1
2
3
4
5
6
7
8
9
10
11
12#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
13#include <linux/kernel.h>
14#include <linux/skbuff.h>
15#include <linux/netdevice.h>
16#include <linux/capability.h>
17#include <linux/if_arp.h>
18#include <linux/kmod.h>
19#include <linux/vmalloc.h>
20#include <linux/proc_fs.h>
21#include <linux/module.h>
22#include <linux/init.h>
23#include <linux/mutex.h>
24#include <linux/err.h>
25#include <net/compat.h>
26#include <net/sock.h>
27#include <asm/uaccess.h>
28
29#include <linux/netfilter/x_tables.h>
30#include <linux/netfilter_arp/arp_tables.h>
31#include "../../netfilter/xt_repldata.h"
32
33MODULE_LICENSE("GPL");
34MODULE_AUTHOR("David S. Miller <davem@redhat.com>");
35MODULE_DESCRIPTION("arptables core");
36
37
38
39
40#ifdef DEBUG_ARP_TABLES
41#define dprintf(format, args...) printk(format , ## args)
42#else
43#define dprintf(format, args...)
44#endif
45
46#ifdef DEBUG_ARP_TABLES_USER
47#define duprintf(format, args...) printk(format , ## args)
48#else
49#define duprintf(format, args...)
50#endif
51
52#ifdef CONFIG_NETFILTER_DEBUG
53#define ARP_NF_ASSERT(x) WARN_ON(!(x))
54#else
55#define ARP_NF_ASSERT(x)
56#endif
57
58void *arpt_alloc_initial_table(const struct xt_table *info)
59{
60 return xt_alloc_initial_table(arpt, ARPT);
61}
62EXPORT_SYMBOL_GPL(arpt_alloc_initial_table);
63
64static inline int arp_devaddr_compare(const struct arpt_devaddr_info *ap,
65 const char *hdr_addr, int len)
66{
67 int i, ret;
68
69 if (len > ARPT_DEV_ADDR_LEN_MAX)
70 len = ARPT_DEV_ADDR_LEN_MAX;
71
72 ret = 0;
73 for (i = 0; i < len; i++)
74 ret |= (hdr_addr[i] ^ ap->addr[i]) & ap->mask[i];
75
76 return ret != 0;
77}
78
79
80
81
82
83
84static unsigned long ifname_compare(const char *_a, const char *_b, const char *_mask)
85{
86#ifdef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
87 unsigned long ret = ifname_compare_aligned(_a, _b, _mask);
88#else
89 unsigned long ret = 0;
90 const u16 *a = (const u16 *)_a;
91 const u16 *b = (const u16 *)_b;
92 const u16 *mask = (const u16 *)_mask;
93 int i;
94
95 for (i = 0; i < IFNAMSIZ/sizeof(u16); i++)
96 ret |= (a[i] ^ b[i]) & mask[i];
97#endif
98 return ret;
99}
100
101
102static inline int arp_packet_match(const struct arphdr *arphdr,
103 struct net_device *dev,
104 const char *indev,
105 const char *outdev,
106 const struct arpt_arp *arpinfo)
107{
108 const char *arpptr = (char *)(arphdr + 1);
109 const char *src_devaddr, *tgt_devaddr;
110 __be32 src_ipaddr, tgt_ipaddr;
111 long ret;
112
113#define FWINV(bool, invflg) ((bool) ^ !!(arpinfo->invflags & (invflg)))
114
115 if (FWINV((arphdr->ar_op & arpinfo->arpop_mask) != arpinfo->arpop,
116 ARPT_INV_ARPOP)) {
117 dprintf("ARP operation field mismatch.\n");
118 dprintf("ar_op: %04x info->arpop: %04x info->arpop_mask: %04x\n",
119 arphdr->ar_op, arpinfo->arpop, arpinfo->arpop_mask);
120 return 0;
121 }
122
123 if (FWINV((arphdr->ar_hrd & arpinfo->arhrd_mask) != arpinfo->arhrd,
124 ARPT_INV_ARPHRD)) {
125 dprintf("ARP hardware address format mismatch.\n");
126 dprintf("ar_hrd: %04x info->arhrd: %04x info->arhrd_mask: %04x\n",
127 arphdr->ar_hrd, arpinfo->arhrd, arpinfo->arhrd_mask);
128 return 0;
129 }
130
131 if (FWINV((arphdr->ar_pro & arpinfo->arpro_mask) != arpinfo->arpro,
132 ARPT_INV_ARPPRO)) {
133 dprintf("ARP protocol address format mismatch.\n");
134 dprintf("ar_pro: %04x info->arpro: %04x info->arpro_mask: %04x\n",
135 arphdr->ar_pro, arpinfo->arpro, arpinfo->arpro_mask);
136 return 0;
137 }
138
139 if (FWINV((arphdr->ar_hln & arpinfo->arhln_mask) != arpinfo->arhln,
140 ARPT_INV_ARPHLN)) {
141 dprintf("ARP hardware address length mismatch.\n");
142 dprintf("ar_hln: %02x info->arhln: %02x info->arhln_mask: %02x\n",
143 arphdr->ar_hln, arpinfo->arhln, arpinfo->arhln_mask);
144 return 0;
145 }
146
147 src_devaddr = arpptr;
148 arpptr += dev->addr_len;
149 memcpy(&src_ipaddr, arpptr, sizeof(u32));
150 arpptr += sizeof(u32);
151 tgt_devaddr = arpptr;
152 arpptr += dev->addr_len;
153 memcpy(&tgt_ipaddr, arpptr, sizeof(u32));
154
155 if (FWINV(arp_devaddr_compare(&arpinfo->src_devaddr, src_devaddr, dev->addr_len),
156 ARPT_INV_SRCDEVADDR) ||
157 FWINV(arp_devaddr_compare(&arpinfo->tgt_devaddr, tgt_devaddr, dev->addr_len),
158 ARPT_INV_TGTDEVADDR)) {
159 dprintf("Source or target device address mismatch.\n");
160
161 return 0;
162 }
163
164 if (FWINV((src_ipaddr & arpinfo->smsk.s_addr) != arpinfo->src.s_addr,
165 ARPT_INV_SRCIP) ||
166 FWINV(((tgt_ipaddr & arpinfo->tmsk.s_addr) != arpinfo->tgt.s_addr),
167 ARPT_INV_TGTIP)) {
168 dprintf("Source or target IP address mismatch.\n");
169
170 dprintf("SRC: %pI4. Mask: %pI4. Target: %pI4.%s\n",
171 &src_ipaddr,
172 &arpinfo->smsk.s_addr,
173 &arpinfo->src.s_addr,
174 arpinfo->invflags & ARPT_INV_SRCIP ? " (INV)" : "");
175 dprintf("TGT: %pI4 Mask: %pI4 Target: %pI4.%s\n",
176 &tgt_ipaddr,
177 &arpinfo->tmsk.s_addr,
178 &arpinfo->tgt.s_addr,
179 arpinfo->invflags & ARPT_INV_TGTIP ? " (INV)" : "");
180 return 0;
181 }
182
183
184 ret = ifname_compare(indev, arpinfo->iniface, arpinfo->iniface_mask);
185
186 if (FWINV(ret != 0, ARPT_INV_VIA_IN)) {
187 dprintf("VIA in mismatch (%s vs %s).%s\n",
188 indev, arpinfo->iniface,
189 arpinfo->invflags&ARPT_INV_VIA_IN ?" (INV)":"");
190 return 0;
191 }
192
193 ret = ifname_compare(outdev, arpinfo->outiface, arpinfo->outiface_mask);
194
195 if (FWINV(ret != 0, ARPT_INV_VIA_OUT)) {
196 dprintf("VIA out mismatch (%s vs %s).%s\n",
197 outdev, arpinfo->outiface,
198 arpinfo->invflags&ARPT_INV_VIA_OUT ?" (INV)":"");
199 return 0;
200 }
201
202 return 1;
203#undef FWINV
204}
205
206static inline int arp_checkentry(const struct arpt_arp *arp)
207{
208 if (arp->flags & ~ARPT_F_MASK) {
209 duprintf("Unknown flag bits set: %08X\n",
210 arp->flags & ~ARPT_F_MASK);
211 return 0;
212 }
213 if (arp->invflags & ~ARPT_INV_MASK) {
214 duprintf("Unknown invflag bits set: %08X\n",
215 arp->invflags & ~ARPT_INV_MASK);
216 return 0;
217 }
218
219 return 1;
220}
221
222static unsigned int
223arpt_error(struct sk_buff *skb, const struct xt_action_param *par)
224{
225 net_err_ratelimited("arp_tables: error: '%s'\n",
226 (const char *)par->targinfo);
227
228 return NF_DROP;
229}
230
231static inline const struct xt_entry_target *
232arpt_get_target_c(const struct arpt_entry *e)
233{
234 return arpt_get_target((struct arpt_entry *)e);
235}
236
237static inline struct arpt_entry *
238get_entry(const void *base, unsigned int offset)
239{
240 return (struct arpt_entry *)(base + offset);
241}
242
243static inline __pure
244struct arpt_entry *arpt_next_entry(const struct arpt_entry *entry)
245{
246 return (void *)entry + entry->next_offset;
247}
248
249unsigned int arpt_do_table(struct sk_buff *skb,
250 unsigned int hook,
251 const struct nf_hook_state *state,
252 struct xt_table *table)
253{
254 static const char nulldevname[IFNAMSIZ] __attribute__((aligned(sizeof(long))));
255 unsigned int verdict = NF_DROP;
256 const struct arphdr *arp;
257 struct arpt_entry *e, *back;
258 const char *indev, *outdev;
259 void *table_base;
260 const struct xt_table_info *private;
261 struct xt_action_param acpar;
262 unsigned int addend;
263
264 if (!pskb_may_pull(skb, arp_hdr_len(skb->dev)))
265 return NF_DROP;
266
267 indev = state->in ? state->in->name : nulldevname;
268 outdev = state->out ? state->out->name : nulldevname;
269
270 local_bh_disable();
271 addend = xt_write_recseq_begin();
272 private = table->private;
273
274
275
276
277 smp_read_barrier_depends();
278 table_base = private->entries[smp_processor_id()];
279
280 e = get_entry(table_base, private->hook_entry[hook]);
281 back = get_entry(table_base, private->underflow[hook]);
282
283 acpar.in = state->in;
284 acpar.out = state->out;
285 acpar.hooknum = hook;
286 acpar.family = NFPROTO_ARP;
287 acpar.hotdrop = false;
288
289 arp = arp_hdr(skb);
290 do {
291 const struct xt_entry_target *t;
292
293 if (!arp_packet_match(arp, skb->dev, indev, outdev, &e->arp)) {
294 e = arpt_next_entry(e);
295 continue;
296 }
297
298 ADD_COUNTER(e->counters, arp_hdr_len(skb->dev), 1);
299
300 t = arpt_get_target_c(e);
301
302
303 if (!t->u.kernel.target->target) {
304 int v;
305
306 v = ((struct xt_standard_target *)t)->verdict;
307 if (v < 0) {
308
309 if (v != XT_RETURN) {
310 verdict = (unsigned int)(-v) - 1;
311 break;
312 }
313 e = back;
314 back = get_entry(table_base, back->comefrom);
315 continue;
316 }
317 if (table_base + v
318 != arpt_next_entry(e)) {
319
320 struct arpt_entry *next = arpt_next_entry(e);
321 next->comefrom = (void *)back - table_base;
322
323
324 back = next;
325 }
326
327 e = get_entry(table_base, v);
328 continue;
329 }
330
331
332
333
334 acpar.target = t->u.kernel.target;
335 acpar.targinfo = t->data;
336 verdict = t->u.kernel.target->target(skb, &acpar);
337
338
339 arp = arp_hdr(skb);
340
341 if (verdict == XT_CONTINUE)
342 e = arpt_next_entry(e);
343 else
344
345 break;
346 } while (!acpar.hotdrop);
347 xt_write_recseq_end(addend);
348 local_bh_enable();
349
350 if (acpar.hotdrop)
351 return NF_DROP;
352 else
353 return verdict;
354}
355
356
357static inline bool unconditional(const struct arpt_arp *arp)
358{
359 static const struct arpt_arp uncond;
360
361 return memcmp(arp, &uncond, sizeof(uncond)) == 0;
362}
363
364
365
366
367static int mark_source_chains(const struct xt_table_info *newinfo,
368 unsigned int valid_hooks, void *entry0)
369{
370 unsigned int hook;
371
372
373
374
375 for (hook = 0; hook < NF_ARP_NUMHOOKS; hook++) {
376 unsigned int pos = newinfo->hook_entry[hook];
377 struct arpt_entry *e
378 = (struct arpt_entry *)(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 *)arpt_get_target_c(e);
389 int visited = e->comefrom & (1 << hook);
390
391 if (e->comefrom & (1 << NF_ARP_NUMHOOKS)) {
392 pr_notice("arptables: loop hook %u pos %u %08X.\n",
393 hook, pos, e->comefrom);
394 return 0;
395 }
396 e->comefrom
397 |= ((1 << hook) | (1 << NF_ARP_NUMHOOKS));
398
399
400 if ((e->target_offset == sizeof(struct arpt_entry) &&
401 (strcmp(t->target.u.user.name,
402 XT_STANDARD_TARGET) == 0) &&
403 t->verdict < 0 && unconditional(&e->arp)) ||
404 visited) {
405 unsigned int oldpos, size;
406
407 if ((strcmp(t->target.u.user.name,
408 XT_STANDARD_TARGET) == 0) &&
409 t->verdict < -NF_MAX_VERDICT - 1) {
410 duprintf("mark_source_chains: bad "
411 "negative verdict (%i)\n",
412 t->verdict);
413 return 0;
414 }
415
416
417
418
419 do {
420 e->comefrom ^= (1<<NF_ARP_NUMHOOKS);
421 oldpos = pos;
422 pos = e->counters.pcnt;
423 e->counters.pcnt = 0;
424
425
426 if (pos == oldpos)
427 goto next;
428
429 e = (struct arpt_entry *)
430 (entry0 + pos);
431 } while (oldpos == pos + e->next_offset);
432
433
434 size = e->next_offset;
435 e = (struct arpt_entry *)
436 (entry0 + pos + size);
437 e->counters.pcnt = pos;
438 pos += size;
439 } else {
440 int newpos = t->verdict;
441
442 if (strcmp(t->target.u.user.name,
443 XT_STANDARD_TARGET) == 0 &&
444 newpos >= 0) {
445 if (newpos > newinfo->size -
446 sizeof(struct arpt_entry)) {
447 duprintf("mark_source_chains: "
448 "bad verdict (%i)\n",
449 newpos);
450 return 0;
451 }
452
453
454 duprintf("Jump rule %u -> %u\n",
455 pos, newpos);
456 } else {
457
458 newpos = pos + e->next_offset;
459 }
460 e = (struct arpt_entry *)
461 (entry0 + newpos);
462 e->counters.pcnt = pos;
463 pos = newpos;
464 }
465 }
466 next:
467 duprintf("Finished chain %u\n", hook);
468 }
469 return 1;
470}
471
472static inline int check_entry(const struct arpt_entry *e, const char *name)
473{
474 const struct xt_entry_target *t;
475
476 if (!arp_checkentry(&e->arp)) {
477 duprintf("arp_tables: arp check failed %p %s.\n", e, name);
478 return -EINVAL;
479 }
480
481 if (e->target_offset + sizeof(struct xt_entry_target) > e->next_offset)
482 return -EINVAL;
483
484 t = arpt_get_target_c(e);
485 if (e->target_offset + t->u.target_size > e->next_offset)
486 return -EINVAL;
487
488 return 0;
489}
490
491static inline int check_target(struct arpt_entry *e, const char *name)
492{
493 struct xt_entry_target *t = arpt_get_target(e);
494 int ret;
495 struct xt_tgchk_param par = {
496 .table = name,
497 .entryinfo = e,
498 .target = t->u.kernel.target,
499 .targinfo = t->data,
500 .hook_mask = e->comefrom,
501 .family = NFPROTO_ARP,
502 };
503
504 ret = xt_check_target(&par, t->u.target_size - sizeof(*t), 0, false);
505 if (ret < 0) {
506 duprintf("arp_tables: check failed for `%s'.\n",
507 t->u.kernel.target->name);
508 return ret;
509 }
510 return 0;
511}
512
513static inline int
514find_check_entry(struct arpt_entry *e, const char *name, unsigned int size)
515{
516 struct xt_entry_target *t;
517 struct xt_target *target;
518 int ret;
519
520 ret = check_entry(e, name);
521 if (ret)
522 return ret;
523
524 t = arpt_get_target(e);
525 target = xt_request_find_target(NFPROTO_ARP, t->u.user.name,
526 t->u.user.revision);
527 if (IS_ERR(target)) {
528 duprintf("find_check_entry: `%s' not found\n", t->u.user.name);
529 ret = PTR_ERR(target);
530 goto out;
531 }
532 t->u.kernel.target = target;
533
534 ret = check_target(e, name);
535 if (ret)
536 goto err;
537 return 0;
538err:
539 module_put(t->u.kernel.target->me);
540out:
541 return ret;
542}
543
544static bool check_underflow(const struct arpt_entry *e)
545{
546 const struct xt_entry_target *t;
547 unsigned int verdict;
548
549 if (!unconditional(&e->arp))
550 return false;
551 t = arpt_get_target_c(e);
552 if (strcmp(t->u.user.name, XT_STANDARD_TARGET) != 0)
553 return false;
554 verdict = ((struct xt_standard_target *)t)->verdict;
555 verdict = -verdict - 1;
556 return verdict == NF_DROP || verdict == NF_ACCEPT;
557}
558
559static inline int check_entry_size_and_hooks(struct arpt_entry *e,
560 struct xt_table_info *newinfo,
561 const unsigned char *base,
562 const unsigned char *limit,
563 const unsigned int *hook_entries,
564 const unsigned int *underflows,
565 unsigned int valid_hooks)
566{
567 unsigned int h;
568
569 if ((unsigned long)e % __alignof__(struct arpt_entry) != 0 ||
570 (unsigned char *)e + sizeof(struct arpt_entry) >= limit) {
571 duprintf("Bad offset %p\n", e);
572 return -EINVAL;
573 }
574
575 if (e->next_offset
576 < sizeof(struct arpt_entry) + sizeof(struct xt_entry_target)) {
577 duprintf("checking: element %p size %u\n",
578 e, e->next_offset);
579 return -EINVAL;
580 }
581
582
583 for (h = 0; h < NF_ARP_NUMHOOKS; h++) {
584 if (!(valid_hooks & (1 << h)))
585 continue;
586 if ((unsigned char *)e - base == hook_entries[h])
587 newinfo->hook_entry[h] = hook_entries[h];
588 if ((unsigned char *)e - base == underflows[h]) {
589 if (!check_underflow(e)) {
590 pr_err("Underflows must be unconditional and "
591 "use the STANDARD target with "
592 "ACCEPT/DROP\n");
593 return -EINVAL;
594 }
595 newinfo->underflow[h] = underflows[h];
596 }
597 }
598
599
600 e->counters = ((struct xt_counters) { 0, 0 });
601 e->comefrom = 0;
602 return 0;
603}
604
605static inline void cleanup_entry(struct arpt_entry *e)
606{
607 struct xt_tgdtor_param par;
608 struct xt_entry_target *t;
609
610 t = arpt_get_target(e);
611 par.target = t->u.kernel.target;
612 par.targinfo = t->data;
613 par.family = NFPROTO_ARP;
614 if (par.target->destroy != NULL)
615 par.target->destroy(&par);
616 module_put(par.target->me);
617}
618
619
620
621
622static int translate_table(struct xt_table_info *newinfo, void *entry0,
623 const struct arpt_replace *repl)
624{
625 struct arpt_entry *iter;
626 unsigned int i;
627 int ret = 0;
628
629 newinfo->size = repl->size;
630 newinfo->number = repl->num_entries;
631
632
633 for (i = 0; i < NF_ARP_NUMHOOKS; i++) {
634 newinfo->hook_entry[i] = 0xFFFFFFFF;
635 newinfo->underflow[i] = 0xFFFFFFFF;
636 }
637
638 duprintf("translate_table: size %u\n", newinfo->size);
639 i = 0;
640
641
642 xt_entry_foreach(iter, entry0, newinfo->size) {
643 ret = check_entry_size_and_hooks(iter, newinfo, entry0,
644 entry0 + repl->size,
645 repl->hook_entry,
646 repl->underflow,
647 repl->valid_hooks);
648 if (ret != 0)
649 break;
650 ++i;
651 if (strcmp(arpt_get_target(iter)->u.user.name,
652 XT_ERROR_TARGET) == 0)
653 ++newinfo->stacksize;
654 }
655 duprintf("translate_table: ARPT_ENTRY_ITERATE gives %d\n", ret);
656 if (ret != 0)
657 return ret;
658
659 if (i != repl->num_entries) {
660 duprintf("translate_table: %u not %u entries\n",
661 i, repl->num_entries);
662 return -EINVAL;
663 }
664
665
666 for (i = 0; i < NF_ARP_NUMHOOKS; i++) {
667
668 if (!(repl->valid_hooks & (1 << i)))
669 continue;
670 if (newinfo->hook_entry[i] == 0xFFFFFFFF) {
671 duprintf("Invalid hook entry %u %u\n",
672 i, repl->hook_entry[i]);
673 return -EINVAL;
674 }
675 if (newinfo->underflow[i] == 0xFFFFFFFF) {
676 duprintf("Invalid underflow %u %u\n",
677 i, repl->underflow[i]);
678 return -EINVAL;
679 }
680 }
681
682 if (!mark_source_chains(newinfo, repl->valid_hooks, entry0)) {
683 duprintf("Looping hook\n");
684 return -ELOOP;
685 }
686
687
688 i = 0;
689 xt_entry_foreach(iter, entry0, newinfo->size) {
690 ret = find_check_entry(iter, repl->name, repl->size);
691 if (ret != 0)
692 break;
693 ++i;
694 }
695
696 if (ret != 0) {
697 xt_entry_foreach(iter, entry0, newinfo->size) {
698 if (i-- == 0)
699 break;
700 cleanup_entry(iter);
701 }
702 return ret;
703 }
704
705
706 for_each_possible_cpu(i) {
707 if (newinfo->entries[i] && newinfo->entries[i] != entry0)
708 memcpy(newinfo->entries[i], entry0, newinfo->size);
709 }
710
711 return ret;
712}
713
714static void get_counters(const struct xt_table_info *t,
715 struct xt_counters counters[])
716{
717 struct arpt_entry *iter;
718 unsigned int cpu;
719 unsigned int i;
720
721 for_each_possible_cpu(cpu) {
722 seqcount_t *s = &per_cpu(xt_recseq, cpu);
723
724 i = 0;
725 xt_entry_foreach(iter, t->entries[cpu], t->size) {
726 u64 bcnt, pcnt;
727 unsigned int start;
728
729 do {
730 start = read_seqcount_begin(s);
731 bcnt = iter->counters.bcnt;
732 pcnt = iter->counters.pcnt;
733 } while (read_seqcount_retry(s, start));
734
735 ADD_COUNTER(counters[i], bcnt, pcnt);
736 ++i;
737 }
738 }
739}
740
741static struct xt_counters *alloc_counters(const struct xt_table *table)
742{
743 unsigned int countersize;
744 struct xt_counters *counters;
745 const struct xt_table_info *private = table->private;
746
747
748
749
750
751 countersize = sizeof(struct xt_counters) * private->number;
752 counters = vzalloc(countersize);
753
754 if (counters == NULL)
755 return ERR_PTR(-ENOMEM);
756
757 get_counters(private, counters);
758
759 return counters;
760}
761
762static int copy_entries_to_user(unsigned int total_size,
763 const struct xt_table *table,
764 void __user *userptr)
765{
766 unsigned int off, num;
767 const struct arpt_entry *e;
768 struct xt_counters *counters;
769 struct xt_table_info *private = table->private;
770 int ret = 0;
771 void *loc_cpu_entry;
772
773 counters = alloc_counters(table);
774 if (IS_ERR(counters))
775 return PTR_ERR(counters);
776
777 loc_cpu_entry = private->entries[raw_smp_processor_id()];
778
779 if (copy_to_user(userptr, loc_cpu_entry, total_size) != 0) {
780 ret = -EFAULT;
781 goto free_counters;
782 }
783
784
785
786 for (off = 0, num = 0; off < total_size; off += e->next_offset, num++){
787 const struct xt_entry_target *t;
788
789 e = (struct arpt_entry *)(loc_cpu_entry + off);
790 if (copy_to_user(userptr + off
791 + offsetof(struct arpt_entry, counters),
792 &counters[num],
793 sizeof(counters[num])) != 0) {
794 ret = -EFAULT;
795 goto free_counters;
796 }
797
798 t = arpt_get_target_c(e);
799 if (copy_to_user(userptr + off + e->target_offset
800 + offsetof(struct xt_entry_target,
801 u.user.name),
802 t->u.kernel.target->name,
803 strlen(t->u.kernel.target->name)+1) != 0) {
804 ret = -EFAULT;
805 goto free_counters;
806 }
807 }
808
809 free_counters:
810 vfree(counters);
811 return ret;
812}
813
814#ifdef CONFIG_COMPAT
815static void compat_standard_from_user(void *dst, const void *src)
816{
817 int v = *(compat_int_t *)src;
818
819 if (v > 0)
820 v += xt_compat_calc_jump(NFPROTO_ARP, v);
821 memcpy(dst, &v, sizeof(v));
822}
823
824static int compat_standard_to_user(void __user *dst, const void *src)
825{
826 compat_int_t cv = *(int *)src;
827
828 if (cv > 0)
829 cv -= xt_compat_calc_jump(NFPROTO_ARP, cv);
830 return copy_to_user(dst, &cv, sizeof(cv)) ? -EFAULT : 0;
831}
832
833static int compat_calc_entry(const struct arpt_entry *e,
834 const struct xt_table_info *info,
835 const void *base, struct xt_table_info *newinfo)
836{
837 const struct xt_entry_target *t;
838 unsigned int entry_offset;
839 int off, i, ret;
840
841 off = sizeof(struct arpt_entry) - sizeof(struct compat_arpt_entry);
842 entry_offset = (void *)e - base;
843
844 t = arpt_get_target_c(e);
845 off += xt_compat_target_offset(t->u.kernel.target);
846 newinfo->size -= off;
847 ret = xt_compat_add_offset(NFPROTO_ARP, entry_offset, off);
848 if (ret)
849 return ret;
850
851 for (i = 0; i < NF_ARP_NUMHOOKS; i++) {
852 if (info->hook_entry[i] &&
853 (e < (struct arpt_entry *)(base + info->hook_entry[i])))
854 newinfo->hook_entry[i] -= off;
855 if (info->underflow[i] &&
856 (e < (struct arpt_entry *)(base + info->underflow[i])))
857 newinfo->underflow[i] -= off;
858 }
859 return 0;
860}
861
862static int compat_table_info(const struct xt_table_info *info,
863 struct xt_table_info *newinfo)
864{
865 struct arpt_entry *iter;
866 void *loc_cpu_entry;
867 int ret;
868
869 if (!newinfo || !info)
870 return -EINVAL;
871
872
873 memcpy(newinfo, info, offsetof(struct xt_table_info, entries));
874 newinfo->initial_entries = 0;
875 loc_cpu_entry = info->entries[raw_smp_processor_id()];
876 xt_compat_init_offsets(NFPROTO_ARP, info->number);
877 xt_entry_foreach(iter, loc_cpu_entry, info->size) {
878 ret = compat_calc_entry(iter, info, loc_cpu_entry, newinfo);
879 if (ret != 0)
880 return ret;
881 }
882 return 0;
883}
884#endif
885
886static int get_info(struct net *net, void __user *user,
887 const int *len, int compat)
888{
889 char name[XT_TABLE_MAXNAMELEN];
890 struct xt_table *t;
891 int ret;
892
893 if (*len != sizeof(struct arpt_getinfo)) {
894 duprintf("length %u != %Zu\n", *len,
895 sizeof(struct arpt_getinfo));
896 return -EINVAL;
897 }
898
899 if (copy_from_user(name, user, sizeof(name)) != 0)
900 return -EFAULT;
901
902 name[XT_TABLE_MAXNAMELEN-1] = '\0';
903#ifdef CONFIG_COMPAT
904 if (compat)
905 xt_compat_lock(NFPROTO_ARP);
906#endif
907 t = try_then_request_module(xt_find_table_lock(net, NFPROTO_ARP, name),
908 "arptable_%s", name);
909 if (!IS_ERR_OR_NULL(t)) {
910 struct arpt_getinfo info;
911 const struct xt_table_info *private = t->private;
912#ifdef CONFIG_COMPAT
913 struct xt_table_info tmp;
914
915 if (compat) {
916 ret = compat_table_info(private, &tmp);
917 xt_compat_flush_offsets(NFPROTO_ARP);
918 private = &tmp;
919 }
920#endif
921 memset(&info, 0, sizeof(info));
922 info.valid_hooks = t->valid_hooks;
923 memcpy(info.hook_entry, private->hook_entry,
924 sizeof(info.hook_entry));
925 memcpy(info.underflow, private->underflow,
926 sizeof(info.underflow));
927 info.num_entries = private->number;
928 info.size = private->size;
929 strcpy(info.name, name);
930
931 if (copy_to_user(user, &info, *len) != 0)
932 ret = -EFAULT;
933 else
934 ret = 0;
935 xt_table_unlock(t);
936 module_put(t->me);
937 } else
938 ret = t ? PTR_ERR(t) : -ENOENT;
939#ifdef CONFIG_COMPAT
940 if (compat)
941 xt_compat_unlock(NFPROTO_ARP);
942#endif
943 return ret;
944}
945
946static int get_entries(struct net *net, struct arpt_get_entries __user *uptr,
947 const int *len)
948{
949 int ret;
950 struct arpt_get_entries get;
951 struct xt_table *t;
952
953 if (*len < sizeof(get)) {
954 duprintf("get_entries: %u < %Zu\n", *len, sizeof(get));
955 return -EINVAL;
956 }
957 if (copy_from_user(&get, uptr, sizeof(get)) != 0)
958 return -EFAULT;
959 if (*len != sizeof(struct arpt_get_entries) + get.size) {
960 duprintf("get_entries: %u != %Zu\n", *len,
961 sizeof(struct arpt_get_entries) + get.size);
962 return -EINVAL;
963 }
964
965 t = xt_find_table_lock(net, NFPROTO_ARP, get.name);
966 if (!IS_ERR_OR_NULL(t)) {
967 const struct xt_table_info *private = t->private;
968
969 duprintf("t->private->number = %u\n",
970 private->number);
971 if (get.size == private->size)
972 ret = copy_entries_to_user(private->size,
973 t, uptr->entrytable);
974 else {
975 duprintf("get_entries: I've got %u not %u!\n",
976 private->size, get.size);
977 ret = -EAGAIN;
978 }
979 module_put(t->me);
980 xt_table_unlock(t);
981 } else
982 ret = t ? PTR_ERR(t) : -ENOENT;
983
984 return ret;
985}
986
987static int __do_replace(struct net *net, const char *name,
988 unsigned int valid_hooks,
989 struct xt_table_info *newinfo,
990 unsigned int num_counters,
991 void __user *counters_ptr)
992{
993 int ret;
994 struct xt_table *t;
995 struct xt_table_info *oldinfo;
996 struct xt_counters *counters;
997 void *loc_cpu_old_entry;
998 struct arpt_entry *iter;
999
1000 ret = 0;
1001 counters = vzalloc(num_counters * sizeof(struct xt_counters));
1002 if (!counters) {
1003 ret = -ENOMEM;
1004 goto out;
1005 }
1006
1007 t = try_then_request_module(xt_find_table_lock(net, NFPROTO_ARP, name),
1008 "arptable_%s", name);
1009 if (IS_ERR_OR_NULL(t)) {
1010 ret = t ? PTR_ERR(t) : -ENOENT;
1011 goto free_newinfo_counters_untrans;
1012 }
1013
1014
1015 if (valid_hooks != t->valid_hooks) {
1016 duprintf("Valid hook crap: %08X vs %08X\n",
1017 valid_hooks, t->valid_hooks);
1018 ret = -EINVAL;
1019 goto put_module;
1020 }
1021
1022 oldinfo = xt_replace_table(t, num_counters, newinfo, &ret);
1023 if (!oldinfo)
1024 goto put_module;
1025
1026
1027 duprintf("do_replace: oldnum=%u, initnum=%u, newnum=%u\n",
1028 oldinfo->number, oldinfo->initial_entries, newinfo->number);
1029 if ((oldinfo->number > oldinfo->initial_entries) ||
1030 (newinfo->number <= oldinfo->initial_entries))
1031 module_put(t->me);
1032 if ((oldinfo->number > oldinfo->initial_entries) &&
1033 (newinfo->number <= oldinfo->initial_entries))
1034 module_put(t->me);
1035
1036
1037 get_counters(oldinfo, counters);
1038
1039
1040 loc_cpu_old_entry = oldinfo->entries[raw_smp_processor_id()];
1041 xt_entry_foreach(iter, loc_cpu_old_entry, oldinfo->size)
1042 cleanup_entry(iter);
1043
1044 xt_free_table_info(oldinfo);
1045 if (copy_to_user(counters_ptr, counters,
1046 sizeof(struct xt_counters) * num_counters) != 0) {
1047
1048 net_warn_ratelimited("arptables: counters copy to user failed while replacing table\n");
1049 }
1050 vfree(counters);
1051 xt_table_unlock(t);
1052 return ret;
1053
1054 put_module:
1055 module_put(t->me);
1056 xt_table_unlock(t);
1057 free_newinfo_counters_untrans:
1058 vfree(counters);
1059 out:
1060 return ret;
1061}
1062
1063static int do_replace(struct net *net, const void __user *user,
1064 unsigned int len)
1065{
1066 int ret;
1067 struct arpt_replace tmp;
1068 struct xt_table_info *newinfo;
1069 void *loc_cpu_entry;
1070 struct arpt_entry *iter;
1071
1072 if (copy_from_user(&tmp, user, sizeof(tmp)) != 0)
1073 return -EFAULT;
1074
1075
1076 if (tmp.num_counters >= INT_MAX / sizeof(struct xt_counters))
1077 return -ENOMEM;
1078 if (tmp.num_counters == 0)
1079 return -EINVAL;
1080
1081 tmp.name[sizeof(tmp.name)-1] = 0;
1082
1083 newinfo = xt_alloc_table_info(tmp.size);
1084 if (!newinfo)
1085 return -ENOMEM;
1086
1087
1088 loc_cpu_entry = newinfo->entries[raw_smp_processor_id()];
1089 if (copy_from_user(loc_cpu_entry, user + sizeof(tmp),
1090 tmp.size) != 0) {
1091 ret = -EFAULT;
1092 goto free_newinfo;
1093 }
1094
1095 ret = translate_table(newinfo, loc_cpu_entry, &tmp);
1096 if (ret != 0)
1097 goto free_newinfo;
1098
1099 duprintf("arp_tables: Translated table\n");
1100
1101 ret = __do_replace(net, tmp.name, tmp.valid_hooks, newinfo,
1102 tmp.num_counters, tmp.counters);
1103 if (ret)
1104 goto free_newinfo_untrans;
1105 return 0;
1106
1107 free_newinfo_untrans:
1108 xt_entry_foreach(iter, loc_cpu_entry, newinfo->size)
1109 cleanup_entry(iter);
1110 free_newinfo:
1111 xt_free_table_info(newinfo);
1112 return ret;
1113}
1114
1115static int do_add_counters(struct net *net, const void __user *user,
1116 unsigned int len, int compat)
1117{
1118 unsigned int i, curcpu;
1119 struct xt_counters_info tmp;
1120 struct xt_counters *paddc;
1121 unsigned int num_counters;
1122 const char *name;
1123 int size;
1124 void *ptmp;
1125 struct xt_table *t;
1126 const struct xt_table_info *private;
1127 int ret = 0;
1128 void *loc_cpu_entry;
1129 struct arpt_entry *iter;
1130 unsigned int addend;
1131#ifdef CONFIG_COMPAT
1132 struct compat_xt_counters_info compat_tmp;
1133
1134 if (compat) {
1135 ptmp = &compat_tmp;
1136 size = sizeof(struct compat_xt_counters_info);
1137 } else
1138#endif
1139 {
1140 ptmp = &tmp;
1141 size = sizeof(struct xt_counters_info);
1142 }
1143
1144 if (copy_from_user(ptmp, user, size) != 0)
1145 return -EFAULT;
1146
1147#ifdef CONFIG_COMPAT
1148 if (compat) {
1149 num_counters = compat_tmp.num_counters;
1150 name = compat_tmp.name;
1151 } else
1152#endif
1153 {
1154 num_counters = tmp.num_counters;
1155 name = tmp.name;
1156 }
1157
1158 if (len != size + num_counters * sizeof(struct xt_counters))
1159 return -EINVAL;
1160
1161 paddc = vmalloc(len - size);
1162 if (!paddc)
1163 return -ENOMEM;
1164
1165 if (copy_from_user(paddc, user + size, len - size) != 0) {
1166 ret = -EFAULT;
1167 goto free;
1168 }
1169
1170 t = xt_find_table_lock(net, NFPROTO_ARP, name);
1171 if (IS_ERR_OR_NULL(t)) {
1172 ret = t ? PTR_ERR(t) : -ENOENT;
1173 goto free;
1174 }
1175
1176 local_bh_disable();
1177 private = t->private;
1178 if (private->number != num_counters) {
1179 ret = -EINVAL;
1180 goto unlock_up_free;
1181 }
1182
1183 i = 0;
1184
1185 curcpu = smp_processor_id();
1186 loc_cpu_entry = private->entries[curcpu];
1187 addend = xt_write_recseq_begin();
1188 xt_entry_foreach(iter, loc_cpu_entry, private->size) {
1189 ADD_COUNTER(iter->counters, paddc[i].bcnt, paddc[i].pcnt);
1190 ++i;
1191 }
1192 xt_write_recseq_end(addend);
1193 unlock_up_free:
1194 local_bh_enable();
1195 xt_table_unlock(t);
1196 module_put(t->me);
1197 free:
1198 vfree(paddc);
1199
1200 return ret;
1201}
1202
1203#ifdef CONFIG_COMPAT
1204static inline void compat_release_entry(struct compat_arpt_entry *e)
1205{
1206 struct xt_entry_target *t;
1207
1208 t = compat_arpt_get_target(e);
1209 module_put(t->u.kernel.target->me);
1210}
1211
1212static inline int
1213check_compat_entry_size_and_hooks(struct compat_arpt_entry *e,
1214 struct xt_table_info *newinfo,
1215 unsigned int *size,
1216 const unsigned char *base,
1217 const unsigned char *limit,
1218 const unsigned int *hook_entries,
1219 const unsigned int *underflows,
1220 const char *name)
1221{
1222 struct xt_entry_target *t;
1223 struct xt_target *target;
1224 unsigned int entry_offset;
1225 int ret, off, h;
1226
1227 duprintf("check_compat_entry_size_and_hooks %p\n", e);
1228 if ((unsigned long)e % __alignof__(struct compat_arpt_entry) != 0 ||
1229 (unsigned char *)e + sizeof(struct compat_arpt_entry) >= limit) {
1230 duprintf("Bad offset %p, limit = %p\n", e, limit);
1231 return -EINVAL;
1232 }
1233
1234 if (e->next_offset < sizeof(struct compat_arpt_entry) +
1235 sizeof(struct compat_xt_entry_target)) {
1236 duprintf("checking: element %p size %u\n",
1237 e, e->next_offset);
1238 return -EINVAL;
1239 }
1240
1241
1242 ret = check_entry((struct arpt_entry *)e, name);
1243 if (ret)
1244 return ret;
1245
1246 off = sizeof(struct arpt_entry) - sizeof(struct compat_arpt_entry);
1247 entry_offset = (void *)e - (void *)base;
1248
1249 t = compat_arpt_get_target(e);
1250 target = xt_request_find_target(NFPROTO_ARP, t->u.user.name,
1251 t->u.user.revision);
1252 if (IS_ERR(target)) {
1253 duprintf("check_compat_entry_size_and_hooks: `%s' not found\n",
1254 t->u.user.name);
1255 ret = PTR_ERR(target);
1256 goto out;
1257 }
1258 t->u.kernel.target = target;
1259
1260 off += xt_compat_target_offset(target);
1261 *size += off;
1262 ret = xt_compat_add_offset(NFPROTO_ARP, entry_offset, off);
1263 if (ret)
1264 goto release_target;
1265
1266
1267 for (h = 0; h < NF_ARP_NUMHOOKS; h++) {
1268 if ((unsigned char *)e - base == hook_entries[h])
1269 newinfo->hook_entry[h] = hook_entries[h];
1270 if ((unsigned char *)e - base == underflows[h])
1271 newinfo->underflow[h] = underflows[h];
1272 }
1273
1274
1275 memset(&e->counters, 0, sizeof(e->counters));
1276 e->comefrom = 0;
1277 return 0;
1278
1279release_target:
1280 module_put(t->u.kernel.target->me);
1281out:
1282 return ret;
1283}
1284
1285static int
1286compat_copy_entry_from_user(struct compat_arpt_entry *e, void **dstptr,
1287 unsigned int *size, const char *name,
1288 struct xt_table_info *newinfo, unsigned char *base)
1289{
1290 struct xt_entry_target *t;
1291 struct xt_target *target;
1292 struct arpt_entry *de;
1293 unsigned int origsize;
1294 int ret, h;
1295
1296 ret = 0;
1297 origsize = *size;
1298 de = (struct arpt_entry *)*dstptr;
1299 memcpy(de, e, sizeof(struct arpt_entry));
1300 memcpy(&de->counters, &e->counters, sizeof(e->counters));
1301
1302 *dstptr += sizeof(struct arpt_entry);
1303 *size += sizeof(struct arpt_entry) - sizeof(struct compat_arpt_entry);
1304
1305 de->target_offset = e->target_offset - (origsize - *size);
1306 t = compat_arpt_get_target(e);
1307 target = t->u.kernel.target;
1308 xt_compat_target_from_user(t, dstptr, size);
1309
1310 de->next_offset = e->next_offset - (origsize - *size);
1311 for (h = 0; h < NF_ARP_NUMHOOKS; h++) {
1312 if ((unsigned char *)de - base < newinfo->hook_entry[h])
1313 newinfo->hook_entry[h] -= origsize - *size;
1314 if ((unsigned char *)de - base < newinfo->underflow[h])
1315 newinfo->underflow[h] -= origsize - *size;
1316 }
1317 return ret;
1318}
1319
1320static int translate_compat_table(const char *name,
1321 unsigned int valid_hooks,
1322 struct xt_table_info **pinfo,
1323 void **pentry0,
1324 unsigned int total_size,
1325 unsigned int number,
1326 unsigned int *hook_entries,
1327 unsigned int *underflows)
1328{
1329 unsigned int i, j;
1330 struct xt_table_info *newinfo, *info;
1331 void *pos, *entry0, *entry1;
1332 struct compat_arpt_entry *iter0;
1333 struct arpt_entry *iter1;
1334 unsigned int size;
1335 int ret = 0;
1336
1337 info = *pinfo;
1338 entry0 = *pentry0;
1339 size = total_size;
1340 info->number = number;
1341
1342
1343 for (i = 0; i < NF_ARP_NUMHOOKS; i++) {
1344 info->hook_entry[i] = 0xFFFFFFFF;
1345 info->underflow[i] = 0xFFFFFFFF;
1346 }
1347
1348 duprintf("translate_compat_table: size %u\n", info->size);
1349 j = 0;
1350 xt_compat_lock(NFPROTO_ARP);
1351 xt_compat_init_offsets(NFPROTO_ARP, number);
1352
1353 xt_entry_foreach(iter0, entry0, total_size) {
1354 ret = check_compat_entry_size_and_hooks(iter0, info, &size,
1355 entry0,
1356 entry0 + total_size,
1357 hook_entries,
1358 underflows,
1359 name);
1360 if (ret != 0)
1361 goto out_unlock;
1362 ++j;
1363 }
1364
1365 ret = -EINVAL;
1366 if (j != number) {
1367 duprintf("translate_compat_table: %u not %u entries\n",
1368 j, number);
1369 goto out_unlock;
1370 }
1371
1372
1373 for (i = 0; i < NF_ARP_NUMHOOKS; i++) {
1374
1375 if (!(valid_hooks & (1 << i)))
1376 continue;
1377 if (info->hook_entry[i] == 0xFFFFFFFF) {
1378 duprintf("Invalid hook entry %u %u\n",
1379 i, hook_entries[i]);
1380 goto out_unlock;
1381 }
1382 if (info->underflow[i] == 0xFFFFFFFF) {
1383 duprintf("Invalid underflow %u %u\n",
1384 i, underflows[i]);
1385 goto out_unlock;
1386 }
1387 }
1388
1389 ret = -ENOMEM;
1390 newinfo = xt_alloc_table_info(size);
1391 if (!newinfo)
1392 goto out_unlock;
1393
1394 newinfo->number = number;
1395 for (i = 0; i < NF_ARP_NUMHOOKS; i++) {
1396 newinfo->hook_entry[i] = info->hook_entry[i];
1397 newinfo->underflow[i] = info->underflow[i];
1398 }
1399 entry1 = newinfo->entries[raw_smp_processor_id()];
1400 pos = entry1;
1401 size = total_size;
1402 xt_entry_foreach(iter0, entry0, total_size) {
1403 ret = compat_copy_entry_from_user(iter0, &pos, &size,
1404 name, newinfo, entry1);
1405 if (ret != 0)
1406 break;
1407 }
1408 xt_compat_flush_offsets(NFPROTO_ARP);
1409 xt_compat_unlock(NFPROTO_ARP);
1410 if (ret)
1411 goto free_newinfo;
1412
1413 ret = -ELOOP;
1414 if (!mark_source_chains(newinfo, valid_hooks, entry1))
1415 goto free_newinfo;
1416
1417 i = 0;
1418 xt_entry_foreach(iter1, entry1, newinfo->size) {
1419 ret = check_target(iter1, name);
1420 if (ret != 0)
1421 break;
1422 ++i;
1423 if (strcmp(arpt_get_target(iter1)->u.user.name,
1424 XT_ERROR_TARGET) == 0)
1425 ++newinfo->stacksize;
1426 }
1427 if (ret) {
1428
1429
1430
1431
1432
1433 int skip = i;
1434 j -= i;
1435 xt_entry_foreach(iter0, entry0, newinfo->size) {
1436 if (skip-- > 0)
1437 continue;
1438 if (j-- == 0)
1439 break;
1440 compat_release_entry(iter0);
1441 }
1442 xt_entry_foreach(iter1, entry1, newinfo->size) {
1443 if (i-- == 0)
1444 break;
1445 cleanup_entry(iter1);
1446 }
1447 xt_free_table_info(newinfo);
1448 return ret;
1449 }
1450
1451
1452 for_each_possible_cpu(i)
1453 if (newinfo->entries[i] && newinfo->entries[i] != entry1)
1454 memcpy(newinfo->entries[i], entry1, newinfo->size);
1455
1456 *pinfo = newinfo;
1457 *pentry0 = entry1;
1458 xt_free_table_info(info);
1459 return 0;
1460
1461free_newinfo:
1462 xt_free_table_info(newinfo);
1463out:
1464 xt_entry_foreach(iter0, entry0, total_size) {
1465 if (j-- == 0)
1466 break;
1467 compat_release_entry(iter0);
1468 }
1469 return ret;
1470out_unlock:
1471 xt_compat_flush_offsets(NFPROTO_ARP);
1472 xt_compat_unlock(NFPROTO_ARP);
1473 goto out;
1474}
1475
1476struct compat_arpt_replace {
1477 char name[XT_TABLE_MAXNAMELEN];
1478 u32 valid_hooks;
1479 u32 num_entries;
1480 u32 size;
1481 u32 hook_entry[NF_ARP_NUMHOOKS];
1482 u32 underflow[NF_ARP_NUMHOOKS];
1483 u32 num_counters;
1484 compat_uptr_t counters;
1485 struct compat_arpt_entry entries[0];
1486};
1487
1488static int compat_do_replace(struct net *net, void __user *user,
1489 unsigned int len)
1490{
1491 int ret;
1492 struct compat_arpt_replace tmp;
1493 struct xt_table_info *newinfo;
1494 void *loc_cpu_entry;
1495 struct arpt_entry *iter;
1496
1497 if (copy_from_user(&tmp, user, sizeof(tmp)) != 0)
1498 return -EFAULT;
1499
1500
1501 if (tmp.size >= INT_MAX / num_possible_cpus())
1502 return -ENOMEM;
1503 if (tmp.num_counters >= INT_MAX / sizeof(struct xt_counters))
1504 return -ENOMEM;
1505 if (tmp.num_counters == 0)
1506 return -EINVAL;
1507
1508 tmp.name[sizeof(tmp.name)-1] = 0;
1509
1510 newinfo = xt_alloc_table_info(tmp.size);
1511 if (!newinfo)
1512 return -ENOMEM;
1513
1514
1515 loc_cpu_entry = newinfo->entries[raw_smp_processor_id()];
1516 if (copy_from_user(loc_cpu_entry, user + sizeof(tmp), tmp.size) != 0) {
1517 ret = -EFAULT;
1518 goto free_newinfo;
1519 }
1520
1521 ret = translate_compat_table(tmp.name, tmp.valid_hooks,
1522 &newinfo, &loc_cpu_entry, tmp.size,
1523 tmp.num_entries, tmp.hook_entry,
1524 tmp.underflow);
1525 if (ret != 0)
1526 goto free_newinfo;
1527
1528 duprintf("compat_do_replace: Translated table\n");
1529
1530 ret = __do_replace(net, tmp.name, tmp.valid_hooks, newinfo,
1531 tmp.num_counters, compat_ptr(tmp.counters));
1532 if (ret)
1533 goto free_newinfo_untrans;
1534 return 0;
1535
1536 free_newinfo_untrans:
1537 xt_entry_foreach(iter, loc_cpu_entry, newinfo->size)
1538 cleanup_entry(iter);
1539 free_newinfo:
1540 xt_free_table_info(newinfo);
1541 return ret;
1542}
1543
1544static int compat_do_arpt_set_ctl(struct sock *sk, int cmd, void __user *user,
1545 unsigned int len)
1546{
1547 int ret;
1548
1549 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
1550 return -EPERM;
1551
1552 switch (cmd) {
1553 case ARPT_SO_SET_REPLACE:
1554 ret = compat_do_replace(sock_net(sk), user, len);
1555 break;
1556
1557 case ARPT_SO_SET_ADD_COUNTERS:
1558 ret = do_add_counters(sock_net(sk), user, len, 1);
1559 break;
1560
1561 default:
1562 duprintf("do_arpt_set_ctl: unknown request %i\n", cmd);
1563 ret = -EINVAL;
1564 }
1565
1566 return ret;
1567}
1568
1569static int compat_copy_entry_to_user(struct arpt_entry *e, void __user **dstptr,
1570 compat_uint_t *size,
1571 struct xt_counters *counters,
1572 unsigned int i)
1573{
1574 struct xt_entry_target *t;
1575 struct compat_arpt_entry __user *ce;
1576 u_int16_t target_offset, next_offset;
1577 compat_uint_t origsize;
1578 int ret;
1579
1580 origsize = *size;
1581 ce = (struct compat_arpt_entry __user *)*dstptr;
1582 if (copy_to_user(ce, e, sizeof(struct arpt_entry)) != 0 ||
1583 copy_to_user(&ce->counters, &counters[i],
1584 sizeof(counters[i])) != 0)
1585 return -EFAULT;
1586
1587 *dstptr += sizeof(struct compat_arpt_entry);
1588 *size -= sizeof(struct arpt_entry) - sizeof(struct compat_arpt_entry);
1589
1590 target_offset = e->target_offset - (origsize - *size);
1591
1592 t = arpt_get_target(e);
1593 ret = xt_compat_target_to_user(t, dstptr, size);
1594 if (ret)
1595 return ret;
1596 next_offset = e->next_offset - (origsize - *size);
1597 if (put_user(target_offset, &ce->target_offset) != 0 ||
1598 put_user(next_offset, &ce->next_offset) != 0)
1599 return -EFAULT;
1600 return 0;
1601}
1602
1603static int compat_copy_entries_to_user(unsigned int total_size,
1604 struct xt_table *table,
1605 void __user *userptr)
1606{
1607 struct xt_counters *counters;
1608 const struct xt_table_info *private = table->private;
1609 void __user *pos;
1610 unsigned int size;
1611 int ret = 0;
1612 void *loc_cpu_entry;
1613 unsigned int i = 0;
1614 struct arpt_entry *iter;
1615
1616 counters = alloc_counters(table);
1617 if (IS_ERR(counters))
1618 return PTR_ERR(counters);
1619
1620
1621 loc_cpu_entry = private->entries[raw_smp_processor_id()];
1622 pos = userptr;
1623 size = total_size;
1624 xt_entry_foreach(iter, loc_cpu_entry, total_size) {
1625 ret = compat_copy_entry_to_user(iter, &pos,
1626 &size, counters, i++);
1627 if (ret != 0)
1628 break;
1629 }
1630 vfree(counters);
1631 return ret;
1632}
1633
1634struct compat_arpt_get_entries {
1635 char name[XT_TABLE_MAXNAMELEN];
1636 compat_uint_t size;
1637 struct compat_arpt_entry entrytable[0];
1638};
1639
1640static int compat_get_entries(struct net *net,
1641 struct compat_arpt_get_entries __user *uptr,
1642 int *len)
1643{
1644 int ret;
1645 struct compat_arpt_get_entries get;
1646 struct xt_table *t;
1647
1648 if (*len < sizeof(get)) {
1649 duprintf("compat_get_entries: %u < %zu\n", *len, sizeof(get));
1650 return -EINVAL;
1651 }
1652 if (copy_from_user(&get, uptr, sizeof(get)) != 0)
1653 return -EFAULT;
1654 if (*len != sizeof(struct compat_arpt_get_entries) + get.size) {
1655 duprintf("compat_get_entries: %u != %zu\n",
1656 *len, sizeof(get) + get.size);
1657 return -EINVAL;
1658 }
1659
1660 xt_compat_lock(NFPROTO_ARP);
1661 t = xt_find_table_lock(net, NFPROTO_ARP, get.name);
1662 if (!IS_ERR_OR_NULL(t)) {
1663 const struct xt_table_info *private = t->private;
1664 struct xt_table_info info;
1665
1666 duprintf("t->private->number = %u\n", private->number);
1667 ret = compat_table_info(private, &info);
1668 if (!ret && get.size == info.size) {
1669 ret = compat_copy_entries_to_user(private->size,
1670 t, uptr->entrytable);
1671 } else if (!ret) {
1672 duprintf("compat_get_entries: I've got %u not %u!\n",
1673 private->size, get.size);
1674 ret = -EAGAIN;
1675 }
1676 xt_compat_flush_offsets(NFPROTO_ARP);
1677 module_put(t->me);
1678 xt_table_unlock(t);
1679 } else
1680 ret = t ? PTR_ERR(t) : -ENOENT;
1681
1682 xt_compat_unlock(NFPROTO_ARP);
1683 return ret;
1684}
1685
1686static int do_arpt_get_ctl(struct sock *, int, void __user *, int *);
1687
1688static int compat_do_arpt_get_ctl(struct sock *sk, int cmd, void __user *user,
1689 int *len)
1690{
1691 int ret;
1692
1693 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
1694 return -EPERM;
1695
1696 switch (cmd) {
1697 case ARPT_SO_GET_INFO:
1698 ret = get_info(sock_net(sk), user, len, 1);
1699 break;
1700 case ARPT_SO_GET_ENTRIES:
1701 ret = compat_get_entries(sock_net(sk), user, len);
1702 break;
1703 default:
1704 ret = do_arpt_get_ctl(sk, cmd, user, len);
1705 }
1706 return ret;
1707}
1708#endif
1709
1710static int do_arpt_set_ctl(struct sock *sk, int cmd, void __user *user, unsigned int len)
1711{
1712 int ret;
1713
1714 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
1715 return -EPERM;
1716
1717 switch (cmd) {
1718 case ARPT_SO_SET_REPLACE:
1719 ret = do_replace(sock_net(sk), user, len);
1720 break;
1721
1722 case ARPT_SO_SET_ADD_COUNTERS:
1723 ret = do_add_counters(sock_net(sk), user, len, 0);
1724 break;
1725
1726 default:
1727 duprintf("do_arpt_set_ctl: unknown request %i\n", cmd);
1728 ret = -EINVAL;
1729 }
1730
1731 return ret;
1732}
1733
1734static int do_arpt_get_ctl(struct sock *sk, int cmd, void __user *user, int *len)
1735{
1736 int ret;
1737
1738 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
1739 return -EPERM;
1740
1741 switch (cmd) {
1742 case ARPT_SO_GET_INFO:
1743 ret = get_info(sock_net(sk), user, len, 0);
1744 break;
1745
1746 case ARPT_SO_GET_ENTRIES:
1747 ret = get_entries(sock_net(sk), user, len);
1748 break;
1749
1750 case ARPT_SO_GET_REVISION_TARGET: {
1751 struct xt_get_revision rev;
1752
1753 if (*len != sizeof(rev)) {
1754 ret = -EINVAL;
1755 break;
1756 }
1757 if (copy_from_user(&rev, user, sizeof(rev)) != 0) {
1758 ret = -EFAULT;
1759 break;
1760 }
1761 rev.name[sizeof(rev.name)-1] = 0;
1762
1763 try_then_request_module(xt_find_revision(NFPROTO_ARP, rev.name,
1764 rev.revision, 1, &ret),
1765 "arpt_%s", rev.name);
1766 break;
1767 }
1768
1769 default:
1770 duprintf("do_arpt_get_ctl: unknown request %i\n", cmd);
1771 ret = -EINVAL;
1772 }
1773
1774 return ret;
1775}
1776
1777struct xt_table *arpt_register_table(struct net *net,
1778 const struct xt_table *table,
1779 const struct arpt_replace *repl)
1780{
1781 int ret;
1782 struct xt_table_info *newinfo;
1783 struct xt_table_info bootstrap = {0};
1784 void *loc_cpu_entry;
1785 struct xt_table *new_table;
1786
1787 newinfo = xt_alloc_table_info(repl->size);
1788 if (!newinfo) {
1789 ret = -ENOMEM;
1790 goto out;
1791 }
1792
1793
1794 loc_cpu_entry = newinfo->entries[raw_smp_processor_id()];
1795 memcpy(loc_cpu_entry, repl->entries, repl->size);
1796
1797 ret = translate_table(newinfo, loc_cpu_entry, repl);
1798 duprintf("arpt_register_table: translate table gives %d\n", ret);
1799 if (ret != 0)
1800 goto out_free;
1801
1802 new_table = xt_register_table(net, table, &bootstrap, newinfo);
1803 if (IS_ERR(new_table)) {
1804 ret = PTR_ERR(new_table);
1805 goto out_free;
1806 }
1807 return new_table;
1808
1809out_free:
1810 xt_free_table_info(newinfo);
1811out:
1812 return ERR_PTR(ret);
1813}
1814
1815void arpt_unregister_table(struct xt_table *table)
1816{
1817 struct xt_table_info *private;
1818 void *loc_cpu_entry;
1819 struct module *table_owner = table->me;
1820 struct arpt_entry *iter;
1821
1822 private = xt_unregister_table(table);
1823
1824
1825 loc_cpu_entry = private->entries[raw_smp_processor_id()];
1826 xt_entry_foreach(iter, loc_cpu_entry, private->size)
1827 cleanup_entry(iter);
1828 if (private->number > private->initial_entries)
1829 module_put(table_owner);
1830 xt_free_table_info(private);
1831}
1832
1833
1834static struct xt_target arpt_builtin_tg[] __read_mostly = {
1835 {
1836 .name = XT_STANDARD_TARGET,
1837 .targetsize = sizeof(int),
1838 .family = NFPROTO_ARP,
1839#ifdef CONFIG_COMPAT
1840 .compatsize = sizeof(compat_int_t),
1841 .compat_from_user = compat_standard_from_user,
1842 .compat_to_user = compat_standard_to_user,
1843#endif
1844 },
1845 {
1846 .name = XT_ERROR_TARGET,
1847 .target = arpt_error,
1848 .targetsize = XT_FUNCTION_MAXNAMELEN,
1849 .family = NFPROTO_ARP,
1850 },
1851};
1852
1853static struct nf_sockopt_ops arpt_sockopts = {
1854 .pf = PF_INET,
1855 .set_optmin = ARPT_BASE_CTL,
1856 .set_optmax = ARPT_SO_SET_MAX+1,
1857 .set = do_arpt_set_ctl,
1858#ifdef CONFIG_COMPAT
1859 .compat_set = compat_do_arpt_set_ctl,
1860#endif
1861 .get_optmin = ARPT_BASE_CTL,
1862 .get_optmax = ARPT_SO_GET_MAX+1,
1863 .get = do_arpt_get_ctl,
1864#ifdef CONFIG_COMPAT
1865 .compat_get = compat_do_arpt_get_ctl,
1866#endif
1867 .owner = THIS_MODULE,
1868};
1869
1870static int __net_init arp_tables_net_init(struct net *net)
1871{
1872 return xt_proto_init(net, NFPROTO_ARP);
1873}
1874
1875static void __net_exit arp_tables_net_exit(struct net *net)
1876{
1877 xt_proto_fini(net, NFPROTO_ARP);
1878}
1879
1880static struct pernet_operations arp_tables_net_ops = {
1881 .init = arp_tables_net_init,
1882 .exit = arp_tables_net_exit,
1883};
1884
1885static int __init arp_tables_init(void)
1886{
1887 int ret;
1888
1889 ret = register_pernet_subsys(&arp_tables_net_ops);
1890 if (ret < 0)
1891 goto err1;
1892
1893
1894 ret = xt_register_targets(arpt_builtin_tg, ARRAY_SIZE(arpt_builtin_tg));
1895 if (ret < 0)
1896 goto err2;
1897
1898
1899 ret = nf_register_sockopt(&arpt_sockopts);
1900 if (ret < 0)
1901 goto err4;
1902
1903 printk(KERN_INFO "arp_tables: (C) 2002 David S. Miller\n");
1904 return 0;
1905
1906err4:
1907 xt_unregister_targets(arpt_builtin_tg, ARRAY_SIZE(arpt_builtin_tg));
1908err2:
1909 unregister_pernet_subsys(&arp_tables_net_ops);
1910err1:
1911 return ret;
1912}
1913
1914static void __exit arp_tables_fini(void)
1915{
1916 nf_unregister_sockopt(&arpt_sockopts);
1917 xt_unregister_targets(arpt_builtin_tg, ARRAY_SIZE(arpt_builtin_tg));
1918 unregister_pernet_subsys(&arp_tables_net_ops);
1919}
1920
1921EXPORT_SYMBOL(arpt_register_table);
1922EXPORT_SYMBOL(arpt_unregister_table);
1923EXPORT_SYMBOL(arpt_do_table);
1924
1925module_init(arp_tables_init);
1926module_exit(arp_tables_fini);
1927
