1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * net/sched/em_ipset.c ipset ematch 4 * 5 * Copyright (c) 2012 Florian Westphal <fw@strlen.de> 6 */ 7 8 #include <linux/gfp.h> 9 #include <linux/module.h> 10 #include <linux/types.h> 11 #include <linux/kernel.h> 12 #include <linux/string.h> 13 #include <linux/skbuff.h> 14 #include <linux/netfilter/xt_set.h> 15 #include <linux/ipv6.h> 16 #include <net/ip.h> 17 #include <net/pkt_cls.h> 18 19 static int em_ipset_change(struct net *net, void *data, int data_len, 20 struct tcf_ematch *em) 21 { 22 struct xt_set_info *set = data; 23 ip_set_id_t index; 24 25 if (data_len != sizeof(*set)) 26 return -EINVAL; 27 28 index = ip_set_nfnl_get_byindex(net, set->index); 29 if (index == IPSET_INVALID_ID) 30 return -ENOENT; 31 32 em->datalen = sizeof(*set); 33 em->data = (unsigned long)kmemdup(data, em->datalen, GFP_KERNEL); 34 if (em->data) 35 return 0; 36 37 ip_set_nfnl_put(net, index); 38 return -ENOMEM; 39 } 40 41 static void em_ipset_destroy(struct tcf_ematch *em) 42 { 43 const struct xt_set_info *set = (const void *) em->data; 44 if (set) { 45 ip_set_nfnl_put(em->net, set->index); 46 kfree((void *) em->data); 47 } 48 } 49 50 static int em_ipset_match(struct sk_buff *skb, struct tcf_ematch *em, 51 struct tcf_pkt_info *info) 52 { 53 struct ip_set_adt_opt opt; 54 struct xt_action_param acpar; 55 const struct xt_set_info *set = (const void *) em->data; 56 struct net_device *dev, *indev = NULL; 57 struct nf_hook_state state = { 58 .net = em->net, 59 }; 60 int ret, network_offset; 61 62 switch (tc_skb_protocol(skb)) { 63 case htons(ETH_P_IP): 64 state.pf = 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 state.pf = 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 opt.family = state.pf; 81 opt.dim = set->dim; 82 opt.flags = set->flags; 83 opt.cmdflags = 0; 84 opt.ext.timeout = ~0u; 85 86 network_offset = skb_network_offset(skb); 87 skb_pull(skb, network_offset); 88 89 dev = skb->dev; 90 91 rcu_read_lock(); 92 93 if (skb->skb_iif) 94 indev = dev_get_by_index_rcu(em->net, skb->skb_iif); 95 96 state.in = indev ? indev : dev; 97 state.out = dev; 98 acpar.state = &state; 99 100 ret = ip_set_test(set->index, skb, &acpar, &opt); 101 102 rcu_read_unlock(); 103 104 skb_push(skb, network_offset); 105 return ret; 106 } 107 108 static struct tcf_ematch_ops em_ipset_ops = { 109 .kind = TCF_EM_IPSET, 110 .change = em_ipset_change, 111 .destroy = em_ipset_destroy, 112 .match = em_ipset_match, 113 .owner = THIS_MODULE, 114 .link = LIST_HEAD_INIT(em_ipset_ops.link) 115 }; 116 117 static int __init init_em_ipset(void) 118 { 119 return tcf_em_register(&em_ipset_ops); 120 } 121 122 static void __exit exit_em_ipset(void) 123 { 124 tcf_em_unregister(&em_ipset_ops); 125 } 126 127 MODULE_LICENSE("GPL"); 128 MODULE_AUTHOR("Florian Westphal <fw@strlen.de>"); 129 MODULE_DESCRIPTION("TC extended match for IP sets"); 130 131 module_init(init_em_ipset); 132 module_exit(exit_em_ipset); 133 134 MODULE_ALIAS_TCF_EMATCH(TCF_EM_IPSET); 135