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8
9#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
10#include <linux/cache.h>
11#include <linux/capability.h>
12#include <linux/skbuff.h>
13#include <linux/kmod.h>
14#include <linux/vmalloc.h>
15#include <linux/netdevice.h>
16#include <linux/module.h>
17#include <linux/icmp.h>
18#include <net/ip.h>
19#include <net/compat.h>
20#include <linux/uaccess.h>
21#include <linux/mutex.h>
22#include <linux/proc_fs.h>
23#include <linux/err.h>
24#include <linux/cpumask.h>
25
26#include <linux/netfilter/x_tables.h>
27#include <linux/netfilter_ipv4/ip_tables.h>
28#include <net/netfilter/nf_log.h>
29#include "../../netfilter/xt_repldata.h"
30
31MODULE_LICENSE("GPL");
32MODULE_AUTHOR("Netfilter Core Team <coreteam@netfilter.org>");
33MODULE_DESCRIPTION("IPv4 packet filter");
34MODULE_ALIAS("ipt_icmp");
35
36void *ipt_alloc_initial_table(const struct xt_table *info)
37{
38 return xt_alloc_initial_table(ipt, IPT);
39}
40EXPORT_SYMBOL_GPL(ipt_alloc_initial_table);
41
42
43
44static inline bool
45ip_packet_match(const struct iphdr *ip,
46 const char *indev,
47 const char *outdev,
48 const struct ipt_ip *ipinfo,
49 int isfrag)
50{
51 unsigned long ret;
52
53 if (NF_INVF(ipinfo, IPT_INV_SRCIP,
54 (ip->saddr & ipinfo->smsk.s_addr) != ipinfo->src.s_addr) ||
55 NF_INVF(ipinfo, IPT_INV_DSTIP,
56 (ip->daddr & ipinfo->dmsk.s_addr) != ipinfo->dst.s_addr))
57 return false;
58
59 ret = ifname_compare_aligned(indev, ipinfo->iniface, ipinfo->iniface_mask);
60
61 if (NF_INVF(ipinfo, IPT_INV_VIA_IN, ret != 0))
62 return false;
63
64 ret = ifname_compare_aligned(outdev, ipinfo->outiface, ipinfo->outiface_mask);
65
66 if (NF_INVF(ipinfo, IPT_INV_VIA_OUT, ret != 0))
67 return false;
68
69
70 if (ipinfo->proto &&
71 NF_INVF(ipinfo, IPT_INV_PROTO, ip->protocol != ipinfo->proto))
72 return false;
73
74
75
76 if (NF_INVF(ipinfo, IPT_INV_FRAG,
77 (ipinfo->flags & IPT_F_FRAG) && !isfrag))
78 return false;
79
80 return true;
81}
82
83static bool
84ip_checkentry(const struct ipt_ip *ip)
85{
86 if (ip->flags & ~IPT_F_MASK)
87 return false;
88 if (ip->invflags & ~IPT_INV_MASK)
89 return false;
90 return true;
91}
92
93static unsigned int
94ipt_error(struct sk_buff *skb, const struct xt_action_param *par)
95{
96 net_info_ratelimited("error: `%s'\n", (const char *)par->targinfo);
97
98 return NF_DROP;
99}
100
101
102static inline struct ipt_entry *
103get_entry(const void *base, unsigned int offset)
104{
105 return (struct ipt_entry *)(base + offset);
106}
107
108
109
110static inline bool unconditional(const struct ipt_entry *e)
111{
112 static const struct ipt_ip uncond;
113
114 return e->target_offset == sizeof(struct ipt_entry) &&
115 memcmp(&e->ip, &uncond, sizeof(uncond)) == 0;
116}
117
118
119static inline const struct xt_entry_target *
120ipt_get_target_c(const struct ipt_entry *e)
121{
122 return ipt_get_target((struct ipt_entry *)e);
123}
124
125#if IS_ENABLED(CONFIG_NETFILTER_XT_TARGET_TRACE)
126static const char *const hooknames[] = {
127 [NF_INET_PRE_ROUTING] = "PREROUTING",
128 [NF_INET_LOCAL_IN] = "INPUT",
129 [NF_INET_FORWARD] = "FORWARD",
130 [NF_INET_LOCAL_OUT] = "OUTPUT",
131 [NF_INET_POST_ROUTING] = "POSTROUTING",
132};
133
134enum nf_ip_trace_comments {
135 NF_IP_TRACE_COMMENT_RULE,
136 NF_IP_TRACE_COMMENT_RETURN,
137 NF_IP_TRACE_COMMENT_POLICY,
138};
139
140static const char *const comments[] = {
141 [NF_IP_TRACE_COMMENT_RULE] = "rule",
142 [NF_IP_TRACE_COMMENT_RETURN] = "return",
143 [NF_IP_TRACE_COMMENT_POLICY] = "policy",
144};
145
146static const struct nf_loginfo trace_loginfo = {
147 .type = NF_LOG_TYPE_LOG,
148 .u = {
149 .log = {
150 .level = 4,
151 .logflags = NF_LOG_DEFAULT_MASK,
152 },
153 },
154};
155
156
157static inline int
158get_chainname_rulenum(const struct ipt_entry *s, const struct ipt_entry *e,
159 const char *hookname, const char **chainname,
160 const char **comment, unsigned int *rulenum)
161{
162 const struct xt_standard_target *t = (void *)ipt_get_target_c(s);
163
164 if (strcmp(t->target.u.kernel.target->name, XT_ERROR_TARGET) == 0) {
165
166 *chainname = t->target.data;
167 (*rulenum) = 0;
168 } else if (s == e) {
169 (*rulenum)++;
170
171 if (unconditional(s) &&
172 strcmp(t->target.u.kernel.target->name,
173 XT_STANDARD_TARGET) == 0 &&
174 t->verdict < 0) {
175
176 *comment = *chainname == hookname
177 ? comments[NF_IP_TRACE_COMMENT_POLICY]
178 : comments[NF_IP_TRACE_COMMENT_RETURN];
179 }
180 return 1;
181 } else
182 (*rulenum)++;
183
184 return 0;
185}
186
187static void trace_packet(struct net *net,
188 const struct sk_buff *skb,
189 unsigned int hook,
190 const struct net_device *in,
191 const struct net_device *out,
192 const char *tablename,
193 const struct xt_table_info *private,
194 const struct ipt_entry *e)
195{
196 const struct ipt_entry *root;
197 const char *hookname, *chainname, *comment;
198 const struct ipt_entry *iter;
199 unsigned int rulenum = 0;
200
201 root = get_entry(private->entries, private->hook_entry[hook]);
202
203 hookname = chainname = hooknames[hook];
204 comment = comments[NF_IP_TRACE_COMMENT_RULE];
205
206 xt_entry_foreach(iter, root, private->size - private->hook_entry[hook])
207 if (get_chainname_rulenum(iter, e, hookname,
208 &chainname, &comment, &rulenum) != 0)
209 break;
210
211 nf_log_trace(net, AF_INET, hook, skb, in, out, &trace_loginfo,
212 "TRACE: %s:%s:%s:%u ",
213 tablename, chainname, comment, rulenum);
214}
215#endif
216
217static inline
218struct ipt_entry *ipt_next_entry(const struct ipt_entry *entry)
219{
220 return (void *)entry + entry->next_offset;
221}
222
223
224unsigned int
225ipt_do_table(struct sk_buff *skb,
226 const struct nf_hook_state *state,
227 struct xt_table *table)
228{
229 unsigned int hook = state->hook;
230 static const char nulldevname[IFNAMSIZ] __attribute__((aligned(sizeof(long))));
231 const struct iphdr *ip;
232
233 unsigned int verdict = NF_DROP;
234 const char *indev, *outdev;
235 const void *table_base;
236 struct ipt_entry *e, **jumpstack;
237 unsigned int stackidx, cpu;
238 const struct xt_table_info *private;
239 struct xt_action_param acpar;
240 unsigned int addend;
241
242
243 stackidx = 0;
244 ip = ip_hdr(skb);
245 indev = state->in ? state->in->name : nulldevname;
246 outdev = state->out ? state->out->name : nulldevname;
247
248
249
250
251
252
253 acpar.fragoff = ntohs(ip->frag_off) & IP_OFFSET;
254 acpar.thoff = ip_hdrlen(skb);
255 acpar.hotdrop = false;
256 acpar.state = state;
257
258 WARN_ON(!(table->valid_hooks & (1 << hook)));
259 local_bh_disable();
260 addend = xt_write_recseq_begin();
261 private = READ_ONCE(table->private);
262 cpu = smp_processor_id();
263 table_base = private->entries;
264 jumpstack = (struct ipt_entry **)private->jumpstack[cpu];
265
266
267
268
269
270
271
272
273 if (static_key_false(&xt_tee_enabled))
274 jumpstack += private->stacksize * __this_cpu_read(nf_skb_duplicated);
275
276 e = get_entry(table_base, private->hook_entry[hook]);
277
278 do {
279 const struct xt_entry_target *t;
280 const struct xt_entry_match *ematch;
281 struct xt_counters *counter;
282
283 WARN_ON(!e);
284 if (!ip_packet_match(ip, indev, outdev,
285 &e->ip, acpar.fragoff)) {
286 no_match:
287 e = ipt_next_entry(e);
288 continue;
289 }
290
291 xt_ematch_foreach(ematch, e) {
292 acpar.match = ematch->u.kernel.match;
293 acpar.matchinfo = ematch->data;
294 if (!acpar.match->match(skb, &acpar))
295 goto no_match;
296 }
297
298 counter = xt_get_this_cpu_counter(&e->counters);
299 ADD_COUNTER(*counter, skb->len, 1);
300
301 t = ipt_get_target_c(e);
302 WARN_ON(!t->u.kernel.target);
303
304#if IS_ENABLED(CONFIG_NETFILTER_XT_TARGET_TRACE)
305
306 if (unlikely(skb->nf_trace))
307 trace_packet(state->net, skb, hook, state->in,
308 state->out, table->name, private, e);
309#endif
310
311 if (!t->u.kernel.target->target) {
312 int v;
313
314 v = ((struct xt_standard_target *)t)->verdict;
315 if (v < 0) {
316
317 if (v != XT_RETURN) {
318 verdict = (unsigned int)(-v) - 1;
319 break;
320 }
321 if (stackidx == 0) {
322 e = get_entry(table_base,
323 private->underflow[hook]);
324 } else {
325 e = jumpstack[--stackidx];
326 e = ipt_next_entry(e);
327 }
328 continue;
329 }
330 if (table_base + v != ipt_next_entry(e) &&
331 !(e->ip.flags & IPT_F_GOTO)) {
332 if (unlikely(stackidx >= private->stacksize)) {
333 verdict = NF_DROP;
334 break;
335 }
336 jumpstack[stackidx++] = e;
337 }
338
339 e = get_entry(table_base, v);
340 continue;
341 }
342
343 acpar.target = t->u.kernel.target;
344 acpar.targinfo = t->data;
345
346 verdict = t->u.kernel.target->target(skb, &acpar);
347 if (verdict == XT_CONTINUE) {
348
349 ip = ip_hdr(skb);
350 e = ipt_next_entry(e);
351 } else {
352
353 break;
354 }
355 } while (!acpar.hotdrop);
356
357 xt_write_recseq_end(addend);
358 local_bh_enable();
359
360 if (acpar.hotdrop)
361 return NF_DROP;
362 else return verdict;
363}
364
365
366
367static int
368mark_source_chains(const struct xt_table_info *newinfo,
369 unsigned int valid_hooks, void *entry0,
370 unsigned int *offsets)
371{
372 unsigned int hook;
373
374
375
376 for (hook = 0; hook < NF_INET_NUMHOOKS; hook++) {
377 unsigned int pos = newinfo->hook_entry[hook];
378 struct ipt_entry *e = entry0 + pos;
379
380 if (!(valid_hooks & (1 << hook)))
381 continue;
382
383
384 e->counters.pcnt = pos;
385
386 for (;;) {
387 const struct xt_standard_target *t
388 = (void *)ipt_get_target_c(e);
389 int visited = e->comefrom & (1 << hook);
390
391 if (e->comefrom & (1 << NF_INET_NUMHOOKS))
392 return 0;
393
394 e->comefrom |= ((1 << hook) | (1 << NF_INET_NUMHOOKS));
395
396
397 if ((unconditional(e) &&
398 (strcmp(t->target.u.user.name,
399 XT_STANDARD_TARGET) == 0) &&
400 t->verdict < 0) || visited) {
401 unsigned int oldpos, size;
402
403
404
405 do {
406 e->comefrom ^= (1<<NF_INET_NUMHOOKS);
407 oldpos = pos;
408 pos = e->counters.pcnt;
409 e->counters.pcnt = 0;
410
411
412 if (pos == oldpos)
413 goto next;
414
415 e = entry0 + pos;
416 } while (oldpos == pos + e->next_offset);
417
418
419 size = e->next_offset;
420 e = entry0 + pos + size;
421 if (pos + size >= newinfo->size)
422 return 0;
423 e->counters.pcnt = pos;
424 pos += size;
425 } else {
426 int newpos = t->verdict;
427
428 if (strcmp(t->target.u.user.name,
429 XT_STANDARD_TARGET) == 0 &&
430 newpos >= 0) {
431
432 if (!xt_find_jump_offset(offsets, newpos,
433 newinfo->number))
434 return 0;
435 } else {
436
437 newpos = pos + e->next_offset;
438 if (newpos >= newinfo->size)
439 return 0;
440 }
441 e = entry0 + newpos;
442 e->counters.pcnt = pos;
443 pos = newpos;
444 }
445 }
446next: ;
447 }
448 return 1;
449}
450
451static void cleanup_match(struct xt_entry_match *m, struct net *net)
452{
453 struct xt_mtdtor_param par;
454
455 par.net = net;
456 par.match = m->u.kernel.match;
457 par.matchinfo = m->data;
458 par.family = NFPROTO_IPV4;
459 if (par.match->destroy != NULL)
460 par.match->destroy(&par);
461 module_put(par.match->me);
462}
463
464static int
465check_match(struct xt_entry_match *m, struct xt_mtchk_param *par)
466{
467 const struct ipt_ip *ip = par->entryinfo;
468
469 par->match = m->u.kernel.match;
470 par->matchinfo = m->data;
471
472 return xt_check_match(par, m->u.match_size - sizeof(*m),
473 ip->proto, ip->invflags & IPT_INV_PROTO);
474}
475
476static int
477find_check_match(struct xt_entry_match *m, struct xt_mtchk_param *par)
478{
479 struct xt_match *match;
480 int ret;
481
482 match = xt_request_find_match(NFPROTO_IPV4, m->u.user.name,
483 m->u.user.revision);
484 if (IS_ERR(match))
485 return PTR_ERR(match);
486 m->u.kernel.match = match;
487
488 ret = check_match(m, par);
489 if (ret)
490 goto err;
491
492 return 0;
493err:
494 module_put(m->u.kernel.match->me);
495 return ret;
496}
497
498static int check_target(struct ipt_entry *e, struct net *net, const char *name)
499{
500 struct xt_entry_target *t = ipt_get_target(e);
501 struct xt_tgchk_param par = {
502 .net = net,
503 .table = name,
504 .entryinfo = e,
505 .target = t->u.kernel.target,
506 .targinfo = t->data,
507 .hook_mask = e->comefrom,
508 .family = NFPROTO_IPV4,
509 };
510
511 return xt_check_target(&par, t->u.target_size - sizeof(*t),
512 e->ip.proto, e->ip.invflags & IPT_INV_PROTO);
513}
514
515static int
516find_check_entry(struct ipt_entry *e, struct net *net, const char *name,
517 unsigned int size,
518 struct xt_percpu_counter_alloc_state *alloc_state)
519{
520 struct xt_entry_target *t;
521 struct xt_target *target;
522 int ret;
523 unsigned int j;
524 struct xt_mtchk_param mtpar;
525 struct xt_entry_match *ematch;
526
527 if (!xt_percpu_counter_alloc(alloc_state, &e->counters))
528 return -ENOMEM;
529
530 j = 0;
531 memset(&mtpar, 0, sizeof(mtpar));
532 mtpar.net = net;
533 mtpar.table = name;
534 mtpar.entryinfo = &e->ip;
535 mtpar.hook_mask = e->comefrom;
536 mtpar.family = NFPROTO_IPV4;
537 xt_ematch_foreach(ematch, e) {
538 ret = find_check_match(ematch, &mtpar);
539 if (ret != 0)
540 goto cleanup_matches;
541 ++j;
542 }
543
544 t = ipt_get_target(e);
545 target = xt_request_find_target(NFPROTO_IPV4, t->u.user.name,
546 t->u.user.revision);
547 if (IS_ERR(target)) {
548 ret = PTR_ERR(target);
549 goto cleanup_matches;
550 }
551 t->u.kernel.target = target;
552
553 ret = check_target(e, net, name);
554 if (ret)
555 goto err;
556
557 return 0;
558 err:
559 module_put(t->u.kernel.target->me);
560 cleanup_matches:
561 xt_ematch_foreach(ematch, e) {
562 if (j-- == 0)
563 break;
564 cleanup_match(ematch, net);
565 }
566
567 xt_percpu_counter_free(&e->counters);
568
569 return ret;
570}
571
572static bool check_underflow(const struct ipt_entry *e)
573{
574 const struct xt_entry_target *t;
575 unsigned int verdict;
576
577 if (!unconditional(e))
578 return false;
579 t = ipt_get_target_c(e);
580 if (strcmp(t->u.user.name, XT_STANDARD_TARGET) != 0)
581 return false;
582 verdict = ((struct xt_standard_target *)t)->verdict;
583 verdict = -verdict - 1;
584 return verdict == NF_DROP || verdict == NF_ACCEPT;
585}
586
587static int
588check_entry_size_and_hooks(struct ipt_entry *e,
589 struct xt_table_info *newinfo,
590 const unsigned char *base,
591 const unsigned char *limit,
592 const unsigned int *hook_entries,
593 const unsigned int *underflows,
594 unsigned int valid_hooks)
595{
596 unsigned int h;
597 int err;
598
599 if ((unsigned long)e % __alignof__(struct ipt_entry) != 0 ||
600 (unsigned char *)e + sizeof(struct ipt_entry) >= limit ||
601 (unsigned char *)e + e->next_offset > limit)
602 return -EINVAL;
603
604 if (e->next_offset
605 < sizeof(struct ipt_entry) + sizeof(struct xt_entry_target))
606 return -EINVAL;
607
608 if (!ip_checkentry(&e->ip))
609 return -EINVAL;
610
611 err = xt_check_entry_offsets(e, e->elems, e->target_offset,
612 e->next_offset);
613 if (err)
614 return err;
615
616
617 for (h = 0; h < NF_INET_NUMHOOKS; h++) {
618 if (!(valid_hooks & (1 << h)))
619 continue;
620 if ((unsigned char *)e - base == hook_entries[h])
621 newinfo->hook_entry[h] = hook_entries[h];
622 if ((unsigned char *)e - base == underflows[h]) {
623 if (!check_underflow(e))
624 return -EINVAL;
625
626 newinfo->underflow[h] = underflows[h];
627 }
628 }
629
630
631 e->counters = ((struct xt_counters) { 0, 0 });
632 e->comefrom = 0;
633 return 0;
634}
635
636static void
637cleanup_entry(struct ipt_entry *e, struct net *net)
638{
639 struct xt_tgdtor_param par;
640 struct xt_entry_target *t;
641 struct xt_entry_match *ematch;
642
643
644 xt_ematch_foreach(ematch, e)
645 cleanup_match(ematch, net);
646 t = ipt_get_target(e);
647
648 par.net = net;
649 par.target = t->u.kernel.target;
650 par.targinfo = t->data;
651 par.family = NFPROTO_IPV4;
652 if (par.target->destroy != NULL)
653 par.target->destroy(&par);
654 module_put(par.target->me);
655 xt_percpu_counter_free(&e->counters);
656}
657
658
659
660static int
661translate_table(struct net *net, struct xt_table_info *newinfo, void *entry0,
662 const struct ipt_replace *repl)
663{
664 struct xt_percpu_counter_alloc_state alloc_state = { 0 };
665 struct ipt_entry *iter;
666 unsigned int *offsets;
667 unsigned int i;
668 int ret = 0;
669
670 newinfo->size = repl->size;
671 newinfo->number = repl->num_entries;
672
673
674 for (i = 0; i < NF_INET_NUMHOOKS; i++) {
675 newinfo->hook_entry[i] = 0xFFFFFFFF;
676 newinfo->underflow[i] = 0xFFFFFFFF;
677 }
678
679 offsets = xt_alloc_entry_offsets(newinfo->number);
680 if (!offsets)
681 return -ENOMEM;
682 i = 0;
683
684 xt_entry_foreach(iter, entry0, newinfo->size) {
685 ret = check_entry_size_and_hooks(iter, newinfo, entry0,
686 entry0 + repl->size,
687 repl->hook_entry,
688 repl->underflow,
689 repl->valid_hooks);
690 if (ret != 0)
691 goto out_free;
692 if (i < repl->num_entries)
693 offsets[i] = (void *)iter - entry0;
694 ++i;
695 if (strcmp(ipt_get_target(iter)->u.user.name,
696 XT_ERROR_TARGET) == 0)
697 ++newinfo->stacksize;
698 }
699
700 ret = -EINVAL;
701 if (i != repl->num_entries)
702 goto out_free;
703
704 ret = xt_check_table_hooks(newinfo, repl->valid_hooks);
705 if (ret)
706 goto out_free;
707
708 if (!mark_source_chains(newinfo, repl->valid_hooks, entry0, offsets)) {
709 ret = -ELOOP;
710 goto out_free;
711 }
712 kvfree(offsets);
713
714
715 i = 0;
716 xt_entry_foreach(iter, entry0, newinfo->size) {
717 ret = find_check_entry(iter, net, repl->name, repl->size,
718 &alloc_state);
719 if (ret != 0)
720 break;
721 ++i;
722 }
723
724 if (ret != 0) {
725 xt_entry_foreach(iter, entry0, newinfo->size) {
726 if (i-- == 0)
727 break;
728 cleanup_entry(iter, net);
729 }
730 return ret;
731 }
732
733 return ret;
734 out_free:
735 kvfree(offsets);
736 return ret;
737}
738
739static void
740get_counters(const struct xt_table_info *t,
741 struct xt_counters counters[])
742{
743 struct ipt_entry *iter;
744 unsigned int cpu;
745 unsigned int i;
746
747 for_each_possible_cpu(cpu) {
748 seqcount_t *s = &per_cpu(xt_recseq, cpu);
749
750 i = 0;
751 xt_entry_foreach(iter, t->entries, t->size) {
752 struct xt_counters *tmp;
753 u64 bcnt, pcnt;
754 unsigned int start;
755
756 tmp = xt_get_per_cpu_counter(&iter->counters, cpu);
757 do {
758 start = read_seqcount_begin(s);
759 bcnt = tmp->bcnt;
760 pcnt = tmp->pcnt;
761 } while (read_seqcount_retry(s, start));
762
763 ADD_COUNTER(counters[i], bcnt, pcnt);
764 ++i;
765 cond_resched();
766 }
767 }
768}
769
770static void get_old_counters(const struct xt_table_info *t,
771 struct xt_counters counters[])
772{
773 struct ipt_entry *iter;
774 unsigned int cpu, i;
775
776 for_each_possible_cpu(cpu) {
777 i = 0;
778 xt_entry_foreach(iter, t->entries, t->size) {
779 const struct xt_counters *tmp;
780
781 tmp = xt_get_per_cpu_counter(&iter->counters, cpu);
782 ADD_COUNTER(counters[i], tmp->bcnt, tmp->pcnt);
783 ++i;
784 }
785
786 cond_resched();
787 }
788}
789
790static struct xt_counters *alloc_counters(const struct xt_table *table)
791{
792 unsigned int countersize;
793 struct xt_counters *counters;
794 const struct xt_table_info *private = table->private;
795
796
797
798
799 countersize = sizeof(struct xt_counters) * private->number;
800 counters = vzalloc(countersize);
801
802 if (counters == NULL)
803 return ERR_PTR(-ENOMEM);
804
805 get_counters(private, counters);
806
807 return counters;
808}
809
810static int
811copy_entries_to_user(unsigned int total_size,
812 const struct xt_table *table,
813 void __user *userptr)
814{
815 unsigned int off, num;
816 const struct ipt_entry *e;
817 struct xt_counters *counters;
818 const struct xt_table_info *private = table->private;
819 int ret = 0;
820 const void *loc_cpu_entry;
821
822 counters = alloc_counters(table);
823 if (IS_ERR(counters))
824 return PTR_ERR(counters);
825
826 loc_cpu_entry = private->entries;
827
828
829
830 for (off = 0, num = 0; off < total_size; off += e->next_offset, num++){
831 unsigned int i;
832 const struct xt_entry_match *m;
833 const struct xt_entry_target *t;
834
835 e = loc_cpu_entry + off;
836 if (copy_to_user(userptr + off, e, sizeof(*e))) {
837 ret = -EFAULT;
838 goto free_counters;
839 }
840 if (copy_to_user(userptr + off
841 + offsetof(struct ipt_entry, counters),
842 &counters[num],
843 sizeof(counters[num])) != 0) {
844 ret = -EFAULT;
845 goto free_counters;
846 }
847
848 for (i = sizeof(struct ipt_entry);
849 i < e->target_offset;
850 i += m->u.match_size) {
851 m = (void *)e + i;
852
853 if (xt_match_to_user(m, userptr + off + i)) {
854 ret = -EFAULT;
855 goto free_counters;
856 }
857 }
858
859 t = ipt_get_target_c(e);
860 if (xt_target_to_user(t, userptr + off + e->target_offset)) {
861 ret = -EFAULT;
862 goto free_counters;
863 }
864 }
865
866 free_counters:
867 vfree(counters);
868 return ret;
869}
870
871#ifdef CONFIG_NETFILTER_XTABLES_COMPAT
872static void compat_standard_from_user(void *dst, const void *src)
873{
874 int v = *(compat_int_t *)src;
875
876 if (v > 0)
877 v += xt_compat_calc_jump(AF_INET, v);
878 memcpy(dst, &v, sizeof(v));
879}
880
881static int compat_standard_to_user(void __user *dst, const void *src)
882{
883 compat_int_t cv = *(int *)src;
884
885 if (cv > 0)
886 cv -= xt_compat_calc_jump(AF_INET, cv);
887 return copy_to_user(dst, &cv, sizeof(cv)) ? -EFAULT : 0;
888}
889
890static int compat_calc_entry(const struct ipt_entry *e,
891 const struct xt_table_info *info,
892 const void *base, struct xt_table_info *newinfo)
893{
894 const struct xt_entry_match *ematch;
895 const struct xt_entry_target *t;
896 unsigned int entry_offset;
897 int off, i, ret;
898
899 off = sizeof(struct ipt_entry) - sizeof(struct compat_ipt_entry);
900 entry_offset = (void *)e - base;
901 xt_ematch_foreach(ematch, e)
902 off += xt_compat_match_offset(ematch->u.kernel.match);
903 t = ipt_get_target_c(e);
904 off += xt_compat_target_offset(t->u.kernel.target);
905 newinfo->size -= off;
906 ret = xt_compat_add_offset(AF_INET, entry_offset, off);
907 if (ret)
908 return ret;
909
910 for (i = 0; i < NF_INET_NUMHOOKS; i++) {
911 if (info->hook_entry[i] &&
912 (e < (struct ipt_entry *)(base + info->hook_entry[i])))
913 newinfo->hook_entry[i] -= off;
914 if (info->underflow[i] &&
915 (e < (struct ipt_entry *)(base + info->underflow[i])))
916 newinfo->underflow[i] -= off;
917 }
918 return 0;
919}
920
921static int compat_table_info(const struct xt_table_info *info,
922 struct xt_table_info *newinfo)
923{
924 struct ipt_entry *iter;
925 const void *loc_cpu_entry;
926 int ret;
927
928 if (!newinfo || !info)
929 return -EINVAL;
930
931
932 memcpy(newinfo, info, offsetof(struct xt_table_info, entries));
933 newinfo->initial_entries = 0;
934 loc_cpu_entry = info->entries;
935 ret = xt_compat_init_offsets(AF_INET, info->number);
936 if (ret)
937 return ret;
938 xt_entry_foreach(iter, loc_cpu_entry, info->size) {
939 ret = compat_calc_entry(iter, info, loc_cpu_entry, newinfo);
940 if (ret != 0)
941 return ret;
942 }
943 return 0;
944}
945#endif
946
947static int get_info(struct net *net, void __user *user, const int *len)
948{
949 char name[XT_TABLE_MAXNAMELEN];
950 struct xt_table *t;
951 int ret;
952
953 if (*len != sizeof(struct ipt_getinfo))
954 return -EINVAL;
955
956 if (copy_from_user(name, user, sizeof(name)) != 0)
957 return -EFAULT;
958
959 name[XT_TABLE_MAXNAMELEN-1] = '\0';
960#ifdef CONFIG_NETFILTER_XTABLES_COMPAT
961 if (in_compat_syscall())
962 xt_compat_lock(AF_INET);
963#endif
964 t = xt_request_find_table_lock(net, AF_INET, name);
965 if (!IS_ERR(t)) {
966 struct ipt_getinfo info;
967 const struct xt_table_info *private = t->private;
968#ifdef CONFIG_NETFILTER_XTABLES_COMPAT
969 struct xt_table_info tmp;
970
971 if (in_compat_syscall()) {
972 ret = compat_table_info(private, &tmp);
973 xt_compat_flush_offsets(AF_INET);
974 private = &tmp;
975 }
976#endif
977 memset(&info, 0, sizeof(info));
978 info.valid_hooks = t->valid_hooks;
979 memcpy(info.hook_entry, private->hook_entry,
980 sizeof(info.hook_entry));
981 memcpy(info.underflow, private->underflow,
982 sizeof(info.underflow));
983 info.num_entries = private->number;
984 info.size = private->size;
985 strcpy(info.name, name);
986
987 if (copy_to_user(user, &info, *len) != 0)
988 ret = -EFAULT;
989 else
990 ret = 0;
991
992 xt_table_unlock(t);
993 module_put(t->me);
994 } else
995 ret = PTR_ERR(t);
996#ifdef CONFIG_NETFILTER_XTABLES_COMPAT
997 if (in_compat_syscall())
998 xt_compat_unlock(AF_INET);
999#endif
1000 return ret;
1001}
1002
1003static int
1004get_entries(struct net *net, struct ipt_get_entries __user *uptr,
1005 const int *len)
1006{
1007 int ret;
1008 struct ipt_get_entries get;
1009 struct xt_table *t;
1010
1011 if (*len < sizeof(get))
1012 return -EINVAL;
1013 if (copy_from_user(&get, uptr, sizeof(get)) != 0)
1014 return -EFAULT;
1015 if (*len != sizeof(struct ipt_get_entries) + get.size)
1016 return -EINVAL;
1017 get.name[sizeof(get.name) - 1] = '\0';
1018
1019 t = xt_find_table_lock(net, AF_INET, get.name);
1020 if (!IS_ERR(t)) {
1021 const struct xt_table_info *private = t->private;
1022 if (get.size == private->size)
1023 ret = copy_entries_to_user(private->size,
1024 t, uptr->entrytable);
1025 else
1026 ret = -EAGAIN;
1027
1028 module_put(t->me);
1029 xt_table_unlock(t);
1030 } else
1031 ret = PTR_ERR(t);
1032
1033 return ret;
1034}
1035
1036static int
1037__do_replace(struct net *net, const char *name, unsigned int valid_hooks,
1038 struct xt_table_info *newinfo, unsigned int num_counters,
1039 void __user *counters_ptr)
1040{
1041 int ret;
1042 struct xt_table *t;
1043 struct xt_table_info *oldinfo;
1044 struct xt_counters *counters;
1045 struct ipt_entry *iter;
1046
1047 ret = 0;
1048 counters = xt_counters_alloc(num_counters);
1049 if (!counters) {
1050 ret = -ENOMEM;
1051 goto out;
1052 }
1053
1054 t = xt_request_find_table_lock(net, AF_INET, name);
1055 if (IS_ERR(t)) {
1056 ret = PTR_ERR(t);
1057 goto free_newinfo_counters_untrans;
1058 }
1059
1060
1061 if (valid_hooks != t->valid_hooks) {
1062 ret = -EINVAL;
1063 goto put_module;
1064 }
1065
1066 oldinfo = xt_replace_table(t, num_counters, newinfo, &ret);
1067 if (!oldinfo)
1068 goto put_module;
1069
1070
1071 if ((oldinfo->number > oldinfo->initial_entries) ||
1072 (newinfo->number <= oldinfo->initial_entries))
1073 module_put(t->me);
1074 if ((oldinfo->number > oldinfo->initial_entries) &&
1075 (newinfo->number <= oldinfo->initial_entries))
1076 module_put(t->me);
1077
1078 xt_table_unlock(t);
1079
1080 get_old_counters(oldinfo, counters);
1081
1082
1083 xt_entry_foreach(iter, oldinfo->entries, oldinfo->size)
1084 cleanup_entry(iter, net);
1085
1086 xt_free_table_info(oldinfo);
1087 if (copy_to_user(counters_ptr, counters,
1088 sizeof(struct xt_counters) * num_counters) != 0) {
1089
1090 net_warn_ratelimited("iptables: counters copy to user failed while replacing table\n");
1091 }
1092 vfree(counters);
1093 return ret;
1094
1095 put_module:
1096 module_put(t->me);
1097 xt_table_unlock(t);
1098 free_newinfo_counters_untrans:
1099 vfree(counters);
1100 out:
1101 return ret;
1102}
1103
1104static int
1105do_replace(struct net *net, sockptr_t arg, unsigned int len)
1106{
1107 int ret;
1108 struct ipt_replace tmp;
1109 struct xt_table_info *newinfo;
1110 void *loc_cpu_entry;
1111 struct ipt_entry *iter;
1112
1113 if (copy_from_sockptr(&tmp, arg, sizeof(tmp)) != 0)
1114 return -EFAULT;
1115
1116
1117 if (tmp.num_counters >= INT_MAX / sizeof(struct xt_counters))
1118 return -ENOMEM;
1119 if (tmp.num_counters == 0)
1120 return -EINVAL;
1121
1122 tmp.name[sizeof(tmp.name)-1] = 0;
1123
1124 newinfo = xt_alloc_table_info(tmp.size);
1125 if (!newinfo)
1126 return -ENOMEM;
1127
1128 loc_cpu_entry = newinfo->entries;
1129 if (copy_from_sockptr_offset(loc_cpu_entry, arg, sizeof(tmp),
1130 tmp.size) != 0) {
1131 ret = -EFAULT;
1132 goto free_newinfo;
1133 }
1134
1135 ret = translate_table(net, newinfo, loc_cpu_entry, &tmp);
1136 if (ret != 0)
1137 goto free_newinfo;
1138
1139 ret = __do_replace(net, tmp.name, tmp.valid_hooks, newinfo,
1140 tmp.num_counters, tmp.counters);
1141 if (ret)
1142 goto free_newinfo_untrans;
1143 return 0;
1144
1145 free_newinfo_untrans:
1146 xt_entry_foreach(iter, loc_cpu_entry, newinfo->size)
1147 cleanup_entry(iter, net);
1148 free_newinfo:
1149 xt_free_table_info(newinfo);
1150 return ret;
1151}
1152
1153static int
1154do_add_counters(struct net *net, sockptr_t arg, unsigned int len)
1155{
1156 unsigned int i;
1157 struct xt_counters_info tmp;
1158 struct xt_counters *paddc;
1159 struct xt_table *t;
1160 const struct xt_table_info *private;
1161 int ret = 0;
1162 struct ipt_entry *iter;
1163 unsigned int addend;
1164
1165 paddc = xt_copy_counters(arg, len, &tmp);
1166 if (IS_ERR(paddc))
1167 return PTR_ERR(paddc);
1168
1169 t = xt_find_table_lock(net, AF_INET, tmp.name);
1170 if (IS_ERR(t)) {
1171 ret = PTR_ERR(t);
1172 goto free;
1173 }
1174
1175 local_bh_disable();
1176 private = t->private;
1177 if (private->number != tmp.num_counters) {
1178 ret = -EINVAL;
1179 goto unlock_up_free;
1180 }
1181
1182 i = 0;
1183 addend = xt_write_recseq_begin();
1184 xt_entry_foreach(iter, private->entries, private->size) {
1185 struct xt_counters *tmp;
1186
1187 tmp = xt_get_this_cpu_counter(&iter->counters);
1188 ADD_COUNTER(*tmp, paddc[i].bcnt, paddc[i].pcnt);
1189 ++i;
1190 }
1191 xt_write_recseq_end(addend);
1192 unlock_up_free:
1193 local_bh_enable();
1194 xt_table_unlock(t);
1195 module_put(t->me);
1196 free:
1197 vfree(paddc);
1198
1199 return ret;
1200}
1201
1202#ifdef CONFIG_NETFILTER_XTABLES_COMPAT
1203struct compat_ipt_replace {
1204 char name[XT_TABLE_MAXNAMELEN];
1205 u32 valid_hooks;
1206 u32 num_entries;
1207 u32 size;
1208 u32 hook_entry[NF_INET_NUMHOOKS];
1209 u32 underflow[NF_INET_NUMHOOKS];
1210 u32 num_counters;
1211 compat_uptr_t counters;
1212 struct compat_ipt_entry entries[];
1213};
1214
1215static int
1216compat_copy_entry_to_user(struct ipt_entry *e, void __user **dstptr,
1217 unsigned int *size, struct xt_counters *counters,
1218 unsigned int i)
1219{
1220 struct xt_entry_target *t;
1221 struct compat_ipt_entry __user *ce;
1222 u_int16_t target_offset, next_offset;
1223 compat_uint_t origsize;
1224 const struct xt_entry_match *ematch;
1225 int ret = 0;
1226
1227 origsize = *size;
1228 ce = *dstptr;
1229 if (copy_to_user(ce, e, sizeof(struct ipt_entry)) != 0 ||
1230 copy_to_user(&ce->counters, &counters[i],
1231 sizeof(counters[i])) != 0)
1232 return -EFAULT;
1233
1234 *dstptr += sizeof(struct compat_ipt_entry);
1235 *size -= sizeof(struct ipt_entry) - sizeof(struct compat_ipt_entry);
1236
1237 xt_ematch_foreach(ematch, e) {
1238 ret = xt_compat_match_to_user(ematch, dstptr, size);
1239 if (ret != 0)
1240 return ret;
1241 }
1242 target_offset = e->target_offset - (origsize - *size);
1243 t = ipt_get_target(e);
1244 ret = xt_compat_target_to_user(t, dstptr, size);
1245 if (ret)
1246 return ret;
1247 next_offset = e->next_offset - (origsize - *size);
1248 if (put_user(target_offset, &ce->target_offset) != 0 ||
1249 put_user(next_offset, &ce->next_offset) != 0)
1250 return -EFAULT;
1251 return 0;
1252}
1253
1254static int
1255compat_find_calc_match(struct xt_entry_match *m,
1256 const struct ipt_ip *ip,
1257 int *size)
1258{
1259 struct xt_match *match;
1260
1261 match = xt_request_find_match(NFPROTO_IPV4, m->u.user.name,
1262 m->u.user.revision);
1263 if (IS_ERR(match))
1264 return PTR_ERR(match);
1265
1266 m->u.kernel.match = match;
1267 *size += xt_compat_match_offset(match);
1268 return 0;
1269}
1270
1271static void compat_release_entry(struct compat_ipt_entry *e)
1272{
1273 struct xt_entry_target *t;
1274 struct xt_entry_match *ematch;
1275
1276
1277 xt_ematch_foreach(ematch, e)
1278 module_put(ematch->u.kernel.match->me);
1279 t = compat_ipt_get_target(e);
1280 module_put(t->u.kernel.target->me);
1281}
1282
1283static int
1284check_compat_entry_size_and_hooks(struct compat_ipt_entry *e,
1285 struct xt_table_info *newinfo,
1286 unsigned int *size,
1287 const unsigned char *base,
1288 const unsigned char *limit)
1289{
1290 struct xt_entry_match *ematch;
1291 struct xt_entry_target *t;
1292 struct xt_target *target;
1293 unsigned int entry_offset;
1294 unsigned int j;
1295 int ret, off;
1296
1297 if ((unsigned long)e % __alignof__(struct compat_ipt_entry) != 0 ||
1298 (unsigned char *)e + sizeof(struct compat_ipt_entry) >= limit ||
1299 (unsigned char *)e + e->next_offset > limit)
1300 return -EINVAL;
1301
1302 if (e->next_offset < sizeof(struct compat_ipt_entry) +
1303 sizeof(struct compat_xt_entry_target))
1304 return -EINVAL;
1305
1306 if (!ip_checkentry(&e->ip))
1307 return -EINVAL;
1308
1309 ret = xt_compat_check_entry_offsets(e, e->elems,
1310 e->target_offset, e->next_offset);
1311 if (ret)
1312 return ret;
1313
1314 off = sizeof(struct ipt_entry) - sizeof(struct compat_ipt_entry);
1315 entry_offset = (void *)e - (void *)base;
1316 j = 0;
1317 xt_ematch_foreach(ematch, e) {
1318 ret = compat_find_calc_match(ematch, &e->ip, &off);
1319 if (ret != 0)
1320 goto release_matches;
1321 ++j;
1322 }
1323
1324 t = compat_ipt_get_target(e);
1325 target = xt_request_find_target(NFPROTO_IPV4, t->u.user.name,
1326 t->u.user.revision);
1327 if (IS_ERR(target)) {
1328 ret = PTR_ERR(target);
1329 goto release_matches;
1330 }
1331 t->u.kernel.target = target;
1332
1333 off += xt_compat_target_offset(target);
1334 *size += off;
1335 ret = xt_compat_add_offset(AF_INET, entry_offset, off);
1336 if (ret)
1337 goto out;
1338
1339 return 0;
1340
1341out:
1342 module_put(t->u.kernel.target->me);
1343release_matches:
1344 xt_ematch_foreach(ematch, e) {
1345 if (j-- == 0)
1346 break;
1347 module_put(ematch->u.kernel.match->me);
1348 }
1349 return ret;
1350}
1351
1352static void
1353compat_copy_entry_from_user(struct compat_ipt_entry *e, void **dstptr,
1354 unsigned int *size,
1355 struct xt_table_info *newinfo, unsigned char *base)
1356{
1357 struct xt_entry_target *t;
1358 struct ipt_entry *de;
1359 unsigned int origsize;
1360 int h;
1361 struct xt_entry_match *ematch;
1362
1363 origsize = *size;
1364 de = *dstptr;
1365 memcpy(de, e, sizeof(struct ipt_entry));
1366 memcpy(&de->counters, &e->counters, sizeof(e->counters));
1367
1368 *dstptr += sizeof(struct ipt_entry);
1369 *size += sizeof(struct ipt_entry) - sizeof(struct compat_ipt_entry);
1370
1371 xt_ematch_foreach(ematch, e)
1372 xt_compat_match_from_user(ematch, dstptr, size);
1373
1374 de->target_offset = e->target_offset - (origsize - *size);
1375 t = compat_ipt_get_target(e);
1376 xt_compat_target_from_user(t, dstptr, size);
1377
1378 de->next_offset = e->next_offset - (origsize - *size);
1379
1380 for (h = 0; h < NF_INET_NUMHOOKS; h++) {
1381 if ((unsigned char *)de - base < newinfo->hook_entry[h])
1382 newinfo->hook_entry[h] -= origsize - *size;
1383 if ((unsigned char *)de - base < newinfo->underflow[h])
1384 newinfo->underflow[h] -= origsize - *size;
1385 }
1386}
1387
1388static int
1389translate_compat_table(struct net *net,
1390 struct xt_table_info **pinfo,
1391 void **pentry0,
1392 const struct compat_ipt_replace *compatr)
1393{
1394 unsigned int i, j;
1395 struct xt_table_info *newinfo, *info;
1396 void *pos, *entry0, *entry1;
1397 struct compat_ipt_entry *iter0;
1398 struct ipt_replace repl;
1399 unsigned int size;
1400 int ret;
1401
1402 info = *pinfo;
1403 entry0 = *pentry0;
1404 size = compatr->size;
1405 info->number = compatr->num_entries;
1406
1407 j = 0;
1408 xt_compat_lock(AF_INET);
1409 ret = xt_compat_init_offsets(AF_INET, compatr->num_entries);
1410 if (ret)
1411 goto out_unlock;
1412
1413 xt_entry_foreach(iter0, entry0, compatr->size) {
1414 ret = check_compat_entry_size_and_hooks(iter0, info, &size,
1415 entry0,
1416 entry0 + compatr->size);
1417 if (ret != 0)
1418 goto out_unlock;
1419 ++j;
1420 }
1421
1422 ret = -EINVAL;
1423 if (j != compatr->num_entries)
1424 goto out_unlock;
1425
1426 ret = -ENOMEM;
1427 newinfo = xt_alloc_table_info(size);
1428 if (!newinfo)
1429 goto out_unlock;
1430
1431 memset(newinfo->entries, 0, size);
1432
1433 newinfo->number = compatr->num_entries;
1434 for (i = 0; i < NF_INET_NUMHOOKS; i++) {
1435 newinfo->hook_entry[i] = compatr->hook_entry[i];
1436 newinfo->underflow[i] = compatr->underflow[i];
1437 }
1438 entry1 = newinfo->entries;
1439 pos = entry1;
1440 size = compatr->size;
1441 xt_entry_foreach(iter0, entry0, compatr->size)
1442 compat_copy_entry_from_user(iter0, &pos, &size,
1443 newinfo, entry1);
1444
1445
1446
1447
1448
1449
1450
1451
1452 xt_compat_flush_offsets(AF_INET);
1453 xt_compat_unlock(AF_INET);
1454
1455 memcpy(&repl, compatr, sizeof(*compatr));
1456
1457 for (i = 0; i < NF_INET_NUMHOOKS; i++) {
1458 repl.hook_entry[i] = newinfo->hook_entry[i];
1459 repl.underflow[i] = newinfo->underflow[i];
1460 }
1461
1462 repl.num_counters = 0;
1463 repl.counters = NULL;
1464 repl.size = newinfo->size;
1465 ret = translate_table(net, newinfo, entry1, &repl);
1466 if (ret)
1467 goto free_newinfo;
1468
1469 *pinfo = newinfo;
1470 *pentry0 = entry1;
1471 xt_free_table_info(info);
1472 return 0;
1473
1474free_newinfo:
1475 xt_free_table_info(newinfo);
1476 return ret;
1477out_unlock:
1478 xt_compat_flush_offsets(AF_INET);
1479 xt_compat_unlock(AF_INET);
1480 xt_entry_foreach(iter0, entry0, compatr->size) {
1481 if (j-- == 0)
1482 break;
1483 compat_release_entry(iter0);
1484 }
1485 return ret;
1486}
1487
1488static int
1489compat_do_replace(struct net *net, sockptr_t arg, unsigned int len)
1490{
1491 int ret;
1492 struct compat_ipt_replace tmp;
1493 struct xt_table_info *newinfo;
1494 void *loc_cpu_entry;
1495 struct ipt_entry *iter;
1496
1497 if (copy_from_sockptr(&tmp, arg, sizeof(tmp)) != 0)
1498 return -EFAULT;
1499
1500
1501 if (tmp.num_counters >= INT_MAX / sizeof(struct xt_counters))
1502 return -ENOMEM;
1503 if (tmp.num_counters == 0)
1504 return -EINVAL;
1505
1506 tmp.name[sizeof(tmp.name)-1] = 0;
1507
1508 newinfo = xt_alloc_table_info(tmp.size);
1509 if (!newinfo)
1510 return -ENOMEM;
1511
1512 loc_cpu_entry = newinfo->entries;
1513 if (copy_from_sockptr_offset(loc_cpu_entry, arg, sizeof(tmp),
1514 tmp.size) != 0) {
1515 ret = -EFAULT;
1516 goto free_newinfo;
1517 }
1518
1519 ret = translate_compat_table(net, &newinfo, &loc_cpu_entry, &tmp);
1520 if (ret != 0)
1521 goto free_newinfo;
1522
1523 ret = __do_replace(net, tmp.name, tmp.valid_hooks, newinfo,
1524 tmp.num_counters, compat_ptr(tmp.counters));
1525 if (ret)
1526 goto free_newinfo_untrans;
1527 return 0;
1528
1529 free_newinfo_untrans:
1530 xt_entry_foreach(iter, loc_cpu_entry, newinfo->size)
1531 cleanup_entry(iter, net);
1532 free_newinfo:
1533 xt_free_table_info(newinfo);
1534 return ret;
1535}
1536
1537struct compat_ipt_get_entries {
1538 char name[XT_TABLE_MAXNAMELEN];
1539 compat_uint_t size;
1540 struct compat_ipt_entry entrytable[];
1541};
1542
1543static int
1544compat_copy_entries_to_user(unsigned int total_size, struct xt_table *table,
1545 void __user *userptr)
1546{
1547 struct xt_counters *counters;
1548 const struct xt_table_info *private = table->private;
1549 void __user *pos;
1550 unsigned int size;
1551 int ret = 0;
1552 unsigned int i = 0;
1553 struct ipt_entry *iter;
1554
1555 counters = alloc_counters(table);
1556 if (IS_ERR(counters))
1557 return PTR_ERR(counters);
1558
1559 pos = userptr;
1560 size = total_size;
1561 xt_entry_foreach(iter, private->entries, total_size) {
1562 ret = compat_copy_entry_to_user(iter, &pos,
1563 &size, counters, i++);
1564 if (ret != 0)
1565 break;
1566 }
1567
1568 vfree(counters);
1569 return ret;
1570}
1571
1572static int
1573compat_get_entries(struct net *net, struct compat_ipt_get_entries __user *uptr,
1574 int *len)
1575{
1576 int ret;
1577 struct compat_ipt_get_entries get;
1578 struct xt_table *t;
1579
1580 if (*len < sizeof(get))
1581 return -EINVAL;
1582
1583 if (copy_from_user(&get, uptr, sizeof(get)) != 0)
1584 return -EFAULT;
1585
1586 if (*len != sizeof(struct compat_ipt_get_entries) + get.size)
1587 return -EINVAL;
1588
1589 get.name[sizeof(get.name) - 1] = '\0';
1590
1591 xt_compat_lock(AF_INET);
1592 t = xt_find_table_lock(net, AF_INET, get.name);
1593 if (!IS_ERR(t)) {
1594 const struct xt_table_info *private = t->private;
1595 struct xt_table_info info;
1596 ret = compat_table_info(private, &info);
1597 if (!ret && get.size == info.size)
1598 ret = compat_copy_entries_to_user(private->size,
1599 t, uptr->entrytable);
1600 else if (!ret)
1601 ret = -EAGAIN;
1602
1603 xt_compat_flush_offsets(AF_INET);
1604 module_put(t->me);
1605 xt_table_unlock(t);
1606 } else
1607 ret = PTR_ERR(t);
1608
1609 xt_compat_unlock(AF_INET);
1610 return ret;
1611}
1612#endif
1613
1614static int
1615do_ipt_set_ctl(struct sock *sk, int cmd, sockptr_t arg, unsigned int len)
1616{
1617 int ret;
1618
1619 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
1620 return -EPERM;
1621
1622 switch (cmd) {
1623 case IPT_SO_SET_REPLACE:
1624#ifdef CONFIG_NETFILTER_XTABLES_COMPAT
1625 if (in_compat_syscall())
1626 ret = compat_do_replace(sock_net(sk), arg, len);
1627 else
1628#endif
1629 ret = do_replace(sock_net(sk), arg, len);
1630 break;
1631
1632 case IPT_SO_SET_ADD_COUNTERS:
1633 ret = do_add_counters(sock_net(sk), arg, len);
1634 break;
1635
1636 default:
1637 ret = -EINVAL;
1638 }
1639
1640 return ret;
1641}
1642
1643static int
1644do_ipt_get_ctl(struct sock *sk, int cmd, void __user *user, int *len)
1645{
1646 int ret;
1647
1648 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
1649 return -EPERM;
1650
1651 switch (cmd) {
1652 case IPT_SO_GET_INFO:
1653 ret = get_info(sock_net(sk), user, len);
1654 break;
1655
1656 case IPT_SO_GET_ENTRIES:
1657#ifdef CONFIG_NETFILTER_XTABLES_COMPAT
1658 if (in_compat_syscall())
1659 ret = compat_get_entries(sock_net(sk), user, len);
1660 else
1661#endif
1662 ret = get_entries(sock_net(sk), user, len);
1663 break;
1664
1665 case IPT_SO_GET_REVISION_MATCH:
1666 case IPT_SO_GET_REVISION_TARGET: {
1667 struct xt_get_revision rev;
1668 int target;
1669
1670 if (*len != sizeof(rev)) {
1671 ret = -EINVAL;
1672 break;
1673 }
1674 if (copy_from_user(&rev, user, sizeof(rev)) != 0) {
1675 ret = -EFAULT;
1676 break;
1677 }
1678 rev.name[sizeof(rev.name)-1] = 0;
1679
1680 if (cmd == IPT_SO_GET_REVISION_TARGET)
1681 target = 1;
1682 else
1683 target = 0;
1684
1685 try_then_request_module(xt_find_revision(AF_INET, rev.name,
1686 rev.revision,
1687 target, &ret),
1688 "ipt_%s", rev.name);
1689 break;
1690 }
1691
1692 default:
1693 ret = -EINVAL;
1694 }
1695
1696 return ret;
1697}
1698
1699static void __ipt_unregister_table(struct net *net, struct xt_table *table)
1700{
1701 struct xt_table_info *private;
1702 void *loc_cpu_entry;
1703 struct module *table_owner = table->me;
1704 struct ipt_entry *iter;
1705
1706 private = xt_unregister_table(table);
1707
1708
1709 loc_cpu_entry = private->entries;
1710 xt_entry_foreach(iter, loc_cpu_entry, private->size)
1711 cleanup_entry(iter, net);
1712 if (private->number > private->initial_entries)
1713 module_put(table_owner);
1714 xt_free_table_info(private);
1715}
1716
1717int ipt_register_table(struct net *net, const struct xt_table *table,
1718 const struct ipt_replace *repl,
1719 const struct nf_hook_ops *template_ops)
1720{
1721 struct nf_hook_ops *ops;
1722 unsigned int num_ops;
1723 int ret, i;
1724 struct xt_table_info *newinfo;
1725 struct xt_table_info bootstrap = {0};
1726 void *loc_cpu_entry;
1727 struct xt_table *new_table;
1728
1729 newinfo = xt_alloc_table_info(repl->size);
1730 if (!newinfo)
1731 return -ENOMEM;
1732
1733 loc_cpu_entry = newinfo->entries;
1734 memcpy(loc_cpu_entry, repl->entries, repl->size);
1735
1736 ret = translate_table(net, newinfo, loc_cpu_entry, repl);
1737 if (ret != 0) {
1738 xt_free_table_info(newinfo);
1739 return ret;
1740 }
1741
1742 new_table = xt_register_table(net, table, &bootstrap, newinfo);
1743 if (IS_ERR(new_table)) {
1744 xt_free_table_info(newinfo);
1745 return PTR_ERR(new_table);
1746 }
1747
1748
1749
1750
1751 if (!template_ops)
1752 return 0;
1753
1754 num_ops = hweight32(table->valid_hooks);
1755 if (num_ops == 0) {
1756 ret = -EINVAL;
1757 goto out_free;
1758 }
1759
1760 ops = kmemdup(template_ops, sizeof(*ops) * num_ops, GFP_KERNEL);
1761 if (!ops) {
1762 ret = -ENOMEM;
1763 goto out_free;
1764 }
1765
1766 for (i = 0; i < num_ops; i++)
1767 ops[i].priv = new_table;
1768
1769 new_table->ops = ops;
1770
1771 ret = nf_register_net_hooks(net, ops, num_ops);
1772 if (ret != 0)
1773 goto out_free;
1774
1775 return ret;
1776
1777out_free:
1778 __ipt_unregister_table(net, new_table);
1779 return ret;
1780}
1781
1782void ipt_unregister_table_pre_exit(struct net *net, const char *name)
1783{
1784 struct xt_table *table = xt_find_table(net, NFPROTO_IPV4, name);
1785
1786 if (table)
1787 nf_unregister_net_hooks(net, table->ops, hweight32(table->valid_hooks));
1788}
1789
1790void ipt_unregister_table_exit(struct net *net, const char *name)
1791{
1792 struct xt_table *table = xt_find_table(net, NFPROTO_IPV4, name);
1793
1794 if (table)
1795 __ipt_unregister_table(net, table);
1796}
1797
1798
1799static inline bool
1800icmp_type_code_match(u_int8_t test_type, u_int8_t min_code, u_int8_t max_code,
1801 u_int8_t type, u_int8_t code,
1802 bool invert)
1803{
1804 return ((test_type == 0xFF) ||
1805 (type == test_type && code >= min_code && code <= max_code))
1806 ^ invert;
1807}
1808
1809static bool
1810icmp_match(const struct sk_buff *skb, struct xt_action_param *par)
1811{
1812 const struct icmphdr *ic;
1813 struct icmphdr _icmph;
1814 const struct ipt_icmp *icmpinfo = par->matchinfo;
1815
1816
1817 if (par->fragoff != 0)
1818 return false;
1819
1820 ic = skb_header_pointer(skb, par->thoff, sizeof(_icmph), &_icmph);
1821 if (ic == NULL) {
1822
1823
1824
1825 par->hotdrop = true;
1826 return false;
1827 }
1828
1829 return icmp_type_code_match(icmpinfo->type,
1830 icmpinfo->code[0],
1831 icmpinfo->code[1],
1832 ic->type, ic->code,
1833 !!(icmpinfo->invflags&IPT_ICMP_INV));
1834}
1835
1836static int icmp_checkentry(const struct xt_mtchk_param *par)
1837{
1838 const struct ipt_icmp *icmpinfo = par->matchinfo;
1839
1840
1841 return (icmpinfo->invflags & ~IPT_ICMP_INV) ? -EINVAL : 0;
1842}
1843
1844static struct xt_target ipt_builtin_tg[] __read_mostly = {
1845 {
1846 .name = XT_STANDARD_TARGET,
1847 .targetsize = sizeof(int),
1848 .family = NFPROTO_IPV4,
1849#ifdef CONFIG_NETFILTER_XTABLES_COMPAT
1850 .compatsize = sizeof(compat_int_t),
1851 .compat_from_user = compat_standard_from_user,
1852 .compat_to_user = compat_standard_to_user,
1853#endif
1854 },
1855 {
1856 .name = XT_ERROR_TARGET,
1857 .target = ipt_error,
1858 .targetsize = XT_FUNCTION_MAXNAMELEN,
1859 .family = NFPROTO_IPV4,
1860 },
1861};
1862
1863static struct nf_sockopt_ops ipt_sockopts = {
1864 .pf = PF_INET,
1865 .set_optmin = IPT_BASE_CTL,
1866 .set_optmax = IPT_SO_SET_MAX+1,
1867 .set = do_ipt_set_ctl,
1868 .get_optmin = IPT_BASE_CTL,
1869 .get_optmax = IPT_SO_GET_MAX+1,
1870 .get = do_ipt_get_ctl,
1871 .owner = THIS_MODULE,
1872};
1873
1874static struct xt_match ipt_builtin_mt[] __read_mostly = {
1875 {
1876 .name = "icmp",
1877 .match = icmp_match,
1878 .matchsize = sizeof(struct ipt_icmp),
1879 .checkentry = icmp_checkentry,
1880 .proto = IPPROTO_ICMP,
1881 .family = NFPROTO_IPV4,
1882 .me = THIS_MODULE,
1883 },
1884};
1885
1886static int __net_init ip_tables_net_init(struct net *net)
1887{
1888 return xt_proto_init(net, NFPROTO_IPV4);
1889}
1890
1891static void __net_exit ip_tables_net_exit(struct net *net)
1892{
1893 xt_proto_fini(net, NFPROTO_IPV4);
1894}
1895
1896static struct pernet_operations ip_tables_net_ops = {
1897 .init = ip_tables_net_init,
1898 .exit = ip_tables_net_exit,
1899};
1900
1901static int __init ip_tables_init(void)
1902{
1903 int ret;
1904
1905 ret = register_pernet_subsys(&ip_tables_net_ops);
1906 if (ret < 0)
1907 goto err1;
1908
1909
1910 ret = xt_register_targets(ipt_builtin_tg, ARRAY_SIZE(ipt_builtin_tg));
1911 if (ret < 0)
1912 goto err2;
1913 ret = xt_register_matches(ipt_builtin_mt, ARRAY_SIZE(ipt_builtin_mt));
1914 if (ret < 0)
1915 goto err4;
1916
1917
1918 ret = nf_register_sockopt(&ipt_sockopts);
1919 if (ret < 0)
1920 goto err5;
1921
1922 return 0;
1923
1924err5:
1925 xt_unregister_matches(ipt_builtin_mt, ARRAY_SIZE(ipt_builtin_mt));
1926err4:
1927 xt_unregister_targets(ipt_builtin_tg, ARRAY_SIZE(ipt_builtin_tg));
1928err2:
1929 unregister_pernet_subsys(&ip_tables_net_ops);
1930err1:
1931 return ret;
1932}
1933
1934static void __exit ip_tables_fini(void)
1935{
1936 nf_unregister_sockopt(&ipt_sockopts);
1937
1938 xt_unregister_matches(ipt_builtin_mt, ARRAY_SIZE(ipt_builtin_mt));
1939 xt_unregister_targets(ipt_builtin_tg, ARRAY_SIZE(ipt_builtin_tg));
1940 unregister_pernet_subsys(&ip_tables_net_ops);
1941}
1942
1943EXPORT_SYMBOL(ipt_register_table);
1944EXPORT_SYMBOL(ipt_unregister_table_pre_exit);
1945EXPORT_SYMBOL(ipt_unregister_table_exit);
1946EXPORT_SYMBOL(ipt_do_table);
1947module_init(ip_tables_init);
1948module_exit(ip_tables_fini);
1949
