/* * ebtable_filter * * Authors: * Bart De Schuymer * * April, 2002 * */ #include #include #define FILTER_VALID_HOOKS ((1 << NF_BR_LOCAL_IN) | (1 << NF_BR_FORWARD) | \ (1 << NF_BR_LOCAL_OUT)) static struct ebt_entries initial_chains[] = { {0, "INPUT", 0, EBT_ACCEPT, 0}, {0, "FORWARD", 0, EBT_ACCEPT, 0}, {0, "OUTPUT", 0, EBT_ACCEPT, 0} }; static struct ebt_replace initial_table = { "filter", FILTER_VALID_HOOKS, 0, 3 * sizeof(struct ebt_entries), { [NF_BR_LOCAL_IN]&initial_chains[0], [NF_BR_FORWARD]&initial_chains[1], [NF_BR_LOCAL_OUT]&initial_chains[2] }, 0, NULL, (char *)initial_chains }; static int check(const struct ebt_table_info *info, unsigned int valid_hooks) { if (valid_hooks & ~FILTER_VALID_HOOKS) return -EINVAL; return 0; } static struct ebt_table frame_filter = { {NULL, NULL}, "filter", &initial_table, FILTER_VALID_HOOKS, RW_LOCK_UNLOCKED, check, NULL }; static unsigned int ebt_hook (unsigned int hook, struct sk_buff **pskb, const struct net_device *in, const struct net_device *out, int (*okfn)(struct sk_buff *)) { return ebt_do_table(hook, pskb, in, out, &frame_filter); } static struct nf_hook_ops ebt_ops_filter[] = { { { NULL, NULL }, ebt_hook, PF_BRIDGE, NF_BR_LOCAL_IN, NF_BR_PRI_FILTER_BRIDGED}, { { NULL, NULL }, ebt_hook, PF_BRIDGE, NF_BR_FORWARD, NF_BR_PRI_FILTER_BRIDGED}, { { NULL, NULL }, ebt_hook, PF_BRIDGE, NF_BR_LOCAL_OUT, NF_BR_PRI_FILTER_OTHER} }; static int __init init(void) { int i, j, ret; ret = ebt_register_table(&frame_filter); if (ret < 0) return ret; for (i = 0; i < sizeof(ebt_ops_filter) / sizeof(ebt_ops_filter[0]); i++) if ((ret = nf_register_hook(&ebt_ops_filter[i])) < 0) goto cleanup; return ret; cleanup: for (j = 0; j < i; j++) nf_unregister_hook(&ebt_ops_filter[j]); ebt_unregister_table(&frame_filter); return ret; } static void __exit fini(void) { int i; for (i = 0; i < sizeof(ebt_ops_filter) / sizeof(ebt_ops_filter[0]); i++) nf_unregister_hook(&ebt_ops_filter[i]); ebt_unregister_table(&frame_filter); } module_init(init); module_exit(fini); EXPORT_NO_SYMBOLS; MODULE_LICENSE("GPL");