diff options
Diffstat (limited to 'net/ipv4/netfilter/arptable_filter.c')
-rw-r--r-- | net/ipv4/netfilter/arptable_filter.c | 91 |
1 files changed, 91 insertions, 0 deletions
diff --git a/net/ipv4/netfilter/arptable_filter.c b/net/ipv4/netfilter/arptable_filter.c new file mode 100644 index 0000000000..78cd5ee244 --- /dev/null +++ b/net/ipv4/netfilter/arptable_filter.c @@ -0,0 +1,91 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Filtering ARP tables module. + * + * Copyright (C) 2002 David S. Miller (davem@redhat.com) + * + */ + +#include <linux/module.h> +#include <linux/netfilter/x_tables.h> +#include <linux/netfilter_arp/arp_tables.h> +#include <linux/slab.h> + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("David S. Miller <davem@redhat.com>"); +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, +}; + +static struct nf_hook_ops *arpfilter_ops __read_mostly; + +static int arptable_filter_table_init(struct net *net) +{ + struct arpt_replace *repl; + int err; + + repl = arpt_alloc_initial_table(&packet_filter); + if (repl == NULL) + return -ENOMEM; + err = arpt_register_table(net, &packet_filter, repl, arpfilter_ops); + kfree(repl); + return err; +} + +static void __net_exit arptable_filter_net_pre_exit(struct net *net) +{ + arpt_unregister_table_pre_exit(net, "filter"); +} + +static void __net_exit arptable_filter_net_exit(struct net *net) +{ + arpt_unregister_table(net, "filter"); +} + +static struct pernet_operations arptable_filter_net_ops = { + .exit = arptable_filter_net_exit, + .pre_exit = arptable_filter_net_pre_exit, +}; + +static int __init arptable_filter_init(void) +{ + int ret = xt_register_template(&packet_filter, + arptable_filter_table_init); + + if (ret < 0) + return ret; + + arpfilter_ops = xt_hook_ops_alloc(&packet_filter, arpt_do_table); + if (IS_ERR(arpfilter_ops)) { + xt_unregister_template(&packet_filter); + return PTR_ERR(arpfilter_ops); + } + + ret = register_pernet_subsys(&arptable_filter_net_ops); + if (ret < 0) { + xt_unregister_template(&packet_filter); + kfree(arpfilter_ops); + return ret; + } + + return ret; +} + +static void __exit arptable_filter_fini(void) +{ + unregister_pernet_subsys(&arptable_filter_net_ops); + xt_unregister_template(&packet_filter); + kfree(arpfilter_ops); +} + +module_init(arptable_filter_init); +module_exit(arptable_filter_fini); |