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Merge tag 'rproc-v6.14' of git://git.kernel.org/pub/scm/linux/kernel/git/remoteproc...
[linux.git] / net / ipv6 / netfilter / ip6_tables.c
blob7d5602950ae72ae7d7c7e5b2c7ab5f33efa1501a
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Packet matching code.
4 *
5 * Copyright (C) 1999 Paul `Rusty' Russell & Michael J. Neuling
6 * Copyright (C) 2000-2005 Netfilter Core Team <coreteam@netfilter.org>
7 * Copyright (c) 2006-2010 Patrick McHardy <kaber@trash.net>
8 */
9
10 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
11
12 #include <linux/kernel.h>
13 #include <linux/capability.h>
14 #include <linux/in.h>
15 #include <linux/skbuff.h>
16 #include <linux/kmod.h>
17 #include <linux/vmalloc.h>
18 #include <linux/netdevice.h>
19 #include <linux/module.h>
20 #include <linux/poison.h>
21 #include <net/ipv6.h>
22 #include <net/compat.h>
23 #include <linux/uaccess.h>
24 #include <linux/mutex.h>
25 #include <linux/proc_fs.h>
26 #include <linux/err.h>
27 #include <linux/cpumask.h>
28
29 #include <linux/netfilter_ipv6/ip6_tables.h>
30 #include <linux/netfilter/x_tables.h>
31 #include <net/netfilter/nf_log.h>
32 #include "../../netfilter/xt_repldata.h"
33
34 MODULE_LICENSE("GPL");
35 MODULE_AUTHOR("Netfilter Core Team <coreteam@netfilter.org>");
36 MODULE_DESCRIPTION("IPv6 packet filter");
37
38 void *ip6t_alloc_initial_table(const struct xt_table *info)
39 {
40 return xt_alloc_initial_table(ip6t, IP6T);
41 }
42 EXPORT_SYMBOL_GPL(ip6t_alloc_initial_table);
43
44 /* Returns whether matches rule or not. */
45 /* Performance critical - called for every packet */
46 static inline bool
47 ip6_packet_match(const struct sk_buff *skb,
48 const char *indev,
49 const char *outdev,
50 const struct ip6t_ip6 *ip6info,
51 unsigned int *protoff,
52 u16 *fragoff, bool *hotdrop)
53 {
54 unsigned long ret;
55 const struct ipv6hdr *ipv6 = ipv6_hdr(skb);
56
57 if (NF_INVF(ip6info, IP6T_INV_SRCIP,
58 ipv6_masked_addr_cmp(&ipv6->saddr, &ip6info->smsk,
59 &ip6info->src)) ||
60 NF_INVF(ip6info, IP6T_INV_DSTIP,
61 ipv6_masked_addr_cmp(&ipv6->daddr, &ip6info->dmsk,
62 &ip6info->dst)))
63 return false;
64
65 ret = ifname_compare_aligned(indev, ip6info->iniface, ip6info->iniface_mask);
66
67 if (NF_INVF(ip6info, IP6T_INV_VIA_IN, ret != 0))
68 return false;
69
70 ret = ifname_compare_aligned(outdev, ip6info->outiface, ip6info->outiface_mask);
71
72 if (NF_INVF(ip6info, IP6T_INV_VIA_OUT, ret != 0))
73 return false;
74
75 /* ... might want to do something with class and flowlabel here ... */
76
77 /* look for the desired protocol header */
78 if (ip6info->flags & IP6T_F_PROTO) {
79 int protohdr;
80 unsigned short _frag_off;
81
82 protohdr = ipv6_find_hdr(skb, protoff, -1, &_frag_off, NULL);
83 if (protohdr < 0) {
84 if (_frag_off == 0)
85 *hotdrop = true;
86 return false;
87 }
88 *fragoff = _frag_off;
89
90 if (ip6info->proto == protohdr) {
91 if (ip6info->invflags & IP6T_INV_PROTO)
92 return false;
93
94 return true;
95 }
96
97 /* We need match for the '-p all', too! */
98 if ((ip6info->proto != 0) &&
99 !(ip6info->invflags & IP6T_INV_PROTO))
100 return false;
101 }
102 return true;
103 }
104
105 /* should be ip6 safe */
106 static bool
107 ip6_checkentry(const struct ip6t_ip6 *ipv6)
108 {
109 if (ipv6->flags & ~IP6T_F_MASK)
110 return false;
111 if (ipv6->invflags & ~IP6T_INV_MASK)
112 return false;
113
114 return true;
115 }
116
117 static unsigned int
118 ip6t_error(struct sk_buff *skb, const struct xt_action_param *par)
119 {
120 net_info_ratelimited("error: `%s'\n", (const char *)par->targinfo);
121
122 return NF_DROP;
123 }
124
125 static inline struct ip6t_entry *
126 get_entry(const void *base, unsigned int offset)
127 {
128 return (struct ip6t_entry *)(base + offset);
129 }
130
131 /* All zeroes == unconditional rule. */
132 /* Mildly perf critical (only if packet tracing is on) */
133 static inline bool unconditional(const struct ip6t_entry *e)
134 {
135 static const struct ip6t_ip6 uncond;
136
137 return e->target_offset == sizeof(struct ip6t_entry) &&
138 memcmp(&e->ipv6, &uncond, sizeof(uncond)) == 0;
139 }
140
141 static inline const struct xt_entry_target *
142 ip6t_get_target_c(const struct ip6t_entry *e)
143 {
144 return ip6t_get_target((struct ip6t_entry *)e);
145 }
146
147 #if IS_ENABLED(CONFIG_NETFILTER_XT_TARGET_TRACE)
148 /* This cries for unification! */
149 static const char *const hooknames[] = {
150 [NF_INET_PRE_ROUTING] = "PREROUTING",
151 [NF_INET_LOCAL_IN] = "INPUT",
152 [NF_INET_FORWARD] = "FORWARD",
153 [NF_INET_LOCAL_OUT] = "OUTPUT",
154 [NF_INET_POST_ROUTING] = "POSTROUTING",
155 };
156
157 enum nf_ip_trace_comments {
158 NF_IP6_TRACE_COMMENT_RULE,
159 NF_IP6_TRACE_COMMENT_RETURN,
160 NF_IP6_TRACE_COMMENT_POLICY,
161 };
162
163 static const char *const comments[] = {
164 [NF_IP6_TRACE_COMMENT_RULE] = "rule",
165 [NF_IP6_TRACE_COMMENT_RETURN] = "return",
166 [NF_IP6_TRACE_COMMENT_POLICY] = "policy",
167 };
168
169 static const struct nf_loginfo trace_loginfo = {
170 .type = NF_LOG_TYPE_LOG,
171 .u = {
172 .log = {
173 .level = LOGLEVEL_WARNING,
174 .logflags = NF_LOG_DEFAULT_MASK,
175 },
176 },
177 };
178
179 /* Mildly perf critical (only if packet tracing is on) */
180 static inline int
181 get_chainname_rulenum(const struct ip6t_entry *s, const struct ip6t_entry *e,
182 const char *hookname, const char **chainname,
183 const char **comment, unsigned int *rulenum)
184 {
185 const struct xt_standard_target *t = (void *)ip6t_get_target_c(s);
186
187 if (strcmp(t->target.u.kernel.target->name, XT_ERROR_TARGET) == 0) {
188 /* Head of user chain: ERROR target with chainname */
189 *chainname = t->target.data;
190 (*rulenum) = 0;
191 } else if (s == e) {
192 (*rulenum)++;
193
194 if (unconditional(s) &&
195 strcmp(t->target.u.kernel.target->name,
196 XT_STANDARD_TARGET) == 0 &&
197 t->verdict < 0) {
198 /* Tail of chains: STANDARD target (return/policy) */
199 *comment = *chainname == hookname
200 ? comments[NF_IP6_TRACE_COMMENT_POLICY]
201 : comments[NF_IP6_TRACE_COMMENT_RETURN];
202 }
203 return 1;
204 } else
205 (*rulenum)++;
206
207 return 0;
208 }
209
210 static void trace_packet(struct net *net,
211 const struct sk_buff *skb,
212 unsigned int hook,
213 const struct net_device *in,
214 const struct net_device *out,
215 const char *tablename,
216 const struct xt_table_info *private,
217 const struct ip6t_entry *e)
218 {
219 const struct ip6t_entry *root;
220 const char *hookname, *chainname, *comment;
221 const struct ip6t_entry *iter;
222 unsigned int rulenum = 0;
223
224 root = get_entry(private->entries, private->hook_entry[hook]);
225
226 hookname = chainname = hooknames[hook];
227 comment = comments[NF_IP6_TRACE_COMMENT_RULE];
228
229 xt_entry_foreach(iter, root, private->size - private->hook_entry[hook])
230 if (get_chainname_rulenum(iter, e, hookname,
231 &chainname, &comment, &rulenum) != 0)
232 break;
233
234 nf_log_trace(net, AF_INET6, hook, skb, in, out, &trace_loginfo,
235 "TRACE: %s:%s:%s:%u ",
236 tablename, chainname, comment, rulenum);
237 }
238 #endif
239
240 static inline struct ip6t_entry *
241 ip6t_next_entry(const struct ip6t_entry *entry)
242 {
243 return (void *)entry + entry->next_offset;
244 }
245
246 /* Returns one of the generic firewall policies, like NF_ACCEPT. */
247 unsigned int
248 ip6t_do_table(void *priv, struct sk_buff *skb,
249 const struct nf_hook_state *state)
250 {
251 const struct xt_table *table = priv;
252 unsigned int hook = state->hook;
253 static const char nulldevname[IFNAMSIZ] __attribute__((aligned(sizeof(long))));
254 /* Initializing verdict to NF_DROP keeps gcc happy. */
255 unsigned int verdict = NF_DROP;
256 const char *indev, *outdev;
257 const void *table_base;
258 struct ip6t_entry *e, **jumpstack;
259 unsigned int stackidx, cpu;
260 const struct xt_table_info *private;
261 struct xt_action_param acpar;
262 unsigned int addend;
263
264 /* Initialization */
265 stackidx = 0;
266 indev = state->in ? state->in->name : nulldevname;
267 outdev = state->out ? state->out->name : nulldevname;
268 /* We handle fragments by dealing with the first fragment as
269 * if it was a normal packet. All other fragments are treated
270 * normally, except that they will NEVER match rules that ask
271 * things we don't know, ie. tcp syn flag or ports). If the
272 * rule is also a fragment-specific rule, non-fragments won't
273 * match it. */
274 acpar.fragoff = 0;
275 acpar.hotdrop = false;
276 acpar.state = state;
277
278 WARN_ON(!(table->valid_hooks & (1 << hook)));
279
280 local_bh_disable();
281 addend = xt_write_recseq_begin();
282 private = READ_ONCE(table->private); /* Address dependency. */
283 cpu = smp_processor_id();
284 table_base = private->entries;
285 jumpstack = (struct ip6t_entry **)private->jumpstack[cpu];
286
287 /* Switch to alternate jumpstack if we're being invoked via TEE.
288 * TEE issues XT_CONTINUE verdict on original skb so we must not
289 * clobber the jumpstack.
290 *
291 * For recursion via REJECT or SYNPROXY the stack will be clobbered
292 * but it is no problem since absolute verdict is issued by these.
293 */
294 if (static_key_false(&xt_tee_enabled))
295 jumpstack += private->stacksize * __this_cpu_read(nf_skb_duplicated);
296
297 e = get_entry(table_base, private->hook_entry[hook]);
298
299 do {
300 const struct xt_entry_target *t;
301 const struct xt_entry_match *ematch;
302 struct xt_counters *counter;
303
304 WARN_ON(!e);
305 acpar.thoff = 0;
306 if (!ip6_packet_match(skb, indev, outdev, &e->ipv6,
307 &acpar.thoff, &acpar.fragoff, &acpar.hotdrop)) {
308 no_match:
309 e = ip6t_next_entry(e);
310 continue;
311 }
312
313 xt_ematch_foreach(ematch, e) {
314 acpar.match = ematch->u.kernel.match;
315 acpar.matchinfo = ematch->data;
316 if (!acpar.match->match(skb, &acpar))
317 goto no_match;
318 }
319
320 counter = xt_get_this_cpu_counter(&e->counters);
321 ADD_COUNTER(*counter, skb->len, 1);
322
323 t = ip6t_get_target_c(e);
324 WARN_ON(!t->u.kernel.target);
325
326 #if IS_ENABLED(CONFIG_NETFILTER_XT_TARGET_TRACE)
327 /* The packet is traced: log it */
328 if (unlikely(skb->nf_trace))
329 trace_packet(state->net, skb, hook, state->in,
330 state->out, table->name, private, e);
331 #endif
332 /* Standard target? */
333 if (!t->u.kernel.target->target) {
334 int v;
335
336 v = ((struct xt_standard_target *)t)->verdict;
337 if (v < 0) {
338 /* Pop from stack? */
339 if (v != XT_RETURN) {
340 verdict = (unsigned int)(-v) - 1;
341 break;
342 }
343 if (stackidx == 0)
344 e = get_entry(table_base,
345 private->underflow[hook]);
346 else
347 e = ip6t_next_entry(jumpstack[--stackidx]);
348 continue;
349 }
350 if (table_base + v != ip6t_next_entry(e) &&
351 !(e->ipv6.flags & IP6T_F_GOTO)) {
352 if (unlikely(stackidx >= private->stacksize)) {
353 verdict = NF_DROP;
354 break;
355 }
356 jumpstack[stackidx++] = e;
357 }
358
359 e = get_entry(table_base, v);
360 continue;
361 }
362
363 acpar.target = t->u.kernel.target;
364 acpar.targinfo = t->data;
365
366 verdict = t->u.kernel.target->target(skb, &acpar);
367 if (verdict == XT_CONTINUE)
368 e = ip6t_next_entry(e);
369 else
370 /* Verdict */
371 break;
372 } while (!acpar.hotdrop);
373
374 xt_write_recseq_end(addend);
375 local_bh_enable();
376
377 if (acpar.hotdrop)
378 return NF_DROP;
379 else return verdict;
380 }
381
382 /* Figures out from what hook each rule can be called: returns 0 if
383 there are loops. Puts hook bitmask in comefrom. */
384 static int
385 mark_source_chains(const struct xt_table_info *newinfo,
386 unsigned int valid_hooks, void *entry0,
387 unsigned int *offsets)
388 {
389 unsigned int hook;
390
391 /* No recursion; use packet counter to save back ptrs (reset
392 to 0 as we leave), and comefrom to save source hook bitmask */
393 for (hook = 0; hook < NF_INET_NUMHOOKS; hook++) {
394 unsigned int pos = newinfo->hook_entry[hook];
395 struct ip6t_entry *e = entry0 + pos;
396
397 if (!(valid_hooks & (1 << hook)))
398 continue;
399
400 /* Set initial back pointer. */
401 e->counters.pcnt = pos;
402
403 for (;;) {
404 const struct xt_standard_target *t
405 = (void *)ip6t_get_target_c(e);
406 int visited = e->comefrom & (1 << hook);
407
408 if (e->comefrom & (1 << NF_INET_NUMHOOKS))
409 return 0;
410
411 e->comefrom |= ((1 << hook) | (1 << NF_INET_NUMHOOKS));
412
413 /* Unconditional return/END. */
414 if ((unconditional(e) &&
415 (strcmp(t->target.u.user.name,
416 XT_STANDARD_TARGET) == 0) &&
417 t->verdict < 0) || visited) {
418 unsigned int oldpos, size;
419
420 /* Return: backtrack through the last
421 big jump. */
422 do {
423 e->comefrom ^= (1<<NF_INET_NUMHOOKS);
424 oldpos = pos;
425 pos = e->counters.pcnt;
426 e->counters.pcnt = 0;
427
428 /* We're at the start. */
429 if (pos == oldpos)
430 goto next;
431
432 e = entry0 + pos;
433 } while (oldpos == pos + e->next_offset);
434
435 /* Move along one */
436 size = e->next_offset;
437 e = entry0 + pos + size;
438 if (pos + size >= newinfo->size)
439 return 0;
440 e->counters.pcnt = pos;
441 pos += size;
442 } else {
443 int newpos = t->verdict;
444
445 if (strcmp(t->target.u.user.name,
446 XT_STANDARD_TARGET) == 0 &&
447 newpos >= 0) {
448 /* This a jump; chase it. */
449 if (!xt_find_jump_offset(offsets, newpos,
450 newinfo->number))
451 return 0;
452 } else {
453 /* ... this is a fallthru */
454 newpos = pos + e->next_offset;
455 if (newpos >= newinfo->size)
456 return 0;
457 }
458 e = entry0 + newpos;
459 e->counters.pcnt = pos;
460 pos = newpos;
461 }
462 }
463 next: ;
464 }
465 return 1;
466 }
467
468 static void cleanup_match(struct xt_entry_match *m, struct net *net)
469 {
470 struct xt_mtdtor_param par;
471
472 par.net = net;
473 par.match = m->u.kernel.match;
474 par.matchinfo = m->data;
475 par.family = NFPROTO_IPV6;
476 if (par.match->destroy != NULL)
477 par.match->destroy(&par);
478 module_put(par.match->me);
479 }
480
481 static int check_match(struct xt_entry_match *m, struct xt_mtchk_param *par)
482 {
483 const struct ip6t_ip6 *ipv6 = par->entryinfo;
484
485 par->match = m->u.kernel.match;
486 par->matchinfo = m->data;
487
488 return xt_check_match(par, m->u.match_size - sizeof(*m),
489 ipv6->proto, ipv6->invflags & IP6T_INV_PROTO);
490 }
491
492 static int
493 find_check_match(struct xt_entry_match *m, struct xt_mtchk_param *par)
494 {
495 struct xt_match *match;
496 int ret;
497
498 match = xt_request_find_match(NFPROTO_IPV6, m->u.user.name,
499 m->u.user.revision);
500 if (IS_ERR(match))
501 return PTR_ERR(match);
502
503 m->u.kernel.match = match;
504
505 ret = check_match(m, par);
506 if (ret)
507 goto err;
508
509 return 0;
510 err:
511 module_put(m->u.kernel.match->me);
512 return ret;
513 }
514
515 static int check_target(struct ip6t_entry *e, struct net *net, const char *name)
516 {
517 struct xt_entry_target *t = ip6t_get_target(e);
518 struct xt_tgchk_param par = {
519 .net = net,
520 .table = name,
521 .entryinfo = e,
522 .target = t->u.kernel.target,
523 .targinfo = t->data,
524 .hook_mask = e->comefrom,
525 .family = NFPROTO_IPV6,
526 };
527
528 return xt_check_target(&par, t->u.target_size - sizeof(*t),
529 e->ipv6.proto,
530 e->ipv6.invflags & IP6T_INV_PROTO);
531 }
532
533 static int
534 find_check_entry(struct ip6t_entry *e, struct net *net, const char *name,
535 unsigned int size,
536 struct xt_percpu_counter_alloc_state *alloc_state)
537 {
538 struct xt_entry_target *t;
539 struct xt_target *target;
540 int ret;
541 unsigned int j;
542 struct xt_mtchk_param mtpar;
543 struct xt_entry_match *ematch;
544
545 if (!xt_percpu_counter_alloc(alloc_state, &e->counters))
546 return -ENOMEM;
547
548 j = 0;
549 memset(&mtpar, 0, sizeof(mtpar));
550 mtpar.net = net;
551 mtpar.table = name;
552 mtpar.entryinfo = &e->ipv6;
553 mtpar.hook_mask = e->comefrom;
554 mtpar.family = NFPROTO_IPV6;
555 xt_ematch_foreach(ematch, e) {
556 ret = find_check_match(ematch, &mtpar);
557 if (ret != 0)
558 goto cleanup_matches;
559 ++j;
560 }
561
562 t = ip6t_get_target(e);
563 target = xt_request_find_target(NFPROTO_IPV6, t->u.user.name,
564 t->u.user.revision);
565 if (IS_ERR(target)) {
566 ret = PTR_ERR(target);
567 goto cleanup_matches;
568 }
569 t->u.kernel.target = target;
570
571 ret = check_target(e, net, name);
572 if (ret)
573 goto err;
574 return 0;
575 err:
576 module_put(t->u.kernel.target->me);
577 cleanup_matches:
578 xt_ematch_foreach(ematch, e) {
579 if (j-- == 0)
580 break;
581 cleanup_match(ematch, net);
582 }
583
584 xt_percpu_counter_free(&e->counters);
585
586 return ret;
587 }
588
589 static bool check_underflow(const struct ip6t_entry *e)
590 {
591 const struct xt_entry_target *t;
592 unsigned int verdict;
593
594 if (!unconditional(e))
595 return false;
596 t = ip6t_get_target_c(e);
597 if (strcmp(t->u.user.name, XT_STANDARD_TARGET) != 0)
598 return false;
599 verdict = ((struct xt_standard_target *)t)->verdict;
600 verdict = -verdict - 1;
601 return verdict == NF_DROP || verdict == NF_ACCEPT;
602 }
603
604 static int
605 check_entry_size_and_hooks(struct ip6t_entry *e,
606 struct xt_table_info *newinfo,
607 const unsigned char *base,
608 const unsigned char *limit,
609 const unsigned int *hook_entries,
610 const unsigned int *underflows,
611 unsigned int valid_hooks)
612 {
613 unsigned int h;
614 int err;
615
616 if ((unsigned long)e % __alignof__(struct ip6t_entry) != 0 ||
617 (unsigned char *)e + sizeof(struct ip6t_entry) >= limit ||
618 (unsigned char *)e + e->next_offset > limit)
619 return -EINVAL;
620
621 if (e->next_offset
622 < sizeof(struct ip6t_entry) + sizeof(struct xt_entry_target))
623 return -EINVAL;
624
625 if (!ip6_checkentry(&e->ipv6))
626 return -EINVAL;
627
628 err = xt_check_entry_offsets(e, e->elems, e->target_offset,
629 e->next_offset);
630 if (err)
631 return err;
632
633 /* Check hooks & underflows */
634 for (h = 0; h < NF_INET_NUMHOOKS; h++) {
635 if (!(valid_hooks & (1 << h)))
636 continue;
637 if ((unsigned char *)e - base == hook_entries[h])
638 newinfo->hook_entry[h] = hook_entries[h];
639 if ((unsigned char *)e - base == underflows[h]) {
640 if (!check_underflow(e))
641 return -EINVAL;
642
643 newinfo->underflow[h] = underflows[h];
644 }
645 }
646
647 /* Clear counters and comefrom */
648 e->counters = ((struct xt_counters) { 0, 0 });
649 e->comefrom = 0;
650 return 0;
651 }
652
653 static void cleanup_entry(struct ip6t_entry *e, struct net *net)
654 {
655 struct xt_tgdtor_param par;
656 struct xt_entry_target *t;
657 struct xt_entry_match *ematch;
658
659 /* Cleanup all matches */
660 xt_ematch_foreach(ematch, e)
661 cleanup_match(ematch, net);
662 t = ip6t_get_target(e);
663
664 par.net = net;
665 par.target = t->u.kernel.target;
666 par.targinfo = t->data;
667 par.family = NFPROTO_IPV6;
668 if (par.target->destroy != NULL)
669 par.target->destroy(&par);
670 module_put(par.target->me);
671 xt_percpu_counter_free(&e->counters);
672 }
673
674 /* Checks and translates the user-supplied table segment (held in
675 newinfo) */
676 static int
677 translate_table(struct net *net, struct xt_table_info *newinfo, void *entry0,
678 const struct ip6t_replace *repl)
679 {
680 struct xt_percpu_counter_alloc_state alloc_state = { 0 };
681 struct ip6t_entry *iter;
682 unsigned int *offsets;
683 unsigned int i;
684 int ret = 0;
685
686 newinfo->size = repl->size;
687 newinfo->number = repl->num_entries;
688
689 /* Init all hooks to impossible value. */
690 for (i = 0; i < NF_INET_NUMHOOKS; i++) {
691 newinfo->hook_entry[i] = 0xFFFFFFFF;
692 newinfo->underflow[i] = 0xFFFFFFFF;
693 }
694
695 offsets = xt_alloc_entry_offsets(newinfo->number);
696 if (!offsets)
697 return -ENOMEM;
698 i = 0;
699 /* Walk through entries, checking offsets. */
700 xt_entry_foreach(iter, entry0, newinfo->size) {
701 ret = check_entry_size_and_hooks(iter, newinfo, entry0,
702 entry0 + repl->size,
703 repl->hook_entry,
704 repl->underflow,
705 repl->valid_hooks);
706 if (ret != 0)
707 goto out_free;
708 if (i < repl->num_entries)
709 offsets[i] = (void *)iter - entry0;
710 ++i;
711 if (strcmp(ip6t_get_target(iter)->u.user.name,
712 XT_ERROR_TARGET) == 0)
713 ++newinfo->stacksize;
714 }
715
716 ret = -EINVAL;
717 if (i != repl->num_entries)
718 goto out_free;
719
720 ret = xt_check_table_hooks(newinfo, repl->valid_hooks);
721 if (ret)
722 goto out_free;
723
724 if (!mark_source_chains(newinfo, repl->valid_hooks, entry0, offsets)) {
725 ret = -ELOOP;
726 goto out_free;
727 }
728 kvfree(offsets);
729
730 /* Finally, each sanity check must pass */
731 i = 0;
732 xt_entry_foreach(iter, entry0, newinfo->size) {
733 ret = find_check_entry(iter, net, repl->name, repl->size,
734 &alloc_state);
735 if (ret != 0)
736 break;
737 ++i;
738 }
739
740 if (ret != 0) {
741 xt_entry_foreach(iter, entry0, newinfo->size) {
742 if (i-- == 0)
743 break;
744 cleanup_entry(iter, net);
745 }
746 return ret;
747 }
748
749 return ret;
750 out_free:
751 kvfree(offsets);
752 return ret;
753 }
754
755 static void
756 get_counters(const struct xt_table_info *t,
757 struct xt_counters counters[])
758 {
759 struct ip6t_entry *iter;
760 unsigned int cpu;
761 unsigned int i;
762
763 for_each_possible_cpu(cpu) {
764 seqcount_t *s = &per_cpu(xt_recseq, cpu);
765
766 i = 0;
767 xt_entry_foreach(iter, t->entries, t->size) {
768 struct xt_counters *tmp;
769 u64 bcnt, pcnt;
770 unsigned int start;
771
772 tmp = xt_get_per_cpu_counter(&iter->counters, cpu);
773 do {
774 start = read_seqcount_begin(s);
775 bcnt = tmp->bcnt;
776 pcnt = tmp->pcnt;
777 } while (read_seqcount_retry(s, start));
778
779 ADD_COUNTER(counters[i], bcnt, pcnt);
780 ++i;
781 cond_resched();
782 }
783 }
784 }
785
786 static void get_old_counters(const struct xt_table_info *t,
787 struct xt_counters counters[])
788 {
789 struct ip6t_entry *iter;
790 unsigned int cpu, i;
791
792 for_each_possible_cpu(cpu) {
793 i = 0;
794 xt_entry_foreach(iter, t->entries, t->size) {
795 const struct xt_counters *tmp;
796
797 tmp = xt_get_per_cpu_counter(&iter->counters, cpu);
798 ADD_COUNTER(counters[i], tmp->bcnt, tmp->pcnt);
799 ++i;
800 }
801 cond_resched();
802 }
803 }
804
805 static struct xt_counters *alloc_counters(const struct xt_table *table)
806 {
807 unsigned int countersize;
808 struct xt_counters *counters;
809 const struct xt_table_info *private = table->private;
810
811 /* We need atomic snapshot of counters: rest doesn't change
812 (other than comefrom, which userspace doesn't care
813 about). */
814 countersize = sizeof(struct xt_counters) * private->number;
815 counters = vzalloc(countersize);
816
817 if (counters == NULL)
818 return ERR_PTR(-ENOMEM);
819
820 get_counters(private, counters);
821
822 return counters;
823 }
824
825 static int
826 copy_entries_to_user(unsigned int total_size,
827 const struct xt_table *table,
828 void __user *userptr)
829 {
830 unsigned int off, num;
831 const struct ip6t_entry *e;
832 struct xt_counters *counters;
833 const struct xt_table_info *private = table->private;
834 int ret = 0;
835 const void *loc_cpu_entry;
836
837 counters = alloc_counters(table);
838 if (IS_ERR(counters))
839 return PTR_ERR(counters);
840
841 loc_cpu_entry = private->entries;
842
843 /* FIXME: use iterator macros --RR */
844 /* ... then go back and fix counters and names */
845 for (off = 0, num = 0; off < total_size; off += e->next_offset, num++){
846 unsigned int i;
847 const struct xt_entry_match *m;
848 const struct xt_entry_target *t;
849
850 e = loc_cpu_entry + off;
851 if (copy_to_user(userptr + off, e, sizeof(*e))) {
852 ret = -EFAULT;
853 goto free_counters;
854 }
855 if (copy_to_user(userptr + off
856 + offsetof(struct ip6t_entry, counters),
857 &counters[num],
858 sizeof(counters[num])) != 0) {
859 ret = -EFAULT;
860 goto free_counters;
861 }
862
863 for (i = sizeof(struct ip6t_entry);
864 i < e->target_offset;
865 i += m->u.match_size) {
866 m = (void *)e + i;
867
868 if (xt_match_to_user(m, userptr + off + i)) {
869 ret = -EFAULT;
870 goto free_counters;
871 }
872 }
873
874 t = ip6t_get_target_c(e);
875 if (xt_target_to_user(t, userptr + off + e->target_offset)) {
876 ret = -EFAULT;
877 goto free_counters;
878 }
879 }
880
881 free_counters:
882 vfree(counters);
883 return ret;
884 }
885
886 #ifdef CONFIG_NETFILTER_XTABLES_COMPAT
887 static void compat_standard_from_user(void *dst, const void *src)
888 {
889 int v = *(compat_int_t *)src;
890
891 if (v > 0)
892 v += xt_compat_calc_jump(AF_INET6, v);
893 memcpy(dst, &v, sizeof(v));
894 }
895
896 static int compat_standard_to_user(void __user *dst, const void *src)
897 {
898 compat_int_t cv = *(int *)src;
899
900 if (cv > 0)
901 cv -= xt_compat_calc_jump(AF_INET6, cv);
902 return copy_to_user(dst, &cv, sizeof(cv)) ? -EFAULT : 0;
903 }
904
905 static int compat_calc_entry(const struct ip6t_entry *e,
906 const struct xt_table_info *info,
907 const void *base, struct xt_table_info *newinfo)
908 {
909 const struct xt_entry_match *ematch;
910 const struct xt_entry_target *t;
911 unsigned int entry_offset;
912 int off, i, ret;
913
914 off = sizeof(struct ip6t_entry) - sizeof(struct compat_ip6t_entry);
915 entry_offset = (void *)e - base;
916 xt_ematch_foreach(ematch, e)
917 off += xt_compat_match_offset(ematch->u.kernel.match);
918 t = ip6t_get_target_c(e);
919 off += xt_compat_target_offset(t->u.kernel.target);
920 newinfo->size -= off;
921 ret = xt_compat_add_offset(AF_INET6, entry_offset, off);
922 if (ret)
923 return ret;
924
925 for (i = 0; i < NF_INET_NUMHOOKS; i++) {
926 if (info->hook_entry[i] &&
927 (e < (struct ip6t_entry *)(base + info->hook_entry[i])))
928 newinfo->hook_entry[i] -= off;
929 if (info->underflow[i] &&
930 (e < (struct ip6t_entry *)(base + info->underflow[i])))
931 newinfo->underflow[i] -= off;
932 }
933 return 0;
934 }
935
936 static int compat_table_info(const struct xt_table_info *info,
937 struct xt_table_info *newinfo)
938 {
939 struct ip6t_entry *iter;
940 const void *loc_cpu_entry;
941 int ret;
942
943 if (!newinfo || !info)
944 return -EINVAL;
945
946 /* we dont care about newinfo->entries */
947 memcpy(newinfo, info, offsetof(struct xt_table_info, entries));
948 newinfo->initial_entries = 0;
949 loc_cpu_entry = info->entries;
950 ret = xt_compat_init_offsets(AF_INET6, info->number);
951 if (ret)
952 return ret;
953 xt_entry_foreach(iter, loc_cpu_entry, info->size) {
954 ret = compat_calc_entry(iter, info, loc_cpu_entry, newinfo);
955 if (ret != 0)
956 return ret;
957 }
958 return 0;
959 }
960 #endif
961
962 static int get_info(struct net *net, void __user *user, const int *len)
963 {
964 char name[XT_TABLE_MAXNAMELEN];
965 struct xt_table *t;
966 int ret;
967
968 if (*len != sizeof(struct ip6t_getinfo))
969 return -EINVAL;
970
971 if (copy_from_user(name, user, sizeof(name)) != 0)
972 return -EFAULT;
973
974 name[XT_TABLE_MAXNAMELEN-1] = '\0';
975 #ifdef CONFIG_NETFILTER_XTABLES_COMPAT
976 if (in_compat_syscall())
977 xt_compat_lock(AF_INET6);
978 #endif
979 t = xt_request_find_table_lock(net, AF_INET6, name);
980 if (!IS_ERR(t)) {
981 struct ip6t_getinfo info;
982 const struct xt_table_info *private = t->private;
983 #ifdef CONFIG_NETFILTER_XTABLES_COMPAT
984 struct xt_table_info tmp;
985
986 if (in_compat_syscall()) {
987 ret = compat_table_info(private, &tmp);
988 xt_compat_flush_offsets(AF_INET6);
989 private = &tmp;
990 }
991 #endif
992 memset(&info, 0, sizeof(info));
993 info.valid_hooks = t->valid_hooks;
994 memcpy(info.hook_entry, private->hook_entry,
995 sizeof(info.hook_entry));
996 memcpy(info.underflow, private->underflow,
997 sizeof(info.underflow));
998 info.num_entries = private->number;
999 info.size = private->size;
1000 strcpy(info.name, name);
1001
1002 if (copy_to_user(user, &info, *len) != 0)
1003 ret = -EFAULT;
1004 else
1005 ret = 0;
1006
1007 xt_table_unlock(t);
1008 module_put(t->me);
1009 } else
1010 ret = PTR_ERR(t);
1011 #ifdef CONFIG_NETFILTER_XTABLES_COMPAT
1012 if (in_compat_syscall())
1013 xt_compat_unlock(AF_INET6);
1014 #endif
1015 return ret;
1016 }
1017
1018 static int
1019 get_entries(struct net *net, struct ip6t_get_entries __user *uptr,
1020 const int *len)
1021 {
1022 int ret;
1023 struct ip6t_get_entries get;
1024 struct xt_table *t;
1025
1026 if (*len < sizeof(get))
1027 return -EINVAL;
1028 if (copy_from_user(&get, uptr, sizeof(get)) != 0)
1029 return -EFAULT;
1030 if (*len != sizeof(struct ip6t_get_entries) + get.size)
1031 return -EINVAL;
1032
1033 get.name[sizeof(get.name) - 1] = '\0';
1034
1035 t = xt_find_table_lock(net, AF_INET6, get.name);
1036 if (!IS_ERR(t)) {
1037 struct xt_table_info *private = t->private;
1038 if (get.size == private->size)
1039 ret = copy_entries_to_user(private->size,
1040 t, uptr->entrytable);
1041 else
1042 ret = -EAGAIN;
1043
1044 module_put(t->me);
1045 xt_table_unlock(t);
1046 } else
1047 ret = PTR_ERR(t);
1048
1049 return ret;
1050 }
1051
1052 static int
1053 __do_replace(struct net *net, const char *name, unsigned int valid_hooks,
1054 struct xt_table_info *newinfo, unsigned int num_counters,
1055 void __user *counters_ptr)
1056 {
1057 int ret;
1058 struct xt_table *t;
1059 struct xt_table_info *oldinfo;
1060 struct xt_counters *counters;
1061 struct ip6t_entry *iter;
1062
1063 counters = xt_counters_alloc(num_counters);
1064 if (!counters) {
1065 ret = -ENOMEM;
1066 goto out;
1067 }
1068
1069 t = xt_request_find_table_lock(net, AF_INET6, name);
1070 if (IS_ERR(t)) {
1071 ret = PTR_ERR(t);
1072 goto free_newinfo_counters_untrans;
1073 }
1074
1075 /* You lied! */
1076 if (valid_hooks != t->valid_hooks) {
1077 ret = -EINVAL;
1078 goto put_module;
1079 }
1080
1081 oldinfo = xt_replace_table(t, num_counters, newinfo, &ret);
1082 if (!oldinfo)
1083 goto put_module;
1084
1085 /* Update module usage count based on number of rules */
1086 if ((oldinfo->number > oldinfo->initial_entries) ||
1087 (newinfo->number <= oldinfo->initial_entries))
1088 module_put(t->me);
1089 if ((oldinfo->number > oldinfo->initial_entries) &&
1090 (newinfo->number <= oldinfo->initial_entries))
1091 module_put(t->me);
1092
1093 xt_table_unlock(t);
1094
1095 get_old_counters(oldinfo, counters);
1096
1097 /* Decrease module usage counts and free resource */
1098 xt_entry_foreach(iter, oldinfo->entries, oldinfo->size)
1099 cleanup_entry(iter, net);
1100
1101 xt_free_table_info(oldinfo);
1102 if (copy_to_user(counters_ptr, counters,
1103 sizeof(struct xt_counters) * num_counters) != 0) {
1104 /* Silent error, can't fail, new table is already in place */
1105 net_warn_ratelimited("ip6tables: counters copy to user failed while replacing table\n");
1106 }
1107 vfree(counters);
1108 return 0;
1109
1110 put_module:
1111 module_put(t->me);
1112 xt_table_unlock(t);
1113 free_newinfo_counters_untrans:
1114 vfree(counters);
1115 out:
1116 return ret;
1117 }
1118
1119 static int
1120 do_replace(struct net *net, sockptr_t arg, unsigned int len)
1121 {
1122 int ret;
1123 struct ip6t_replace tmp;
1124 struct xt_table_info *newinfo;
1125 void *loc_cpu_entry;
1126 struct ip6t_entry *iter;
1127
1128 if (len < sizeof(tmp))
1129 return -EINVAL;
1130 if (copy_from_sockptr(&tmp, arg, sizeof(tmp)) != 0)
1131 return -EFAULT;
1132
1133 /* overflow check */
1134 if (tmp.num_counters >= INT_MAX / sizeof(struct xt_counters))
1135 return -ENOMEM;
1136 if (tmp.num_counters == 0)
1137 return -EINVAL;
1138 if ((u64)len < (u64)tmp.size + sizeof(tmp))
1139 return -EINVAL;
1140
1141 tmp.name[sizeof(tmp.name)-1] = 0;
1142
1143 newinfo = xt_alloc_table_info(tmp.size);
1144 if (!newinfo)
1145 return -ENOMEM;
1146
1147 loc_cpu_entry = newinfo->entries;
1148 if (copy_from_sockptr_offset(loc_cpu_entry, arg, sizeof(tmp),
1149 tmp.size) != 0) {
1150 ret = -EFAULT;
1151 goto free_newinfo;
1152 }
1153
1154 ret = translate_table(net, newinfo, loc_cpu_entry, &tmp);
1155 if (ret != 0)
1156 goto free_newinfo;
1157
1158 ret = __do_replace(net, tmp.name, tmp.valid_hooks, newinfo,
1159 tmp.num_counters, tmp.counters);
1160 if (ret)
1161 goto free_newinfo_untrans;
1162 return 0;
1163
1164 free_newinfo_untrans:
1165 xt_entry_foreach(iter, loc_cpu_entry, newinfo->size)
1166 cleanup_entry(iter, net);
1167 free_newinfo:
1168 xt_free_table_info(newinfo);
1169 return ret;
1170 }
1171
1172 static int
1173 do_add_counters(struct net *net, sockptr_t arg, unsigned int len)
1174 {
1175 unsigned int i;
1176 struct xt_counters_info tmp;
1177 struct xt_counters *paddc;
1178 struct xt_table *t;
1179 const struct xt_table_info *private;
1180 int ret = 0;
1181 struct ip6t_entry *iter;
1182 unsigned int addend;
1183
1184 paddc = xt_copy_counters(arg, len, &tmp);
1185 if (IS_ERR(paddc))
1186 return PTR_ERR(paddc);
1187 t = xt_find_table_lock(net, AF_INET6, tmp.name);
1188 if (IS_ERR(t)) {
1189 ret = PTR_ERR(t);
1190 goto free;
1191 }
1192
1193 local_bh_disable();
1194 private = t->private;
1195 if (private->number != tmp.num_counters) {
1196 ret = -EINVAL;
1197 goto unlock_up_free;
1198 }
1199
1200 i = 0;
1201 addend = xt_write_recseq_begin();
1202 xt_entry_foreach(iter, private->entries, private->size) {
1203 struct xt_counters *tmp;
1204
1205 tmp = xt_get_this_cpu_counter(&iter->counters);
1206 ADD_COUNTER(*tmp, paddc[i].bcnt, paddc[i].pcnt);
1207 ++i;
1208 }
1209 xt_write_recseq_end(addend);
1210 unlock_up_free:
1211 local_bh_enable();
1212 xt_table_unlock(t);
1213 module_put(t->me);
1214 free:
1215 vfree(paddc);
1216
1217 return ret;
1218 }
1219
1220 #ifdef CONFIG_NETFILTER_XTABLES_COMPAT
1221 struct compat_ip6t_replace {
1222 char name[XT_TABLE_MAXNAMELEN];
1223 u32 valid_hooks;
1224 u32 num_entries;
1225 u32 size;
1226 u32 hook_entry[NF_INET_NUMHOOKS];
1227 u32 underflow[NF_INET_NUMHOOKS];
1228 u32 num_counters;
1229 compat_uptr_t counters; /* struct xt_counters * */
1230 struct compat_ip6t_entry entries[];
1231 };
1232
1233 static int
1234 compat_copy_entry_to_user(struct ip6t_entry *e, void __user **dstptr,
1235 unsigned int *size, struct xt_counters *counters,
1236 unsigned int i)
1237 {
1238 struct xt_entry_target *t;
1239 struct compat_ip6t_entry __user *ce;
1240 u_int16_t target_offset, next_offset;
1241 compat_uint_t origsize;
1242 const struct xt_entry_match *ematch;
1243 int ret = 0;
1244
1245 origsize = *size;
1246 ce = *dstptr;
1247 if (copy_to_user(ce, e, sizeof(struct ip6t_entry)) != 0 ||
1248 copy_to_user(&ce->counters, &counters[i],
1249 sizeof(counters[i])) != 0)
1250 return -EFAULT;
1251
1252 *dstptr += sizeof(struct compat_ip6t_entry);
1253 *size -= sizeof(struct ip6t_entry) - sizeof(struct compat_ip6t_entry);
1254
1255 xt_ematch_foreach(ematch, e) {
1256 ret = xt_compat_match_to_user(ematch, dstptr, size);
1257 if (ret != 0)
1258 return ret;
1259 }
1260 target_offset = e->target_offset - (origsize - *size);
1261 t = ip6t_get_target(e);
1262 ret = xt_compat_target_to_user(t, dstptr, size);
1263 if (ret)
1264 return ret;
1265 next_offset = e->next_offset - (origsize - *size);
1266 if (put_user(target_offset, &ce->target_offset) != 0 ||
1267 put_user(next_offset, &ce->next_offset) != 0)
1268 return -EFAULT;
1269 return 0;
1270 }
1271
1272 static int
1273 compat_find_calc_match(struct xt_entry_match *m,
1274 const struct ip6t_ip6 *ipv6,
1275 int *size)
1276 {
1277 struct xt_match *match;
1278
1279 match = xt_request_find_match(NFPROTO_IPV6, m->u.user.name,
1280 m->u.user.revision);
1281 if (IS_ERR(match))
1282 return PTR_ERR(match);
1283
1284 m->u.kernel.match = match;
1285 *size += xt_compat_match_offset(match);
1286 return 0;
1287 }
1288
1289 static void compat_release_entry(struct compat_ip6t_entry *e)
1290 {
1291 struct xt_entry_target *t;
1292 struct xt_entry_match *ematch;
1293
1294 /* Cleanup all matches */
1295 xt_ematch_foreach(ematch, e)
1296 module_put(ematch->u.kernel.match->me);
1297 t = compat_ip6t_get_target(e);
1298 module_put(t->u.kernel.target->me);
1299 }
1300
1301 static int
1302 check_compat_entry_size_and_hooks(struct compat_ip6t_entry *e,
1303 struct xt_table_info *newinfo,
1304 unsigned int *size,
1305 const unsigned char *base,
1306 const unsigned char *limit)
1307 {
1308 struct xt_entry_match *ematch;
1309 struct xt_entry_target *t;
1310 struct xt_target *target;
1311 unsigned int entry_offset;
1312 unsigned int j;
1313 int ret, off;
1314
1315 if ((unsigned long)e % __alignof__(struct compat_ip6t_entry) != 0 ||
1316 (unsigned char *)e + sizeof(struct compat_ip6t_entry) >= limit ||
1317 (unsigned char *)e + e->next_offset > limit)
1318 return -EINVAL;
1319
1320 if (e->next_offset < sizeof(struct compat_ip6t_entry) +
1321 sizeof(struct compat_xt_entry_target))
1322 return -EINVAL;
1323
1324 if (!ip6_checkentry(&e->ipv6))
1325 return -EINVAL;
1326
1327 ret = xt_compat_check_entry_offsets(e, e->elems,
1328 e->target_offset, e->next_offset);
1329 if (ret)
1330 return ret;
1331
1332 off = sizeof(struct ip6t_entry) - sizeof(struct compat_ip6t_entry);
1333 entry_offset = (void *)e - (void *)base;
1334 j = 0;
1335 xt_ematch_foreach(ematch, e) {
1336 ret = compat_find_calc_match(ematch, &e->ipv6, &off);
1337 if (ret != 0)
1338 goto release_matches;
1339 ++j;
1340 }
1341
1342 t = compat_ip6t_get_target(e);
1343 target = xt_request_find_target(NFPROTO_IPV6, t->u.user.name,
1344 t->u.user.revision);
1345 if (IS_ERR(target)) {
1346 ret = PTR_ERR(target);
1347 goto release_matches;
1348 }
1349 t->u.kernel.target = target;
1350
1351 off += xt_compat_target_offset(target);
1352 *size += off;
1353 ret = xt_compat_add_offset(AF_INET6, entry_offset, off);
1354 if (ret)
1355 goto out;
1356
1357 return 0;
1358
1359 out:
1360 module_put(t->u.kernel.target->me);
1361 release_matches:
1362 xt_ematch_foreach(ematch, e) {
1363 if (j-- == 0)
1364 break;
1365 module_put(ematch->u.kernel.match->me);
1366 }
1367 return ret;
1368 }
1369
1370 static void
1371 compat_copy_entry_from_user(struct compat_ip6t_entry *e, void **dstptr,
1372 unsigned int *size,
1373 struct xt_table_info *newinfo, unsigned char *base)
1374 {
1375 struct xt_entry_target *t;
1376 struct ip6t_entry *de;
1377 unsigned int origsize;
1378 int h;
1379 struct xt_entry_match *ematch;
1380
1381 origsize = *size;
1382 de = *dstptr;
1383 memcpy(de, e, sizeof(struct ip6t_entry));
1384 memcpy(&de->counters, &e->counters, sizeof(e->counters));
1385
1386 *dstptr += sizeof(struct ip6t_entry);
1387 *size += sizeof(struct ip6t_entry) - sizeof(struct compat_ip6t_entry);
1388
1389 xt_ematch_foreach(ematch, e)
1390 xt_compat_match_from_user(ematch, dstptr, size);
1391
1392 de->target_offset = e->target_offset - (origsize - *size);
1393 t = compat_ip6t_get_target(e);
1394 xt_compat_target_from_user(t, dstptr, size);
1395
1396 de->next_offset = e->next_offset - (origsize - *size);
1397 for (h = 0; h < NF_INET_NUMHOOKS; h++) {
1398 if ((unsigned char *)de - base < newinfo->hook_entry[h])
1399 newinfo->hook_entry[h] -= origsize - *size;
1400 if ((unsigned char *)de - base < newinfo->underflow[h])
1401 newinfo->underflow[h] -= origsize - *size;
1402 }
1403 }
1404
1405 static int
1406 translate_compat_table(struct net *net,
1407 struct xt_table_info **pinfo,
1408 void **pentry0,
1409 const struct compat_ip6t_replace *compatr)
1410 {
1411 unsigned int i, j;
1412 struct xt_table_info *newinfo, *info;
1413 void *pos, *entry0, *entry1;
1414 struct compat_ip6t_entry *iter0;
1415 struct ip6t_replace repl;
1416 unsigned int size;
1417 int ret;
1418
1419 info = *pinfo;
1420 entry0 = *pentry0;
1421 size = compatr->size;
1422 info->number = compatr->num_entries;
1423
1424 j = 0;
1425 xt_compat_lock(AF_INET6);
1426 ret = xt_compat_init_offsets(AF_INET6, compatr->num_entries);
1427 if (ret)
1428 goto out_unlock;
1429 /* Walk through entries, checking offsets. */
1430 xt_entry_foreach(iter0, entry0, compatr->size) {
1431 ret = check_compat_entry_size_and_hooks(iter0, info, &size,
1432 entry0,
1433 entry0 + compatr->size);
1434 if (ret != 0)
1435 goto out_unlock;
1436 ++j;
1437 }
1438
1439 ret = -EINVAL;
1440 if (j != compatr->num_entries)
1441 goto out_unlock;
1442
1443 ret = -ENOMEM;
1444 newinfo = xt_alloc_table_info(size);
1445 if (!newinfo)
1446 goto out_unlock;
1447
1448 memset(newinfo->entries, 0, size);
1449
1450 newinfo->number = compatr->num_entries;
1451 for (i = 0; i < NF_INET_NUMHOOKS; i++) {
1452 newinfo->hook_entry[i] = compatr->hook_entry[i];
1453 newinfo->underflow[i] = compatr->underflow[i];
1454 }
1455 entry1 = newinfo->entries;
1456 pos = entry1;
1457 size = compatr->size;
1458 xt_entry_foreach(iter0, entry0, compatr->size)
1459 compat_copy_entry_from_user(iter0, &pos, &size,
1460 newinfo, entry1);
1461
1462 /* all module references in entry0 are now gone. */
1463 xt_compat_flush_offsets(AF_INET6);
1464 xt_compat_unlock(AF_INET6);
1465
1466 memcpy(&repl, compatr, sizeof(*compatr));
1467
1468 for (i = 0; i < NF_INET_NUMHOOKS; i++) {
1469 repl.hook_entry[i] = newinfo->hook_entry[i];
1470 repl.underflow[i] = newinfo->underflow[i];
1471 }
1472
1473 repl.num_counters = 0;
1474 repl.counters = NULL;
1475 repl.size = newinfo->size;
1476 ret = translate_table(net, newinfo, entry1, &repl);
1477 if (ret)
1478 goto free_newinfo;
1479
1480 *pinfo = newinfo;
1481 *pentry0 = entry1;
1482 xt_free_table_info(info);
1483 return 0;
1484
1485 free_newinfo:
1486 xt_free_table_info(newinfo);
1487 return ret;
1488 out_unlock:
1489 xt_compat_flush_offsets(AF_INET6);
1490 xt_compat_unlock(AF_INET6);
1491 xt_entry_foreach(iter0, entry0, compatr->size) {
1492 if (j-- == 0)
1493 break;
1494 compat_release_entry(iter0);
1495 }
1496 return ret;
1497 }
1498
1499 static int
1500 compat_do_replace(struct net *net, sockptr_t arg, unsigned int len)
1501 {
1502 int ret;
1503 struct compat_ip6t_replace tmp;
1504 struct xt_table_info *newinfo;
1505 void *loc_cpu_entry;
1506 struct ip6t_entry *iter;
1507
1508 if (len < sizeof(tmp))
1509 return -EINVAL;
1510 if (copy_from_sockptr(&tmp, arg, sizeof(tmp)) != 0)
1511 return -EFAULT;
1512
1513 /* overflow check */
1514 if (tmp.num_counters >= INT_MAX / sizeof(struct xt_counters))
1515 return -ENOMEM;
1516 if (tmp.num_counters == 0)
1517 return -EINVAL;
1518 if ((u64)len < (u64)tmp.size + sizeof(tmp))
1519 return -EINVAL;
1520
1521 tmp.name[sizeof(tmp.name)-1] = 0;
1522
1523 newinfo = xt_alloc_table_info(tmp.size);
1524 if (!newinfo)
1525 return -ENOMEM;
1526
1527 loc_cpu_entry = newinfo->entries;
1528 if (copy_from_sockptr_offset(loc_cpu_entry, arg, sizeof(tmp),
1529 tmp.size) != 0) {
1530 ret = -EFAULT;
1531 goto free_newinfo;
1532 }
1533
1534 ret = translate_compat_table(net, &newinfo, &loc_cpu_entry, &tmp);
1535 if (ret != 0)
1536 goto free_newinfo;
1537
1538 ret = __do_replace(net, tmp.name, tmp.valid_hooks, newinfo,
1539 tmp.num_counters, compat_ptr(tmp.counters));
1540 if (ret)
1541 goto free_newinfo_untrans;
1542 return 0;
1543
1544 free_newinfo_untrans:
1545 xt_entry_foreach(iter, loc_cpu_entry, newinfo->size)
1546 cleanup_entry(iter, net);
1547 free_newinfo:
1548 xt_free_table_info(newinfo);
1549 return ret;
1550 }
1551
1552 struct compat_ip6t_get_entries {
1553 char name[XT_TABLE_MAXNAMELEN];
1554 compat_uint_t size;
1555 struct compat_ip6t_entry entrytable[];
1556 };
1557
1558 static int
1559 compat_copy_entries_to_user(unsigned int total_size, struct xt_table *table,
1560 void __user *userptr)
1561 {
1562 struct xt_counters *counters;
1563 const struct xt_table_info *private = table->private;
1564 void __user *pos;
1565 unsigned int size;
1566 int ret = 0;
1567 unsigned int i = 0;
1568 struct ip6t_entry *iter;
1569
1570 counters = alloc_counters(table);
1571 if (IS_ERR(counters))
1572 return PTR_ERR(counters);
1573
1574 pos = userptr;
1575 size = total_size;
1576 xt_entry_foreach(iter, private->entries, total_size) {
1577 ret = compat_copy_entry_to_user(iter, &pos,
1578 &size, counters, i++);
1579 if (ret != 0)
1580 break;
1581 }
1582
1583 vfree(counters);
1584 return ret;
1585 }
1586
1587 static int
1588 compat_get_entries(struct net *net, struct compat_ip6t_get_entries __user *uptr,
1589 int *len)
1590 {
1591 int ret;
1592 struct compat_ip6t_get_entries get;
1593 struct xt_table *t;
1594
1595 if (*len < sizeof(get))
1596 return -EINVAL;
1597
1598 if (copy_from_user(&get, uptr, sizeof(get)) != 0)
1599 return -EFAULT;
1600
1601 if (*len != sizeof(struct compat_ip6t_get_entries) + get.size)
1602 return -EINVAL;
1603
1604 get.name[sizeof(get.name) - 1] = '\0';
1605
1606 xt_compat_lock(AF_INET6);
1607 t = xt_find_table_lock(net, AF_INET6, get.name);
1608 if (!IS_ERR(t)) {
1609 const struct xt_table_info *private = t->private;
1610 struct xt_table_info info;
1611 ret = compat_table_info(private, &info);
1612 if (!ret && get.size == info.size)
1613 ret = compat_copy_entries_to_user(private->size,
1614 t, uptr->entrytable);
1615 else if (!ret)
1616 ret = -EAGAIN;
1617
1618 xt_compat_flush_offsets(AF_INET6);
1619 module_put(t->me);
1620 xt_table_unlock(t);
1621 } else
1622 ret = PTR_ERR(t);
1623
1624 xt_compat_unlock(AF_INET6);
1625 return ret;
1626 }
1627 #endif
1628
1629 static int
1630 do_ip6t_set_ctl(struct sock *sk, int cmd, sockptr_t arg, unsigned int len)
1631 {
1632 int ret;
1633
1634 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
1635 return -EPERM;
1636
1637 switch (cmd) {
1638 case IP6T_SO_SET_REPLACE:
1639 #ifdef CONFIG_NETFILTER_XTABLES_COMPAT
1640 if (in_compat_syscall())
1641 ret = compat_do_replace(sock_net(sk), arg, len);
1642 else
1643 #endif
1644 ret = do_replace(sock_net(sk), arg, len);
1645 break;
1646
1647 case IP6T_SO_SET_ADD_COUNTERS:
1648 ret = do_add_counters(sock_net(sk), arg, len);
1649 break;
1650
1651 default:
1652 ret = -EINVAL;
1653 }
1654
1655 return ret;
1656 }
1657
1658 static int
1659 do_ip6t_get_ctl(struct sock *sk, int cmd, void __user *user, int *len)
1660 {
1661 int ret;
1662
1663 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
1664 return -EPERM;
1665
1666 switch (cmd) {
1667 case IP6T_SO_GET_INFO:
1668 ret = get_info(sock_net(sk), user, len);
1669 break;
1670
1671 case IP6T_SO_GET_ENTRIES:
1672 #ifdef CONFIG_NETFILTER_XTABLES_COMPAT
1673 if (in_compat_syscall())
1674 ret = compat_get_entries(sock_net(sk), user, len);
1675 else
1676 #endif
1677 ret = get_entries(sock_net(sk), user, len);
1678 break;
1679
1680 case IP6T_SO_GET_REVISION_MATCH:
1681 case IP6T_SO_GET_REVISION_TARGET: {
1682 struct xt_get_revision rev;
1683 int target;
1684
1685 if (*len != sizeof(rev)) {
1686 ret = -EINVAL;
1687 break;
1688 }
1689 if (copy_from_user(&rev, user, sizeof(rev)) != 0) {
1690 ret = -EFAULT;
1691 break;
1692 }
1693 rev.name[sizeof(rev.name)-1] = 0;
1694
1695 if (cmd == IP6T_SO_GET_REVISION_TARGET)
1696 target = 1;
1697 else
1698 target = 0;
1699
1700 try_then_request_module(xt_find_revision(AF_INET6, rev.name,
1701 rev.revision,
1702 target, &ret),
1703 "ip6t_%s", rev.name);
1704 break;
1705 }
1706
1707 default:
1708 ret = -EINVAL;
1709 }
1710
1711 return ret;
1712 }
1713
1714 static void __ip6t_unregister_table(struct net *net, struct xt_table *table)
1715 {
1716 struct xt_table_info *private;
1717 void *loc_cpu_entry;
1718 struct module *table_owner = table->me;
1719 struct ip6t_entry *iter;
1720
1721 private = xt_unregister_table(table);
1722
1723 /* Decrease module usage counts and free resources */
1724 loc_cpu_entry = private->entries;
1725 xt_entry_foreach(iter, loc_cpu_entry, private->size)
1726 cleanup_entry(iter, net);
1727 if (private->number > private->initial_entries)
1728 module_put(table_owner);
1729 xt_free_table_info(private);
1730 }
1731
1732 int ip6t_register_table(struct net *net, const struct xt_table *table,
1733 const struct ip6t_replace *repl,
1734 const struct nf_hook_ops *template_ops)
1735 {
1736 struct nf_hook_ops *ops;
1737 unsigned int num_ops;
1738 int ret, i;
1739 struct xt_table_info *newinfo;
1740 struct xt_table_info bootstrap = {0};
1741 void *loc_cpu_entry;
1742 struct xt_table *new_table;
1743
1744 newinfo = xt_alloc_table_info(repl->size);
1745 if (!newinfo)
1746 return -ENOMEM;
1747
1748 loc_cpu_entry = newinfo->entries;
1749 memcpy(loc_cpu_entry, repl->entries, repl->size);
1750
1751 ret = translate_table(net, newinfo, loc_cpu_entry, repl);
1752 if (ret != 0) {
1753 xt_free_table_info(newinfo);
1754 return ret;
1755 }
1756
1757 new_table = xt_register_table(net, table, &bootstrap, newinfo);
1758 if (IS_ERR(new_table)) {
1759 struct ip6t_entry *iter;
1760
1761 xt_entry_foreach(iter, loc_cpu_entry, newinfo->size)
1762 cleanup_entry(iter, net);
1763 xt_free_table_info(newinfo);
1764 return PTR_ERR(new_table);
1765 }
1766
1767 if (!template_ops)
1768 return 0;
1769
1770 num_ops = hweight32(table->valid_hooks);
1771 if (num_ops == 0) {
1772 ret = -EINVAL;
1773 goto out_free;
1774 }
1775
1776 ops = kmemdup_array(template_ops, num_ops, sizeof(*ops), GFP_KERNEL);
1777 if (!ops) {
1778 ret = -ENOMEM;
1779 goto out_free;
1780 }
1781
1782 for (i = 0; i < num_ops; i++)
1783 ops[i].priv = new_table;
1784
1785 new_table->ops = ops;
1786
1787 ret = nf_register_net_hooks(net, ops, num_ops);
1788 if (ret != 0)
1789 goto out_free;
1790
1791 return ret;
1792
1793 out_free:
1794 __ip6t_unregister_table(net, new_table);
1795 return ret;
1796 }
1797
1798 void ip6t_unregister_table_pre_exit(struct net *net, const char *name)
1799 {
1800 struct xt_table *table = xt_find_table(net, NFPROTO_IPV6, name);
1801
1802 if (table)
1803 nf_unregister_net_hooks(net, table->ops, hweight32(table->valid_hooks));
1804 }
1805
1806 void ip6t_unregister_table_exit(struct net *net, const char *name)
1807 {
1808 struct xt_table *table = xt_find_table(net, NFPROTO_IPV6, name);
1809
1810 if (table)
1811 __ip6t_unregister_table(net, table);
1812 }
1813
1814 /* The built-in targets: standard (NULL) and error. */
1815 static struct xt_target ip6t_builtin_tg[] __read_mostly = {
1816 {
1817 .name = XT_STANDARD_TARGET,
1818 .targetsize = sizeof(int),
1819 .family = NFPROTO_IPV6,
1820 #ifdef CONFIG_NETFILTER_XTABLES_COMPAT
1821 .compatsize = sizeof(compat_int_t),
1822 .compat_from_user = compat_standard_from_user,
1823 .compat_to_user = compat_standard_to_user,
1824 #endif
1825 },
1826 {
1827 .name = XT_ERROR_TARGET,
1828 .target = ip6t_error,
1829 .targetsize = XT_FUNCTION_MAXNAMELEN,
1830 .family = NFPROTO_IPV6,
1831 },
1832 };
1833
1834 static struct nf_sockopt_ops ip6t_sockopts = {
1835 .pf = PF_INET6,
1836 .set_optmin = IP6T_BASE_CTL,
1837 .set_optmax = IP6T_SO_SET_MAX+1,
1838 .set = do_ip6t_set_ctl,
1839 .get_optmin = IP6T_BASE_CTL,
1840 .get_optmax = IP6T_SO_GET_MAX+1,
1841 .get = do_ip6t_get_ctl,
1842 .owner = THIS_MODULE,
1843 };
1844
1845 static int __net_init ip6_tables_net_init(struct net *net)
1846 {
1847 return xt_proto_init(net, NFPROTO_IPV6);
1848 }
1849
1850 static void __net_exit ip6_tables_net_exit(struct net *net)
1851 {
1852 xt_proto_fini(net, NFPROTO_IPV6);
1853 }
1854
1855 static struct pernet_operations ip6_tables_net_ops = {
1856 .init = ip6_tables_net_init,
1857 .exit = ip6_tables_net_exit,
1858 };
1859
1860 static int __init ip6_tables_init(void)
1861 {
1862 int ret;
1863
1864 ret = register_pernet_subsys(&ip6_tables_net_ops);
1865 if (ret < 0)
1866 goto err1;
1867
1868 /* No one else will be downing sem now, so we won't sleep */
1869 ret = xt_register_targets(ip6t_builtin_tg, ARRAY_SIZE(ip6t_builtin_tg));
1870 if (ret < 0)
1871 goto err2;
1872
1873 /* Register setsockopt */
1874 ret = nf_register_sockopt(&ip6t_sockopts);
1875 if (ret < 0)
1876 goto err4;
1877
1878 return 0;
1879
1880 err4:
1881 xt_unregister_targets(ip6t_builtin_tg, ARRAY_SIZE(ip6t_builtin_tg));
1882 err2:
1883 unregister_pernet_subsys(&ip6_tables_net_ops);
1884 err1:
1885 return ret;
1886 }
1887
1888 static void __exit ip6_tables_fini(void)
1889 {
1890 nf_unregister_sockopt(&ip6t_sockopts);
1891
1892 xt_unregister_targets(ip6t_builtin_tg, ARRAY_SIZE(ip6t_builtin_tg));
1893 unregister_pernet_subsys(&ip6_tables_net_ops);
1894 }
1895
1896 EXPORT_SYMBOL(ip6t_register_table);
1897 EXPORT_SYMBOL(ip6t_unregister_table_pre_exit);
1898 EXPORT_SYMBOL(ip6t_unregister_table_exit);
1899 EXPORT_SYMBOL(ip6t_do_table);
1900
1901 module_init(ip6_tables_init);
1902 module_exit(ip6_tables_fini);
Linux Kernel