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)
12 #include <linux/kernel.h>
13 #include <linux/skbuff.h>
14 #include <linux/netdevice.h>
15 #include <linux/capability.h>
16 #include <linux/if_arp.h>
17 #include <linux/kmod.h>
18 #include <linux/vmalloc.h>
19 #include <linux/proc_fs.h>
20 #include <linux/module.h>
21 #include <linux/init.h>
23 #include <asm/uaccess.h>
24 #include <linux/mutex.h>
26 #include <linux/netfilter/x_tables.h>
27 #include <linux/netfilter_arp/arp_tables.h>
29 MODULE_LICENSE("GPL");
30 MODULE_AUTHOR("David S. Miller <davem@redhat.com>");
31 MODULE_DESCRIPTION("arptables core");
33 /*#define DEBUG_ARP_TABLES*/
34 /*#define DEBUG_ARP_TABLES_USER*/
36 #ifdef DEBUG_ARP_TABLES
37 #define dprintf(format, args...) printk(format , ## args)
39 #define dprintf(format, args...)
42 #ifdef DEBUG_ARP_TABLES_USER
43 #define duprintf(format, args...) printk(format , ## args)
45 #define duprintf(format, args...)
48 #ifdef CONFIG_NETFILTER_DEBUG
49 #define ARP_NF_ASSERT(x) \
52 printk("ARP_NF_ASSERT: %s:%s:%u\n", \
53 __FUNCTION__, __FILE__, __LINE__); \
56 #define ARP_NF_ASSERT(x)
59 static inline int arp_devaddr_compare(const struct arpt_devaddr_info *ap,
60 char *hdr_addr, int len)
64 if (len > ARPT_DEV_ADDR_LEN_MAX)
65 len = ARPT_DEV_ADDR_LEN_MAX;
68 for (i = 0; i < len; i++)
69 ret |= (hdr_addr[i] ^ ap->addr[i]) & ap->mask[i];
74 /* Returns whether packet matches rule or not. */
75 static inline int arp_packet_match(const struct arphdr *arphdr,
76 struct net_device *dev,
79 const struct arpt_arp *arpinfo)
81 char *arpptr = (char *)(arphdr + 1);
82 char *src_devaddr, *tgt_devaddr;
83 __be32 src_ipaddr, tgt_ipaddr;
86 #define FWINV(bool,invflg) ((bool) ^ !!(arpinfo->invflags & invflg))
88 if (FWINV((arphdr->ar_op & arpinfo->arpop_mask) != arpinfo->arpop,
90 dprintf("ARP operation field mismatch.\n");
91 dprintf("ar_op: %04x info->arpop: %04x info->arpop_mask: %04x\n",
92 arphdr->ar_op, arpinfo->arpop, arpinfo->arpop_mask);
96 if (FWINV((arphdr->ar_hrd & arpinfo->arhrd_mask) != arpinfo->arhrd,
98 dprintf("ARP hardware address format mismatch.\n");
99 dprintf("ar_hrd: %04x info->arhrd: %04x info->arhrd_mask: %04x\n",
100 arphdr->ar_hrd, arpinfo->arhrd, arpinfo->arhrd_mask);
104 if (FWINV((arphdr->ar_pro & arpinfo->arpro_mask) != arpinfo->arpro,
106 dprintf("ARP protocol address format mismatch.\n");
107 dprintf("ar_pro: %04x info->arpro: %04x info->arpro_mask: %04x\n",
108 arphdr->ar_pro, arpinfo->arpro, arpinfo->arpro_mask);
112 if (FWINV((arphdr->ar_hln & arpinfo->arhln_mask) != arpinfo->arhln,
114 dprintf("ARP hardware address length mismatch.\n");
115 dprintf("ar_hln: %02x info->arhln: %02x info->arhln_mask: %02x\n",
116 arphdr->ar_hln, arpinfo->arhln, arpinfo->arhln_mask);
120 src_devaddr = arpptr;
121 arpptr += dev->addr_len;
122 memcpy(&src_ipaddr, arpptr, sizeof(u32));
123 arpptr += sizeof(u32);
124 tgt_devaddr = arpptr;
125 arpptr += dev->addr_len;
126 memcpy(&tgt_ipaddr, arpptr, sizeof(u32));
128 if (FWINV(arp_devaddr_compare(&arpinfo->src_devaddr, src_devaddr, dev->addr_len),
129 ARPT_INV_SRCDEVADDR) ||
130 FWINV(arp_devaddr_compare(&arpinfo->tgt_devaddr, tgt_devaddr, dev->addr_len),
131 ARPT_INV_TGTDEVADDR)) {
132 dprintf("Source or target device address mismatch.\n");
137 if (FWINV((src_ipaddr & arpinfo->smsk.s_addr) != arpinfo->src.s_addr,
139 FWINV(((tgt_ipaddr & arpinfo->tmsk.s_addr) != arpinfo->tgt.s_addr),
141 dprintf("Source or target IP address mismatch.\n");
143 dprintf("SRC: %u.%u.%u.%u. Mask: %u.%u.%u.%u. Target: %u.%u.%u.%u.%s\n",
145 NIPQUAD(arpinfo->smsk.s_addr),
146 NIPQUAD(arpinfo->src.s_addr),
147 arpinfo->invflags & ARPT_INV_SRCIP ? " (INV)" : "");
148 dprintf("TGT: %u.%u.%u.%u Mask: %u.%u.%u.%u Target: %u.%u.%u.%u.%s\n",
150 NIPQUAD(arpinfo->tmsk.s_addr),
151 NIPQUAD(arpinfo->tgt.s_addr),
152 arpinfo->invflags & ARPT_INV_TGTIP ? " (INV)" : "");
156 /* Look for ifname matches. */
157 for (i = 0, ret = 0; i < IFNAMSIZ; i++) {
158 ret |= (indev[i] ^ arpinfo->iniface[i])
159 & arpinfo->iniface_mask[i];
162 if (FWINV(ret != 0, ARPT_INV_VIA_IN)) {
163 dprintf("VIA in mismatch (%s vs %s).%s\n",
164 indev, arpinfo->iniface,
165 arpinfo->invflags&ARPT_INV_VIA_IN ?" (INV)":"");
169 for (i = 0, ret = 0; i < IFNAMSIZ; i++) {
170 ret |= (outdev[i] ^ arpinfo->outiface[i])
171 & arpinfo->outiface_mask[i];
174 if (FWINV(ret != 0, ARPT_INV_VIA_OUT)) {
175 dprintf("VIA out mismatch (%s vs %s).%s\n",
176 outdev, arpinfo->outiface,
177 arpinfo->invflags&ARPT_INV_VIA_OUT ?" (INV)":"");
184 static inline int arp_checkentry(const struct arpt_arp *arp)
186 if (arp->flags & ~ARPT_F_MASK) {
187 duprintf("Unknown flag bits set: %08X\n",
188 arp->flags & ~ARPT_F_MASK);
191 if (arp->invflags & ~ARPT_INV_MASK) {
192 duprintf("Unknown invflag bits set: %08X\n",
193 arp->invflags & ~ARPT_INV_MASK);
200 static unsigned int arpt_error(struct sk_buff *skb,
201 const struct net_device *in,
202 const struct net_device *out,
203 unsigned int hooknum,
204 const struct xt_target *target,
205 const void *targinfo)
208 printk("arp_tables: error: '%s'\n", (char *)targinfo);
213 static inline struct arpt_entry *get_entry(void *base, unsigned int offset)
215 return (struct arpt_entry *)(base + offset);
218 unsigned int arpt_do_table(struct sk_buff *skb,
220 const struct net_device *in,
221 const struct net_device *out,
222 struct arpt_table *table)
224 static const char nulldevname[IFNAMSIZ];
225 unsigned int verdict = NF_DROP;
227 bool hotdrop = false;
228 struct arpt_entry *e, *back;
229 const char *indev, *outdev;
231 struct xt_table_info *private;
233 /* ARP header, plus 2 device addresses, plus 2 IP addresses. */
234 if (!pskb_may_pull(skb, (sizeof(struct arphdr) +
235 (2 * skb->dev->addr_len) +
239 indev = in ? in->name : nulldevname;
240 outdev = out ? out->name : nulldevname;
242 read_lock_bh(&table->lock);
243 private = table->private;
244 table_base = (void *)private->entries[smp_processor_id()];
245 e = get_entry(table_base, private->hook_entry[hook]);
246 back = get_entry(table_base, private->underflow[hook]);
250 if (arp_packet_match(arp, skb->dev, indev, outdev, &e->arp)) {
251 struct arpt_entry_target *t;
254 hdr_len = sizeof(*arp) + (2 * sizeof(struct in_addr)) +
255 (2 * skb->dev->addr_len);
256 ADD_COUNTER(e->counters, hdr_len, 1);
258 t = arpt_get_target(e);
260 /* Standard target? */
261 if (!t->u.kernel.target->target) {
264 v = ((struct arpt_standard_target *)t)->verdict;
266 /* Pop from stack? */
267 if (v != ARPT_RETURN) {
268 verdict = (unsigned)(-v) - 1;
272 back = get_entry(table_base,
277 != (void *)e + e->next_offset) {
278 /* Save old back ptr in next entry */
279 struct arpt_entry *next
280 = (void *)e + e->next_offset;
282 (void *)back - table_base;
284 /* set back pointer to next entry */
288 e = get_entry(table_base, v);
290 /* Targets which reenter must return
293 verdict = t->u.kernel.target->target(skb,
299 /* Target might have changed stuff. */
302 if (verdict == ARPT_CONTINUE)
303 e = (void *)e + e->next_offset;
309 e = (void *)e + e->next_offset;
312 read_unlock_bh(&table->lock);
320 /* All zeroes == unconditional rule. */
321 static inline int unconditional(const struct arpt_arp *arp)
325 for (i = 0; i < sizeof(*arp)/sizeof(__u32); i++)
326 if (((__u32 *)arp)[i])
332 /* Figures out from what hook each rule can be called: returns 0 if
333 * there are loops. Puts hook bitmask in comefrom.
335 static int mark_source_chains(struct xt_table_info *newinfo,
336 unsigned int valid_hooks, void *entry0)
340 /* No recursion; use packet counter to save back ptrs (reset
341 * to 0 as we leave), and comefrom to save source hook bitmask.
343 for (hook = 0; hook < NF_ARP_NUMHOOKS; hook++) {
344 unsigned int pos = newinfo->hook_entry[hook];
346 = (struct arpt_entry *)(entry0 + pos);
348 if (!(valid_hooks & (1 << hook)))
351 /* Set initial back pointer. */
352 e->counters.pcnt = pos;
355 struct arpt_standard_target *t
356 = (void *)arpt_get_target(e);
357 int visited = e->comefrom & (1 << hook);
359 if (e->comefrom & (1 << NF_ARP_NUMHOOKS)) {
360 printk("arptables: loop hook %u pos %u %08X.\n",
361 hook, pos, e->comefrom);
365 |= ((1 << hook) | (1 << NF_ARP_NUMHOOKS));
367 /* Unconditional return/END. */
368 if ((e->target_offset == sizeof(struct arpt_entry)
369 && (strcmp(t->target.u.user.name,
370 ARPT_STANDARD_TARGET) == 0)
372 && unconditional(&e->arp)) || visited) {
373 unsigned int oldpos, size;
375 if (t->verdict < -NF_MAX_VERDICT - 1) {
376 duprintf("mark_source_chains: bad "
377 "negative verdict (%i)\n",
382 /* Return: backtrack through the last
386 e->comefrom ^= (1<<NF_ARP_NUMHOOKS);
388 pos = e->counters.pcnt;
389 e->counters.pcnt = 0;
391 /* We're at the start. */
395 e = (struct arpt_entry *)
397 } while (oldpos == pos + e->next_offset);
400 size = e->next_offset;
401 e = (struct arpt_entry *)
402 (entry0 + pos + size);
403 e->counters.pcnt = pos;
406 int newpos = t->verdict;
408 if (strcmp(t->target.u.user.name,
409 ARPT_STANDARD_TARGET) == 0
411 if (newpos > newinfo->size -
412 sizeof(struct arpt_entry)) {
413 duprintf("mark_source_chains: "
414 "bad verdict (%i)\n",
419 /* This a jump; chase it. */
420 duprintf("Jump rule %u -> %u\n",
423 /* ... this is a fallthru */
424 newpos = pos + e->next_offset;
426 e = (struct arpt_entry *)
428 e->counters.pcnt = pos;
433 duprintf("Finished chain %u\n", hook);
438 static inline int check_entry(struct arpt_entry *e, const char *name, unsigned int size,
441 struct arpt_entry_target *t;
442 struct arpt_target *target;
445 if (!arp_checkentry(&e->arp)) {
446 duprintf("arp_tables: arp check failed %p %s.\n", e, name);
450 if (e->target_offset + sizeof(struct arpt_entry_target) > e->next_offset)
453 t = arpt_get_target(e);
454 if (e->target_offset + t->u.target_size > e->next_offset)
457 target = try_then_request_module(xt_find_target(NF_ARP, t->u.user.name,
459 "arpt_%s", t->u.user.name);
460 if (IS_ERR(target) || !target) {
461 duprintf("check_entry: `%s' not found\n", t->u.user.name);
462 ret = target ? PTR_ERR(target) : -ENOENT;
465 t->u.kernel.target = target;
467 ret = xt_check_target(target, NF_ARP, t->u.target_size - sizeof(*t),
468 name, e->comefrom, 0, 0);
472 if (t->u.kernel.target->checkentry
473 && !t->u.kernel.target->checkentry(name, e, target, t->data,
475 duprintf("arp_tables: check failed for `%s'.\n",
476 t->u.kernel.target->name);
484 module_put(t->u.kernel.target->me);
489 static inline int check_entry_size_and_hooks(struct arpt_entry *e,
490 struct xt_table_info *newinfo,
492 unsigned char *limit,
493 const unsigned int *hook_entries,
494 const unsigned int *underflows,
499 if ((unsigned long)e % __alignof__(struct arpt_entry) != 0
500 || (unsigned char *)e + sizeof(struct arpt_entry) >= limit) {
501 duprintf("Bad offset %p\n", e);
506 < sizeof(struct arpt_entry) + sizeof(struct arpt_entry_target)) {
507 duprintf("checking: element %p size %u\n",
512 /* Check hooks & underflows */
513 for (h = 0; h < NF_ARP_NUMHOOKS; h++) {
514 if ((unsigned char *)e - base == hook_entries[h])
515 newinfo->hook_entry[h] = hook_entries[h];
516 if ((unsigned char *)e - base == underflows[h])
517 newinfo->underflow[h] = underflows[h];
520 /* FIXME: underflows must be unconditional, standard verdicts
521 < 0 (not ARPT_RETURN). --RR */
523 /* Clear counters and comefrom */
524 e->counters = ((struct xt_counters) { 0, 0 });
531 static inline int cleanup_entry(struct arpt_entry *e, unsigned int *i)
533 struct arpt_entry_target *t;
535 if (i && (*i)-- == 0)
538 t = arpt_get_target(e);
539 if (t->u.kernel.target->destroy)
540 t->u.kernel.target->destroy(t->u.kernel.target, t->data);
541 module_put(t->u.kernel.target->me);
545 /* Checks and translates the user-supplied table segment (held in
548 static int translate_table(const char *name,
549 unsigned int valid_hooks,
550 struct xt_table_info *newinfo,
554 const unsigned int *hook_entries,
555 const unsigned int *underflows)
560 newinfo->size = size;
561 newinfo->number = number;
563 /* Init all hooks to impossible value. */
564 for (i = 0; i < NF_ARP_NUMHOOKS; i++) {
565 newinfo->hook_entry[i] = 0xFFFFFFFF;
566 newinfo->underflow[i] = 0xFFFFFFFF;
569 duprintf("translate_table: size %u\n", newinfo->size);
572 /* Walk through entries, checking offsets. */
573 ret = ARPT_ENTRY_ITERATE(entry0, newinfo->size,
574 check_entry_size_and_hooks,
578 hook_entries, underflows, &i);
579 duprintf("translate_table: ARPT_ENTRY_ITERATE gives %d\n", ret);
584 duprintf("translate_table: %u not %u entries\n",
589 /* Check hooks all assigned */
590 for (i = 0; i < NF_ARP_NUMHOOKS; i++) {
591 /* Only hooks which are valid */
592 if (!(valid_hooks & (1 << i)))
594 if (newinfo->hook_entry[i] == 0xFFFFFFFF) {
595 duprintf("Invalid hook entry %u %u\n",
599 if (newinfo->underflow[i] == 0xFFFFFFFF) {
600 duprintf("Invalid underflow %u %u\n",
606 if (!mark_source_chains(newinfo, valid_hooks, entry0)) {
607 duprintf("Looping hook\n");
611 /* Finally, each sanity check must pass */
613 ret = ARPT_ENTRY_ITERATE(entry0, newinfo->size,
614 check_entry, name, size, &i);
617 ARPT_ENTRY_ITERATE(entry0, newinfo->size,
622 /* And one copy for every other CPU */
623 for_each_possible_cpu(i) {
624 if (newinfo->entries[i] && newinfo->entries[i] != entry0)
625 memcpy(newinfo->entries[i], entry0, newinfo->size);
632 static inline int add_entry_to_counter(const struct arpt_entry *e,
633 struct xt_counters total[],
636 ADD_COUNTER(total[*i], e->counters.bcnt, e->counters.pcnt);
642 static inline int set_entry_to_counter(const struct arpt_entry *e,
643 struct xt_counters total[],
646 SET_COUNTER(total[*i], e->counters.bcnt, e->counters.pcnt);
652 static void get_counters(const struct xt_table_info *t,
653 struct xt_counters counters[])
659 /* Instead of clearing (by a previous call to memset())
660 * the counters and using adds, we set the counters
661 * with data used by 'current' CPU
662 * We dont care about preemption here.
664 curcpu = raw_smp_processor_id();
667 ARPT_ENTRY_ITERATE(t->entries[curcpu],
669 set_entry_to_counter,
673 for_each_possible_cpu(cpu) {
677 ARPT_ENTRY_ITERATE(t->entries[cpu],
679 add_entry_to_counter,
685 static int copy_entries_to_user(unsigned int total_size,
686 struct arpt_table *table,
687 void __user *userptr)
689 unsigned int off, num, countersize;
690 struct arpt_entry *e;
691 struct xt_counters *counters;
692 struct xt_table_info *private = table->private;
696 /* We need atomic snapshot of counters: rest doesn't change
697 * (other than comefrom, which userspace doesn't care
700 countersize = sizeof(struct xt_counters) * private->number;
701 counters = vmalloc_node(countersize, numa_node_id());
703 if (counters == NULL)
706 /* First, sum counters... */
707 write_lock_bh(&table->lock);
708 get_counters(private, counters);
709 write_unlock_bh(&table->lock);
711 loc_cpu_entry = private->entries[raw_smp_processor_id()];
712 /* ... then copy entire thing ... */
713 if (copy_to_user(userptr, loc_cpu_entry, total_size) != 0) {
718 /* FIXME: use iterator macros --RR */
719 /* ... then go back and fix counters and names */
720 for (off = 0, num = 0; off < total_size; off += e->next_offset, num++){
721 struct arpt_entry_target *t;
723 e = (struct arpt_entry *)(loc_cpu_entry + off);
724 if (copy_to_user(userptr + off
725 + offsetof(struct arpt_entry, counters),
727 sizeof(counters[num])) != 0) {
732 t = arpt_get_target(e);
733 if (copy_to_user(userptr + off + e->target_offset
734 + offsetof(struct arpt_entry_target,
736 t->u.kernel.target->name,
737 strlen(t->u.kernel.target->name)+1) != 0) {
748 static int get_entries(const struct arpt_get_entries *entries,
749 struct arpt_get_entries __user *uptr)
752 struct arpt_table *t;
754 t = xt_find_table_lock(NF_ARP, entries->name);
755 if (t && !IS_ERR(t)) {
756 struct xt_table_info *private = t->private;
757 duprintf("t->private->number = %u\n",
759 if (entries->size == private->size)
760 ret = copy_entries_to_user(private->size,
761 t, uptr->entrytable);
763 duprintf("get_entries: I've got %u not %u!\n",
764 private->size, entries->size);
770 ret = t ? PTR_ERR(t) : -ENOENT;
775 static int do_replace(void __user *user, unsigned int len)
778 struct arpt_replace tmp;
779 struct arpt_table *t;
780 struct xt_table_info *newinfo, *oldinfo;
781 struct xt_counters *counters;
782 void *loc_cpu_entry, *loc_cpu_old_entry;
784 if (copy_from_user(&tmp, user, sizeof(tmp)) != 0)
787 /* Hack: Causes ipchains to give correct error msg --RR */
788 if (len != sizeof(tmp) + tmp.size)
792 if (tmp.num_counters >= INT_MAX / sizeof(struct xt_counters))
795 newinfo = xt_alloc_table_info(tmp.size);
799 /* choose the copy that is on our node/cpu */
800 loc_cpu_entry = newinfo->entries[raw_smp_processor_id()];
801 if (copy_from_user(loc_cpu_entry, user + sizeof(tmp),
807 counters = vmalloc(tmp.num_counters * sizeof(struct xt_counters));
813 ret = translate_table(tmp.name, tmp.valid_hooks,
814 newinfo, loc_cpu_entry, tmp.size, tmp.num_entries,
815 tmp.hook_entry, tmp.underflow);
817 goto free_newinfo_counters;
819 duprintf("arp_tables: Translated table\n");
821 t = try_then_request_module(xt_find_table_lock(NF_ARP, tmp.name),
822 "arptable_%s", tmp.name);
823 if (!t || IS_ERR(t)) {
824 ret = t ? PTR_ERR(t) : -ENOENT;
825 goto free_newinfo_counters_untrans;
829 if (tmp.valid_hooks != t->valid_hooks) {
830 duprintf("Valid hook crap: %08X vs %08X\n",
831 tmp.valid_hooks, t->valid_hooks);
836 oldinfo = xt_replace_table(t, tmp.num_counters, newinfo, &ret);
840 /* Update module usage count based on number of rules */
841 duprintf("do_replace: oldnum=%u, initnum=%u, newnum=%u\n",
842 oldinfo->number, oldinfo->initial_entries, newinfo->number);
843 if ((oldinfo->number > oldinfo->initial_entries) ||
844 (newinfo->number <= oldinfo->initial_entries))
846 if ((oldinfo->number > oldinfo->initial_entries) &&
847 (newinfo->number <= oldinfo->initial_entries))
850 /* Get the old counters. */
851 get_counters(oldinfo, counters);
852 /* Decrease module usage counts and free resource */
853 loc_cpu_old_entry = oldinfo->entries[raw_smp_processor_id()];
854 ARPT_ENTRY_ITERATE(loc_cpu_old_entry, oldinfo->size, cleanup_entry,NULL);
856 xt_free_table_info(oldinfo);
857 if (copy_to_user(tmp.counters, counters,
858 sizeof(struct xt_counters) * tmp.num_counters) != 0)
867 free_newinfo_counters_untrans:
868 ARPT_ENTRY_ITERATE(loc_cpu_entry, newinfo->size, cleanup_entry, NULL);
869 free_newinfo_counters:
872 xt_free_table_info(newinfo);
876 /* We're lazy, and add to the first CPU; overflow works its fey magic
877 * and everything is OK.
879 static inline int add_counter_to_entry(struct arpt_entry *e,
880 const struct xt_counters addme[],
884 ADD_COUNTER(e->counters, addme[*i].bcnt, addme[*i].pcnt);
890 static int do_add_counters(void __user *user, unsigned int len)
893 struct xt_counters_info tmp, *paddc;
894 struct arpt_table *t;
895 struct xt_table_info *private;
899 if (copy_from_user(&tmp, user, sizeof(tmp)) != 0)
902 if (len != sizeof(tmp) + tmp.num_counters*sizeof(struct xt_counters))
905 paddc = vmalloc(len);
909 if (copy_from_user(paddc, user, len) != 0) {
914 t = xt_find_table_lock(NF_ARP, tmp.name);
915 if (!t || IS_ERR(t)) {
916 ret = t ? PTR_ERR(t) : -ENOENT;
920 write_lock_bh(&t->lock);
921 private = t->private;
922 if (private->number != tmp.num_counters) {
928 /* Choose the copy that is on our node */
929 loc_cpu_entry = private->entries[smp_processor_id()];
930 ARPT_ENTRY_ITERATE(loc_cpu_entry,
932 add_counter_to_entry,
936 write_unlock_bh(&t->lock);
945 static int do_arpt_set_ctl(struct sock *sk, int cmd, void __user *user, unsigned int len)
949 if (!capable(CAP_NET_ADMIN))
953 case ARPT_SO_SET_REPLACE:
954 ret = do_replace(user, len);
957 case ARPT_SO_SET_ADD_COUNTERS:
958 ret = do_add_counters(user, len);
962 duprintf("do_arpt_set_ctl: unknown request %i\n", cmd);
969 static int do_arpt_get_ctl(struct sock *sk, int cmd, void __user *user, int *len)
973 if (!capable(CAP_NET_ADMIN))
977 case ARPT_SO_GET_INFO: {
978 char name[ARPT_TABLE_MAXNAMELEN];
979 struct arpt_table *t;
981 if (*len != sizeof(struct arpt_getinfo)) {
982 duprintf("length %u != %Zu\n", *len,
983 sizeof(struct arpt_getinfo));
988 if (copy_from_user(name, user, sizeof(name)) != 0) {
992 name[ARPT_TABLE_MAXNAMELEN-1] = '\0';
994 t = try_then_request_module(xt_find_table_lock(NF_ARP, name),
995 "arptable_%s", name);
996 if (t && !IS_ERR(t)) {
997 struct arpt_getinfo info;
998 struct xt_table_info *private = t->private;
1000 info.valid_hooks = t->valid_hooks;
1001 memcpy(info.hook_entry, private->hook_entry,
1002 sizeof(info.hook_entry));
1003 memcpy(info.underflow, private->underflow,
1004 sizeof(info.underflow));
1005 info.num_entries = private->number;
1006 info.size = private->size;
1007 strcpy(info.name, name);
1009 if (copy_to_user(user, &info, *len) != 0)
1016 ret = t ? PTR_ERR(t) : -ENOENT;
1020 case ARPT_SO_GET_ENTRIES: {
1021 struct arpt_get_entries get;
1023 if (*len < sizeof(get)) {
1024 duprintf("get_entries: %u < %Zu\n", *len, sizeof(get));
1026 } else if (copy_from_user(&get, user, sizeof(get)) != 0) {
1028 } else if (*len != sizeof(struct arpt_get_entries) + get.size) {
1029 duprintf("get_entries: %u != %Zu\n", *len,
1030 sizeof(struct arpt_get_entries) + get.size);
1033 ret = get_entries(&get, user);
1037 case ARPT_SO_GET_REVISION_TARGET: {
1038 struct xt_get_revision rev;
1040 if (*len != sizeof(rev)) {
1044 if (copy_from_user(&rev, user, sizeof(rev)) != 0) {
1049 try_then_request_module(xt_find_revision(NF_ARP, rev.name,
1050 rev.revision, 1, &ret),
1051 "arpt_%s", rev.name);
1056 duprintf("do_arpt_get_ctl: unknown request %i\n", cmd);
1063 int arpt_register_table(struct arpt_table *table,
1064 const struct arpt_replace *repl)
1067 struct xt_table_info *newinfo;
1068 struct xt_table_info bootstrap
1069 = { 0, 0, 0, { 0 }, { 0 }, { } };
1070 void *loc_cpu_entry;
1072 newinfo = xt_alloc_table_info(repl->size);
1078 /* choose the copy on our node/cpu */
1079 loc_cpu_entry = newinfo->entries[raw_smp_processor_id()];
1080 memcpy(loc_cpu_entry, repl->entries, repl->size);
1082 ret = translate_table(table->name, table->valid_hooks,
1083 newinfo, loc_cpu_entry, repl->size,
1088 duprintf("arpt_register_table: translate table gives %d\n", ret);
1090 xt_free_table_info(newinfo);
1094 ret = xt_register_table(table, &bootstrap, newinfo);
1096 xt_free_table_info(newinfo);
1103 void arpt_unregister_table(struct arpt_table *table)
1105 struct xt_table_info *private;
1106 void *loc_cpu_entry;
1108 private = xt_unregister_table(table);
1110 /* Decrease module usage counts and free resources */
1111 loc_cpu_entry = private->entries[raw_smp_processor_id()];
1112 ARPT_ENTRY_ITERATE(loc_cpu_entry, private->size,
1113 cleanup_entry, NULL);
1114 xt_free_table_info(private);
1117 /* The built-in targets: standard (NULL) and error. */
1118 static struct arpt_target arpt_standard_target __read_mostly = {
1119 .name = ARPT_STANDARD_TARGET,
1120 .targetsize = sizeof(int),
1124 static struct arpt_target arpt_error_target __read_mostly = {
1125 .name = ARPT_ERROR_TARGET,
1126 .target = arpt_error,
1127 .targetsize = ARPT_FUNCTION_MAXNAMELEN,
1131 static struct nf_sockopt_ops arpt_sockopts = {
1133 .set_optmin = ARPT_BASE_CTL,
1134 .set_optmax = ARPT_SO_SET_MAX+1,
1135 .set = do_arpt_set_ctl,
1136 .get_optmin = ARPT_BASE_CTL,
1137 .get_optmax = ARPT_SO_GET_MAX+1,
1138 .get = do_arpt_get_ctl,
1139 .owner = THIS_MODULE,
1142 static int __init arp_tables_init(void)
1146 ret = xt_proto_init(NF_ARP);
1150 /* Noone else will be downing sem now, so we won't sleep */
1151 ret = xt_register_target(&arpt_standard_target);
1154 ret = xt_register_target(&arpt_error_target);
1158 /* Register setsockopt */
1159 ret = nf_register_sockopt(&arpt_sockopts);
1163 printk(KERN_INFO "arp_tables: (C) 2002 David S. Miller\n");
1167 xt_unregister_target(&arpt_error_target);
1169 xt_unregister_target(&arpt_standard_target);
1171 xt_proto_fini(NF_ARP);
1176 static void __exit arp_tables_fini(void)
1178 nf_unregister_sockopt(&arpt_sockopts);
1179 xt_unregister_target(&arpt_error_target);
1180 xt_unregister_target(&arpt_standard_target);
1181 xt_proto_fini(NF_ARP);
1184 EXPORT_SYMBOL(arpt_register_table);
1185 EXPORT_SYMBOL(arpt_unregister_table);
1186 EXPORT_SYMBOL(arpt_do_table);
1188 module_init(arp_tables_init);
1189 module_exit(arp_tables_fini);