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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_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,
948 const int *len, int compat)
949{
950 char name[XT_TABLE_MAXNAMELEN];
951 struct xt_table *t;
952 int ret;
953
954 if (*len != sizeof(struct ipt_getinfo))
955 return -EINVAL;
956
957 if (copy_from_user(name, user, sizeof(name)) != 0)
958 return -EFAULT;
959
960 name[XT_TABLE_MAXNAMELEN-1] = '\0';
961#ifdef CONFIG_COMPAT
962 if (compat)
963 xt_compat_lock(AF_INET);
964#endif
965 t = xt_request_find_table_lock(net, AF_INET, name);
966 if (!IS_ERR(t)) {
967 struct ipt_getinfo info;
968 const struct xt_table_info *private = t->private;
969#ifdef CONFIG_COMPAT
970 struct xt_table_info tmp;
971
972 if (compat) {
973 ret = compat_table_info(private, &tmp);
974 xt_compat_flush_offsets(AF_INET);
975 private = &tmp;
976 }
977#endif
978 memset(&info, 0, sizeof(info));
979 info.valid_hooks = t->valid_hooks;
980 memcpy(info.hook_entry, private->hook_entry,
981 sizeof(info.hook_entry));
982 memcpy(info.underflow, private->underflow,
983 sizeof(info.underflow));
984 info.num_entries = private->number;
985 info.size = private->size;
986 strcpy(info.name, name);
987
988 if (copy_to_user(user, &info, *len) != 0)
989 ret = -EFAULT;
990 else
991 ret = 0;
992
993 xt_table_unlock(t);
994 module_put(t->me);
995 } else
996 ret = PTR_ERR(t);
997#ifdef CONFIG_COMPAT
998 if (compat)
999 xt_compat_unlock(AF_INET);
1000#endif
1001 return ret;
1002}
1003
1004static int
1005get_entries(struct net *net, struct ipt_get_entries __user *uptr,
1006 const int *len)
1007{
1008 int ret;
1009 struct ipt_get_entries get;
1010 struct xt_table *t;
1011
1012 if (*len < sizeof(get))
1013 return -EINVAL;
1014 if (copy_from_user(&get, uptr, sizeof(get)) != 0)
1015 return -EFAULT;
1016 if (*len != sizeof(struct ipt_get_entries) + get.size)
1017 return -EINVAL;
1018 get.name[sizeof(get.name) - 1] = '\0';
1019
1020 t = xt_find_table_lock(net, AF_INET, get.name);
1021 if (!IS_ERR(t)) {
1022 const struct xt_table_info *private = t->private;
1023 if (get.size == private->size)
1024 ret = copy_entries_to_user(private->size,
1025 t, uptr->entrytable);
1026 else
1027 ret = -EAGAIN;
1028
1029 module_put(t->me);
1030 xt_table_unlock(t);
1031 } else
1032 ret = PTR_ERR(t);
1033
1034 return ret;
1035}
1036
1037static int
1038__do_replace(struct net *net, const char *name, unsigned int valid_hooks,
1039 struct xt_table_info *newinfo, unsigned int num_counters,
1040 void __user *counters_ptr)
1041{
1042 int ret;
1043 struct xt_table *t;
1044 struct xt_table_info *oldinfo;
1045 struct xt_counters *counters;
1046 struct ipt_entry *iter;
1047
1048 ret = 0;
1049 counters = xt_counters_alloc(num_counters);
1050 if (!counters) {
1051 ret = -ENOMEM;
1052 goto out;
1053 }
1054
1055 t = xt_request_find_table_lock(net, AF_INET, name);
1056 if (IS_ERR(t)) {
1057 ret = PTR_ERR(t);
1058 goto free_newinfo_counters_untrans;
1059 }
1060
1061
1062 if (valid_hooks != t->valid_hooks) {
1063 ret = -EINVAL;
1064 goto put_module;
1065 }
1066
1067 oldinfo = xt_replace_table(t, num_counters, newinfo, &ret);
1068 if (!oldinfo)
1069 goto put_module;
1070
1071
1072 if ((oldinfo->number > oldinfo->initial_entries) ||
1073 (newinfo->number <= oldinfo->initial_entries))
1074 module_put(t->me);
1075 if ((oldinfo->number > oldinfo->initial_entries) &&
1076 (newinfo->number <= oldinfo->initial_entries))
1077 module_put(t->me);
1078
1079 xt_table_unlock(t);
1080
1081 get_old_counters(oldinfo, counters);
1082
1083
1084 xt_entry_foreach(iter, oldinfo->entries, oldinfo->size)
1085 cleanup_entry(iter, net);
1086
1087 xt_free_table_info(oldinfo);
1088 if (copy_to_user(counters_ptr, counters,
1089 sizeof(struct xt_counters) * num_counters) != 0) {
1090
1091 net_warn_ratelimited("iptables: counters copy to user failed while replacing table\n");
1092 }
1093 vfree(counters);
1094 return ret;
1095
1096 put_module:
1097 module_put(t->me);
1098 xt_table_unlock(t);
1099 free_newinfo_counters_untrans:
1100 vfree(counters);
1101 out:
1102 return ret;
1103}
1104
1105static int
1106do_replace(struct net *net, const void __user *user, unsigned int len)
1107{
1108 int ret;
1109 struct ipt_replace tmp;
1110 struct xt_table_info *newinfo;
1111 void *loc_cpu_entry;
1112 struct ipt_entry *iter;
1113
1114 if (copy_from_user(&tmp, user, sizeof(tmp)) != 0)
1115 return -EFAULT;
1116
1117
1118 if (tmp.num_counters >= INT_MAX / sizeof(struct xt_counters))
1119 return -ENOMEM;
1120 if (tmp.num_counters == 0)
1121 return -EINVAL;
1122
1123 tmp.name[sizeof(tmp.name)-1] = 0;
1124
1125 newinfo = xt_alloc_table_info(tmp.size);
1126 if (!newinfo)
1127 return -ENOMEM;
1128
1129 loc_cpu_entry = newinfo->entries;
1130 if (copy_from_user(loc_cpu_entry, user + sizeof(tmp),
1131 tmp.size) != 0) {
1132 ret = -EFAULT;
1133 goto free_newinfo;
1134 }
1135
1136 ret = translate_table(net, newinfo, loc_cpu_entry, &tmp);
1137 if (ret != 0)
1138 goto free_newinfo;
1139
1140 ret = __do_replace(net, tmp.name, tmp.valid_hooks, newinfo,
1141 tmp.num_counters, tmp.counters);
1142 if (ret)
1143 goto free_newinfo_untrans;
1144 return 0;
1145
1146 free_newinfo_untrans:
1147 xt_entry_foreach(iter, loc_cpu_entry, newinfo->size)
1148 cleanup_entry(iter, net);
1149 free_newinfo:
1150 xt_free_table_info(newinfo);
1151 return ret;
1152}
1153
1154static int
1155do_add_counters(struct net *net, const void __user *user,
1156 unsigned int len, int compat)
1157{
1158 unsigned int i;
1159 struct xt_counters_info tmp;
1160 struct xt_counters *paddc;
1161 struct xt_table *t;
1162 const struct xt_table_info *private;
1163 int ret = 0;
1164 struct ipt_entry *iter;
1165 unsigned int addend;
1166
1167 paddc = xt_copy_counters_from_user(user, len, &tmp, compat);
1168 if (IS_ERR(paddc))
1169 return PTR_ERR(paddc);
1170
1171 t = xt_find_table_lock(net, AF_INET, tmp.name);
1172 if (IS_ERR(t)) {
1173 ret = PTR_ERR(t);
1174 goto free;
1175 }
1176
1177 local_bh_disable();
1178 private = t->private;
1179 if (private->number != tmp.num_counters) {
1180 ret = -EINVAL;
1181 goto unlock_up_free;
1182 }
1183
1184 i = 0;
1185 addend = xt_write_recseq_begin();
1186 xt_entry_foreach(iter, private->entries, private->size) {
1187 struct xt_counters *tmp;
1188
1189 tmp = xt_get_this_cpu_counter(&iter->counters);
1190 ADD_COUNTER(*tmp, paddc[i].bcnt, paddc[i].pcnt);
1191 ++i;
1192 }
1193 xt_write_recseq_end(addend);
1194 unlock_up_free:
1195 local_bh_enable();
1196 xt_table_unlock(t);
1197 module_put(t->me);
1198 free:
1199 vfree(paddc);
1200
1201 return ret;
1202}
1203
1204#ifdef CONFIG_COMPAT
1205struct compat_ipt_replace {
1206 char name[XT_TABLE_MAXNAMELEN];
1207 u32 valid_hooks;
1208 u32 num_entries;
1209 u32 size;
1210 u32 hook_entry[NF_INET_NUMHOOKS];
1211 u32 underflow[NF_INET_NUMHOOKS];
1212 u32 num_counters;
1213 compat_uptr_t counters;
1214 struct compat_ipt_entry entries[0];
1215};
1216
1217static int
1218compat_copy_entry_to_user(struct ipt_entry *e, void __user **dstptr,
1219 unsigned int *size, struct xt_counters *counters,
1220 unsigned int i)
1221{
1222 struct xt_entry_target *t;
1223 struct compat_ipt_entry __user *ce;
1224 u_int16_t target_offset, next_offset;
1225 compat_uint_t origsize;
1226 const struct xt_entry_match *ematch;
1227 int ret = 0;
1228
1229 origsize = *size;
1230 ce = *dstptr;
1231 if (copy_to_user(ce, e, sizeof(struct ipt_entry)) != 0 ||
1232 copy_to_user(&ce->counters, &counters[i],
1233 sizeof(counters[i])) != 0)
1234 return -EFAULT;
1235
1236 *dstptr += sizeof(struct compat_ipt_entry);
1237 *size -= sizeof(struct ipt_entry) - sizeof(struct compat_ipt_entry);
1238
1239 xt_ematch_foreach(ematch, e) {
1240 ret = xt_compat_match_to_user(ematch, dstptr, size);
1241 if (ret != 0)
1242 return ret;
1243 }
1244 target_offset = e->target_offset - (origsize - *size);
1245 t = ipt_get_target(e);
1246 ret = xt_compat_target_to_user(t, dstptr, size);
1247 if (ret)
1248 return ret;
1249 next_offset = e->next_offset - (origsize - *size);
1250 if (put_user(target_offset, &ce->target_offset) != 0 ||
1251 put_user(next_offset, &ce->next_offset) != 0)
1252 return -EFAULT;
1253 return 0;
1254}
1255
1256static int
1257compat_find_calc_match(struct xt_entry_match *m,
1258 const struct ipt_ip *ip,
1259 int *size)
1260{
1261 struct xt_match *match;
1262
1263 match = xt_request_find_match(NFPROTO_IPV4, m->u.user.name,
1264 m->u.user.revision);
1265 if (IS_ERR(match))
1266 return PTR_ERR(match);
1267
1268 m->u.kernel.match = match;
1269 *size += xt_compat_match_offset(match);
1270 return 0;
1271}
1272
1273static void compat_release_entry(struct compat_ipt_entry *e)
1274{
1275 struct xt_entry_target *t;
1276 struct xt_entry_match *ematch;
1277
1278
1279 xt_ematch_foreach(ematch, e)
1280 module_put(ematch->u.kernel.match->me);
1281 t = compat_ipt_get_target(e);
1282 module_put(t->u.kernel.target->me);
1283}
1284
1285static int
1286check_compat_entry_size_and_hooks(struct compat_ipt_entry *e,
1287 struct xt_table_info *newinfo,
1288 unsigned int *size,
1289 const unsigned char *base,
1290 const unsigned char *limit)
1291{
1292 struct xt_entry_match *ematch;
1293 struct xt_entry_target *t;
1294 struct xt_target *target;
1295 unsigned int entry_offset;
1296 unsigned int j;
1297 int ret, off;
1298
1299 if ((unsigned long)e % __alignof__(struct compat_ipt_entry) != 0 ||
1300 (unsigned char *)e + sizeof(struct compat_ipt_entry) >= limit ||
1301 (unsigned char *)e + e->next_offset > limit)
1302 return -EINVAL;
1303
1304 if (e->next_offset < sizeof(struct compat_ipt_entry) +
1305 sizeof(struct compat_xt_entry_target))
1306 return -EINVAL;
1307
1308 if (!ip_checkentry(&e->ip))
1309 return -EINVAL;
1310
1311 ret = xt_compat_check_entry_offsets(e, e->elems,
1312 e->target_offset, e->next_offset);
1313 if (ret)
1314 return ret;
1315
1316 off = sizeof(struct ipt_entry) - sizeof(struct compat_ipt_entry);
1317 entry_offset = (void *)e - (void *)base;
1318 j = 0;
1319 xt_ematch_foreach(ematch, e) {
1320 ret = compat_find_calc_match(ematch, &e->ip, &off);
1321 if (ret != 0)
1322 goto release_matches;
1323 ++j;
1324 }
1325
1326 t = compat_ipt_get_target(e);
1327 target = xt_request_find_target(NFPROTO_IPV4, t->u.user.name,
1328 t->u.user.revision);
1329 if (IS_ERR(target)) {
1330 ret = PTR_ERR(target);
1331 goto release_matches;
1332 }
1333 t->u.kernel.target = target;
1334
1335 off += xt_compat_target_offset(target);
1336 *size += off;
1337 ret = xt_compat_add_offset(AF_INET, entry_offset, off);
1338 if (ret)
1339 goto out;
1340
1341 return 0;
1342
1343out:
1344 module_put(t->u.kernel.target->me);
1345release_matches:
1346 xt_ematch_foreach(ematch, e) {
1347 if (j-- == 0)
1348 break;
1349 module_put(ematch->u.kernel.match->me);
1350 }
1351 return ret;
1352}
1353
1354static void
1355compat_copy_entry_from_user(struct compat_ipt_entry *e, void **dstptr,
1356 unsigned int *size,
1357 struct xt_table_info *newinfo, unsigned char *base)
1358{
1359 struct xt_entry_target *t;
1360 struct ipt_entry *de;
1361 unsigned int origsize;
1362 int h;
1363 struct xt_entry_match *ematch;
1364
1365 origsize = *size;
1366 de = *dstptr;
1367 memcpy(de, e, sizeof(struct ipt_entry));
1368 memcpy(&de->counters, &e->counters, sizeof(e->counters));
1369
1370 *dstptr += sizeof(struct ipt_entry);
1371 *size += sizeof(struct ipt_entry) - sizeof(struct compat_ipt_entry);
1372
1373 xt_ematch_foreach(ematch, e)
1374 xt_compat_match_from_user(ematch, dstptr, size);
1375
1376 de->target_offset = e->target_offset - (origsize - *size);
1377 t = compat_ipt_get_target(e);
1378 xt_compat_target_from_user(t, dstptr, size);
1379
1380 de->next_offset = e->next_offset - (origsize - *size);
1381
1382 for (h = 0; h < NF_INET_NUMHOOKS; h++) {
1383 if ((unsigned char *)de - base < newinfo->hook_entry[h])
1384 newinfo->hook_entry[h] -= origsize - *size;
1385 if ((unsigned char *)de - base < newinfo->underflow[h])
1386 newinfo->underflow[h] -= origsize - *size;
1387 }
1388}
1389
1390static int
1391translate_compat_table(struct net *net,
1392 struct xt_table_info **pinfo,
1393 void **pentry0,
1394 const struct compat_ipt_replace *compatr)
1395{
1396 unsigned int i, j;
1397 struct xt_table_info *newinfo, *info;
1398 void *pos, *entry0, *entry1;
1399 struct compat_ipt_entry *iter0;
1400 struct ipt_replace repl;
1401 unsigned int size;
1402 int ret;
1403
1404 info = *pinfo;
1405 entry0 = *pentry0;
1406 size = compatr->size;
1407 info->number = compatr->num_entries;
1408
1409 j = 0;
1410 xt_compat_lock(AF_INET);
1411 ret = xt_compat_init_offsets(AF_INET, compatr->num_entries);
1412 if (ret)
1413 goto out_unlock;
1414
1415 xt_entry_foreach(iter0, entry0, compatr->size) {
1416 ret = check_compat_entry_size_and_hooks(iter0, info, &size,
1417 entry0,
1418 entry0 + compatr->size);
1419 if (ret != 0)
1420 goto out_unlock;
1421 ++j;
1422 }
1423
1424 ret = -EINVAL;
1425 if (j != compatr->num_entries)
1426 goto out_unlock;
1427
1428 ret = -ENOMEM;
1429 newinfo = xt_alloc_table_info(size);
1430 if (!newinfo)
1431 goto out_unlock;
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, void __user *user, 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_user(&tmp, user, 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_user(loc_cpu_entry, user + 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
1537static int
1538compat_do_ipt_set_ctl(struct sock *sk, int cmd, void __user *user,
1539 unsigned int len)
1540{
1541 int ret;
1542
1543 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
1544 return -EPERM;
1545
1546 switch (cmd) {
1547 case IPT_SO_SET_REPLACE:
1548 ret = compat_do_replace(sock_net(sk), user, len);
1549 break;
1550
1551 case IPT_SO_SET_ADD_COUNTERS:
1552 ret = do_add_counters(sock_net(sk), user, len, 1);
1553 break;
1554
1555 default:
1556 ret = -EINVAL;
1557 }
1558
1559 return ret;
1560}
1561
1562struct compat_ipt_get_entries {
1563 char name[XT_TABLE_MAXNAMELEN];
1564 compat_uint_t size;
1565 struct compat_ipt_entry entrytable[0];
1566};
1567
1568static int
1569compat_copy_entries_to_user(unsigned int total_size, struct xt_table *table,
1570 void __user *userptr)
1571{
1572 struct xt_counters *counters;
1573 const struct xt_table_info *private = table->private;
1574 void __user *pos;
1575 unsigned int size;
1576 int ret = 0;
1577 unsigned int i = 0;
1578 struct ipt_entry *iter;
1579
1580 counters = alloc_counters(table);
1581 if (IS_ERR(counters))
1582 return PTR_ERR(counters);
1583
1584 pos = userptr;
1585 size = total_size;
1586 xt_entry_foreach(iter, private->entries, total_size) {
1587 ret = compat_copy_entry_to_user(iter, &pos,
1588 &size, counters, i++);
1589 if (ret != 0)
1590 break;
1591 }
1592
1593 vfree(counters);
1594 return ret;
1595}
1596
1597static int
1598compat_get_entries(struct net *net, struct compat_ipt_get_entries __user *uptr,
1599 int *len)
1600{
1601 int ret;
1602 struct compat_ipt_get_entries get;
1603 struct xt_table *t;
1604
1605 if (*len < sizeof(get))
1606 return -EINVAL;
1607
1608 if (copy_from_user(&get, uptr, sizeof(get)) != 0)
1609 return -EFAULT;
1610
1611 if (*len != sizeof(struct compat_ipt_get_entries) + get.size)
1612 return -EINVAL;
1613
1614 get.name[sizeof(get.name) - 1] = '\0';
1615
1616 xt_compat_lock(AF_INET);
1617 t = xt_find_table_lock(net, AF_INET, get.name);
1618 if (!IS_ERR(t)) {
1619 const struct xt_table_info *private = t->private;
1620 struct xt_table_info info;
1621 ret = compat_table_info(private, &info);
1622 if (!ret && get.size == info.size)
1623 ret = compat_copy_entries_to_user(private->size,
1624 t, uptr->entrytable);
1625 else if (!ret)
1626 ret = -EAGAIN;
1627
1628 xt_compat_flush_offsets(AF_INET);
1629 module_put(t->me);
1630 xt_table_unlock(t);
1631 } else
1632 ret = PTR_ERR(t);
1633
1634 xt_compat_unlock(AF_INET);
1635 return ret;
1636}
1637
1638static int do_ipt_get_ctl(struct sock *, int, void __user *, int *);
1639
1640static int
1641compat_do_ipt_get_ctl(struct sock *sk, int cmd, void __user *user, int *len)
1642{
1643 int ret;
1644
1645 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
1646 return -EPERM;
1647
1648 switch (cmd) {
1649 case IPT_SO_GET_INFO:
1650 ret = get_info(sock_net(sk), user, len, 1);
1651 break;
1652 case IPT_SO_GET_ENTRIES:
1653 ret = compat_get_entries(sock_net(sk), user, len);
1654 break;
1655 default:
1656 ret = do_ipt_get_ctl(sk, cmd, user, len);
1657 }
1658 return ret;
1659}
1660#endif
1661
1662static int
1663do_ipt_set_ctl(struct sock *sk, int cmd, void __user *user, unsigned int len)
1664{
1665 int ret;
1666
1667 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
1668 return -EPERM;
1669
1670 switch (cmd) {
1671 case IPT_SO_SET_REPLACE:
1672 ret = do_replace(sock_net(sk), user, len);
1673 break;
1674
1675 case IPT_SO_SET_ADD_COUNTERS:
1676 ret = do_add_counters(sock_net(sk), user, len, 0);
1677 break;
1678
1679 default:
1680 ret = -EINVAL;
1681 }
1682
1683 return ret;
1684}
1685
1686static int
1687do_ipt_get_ctl(struct sock *sk, int cmd, void __user *user, int *len)
1688{
1689 int ret;
1690
1691 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
1692 return -EPERM;
1693
1694 switch (cmd) {
1695 case IPT_SO_GET_INFO:
1696 ret = get_info(sock_net(sk), user, len, 0);
1697 break;
1698
1699 case IPT_SO_GET_ENTRIES:
1700 ret = get_entries(sock_net(sk), user, len);
1701 break;
1702
1703 case IPT_SO_GET_REVISION_MATCH:
1704 case IPT_SO_GET_REVISION_TARGET: {
1705 struct xt_get_revision rev;
1706 int target;
1707
1708 if (*len != sizeof(rev)) {
1709 ret = -EINVAL;
1710 break;
1711 }
1712 if (copy_from_user(&rev, user, sizeof(rev)) != 0) {
1713 ret = -EFAULT;
1714 break;
1715 }
1716 rev.name[sizeof(rev.name)-1] = 0;
1717
1718 if (cmd == IPT_SO_GET_REVISION_TARGET)
1719 target = 1;
1720 else
1721 target = 0;
1722
1723 try_then_request_module(xt_find_revision(AF_INET, rev.name,
1724 rev.revision,
1725 target, &ret),
1726 "ipt_%s", rev.name);
1727 break;
1728 }
1729
1730 default:
1731 ret = -EINVAL;
1732 }
1733
1734 return ret;
1735}
1736
1737static void __ipt_unregister_table(struct net *net, struct xt_table *table)
1738{
1739 struct xt_table_info *private;
1740 void *loc_cpu_entry;
1741 struct module *table_owner = table->me;
1742 struct ipt_entry *iter;
1743
1744 private = xt_unregister_table(table);
1745
1746
1747 loc_cpu_entry = private->entries;
1748 xt_entry_foreach(iter, loc_cpu_entry, private->size)
1749 cleanup_entry(iter, net);
1750 if (private->number > private->initial_entries)
1751 module_put(table_owner);
1752 xt_free_table_info(private);
1753}
1754
1755int ipt_register_table(struct net *net, const struct xt_table *table,
1756 const struct ipt_replace *repl,
1757 const struct nf_hook_ops *ops, struct xt_table **res)
1758{
1759 int ret;
1760 struct xt_table_info *newinfo;
1761 struct xt_table_info bootstrap = {0};
1762 void *loc_cpu_entry;
1763 struct xt_table *new_table;
1764
1765 newinfo = xt_alloc_table_info(repl->size);
1766 if (!newinfo)
1767 return -ENOMEM;
1768
1769 loc_cpu_entry = newinfo->entries;
1770 memcpy(loc_cpu_entry, repl->entries, repl->size);
1771
1772 ret = translate_table(net, newinfo, loc_cpu_entry, repl);
1773 if (ret != 0)
1774 goto out_free;
1775
1776 new_table = xt_register_table(net, table, &bootstrap, newinfo);
1777 if (IS_ERR(new_table)) {
1778 ret = PTR_ERR(new_table);
1779 goto out_free;
1780 }
1781
1782
1783 WRITE_ONCE(*res, new_table);
1784 if (!ops)
1785 return 0;
1786
1787 ret = nf_register_net_hooks(net, ops, hweight32(table->valid_hooks));
1788 if (ret != 0) {
1789 __ipt_unregister_table(net, new_table);
1790 *res = NULL;
1791 }
1792
1793 return ret;
1794
1795out_free:
1796 xt_free_table_info(newinfo);
1797 return ret;
1798}
1799
1800void ipt_unregister_table(struct net *net, struct xt_table *table,
1801 const struct nf_hook_ops *ops)
1802{
1803 if (ops)
1804 nf_unregister_net_hooks(net, ops, hweight32(table->valid_hooks));
1805 __ipt_unregister_table(net, table);
1806}
1807
1808
1809static inline bool
1810icmp_type_code_match(u_int8_t test_type, u_int8_t min_code, u_int8_t max_code,
1811 u_int8_t type, u_int8_t code,
1812 bool invert)
1813{
1814 return ((test_type == 0xFF) ||
1815 (type == test_type && code >= min_code && code <= max_code))
1816 ^ invert;
1817}
1818
1819static bool
1820icmp_match(const struct sk_buff *skb, struct xt_action_param *par)
1821{
1822 const struct icmphdr *ic;
1823 struct icmphdr _icmph;
1824 const struct ipt_icmp *icmpinfo = par->matchinfo;
1825
1826
1827 if (par->fragoff != 0)
1828 return false;
1829
1830 ic = skb_header_pointer(skb, par->thoff, sizeof(_icmph), &_icmph);
1831 if (ic == NULL) {
1832
1833
1834
1835 par->hotdrop = true;
1836 return false;
1837 }
1838
1839 return icmp_type_code_match(icmpinfo->type,
1840 icmpinfo->code[0],
1841 icmpinfo->code[1],
1842 ic->type, ic->code,
1843 !!(icmpinfo->invflags&IPT_ICMP_INV));
1844}
1845
1846static int icmp_checkentry(const struct xt_mtchk_param *par)
1847{
1848 const struct ipt_icmp *icmpinfo = par->matchinfo;
1849
1850
1851 return (icmpinfo->invflags & ~IPT_ICMP_INV) ? -EINVAL : 0;
1852}
1853
1854static struct xt_target ipt_builtin_tg[] __read_mostly = {
1855 {
1856 .name = XT_STANDARD_TARGET,
1857 .targetsize = sizeof(int),
1858 .family = NFPROTO_IPV4,
1859#ifdef CONFIG_COMPAT
1860 .compatsize = sizeof(compat_int_t),
1861 .compat_from_user = compat_standard_from_user,
1862 .compat_to_user = compat_standard_to_user,
1863#endif
1864 },
1865 {
1866 .name = XT_ERROR_TARGET,
1867 .target = ipt_error,
1868 .targetsize = XT_FUNCTION_MAXNAMELEN,
1869 .family = NFPROTO_IPV4,
1870 },
1871};
1872
1873static struct nf_sockopt_ops ipt_sockopts = {
1874 .pf = PF_INET,
1875 .set_optmin = IPT_BASE_CTL,
1876 .set_optmax = IPT_SO_SET_MAX+1,
1877 .set = do_ipt_set_ctl,
1878#ifdef CONFIG_COMPAT
1879 .compat_set = compat_do_ipt_set_ctl,
1880#endif
1881 .get_optmin = IPT_BASE_CTL,
1882 .get_optmax = IPT_SO_GET_MAX+1,
1883 .get = do_ipt_get_ctl,
1884#ifdef CONFIG_COMPAT
1885 .compat_get = compat_do_ipt_get_ctl,
1886#endif
1887 .owner = THIS_MODULE,
1888};
1889
1890static struct xt_match ipt_builtin_mt[] __read_mostly = {
1891 {
1892 .name = "icmp",
1893 .match = icmp_match,
1894 .matchsize = sizeof(struct ipt_icmp),
1895 .checkentry = icmp_checkentry,
1896 .proto = IPPROTO_ICMP,
1897 .family = NFPROTO_IPV4,
1898 .me = THIS_MODULE,
1899 },
1900};
1901
1902static int __net_init ip_tables_net_init(struct net *net)
1903{
1904 return xt_proto_init(net, NFPROTO_IPV4);
1905}
1906
1907static void __net_exit ip_tables_net_exit(struct net *net)
1908{
1909 xt_proto_fini(net, NFPROTO_IPV4);
1910}
1911
1912static struct pernet_operations ip_tables_net_ops = {
1913 .init = ip_tables_net_init,
1914 .exit = ip_tables_net_exit,
1915};
1916
1917static int __init ip_tables_init(void)
1918{
1919 int ret;
1920
1921 ret = register_pernet_subsys(&ip_tables_net_ops);
1922 if (ret < 0)
1923 goto err1;
1924
1925
1926 ret = xt_register_targets(ipt_builtin_tg, ARRAY_SIZE(ipt_builtin_tg));
1927 if (ret < 0)
1928 goto err2;
1929 ret = xt_register_matches(ipt_builtin_mt, ARRAY_SIZE(ipt_builtin_mt));
1930 if (ret < 0)
1931 goto err4;
1932
1933
1934 ret = nf_register_sockopt(&ipt_sockopts);
1935 if (ret < 0)
1936 goto err5;
1937
1938 return 0;
1939
1940err5:
1941 xt_unregister_matches(ipt_builtin_mt, ARRAY_SIZE(ipt_builtin_mt));
1942err4:
1943 xt_unregister_targets(ipt_builtin_tg, ARRAY_SIZE(ipt_builtin_tg));
1944err2:
1945 unregister_pernet_subsys(&ip_tables_net_ops);
1946err1:
1947 return ret;
1948}
1949
1950static void __exit ip_tables_fini(void)
1951{
1952 nf_unregister_sockopt(&ipt_sockopts);
1953
1954 xt_unregister_matches(ipt_builtin_mt, ARRAY_SIZE(ipt_builtin_mt));
1955 xt_unregister_targets(ipt_builtin_tg, ARRAY_SIZE(ipt_builtin_tg));
1956 unregister_pernet_subsys(&ip_tables_net_ops);
1957}
1958
1959EXPORT_SYMBOL(ipt_register_table);
1960EXPORT_SYMBOL(ipt_unregister_table);
1961EXPORT_SYMBOL(ipt_do_table);
1962module_init(ip_tables_init);
1963module_exit(ip_tables_fini);
1964
