From 57f0f512b273f60d52568b8c6b77e17f5636edc0 Mon Sep 17 00:00:00 2001 From: André Fabian Silva Delgado Date: Wed, 5 Aug 2015 17:04:01 -0300 Subject: Initial import --- net/ipv4/netfilter/arptable_filter.c | 91 ++++++++++++++++++++++++++++++++++++ 1 file changed, 91 insertions(+) create mode 100644 net/ipv4/netfilter/arptable_filter.c (limited to 'net/ipv4/netfilter/arptable_filter.c') diff --git a/net/ipv4/netfilter/arptable_filter.c b/net/ipv4/netfilter/arptable_filter.c new file mode 100644 index 000000000..93876d031 --- /dev/null +++ b/net/ipv4/netfilter/arptable_filter.c @@ -0,0 +1,91 @@ +/* + * Filtering ARP tables module. + * + * Copyright (C) 2002 David S. Miller (davem@redhat.com) + * + */ + +#include +#include +#include +#include + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("David S. Miller "); +MODULE_DESCRIPTION("arptables filter table"); + +#define FILTER_VALID_HOOKS ((1 << NF_ARP_IN) | (1 << NF_ARP_OUT) | \ + (1 << NF_ARP_FORWARD)) + +static const struct xt_table packet_filter = { + .name = "filter", + .valid_hooks = FILTER_VALID_HOOKS, + .me = THIS_MODULE, + .af = NFPROTO_ARP, + .priority = NF_IP_PRI_FILTER, +}; + +/* The work comes in here from netfilter.c */ +static unsigned int +arptable_filter_hook(const struct nf_hook_ops *ops, struct sk_buff *skb, + const struct nf_hook_state *state) +{ + const struct net *net = dev_net(state->in ? state->in : state->out); + + return arpt_do_table(skb, ops->hooknum, state, + net->ipv4.arptable_filter); +} + +static struct nf_hook_ops *arpfilter_ops __read_mostly; + +static int __net_init arptable_filter_net_init(struct net *net) +{ + struct arpt_replace *repl; + + repl = arpt_alloc_initial_table(&packet_filter); + if (repl == NULL) + return -ENOMEM; + net->ipv4.arptable_filter = + arpt_register_table(net, &packet_filter, repl); + kfree(repl); + return PTR_ERR_OR_ZERO(net->ipv4.arptable_filter); +} + +static void __net_exit arptable_filter_net_exit(struct net *net) +{ + arpt_unregister_table(net->ipv4.arptable_filter); +} + +static struct pernet_operations arptable_filter_net_ops = { + .init = arptable_filter_net_init, + .exit = arptable_filter_net_exit, +}; + +static int __init arptable_filter_init(void) +{ + int ret; + + ret = register_pernet_subsys(&arptable_filter_net_ops); + if (ret < 0) + return ret; + + arpfilter_ops = xt_hook_link(&packet_filter, arptable_filter_hook); + if (IS_ERR(arpfilter_ops)) { + ret = PTR_ERR(arpfilter_ops); + goto cleanup_table; + } + return ret; + +cleanup_table: + unregister_pernet_subsys(&arptable_filter_net_ops); + return ret; +} + +static void __exit arptable_filter_fini(void) +{ + xt_hook_unlink(&packet_filter, arpfilter_ops); + unregister_pernet_subsys(&arptable_filter_net_ops); +} + +module_init(arptable_filter_init); +module_exit(arptable_filter_fini); -- cgit v1.2.3-54-g00ecf