Merge tag 'sound-3.16-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai...
[deliverable/linux.git] / net / netfilter / xt_recent.c
CommitLineData
404bdbfd
PM
1/*
2 * Copyright (c) 2006 Patrick McHardy <kaber@trash.net>
079aa88f 3 * Copyright © CC Computer Consultants GmbH, 2007 - 2008
404bdbfd
PM
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License version 2 as
7 * published by the Free Software Foundation.
8 *
9 * This is a replacement of the old ipt_recent module, which carried the
10 * following copyright notice:
11 *
12 * Author: Stephen Frost <sfrost@snowman.net>
13 * Copyright 2002-2003, Stephen Frost, 2.5.x port by laforge@netfilter.org
14 */
8bee4bad 15#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
404bdbfd 16#include <linux/init.h>
6709dbbb 17#include <linux/ip.h>
079aa88f
JE
18#include <linux/ipv6.h>
19#include <linux/module.h>
404bdbfd 20#include <linux/moduleparam.h>
1da177e4 21#include <linux/proc_fs.h>
404bdbfd
PM
22#include <linux/seq_file.h>
23#include <linux/string.h>
1da177e4 24#include <linux/ctype.h>
404bdbfd
PM
25#include <linux/list.h>
26#include <linux/random.h>
27#include <linux/jhash.h>
28#include <linux/bitops.h>
29#include <linux/skbuff.h>
30#include <linux/inet.h>
5a0e3ad6 31#include <linux/slab.h>
2727de76 32#include <linux/vmalloc.h>
457c4cbc 33#include <net/net_namespace.h>
7d07d563 34#include <net/netns/generic.h>
1da177e4 35
6709dbbb 36#include <linux/netfilter/x_tables.h>
e948b20a 37#include <linux/netfilter/xt_recent.h>
1da177e4 38
404bdbfd 39MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
408ffaa4 40MODULE_AUTHOR("Jan Engelhardt <jengelh@medozas.de>");
06bf514e 41MODULE_DESCRIPTION("Xtables: \"recently-seen\" host matching");
404bdbfd 42MODULE_LICENSE("GPL");
e948b20a 43MODULE_ALIAS("ipt_recent");
079aa88f 44MODULE_ALIAS("ip6t_recent");
1da177e4 45
e7be6994
PM
46static unsigned int ip_list_tot = 100;
47static unsigned int ip_pkt_list_tot = 20;
48static unsigned int ip_list_hash_size = 0;
49static unsigned int ip_list_perms = 0644;
b93ff783
DDG
50static unsigned int ip_list_uid = 0;
51static unsigned int ip_list_gid = 0;
e7be6994
PM
52module_param(ip_list_tot, uint, 0400);
53module_param(ip_pkt_list_tot, uint, 0400);
54module_param(ip_list_hash_size, uint, 0400);
55module_param(ip_list_perms, uint, 0400);
5dc7a6d5
JE
56module_param(ip_list_uid, uint, S_IRUGO | S_IWUSR);
57module_param(ip_list_gid, uint, S_IRUGO | S_IWUSR);
404bdbfd 58MODULE_PARM_DESC(ip_list_tot, "number of IPs to remember per list");
98e6d2d5 59MODULE_PARM_DESC(ip_pkt_list_tot, "number of packets per IP address to remember (max. 255)");
404bdbfd 60MODULE_PARM_DESC(ip_list_hash_size, "size of hash table used to look up IPs");
079aa88f 61MODULE_PARM_DESC(ip_list_perms, "permissions on /proc/net/xt_recent/* files");
5dc7a6d5
JE
62MODULE_PARM_DESC(ip_list_uid, "default owner of /proc/net/xt_recent/* files");
63MODULE_PARM_DESC(ip_list_gid, "default owning group of /proc/net/xt_recent/* files");
404bdbfd 64
404bdbfd
PM
65struct recent_entry {
66 struct list_head list;
67 struct list_head lru_list;
079aa88f
JE
68 union nf_inet_addr addr;
69 u_int16_t family;
404bdbfd
PM
70 u_int8_t ttl;
71 u_int8_t index;
72 u_int16_t nstamps;
73 unsigned long stamps[0];
1da177e4
LT
74};
75
404bdbfd
PM
76struct recent_table {
77 struct list_head list;
e948b20a 78 char name[XT_RECENT_NAME_LEN];
efdedd54 79 union nf_inet_addr mask;
404bdbfd
PM
80 unsigned int refcnt;
81 unsigned int entries;
82 struct list_head lru_list;
83 struct list_head iphash[0];
1da177e4
LT
84};
85
7d07d563
AD
86struct recent_net {
87 struct list_head tables;
88#ifdef CONFIG_PROC_FS
89 struct proc_dir_entry *xt_recent;
7d07d563
AD
90#endif
91};
92
93static int recent_net_id;
94static inline struct recent_net *recent_pernet(struct net *net)
95{
96 return net_generic(net, recent_net_id);
97}
98
1da177e4 99static DEFINE_SPINLOCK(recent_lock);
a0e889bb 100static DEFINE_MUTEX(recent_mutex);
1da177e4
LT
101
102#ifdef CONFIG_PROC_FS
079aa88f 103static const struct file_operations recent_old_fops, recent_mt_fops;
1da177e4
LT
104#endif
105
294188ae
JE
106static u_int32_t hash_rnd __read_mostly;
107static bool hash_rnd_inited __read_mostly;
079aa88f 108
294188ae 109static inline unsigned int recent_entry_hash4(const union nf_inet_addr *addr)
079aa88f 110{
079aa88f
JE
111 return jhash_1word((__force u32)addr->ip, hash_rnd) &
112 (ip_list_hash_size - 1);
113}
1da177e4 114
294188ae 115static inline unsigned int recent_entry_hash6(const union nf_inet_addr *addr)
1da177e4 116{
079aa88f
JE
117 return jhash2((u32 *)addr->ip6, ARRAY_SIZE(addr->ip6), hash_rnd) &
118 (ip_list_hash_size - 1);
1da177e4
LT
119}
120
404bdbfd 121static struct recent_entry *
079aa88f
JE
122recent_entry_lookup(const struct recent_table *table,
123 const union nf_inet_addr *addrp, u_int16_t family,
124 u_int8_t ttl)
1da177e4 125{
404bdbfd
PM
126 struct recent_entry *e;
127 unsigned int h;
128
ee999d8b 129 if (family == NFPROTO_IPV4)
079aa88f
JE
130 h = recent_entry_hash4(addrp);
131 else
132 h = recent_entry_hash6(addrp);
133
404bdbfd 134 list_for_each_entry(e, &table->iphash[h], list)
079aa88f
JE
135 if (e->family == family &&
136 memcmp(&e->addr, addrp, sizeof(e->addr)) == 0 &&
137 (ttl == e->ttl || ttl == 0 || e->ttl == 0))
404bdbfd
PM
138 return e;
139 return NULL;
140}
1da177e4 141
404bdbfd
PM
142static void recent_entry_remove(struct recent_table *t, struct recent_entry *e)
143{
144 list_del(&e->list);
145 list_del(&e->lru_list);
146 kfree(e);
147 t->entries--;
148}
1da177e4 149
0079c5ae
TG
150/*
151 * Drop entries with timestamps older then 'time'.
152 */
153static void recent_entry_reap(struct recent_table *t, unsigned long time)
154{
155 struct recent_entry *e;
156
157 /*
158 * The head of the LRU list is always the oldest entry.
159 */
160 e = list_entry(t->lru_list.next, struct recent_entry, lru_list);
161
162 /*
163 * The last time stamp is the most recent.
164 */
165 if (time_after(time, e->stamps[e->index-1]))
166 recent_entry_remove(t, e);
167}
168
404bdbfd 169static struct recent_entry *
079aa88f
JE
170recent_entry_init(struct recent_table *t, const union nf_inet_addr *addr,
171 u_int16_t family, u_int8_t ttl)
404bdbfd
PM
172{
173 struct recent_entry *e;
1da177e4 174
404bdbfd
PM
175 if (t->entries >= ip_list_tot) {
176 e = list_entry(t->lru_list.next, struct recent_entry, lru_list);
177 recent_entry_remove(t, e);
1da177e4 178 }
404bdbfd
PM
179 e = kmalloc(sizeof(*e) + sizeof(e->stamps[0]) * ip_pkt_list_tot,
180 GFP_ATOMIC);
181 if (e == NULL)
182 return NULL;
079aa88f 183 memcpy(&e->addr, addr, sizeof(e->addr));
404bdbfd
PM
184 e->ttl = ttl;
185 e->stamps[0] = jiffies;
186 e->nstamps = 1;
187 e->index = 1;
079aa88f 188 e->family = family;
ee999d8b 189 if (family == NFPROTO_IPV4)
079aa88f
JE
190 list_add_tail(&e->list, &t->iphash[recent_entry_hash4(addr)]);
191 else
192 list_add_tail(&e->list, &t->iphash[recent_entry_hash6(addr)]);
404bdbfd
PM
193 list_add_tail(&e->lru_list, &t->lru_list);
194 t->entries++;
195 return e;
196}
1da177e4 197
404bdbfd
PM
198static void recent_entry_update(struct recent_table *t, struct recent_entry *e)
199{
2c08522e 200 e->index %= ip_pkt_list_tot;
404bdbfd
PM
201 e->stamps[e->index++] = jiffies;
202 if (e->index > e->nstamps)
203 e->nstamps = e->index;
404bdbfd
PM
204 list_move_tail(&e->lru_list, &t->lru_list);
205}
1da177e4 206
7d07d563
AD
207static struct recent_table *recent_table_lookup(struct recent_net *recent_net,
208 const char *name)
404bdbfd
PM
209{
210 struct recent_table *t;
1da177e4 211
7d07d563 212 list_for_each_entry(t, &recent_net->tables, list)
404bdbfd
PM
213 if (!strcmp(t->name, name))
214 return t;
215 return NULL;
216}
1da177e4 217
404bdbfd
PM
218static void recent_table_flush(struct recent_table *t)
219{
220 struct recent_entry *e, *next;
221 unsigned int i;
1da177e4 222
7c4e36bc 223 for (i = 0; i < ip_list_hash_size; i++)
404bdbfd
PM
224 list_for_each_entry_safe(e, next, &t->iphash[i], list)
225 recent_entry_remove(t, e);
1da177e4
LT
226}
227
1d93a9cb 228static bool
62fc8051 229recent_mt(const struct sk_buff *skb, struct xt_action_param *par)
1da177e4 230{
7d07d563
AD
231 struct net *net = dev_net(par->in ? par->in : par->out);
232 struct recent_net *recent_net = recent_pernet(net);
efdedd54 233 const struct xt_recent_mtinfo_v1 *info = par->matchinfo;
404bdbfd
PM
234 struct recent_table *t;
235 struct recent_entry *e;
efdedd54 236 union nf_inet_addr addr = {}, addr_mask;
404bdbfd 237 u_int8_t ttl;
1d93a9cb 238 bool ret = info->invert;
1da177e4 239
aa5fa318 240 if (par->family == NFPROTO_IPV4) {
079aa88f
JE
241 const struct iphdr *iph = ip_hdr(skb);
242
243 if (info->side == XT_RECENT_DEST)
244 addr.ip = iph->daddr;
245 else
246 addr.ip = iph->saddr;
247
248 ttl = iph->ttl;
249 } else {
250 const struct ipv6hdr *iph = ipv6_hdr(skb);
251
252 if (info->side == XT_RECENT_DEST)
253 memcpy(&addr.in6, &iph->daddr, sizeof(addr.in6));
254 else
255 memcpy(&addr.in6, &iph->saddr, sizeof(addr.in6));
256
257 ttl = iph->hop_limit;
258 }
1da177e4 259
404bdbfd 260 /* use TTL as seen before forwarding */
f7108a20 261 if (par->out != NULL && skb->sk == NULL)
404bdbfd 262 ttl++;
1da177e4 263
1da177e4 264 spin_lock_bh(&recent_lock);
7d07d563 265 t = recent_table_lookup(recent_net, info->name);
efdedd54
DF
266
267 nf_inet_addr_mask(&addr, &addr_mask, &t->mask);
268
269 e = recent_entry_lookup(t, &addr_mask, par->family,
079aa88f 270 (info->check_set & XT_RECENT_TTL) ? ttl : 0);
404bdbfd 271 if (e == NULL) {
e948b20a 272 if (!(info->check_set & XT_RECENT_SET))
404bdbfd 273 goto out;
efdedd54 274 e = recent_entry_init(t, &addr_mask, par->family, ttl);
404bdbfd 275 if (e == NULL)
b4ba2611 276 par->hotdrop = true;
1d93a9cb 277 ret = !ret;
404bdbfd 278 goto out;
1da177e4
LT
279 }
280
e948b20a 281 if (info->check_set & XT_RECENT_SET)
1d93a9cb 282 ret = !ret;
e948b20a 283 else if (info->check_set & XT_RECENT_REMOVE) {
404bdbfd 284 recent_entry_remove(t, e);
1d93a9cb 285 ret = !ret;
e948b20a 286 } else if (info->check_set & (XT_RECENT_CHECK | XT_RECENT_UPDATE)) {
855304af 287 unsigned long time = jiffies - info->seconds * HZ;
404bdbfd
PM
288 unsigned int i, hits = 0;
289
290 for (i = 0; i < e->nstamps; i++) {
855304af 291 if (info->seconds && time_after(time, e->stamps[i]))
404bdbfd 292 continue;
ef169150 293 if (!info->hit_count || ++hits >= info->hit_count) {
1d93a9cb 294 ret = !ret;
404bdbfd 295 break;
1da177e4 296 }
1da177e4 297 }
0079c5ae
TG
298
299 /* info->seconds must be non-zero */
300 if (info->check_set & XT_RECENT_REAP)
301 recent_entry_reap(t, time);
1da177e4
LT
302 }
303
e948b20a
JE
304 if (info->check_set & XT_RECENT_SET ||
305 (info->check_set & XT_RECENT_UPDATE && ret)) {
404bdbfd
PM
306 recent_entry_update(t, e);
307 e->ttl = ttl;
308 }
309out:
310 spin_unlock_bh(&recent_lock);
311 return ret;
1da177e4
LT
312}
313
2727de76
ED
314static void recent_table_free(void *addr)
315{
4cb28970 316 kvfree(addr);
2727de76
ED
317}
318
efdedd54
DF
319static int recent_mt_check(const struct xt_mtchk_param *par,
320 const struct xt_recent_mtinfo_v1 *info)
1da177e4 321{
7d07d563 322 struct recent_net *recent_net = recent_pernet(par->net);
404bdbfd 323 struct recent_table *t;
b0ceb560
AD
324#ifdef CONFIG_PROC_FS
325 struct proc_dir_entry *pde;
da742808
EB
326 kuid_t uid;
327 kgid_t gid;
b0ceb560 328#endif
95c96174 329 unsigned int i;
bd414ee6 330 int ret = -EINVAL;
2727de76 331 size_t sz;
1da177e4 332
294188ae
JE
333 if (unlikely(!hash_rnd_inited)) {
334 get_random_bytes(&hash_rnd, sizeof(hash_rnd));
335 hash_rnd_inited = true;
336 }
606a9a02 337 if (info->check_set & ~XT_RECENT_VALID_FLAGS) {
ff67e4e4
JE
338 pr_info("Unsupported user space flags (%08x)\n",
339 info->check_set);
bd414ee6 340 return -EINVAL;
606a9a02 341 }
404bdbfd 342 if (hweight8(info->check_set &
e948b20a
JE
343 (XT_RECENT_SET | XT_RECENT_REMOVE |
344 XT_RECENT_CHECK | XT_RECENT_UPDATE)) != 1)
bd414ee6 345 return -EINVAL;
e948b20a 346 if ((info->check_set & (XT_RECENT_SET | XT_RECENT_REMOVE)) &&
0079c5ae
TG
347 (info->seconds || info->hit_count ||
348 (info->check_set & XT_RECENT_MODIFIERS)))
bd414ee6 349 return -EINVAL;
0079c5ae 350 if ((info->check_set & XT_RECENT_REAP) && !info->seconds)
bd414ee6 351 return -EINVAL;
98e6d2d5 352 if (info->hit_count > ip_pkt_list_tot) {
ff67e4e4 353 pr_info("hitcount (%u) is larger than "
98e6d2d5
JE
354 "packets to be remembered (%u)\n",
355 info->hit_count, ip_pkt_list_tot);
bd414ee6 356 return -EINVAL;
98e6d2d5 357 }
404bdbfd 358 if (info->name[0] == '\0' ||
e948b20a 359 strnlen(info->name, XT_RECENT_NAME_LEN) == XT_RECENT_NAME_LEN)
bd414ee6 360 return -EINVAL;
1da177e4 361
a0e889bb 362 mutex_lock(&recent_mutex);
7d07d563 363 t = recent_table_lookup(recent_net, info->name);
404bdbfd
PM
364 if (t != NULL) {
365 t->refcnt++;
bd414ee6 366 ret = 0;
404bdbfd 367 goto out;
1da177e4
LT
368 }
369
2727de76
ED
370 sz = sizeof(*t) + sizeof(t->iphash[0]) * ip_list_hash_size;
371 if (sz <= PAGE_SIZE)
372 t = kzalloc(sz, GFP_KERNEL);
373 else
374 t = vzalloc(sz);
4a5a5c73
JE
375 if (t == NULL) {
376 ret = -ENOMEM;
404bdbfd 377 goto out;
4a5a5c73 378 }
2b2283d0 379 t->refcnt = 1;
efdedd54
DF
380
381 memcpy(&t->mask, &info->mask, sizeof(t->mask));
404bdbfd
PM
382 strcpy(t->name, info->name);
383 INIT_LIST_HEAD(&t->lru_list);
384 for (i = 0; i < ip_list_hash_size; i++)
385 INIT_LIST_HEAD(&t->iphash[i]);
386#ifdef CONFIG_PROC_FS
da742808
EB
387 uid = make_kuid(&init_user_ns, ip_list_uid);
388 gid = make_kgid(&init_user_ns, ip_list_gid);
389 if (!uid_valid(uid) || !gid_valid(gid)) {
2727de76 390 recent_table_free(t);
da742808
EB
391 ret = -EINVAL;
392 goto out;
393 }
7d07d563 394 pde = proc_create_data(t->name, ip_list_perms, recent_net->xt_recent,
b09eec16 395 &recent_mt_fops, t);
b0ceb560 396 if (pde == NULL) {
2727de76 397 recent_table_free(t);
4a5a5c73 398 ret = -ENOMEM;
404bdbfd 399 goto out;
1da177e4 400 }
271a15ea 401 proc_set_user(pde, uid, gid);
1da177e4 402#endif
a0e889bb 403 spin_lock_bh(&recent_lock);
7d07d563 404 list_add_tail(&t->list, &recent_net->tables);
a0e889bb 405 spin_unlock_bh(&recent_lock);
bd414ee6 406 ret = 0;
404bdbfd 407out:
a0e889bb 408 mutex_unlock(&recent_mutex);
404bdbfd
PM
409 return ret;
410}
1da177e4 411
efdedd54
DF
412static int recent_mt_check_v0(const struct xt_mtchk_param *par)
413{
414 const struct xt_recent_mtinfo_v0 *info_v0 = par->matchinfo;
415 struct xt_recent_mtinfo_v1 info_v1;
416
417 /* Copy revision 0 structure to revision 1 */
418 memcpy(&info_v1, info_v0, sizeof(struct xt_recent_mtinfo));
419 /* Set default mask to ensure backward compatible behaviour */
420 memset(info_v1.mask.all, 0xFF, sizeof(info_v1.mask.all));
421
422 return recent_mt_check(par, &info_v1);
423}
424
425static int recent_mt_check_v1(const struct xt_mtchk_param *par)
426{
427 return recent_mt_check(par, par->matchinfo);
428}
429
6be3d859 430static void recent_mt_destroy(const struct xt_mtdtor_param *par)
404bdbfd 431{
7d07d563 432 struct recent_net *recent_net = recent_pernet(par->net);
efdedd54 433 const struct xt_recent_mtinfo_v1 *info = par->matchinfo;
404bdbfd 434 struct recent_table *t;
1da177e4 435
a0e889bb 436 mutex_lock(&recent_mutex);
7d07d563 437 t = recent_table_lookup(recent_net, info->name);
404bdbfd 438 if (--t->refcnt == 0) {
a0e889bb 439 spin_lock_bh(&recent_lock);
404bdbfd 440 list_del(&t->list);
a0e889bb 441 spin_unlock_bh(&recent_lock);
404bdbfd 442#ifdef CONFIG_PROC_FS
665e205c
VL
443 if (recent_net->xt_recent != NULL)
444 remove_proc_entry(t->name, recent_net->xt_recent);
1da177e4 445#endif
a8ddc916 446 recent_table_flush(t);
2727de76 447 recent_table_free(t);
1da177e4 448 }
a0e889bb 449 mutex_unlock(&recent_mutex);
404bdbfd 450}
1da177e4 451
404bdbfd
PM
452#ifdef CONFIG_PROC_FS
453struct recent_iter_state {
079aa88f 454 const struct recent_table *table;
404bdbfd
PM
455 unsigned int bucket;
456};
1da177e4 457
404bdbfd 458static void *recent_seq_start(struct seq_file *seq, loff_t *pos)
855304af 459 __acquires(recent_lock)
404bdbfd
PM
460{
461 struct recent_iter_state *st = seq->private;
a47362a2 462 const struct recent_table *t = st->table;
404bdbfd
PM
463 struct recent_entry *e;
464 loff_t p = *pos;
1da177e4 465
1da177e4 466 spin_lock_bh(&recent_lock);
1da177e4 467
7c4e36bc
JE
468 for (st->bucket = 0; st->bucket < ip_list_hash_size; st->bucket++)
469 list_for_each_entry(e, &t->iphash[st->bucket], list)
404bdbfd
PM
470 if (p-- == 0)
471 return e;
404bdbfd
PM
472 return NULL;
473}
1da177e4 474
404bdbfd
PM
475static void *recent_seq_next(struct seq_file *seq, void *v, loff_t *pos)
476{
477 struct recent_iter_state *st = seq->private;
3cf93c96 478 const struct recent_table *t = st->table;
079aa88f
JE
479 const struct recent_entry *e = v;
480 const struct list_head *head = e->list.next;
404bdbfd
PM
481
482 while (head == &t->iphash[st->bucket]) {
483 if (++st->bucket >= ip_list_hash_size)
484 return NULL;
485 head = t->iphash[st->bucket].next;
486 }
487 (*pos)++;
488 return list_entry(head, struct recent_entry, list);
1da177e4
LT
489}
490
404bdbfd 491static void recent_seq_stop(struct seq_file *s, void *v)
855304af 492 __releases(recent_lock)
1da177e4 493{
404bdbfd
PM
494 spin_unlock_bh(&recent_lock);
495}
1da177e4 496
404bdbfd
PM
497static int recent_seq_show(struct seq_file *seq, void *v)
498{
3cf93c96 499 const struct recent_entry *e = v;
404bdbfd
PM
500 unsigned int i;
501
502 i = (e->index - 1) % ip_pkt_list_tot;
ee999d8b 503 if (e->family == NFPROTO_IPV4)
14d5e834
HH
504 seq_printf(seq, "src=%pI4 ttl: %u last_seen: %lu oldest_pkt: %u",
505 &e->addr.ip, e->ttl, e->stamps[i], e->index);
079aa88f 506 else
5b095d98 507 seq_printf(seq, "src=%pI6 ttl: %u last_seen: %lu oldest_pkt: %u",
38ff4fa4 508 &e->addr.in6, e->ttl, e->stamps[i], e->index);
404bdbfd
PM
509 for (i = 0; i < e->nstamps; i++)
510 seq_printf(seq, "%s %lu", i ? "," : "", e->stamps[i]);
511 seq_printf(seq, "\n");
512 return 0;
513}
1da177e4 514
56b3d975 515static const struct seq_operations recent_seq_ops = {
404bdbfd
PM
516 .start = recent_seq_start,
517 .next = recent_seq_next,
518 .stop = recent_seq_stop,
519 .show = recent_seq_show,
520};
1da177e4 521
404bdbfd
PM
522static int recent_seq_open(struct inode *inode, struct file *file)
523{
404bdbfd 524 struct recent_iter_state *st;
404bdbfd 525
e2da5913 526 st = __seq_open_private(file, &recent_seq_ops, sizeof(*st));
404bdbfd
PM
527 if (st == NULL)
528 return -ENOMEM;
3af8e31c 529
d9dda78b 530 st->table = PDE_DATA(inode);
e2da5913 531 return 0;
404bdbfd 532}
1da177e4 533
079aa88f
JE
534static ssize_t
535recent_mt_proc_write(struct file *file, const char __user *input,
536 size_t size, loff_t *loff)
537{
d9dda78b 538 struct recent_table *t = PDE_DATA(file_inode(file));
079aa88f
JE
539 struct recent_entry *e;
540 char buf[sizeof("+b335:1d35:1e55:dead:c0de:1715:5afe:c0de")];
541 const char *c = buf;
325fb5b4 542 union nf_inet_addr addr = {};
079aa88f
JE
543 u_int16_t family;
544 bool add, succ;
545
546 if (size == 0)
547 return 0;
548 if (size > sizeof(buf))
549 size = sizeof(buf);
550 if (copy_from_user(buf, input, size) != 0)
551 return -EFAULT;
552
553 /* Strict protocol! */
554 if (*loff != 0)
555 return -ESPIPE;
556 switch (*c) {
557 case '/': /* flush table */
558 spin_lock_bh(&recent_lock);
559 recent_table_flush(t);
560 spin_unlock_bh(&recent_lock);
561 return size;
562 case '-': /* remove address */
563 add = false;
564 break;
565 case '+': /* add address */
566 add = true;
567 break;
568 default:
8bee4bad 569 pr_info("Need \"+ip\", \"-ip\" or \"/\"\n");
079aa88f
JE
570 return -EINVAL;
571 }
572
573 ++c;
574 --size;
575 if (strnchr(c, size, ':') != NULL) {
ee999d8b 576 family = NFPROTO_IPV6;
079aa88f
JE
577 succ = in6_pton(c, size, (void *)&addr, '\n', NULL);
578 } else {
ee999d8b 579 family = NFPROTO_IPV4;
079aa88f
JE
580 succ = in4_pton(c, size, (void *)&addr, '\n', NULL);
581 }
582
583 if (!succ) {
8bee4bad 584 pr_info("illegal address written to procfs\n");
079aa88f
JE
585 return -EINVAL;
586 }
587
588 spin_lock_bh(&recent_lock);
589 e = recent_entry_lookup(t, &addr, family, 0);
590 if (e == NULL) {
591 if (add)
592 recent_entry_init(t, &addr, family, 0);
593 } else {
594 if (add)
595 recent_entry_update(t, e);
596 else
597 recent_entry_remove(t, e);
598 }
599 spin_unlock_bh(&recent_lock);
600 /* Note we removed one above */
601 *loff += size + 1;
602 return size + 1;
603}
604
605static const struct file_operations recent_mt_fops = {
606 .open = recent_seq_open,
607 .read = seq_read,
608 .write = recent_mt_proc_write,
609 .release = seq_release_private,
610 .owner = THIS_MODULE,
6038f373 611 .llseek = seq_lseek,
079aa88f 612};
7d07d563
AD
613
614static int __net_init recent_proc_net_init(struct net *net)
615{
616 struct recent_net *recent_net = recent_pernet(net);
617
618 recent_net->xt_recent = proc_mkdir("xt_recent", net->proc_net);
619 if (!recent_net->xt_recent)
620 return -ENOMEM;
7d07d563
AD
621 return 0;
622}
623
624static void __net_exit recent_proc_net_exit(struct net *net)
625{
665e205c
VL
626 struct recent_net *recent_net = recent_pernet(net);
627 struct recent_table *t;
628
629 /* recent_net_exit() is called before recent_mt_destroy(). Make sure
630 * that the parent xt_recent proc entry is is empty before trying to
631 * remove it.
632 */
633 spin_lock_bh(&recent_lock);
634 list_for_each_entry(t, &recent_net->tables, list)
635 remove_proc_entry(t->name, recent_net->xt_recent);
636
637 recent_net->xt_recent = NULL;
638 spin_unlock_bh(&recent_lock);
639
ece31ffd 640 remove_proc_entry("xt_recent", net->proc_net);
7d07d563
AD
641}
642#else
643static inline int recent_proc_net_init(struct net *net)
644{
645 return 0;
646}
647
648static inline void recent_proc_net_exit(struct net *net)
649{
650}
1da177e4 651#endif /* CONFIG_PROC_FS */
1da177e4 652
7d07d563
AD
653static int __net_init recent_net_init(struct net *net)
654{
655 struct recent_net *recent_net = recent_pernet(net);
656
657 INIT_LIST_HEAD(&recent_net->tables);
658 return recent_proc_net_init(net);
659}
660
661static void __net_exit recent_net_exit(struct net *net)
662{
7d07d563
AD
663 recent_proc_net_exit(net);
664}
665
666static struct pernet_operations recent_net_ops = {
667 .init = recent_net_init,
668 .exit = recent_net_exit,
669 .id = &recent_net_id,
670 .size = sizeof(struct recent_net),
671};
672
079aa88f
JE
673static struct xt_match recent_mt_reg[] __read_mostly = {
674 {
675 .name = "recent",
676 .revision = 0,
ee999d8b 677 .family = NFPROTO_IPV4,
079aa88f
JE
678 .match = recent_mt,
679 .matchsize = sizeof(struct xt_recent_mtinfo),
efdedd54 680 .checkentry = recent_mt_check_v0,
079aa88f
JE
681 .destroy = recent_mt_destroy,
682 .me = THIS_MODULE,
683 },
684 {
685 .name = "recent",
686 .revision = 0,
ee999d8b 687 .family = NFPROTO_IPV6,
079aa88f
JE
688 .match = recent_mt,
689 .matchsize = sizeof(struct xt_recent_mtinfo),
efdedd54
DF
690 .checkentry = recent_mt_check_v0,
691 .destroy = recent_mt_destroy,
692 .me = THIS_MODULE,
693 },
694 {
695 .name = "recent",
696 .revision = 1,
697 .family = NFPROTO_IPV4,
698 .match = recent_mt,
699 .matchsize = sizeof(struct xt_recent_mtinfo_v1),
700 .checkentry = recent_mt_check_v1,
079aa88f
JE
701 .destroy = recent_mt_destroy,
702 .me = THIS_MODULE,
703 },
efdedd54
DF
704 {
705 .name = "recent",
706 .revision = 1,
707 .family = NFPROTO_IPV6,
708 .match = recent_mt,
709 .matchsize = sizeof(struct xt_recent_mtinfo_v1),
710 .checkentry = recent_mt_check_v1,
711 .destroy = recent_mt_destroy,
712 .me = THIS_MODULE,
713 }
1da177e4
LT
714};
715
d3c5ee6d 716static int __init recent_mt_init(void)
1da177e4 717{
404bdbfd 718 int err;
1da177e4 719
404bdbfd
PM
720 if (!ip_list_tot || !ip_pkt_list_tot || ip_pkt_list_tot > 255)
721 return -EINVAL;
722 ip_list_hash_size = 1 << fls(ip_list_tot);
1da177e4 723
7d07d563 724 err = register_pernet_subsys(&recent_net_ops);
1da177e4 725 if (err)
404bdbfd 726 return err;
7d07d563
AD
727 err = xt_register_matches(recent_mt_reg, ARRAY_SIZE(recent_mt_reg));
728 if (err)
729 unregister_pernet_subsys(&recent_net_ops);
1da177e4
LT
730 return err;
731}
732
d3c5ee6d 733static void __exit recent_mt_exit(void)
1da177e4 734{
079aa88f 735 xt_unregister_matches(recent_mt_reg, ARRAY_SIZE(recent_mt_reg));
7d07d563 736 unregister_pernet_subsys(&recent_net_ops);
1da177e4
LT
737}
738
d3c5ee6d
JE
739module_init(recent_mt_init);
740module_exit(recent_mt_exit);
This page took 0.958756 seconds and 5 git commands to generate.