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1da177e4 LT |
1 | /* |
2 | * Packet matching code. | |
3 | * | |
4 | * Copyright (C) 1999 Paul `Rusty' Russell & Michael J. Neuling | |
5 | * Copyright (C) 2000-2002 Netfilter core team <coreteam@netfilter.org> | |
6 | * | |
7 | * This program is free software; you can redistribute it and/or modify | |
8 | * it under the terms of the GNU General Public License version 2 as | |
9 | * published by the Free Software Foundation. | |
10 | * | |
11 | * 19 Jan 2002 Harald Welte <laforge@gnumonks.org> | |
12 | * - increase module usage count as soon as we have rules inside | |
13 | * a table | |
14 | * 06 Jun 2002 Andras Kis-Szabo <kisza@sch.bme.hu> | |
15 | * - new extension header parser code | |
16 | */ | |
17 | #include <linux/config.h> | |
18 | #include <linux/skbuff.h> | |
19 | #include <linux/kmod.h> | |
20 | #include <linux/vmalloc.h> | |
21 | #include <linux/netdevice.h> | |
22 | #include <linux/module.h> | |
23 | #include <linux/tcp.h> | |
24 | #include <linux/udp.h> | |
25 | #include <linux/icmpv6.h> | |
26 | #include <net/ip.h> | |
27 | #include <net/ipv6.h> | |
28 | #include <asm/uaccess.h> | |
29 | #include <asm/semaphore.h> | |
30 | #include <linux/proc_fs.h> | |
31 | ||
32 | #include <linux/netfilter_ipv6/ip6_tables.h> | |
33 | ||
34 | MODULE_LICENSE("GPL"); | |
35 | MODULE_AUTHOR("Netfilter Core Team <coreteam@netfilter.org>"); | |
36 | MODULE_DESCRIPTION("IPv6 packet filter"); | |
37 | ||
38 | #define IPV6_HDR_LEN (sizeof(struct ipv6hdr)) | |
39 | #define IPV6_OPTHDR_LEN (sizeof(struct ipv6_opt_hdr)) | |
40 | ||
41 | /*#define DEBUG_IP_FIREWALL*/ | |
42 | /*#define DEBUG_ALLOW_ALL*/ /* Useful for remote debugging */ | |
43 | /*#define DEBUG_IP_FIREWALL_USER*/ | |
44 | ||
45 | #ifdef DEBUG_IP_FIREWALL | |
46 | #define dprintf(format, args...) printk(format , ## args) | |
47 | #else | |
48 | #define dprintf(format, args...) | |
49 | #endif | |
50 | ||
51 | #ifdef DEBUG_IP_FIREWALL_USER | |
52 | #define duprintf(format, args...) printk(format , ## args) | |
53 | #else | |
54 | #define duprintf(format, args...) | |
55 | #endif | |
56 | ||
57 | #ifdef CONFIG_NETFILTER_DEBUG | |
58 | #define IP_NF_ASSERT(x) \ | |
59 | do { \ | |
60 | if (!(x)) \ | |
61 | printk("IP_NF_ASSERT: %s:%s:%u\n", \ | |
62 | __FUNCTION__, __FILE__, __LINE__); \ | |
63 | } while(0) | |
64 | #else | |
65 | #define IP_NF_ASSERT(x) | |
66 | #endif | |
67 | #define SMP_ALIGN(x) (((x) + SMP_CACHE_BYTES-1) & ~(SMP_CACHE_BYTES-1)) | |
68 | ||
69 | static DECLARE_MUTEX(ip6t_mutex); | |
70 | ||
71 | /* Must have mutex */ | |
72 | #define ASSERT_READ_LOCK(x) IP_NF_ASSERT(down_trylock(&ip6t_mutex) != 0) | |
73 | #define ASSERT_WRITE_LOCK(x) IP_NF_ASSERT(down_trylock(&ip6t_mutex) != 0) | |
74 | #include <linux/netfilter_ipv4/lockhelp.h> | |
75 | #include <linux/netfilter_ipv4/listhelp.h> | |
76 | ||
77 | #if 0 | |
78 | /* All the better to debug you with... */ | |
79 | #define static | |
80 | #define inline | |
81 | #endif | |
82 | ||
83 | /* Locking is simple: we assume at worst case there will be one packet | |
84 | in user context and one from bottom halves (or soft irq if Alexey's | |
85 | softnet patch was applied). | |
86 | ||
87 | We keep a set of rules for each CPU, so we can avoid write-locking | |
88 | them; doing a readlock_bh() stops packets coming through if we're | |
89 | in user context. | |
90 | ||
91 | To be cache friendly on SMP, we arrange them like so: | |
92 | [ n-entries ] | |
93 | ... cache-align padding ... | |
94 | [ n-entries ] | |
95 | ||
96 | Hence the start of any table is given by get_table() below. */ | |
97 | ||
98 | /* The table itself */ | |
99 | struct ip6t_table_info | |
100 | { | |
101 | /* Size per table */ | |
102 | unsigned int size; | |
103 | /* Number of entries: FIXME. --RR */ | |
104 | unsigned int number; | |
105 | /* Initial number of entries. Needed for module usage count */ | |
106 | unsigned int initial_entries; | |
107 | ||
108 | /* Entry points and underflows */ | |
109 | unsigned int hook_entry[NF_IP6_NUMHOOKS]; | |
110 | unsigned int underflow[NF_IP6_NUMHOOKS]; | |
111 | ||
112 | /* ip6t_entry tables: one per CPU */ | |
113 | char entries[0] ____cacheline_aligned; | |
114 | }; | |
115 | ||
116 | static LIST_HEAD(ip6t_target); | |
117 | static LIST_HEAD(ip6t_match); | |
118 | static LIST_HEAD(ip6t_tables); | |
119 | #define ADD_COUNTER(c,b,p) do { (c).bcnt += (b); (c).pcnt += (p); } while(0) | |
120 | ||
121 | #ifdef CONFIG_SMP | |
122 | #define TABLE_OFFSET(t,p) (SMP_ALIGN((t)->size)*(p)) | |
123 | #else | |
124 | #define TABLE_OFFSET(t,p) 0 | |
125 | #endif | |
126 | ||
127 | #if 0 | |
128 | #define down(x) do { printk("DOWN:%u:" #x "\n", __LINE__); down(x); } while(0) | |
129 | #define down_interruptible(x) ({ int __r; printk("DOWNi:%u:" #x "\n", __LINE__); __r = down_interruptible(x); if (__r != 0) printk("ABORT-DOWNi:%u\n", __LINE__); __r; }) | |
130 | #define up(x) do { printk("UP:%u:" #x "\n", __LINE__); up(x); } while(0) | |
131 | #endif | |
132 | ||
133 | static int ip6_masked_addrcmp(struct in6_addr addr1, struct in6_addr mask, | |
134 | struct in6_addr addr2) | |
135 | { | |
136 | int i; | |
137 | for( i = 0; i < 16; i++){ | |
138 | if((addr1.s6_addr[i] & mask.s6_addr[i]) != | |
139 | (addr2.s6_addr[i] & mask.s6_addr[i])) | |
140 | return 1; | |
141 | } | |
142 | return 0; | |
143 | } | |
144 | ||
145 | /* Check for an extension */ | |
146 | int | |
147 | ip6t_ext_hdr(u8 nexthdr) | |
148 | { | |
149 | return ( (nexthdr == IPPROTO_HOPOPTS) || | |
150 | (nexthdr == IPPROTO_ROUTING) || | |
151 | (nexthdr == IPPROTO_FRAGMENT) || | |
152 | (nexthdr == IPPROTO_ESP) || | |
153 | (nexthdr == IPPROTO_AH) || | |
154 | (nexthdr == IPPROTO_NONE) || | |
155 | (nexthdr == IPPROTO_DSTOPTS) ); | |
156 | } | |
157 | ||
158 | /* Returns whether matches rule or not. */ | |
159 | static inline int | |
160 | ip6_packet_match(const struct sk_buff *skb, | |
161 | const char *indev, | |
162 | const char *outdev, | |
163 | const struct ip6t_ip6 *ip6info, | |
164 | unsigned int *protoff, | |
165 | int *fragoff) | |
166 | { | |
167 | size_t i; | |
168 | unsigned long ret; | |
169 | const struct ipv6hdr *ipv6 = skb->nh.ipv6h; | |
170 | ||
171 | #define FWINV(bool,invflg) ((bool) ^ !!(ip6info->invflags & invflg)) | |
172 | ||
173 | if (FWINV(ip6_masked_addrcmp(ipv6->saddr,ip6info->smsk,ip6info->src), | |
174 | IP6T_INV_SRCIP) | |
175 | || FWINV(ip6_masked_addrcmp(ipv6->daddr,ip6info->dmsk,ip6info->dst), | |
176 | IP6T_INV_DSTIP)) { | |
177 | dprintf("Source or dest mismatch.\n"); | |
178 | /* | |
179 | dprintf("SRC: %u. Mask: %u. Target: %u.%s\n", ip->saddr, | |
180 | ipinfo->smsk.s_addr, ipinfo->src.s_addr, | |
181 | ipinfo->invflags & IP6T_INV_SRCIP ? " (INV)" : ""); | |
182 | dprintf("DST: %u. Mask: %u. Target: %u.%s\n", ip->daddr, | |
183 | ipinfo->dmsk.s_addr, ipinfo->dst.s_addr, | |
184 | ipinfo->invflags & IP6T_INV_DSTIP ? " (INV)" : "");*/ | |
185 | return 0; | |
186 | } | |
187 | ||
188 | /* Look for ifname matches; this should unroll nicely. */ | |
189 | for (i = 0, ret = 0; i < IFNAMSIZ/sizeof(unsigned long); i++) { | |
190 | ret |= (((const unsigned long *)indev)[i] | |
191 | ^ ((const unsigned long *)ip6info->iniface)[i]) | |
192 | & ((const unsigned long *)ip6info->iniface_mask)[i]; | |
193 | } | |
194 | ||
195 | if (FWINV(ret != 0, IP6T_INV_VIA_IN)) { | |
196 | dprintf("VIA in mismatch (%s vs %s).%s\n", | |
197 | indev, ip6info->iniface, | |
198 | ip6info->invflags&IP6T_INV_VIA_IN ?" (INV)":""); | |
199 | return 0; | |
200 | } | |
201 | ||
202 | for (i = 0, ret = 0; i < IFNAMSIZ/sizeof(unsigned long); i++) { | |
203 | ret |= (((const unsigned long *)outdev)[i] | |
204 | ^ ((const unsigned long *)ip6info->outiface)[i]) | |
205 | & ((const unsigned long *)ip6info->outiface_mask)[i]; | |
206 | } | |
207 | ||
208 | if (FWINV(ret != 0, IP6T_INV_VIA_OUT)) { | |
209 | dprintf("VIA out mismatch (%s vs %s).%s\n", | |
210 | outdev, ip6info->outiface, | |
211 | ip6info->invflags&IP6T_INV_VIA_OUT ?" (INV)":""); | |
212 | return 0; | |
213 | } | |
214 | ||
215 | /* ... might want to do something with class and flowlabel here ... */ | |
216 | ||
217 | /* look for the desired protocol header */ | |
218 | if((ip6info->flags & IP6T_F_PROTO)) { | |
219 | u_int8_t currenthdr = ipv6->nexthdr; | |
220 | struct ipv6_opt_hdr _hdr, *hp; | |
221 | u_int16_t ptr; /* Header offset in skb */ | |
222 | u_int16_t hdrlen; /* Header */ | |
223 | u_int16_t _fragoff = 0, *fp = NULL; | |
224 | ||
225 | ptr = IPV6_HDR_LEN; | |
226 | ||
227 | while (ip6t_ext_hdr(currenthdr)) { | |
228 | /* Is there enough space for the next ext header? */ | |
229 | if (skb->len - ptr < IPV6_OPTHDR_LEN) | |
230 | return 0; | |
231 | ||
232 | /* NONE or ESP: there isn't protocol part */ | |
233 | /* If we want to count these packets in '-p all', | |
234 | * we will change the return 0 to 1*/ | |
235 | if ((currenthdr == IPPROTO_NONE) || | |
236 | (currenthdr == IPPROTO_ESP)) | |
237 | break; | |
238 | ||
239 | hp = skb_header_pointer(skb, ptr, sizeof(_hdr), &_hdr); | |
240 | BUG_ON(hp == NULL); | |
241 | ||
242 | /* Size calculation */ | |
243 | if (currenthdr == IPPROTO_FRAGMENT) { | |
244 | fp = skb_header_pointer(skb, | |
245 | ptr+offsetof(struct frag_hdr, | |
246 | frag_off), | |
247 | sizeof(_fragoff), | |
248 | &_fragoff); | |
249 | if (fp == NULL) | |
250 | return 0; | |
251 | ||
252 | _fragoff = ntohs(*fp) & ~0x7; | |
253 | hdrlen = 8; | |
254 | } else if (currenthdr == IPPROTO_AH) | |
255 | hdrlen = (hp->hdrlen+2)<<2; | |
256 | else | |
257 | hdrlen = ipv6_optlen(hp); | |
258 | ||
259 | currenthdr = hp->nexthdr; | |
260 | ptr += hdrlen; | |
261 | /* ptr is too large */ | |
262 | if ( ptr > skb->len ) | |
263 | return 0; | |
264 | if (_fragoff) { | |
265 | if (ip6t_ext_hdr(currenthdr)) | |
266 | return 0; | |
267 | break; | |
268 | } | |
269 | } | |
270 | ||
271 | *protoff = ptr; | |
272 | *fragoff = _fragoff; | |
273 | ||
274 | /* currenthdr contains the protocol header */ | |
275 | ||
276 | dprintf("Packet protocol %hi ?= %s%hi.\n", | |
277 | currenthdr, | |
278 | ip6info->invflags & IP6T_INV_PROTO ? "!":"", | |
279 | ip6info->proto); | |
280 | ||
281 | if (ip6info->proto == currenthdr) { | |
282 | if(ip6info->invflags & IP6T_INV_PROTO) { | |
283 | return 0; | |
284 | } | |
285 | return 1; | |
286 | } | |
287 | ||
288 | /* We need match for the '-p all', too! */ | |
289 | if ((ip6info->proto != 0) && | |
290 | !(ip6info->invflags & IP6T_INV_PROTO)) | |
291 | return 0; | |
292 | } | |
293 | return 1; | |
294 | } | |
295 | ||
296 | /* should be ip6 safe */ | |
297 | static inline int | |
298 | ip6_checkentry(const struct ip6t_ip6 *ipv6) | |
299 | { | |
300 | if (ipv6->flags & ~IP6T_F_MASK) { | |
301 | duprintf("Unknown flag bits set: %08X\n", | |
302 | ipv6->flags & ~IP6T_F_MASK); | |
303 | return 0; | |
304 | } | |
305 | if (ipv6->invflags & ~IP6T_INV_MASK) { | |
306 | duprintf("Unknown invflag bits set: %08X\n", | |
307 | ipv6->invflags & ~IP6T_INV_MASK); | |
308 | return 0; | |
309 | } | |
310 | return 1; | |
311 | } | |
312 | ||
313 | static unsigned int | |
314 | ip6t_error(struct sk_buff **pskb, | |
315 | const struct net_device *in, | |
316 | const struct net_device *out, | |
317 | unsigned int hooknum, | |
318 | const void *targinfo, | |
319 | void *userinfo) | |
320 | { | |
321 | if (net_ratelimit()) | |
322 | printk("ip6_tables: error: `%s'\n", (char *)targinfo); | |
323 | ||
324 | return NF_DROP; | |
325 | } | |
326 | ||
327 | static inline | |
328 | int do_match(struct ip6t_entry_match *m, | |
329 | const struct sk_buff *skb, | |
330 | const struct net_device *in, | |
331 | const struct net_device *out, | |
332 | int offset, | |
333 | unsigned int protoff, | |
334 | int *hotdrop) | |
335 | { | |
336 | /* Stop iteration if it doesn't match */ | |
337 | if (!m->u.kernel.match->match(skb, in, out, m->data, | |
338 | offset, protoff, hotdrop)) | |
339 | return 1; | |
340 | else | |
341 | return 0; | |
342 | } | |
343 | ||
344 | static inline struct ip6t_entry * | |
345 | get_entry(void *base, unsigned int offset) | |
346 | { | |
347 | return (struct ip6t_entry *)(base + offset); | |
348 | } | |
349 | ||
350 | /* Returns one of the generic firewall policies, like NF_ACCEPT. */ | |
351 | unsigned int | |
352 | ip6t_do_table(struct sk_buff **pskb, | |
353 | unsigned int hook, | |
354 | const struct net_device *in, | |
355 | const struct net_device *out, | |
356 | struct ip6t_table *table, | |
357 | void *userdata) | |
358 | { | |
359 | static const char nulldevname[IFNAMSIZ]; | |
360 | int offset = 0; | |
361 | unsigned int protoff = 0; | |
362 | int hotdrop = 0; | |
363 | /* Initializing verdict to NF_DROP keeps gcc happy. */ | |
364 | unsigned int verdict = NF_DROP; | |
365 | const char *indev, *outdev; | |
366 | void *table_base; | |
367 | struct ip6t_entry *e, *back; | |
368 | ||
369 | /* Initialization */ | |
370 | indev = in ? in->name : nulldevname; | |
371 | outdev = out ? out->name : nulldevname; | |
372 | ||
373 | /* We handle fragments by dealing with the first fragment as | |
374 | * if it was a normal packet. All other fragments are treated | |
375 | * normally, except that they will NEVER match rules that ask | |
376 | * things we don't know, ie. tcp syn flag or ports). If the | |
377 | * rule is also a fragment-specific rule, non-fragments won't | |
378 | * match it. */ | |
379 | ||
380 | read_lock_bh(&table->lock); | |
381 | IP_NF_ASSERT(table->valid_hooks & (1 << hook)); | |
382 | table_base = (void *)table->private->entries | |
383 | + TABLE_OFFSET(table->private, smp_processor_id()); | |
384 | e = get_entry(table_base, table->private->hook_entry[hook]); | |
385 | ||
386 | #ifdef CONFIG_NETFILTER_DEBUG | |
387 | /* Check noone else using our table */ | |
388 | if (((struct ip6t_entry *)table_base)->comefrom != 0xdead57ac | |
389 | && ((struct ip6t_entry *)table_base)->comefrom != 0xeeeeeeec) { | |
390 | printk("ASSERT: CPU #%u, %s comefrom(%p) = %X\n", | |
391 | smp_processor_id(), | |
392 | table->name, | |
393 | &((struct ip6t_entry *)table_base)->comefrom, | |
394 | ((struct ip6t_entry *)table_base)->comefrom); | |
395 | } | |
396 | ((struct ip6t_entry *)table_base)->comefrom = 0x57acc001; | |
397 | #endif | |
398 | ||
399 | /* For return from builtin chain */ | |
400 | back = get_entry(table_base, table->private->underflow[hook]); | |
401 | ||
402 | do { | |
403 | IP_NF_ASSERT(e); | |
404 | IP_NF_ASSERT(back); | |
405 | (*pskb)->nfcache |= e->nfcache; | |
406 | if (ip6_packet_match(*pskb, indev, outdev, &e->ipv6, | |
407 | &protoff, &offset)) { | |
408 | struct ip6t_entry_target *t; | |
409 | ||
410 | if (IP6T_MATCH_ITERATE(e, do_match, | |
411 | *pskb, in, out, | |
412 | offset, protoff, &hotdrop) != 0) | |
413 | goto no_match; | |
414 | ||
415 | ADD_COUNTER(e->counters, | |
416 | ntohs((*pskb)->nh.ipv6h->payload_len) | |
417 | + IPV6_HDR_LEN, | |
418 | 1); | |
419 | ||
420 | t = ip6t_get_target(e); | |
421 | IP_NF_ASSERT(t->u.kernel.target); | |
422 | /* Standard target? */ | |
423 | if (!t->u.kernel.target->target) { | |
424 | int v; | |
425 | ||
426 | v = ((struct ip6t_standard_target *)t)->verdict; | |
427 | if (v < 0) { | |
428 | /* Pop from stack? */ | |
429 | if (v != IP6T_RETURN) { | |
430 | verdict = (unsigned)(-v) - 1; | |
431 | break; | |
432 | } | |
433 | e = back; | |
434 | back = get_entry(table_base, | |
435 | back->comefrom); | |
436 | continue; | |
437 | } | |
438 | if (table_base + v | |
439 | != (void *)e + e->next_offset) { | |
440 | /* Save old back ptr in next entry */ | |
441 | struct ip6t_entry *next | |
442 | = (void *)e + e->next_offset; | |
443 | next->comefrom | |
444 | = (void *)back - table_base; | |
445 | /* set back pointer to next entry */ | |
446 | back = next; | |
447 | } | |
448 | ||
449 | e = get_entry(table_base, v); | |
450 | } else { | |
451 | /* Targets which reenter must return | |
452 | abs. verdicts */ | |
453 | #ifdef CONFIG_NETFILTER_DEBUG | |
454 | ((struct ip6t_entry *)table_base)->comefrom | |
455 | = 0xeeeeeeec; | |
456 | #endif | |
457 | verdict = t->u.kernel.target->target(pskb, | |
458 | in, out, | |
459 | hook, | |
460 | t->data, | |
461 | userdata); | |
462 | ||
463 | #ifdef CONFIG_NETFILTER_DEBUG | |
464 | if (((struct ip6t_entry *)table_base)->comefrom | |
465 | != 0xeeeeeeec | |
466 | && verdict == IP6T_CONTINUE) { | |
467 | printk("Target %s reentered!\n", | |
468 | t->u.kernel.target->name); | |
469 | verdict = NF_DROP; | |
470 | } | |
471 | ((struct ip6t_entry *)table_base)->comefrom | |
472 | = 0x57acc001; | |
473 | #endif | |
474 | if (verdict == IP6T_CONTINUE) | |
475 | e = (void *)e + e->next_offset; | |
476 | else | |
477 | /* Verdict */ | |
478 | break; | |
479 | } | |
480 | } else { | |
481 | ||
482 | no_match: | |
483 | e = (void *)e + e->next_offset; | |
484 | } | |
485 | } while (!hotdrop); | |
486 | ||
487 | #ifdef CONFIG_NETFILTER_DEBUG | |
488 | ((struct ip6t_entry *)table_base)->comefrom = 0xdead57ac; | |
489 | #endif | |
490 | read_unlock_bh(&table->lock); | |
491 | ||
492 | #ifdef DEBUG_ALLOW_ALL | |
493 | return NF_ACCEPT; | |
494 | #else | |
495 | if (hotdrop) | |
496 | return NF_DROP; | |
497 | else return verdict; | |
498 | #endif | |
499 | } | |
500 | ||
501 | /* If it succeeds, returns element and locks mutex */ | |
502 | static inline void * | |
503 | find_inlist_lock_noload(struct list_head *head, | |
504 | const char *name, | |
505 | int *error, | |
506 | struct semaphore *mutex) | |
507 | { | |
508 | void *ret; | |
509 | ||
510 | #if 1 | |
511 | duprintf("find_inlist: searching for `%s' in %s.\n", | |
512 | name, head == &ip6t_target ? "ip6t_target" | |
513 | : head == &ip6t_match ? "ip6t_match" | |
514 | : head == &ip6t_tables ? "ip6t_tables" : "UNKNOWN"); | |
515 | #endif | |
516 | ||
517 | *error = down_interruptible(mutex); | |
518 | if (*error != 0) | |
519 | return NULL; | |
520 | ||
521 | ret = list_named_find(head, name); | |
522 | if (!ret) { | |
523 | *error = -ENOENT; | |
524 | up(mutex); | |
525 | } | |
526 | return ret; | |
527 | } | |
528 | ||
529 | #ifndef CONFIG_KMOD | |
530 | #define find_inlist_lock(h,n,p,e,m) find_inlist_lock_noload((h),(n),(e),(m)) | |
531 | #else | |
532 | static void * | |
533 | find_inlist_lock(struct list_head *head, | |
534 | const char *name, | |
535 | const char *prefix, | |
536 | int *error, | |
537 | struct semaphore *mutex) | |
538 | { | |
539 | void *ret; | |
540 | ||
541 | ret = find_inlist_lock_noload(head, name, error, mutex); | |
542 | if (!ret) { | |
543 | duprintf("find_inlist: loading `%s%s'.\n", prefix, name); | |
544 | request_module("%s%s", prefix, name); | |
545 | ret = find_inlist_lock_noload(head, name, error, mutex); | |
546 | } | |
547 | ||
548 | return ret; | |
549 | } | |
550 | #endif | |
551 | ||
552 | static inline struct ip6t_table * | |
553 | ip6t_find_table_lock(const char *name, int *error, struct semaphore *mutex) | |
554 | { | |
555 | return find_inlist_lock(&ip6t_tables, name, "ip6table_", error, mutex); | |
556 | } | |
557 | ||
558 | static inline struct ip6t_match * | |
559 | find_match_lock(const char *name, int *error, struct semaphore *mutex) | |
560 | { | |
561 | return find_inlist_lock(&ip6t_match, name, "ip6t_", error, mutex); | |
562 | } | |
563 | ||
564 | static struct ip6t_target * | |
565 | ip6t_find_target_lock(const char *name, int *error, struct semaphore *mutex) | |
566 | { | |
567 | return find_inlist_lock(&ip6t_target, name, "ip6t_", error, mutex); | |
568 | } | |
569 | ||
570 | /* All zeroes == unconditional rule. */ | |
571 | static inline int | |
572 | unconditional(const struct ip6t_ip6 *ipv6) | |
573 | { | |
574 | unsigned int i; | |
575 | ||
576 | for (i = 0; i < sizeof(*ipv6); i++) | |
577 | if (((char *)ipv6)[i]) | |
578 | break; | |
579 | ||
580 | return (i == sizeof(*ipv6)); | |
581 | } | |
582 | ||
583 | /* Figures out from what hook each rule can be called: returns 0 if | |
584 | there are loops. Puts hook bitmask in comefrom. */ | |
585 | static int | |
586 | mark_source_chains(struct ip6t_table_info *newinfo, unsigned int valid_hooks) | |
587 | { | |
588 | unsigned int hook; | |
589 | ||
590 | /* No recursion; use packet counter to save back ptrs (reset | |
591 | to 0 as we leave), and comefrom to save source hook bitmask */ | |
592 | for (hook = 0; hook < NF_IP6_NUMHOOKS; hook++) { | |
593 | unsigned int pos = newinfo->hook_entry[hook]; | |
594 | struct ip6t_entry *e | |
595 | = (struct ip6t_entry *)(newinfo->entries + pos); | |
596 | ||
597 | if (!(valid_hooks & (1 << hook))) | |
598 | continue; | |
599 | ||
600 | /* Set initial back pointer. */ | |
601 | e->counters.pcnt = pos; | |
602 | ||
603 | for (;;) { | |
604 | struct ip6t_standard_target *t | |
605 | = (void *)ip6t_get_target(e); | |
606 | ||
607 | if (e->comefrom & (1 << NF_IP6_NUMHOOKS)) { | |
608 | printk("iptables: loop hook %u pos %u %08X.\n", | |
609 | hook, pos, e->comefrom); | |
610 | return 0; | |
611 | } | |
612 | e->comefrom | |
613 | |= ((1 << hook) | (1 << NF_IP6_NUMHOOKS)); | |
614 | ||
615 | /* Unconditional return/END. */ | |
616 | if (e->target_offset == sizeof(struct ip6t_entry) | |
617 | && (strcmp(t->target.u.user.name, | |
618 | IP6T_STANDARD_TARGET) == 0) | |
619 | && t->verdict < 0 | |
620 | && unconditional(&e->ipv6)) { | |
621 | unsigned int oldpos, size; | |
622 | ||
623 | /* Return: backtrack through the last | |
624 | big jump. */ | |
625 | do { | |
626 | e->comefrom ^= (1<<NF_IP6_NUMHOOKS); | |
627 | #ifdef DEBUG_IP_FIREWALL_USER | |
628 | if (e->comefrom | |
629 | & (1 << NF_IP6_NUMHOOKS)) { | |
630 | duprintf("Back unset " | |
631 | "on hook %u " | |
632 | "rule %u\n", | |
633 | hook, pos); | |
634 | } | |
635 | #endif | |
636 | oldpos = pos; | |
637 | pos = e->counters.pcnt; | |
638 | e->counters.pcnt = 0; | |
639 | ||
640 | /* We're at the start. */ | |
641 | if (pos == oldpos) | |
642 | goto next; | |
643 | ||
644 | e = (struct ip6t_entry *) | |
645 | (newinfo->entries + pos); | |
646 | } while (oldpos == pos + e->next_offset); | |
647 | ||
648 | /* Move along one */ | |
649 | size = e->next_offset; | |
650 | e = (struct ip6t_entry *) | |
651 | (newinfo->entries + pos + size); | |
652 | e->counters.pcnt = pos; | |
653 | pos += size; | |
654 | } else { | |
655 | int newpos = t->verdict; | |
656 | ||
657 | if (strcmp(t->target.u.user.name, | |
658 | IP6T_STANDARD_TARGET) == 0 | |
659 | && newpos >= 0) { | |
660 | /* This a jump; chase it. */ | |
661 | duprintf("Jump rule %u -> %u\n", | |
662 | pos, newpos); | |
663 | } else { | |
664 | /* ... this is a fallthru */ | |
665 | newpos = pos + e->next_offset; | |
666 | } | |
667 | e = (struct ip6t_entry *) | |
668 | (newinfo->entries + newpos); | |
669 | e->counters.pcnt = pos; | |
670 | pos = newpos; | |
671 | } | |
672 | } | |
673 | next: | |
674 | duprintf("Finished chain %u\n", hook); | |
675 | } | |
676 | return 1; | |
677 | } | |
678 | ||
679 | static inline int | |
680 | cleanup_match(struct ip6t_entry_match *m, unsigned int *i) | |
681 | { | |
682 | if (i && (*i)-- == 0) | |
683 | return 1; | |
684 | ||
685 | if (m->u.kernel.match->destroy) | |
686 | m->u.kernel.match->destroy(m->data, | |
687 | m->u.match_size - sizeof(*m)); | |
688 | module_put(m->u.kernel.match->me); | |
689 | return 0; | |
690 | } | |
691 | ||
692 | static inline int | |
693 | standard_check(const struct ip6t_entry_target *t, | |
694 | unsigned int max_offset) | |
695 | { | |
696 | struct ip6t_standard_target *targ = (void *)t; | |
697 | ||
698 | /* Check standard info. */ | |
699 | if (t->u.target_size | |
700 | != IP6T_ALIGN(sizeof(struct ip6t_standard_target))) { | |
701 | duprintf("standard_check: target size %u != %u\n", | |
702 | t->u.target_size, | |
703 | IP6T_ALIGN(sizeof(struct ip6t_standard_target))); | |
704 | return 0; | |
705 | } | |
706 | ||
707 | if (targ->verdict >= 0 | |
708 | && targ->verdict > max_offset - sizeof(struct ip6t_entry)) { | |
709 | duprintf("ip6t_standard_check: bad verdict (%i)\n", | |
710 | targ->verdict); | |
711 | return 0; | |
712 | } | |
713 | ||
714 | if (targ->verdict < -NF_MAX_VERDICT - 1) { | |
715 | duprintf("ip6t_standard_check: bad negative verdict (%i)\n", | |
716 | targ->verdict); | |
717 | return 0; | |
718 | } | |
719 | return 1; | |
720 | } | |
721 | ||
722 | static inline int | |
723 | check_match(struct ip6t_entry_match *m, | |
724 | const char *name, | |
725 | const struct ip6t_ip6 *ipv6, | |
726 | unsigned int hookmask, | |
727 | unsigned int *i) | |
728 | { | |
729 | int ret; | |
730 | struct ip6t_match *match; | |
731 | ||
732 | match = find_match_lock(m->u.user.name, &ret, &ip6t_mutex); | |
733 | if (!match) { | |
734 | // duprintf("check_match: `%s' not found\n", m->u.name); | |
735 | return ret; | |
736 | } | |
737 | if (!try_module_get(match->me)) { | |
738 | up(&ip6t_mutex); | |
739 | return -ENOENT; | |
740 | } | |
741 | m->u.kernel.match = match; | |
742 | up(&ip6t_mutex); | |
743 | ||
744 | if (m->u.kernel.match->checkentry | |
745 | && !m->u.kernel.match->checkentry(name, ipv6, m->data, | |
746 | m->u.match_size - sizeof(*m), | |
747 | hookmask)) { | |
748 | module_put(m->u.kernel.match->me); | |
749 | duprintf("ip_tables: check failed for `%s'.\n", | |
750 | m->u.kernel.match->name); | |
751 | return -EINVAL; | |
752 | } | |
753 | ||
754 | (*i)++; | |
755 | return 0; | |
756 | } | |
757 | ||
758 | static struct ip6t_target ip6t_standard_target; | |
759 | ||
760 | static inline int | |
761 | check_entry(struct ip6t_entry *e, const char *name, unsigned int size, | |
762 | unsigned int *i) | |
763 | { | |
764 | struct ip6t_entry_target *t; | |
765 | struct ip6t_target *target; | |
766 | int ret; | |
767 | unsigned int j; | |
768 | ||
769 | if (!ip6_checkentry(&e->ipv6)) { | |
770 | duprintf("ip_tables: ip check failed %p %s.\n", e, name); | |
771 | return -EINVAL; | |
772 | } | |
773 | ||
774 | j = 0; | |
775 | ret = IP6T_MATCH_ITERATE(e, check_match, name, &e->ipv6, e->comefrom, &j); | |
776 | if (ret != 0) | |
777 | goto cleanup_matches; | |
778 | ||
779 | t = ip6t_get_target(e); | |
780 | target = ip6t_find_target_lock(t->u.user.name, &ret, &ip6t_mutex); | |
781 | if (!target) { | |
782 | duprintf("check_entry: `%s' not found\n", t->u.user.name); | |
783 | goto cleanup_matches; | |
784 | } | |
785 | if (!try_module_get(target->me)) { | |
786 | up(&ip6t_mutex); | |
787 | ret = -ENOENT; | |
788 | goto cleanup_matches; | |
789 | } | |
790 | t->u.kernel.target = target; | |
791 | up(&ip6t_mutex); | |
792 | if (!t->u.kernel.target) { | |
793 | ret = -EBUSY; | |
794 | goto cleanup_matches; | |
795 | } | |
796 | if (t->u.kernel.target == &ip6t_standard_target) { | |
797 | if (!standard_check(t, size)) { | |
798 | ret = -EINVAL; | |
799 | goto cleanup_matches; | |
800 | } | |
801 | } else if (t->u.kernel.target->checkentry | |
802 | && !t->u.kernel.target->checkentry(name, e, t->data, | |
803 | t->u.target_size | |
804 | - sizeof(*t), | |
805 | e->comefrom)) { | |
806 | module_put(t->u.kernel.target->me); | |
807 | duprintf("ip_tables: check failed for `%s'.\n", | |
808 | t->u.kernel.target->name); | |
809 | ret = -EINVAL; | |
810 | goto cleanup_matches; | |
811 | } | |
812 | ||
813 | (*i)++; | |
814 | return 0; | |
815 | ||
816 | cleanup_matches: | |
817 | IP6T_MATCH_ITERATE(e, cleanup_match, &j); | |
818 | return ret; | |
819 | } | |
820 | ||
821 | static inline int | |
822 | check_entry_size_and_hooks(struct ip6t_entry *e, | |
823 | struct ip6t_table_info *newinfo, | |
824 | unsigned char *base, | |
825 | unsigned char *limit, | |
826 | const unsigned int *hook_entries, | |
827 | const unsigned int *underflows, | |
828 | unsigned int *i) | |
829 | { | |
830 | unsigned int h; | |
831 | ||
832 | if ((unsigned long)e % __alignof__(struct ip6t_entry) != 0 | |
833 | || (unsigned char *)e + sizeof(struct ip6t_entry) >= limit) { | |
834 | duprintf("Bad offset %p\n", e); | |
835 | return -EINVAL; | |
836 | } | |
837 | ||
838 | if (e->next_offset | |
839 | < sizeof(struct ip6t_entry) + sizeof(struct ip6t_entry_target)) { | |
840 | duprintf("checking: element %p size %u\n", | |
841 | e, e->next_offset); | |
842 | return -EINVAL; | |
843 | } | |
844 | ||
845 | /* Check hooks & underflows */ | |
846 | for (h = 0; h < NF_IP6_NUMHOOKS; h++) { | |
847 | if ((unsigned char *)e - base == hook_entries[h]) | |
848 | newinfo->hook_entry[h] = hook_entries[h]; | |
849 | if ((unsigned char *)e - base == underflows[h]) | |
850 | newinfo->underflow[h] = underflows[h]; | |
851 | } | |
852 | ||
853 | /* FIXME: underflows must be unconditional, standard verdicts | |
854 | < 0 (not IP6T_RETURN). --RR */ | |
855 | ||
856 | /* Clear counters and comefrom */ | |
857 | e->counters = ((struct ip6t_counters) { 0, 0 }); | |
858 | e->comefrom = 0; | |
859 | ||
860 | (*i)++; | |
861 | return 0; | |
862 | } | |
863 | ||
864 | static inline int | |
865 | cleanup_entry(struct ip6t_entry *e, unsigned int *i) | |
866 | { | |
867 | struct ip6t_entry_target *t; | |
868 | ||
869 | if (i && (*i)-- == 0) | |
870 | return 1; | |
871 | ||
872 | /* Cleanup all matches */ | |
873 | IP6T_MATCH_ITERATE(e, cleanup_match, NULL); | |
874 | t = ip6t_get_target(e); | |
875 | if (t->u.kernel.target->destroy) | |
876 | t->u.kernel.target->destroy(t->data, | |
877 | t->u.target_size - sizeof(*t)); | |
878 | module_put(t->u.kernel.target->me); | |
879 | return 0; | |
880 | } | |
881 | ||
882 | /* Checks and translates the user-supplied table segment (held in | |
883 | newinfo) */ | |
884 | static int | |
885 | translate_table(const char *name, | |
886 | unsigned int valid_hooks, | |
887 | struct ip6t_table_info *newinfo, | |
888 | unsigned int size, | |
889 | unsigned int number, | |
890 | const unsigned int *hook_entries, | |
891 | const unsigned int *underflows) | |
892 | { | |
893 | unsigned int i; | |
894 | int ret; | |
895 | ||
896 | newinfo->size = size; | |
897 | newinfo->number = number; | |
898 | ||
899 | /* Init all hooks to impossible value. */ | |
900 | for (i = 0; i < NF_IP6_NUMHOOKS; i++) { | |
901 | newinfo->hook_entry[i] = 0xFFFFFFFF; | |
902 | newinfo->underflow[i] = 0xFFFFFFFF; | |
903 | } | |
904 | ||
905 | duprintf("translate_table: size %u\n", newinfo->size); | |
906 | i = 0; | |
907 | /* Walk through entries, checking offsets. */ | |
908 | ret = IP6T_ENTRY_ITERATE(newinfo->entries, newinfo->size, | |
909 | check_entry_size_and_hooks, | |
910 | newinfo, | |
911 | newinfo->entries, | |
912 | newinfo->entries + size, | |
913 | hook_entries, underflows, &i); | |
914 | if (ret != 0) | |
915 | return ret; | |
916 | ||
917 | if (i != number) { | |
918 | duprintf("translate_table: %u not %u entries\n", | |
919 | i, number); | |
920 | return -EINVAL; | |
921 | } | |
922 | ||
923 | /* Check hooks all assigned */ | |
924 | for (i = 0; i < NF_IP6_NUMHOOKS; i++) { | |
925 | /* Only hooks which are valid */ | |
926 | if (!(valid_hooks & (1 << i))) | |
927 | continue; | |
928 | if (newinfo->hook_entry[i] == 0xFFFFFFFF) { | |
929 | duprintf("Invalid hook entry %u %u\n", | |
930 | i, hook_entries[i]); | |
931 | return -EINVAL; | |
932 | } | |
933 | if (newinfo->underflow[i] == 0xFFFFFFFF) { | |
934 | duprintf("Invalid underflow %u %u\n", | |
935 | i, underflows[i]); | |
936 | return -EINVAL; | |
937 | } | |
938 | } | |
939 | ||
940 | if (!mark_source_chains(newinfo, valid_hooks)) | |
941 | return -ELOOP; | |
942 | ||
943 | /* Finally, each sanity check must pass */ | |
944 | i = 0; | |
945 | ret = IP6T_ENTRY_ITERATE(newinfo->entries, newinfo->size, | |
946 | check_entry, name, size, &i); | |
947 | ||
948 | if (ret != 0) { | |
949 | IP6T_ENTRY_ITERATE(newinfo->entries, newinfo->size, | |
950 | cleanup_entry, &i); | |
951 | return ret; | |
952 | } | |
953 | ||
954 | /* And one copy for every other CPU */ | |
955 | for (i = 1; i < num_possible_cpus(); i++) { | |
956 | memcpy(newinfo->entries + SMP_ALIGN(newinfo->size)*i, | |
957 | newinfo->entries, | |
958 | SMP_ALIGN(newinfo->size)); | |
959 | } | |
960 | ||
961 | return ret; | |
962 | } | |
963 | ||
964 | static struct ip6t_table_info * | |
965 | replace_table(struct ip6t_table *table, | |
966 | unsigned int num_counters, | |
967 | struct ip6t_table_info *newinfo, | |
968 | int *error) | |
969 | { | |
970 | struct ip6t_table_info *oldinfo; | |
971 | ||
972 | #ifdef CONFIG_NETFILTER_DEBUG | |
973 | { | |
974 | struct ip6t_entry *table_base; | |
975 | unsigned int i; | |
976 | ||
977 | for (i = 0; i < num_possible_cpus(); i++) { | |
978 | table_base = | |
979 | (void *)newinfo->entries | |
980 | + TABLE_OFFSET(newinfo, i); | |
981 | ||
982 | table_base->comefrom = 0xdead57ac; | |
983 | } | |
984 | } | |
985 | #endif | |
986 | ||
987 | /* Do the substitution. */ | |
988 | write_lock_bh(&table->lock); | |
989 | /* Check inside lock: is the old number correct? */ | |
990 | if (num_counters != table->private->number) { | |
991 | duprintf("num_counters != table->private->number (%u/%u)\n", | |
992 | num_counters, table->private->number); | |
993 | write_unlock_bh(&table->lock); | |
994 | *error = -EAGAIN; | |
995 | return NULL; | |
996 | } | |
997 | oldinfo = table->private; | |
998 | table->private = newinfo; | |
999 | newinfo->initial_entries = oldinfo->initial_entries; | |
1000 | write_unlock_bh(&table->lock); | |
1001 | ||
1002 | return oldinfo; | |
1003 | } | |
1004 | ||
1005 | /* Gets counters. */ | |
1006 | static inline int | |
1007 | add_entry_to_counter(const struct ip6t_entry *e, | |
1008 | struct ip6t_counters total[], | |
1009 | unsigned int *i) | |
1010 | { | |
1011 | ADD_COUNTER(total[*i], e->counters.bcnt, e->counters.pcnt); | |
1012 | ||
1013 | (*i)++; | |
1014 | return 0; | |
1015 | } | |
1016 | ||
1017 | static void | |
1018 | get_counters(const struct ip6t_table_info *t, | |
1019 | struct ip6t_counters counters[]) | |
1020 | { | |
1021 | unsigned int cpu; | |
1022 | unsigned int i; | |
1023 | ||
1024 | for (cpu = 0; cpu < num_possible_cpus(); cpu++) { | |
1025 | i = 0; | |
1026 | IP6T_ENTRY_ITERATE(t->entries + TABLE_OFFSET(t, cpu), | |
1027 | t->size, | |
1028 | add_entry_to_counter, | |
1029 | counters, | |
1030 | &i); | |
1031 | } | |
1032 | } | |
1033 | ||
1034 | static int | |
1035 | copy_entries_to_user(unsigned int total_size, | |
1036 | struct ip6t_table *table, | |
1037 | void __user *userptr) | |
1038 | { | |
1039 | unsigned int off, num, countersize; | |
1040 | struct ip6t_entry *e; | |
1041 | struct ip6t_counters *counters; | |
1042 | int ret = 0; | |
1043 | ||
1044 | /* We need atomic snapshot of counters: rest doesn't change | |
1045 | (other than comefrom, which userspace doesn't care | |
1046 | about). */ | |
1047 | countersize = sizeof(struct ip6t_counters) * table->private->number; | |
1048 | counters = vmalloc(countersize); | |
1049 | ||
1050 | if (counters == NULL) | |
1051 | return -ENOMEM; | |
1052 | ||
1053 | /* First, sum counters... */ | |
1054 | memset(counters, 0, countersize); | |
1055 | write_lock_bh(&table->lock); | |
1056 | get_counters(table->private, counters); | |
1057 | write_unlock_bh(&table->lock); | |
1058 | ||
1059 | /* ... then copy entire thing from CPU 0... */ | |
1060 | if (copy_to_user(userptr, table->private->entries, total_size) != 0) { | |
1061 | ret = -EFAULT; | |
1062 | goto free_counters; | |
1063 | } | |
1064 | ||
1065 | /* FIXME: use iterator macros --RR */ | |
1066 | /* ... then go back and fix counters and names */ | |
1067 | for (off = 0, num = 0; off < total_size; off += e->next_offset, num++){ | |
1068 | unsigned int i; | |
1069 | struct ip6t_entry_match *m; | |
1070 | struct ip6t_entry_target *t; | |
1071 | ||
1072 | e = (struct ip6t_entry *)(table->private->entries + off); | |
1073 | if (copy_to_user(userptr + off | |
1074 | + offsetof(struct ip6t_entry, counters), | |
1075 | &counters[num], | |
1076 | sizeof(counters[num])) != 0) { | |
1077 | ret = -EFAULT; | |
1078 | goto free_counters; | |
1079 | } | |
1080 | ||
1081 | for (i = sizeof(struct ip6t_entry); | |
1082 | i < e->target_offset; | |
1083 | i += m->u.match_size) { | |
1084 | m = (void *)e + i; | |
1085 | ||
1086 | if (copy_to_user(userptr + off + i | |
1087 | + offsetof(struct ip6t_entry_match, | |
1088 | u.user.name), | |
1089 | m->u.kernel.match->name, | |
1090 | strlen(m->u.kernel.match->name)+1) | |
1091 | != 0) { | |
1092 | ret = -EFAULT; | |
1093 | goto free_counters; | |
1094 | } | |
1095 | } | |
1096 | ||
1097 | t = ip6t_get_target(e); | |
1098 | if (copy_to_user(userptr + off + e->target_offset | |
1099 | + offsetof(struct ip6t_entry_target, | |
1100 | u.user.name), | |
1101 | t->u.kernel.target->name, | |
1102 | strlen(t->u.kernel.target->name)+1) != 0) { | |
1103 | ret = -EFAULT; | |
1104 | goto free_counters; | |
1105 | } | |
1106 | } | |
1107 | ||
1108 | free_counters: | |
1109 | vfree(counters); | |
1110 | return ret; | |
1111 | } | |
1112 | ||
1113 | static int | |
1114 | get_entries(const struct ip6t_get_entries *entries, | |
1115 | struct ip6t_get_entries __user *uptr) | |
1116 | { | |
1117 | int ret; | |
1118 | struct ip6t_table *t; | |
1119 | ||
1120 | t = ip6t_find_table_lock(entries->name, &ret, &ip6t_mutex); | |
1121 | if (t) { | |
1122 | duprintf("t->private->number = %u\n", | |
1123 | t->private->number); | |
1124 | if (entries->size == t->private->size) | |
1125 | ret = copy_entries_to_user(t->private->size, | |
1126 | t, uptr->entrytable); | |
1127 | else { | |
1128 | duprintf("get_entries: I've got %u not %u!\n", | |
1129 | t->private->size, | |
1130 | entries->size); | |
1131 | ret = -EINVAL; | |
1132 | } | |
1133 | up(&ip6t_mutex); | |
1134 | } else | |
1135 | duprintf("get_entries: Can't find %s!\n", | |
1136 | entries->name); | |
1137 | ||
1138 | return ret; | |
1139 | } | |
1140 | ||
1141 | static int | |
1142 | do_replace(void __user *user, unsigned int len) | |
1143 | { | |
1144 | int ret; | |
1145 | struct ip6t_replace tmp; | |
1146 | struct ip6t_table *t; | |
1147 | struct ip6t_table_info *newinfo, *oldinfo; | |
1148 | struct ip6t_counters *counters; | |
1149 | ||
1150 | if (copy_from_user(&tmp, user, sizeof(tmp)) != 0) | |
1151 | return -EFAULT; | |
1152 | ||
1153 | /* Pedantry: prevent them from hitting BUG() in vmalloc.c --RR */ | |
1154 | if ((SMP_ALIGN(tmp.size) >> PAGE_SHIFT) + 2 > num_physpages) | |
1155 | return -ENOMEM; | |
1156 | ||
1157 | newinfo = vmalloc(sizeof(struct ip6t_table_info) | |
1158 | + SMP_ALIGN(tmp.size) * num_possible_cpus()); | |
1159 | if (!newinfo) | |
1160 | return -ENOMEM; | |
1161 | ||
1162 | if (copy_from_user(newinfo->entries, user + sizeof(tmp), | |
1163 | tmp.size) != 0) { | |
1164 | ret = -EFAULT; | |
1165 | goto free_newinfo; | |
1166 | } | |
1167 | ||
1168 | counters = vmalloc(tmp.num_counters * sizeof(struct ip6t_counters)); | |
1169 | if (!counters) { | |
1170 | ret = -ENOMEM; | |
1171 | goto free_newinfo; | |
1172 | } | |
1173 | memset(counters, 0, tmp.num_counters * sizeof(struct ip6t_counters)); | |
1174 | ||
1175 | ret = translate_table(tmp.name, tmp.valid_hooks, | |
1176 | newinfo, tmp.size, tmp.num_entries, | |
1177 | tmp.hook_entry, tmp.underflow); | |
1178 | if (ret != 0) | |
1179 | goto free_newinfo_counters; | |
1180 | ||
1181 | duprintf("ip_tables: Translated table\n"); | |
1182 | ||
1183 | t = ip6t_find_table_lock(tmp.name, &ret, &ip6t_mutex); | |
1184 | if (!t) | |
1185 | goto free_newinfo_counters_untrans; | |
1186 | ||
1187 | /* You lied! */ | |
1188 | if (tmp.valid_hooks != t->valid_hooks) { | |
1189 | duprintf("Valid hook crap: %08X vs %08X\n", | |
1190 | tmp.valid_hooks, t->valid_hooks); | |
1191 | ret = -EINVAL; | |
1192 | goto free_newinfo_counters_untrans_unlock; | |
1193 | } | |
1194 | ||
1195 | /* Get a reference in advance, we're not allowed fail later */ | |
1196 | if (!try_module_get(t->me)) { | |
1197 | ret = -EBUSY; | |
1198 | goto free_newinfo_counters_untrans_unlock; | |
1199 | } | |
1200 | ||
1201 | oldinfo = replace_table(t, tmp.num_counters, newinfo, &ret); | |
1202 | if (!oldinfo) | |
1203 | goto put_module; | |
1204 | ||
1205 | /* Update module usage count based on number of rules */ | |
1206 | duprintf("do_replace: oldnum=%u, initnum=%u, newnum=%u\n", | |
1207 | oldinfo->number, oldinfo->initial_entries, newinfo->number); | |
1208 | if ((oldinfo->number > oldinfo->initial_entries) || | |
1209 | (newinfo->number <= oldinfo->initial_entries)) | |
1210 | module_put(t->me); | |
1211 | if ((oldinfo->number > oldinfo->initial_entries) && | |
1212 | (newinfo->number <= oldinfo->initial_entries)) | |
1213 | module_put(t->me); | |
1214 | ||
1215 | /* Get the old counters. */ | |
1216 | get_counters(oldinfo, counters); | |
1217 | /* Decrease module usage counts and free resource */ | |
1218 | IP6T_ENTRY_ITERATE(oldinfo->entries, oldinfo->size, cleanup_entry,NULL); | |
1219 | vfree(oldinfo); | |
1220 | /* Silent error: too late now. */ | |
1221 | if (copy_to_user(tmp.counters, counters, | |
1222 | sizeof(struct ip6t_counters) * tmp.num_counters) != 0) | |
1223 | ret = -EFAULT; | |
1224 | vfree(counters); | |
1225 | up(&ip6t_mutex); | |
1226 | return ret; | |
1227 | ||
1228 | put_module: | |
1229 | module_put(t->me); | |
1230 | free_newinfo_counters_untrans_unlock: | |
1231 | up(&ip6t_mutex); | |
1232 | free_newinfo_counters_untrans: | |
1233 | IP6T_ENTRY_ITERATE(newinfo->entries, newinfo->size, cleanup_entry,NULL); | |
1234 | free_newinfo_counters: | |
1235 | vfree(counters); | |
1236 | free_newinfo: | |
1237 | vfree(newinfo); | |
1238 | return ret; | |
1239 | } | |
1240 | ||
1241 | /* We're lazy, and add to the first CPU; overflow works its fey magic | |
1242 | * and everything is OK. */ | |
1243 | static inline int | |
1244 | add_counter_to_entry(struct ip6t_entry *e, | |
1245 | const struct ip6t_counters addme[], | |
1246 | unsigned int *i) | |
1247 | { | |
1248 | #if 0 | |
1249 | duprintf("add_counter: Entry %u %lu/%lu + %lu/%lu\n", | |
1250 | *i, | |
1251 | (long unsigned int)e->counters.pcnt, | |
1252 | (long unsigned int)e->counters.bcnt, | |
1253 | (long unsigned int)addme[*i].pcnt, | |
1254 | (long unsigned int)addme[*i].bcnt); | |
1255 | #endif | |
1256 | ||
1257 | ADD_COUNTER(e->counters, addme[*i].bcnt, addme[*i].pcnt); | |
1258 | ||
1259 | (*i)++; | |
1260 | return 0; | |
1261 | } | |
1262 | ||
1263 | static int | |
1264 | do_add_counters(void __user *user, unsigned int len) | |
1265 | { | |
1266 | unsigned int i; | |
1267 | struct ip6t_counters_info tmp, *paddc; | |
1268 | struct ip6t_table *t; | |
1269 | int ret; | |
1270 | ||
1271 | if (copy_from_user(&tmp, user, sizeof(tmp)) != 0) | |
1272 | return -EFAULT; | |
1273 | ||
1274 | if (len != sizeof(tmp) + tmp.num_counters*sizeof(struct ip6t_counters)) | |
1275 | return -EINVAL; | |
1276 | ||
1277 | paddc = vmalloc(len); | |
1278 | if (!paddc) | |
1279 | return -ENOMEM; | |
1280 | ||
1281 | if (copy_from_user(paddc, user, len) != 0) { | |
1282 | ret = -EFAULT; | |
1283 | goto free; | |
1284 | } | |
1285 | ||
1286 | t = ip6t_find_table_lock(tmp.name, &ret, &ip6t_mutex); | |
1287 | if (!t) | |
1288 | goto free; | |
1289 | ||
1290 | write_lock_bh(&t->lock); | |
1291 | if (t->private->number != paddc->num_counters) { | |
1292 | ret = -EINVAL; | |
1293 | goto unlock_up_free; | |
1294 | } | |
1295 | ||
1296 | i = 0; | |
1297 | IP6T_ENTRY_ITERATE(t->private->entries, | |
1298 | t->private->size, | |
1299 | add_counter_to_entry, | |
1300 | paddc->counters, | |
1301 | &i); | |
1302 | unlock_up_free: | |
1303 | write_unlock_bh(&t->lock); | |
1304 | up(&ip6t_mutex); | |
1305 | free: | |
1306 | vfree(paddc); | |
1307 | ||
1308 | return ret; | |
1309 | } | |
1310 | ||
1311 | static int | |
1312 | do_ip6t_set_ctl(struct sock *sk, int cmd, void __user *user, unsigned int len) | |
1313 | { | |
1314 | int ret; | |
1315 | ||
1316 | if (!capable(CAP_NET_ADMIN)) | |
1317 | return -EPERM; | |
1318 | ||
1319 | switch (cmd) { | |
1320 | case IP6T_SO_SET_REPLACE: | |
1321 | ret = do_replace(user, len); | |
1322 | break; | |
1323 | ||
1324 | case IP6T_SO_SET_ADD_COUNTERS: | |
1325 | ret = do_add_counters(user, len); | |
1326 | break; | |
1327 | ||
1328 | default: | |
1329 | duprintf("do_ip6t_set_ctl: unknown request %i\n", cmd); | |
1330 | ret = -EINVAL; | |
1331 | } | |
1332 | ||
1333 | return ret; | |
1334 | } | |
1335 | ||
1336 | static int | |
1337 | do_ip6t_get_ctl(struct sock *sk, int cmd, void __user *user, int *len) | |
1338 | { | |
1339 | int ret; | |
1340 | ||
1341 | if (!capable(CAP_NET_ADMIN)) | |
1342 | return -EPERM; | |
1343 | ||
1344 | switch (cmd) { | |
1345 | case IP6T_SO_GET_INFO: { | |
1346 | char name[IP6T_TABLE_MAXNAMELEN]; | |
1347 | struct ip6t_table *t; | |
1348 | ||
1349 | if (*len != sizeof(struct ip6t_getinfo)) { | |
1350 | duprintf("length %u != %u\n", *len, | |
1351 | sizeof(struct ip6t_getinfo)); | |
1352 | ret = -EINVAL; | |
1353 | break; | |
1354 | } | |
1355 | ||
1356 | if (copy_from_user(name, user, sizeof(name)) != 0) { | |
1357 | ret = -EFAULT; | |
1358 | break; | |
1359 | } | |
1360 | name[IP6T_TABLE_MAXNAMELEN-1] = '\0'; | |
1361 | t = ip6t_find_table_lock(name, &ret, &ip6t_mutex); | |
1362 | if (t) { | |
1363 | struct ip6t_getinfo info; | |
1364 | ||
1365 | info.valid_hooks = t->valid_hooks; | |
1366 | memcpy(info.hook_entry, t->private->hook_entry, | |
1367 | sizeof(info.hook_entry)); | |
1368 | memcpy(info.underflow, t->private->underflow, | |
1369 | sizeof(info.underflow)); | |
1370 | info.num_entries = t->private->number; | |
1371 | info.size = t->private->size; | |
1372 | memcpy(info.name, name, sizeof(info.name)); | |
1373 | ||
1374 | if (copy_to_user(user, &info, *len) != 0) | |
1375 | ret = -EFAULT; | |
1376 | else | |
1377 | ret = 0; | |
1378 | ||
1379 | up(&ip6t_mutex); | |
1380 | } | |
1381 | } | |
1382 | break; | |
1383 | ||
1384 | case IP6T_SO_GET_ENTRIES: { | |
1385 | struct ip6t_get_entries get; | |
1386 | ||
1387 | if (*len < sizeof(get)) { | |
1388 | duprintf("get_entries: %u < %u\n", *len, sizeof(get)); | |
1389 | ret = -EINVAL; | |
1390 | } else if (copy_from_user(&get, user, sizeof(get)) != 0) { | |
1391 | ret = -EFAULT; | |
1392 | } else if (*len != sizeof(struct ip6t_get_entries) + get.size) { | |
1393 | duprintf("get_entries: %u != %u\n", *len, | |
1394 | sizeof(struct ip6t_get_entries) + get.size); | |
1395 | ret = -EINVAL; | |
1396 | } else | |
1397 | ret = get_entries(&get, user); | |
1398 | break; | |
1399 | } | |
1400 | ||
1401 | default: | |
1402 | duprintf("do_ip6t_get_ctl: unknown request %i\n", cmd); | |
1403 | ret = -EINVAL; | |
1404 | } | |
1405 | ||
1406 | return ret; | |
1407 | } | |
1408 | ||
1409 | /* Registration hooks for targets. */ | |
1410 | int | |
1411 | ip6t_register_target(struct ip6t_target *target) | |
1412 | { | |
1413 | int ret; | |
1414 | ||
1415 | ret = down_interruptible(&ip6t_mutex); | |
1416 | if (ret != 0) | |
1417 | return ret; | |
1418 | ||
1419 | if (!list_named_insert(&ip6t_target, target)) { | |
1420 | duprintf("ip6t_register_target: `%s' already in list!\n", | |
1421 | target->name); | |
1422 | ret = -EINVAL; | |
1423 | } | |
1424 | up(&ip6t_mutex); | |
1425 | return ret; | |
1426 | } | |
1427 | ||
1428 | void | |
1429 | ip6t_unregister_target(struct ip6t_target *target) | |
1430 | { | |
1431 | down(&ip6t_mutex); | |
1432 | LIST_DELETE(&ip6t_target, target); | |
1433 | up(&ip6t_mutex); | |
1434 | } | |
1435 | ||
1436 | int | |
1437 | ip6t_register_match(struct ip6t_match *match) | |
1438 | { | |
1439 | int ret; | |
1440 | ||
1441 | ret = down_interruptible(&ip6t_mutex); | |
1442 | if (ret != 0) | |
1443 | return ret; | |
1444 | ||
1445 | if (!list_named_insert(&ip6t_match, match)) { | |
1446 | duprintf("ip6t_register_match: `%s' already in list!\n", | |
1447 | match->name); | |
1448 | ret = -EINVAL; | |
1449 | } | |
1450 | up(&ip6t_mutex); | |
1451 | ||
1452 | return ret; | |
1453 | } | |
1454 | ||
1455 | void | |
1456 | ip6t_unregister_match(struct ip6t_match *match) | |
1457 | { | |
1458 | down(&ip6t_mutex); | |
1459 | LIST_DELETE(&ip6t_match, match); | |
1460 | up(&ip6t_mutex); | |
1461 | } | |
1462 | ||
1463 | int ip6t_register_table(struct ip6t_table *table, | |
1464 | const struct ip6t_replace *repl) | |
1465 | { | |
1466 | int ret; | |
1467 | struct ip6t_table_info *newinfo; | |
1468 | static struct ip6t_table_info bootstrap | |
1469 | = { 0, 0, 0, { 0 }, { 0 }, { } }; | |
1470 | ||
1471 | newinfo = vmalloc(sizeof(struct ip6t_table_info) | |
1472 | + SMP_ALIGN(repl->size) * num_possible_cpus()); | |
1473 | if (!newinfo) | |
1474 | return -ENOMEM; | |
1475 | ||
1476 | memcpy(newinfo->entries, repl->entries, repl->size); | |
1477 | ||
1478 | ret = translate_table(table->name, table->valid_hooks, | |
1479 | newinfo, repl->size, | |
1480 | repl->num_entries, | |
1481 | repl->hook_entry, | |
1482 | repl->underflow); | |
1483 | if (ret != 0) { | |
1484 | vfree(newinfo); | |
1485 | return ret; | |
1486 | } | |
1487 | ||
1488 | ret = down_interruptible(&ip6t_mutex); | |
1489 | if (ret != 0) { | |
1490 | vfree(newinfo); | |
1491 | return ret; | |
1492 | } | |
1493 | ||
1494 | /* Don't autoload: we'd eat our tail... */ | |
1495 | if (list_named_find(&ip6t_tables, table->name)) { | |
1496 | ret = -EEXIST; | |
1497 | goto free_unlock; | |
1498 | } | |
1499 | ||
1500 | /* Simplifies replace_table code. */ | |
1501 | table->private = &bootstrap; | |
1502 | if (!replace_table(table, 0, newinfo, &ret)) | |
1503 | goto free_unlock; | |
1504 | ||
1505 | duprintf("table->private->number = %u\n", | |
1506 | table->private->number); | |
1507 | ||
1508 | /* save number of initial entries */ | |
1509 | table->private->initial_entries = table->private->number; | |
1510 | ||
1511 | rwlock_init(&table->lock); | |
1512 | list_prepend(&ip6t_tables, table); | |
1513 | ||
1514 | unlock: | |
1515 | up(&ip6t_mutex); | |
1516 | return ret; | |
1517 | ||
1518 | free_unlock: | |
1519 | vfree(newinfo); | |
1520 | goto unlock; | |
1521 | } | |
1522 | ||
1523 | void ip6t_unregister_table(struct ip6t_table *table) | |
1524 | { | |
1525 | down(&ip6t_mutex); | |
1526 | LIST_DELETE(&ip6t_tables, table); | |
1527 | up(&ip6t_mutex); | |
1528 | ||
1529 | /* Decrease module usage counts and free resources */ | |
1530 | IP6T_ENTRY_ITERATE(table->private->entries, table->private->size, | |
1531 | cleanup_entry, NULL); | |
1532 | vfree(table->private); | |
1533 | } | |
1534 | ||
1535 | /* Returns 1 if the port is matched by the range, 0 otherwise */ | |
1536 | static inline int | |
1537 | port_match(u_int16_t min, u_int16_t max, u_int16_t port, int invert) | |
1538 | { | |
1539 | int ret; | |
1540 | ||
1541 | ret = (port >= min && port <= max) ^ invert; | |
1542 | return ret; | |
1543 | } | |
1544 | ||
1545 | static int | |
1546 | tcp_find_option(u_int8_t option, | |
1547 | const struct sk_buff *skb, | |
1548 | unsigned int tcpoff, | |
1549 | unsigned int optlen, | |
1550 | int invert, | |
1551 | int *hotdrop) | |
1552 | { | |
1553 | /* tcp.doff is only 4 bits, ie. max 15 * 4 bytes */ | |
1554 | u_int8_t _opt[60 - sizeof(struct tcphdr)], *op; | |
1555 | unsigned int i; | |
1556 | ||
1557 | duprintf("tcp_match: finding option\n"); | |
1558 | if (!optlen) | |
1559 | return invert; | |
1560 | /* If we don't have the whole header, drop packet. */ | |
1561 | op = skb_header_pointer(skb, tcpoff + sizeof(struct tcphdr), optlen, | |
1562 | _opt); | |
1563 | if (op == NULL) { | |
1564 | *hotdrop = 1; | |
1565 | return 0; | |
1566 | } | |
1567 | ||
1568 | for (i = 0; i < optlen; ) { | |
1569 | if (op[i] == option) return !invert; | |
1570 | if (op[i] < 2) i++; | |
1571 | else i += op[i+1]?:1; | |
1572 | } | |
1573 | ||
1574 | return invert; | |
1575 | } | |
1576 | ||
1577 | static int | |
1578 | tcp_match(const struct sk_buff *skb, | |
1579 | const struct net_device *in, | |
1580 | const struct net_device *out, | |
1581 | const void *matchinfo, | |
1582 | int offset, | |
1583 | unsigned int protoff, | |
1584 | int *hotdrop) | |
1585 | { | |
1586 | struct tcphdr _tcph, *th; | |
1587 | const struct ip6t_tcp *tcpinfo = matchinfo; | |
1588 | ||
1589 | if (offset) { | |
1590 | /* To quote Alan: | |
1591 | ||
1592 | Don't allow a fragment of TCP 8 bytes in. Nobody normal | |
1593 | causes this. Its a cracker trying to break in by doing a | |
1594 | flag overwrite to pass the direction checks. | |
1595 | */ | |
1596 | if (offset == 1) { | |
1597 | duprintf("Dropping evil TCP offset=1 frag.\n"); | |
1598 | *hotdrop = 1; | |
1599 | } | |
1600 | /* Must not be a fragment. */ | |
1601 | return 0; | |
1602 | } | |
1603 | ||
1604 | #define FWINVTCP(bool,invflg) ((bool) ^ !!(tcpinfo->invflags & invflg)) | |
1605 | ||
1606 | th = skb_header_pointer(skb, protoff, sizeof(_tcph), &_tcph); | |
1607 | if (th == NULL) { | |
1608 | /* We've been asked to examine this packet, and we | |
1609 | can't. Hence, no choice but to drop. */ | |
1610 | duprintf("Dropping evil TCP offset=0 tinygram.\n"); | |
1611 | *hotdrop = 1; | |
1612 | return 0; | |
1613 | } | |
1614 | ||
1615 | if (!port_match(tcpinfo->spts[0], tcpinfo->spts[1], | |
1616 | ntohs(th->source), | |
1617 | !!(tcpinfo->invflags & IP6T_TCP_INV_SRCPT))) | |
1618 | return 0; | |
1619 | if (!port_match(tcpinfo->dpts[0], tcpinfo->dpts[1], | |
1620 | ntohs(th->dest), | |
1621 | !!(tcpinfo->invflags & IP6T_TCP_INV_DSTPT))) | |
1622 | return 0; | |
1623 | if (!FWINVTCP((((unsigned char *)th)[13] & tcpinfo->flg_mask) | |
1624 | == tcpinfo->flg_cmp, | |
1625 | IP6T_TCP_INV_FLAGS)) | |
1626 | return 0; | |
1627 | if (tcpinfo->option) { | |
1628 | if (th->doff * 4 < sizeof(_tcph)) { | |
1629 | *hotdrop = 1; | |
1630 | return 0; | |
1631 | } | |
1632 | if (!tcp_find_option(tcpinfo->option, skb, protoff, | |
1633 | th->doff*4 - sizeof(*th), | |
1634 | tcpinfo->invflags & IP6T_TCP_INV_OPTION, | |
1635 | hotdrop)) | |
1636 | return 0; | |
1637 | } | |
1638 | return 1; | |
1639 | } | |
1640 | ||
1641 | /* Called when user tries to insert an entry of this type. */ | |
1642 | static int | |
1643 | tcp_checkentry(const char *tablename, | |
1644 | const struct ip6t_ip6 *ipv6, | |
1645 | void *matchinfo, | |
1646 | unsigned int matchsize, | |
1647 | unsigned int hook_mask) | |
1648 | { | |
1649 | const struct ip6t_tcp *tcpinfo = matchinfo; | |
1650 | ||
1651 | /* Must specify proto == TCP, and no unknown invflags */ | |
1652 | return ipv6->proto == IPPROTO_TCP | |
1653 | && !(ipv6->invflags & IP6T_INV_PROTO) | |
1654 | && matchsize == IP6T_ALIGN(sizeof(struct ip6t_tcp)) | |
1655 | && !(tcpinfo->invflags & ~IP6T_TCP_INV_MASK); | |
1656 | } | |
1657 | ||
1658 | static int | |
1659 | udp_match(const struct sk_buff *skb, | |
1660 | const struct net_device *in, | |
1661 | const struct net_device *out, | |
1662 | const void *matchinfo, | |
1663 | int offset, | |
1664 | unsigned int protoff, | |
1665 | int *hotdrop) | |
1666 | { | |
1667 | struct udphdr _udph, *uh; | |
1668 | const struct ip6t_udp *udpinfo = matchinfo; | |
1669 | ||
1670 | /* Must not be a fragment. */ | |
1671 | if (offset) | |
1672 | return 0; | |
1673 | ||
1674 | uh = skb_header_pointer(skb, protoff, sizeof(_udph), &_udph); | |
1675 | if (uh == NULL) { | |
1676 | /* We've been asked to examine this packet, and we | |
1677 | can't. Hence, no choice but to drop. */ | |
1678 | duprintf("Dropping evil UDP tinygram.\n"); | |
1679 | *hotdrop = 1; | |
1680 | return 0; | |
1681 | } | |
1682 | ||
1683 | return port_match(udpinfo->spts[0], udpinfo->spts[1], | |
1684 | ntohs(uh->source), | |
1685 | !!(udpinfo->invflags & IP6T_UDP_INV_SRCPT)) | |
1686 | && port_match(udpinfo->dpts[0], udpinfo->dpts[1], | |
1687 | ntohs(uh->dest), | |
1688 | !!(udpinfo->invflags & IP6T_UDP_INV_DSTPT)); | |
1689 | } | |
1690 | ||
1691 | /* Called when user tries to insert an entry of this type. */ | |
1692 | static int | |
1693 | udp_checkentry(const char *tablename, | |
1694 | const struct ip6t_ip6 *ipv6, | |
1695 | void *matchinfo, | |
1696 | unsigned int matchinfosize, | |
1697 | unsigned int hook_mask) | |
1698 | { | |
1699 | const struct ip6t_udp *udpinfo = matchinfo; | |
1700 | ||
1701 | /* Must specify proto == UDP, and no unknown invflags */ | |
1702 | if (ipv6->proto != IPPROTO_UDP || (ipv6->invflags & IP6T_INV_PROTO)) { | |
1703 | duprintf("ip6t_udp: Protocol %u != %u\n", ipv6->proto, | |
1704 | IPPROTO_UDP); | |
1705 | return 0; | |
1706 | } | |
1707 | if (matchinfosize != IP6T_ALIGN(sizeof(struct ip6t_udp))) { | |
1708 | duprintf("ip6t_udp: matchsize %u != %u\n", | |
1709 | matchinfosize, IP6T_ALIGN(sizeof(struct ip6t_udp))); | |
1710 | return 0; | |
1711 | } | |
1712 | if (udpinfo->invflags & ~IP6T_UDP_INV_MASK) { | |
1713 | duprintf("ip6t_udp: unknown flags %X\n", | |
1714 | udpinfo->invflags); | |
1715 | return 0; | |
1716 | } | |
1717 | ||
1718 | return 1; | |
1719 | } | |
1720 | ||
1721 | /* Returns 1 if the type and code is matched by the range, 0 otherwise */ | |
1722 | static inline int | |
1723 | icmp6_type_code_match(u_int8_t test_type, u_int8_t min_code, u_int8_t max_code, | |
1724 | u_int8_t type, u_int8_t code, | |
1725 | int invert) | |
1726 | { | |
1727 | return (type == test_type && code >= min_code && code <= max_code) | |
1728 | ^ invert; | |
1729 | } | |
1730 | ||
1731 | static int | |
1732 | icmp6_match(const struct sk_buff *skb, | |
1733 | const struct net_device *in, | |
1734 | const struct net_device *out, | |
1735 | const void *matchinfo, | |
1736 | int offset, | |
1737 | unsigned int protoff, | |
1738 | int *hotdrop) | |
1739 | { | |
1740 | struct icmp6hdr _icmp, *ic; | |
1741 | const struct ip6t_icmp *icmpinfo = matchinfo; | |
1742 | ||
1743 | /* Must not be a fragment. */ | |
1744 | if (offset) | |
1745 | return 0; | |
1746 | ||
1747 | ic = skb_header_pointer(skb, protoff, sizeof(_icmp), &_icmp); | |
1748 | if (ic == NULL) { | |
1749 | /* We've been asked to examine this packet, and we | |
1750 | can't. Hence, no choice but to drop. */ | |
1751 | duprintf("Dropping evil ICMP tinygram.\n"); | |
1752 | *hotdrop = 1; | |
1753 | return 0; | |
1754 | } | |
1755 | ||
1756 | return icmp6_type_code_match(icmpinfo->type, | |
1757 | icmpinfo->code[0], | |
1758 | icmpinfo->code[1], | |
1759 | ic->icmp6_type, ic->icmp6_code, | |
1760 | !!(icmpinfo->invflags&IP6T_ICMP_INV)); | |
1761 | } | |
1762 | ||
1763 | /* Called when user tries to insert an entry of this type. */ | |
1764 | static int | |
1765 | icmp6_checkentry(const char *tablename, | |
1766 | const struct ip6t_ip6 *ipv6, | |
1767 | void *matchinfo, | |
1768 | unsigned int matchsize, | |
1769 | unsigned int hook_mask) | |
1770 | { | |
1771 | const struct ip6t_icmp *icmpinfo = matchinfo; | |
1772 | ||
1773 | /* Must specify proto == ICMP, and no unknown invflags */ | |
1774 | return ipv6->proto == IPPROTO_ICMPV6 | |
1775 | && !(ipv6->invflags & IP6T_INV_PROTO) | |
1776 | && matchsize == IP6T_ALIGN(sizeof(struct ip6t_icmp)) | |
1777 | && !(icmpinfo->invflags & ~IP6T_ICMP_INV); | |
1778 | } | |
1779 | ||
1780 | /* The built-in targets: standard (NULL) and error. */ | |
1781 | static struct ip6t_target ip6t_standard_target = { | |
1782 | .name = IP6T_STANDARD_TARGET, | |
1783 | }; | |
1784 | ||
1785 | static struct ip6t_target ip6t_error_target = { | |
1786 | .name = IP6T_ERROR_TARGET, | |
1787 | .target = ip6t_error, | |
1788 | }; | |
1789 | ||
1790 | static struct nf_sockopt_ops ip6t_sockopts = { | |
1791 | .pf = PF_INET6, | |
1792 | .set_optmin = IP6T_BASE_CTL, | |
1793 | .set_optmax = IP6T_SO_SET_MAX+1, | |
1794 | .set = do_ip6t_set_ctl, | |
1795 | .get_optmin = IP6T_BASE_CTL, | |
1796 | .get_optmax = IP6T_SO_GET_MAX+1, | |
1797 | .get = do_ip6t_get_ctl, | |
1798 | }; | |
1799 | ||
1800 | static struct ip6t_match tcp_matchstruct = { | |
1801 | .name = "tcp", | |
1802 | .match = &tcp_match, | |
1803 | .checkentry = &tcp_checkentry, | |
1804 | }; | |
1805 | ||
1806 | static struct ip6t_match udp_matchstruct = { | |
1807 | .name = "udp", | |
1808 | .match = &udp_match, | |
1809 | .checkentry = &udp_checkentry, | |
1810 | }; | |
1811 | ||
1812 | static struct ip6t_match icmp6_matchstruct = { | |
1813 | .name = "icmp6", | |
1814 | .match = &icmp6_match, | |
1815 | .checkentry = &icmp6_checkentry, | |
1816 | }; | |
1817 | ||
1818 | #ifdef CONFIG_PROC_FS | |
1819 | static inline int print_name(const char *i, | |
1820 | off_t start_offset, char *buffer, int length, | |
1821 | off_t *pos, unsigned int *count) | |
1822 | { | |
1823 | if ((*count)++ >= start_offset) { | |
1824 | unsigned int namelen; | |
1825 | ||
1826 | namelen = sprintf(buffer + *pos, "%s\n", | |
1827 | i + sizeof(struct list_head)); | |
1828 | if (*pos + namelen > length) { | |
1829 | /* Stop iterating */ | |
1830 | return 1; | |
1831 | } | |
1832 | *pos += namelen; | |
1833 | } | |
1834 | return 0; | |
1835 | } | |
1836 | ||
1837 | static inline int print_target(const struct ip6t_target *t, | |
1838 | off_t start_offset, char *buffer, int length, | |
1839 | off_t *pos, unsigned int *count) | |
1840 | { | |
1841 | if (t == &ip6t_standard_target || t == &ip6t_error_target) | |
1842 | return 0; | |
1843 | return print_name((char *)t, start_offset, buffer, length, pos, count); | |
1844 | } | |
1845 | ||
1846 | static int ip6t_get_tables(char *buffer, char **start, off_t offset, int length) | |
1847 | { | |
1848 | off_t pos = 0; | |
1849 | unsigned int count = 0; | |
1850 | ||
1851 | if (down_interruptible(&ip6t_mutex) != 0) | |
1852 | return 0; | |
1853 | ||
1854 | LIST_FIND(&ip6t_tables, print_name, char *, | |
1855 | offset, buffer, length, &pos, &count); | |
1856 | ||
1857 | up(&ip6t_mutex); | |
1858 | ||
1859 | /* `start' hack - see fs/proc/generic.c line ~105 */ | |
1860 | *start=(char *)((unsigned long)count-offset); | |
1861 | return pos; | |
1862 | } | |
1863 | ||
1864 | static int ip6t_get_targets(char *buffer, char **start, off_t offset, int length) | |
1865 | { | |
1866 | off_t pos = 0; | |
1867 | unsigned int count = 0; | |
1868 | ||
1869 | if (down_interruptible(&ip6t_mutex) != 0) | |
1870 | return 0; | |
1871 | ||
1872 | LIST_FIND(&ip6t_target, print_target, struct ip6t_target *, | |
1873 | offset, buffer, length, &pos, &count); | |
1874 | ||
1875 | up(&ip6t_mutex); | |
1876 | ||
1877 | *start = (char *)((unsigned long)count - offset); | |
1878 | return pos; | |
1879 | } | |
1880 | ||
1881 | static int ip6t_get_matches(char *buffer, char **start, off_t offset, int length) | |
1882 | { | |
1883 | off_t pos = 0; | |
1884 | unsigned int count = 0; | |
1885 | ||
1886 | if (down_interruptible(&ip6t_mutex) != 0) | |
1887 | return 0; | |
1888 | ||
1889 | LIST_FIND(&ip6t_match, print_name, char *, | |
1890 | offset, buffer, length, &pos, &count); | |
1891 | ||
1892 | up(&ip6t_mutex); | |
1893 | ||
1894 | *start = (char *)((unsigned long)count - offset); | |
1895 | return pos; | |
1896 | } | |
1897 | ||
1898 | static struct { char *name; get_info_t *get_info; } ip6t_proc_entry[] = | |
1899 | { { "ip6_tables_names", ip6t_get_tables }, | |
1900 | { "ip6_tables_targets", ip6t_get_targets }, | |
1901 | { "ip6_tables_matches", ip6t_get_matches }, | |
1902 | { NULL, NULL} }; | |
1903 | #endif /*CONFIG_PROC_FS*/ | |
1904 | ||
1905 | static int __init init(void) | |
1906 | { | |
1907 | int ret; | |
1908 | ||
1909 | /* Noone else will be downing sem now, so we won't sleep */ | |
1910 | down(&ip6t_mutex); | |
1911 | list_append(&ip6t_target, &ip6t_standard_target); | |
1912 | list_append(&ip6t_target, &ip6t_error_target); | |
1913 | list_append(&ip6t_match, &tcp_matchstruct); | |
1914 | list_append(&ip6t_match, &udp_matchstruct); | |
1915 | list_append(&ip6t_match, &icmp6_matchstruct); | |
1916 | up(&ip6t_mutex); | |
1917 | ||
1918 | /* Register setsockopt */ | |
1919 | ret = nf_register_sockopt(&ip6t_sockopts); | |
1920 | if (ret < 0) { | |
1921 | duprintf("Unable to register sockopts.\n"); | |
1922 | return ret; | |
1923 | } | |
1924 | ||
1925 | #ifdef CONFIG_PROC_FS | |
1926 | { | |
1927 | struct proc_dir_entry *proc; | |
1928 | int i; | |
1929 | ||
1930 | for (i = 0; ip6t_proc_entry[i].name; i++) { | |
1931 | proc = proc_net_create(ip6t_proc_entry[i].name, 0, | |
1932 | ip6t_proc_entry[i].get_info); | |
1933 | if (!proc) { | |
1934 | while (--i >= 0) | |
1935 | proc_net_remove(ip6t_proc_entry[i].name); | |
1936 | nf_unregister_sockopt(&ip6t_sockopts); | |
1937 | return -ENOMEM; | |
1938 | } | |
1939 | proc->owner = THIS_MODULE; | |
1940 | } | |
1941 | } | |
1942 | #endif | |
1943 | ||
1944 | printk("ip6_tables: (C) 2000-2002 Netfilter core team\n"); | |
1945 | return 0; | |
1946 | } | |
1947 | ||
1948 | static void __exit fini(void) | |
1949 | { | |
1950 | nf_unregister_sockopt(&ip6t_sockopts); | |
1951 | #ifdef CONFIG_PROC_FS | |
1952 | { | |
1953 | int i; | |
1954 | for (i = 0; ip6t_proc_entry[i].name; i++) | |
1955 | proc_net_remove(ip6t_proc_entry[i].name); | |
1956 | } | |
1957 | #endif | |
1958 | } | |
1959 | ||
1960 | EXPORT_SYMBOL(ip6t_register_table); | |
1961 | EXPORT_SYMBOL(ip6t_unregister_table); | |
1962 | EXPORT_SYMBOL(ip6t_do_table); | |
1963 | EXPORT_SYMBOL(ip6t_register_match); | |
1964 | EXPORT_SYMBOL(ip6t_unregister_match); | |
1965 | EXPORT_SYMBOL(ip6t_register_target); | |
1966 | EXPORT_SYMBOL(ip6t_unregister_target); | |
1967 | EXPORT_SYMBOL(ip6t_ext_hdr); | |
1968 | ||
1969 | module_init(init); | |
1970 | module_exit(fini); |