Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * Packet matching code. | |
3 | * | |
4 | * Copyright (C) 1999 Paul `Rusty' Russell & Michael J. Neuling | |
6b7d31fc | 5 | * Copyright (C) 2000-2005 Netfilter Core Team <coreteam@netfilter.org> |
1da177e4 LT |
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> | |
14c85021 | 18 | #include <linux/in.h> |
1da177e4 LT |
19 | #include <linux/skbuff.h> |
20 | #include <linux/kmod.h> | |
21 | #include <linux/vmalloc.h> | |
22 | #include <linux/netdevice.h> | |
23 | #include <linux/module.h> | |
24 | #include <linux/tcp.h> | |
25 | #include <linux/udp.h> | |
26 | #include <linux/icmpv6.h> | |
1da177e4 LT |
27 | #include <net/ipv6.h> |
28 | #include <asm/uaccess.h> | |
29 | #include <asm/semaphore.h> | |
30 | #include <linux/proc_fs.h> | |
c8923c6b | 31 | #include <linux/cpumask.h> |
1da177e4 LT |
32 | |
33 | #include <linux/netfilter_ipv6/ip6_tables.h> | |
34 | ||
35 | MODULE_LICENSE("GPL"); | |
36 | MODULE_AUTHOR("Netfilter Core Team <coreteam@netfilter.org>"); | |
37 | MODULE_DESCRIPTION("IPv6 packet filter"); | |
38 | ||
39 | #define IPV6_HDR_LEN (sizeof(struct ipv6hdr)) | |
40 | #define IPV6_OPTHDR_LEN (sizeof(struct ipv6_opt_hdr)) | |
41 | ||
42 | /*#define DEBUG_IP_FIREWALL*/ | |
43 | /*#define DEBUG_ALLOW_ALL*/ /* Useful for remote debugging */ | |
44 | /*#define DEBUG_IP_FIREWALL_USER*/ | |
45 | ||
46 | #ifdef DEBUG_IP_FIREWALL | |
47 | #define dprintf(format, args...) printk(format , ## args) | |
48 | #else | |
49 | #define dprintf(format, args...) | |
50 | #endif | |
51 | ||
52 | #ifdef DEBUG_IP_FIREWALL_USER | |
53 | #define duprintf(format, args...) printk(format , ## args) | |
54 | #else | |
55 | #define duprintf(format, args...) | |
56 | #endif | |
57 | ||
58 | #ifdef CONFIG_NETFILTER_DEBUG | |
59 | #define IP_NF_ASSERT(x) \ | |
60 | do { \ | |
61 | if (!(x)) \ | |
62 | printk("IP_NF_ASSERT: %s:%s:%u\n", \ | |
63 | __FUNCTION__, __FILE__, __LINE__); \ | |
64 | } while(0) | |
65 | #else | |
66 | #define IP_NF_ASSERT(x) | |
67 | #endif | |
68 | #define SMP_ALIGN(x) (((x) + SMP_CACHE_BYTES-1) & ~(SMP_CACHE_BYTES-1)) | |
69 | ||
70 | static DECLARE_MUTEX(ip6t_mutex); | |
71 | ||
72 | /* Must have mutex */ | |
73 | #define ASSERT_READ_LOCK(x) IP_NF_ASSERT(down_trylock(&ip6t_mutex) != 0) | |
74 | #define ASSERT_WRITE_LOCK(x) IP_NF_ASSERT(down_trylock(&ip6t_mutex) != 0) | |
1da177e4 LT |
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 | ||
6b7d31fc | 83 | /* |
1da177e4 | 84 | We keep a set of rules for each CPU, so we can avoid write-locking |
6b7d31fc HW |
85 | them in the softirq when updating the counters and therefore |
86 | only need to read-lock in the softirq; doing a write_lock_bh() in user | |
87 | context stops packets coming through and allows user context to read | |
88 | the counters or update the rules. | |
1da177e4 | 89 | |
1da177e4 LT |
90 | Hence the start of any table is given by get_table() below. */ |
91 | ||
92 | /* The table itself */ | |
93 | struct ip6t_table_info | |
94 | { | |
95 | /* Size per table */ | |
96 | unsigned int size; | |
97 | /* Number of entries: FIXME. --RR */ | |
98 | unsigned int number; | |
99 | /* Initial number of entries. Needed for module usage count */ | |
100 | unsigned int initial_entries; | |
101 | ||
102 | /* Entry points and underflows */ | |
103 | unsigned int hook_entry[NF_IP6_NUMHOOKS]; | |
104 | unsigned int underflow[NF_IP6_NUMHOOKS]; | |
105 | ||
106 | /* ip6t_entry tables: one per CPU */ | |
31836064 | 107 | void *entries[NR_CPUS]; |
1da177e4 LT |
108 | }; |
109 | ||
110 | static LIST_HEAD(ip6t_target); | |
111 | static LIST_HEAD(ip6t_match); | |
112 | static LIST_HEAD(ip6t_tables); | |
31836064 | 113 | #define SET_COUNTER(c,b,p) do { (c).bcnt = (b); (c).pcnt = (p); } while(0) |
1da177e4 LT |
114 | #define ADD_COUNTER(c,b,p) do { (c).bcnt += (b); (c).pcnt += (p); } while(0) |
115 | ||
1da177e4 LT |
116 | #if 0 |
117 | #define down(x) do { printk("DOWN:%u:" #x "\n", __LINE__); down(x); } while(0) | |
118 | #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; }) | |
119 | #define up(x) do { printk("UP:%u:" #x "\n", __LINE__); up(x); } while(0) | |
120 | #endif | |
121 | ||
22dea562 PM |
122 | int |
123 | ip6_masked_addrcmp(const struct in6_addr *addr1, const struct in6_addr *mask, | |
124 | const struct in6_addr *addr2) | |
1da177e4 LT |
125 | { |
126 | int i; | |
127 | for( i = 0; i < 16; i++){ | |
22dea562 PM |
128 | if((addr1->s6_addr[i] & mask->s6_addr[i]) != |
129 | (addr2->s6_addr[i] & mask->s6_addr[i])) | |
1da177e4 LT |
130 | return 1; |
131 | } | |
132 | return 0; | |
133 | } | |
134 | ||
135 | /* Check for an extension */ | |
136 | int | |
137 | ip6t_ext_hdr(u8 nexthdr) | |
138 | { | |
139 | return ( (nexthdr == IPPROTO_HOPOPTS) || | |
140 | (nexthdr == IPPROTO_ROUTING) || | |
141 | (nexthdr == IPPROTO_FRAGMENT) || | |
142 | (nexthdr == IPPROTO_ESP) || | |
143 | (nexthdr == IPPROTO_AH) || | |
144 | (nexthdr == IPPROTO_NONE) || | |
145 | (nexthdr == IPPROTO_DSTOPTS) ); | |
146 | } | |
147 | ||
148 | /* Returns whether matches rule or not. */ | |
149 | static inline int | |
150 | ip6_packet_match(const struct sk_buff *skb, | |
151 | const char *indev, | |
152 | const char *outdev, | |
153 | const struct ip6t_ip6 *ip6info, | |
154 | unsigned int *protoff, | |
155 | int *fragoff) | |
156 | { | |
157 | size_t i; | |
158 | unsigned long ret; | |
159 | const struct ipv6hdr *ipv6 = skb->nh.ipv6h; | |
160 | ||
161 | #define FWINV(bool,invflg) ((bool) ^ !!(ip6info->invflags & invflg)) | |
162 | ||
22dea562 PM |
163 | if (FWINV(ip6_masked_addrcmp(&ipv6->saddr, &ip6info->smsk, |
164 | &ip6info->src), IP6T_INV_SRCIP) | |
165 | || FWINV(ip6_masked_addrcmp(&ipv6->daddr, &ip6info->dmsk, | |
166 | &ip6info->dst), IP6T_INV_DSTIP)) { | |
1da177e4 LT |
167 | dprintf("Source or dest mismatch.\n"); |
168 | /* | |
169 | dprintf("SRC: %u. Mask: %u. Target: %u.%s\n", ip->saddr, | |
170 | ipinfo->smsk.s_addr, ipinfo->src.s_addr, | |
171 | ipinfo->invflags & IP6T_INV_SRCIP ? " (INV)" : ""); | |
172 | dprintf("DST: %u. Mask: %u. Target: %u.%s\n", ip->daddr, | |
173 | ipinfo->dmsk.s_addr, ipinfo->dst.s_addr, | |
174 | ipinfo->invflags & IP6T_INV_DSTIP ? " (INV)" : "");*/ | |
175 | return 0; | |
176 | } | |
177 | ||
178 | /* Look for ifname matches; this should unroll nicely. */ | |
179 | for (i = 0, ret = 0; i < IFNAMSIZ/sizeof(unsigned long); i++) { | |
180 | ret |= (((const unsigned long *)indev)[i] | |
181 | ^ ((const unsigned long *)ip6info->iniface)[i]) | |
182 | & ((const unsigned long *)ip6info->iniface_mask)[i]; | |
183 | } | |
184 | ||
185 | if (FWINV(ret != 0, IP6T_INV_VIA_IN)) { | |
186 | dprintf("VIA in mismatch (%s vs %s).%s\n", | |
187 | indev, ip6info->iniface, | |
188 | ip6info->invflags&IP6T_INV_VIA_IN ?" (INV)":""); | |
189 | return 0; | |
190 | } | |
191 | ||
192 | for (i = 0, ret = 0; i < IFNAMSIZ/sizeof(unsigned long); i++) { | |
193 | ret |= (((const unsigned long *)outdev)[i] | |
194 | ^ ((const unsigned long *)ip6info->outiface)[i]) | |
195 | & ((const unsigned long *)ip6info->outiface_mask)[i]; | |
196 | } | |
197 | ||
198 | if (FWINV(ret != 0, IP6T_INV_VIA_OUT)) { | |
199 | dprintf("VIA out mismatch (%s vs %s).%s\n", | |
200 | outdev, ip6info->outiface, | |
201 | ip6info->invflags&IP6T_INV_VIA_OUT ?" (INV)":""); | |
202 | return 0; | |
203 | } | |
204 | ||
205 | /* ... might want to do something with class and flowlabel here ... */ | |
206 | ||
207 | /* look for the desired protocol header */ | |
208 | if((ip6info->flags & IP6T_F_PROTO)) { | |
b777e0ce PM |
209 | int protohdr; |
210 | unsigned short _frag_off; | |
1da177e4 | 211 | |
b777e0ce PM |
212 | protohdr = ipv6_find_hdr(skb, protoff, -1, &_frag_off); |
213 | if (protohdr < 0) | |
214 | return 0; | |
1da177e4 | 215 | |
b777e0ce | 216 | *fragoff = _frag_off; |
1da177e4 LT |
217 | |
218 | dprintf("Packet protocol %hi ?= %s%hi.\n", | |
b777e0ce | 219 | protohdr, |
1da177e4 LT |
220 | ip6info->invflags & IP6T_INV_PROTO ? "!":"", |
221 | ip6info->proto); | |
222 | ||
b777e0ce | 223 | if (ip6info->proto == protohdr) { |
1da177e4 LT |
224 | if(ip6info->invflags & IP6T_INV_PROTO) { |
225 | return 0; | |
226 | } | |
227 | return 1; | |
228 | } | |
229 | ||
230 | /* We need match for the '-p all', too! */ | |
231 | if ((ip6info->proto != 0) && | |
232 | !(ip6info->invflags & IP6T_INV_PROTO)) | |
233 | return 0; | |
234 | } | |
235 | return 1; | |
236 | } | |
237 | ||
238 | /* should be ip6 safe */ | |
239 | static inline int | |
240 | ip6_checkentry(const struct ip6t_ip6 *ipv6) | |
241 | { | |
242 | if (ipv6->flags & ~IP6T_F_MASK) { | |
243 | duprintf("Unknown flag bits set: %08X\n", | |
244 | ipv6->flags & ~IP6T_F_MASK); | |
245 | return 0; | |
246 | } | |
247 | if (ipv6->invflags & ~IP6T_INV_MASK) { | |
248 | duprintf("Unknown invflag bits set: %08X\n", | |
249 | ipv6->invflags & ~IP6T_INV_MASK); | |
250 | return 0; | |
251 | } | |
252 | return 1; | |
253 | } | |
254 | ||
255 | static unsigned int | |
256 | ip6t_error(struct sk_buff **pskb, | |
257 | const struct net_device *in, | |
258 | const struct net_device *out, | |
259 | unsigned int hooknum, | |
260 | const void *targinfo, | |
261 | void *userinfo) | |
262 | { | |
263 | if (net_ratelimit()) | |
264 | printk("ip6_tables: error: `%s'\n", (char *)targinfo); | |
265 | ||
266 | return NF_DROP; | |
267 | } | |
268 | ||
269 | static inline | |
270 | int do_match(struct ip6t_entry_match *m, | |
271 | const struct sk_buff *skb, | |
272 | const struct net_device *in, | |
273 | const struct net_device *out, | |
274 | int offset, | |
275 | unsigned int protoff, | |
276 | int *hotdrop) | |
277 | { | |
278 | /* Stop iteration if it doesn't match */ | |
279 | if (!m->u.kernel.match->match(skb, in, out, m->data, | |
280 | offset, protoff, hotdrop)) | |
281 | return 1; | |
282 | else | |
283 | return 0; | |
284 | } | |
285 | ||
286 | static inline struct ip6t_entry * | |
287 | get_entry(void *base, unsigned int offset) | |
288 | { | |
289 | return (struct ip6t_entry *)(base + offset); | |
290 | } | |
291 | ||
292 | /* Returns one of the generic firewall policies, like NF_ACCEPT. */ | |
293 | unsigned int | |
294 | ip6t_do_table(struct sk_buff **pskb, | |
295 | unsigned int hook, | |
296 | const struct net_device *in, | |
297 | const struct net_device *out, | |
298 | struct ip6t_table *table, | |
299 | void *userdata) | |
300 | { | |
6b7d31fc | 301 | static const char nulldevname[IFNAMSIZ] __attribute__((aligned(sizeof(long)))); |
1da177e4 LT |
302 | int offset = 0; |
303 | unsigned int protoff = 0; | |
304 | int hotdrop = 0; | |
305 | /* Initializing verdict to NF_DROP keeps gcc happy. */ | |
306 | unsigned int verdict = NF_DROP; | |
307 | const char *indev, *outdev; | |
308 | void *table_base; | |
309 | struct ip6t_entry *e, *back; | |
310 | ||
311 | /* Initialization */ | |
312 | indev = in ? in->name : nulldevname; | |
313 | outdev = out ? out->name : nulldevname; | |
1da177e4 LT |
314 | /* We handle fragments by dealing with the first fragment as |
315 | * if it was a normal packet. All other fragments are treated | |
316 | * normally, except that they will NEVER match rules that ask | |
317 | * things we don't know, ie. tcp syn flag or ports). If the | |
318 | * rule is also a fragment-specific rule, non-fragments won't | |
319 | * match it. */ | |
320 | ||
321 | read_lock_bh(&table->lock); | |
322 | IP_NF_ASSERT(table->valid_hooks & (1 << hook)); | |
31836064 | 323 | table_base = (void *)table->private->entries[smp_processor_id()]; |
1da177e4 LT |
324 | e = get_entry(table_base, table->private->hook_entry[hook]); |
325 | ||
326 | #ifdef CONFIG_NETFILTER_DEBUG | |
327 | /* Check noone else using our table */ | |
328 | if (((struct ip6t_entry *)table_base)->comefrom != 0xdead57ac | |
329 | && ((struct ip6t_entry *)table_base)->comefrom != 0xeeeeeeec) { | |
330 | printk("ASSERT: CPU #%u, %s comefrom(%p) = %X\n", | |
331 | smp_processor_id(), | |
332 | table->name, | |
333 | &((struct ip6t_entry *)table_base)->comefrom, | |
334 | ((struct ip6t_entry *)table_base)->comefrom); | |
335 | } | |
336 | ((struct ip6t_entry *)table_base)->comefrom = 0x57acc001; | |
337 | #endif | |
338 | ||
339 | /* For return from builtin chain */ | |
340 | back = get_entry(table_base, table->private->underflow[hook]); | |
341 | ||
342 | do { | |
343 | IP_NF_ASSERT(e); | |
344 | IP_NF_ASSERT(back); | |
1da177e4 LT |
345 | if (ip6_packet_match(*pskb, indev, outdev, &e->ipv6, |
346 | &protoff, &offset)) { | |
347 | struct ip6t_entry_target *t; | |
348 | ||
349 | if (IP6T_MATCH_ITERATE(e, do_match, | |
350 | *pskb, in, out, | |
351 | offset, protoff, &hotdrop) != 0) | |
352 | goto no_match; | |
353 | ||
354 | ADD_COUNTER(e->counters, | |
355 | ntohs((*pskb)->nh.ipv6h->payload_len) | |
356 | + IPV6_HDR_LEN, | |
357 | 1); | |
358 | ||
359 | t = ip6t_get_target(e); | |
360 | IP_NF_ASSERT(t->u.kernel.target); | |
361 | /* Standard target? */ | |
362 | if (!t->u.kernel.target->target) { | |
363 | int v; | |
364 | ||
365 | v = ((struct ip6t_standard_target *)t)->verdict; | |
366 | if (v < 0) { | |
367 | /* Pop from stack? */ | |
368 | if (v != IP6T_RETURN) { | |
369 | verdict = (unsigned)(-v) - 1; | |
370 | break; | |
371 | } | |
372 | e = back; | |
373 | back = get_entry(table_base, | |
374 | back->comefrom); | |
375 | continue; | |
376 | } | |
05465343 PM |
377 | if (table_base + v != (void *)e + e->next_offset |
378 | && !(e->ipv6.flags & IP6T_F_GOTO)) { | |
1da177e4 LT |
379 | /* Save old back ptr in next entry */ |
380 | struct ip6t_entry *next | |
381 | = (void *)e + e->next_offset; | |
382 | next->comefrom | |
383 | = (void *)back - table_base; | |
384 | /* set back pointer to next entry */ | |
385 | back = next; | |
386 | } | |
387 | ||
388 | e = get_entry(table_base, v); | |
389 | } else { | |
390 | /* Targets which reenter must return | |
391 | abs. verdicts */ | |
392 | #ifdef CONFIG_NETFILTER_DEBUG | |
393 | ((struct ip6t_entry *)table_base)->comefrom | |
394 | = 0xeeeeeeec; | |
395 | #endif | |
396 | verdict = t->u.kernel.target->target(pskb, | |
397 | in, out, | |
398 | hook, | |
399 | t->data, | |
400 | userdata); | |
401 | ||
402 | #ifdef CONFIG_NETFILTER_DEBUG | |
403 | if (((struct ip6t_entry *)table_base)->comefrom | |
404 | != 0xeeeeeeec | |
405 | && verdict == IP6T_CONTINUE) { | |
406 | printk("Target %s reentered!\n", | |
407 | t->u.kernel.target->name); | |
408 | verdict = NF_DROP; | |
409 | } | |
410 | ((struct ip6t_entry *)table_base)->comefrom | |
411 | = 0x57acc001; | |
412 | #endif | |
413 | if (verdict == IP6T_CONTINUE) | |
414 | e = (void *)e + e->next_offset; | |
415 | else | |
416 | /* Verdict */ | |
417 | break; | |
418 | } | |
419 | } else { | |
420 | ||
421 | no_match: | |
422 | e = (void *)e + e->next_offset; | |
423 | } | |
424 | } while (!hotdrop); | |
425 | ||
426 | #ifdef CONFIG_NETFILTER_DEBUG | |
427 | ((struct ip6t_entry *)table_base)->comefrom = 0xdead57ac; | |
428 | #endif | |
429 | read_unlock_bh(&table->lock); | |
430 | ||
431 | #ifdef DEBUG_ALLOW_ALL | |
432 | return NF_ACCEPT; | |
433 | #else | |
434 | if (hotdrop) | |
435 | return NF_DROP; | |
436 | else return verdict; | |
437 | #endif | |
438 | } | |
439 | ||
6b7d31fc HW |
440 | /* |
441 | * These are weird, but module loading must not be done with mutex | |
442 | * held (since they will register), and we have to have a single | |
443 | * function to use try_then_request_module(). | |
444 | */ | |
445 | ||
446 | /* Find table by name, grabs mutex & ref. Returns ERR_PTR() on error. */ | |
447 | static inline struct ip6t_table *find_table_lock(const char *name) | |
1da177e4 | 448 | { |
6b7d31fc | 449 | struct ip6t_table *t; |
1da177e4 | 450 | |
6b7d31fc HW |
451 | if (down_interruptible(&ip6t_mutex) != 0) |
452 | return ERR_PTR(-EINTR); | |
1da177e4 | 453 | |
6b7d31fc HW |
454 | list_for_each_entry(t, &ip6t_tables, list) |
455 | if (strcmp(t->name, name) == 0 && try_module_get(t->me)) | |
456 | return t; | |
457 | up(&ip6t_mutex); | |
458 | return NULL; | |
459 | } | |
1da177e4 | 460 | |
6b7d31fc HW |
461 | /* Find match, grabs ref. Returns ERR_PTR() on error. */ |
462 | static inline struct ip6t_match *find_match(const char *name, u8 revision) | |
463 | { | |
464 | struct ip6t_match *m; | |
465 | int err = 0; | |
466 | ||
467 | if (down_interruptible(&ip6t_mutex) != 0) | |
468 | return ERR_PTR(-EINTR); | |
469 | ||
470 | list_for_each_entry(m, &ip6t_match, list) { | |
471 | if (strcmp(m->name, name) == 0) { | |
472 | if (m->revision == revision) { | |
473 | if (try_module_get(m->me)) { | |
474 | up(&ip6t_mutex); | |
475 | return m; | |
476 | } | |
477 | } else | |
478 | err = -EPROTOTYPE; /* Found something. */ | |
479 | } | |
1da177e4 | 480 | } |
6b7d31fc HW |
481 | up(&ip6t_mutex); |
482 | return ERR_PTR(err); | |
1da177e4 LT |
483 | } |
484 | ||
6b7d31fc HW |
485 | /* Find target, grabs ref. Returns ERR_PTR() on error. */ |
486 | static inline struct ip6t_target *find_target(const char *name, u8 revision) | |
1da177e4 | 487 | { |
6b7d31fc HW |
488 | struct ip6t_target *t; |
489 | int err = 0; | |
490 | ||
491 | if (down_interruptible(&ip6t_mutex) != 0) | |
492 | return ERR_PTR(-EINTR); | |
493 | ||
494 | list_for_each_entry(t, &ip6t_target, list) { | |
495 | if (strcmp(t->name, name) == 0) { | |
496 | if (t->revision == revision) { | |
497 | if (try_module_get(t->me)) { | |
498 | up(&ip6t_mutex); | |
499 | return t; | |
500 | } | |
501 | } else | |
502 | err = -EPROTOTYPE; /* Found something. */ | |
503 | } | |
1da177e4 | 504 | } |
6b7d31fc HW |
505 | up(&ip6t_mutex); |
506 | return ERR_PTR(err); | |
507 | } | |
1da177e4 | 508 | |
6b7d31fc HW |
509 | struct ip6t_target *ip6t_find_target(const char *name, u8 revision) |
510 | { | |
511 | struct ip6t_target *target; | |
512 | ||
513 | target = try_then_request_module(find_target(name, revision), | |
514 | "ip6t_%s", name); | |
515 | if (IS_ERR(target) || !target) | |
516 | return NULL; | |
517 | return target; | |
1da177e4 | 518 | } |
1da177e4 | 519 | |
6b7d31fc | 520 | static int match_revfn(const char *name, u8 revision, int *bestp) |
1da177e4 | 521 | { |
6b7d31fc HW |
522 | struct ip6t_match *m; |
523 | int have_rev = 0; | |
524 | ||
525 | list_for_each_entry(m, &ip6t_match, list) { | |
526 | if (strcmp(m->name, name) == 0) { | |
527 | if (m->revision > *bestp) | |
528 | *bestp = m->revision; | |
529 | if (m->revision == revision) | |
530 | have_rev = 1; | |
531 | } | |
532 | } | |
533 | return have_rev; | |
1da177e4 LT |
534 | } |
535 | ||
6b7d31fc | 536 | static int target_revfn(const char *name, u8 revision, int *bestp) |
1da177e4 | 537 | { |
6b7d31fc HW |
538 | struct ip6t_target *t; |
539 | int have_rev = 0; | |
540 | ||
541 | list_for_each_entry(t, &ip6t_target, list) { | |
542 | if (strcmp(t->name, name) == 0) { | |
543 | if (t->revision > *bestp) | |
544 | *bestp = t->revision; | |
545 | if (t->revision == revision) | |
546 | have_rev = 1; | |
547 | } | |
548 | } | |
549 | return have_rev; | |
1da177e4 LT |
550 | } |
551 | ||
6b7d31fc HW |
552 | /* Returns true or fals (if no such extension at all) */ |
553 | static inline int find_revision(const char *name, u8 revision, | |
554 | int (*revfn)(const char *, u8, int *), | |
555 | int *err) | |
1da177e4 | 556 | { |
6b7d31fc HW |
557 | int have_rev, best = -1; |
558 | ||
559 | if (down_interruptible(&ip6t_mutex) != 0) { | |
560 | *err = -EINTR; | |
561 | return 1; | |
562 | } | |
563 | have_rev = revfn(name, revision, &best); | |
564 | up(&ip6t_mutex); | |
565 | ||
566 | /* Nothing at all? Return 0 to try loading module. */ | |
567 | if (best == -1) { | |
568 | *err = -ENOENT; | |
569 | return 0; | |
570 | } | |
571 | ||
572 | *err = best; | |
573 | if (!have_rev) | |
574 | *err = -EPROTONOSUPPORT; | |
575 | return 1; | |
1da177e4 LT |
576 | } |
577 | ||
6b7d31fc | 578 | |
1da177e4 LT |
579 | /* All zeroes == unconditional rule. */ |
580 | static inline int | |
581 | unconditional(const struct ip6t_ip6 *ipv6) | |
582 | { | |
583 | unsigned int i; | |
584 | ||
585 | for (i = 0; i < sizeof(*ipv6); i++) | |
586 | if (((char *)ipv6)[i]) | |
587 | break; | |
588 | ||
589 | return (i == sizeof(*ipv6)); | |
590 | } | |
591 | ||
592 | /* Figures out from what hook each rule can be called: returns 0 if | |
593 | there are loops. Puts hook bitmask in comefrom. */ | |
594 | static int | |
31836064 ED |
595 | mark_source_chains(struct ip6t_table_info *newinfo, |
596 | unsigned int valid_hooks, void *entry0) | |
1da177e4 LT |
597 | { |
598 | unsigned int hook; | |
599 | ||
600 | /* No recursion; use packet counter to save back ptrs (reset | |
601 | to 0 as we leave), and comefrom to save source hook bitmask */ | |
602 | for (hook = 0; hook < NF_IP6_NUMHOOKS; hook++) { | |
603 | unsigned int pos = newinfo->hook_entry[hook]; | |
604 | struct ip6t_entry *e | |
31836064 | 605 | = (struct ip6t_entry *)(entry0 + pos); |
1da177e4 LT |
606 | |
607 | if (!(valid_hooks & (1 << hook))) | |
608 | continue; | |
609 | ||
610 | /* Set initial back pointer. */ | |
611 | e->counters.pcnt = pos; | |
612 | ||
613 | for (;;) { | |
614 | struct ip6t_standard_target *t | |
615 | = (void *)ip6t_get_target(e); | |
616 | ||
617 | if (e->comefrom & (1 << NF_IP6_NUMHOOKS)) { | |
618 | printk("iptables: loop hook %u pos %u %08X.\n", | |
619 | hook, pos, e->comefrom); | |
620 | return 0; | |
621 | } | |
622 | e->comefrom | |
623 | |= ((1 << hook) | (1 << NF_IP6_NUMHOOKS)); | |
624 | ||
625 | /* Unconditional return/END. */ | |
626 | if (e->target_offset == sizeof(struct ip6t_entry) | |
627 | && (strcmp(t->target.u.user.name, | |
628 | IP6T_STANDARD_TARGET) == 0) | |
629 | && t->verdict < 0 | |
630 | && unconditional(&e->ipv6)) { | |
631 | unsigned int oldpos, size; | |
632 | ||
633 | /* Return: backtrack through the last | |
634 | big jump. */ | |
635 | do { | |
636 | e->comefrom ^= (1<<NF_IP6_NUMHOOKS); | |
637 | #ifdef DEBUG_IP_FIREWALL_USER | |
638 | if (e->comefrom | |
639 | & (1 << NF_IP6_NUMHOOKS)) { | |
640 | duprintf("Back unset " | |
641 | "on hook %u " | |
642 | "rule %u\n", | |
643 | hook, pos); | |
644 | } | |
645 | #endif | |
646 | oldpos = pos; | |
647 | pos = e->counters.pcnt; | |
648 | e->counters.pcnt = 0; | |
649 | ||
650 | /* We're at the start. */ | |
651 | if (pos == oldpos) | |
652 | goto next; | |
653 | ||
654 | e = (struct ip6t_entry *) | |
31836064 | 655 | (entry0 + pos); |
1da177e4 LT |
656 | } while (oldpos == pos + e->next_offset); |
657 | ||
658 | /* Move along one */ | |
659 | size = e->next_offset; | |
660 | e = (struct ip6t_entry *) | |
31836064 | 661 | (entry0 + pos + size); |
1da177e4 LT |
662 | e->counters.pcnt = pos; |
663 | pos += size; | |
664 | } else { | |
665 | int newpos = t->verdict; | |
666 | ||
667 | if (strcmp(t->target.u.user.name, | |
668 | IP6T_STANDARD_TARGET) == 0 | |
669 | && newpos >= 0) { | |
670 | /* This a jump; chase it. */ | |
671 | duprintf("Jump rule %u -> %u\n", | |
672 | pos, newpos); | |
673 | } else { | |
674 | /* ... this is a fallthru */ | |
675 | newpos = pos + e->next_offset; | |
676 | } | |
677 | e = (struct ip6t_entry *) | |
31836064 | 678 | (entry0 + newpos); |
1da177e4 LT |
679 | e->counters.pcnt = pos; |
680 | pos = newpos; | |
681 | } | |
682 | } | |
683 | next: | |
684 | duprintf("Finished chain %u\n", hook); | |
685 | } | |
686 | return 1; | |
687 | } | |
688 | ||
689 | static inline int | |
690 | cleanup_match(struct ip6t_entry_match *m, unsigned int *i) | |
691 | { | |
692 | if (i && (*i)-- == 0) | |
693 | return 1; | |
694 | ||
695 | if (m->u.kernel.match->destroy) | |
696 | m->u.kernel.match->destroy(m->data, | |
697 | m->u.match_size - sizeof(*m)); | |
698 | module_put(m->u.kernel.match->me); | |
699 | return 0; | |
700 | } | |
701 | ||
702 | static inline int | |
703 | standard_check(const struct ip6t_entry_target *t, | |
704 | unsigned int max_offset) | |
705 | { | |
706 | struct ip6t_standard_target *targ = (void *)t; | |
707 | ||
708 | /* Check standard info. */ | |
709 | if (t->u.target_size | |
710 | != IP6T_ALIGN(sizeof(struct ip6t_standard_target))) { | |
711 | duprintf("standard_check: target size %u != %u\n", | |
712 | t->u.target_size, | |
713 | IP6T_ALIGN(sizeof(struct ip6t_standard_target))); | |
714 | return 0; | |
715 | } | |
716 | ||
717 | if (targ->verdict >= 0 | |
718 | && targ->verdict > max_offset - sizeof(struct ip6t_entry)) { | |
719 | duprintf("ip6t_standard_check: bad verdict (%i)\n", | |
720 | targ->verdict); | |
721 | return 0; | |
722 | } | |
723 | ||
724 | if (targ->verdict < -NF_MAX_VERDICT - 1) { | |
725 | duprintf("ip6t_standard_check: bad negative verdict (%i)\n", | |
726 | targ->verdict); | |
727 | return 0; | |
728 | } | |
729 | return 1; | |
730 | } | |
731 | ||
732 | static inline int | |
733 | check_match(struct ip6t_entry_match *m, | |
734 | const char *name, | |
735 | const struct ip6t_ip6 *ipv6, | |
736 | unsigned int hookmask, | |
737 | unsigned int *i) | |
738 | { | |
1da177e4 LT |
739 | struct ip6t_match *match; |
740 | ||
6b7d31fc HW |
741 | match = try_then_request_module(find_match(m->u.user.name, |
742 | m->u.user.revision), | |
743 | "ip6t_%s", m->u.user.name); | |
744 | if (IS_ERR(match) || !match) { | |
745 | duprintf("check_match: `%s' not found\n", m->u.user.name); | |
746 | return match ? PTR_ERR(match) : -ENOENT; | |
1da177e4 LT |
747 | } |
748 | m->u.kernel.match = match; | |
1da177e4 LT |
749 | |
750 | if (m->u.kernel.match->checkentry | |
751 | && !m->u.kernel.match->checkentry(name, ipv6, m->data, | |
752 | m->u.match_size - sizeof(*m), | |
753 | hookmask)) { | |
754 | module_put(m->u.kernel.match->me); | |
755 | duprintf("ip_tables: check failed for `%s'.\n", | |
756 | m->u.kernel.match->name); | |
757 | return -EINVAL; | |
758 | } | |
759 | ||
760 | (*i)++; | |
761 | return 0; | |
762 | } | |
763 | ||
764 | static struct ip6t_target ip6t_standard_target; | |
765 | ||
766 | static inline int | |
767 | check_entry(struct ip6t_entry *e, const char *name, unsigned int size, | |
768 | unsigned int *i) | |
769 | { | |
770 | struct ip6t_entry_target *t; | |
771 | struct ip6t_target *target; | |
772 | int ret; | |
773 | unsigned int j; | |
774 | ||
775 | if (!ip6_checkentry(&e->ipv6)) { | |
776 | duprintf("ip_tables: ip check failed %p %s.\n", e, name); | |
777 | return -EINVAL; | |
778 | } | |
779 | ||
780 | j = 0; | |
781 | ret = IP6T_MATCH_ITERATE(e, check_match, name, &e->ipv6, e->comefrom, &j); | |
782 | if (ret != 0) | |
783 | goto cleanup_matches; | |
784 | ||
785 | t = ip6t_get_target(e); | |
6b7d31fc HW |
786 | target = try_then_request_module(find_target(t->u.user.name, |
787 | t->u.user.revision), | |
788 | "ip6t_%s", t->u.user.name); | |
789 | if (IS_ERR(target) || !target) { | |
1da177e4 | 790 | duprintf("check_entry: `%s' not found\n", t->u.user.name); |
6b7d31fc | 791 | ret = target ? PTR_ERR(target) : -ENOENT; |
1da177e4 LT |
792 | goto cleanup_matches; |
793 | } | |
794 | t->u.kernel.target = target; | |
6b7d31fc | 795 | |
1da177e4 LT |
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, | |
31836064 | 888 | void *entry0, |
1da177e4 LT |
889 | unsigned int size, |
890 | unsigned int number, | |
891 | const unsigned int *hook_entries, | |
892 | const unsigned int *underflows) | |
893 | { | |
894 | unsigned int i; | |
895 | int ret; | |
896 | ||
897 | newinfo->size = size; | |
898 | newinfo->number = number; | |
899 | ||
900 | /* Init all hooks to impossible value. */ | |
901 | for (i = 0; i < NF_IP6_NUMHOOKS; i++) { | |
902 | newinfo->hook_entry[i] = 0xFFFFFFFF; | |
903 | newinfo->underflow[i] = 0xFFFFFFFF; | |
904 | } | |
905 | ||
906 | duprintf("translate_table: size %u\n", newinfo->size); | |
907 | i = 0; | |
908 | /* Walk through entries, checking offsets. */ | |
31836064 | 909 | ret = IP6T_ENTRY_ITERATE(entry0, newinfo->size, |
1da177e4 LT |
910 | check_entry_size_and_hooks, |
911 | newinfo, | |
31836064 ED |
912 | entry0, |
913 | entry0 + size, | |
1da177e4 LT |
914 | hook_entries, underflows, &i); |
915 | if (ret != 0) | |
916 | return ret; | |
917 | ||
918 | if (i != number) { | |
919 | duprintf("translate_table: %u not %u entries\n", | |
920 | i, number); | |
921 | return -EINVAL; | |
922 | } | |
923 | ||
924 | /* Check hooks all assigned */ | |
925 | for (i = 0; i < NF_IP6_NUMHOOKS; i++) { | |
926 | /* Only hooks which are valid */ | |
927 | if (!(valid_hooks & (1 << i))) | |
928 | continue; | |
929 | if (newinfo->hook_entry[i] == 0xFFFFFFFF) { | |
930 | duprintf("Invalid hook entry %u %u\n", | |
931 | i, hook_entries[i]); | |
932 | return -EINVAL; | |
933 | } | |
934 | if (newinfo->underflow[i] == 0xFFFFFFFF) { | |
935 | duprintf("Invalid underflow %u %u\n", | |
936 | i, underflows[i]); | |
937 | return -EINVAL; | |
938 | } | |
939 | } | |
940 | ||
31836064 | 941 | if (!mark_source_chains(newinfo, valid_hooks, entry0)) |
1da177e4 LT |
942 | return -ELOOP; |
943 | ||
944 | /* Finally, each sanity check must pass */ | |
945 | i = 0; | |
31836064 | 946 | ret = IP6T_ENTRY_ITERATE(entry0, newinfo->size, |
1da177e4 LT |
947 | check_entry, name, size, &i); |
948 | ||
949 | if (ret != 0) { | |
31836064 | 950 | IP6T_ENTRY_ITERATE(entry0, newinfo->size, |
1da177e4 LT |
951 | cleanup_entry, &i); |
952 | return ret; | |
953 | } | |
954 | ||
955 | /* And one copy for every other CPU */ | |
c8923c6b | 956 | for_each_cpu(i) { |
31836064 ED |
957 | if (newinfo->entries[i] && newinfo->entries[i] != entry0) |
958 | memcpy(newinfo->entries[i], entry0, newinfo->size); | |
1da177e4 LT |
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 | { | |
31836064 | 974 | int cpu; |
1da177e4 | 975 | |
31836064 ED |
976 | for_each_cpu(cpu) { |
977 | struct ip6t_entry *table_base = newinfo->entries[cpu]; | |
978 | if (table_base) | |
979 | table_base->comefrom = 0xdead57ac; | |
1da177e4 LT |
980 | } |
981 | } | |
982 | #endif | |
983 | ||
984 | /* Do the substitution. */ | |
985 | write_lock_bh(&table->lock); | |
986 | /* Check inside lock: is the old number correct? */ | |
987 | if (num_counters != table->private->number) { | |
988 | duprintf("num_counters != table->private->number (%u/%u)\n", | |
989 | num_counters, table->private->number); | |
990 | write_unlock_bh(&table->lock); | |
991 | *error = -EAGAIN; | |
992 | return NULL; | |
993 | } | |
994 | oldinfo = table->private; | |
995 | table->private = newinfo; | |
996 | newinfo->initial_entries = oldinfo->initial_entries; | |
997 | write_unlock_bh(&table->lock); | |
998 | ||
999 | return oldinfo; | |
1000 | } | |
1001 | ||
1002 | /* Gets counters. */ | |
1003 | static inline int | |
1004 | add_entry_to_counter(const struct ip6t_entry *e, | |
1005 | struct ip6t_counters total[], | |
1006 | unsigned int *i) | |
1007 | { | |
1008 | ADD_COUNTER(total[*i], e->counters.bcnt, e->counters.pcnt); | |
1009 | ||
1010 | (*i)++; | |
1011 | return 0; | |
1012 | } | |
1013 | ||
31836064 ED |
1014 | static inline int |
1015 | set_entry_to_counter(const struct ip6t_entry *e, | |
1016 | struct ip6t_counters total[], | |
1017 | unsigned int *i) | |
1018 | { | |
1019 | SET_COUNTER(total[*i], e->counters.bcnt, e->counters.pcnt); | |
1020 | ||
1021 | (*i)++; | |
1022 | return 0; | |
1023 | } | |
1024 | ||
1da177e4 LT |
1025 | static void |
1026 | get_counters(const struct ip6t_table_info *t, | |
1027 | struct ip6t_counters counters[]) | |
1028 | { | |
1029 | unsigned int cpu; | |
1030 | unsigned int i; | |
31836064 ED |
1031 | unsigned int curcpu; |
1032 | ||
1033 | /* Instead of clearing (by a previous call to memset()) | |
1034 | * the counters and using adds, we set the counters | |
1035 | * with data used by 'current' CPU | |
1036 | * We dont care about preemption here. | |
1037 | */ | |
1038 | curcpu = raw_smp_processor_id(); | |
1039 | ||
1040 | i = 0; | |
1041 | IP6T_ENTRY_ITERATE(t->entries[curcpu], | |
1042 | t->size, | |
1043 | set_entry_to_counter, | |
1044 | counters, | |
1045 | &i); | |
1da177e4 | 1046 | |
c8923c6b | 1047 | for_each_cpu(cpu) { |
31836064 ED |
1048 | if (cpu == curcpu) |
1049 | continue; | |
1da177e4 | 1050 | i = 0; |
31836064 | 1051 | IP6T_ENTRY_ITERATE(t->entries[cpu], |
1da177e4 LT |
1052 | t->size, |
1053 | add_entry_to_counter, | |
1054 | counters, | |
1055 | &i); | |
1056 | } | |
1057 | } | |
1058 | ||
1059 | static int | |
1060 | copy_entries_to_user(unsigned int total_size, | |
1061 | struct ip6t_table *table, | |
1062 | void __user *userptr) | |
1063 | { | |
1064 | unsigned int off, num, countersize; | |
1065 | struct ip6t_entry *e; | |
1066 | struct ip6t_counters *counters; | |
1067 | int ret = 0; | |
31836064 | 1068 | void *loc_cpu_entry; |
1da177e4 LT |
1069 | |
1070 | /* We need atomic snapshot of counters: rest doesn't change | |
1071 | (other than comefrom, which userspace doesn't care | |
1072 | about). */ | |
1073 | countersize = sizeof(struct ip6t_counters) * table->private->number; | |
1074 | counters = vmalloc(countersize); | |
1075 | ||
1076 | if (counters == NULL) | |
1077 | return -ENOMEM; | |
1078 | ||
1079 | /* First, sum counters... */ | |
1da177e4 LT |
1080 | write_lock_bh(&table->lock); |
1081 | get_counters(table->private, counters); | |
1082 | write_unlock_bh(&table->lock); | |
1083 | ||
31836064 ED |
1084 | /* choose the copy that is on ourc node/cpu */ |
1085 | loc_cpu_entry = table->private->entries[raw_smp_processor_id()]; | |
1086 | if (copy_to_user(userptr, loc_cpu_entry, total_size) != 0) { | |
1da177e4 LT |
1087 | ret = -EFAULT; |
1088 | goto free_counters; | |
1089 | } | |
1090 | ||
1091 | /* FIXME: use iterator macros --RR */ | |
1092 | /* ... then go back and fix counters and names */ | |
1093 | for (off = 0, num = 0; off < total_size; off += e->next_offset, num++){ | |
1094 | unsigned int i; | |
1095 | struct ip6t_entry_match *m; | |
1096 | struct ip6t_entry_target *t; | |
1097 | ||
31836064 | 1098 | e = (struct ip6t_entry *)(loc_cpu_entry + off); |
1da177e4 LT |
1099 | if (copy_to_user(userptr + off |
1100 | + offsetof(struct ip6t_entry, counters), | |
1101 | &counters[num], | |
1102 | sizeof(counters[num])) != 0) { | |
1103 | ret = -EFAULT; | |
1104 | goto free_counters; | |
1105 | } | |
1106 | ||
1107 | for (i = sizeof(struct ip6t_entry); | |
1108 | i < e->target_offset; | |
1109 | i += m->u.match_size) { | |
1110 | m = (void *)e + i; | |
1111 | ||
1112 | if (copy_to_user(userptr + off + i | |
1113 | + offsetof(struct ip6t_entry_match, | |
1114 | u.user.name), | |
1115 | m->u.kernel.match->name, | |
1116 | strlen(m->u.kernel.match->name)+1) | |
1117 | != 0) { | |
1118 | ret = -EFAULT; | |
1119 | goto free_counters; | |
1120 | } | |
1121 | } | |
1122 | ||
1123 | t = ip6t_get_target(e); | |
1124 | if (copy_to_user(userptr + off + e->target_offset | |
1125 | + offsetof(struct ip6t_entry_target, | |
1126 | u.user.name), | |
1127 | t->u.kernel.target->name, | |
1128 | strlen(t->u.kernel.target->name)+1) != 0) { | |
1129 | ret = -EFAULT; | |
1130 | goto free_counters; | |
1131 | } | |
1132 | } | |
1133 | ||
1134 | free_counters: | |
1135 | vfree(counters); | |
1136 | return ret; | |
1137 | } | |
1138 | ||
1139 | static int | |
1140 | get_entries(const struct ip6t_get_entries *entries, | |
1141 | struct ip6t_get_entries __user *uptr) | |
1142 | { | |
1143 | int ret; | |
1144 | struct ip6t_table *t; | |
1145 | ||
6b7d31fc HW |
1146 | t = find_table_lock(entries->name); |
1147 | if (t && !IS_ERR(t)) { | |
1da177e4 LT |
1148 | duprintf("t->private->number = %u\n", |
1149 | t->private->number); | |
1150 | if (entries->size == t->private->size) | |
1151 | ret = copy_entries_to_user(t->private->size, | |
1152 | t, uptr->entrytable); | |
1153 | else { | |
1154 | duprintf("get_entries: I've got %u not %u!\n", | |
1155 | t->private->size, | |
1156 | entries->size); | |
1157 | ret = -EINVAL; | |
1158 | } | |
6b7d31fc | 1159 | module_put(t->me); |
1da177e4 LT |
1160 | up(&ip6t_mutex); |
1161 | } else | |
6b7d31fc | 1162 | ret = t ? PTR_ERR(t) : -ENOENT; |
1da177e4 LT |
1163 | |
1164 | return ret; | |
1165 | } | |
1166 | ||
31836064 ED |
1167 | static void free_table_info(struct ip6t_table_info *info) |
1168 | { | |
1169 | int cpu; | |
1170 | for_each_cpu(cpu) { | |
1171 | if (info->size <= PAGE_SIZE) | |
1172 | kfree(info->entries[cpu]); | |
1173 | else | |
1174 | vfree(info->entries[cpu]); | |
1175 | } | |
1176 | kfree(info); | |
1177 | } | |
1178 | ||
1179 | static struct ip6t_table_info *alloc_table_info(unsigned int size) | |
1180 | { | |
1181 | struct ip6t_table_info *newinfo; | |
1182 | int cpu; | |
1183 | ||
1184 | newinfo = kzalloc(sizeof(struct ip6t_table_info), GFP_KERNEL); | |
1185 | if (!newinfo) | |
1186 | return NULL; | |
1187 | ||
1188 | newinfo->size = size; | |
1189 | ||
1190 | for_each_cpu(cpu) { | |
1191 | if (size <= PAGE_SIZE) | |
1192 | newinfo->entries[cpu] = kmalloc_node(size, | |
1193 | GFP_KERNEL, | |
1194 | cpu_to_node(cpu)); | |
1195 | else | |
1196 | newinfo->entries[cpu] = vmalloc_node(size, | |
1197 | cpu_to_node(cpu)); | |
1198 | if (newinfo->entries[cpu] == NULL) { | |
1199 | free_table_info(newinfo); | |
1200 | return NULL; | |
1201 | } | |
1202 | } | |
1203 | ||
1204 | return newinfo; | |
1205 | } | |
1206 | ||
1da177e4 LT |
1207 | static int |
1208 | do_replace(void __user *user, unsigned int len) | |
1209 | { | |
1210 | int ret; | |
1211 | struct ip6t_replace tmp; | |
1212 | struct ip6t_table *t; | |
1213 | struct ip6t_table_info *newinfo, *oldinfo; | |
1214 | struct ip6t_counters *counters; | |
31836064 | 1215 | void *loc_cpu_entry, *loc_cpu_old_entry; |
1da177e4 LT |
1216 | |
1217 | if (copy_from_user(&tmp, user, sizeof(tmp)) != 0) | |
1218 | return -EFAULT; | |
1219 | ||
1220 | /* Pedantry: prevent them from hitting BUG() in vmalloc.c --RR */ | |
1221 | if ((SMP_ALIGN(tmp.size) >> PAGE_SHIFT) + 2 > num_physpages) | |
1222 | return -ENOMEM; | |
1223 | ||
31836064 | 1224 | newinfo = alloc_table_info(tmp.size); |
1da177e4 LT |
1225 | if (!newinfo) |
1226 | return -ENOMEM; | |
1227 | ||
31836064 ED |
1228 | /* choose the copy that is on our node/cpu */ |
1229 | loc_cpu_entry = newinfo->entries[raw_smp_processor_id()]; | |
1230 | if (copy_from_user(loc_cpu_entry, user + sizeof(tmp), | |
1da177e4 LT |
1231 | tmp.size) != 0) { |
1232 | ret = -EFAULT; | |
1233 | goto free_newinfo; | |
1234 | } | |
1235 | ||
1236 | counters = vmalloc(tmp.num_counters * sizeof(struct ip6t_counters)); | |
1237 | if (!counters) { | |
1238 | ret = -ENOMEM; | |
1239 | goto free_newinfo; | |
1240 | } | |
1da177e4 LT |
1241 | |
1242 | ret = translate_table(tmp.name, tmp.valid_hooks, | |
31836064 | 1243 | newinfo, loc_cpu_entry, tmp.size, tmp.num_entries, |
1da177e4 LT |
1244 | tmp.hook_entry, tmp.underflow); |
1245 | if (ret != 0) | |
1246 | goto free_newinfo_counters; | |
1247 | ||
1248 | duprintf("ip_tables: Translated table\n"); | |
1249 | ||
6b7d31fc HW |
1250 | t = try_then_request_module(find_table_lock(tmp.name), |
1251 | "ip6table_%s", tmp.name); | |
1252 | if (!t || IS_ERR(t)) { | |
1253 | ret = t ? PTR_ERR(t) : -ENOENT; | |
1da177e4 | 1254 | goto free_newinfo_counters_untrans; |
6b7d31fc | 1255 | } |
1da177e4 LT |
1256 | |
1257 | /* You lied! */ | |
1258 | if (tmp.valid_hooks != t->valid_hooks) { | |
1259 | duprintf("Valid hook crap: %08X vs %08X\n", | |
1260 | tmp.valid_hooks, t->valid_hooks); | |
1261 | ret = -EINVAL; | |
6b7d31fc | 1262 | goto put_module; |
1da177e4 LT |
1263 | } |
1264 | ||
1265 | oldinfo = replace_table(t, tmp.num_counters, newinfo, &ret); | |
1266 | if (!oldinfo) | |
1267 | goto put_module; | |
1268 | ||
1269 | /* Update module usage count based on number of rules */ | |
1270 | duprintf("do_replace: oldnum=%u, initnum=%u, newnum=%u\n", | |
1271 | oldinfo->number, oldinfo->initial_entries, newinfo->number); | |
1272 | if ((oldinfo->number > oldinfo->initial_entries) || | |
1273 | (newinfo->number <= oldinfo->initial_entries)) | |
1274 | module_put(t->me); | |
1275 | if ((oldinfo->number > oldinfo->initial_entries) && | |
1276 | (newinfo->number <= oldinfo->initial_entries)) | |
1277 | module_put(t->me); | |
1278 | ||
1279 | /* Get the old counters. */ | |
1280 | get_counters(oldinfo, counters); | |
1281 | /* Decrease module usage counts and free resource */ | |
31836064 ED |
1282 | loc_cpu_old_entry = oldinfo->entries[raw_smp_processor_id()]; |
1283 | IP6T_ENTRY_ITERATE(loc_cpu_old_entry, oldinfo->size, cleanup_entry,NULL); | |
1284 | free_table_info(oldinfo); | |
1da177e4 LT |
1285 | if (copy_to_user(tmp.counters, counters, |
1286 | sizeof(struct ip6t_counters) * tmp.num_counters) != 0) | |
1287 | ret = -EFAULT; | |
1288 | vfree(counters); | |
1289 | up(&ip6t_mutex); | |
1290 | return ret; | |
1291 | ||
1292 | put_module: | |
1293 | module_put(t->me); | |
1da177e4 LT |
1294 | up(&ip6t_mutex); |
1295 | free_newinfo_counters_untrans: | |
31836064 | 1296 | IP6T_ENTRY_ITERATE(loc_cpu_entry, newinfo->size, cleanup_entry,NULL); |
1da177e4 LT |
1297 | free_newinfo_counters: |
1298 | vfree(counters); | |
1299 | free_newinfo: | |
31836064 | 1300 | free_table_info(newinfo); |
1da177e4 LT |
1301 | return ret; |
1302 | } | |
1303 | ||
1304 | /* We're lazy, and add to the first CPU; overflow works its fey magic | |
1305 | * and everything is OK. */ | |
1306 | static inline int | |
1307 | add_counter_to_entry(struct ip6t_entry *e, | |
1308 | const struct ip6t_counters addme[], | |
1309 | unsigned int *i) | |
1310 | { | |
1311 | #if 0 | |
1312 | duprintf("add_counter: Entry %u %lu/%lu + %lu/%lu\n", | |
1313 | *i, | |
1314 | (long unsigned int)e->counters.pcnt, | |
1315 | (long unsigned int)e->counters.bcnt, | |
1316 | (long unsigned int)addme[*i].pcnt, | |
1317 | (long unsigned int)addme[*i].bcnt); | |
1318 | #endif | |
1319 | ||
1320 | ADD_COUNTER(e->counters, addme[*i].bcnt, addme[*i].pcnt); | |
1321 | ||
1322 | (*i)++; | |
1323 | return 0; | |
1324 | } | |
1325 | ||
1326 | static int | |
1327 | do_add_counters(void __user *user, unsigned int len) | |
1328 | { | |
1329 | unsigned int i; | |
1330 | struct ip6t_counters_info tmp, *paddc; | |
1331 | struct ip6t_table *t; | |
6b7d31fc | 1332 | int ret = 0; |
31836064 | 1333 | void *loc_cpu_entry; |
1da177e4 LT |
1334 | |
1335 | if (copy_from_user(&tmp, user, sizeof(tmp)) != 0) | |
1336 | return -EFAULT; | |
1337 | ||
1338 | if (len != sizeof(tmp) + tmp.num_counters*sizeof(struct ip6t_counters)) | |
1339 | return -EINVAL; | |
1340 | ||
1341 | paddc = vmalloc(len); | |
1342 | if (!paddc) | |
1343 | return -ENOMEM; | |
1344 | ||
1345 | if (copy_from_user(paddc, user, len) != 0) { | |
1346 | ret = -EFAULT; | |
1347 | goto free; | |
1348 | } | |
1349 | ||
6b7d31fc HW |
1350 | t = find_table_lock(tmp.name); |
1351 | if (!t || IS_ERR(t)) { | |
1352 | ret = t ? PTR_ERR(t) : -ENOENT; | |
1da177e4 | 1353 | goto free; |
6b7d31fc | 1354 | } |
1da177e4 LT |
1355 | |
1356 | write_lock_bh(&t->lock); | |
1357 | if (t->private->number != paddc->num_counters) { | |
1358 | ret = -EINVAL; | |
1359 | goto unlock_up_free; | |
1360 | } | |
1361 | ||
1362 | i = 0; | |
31836064 ED |
1363 | /* Choose the copy that is on our node */ |
1364 | loc_cpu_entry = t->private->entries[smp_processor_id()]; | |
1365 | IP6T_ENTRY_ITERATE(loc_cpu_entry, | |
1da177e4 LT |
1366 | t->private->size, |
1367 | add_counter_to_entry, | |
1368 | paddc->counters, | |
1369 | &i); | |
1370 | unlock_up_free: | |
1371 | write_unlock_bh(&t->lock); | |
1372 | up(&ip6t_mutex); | |
6b7d31fc | 1373 | module_put(t->me); |
1da177e4 LT |
1374 | free: |
1375 | vfree(paddc); | |
1376 | ||
1377 | return ret; | |
1378 | } | |
1379 | ||
1380 | static int | |
1381 | do_ip6t_set_ctl(struct sock *sk, int cmd, void __user *user, unsigned int len) | |
1382 | { | |
1383 | int ret; | |
1384 | ||
1385 | if (!capable(CAP_NET_ADMIN)) | |
1386 | return -EPERM; | |
1387 | ||
1388 | switch (cmd) { | |
1389 | case IP6T_SO_SET_REPLACE: | |
1390 | ret = do_replace(user, len); | |
1391 | break; | |
1392 | ||
1393 | case IP6T_SO_SET_ADD_COUNTERS: | |
1394 | ret = do_add_counters(user, len); | |
1395 | break; | |
1396 | ||
1397 | default: | |
1398 | duprintf("do_ip6t_set_ctl: unknown request %i\n", cmd); | |
1399 | ret = -EINVAL; | |
1400 | } | |
1401 | ||
1402 | return ret; | |
1403 | } | |
1404 | ||
1405 | static int | |
1406 | do_ip6t_get_ctl(struct sock *sk, int cmd, void __user *user, int *len) | |
1407 | { | |
1408 | int ret; | |
1409 | ||
1410 | if (!capable(CAP_NET_ADMIN)) | |
1411 | return -EPERM; | |
1412 | ||
1413 | switch (cmd) { | |
1414 | case IP6T_SO_GET_INFO: { | |
1415 | char name[IP6T_TABLE_MAXNAMELEN]; | |
1416 | struct ip6t_table *t; | |
1417 | ||
1418 | if (*len != sizeof(struct ip6t_getinfo)) { | |
1419 | duprintf("length %u != %u\n", *len, | |
1420 | sizeof(struct ip6t_getinfo)); | |
1421 | ret = -EINVAL; | |
1422 | break; | |
1423 | } | |
1424 | ||
1425 | if (copy_from_user(name, user, sizeof(name)) != 0) { | |
1426 | ret = -EFAULT; | |
1427 | break; | |
1428 | } | |
1429 | name[IP6T_TABLE_MAXNAMELEN-1] = '\0'; | |
6b7d31fc HW |
1430 | |
1431 | t = try_then_request_module(find_table_lock(name), | |
1432 | "ip6table_%s", name); | |
1433 | if (t && !IS_ERR(t)) { | |
1da177e4 LT |
1434 | struct ip6t_getinfo info; |
1435 | ||
1436 | info.valid_hooks = t->valid_hooks; | |
1437 | memcpy(info.hook_entry, t->private->hook_entry, | |
1438 | sizeof(info.hook_entry)); | |
1439 | memcpy(info.underflow, t->private->underflow, | |
1440 | sizeof(info.underflow)); | |
1441 | info.num_entries = t->private->number; | |
1442 | info.size = t->private->size; | |
1443 | memcpy(info.name, name, sizeof(info.name)); | |
1444 | ||
1445 | if (copy_to_user(user, &info, *len) != 0) | |
1446 | ret = -EFAULT; | |
1447 | else | |
1448 | ret = 0; | |
1da177e4 | 1449 | up(&ip6t_mutex); |
6b7d31fc HW |
1450 | module_put(t->me); |
1451 | } else | |
1452 | ret = t ? PTR_ERR(t) : -ENOENT; | |
1da177e4 LT |
1453 | } |
1454 | break; | |
1455 | ||
1456 | case IP6T_SO_GET_ENTRIES: { | |
1457 | struct ip6t_get_entries get; | |
1458 | ||
1459 | if (*len < sizeof(get)) { | |
1460 | duprintf("get_entries: %u < %u\n", *len, sizeof(get)); | |
1461 | ret = -EINVAL; | |
1462 | } else if (copy_from_user(&get, user, sizeof(get)) != 0) { | |
1463 | ret = -EFAULT; | |
1464 | } else if (*len != sizeof(struct ip6t_get_entries) + get.size) { | |
1465 | duprintf("get_entries: %u != %u\n", *len, | |
1466 | sizeof(struct ip6t_get_entries) + get.size); | |
1467 | ret = -EINVAL; | |
1468 | } else | |
1469 | ret = get_entries(&get, user); | |
1470 | break; | |
1471 | } | |
1472 | ||
6b7d31fc HW |
1473 | case IP6T_SO_GET_REVISION_MATCH: |
1474 | case IP6T_SO_GET_REVISION_TARGET: { | |
1475 | struct ip6t_get_revision rev; | |
1476 | int (*revfn)(const char *, u8, int *); | |
1477 | ||
1478 | if (*len != sizeof(rev)) { | |
1479 | ret = -EINVAL; | |
1480 | break; | |
1481 | } | |
1482 | if (copy_from_user(&rev, user, sizeof(rev)) != 0) { | |
1483 | ret = -EFAULT; | |
1484 | break; | |
1485 | } | |
1486 | ||
1487 | if (cmd == IP6T_SO_GET_REVISION_TARGET) | |
1488 | revfn = target_revfn; | |
1489 | else | |
1490 | revfn = match_revfn; | |
1491 | ||
1492 | try_then_request_module(find_revision(rev.name, rev.revision, | |
1493 | revfn, &ret), | |
1494 | "ip6t_%s", rev.name); | |
1495 | break; | |
1496 | } | |
1497 | ||
1da177e4 LT |
1498 | default: |
1499 | duprintf("do_ip6t_get_ctl: unknown request %i\n", cmd); | |
1500 | ret = -EINVAL; | |
1501 | } | |
1502 | ||
1503 | return ret; | |
1504 | } | |
1505 | ||
1506 | /* Registration hooks for targets. */ | |
1507 | int | |
1508 | ip6t_register_target(struct ip6t_target *target) | |
1509 | { | |
1510 | int ret; | |
1511 | ||
1512 | ret = down_interruptible(&ip6t_mutex); | |
1513 | if (ret != 0) | |
1514 | return ret; | |
6b7d31fc | 1515 | list_add(&target->list, &ip6t_target); |
1da177e4 LT |
1516 | up(&ip6t_mutex); |
1517 | return ret; | |
1518 | } | |
1519 | ||
1520 | void | |
1521 | ip6t_unregister_target(struct ip6t_target *target) | |
1522 | { | |
1523 | down(&ip6t_mutex); | |
1524 | LIST_DELETE(&ip6t_target, target); | |
1525 | up(&ip6t_mutex); | |
1526 | } | |
1527 | ||
1528 | int | |
1529 | ip6t_register_match(struct ip6t_match *match) | |
1530 | { | |
1531 | int ret; | |
1532 | ||
1533 | ret = down_interruptible(&ip6t_mutex); | |
1534 | if (ret != 0) | |
1535 | return ret; | |
1536 | ||
6b7d31fc | 1537 | list_add(&match->list, &ip6t_match); |
1da177e4 LT |
1538 | up(&ip6t_mutex); |
1539 | ||
1540 | return ret; | |
1541 | } | |
1542 | ||
1543 | void | |
1544 | ip6t_unregister_match(struct ip6t_match *match) | |
1545 | { | |
1546 | down(&ip6t_mutex); | |
1547 | LIST_DELETE(&ip6t_match, match); | |
1548 | up(&ip6t_mutex); | |
1549 | } | |
1550 | ||
1551 | int ip6t_register_table(struct ip6t_table *table, | |
1552 | const struct ip6t_replace *repl) | |
1553 | { | |
1554 | int ret; | |
1555 | struct ip6t_table_info *newinfo; | |
1556 | static struct ip6t_table_info bootstrap | |
1557 | = { 0, 0, 0, { 0 }, { 0 }, { } }; | |
31836064 | 1558 | void *loc_cpu_entry; |
1da177e4 | 1559 | |
31836064 | 1560 | newinfo = alloc_table_info(repl->size); |
1da177e4 LT |
1561 | if (!newinfo) |
1562 | return -ENOMEM; | |
1563 | ||
31836064 ED |
1564 | /* choose the copy on our node/cpu */ |
1565 | loc_cpu_entry = newinfo->entries[raw_smp_processor_id()]; | |
1566 | memcpy(loc_cpu_entry, repl->entries, repl->size); | |
1da177e4 LT |
1567 | |
1568 | ret = translate_table(table->name, table->valid_hooks, | |
31836064 | 1569 | newinfo, loc_cpu_entry, repl->size, |
1da177e4 LT |
1570 | repl->num_entries, |
1571 | repl->hook_entry, | |
1572 | repl->underflow); | |
1573 | if (ret != 0) { | |
31836064 | 1574 | free_table_info(newinfo); |
1da177e4 LT |
1575 | return ret; |
1576 | } | |
1577 | ||
1578 | ret = down_interruptible(&ip6t_mutex); | |
1579 | if (ret != 0) { | |
31836064 | 1580 | free_table_info(newinfo); |
1da177e4 LT |
1581 | return ret; |
1582 | } | |
1583 | ||
1584 | /* Don't autoload: we'd eat our tail... */ | |
1585 | if (list_named_find(&ip6t_tables, table->name)) { | |
1586 | ret = -EEXIST; | |
1587 | goto free_unlock; | |
1588 | } | |
1589 | ||
1590 | /* Simplifies replace_table code. */ | |
1591 | table->private = &bootstrap; | |
1592 | if (!replace_table(table, 0, newinfo, &ret)) | |
1593 | goto free_unlock; | |
1594 | ||
1595 | duprintf("table->private->number = %u\n", | |
1596 | table->private->number); | |
1597 | ||
1598 | /* save number of initial entries */ | |
1599 | table->private->initial_entries = table->private->number; | |
1600 | ||
1601 | rwlock_init(&table->lock); | |
1602 | list_prepend(&ip6t_tables, table); | |
1603 | ||
1604 | unlock: | |
1605 | up(&ip6t_mutex); | |
1606 | return ret; | |
1607 | ||
1608 | free_unlock: | |
31836064 | 1609 | free_table_info(newinfo); |
1da177e4 LT |
1610 | goto unlock; |
1611 | } | |
1612 | ||
1613 | void ip6t_unregister_table(struct ip6t_table *table) | |
1614 | { | |
31836064 ED |
1615 | void *loc_cpu_entry; |
1616 | ||
1da177e4 LT |
1617 | down(&ip6t_mutex); |
1618 | LIST_DELETE(&ip6t_tables, table); | |
1619 | up(&ip6t_mutex); | |
1620 | ||
1621 | /* Decrease module usage counts and free resources */ | |
31836064 ED |
1622 | loc_cpu_entry = table->private->entries[raw_smp_processor_id()]; |
1623 | IP6T_ENTRY_ITERATE(loc_cpu_entry, table->private->size, | |
1da177e4 | 1624 | cleanup_entry, NULL); |
31836064 | 1625 | free_table_info(table->private); |
1da177e4 LT |
1626 | } |
1627 | ||
1628 | /* Returns 1 if the port is matched by the range, 0 otherwise */ | |
1629 | static inline int | |
1630 | port_match(u_int16_t min, u_int16_t max, u_int16_t port, int invert) | |
1631 | { | |
1632 | int ret; | |
1633 | ||
1634 | ret = (port >= min && port <= max) ^ invert; | |
1635 | return ret; | |
1636 | } | |
1637 | ||
1638 | static int | |
1639 | tcp_find_option(u_int8_t option, | |
1640 | const struct sk_buff *skb, | |
1641 | unsigned int tcpoff, | |
1642 | unsigned int optlen, | |
1643 | int invert, | |
1644 | int *hotdrop) | |
1645 | { | |
1646 | /* tcp.doff is only 4 bits, ie. max 15 * 4 bytes */ | |
1647 | u_int8_t _opt[60 - sizeof(struct tcphdr)], *op; | |
1648 | unsigned int i; | |
1649 | ||
1650 | duprintf("tcp_match: finding option\n"); | |
1651 | if (!optlen) | |
1652 | return invert; | |
1653 | /* If we don't have the whole header, drop packet. */ | |
1654 | op = skb_header_pointer(skb, tcpoff + sizeof(struct tcphdr), optlen, | |
1655 | _opt); | |
1656 | if (op == NULL) { | |
1657 | *hotdrop = 1; | |
1658 | return 0; | |
1659 | } | |
1660 | ||
1661 | for (i = 0; i < optlen; ) { | |
1662 | if (op[i] == option) return !invert; | |
1663 | if (op[i] < 2) i++; | |
1664 | else i += op[i+1]?:1; | |
1665 | } | |
1666 | ||
1667 | return invert; | |
1668 | } | |
1669 | ||
1670 | static int | |
1671 | tcp_match(const struct sk_buff *skb, | |
1672 | const struct net_device *in, | |
1673 | const struct net_device *out, | |
1674 | const void *matchinfo, | |
1675 | int offset, | |
1676 | unsigned int protoff, | |
1677 | int *hotdrop) | |
1678 | { | |
1679 | struct tcphdr _tcph, *th; | |
1680 | const struct ip6t_tcp *tcpinfo = matchinfo; | |
1681 | ||
1682 | if (offset) { | |
1683 | /* To quote Alan: | |
1684 | ||
1685 | Don't allow a fragment of TCP 8 bytes in. Nobody normal | |
1686 | causes this. Its a cracker trying to break in by doing a | |
1687 | flag overwrite to pass the direction checks. | |
1688 | */ | |
1689 | if (offset == 1) { | |
1690 | duprintf("Dropping evil TCP offset=1 frag.\n"); | |
1691 | *hotdrop = 1; | |
1692 | } | |
1693 | /* Must not be a fragment. */ | |
1694 | return 0; | |
1695 | } | |
1696 | ||
1697 | #define FWINVTCP(bool,invflg) ((bool) ^ !!(tcpinfo->invflags & invflg)) | |
1698 | ||
1699 | th = skb_header_pointer(skb, protoff, sizeof(_tcph), &_tcph); | |
1700 | if (th == NULL) { | |
1701 | /* We've been asked to examine this packet, and we | |
1702 | can't. Hence, no choice but to drop. */ | |
1703 | duprintf("Dropping evil TCP offset=0 tinygram.\n"); | |
1704 | *hotdrop = 1; | |
1705 | return 0; | |
1706 | } | |
1707 | ||
1708 | if (!port_match(tcpinfo->spts[0], tcpinfo->spts[1], | |
1709 | ntohs(th->source), | |
1710 | !!(tcpinfo->invflags & IP6T_TCP_INV_SRCPT))) | |
1711 | return 0; | |
1712 | if (!port_match(tcpinfo->dpts[0], tcpinfo->dpts[1], | |
1713 | ntohs(th->dest), | |
1714 | !!(tcpinfo->invflags & IP6T_TCP_INV_DSTPT))) | |
1715 | return 0; | |
1716 | if (!FWINVTCP((((unsigned char *)th)[13] & tcpinfo->flg_mask) | |
1717 | == tcpinfo->flg_cmp, | |
1718 | IP6T_TCP_INV_FLAGS)) | |
1719 | return 0; | |
1720 | if (tcpinfo->option) { | |
1721 | if (th->doff * 4 < sizeof(_tcph)) { | |
1722 | *hotdrop = 1; | |
1723 | return 0; | |
1724 | } | |
1725 | if (!tcp_find_option(tcpinfo->option, skb, protoff, | |
1726 | th->doff*4 - sizeof(*th), | |
1727 | tcpinfo->invflags & IP6T_TCP_INV_OPTION, | |
1728 | hotdrop)) | |
1729 | return 0; | |
1730 | } | |
1731 | return 1; | |
1732 | } | |
1733 | ||
1734 | /* Called when user tries to insert an entry of this type. */ | |
1735 | static int | |
1736 | tcp_checkentry(const char *tablename, | |
1737 | const struct ip6t_ip6 *ipv6, | |
1738 | void *matchinfo, | |
1739 | unsigned int matchsize, | |
1740 | unsigned int hook_mask) | |
1741 | { | |
1742 | const struct ip6t_tcp *tcpinfo = matchinfo; | |
1743 | ||
1744 | /* Must specify proto == TCP, and no unknown invflags */ | |
1745 | return ipv6->proto == IPPROTO_TCP | |
1746 | && !(ipv6->invflags & IP6T_INV_PROTO) | |
1747 | && matchsize == IP6T_ALIGN(sizeof(struct ip6t_tcp)) | |
1748 | && !(tcpinfo->invflags & ~IP6T_TCP_INV_MASK); | |
1749 | } | |
1750 | ||
1751 | static int | |
1752 | udp_match(const struct sk_buff *skb, | |
1753 | const struct net_device *in, | |
1754 | const struct net_device *out, | |
1755 | const void *matchinfo, | |
1756 | int offset, | |
1757 | unsigned int protoff, | |
1758 | int *hotdrop) | |
1759 | { | |
1760 | struct udphdr _udph, *uh; | |
1761 | const struct ip6t_udp *udpinfo = matchinfo; | |
1762 | ||
1763 | /* Must not be a fragment. */ | |
1764 | if (offset) | |
1765 | return 0; | |
1766 | ||
1767 | uh = skb_header_pointer(skb, protoff, sizeof(_udph), &_udph); | |
1768 | if (uh == NULL) { | |
1769 | /* We've been asked to examine this packet, and we | |
1770 | can't. Hence, no choice but to drop. */ | |
1771 | duprintf("Dropping evil UDP tinygram.\n"); | |
1772 | *hotdrop = 1; | |
1773 | return 0; | |
1774 | } | |
1775 | ||
1776 | return port_match(udpinfo->spts[0], udpinfo->spts[1], | |
1777 | ntohs(uh->source), | |
1778 | !!(udpinfo->invflags & IP6T_UDP_INV_SRCPT)) | |
1779 | && port_match(udpinfo->dpts[0], udpinfo->dpts[1], | |
1780 | ntohs(uh->dest), | |
1781 | !!(udpinfo->invflags & IP6T_UDP_INV_DSTPT)); | |
1782 | } | |
1783 | ||
1784 | /* Called when user tries to insert an entry of this type. */ | |
1785 | static int | |
1786 | udp_checkentry(const char *tablename, | |
1787 | const struct ip6t_ip6 *ipv6, | |
1788 | void *matchinfo, | |
1789 | unsigned int matchinfosize, | |
1790 | unsigned int hook_mask) | |
1791 | { | |
1792 | const struct ip6t_udp *udpinfo = matchinfo; | |
1793 | ||
1794 | /* Must specify proto == UDP, and no unknown invflags */ | |
1795 | if (ipv6->proto != IPPROTO_UDP || (ipv6->invflags & IP6T_INV_PROTO)) { | |
1796 | duprintf("ip6t_udp: Protocol %u != %u\n", ipv6->proto, | |
1797 | IPPROTO_UDP); | |
1798 | return 0; | |
1799 | } | |
1800 | if (matchinfosize != IP6T_ALIGN(sizeof(struct ip6t_udp))) { | |
1801 | duprintf("ip6t_udp: matchsize %u != %u\n", | |
1802 | matchinfosize, IP6T_ALIGN(sizeof(struct ip6t_udp))); | |
1803 | return 0; | |
1804 | } | |
1805 | if (udpinfo->invflags & ~IP6T_UDP_INV_MASK) { | |
1806 | duprintf("ip6t_udp: unknown flags %X\n", | |
1807 | udpinfo->invflags); | |
1808 | return 0; | |
1809 | } | |
1810 | ||
1811 | return 1; | |
1812 | } | |
1813 | ||
1814 | /* Returns 1 if the type and code is matched by the range, 0 otherwise */ | |
1815 | static inline int | |
1816 | icmp6_type_code_match(u_int8_t test_type, u_int8_t min_code, u_int8_t max_code, | |
1817 | u_int8_t type, u_int8_t code, | |
1818 | int invert) | |
1819 | { | |
1820 | return (type == test_type && code >= min_code && code <= max_code) | |
1821 | ^ invert; | |
1822 | } | |
1823 | ||
1824 | static int | |
1825 | icmp6_match(const struct sk_buff *skb, | |
1826 | const struct net_device *in, | |
1827 | const struct net_device *out, | |
1828 | const void *matchinfo, | |
1829 | int offset, | |
1830 | unsigned int protoff, | |
1831 | int *hotdrop) | |
1832 | { | |
1833 | struct icmp6hdr _icmp, *ic; | |
1834 | const struct ip6t_icmp *icmpinfo = matchinfo; | |
1835 | ||
1836 | /* Must not be a fragment. */ | |
1837 | if (offset) | |
1838 | return 0; | |
1839 | ||
1840 | ic = skb_header_pointer(skb, protoff, sizeof(_icmp), &_icmp); | |
1841 | if (ic == NULL) { | |
1842 | /* We've been asked to examine this packet, and we | |
1843 | can't. Hence, no choice but to drop. */ | |
1844 | duprintf("Dropping evil ICMP tinygram.\n"); | |
1845 | *hotdrop = 1; | |
1846 | return 0; | |
1847 | } | |
1848 | ||
1849 | return icmp6_type_code_match(icmpinfo->type, | |
1850 | icmpinfo->code[0], | |
1851 | icmpinfo->code[1], | |
1852 | ic->icmp6_type, ic->icmp6_code, | |
1853 | !!(icmpinfo->invflags&IP6T_ICMP_INV)); | |
1854 | } | |
1855 | ||
1856 | /* Called when user tries to insert an entry of this type. */ | |
1857 | static int | |
1858 | icmp6_checkentry(const char *tablename, | |
1859 | const struct ip6t_ip6 *ipv6, | |
1860 | void *matchinfo, | |
1861 | unsigned int matchsize, | |
1862 | unsigned int hook_mask) | |
1863 | { | |
1864 | const struct ip6t_icmp *icmpinfo = matchinfo; | |
1865 | ||
1866 | /* Must specify proto == ICMP, and no unknown invflags */ | |
1867 | return ipv6->proto == IPPROTO_ICMPV6 | |
1868 | && !(ipv6->invflags & IP6T_INV_PROTO) | |
1869 | && matchsize == IP6T_ALIGN(sizeof(struct ip6t_icmp)) | |
1870 | && !(icmpinfo->invflags & ~IP6T_ICMP_INV); | |
1871 | } | |
1872 | ||
1873 | /* The built-in targets: standard (NULL) and error. */ | |
1874 | static struct ip6t_target ip6t_standard_target = { | |
1875 | .name = IP6T_STANDARD_TARGET, | |
1876 | }; | |
1877 | ||
1878 | static struct ip6t_target ip6t_error_target = { | |
1879 | .name = IP6T_ERROR_TARGET, | |
1880 | .target = ip6t_error, | |
1881 | }; | |
1882 | ||
1883 | static struct nf_sockopt_ops ip6t_sockopts = { | |
1884 | .pf = PF_INET6, | |
1885 | .set_optmin = IP6T_BASE_CTL, | |
1886 | .set_optmax = IP6T_SO_SET_MAX+1, | |
1887 | .set = do_ip6t_set_ctl, | |
1888 | .get_optmin = IP6T_BASE_CTL, | |
1889 | .get_optmax = IP6T_SO_GET_MAX+1, | |
1890 | .get = do_ip6t_get_ctl, | |
1891 | }; | |
1892 | ||
1893 | static struct ip6t_match tcp_matchstruct = { | |
1894 | .name = "tcp", | |
1895 | .match = &tcp_match, | |
1896 | .checkentry = &tcp_checkentry, | |
1897 | }; | |
1898 | ||
1899 | static struct ip6t_match udp_matchstruct = { | |
1900 | .name = "udp", | |
1901 | .match = &udp_match, | |
1902 | .checkentry = &udp_checkentry, | |
1903 | }; | |
1904 | ||
1905 | static struct ip6t_match icmp6_matchstruct = { | |
1906 | .name = "icmp6", | |
1907 | .match = &icmp6_match, | |
1908 | .checkentry = &icmp6_checkentry, | |
1909 | }; | |
1910 | ||
1911 | #ifdef CONFIG_PROC_FS | |
1912 | static inline int print_name(const char *i, | |
1913 | off_t start_offset, char *buffer, int length, | |
1914 | off_t *pos, unsigned int *count) | |
1915 | { | |
1916 | if ((*count)++ >= start_offset) { | |
1917 | unsigned int namelen; | |
1918 | ||
1919 | namelen = sprintf(buffer + *pos, "%s\n", | |
1920 | i + sizeof(struct list_head)); | |
1921 | if (*pos + namelen > length) { | |
1922 | /* Stop iterating */ | |
1923 | return 1; | |
1924 | } | |
1925 | *pos += namelen; | |
1926 | } | |
1927 | return 0; | |
1928 | } | |
1929 | ||
1930 | static inline int print_target(const struct ip6t_target *t, | |
1931 | off_t start_offset, char *buffer, int length, | |
1932 | off_t *pos, unsigned int *count) | |
1933 | { | |
1934 | if (t == &ip6t_standard_target || t == &ip6t_error_target) | |
1935 | return 0; | |
1936 | return print_name((char *)t, start_offset, buffer, length, pos, count); | |
1937 | } | |
1938 | ||
1939 | static int ip6t_get_tables(char *buffer, char **start, off_t offset, int length) | |
1940 | { | |
1941 | off_t pos = 0; | |
1942 | unsigned int count = 0; | |
1943 | ||
1944 | if (down_interruptible(&ip6t_mutex) != 0) | |
1945 | return 0; | |
1946 | ||
1947 | LIST_FIND(&ip6t_tables, print_name, char *, | |
1948 | offset, buffer, length, &pos, &count); | |
1949 | ||
1950 | up(&ip6t_mutex); | |
1951 | ||
1952 | /* `start' hack - see fs/proc/generic.c line ~105 */ | |
1953 | *start=(char *)((unsigned long)count-offset); | |
1954 | return pos; | |
1955 | } | |
1956 | ||
1957 | static int ip6t_get_targets(char *buffer, char **start, off_t offset, int length) | |
1958 | { | |
1959 | off_t pos = 0; | |
1960 | unsigned int count = 0; | |
1961 | ||
1962 | if (down_interruptible(&ip6t_mutex) != 0) | |
1963 | return 0; | |
1964 | ||
1965 | LIST_FIND(&ip6t_target, print_target, struct ip6t_target *, | |
1966 | offset, buffer, length, &pos, &count); | |
1967 | ||
1968 | up(&ip6t_mutex); | |
1969 | ||
1970 | *start = (char *)((unsigned long)count - offset); | |
1971 | return pos; | |
1972 | } | |
1973 | ||
1974 | static int ip6t_get_matches(char *buffer, char **start, off_t offset, int length) | |
1975 | { | |
1976 | off_t pos = 0; | |
1977 | unsigned int count = 0; | |
1978 | ||
1979 | if (down_interruptible(&ip6t_mutex) != 0) | |
1980 | return 0; | |
1981 | ||
1982 | LIST_FIND(&ip6t_match, print_name, char *, | |
1983 | offset, buffer, length, &pos, &count); | |
1984 | ||
1985 | up(&ip6t_mutex); | |
1986 | ||
1987 | *start = (char *)((unsigned long)count - offset); | |
1988 | return pos; | |
1989 | } | |
1990 | ||
9b5b5cff | 1991 | static const struct { char *name; get_info_t *get_info; } ip6t_proc_entry[] = |
1da177e4 LT |
1992 | { { "ip6_tables_names", ip6t_get_tables }, |
1993 | { "ip6_tables_targets", ip6t_get_targets }, | |
1994 | { "ip6_tables_matches", ip6t_get_matches }, | |
1995 | { NULL, NULL} }; | |
1996 | #endif /*CONFIG_PROC_FS*/ | |
1997 | ||
1998 | static int __init init(void) | |
1999 | { | |
2000 | int ret; | |
2001 | ||
2002 | /* Noone else will be downing sem now, so we won't sleep */ | |
2003 | down(&ip6t_mutex); | |
2004 | list_append(&ip6t_target, &ip6t_standard_target); | |
2005 | list_append(&ip6t_target, &ip6t_error_target); | |
2006 | list_append(&ip6t_match, &tcp_matchstruct); | |
2007 | list_append(&ip6t_match, &udp_matchstruct); | |
2008 | list_append(&ip6t_match, &icmp6_matchstruct); | |
2009 | up(&ip6t_mutex); | |
2010 | ||
2011 | /* Register setsockopt */ | |
2012 | ret = nf_register_sockopt(&ip6t_sockopts); | |
2013 | if (ret < 0) { | |
2014 | duprintf("Unable to register sockopts.\n"); | |
2015 | return ret; | |
2016 | } | |
2017 | ||
2018 | #ifdef CONFIG_PROC_FS | |
2019 | { | |
2020 | struct proc_dir_entry *proc; | |
2021 | int i; | |
2022 | ||
2023 | for (i = 0; ip6t_proc_entry[i].name; i++) { | |
2024 | proc = proc_net_create(ip6t_proc_entry[i].name, 0, | |
2025 | ip6t_proc_entry[i].get_info); | |
2026 | if (!proc) { | |
2027 | while (--i >= 0) | |
2028 | proc_net_remove(ip6t_proc_entry[i].name); | |
2029 | nf_unregister_sockopt(&ip6t_sockopts); | |
2030 | return -ENOMEM; | |
2031 | } | |
2032 | proc->owner = THIS_MODULE; | |
2033 | } | |
2034 | } | |
2035 | #endif | |
2036 | ||
2037 | printk("ip6_tables: (C) 2000-2002 Netfilter core team\n"); | |
2038 | return 0; | |
2039 | } | |
2040 | ||
2041 | static void __exit fini(void) | |
2042 | { | |
2043 | nf_unregister_sockopt(&ip6t_sockopts); | |
2044 | #ifdef CONFIG_PROC_FS | |
2045 | { | |
2046 | int i; | |
2047 | for (i = 0; ip6t_proc_entry[i].name; i++) | |
2048 | proc_net_remove(ip6t_proc_entry[i].name); | |
2049 | } | |
2050 | #endif | |
2051 | } | |
2052 | ||
e674d0f3 | 2053 | /* |
b777e0ce PM |
2054 | * find the offset to specified header or the protocol number of last header |
2055 | * if target < 0. "last header" is transport protocol header, ESP, or | |
2056 | * "No next header". | |
2057 | * | |
2058 | * If target header is found, its offset is set in *offset and return protocol | |
2059 | * number. Otherwise, return -1. | |
2060 | * | |
2061 | * Note that non-1st fragment is special case that "the protocol number | |
2062 | * of last header" is "next header" field in Fragment header. In this case, | |
2063 | * *offset is meaningless and fragment offset is stored in *fragoff if fragoff | |
2064 | * isn't NULL. | |
e674d0f3 | 2065 | * |
e674d0f3 | 2066 | */ |
b777e0ce PM |
2067 | int ipv6_find_hdr(const struct sk_buff *skb, unsigned int *offset, |
2068 | int target, unsigned short *fragoff) | |
e674d0f3 YK |
2069 | { |
2070 | unsigned int start = (u8*)(skb->nh.ipv6h + 1) - skb->data; | |
2071 | u8 nexthdr = skb->nh.ipv6h->nexthdr; | |
2072 | unsigned int len = skb->len - start; | |
2073 | ||
b777e0ce PM |
2074 | if (fragoff) |
2075 | *fragoff = 0; | |
2076 | ||
e674d0f3 YK |
2077 | while (nexthdr != target) { |
2078 | struct ipv6_opt_hdr _hdr, *hp; | |
2079 | unsigned int hdrlen; | |
2080 | ||
b777e0ce PM |
2081 | if ((!ipv6_ext_hdr(nexthdr)) || nexthdr == NEXTHDR_NONE) { |
2082 | if (target < 0) | |
2083 | break; | |
e674d0f3 | 2084 | return -1; |
b777e0ce PM |
2085 | } |
2086 | ||
e674d0f3 YK |
2087 | hp = skb_header_pointer(skb, start, sizeof(_hdr), &_hdr); |
2088 | if (hp == NULL) | |
2089 | return -1; | |
2090 | if (nexthdr == NEXTHDR_FRAGMENT) { | |
2091 | unsigned short _frag_off, *fp; | |
2092 | fp = skb_header_pointer(skb, | |
2093 | start+offsetof(struct frag_hdr, | |
2094 | frag_off), | |
2095 | sizeof(_frag_off), | |
2096 | &_frag_off); | |
2097 | if (fp == NULL) | |
2098 | return -1; | |
2099 | ||
b777e0ce PM |
2100 | _frag_off = ntohs(*fp) & ~0x7; |
2101 | if (_frag_off) { | |
2102 | if (target < 0 && | |
2103 | ((!ipv6_ext_hdr(hp->nexthdr)) || | |
2104 | nexthdr == NEXTHDR_NONE)) { | |
2105 | if (fragoff) | |
2106 | *fragoff = _frag_off; | |
2107 | return hp->nexthdr; | |
2108 | } | |
e674d0f3 | 2109 | return -1; |
b777e0ce | 2110 | } |
e674d0f3 YK |
2111 | hdrlen = 8; |
2112 | } else if (nexthdr == NEXTHDR_AUTH) | |
2113 | hdrlen = (hp->hdrlen + 2) << 2; | |
2114 | else | |
2115 | hdrlen = ipv6_optlen(hp); | |
2116 | ||
2117 | nexthdr = hp->nexthdr; | |
2118 | len -= hdrlen; | |
2119 | start += hdrlen; | |
2120 | } | |
2121 | ||
2122 | *offset = start; | |
b777e0ce | 2123 | return nexthdr; |
e674d0f3 YK |
2124 | } |
2125 | ||
1da177e4 LT |
2126 | EXPORT_SYMBOL(ip6t_register_table); |
2127 | EXPORT_SYMBOL(ip6t_unregister_table); | |
2128 | EXPORT_SYMBOL(ip6t_do_table); | |
2129 | EXPORT_SYMBOL(ip6t_register_match); | |
2130 | EXPORT_SYMBOL(ip6t_unregister_match); | |
2131 | EXPORT_SYMBOL(ip6t_register_target); | |
2132 | EXPORT_SYMBOL(ip6t_unregister_target); | |
2133 | EXPORT_SYMBOL(ip6t_ext_hdr); | |
e674d0f3 | 2134 | EXPORT_SYMBOL(ipv6_find_hdr); |
22dea562 | 2135 | EXPORT_SYMBOL(ip6_masked_addrcmp); |
1da177e4 LT |
2136 | |
2137 | module_init(init); | |
2138 | module_exit(fini); |