 6d4fa852a0
			
		
	
	
	6d4fa852a0
	
	
	
		
			
			Can be used to match packets against netfilter ip sets created via ipset(8). skb->sk_iif is used as 'incoming interface', skb->dev is 'outgoing interface'. Since ipset is usually called from netfilter, the ematch initializes a fake xt_action_param, pulls the ip header into the linear area and also sets skb->data to the IP header (otherwise matching Layer 4 set types doesn't work). Tested-by: Mr Dash Four <mr.dash.four@googlemail.com> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
		
			
				
	
	
		
			135 lines
		
	
	
	
		
			3.1 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			135 lines
		
	
	
	
		
			3.1 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * net/sched/em_ipset.c	ipset ematch
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|  *
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|  * Copyright (c) 2012 Florian Westphal <fw@strlen.de>
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|  *
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|  * This program is free software; you can redistribute it and/or
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|  * modify it under the terms of the GNU General Public License
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|  * version 2 as published by the Free Software Foundation.
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|  */
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| 
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| #include <linux/gfp.h>
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| #include <linux/module.h>
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| #include <linux/types.h>
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| #include <linux/kernel.h>
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| #include <linux/string.h>
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| #include <linux/skbuff.h>
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| #include <linux/netfilter/xt_set.h>
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| #include <linux/ipv6.h>
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| #include <net/ip.h>
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| #include <net/pkt_cls.h>
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| 
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| static int em_ipset_change(struct tcf_proto *tp, void *data, int data_len,
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| 			   struct tcf_ematch *em)
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| {
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| 	struct xt_set_info *set = data;
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| 	ip_set_id_t index;
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| 
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| 	if (data_len != sizeof(*set))
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| 		return -EINVAL;
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| 
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| 	index = ip_set_nfnl_get_byindex(set->index);
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| 	if (index == IPSET_INVALID_ID)
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| 		return -ENOENT;
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| 
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| 	em->datalen = sizeof(*set);
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| 	em->data = (unsigned long)kmemdup(data, em->datalen, GFP_KERNEL);
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| 	if (em->data)
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| 		return 0;
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| 
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| 	ip_set_nfnl_put(index);
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| 	return -ENOMEM;
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| }
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| 
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| static void em_ipset_destroy(struct tcf_proto *p, struct tcf_ematch *em)
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| {
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| 	const struct xt_set_info *set = (const void *) em->data;
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| 	if (set) {
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| 		ip_set_nfnl_put(set->index);
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| 		kfree((void *) em->data);
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| 	}
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| }
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| 
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| static int em_ipset_match(struct sk_buff *skb, struct tcf_ematch *em,
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| 			  struct tcf_pkt_info *info)
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| {
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| 	struct ip_set_adt_opt opt;
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| 	struct xt_action_param acpar;
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| 	const struct xt_set_info *set = (const void *) em->data;
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| 	struct net_device *dev, *indev = NULL;
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| 	int ret, network_offset;
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| 
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| 	switch (skb->protocol) {
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| 	case htons(ETH_P_IP):
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| 		acpar.family = NFPROTO_IPV4;
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| 		if (!pskb_network_may_pull(skb, sizeof(struct iphdr)))
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| 			return 0;
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| 		acpar.thoff = ip_hdrlen(skb);
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| 		break;
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| 	case htons(ETH_P_IPV6):
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| 		acpar.family = NFPROTO_IPV6;
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| 		if (!pskb_network_may_pull(skb, sizeof(struct ipv6hdr)))
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| 			return 0;
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| 		/* doesn't call ipv6_find_hdr() because ipset doesn't use thoff, yet */
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| 		acpar.thoff = sizeof(struct ipv6hdr);
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| 		break;
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| 	default:
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| 		return 0;
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| 	}
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| 
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| 	acpar.hooknum = 0;
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| 
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| 	opt.family = acpar.family;
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| 	opt.dim = set->dim;
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| 	opt.flags = set->flags;
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| 	opt.cmdflags = 0;
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| 	opt.timeout = ~0u;
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| 
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| 	network_offset = skb_network_offset(skb);
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| 	skb_pull(skb, network_offset);
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| 
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| 	dev = skb->dev;
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| 
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| 	rcu_read_lock();
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| 
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| 	if (dev && skb->skb_iif)
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| 		indev = dev_get_by_index_rcu(dev_net(dev), skb->skb_iif);
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| 
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| 	acpar.in      = indev ? indev : dev;
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| 	acpar.out     = dev;
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| 
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| 	ret = ip_set_test(set->index, skb, &acpar, &opt);
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| 
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| 	rcu_read_unlock();
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| 
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| 	skb_push(skb, network_offset);
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| 	return ret;
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| }
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| 
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| static struct tcf_ematch_ops em_ipset_ops = {
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| 	.kind	  = TCF_EM_IPSET,
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| 	.change	  = em_ipset_change,
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| 	.destroy  = em_ipset_destroy,
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| 	.match	  = em_ipset_match,
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| 	.owner	  = THIS_MODULE,
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| 	.link	  = LIST_HEAD_INIT(em_ipset_ops.link)
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| };
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| 
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| static int __init init_em_ipset(void)
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| {
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| 	return tcf_em_register(&em_ipset_ops);
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| }
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| 
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| static void __exit exit_em_ipset(void)
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| {
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| 	tcf_em_unregister(&em_ipset_ops);
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| }
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| 
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| MODULE_LICENSE("GPL");
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| MODULE_AUTHOR("Florian Westphal <fw@strlen.de>");
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| MODULE_DESCRIPTION("TC extended match for IP sets");
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| 
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| module_init(init_em_ipset);
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| module_exit(exit_em_ipset);
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| 
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| MODULE_ALIAS_TCF_EMATCH(TCF_EM_IPSET);
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