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 int ret, network_offset; 61 62 switch (tc_skb_protocol(skb)) { 63 case htons(ETH_P_IP): 64 acpar.family = NFPROTO_IPV4; 65 if (!pskb_network_may_pull(skb, sizeof(struct iphdr))) 66 return 0; 67 acpar.thoff = ip_hdrlen(skb); 68 break; 69 case htons(ETH_P_IPV6): 70 acpar.family = NFPROTO_IPV6; 71 if (!pskb_network_may_pull(skb, sizeof(struct ipv6hdr))) 72 return 0; 73 /* doesn't call ipv6_find_hdr() because ipset doesn't use thoff, yet */ 74 acpar.thoff = sizeof(struct ipv6hdr); 75 break; 76 default: 77 return 0; 78 } 79 80 acpar.hooknum = 0; 81 82 opt.family = acpar.family; 83 opt.dim = set->dim; 84 opt.flags = set->flags; 85 opt.cmdflags = 0; 86 opt.ext.timeout = ~0u; 87 88 network_offset = skb_network_offset(skb); 89 skb_pull(skb, network_offset); 90 91 dev = skb->dev; 92 93 rcu_read_lock(); 94 95 if (skb->skb_iif) 96 indev = dev_get_by_index_rcu(em->net, skb->skb_iif); 97 98 acpar.net = em->net; 99 acpar.in = indev ? indev : dev; 100 acpar.out = dev; 101 102 ret = ip_set_test(set->index, skb, &acpar, &opt); 103 104 rcu_read_unlock(); 105 106 skb_push(skb, network_offset); 107 return ret; 108 } 109 110 static struct tcf_ematch_ops em_ipset_ops = { 111 .kind = TCF_EM_IPSET, 112 .change = em_ipset_change, 113 .destroy = em_ipset_destroy, 114 .match = em_ipset_match, 115 .owner = THIS_MODULE, 116 .link = LIST_HEAD_INIT(em_ipset_ops.link) 117 }; 118 119 static int __init init_em_ipset(void) 120 { 121 return tcf_em_register(&em_ipset_ops); 122 } 123 124 static void __exit exit_em_ipset(void) 125 { 126 tcf_em_unregister(&em_ipset_ops); 127 } 128 129 MODULE_LICENSE("GPL"); 130 MODULE_AUTHOR("Florian Westphal <fw@strlen.de>"); 131 MODULE_DESCRIPTION("TC extended match for IP sets"); 132 133 module_init(init_em_ipset); 134 module_exit(exit_em_ipset); 135 136 MODULE_ALIAS_TCF_EMATCH(TCF_EM_IPSET); 137