1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * 'raw' table, which is the very first hooked in at PRE_ROUTING and LOCAL_OUT . 4 * 5 * Copyright (C) 2003 Jozsef Kadlecsik <kadlec@netfilter.org> 6 */ 7 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 8 #include <linux/module.h> 9 #include <linux/netfilter_ipv4/ip_tables.h> 10 #include <linux/slab.h> 11 #include <net/ip.h> 12 13 #define RAW_VALID_HOOKS ((1 << NF_INET_PRE_ROUTING) | (1 << NF_INET_LOCAL_OUT)) 14 15 static bool raw_before_defrag __read_mostly; 16 MODULE_PARM_DESC(raw_before_defrag, "Enable raw table before defrag"); 17 module_param(raw_before_defrag, bool, 0000); 18 19 static const struct xt_table packet_raw = { 20 .name = "raw", 21 .valid_hooks = RAW_VALID_HOOKS, 22 .me = THIS_MODULE, 23 .af = NFPROTO_IPV4, 24 .priority = NF_IP_PRI_RAW, 25 }; 26 27 static const struct xt_table packet_raw_before_defrag = { 28 .name = "raw", 29 .valid_hooks = RAW_VALID_HOOKS, 30 .me = THIS_MODULE, 31 .af = NFPROTO_IPV4, 32 .priority = NF_IP_PRI_RAW_BEFORE_DEFRAG, 33 }; 34 35 static struct nf_hook_ops *rawtable_ops __read_mostly; 36 37 static int iptable_raw_table_init(struct net *net) 38 { 39 struct ipt_replace *repl; 40 const struct xt_table *table = &packet_raw; 41 int ret; 42 43 if (raw_before_defrag) 44 table = &packet_raw_before_defrag; 45 46 repl = ipt_alloc_initial_table(table); 47 if (repl == NULL) 48 return -ENOMEM; 49 ret = ipt_register_table(net, table, repl, rawtable_ops); 50 kfree(repl); 51 return ret; 52 } 53 54 static void __net_exit iptable_raw_net_pre_exit(struct net *net) 55 { 56 ipt_unregister_table_pre_exit(net, "raw"); 57 } 58 59 static void __net_exit iptable_raw_net_exit(struct net *net) 60 { 61 ipt_unregister_table_exit(net, "raw"); 62 } 63 64 static struct pernet_operations iptable_raw_net_ops = { 65 .pre_exit = iptable_raw_net_pre_exit, 66 .exit = iptable_raw_net_exit, 67 }; 68 69 static int __init iptable_raw_init(void) 70 { 71 int ret; 72 const struct xt_table *table = &packet_raw; 73 74 if (raw_before_defrag) { 75 table = &packet_raw_before_defrag; 76 77 pr_info("Enabling raw table before defrag\n"); 78 } 79 80 ret = xt_register_template(table, 81 iptable_raw_table_init); 82 if (ret < 0) 83 return ret; 84 85 rawtable_ops = xt_hook_ops_alloc(table, ipt_do_table); 86 if (IS_ERR(rawtable_ops)) { 87 xt_unregister_template(table); 88 return PTR_ERR(rawtable_ops); 89 } 90 91 ret = register_pernet_subsys(&iptable_raw_net_ops); 92 if (ret < 0) { 93 xt_unregister_template(table); 94 kfree(rawtable_ops); 95 return ret; 96 } 97 98 return ret; 99 } 100 101 static void __exit iptable_raw_fini(void) 102 { 103 unregister_pernet_subsys(&iptable_raw_net_ops); 104 kfree(rawtable_ops); 105 xt_unregister_template(&packet_raw); 106 } 107 108 module_init(iptable_raw_init); 109 module_exit(iptable_raw_fini); 110 MODULE_LICENSE("GPL"); 111