Beispiel #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;
}
Beispiel #2
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;
}
Beispiel #3
0
static int
xt_ct_set_timeout(struct nf_conn *ct, const struct xt_tgchk_param *par,
		  const char *timeout_name)
{
#ifdef CONFIG_NF_CONNTRACK_TIMEOUT
	typeof(nf_ct_timeout_find_get_hook) timeout_find_get;
	struct ctnl_timeout *timeout;
	struct nf_conn_timeout *timeout_ext;
	struct nf_conntrack_l4proto *l4proto;
	int ret = 0;
	u8 proto;

	rcu_read_lock();
	timeout_find_get = rcu_dereference(nf_ct_timeout_find_get_hook);
	if (timeout_find_get == NULL) {
		ret = -ENOENT;
		pr_info("Timeout policy base is empty\n");
		goto out;
	}

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

	timeout = timeout_find_get(timeout_name);
	if (timeout == NULL) {
		ret = -ENOENT;
		pr_info("No such timeout policy \"%s\"\n", timeout_name);
		goto out;
	}

	if (timeout->l3num != par->family) {
		ret = -EINVAL;
		pr_info("Timeout policy `%s' can only be used by L3 protocol "
			"number %d\n", timeout_name, timeout->l3num);
		goto err_put_timeout;
	}
	/* Make sure the timeout policy matches any existing protocol tracker,
	 * otherwise default to generic.
	 */
	l4proto = __nf_ct_l4proto_find(par->family, proto);
	if (timeout->l4proto->l4proto != l4proto->l4proto) {
		ret = -EINVAL;
		pr_info("Timeout policy `%s' can only be used by L4 protocol "
			"number %d\n",
			timeout_name, timeout->l4proto->l4proto);
		goto err_put_timeout;
	}
	timeout_ext = nf_ct_timeout_ext_add(ct, timeout, GFP_ATOMIC);
	if (timeout_ext == NULL)
		ret = -ENOMEM;

err_put_timeout:
	__xt_ct_tg_timeout_put(timeout);
out:
	rcu_read_unlock();
	return ret;
#else
	return -EOPNOTSUPP;
#endif
}
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;
}