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Commit | Line | Data |
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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. | |
1da177e4 | 10 | */ |
4fc268d2 RD |
11 | |
12 | #include <linux/capability.h> | |
14c85021 | 13 | #include <linux/in.h> |
1da177e4 LT |
14 | #include <linux/skbuff.h> |
15 | #include <linux/kmod.h> | |
16 | #include <linux/vmalloc.h> | |
17 | #include <linux/netdevice.h> | |
18 | #include <linux/module.h> | |
4bdbf6c0 | 19 | #include <linux/poison.h> |
1da177e4 | 20 | #include <linux/icmpv6.h> |
1da177e4 LT |
21 | #include <net/ipv6.h> |
22 | #include <asm/uaccess.h> | |
57b47a53 | 23 | #include <linux/mutex.h> |
1da177e4 | 24 | #include <linux/proc_fs.h> |
c8923c6b | 25 | #include <linux/cpumask.h> |
1da177e4 LT |
26 | |
27 | #include <linux/netfilter_ipv6/ip6_tables.h> | |
2e4e6a17 | 28 | #include <linux/netfilter/x_tables.h> |
1da177e4 LT |
29 | |
30 | MODULE_LICENSE("GPL"); | |
31 | MODULE_AUTHOR("Netfilter Core Team <coreteam@netfilter.org>"); | |
32 | MODULE_DESCRIPTION("IPv6 packet filter"); | |
33 | ||
34 | #define IPV6_HDR_LEN (sizeof(struct ipv6hdr)) | |
35 | #define IPV6_OPTHDR_LEN (sizeof(struct ipv6_opt_hdr)) | |
36 | ||
37 | /*#define DEBUG_IP_FIREWALL*/ | |
38 | /*#define DEBUG_ALLOW_ALL*/ /* Useful for remote debugging */ | |
39 | /*#define DEBUG_IP_FIREWALL_USER*/ | |
40 | ||
41 | #ifdef DEBUG_IP_FIREWALL | |
42 | #define dprintf(format, args...) printk(format , ## args) | |
43 | #else | |
44 | #define dprintf(format, args...) | |
45 | #endif | |
46 | ||
47 | #ifdef DEBUG_IP_FIREWALL_USER | |
48 | #define duprintf(format, args...) printk(format , ## args) | |
49 | #else | |
50 | #define duprintf(format, args...) | |
51 | #endif | |
52 | ||
53 | #ifdef CONFIG_NETFILTER_DEBUG | |
54 | #define IP_NF_ASSERT(x) \ | |
55 | do { \ | |
56 | if (!(x)) \ | |
57 | printk("IP_NF_ASSERT: %s:%s:%u\n", \ | |
58 | __FUNCTION__, __FILE__, __LINE__); \ | |
59 | } while(0) | |
60 | #else | |
61 | #define IP_NF_ASSERT(x) | |
62 | #endif | |
1da177e4 | 63 | |
1da177e4 LT |
64 | #if 0 |
65 | /* All the better to debug you with... */ | |
66 | #define static | |
67 | #define inline | |
68 | #endif | |
69 | ||
6b7d31fc | 70 | /* |
1da177e4 | 71 | We keep a set of rules for each CPU, so we can avoid write-locking |
6b7d31fc HW |
72 | them in the softirq when updating the counters and therefore |
73 | only need to read-lock in the softirq; doing a write_lock_bh() in user | |
74 | context stops packets coming through and allows user context to read | |
75 | the counters or update the rules. | |
1da177e4 | 76 | |
1da177e4 LT |
77 | Hence the start of any table is given by get_table() below. */ |
78 | ||
1da177e4 LT |
79 | #if 0 |
80 | #define down(x) do { printk("DOWN:%u:" #x "\n", __LINE__); down(x); } while(0) | |
81 | #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; }) | |
82 | #define up(x) do { printk("UP:%u:" #x "\n", __LINE__); up(x); } while(0) | |
83 | #endif | |
84 | ||
1da177e4 | 85 | /* Check for an extension */ |
1ab1457c | 86 | int |
1da177e4 LT |
87 | ip6t_ext_hdr(u8 nexthdr) |
88 | { | |
1ab1457c YH |
89 | return ( (nexthdr == IPPROTO_HOPOPTS) || |
90 | (nexthdr == IPPROTO_ROUTING) || | |
91 | (nexthdr == IPPROTO_FRAGMENT) || | |
92 | (nexthdr == IPPROTO_ESP) || | |
93 | (nexthdr == IPPROTO_AH) || | |
94 | (nexthdr == IPPROTO_NONE) || | |
95 | (nexthdr == IPPROTO_DSTOPTS) ); | |
1da177e4 LT |
96 | } |
97 | ||
98 | /* Returns whether matches rule or not. */ | |
1d93a9cb | 99 | static inline bool |
1da177e4 LT |
100 | ip6_packet_match(const struct sk_buff *skb, |
101 | const char *indev, | |
102 | const char *outdev, | |
103 | const struct ip6t_ip6 *ip6info, | |
104 | unsigned int *protoff, | |
cff533ac | 105 | int *fragoff, bool *hotdrop) |
1da177e4 LT |
106 | { |
107 | size_t i; | |
108 | unsigned long ret; | |
0660e03f | 109 | const struct ipv6hdr *ipv6 = ipv6_hdr(skb); |
1da177e4 LT |
110 | |
111 | #define FWINV(bool,invflg) ((bool) ^ !!(ip6info->invflags & invflg)) | |
112 | ||
f2ffd9ee | 113 | if (FWINV(ipv6_masked_addr_cmp(&ipv6->saddr, &ip6info->smsk, |
1ab1457c | 114 | &ip6info->src), IP6T_INV_SRCIP) |
f2ffd9ee | 115 | || FWINV(ipv6_masked_addr_cmp(&ipv6->daddr, &ip6info->dmsk, |
1ab1457c | 116 | &ip6info->dst), IP6T_INV_DSTIP)) { |
1da177e4 LT |
117 | dprintf("Source or dest mismatch.\n"); |
118 | /* | |
119 | dprintf("SRC: %u. Mask: %u. Target: %u.%s\n", ip->saddr, | |
120 | ipinfo->smsk.s_addr, ipinfo->src.s_addr, | |
121 | ipinfo->invflags & IP6T_INV_SRCIP ? " (INV)" : ""); | |
122 | dprintf("DST: %u. Mask: %u. Target: %u.%s\n", ip->daddr, | |
123 | ipinfo->dmsk.s_addr, ipinfo->dst.s_addr, | |
124 | ipinfo->invflags & IP6T_INV_DSTIP ? " (INV)" : "");*/ | |
1d93a9cb | 125 | return false; |
1da177e4 LT |
126 | } |
127 | ||
128 | /* Look for ifname matches; this should unroll nicely. */ | |
129 | for (i = 0, ret = 0; i < IFNAMSIZ/sizeof(unsigned long); i++) { | |
130 | ret |= (((const unsigned long *)indev)[i] | |
131 | ^ ((const unsigned long *)ip6info->iniface)[i]) | |
132 | & ((const unsigned long *)ip6info->iniface_mask)[i]; | |
133 | } | |
134 | ||
135 | if (FWINV(ret != 0, IP6T_INV_VIA_IN)) { | |
136 | dprintf("VIA in mismatch (%s vs %s).%s\n", | |
137 | indev, ip6info->iniface, | |
138 | ip6info->invflags&IP6T_INV_VIA_IN ?" (INV)":""); | |
1d93a9cb | 139 | return false; |
1da177e4 LT |
140 | } |
141 | ||
142 | for (i = 0, ret = 0; i < IFNAMSIZ/sizeof(unsigned long); i++) { | |
143 | ret |= (((const unsigned long *)outdev)[i] | |
144 | ^ ((const unsigned long *)ip6info->outiface)[i]) | |
145 | & ((const unsigned long *)ip6info->outiface_mask)[i]; | |
146 | } | |
147 | ||
148 | if (FWINV(ret != 0, IP6T_INV_VIA_OUT)) { | |
149 | dprintf("VIA out mismatch (%s vs %s).%s\n", | |
150 | outdev, ip6info->outiface, | |
151 | ip6info->invflags&IP6T_INV_VIA_OUT ?" (INV)":""); | |
1d93a9cb | 152 | return false; |
1da177e4 LT |
153 | } |
154 | ||
155 | /* ... might want to do something with class and flowlabel here ... */ | |
156 | ||
157 | /* look for the desired protocol header */ | |
158 | if((ip6info->flags & IP6T_F_PROTO)) { | |
b777e0ce PM |
159 | int protohdr; |
160 | unsigned short _frag_off; | |
1da177e4 | 161 | |
b777e0ce | 162 | protohdr = ipv6_find_hdr(skb, protoff, -1, &_frag_off); |
51d8b1a6 PM |
163 | if (protohdr < 0) { |
164 | if (_frag_off == 0) | |
cff533ac | 165 | *hotdrop = true; |
1d93a9cb | 166 | return false; |
51d8b1a6 | 167 | } |
b777e0ce | 168 | *fragoff = _frag_off; |
1da177e4 LT |
169 | |
170 | dprintf("Packet protocol %hi ?= %s%hi.\n", | |
1ab1457c | 171 | protohdr, |
1da177e4 LT |
172 | ip6info->invflags & IP6T_INV_PROTO ? "!":"", |
173 | ip6info->proto); | |
174 | ||
b777e0ce | 175 | if (ip6info->proto == protohdr) { |
1da177e4 | 176 | if(ip6info->invflags & IP6T_INV_PROTO) { |
1d93a9cb | 177 | return false; |
1da177e4 | 178 | } |
1d93a9cb | 179 | return true; |
1da177e4 LT |
180 | } |
181 | ||
182 | /* We need match for the '-p all', too! */ | |
183 | if ((ip6info->proto != 0) && | |
184 | !(ip6info->invflags & IP6T_INV_PROTO)) | |
1d93a9cb | 185 | return false; |
1da177e4 | 186 | } |
1d93a9cb | 187 | return true; |
1da177e4 LT |
188 | } |
189 | ||
190 | /* should be ip6 safe */ | |
ccb79bdc | 191 | static inline bool |
1da177e4 LT |
192 | ip6_checkentry(const struct ip6t_ip6 *ipv6) |
193 | { | |
194 | if (ipv6->flags & ~IP6T_F_MASK) { | |
195 | duprintf("Unknown flag bits set: %08X\n", | |
196 | ipv6->flags & ~IP6T_F_MASK); | |
ccb79bdc | 197 | return false; |
1da177e4 LT |
198 | } |
199 | if (ipv6->invflags & ~IP6T_INV_MASK) { | |
200 | duprintf("Unknown invflag bits set: %08X\n", | |
201 | ipv6->invflags & ~IP6T_INV_MASK); | |
ccb79bdc | 202 | return false; |
1da177e4 | 203 | } |
ccb79bdc | 204 | return true; |
1da177e4 LT |
205 | } |
206 | ||
207 | static unsigned int | |
3db05fea | 208 | ip6t_error(struct sk_buff *skb, |
1da177e4 LT |
209 | const struct net_device *in, |
210 | const struct net_device *out, | |
211 | unsigned int hooknum, | |
c4986734 | 212 | const struct xt_target *target, |
fe1cb108 | 213 | const void *targinfo) |
1da177e4 LT |
214 | { |
215 | if (net_ratelimit()) | |
216 | printk("ip6_tables: error: `%s'\n", (char *)targinfo); | |
217 | ||
218 | return NF_DROP; | |
219 | } | |
220 | ||
221 | static inline | |
1d93a9cb JE |
222 | bool do_match(struct ip6t_entry_match *m, |
223 | const struct sk_buff *skb, | |
224 | const struct net_device *in, | |
225 | const struct net_device *out, | |
226 | int offset, | |
227 | unsigned int protoff, | |
228 | bool *hotdrop) | |
1da177e4 LT |
229 | { |
230 | /* Stop iteration if it doesn't match */ | |
1c524830 | 231 | if (!m->u.kernel.match->match(skb, in, out, m->u.kernel.match, m->data, |
1da177e4 | 232 | offset, protoff, hotdrop)) |
1d93a9cb | 233 | return true; |
1da177e4 | 234 | else |
1d93a9cb | 235 | return false; |
1da177e4 LT |
236 | } |
237 | ||
238 | static inline struct ip6t_entry * | |
239 | get_entry(void *base, unsigned int offset) | |
240 | { | |
241 | return (struct ip6t_entry *)(base + offset); | |
242 | } | |
243 | ||
ba9dda3a JK |
244 | /* All zeroes == unconditional rule. */ |
245 | static inline int | |
246 | unconditional(const struct ip6t_ip6 *ipv6) | |
247 | { | |
248 | unsigned int i; | |
249 | ||
250 | for (i = 0; i < sizeof(*ipv6); i++) | |
251 | if (((char *)ipv6)[i]) | |
252 | break; | |
253 | ||
254 | return (i == sizeof(*ipv6)); | |
255 | } | |
256 | ||
257 | #if defined(CONFIG_NETFILTER_XT_TARGET_TRACE) || \ | |
258 | defined(CONFIG_NETFILTER_XT_TARGET_TRACE_MODULE) | |
259 | /* This cries for unification! */ | |
260 | static const char *hooknames[] = { | |
261 | [NF_IP6_PRE_ROUTING] = "PREROUTING", | |
262 | [NF_IP6_LOCAL_IN] = "INPUT", | |
263 | [NF_IP6_FORWARD] = "FORWARD", | |
264 | [NF_IP6_LOCAL_OUT] = "OUTPUT", | |
265 | [NF_IP6_POST_ROUTING] = "POSTROUTING", | |
266 | }; | |
267 | ||
268 | enum nf_ip_trace_comments { | |
269 | NF_IP6_TRACE_COMMENT_RULE, | |
270 | NF_IP6_TRACE_COMMENT_RETURN, | |
271 | NF_IP6_TRACE_COMMENT_POLICY, | |
272 | }; | |
273 | ||
274 | static const char *comments[] = { | |
275 | [NF_IP6_TRACE_COMMENT_RULE] = "rule", | |
276 | [NF_IP6_TRACE_COMMENT_RETURN] = "return", | |
277 | [NF_IP6_TRACE_COMMENT_POLICY] = "policy", | |
278 | }; | |
279 | ||
280 | static struct nf_loginfo trace_loginfo = { | |
281 | .type = NF_LOG_TYPE_LOG, | |
282 | .u = { | |
283 | .log = { | |
284 | .level = 4, | |
285 | .logflags = NF_LOG_MASK, | |
286 | }, | |
287 | }, | |
288 | }; | |
289 | ||
290 | static inline int | |
291 | get_chainname_rulenum(struct ip6t_entry *s, struct ip6t_entry *e, | |
292 | char *hookname, char **chainname, | |
293 | char **comment, unsigned int *rulenum) | |
294 | { | |
295 | struct ip6t_standard_target *t = (void *)ip6t_get_target(s); | |
296 | ||
297 | if (strcmp(t->target.u.kernel.target->name, IP6T_ERROR_TARGET) == 0) { | |
298 | /* Head of user chain: ERROR target with chainname */ | |
299 | *chainname = t->target.data; | |
300 | (*rulenum) = 0; | |
301 | } else if (s == e) { | |
302 | (*rulenum)++; | |
303 | ||
304 | if (s->target_offset == sizeof(struct ip6t_entry) | |
305 | && strcmp(t->target.u.kernel.target->name, | |
306 | IP6T_STANDARD_TARGET) == 0 | |
307 | && t->verdict < 0 | |
308 | && unconditional(&s->ipv6)) { | |
309 | /* Tail of chains: STANDARD target (return/policy) */ | |
310 | *comment = *chainname == hookname | |
311 | ? (char *)comments[NF_IP6_TRACE_COMMENT_POLICY] | |
312 | : (char *)comments[NF_IP6_TRACE_COMMENT_RETURN]; | |
313 | } | |
314 | return 1; | |
315 | } else | |
316 | (*rulenum)++; | |
317 | ||
318 | return 0; | |
319 | } | |
320 | ||
321 | static void trace_packet(struct sk_buff *skb, | |
322 | unsigned int hook, | |
323 | const struct net_device *in, | |
324 | const struct net_device *out, | |
325 | char *tablename, | |
326 | struct xt_table_info *private, | |
327 | struct ip6t_entry *e) | |
328 | { | |
329 | void *table_base; | |
330 | struct ip6t_entry *root; | |
331 | char *hookname, *chainname, *comment; | |
332 | unsigned int rulenum = 0; | |
333 | ||
334 | table_base = (void *)private->entries[smp_processor_id()]; | |
335 | root = get_entry(table_base, private->hook_entry[hook]); | |
336 | ||
337 | hookname = chainname = (char *)hooknames[hook]; | |
338 | comment = (char *)comments[NF_IP6_TRACE_COMMENT_RULE]; | |
339 | ||
340 | IP6T_ENTRY_ITERATE(root, | |
341 | private->size - private->hook_entry[hook], | |
342 | get_chainname_rulenum, | |
343 | e, hookname, &chainname, &comment, &rulenum); | |
344 | ||
345 | nf_log_packet(AF_INET6, hook, skb, in, out, &trace_loginfo, | |
346 | "TRACE: %s:%s:%s:%u ", | |
347 | tablename, chainname, comment, rulenum); | |
348 | } | |
349 | #endif | |
350 | ||
1da177e4 LT |
351 | /* Returns one of the generic firewall policies, like NF_ACCEPT. */ |
352 | unsigned int | |
3db05fea | 353 | ip6t_do_table(struct sk_buff *skb, |
1da177e4 LT |
354 | unsigned int hook, |
355 | const struct net_device *in, | |
356 | const struct net_device *out, | |
fe1cb108 | 357 | struct xt_table *table) |
1da177e4 | 358 | { |
6b7d31fc | 359 | static const char nulldevname[IFNAMSIZ] __attribute__((aligned(sizeof(long)))); |
1da177e4 LT |
360 | int offset = 0; |
361 | unsigned int protoff = 0; | |
cff533ac | 362 | bool hotdrop = false; |
1da177e4 LT |
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; | |
2e4e6a17 | 368 | struct xt_table_info *private; |
1da177e4 LT |
369 | |
370 | /* Initialization */ | |
371 | indev = in ? in->name : nulldevname; | |
372 | outdev = out ? out->name : nulldevname; | |
1da177e4 LT |
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); | |
2e4e6a17 | 381 | private = table->private; |
1da177e4 | 382 | IP_NF_ASSERT(table->valid_hooks & (1 << hook)); |
2e4e6a17 HW |
383 | table_base = (void *)private->entries[smp_processor_id()]; |
384 | e = get_entry(table_base, private->hook_entry[hook]); | |
1da177e4 | 385 | |
1da177e4 | 386 | /* For return from builtin chain */ |
2e4e6a17 | 387 | back = get_entry(table_base, private->underflow[hook]); |
1da177e4 LT |
388 | |
389 | do { | |
390 | IP_NF_ASSERT(e); | |
391 | IP_NF_ASSERT(back); | |
3db05fea | 392 | if (ip6_packet_match(skb, indev, outdev, &e->ipv6, |
51d8b1a6 | 393 | &protoff, &offset, &hotdrop)) { |
1da177e4 LT |
394 | struct ip6t_entry_target *t; |
395 | ||
396 | if (IP6T_MATCH_ITERATE(e, do_match, | |
3db05fea | 397 | skb, in, out, |
1da177e4 LT |
398 | offset, protoff, &hotdrop) != 0) |
399 | goto no_match; | |
400 | ||
401 | ADD_COUNTER(e->counters, | |
3db05fea | 402 | ntohs(ipv6_hdr(skb)->payload_len) |
1da177e4 LT |
403 | + IPV6_HDR_LEN, |
404 | 1); | |
405 | ||
406 | t = ip6t_get_target(e); | |
407 | IP_NF_ASSERT(t->u.kernel.target); | |
ba9dda3a JK |
408 | |
409 | #if defined(CONFIG_NETFILTER_XT_TARGET_TRACE) || \ | |
410 | defined(CONFIG_NETFILTER_XT_TARGET_TRACE_MODULE) | |
411 | /* The packet is traced: log it */ | |
3db05fea HX |
412 | if (unlikely(skb->nf_trace)) |
413 | trace_packet(skb, hook, in, out, | |
ba9dda3a JK |
414 | table->name, private, e); |
415 | #endif | |
1da177e4 LT |
416 | /* Standard target? */ |
417 | if (!t->u.kernel.target->target) { | |
418 | int v; | |
419 | ||
420 | v = ((struct ip6t_standard_target *)t)->verdict; | |
421 | if (v < 0) { | |
422 | /* Pop from stack? */ | |
423 | if (v != IP6T_RETURN) { | |
424 | verdict = (unsigned)(-v) - 1; | |
425 | break; | |
426 | } | |
427 | e = back; | |
428 | back = get_entry(table_base, | |
429 | back->comefrom); | |
430 | continue; | |
431 | } | |
05465343 PM |
432 | if (table_base + v != (void *)e + e->next_offset |
433 | && !(e->ipv6.flags & IP6T_F_GOTO)) { | |
1da177e4 LT |
434 | /* Save old back ptr in next entry */ |
435 | struct ip6t_entry *next | |
436 | = (void *)e + e->next_offset; | |
437 | next->comefrom | |
438 | = (void *)back - table_base; | |
439 | /* set back pointer to next entry */ | |
440 | back = next; | |
441 | } | |
442 | ||
443 | e = get_entry(table_base, v); | |
444 | } else { | |
445 | /* Targets which reenter must return | |
1ab1457c | 446 | abs. verdicts */ |
1da177e4 LT |
447 | #ifdef CONFIG_NETFILTER_DEBUG |
448 | ((struct ip6t_entry *)table_base)->comefrom | |
449 | = 0xeeeeeeec; | |
450 | #endif | |
3db05fea | 451 | verdict = t->u.kernel.target->target(skb, |
1da177e4 LT |
452 | in, out, |
453 | hook, | |
1c524830 | 454 | t->u.kernel.target, |
fe1cb108 | 455 | t->data); |
1da177e4 LT |
456 | |
457 | #ifdef CONFIG_NETFILTER_DEBUG | |
458 | if (((struct ip6t_entry *)table_base)->comefrom | |
459 | != 0xeeeeeeec | |
460 | && verdict == IP6T_CONTINUE) { | |
461 | printk("Target %s reentered!\n", | |
462 | t->u.kernel.target->name); | |
463 | verdict = NF_DROP; | |
464 | } | |
465 | ((struct ip6t_entry *)table_base)->comefrom | |
466 | = 0x57acc001; | |
467 | #endif | |
468 | if (verdict == IP6T_CONTINUE) | |
469 | e = (void *)e + e->next_offset; | |
470 | else | |
471 | /* Verdict */ | |
472 | break; | |
473 | } | |
474 | } else { | |
475 | ||
476 | no_match: | |
477 | e = (void *)e + e->next_offset; | |
478 | } | |
479 | } while (!hotdrop); | |
480 | ||
481 | #ifdef CONFIG_NETFILTER_DEBUG | |
4bdbf6c0 | 482 | ((struct ip6t_entry *)table_base)->comefrom = NETFILTER_LINK_POISON; |
1da177e4 LT |
483 | #endif |
484 | read_unlock_bh(&table->lock); | |
485 | ||
486 | #ifdef DEBUG_ALLOW_ALL | |
487 | return NF_ACCEPT; | |
488 | #else | |
489 | if (hotdrop) | |
490 | return NF_DROP; | |
491 | else return verdict; | |
492 | #endif | |
493 | } | |
494 | ||
1da177e4 LT |
495 | /* Figures out from what hook each rule can be called: returns 0 if |
496 | there are loops. Puts hook bitmask in comefrom. */ | |
497 | static int | |
2e4e6a17 | 498 | mark_source_chains(struct xt_table_info *newinfo, |
31836064 | 499 | unsigned int valid_hooks, void *entry0) |
1da177e4 LT |
500 | { |
501 | unsigned int hook; | |
502 | ||
503 | /* No recursion; use packet counter to save back ptrs (reset | |
504 | to 0 as we leave), and comefrom to save source hook bitmask */ | |
505 | for (hook = 0; hook < NF_IP6_NUMHOOKS; hook++) { | |
506 | unsigned int pos = newinfo->hook_entry[hook]; | |
507 | struct ip6t_entry *e | |
31836064 | 508 | = (struct ip6t_entry *)(entry0 + pos); |
e1b4b9f3 | 509 | int visited = e->comefrom & (1 << hook); |
1da177e4 LT |
510 | |
511 | if (!(valid_hooks & (1 << hook))) | |
512 | continue; | |
513 | ||
514 | /* Set initial back pointer. */ | |
515 | e->counters.pcnt = pos; | |
516 | ||
517 | for (;;) { | |
518 | struct ip6t_standard_target *t | |
519 | = (void *)ip6t_get_target(e); | |
520 | ||
521 | if (e->comefrom & (1 << NF_IP6_NUMHOOKS)) { | |
522 | printk("iptables: loop hook %u pos %u %08X.\n", | |
523 | hook, pos, e->comefrom); | |
524 | return 0; | |
525 | } | |
526 | e->comefrom | |
527 | |= ((1 << hook) | (1 << NF_IP6_NUMHOOKS)); | |
528 | ||
529 | /* Unconditional return/END. */ | |
e1b4b9f3 | 530 | if ((e->target_offset == sizeof(struct ip6t_entry) |
1da177e4 LT |
531 | && (strcmp(t->target.u.user.name, |
532 | IP6T_STANDARD_TARGET) == 0) | |
533 | && t->verdict < 0 | |
e1b4b9f3 | 534 | && unconditional(&e->ipv6)) || visited) { |
1da177e4 LT |
535 | unsigned int oldpos, size; |
536 | ||
74c9c0c1 DM |
537 | if (t->verdict < -NF_MAX_VERDICT - 1) { |
538 | duprintf("mark_source_chains: bad " | |
539 | "negative verdict (%i)\n", | |
540 | t->verdict); | |
541 | return 0; | |
542 | } | |
543 | ||
1da177e4 LT |
544 | /* Return: backtrack through the last |
545 | big jump. */ | |
546 | do { | |
547 | e->comefrom ^= (1<<NF_IP6_NUMHOOKS); | |
548 | #ifdef DEBUG_IP_FIREWALL_USER | |
549 | if (e->comefrom | |
550 | & (1 << NF_IP6_NUMHOOKS)) { | |
551 | duprintf("Back unset " | |
552 | "on hook %u " | |
553 | "rule %u\n", | |
554 | hook, pos); | |
555 | } | |
556 | #endif | |
557 | oldpos = pos; | |
558 | pos = e->counters.pcnt; | |
559 | e->counters.pcnt = 0; | |
560 | ||
561 | /* We're at the start. */ | |
562 | if (pos == oldpos) | |
563 | goto next; | |
564 | ||
565 | e = (struct ip6t_entry *) | |
31836064 | 566 | (entry0 + pos); |
1da177e4 LT |
567 | } while (oldpos == pos + e->next_offset); |
568 | ||
569 | /* Move along one */ | |
570 | size = e->next_offset; | |
571 | e = (struct ip6t_entry *) | |
31836064 | 572 | (entry0 + pos + size); |
1da177e4 LT |
573 | e->counters.pcnt = pos; |
574 | pos += size; | |
575 | } else { | |
576 | int newpos = t->verdict; | |
577 | ||
578 | if (strcmp(t->target.u.user.name, | |
579 | IP6T_STANDARD_TARGET) == 0 | |
580 | && newpos >= 0) { | |
74c9c0c1 DM |
581 | if (newpos > newinfo->size - |
582 | sizeof(struct ip6t_entry)) { | |
583 | duprintf("mark_source_chains: " | |
584 | "bad verdict (%i)\n", | |
585 | newpos); | |
586 | return 0; | |
587 | } | |
1da177e4 LT |
588 | /* This a jump; chase it. */ |
589 | duprintf("Jump rule %u -> %u\n", | |
590 | pos, newpos); | |
591 | } else { | |
592 | /* ... this is a fallthru */ | |
593 | newpos = pos + e->next_offset; | |
594 | } | |
595 | e = (struct ip6t_entry *) | |
31836064 | 596 | (entry0 + newpos); |
1da177e4 LT |
597 | e->counters.pcnt = pos; |
598 | pos = newpos; | |
599 | } | |
600 | } | |
601 | next: | |
602 | duprintf("Finished chain %u\n", hook); | |
603 | } | |
604 | return 1; | |
605 | } | |
606 | ||
607 | static inline int | |
608 | cleanup_match(struct ip6t_entry_match *m, unsigned int *i) | |
609 | { | |
610 | if (i && (*i)-- == 0) | |
611 | return 1; | |
612 | ||
613 | if (m->u.kernel.match->destroy) | |
efa74165 | 614 | m->u.kernel.match->destroy(m->u.kernel.match, m->data); |
1da177e4 LT |
615 | module_put(m->u.kernel.match->me); |
616 | return 0; | |
617 | } | |
618 | ||
1da177e4 LT |
619 | static inline int |
620 | check_match(struct ip6t_entry_match *m, | |
621 | const char *name, | |
622 | const struct ip6t_ip6 *ipv6, | |
623 | unsigned int hookmask, | |
624 | unsigned int *i) | |
625 | { | |
6709dbbb | 626 | struct xt_match *match; |
3cdc7c95 | 627 | int ret; |
1da177e4 | 628 | |
2e4e6a17 | 629 | match = try_then_request_module(xt_find_match(AF_INET6, m->u.user.name, |
1ab1457c | 630 | m->u.user.revision), |
6b7d31fc HW |
631 | "ip6t_%s", m->u.user.name); |
632 | if (IS_ERR(match) || !match) { | |
1ab1457c | 633 | duprintf("check_match: `%s' not found\n", m->u.user.name); |
6b7d31fc | 634 | return match ? PTR_ERR(match) : -ENOENT; |
1da177e4 LT |
635 | } |
636 | m->u.kernel.match = match; | |
1da177e4 | 637 | |
3cdc7c95 PM |
638 | ret = xt_check_match(match, AF_INET6, m->u.match_size - sizeof(*m), |
639 | name, hookmask, ipv6->proto, | |
640 | ipv6->invflags & IP6T_INV_PROTO); | |
641 | if (ret) | |
642 | goto err; | |
643 | ||
1da177e4 | 644 | if (m->u.kernel.match->checkentry |
1c524830 | 645 | && !m->u.kernel.match->checkentry(name, ipv6, match, m->data, |
1da177e4 | 646 | hookmask)) { |
1da177e4 LT |
647 | duprintf("ip_tables: check failed for `%s'.\n", |
648 | m->u.kernel.match->name); | |
3cdc7c95 PM |
649 | ret = -EINVAL; |
650 | goto err; | |
1da177e4 LT |
651 | } |
652 | ||
653 | (*i)++; | |
654 | return 0; | |
3cdc7c95 PM |
655 | err: |
656 | module_put(m->u.kernel.match->me); | |
657 | return ret; | |
1da177e4 LT |
658 | } |
659 | ||
6709dbbb | 660 | static struct xt_target ip6t_standard_target; |
1da177e4 LT |
661 | |
662 | static inline int | |
663 | check_entry(struct ip6t_entry *e, const char *name, unsigned int size, | |
664 | unsigned int *i) | |
665 | { | |
666 | struct ip6t_entry_target *t; | |
6709dbbb | 667 | struct xt_target *target; |
1da177e4 LT |
668 | int ret; |
669 | unsigned int j; | |
670 | ||
671 | if (!ip6_checkentry(&e->ipv6)) { | |
672 | duprintf("ip_tables: ip check failed %p %s.\n", e, name); | |
673 | return -EINVAL; | |
674 | } | |
675 | ||
590bdf7f DM |
676 | if (e->target_offset + sizeof(struct ip6t_entry_target) > |
677 | e->next_offset) | |
678 | return -EINVAL; | |
679 | ||
1da177e4 LT |
680 | j = 0; |
681 | ret = IP6T_MATCH_ITERATE(e, check_match, name, &e->ipv6, e->comefrom, &j); | |
682 | if (ret != 0) | |
683 | goto cleanup_matches; | |
684 | ||
685 | t = ip6t_get_target(e); | |
590bdf7f DM |
686 | ret = -EINVAL; |
687 | if (e->target_offset + t->u.target_size > e->next_offset) | |
688 | goto cleanup_matches; | |
2e4e6a17 HW |
689 | target = try_then_request_module(xt_find_target(AF_INET6, |
690 | t->u.user.name, | |
691 | t->u.user.revision), | |
6b7d31fc HW |
692 | "ip6t_%s", t->u.user.name); |
693 | if (IS_ERR(target) || !target) { | |
1da177e4 | 694 | duprintf("check_entry: `%s' not found\n", t->u.user.name); |
6b7d31fc | 695 | ret = target ? PTR_ERR(target) : -ENOENT; |
1da177e4 LT |
696 | goto cleanup_matches; |
697 | } | |
698 | t->u.kernel.target = target; | |
6b7d31fc | 699 | |
3cdc7c95 PM |
700 | ret = xt_check_target(target, AF_INET6, t->u.target_size - sizeof(*t), |
701 | name, e->comefrom, e->ipv6.proto, | |
702 | e->ipv6.invflags & IP6T_INV_PROTO); | |
703 | if (ret) | |
704 | goto err; | |
705 | ||
74c9c0c1 | 706 | if (t->u.kernel.target->checkentry |
1c524830 | 707 | && !t->u.kernel.target->checkentry(name, e, target, t->data, |
1da177e4 | 708 | e->comefrom)) { |
1da177e4 LT |
709 | duprintf("ip_tables: check failed for `%s'.\n", |
710 | t->u.kernel.target->name); | |
711 | ret = -EINVAL; | |
3cdc7c95 | 712 | goto err; |
1da177e4 LT |
713 | } |
714 | ||
715 | (*i)++; | |
716 | return 0; | |
3cdc7c95 PM |
717 | err: |
718 | module_put(t->u.kernel.target->me); | |
1da177e4 LT |
719 | cleanup_matches: |
720 | IP6T_MATCH_ITERATE(e, cleanup_match, &j); | |
721 | return ret; | |
722 | } | |
723 | ||
724 | static inline int | |
725 | check_entry_size_and_hooks(struct ip6t_entry *e, | |
2e4e6a17 | 726 | struct xt_table_info *newinfo, |
1da177e4 LT |
727 | unsigned char *base, |
728 | unsigned char *limit, | |
729 | const unsigned int *hook_entries, | |
730 | const unsigned int *underflows, | |
731 | unsigned int *i) | |
732 | { | |
733 | unsigned int h; | |
734 | ||
735 | if ((unsigned long)e % __alignof__(struct ip6t_entry) != 0 | |
736 | || (unsigned char *)e + sizeof(struct ip6t_entry) >= limit) { | |
737 | duprintf("Bad offset %p\n", e); | |
738 | return -EINVAL; | |
739 | } | |
740 | ||
741 | if (e->next_offset | |
742 | < sizeof(struct ip6t_entry) + sizeof(struct ip6t_entry_target)) { | |
743 | duprintf("checking: element %p size %u\n", | |
744 | e, e->next_offset); | |
745 | return -EINVAL; | |
746 | } | |
747 | ||
748 | /* Check hooks & underflows */ | |
749 | for (h = 0; h < NF_IP6_NUMHOOKS; h++) { | |
750 | if ((unsigned char *)e - base == hook_entries[h]) | |
751 | newinfo->hook_entry[h] = hook_entries[h]; | |
752 | if ((unsigned char *)e - base == underflows[h]) | |
753 | newinfo->underflow[h] = underflows[h]; | |
754 | } | |
755 | ||
756 | /* FIXME: underflows must be unconditional, standard verdicts | |
1ab1457c | 757 | < 0 (not IP6T_RETURN). --RR */ |
1da177e4 LT |
758 | |
759 | /* Clear counters and comefrom */ | |
2e4e6a17 | 760 | e->counters = ((struct xt_counters) { 0, 0 }); |
1da177e4 LT |
761 | e->comefrom = 0; |
762 | ||
763 | (*i)++; | |
764 | return 0; | |
765 | } | |
766 | ||
767 | static inline int | |
768 | cleanup_entry(struct ip6t_entry *e, unsigned int *i) | |
769 | { | |
770 | struct ip6t_entry_target *t; | |
771 | ||
772 | if (i && (*i)-- == 0) | |
773 | return 1; | |
774 | ||
775 | /* Cleanup all matches */ | |
776 | IP6T_MATCH_ITERATE(e, cleanup_match, NULL); | |
777 | t = ip6t_get_target(e); | |
778 | if (t->u.kernel.target->destroy) | |
efa74165 | 779 | t->u.kernel.target->destroy(t->u.kernel.target, t->data); |
1da177e4 LT |
780 | module_put(t->u.kernel.target->me); |
781 | return 0; | |
782 | } | |
783 | ||
784 | /* Checks and translates the user-supplied table segment (held in | |
785 | newinfo) */ | |
786 | static int | |
787 | translate_table(const char *name, | |
788 | unsigned int valid_hooks, | |
2e4e6a17 | 789 | struct xt_table_info *newinfo, |
31836064 | 790 | void *entry0, |
1da177e4 LT |
791 | unsigned int size, |
792 | unsigned int number, | |
793 | const unsigned int *hook_entries, | |
794 | const unsigned int *underflows) | |
795 | { | |
796 | unsigned int i; | |
797 | int ret; | |
798 | ||
799 | newinfo->size = size; | |
800 | newinfo->number = number; | |
801 | ||
802 | /* Init all hooks to impossible value. */ | |
803 | for (i = 0; i < NF_IP6_NUMHOOKS; i++) { | |
804 | newinfo->hook_entry[i] = 0xFFFFFFFF; | |
805 | newinfo->underflow[i] = 0xFFFFFFFF; | |
806 | } | |
807 | ||
808 | duprintf("translate_table: size %u\n", newinfo->size); | |
809 | i = 0; | |
810 | /* Walk through entries, checking offsets. */ | |
31836064 | 811 | ret = IP6T_ENTRY_ITERATE(entry0, newinfo->size, |
1da177e4 LT |
812 | check_entry_size_and_hooks, |
813 | newinfo, | |
31836064 ED |
814 | entry0, |
815 | entry0 + size, | |
1da177e4 LT |
816 | hook_entries, underflows, &i); |
817 | if (ret != 0) | |
818 | return ret; | |
819 | ||
820 | if (i != number) { | |
821 | duprintf("translate_table: %u not %u entries\n", | |
822 | i, number); | |
823 | return -EINVAL; | |
824 | } | |
825 | ||
826 | /* Check hooks all assigned */ | |
827 | for (i = 0; i < NF_IP6_NUMHOOKS; i++) { | |
828 | /* Only hooks which are valid */ | |
829 | if (!(valid_hooks & (1 << i))) | |
830 | continue; | |
831 | if (newinfo->hook_entry[i] == 0xFFFFFFFF) { | |
832 | duprintf("Invalid hook entry %u %u\n", | |
833 | i, hook_entries[i]); | |
834 | return -EINVAL; | |
835 | } | |
836 | if (newinfo->underflow[i] == 0xFFFFFFFF) { | |
837 | duprintf("Invalid underflow %u %u\n", | |
838 | i, underflows[i]); | |
839 | return -EINVAL; | |
840 | } | |
841 | } | |
842 | ||
74c9c0c1 DM |
843 | if (!mark_source_chains(newinfo, valid_hooks, entry0)) |
844 | return -ELOOP; | |
845 | ||
1da177e4 LT |
846 | /* Finally, each sanity check must pass */ |
847 | i = 0; | |
31836064 | 848 | ret = IP6T_ENTRY_ITERATE(entry0, newinfo->size, |
1da177e4 LT |
849 | check_entry, name, size, &i); |
850 | ||
74c9c0c1 DM |
851 | if (ret != 0) { |
852 | IP6T_ENTRY_ITERATE(entry0, newinfo->size, | |
853 | cleanup_entry, &i); | |
854 | return ret; | |
855 | } | |
1da177e4 LT |
856 | |
857 | /* And one copy for every other CPU */ | |
6f912042 | 858 | for_each_possible_cpu(i) { |
31836064 ED |
859 | if (newinfo->entries[i] && newinfo->entries[i] != entry0) |
860 | memcpy(newinfo->entries[i], entry0, newinfo->size); | |
1da177e4 LT |
861 | } |
862 | ||
590bdf7f | 863 | return 0; |
1da177e4 LT |
864 | } |
865 | ||
1da177e4 LT |
866 | /* Gets counters. */ |
867 | static inline int | |
868 | add_entry_to_counter(const struct ip6t_entry *e, | |
2e4e6a17 | 869 | struct xt_counters total[], |
1da177e4 LT |
870 | unsigned int *i) |
871 | { | |
872 | ADD_COUNTER(total[*i], e->counters.bcnt, e->counters.pcnt); | |
873 | ||
874 | (*i)++; | |
875 | return 0; | |
876 | } | |
877 | ||
31836064 ED |
878 | static inline int |
879 | set_entry_to_counter(const struct ip6t_entry *e, | |
880 | struct ip6t_counters total[], | |
881 | unsigned int *i) | |
882 | { | |
883 | SET_COUNTER(total[*i], e->counters.bcnt, e->counters.pcnt); | |
884 | ||
885 | (*i)++; | |
886 | return 0; | |
887 | } | |
888 | ||
1da177e4 | 889 | static void |
2e4e6a17 HW |
890 | get_counters(const struct xt_table_info *t, |
891 | struct xt_counters counters[]) | |
1da177e4 LT |
892 | { |
893 | unsigned int cpu; | |
894 | unsigned int i; | |
31836064 ED |
895 | unsigned int curcpu; |
896 | ||
897 | /* Instead of clearing (by a previous call to memset()) | |
898 | * the counters and using adds, we set the counters | |
899 | * with data used by 'current' CPU | |
900 | * We dont care about preemption here. | |
901 | */ | |
902 | curcpu = raw_smp_processor_id(); | |
903 | ||
904 | i = 0; | |
905 | IP6T_ENTRY_ITERATE(t->entries[curcpu], | |
906 | t->size, | |
907 | set_entry_to_counter, | |
908 | counters, | |
909 | &i); | |
1da177e4 | 910 | |
6f912042 | 911 | for_each_possible_cpu(cpu) { |
31836064 ED |
912 | if (cpu == curcpu) |
913 | continue; | |
1da177e4 | 914 | i = 0; |
31836064 | 915 | IP6T_ENTRY_ITERATE(t->entries[cpu], |
1da177e4 LT |
916 | t->size, |
917 | add_entry_to_counter, | |
918 | counters, | |
919 | &i); | |
920 | } | |
921 | } | |
922 | ||
923 | static int | |
924 | copy_entries_to_user(unsigned int total_size, | |
2e4e6a17 | 925 | struct xt_table *table, |
1da177e4 LT |
926 | void __user *userptr) |
927 | { | |
928 | unsigned int off, num, countersize; | |
929 | struct ip6t_entry *e; | |
2e4e6a17 HW |
930 | struct xt_counters *counters; |
931 | struct xt_table_info *private = table->private; | |
1da177e4 | 932 | int ret = 0; |
31836064 | 933 | void *loc_cpu_entry; |
1da177e4 LT |
934 | |
935 | /* We need atomic snapshot of counters: rest doesn't change | |
936 | (other than comefrom, which userspace doesn't care | |
937 | about). */ | |
2e4e6a17 | 938 | countersize = sizeof(struct xt_counters) * private->number; |
1da177e4 LT |
939 | counters = vmalloc(countersize); |
940 | ||
941 | if (counters == NULL) | |
942 | return -ENOMEM; | |
943 | ||
944 | /* First, sum counters... */ | |
1da177e4 | 945 | write_lock_bh(&table->lock); |
2e4e6a17 | 946 | get_counters(private, counters); |
1da177e4 LT |
947 | write_unlock_bh(&table->lock); |
948 | ||
31836064 | 949 | /* choose the copy that is on ourc node/cpu */ |
2e4e6a17 | 950 | loc_cpu_entry = private->entries[raw_smp_processor_id()]; |
31836064 | 951 | if (copy_to_user(userptr, loc_cpu_entry, total_size) != 0) { |
1da177e4 LT |
952 | ret = -EFAULT; |
953 | goto free_counters; | |
954 | } | |
955 | ||
956 | /* FIXME: use iterator macros --RR */ | |
957 | /* ... then go back and fix counters and names */ | |
958 | for (off = 0, num = 0; off < total_size; off += e->next_offset, num++){ | |
959 | unsigned int i; | |
960 | struct ip6t_entry_match *m; | |
961 | struct ip6t_entry_target *t; | |
962 | ||
31836064 | 963 | e = (struct ip6t_entry *)(loc_cpu_entry + off); |
1da177e4 LT |
964 | if (copy_to_user(userptr + off |
965 | + offsetof(struct ip6t_entry, counters), | |
966 | &counters[num], | |
967 | sizeof(counters[num])) != 0) { | |
968 | ret = -EFAULT; | |
969 | goto free_counters; | |
970 | } | |
971 | ||
972 | for (i = sizeof(struct ip6t_entry); | |
973 | i < e->target_offset; | |
974 | i += m->u.match_size) { | |
975 | m = (void *)e + i; | |
976 | ||
977 | if (copy_to_user(userptr + off + i | |
978 | + offsetof(struct ip6t_entry_match, | |
979 | u.user.name), | |
980 | m->u.kernel.match->name, | |
981 | strlen(m->u.kernel.match->name)+1) | |
982 | != 0) { | |
983 | ret = -EFAULT; | |
984 | goto free_counters; | |
985 | } | |
986 | } | |
987 | ||
988 | t = ip6t_get_target(e); | |
989 | if (copy_to_user(userptr + off + e->target_offset | |
990 | + offsetof(struct ip6t_entry_target, | |
991 | u.user.name), | |
992 | t->u.kernel.target->name, | |
993 | strlen(t->u.kernel.target->name)+1) != 0) { | |
994 | ret = -EFAULT; | |
995 | goto free_counters; | |
996 | } | |
997 | } | |
998 | ||
999 | free_counters: | |
1000 | vfree(counters); | |
1001 | return ret; | |
1002 | } | |
1003 | ||
1004 | static int | |
1005 | get_entries(const struct ip6t_get_entries *entries, | |
1006 | struct ip6t_get_entries __user *uptr) | |
1007 | { | |
1008 | int ret; | |
2e4e6a17 | 1009 | struct xt_table *t; |
1da177e4 | 1010 | |
2e4e6a17 | 1011 | t = xt_find_table_lock(AF_INET6, entries->name); |
6b7d31fc | 1012 | if (t && !IS_ERR(t)) { |
2e4e6a17 HW |
1013 | struct xt_table_info *private = t->private; |
1014 | duprintf("t->private->number = %u\n", private->number); | |
1015 | if (entries->size == private->size) | |
1016 | ret = copy_entries_to_user(private->size, | |
1da177e4 LT |
1017 | t, uptr->entrytable); |
1018 | else { | |
1019 | duprintf("get_entries: I've got %u not %u!\n", | |
2e4e6a17 | 1020 | private->size, entries->size); |
1da177e4 LT |
1021 | ret = -EINVAL; |
1022 | } | |
6b7d31fc | 1023 | module_put(t->me); |
2e4e6a17 | 1024 | xt_table_unlock(t); |
1da177e4 | 1025 | } else |
6b7d31fc | 1026 | ret = t ? PTR_ERR(t) : -ENOENT; |
1da177e4 LT |
1027 | |
1028 | return ret; | |
1029 | } | |
1030 | ||
1031 | static int | |
1032 | do_replace(void __user *user, unsigned int len) | |
1033 | { | |
1034 | int ret; | |
1035 | struct ip6t_replace tmp; | |
2e4e6a17 HW |
1036 | struct xt_table *t; |
1037 | struct xt_table_info *newinfo, *oldinfo; | |
1038 | struct xt_counters *counters; | |
31836064 | 1039 | void *loc_cpu_entry, *loc_cpu_old_entry; |
1da177e4 LT |
1040 | |
1041 | if (copy_from_user(&tmp, user, sizeof(tmp)) != 0) | |
1042 | return -EFAULT; | |
1043 | ||
ee4bb818 KK |
1044 | /* overflow check */ |
1045 | if (tmp.size >= (INT_MAX - sizeof(struct xt_table_info)) / NR_CPUS - | |
1046 | SMP_CACHE_BYTES) | |
1047 | return -ENOMEM; | |
1048 | if (tmp.num_counters >= INT_MAX / sizeof(struct xt_counters)) | |
1049 | return -ENOMEM; | |
1050 | ||
2e4e6a17 | 1051 | newinfo = xt_alloc_table_info(tmp.size); |
1da177e4 LT |
1052 | if (!newinfo) |
1053 | return -ENOMEM; | |
1054 | ||
31836064 ED |
1055 | /* choose the copy that is on our node/cpu */ |
1056 | loc_cpu_entry = newinfo->entries[raw_smp_processor_id()]; | |
1057 | if (copy_from_user(loc_cpu_entry, user + sizeof(tmp), | |
1da177e4 LT |
1058 | tmp.size) != 0) { |
1059 | ret = -EFAULT; | |
1060 | goto free_newinfo; | |
1061 | } | |
1062 | ||
2e4e6a17 | 1063 | counters = vmalloc(tmp.num_counters * sizeof(struct xt_counters)); |
1da177e4 LT |
1064 | if (!counters) { |
1065 | ret = -ENOMEM; | |
1066 | goto free_newinfo; | |
1067 | } | |
1da177e4 LT |
1068 | |
1069 | ret = translate_table(tmp.name, tmp.valid_hooks, | |
31836064 | 1070 | newinfo, loc_cpu_entry, tmp.size, tmp.num_entries, |
1da177e4 LT |
1071 | tmp.hook_entry, tmp.underflow); |
1072 | if (ret != 0) | |
1073 | goto free_newinfo_counters; | |
1074 | ||
1075 | duprintf("ip_tables: Translated table\n"); | |
1076 | ||
2e4e6a17 | 1077 | t = try_then_request_module(xt_find_table_lock(AF_INET6, tmp.name), |
6b7d31fc HW |
1078 | "ip6table_%s", tmp.name); |
1079 | if (!t || IS_ERR(t)) { | |
1080 | ret = t ? PTR_ERR(t) : -ENOENT; | |
1da177e4 | 1081 | goto free_newinfo_counters_untrans; |
6b7d31fc | 1082 | } |
1da177e4 LT |
1083 | |
1084 | /* You lied! */ | |
1085 | if (tmp.valid_hooks != t->valid_hooks) { | |
1086 | duprintf("Valid hook crap: %08X vs %08X\n", | |
1087 | tmp.valid_hooks, t->valid_hooks); | |
1088 | ret = -EINVAL; | |
6b7d31fc | 1089 | goto put_module; |
1da177e4 LT |
1090 | } |
1091 | ||
2e4e6a17 | 1092 | oldinfo = xt_replace_table(t, tmp.num_counters, newinfo, &ret); |
1da177e4 LT |
1093 | if (!oldinfo) |
1094 | goto put_module; | |
1095 | ||
1096 | /* Update module usage count based on number of rules */ | |
1097 | duprintf("do_replace: oldnum=%u, initnum=%u, newnum=%u\n", | |
1098 | oldinfo->number, oldinfo->initial_entries, newinfo->number); | |
1ab1457c YH |
1099 | if ((oldinfo->number > oldinfo->initial_entries) || |
1100 | (newinfo->number <= oldinfo->initial_entries)) | |
1da177e4 LT |
1101 | module_put(t->me); |
1102 | if ((oldinfo->number > oldinfo->initial_entries) && | |
1103 | (newinfo->number <= oldinfo->initial_entries)) | |
1104 | module_put(t->me); | |
1105 | ||
1106 | /* Get the old counters. */ | |
1107 | get_counters(oldinfo, counters); | |
1108 | /* Decrease module usage counts and free resource */ | |
31836064 ED |
1109 | loc_cpu_old_entry = oldinfo->entries[raw_smp_processor_id()]; |
1110 | IP6T_ENTRY_ITERATE(loc_cpu_old_entry, oldinfo->size, cleanup_entry,NULL); | |
2e4e6a17 | 1111 | xt_free_table_info(oldinfo); |
1da177e4 | 1112 | if (copy_to_user(tmp.counters, counters, |
2e4e6a17 | 1113 | sizeof(struct xt_counters) * tmp.num_counters) != 0) |
1da177e4 LT |
1114 | ret = -EFAULT; |
1115 | vfree(counters); | |
2e4e6a17 | 1116 | xt_table_unlock(t); |
1da177e4 LT |
1117 | return ret; |
1118 | ||
1119 | put_module: | |
1120 | module_put(t->me); | |
2e4e6a17 | 1121 | xt_table_unlock(t); |
1da177e4 | 1122 | free_newinfo_counters_untrans: |
31836064 | 1123 | IP6T_ENTRY_ITERATE(loc_cpu_entry, newinfo->size, cleanup_entry,NULL); |
1da177e4 LT |
1124 | free_newinfo_counters: |
1125 | vfree(counters); | |
1126 | free_newinfo: | |
2e4e6a17 | 1127 | xt_free_table_info(newinfo); |
1da177e4 LT |
1128 | return ret; |
1129 | } | |
1130 | ||
1131 | /* We're lazy, and add to the first CPU; overflow works its fey magic | |
1132 | * and everything is OK. */ | |
1133 | static inline int | |
1134 | add_counter_to_entry(struct ip6t_entry *e, | |
2e4e6a17 | 1135 | const struct xt_counters addme[], |
1da177e4 LT |
1136 | unsigned int *i) |
1137 | { | |
1138 | #if 0 | |
1139 | duprintf("add_counter: Entry %u %lu/%lu + %lu/%lu\n", | |
1140 | *i, | |
1141 | (long unsigned int)e->counters.pcnt, | |
1142 | (long unsigned int)e->counters.bcnt, | |
1143 | (long unsigned int)addme[*i].pcnt, | |
1144 | (long unsigned int)addme[*i].bcnt); | |
1145 | #endif | |
1146 | ||
1147 | ADD_COUNTER(e->counters, addme[*i].bcnt, addme[*i].pcnt); | |
1148 | ||
1149 | (*i)++; | |
1150 | return 0; | |
1151 | } | |
1152 | ||
1153 | static int | |
1154 | do_add_counters(void __user *user, unsigned int len) | |
1155 | { | |
1156 | unsigned int i; | |
2e4e6a17 HW |
1157 | struct xt_counters_info tmp, *paddc; |
1158 | struct xt_table_info *private; | |
1159 | struct xt_table *t; | |
6b7d31fc | 1160 | int ret = 0; |
31836064 | 1161 | void *loc_cpu_entry; |
1da177e4 LT |
1162 | |
1163 | if (copy_from_user(&tmp, user, sizeof(tmp)) != 0) | |
1164 | return -EFAULT; | |
1165 | ||
2e4e6a17 | 1166 | if (len != sizeof(tmp) + tmp.num_counters*sizeof(struct xt_counters)) |
1da177e4 LT |
1167 | return -EINVAL; |
1168 | ||
1169 | paddc = vmalloc(len); | |
1170 | if (!paddc) | |
1171 | return -ENOMEM; | |
1172 | ||
1173 | if (copy_from_user(paddc, user, len) != 0) { | |
1174 | ret = -EFAULT; | |
1175 | goto free; | |
1176 | } | |
1177 | ||
2e4e6a17 | 1178 | t = xt_find_table_lock(AF_INET6, tmp.name); |
6b7d31fc HW |
1179 | if (!t || IS_ERR(t)) { |
1180 | ret = t ? PTR_ERR(t) : -ENOENT; | |
1da177e4 | 1181 | goto free; |
6b7d31fc | 1182 | } |
1da177e4 LT |
1183 | |
1184 | write_lock_bh(&t->lock); | |
2e4e6a17 | 1185 | private = t->private; |
2c8ac66b | 1186 | if (private->number != tmp.num_counters) { |
1da177e4 LT |
1187 | ret = -EINVAL; |
1188 | goto unlock_up_free; | |
1189 | } | |
1190 | ||
1191 | i = 0; | |
31836064 | 1192 | /* Choose the copy that is on our node */ |
2e4e6a17 | 1193 | loc_cpu_entry = private->entries[smp_processor_id()]; |
31836064 | 1194 | IP6T_ENTRY_ITERATE(loc_cpu_entry, |
2e4e6a17 | 1195 | private->size, |
1da177e4 LT |
1196 | add_counter_to_entry, |
1197 | paddc->counters, | |
1198 | &i); | |
1199 | unlock_up_free: | |
1200 | write_unlock_bh(&t->lock); | |
2e4e6a17 | 1201 | xt_table_unlock(t); |
6b7d31fc | 1202 | module_put(t->me); |
1da177e4 LT |
1203 | free: |
1204 | vfree(paddc); | |
1205 | ||
1206 | return ret; | |
1207 | } | |
1208 | ||
1209 | static int | |
1210 | do_ip6t_set_ctl(struct sock *sk, int cmd, void __user *user, unsigned int len) | |
1211 | { | |
1212 | int ret; | |
1213 | ||
1214 | if (!capable(CAP_NET_ADMIN)) | |
1215 | return -EPERM; | |
1216 | ||
1217 | switch (cmd) { | |
1218 | case IP6T_SO_SET_REPLACE: | |
1219 | ret = do_replace(user, len); | |
1220 | break; | |
1221 | ||
1222 | case IP6T_SO_SET_ADD_COUNTERS: | |
1223 | ret = do_add_counters(user, len); | |
1224 | break; | |
1225 | ||
1226 | default: | |
1227 | duprintf("do_ip6t_set_ctl: unknown request %i\n", cmd); | |
1228 | ret = -EINVAL; | |
1229 | } | |
1230 | ||
1231 | return ret; | |
1232 | } | |
1233 | ||
1234 | static int | |
1235 | do_ip6t_get_ctl(struct sock *sk, int cmd, void __user *user, int *len) | |
1236 | { | |
1237 | int ret; | |
1238 | ||
1239 | if (!capable(CAP_NET_ADMIN)) | |
1240 | return -EPERM; | |
1241 | ||
1242 | switch (cmd) { | |
1243 | case IP6T_SO_GET_INFO: { | |
1244 | char name[IP6T_TABLE_MAXNAMELEN]; | |
2e4e6a17 | 1245 | struct xt_table *t; |
1da177e4 LT |
1246 | |
1247 | if (*len != sizeof(struct ip6t_getinfo)) { | |
1248 | duprintf("length %u != %u\n", *len, | |
1249 | sizeof(struct ip6t_getinfo)); | |
1250 | ret = -EINVAL; | |
1251 | break; | |
1252 | } | |
1253 | ||
1254 | if (copy_from_user(name, user, sizeof(name)) != 0) { | |
1255 | ret = -EFAULT; | |
1256 | break; | |
1257 | } | |
1258 | name[IP6T_TABLE_MAXNAMELEN-1] = '\0'; | |
6b7d31fc | 1259 | |
2e4e6a17 | 1260 | t = try_then_request_module(xt_find_table_lock(AF_INET6, name), |
6b7d31fc HW |
1261 | "ip6table_%s", name); |
1262 | if (t && !IS_ERR(t)) { | |
1da177e4 | 1263 | struct ip6t_getinfo info; |
2e4e6a17 | 1264 | struct xt_table_info *private = t->private; |
1da177e4 LT |
1265 | |
1266 | info.valid_hooks = t->valid_hooks; | |
2e4e6a17 | 1267 | memcpy(info.hook_entry, private->hook_entry, |
1da177e4 | 1268 | sizeof(info.hook_entry)); |
2e4e6a17 | 1269 | memcpy(info.underflow, private->underflow, |
1da177e4 | 1270 | sizeof(info.underflow)); |
2e4e6a17 HW |
1271 | info.num_entries = private->number; |
1272 | info.size = private->size; | |
1da177e4 LT |
1273 | memcpy(info.name, name, sizeof(info.name)); |
1274 | ||
1275 | if (copy_to_user(user, &info, *len) != 0) | |
1276 | ret = -EFAULT; | |
1277 | else | |
1278 | ret = 0; | |
2e4e6a17 | 1279 | xt_table_unlock(t); |
6b7d31fc HW |
1280 | module_put(t->me); |
1281 | } else | |
1282 | ret = t ? PTR_ERR(t) : -ENOENT; | |
1da177e4 LT |
1283 | } |
1284 | break; | |
1285 | ||
1286 | case IP6T_SO_GET_ENTRIES: { | |
1287 | struct ip6t_get_entries get; | |
1288 | ||
1289 | if (*len < sizeof(get)) { | |
1290 | duprintf("get_entries: %u < %u\n", *len, sizeof(get)); | |
1291 | ret = -EINVAL; | |
1292 | } else if (copy_from_user(&get, user, sizeof(get)) != 0) { | |
1293 | ret = -EFAULT; | |
1294 | } else if (*len != sizeof(struct ip6t_get_entries) + get.size) { | |
1295 | duprintf("get_entries: %u != %u\n", *len, | |
1296 | sizeof(struct ip6t_get_entries) + get.size); | |
1297 | ret = -EINVAL; | |
1298 | } else | |
1299 | ret = get_entries(&get, user); | |
1300 | break; | |
1301 | } | |
1302 | ||
6b7d31fc HW |
1303 | case IP6T_SO_GET_REVISION_MATCH: |
1304 | case IP6T_SO_GET_REVISION_TARGET: { | |
1305 | struct ip6t_get_revision rev; | |
2e4e6a17 | 1306 | int target; |
6b7d31fc HW |
1307 | |
1308 | if (*len != sizeof(rev)) { | |
1309 | ret = -EINVAL; | |
1310 | break; | |
1311 | } | |
1312 | if (copy_from_user(&rev, user, sizeof(rev)) != 0) { | |
1313 | ret = -EFAULT; | |
1314 | break; | |
1315 | } | |
1316 | ||
1317 | if (cmd == IP6T_SO_GET_REVISION_TARGET) | |
2e4e6a17 | 1318 | target = 1; |
6b7d31fc | 1319 | else |
2e4e6a17 | 1320 | target = 0; |
6b7d31fc | 1321 | |
2e4e6a17 HW |
1322 | try_then_request_module(xt_find_revision(AF_INET6, rev.name, |
1323 | rev.revision, | |
1324 | target, &ret), | |
6b7d31fc HW |
1325 | "ip6t_%s", rev.name); |
1326 | break; | |
1327 | } | |
1328 | ||
1da177e4 LT |
1329 | default: |
1330 | duprintf("do_ip6t_get_ctl: unknown request %i\n", cmd); | |
1331 | ret = -EINVAL; | |
1332 | } | |
1333 | ||
1334 | return ret; | |
1335 | } | |
1336 | ||
2e4e6a17 | 1337 | int ip6t_register_table(struct xt_table *table, |
1da177e4 LT |
1338 | const struct ip6t_replace *repl) |
1339 | { | |
1340 | int ret; | |
2e4e6a17 HW |
1341 | struct xt_table_info *newinfo; |
1342 | static struct xt_table_info bootstrap | |
1da177e4 | 1343 | = { 0, 0, 0, { 0 }, { 0 }, { } }; |
31836064 | 1344 | void *loc_cpu_entry; |
1da177e4 | 1345 | |
2e4e6a17 | 1346 | newinfo = xt_alloc_table_info(repl->size); |
1da177e4 LT |
1347 | if (!newinfo) |
1348 | return -ENOMEM; | |
1349 | ||
31836064 ED |
1350 | /* choose the copy on our node/cpu */ |
1351 | loc_cpu_entry = newinfo->entries[raw_smp_processor_id()]; | |
1352 | memcpy(loc_cpu_entry, repl->entries, repl->size); | |
1da177e4 LT |
1353 | |
1354 | ret = translate_table(table->name, table->valid_hooks, | |
31836064 | 1355 | newinfo, loc_cpu_entry, repl->size, |
1da177e4 LT |
1356 | repl->num_entries, |
1357 | repl->hook_entry, | |
1358 | repl->underflow); | |
1359 | if (ret != 0) { | |
2e4e6a17 | 1360 | xt_free_table_info(newinfo); |
1da177e4 LT |
1361 | return ret; |
1362 | } | |
1363 | ||
da298d3a PM |
1364 | ret = xt_register_table(table, &bootstrap, newinfo); |
1365 | if (ret != 0) { | |
2e4e6a17 | 1366 | xt_free_table_info(newinfo); |
1da177e4 LT |
1367 | return ret; |
1368 | } | |
1369 | ||
2e4e6a17 | 1370 | return 0; |
1da177e4 LT |
1371 | } |
1372 | ||
2e4e6a17 | 1373 | void ip6t_unregister_table(struct xt_table *table) |
1da177e4 | 1374 | { |
2e4e6a17 | 1375 | struct xt_table_info *private; |
31836064 ED |
1376 | void *loc_cpu_entry; |
1377 | ||
2e4e6a17 | 1378 | private = xt_unregister_table(table); |
1da177e4 LT |
1379 | |
1380 | /* Decrease module usage counts and free resources */ | |
2e4e6a17 HW |
1381 | loc_cpu_entry = private->entries[raw_smp_processor_id()]; |
1382 | IP6T_ENTRY_ITERATE(loc_cpu_entry, private->size, cleanup_entry, NULL); | |
1383 | xt_free_table_info(private); | |
1da177e4 LT |
1384 | } |
1385 | ||
1386 | /* Returns 1 if the type and code is matched by the range, 0 otherwise */ | |
ccb79bdc | 1387 | static inline bool |
1da177e4 LT |
1388 | icmp6_type_code_match(u_int8_t test_type, u_int8_t min_code, u_int8_t max_code, |
1389 | u_int8_t type, u_int8_t code, | |
ccb79bdc | 1390 | bool invert) |
1da177e4 LT |
1391 | { |
1392 | return (type == test_type && code >= min_code && code <= max_code) | |
1393 | ^ invert; | |
1394 | } | |
1395 | ||
1d93a9cb | 1396 | static bool |
1da177e4 LT |
1397 | icmp6_match(const struct sk_buff *skb, |
1398 | const struct net_device *in, | |
1399 | const struct net_device *out, | |
c4986734 | 1400 | const struct xt_match *match, |
1da177e4 LT |
1401 | const void *matchinfo, |
1402 | int offset, | |
1403 | unsigned int protoff, | |
cff533ac | 1404 | bool *hotdrop) |
1da177e4 LT |
1405 | { |
1406 | struct icmp6hdr _icmp, *ic; | |
1407 | const struct ip6t_icmp *icmpinfo = matchinfo; | |
1408 | ||
1409 | /* Must not be a fragment. */ | |
1410 | if (offset) | |
1d93a9cb | 1411 | return false; |
1da177e4 LT |
1412 | |
1413 | ic = skb_header_pointer(skb, protoff, sizeof(_icmp), &_icmp); | |
1414 | if (ic == NULL) { | |
1415 | /* We've been asked to examine this packet, and we | |
1416 | can't. Hence, no choice but to drop. */ | |
1417 | duprintf("Dropping evil ICMP tinygram.\n"); | |
cff533ac | 1418 | *hotdrop = true; |
1d93a9cb | 1419 | return false; |
1da177e4 LT |
1420 | } |
1421 | ||
1422 | return icmp6_type_code_match(icmpinfo->type, | |
1423 | icmpinfo->code[0], | |
1424 | icmpinfo->code[1], | |
1425 | ic->icmp6_type, ic->icmp6_code, | |
1426 | !!(icmpinfo->invflags&IP6T_ICMP_INV)); | |
1427 | } | |
1428 | ||
1429 | /* Called when user tries to insert an entry of this type. */ | |
ccb79bdc | 1430 | static bool |
1da177e4 | 1431 | icmp6_checkentry(const char *tablename, |
2e4e6a17 | 1432 | const void *entry, |
c4986734 | 1433 | const struct xt_match *match, |
1da177e4 | 1434 | void *matchinfo, |
1da177e4 LT |
1435 | unsigned int hook_mask) |
1436 | { | |
1437 | const struct ip6t_icmp *icmpinfo = matchinfo; | |
1438 | ||
7f939713 PM |
1439 | /* Must specify no unknown invflags */ |
1440 | return !(icmpinfo->invflags & ~IP6T_ICMP_INV); | |
1da177e4 LT |
1441 | } |
1442 | ||
1443 | /* The built-in targets: standard (NULL) and error. */ | |
9f15c530 | 1444 | static struct xt_target ip6t_standard_target __read_mostly = { |
1da177e4 | 1445 | .name = IP6T_STANDARD_TARGET, |
7f939713 | 1446 | .targetsize = sizeof(int), |
a45049c5 | 1447 | .family = AF_INET6, |
1da177e4 LT |
1448 | }; |
1449 | ||
9f15c530 | 1450 | static struct xt_target ip6t_error_target __read_mostly = { |
1da177e4 LT |
1451 | .name = IP6T_ERROR_TARGET, |
1452 | .target = ip6t_error, | |
7f939713 | 1453 | .targetsize = IP6T_FUNCTION_MAXNAMELEN, |
a45049c5 | 1454 | .family = AF_INET6, |
1da177e4 LT |
1455 | }; |
1456 | ||
1457 | static struct nf_sockopt_ops ip6t_sockopts = { | |
1458 | .pf = PF_INET6, | |
1459 | .set_optmin = IP6T_BASE_CTL, | |
1460 | .set_optmax = IP6T_SO_SET_MAX+1, | |
1461 | .set = do_ip6t_set_ctl, | |
1462 | .get_optmin = IP6T_BASE_CTL, | |
1463 | .get_optmax = IP6T_SO_GET_MAX+1, | |
1464 | .get = do_ip6t_get_ctl, | |
16fcec35 | 1465 | .owner = THIS_MODULE, |
1da177e4 LT |
1466 | }; |
1467 | ||
9f15c530 | 1468 | static struct xt_match icmp6_matchstruct __read_mostly = { |
1da177e4 LT |
1469 | .name = "icmp6", |
1470 | .match = &icmp6_match, | |
7f939713 PM |
1471 | .matchsize = sizeof(struct ip6t_icmp), |
1472 | .checkentry = icmp6_checkentry, | |
1473 | .proto = IPPROTO_ICMPV6, | |
a45049c5 | 1474 | .family = AF_INET6, |
1da177e4 LT |
1475 | }; |
1476 | ||
65b4b4e8 | 1477 | static int __init ip6_tables_init(void) |
1da177e4 LT |
1478 | { |
1479 | int ret; | |
1480 | ||
0eff66e6 PM |
1481 | ret = xt_proto_init(AF_INET6); |
1482 | if (ret < 0) | |
1483 | goto err1; | |
2e4e6a17 | 1484 | |
1da177e4 | 1485 | /* Noone else will be downing sem now, so we won't sleep */ |
0eff66e6 PM |
1486 | ret = xt_register_target(&ip6t_standard_target); |
1487 | if (ret < 0) | |
1488 | goto err2; | |
1489 | ret = xt_register_target(&ip6t_error_target); | |
1490 | if (ret < 0) | |
1491 | goto err3; | |
1492 | ret = xt_register_match(&icmp6_matchstruct); | |
1493 | if (ret < 0) | |
1494 | goto err4; | |
1da177e4 LT |
1495 | |
1496 | /* Register setsockopt */ | |
1497 | ret = nf_register_sockopt(&ip6t_sockopts); | |
0eff66e6 PM |
1498 | if (ret < 0) |
1499 | goto err5; | |
1da177e4 | 1500 | |
a887c1c1 | 1501 | printk(KERN_INFO "ip6_tables: (C) 2000-2006 Netfilter Core Team\n"); |
1da177e4 | 1502 | return 0; |
0eff66e6 PM |
1503 | |
1504 | err5: | |
1505 | xt_unregister_match(&icmp6_matchstruct); | |
1506 | err4: | |
1507 | xt_unregister_target(&ip6t_error_target); | |
1508 | err3: | |
1509 | xt_unregister_target(&ip6t_standard_target); | |
1510 | err2: | |
1511 | xt_proto_fini(AF_INET6); | |
1512 | err1: | |
1513 | return ret; | |
1da177e4 LT |
1514 | } |
1515 | ||
65b4b4e8 | 1516 | static void __exit ip6_tables_fini(void) |
1da177e4 LT |
1517 | { |
1518 | nf_unregister_sockopt(&ip6t_sockopts); | |
a45049c5 PNA |
1519 | xt_unregister_match(&icmp6_matchstruct); |
1520 | xt_unregister_target(&ip6t_error_target); | |
1521 | xt_unregister_target(&ip6t_standard_target); | |
2e4e6a17 | 1522 | xt_proto_fini(AF_INET6); |
1da177e4 LT |
1523 | } |
1524 | ||
e674d0f3 | 1525 | /* |
b777e0ce PM |
1526 | * find the offset to specified header or the protocol number of last header |
1527 | * if target < 0. "last header" is transport protocol header, ESP, or | |
1528 | * "No next header". | |
1529 | * | |
1530 | * If target header is found, its offset is set in *offset and return protocol | |
1531 | * number. Otherwise, return -1. | |
1532 | * | |
6d381634 PM |
1533 | * If the first fragment doesn't contain the final protocol header or |
1534 | * NEXTHDR_NONE it is considered invalid. | |
1535 | * | |
b777e0ce PM |
1536 | * Note that non-1st fragment is special case that "the protocol number |
1537 | * of last header" is "next header" field in Fragment header. In this case, | |
1538 | * *offset is meaningless and fragment offset is stored in *fragoff if fragoff | |
1539 | * isn't NULL. | |
e674d0f3 | 1540 | * |
e674d0f3 | 1541 | */ |
b777e0ce PM |
1542 | int ipv6_find_hdr(const struct sk_buff *skb, unsigned int *offset, |
1543 | int target, unsigned short *fragoff) | |
e674d0f3 | 1544 | { |
6b88dd96 | 1545 | unsigned int start = skb_network_offset(skb) + sizeof(struct ipv6hdr); |
0660e03f | 1546 | u8 nexthdr = ipv6_hdr(skb)->nexthdr; |
e674d0f3 YK |
1547 | unsigned int len = skb->len - start; |
1548 | ||
b777e0ce PM |
1549 | if (fragoff) |
1550 | *fragoff = 0; | |
1551 | ||
e674d0f3 YK |
1552 | while (nexthdr != target) { |
1553 | struct ipv6_opt_hdr _hdr, *hp; | |
1554 | unsigned int hdrlen; | |
1555 | ||
b777e0ce PM |
1556 | if ((!ipv6_ext_hdr(nexthdr)) || nexthdr == NEXTHDR_NONE) { |
1557 | if (target < 0) | |
1558 | break; | |
6d381634 | 1559 | return -ENOENT; |
b777e0ce PM |
1560 | } |
1561 | ||
e674d0f3 YK |
1562 | hp = skb_header_pointer(skb, start, sizeof(_hdr), &_hdr); |
1563 | if (hp == NULL) | |
6d381634 | 1564 | return -EBADMSG; |
e674d0f3 | 1565 | if (nexthdr == NEXTHDR_FRAGMENT) { |
e69a4adc AV |
1566 | unsigned short _frag_off; |
1567 | __be16 *fp; | |
e674d0f3 YK |
1568 | fp = skb_header_pointer(skb, |
1569 | start+offsetof(struct frag_hdr, | |
1570 | frag_off), | |
1571 | sizeof(_frag_off), | |
1572 | &_frag_off); | |
1573 | if (fp == NULL) | |
6d381634 | 1574 | return -EBADMSG; |
e674d0f3 | 1575 | |
b777e0ce PM |
1576 | _frag_off = ntohs(*fp) & ~0x7; |
1577 | if (_frag_off) { | |
1578 | if (target < 0 && | |
1579 | ((!ipv6_ext_hdr(hp->nexthdr)) || | |
337dde79 | 1580 | hp->nexthdr == NEXTHDR_NONE)) { |
b777e0ce PM |
1581 | if (fragoff) |
1582 | *fragoff = _frag_off; | |
1583 | return hp->nexthdr; | |
1584 | } | |
6d381634 | 1585 | return -ENOENT; |
b777e0ce | 1586 | } |
e674d0f3 YK |
1587 | hdrlen = 8; |
1588 | } else if (nexthdr == NEXTHDR_AUTH) | |
1ab1457c | 1589 | hdrlen = (hp->hdrlen + 2) << 2; |
e674d0f3 | 1590 | else |
1ab1457c | 1591 | hdrlen = ipv6_optlen(hp); |
e674d0f3 YK |
1592 | |
1593 | nexthdr = hp->nexthdr; | |
1594 | len -= hdrlen; | |
1595 | start += hdrlen; | |
1596 | } | |
1597 | ||
1598 | *offset = start; | |
b777e0ce | 1599 | return nexthdr; |
e674d0f3 YK |
1600 | } |
1601 | ||
1da177e4 LT |
1602 | EXPORT_SYMBOL(ip6t_register_table); |
1603 | EXPORT_SYMBOL(ip6t_unregister_table); | |
1604 | EXPORT_SYMBOL(ip6t_do_table); | |
1da177e4 | 1605 | EXPORT_SYMBOL(ip6t_ext_hdr); |
e674d0f3 | 1606 | EXPORT_SYMBOL(ipv6_find_hdr); |
1da177e4 | 1607 | |
65b4b4e8 AM |
1608 | module_init(ip6_tables_init); |
1609 | module_exit(ip6_tables_fini); |