Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * ebtable_nat |
| 3 | * |
| 4 | * Authors: |
| 5 | * Bart De Schuymer <bdschuym@pandora.be> |
| 6 | * |
| 7 | * April, 2002 |
| 8 | * |
| 9 | */ |
| 10 | |
| 11 | #include <linux/netfilter_bridge/ebtables.h> |
| 12 | #include <linux/module.h> |
| 13 | |
| 14 | #define NAT_VALID_HOOKS ((1 << NF_BR_PRE_ROUTING) | (1 << NF_BR_LOCAL_OUT) | \ |
| 15 | (1 << NF_BR_POST_ROUTING)) |
| 16 | |
| 17 | static struct ebt_entries initial_chains[] = |
| 18 | { |
| 19 | { |
| 20 | .name = "PREROUTING", |
| 21 | .policy = EBT_ACCEPT, |
| 22 | }, |
| 23 | { |
| 24 | .name = "OUTPUT", |
| 25 | .policy = EBT_ACCEPT, |
| 26 | }, |
| 27 | { |
| 28 | .name = "POSTROUTING", |
| 29 | .policy = EBT_ACCEPT, |
| 30 | } |
| 31 | }; |
| 32 | |
Al Viro | 1e419cd | 2006-11-30 19:28:48 -0800 | [diff] [blame] | 33 | static struct ebt_replace_kernel initial_table = |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 34 | { |
| 35 | .name = "nat", |
| 36 | .valid_hooks = NAT_VALID_HOOKS, |
| 37 | .entries_size = 3 * sizeof(struct ebt_entries), |
| 38 | .hook_entry = { |
| 39 | [NF_BR_PRE_ROUTING] = &initial_chains[0], |
| 40 | [NF_BR_LOCAL_OUT] = &initial_chains[1], |
| 41 | [NF_BR_POST_ROUTING] = &initial_chains[2], |
| 42 | }, |
| 43 | .entries = (char *)initial_chains, |
| 44 | }; |
| 45 | |
| 46 | static int check(const struct ebt_table_info *info, unsigned int valid_hooks) |
| 47 | { |
| 48 | if (valid_hooks & ~NAT_VALID_HOOKS) |
| 49 | return -EINVAL; |
| 50 | return 0; |
| 51 | } |
| 52 | |
| 53 | static struct ebt_table frame_nat = |
| 54 | { |
| 55 | .name = "nat", |
| 56 | .table = &initial_table, |
| 57 | .valid_hooks = NAT_VALID_HOOKS, |
Robert P. J. Day | 0718300c | 2008-04-14 09:56:03 +0200 | [diff] [blame] | 58 | .lock = __RW_LOCK_UNLOCKED(frame_nat.lock), |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 59 | .check = check, |
| 60 | .me = THIS_MODULE, |
| 61 | }; |
| 62 | |
| 63 | static unsigned int |
Herbert Xu | 3db05fe | 2007-10-15 00:53:15 -0700 | [diff] [blame] | 64 | ebt_nat_dst(unsigned int hook, struct sk_buff *skb, const struct net_device *in |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 65 | , const struct net_device *out, int (*okfn)(struct sk_buff *)) |
| 66 | { |
Herbert Xu | 3db05fe | 2007-10-15 00:53:15 -0700 | [diff] [blame] | 67 | return ebt_do_table(hook, skb, in, out, &frame_nat); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 68 | } |
| 69 | |
| 70 | static unsigned int |
Herbert Xu | 3db05fe | 2007-10-15 00:53:15 -0700 | [diff] [blame] | 71 | ebt_nat_src(unsigned int hook, struct sk_buff *skb, const struct net_device *in |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 72 | , const struct net_device *out, int (*okfn)(struct sk_buff *)) |
| 73 | { |
Herbert Xu | 3db05fe | 2007-10-15 00:53:15 -0700 | [diff] [blame] | 74 | return ebt_do_table(hook, skb, in, out, &frame_nat); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 75 | } |
| 76 | |
Patrick McHardy | 1999414 | 2007-12-05 01:23:00 -0800 | [diff] [blame] | 77 | static struct nf_hook_ops ebt_ops_nat[] __read_mostly = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 78 | { |
| 79 | .hook = ebt_nat_dst, |
| 80 | .owner = THIS_MODULE, |
| 81 | .pf = PF_BRIDGE, |
| 82 | .hooknum = NF_BR_LOCAL_OUT, |
| 83 | .priority = NF_BR_PRI_NAT_DST_OTHER, |
| 84 | }, |
| 85 | { |
| 86 | .hook = ebt_nat_src, |
| 87 | .owner = THIS_MODULE, |
| 88 | .pf = PF_BRIDGE, |
| 89 | .hooknum = NF_BR_POST_ROUTING, |
| 90 | .priority = NF_BR_PRI_NAT_SRC, |
| 91 | }, |
| 92 | { |
| 93 | .hook = ebt_nat_dst, |
| 94 | .owner = THIS_MODULE, |
| 95 | .pf = PF_BRIDGE, |
| 96 | .hooknum = NF_BR_PRE_ROUTING, |
| 97 | .priority = NF_BR_PRI_NAT_DST_BRIDGED, |
| 98 | }, |
| 99 | }; |
| 100 | |
Andrew Morton | 65b4b4e | 2006-03-28 16:37:06 -0800 | [diff] [blame] | 101 | static int __init ebtable_nat_init(void) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 102 | { |
| 103 | int i, ret, j; |
| 104 | |
| 105 | ret = ebt_register_table(&frame_nat); |
| 106 | if (ret < 0) |
| 107 | return ret; |
| 108 | for (i = 0; i < ARRAY_SIZE(ebt_ops_nat); i++) |
| 109 | if ((ret = nf_register_hook(&ebt_ops_nat[i])) < 0) |
| 110 | goto cleanup; |
| 111 | return ret; |
| 112 | cleanup: |
| 113 | for (j = 0; j < i; j++) |
| 114 | nf_unregister_hook(&ebt_ops_nat[j]); |
| 115 | ebt_unregister_table(&frame_nat); |
| 116 | return ret; |
| 117 | } |
| 118 | |
Andrew Morton | 65b4b4e | 2006-03-28 16:37:06 -0800 | [diff] [blame] | 119 | static void __exit ebtable_nat_fini(void) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 120 | { |
| 121 | int i; |
| 122 | |
| 123 | for (i = 0; i < ARRAY_SIZE(ebt_ops_nat); i++) |
| 124 | nf_unregister_hook(&ebt_ops_nat[i]); |
| 125 | ebt_unregister_table(&frame_nat); |
| 126 | } |
| 127 | |
Andrew Morton | 65b4b4e | 2006-03-28 16:37:06 -0800 | [diff] [blame] | 128 | module_init(ebtable_nat_init); |
| 129 | module_exit(ebtable_nat_fini); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 130 | MODULE_LICENSE("GPL"); |