Example #1
0
static u32 __nft_fib6_eval_type(const struct nft_fib *priv,
				const struct nft_pktinfo *pkt)
{
	const struct net_device *dev = NULL;
	const struct nf_ipv6_ops *v6ops;
	const struct nf_afinfo *afinfo;
	int route_err, addrtype;
	struct rt6_info *rt;
	struct flowi6 fl6 = {
		.flowi6_iif = LOOPBACK_IFINDEX,
		.flowi6_proto = pkt->tprot,
	};
	u32 ret = 0;

	afinfo = nf_get_afinfo(NFPROTO_IPV6);
	if (!afinfo)
		return RTN_UNREACHABLE;

	if (priv->flags & NFTA_FIB_F_IIF)
		dev = nft_in(pkt);
	else if (priv->flags & NFTA_FIB_F_OIF)
		dev = nft_out(pkt);

	nft_fib6_flowi_init(&fl6, priv, pkt, dev);

	v6ops = nf_get_ipv6_ops();
	if (dev && v6ops && v6ops->chk_addr(nft_net(pkt), &fl6.daddr, dev, true))
		ret = RTN_LOCAL;

	route_err = afinfo->route(nft_net(pkt), (struct dst_entry **)&rt,
				  flowi6_to_flowi(&fl6), false);
	if (route_err)
		goto err;

	if (rt->rt6i_flags & RTF_REJECT) {
		route_err = rt->dst.error;
		dst_release(&rt->dst);
		goto err;
	}

	if (ipv6_anycast_destination((struct dst_entry *)rt, &fl6.daddr))
		ret = RTN_ANYCAST;
	else if (!dev && rt->rt6i_flags & RTF_LOCAL)
		ret = RTN_LOCAL;

	dst_release(&rt->dst);

	if (ret)
		return ret;

	addrtype = ipv6_addr_type(&fl6.daddr);

	if (addrtype & IPV6_ADDR_MULTICAST)
		return RTN_MULTICAST;
	if (addrtype & IPV6_ADDR_UNICAST)
		return RTN_UNICAST;

	return RTN_UNSPEC;
 err:
	switch (route_err) {
	case -EINVAL:
		return RTN_BLACKHOLE;
	case -EACCES:
		return RTN_PROHIBIT;
	case -EAGAIN:
		return RTN_THROW;
	default:
		break;
	}

	return RTN_UNREACHABLE;
}

void nft_fib6_eval_type(const struct nft_expr *expr, struct nft_regs *regs,
			const struct nft_pktinfo *pkt)
{
	const struct nft_fib *priv = nft_expr_priv(expr);
	u32 *dest = &regs->data[priv->dreg];

	*dest = __nft_fib6_eval_type(priv, pkt);
}
EXPORT_SYMBOL_GPL(nft_fib6_eval_type);

void nft_fib6_eval(const struct nft_expr *expr, struct nft_regs *regs,
		   const struct nft_pktinfo *pkt)
{
	const struct nft_fib *priv = nft_expr_priv(expr);
	const struct net_device *oif = NULL;
	u32 *dest = &regs->data[priv->dreg];
	struct flowi6 fl6 = {
		.flowi6_iif = LOOPBACK_IFINDEX,
		.flowi6_proto = pkt->tprot,
	};
	struct rt6_info *rt;
	int lookup_flags;

	if (priv->flags & NFTA_FIB_F_IIF)
		oif = nft_in(pkt);
	else if (priv->flags & NFTA_FIB_F_OIF)
		oif = nft_out(pkt);

	lookup_flags = nft_fib6_flowi_init(&fl6, priv, pkt, oif);

	if (nft_hook(pkt) == NF_INET_PRE_ROUTING &&
	    nft_fib_is_loopback(pkt->skb, nft_in(pkt))) {
		nft_fib_store_result(dest, priv->result, pkt,
				     nft_in(pkt)->ifindex);
		return;
	}

	*dest = 0;
 again:
	rt = (void *)ip6_route_lookup(nft_net(pkt), &fl6, lookup_flags);
	if (rt->dst.error)
		goto put_rt_err;

	/* Should not see RTF_LOCAL here */
	if (rt->rt6i_flags & (RTF_REJECT | RTF_ANYCAST | RTF_LOCAL))
		goto put_rt_err;

	if (oif && oif != rt->rt6i_idev->dev) {
		/* multipath route? Try again with F_IFACE */
		if ((lookup_flags & RT6_LOOKUP_F_IFACE) == 0) {
			lookup_flags |= RT6_LOOKUP_F_IFACE;
			fl6.flowi6_oif = oif->ifindex;
			ip6_rt_put(rt);
			goto again;
		}
	}

	switch (priv->result) {
	case NFT_FIB_RESULT_OIF:
		*dest = rt->rt6i_idev->dev->ifindex;
		break;
	case NFT_FIB_RESULT_OIFNAME:
		strncpy((char *)dest, rt->rt6i_idev->dev->name, IFNAMSIZ);
		break;
	default:
		WARN_ON_ONCE(1);
		break;
	}

 put_rt_err:
	ip6_rt_put(rt);
}
EXPORT_SYMBOL_GPL(nft_fib6_eval);

static struct nft_expr_type nft_fib6_type;

static const struct nft_expr_ops nft_fib6_type_ops = {
	.type		= &nft_fib6_type,
	.size		= NFT_EXPR_SIZE(sizeof(struct nft_fib)),
	.eval		= nft_fib6_eval_type,
	.init		= nft_fib_init,
	.dump		= nft_fib_dump,
	.validate	= nft_fib_validate,
};

static const struct nft_expr_ops nft_fib6_ops = {
	.type		= &nft_fib6_type,
	.size		= NFT_EXPR_SIZE(sizeof(struct nft_fib)),
	.eval		= nft_fib6_eval,
	.init		= nft_fib_init,
	.dump		= nft_fib_dump,
	.validate	= nft_fib_validate,
};

static const struct nft_expr_ops *
nft_fib6_select_ops(const struct nft_ctx *ctx,
		    const struct nlattr * const tb[])
{
	enum nft_fib_result result;

	if (!tb[NFTA_FIB_RESULT])
		return ERR_PTR(-EINVAL);

	result = ntohl(nla_get_be32(tb[NFTA_FIB_RESULT]));

	switch (result) {
	case NFT_FIB_RESULT_OIF:
		return &nft_fib6_ops;
	case NFT_FIB_RESULT_OIFNAME:
		return &nft_fib6_ops;
	case NFT_FIB_RESULT_ADDRTYPE:
		return &nft_fib6_type_ops;
	default:
		return ERR_PTR(-EOPNOTSUPP);
	}
}

static struct nft_expr_type nft_fib6_type __read_mostly = {
	.name		= "fib",
	.select_ops	= &nft_fib6_select_ops,
	.policy		= nft_fib_policy,
	.maxattr	= NFTA_FIB_MAX,
	.family		= NFPROTO_IPV6,
	.owner		= THIS_MODULE,
};

static int __init nft_fib6_module_init(void)
{
	return nft_register_expr(&nft_fib6_type);
}

static void __exit nft_fib6_module_exit(void)
{
	nft_unregister_expr(&nft_fib6_type);
}
module_init(nft_fib6_module_init);
module_exit(nft_fib6_module_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Florian Westphal <*****@*****.**>");
MODULE_ALIAS_NFT_AF_EXPR(10, "fib");
Example #2
0
void nft_fib4_eval(const struct nft_expr *expr, struct nft_regs *regs,
		   const struct nft_pktinfo *pkt)
{
	const struct nft_fib *priv = nft_expr_priv(expr);
	int noff = skb_network_offset(pkt->skb);
	u32 *dest = &regs->data[priv->dreg];
	struct iphdr *iph, _iph;
	struct fib_result res;
	struct flowi4 fl4 = {
		.flowi4_scope = RT_SCOPE_UNIVERSE,
		.flowi4_iif = LOOPBACK_IFINDEX,
	};
	const struct net_device *oif;
	struct net_device *found;
#ifdef CONFIG_IP_ROUTE_MULTIPATH
	int i;
#endif

	/*
	 * Do not set flowi4_oif, it restricts results (for example, asking
	 * for oif 3 will get RTN_UNICAST result even if the daddr exits
	 * on another interface.
	 *
	 * Search results for the desired outinterface instead.
	 */
	if (priv->flags & NFTA_FIB_F_OIF)
		oif = nft_out(pkt);
	else if (priv->flags & NFTA_FIB_F_IIF)
		oif = nft_in(pkt);
	else
		oif = NULL;

	if (nft_hook(pkt) == NF_INET_PRE_ROUTING &&
	    nft_fib_is_loopback(pkt->skb, nft_in(pkt))) {
		nft_fib_store_result(dest, priv, pkt,
				     nft_in(pkt)->ifindex);
		return;
	}

	iph = skb_header_pointer(pkt->skb, noff, sizeof(_iph), &_iph);
	if (!iph) {
		regs->verdict.code = NFT_BREAK;
		return;
	}

	if (ipv4_is_zeronet(iph->saddr)) {
		if (ipv4_is_lbcast(iph->daddr) ||
		    ipv4_is_local_multicast(iph->daddr)) {
			nft_fib_store_result(dest, priv, pkt,
					     get_ifindex(pkt->skb->dev));
			return;
		}
	}

	if (priv->flags & NFTA_FIB_F_MARK)
		fl4.flowi4_mark = pkt->skb->mark;

	fl4.flowi4_tos = iph->tos & DSCP_BITS;

	if (priv->flags & NFTA_FIB_F_DADDR) {
		fl4.daddr = iph->daddr;
		fl4.saddr = get_saddr(iph->saddr);
	} else {
		fl4.daddr = iph->saddr;
		fl4.saddr = get_saddr(iph->daddr);
	}

	*dest = 0;

	if (fib_lookup(nft_net(pkt), &fl4, &res, FIB_LOOKUP_IGNORE_LINKSTATE))
		return;

	switch (res.type) {
	case RTN_UNICAST:
		break;
	case RTN_LOCAL: /* Should not see RTN_LOCAL here */
		return;
	default:
		break;
	}

       if (!oif) {
               found = FIB_RES_DEV(res);
               goto ok;
       }

#ifdef CONFIG_IP_ROUTE_MULTIPATH
	for (i = 0; i < res.fi->fib_nhs; i++) {
		struct fib_nh *nh = &res.fi->fib_nh[i];

		if (nh->nh_dev == oif) {
			found = nh->nh_dev;
			goto ok;
		}
	}
	return;
#else
	found = FIB_RES_DEV(res);
	if (found != oif)
		return;
#endif
ok:
	switch (priv->result) {
	case NFT_FIB_RESULT_OIF:
		*dest = found->ifindex;
		break;
	case NFT_FIB_RESULT_OIFNAME:
		strncpy((char *)dest, found->name, IFNAMSIZ);
		break;
	default:
		WARN_ON_ONCE(1);
		break;
	}
}