Exemplo n.º 1
0
static int
xt_ct_set_helper(struct nf_conn *ct, const char *helper_name,
		 const struct xt_tgchk_param *par)
{
	struct nf_conntrack_helper *helper;
	struct nf_conn_help *help;
	u8 proto;

	proto = xt_ct_find_proto(par);
	if (!proto) {
		pr_info("You must specify a L4 protocol, and not use "
			"inversions on it.\n");
		return -ENOENT;
	}

	helper = nf_conntrack_helper_try_module_get(helper_name, par->family,
						    proto);
	if (helper == NULL) {
		pr_info("No such helper \"%s\"\n", helper_name);
		return -ENOENT;
	}

	help = nf_ct_helper_ext_add(ct, helper, GFP_KERNEL);
	if (help == NULL) {
		module_put(helper->me);
		return -ENOMEM;
	}

	help->helper = helper;
	return 0;
}
Exemplo n.º 2
0
static int ovs_ct_add_helper(struct ovs_conntrack_info *info, const char *name,
			     const struct sw_flow_key *key, bool log)
{
	struct nf_conntrack_helper *helper;
	struct nf_conn_help *help;

	helper = nf_conntrack_helper_try_module_get(name, info->family,
						    key->ip.proto);
	if (!helper) {
		OVS_NLERR(log, "Unknown helper \"%s\"", name);
		return -EINVAL;
	}

	help = nf_ct_helper_ext_add(info->ct, helper, GFP_KERNEL);
	if (!help) {
		module_put(helper->me);
		return -ENOMEM;
	}

	rcu_assign_pointer(help->helper, helper);
	info->helper = helper;
	return 0;
}
Exemplo n.º 3
0
static int xt_ct_tg_check(const struct xt_tgchk_param *par)
{
    struct xt_ct_target_info *info = par->targinfo;
    struct nf_conntrack_tuple t;
    struct nf_conn_help *help;
    struct nf_conn *ct;
    int ret = 0;
    u8 proto;

    if (info->flags & ~XT_CT_NOTRACK)
        return -EINVAL;

    if (info->flags & XT_CT_NOTRACK) {
        ct = nf_ct_untracked_get();
        atomic_inc(&ct->ct_general.use);
        goto out;
    }

#ifndef CONFIG_NF_CONNTRACK_ZONES
    if (info->zone)
        goto err1;
#endif

    ret = nf_ct_l3proto_try_module_get(par->family);
    if (ret < 0)
        goto err1;

    memset(&t, 0, sizeof(t));
    ct = nf_conntrack_alloc(par->net, info->zone, &t, &t, GFP_KERNEL);
    ret = PTR_ERR(ct);
    if (IS_ERR(ct))
        goto err2;

    ret = 0;
    if ((info->ct_events || info->exp_events) &&
            !nf_ct_ecache_ext_add(ct, info->ct_events, info->exp_events,
                                  GFP_KERNEL))
        goto err3;

    if (info->helper[0]) {
        ret = -ENOENT;
        proto = xt_ct_find_proto(par);
        if (!proto)
            goto err3;

        ret = -ENOMEM;
        help = nf_ct_helper_ext_add(ct, GFP_KERNEL);
        if (help == NULL)
            goto err3;

        ret = -ENOENT;
        help->helper = nf_conntrack_helper_try_module_get(info->helper,
                       par->family,
                       proto);
        if (help->helper == NULL)
            goto err3;
    }

    __set_bit(IPS_TEMPLATE_BIT, &ct->status);
    __set_bit(IPS_CONFIRMED_BIT, &ct->status);
out:
    info->ct = ct;
    return 0;

err3:
    nf_conntrack_free(ct);
err2:
    nf_ct_l3proto_module_put(par->family);
err1:
    return ret;
}
Exemplo n.º 4
0
static unsigned int
conenat_tg(struct sk_buff *skb, const struct xt_target_param *par)
{
       struct net *net;
	struct nf_conn *ct;
       struct nf_conn_nat *nat;
	enum ip_conntrack_info ctinfo;
	struct nf_nat_range newrange;
       const struct nf_nat_multi_range_compat *mr;
	struct rtable *rt;
	__be32 newsrc;

	NF_CT_ASSERT(par->hooknum == NF_INET_POST_ROUTING);

	ct = nf_ct_get(skb, &ctinfo);
	nat = nfct_nat(ct);
   	net = nf_ct_net(ct);

	NF_CT_ASSERT(ct && (ctinfo == IP_CT_NEW || ctinfo == IP_CT_RELATED
			    || ctinfo == IP_CT_RELATED + IP_CT_IS_REPLY));


    /* Source address is 0.0.0.0 - locally generated packet that is
     * probably not supposed to be masqueraded.
     */
	 if (ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.u3.ip == 0)
	        return NF_ACCEPT;

    	mr = par->targinfo;
    	rt = skb->rtable;
    	newsrc = inet_select_addr(par->out, rt->rt_gateway, RT_SCOPE_UNIVERSE);
    	if (!newsrc) {
        	printk("CONENAT: %s ate my IP address\n", par->out->name);
        	return NF_DROP;
    	}

       write_lock_bh(&conenat_lock);
	nat->masq_index = par->out->ifindex;
	write_unlock_bh(&conenat_lock);

	if (ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum == IPPROTO_UDP)
	{
		unsigned int ret,expectcount = net->ct.expect_count;
		u_int16_t minport, maxport;
		u_int16_t newport, tmpport;
		struct nf_conntrack_expect *exp=NULL;
              struct nf_conntrack_tuple tuple;
              struct nf_conn_help *help = nfct_help(ct);

		/* Choose port */
		spin_lock_bh(&nf_conntrack_lock);

       		#if 0
		exp = LIST_FIND(&nf_conntrack_expect_list,
                exp_src_cmp,
				struct nf_conntrack_expect *,
				&ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple);
        	#endif

		memset(&tuple,0,sizeof(tuple));

		//src
		tuple.src.l3num = ct->tuplehash[IP_CT_DIR_REPLY].tuple.src.l3num;
		tuple.src.u3.ip = ct->tuplehash[IP_CT_DIR_REPLY].tuple.src.u3.ip;
		tuple.src.u.udp.port = ct->tuplehash[IP_CT_DIR_REPLY].tuple.src.u.udp.port;

        	//dst
              tuple.dst.u3.ip = newsrc;
		//tuple.dst.u.udp.port = htons(ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.u.udp.port);
		newport = htons(ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.u.udp.port);
		tuple.dst.protonum = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum;

		pr_debug("tupple1 = %pI4:%hu\n", &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.u3.ip,ntohs(ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.u.udp.port));


		if(expectcount > 0){
			for(tmpport=0; (tmpport<=expectcount)&&(newport<=65535); tmpport++,newport++){
				tuple.dst.u.udp.port=newport;
				exp = __nf_ct_expect_find_bysave(net, &tuple, &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple);
				if(exp)
					break;
			}
		}

		if (exp) {
			minport = maxport = exp->tuple.dst.u.udp.port;
			pr_debug("existing mapped port = %hu\n", ntohs(minport));
		} else {


			minport = mr->range[0].min.udp.port == 0 ?
				ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.u.udp.port :
				mr->range[0].min.udp.port;

			maxport = mr->range[0].max.udp.port == 0 ?
				htons(65535) :
				mr->range[0].max.udp.port;

			for (newport = ntohs(minport),tmpport = ntohs(maxport);
			     newport <= tmpport; newport++) {
                #if 0
                exp = LIST_FIND(&ip_conntrack_expect_list,
					       exp_cmp,
					       struct nf_conntrack_expect *,
					       newsrc, htons(newport), ct->tuplehash[IP_CT_DIR_ORIGINAL].
					       tuple.dst.protonum);
                #endif

				//dst
			tuple.dst.u.udp.port = htons(newport);

               	 exp = __nf_ct_expect_find(net, &tuple);
		        if (!exp)
			{
				pr_debug("new mapping: %pI4:%hu -> %pI4:%hu\n",
                    &(ct->tuplehash[IP_CT_DIR_REPLY].tuple.src.u3.ip),
                    ntohs(ct->tuplehash[IP_CT_DIR_REPLY].tuple.src.u.udp.port),
                    &newsrc,  newport);
				minport = maxport = htons(newport);
				break;
			}
			}
		}
		spin_unlock_bh(&nf_conntrack_lock);

		newrange.flags = mr->range[0].flags | IP_NAT_RANGE_MAP_IPS |IP_NAT_RANGE_PROTO_SPECIFIED;
		newrange.min_ip = newrange.max_ip = newsrc;
		newrange.min.udp.port = minport;
		newrange.max.udp.port = maxport;

		/* Set ct helper */
		ret = nf_nat_setup_info(ct, &newrange, IP_NAT_MANIP_SRC);
		if (ret == NF_ACCEPT)
	        {
	            rcu_read_lock();
	            if (help == NULL) {
	                help = nf_ct_helper_ext_add(ct, GFP_ATOMIC);
	                if (help == NULL) {
	                    return NF_ACCEPT;
	                }
	            } else {
	                memset(&help->help, 0, sizeof(help->help));
	            }
	            rcu_assign_pointer(help->helper, &nf_conntrack_helper_cone_nat);
	            rcu_read_unlock();

		    pr_debug("helper setup, skb=%p\n", skb);
		}

		return ret;
	}
Exemplo n.º 5
0
unsigned int rtl_find_appropriate_newrange(struct nf_conn *ct, __be32 newsrc, const struct nf_nat_multi_range_compat *mr)
{
	struct net *net;
	unsigned int ret,expectcount = net->ct.expect_count;
	u_int16_t minport, maxport;
	u_int16_t newport, tmpport;
	struct nf_conntrack_expect *exp=NULL;
	struct nf_conntrack_tuple tuple;
	struct nf_nat_range newrange;
	struct nf_conn_help *help = nfct_help(ct);

	net = nf_ct_net(ct);
	expectcount = net->ct.expect_count;
	/* Choose port */
	spin_lock_bh(&nf_conntrack_lock);

	#if 0
	exp = LIST_FIND(&nf_conntrack_expect_list,
			exp_src_cmp,
			struct nf_conntrack_expect *,
			&ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple);
	#endif

	memset(&tuple,0,sizeof(tuple));

	//src
	tuple.src.l3num = ct->tuplehash[IP_CT_DIR_REPLY].tuple.src.l3num;
	tuple.src.u3.ip = ct->tuplehash[IP_CT_DIR_REPLY].tuple.src.u3.ip;
	tuple.src.u.udp.port = ct->tuplehash[IP_CT_DIR_REPLY].tuple.src.u.udp.port;

	//dst
	tuple.dst.u3.ip = newsrc;
	//tuple.dst.u.udp.port = htons(ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.u.udp.port);
	newport = htons(ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.u.udp.port);
	tuple.dst.protonum = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum;

	pr_debug("tupple1 = %pI4:%hu\n", &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.u3.ip,ntohs(ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.u.udp.port));

	if(expectcount > 0){
		for(tmpport=0; (tmpport<=expectcount)&&(newport<=65535); tmpport++,newport++){
			tuple.dst.u.udp.port=newport;
			exp = __nf_ct_expect_find_bysave(net, &tuple, &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple);
			if(exp)
				break;
		}
	}

	if (exp) {
		minport = maxport = exp->tuple.dst.u.udp.port;
		pr_debug("existing mapped port = %hu\n", ntohs(minport));
	} else {


		minport = mr->range[0].min.udp.port == 0 ?
			ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.u.udp.port :
			mr->range[0].min.udp.port;

		maxport = mr->range[0].max.udp.port == 0 ?
			htons(65535) :
			mr->range[0].max.udp.port;

		for (newport = ntohs(minport),tmpport = ntohs(maxport);
			 newport <= tmpport; newport++) {
        #if 0
			exp = LIST_FIND(&ip_conntrack_expect_list,
					   exp_cmp,
					   struct nf_conntrack_expect *,
					   newsrc, htons(newport), ct->tuplehash[IP_CT_DIR_ORIGINAL].
					   tuple.dst.protonum);
        #endif

			//dst
		tuple.dst.u.udp.port = htons(newport);

			 exp = __nf_ct_expect_find(net, &tuple);
			if (!exp)
			{
				pr_debug("new mapping: %pI4:%hu -> %pI4:%hu\n",
					&(ct->tuplehash[IP_CT_DIR_REPLY].tuple.src.u3.ip),
					ntohs(ct->tuplehash[IP_CT_DIR_REPLY].tuple.src.u.udp.port),
					&newsrc,  newport);
				minport = maxport = htons(newport);
				break;
			}
		}
	}
	spin_unlock_bh(&nf_conntrack_lock);

	newrange.flags = mr->range[0].flags | IP_NAT_RANGE_MAP_IPS |IP_NAT_RANGE_PROTO_SPECIFIED;
	newrange.min_ip = newrange.max_ip = newsrc;
	newrange.min.udp.port = minport;
	newrange.max.udp.port = maxport;

	/* Set ct helper */
	ret = nf_nat_setup_info(ct, &newrange, IP_NAT_MANIP_SRC);
	if (ret == NF_ACCEPT)
        {
            rcu_read_lock();
            if (help == NULL) {
                help = nf_ct_helper_ext_add(ct, GFP_ATOMIC);
                if (help == NULL) {
                    return NF_ACCEPT;
                }
            } else {
                memset(&help->help, 0, sizeof(help->help));
            }
            rcu_assign_pointer(help->helper, &nf_conntrack_helper_cone_nat);
            rcu_read_unlock();
	}

	return ret;
}
Exemplo n.º 6
0
static int xt_ct_tg_check_v1(const struct xt_tgchk_param *par)
{
	struct xt_ct_target_info_v1 *info = par->targinfo;
	struct nf_conntrack_tuple t;
	struct nf_conn_help *help;
	struct nf_conn *ct;
	int ret = 0;
	u8 proto;
#ifdef CONFIG_NF_CONNTRACK_TIMEOUT
	struct ctnl_timeout *timeout;
#endif
	if (info->flags & ~XT_CT_NOTRACK)
		return -EINVAL;

	if (info->flags & XT_CT_NOTRACK) {
		ct = nf_ct_untracked_get();
		atomic_inc(&ct->ct_general.use);
		goto out;
	}

#ifndef CONFIG_NF_CONNTRACK_ZONES
	if (info->zone)
		goto err1;
#endif

	ret = nf_ct_l3proto_try_module_get(par->family);
	if (ret < 0)
		goto err1;

	memset(&t, 0, sizeof(t));
	ct = nf_conntrack_alloc(par->net, info->zone, &t, &t, GFP_KERNEL);
	ret = PTR_ERR(ct);
	if (IS_ERR(ct))
		goto err2;

	ret = 0;
	if ((info->ct_events || info->exp_events) &&
	    !nf_ct_ecache_ext_add(ct, info->ct_events, info->exp_events,
				  GFP_KERNEL))
		goto err3;

	if (info->helper[0]) {
		ret = -ENOENT;
		proto = xt_ct_find_proto(par);
		if (!proto) {
			pr_info("You must specify a L4 protocol, "
				"and not use inversions on it.\n");
			goto err3;
		}

		ret = -ENOMEM;
		help = nf_ct_helper_ext_add(ct, GFP_KERNEL);
		if (help == NULL)
			goto err3;

		ret = -ENOENT;
		help->helper = nf_conntrack_helper_try_module_get(info->helper,
								  par->family,
								  proto);
		if (help->helper == NULL) {
			pr_info("No such helper \"%s\"\n", info->helper);
			goto err3;
		}
	}

#ifdef CONFIG_NF_CONNTRACK_TIMEOUT
	if (info->timeout[0]) {
		typeof(nf_ct_timeout_find_get_hook) timeout_find_get;
		struct nf_conn_timeout *timeout_ext;

		rcu_read_lock();
		timeout_find_get =
			rcu_dereference(nf_ct_timeout_find_get_hook);

		if (timeout_find_get) {
			const struct ipt_entry *e = par->entryinfo;
			struct nf_conntrack_l4proto *l4proto;

			if (e->ip.invflags & IPT_INV_PROTO) {
				ret = -EINVAL;
				pr_info("You cannot use inversion on "
					 "L4 protocol\n");
				goto err4;
			}
			timeout = timeout_find_get(info->timeout);
			if (timeout == NULL) {
				ret = -ENOENT;
				pr_info("No such timeout policy \"%s\"\n",
					info->timeout);
				goto err4;
			}
			if (timeout->l3num != par->family) {
				ret = -EINVAL;
				pr_info("Timeout policy `%s' can only be "
					"used by L3 protocol number %d\n",
					info->timeout, timeout->l3num);
				goto err5;
			}
			/* Make sure the timeout policy matches any existing
			 * protocol tracker, otherwise default to generic.
			 */
			l4proto = __nf_ct_l4proto_find(par->family,
						       e->ip.proto);
			if (timeout->l4proto->l4proto != l4proto->l4proto) {
				ret = -EINVAL;
				pr_info("Timeout policy `%s' can only be "
					"used by L4 protocol number %d\n",
					info->timeout,
					timeout->l4proto->l4proto);
				goto err5;
			}
			timeout_ext = nf_ct_timeout_ext_add(ct, timeout,
							    GFP_ATOMIC);
			if (timeout_ext == NULL) {
				ret = -ENOMEM;
				goto err5;
			}
		} else {
			ret = -ENOENT;
			pr_info("Timeout policy base is empty\n");
			goto err4;
		}
		rcu_read_unlock();
	}
#endif

	__set_bit(IPS_TEMPLATE_BIT, &ct->status);
	__set_bit(IPS_CONFIRMED_BIT, &ct->status);
out:
	info->ct = ct;
	return 0;

#ifdef CONFIG_NF_CONNTRACK_TIMEOUT
err5:
	__xt_ct_tg_timeout_put(timeout);
err4:
	rcu_read_unlock();
#endif
err3:
	nf_conntrack_free(ct);
err2:
	nf_ct_l3proto_module_put(par->family);
err1:
	return ret;
}