blob: 7bae369603d7220171ac79f164479d39cb4e128d [file] [log] [blame]
Jan Engelhardt09e410d2008-01-31 04:48:13 -08001/*
2 * xt_hashlimit - Netfilter module to limit the number of packets per time
3 * seperately for each hashbucket (sourceip/sourceport/dstip/dstport)
Patrick McHardy39b46fc2006-11-29 02:35:36 +01004 *
Jan Engelhardt09e410d2008-01-31 04:48:13 -08005 * (C) 2003-2004 by Harald Welte <laforge@netfilter.org>
6 * Copyright © CC Computer Consultants GmbH, 2007 - 2008
Patrick McHardy39b46fc2006-11-29 02:35:36 +01007 *
8 * Development of this code was funded by Astaro AG, http://www.astaro.com/
9 */
10#include <linux/module.h>
11#include <linux/spinlock.h>
12#include <linux/random.h>
13#include <linux/jhash.h>
14#include <linux/slab.h>
15#include <linux/vmalloc.h>
16#include <linux/proc_fs.h>
17#include <linux/seq_file.h>
18#include <linux/list.h>
19#include <linux/skbuff.h>
Al Virod7fe0f22006-12-03 23:15:30 -050020#include <linux/mm.h>
Patrick McHardy39b46fc2006-11-29 02:35:36 +010021#include <linux/in.h>
22#include <linux/ip.h>
Eric Dumazet7b21e092007-12-17 22:45:28 -080023#if defined(CONFIG_IP6_NF_IPTABLES) || defined(CONFIG_IP6_NF_IPTABLES_MODULE)
Patrick McHardy39b46fc2006-11-29 02:35:36 +010024#include <linux/ipv6.h>
Patrick McHardy193b23c2007-12-04 23:51:48 -080025#include <net/ipv6.h>
Eric Dumazet7b21e092007-12-17 22:45:28 -080026#endif
27
Eric W. Biederman457c4cb2007-09-12 12:01:34 +020028#include <net/net_namespace.h>
Patrick McHardy39b46fc2006-11-29 02:35:36 +010029
30#include <linux/netfilter/x_tables.h>
31#include <linux/netfilter_ipv4/ip_tables.h>
32#include <linux/netfilter_ipv6/ip6_tables.h>
33#include <linux/netfilter/xt_hashlimit.h>
34#include <linux/mutex.h>
35
36MODULE_LICENSE("GPL");
37MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");
Jan Engelhardt09e410d2008-01-31 04:48:13 -080038MODULE_AUTHOR("Jan Engelhardt <jengelh@computergmbh.de>");
Jan Engelhardt2ae15b62008-01-14 23:42:28 -080039MODULE_DESCRIPTION("Xtables: per hash-bucket rate-limit match");
Patrick McHardy39b46fc2006-11-29 02:35:36 +010040MODULE_ALIAS("ipt_hashlimit");
41MODULE_ALIAS("ip6t_hashlimit");
42
43/* need to declare this at the top */
44static struct proc_dir_entry *hashlimit_procdir4;
45static struct proc_dir_entry *hashlimit_procdir6;
Arjan van de Venda7071d2007-02-12 00:55:36 -080046static const struct file_operations dl_file_ops;
Patrick McHardy39b46fc2006-11-29 02:35:36 +010047
48/* hash table crap */
49struct dsthash_dst {
50 union {
51 struct {
52 __be32 src;
53 __be32 dst;
54 } ip;
Eric Dumazet7b21e092007-12-17 22:45:28 -080055#if defined(CONFIG_IP6_NF_IPTABLES) || defined(CONFIG_IP6_NF_IPTABLES_MODULE)
Patrick McHardy39b46fc2006-11-29 02:35:36 +010056 struct {
57 __be32 src[4];
58 __be32 dst[4];
59 } ip6;
Eric Dumazet7b21e092007-12-17 22:45:28 -080060#endif
Jan Engelhardt09e410d2008-01-31 04:48:13 -080061 };
Patrick McHardy39b46fc2006-11-29 02:35:36 +010062 __be16 src_port;
63 __be16 dst_port;
64};
65
66struct dsthash_ent {
67 /* static / read-only parts in the beginning */
68 struct hlist_node node;
69 struct dsthash_dst dst;
70
71 /* modified structure members in the end */
72 unsigned long expires; /* precalculated expiry time */
73 struct {
74 unsigned long prev; /* last modification */
75 u_int32_t credit;
76 u_int32_t credit_cap, cost;
77 } rateinfo;
78};
79
80struct xt_hashlimit_htable {
81 struct hlist_node node; /* global list of all htables */
82 atomic_t use;
Jan Engelhardt76108ce2008-10-08 11:35:00 +020083 u_int8_t family;
Patrick McHardy39b46fc2006-11-29 02:35:36 +010084
Jan Engelhardt09e410d2008-01-31 04:48:13 -080085 struct hashlimit_cfg1 cfg; /* config */
Patrick McHardy39b46fc2006-11-29 02:35:36 +010086
87 /* used internally */
88 spinlock_t lock; /* lock for list_head */
89 u_int32_t rnd; /* random seed for hash */
90 int rnd_initialized;
91 unsigned int count; /* number entries in table */
92 struct timer_list timer; /* timer for gc */
93
94 /* seq_file stuff */
95 struct proc_dir_entry *pde;
96
97 struct hlist_head hash[0]; /* hashtable itself */
98};
99
100static DEFINE_SPINLOCK(hashlimit_lock); /* protects htables list */
101static DEFINE_MUTEX(hlimit_mutex); /* additional checkentry protection */
102static HLIST_HEAD(hashlimit_htables);
Christoph Lametere18b8902006-12-06 20:33:20 -0800103static struct kmem_cache *hashlimit_cachep __read_mostly;
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100104
Jan Engelhardt1d93a9c2007-07-07 22:15:35 -0700105static inline bool dst_cmp(const struct dsthash_ent *ent,
Jan Engelhardta47362a2007-07-07 22:16:55 -0700106 const struct dsthash_dst *b)
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100107{
108 return !memcmp(&ent->dst, b, sizeof(ent->dst));
109}
110
111static u_int32_t
112hash_dst(const struct xt_hashlimit_htable *ht, const struct dsthash_dst *dst)
113{
Eric Dumazete2f82ac2007-12-17 22:45:13 -0800114 u_int32_t hash = jhash2((const u32 *)dst,
115 sizeof(*dst)/sizeof(u32),
116 ht->rnd);
117 /*
118 * Instead of returning hash % ht->cfg.size (implying a divide)
119 * we return the high 32 bits of the (hash * ht->cfg.size) that will
120 * give results between [0 and cfg.size-1] and same hash distribution,
121 * but using a multiply, less expensive than a divide
122 */
123 return ((u64)hash * ht->cfg.size) >> 32;
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100124}
125
126static struct dsthash_ent *
Jan Engelhardta47362a2007-07-07 22:16:55 -0700127dsthash_find(const struct xt_hashlimit_htable *ht,
128 const struct dsthash_dst *dst)
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100129{
130 struct dsthash_ent *ent;
131 struct hlist_node *pos;
132 u_int32_t hash = hash_dst(ht, dst);
133
134 if (!hlist_empty(&ht->hash[hash])) {
135 hlist_for_each_entry(ent, pos, &ht->hash[hash], node)
136 if (dst_cmp(ent, dst))
137 return ent;
138 }
139 return NULL;
140}
141
142/* allocate dsthash_ent, initialize dst, put in htable and lock it */
143static struct dsthash_ent *
Jan Engelhardta47362a2007-07-07 22:16:55 -0700144dsthash_alloc_init(struct xt_hashlimit_htable *ht,
145 const struct dsthash_dst *dst)
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100146{
147 struct dsthash_ent *ent;
148
149 /* initialize hash with random val at the time we allocate
150 * the first hashtable entry */
151 if (!ht->rnd_initialized) {
152 get_random_bytes(&ht->rnd, 4);
153 ht->rnd_initialized = 1;
154 }
155
156 if (ht->cfg.max && ht->count >= ht->cfg.max) {
157 /* FIXME: do something. question is what.. */
158 if (net_ratelimit())
159 printk(KERN_WARNING
160 "xt_hashlimit: max count of %u reached\n",
161 ht->cfg.max);
162 return NULL;
163 }
164
165 ent = kmem_cache_alloc(hashlimit_cachep, GFP_ATOMIC);
166 if (!ent) {
167 if (net_ratelimit())
168 printk(KERN_ERR
169 "xt_hashlimit: can't allocate dsthash_ent\n");
170 return NULL;
171 }
172 memcpy(&ent->dst, dst, sizeof(ent->dst));
173
174 hlist_add_head(&ent->node, &ht->hash[hash_dst(ht, dst)]);
175 ht->count++;
176 return ent;
177}
178
179static inline void
180dsthash_free(struct xt_hashlimit_htable *ht, struct dsthash_ent *ent)
181{
182 hlist_del(&ent->node);
183 kmem_cache_free(hashlimit_cachep, ent);
184 ht->count--;
185}
186static void htable_gc(unsigned long htlong);
187
Jan Engelhardt76108ce2008-10-08 11:35:00 +0200188static int htable_create_v0(struct xt_hashlimit_info *minfo, u_int8_t family)
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100189{
190 struct xt_hashlimit_htable *hinfo;
191 unsigned int size;
192 unsigned int i;
193
194 if (minfo->cfg.size)
195 size = minfo->cfg.size;
196 else {
197 size = ((num_physpages << PAGE_SHIFT) / 16384) /
198 sizeof(struct list_head);
199 if (num_physpages > (1024 * 1024 * 1024 / PAGE_SIZE))
200 size = 8192;
201 if (size < 16)
202 size = 16;
203 }
204 /* FIXME: don't use vmalloc() here or anywhere else -HW */
205 hinfo = vmalloc(sizeof(struct xt_hashlimit_htable) +
206 sizeof(struct list_head) * size);
207 if (!hinfo) {
208 printk(KERN_ERR "xt_hashlimit: unable to create hashtable\n");
209 return -1;
210 }
211 minfo->hinfo = hinfo;
212
213 /* copy match config into hashtable config */
Jan Engelhardt09e410d2008-01-31 04:48:13 -0800214 hinfo->cfg.mode = minfo->cfg.mode;
215 hinfo->cfg.avg = minfo->cfg.avg;
216 hinfo->cfg.burst = minfo->cfg.burst;
217 hinfo->cfg.max = minfo->cfg.max;
218 hinfo->cfg.gc_interval = minfo->cfg.gc_interval;
219 hinfo->cfg.expire = minfo->cfg.expire;
220
Jan Engelhardtee999d82008-10-08 11:35:01 +0200221 if (family == NFPROTO_IPV4)
Jan Engelhardt09e410d2008-01-31 04:48:13 -0800222 hinfo->cfg.srcmask = hinfo->cfg.dstmask = 32;
223 else
224 hinfo->cfg.srcmask = hinfo->cfg.dstmask = 128;
225
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100226 hinfo->cfg.size = size;
227 if (!hinfo->cfg.max)
228 hinfo->cfg.max = 8 * hinfo->cfg.size;
229 else if (hinfo->cfg.max < hinfo->cfg.size)
230 hinfo->cfg.max = hinfo->cfg.size;
231
232 for (i = 0; i < hinfo->cfg.size; i++)
233 INIT_HLIST_HEAD(&hinfo->hash[i]);
234
235 atomic_set(&hinfo->use, 1);
236 hinfo->count = 0;
237 hinfo->family = family;
238 hinfo->rnd_initialized = 0;
239 spin_lock_init(&hinfo->lock);
Jan Engelhardtee999d82008-10-08 11:35:01 +0200240 hinfo->pde = proc_create_data(minfo->name, 0,
241 (family == NFPROTO_IPV4) ?
242 hashlimit_procdir4 : hashlimit_procdir6,
243 &dl_file_ops, hinfo);
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100244 if (!hinfo->pde) {
245 vfree(hinfo);
246 return -1;
247 }
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100248
Patrick McHardye6f689d2007-03-23 11:16:30 -0700249 setup_timer(&hinfo->timer, htable_gc, (unsigned long )hinfo);
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100250 hinfo->timer.expires = jiffies + msecs_to_jiffies(hinfo->cfg.gc_interval);
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100251 add_timer(&hinfo->timer);
252
253 spin_lock_bh(&hashlimit_lock);
254 hlist_add_head(&hinfo->node, &hashlimit_htables);
255 spin_unlock_bh(&hashlimit_lock);
256
257 return 0;
258}
259
Jan Engelhardt76108ce2008-10-08 11:35:00 +0200260static int htable_create(struct xt_hashlimit_mtinfo1 *minfo, u_int8_t family)
Jan Engelhardt09e410d2008-01-31 04:48:13 -0800261{
262 struct xt_hashlimit_htable *hinfo;
263 unsigned int size;
264 unsigned int i;
265
266 if (minfo->cfg.size) {
267 size = minfo->cfg.size;
268 } else {
269 size = (num_physpages << PAGE_SHIFT) / 16384 /
270 sizeof(struct list_head);
271 if (num_physpages > 1024 * 1024 * 1024 / PAGE_SIZE)
272 size = 8192;
273 if (size < 16)
274 size = 16;
275 }
276 /* FIXME: don't use vmalloc() here or anywhere else -HW */
277 hinfo = vmalloc(sizeof(struct xt_hashlimit_htable) +
278 sizeof(struct list_head) * size);
279 if (hinfo == NULL) {
280 printk(KERN_ERR "xt_hashlimit: unable to create hashtable\n");
281 return -1;
282 }
283 minfo->hinfo = hinfo;
284
285 /* copy match config into hashtable config */
286 memcpy(&hinfo->cfg, &minfo->cfg, sizeof(hinfo->cfg));
287 hinfo->cfg.size = size;
288 if (hinfo->cfg.max == 0)
289 hinfo->cfg.max = 8 * hinfo->cfg.size;
290 else if (hinfo->cfg.max < hinfo->cfg.size)
291 hinfo->cfg.max = hinfo->cfg.size;
292
293 for (i = 0; i < hinfo->cfg.size; i++)
294 INIT_HLIST_HEAD(&hinfo->hash[i]);
295
296 atomic_set(&hinfo->use, 1);
297 hinfo->count = 0;
298 hinfo->family = family;
299 hinfo->rnd_initialized = 0;
300 spin_lock_init(&hinfo->lock);
301
Jan Engelhardtee999d82008-10-08 11:35:01 +0200302 hinfo->pde = proc_create_data(minfo->name, 0,
303 (family == NFPROTO_IPV4) ?
304 hashlimit_procdir4 : hashlimit_procdir6,
305 &dl_file_ops, hinfo);
Jan Engelhardt09e410d2008-01-31 04:48:13 -0800306 if (hinfo->pde == NULL) {
307 vfree(hinfo);
308 return -1;
309 }
Jan Engelhardt09e410d2008-01-31 04:48:13 -0800310
311 setup_timer(&hinfo->timer, htable_gc, (unsigned long)hinfo);
312 hinfo->timer.expires = jiffies + msecs_to_jiffies(hinfo->cfg.gc_interval);
313 add_timer(&hinfo->timer);
314
315 spin_lock_bh(&hashlimit_lock);
316 hlist_add_head(&hinfo->node, &hashlimit_htables);
317 spin_unlock_bh(&hashlimit_lock);
318
319 return 0;
320}
321
Jan Engelhardta47362a2007-07-07 22:16:55 -0700322static bool select_all(const struct xt_hashlimit_htable *ht,
323 const struct dsthash_ent *he)
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100324{
325 return 1;
326}
327
Jan Engelhardta47362a2007-07-07 22:16:55 -0700328static bool select_gc(const struct xt_hashlimit_htable *ht,
329 const struct dsthash_ent *he)
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100330{
Eric Dumazetcbebc512007-12-12 11:11:28 -0800331 return time_after_eq(jiffies, he->expires);
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100332}
333
334static void htable_selective_cleanup(struct xt_hashlimit_htable *ht,
Jan Engelhardta47362a2007-07-07 22:16:55 -0700335 bool (*select)(const struct xt_hashlimit_htable *ht,
336 const struct dsthash_ent *he))
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100337{
338 unsigned int i;
339
340 /* lock hash table and iterate over it */
341 spin_lock_bh(&ht->lock);
342 for (i = 0; i < ht->cfg.size; i++) {
343 struct dsthash_ent *dh;
344 struct hlist_node *pos, *n;
345 hlist_for_each_entry_safe(dh, pos, n, &ht->hash[i], node) {
346 if ((*select)(ht, dh))
347 dsthash_free(ht, dh);
348 }
349 }
350 spin_unlock_bh(&ht->lock);
351}
352
353/* hash table garbage collector, run by timer */
354static void htable_gc(unsigned long htlong)
355{
356 struct xt_hashlimit_htable *ht = (struct xt_hashlimit_htable *)htlong;
357
358 htable_selective_cleanup(ht, select_gc);
359
360 /* re-add the timer accordingly */
361 ht->timer.expires = jiffies + msecs_to_jiffies(ht->cfg.gc_interval);
362 add_timer(&ht->timer);
363}
364
365static void htable_destroy(struct xt_hashlimit_htable *hinfo)
366{
Pavel Emelyanov967ab992008-07-31 00:38:52 -0700367 del_timer_sync(&hinfo->timer);
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100368
369 /* remove proc entry */
370 remove_proc_entry(hinfo->pde->name,
Jan Engelhardtee999d82008-10-08 11:35:01 +0200371 hinfo->family == NFPROTO_IPV4 ? hashlimit_procdir4 :
YOSHIFUJI Hideaki601e68e2007-02-12 11:15:49 -0800372 hashlimit_procdir6);
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100373 htable_selective_cleanup(hinfo, select_all);
374 vfree(hinfo);
375}
376
Jan Engelhardta47362a2007-07-07 22:16:55 -0700377static struct xt_hashlimit_htable *htable_find_get(const char *name,
Jan Engelhardt76108ce2008-10-08 11:35:00 +0200378 u_int8_t family)
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100379{
380 struct xt_hashlimit_htable *hinfo;
381 struct hlist_node *pos;
382
383 spin_lock_bh(&hashlimit_lock);
384 hlist_for_each_entry(hinfo, pos, &hashlimit_htables, node) {
385 if (!strcmp(name, hinfo->pde->name) &&
386 hinfo->family == family) {
387 atomic_inc(&hinfo->use);
388 spin_unlock_bh(&hashlimit_lock);
389 return hinfo;
390 }
391 }
392 spin_unlock_bh(&hashlimit_lock);
393 return NULL;
394}
395
396static void htable_put(struct xt_hashlimit_htable *hinfo)
397{
398 if (atomic_dec_and_test(&hinfo->use)) {
399 spin_lock_bh(&hashlimit_lock);
400 hlist_del(&hinfo->node);
401 spin_unlock_bh(&hashlimit_lock);
402 htable_destroy(hinfo);
403 }
404}
405
406/* The algorithm used is the Simple Token Bucket Filter (TBF)
407 * see net/sched/sch_tbf.c in the linux source tree
408 */
409
410/* Rusty: This is my (non-mathematically-inclined) understanding of
411 this algorithm. The `average rate' in jiffies becomes your initial
412 amount of credit `credit' and the most credit you can ever have
413 `credit_cap'. The `peak rate' becomes the cost of passing the
414 test, `cost'.
415
416 `prev' tracks the last packet hit: you gain one credit per jiffy.
417 If you get credit balance more than this, the extra credit is
418 discarded. Every time the match passes, you lose `cost' credits;
419 if you don't have that many, the test fails.
420
421 See Alexey's formal explanation in net/sched/sch_tbf.c.
422
423 To get the maximum range, we multiply by this factor (ie. you get N
424 credits per jiffy). We want to allow a rate as low as 1 per day
425 (slowest userspace tool allows), which means
426 CREDITS_PER_JIFFY*HZ*60*60*24 < 2^32 ie.
427*/
428#define MAX_CPJ (0xFFFFFFFF / (HZ*60*60*24))
429
430/* Repeated shift and or gives us all 1s, final shift and add 1 gives
431 * us the power of 2 below the theoretical max, so GCC simply does a
432 * shift. */
433#define _POW2_BELOW2(x) ((x)|((x)>>1))
434#define _POW2_BELOW4(x) (_POW2_BELOW2(x)|_POW2_BELOW2((x)>>2))
435#define _POW2_BELOW8(x) (_POW2_BELOW4(x)|_POW2_BELOW4((x)>>4))
436#define _POW2_BELOW16(x) (_POW2_BELOW8(x)|_POW2_BELOW8((x)>>8))
437#define _POW2_BELOW32(x) (_POW2_BELOW16(x)|_POW2_BELOW16((x)>>16))
438#define POW2_BELOW32(x) ((_POW2_BELOW32(x)>>1) + 1)
439
440#define CREDITS_PER_JIFFY POW2_BELOW32(MAX_CPJ)
441
442/* Precision saver. */
443static inline u_int32_t
444user2credits(u_int32_t user)
445{
446 /* If multiplying would overflow... */
447 if (user > 0xFFFFFFFF / (HZ*CREDITS_PER_JIFFY))
448 /* Divide first. */
449 return (user / XT_HASHLIMIT_SCALE) * HZ * CREDITS_PER_JIFFY;
450
451 return (user * HZ * CREDITS_PER_JIFFY) / XT_HASHLIMIT_SCALE;
452}
453
454static inline void rateinfo_recalc(struct dsthash_ent *dh, unsigned long now)
455{
456 dh->rateinfo.credit += (now - dh->rateinfo.prev) * CREDITS_PER_JIFFY;
457 if (dh->rateinfo.credit > dh->rateinfo.credit_cap)
458 dh->rateinfo.credit = dh->rateinfo.credit_cap;
459 dh->rateinfo.prev = now;
460}
461
Jan Engelhardt09e410d2008-01-31 04:48:13 -0800462static inline __be32 maskl(__be32 a, unsigned int l)
463{
Patrick McHardy1b9b70e2008-04-09 15:14:18 -0700464 return l ? htonl(ntohl(a) & ~0 << (32 - l)) : 0;
Jan Engelhardt09e410d2008-01-31 04:48:13 -0800465}
466
Pavel Emelyanov3ed5df42008-01-31 18:42:26 -0800467#if defined(CONFIG_IP6_NF_IPTABLES) || defined(CONFIG_IP6_NF_IPTABLES_MODULE)
Jan Engelhardt09e410d2008-01-31 04:48:13 -0800468static void hashlimit_ipv6_mask(__be32 *i, unsigned int p)
469{
470 switch (p) {
Patrick McHardy1b9b70e2008-04-09 15:14:18 -0700471 case 0 ... 31:
Jan Engelhardt09e410d2008-01-31 04:48:13 -0800472 i[0] = maskl(i[0], p);
473 i[1] = i[2] = i[3] = 0;
474 break;
Patrick McHardy1b9b70e2008-04-09 15:14:18 -0700475 case 32 ... 63:
Jan Engelhardt09e410d2008-01-31 04:48:13 -0800476 i[1] = maskl(i[1], p - 32);
477 i[2] = i[3] = 0;
478 break;
Patrick McHardy1b9b70e2008-04-09 15:14:18 -0700479 case 64 ... 95:
Jan Engelhardt09e410d2008-01-31 04:48:13 -0800480 i[2] = maskl(i[2], p - 64);
481 i[3] = 0;
Patrick McHardy1b9b70e2008-04-09 15:14:18 -0700482 case 96 ... 127:
Jan Engelhardt09e410d2008-01-31 04:48:13 -0800483 i[3] = maskl(i[3], p - 96);
484 break;
485 case 128:
486 break;
487 }
488}
Pavel Emelyanov3ed5df42008-01-31 18:42:26 -0800489#endif
Jan Engelhardt09e410d2008-01-31 04:48:13 -0800490
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100491static int
Jan Engelhardta47362a2007-07-07 22:16:55 -0700492hashlimit_init_dst(const struct xt_hashlimit_htable *hinfo,
493 struct dsthash_dst *dst,
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100494 const struct sk_buff *skb, unsigned int protoff)
495{
496 __be16 _ports[2], *ports;
Patrick McHardy193b23c2007-12-04 23:51:48 -0800497 u8 nexthdr;
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100498
499 memset(dst, 0, sizeof(*dst));
500
501 switch (hinfo->family) {
Jan Engelhardtee999d82008-10-08 11:35:01 +0200502 case NFPROTO_IPV4:
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100503 if (hinfo->cfg.mode & XT_HASHLIMIT_HASH_DIP)
Jan Engelhardt09e410d2008-01-31 04:48:13 -0800504 dst->ip.dst = maskl(ip_hdr(skb)->daddr,
505 hinfo->cfg.dstmask);
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100506 if (hinfo->cfg.mode & XT_HASHLIMIT_HASH_SIP)
Jan Engelhardt09e410d2008-01-31 04:48:13 -0800507 dst->ip.src = maskl(ip_hdr(skb)->saddr,
508 hinfo->cfg.srcmask);
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100509
510 if (!(hinfo->cfg.mode &
511 (XT_HASHLIMIT_HASH_DPT | XT_HASHLIMIT_HASH_SPT)))
512 return 0;
Arnaldo Carvalho de Meloeddc9ec2007-04-20 22:47:35 -0700513 nexthdr = ip_hdr(skb)->protocol;
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100514 break;
Yasuyuki Kozakai02dba022006-12-02 22:19:01 -0800515#if defined(CONFIG_IP6_NF_IPTABLES) || defined(CONFIG_IP6_NF_IPTABLES_MODULE)
Jan Engelhardtee999d82008-10-08 11:35:01 +0200516 case NFPROTO_IPV6:
Jan Engelhardt09e410d2008-01-31 04:48:13 -0800517 if (hinfo->cfg.mode & XT_HASHLIMIT_HASH_DIP) {
518 memcpy(&dst->ip6.dst, &ipv6_hdr(skb)->daddr,
519 sizeof(dst->ip6.dst));
520 hashlimit_ipv6_mask(dst->ip6.dst, hinfo->cfg.dstmask);
521 }
522 if (hinfo->cfg.mode & XT_HASHLIMIT_HASH_SIP) {
523 memcpy(&dst->ip6.src, &ipv6_hdr(skb)->saddr,
524 sizeof(dst->ip6.src));
525 hashlimit_ipv6_mask(dst->ip6.src, hinfo->cfg.srcmask);
526 }
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100527
528 if (!(hinfo->cfg.mode &
529 (XT_HASHLIMIT_HASH_DPT | XT_HASHLIMIT_HASH_SPT)))
530 return 0;
Patrick McHardy193b23c2007-12-04 23:51:48 -0800531 nexthdr = ipv6_hdr(skb)->nexthdr;
532 protoff = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), &nexthdr);
533 if ((int)protoff < 0)
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100534 return -1;
535 break;
536#endif
537 default:
538 BUG();
539 return 0;
540 }
541
542 switch (nexthdr) {
543 case IPPROTO_TCP:
544 case IPPROTO_UDP:
Patrick McHardya8d0f952007-02-07 15:07:43 -0800545 case IPPROTO_UDPLITE:
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100546 case IPPROTO_SCTP:
547 case IPPROTO_DCCP:
548 ports = skb_header_pointer(skb, protoff, sizeof(_ports),
549 &_ports);
550 break;
551 default:
552 _ports[0] = _ports[1] = 0;
553 ports = _ports;
554 break;
555 }
556 if (!ports)
557 return -1;
558 if (hinfo->cfg.mode & XT_HASHLIMIT_HASH_SPT)
559 dst->src_port = ports[0];
560 if (hinfo->cfg.mode & XT_HASHLIMIT_HASH_DPT)
561 dst->dst_port = ports[1];
562 return 0;
563}
564
Jan Engelhardt1d93a9c2007-07-07 22:15:35 -0700565static bool
Jan Engelhardt09e410d2008-01-31 04:48:13 -0800566hashlimit_mt_v0(const struct sk_buff *skb, const struct net_device *in,
567 const struct net_device *out, const struct xt_match *match,
568 const void *matchinfo, int offset, unsigned int protoff,
569 bool *hotdrop)
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100570{
Jan Engelhardta47362a2007-07-07 22:16:55 -0700571 const struct xt_hashlimit_info *r =
572 ((const struct xt_hashlimit_info *)matchinfo)->u.master;
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100573 struct xt_hashlimit_htable *hinfo = r->hinfo;
574 unsigned long now = jiffies;
575 struct dsthash_ent *dh;
576 struct dsthash_dst dst;
577
578 if (hashlimit_init_dst(hinfo, &dst, skb, protoff) < 0)
579 goto hotdrop;
580
581 spin_lock_bh(&hinfo->lock);
582 dh = dsthash_find(hinfo, &dst);
583 if (!dh) {
584 dh = dsthash_alloc_init(hinfo, &dst);
585 if (!dh) {
586 spin_unlock_bh(&hinfo->lock);
587 goto hotdrop;
588 }
589
590 dh->expires = jiffies + msecs_to_jiffies(hinfo->cfg.expire);
591 dh->rateinfo.prev = jiffies;
592 dh->rateinfo.credit = user2credits(hinfo->cfg.avg *
593 hinfo->cfg.burst);
594 dh->rateinfo.credit_cap = user2credits(hinfo->cfg.avg *
595 hinfo->cfg.burst);
596 dh->rateinfo.cost = user2credits(hinfo->cfg.avg);
597 } else {
598 /* update expiration timeout */
599 dh->expires = now + msecs_to_jiffies(hinfo->cfg.expire);
600 rateinfo_recalc(dh, now);
601 }
602
603 if (dh->rateinfo.credit >= dh->rateinfo.cost) {
604 /* We're underlimit. */
605 dh->rateinfo.credit -= dh->rateinfo.cost;
606 spin_unlock_bh(&hinfo->lock);
Jan Engelhardt1d93a9c2007-07-07 22:15:35 -0700607 return true;
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100608 }
609
YOSHIFUJI Hideaki601e68e2007-02-12 11:15:49 -0800610 spin_unlock_bh(&hinfo->lock);
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100611
612 /* default case: we're overlimit, thus don't match */
Jan Engelhardt1d93a9c2007-07-07 22:15:35 -0700613 return false;
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100614
615hotdrop:
Jan Engelhardtcff533a2007-07-07 22:15:12 -0700616 *hotdrop = true;
Jan Engelhardt1d93a9c2007-07-07 22:15:35 -0700617 return false;
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100618}
619
Jan Engelhardtccb79bd2007-07-07 22:16:00 -0700620static bool
Jan Engelhardt09e410d2008-01-31 04:48:13 -0800621hashlimit_mt(const struct sk_buff *skb, const struct net_device *in,
622 const struct net_device *out, const struct xt_match *match,
623 const void *matchinfo, int offset, unsigned int protoff,
624 bool *hotdrop)
625{
626 const struct xt_hashlimit_mtinfo1 *info = matchinfo;
627 struct xt_hashlimit_htable *hinfo = info->hinfo;
628 unsigned long now = jiffies;
629 struct dsthash_ent *dh;
630 struct dsthash_dst dst;
631
632 if (hashlimit_init_dst(hinfo, &dst, skb, protoff) < 0)
633 goto hotdrop;
634
635 spin_lock_bh(&hinfo->lock);
636 dh = dsthash_find(hinfo, &dst);
637 if (dh == NULL) {
638 dh = dsthash_alloc_init(hinfo, &dst);
639 if (dh == NULL) {
640 spin_unlock_bh(&hinfo->lock);
641 goto hotdrop;
642 }
643
644 dh->expires = jiffies + msecs_to_jiffies(hinfo->cfg.expire);
645 dh->rateinfo.prev = jiffies;
646 dh->rateinfo.credit = user2credits(hinfo->cfg.avg *
647 hinfo->cfg.burst);
648 dh->rateinfo.credit_cap = user2credits(hinfo->cfg.avg *
649 hinfo->cfg.burst);
650 dh->rateinfo.cost = user2credits(hinfo->cfg.avg);
651 } else {
652 /* update expiration timeout */
653 dh->expires = now + msecs_to_jiffies(hinfo->cfg.expire);
654 rateinfo_recalc(dh, now);
655 }
656
657 if (dh->rateinfo.credit >= dh->rateinfo.cost) {
658 /* below the limit */
659 dh->rateinfo.credit -= dh->rateinfo.cost;
660 spin_unlock_bh(&hinfo->lock);
661 return !(info->cfg.mode & XT_HASHLIMIT_INVERT);
662 }
663
664 spin_unlock_bh(&hinfo->lock);
665 /* default match is underlimit - so over the limit, we need to invert */
666 return info->cfg.mode & XT_HASHLIMIT_INVERT;
667
668 hotdrop:
669 *hotdrop = true;
670 return false;
671}
672
673static bool
674hashlimit_mt_check_v0(const char *tablename, const void *inf,
675 const struct xt_match *match, void *matchinfo,
676 unsigned int hook_mask)
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100677{
678 struct xt_hashlimit_info *r = matchinfo;
679
680 /* Check for overflow. */
681 if (r->cfg.burst == 0 ||
682 user2credits(r->cfg.avg * r->cfg.burst) < user2credits(r->cfg.avg)) {
683 printk(KERN_ERR "xt_hashlimit: overflow, try lower: %u/%u\n",
684 r->cfg.avg, r->cfg.burst);
Jan Engelhardtccb79bd2007-07-07 22:16:00 -0700685 return false;
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100686 }
687 if (r->cfg.mode == 0 ||
688 r->cfg.mode > (XT_HASHLIMIT_HASH_DPT |
689 XT_HASHLIMIT_HASH_DIP |
690 XT_HASHLIMIT_HASH_SIP |
691 XT_HASHLIMIT_HASH_SPT))
Jan Engelhardtccb79bd2007-07-07 22:16:00 -0700692 return false;
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100693 if (!r->cfg.gc_interval)
Jan Engelhardtccb79bd2007-07-07 22:16:00 -0700694 return false;
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100695 if (!r->cfg.expire)
Jan Engelhardtccb79bd2007-07-07 22:16:00 -0700696 return false;
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100697 if (r->name[sizeof(r->name) - 1] != '\0')
Jan Engelhardtccb79bd2007-07-07 22:16:00 -0700698 return false;
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100699
700 /* This is the best we've got: We cannot release and re-grab lock,
701 * since checkentry() is called before x_tables.c grabs xt_mutex.
702 * We also cannot grab the hashtable spinlock, since htable_create will
703 * call vmalloc, and that can sleep. And we cannot just re-search
704 * the list of htable's in htable_create(), since then we would
705 * create duplicate proc files. -HW */
706 mutex_lock(&hlimit_mutex);
707 r->hinfo = htable_find_get(r->name, match->family);
Jan Engelhardt09e410d2008-01-31 04:48:13 -0800708 if (!r->hinfo && htable_create_v0(r, match->family) != 0) {
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100709 mutex_unlock(&hlimit_mutex);
Jan Engelhardtccb79bd2007-07-07 22:16:00 -0700710 return false;
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100711 }
712 mutex_unlock(&hlimit_mutex);
713
714 /* Ugly hack: For SMP, we only want to use one set */
715 r->u.master = r;
Jan Engelhardtccb79bd2007-07-07 22:16:00 -0700716 return true;
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100717}
718
Jan Engelhardt09e410d2008-01-31 04:48:13 -0800719static bool
720hashlimit_mt_check(const char *tablename, const void *inf,
721 const struct xt_match *match, void *matchinfo,
722 unsigned int hook_mask)
723{
724 struct xt_hashlimit_mtinfo1 *info = matchinfo;
725
726 /* Check for overflow. */
727 if (info->cfg.burst == 0 ||
728 user2credits(info->cfg.avg * info->cfg.burst) <
729 user2credits(info->cfg.avg)) {
730 printk(KERN_ERR "xt_hashlimit: overflow, try lower: %u/%u\n",
731 info->cfg.avg, info->cfg.burst);
732 return false;
733 }
734 if (info->cfg.gc_interval == 0 || info->cfg.expire == 0)
735 return false;
736 if (info->name[sizeof(info->name)-1] != '\0')
737 return false;
Jan Engelhardtee999d82008-10-08 11:35:01 +0200738 if (match->family == NFPROTO_IPV4) {
Jan Engelhardt09e410d2008-01-31 04:48:13 -0800739 if (info->cfg.srcmask > 32 || info->cfg.dstmask > 32)
740 return false;
741 } else {
742 if (info->cfg.srcmask > 128 || info->cfg.dstmask > 128)
743 return false;
744 }
745
746 /* This is the best we've got: We cannot release and re-grab lock,
747 * since checkentry() is called before x_tables.c grabs xt_mutex.
748 * We also cannot grab the hashtable spinlock, since htable_create will
749 * call vmalloc, and that can sleep. And we cannot just re-search
750 * the list of htable's in htable_create(), since then we would
751 * create duplicate proc files. -HW */
752 mutex_lock(&hlimit_mutex);
753 info->hinfo = htable_find_get(info->name, match->family);
754 if (!info->hinfo && htable_create(info, match->family) != 0) {
755 mutex_unlock(&hlimit_mutex);
756 return false;
757 }
758 mutex_unlock(&hlimit_mutex);
Jan Engelhardt09e410d2008-01-31 04:48:13 -0800759 return true;
760}
761
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100762static void
Jan Engelhardt09e410d2008-01-31 04:48:13 -0800763hashlimit_mt_destroy_v0(const struct xt_match *match, void *matchinfo)
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100764{
Jan Engelhardta47362a2007-07-07 22:16:55 -0700765 const struct xt_hashlimit_info *r = matchinfo;
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100766
767 htable_put(r->hinfo);
768}
769
Jan Engelhardt09e410d2008-01-31 04:48:13 -0800770static void
771hashlimit_mt_destroy(const struct xt_match *match, void *matchinfo)
772{
773 const struct xt_hashlimit_mtinfo1 *info = matchinfo;
774
775 htable_put(info->hinfo);
776}
777
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100778#ifdef CONFIG_COMPAT
779struct compat_xt_hashlimit_info {
780 char name[IFNAMSIZ];
781 struct hashlimit_cfg cfg;
782 compat_uptr_t hinfo;
783 compat_uptr_t master;
784};
785
Jan Engelhardtd3c5ee62007-12-04 23:24:03 -0800786static void hashlimit_mt_compat_from_user(void *dst, void *src)
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100787{
788 int off = offsetof(struct compat_xt_hashlimit_info, hinfo);
789
790 memcpy(dst, src, off);
791 memset(dst + off, 0, sizeof(struct compat_xt_hashlimit_info) - off);
792}
793
Jan Engelhardtd3c5ee62007-12-04 23:24:03 -0800794static int hashlimit_mt_compat_to_user(void __user *dst, void *src)
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100795{
796 int off = offsetof(struct compat_xt_hashlimit_info, hinfo);
797
798 return copy_to_user(dst, src, off) ? -EFAULT : 0;
799}
800#endif
801
Jan Engelhardtd3c5ee62007-12-04 23:24:03 -0800802static struct xt_match hashlimit_mt_reg[] __read_mostly = {
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100803 {
804 .name = "hashlimit",
Jan Engelhardt09e410d2008-01-31 04:48:13 -0800805 .revision = 0,
Jan Engelhardtee999d82008-10-08 11:35:01 +0200806 .family = NFPROTO_IPV4,
Jan Engelhardt09e410d2008-01-31 04:48:13 -0800807 .match = hashlimit_mt_v0,
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100808 .matchsize = sizeof(struct xt_hashlimit_info),
809#ifdef CONFIG_COMPAT
810 .compatsize = sizeof(struct compat_xt_hashlimit_info),
Jan Engelhardtd3c5ee62007-12-04 23:24:03 -0800811 .compat_from_user = hashlimit_mt_compat_from_user,
812 .compat_to_user = hashlimit_mt_compat_to_user,
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100813#endif
Jan Engelhardt09e410d2008-01-31 04:48:13 -0800814 .checkentry = hashlimit_mt_check_v0,
815 .destroy = hashlimit_mt_destroy_v0,
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100816 .me = THIS_MODULE
817 },
Jan Engelhardt09e410d2008-01-31 04:48:13 -0800818 {
819 .name = "hashlimit",
820 .revision = 1,
Jan Engelhardtee999d82008-10-08 11:35:01 +0200821 .family = NFPROTO_IPV4,
Jan Engelhardt09e410d2008-01-31 04:48:13 -0800822 .match = hashlimit_mt,
823 .matchsize = sizeof(struct xt_hashlimit_mtinfo1),
824 .checkentry = hashlimit_mt_check,
825 .destroy = hashlimit_mt_destroy,
826 .me = THIS_MODULE,
827 },
Eric Dumazet7b21e092007-12-17 22:45:28 -0800828#if defined(CONFIG_IP6_NF_IPTABLES) || defined(CONFIG_IP6_NF_IPTABLES_MODULE)
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100829 {
830 .name = "hashlimit",
Jan Engelhardtee999d82008-10-08 11:35:01 +0200831 .family = NFPROTO_IPV6,
Jan Engelhardt09e410d2008-01-31 04:48:13 -0800832 .match = hashlimit_mt_v0,
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100833 .matchsize = sizeof(struct xt_hashlimit_info),
834#ifdef CONFIG_COMPAT
835 .compatsize = sizeof(struct compat_xt_hashlimit_info),
Jan Engelhardtd3c5ee62007-12-04 23:24:03 -0800836 .compat_from_user = hashlimit_mt_compat_from_user,
837 .compat_to_user = hashlimit_mt_compat_to_user,
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100838#endif
Jan Engelhardt09e410d2008-01-31 04:48:13 -0800839 .checkentry = hashlimit_mt_check_v0,
840 .destroy = hashlimit_mt_destroy_v0,
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100841 .me = THIS_MODULE
842 },
Jan Engelhardt09e410d2008-01-31 04:48:13 -0800843 {
844 .name = "hashlimit",
845 .revision = 1,
Jan Engelhardtee999d82008-10-08 11:35:01 +0200846 .family = NFPROTO_IPV6,
Jan Engelhardt09e410d2008-01-31 04:48:13 -0800847 .match = hashlimit_mt,
848 .matchsize = sizeof(struct xt_hashlimit_mtinfo1),
849 .checkentry = hashlimit_mt_check,
850 .destroy = hashlimit_mt_destroy,
851 .me = THIS_MODULE,
852 },
Eric Dumazet7b21e092007-12-17 22:45:28 -0800853#endif
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100854};
855
856/* PROC stuff */
857static void *dl_seq_start(struct seq_file *s, loff_t *pos)
Stephen Hemmingerf4f6fb72008-01-31 04:08:39 -0800858 __acquires(htable->lock)
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100859{
860 struct proc_dir_entry *pde = s->private;
861 struct xt_hashlimit_htable *htable = pde->data;
862 unsigned int *bucket;
863
864 spin_lock_bh(&htable->lock);
865 if (*pos >= htable->cfg.size)
866 return NULL;
867
868 bucket = kmalloc(sizeof(unsigned int), GFP_ATOMIC);
869 if (!bucket)
870 return ERR_PTR(-ENOMEM);
871
872 *bucket = *pos;
873 return bucket;
874}
875
876static void *dl_seq_next(struct seq_file *s, void *v, loff_t *pos)
877{
878 struct proc_dir_entry *pde = s->private;
879 struct xt_hashlimit_htable *htable = pde->data;
880 unsigned int *bucket = (unsigned int *)v;
881
882 *pos = ++(*bucket);
883 if (*pos >= htable->cfg.size) {
884 kfree(v);
885 return NULL;
886 }
887 return bucket;
888}
889
890static void dl_seq_stop(struct seq_file *s, void *v)
Stephen Hemmingerf4f6fb72008-01-31 04:08:39 -0800891 __releases(htable->lock)
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100892{
893 struct proc_dir_entry *pde = s->private;
894 struct xt_hashlimit_htable *htable = pde->data;
895 unsigned int *bucket = (unsigned int *)v;
896
897 kfree(bucket);
898 spin_unlock_bh(&htable->lock);
899}
900
Jan Engelhardt76108ce2008-10-08 11:35:00 +0200901static int dl_seq_real_show(struct dsthash_ent *ent, u_int8_t family,
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100902 struct seq_file *s)
903{
904 /* recalculate to show accurate numbers */
905 rateinfo_recalc(ent, jiffies);
906
907 switch (family) {
Jan Engelhardtee999d82008-10-08 11:35:01 +0200908 case NFPROTO_IPV4:
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100909 return seq_printf(s, "%ld %u.%u.%u.%u:%u->"
910 "%u.%u.%u.%u:%u %u %u %u\n",
911 (long)(ent->expires - jiffies)/HZ,
Jan Engelhardt09e410d2008-01-31 04:48:13 -0800912 NIPQUAD(ent->dst.ip.src),
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100913 ntohs(ent->dst.src_port),
Jan Engelhardt09e410d2008-01-31 04:48:13 -0800914 NIPQUAD(ent->dst.ip.dst),
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100915 ntohs(ent->dst.dst_port),
916 ent->rateinfo.credit, ent->rateinfo.credit_cap,
917 ent->rateinfo.cost);
Eric Dumazet7b21e092007-12-17 22:45:28 -0800918#if defined(CONFIG_IP6_NF_IPTABLES) || defined(CONFIG_IP6_NF_IPTABLES_MODULE)
Jan Engelhardtee999d82008-10-08 11:35:01 +0200919 case NFPROTO_IPV6:
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100920 return seq_printf(s, "%ld " NIP6_FMT ":%u->"
921 NIP6_FMT ":%u %u %u %u\n",
922 (long)(ent->expires - jiffies)/HZ,
Jan Engelhardt09e410d2008-01-31 04:48:13 -0800923 NIP6(*(struct in6_addr *)&ent->dst.ip6.src),
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100924 ntohs(ent->dst.src_port),
Jan Engelhardt09e410d2008-01-31 04:48:13 -0800925 NIP6(*(struct in6_addr *)&ent->dst.ip6.dst),
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100926 ntohs(ent->dst.dst_port),
927 ent->rateinfo.credit, ent->rateinfo.credit_cap,
928 ent->rateinfo.cost);
Eric Dumazet7b21e092007-12-17 22:45:28 -0800929#endif
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100930 default:
931 BUG();
932 return 0;
933 }
934}
935
936static int dl_seq_show(struct seq_file *s, void *v)
937{
938 struct proc_dir_entry *pde = s->private;
939 struct xt_hashlimit_htable *htable = pde->data;
940 unsigned int *bucket = (unsigned int *)v;
941 struct dsthash_ent *ent;
942 struct hlist_node *pos;
943
944 if (!hlist_empty(&htable->hash[*bucket])) {
945 hlist_for_each_entry(ent, pos, &htable->hash[*bucket], node)
946 if (dl_seq_real_show(ent, htable->family, s))
947 return 1;
948 }
949 return 0;
950}
951
Philippe De Muyter56b3d972007-07-10 23:07:31 -0700952static const struct seq_operations dl_seq_ops = {
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100953 .start = dl_seq_start,
954 .next = dl_seq_next,
955 .stop = dl_seq_stop,
956 .show = dl_seq_show
957};
958
959static int dl_proc_open(struct inode *inode, struct file *file)
960{
961 int ret = seq_open(file, &dl_seq_ops);
962
963 if (!ret) {
964 struct seq_file *sf = file->private_data;
965 sf->private = PDE(inode);
966 }
967 return ret;
968}
969
Arjan van de Venda7071d2007-02-12 00:55:36 -0800970static const struct file_operations dl_file_ops = {
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100971 .owner = THIS_MODULE,
972 .open = dl_proc_open,
973 .read = seq_read,
974 .llseek = seq_lseek,
975 .release = seq_release
976};
977
Jan Engelhardtd3c5ee62007-12-04 23:24:03 -0800978static int __init hashlimit_mt_init(void)
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100979{
980 int err;
981
Jan Engelhardtd3c5ee62007-12-04 23:24:03 -0800982 err = xt_register_matches(hashlimit_mt_reg,
983 ARRAY_SIZE(hashlimit_mt_reg));
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100984 if (err < 0)
985 goto err1;
986
987 err = -ENOMEM;
988 hashlimit_cachep = kmem_cache_create("xt_hashlimit",
989 sizeof(struct dsthash_ent), 0, 0,
Paul Mundt20c2df82007-07-20 10:11:58 +0900990 NULL);
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100991 if (!hashlimit_cachep) {
992 printk(KERN_ERR "xt_hashlimit: unable to create slab cache\n");
993 goto err2;
994 }
Eric W. Biederman457c4cb2007-09-12 12:01:34 +0200995 hashlimit_procdir4 = proc_mkdir("ipt_hashlimit", init_net.proc_net);
Patrick McHardy39b46fc2006-11-29 02:35:36 +0100996 if (!hashlimit_procdir4) {
997 printk(KERN_ERR "xt_hashlimit: unable to create proc dir "
998 "entry\n");
999 goto err3;
1000 }
Eric Dumazet7b21e092007-12-17 22:45:28 -08001001 err = 0;
1002#if defined(CONFIG_IP6_NF_IPTABLES) || defined(CONFIG_IP6_NF_IPTABLES_MODULE)
Eric W. Biederman457c4cb2007-09-12 12:01:34 +02001003 hashlimit_procdir6 = proc_mkdir("ip6t_hashlimit", init_net.proc_net);
Patrick McHardy39b46fc2006-11-29 02:35:36 +01001004 if (!hashlimit_procdir6) {
Alexey Dobriyan9c2440b2007-01-02 00:42:00 -08001005 printk(KERN_ERR "xt_hashlimit: unable to create proc dir "
Patrick McHardy39b46fc2006-11-29 02:35:36 +01001006 "entry\n");
Eric Dumazet7b21e092007-12-17 22:45:28 -08001007 err = -ENOMEM;
Patrick McHardy39b46fc2006-11-29 02:35:36 +01001008 }
Eric Dumazet7b21e092007-12-17 22:45:28 -08001009#endif
1010 if (!err)
1011 return 0;
Eric W. Biederman457c4cb2007-09-12 12:01:34 +02001012 remove_proc_entry("ipt_hashlimit", init_net.proc_net);
Patrick McHardy39b46fc2006-11-29 02:35:36 +01001013err3:
1014 kmem_cache_destroy(hashlimit_cachep);
1015err2:
Jan Engelhardtd3c5ee62007-12-04 23:24:03 -08001016 xt_unregister_matches(hashlimit_mt_reg, ARRAY_SIZE(hashlimit_mt_reg));
Patrick McHardy39b46fc2006-11-29 02:35:36 +01001017err1:
1018 return err;
1019
1020}
1021
Jan Engelhardtd3c5ee62007-12-04 23:24:03 -08001022static void __exit hashlimit_mt_exit(void)
Patrick McHardy39b46fc2006-11-29 02:35:36 +01001023{
Eric W. Biederman457c4cb2007-09-12 12:01:34 +02001024 remove_proc_entry("ipt_hashlimit", init_net.proc_net);
Eric Dumazet7b21e092007-12-17 22:45:28 -08001025#if defined(CONFIG_IP6_NF_IPTABLES) || defined(CONFIG_IP6_NF_IPTABLES_MODULE)
Eric W. Biederman457c4cb2007-09-12 12:01:34 +02001026 remove_proc_entry("ip6t_hashlimit", init_net.proc_net);
Eric Dumazet7b21e092007-12-17 22:45:28 -08001027#endif
Patrick McHardy39b46fc2006-11-29 02:35:36 +01001028 kmem_cache_destroy(hashlimit_cachep);
Jan Engelhardtd3c5ee62007-12-04 23:24:03 -08001029 xt_unregister_matches(hashlimit_mt_reg, ARRAY_SIZE(hashlimit_mt_reg));
Patrick McHardy39b46fc2006-11-29 02:35:36 +01001030}
1031
Jan Engelhardtd3c5ee62007-12-04 23:24:03 -08001032module_init(hashlimit_mt_init);
1033module_exit(hashlimit_mt_exit);