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12#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
13#include <linux/cache.h>
14#include <linux/capability.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/icmp.h>
21#include <net/ip.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/x_tables.h>
30#include <linux/netfilter_ipv4/ip_tables.h>
31#include <net/netfilter/nf_log.h>
32#include "../../netfilter/xt_repldata.h"
33
34MODULE_LICENSE("GPL");
35MODULE_AUTHOR("Netfilter Core Team <coreteam@netfilter.org>");
36MODULE_DESCRIPTION("IPv4 packet filter");
37
38void *ipt_alloc_initial_table(const struct xt_table *info)
39{
40 return xt_alloc_initial_table(ipt, IPT);
41}
42EXPORT_SYMBOL_GPL(ipt_alloc_initial_table);
43
44
45
46static inline bool
47ip_packet_match(const struct iphdr *ip,
48 const char *indev,
49 const char *outdev,
50 const struct ipt_ip *ipinfo,
51 int isfrag)
52{
53 unsigned long ret;
54
55 if (NF_INVF(ipinfo, IPT_INV_SRCIP,
56 (ip->saddr & ipinfo->smsk.s_addr) != ipinfo->src.s_addr) ||
57 NF_INVF(ipinfo, IPT_INV_DSTIP,
58 (ip->daddr & ipinfo->dmsk.s_addr) != ipinfo->dst.s_addr))
59 return false;
60
61 ret = ifname_compare_aligned(indev, ipinfo->iniface, ipinfo->iniface_mask);
62
63 if (NF_INVF(ipinfo, IPT_INV_VIA_IN, ret != 0))
64 return false;
65
66 ret = ifname_compare_aligned(outdev, ipinfo->outiface, ipinfo->outiface_mask);
67
68 if (NF_INVF(ipinfo, IPT_INV_VIA_OUT, ret != 0))
69 return false;
70
71
72 if (ipinfo->proto &&
73 NF_INVF(ipinfo, IPT_INV_PROTO, ip->protocol != ipinfo->proto))
74 return false;
75
76
77
78 if (NF_INVF(ipinfo, IPT_INV_FRAG,
79 (ipinfo->flags & IPT_F_FRAG) && !isfrag))
80 return false;
81
82 return true;
83}
84
85static bool
86ip_checkentry(const struct ipt_ip *ip)
87{
88 if (ip->flags & ~IPT_F_MASK)
89 return false;
90 if (ip->invflags & ~IPT_INV_MASK)
91 return false;
92 return true;
93}
94
95static unsigned int
96ipt_error(struct sk_buff *skb, const struct xt_action_param *par)
97{
98 net_info_ratelimited("error: `%s'\n", (const char *)par->targinfo);
99
100 return NF_DROP;
101}
102
103
104static inline struct ipt_entry *
105get_entry(const void *base, unsigned int offset)
106{
107 return (struct ipt_entry *)(base + offset);
108}
109
110
111
112static inline bool unconditional(const struct ipt_entry *e)
113{
114 static const struct ipt_ip uncond;
115
116 return e->target_offset == sizeof(struct ipt_entry) &&
117 memcmp(&e->ip, &uncond, sizeof(uncond)) == 0;
118}
119
120
121static inline const struct xt_entry_target *
122ipt_get_target_c(const struct ipt_entry *e)
123{
124 return ipt_get_target((struct ipt_entry *)e);
125}
126
127#if IS_ENABLED(CONFIG_NETFILTER_XT_TARGET_TRACE)
128static const char *const hooknames[] = {
129 [NF_INET_PRE_ROUTING] = "PREROUTING",
130 [NF_INET_LOCAL_IN] = "INPUT",
131 [NF_INET_FORWARD] = "FORWARD",
132 [NF_INET_LOCAL_OUT] = "OUTPUT",
133 [NF_INET_POST_ROUTING] = "POSTROUTING",
134};
135
136enum nf_ip_trace_comments {
137 NF_IP_TRACE_COMMENT_RULE,
138 NF_IP_TRACE_COMMENT_RETURN,
139 NF_IP_TRACE_COMMENT_POLICY,
140};
141
142static const char *const comments[] = {
143 [NF_IP_TRACE_COMMENT_RULE] = "rule",
144 [NF_IP_TRACE_COMMENT_RETURN] = "return",
145 [NF_IP_TRACE_COMMENT_POLICY] = "policy",
146};
147
148static const struct nf_loginfo trace_loginfo = {
149 .type = NF_LOG_TYPE_LOG,
150 .u = {
151 .log = {
152 .level = 4,
153 .logflags = NF_LOG_DEFAULT_MASK,
154 },
155 },
156};
157
158
159static inline int
160get_chainname_rulenum(const struct ipt_entry *s, const struct ipt_entry *e,
161 const char *hookname, const char **chainname,
162 const char **comment, unsigned int *rulenum)
163{
164 const struct xt_standard_target *t = (void *)ipt_get_target_c(s);
165
166 if (strcmp(t->target.u.kernel.target->name, XT_ERROR_TARGET) == 0) {
167
168 *chainname = t->target.data;
169 (*rulenum) = 0;
170 } else if (s == e) {
171 (*rulenum)++;
172
173 if (unconditional(s) &&
174 strcmp(t->target.u.kernel.target->name,
175 XT_STANDARD_TARGET) == 0 &&
176 t->verdict < 0) {
177
178 *comment = *chainname == hookname
179 ? comments[NF_IP_TRACE_COMMENT_POLICY]
180 : comments[NF_IP_TRACE_COMMENT_RETURN];
181 }
182 return 1;
183 } else
184 (*rulenum)++;
185
186 return 0;
187}
188
189static void trace_packet(struct net *net,
190 const struct sk_buff *skb,
191 unsigned int hook,
192 const struct net_device *in,
193 const struct net_device *out,
194 const char *tablename,
195 const struct xt_table_info *private,
196 const struct ipt_entry *e)
197{
198 const struct ipt_entry *root;
199 const char *hookname, *chainname, *comment;
200 const struct ipt_entry *iter;
201 unsigned int rulenum = 0;
202
203 root = get_entry(private->entries, private->hook_entry[hook]);
204
205 hookname = chainname = hooknames[hook];
206 comment = comments[NF_IP_TRACE_COMMENT_RULE];
207
208 xt_entry_foreach(iter, root, private->size - private->hook_entry[hook])
209 if (get_chainname_rulenum(iter, e, hookname,
210 &chainname, &comment, &rulenum) != 0)
211 break;
212
213 nf_log_trace(net, AF_INET, hook, skb, in, out, &trace_loginfo,
214 "TRACE: %s:%s:%s:%u ",
215 tablename, chainname, comment, rulenum);
216}
217#endif
218
219static inline
220struct ipt_entry *ipt_next_entry(const struct ipt_entry *entry)
221{
222 return (void *)entry + entry->next_offset;
223}
224
225
226unsigned int
227ipt_do_table(struct sk_buff *skb,
228 const struct nf_hook_state *state,
229 struct xt_table *table)
230{
231 unsigned int hook = state->hook;
232 static const char nulldevname[IFNAMSIZ] __attribute__((aligned(sizeof(long))));
233 const struct iphdr *ip;
234
235 unsigned int verdict = NF_DROP;
236 const char *indev, *outdev;
237 const void *table_base;
238 struct ipt_entry *e, **jumpstack;
239 unsigned int stackidx, cpu;
240 const struct xt_table_info *private;
241 struct xt_action_param acpar;
242 unsigned int addend;
243
244
245 stackidx = 0;
246 ip = ip_hdr(skb);
247 indev = state->in ? state->in->name : nulldevname;
248 outdev = state->out ? state->out->name : nulldevname;
249
250
251
252
253
254
255 acpar.fragoff = ntohs(ip->frag_off) & IP_OFFSET;
256 acpar.thoff = ip_hdrlen(skb);
257 acpar.hotdrop = false;
258 acpar.state = state;
259
260 WARN_ON(!(table->valid_hooks & (1 << hook)));
261 local_bh_disable();
262 addend = xt_write_recseq_begin();
263 private = table->private;
264 cpu = smp_processor_id();
265
266
267
268
269 smp_read_barrier_depends();
270 table_base = private->entries;
271 jumpstack = (struct ipt_entry **)private->jumpstack[cpu];
272
273
274
275
276
277
278
279
280 if (static_key_false(&xt_tee_enabled))
281 jumpstack += private->stacksize * __this_cpu_read(nf_skb_duplicated);
282
283 e = get_entry(table_base, private->hook_entry[hook]);
284
285 do {
286 const struct xt_entry_target *t;
287 const struct xt_entry_match *ematch;
288 struct xt_counters *counter;
289
290 WARN_ON(!e);
291 if (!ip_packet_match(ip, indev, outdev,
292 &e->ip, acpar.fragoff)) {
293 no_match:
294 e = ipt_next_entry(e);
295 continue;
296 }
297
298 xt_ematch_foreach(ematch, e) {
299 acpar.match = ematch->u.kernel.match;
300 acpar.matchinfo = ematch->data;
301 if (!acpar.match->match(skb, &acpar))
302 goto no_match;
303 }
304
305 counter = xt_get_this_cpu_counter(&e->counters);
306 ADD_COUNTER(*counter, skb->len, 1);
307
308 t = ipt_get_target(e);
309 WARN_ON(!t->u.kernel.target);
310
311#if IS_ENABLED(CONFIG_NETFILTER_XT_TARGET_TRACE)
312
313 if (unlikely(skb->nf_trace))
314 trace_packet(state->net, skb, hook, state->in,
315 state->out, table->name, private, e);
316#endif
317
318 if (!t->u.kernel.target->target) {
319 int v;
320
321 v = ((struct xt_standard_target *)t)->verdict;
322 if (v < 0) {
323
324 if (v != XT_RETURN) {
325 verdict = (unsigned int)(-v) - 1;
326 break;
327 }
328 if (stackidx == 0) {
329 e = get_entry(table_base,
330 private->underflow[hook]);
331 } else {
332 e = jumpstack[--stackidx];
333 e = ipt_next_entry(e);
334 }
335 continue;
336 }
337 if (table_base + v != ipt_next_entry(e) &&
338 !(e->ip.flags & IPT_F_GOTO))
339 jumpstack[stackidx++] = e;
340
341 e = get_entry(table_base, v);
342 continue;
343 }
344
345 acpar.target = t->u.kernel.target;
346 acpar.targinfo = t->data;
347
348 verdict = t->u.kernel.target->target(skb, &acpar);
349 if (verdict == XT_CONTINUE) {
350
351 ip = ip_hdr(skb);
352 e = ipt_next_entry(e);
353 } else {
354
355 break;
356 }
357 } while (!acpar.hotdrop);
358
359 xt_write_recseq_end(addend);
360 local_bh_enable();
361
362 if (acpar.hotdrop)
363 return NF_DROP;
364 else return verdict;
365}
366
367
368
369static int
370mark_source_chains(const struct xt_table_info *newinfo,
371 unsigned int valid_hooks, void *entry0,
372 unsigned int *offsets)
373{
374 unsigned int hook;
375
376
377
378 for (hook = 0; hook < NF_INET_NUMHOOKS; hook++) {
379 unsigned int pos = newinfo->hook_entry[hook];
380 struct ipt_entry *e = entry0 + pos;
381
382 if (!(valid_hooks & (1 << hook)))
383 continue;
384
385
386 e->counters.pcnt = pos;
387
388 for (;;) {
389 const struct xt_standard_target *t
390 = (void *)ipt_get_target_c(e);
391 int visited = e->comefrom & (1 << hook);
392
393 if (e->comefrom & (1 << NF_INET_NUMHOOKS))
394 return 0;
395
396 e->comefrom |= ((1 << hook) | (1 << NF_INET_NUMHOOKS));
397
398
399 if ((unconditional(e) &&
400 (strcmp(t->target.u.user.name,
401 XT_STANDARD_TARGET) == 0) &&
402 t->verdict < 0) || visited) {
403 unsigned int oldpos, size;
404
405 if ((strcmp(t->target.u.user.name,
406 XT_STANDARD_TARGET) == 0) &&
407 t->verdict < -NF_MAX_VERDICT - 1)
408 return 0;
409
410
411
412 do {
413 e->comefrom ^= (1<<NF_INET_NUMHOOKS);
414 oldpos = pos;
415 pos = e->counters.pcnt;
416 e->counters.pcnt = 0;
417
418
419 if (pos == oldpos)
420 goto next;
421
422 e = entry0 + pos;
423 } while (oldpos == pos + e->next_offset);
424
425
426 size = e->next_offset;
427 e = entry0 + pos + size;
428 if (pos + size >= newinfo->size)
429 return 0;
430 e->counters.pcnt = pos;
431 pos += size;
432 } else {
433 int newpos = t->verdict;
434
435 if (strcmp(t->target.u.user.name,
436 XT_STANDARD_TARGET) == 0 &&
437 newpos >= 0) {
438
439 if (!xt_find_jump_offset(offsets, newpos,
440 newinfo->number))
441 return 0;
442 e = entry0 + newpos;
443 } else {
444
445 newpos = pos + e->next_offset;
446 if (newpos >= newinfo->size)
447 return 0;
448 }
449 e = entry0 + newpos;
450 e->counters.pcnt = pos;
451 pos = newpos;
452 }
453 }
454next: ;
455 }
456 return 1;
457}
458
459static void cleanup_match(struct xt_entry_match *m, struct net *net)
460{
461 struct xt_mtdtor_param par;
462
463 par.net = net;
464 par.match = m->u.kernel.match;
465 par.matchinfo = m->data;
466 par.family = NFPROTO_IPV4;
467 if (par.match->destroy != NULL)
468 par.match->destroy(&par);
469 module_put(par.match->me);
470}
471
472static int
473check_match(struct xt_entry_match *m, struct xt_mtchk_param *par)
474{
475 const struct ipt_ip *ip = par->entryinfo;
476
477 par->match = m->u.kernel.match;
478 par->matchinfo = m->data;
479
480 return xt_check_match(par, m->u.match_size - sizeof(*m),
481 ip->proto, ip->invflags & IPT_INV_PROTO);
482}
483
484static int
485find_check_match(struct xt_entry_match *m, struct xt_mtchk_param *par)
486{
487 struct xt_match *match;
488 int ret;
489
490 match = xt_request_find_match(NFPROTO_IPV4, m->u.user.name,
491 m->u.user.revision);
492 if (IS_ERR(match))
493 return PTR_ERR(match);
494 m->u.kernel.match = match;
495
496 ret = check_match(m, par);
497 if (ret)
498 goto err;
499
500 return 0;
501err:
502 module_put(m->u.kernel.match->me);
503 return ret;
504}
505
506static int check_target(struct ipt_entry *e, struct net *net, const char *name)
507{
508 struct xt_entry_target *t = ipt_get_target(e);
509 struct xt_tgchk_param par = {
510 .net = net,
511 .table = name,
512 .entryinfo = e,
513 .target = t->u.kernel.target,
514 .targinfo = t->data,
515 .hook_mask = e->comefrom,
516 .family = NFPROTO_IPV4,
517 };
518
519 return xt_check_target(&par, t->u.target_size - sizeof(*t),
520 e->ip.proto, e->ip.invflags & IPT_INV_PROTO);
521}
522
523static int
524find_check_entry(struct ipt_entry *e, struct net *net, const char *name,
525 unsigned int size,
526 struct xt_percpu_counter_alloc_state *alloc_state)
527{
528 struct xt_entry_target *t;
529 struct xt_target *target;
530 int ret;
531 unsigned int j;
532 struct xt_mtchk_param mtpar;
533 struct xt_entry_match *ematch;
534
535 if (!xt_percpu_counter_alloc(alloc_state, &e->counters))
536 return -ENOMEM;
537
538 j = 0;
539 mtpar.net = net;
540 mtpar.table = name;
541 mtpar.entryinfo = &e->ip;
542 mtpar.hook_mask = e->comefrom;
543 mtpar.family = NFPROTO_IPV4;
544 xt_ematch_foreach(ematch, e) {
545 ret = find_check_match(ematch, &mtpar);
546 if (ret != 0)
547 goto cleanup_matches;
548 ++j;
549 }
550
551 t = ipt_get_target(e);
552 target = xt_request_find_target(NFPROTO_IPV4, t->u.user.name,
553 t->u.user.revision);
554 if (IS_ERR(target)) {
555 ret = PTR_ERR(target);
556 goto cleanup_matches;
557 }
558 t->u.kernel.target = target;
559
560 ret = check_target(e, net, name);
561 if (ret)
562 goto err;
563
564 return 0;
565 err:
566 module_put(t->u.kernel.target->me);
567 cleanup_matches:
568 xt_ematch_foreach(ematch, e) {
569 if (j-- == 0)
570 break;
571 cleanup_match(ematch, net);
572 }
573
574 xt_percpu_counter_free(&e->counters);
575
576 return ret;
577}
578
579static bool check_underflow(const struct ipt_entry *e)
580{
581 const struct xt_entry_target *t;
582 unsigned int verdict;
583
584 if (!unconditional(e))
585 return false;
586 t = ipt_get_target_c(e);
587 if (strcmp(t->u.user.name, XT_STANDARD_TARGET) != 0)
588 return false;
589 verdict = ((struct xt_standard_target *)t)->verdict;
590 verdict = -verdict - 1;
591 return verdict == NF_DROP || verdict == NF_ACCEPT;
592}
593
594static int
595check_entry_size_and_hooks(struct ipt_entry *e,
596 struct xt_table_info *newinfo,
597 const unsigned char *base,
598 const unsigned char *limit,
599 const unsigned int *hook_entries,
600 const unsigned int *underflows,
601 unsigned int valid_hooks)
602{
603 unsigned int h;
604 int err;
605
606 if ((unsigned long)e % __alignof__(struct ipt_entry) != 0 ||
607 (unsigned char *)e + sizeof(struct ipt_entry) >= limit ||
608 (unsigned char *)e + e->next_offset > limit)
609 return -EINVAL;
610
611 if (e->next_offset
612 < sizeof(struct ipt_entry) + sizeof(struct xt_entry_target))
613 return -EINVAL;
614
615 if (!ip_checkentry(&e->ip))
616 return -EINVAL;
617
618 err = xt_check_entry_offsets(e, e->elems, e->target_offset,
619 e->next_offset);
620 if (err)
621 return err;
622
623
624 for (h = 0; h < NF_INET_NUMHOOKS; h++) {
625 if (!(valid_hooks & (1 << h)))
626 continue;
627 if ((unsigned char *)e - base == hook_entries[h])
628 newinfo->hook_entry[h] = hook_entries[h];
629 if ((unsigned char *)e - base == underflows[h]) {
630 if (!check_underflow(e))
631 return -EINVAL;
632
633 newinfo->underflow[h] = underflows[h];
634 }
635 }
636
637
638 e->counters = ((struct xt_counters) { 0, 0 });
639 e->comefrom = 0;
640 return 0;
641}
642
643static void
644cleanup_entry(struct ipt_entry *e, struct net *net)
645{
646 struct xt_tgdtor_param par;
647 struct xt_entry_target *t;
648 struct xt_entry_match *ematch;
649
650
651 xt_ematch_foreach(ematch, e)
652 cleanup_match(ematch, net);
653 t = ipt_get_target(e);
654
655 par.net = net;
656 par.target = t->u.kernel.target;
657 par.targinfo = t->data;
658 par.family = NFPROTO_IPV4;
659 if (par.target->destroy != NULL)
660 par.target->destroy(&par);
661 module_put(par.target->me);
662 xt_percpu_counter_free(&e->counters);
663}
664
665
666
667static int
668translate_table(struct net *net, struct xt_table_info *newinfo, void *entry0,
669 const struct ipt_replace *repl)
670{
671 struct xt_percpu_counter_alloc_state alloc_state = { 0 };
672 struct ipt_entry *iter;
673 unsigned int *offsets;
674 unsigned int i;
675 int ret = 0;
676
677 newinfo->size = repl->size;
678 newinfo->number = repl->num_entries;
679
680
681 for (i = 0; i < NF_INET_NUMHOOKS; i++) {
682 newinfo->hook_entry[i] = 0xFFFFFFFF;
683 newinfo->underflow[i] = 0xFFFFFFFF;
684 }
685
686 offsets = xt_alloc_entry_offsets(newinfo->number);
687 if (!offsets)
688 return -ENOMEM;
689 i = 0;
690
691 xt_entry_foreach(iter, entry0, newinfo->size) {
692 ret = check_entry_size_and_hooks(iter, newinfo, entry0,
693 entry0 + repl->size,
694 repl->hook_entry,
695 repl->underflow,
696 repl->valid_hooks);
697 if (ret != 0)
698 goto out_free;
699 if (i < repl->num_entries)
700 offsets[i] = (void *)iter - entry0;
701 ++i;
702 if (strcmp(ipt_get_target(iter)->u.user.name,
703 XT_ERROR_TARGET) == 0)
704 ++newinfo->stacksize;
705 }
706
707 ret = -EINVAL;
708 if (i != repl->num_entries)
709 goto out_free;
710
711
712 for (i = 0; i < NF_INET_NUMHOOKS; i++) {
713
714 if (!(repl->valid_hooks & (1 << i)))
715 continue;
716 if (newinfo->hook_entry[i] == 0xFFFFFFFF)
717 goto out_free;
718 if (newinfo->underflow[i] == 0xFFFFFFFF)
719 goto out_free;
720 }
721
722 if (!mark_source_chains(newinfo, repl->valid_hooks, entry0, offsets)) {
723 ret = -ELOOP;
724 goto out_free;
725 }
726 kvfree(offsets);
727
728
729 i = 0;
730 xt_entry_foreach(iter, entry0, newinfo->size) {
731 ret = find_check_entry(iter, net, repl->name, repl->size,
732 &alloc_state);
733 if (ret != 0)
734 break;
735 ++i;
736 }
737
738 if (ret != 0) {
739 xt_entry_foreach(iter, entry0, newinfo->size) {
740 if (i-- == 0)
741 break;
742 cleanup_entry(iter, net);
743 }
744 return ret;
745 }
746
747 return ret;
748 out_free:
749 kvfree(offsets);
750 return ret;
751}
752
753static void
754get_counters(const struct xt_table_info *t,
755 struct xt_counters counters[])
756{
757 struct ipt_entry *iter;
758 unsigned int cpu;
759 unsigned int i;
760
761 for_each_possible_cpu(cpu) {
762 seqcount_t *s = &per_cpu(xt_recseq, cpu);
763
764 i = 0;
765 xt_entry_foreach(iter, t->entries, t->size) {
766 struct xt_counters *tmp;
767 u64 bcnt, pcnt;
768 unsigned int start;
769
770 tmp = xt_get_per_cpu_counter(&iter->counters, cpu);
771 do {
772 start = read_seqcount_begin(s);
773 bcnt = tmp->bcnt;
774 pcnt = tmp->pcnt;
775 } while (read_seqcount_retry(s, start));
776
777 ADD_COUNTER(counters[i], bcnt, pcnt);
778 ++i;
779 cond_resched();
780 }
781 }
782}
783
784static struct xt_counters *alloc_counters(const struct xt_table *table)
785{
786 unsigned int countersize;
787 struct xt_counters *counters;
788 const struct xt_table_info *private = table->private;
789
790
791
792
793 countersize = sizeof(struct xt_counters) * private->number;
794 counters = vzalloc(countersize);
795
796 if (counters == NULL)
797 return ERR_PTR(-ENOMEM);
798
799 get_counters(private, counters);
800
801 return counters;
802}
803
804static int
805copy_entries_to_user(unsigned int total_size,
806 const struct xt_table *table,
807 void __user *userptr)
808{
809 unsigned int off, num;
810 const struct ipt_entry *e;
811 struct xt_counters *counters;
812 const struct xt_table_info *private = table->private;
813 int ret = 0;
814 const void *loc_cpu_entry;
815
816 counters = alloc_counters(table);
817 if (IS_ERR(counters))
818 return PTR_ERR(counters);
819
820 loc_cpu_entry = private->entries;
821
822
823
824 for (off = 0, num = 0; off < total_size; off += e->next_offset, num++){
825 unsigned int i;
826 const struct xt_entry_match *m;
827 const struct xt_entry_target *t;
828
829 e = loc_cpu_entry + off;
830 if (copy_to_user(userptr + off, e, sizeof(*e))) {
831 ret = -EFAULT;
832 goto free_counters;
833 }
834 if (copy_to_user(userptr + off
835 + offsetof(struct ipt_entry, counters),
836 &counters[num],
837 sizeof(counters[num])) != 0) {
838 ret = -EFAULT;
839 goto free_counters;
840 }
841
842 for (i = sizeof(struct ipt_entry);
843 i < e->target_offset;
844 i += m->u.match_size) {
845 m = (void *)e + i;
846
847 if (xt_match_to_user(m, userptr + off + i)) {
848 ret = -EFAULT;
849 goto free_counters;
850 }
851 }
852
853 t = ipt_get_target_c(e);
854 if (xt_target_to_user(t, userptr + off + e->target_offset)) {
855 ret = -EFAULT;
856 goto free_counters;
857 }
858 }
859
860 free_counters:
861 vfree(counters);
862 return ret;
863}
864
865#ifdef CONFIG_COMPAT
866static void compat_standard_from_user(void *dst, const void *src)
867{
868 int v = *(compat_int_t *)src;
869
870 if (v > 0)
871 v += xt_compat_calc_jump(AF_INET, v);
872 memcpy(dst, &v, sizeof(v));
873}
874
875static int compat_standard_to_user(void __user *dst, const void *src)
876{
877 compat_int_t cv = *(int *)src;
878
879 if (cv > 0)
880 cv -= xt_compat_calc_jump(AF_INET, cv);
881 return copy_to_user(dst, &cv, sizeof(cv)) ? -EFAULT : 0;
882}
883
884static int compat_calc_entry(const struct ipt_entry *e,
885 const struct xt_table_info *info,
886 const void *base, struct xt_table_info *newinfo)
887{
888 const struct xt_entry_match *ematch;
889 const struct xt_entry_target *t;
890 unsigned int entry_offset;
891 int off, i, ret;
892
893 off = sizeof(struct ipt_entry) - sizeof(struct compat_ipt_entry);
894 entry_offset = (void *)e - base;
895 xt_ematch_foreach(ematch, e)
896 off += xt_compat_match_offset(ematch->u.kernel.match);
897 t = ipt_get_target_c(e);
898 off += xt_compat_target_offset(t->u.kernel.target);
899 newinfo->size -= off;
900 ret = xt_compat_add_offset(AF_INET, entry_offset, off);
901 if (ret)
902 return ret;
903
904 for (i = 0; i < NF_INET_NUMHOOKS; i++) {
905 if (info->hook_entry[i] &&
906 (e < (struct ipt_entry *)(base + info->hook_entry[i])))
907 newinfo->hook_entry[i] -= off;
908 if (info->underflow[i] &&
909 (e < (struct ipt_entry *)(base + info->underflow[i])))
910 newinfo->underflow[i] -= off;
911 }
912 return 0;
913}
914
915static int compat_table_info(const struct xt_table_info *info,
916 struct xt_table_info *newinfo)
917{
918 struct ipt_entry *iter;
919 const void *loc_cpu_entry;
920 int ret;
921
922 if (!newinfo || !info)
923 return -EINVAL;
924
925
926 memcpy(newinfo, info, offsetof(struct xt_table_info, entries));
927 newinfo->initial_entries = 0;
928 loc_cpu_entry = info->entries;
929 xt_compat_init_offsets(AF_INET, info->number);
930 xt_entry_foreach(iter, loc_cpu_entry, info->size) {
931 ret = compat_calc_entry(iter, info, loc_cpu_entry, newinfo);
932 if (ret != 0)
933 return ret;
934 }
935 return 0;
936}
937#endif
938
939static int get_info(struct net *net, void __user *user,
940 const int *len, int compat)
941{
942 char name[XT_TABLE_MAXNAMELEN];
943 struct xt_table *t;
944 int ret;
945
946 if (*len != sizeof(struct ipt_getinfo))
947 return -EINVAL;
948
949 if (copy_from_user(name, user, sizeof(name)) != 0)
950 return -EFAULT;
951
952 name[XT_TABLE_MAXNAMELEN-1] = '\0';
953#ifdef CONFIG_COMPAT
954 if (compat)
955 xt_compat_lock(AF_INET);
956#endif
957 t = try_then_request_module(xt_find_table_lock(net, AF_INET, name),
958 "iptable_%s", name);
959 if (t) {
960 struct ipt_getinfo info;
961 const struct xt_table_info *private = t->private;
962#ifdef CONFIG_COMPAT
963 struct xt_table_info tmp;
964
965 if (compat) {
966 ret = compat_table_info(private, &tmp);
967 xt_compat_flush_offsets(AF_INET);
968 private = &tmp;
969 }
970#endif
971 memset(&info, 0, sizeof(info));
972 info.valid_hooks = t->valid_hooks;
973 memcpy(info.hook_entry, private->hook_entry,
974 sizeof(info.hook_entry));
975 memcpy(info.underflow, private->underflow,
976 sizeof(info.underflow));
977 info.num_entries = private->number;
978 info.size = private->size;
979 strcpy(info.name, name);
980
981 if (copy_to_user(user, &info, *len) != 0)
982 ret = -EFAULT;
983 else
984 ret = 0;
985
986 xt_table_unlock(t);
987 module_put(t->me);
988 } else
989 ret = -ENOENT;
990#ifdef CONFIG_COMPAT
991 if (compat)
992 xt_compat_unlock(AF_INET);
993#endif
994 return ret;
995}
996
997static int
998get_entries(struct net *net, struct ipt_get_entries __user *uptr,
999 const int *len)
1000{
1001 int ret;
1002 struct ipt_get_entries get;
1003 struct xt_table *t;
1004
1005 if (*len < sizeof(get))
1006 return -EINVAL;
1007 if (copy_from_user(&get, uptr, sizeof(get)) != 0)
1008 return -EFAULT;
1009 if (*len != sizeof(struct ipt_get_entries) + get.size)
1010 return -EINVAL;
1011 get.name[sizeof(get.name) - 1] = '\0';
1012
1013 t = xt_find_table_lock(net, AF_INET, get.name);
1014 if (t) {
1015 const struct xt_table_info *private = t->private;
1016 if (get.size == private->size)
1017 ret = copy_entries_to_user(private->size,
1018 t, uptr->entrytable);
1019 else
1020 ret = -EAGAIN;
1021
1022 module_put(t->me);
1023 xt_table_unlock(t);
1024 } else
1025 ret = -ENOENT;
1026
1027 return ret;
1028}
1029
1030static int
1031__do_replace(struct net *net, const char *name, unsigned int valid_hooks,
1032 struct xt_table_info *newinfo, unsigned int num_counters,
1033 void __user *counters_ptr)
1034{
1035 int ret;
1036 struct xt_table *t;
1037 struct xt_table_info *oldinfo;
1038 struct xt_counters *counters;
1039 struct ipt_entry *iter;
1040
1041 ret = 0;
1042 counters = vzalloc(num_counters * sizeof(struct xt_counters));
1043 if (!counters) {
1044 ret = -ENOMEM;
1045 goto out;
1046 }
1047
1048 t = try_then_request_module(xt_find_table_lock(net, AF_INET, name),
1049 "iptable_%s", name);
1050 if (!t) {
1051 ret = -ENOENT;
1052 goto free_newinfo_counters_untrans;
1053 }
1054
1055
1056 if (valid_hooks != t->valid_hooks) {
1057 ret = -EINVAL;
1058 goto put_module;
1059 }
1060
1061 oldinfo = xt_replace_table(t, num_counters, newinfo, &ret);
1062 if (!oldinfo)
1063 goto put_module;
1064
1065
1066 if ((oldinfo->number > oldinfo->initial_entries) ||
1067 (newinfo->number <= oldinfo->initial_entries))
1068 module_put(t->me);
1069 if ((oldinfo->number > oldinfo->initial_entries) &&
1070 (newinfo->number <= oldinfo->initial_entries))
1071 module_put(t->me);
1072
1073
1074 get_counters(oldinfo, counters);
1075
1076
1077 xt_entry_foreach(iter, oldinfo->entries, oldinfo->size)
1078 cleanup_entry(iter, net);
1079
1080 xt_free_table_info(oldinfo);
1081 if (copy_to_user(counters_ptr, counters,
1082 sizeof(struct xt_counters) * num_counters) != 0) {
1083
1084 net_warn_ratelimited("iptables: counters copy to user failed while replacing table\n");
1085 }
1086 vfree(counters);
1087 xt_table_unlock(t);
1088 return ret;
1089
1090 put_module:
1091 module_put(t->me);
1092 xt_table_unlock(t);
1093 free_newinfo_counters_untrans:
1094 vfree(counters);
1095 out:
1096 return ret;
1097}
1098
1099static int
1100do_replace(struct net *net, const void __user *user, unsigned int len)
1101{
1102 int ret;
1103 struct ipt_replace tmp;
1104 struct xt_table_info *newinfo;
1105 void *loc_cpu_entry;
1106 struct ipt_entry *iter;
1107
1108 if (copy_from_user(&tmp, user, sizeof(tmp)) != 0)
1109 return -EFAULT;
1110
1111
1112 if (tmp.num_counters >= INT_MAX / sizeof(struct xt_counters))
1113 return -ENOMEM;
1114 if (tmp.num_counters == 0)
1115 return -EINVAL;
1116
1117 tmp.name[sizeof(tmp.name)-1] = 0;
1118
1119 newinfo = xt_alloc_table_info(tmp.size);
1120 if (!newinfo)
1121 return -ENOMEM;
1122
1123 loc_cpu_entry = newinfo->entries;
1124 if (copy_from_user(loc_cpu_entry, user + sizeof(tmp),
1125 tmp.size) != 0) {
1126 ret = -EFAULT;
1127 goto free_newinfo;
1128 }
1129
1130 ret = translate_table(net, newinfo, loc_cpu_entry, &tmp);
1131 if (ret != 0)
1132 goto free_newinfo;
1133
1134 ret = __do_replace(net, tmp.name, tmp.valid_hooks, newinfo,
1135 tmp.num_counters, tmp.counters);
1136 if (ret)
1137 goto free_newinfo_untrans;
1138 return 0;
1139
1140 free_newinfo_untrans:
1141 xt_entry_foreach(iter, loc_cpu_entry, newinfo->size)
1142 cleanup_entry(iter, net);
1143 free_newinfo:
1144 xt_free_table_info(newinfo);
1145 return ret;
1146}
1147
1148static int
1149do_add_counters(struct net *net, const void __user *user,
1150 unsigned int len, int compat)
1151{
1152 unsigned int i;
1153 struct xt_counters_info tmp;
1154 struct xt_counters *paddc;
1155 struct xt_table *t;
1156 const struct xt_table_info *private;
1157 int ret = 0;
1158 struct ipt_entry *iter;
1159 unsigned int addend;
1160
1161 paddc = xt_copy_counters_from_user(user, len, &tmp, compat);
1162 if (IS_ERR(paddc))
1163 return PTR_ERR(paddc);
1164
1165 t = xt_find_table_lock(net, AF_INET, tmp.name);
1166 if (!t) {
1167 ret = -ENOENT;
1168 goto free;
1169 }
1170
1171 local_bh_disable();
1172 private = t->private;
1173 if (private->number != tmp.num_counters) {
1174 ret = -EINVAL;
1175 goto unlock_up_free;
1176 }
1177
1178 i = 0;
1179 addend = xt_write_recseq_begin();
1180 xt_entry_foreach(iter, private->entries, private->size) {
1181 struct xt_counters *tmp;
1182
1183 tmp = xt_get_this_cpu_counter(&iter->counters);
1184 ADD_COUNTER(*tmp, paddc[i].bcnt, paddc[i].pcnt);
1185 ++i;
1186 }
1187 xt_write_recseq_end(addend);
1188 unlock_up_free:
1189 local_bh_enable();
1190 xt_table_unlock(t);
1191 module_put(t->me);
1192 free:
1193 vfree(paddc);
1194
1195 return ret;
1196}
1197
1198#ifdef CONFIG_COMPAT
1199struct compat_ipt_replace {
1200 char name[XT_TABLE_MAXNAMELEN];
1201 u32 valid_hooks;
1202 u32 num_entries;
1203 u32 size;
1204 u32 hook_entry[NF_INET_NUMHOOKS];
1205 u32 underflow[NF_INET_NUMHOOKS];
1206 u32 num_counters;
1207 compat_uptr_t counters;
1208 struct compat_ipt_entry entries[0];
1209};
1210
1211static int
1212compat_copy_entry_to_user(struct ipt_entry *e, void __user **dstptr,
1213 unsigned int *size, struct xt_counters *counters,
1214 unsigned int i)
1215{
1216 struct xt_entry_target *t;
1217 struct compat_ipt_entry __user *ce;
1218 u_int16_t target_offset, next_offset;
1219 compat_uint_t origsize;
1220 const struct xt_entry_match *ematch;
1221 int ret = 0;
1222
1223 origsize = *size;
1224 ce = *dstptr;
1225 if (copy_to_user(ce, e, sizeof(struct ipt_entry)) != 0 ||
1226 copy_to_user(&ce->counters, &counters[i],
1227 sizeof(counters[i])) != 0)
1228 return -EFAULT;
1229
1230 *dstptr += sizeof(struct compat_ipt_entry);
1231 *size -= sizeof(struct ipt_entry) - sizeof(struct compat_ipt_entry);
1232
1233 xt_ematch_foreach(ematch, e) {
1234 ret = xt_compat_match_to_user(ematch, dstptr, size);
1235 if (ret != 0)
1236 return ret;
1237 }
1238 target_offset = e->target_offset - (origsize - *size);
1239 t = ipt_get_target(e);
1240 ret = xt_compat_target_to_user(t, dstptr, size);
1241 if (ret)
1242 return ret;
1243 next_offset = e->next_offset - (origsize - *size);
1244 if (put_user(target_offset, &ce->target_offset) != 0 ||
1245 put_user(next_offset, &ce->next_offset) != 0)
1246 return -EFAULT;
1247 return 0;
1248}
1249
1250static int
1251compat_find_calc_match(struct xt_entry_match *m,
1252 const struct ipt_ip *ip,
1253 int *size)
1254{
1255 struct xt_match *match;
1256
1257 match = xt_request_find_match(NFPROTO_IPV4, m->u.user.name,
1258 m->u.user.revision);
1259 if (IS_ERR(match))
1260 return PTR_ERR(match);
1261
1262 m->u.kernel.match = match;
1263 *size += xt_compat_match_offset(match);
1264 return 0;
1265}
1266
1267static void compat_release_entry(struct compat_ipt_entry *e)
1268{
1269 struct xt_entry_target *t;
1270 struct xt_entry_match *ematch;
1271
1272
1273 xt_ematch_foreach(ematch, e)
1274 module_put(ematch->u.kernel.match->me);
1275 t = compat_ipt_get_target(e);
1276 module_put(t->u.kernel.target->me);
1277}
1278
1279static int
1280check_compat_entry_size_and_hooks(struct compat_ipt_entry *e,
1281 struct xt_table_info *newinfo,
1282 unsigned int *size,
1283 const unsigned char *base,
1284 const unsigned char *limit)
1285{
1286 struct xt_entry_match *ematch;
1287 struct xt_entry_target *t;
1288 struct xt_target *target;
1289 unsigned int entry_offset;
1290 unsigned int j;
1291 int ret, off;
1292
1293 if ((unsigned long)e % __alignof__(struct compat_ipt_entry) != 0 ||
1294 (unsigned char *)e + sizeof(struct compat_ipt_entry) >= limit ||
1295 (unsigned char *)e + e->next_offset > limit)
1296 return -EINVAL;
1297
1298 if (e->next_offset < sizeof(struct compat_ipt_entry) +
1299 sizeof(struct compat_xt_entry_target))
1300 return -EINVAL;
1301
1302 if (!ip_checkentry(&e->ip))
1303 return -EINVAL;
1304
1305 ret = xt_compat_check_entry_offsets(e, e->elems,
1306 e->target_offset, e->next_offset);
1307 if (ret)
1308 return ret;
1309
1310 off = sizeof(struct ipt_entry) - sizeof(struct compat_ipt_entry);
1311 entry_offset = (void *)e - (void *)base;
1312 j = 0;
1313 xt_ematch_foreach(ematch, e) {
1314 ret = compat_find_calc_match(ematch, &e->ip, &off);
1315 if (ret != 0)
1316 goto release_matches;
1317 ++j;
1318 }
1319
1320 t = compat_ipt_get_target(e);
1321 target = xt_request_find_target(NFPROTO_IPV4, t->u.user.name,
1322 t->u.user.revision);
1323 if (IS_ERR(target)) {
1324 ret = PTR_ERR(target);
1325 goto release_matches;
1326 }
1327 t->u.kernel.target = target;
1328
1329 off += xt_compat_target_offset(target);
1330 *size += off;
1331 ret = xt_compat_add_offset(AF_INET, entry_offset, off);
1332 if (ret)
1333 goto out;
1334
1335 return 0;
1336
1337out:
1338 module_put(t->u.kernel.target->me);
1339release_matches:
1340 xt_ematch_foreach(ematch, e) {
1341 if (j-- == 0)
1342 break;
1343 module_put(ematch->u.kernel.match->me);
1344 }
1345 return ret;
1346}
1347
1348static void
1349compat_copy_entry_from_user(struct compat_ipt_entry *e, void **dstptr,
1350 unsigned int *size,
1351 struct xt_table_info *newinfo, unsigned char *base)
1352{
1353 struct xt_entry_target *t;
1354 struct ipt_entry *de;
1355 unsigned int origsize;
1356 int h;
1357 struct xt_entry_match *ematch;
1358
1359 origsize = *size;
1360 de = *dstptr;
1361 memcpy(de, e, sizeof(struct ipt_entry));
1362 memcpy(&de->counters, &e->counters, sizeof(e->counters));
1363
1364 *dstptr += sizeof(struct ipt_entry);
1365 *size += sizeof(struct ipt_entry) - sizeof(struct compat_ipt_entry);
1366
1367 xt_ematch_foreach(ematch, e)
1368 xt_compat_match_from_user(ematch, dstptr, size);
1369
1370 de->target_offset = e->target_offset - (origsize - *size);
1371 t = compat_ipt_get_target(e);
1372 xt_compat_target_from_user(t, dstptr, size);
1373
1374 de->next_offset = e->next_offset - (origsize - *size);
1375
1376 for (h = 0; h < NF_INET_NUMHOOKS; h++) {
1377 if ((unsigned char *)de - base < newinfo->hook_entry[h])
1378 newinfo->hook_entry[h] -= origsize - *size;
1379 if ((unsigned char *)de - base < newinfo->underflow[h])
1380 newinfo->underflow[h] -= origsize - *size;
1381 }
1382}
1383
1384static int
1385translate_compat_table(struct net *net,
1386 struct xt_table_info **pinfo,
1387 void **pentry0,
1388 const struct compat_ipt_replace *compatr)
1389{
1390 unsigned int i, j;
1391 struct xt_table_info *newinfo, *info;
1392 void *pos, *entry0, *entry1;
1393 struct compat_ipt_entry *iter0;
1394 struct ipt_replace repl;
1395 unsigned int size;
1396 int ret;
1397
1398 info = *pinfo;
1399 entry0 = *pentry0;
1400 size = compatr->size;
1401 info->number = compatr->num_entries;
1402
1403 j = 0;
1404 xt_compat_lock(AF_INET);
1405 xt_compat_init_offsets(AF_INET, compatr->num_entries);
1406
1407 xt_entry_foreach(iter0, entry0, compatr->size) {
1408 ret = check_compat_entry_size_and_hooks(iter0, info, &size,
1409 entry0,
1410 entry0 + compatr->size);
1411 if (ret != 0)
1412 goto out_unlock;
1413 ++j;
1414 }
1415
1416 ret = -EINVAL;
1417 if (j != compatr->num_entries)
1418 goto out_unlock;
1419
1420 ret = -ENOMEM;
1421 newinfo = xt_alloc_table_info(size);
1422 if (!newinfo)
1423 goto out_unlock;
1424
1425 newinfo->number = compatr->num_entries;
1426 for (i = 0; i < NF_INET_NUMHOOKS; i++) {
1427 newinfo->hook_entry[i] = compatr->hook_entry[i];
1428 newinfo->underflow[i] = compatr->underflow[i];
1429 }
1430 entry1 = newinfo->entries;
1431 pos = entry1;
1432 size = compatr->size;
1433 xt_entry_foreach(iter0, entry0, compatr->size)
1434 compat_copy_entry_from_user(iter0, &pos, &size,
1435 newinfo, entry1);
1436
1437
1438
1439
1440
1441
1442
1443
1444 xt_compat_flush_offsets(AF_INET);
1445 xt_compat_unlock(AF_INET);
1446
1447 memcpy(&repl, compatr, sizeof(*compatr));
1448
1449 for (i = 0; i < NF_INET_NUMHOOKS; i++) {
1450 repl.hook_entry[i] = newinfo->hook_entry[i];
1451 repl.underflow[i] = newinfo->underflow[i];
1452 }
1453
1454 repl.num_counters = 0;
1455 repl.counters = NULL;
1456 repl.size = newinfo->size;
1457 ret = translate_table(net, newinfo, entry1, &repl);
1458 if (ret)
1459 goto free_newinfo;
1460
1461 *pinfo = newinfo;
1462 *pentry0 = entry1;
1463 xt_free_table_info(info);
1464 return 0;
1465
1466free_newinfo:
1467 xt_free_table_info(newinfo);
1468 return ret;
1469out_unlock:
1470 xt_compat_flush_offsets(AF_INET);
1471 xt_compat_unlock(AF_INET);
1472 xt_entry_foreach(iter0, entry0, compatr->size) {
1473 if (j-- == 0)
1474 break;
1475 compat_release_entry(iter0);
1476 }
1477 return ret;
1478}
1479
1480static int
1481compat_do_replace(struct net *net, void __user *user, unsigned int len)
1482{
1483 int ret;
1484 struct compat_ipt_replace tmp;
1485 struct xt_table_info *newinfo;
1486 void *loc_cpu_entry;
1487 struct ipt_entry *iter;
1488
1489 if (copy_from_user(&tmp, user, sizeof(tmp)) != 0)
1490 return -EFAULT;
1491
1492
1493 if (tmp.num_counters >= INT_MAX / sizeof(struct xt_counters))
1494 return -ENOMEM;
1495 if (tmp.num_counters == 0)
1496 return -EINVAL;
1497
1498 tmp.name[sizeof(tmp.name)-1] = 0;
1499
1500 newinfo = xt_alloc_table_info(tmp.size);
1501 if (!newinfo)
1502 return -ENOMEM;
1503
1504 loc_cpu_entry = newinfo->entries;
1505 if (copy_from_user(loc_cpu_entry, user + sizeof(tmp),
1506 tmp.size) != 0) {
1507 ret = -EFAULT;
1508 goto free_newinfo;
1509 }
1510
1511 ret = translate_compat_table(net, &newinfo, &loc_cpu_entry, &tmp);
1512 if (ret != 0)
1513 goto free_newinfo;
1514
1515 ret = __do_replace(net, tmp.name, tmp.valid_hooks, newinfo,
1516 tmp.num_counters, compat_ptr(tmp.counters));
1517 if (ret)
1518 goto free_newinfo_untrans;
1519 return 0;
1520
1521 free_newinfo_untrans:
1522 xt_entry_foreach(iter, loc_cpu_entry, newinfo->size)
1523 cleanup_entry(iter, net);
1524 free_newinfo:
1525 xt_free_table_info(newinfo);
1526 return ret;
1527}
1528
1529static int
1530compat_do_ipt_set_ctl(struct sock *sk, int cmd, void __user *user,
1531 unsigned int len)
1532{
1533 int ret;
1534
1535 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
1536 return -EPERM;
1537
1538 switch (cmd) {
1539 case IPT_SO_SET_REPLACE:
1540 ret = compat_do_replace(sock_net(sk), user, len);
1541 break;
1542
1543 case IPT_SO_SET_ADD_COUNTERS:
1544 ret = do_add_counters(sock_net(sk), user, len, 1);
1545 break;
1546
1547 default:
1548 ret = -EINVAL;
1549 }
1550
1551 return ret;
1552}
1553
1554struct compat_ipt_get_entries {
1555 char name[XT_TABLE_MAXNAMELEN];
1556 compat_uint_t size;
1557 struct compat_ipt_entry entrytable[0];
1558};
1559
1560static int
1561compat_copy_entries_to_user(unsigned int total_size, struct xt_table *table,
1562 void __user *userptr)
1563{
1564 struct xt_counters *counters;
1565 const struct xt_table_info *private = table->private;
1566 void __user *pos;
1567 unsigned int size;
1568 int ret = 0;
1569 unsigned int i = 0;
1570 struct ipt_entry *iter;
1571
1572 counters = alloc_counters(table);
1573 if (IS_ERR(counters))
1574 return PTR_ERR(counters);
1575
1576 pos = userptr;
1577 size = total_size;
1578 xt_entry_foreach(iter, private->entries, total_size) {
1579 ret = compat_copy_entry_to_user(iter, &pos,
1580 &size, counters, i++);
1581 if (ret != 0)
1582 break;
1583 }
1584
1585 vfree(counters);
1586 return ret;
1587}
1588
1589static int
1590compat_get_entries(struct net *net, struct compat_ipt_get_entries __user *uptr,
1591 int *len)
1592{
1593 int ret;
1594 struct compat_ipt_get_entries get;
1595 struct xt_table *t;
1596
1597 if (*len < sizeof(get))
1598 return -EINVAL;
1599
1600 if (copy_from_user(&get, uptr, sizeof(get)) != 0)
1601 return -EFAULT;
1602
1603 if (*len != sizeof(struct compat_ipt_get_entries) + get.size)
1604 return -EINVAL;
1605
1606 get.name[sizeof(get.name) - 1] = '\0';
1607
1608 xt_compat_lock(AF_INET);
1609 t = xt_find_table_lock(net, AF_INET, get.name);
1610 if (t) {
1611 const struct xt_table_info *private = t->private;
1612 struct xt_table_info info;
1613 ret = compat_table_info(private, &info);
1614 if (!ret && get.size == info.size)
1615 ret = compat_copy_entries_to_user(private->size,
1616 t, uptr->entrytable);
1617 else if (!ret)
1618 ret = -EAGAIN;
1619
1620 xt_compat_flush_offsets(AF_INET);
1621 module_put(t->me);
1622 xt_table_unlock(t);
1623 } else
1624 ret = -ENOENT;
1625
1626 xt_compat_unlock(AF_INET);
1627 return ret;
1628}
1629
1630static int do_ipt_get_ctl(struct sock *, int, void __user *, int *);
1631
1632static int
1633compat_do_ipt_get_ctl(struct sock *sk, int cmd, void __user *user, int *len)
1634{
1635 int ret;
1636
1637 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
1638 return -EPERM;
1639
1640 switch (cmd) {
1641 case IPT_SO_GET_INFO:
1642 ret = get_info(sock_net(sk), user, len, 1);
1643 break;
1644 case IPT_SO_GET_ENTRIES:
1645 ret = compat_get_entries(sock_net(sk), user, len);
1646 break;
1647 default:
1648 ret = do_ipt_get_ctl(sk, cmd, user, len);
1649 }
1650 return ret;
1651}
1652#endif
1653
1654static int
1655do_ipt_set_ctl(struct sock *sk, int cmd, void __user *user, unsigned int len)
1656{
1657 int ret;
1658
1659 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
1660 return -EPERM;
1661
1662 switch (cmd) {
1663 case IPT_SO_SET_REPLACE:
1664 ret = do_replace(sock_net(sk), user, len);
1665 break;
1666
1667 case IPT_SO_SET_ADD_COUNTERS:
1668 ret = do_add_counters(sock_net(sk), user, len, 0);
1669 break;
1670
1671 default:
1672 ret = -EINVAL;
1673 }
1674
1675 return ret;
1676}
1677
1678static int
1679do_ipt_get_ctl(struct sock *sk, int cmd, void __user *user, int *len)
1680{
1681 int ret;
1682
1683 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
1684 return -EPERM;
1685
1686 switch (cmd) {
1687 case IPT_SO_GET_INFO:
1688 ret = get_info(sock_net(sk), user, len, 0);
1689 break;
1690
1691 case IPT_SO_GET_ENTRIES:
1692 ret = get_entries(sock_net(sk), user, len);
1693 break;
1694
1695 case IPT_SO_GET_REVISION_MATCH:
1696 case IPT_SO_GET_REVISION_TARGET: {
1697 struct xt_get_revision rev;
1698 int target;
1699
1700 if (*len != sizeof(rev)) {
1701 ret = -EINVAL;
1702 break;
1703 }
1704 if (copy_from_user(&rev, user, sizeof(rev)) != 0) {
1705 ret = -EFAULT;
1706 break;
1707 }
1708 rev.name[sizeof(rev.name)-1] = 0;
1709
1710 if (cmd == IPT_SO_GET_REVISION_TARGET)
1711 target = 1;
1712 else
1713 target = 0;
1714
1715 try_then_request_module(xt_find_revision(AF_INET, rev.name,
1716 rev.revision,
1717 target, &ret),
1718 "ipt_%s", rev.name);
1719 break;
1720 }
1721
1722 default:
1723 ret = -EINVAL;
1724 }
1725
1726 return ret;
1727}
1728
1729static void __ipt_unregister_table(struct net *net, struct xt_table *table)
1730{
1731 struct xt_table_info *private;
1732 void *loc_cpu_entry;
1733 struct module *table_owner = table->me;
1734 struct ipt_entry *iter;
1735
1736 private = xt_unregister_table(table);
1737
1738
1739 loc_cpu_entry = private->entries;
1740 xt_entry_foreach(iter, loc_cpu_entry, private->size)
1741 cleanup_entry(iter, net);
1742 if (private->number > private->initial_entries)
1743 module_put(table_owner);
1744 xt_free_table_info(private);
1745}
1746
1747int ipt_register_table(struct net *net, const struct xt_table *table,
1748 const struct ipt_replace *repl,
1749 const struct nf_hook_ops *ops, struct xt_table **res)
1750{
1751 int ret;
1752 struct xt_table_info *newinfo;
1753 struct xt_table_info bootstrap = {0};
1754 void *loc_cpu_entry;
1755 struct xt_table *new_table;
1756
1757 newinfo = xt_alloc_table_info(repl->size);
1758 if (!newinfo)
1759 return -ENOMEM;
1760
1761 loc_cpu_entry = newinfo->entries;
1762 memcpy(loc_cpu_entry, repl->entries, repl->size);
1763
1764 ret = translate_table(net, newinfo, loc_cpu_entry, repl);
1765 if (ret != 0)
1766 goto out_free;
1767
1768 new_table = xt_register_table(net, table, &bootstrap, newinfo);
1769 if (IS_ERR(new_table)) {
1770 ret = PTR_ERR(new_table);
1771 goto out_free;
1772 }
1773
1774
1775 WRITE_ONCE(*res, new_table);
1776
1777 ret = nf_register_net_hooks(net, ops, hweight32(table->valid_hooks));
1778 if (ret != 0) {
1779 __ipt_unregister_table(net, new_table);
1780 *res = NULL;
1781 }
1782
1783 return ret;
1784
1785out_free:
1786 xt_free_table_info(newinfo);
1787 return ret;
1788}
1789
1790void ipt_unregister_table(struct net *net, struct xt_table *table,
1791 const struct nf_hook_ops *ops)
1792{
1793 nf_unregister_net_hooks(net, ops, hweight32(table->valid_hooks));
1794 __ipt_unregister_table(net, table);
1795}
1796
1797
1798static inline bool
1799icmp_type_code_match(u_int8_t test_type, u_int8_t min_code, u_int8_t max_code,
1800 u_int8_t type, u_int8_t code,
1801 bool invert)
1802{
1803 return ((test_type == 0xFF) ||
1804 (type == test_type && code >= min_code && code <= max_code))
1805 ^ invert;
1806}
1807
1808static bool
1809icmp_match(const struct sk_buff *skb, struct xt_action_param *par)
1810{
1811 const struct icmphdr *ic;
1812 struct icmphdr _icmph;
1813 const struct ipt_icmp *icmpinfo = par->matchinfo;
1814
1815
1816 if (par->fragoff != 0)
1817 return false;
1818
1819 ic = skb_header_pointer(skb, par->thoff, sizeof(_icmph), &_icmph);
1820 if (ic == NULL) {
1821
1822
1823
1824 par->hotdrop = true;
1825 return false;
1826 }
1827
1828 return icmp_type_code_match(icmpinfo->type,
1829 icmpinfo->code[0],
1830 icmpinfo->code[1],
1831 ic->type, ic->code,
1832 !!(icmpinfo->invflags&IPT_ICMP_INV));
1833}
1834
1835static int icmp_checkentry(const struct xt_mtchk_param *par)
1836{
1837 const struct ipt_icmp *icmpinfo = par->matchinfo;
1838
1839
1840 return (icmpinfo->invflags & ~IPT_ICMP_INV) ? -EINVAL : 0;
1841}
1842
1843static struct xt_target ipt_builtin_tg[] __read_mostly = {
1844 {
1845 .name = XT_STANDARD_TARGET,
1846 .targetsize = sizeof(int),
1847 .family = NFPROTO_IPV4,
1848#ifdef CONFIG_COMPAT
1849 .compatsize = sizeof(compat_int_t),
1850 .compat_from_user = compat_standard_from_user,
1851 .compat_to_user = compat_standard_to_user,
1852#endif
1853 },
1854 {
1855 .name = XT_ERROR_TARGET,
1856 .target = ipt_error,
1857 .targetsize = XT_FUNCTION_MAXNAMELEN,
1858 .family = NFPROTO_IPV4,
1859 },
1860};
1861
1862static struct nf_sockopt_ops ipt_sockopts = {
1863 .pf = PF_INET,
1864 .set_optmin = IPT_BASE_CTL,
1865 .set_optmax = IPT_SO_SET_MAX+1,
1866 .set = do_ipt_set_ctl,
1867#ifdef CONFIG_COMPAT
1868 .compat_set = compat_do_ipt_set_ctl,
1869#endif
1870 .get_optmin = IPT_BASE_CTL,
1871 .get_optmax = IPT_SO_GET_MAX+1,
1872 .get = do_ipt_get_ctl,
1873#ifdef CONFIG_COMPAT
1874 .compat_get = compat_do_ipt_get_ctl,
1875#endif
1876 .owner = THIS_MODULE,
1877};
1878
1879static struct xt_match ipt_builtin_mt[] __read_mostly = {
1880 {
1881 .name = "icmp",
1882 .match = icmp_match,
1883 .matchsize = sizeof(struct ipt_icmp),
1884 .checkentry = icmp_checkentry,
1885 .proto = IPPROTO_ICMP,
1886 .family = NFPROTO_IPV4,
1887 },
1888};
1889
1890static int __net_init ip_tables_net_init(struct net *net)
1891{
1892 return xt_proto_init(net, NFPROTO_IPV4);
1893}
1894
1895static void __net_exit ip_tables_net_exit(struct net *net)
1896{
1897 xt_proto_fini(net, NFPROTO_IPV4);
1898}
1899
1900static struct pernet_operations ip_tables_net_ops = {
1901 .init = ip_tables_net_init,
1902 .exit = ip_tables_net_exit,
1903};
1904
1905static int __init ip_tables_init(void)
1906{
1907 int ret;
1908
1909 ret = register_pernet_subsys(&ip_tables_net_ops);
1910 if (ret < 0)
1911 goto err1;
1912
1913
1914 ret = xt_register_targets(ipt_builtin_tg, ARRAY_SIZE(ipt_builtin_tg));
1915 if (ret < 0)
1916 goto err2;
1917 ret = xt_register_matches(ipt_builtin_mt, ARRAY_SIZE(ipt_builtin_mt));
1918 if (ret < 0)
1919 goto err4;
1920
1921
1922 ret = nf_register_sockopt(&ipt_sockopts);
1923 if (ret < 0)
1924 goto err5;
1925
1926 pr_info("(C) 2000-2006 Netfilter Core Team\n");
1927 return 0;
1928
1929err5:
1930 xt_unregister_matches(ipt_builtin_mt, ARRAY_SIZE(ipt_builtin_mt));
1931err4:
1932 xt_unregister_targets(ipt_builtin_tg, ARRAY_SIZE(ipt_builtin_tg));
1933err2:
1934 unregister_pernet_subsys(&ip_tables_net_ops);
1935err1:
1936 return ret;
1937}
1938
1939static void __exit ip_tables_fini(void)
1940{
1941 nf_unregister_sockopt(&ipt_sockopts);
1942
1943 xt_unregister_matches(ipt_builtin_mt, ARRAY_SIZE(ipt_builtin_mt));
1944 xt_unregister_targets(ipt_builtin_tg, ARRAY_SIZE(ipt_builtin_tg));
1945 unregister_pernet_subsys(&ip_tables_net_ops);
1946}
1947
1948EXPORT_SYMBOL(ipt_register_table);
1949EXPORT_SYMBOL(ipt_unregister_table);
1950EXPORT_SYMBOL(ipt_do_table);
1951module_init(ip_tables_init);
1952module_exit(ip_tables_fini);
1953
