1 /* 2 * net/sched/em_ipset.c ipset ematch 3 * 4 * Copyright (c) 2012 Florian Westphal <fw@strlen.de> 5 * 6 * This program is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU General Public License 8 * version 2 as published by the Free Software Foundation. 9 */ 10 11 #include <linux/gfp.h> 12 #include <linux/module.h> 13 #include <linux/types.h> 14 #include <linux/kernel.h> 15 #include <linux/string.h> 16 #include <linux/skbuff.h> 17 #include <linux/netfilter/xt_set.h> 18 #include <linux/ipv6.h> 19 #include <net/ip.h> 20 #include <net/pkt_cls.h> 21 22 static int em_ipset_change(struct net *net, void *data, int data_len, 23 struct tcf_ematch *em) 24 { 25 struct xt_set_info *set = data; 26 ip_set_id_t index; 27 28 if (data_len != sizeof(*set)) 29 return -EINVAL; 30 31 index = ip_set_nfnl_get_byindex(net, set->index); 32 if (index == IPSET_INVALID_ID) 33 return -ENOENT; 34 35 em->datalen = sizeof(*set); 36 em->data = (unsigned long)kmemdup(data, em->datalen, GFP_KERNEL); 37 if (em->data) 38 return 0; 39 40 ip_set_nfnl_put(net, index); 41 return -ENOMEM; 42 } 43 44 static void em_ipset_destroy(struct tcf_ematch *em) 45 { 46 const struct xt_set_info *set = (const void *) em->data; 47 if (set) { 48 ip_set_nfnl_put(em->net, set->index); 49 kfree((void *) em->data); 50 } 51 } 52 53 static int em_ipset_match(struct sk_buff *skb, struct tcf_ematch *em, 54 struct tcf_pkt_info *info) 55 { 56 struct ip_set_adt_opt opt; 57 struct xt_action_param acpar; 58 const struct xt_set_info *set = (const void *) em->data; 59 struct net_device *dev, *indev = NULL; 60 struct nf_hook_state state = { 61 .net = em->net, 62 }; 63 int ret, network_offset; 64 65 switch (tc_skb_protocol(skb)) { 66 case htons(ETH_P_IP): 67 state.pf = NFPROTO_IPV4; 68 if (!pskb_network_may_pull(skb, sizeof(struct iphdr))) 69 return 0; 70 acpar.thoff = ip_hdrlen(skb); 71 break; 72 case htons(ETH_P_IPV6): 73 state.pf = NFPROTO_IPV6; 74 if (!pskb_network_may_pull(skb, sizeof(struct ipv6hdr))) 75 return 0; 76 /* doesn't call ipv6_find_hdr() because ipset doesn't use thoff, yet */ 77 acpar.thoff = sizeof(struct ipv6hdr); 78 break; 79 default: 80 return 0; 81 } 82 83 opt.family = state.pf; 84 opt.dim = set->dim; 85 opt.flags = set->flags; 86 opt.cmdflags = 0; 87 opt.ext.timeout = ~0u; 88 89 network_offset = skb_network_offset(skb); 90 skb_pull(skb, network_offset); 91 92 dev = skb->dev; 93 94 rcu_read_lock(); 95 96 if (skb->skb_iif) 97 indev = dev_get_by_index_rcu(em->net, skb->skb_iif); 98 99 state.in = indev ? indev : dev; 100 state.out = dev; 101 acpar.state = &state; 102 103 ret = ip_set_test(set->index, skb, &acpar, &opt); 104 105 rcu_read_unlock(); 106 107 skb_push(skb, network_offset); 108 return ret; 109 } 110 111 static struct tcf_ematch_ops em_ipset_ops = { 112 .kind = TCF_EM_IPSET, 113 .change = em_ipset_change, 114 .destroy = em_ipset_destroy, 115 .match = em_ipset_match, 116 .owner = THIS_MODULE, 117 .link = LIST_HEAD_INIT(em_ipset_ops.link) 118 }; 119 120 static int __init init_em_ipset(void) 121 { 122 return tcf_em_register(&em_ipset_ops); 123 } 124 125 static void __exit exit_em_ipset(void) 126 { 127 tcf_em_unregister(&em_ipset_ops); 128 } 129 130 MODULE_LICENSE("GPL"); 131 MODULE_AUTHOR("Florian Westphal <fw@strlen.de>"); 132 MODULE_DESCRIPTION("TC extended match for IP sets"); 133 134 module_init(init_em_ipset); 135 module_exit(exit_em_ipset); 136 137 MODULE_ALIAS_TCF_EMATCH(TCF_EM_IPSET); 138