 | ent->rateinfo.credit, ent->rateinfo.credit_cap, | |
804 | ent->rateinfo.cost); | |
02e4eb75 | 805 | break; |
c0cd1156 | 806 | #if IS_ENABLED(CONFIG_IP6_NF_IPTABLES) |
ee999d8b | 807 | case NFPROTO_IPV6: |
02e4eb75 | 808 | res = seq_printf(s, "%ld %pI6:%u->%pI6:%u %u %u %u\n", |
39b46fc6 | 809 | (long)(ent->expires - jiffies)/HZ, |
38ff4fa4 | 810 | &ent->dst.ip6.src, |
39b46fc6 | 811 | ntohs(ent->dst.src_port), |
38ff4fa4 | 812 | &ent->dst.ip6.dst, |
39b46fc6 PM |
813 | ntohs(ent->dst.dst_port), |
814 | ent->rateinfo.credit, ent->rateinfo.credit_cap, | |
815 | ent->rateinfo.cost); | |
02e4eb75 | 816 | break; |
7b21e09d | 817 | #endif |
39b46fc6 PM |
818 | default: |
819 | BUG(); | |
02e4eb75 | 820 | res = 0; |
39b46fc6 | 821 | } |
02e4eb75 ED |
822 | spin_unlock(&ent->lock); |
823 | return res; | |
1da177e4 LT |
824 | } |
825 | ||
826 | static int dl_seq_show(struct seq_file *s, void *v) | |
827 | { | |
a1004d8e | 828 | struct xt_hashlimit_htable *htable = s->private; |
1da177e4 LT |
829 | unsigned int *bucket = (unsigned int *)v; |
830 | struct dsthash_ent *ent; | |
1da177e4 | 831 | |
39b46fc6 | 832 | if (!hlist_empty(&htable->hash[*bucket])) { |
b67bfe0d | 833 | hlist_for_each_entry(ent, &htable->hash[*bucket], node) |
39b46fc6 | 834 | if (dl_seq_real_show(ent, htable->family, s)) |
683a04ce | 835 | return -1; |
39b46fc6 | 836 | } |
1da177e4 LT |
837 | return 0; |
838 | } | |
839 | ||
56b3d975 | 840 | static const struct seq_operations dl_seq_ops = { |
1da177e4 LT |
841 | .start = dl_seq_start, |
842 | .next = dl_seq_next, | |
843 | .stop = dl_seq_stop, | |
844 | .show = dl_seq_show | |
845 | }; | |
846 | ||
847 | static int dl_proc_open(struct inode *inode, struct file *file) | |
848 | { | |
849 | int ret = seq_open(file, &dl_seq_ops); | |
850 | ||
851 | if (!ret) { | |
852 | struct seq_file *sf = file->private_data; | |
d9dda78b | 853 | sf->private = PDE_DATA(inode); |
1da177e4 LT |
854 | } |
855 | return ret; | |
856 | } | |
857 | ||
da7071d7 | 858 | static const struct file_operations dl_file_ops = { |
1da177e4 LT |
859 | .owner = THIS_MODULE, |
860 | .open = dl_proc_open, | |
861 | .read = seq_read, | |
862 | .llseek = seq_lseek, | |
863 | .release = seq_release | |
864 | }; | |
865 | ||
e89fc3f1 AD |
866 | static int __net_init hashlimit_proc_net_init(struct net *net) |
867 | { | |
868 | struct hashlimit_net *hashlimit_net = hashlimit_pernet(net); | |
869 | ||
870 | hashlimit_net->ipt_hashlimit = proc_mkdir("ipt_hashlimit", net->proc_net); | |
871 | if (!hashlimit_net->ipt_hashlimit) | |
872 | return -ENOMEM; | |
c0cd1156 | 873 | #if IS_ENABLED(CONFIG_IP6_NF_IPTABLES) |
e89fc3f1 AD |
874 | hashlimit_net->ip6t_hashlimit = proc_mkdir("ip6t_hashlimit", net->proc_net); |
875 | if (!hashlimit_net->ip6t_hashlimit) { | |
ece31ffd | 876 | remove_proc_entry("ipt_hashlimit", net->proc_net); |
e89fc3f1 AD |
877 | return -ENOMEM; |
878 | } | |
879 | #endif | |
880 | return 0; | |
881 | } | |
882 | ||
883 | static void __net_exit hashlimit_proc_net_exit(struct net *net) | |
884 | { | |
32263dd1 | 885 | struct xt_hashlimit_htable *hinfo; |
32263dd1 VL |
886 | struct proc_dir_entry *pde; |
887 | struct hashlimit_net *hashlimit_net = hashlimit_pernet(net); | |
888 | ||
889 | /* recent_net_exit() is called before recent_mt_destroy(). Make sure | |
890 | * that the parent xt_recent proc entry is is empty before trying to | |
891 | * remove it. | |
892 | */ | |
893 | mutex_lock(&hashlimit_mutex); | |
894 | pde = hashlimit_net->ipt_hashlimit; | |
895 | if (pde == NULL) | |
896 | pde = hashlimit_net->ip6t_hashlimit; | |
897 | ||
b67bfe0d | 898 | hlist_for_each_entry(hinfo, &hashlimit_net->htables, node) |
14b872f0 | 899 | remove_proc_entry(hinfo->name, pde); |
32263dd1 VL |
900 | |
901 | hashlimit_net->ipt_hashlimit = NULL; | |
902 | hashlimit_net->ip6t_hashlimit = NULL; | |
903 | mutex_unlock(&hashlimit_mutex); | |
904 | ||
ece31ffd | 905 | remove_proc_entry("ipt_hashlimit", net->proc_net); |
c0cd1156 | 906 | #if IS_ENABLED(CONFIG_IP6_NF_IPTABLES) |
ece31ffd | 907 | remove_proc_entry("ip6t_hashlimit", net->proc_net); |
e89fc3f1 AD |
908 | #endif |
909 | } | |
910 | ||
911 | static int __net_init hashlimit_net_init(struct net *net) | |
912 | { | |
913 | struct hashlimit_net *hashlimit_net = hashlimit_pernet(net); | |
914 | ||
915 | INIT_HLIST_HEAD(&hashlimit_net->htables); | |
916 | return hashlimit_proc_net_init(net); | |
917 | } | |
918 | ||
919 | static void __net_exit hashlimit_net_exit(struct net *net) | |
920 | { | |
e89fc3f1 AD |
921 | hashlimit_proc_net_exit(net); |
922 | } | |
923 | ||
924 | static struct pernet_operations hashlimit_net_ops = { | |
925 | .init = hashlimit_net_init, | |
926 | .exit = hashlimit_net_exit, | |
927 | .id = &hashlimit_net_id, | |
928 | .size = sizeof(struct hashlimit_net), | |
929 | }; | |
930 | ||
d3c5ee6d | 931 | static int __init hashlimit_mt_init(void) |
1da177e4 | 932 | { |
39b46fc6 | 933 | int err; |
1da177e4 | 934 | |
e89fc3f1 AD |
935 | err = register_pernet_subsys(&hashlimit_net_ops); |
936 | if (err < 0) | |
937 | return err; | |
d3c5ee6d JE |
938 | err = xt_register_matches(hashlimit_mt_reg, |
939 | ARRAY_SIZE(hashlimit_mt_reg)); | |
39b46fc6 PM |
940 | if (err < 0) |
941 | goto err1; | |
1da177e4 | 942 | |
39b46fc6 PM |
943 | err = -ENOMEM; |
944 | hashlimit_cachep = kmem_cache_create("xt_hashlimit", | |
945 | sizeof(struct dsthash_ent), 0, 0, | |
20c2df83 | 946 | NULL); |
1da177e4 | 947 | if (!hashlimit_cachep) { |
8bee4bad | 948 | pr_warning("unable to create slab cache\n"); |
39b46fc6 | 949 | goto err2; |
1da177e4 | 950 | } |
e89fc3f1 AD |
951 | return 0; |
952 | ||
39b46fc6 | 953 | err2: |
d3c5ee6d | 954 | xt_unregister_matches(hashlimit_mt_reg, ARRAY_SIZE(hashlimit_mt_reg)); |
39b46fc6 | 955 | err1: |
e89fc3f1 | 956 | unregister_pernet_subsys(&hashlimit_net_ops); |
39b46fc6 | 957 | return err; |
1da177e4 | 958 | |
1da177e4 LT |
959 | } |
960 | ||
d3c5ee6d | 961 | static void __exit hashlimit_mt_exit(void) |
1da177e4 | 962 | { |
d3c5ee6d | 963 | xt_unregister_matches(hashlimit_mt_reg, ARRAY_SIZE(hashlimit_mt_reg)); |
e89fc3f1 | 964 | unregister_pernet_subsys(&hashlimit_net_ops); |
02e4eb75 ED |
965 | |
966 | rcu_barrier_bh(); | |
967 | kmem_cache_destroy(hashlimit_cachep); | |
1da177e4 LT |
968 | } |
969 | ||
d3c5ee6d JE |
970 | module_init(hashlimit_mt_init); |
971 | module_exit(hashlimit_mt_exit); |