2 * Packet matching code for ARP packets.
4 * Based heavily, if not almost entirely, upon ip_tables.c framework.
6 * Some ARP specific bits are:
8 * Copyright (C) 2002 David S. Miller (davem@redhat.com)
9 * Copyright (C) 2006-2009 Patrick McHardy <kaber@trash.net>
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>
27 #include <asm/uaccess.h>
29 #include <linux/netfilter/x_tables.h>
30 #include <linux/netfilter_arp/arp_tables.h>
31 #include "../../netfilter/xt_repldata.h"
33 MODULE_LICENSE("GPL");
34 MODULE_AUTHOR("David S. Miller <davem@redhat.com>");
35 MODULE_DESCRIPTION("arptables core");
37 /*#define DEBUG_ARP_TABLES*/
38 /*#define DEBUG_ARP_TABLES_USER*/
40 #ifdef DEBUG_ARP_TABLES
41 #define dprintf(format, args...) printk(format , ## args)
43 #define dprintf(format, args...)
46 #ifdef DEBUG_ARP_TABLES_USER
47 #define duprintf(format, args...) printk(format , ## args)
49 #define duprintf(format, args...)
52 #ifdef CONFIG_NETFILTER_DEBUG
53 #define ARP_NF_ASSERT(x) WARN_ON(!(x))
55 #define ARP_NF_ASSERT(x)
58 void *arpt_alloc_initial_table(const struct xt_table *info)
60 return xt_alloc_initial_table(arpt, ARPT);
62 EXPORT_SYMBOL_GPL(arpt_alloc_initial_table);
64 static inline int arp_devaddr_compare(const struct arpt_devaddr_info *ap,
65 const char *hdr_addr, int len)
69 if (len > ARPT_DEV_ADDR_LEN_MAX)
70 len = ARPT_DEV_ADDR_LEN_MAX;
73 for (i = 0; i < len; i++)
74 ret |= (hdr_addr[i] ^ ap->addr[i]) & ap->mask[i];
80 * Unfortunately, _b and _mask are not aligned to an int (or long int)
81 * Some arches dont care, unrolling the loop is a win on them.
82 * For other arches, we only have a 16bit alignement.
84 static unsigned long ifname_compare(const char *_a, const char *_b, const char *_mask)
86 #ifdef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
87 unsigned long ret = ifname_compare_aligned(_a, _b, _mask);
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;
95 for (i = 0; i < IFNAMSIZ/sizeof(u16); i++)
96 ret |= (a[i] ^ b[i]) & mask[i];
101 /* Returns whether packet matches rule or not. */
102 static inline int arp_packet_match(const struct arphdr *arphdr,
103 struct net_device *dev,
106 const struct arpt_arp *arpinfo)
108 const char *arpptr = (char *)(arphdr + 1);
109 const char *src_devaddr, *tgt_devaddr;
110 __be32 src_ipaddr, tgt_ipaddr;
113 #define FWINV(bool, invflg) ((bool) ^ !!(arpinfo->invflags & (invflg)))
115 if (FWINV((arphdr->ar_op & arpinfo->arpop_mask) != arpinfo->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);
123 if (FWINV((arphdr->ar_hrd & arpinfo->arhrd_mask) != arpinfo->arhrd,
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);
131 if (FWINV((arphdr->ar_pro & arpinfo->arpro_mask) != arpinfo->arpro,
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);
139 if (FWINV((arphdr->ar_hln & arpinfo->arhln_mask) != arpinfo->arhln,
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);
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));
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");
164 if (FWINV((src_ipaddr & arpinfo->smsk.s_addr) != arpinfo->src.s_addr,
166 FWINV(((tgt_ipaddr & arpinfo->tmsk.s_addr) != arpinfo->tgt.s_addr),
168 dprintf("Source or target IP address mismatch.\n");
170 dprintf("SRC: %pI4. Mask: %pI4. Target: %pI4.%s\n",
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",
177 &arpinfo->tmsk.s_addr,
178 &arpinfo->tgt.s_addr,
179 arpinfo->invflags & ARPT_INV_TGTIP ? " (INV)" : "");
183 /* Look for ifname matches. */
184 ret = ifname_compare(indev, arpinfo->iniface, arpinfo->iniface_mask);
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)":"");
193 ret = ifname_compare(outdev, arpinfo->outiface, arpinfo->outiface_mask);
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)":"");
206 static inline int arp_checkentry(const struct arpt_arp *arp)
208 if (arp->flags & ~ARPT_F_MASK) {
209 duprintf("Unknown flag bits set: %08X\n",
210 arp->flags & ~ARPT_F_MASK);
213 if (arp->invflags & ~ARPT_INV_MASK) {
214 duprintf("Unknown invflag bits set: %08X\n",
215 arp->invflags & ~ARPT_INV_MASK);
223 arpt_error(struct sk_buff *skb, const struct xt_action_param *par)
225 net_err_ratelimited("arp_tables: error: '%s'\n",
226 (const char *)par->targinfo);
231 static inline const struct xt_entry_target *
232 arpt_get_target_c(const struct arpt_entry *e)
234 return arpt_get_target((struct arpt_entry *)e);
237 static inline struct arpt_entry *
238 get_entry(const void *base, unsigned int offset)
240 return (struct arpt_entry *)(base + offset);
244 struct arpt_entry *arpt_next_entry(const struct arpt_entry *entry)
246 return (void *)entry + entry->next_offset;
249 unsigned int arpt_do_table(struct sk_buff *skb,
251 const struct nf_hook_state *state,
252 struct xt_table *table)
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 const void *table_base;
260 const struct xt_table_info *private;
261 struct xt_action_param acpar;
264 if (!pskb_may_pull(skb, arp_hdr_len(skb->dev)))
267 indev = state->in ? state->in->name : nulldevname;
268 outdev = state->out ? state->out->name : nulldevname;
271 addend = xt_write_recseq_begin();
272 private = table->private;
274 * Ensure we load private-> members after we've fetched the base
277 smp_read_barrier_depends();
278 table_base = private->entries;
280 e = get_entry(table_base, private->hook_entry[hook]);
281 back = get_entry(table_base, private->underflow[hook]);
283 acpar.in = state->in;
284 acpar.out = state->out;
285 acpar.hooknum = hook;
286 acpar.family = NFPROTO_ARP;
287 acpar.hotdrop = false;
291 const struct xt_entry_target *t;
292 struct xt_counters *counter;
294 if (!arp_packet_match(arp, skb->dev, indev, outdev, &e->arp)) {
295 e = arpt_next_entry(e);
299 counter = xt_get_this_cpu_counter(&e->counters);
300 ADD_COUNTER(*counter, arp_hdr_len(skb->dev), 1);
302 t = arpt_get_target_c(e);
304 /* Standard target? */
305 if (!t->u.kernel.target->target) {
308 v = ((struct xt_standard_target *)t)->verdict;
310 /* Pop from stack? */
311 if (v != XT_RETURN) {
312 verdict = (unsigned int)(-v) - 1;
316 back = get_entry(table_base, back->comefrom);
320 != arpt_next_entry(e)) {
321 /* Save old back ptr in next entry */
322 struct arpt_entry *next = arpt_next_entry(e);
323 next->comefrom = (void *)back - table_base;
325 /* set back pointer to next entry */
329 e = get_entry(table_base, v);
333 /* Targets which reenter must return
336 acpar.target = t->u.kernel.target;
337 acpar.targinfo = t->data;
338 verdict = t->u.kernel.target->target(skb, &acpar);
340 /* Target might have changed stuff. */
343 if (verdict == XT_CONTINUE)
344 e = arpt_next_entry(e);
348 } while (!acpar.hotdrop);
349 xt_write_recseq_end(addend);
358 /* All zeroes == unconditional rule. */
359 static inline bool unconditional(const struct arpt_arp *arp)
361 static const struct arpt_arp uncond;
363 return memcmp(arp, &uncond, sizeof(uncond)) == 0;
366 /* Figures out from what hook each rule can be called: returns 0 if
367 * there are loops. Puts hook bitmask in comefrom.
369 static int mark_source_chains(const struct xt_table_info *newinfo,
370 unsigned int valid_hooks, void *entry0)
374 /* No recursion; use packet counter to save back ptrs (reset
375 * to 0 as we leave), and comefrom to save source hook bitmask.
377 for (hook = 0; hook < NF_ARP_NUMHOOKS; hook++) {
378 unsigned int pos = newinfo->hook_entry[hook];
380 = (struct arpt_entry *)(entry0 + pos);
382 if (!(valid_hooks & (1 << hook)))
385 /* Set initial back pointer. */
386 e->counters.pcnt = pos;
389 const struct xt_standard_target *t
390 = (void *)arpt_get_target_c(e);
391 int visited = e->comefrom & (1 << hook);
393 if (e->comefrom & (1 << NF_ARP_NUMHOOKS)) {
394 pr_notice("arptables: loop hook %u pos %u %08X.\n",
395 hook, pos, e->comefrom);
399 |= ((1 << hook) | (1 << NF_ARP_NUMHOOKS));
401 /* Unconditional return/END. */
402 if ((e->target_offset == sizeof(struct arpt_entry) &&
403 (strcmp(t->target.u.user.name,
404 XT_STANDARD_TARGET) == 0) &&
405 t->verdict < 0 && unconditional(&e->arp)) ||
407 unsigned int oldpos, size;
409 if ((strcmp(t->target.u.user.name,
410 XT_STANDARD_TARGET) == 0) &&
411 t->verdict < -NF_MAX_VERDICT - 1) {
412 duprintf("mark_source_chains: bad "
413 "negative verdict (%i)\n",
418 /* Return: backtrack through the last
422 e->comefrom ^= (1<<NF_ARP_NUMHOOKS);
424 pos = e->counters.pcnt;
425 e->counters.pcnt = 0;
427 /* We're at the start. */
431 e = (struct arpt_entry *)
433 } while (oldpos == pos + e->next_offset);
436 size = e->next_offset;
437 e = (struct arpt_entry *)
438 (entry0 + pos + size);
439 e->counters.pcnt = pos;
442 int newpos = t->verdict;
444 if (strcmp(t->target.u.user.name,
445 XT_STANDARD_TARGET) == 0 &&
447 if (newpos > newinfo->size -
448 sizeof(struct arpt_entry)) {
449 duprintf("mark_source_chains: "
450 "bad verdict (%i)\n",
455 /* This a jump; chase it. */
456 duprintf("Jump rule %u -> %u\n",
459 /* ... this is a fallthru */
460 newpos = pos + e->next_offset;
462 e = (struct arpt_entry *)
464 e->counters.pcnt = pos;
469 duprintf("Finished chain %u\n", hook);
474 static inline int check_entry(const struct arpt_entry *e, const char *name)
476 const struct xt_entry_target *t;
478 if (!arp_checkentry(&e->arp)) {
479 duprintf("arp_tables: arp check failed %p %s.\n", e, name);
483 if (e->target_offset + sizeof(struct xt_entry_target) > e->next_offset)
486 t = arpt_get_target_c(e);
487 if (e->target_offset + t->u.target_size > e->next_offset)
493 static inline int check_target(struct arpt_entry *e, const char *name)
495 struct xt_entry_target *t = arpt_get_target(e);
497 struct xt_tgchk_param par = {
500 .target = t->u.kernel.target,
502 .hook_mask = e->comefrom,
503 .family = NFPROTO_ARP,
506 ret = xt_check_target(&par, t->u.target_size - sizeof(*t), 0, false);
508 duprintf("arp_tables: check failed for `%s'.\n",
509 t->u.kernel.target->name);
516 find_check_entry(struct arpt_entry *e, const char *name, unsigned int size)
518 struct xt_entry_target *t;
519 struct xt_target *target;
522 ret = check_entry(e, name);
526 e->counters.pcnt = xt_percpu_counter_alloc();
527 if (IS_ERR_VALUE(e->counters.pcnt))
530 t = arpt_get_target(e);
531 target = xt_request_find_target(NFPROTO_ARP, t->u.user.name,
533 if (IS_ERR(target)) {
534 duprintf("find_check_entry: `%s' not found\n", t->u.user.name);
535 ret = PTR_ERR(target);
538 t->u.kernel.target = target;
540 ret = check_target(e, name);
545 module_put(t->u.kernel.target->me);
547 xt_percpu_counter_free(e->counters.pcnt);
552 static bool check_underflow(const struct arpt_entry *e)
554 const struct xt_entry_target *t;
555 unsigned int verdict;
557 if (!unconditional(&e->arp))
559 t = arpt_get_target_c(e);
560 if (strcmp(t->u.user.name, XT_STANDARD_TARGET) != 0)
562 verdict = ((struct xt_standard_target *)t)->verdict;
563 verdict = -verdict - 1;
564 return verdict == NF_DROP || verdict == NF_ACCEPT;
567 static inline int check_entry_size_and_hooks(struct arpt_entry *e,
568 struct xt_table_info *newinfo,
569 const unsigned char *base,
570 const unsigned char *limit,
571 const unsigned int *hook_entries,
572 const unsigned int *underflows,
573 unsigned int valid_hooks)
577 if ((unsigned long)e % __alignof__(struct arpt_entry) != 0 ||
578 (unsigned char *)e + sizeof(struct arpt_entry) >= limit) {
579 duprintf("Bad offset %p\n", e);
584 < sizeof(struct arpt_entry) + sizeof(struct xt_entry_target)) {
585 duprintf("checking: element %p size %u\n",
590 /* Check hooks & underflows */
591 for (h = 0; h < NF_ARP_NUMHOOKS; h++) {
592 if (!(valid_hooks & (1 << h)))
594 if ((unsigned char *)e - base == hook_entries[h])
595 newinfo->hook_entry[h] = hook_entries[h];
596 if ((unsigned char *)e - base == underflows[h]) {
597 if (!check_underflow(e)) {
598 pr_err("Underflows must be unconditional and "
599 "use the STANDARD target with "
603 newinfo->underflow[h] = underflows[h];
607 /* Clear counters and comefrom */
608 e->counters = ((struct xt_counters) { 0, 0 });
613 static inline void cleanup_entry(struct arpt_entry *e)
615 struct xt_tgdtor_param par;
616 struct xt_entry_target *t;
618 t = arpt_get_target(e);
619 par.target = t->u.kernel.target;
620 par.targinfo = t->data;
621 par.family = NFPROTO_ARP;
622 if (par.target->destroy != NULL)
623 par.target->destroy(&par);
624 module_put(par.target->me);
625 xt_percpu_counter_free(e->counters.pcnt);
628 /* Checks and translates the user-supplied table segment (held in
631 static int translate_table(struct xt_table_info *newinfo, void *entry0,
632 const struct arpt_replace *repl)
634 struct arpt_entry *iter;
638 newinfo->size = repl->size;
639 newinfo->number = repl->num_entries;
641 /* Init all hooks to impossible value. */
642 for (i = 0; i < NF_ARP_NUMHOOKS; i++) {
643 newinfo->hook_entry[i] = 0xFFFFFFFF;
644 newinfo->underflow[i] = 0xFFFFFFFF;
647 duprintf("translate_table: size %u\n", newinfo->size);
650 /* Walk through entries, checking offsets. */
651 xt_entry_foreach(iter, entry0, newinfo->size) {
652 ret = check_entry_size_and_hooks(iter, newinfo, entry0,
660 if (strcmp(arpt_get_target(iter)->u.user.name,
661 XT_ERROR_TARGET) == 0)
662 ++newinfo->stacksize;
664 duprintf("translate_table: ARPT_ENTRY_ITERATE gives %d\n", ret);
668 if (i != repl->num_entries) {
669 duprintf("translate_table: %u not %u entries\n",
670 i, repl->num_entries);
674 /* Check hooks all assigned */
675 for (i = 0; i < NF_ARP_NUMHOOKS; i++) {
676 /* Only hooks which are valid */
677 if (!(repl->valid_hooks & (1 << i)))
679 if (newinfo->hook_entry[i] == 0xFFFFFFFF) {
680 duprintf("Invalid hook entry %u %u\n",
681 i, repl->hook_entry[i]);
684 if (newinfo->underflow[i] == 0xFFFFFFFF) {
685 duprintf("Invalid underflow %u %u\n",
686 i, repl->underflow[i]);
691 if (!mark_source_chains(newinfo, repl->valid_hooks, entry0)) {
692 duprintf("Looping hook\n");
696 /* Finally, each sanity check must pass */
698 xt_entry_foreach(iter, entry0, newinfo->size) {
699 ret = find_check_entry(iter, repl->name, repl->size);
706 xt_entry_foreach(iter, entry0, newinfo->size) {
717 static void get_counters(const struct xt_table_info *t,
718 struct xt_counters counters[])
720 struct arpt_entry *iter;
724 for_each_possible_cpu(cpu) {
725 seqcount_t *s = &per_cpu(xt_recseq, cpu);
728 xt_entry_foreach(iter, t->entries, t->size) {
729 struct xt_counters *tmp;
733 tmp = xt_get_per_cpu_counter(&iter->counters, cpu);
735 start = read_seqcount_begin(s);
738 } while (read_seqcount_retry(s, start));
740 ADD_COUNTER(counters[i], bcnt, pcnt);
746 static struct xt_counters *alloc_counters(const struct xt_table *table)
748 unsigned int countersize;
749 struct xt_counters *counters;
750 const struct xt_table_info *private = table->private;
752 /* We need atomic snapshot of counters: rest doesn't change
753 * (other than comefrom, which userspace doesn't care
756 countersize = sizeof(struct xt_counters) * private->number;
757 counters = vzalloc(countersize);
759 if (counters == NULL)
760 return ERR_PTR(-ENOMEM);
762 get_counters(private, counters);
767 static int copy_entries_to_user(unsigned int total_size,
768 const struct xt_table *table,
769 void __user *userptr)
771 unsigned int off, num;
772 const struct arpt_entry *e;
773 struct xt_counters *counters;
774 struct xt_table_info *private = table->private;
778 counters = alloc_counters(table);
779 if (IS_ERR(counters))
780 return PTR_ERR(counters);
782 loc_cpu_entry = private->entries;
783 /* ... then copy entire thing ... */
784 if (copy_to_user(userptr, loc_cpu_entry, total_size) != 0) {
789 /* FIXME: use iterator macros --RR */
790 /* ... then go back and fix counters and names */
791 for (off = 0, num = 0; off < total_size; off += e->next_offset, num++){
792 const struct xt_entry_target *t;
794 e = (struct arpt_entry *)(loc_cpu_entry + off);
795 if (copy_to_user(userptr + off
796 + offsetof(struct arpt_entry, counters),
798 sizeof(counters[num])) != 0) {
803 t = arpt_get_target_c(e);
804 if (copy_to_user(userptr + off + e->target_offset
805 + offsetof(struct xt_entry_target,
807 t->u.kernel.target->name,
808 strlen(t->u.kernel.target->name)+1) != 0) {
820 static void compat_standard_from_user(void *dst, const void *src)
822 int v = *(compat_int_t *)src;
825 v += xt_compat_calc_jump(NFPROTO_ARP, v);
826 memcpy(dst, &v, sizeof(v));
829 static int compat_standard_to_user(void __user *dst, const void *src)
831 compat_int_t cv = *(int *)src;
834 cv -= xt_compat_calc_jump(NFPROTO_ARP, cv);
835 return copy_to_user(dst, &cv, sizeof(cv)) ? -EFAULT : 0;
838 static int compat_calc_entry(const struct arpt_entry *e,
839 const struct xt_table_info *info,
840 const void *base, struct xt_table_info *newinfo)
842 const struct xt_entry_target *t;
843 unsigned int entry_offset;
846 off = sizeof(struct arpt_entry) - sizeof(struct compat_arpt_entry);
847 entry_offset = (void *)e - base;
849 t = arpt_get_target_c(e);
850 off += xt_compat_target_offset(t->u.kernel.target);
851 newinfo->size -= off;
852 ret = xt_compat_add_offset(NFPROTO_ARP, entry_offset, off);
856 for (i = 0; i < NF_ARP_NUMHOOKS; i++) {
857 if (info->hook_entry[i] &&
858 (e < (struct arpt_entry *)(base + info->hook_entry[i])))
859 newinfo->hook_entry[i] -= off;
860 if (info->underflow[i] &&
861 (e < (struct arpt_entry *)(base + info->underflow[i])))
862 newinfo->underflow[i] -= off;
867 static int compat_table_info(const struct xt_table_info *info,
868 struct xt_table_info *newinfo)
870 struct arpt_entry *iter;
871 const void *loc_cpu_entry;
874 if (!newinfo || !info)
877 /* we dont care about newinfo->entries */
878 memcpy(newinfo, info, offsetof(struct xt_table_info, entries));
879 newinfo->initial_entries = 0;
880 loc_cpu_entry = info->entries;
881 xt_compat_init_offsets(NFPROTO_ARP, info->number);
882 xt_entry_foreach(iter, loc_cpu_entry, info->size) {
883 ret = compat_calc_entry(iter, info, loc_cpu_entry, newinfo);
891 static int get_info(struct net *net, void __user *user,
892 const int *len, int compat)
894 char name[XT_TABLE_MAXNAMELEN];
898 if (*len != sizeof(struct arpt_getinfo)) {
899 duprintf("length %u != %Zu\n", *len,
900 sizeof(struct arpt_getinfo));
904 if (copy_from_user(name, user, sizeof(name)) != 0)
907 name[XT_TABLE_MAXNAMELEN-1] = '\0';
910 xt_compat_lock(NFPROTO_ARP);
912 t = try_then_request_module(xt_find_table_lock(net, NFPROTO_ARP, name),
913 "arptable_%s", name);
914 if (!IS_ERR_OR_NULL(t)) {
915 struct arpt_getinfo info;
916 const struct xt_table_info *private = t->private;
918 struct xt_table_info tmp;
921 ret = compat_table_info(private, &tmp);
922 xt_compat_flush_offsets(NFPROTO_ARP);
926 memset(&info, 0, sizeof(info));
927 info.valid_hooks = t->valid_hooks;
928 memcpy(info.hook_entry, private->hook_entry,
929 sizeof(info.hook_entry));
930 memcpy(info.underflow, private->underflow,
931 sizeof(info.underflow));
932 info.num_entries = private->number;
933 info.size = private->size;
934 strcpy(info.name, name);
936 if (copy_to_user(user, &info, *len) != 0)
943 ret = t ? PTR_ERR(t) : -ENOENT;
946 xt_compat_unlock(NFPROTO_ARP);
951 static int get_entries(struct net *net, struct arpt_get_entries __user *uptr,
955 struct arpt_get_entries get;
958 if (*len < sizeof(get)) {
959 duprintf("get_entries: %u < %Zu\n", *len, sizeof(get));
962 if (copy_from_user(&get, uptr, sizeof(get)) != 0)
964 if (*len != sizeof(struct arpt_get_entries) + get.size) {
965 duprintf("get_entries: %u != %Zu\n", *len,
966 sizeof(struct arpt_get_entries) + get.size);
970 t = xt_find_table_lock(net, NFPROTO_ARP, get.name);
971 if (!IS_ERR_OR_NULL(t)) {
972 const struct xt_table_info *private = t->private;
974 duprintf("t->private->number = %u\n",
976 if (get.size == private->size)
977 ret = copy_entries_to_user(private->size,
978 t, uptr->entrytable);
980 duprintf("get_entries: I've got %u not %u!\n",
981 private->size, get.size);
987 ret = t ? PTR_ERR(t) : -ENOENT;
992 static int __do_replace(struct net *net, const char *name,
993 unsigned int valid_hooks,
994 struct xt_table_info *newinfo,
995 unsigned int num_counters,
996 void __user *counters_ptr)
1000 struct xt_table_info *oldinfo;
1001 struct xt_counters *counters;
1002 void *loc_cpu_old_entry;
1003 struct arpt_entry *iter;
1006 counters = vzalloc(num_counters * sizeof(struct xt_counters));
1012 t = try_then_request_module(xt_find_table_lock(net, NFPROTO_ARP, name),
1013 "arptable_%s", name);
1014 if (IS_ERR_OR_NULL(t)) {
1015 ret = t ? PTR_ERR(t) : -ENOENT;
1016 goto free_newinfo_counters_untrans;
1020 if (valid_hooks != t->valid_hooks) {
1021 duprintf("Valid hook crap: %08X vs %08X\n",
1022 valid_hooks, t->valid_hooks);
1027 oldinfo = xt_replace_table(t, num_counters, newinfo, &ret);
1031 /* Update module usage count based on number of rules */
1032 duprintf("do_replace: oldnum=%u, initnum=%u, newnum=%u\n",
1033 oldinfo->number, oldinfo->initial_entries, newinfo->number);
1034 if ((oldinfo->number > oldinfo->initial_entries) ||
1035 (newinfo->number <= oldinfo->initial_entries))
1037 if ((oldinfo->number > oldinfo->initial_entries) &&
1038 (newinfo->number <= oldinfo->initial_entries))
1041 /* Get the old counters, and synchronize with replace */
1042 get_counters(oldinfo, counters);
1044 /* Decrease module usage counts and free resource */
1045 loc_cpu_old_entry = oldinfo->entries;
1046 xt_entry_foreach(iter, loc_cpu_old_entry, oldinfo->size)
1047 cleanup_entry(iter);
1049 xt_free_table_info(oldinfo);
1050 if (copy_to_user(counters_ptr, counters,
1051 sizeof(struct xt_counters) * num_counters) != 0) {
1052 /* Silent error, can't fail, new table is already in place */
1053 net_warn_ratelimited("arptables: counters copy to user failed while replacing table\n");
1062 free_newinfo_counters_untrans:
1068 static int do_replace(struct net *net, const void __user *user,
1072 struct arpt_replace tmp;
1073 struct xt_table_info *newinfo;
1074 void *loc_cpu_entry;
1075 struct arpt_entry *iter;
1077 if (copy_from_user(&tmp, user, sizeof(tmp)) != 0)
1080 /* overflow check */
1081 if (tmp.num_counters >= INT_MAX / sizeof(struct xt_counters))
1083 if (tmp.num_counters == 0)
1086 tmp.name[sizeof(tmp.name)-1] = 0;
1088 newinfo = xt_alloc_table_info(tmp.size);
1092 loc_cpu_entry = newinfo->entries;
1093 if (copy_from_user(loc_cpu_entry, user + sizeof(tmp),
1099 ret = translate_table(newinfo, loc_cpu_entry, &tmp);
1103 duprintf("arp_tables: Translated table\n");
1105 ret = __do_replace(net, tmp.name, tmp.valid_hooks, newinfo,
1106 tmp.num_counters, tmp.counters);
1108 goto free_newinfo_untrans;
1111 free_newinfo_untrans:
1112 xt_entry_foreach(iter, loc_cpu_entry, newinfo->size)
1113 cleanup_entry(iter);
1115 xt_free_table_info(newinfo);
1119 static int do_add_counters(struct net *net, const void __user *user,
1120 unsigned int len, int compat)
1123 struct xt_counters_info tmp;
1124 struct xt_counters *paddc;
1125 unsigned int num_counters;
1130 const struct xt_table_info *private;
1132 struct arpt_entry *iter;
1133 unsigned int addend;
1134 #ifdef CONFIG_COMPAT
1135 struct compat_xt_counters_info compat_tmp;
1139 size = sizeof(struct compat_xt_counters_info);
1144 size = sizeof(struct xt_counters_info);
1147 if (copy_from_user(ptmp, user, size) != 0)
1150 #ifdef CONFIG_COMPAT
1152 num_counters = compat_tmp.num_counters;
1153 name = compat_tmp.name;
1157 num_counters = tmp.num_counters;
1161 if (len != size + num_counters * sizeof(struct xt_counters))
1164 paddc = vmalloc(len - size);
1168 if (copy_from_user(paddc, user + size, len - size) != 0) {
1173 t = xt_find_table_lock(net, NFPROTO_ARP, name);
1174 if (IS_ERR_OR_NULL(t)) {
1175 ret = t ? PTR_ERR(t) : -ENOENT;
1180 private = t->private;
1181 if (private->number != num_counters) {
1183 goto unlock_up_free;
1188 addend = xt_write_recseq_begin();
1189 xt_entry_foreach(iter, private->entries, private->size) {
1190 struct xt_counters *tmp;
1192 tmp = xt_get_this_cpu_counter(&iter->counters);
1193 ADD_COUNTER(*tmp, paddc[i].bcnt, paddc[i].pcnt);
1196 xt_write_recseq_end(addend);
1207 #ifdef CONFIG_COMPAT
1208 static inline void compat_release_entry(struct compat_arpt_entry *e)
1210 struct xt_entry_target *t;
1212 t = compat_arpt_get_target(e);
1213 module_put(t->u.kernel.target->me);
1217 check_compat_entry_size_and_hooks(struct compat_arpt_entry *e,
1218 struct xt_table_info *newinfo,
1220 const unsigned char *base,
1221 const unsigned char *limit,
1222 const unsigned int *hook_entries,
1223 const unsigned int *underflows,
1226 struct xt_entry_target *t;
1227 struct xt_target *target;
1228 unsigned int entry_offset;
1231 duprintf("check_compat_entry_size_and_hooks %p\n", e);
1232 if ((unsigned long)e % __alignof__(struct compat_arpt_entry) != 0 ||
1233 (unsigned char *)e + sizeof(struct compat_arpt_entry) >= limit) {
1234 duprintf("Bad offset %p, limit = %p\n", e, limit);
1238 if (e->next_offset < sizeof(struct compat_arpt_entry) +
1239 sizeof(struct compat_xt_entry_target)) {
1240 duprintf("checking: element %p size %u\n",
1245 /* For purposes of check_entry casting the compat entry is fine */
1246 ret = check_entry((struct arpt_entry *)e, name);
1250 off = sizeof(struct arpt_entry) - sizeof(struct compat_arpt_entry);
1251 entry_offset = (void *)e - (void *)base;
1253 t = compat_arpt_get_target(e);
1254 target = xt_request_find_target(NFPROTO_ARP, t->u.user.name,
1255 t->u.user.revision);
1256 if (IS_ERR(target)) {
1257 duprintf("check_compat_entry_size_and_hooks: `%s' not found\n",
1259 ret = PTR_ERR(target);
1262 t->u.kernel.target = target;
1264 off += xt_compat_target_offset(target);
1266 ret = xt_compat_add_offset(NFPROTO_ARP, entry_offset, off);
1268 goto release_target;
1270 /* Check hooks & underflows */
1271 for (h = 0; h < NF_ARP_NUMHOOKS; h++) {
1272 if ((unsigned char *)e - base == hook_entries[h])
1273 newinfo->hook_entry[h] = hook_entries[h];
1274 if ((unsigned char *)e - base == underflows[h])
1275 newinfo->underflow[h] = underflows[h];
1278 /* Clear counters and comefrom */
1279 memset(&e->counters, 0, sizeof(e->counters));
1284 module_put(t->u.kernel.target->me);
1290 compat_copy_entry_from_user(struct compat_arpt_entry *e, void **dstptr,
1291 unsigned int *size, const char *name,
1292 struct xt_table_info *newinfo, unsigned char *base)
1294 struct xt_entry_target *t;
1295 struct xt_target *target;
1296 struct arpt_entry *de;
1297 unsigned int origsize;
1302 de = (struct arpt_entry *)*dstptr;
1303 memcpy(de, e, sizeof(struct arpt_entry));
1304 memcpy(&de->counters, &e->counters, sizeof(e->counters));
1306 *dstptr += sizeof(struct arpt_entry);
1307 *size += sizeof(struct arpt_entry) - sizeof(struct compat_arpt_entry);
1309 de->target_offset = e->target_offset - (origsize - *size);
1310 t = compat_arpt_get_target(e);
1311 target = t->u.kernel.target;
1312 xt_compat_target_from_user(t, dstptr, size);
1314 de->next_offset = e->next_offset - (origsize - *size);
1315 for (h = 0; h < NF_ARP_NUMHOOKS; h++) {
1316 if ((unsigned char *)de - base < newinfo->hook_entry[h])
1317 newinfo->hook_entry[h] -= origsize - *size;
1318 if ((unsigned char *)de - base < newinfo->underflow[h])
1319 newinfo->underflow[h] -= origsize - *size;
1324 static int translate_compat_table(const char *name,
1325 unsigned int valid_hooks,
1326 struct xt_table_info **pinfo,
1328 unsigned int total_size,
1329 unsigned int number,
1330 unsigned int *hook_entries,
1331 unsigned int *underflows)
1334 struct xt_table_info *newinfo, *info;
1335 void *pos, *entry0, *entry1;
1336 struct compat_arpt_entry *iter0;
1337 struct arpt_entry *iter1;
1344 info->number = number;
1346 /* Init all hooks to impossible value. */
1347 for (i = 0; i < NF_ARP_NUMHOOKS; i++) {
1348 info->hook_entry[i] = 0xFFFFFFFF;
1349 info->underflow[i] = 0xFFFFFFFF;
1352 duprintf("translate_compat_table: size %u\n", info->size);
1354 xt_compat_lock(NFPROTO_ARP);
1355 xt_compat_init_offsets(NFPROTO_ARP, number);
1356 /* Walk through entries, checking offsets. */
1357 xt_entry_foreach(iter0, entry0, total_size) {
1358 ret = check_compat_entry_size_and_hooks(iter0, info, &size,
1360 entry0 + total_size,
1371 duprintf("translate_compat_table: %u not %u entries\n",
1376 /* Check hooks all assigned */
1377 for (i = 0; i < NF_ARP_NUMHOOKS; i++) {
1378 /* Only hooks which are valid */
1379 if (!(valid_hooks & (1 << i)))
1381 if (info->hook_entry[i] == 0xFFFFFFFF) {
1382 duprintf("Invalid hook entry %u %u\n",
1383 i, hook_entries[i]);
1386 if (info->underflow[i] == 0xFFFFFFFF) {
1387 duprintf("Invalid underflow %u %u\n",
1394 newinfo = xt_alloc_table_info(size);
1398 newinfo->number = number;
1399 for (i = 0; i < NF_ARP_NUMHOOKS; i++) {
1400 newinfo->hook_entry[i] = info->hook_entry[i];
1401 newinfo->underflow[i] = info->underflow[i];
1403 entry1 = newinfo->entries;
1406 xt_entry_foreach(iter0, entry0, total_size) {
1407 ret = compat_copy_entry_from_user(iter0, &pos, &size,
1408 name, newinfo, entry1);
1412 xt_compat_flush_offsets(NFPROTO_ARP);
1413 xt_compat_unlock(NFPROTO_ARP);
1418 if (!mark_source_chains(newinfo, valid_hooks, entry1))
1422 xt_entry_foreach(iter1, entry1, newinfo->size) {
1423 iter1->counters.pcnt = xt_percpu_counter_alloc();
1424 if (IS_ERR_VALUE(iter1->counters.pcnt)) {
1429 ret = check_target(iter1, name);
1431 xt_percpu_counter_free(iter1->counters.pcnt);
1435 if (strcmp(arpt_get_target(iter1)->u.user.name,
1436 XT_ERROR_TARGET) == 0)
1437 ++newinfo->stacksize;
1441 * The first i matches need cleanup_entry (calls ->destroy)
1442 * because they had called ->check already. The other j-i
1443 * entries need only release.
1447 xt_entry_foreach(iter0, entry0, newinfo->size) {
1452 compat_release_entry(iter0);
1454 xt_entry_foreach(iter1, entry1, newinfo->size) {
1457 cleanup_entry(iter1);
1459 xt_free_table_info(newinfo);
1465 xt_free_table_info(info);
1469 xt_free_table_info(newinfo);
1471 xt_entry_foreach(iter0, entry0, total_size) {
1474 compat_release_entry(iter0);
1478 xt_compat_flush_offsets(NFPROTO_ARP);
1479 xt_compat_unlock(NFPROTO_ARP);
1483 struct compat_arpt_replace {
1484 char name[XT_TABLE_MAXNAMELEN];
1488 u32 hook_entry[NF_ARP_NUMHOOKS];
1489 u32 underflow[NF_ARP_NUMHOOKS];
1491 compat_uptr_t counters;
1492 struct compat_arpt_entry entries[0];
1495 static int compat_do_replace(struct net *net, void __user *user,
1499 struct compat_arpt_replace tmp;
1500 struct xt_table_info *newinfo;
1501 void *loc_cpu_entry;
1502 struct arpt_entry *iter;
1504 if (copy_from_user(&tmp, user, sizeof(tmp)) != 0)
1507 /* overflow check */
1508 if (tmp.size >= INT_MAX / num_possible_cpus())
1510 if (tmp.num_counters >= INT_MAX / sizeof(struct xt_counters))
1512 if (tmp.num_counters == 0)
1515 tmp.name[sizeof(tmp.name)-1] = 0;
1517 newinfo = xt_alloc_table_info(tmp.size);
1521 loc_cpu_entry = newinfo->entries;
1522 if (copy_from_user(loc_cpu_entry, user + sizeof(tmp), tmp.size) != 0) {
1527 ret = translate_compat_table(tmp.name, tmp.valid_hooks,
1528 &newinfo, &loc_cpu_entry, tmp.size,
1529 tmp.num_entries, tmp.hook_entry,
1534 duprintf("compat_do_replace: Translated table\n");
1536 ret = __do_replace(net, tmp.name, tmp.valid_hooks, newinfo,
1537 tmp.num_counters, compat_ptr(tmp.counters));
1539 goto free_newinfo_untrans;
1542 free_newinfo_untrans:
1543 xt_entry_foreach(iter, loc_cpu_entry, newinfo->size)
1544 cleanup_entry(iter);
1546 xt_free_table_info(newinfo);
1550 static int compat_do_arpt_set_ctl(struct sock *sk, int cmd, void __user *user,
1555 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
1559 case ARPT_SO_SET_REPLACE:
1560 ret = compat_do_replace(sock_net(sk), user, len);
1563 case ARPT_SO_SET_ADD_COUNTERS:
1564 ret = do_add_counters(sock_net(sk), user, len, 1);
1568 duprintf("do_arpt_set_ctl: unknown request %i\n", cmd);
1575 static int compat_copy_entry_to_user(struct arpt_entry *e, void __user **dstptr,
1576 compat_uint_t *size,
1577 struct xt_counters *counters,
1580 struct xt_entry_target *t;
1581 struct compat_arpt_entry __user *ce;
1582 u_int16_t target_offset, next_offset;
1583 compat_uint_t origsize;
1587 ce = (struct compat_arpt_entry __user *)*dstptr;
1588 if (copy_to_user(ce, e, sizeof(struct arpt_entry)) != 0 ||
1589 copy_to_user(&ce->counters, &counters[i],
1590 sizeof(counters[i])) != 0)
1593 *dstptr += sizeof(struct compat_arpt_entry);
1594 *size -= sizeof(struct arpt_entry) - sizeof(struct compat_arpt_entry);
1596 target_offset = e->target_offset - (origsize - *size);
1598 t = arpt_get_target(e);
1599 ret = xt_compat_target_to_user(t, dstptr, size);
1602 next_offset = e->next_offset - (origsize - *size);
1603 if (put_user(target_offset, &ce->target_offset) != 0 ||
1604 put_user(next_offset, &ce->next_offset) != 0)
1609 static int compat_copy_entries_to_user(unsigned int total_size,
1610 struct xt_table *table,
1611 void __user *userptr)
1613 struct xt_counters *counters;
1614 const struct xt_table_info *private = table->private;
1619 struct arpt_entry *iter;
1621 counters = alloc_counters(table);
1622 if (IS_ERR(counters))
1623 return PTR_ERR(counters);
1627 xt_entry_foreach(iter, private->entries, total_size) {
1628 ret = compat_copy_entry_to_user(iter, &pos,
1629 &size, counters, i++);
1637 struct compat_arpt_get_entries {
1638 char name[XT_TABLE_MAXNAMELEN];
1640 struct compat_arpt_entry entrytable[0];
1643 static int compat_get_entries(struct net *net,
1644 struct compat_arpt_get_entries __user *uptr,
1648 struct compat_arpt_get_entries get;
1651 if (*len < sizeof(get)) {
1652 duprintf("compat_get_entries: %u < %zu\n", *len, sizeof(get));
1655 if (copy_from_user(&get, uptr, sizeof(get)) != 0)
1657 if (*len != sizeof(struct compat_arpt_get_entries) + get.size) {
1658 duprintf("compat_get_entries: %u != %zu\n",
1659 *len, sizeof(get) + get.size);
1663 xt_compat_lock(NFPROTO_ARP);
1664 t = xt_find_table_lock(net, NFPROTO_ARP, get.name);
1665 if (!IS_ERR_OR_NULL(t)) {
1666 const struct xt_table_info *private = t->private;
1667 struct xt_table_info info;
1669 duprintf("t->private->number = %u\n", private->number);
1670 ret = compat_table_info(private, &info);
1671 if (!ret && get.size == info.size) {
1672 ret = compat_copy_entries_to_user(private->size,
1673 t, uptr->entrytable);
1675 duprintf("compat_get_entries: I've got %u not %u!\n",
1676 private->size, get.size);
1679 xt_compat_flush_offsets(NFPROTO_ARP);
1683 ret = t ? PTR_ERR(t) : -ENOENT;
1685 xt_compat_unlock(NFPROTO_ARP);
1689 static int do_arpt_get_ctl(struct sock *, int, void __user *, int *);
1691 static int compat_do_arpt_get_ctl(struct sock *sk, int cmd, void __user *user,
1696 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
1700 case ARPT_SO_GET_INFO:
1701 ret = get_info(sock_net(sk), user, len, 1);
1703 case ARPT_SO_GET_ENTRIES:
1704 ret = compat_get_entries(sock_net(sk), user, len);
1707 ret = do_arpt_get_ctl(sk, cmd, user, len);
1713 static int do_arpt_set_ctl(struct sock *sk, int cmd, void __user *user, unsigned int len)
1717 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
1721 case ARPT_SO_SET_REPLACE:
1722 ret = do_replace(sock_net(sk), user, len);
1725 case ARPT_SO_SET_ADD_COUNTERS:
1726 ret = do_add_counters(sock_net(sk), user, len, 0);
1730 duprintf("do_arpt_set_ctl: unknown request %i\n", cmd);
1737 static int do_arpt_get_ctl(struct sock *sk, int cmd, void __user *user, int *len)
1741 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
1745 case ARPT_SO_GET_INFO:
1746 ret = get_info(sock_net(sk), user, len, 0);
1749 case ARPT_SO_GET_ENTRIES:
1750 ret = get_entries(sock_net(sk), user, len);
1753 case ARPT_SO_GET_REVISION_TARGET: {
1754 struct xt_get_revision rev;
1756 if (*len != sizeof(rev)) {
1760 if (copy_from_user(&rev, user, sizeof(rev)) != 0) {
1764 rev.name[sizeof(rev.name)-1] = 0;
1766 try_then_request_module(xt_find_revision(NFPROTO_ARP, rev.name,
1767 rev.revision, 1, &ret),
1768 "arpt_%s", rev.name);
1773 duprintf("do_arpt_get_ctl: unknown request %i\n", cmd);
1780 struct xt_table *arpt_register_table(struct net *net,
1781 const struct xt_table *table,
1782 const struct arpt_replace *repl)
1785 struct xt_table_info *newinfo;
1786 struct xt_table_info bootstrap = {0};
1787 void *loc_cpu_entry;
1788 struct xt_table *new_table;
1790 newinfo = xt_alloc_table_info(repl->size);
1796 loc_cpu_entry = newinfo->entries;
1797 memcpy(loc_cpu_entry, repl->entries, repl->size);
1799 ret = translate_table(newinfo, loc_cpu_entry, repl);
1800 duprintf("arpt_register_table: translate table gives %d\n", ret);
1804 new_table = xt_register_table(net, table, &bootstrap, newinfo);
1805 if (IS_ERR(new_table)) {
1806 ret = PTR_ERR(new_table);
1812 xt_free_table_info(newinfo);
1814 return ERR_PTR(ret);
1817 void arpt_unregister_table(struct xt_table *table)
1819 struct xt_table_info *private;
1820 void *loc_cpu_entry;
1821 struct module *table_owner = table->me;
1822 struct arpt_entry *iter;
1824 private = xt_unregister_table(table);
1826 /* Decrease module usage counts and free resources */
1827 loc_cpu_entry = private->entries;
1828 xt_entry_foreach(iter, loc_cpu_entry, private->size)
1829 cleanup_entry(iter);
1830 if (private->number > private->initial_entries)
1831 module_put(table_owner);
1832 xt_free_table_info(private);
1835 /* The built-in targets: standard (NULL) and error. */
1836 static struct xt_target arpt_builtin_tg[] __read_mostly = {
1838 .name = XT_STANDARD_TARGET,
1839 .targetsize = sizeof(int),
1840 .family = NFPROTO_ARP,
1841 #ifdef CONFIG_COMPAT
1842 .compatsize = sizeof(compat_int_t),
1843 .compat_from_user = compat_standard_from_user,
1844 .compat_to_user = compat_standard_to_user,
1848 .name = XT_ERROR_TARGET,
1849 .target = arpt_error,
1850 .targetsize = XT_FUNCTION_MAXNAMELEN,
1851 .family = NFPROTO_ARP,
1855 static struct nf_sockopt_ops arpt_sockopts = {
1857 .set_optmin = ARPT_BASE_CTL,
1858 .set_optmax = ARPT_SO_SET_MAX+1,
1859 .set = do_arpt_set_ctl,
1860 #ifdef CONFIG_COMPAT
1861 .compat_set = compat_do_arpt_set_ctl,
1863 .get_optmin = ARPT_BASE_CTL,
1864 .get_optmax = ARPT_SO_GET_MAX+1,
1865 .get = do_arpt_get_ctl,
1866 #ifdef CONFIG_COMPAT
1867 .compat_get = compat_do_arpt_get_ctl,
1869 .owner = THIS_MODULE,
1872 static int __net_init arp_tables_net_init(struct net *net)
1874 return xt_proto_init(net, NFPROTO_ARP);
1877 static void __net_exit arp_tables_net_exit(struct net *net)
1879 xt_proto_fini(net, NFPROTO_ARP);
1882 static struct pernet_operations arp_tables_net_ops = {
1883 .init = arp_tables_net_init,
1884 .exit = arp_tables_net_exit,
1887 static int __init arp_tables_init(void)
1891 ret = register_pernet_subsys(&arp_tables_net_ops);
1895 /* No one else will be downing sem now, so we won't sleep */
1896 ret = xt_register_targets(arpt_builtin_tg, ARRAY_SIZE(arpt_builtin_tg));
1900 /* Register setsockopt */
1901 ret = nf_register_sockopt(&arpt_sockopts);
1905 printk(KERN_INFO "arp_tables: (C) 2002 David S. Miller\n");
1909 xt_unregister_targets(arpt_builtin_tg, ARRAY_SIZE(arpt_builtin_tg));
1911 unregister_pernet_subsys(&arp_tables_net_ops);
1916 static void __exit arp_tables_fini(void)
1918 nf_unregister_sockopt(&arpt_sockopts);
1919 xt_unregister_targets(arpt_builtin_tg, ARRAY_SIZE(arpt_builtin_tg));
1920 unregister_pernet_subsys(&arp_tables_net_ops);
1923 EXPORT_SYMBOL(arpt_register_table);
1924 EXPORT_SYMBOL(arpt_unregister_table);
1925 EXPORT_SYMBOL(arpt_do_table);
1927 module_init(arp_tables_init);
1928 module_exit(arp_tables_fini);