Example #1
0
/*
 *	device anycast group inc (add if not found)
 */
int __ipv6_dev_ac_inc(struct inet6_dev *idev, const struct in6_addr *addr)
{
	struct ifacaddr6 *aca;
	struct rt6_info *rt;
	int err;

	ASSERT_RTNL();

	write_lock_bh(&idev->lock);
	if (idev->dead) {
		err = -ENODEV;
		goto out;
	}

	for (aca = idev->ac_list; aca; aca = aca->aca_next) {
		if (ipv6_addr_equal(&aca->aca_addr, addr)) {
			aca->aca_users++;
			err = 0;
			goto out;
		}
	}

	rt = addrconf_dst_alloc(idev, addr, true);
	if (IS_ERR(rt)) {
		err = PTR_ERR(rt);
		goto out;
	}
	aca = aca_alloc(rt, addr);
	if (!aca) {
		ip6_rt_put(rt);
		err = -ENOMEM;
		goto out;
	}

	aca->aca_next = idev->ac_list;
	idev->ac_list = aca;

	/* Hold this for addrconf_join_solict() below before we unlock,
	 * it is already exposed via idev->ac_list.
	 */
	aca_get(aca);
	write_unlock_bh(&idev->lock);

	ip6_ins_rt(rt);

	addrconf_join_solict(idev->dev, &aca->aca_addr);

	aca_put(aca);
	return 0;
out:
	write_unlock_bh(&idev->lock);
	return err;
}
Example #2
0
static bool rpfilter_lookup_reverse6(struct net *net, const struct sk_buff *skb,
                                     const struct net_device *dev, u8 flags)
{
    struct rt6_info *rt;
    struct ipv6hdr *iph = ipv6_hdr(skb);
    bool ret = false;
    struct flowi6 fl6 = {
        .flowi6_iif = LOOPBACK_IFINDEX,
        .flowlabel = (* (__be32 *) iph) & IPV6_FLOWINFO_MASK,
        .flowi6_proto = iph->nexthdr,
        .daddr = iph->saddr,
    };
    int lookup_flags;

    if (rpfilter_addr_unicast(&iph->daddr)) {
        memcpy(&fl6.saddr, &iph->daddr, sizeof(struct in6_addr));
        lookup_flags = RT6_LOOKUP_F_HAS_SADDR;
    } else {
        lookup_flags = 0;
    }

    fl6.flowi6_mark = flags & XT_RPFILTER_VALID_MARK ? skb->mark : 0;
    if ((flags & XT_RPFILTER_LOOSE) == 0) {
        fl6.flowi6_oif = dev->ifindex;
        lookup_flags |= RT6_LOOKUP_F_IFACE;
    }

    rt = (void *) ip6_route_lookup(net, &fl6, lookup_flags);
    if (rt->dst.error)
        goto out;

    if (rt->rt6i_flags & (RTF_REJECT|RTF_ANYCAST))
        goto out;

    if (rt->rt6i_flags & RTF_LOCAL) {
        ret = flags & XT_RPFILTER_ACCEPT_LOCAL;
        goto out;
    }

    if (rt->rt6i_idev->dev == dev || (flags & XT_RPFILTER_LOOSE))
        ret = true;
out:
    ip6_rt_put(rt);
    return ret;
}

static bool rpfilter_is_local(const struct sk_buff *skb)
{
    const struct rt6_info *rt = (const void *) skb_dst(skb);
    return rt && (rt->rt6i_flags & RTF_LOCAL);
}

static bool rpfilter_mt(const struct sk_buff *skb, struct xt_action_param *par)
{
    const struct xt_rpfilter_info *info = par->matchinfo;
    int saddrtype;
    struct ipv6hdr *iph;
    bool invert = info->flags & XT_RPFILTER_INVERT;

    if (rpfilter_is_local(skb))
        return true ^ invert;

    iph = ipv6_hdr(skb);
    saddrtype = ipv6_addr_type(&iph->saddr);
    if (unlikely(saddrtype == IPV6_ADDR_ANY))
        return true ^ invert; /* not routable: forward path will drop it */

    return rpfilter_lookup_reverse6(par->net, skb, par->in, info->flags) ^ invert;
}

static int rpfilter_check(const struct xt_mtchk_param *par)
{
    const struct xt_rpfilter_info *info = par->matchinfo;
    unsigned int options = ~XT_RPFILTER_OPTION_MASK;

    if (info->flags & options) {
        pr_info("unknown options encountered");
        return -EINVAL;
    }

    if (strcmp(par->table, "mangle") != 0 &&
            strcmp(par->table, "raw") != 0) {
        pr_info("match only valid in the \'raw\' "
                "or \'mangle\' tables, not \'%s\'.\n", par->table);
        return -EINVAL;
    }

    return 0;
}

static struct xt_match rpfilter_mt_reg __read_mostly = {
    .name		= "rpfilter",
    .family		= NFPROTO_IPV6,
    .checkentry	= rpfilter_check,
    .match		= rpfilter_mt,
    .matchsize	= sizeof(struct xt_rpfilter_info),
    .hooks		= (1 << NF_INET_PRE_ROUTING),
    .me		= THIS_MODULE
};

static int __init rpfilter_mt_init(void)
{
    return xt_register_match(&rpfilter_mt_reg);
}

static void __exit rpfilter_mt_exit(void)
{
    xt_unregister_match(&rpfilter_mt_reg);
}

module_init(rpfilter_mt_init);
module_exit(rpfilter_mt_exit);
Example #3
0
int ip6_fragment(struct net *net, struct sock *sk, struct sk_buff *skb,
		 int (*output)(struct net *, struct sock *, struct sk_buff *))
{
	struct sk_buff *frag;
	struct rt6_info *rt = (struct rt6_info *)skb_dst(skb);
	struct ipv6_pinfo *np = skb->sk && !dev_recursion_level() ?
				inet6_sk(skb->sk) : NULL;
	struct ipv6hdr *tmp_hdr;
	struct frag_hdr *fh;
	unsigned int mtu, hlen, left, len;
	int hroom, troom;
	__be32 frag_id;
	int ptr, offset = 0, err = 0;
	u8 *prevhdr, nexthdr = 0;

	hlen = ip6_find_1stfragopt(skb, &prevhdr);
	nexthdr = *prevhdr;

	mtu = ip6_skb_dst_mtu(skb);

	/* We must not fragment if the socket is set to force MTU discovery
	 * or if the skb it not generated by a local socket.
	 */
	if (unlikely(!skb->ignore_df && skb->len > mtu))
		goto fail_toobig;

	if (IP6CB(skb)->frag_max_size) {
		if (IP6CB(skb)->frag_max_size > mtu)
			goto fail_toobig;

		/* don't send fragments larger than what we received */
		mtu = IP6CB(skb)->frag_max_size;
		if (mtu < IPV6_MIN_MTU)
			mtu = IPV6_MIN_MTU;
	}

	if (np && np->frag_size < mtu) {
		if (np->frag_size)
			mtu = np->frag_size;
	}
	if (mtu < hlen + sizeof(struct frag_hdr) + 8)
		goto fail_toobig;
	mtu -= hlen + sizeof(struct frag_hdr);

	frag_id = ipv6_select_ident(net, &ipv6_hdr(skb)->daddr,
				    &ipv6_hdr(skb)->saddr);

	if (skb->ip_summed == CHECKSUM_PARTIAL &&
	    (err = skb_checksum_help(skb)))
		goto fail;

	hroom = LL_RESERVED_SPACE(rt->dst.dev);
	if (skb_has_frag_list(skb)) {
		int first_len = skb_pagelen(skb);
		struct sk_buff *frag2;

		if (first_len - hlen > mtu ||
		    ((first_len - hlen) & 7) ||
		    skb_cloned(skb) ||
		    skb_headroom(skb) < (hroom + sizeof(struct frag_hdr)))
			goto slow_path;

		skb_walk_frags(skb, frag) {
			/* Correct geometry. */
			if (frag->len > mtu ||
			    ((frag->len & 7) && frag->next) ||
			    skb_headroom(frag) < (hlen + hroom + sizeof(struct frag_hdr)))
				goto slow_path_clean;

			/* Partially cloned skb? */
			if (skb_shared(frag))
				goto slow_path_clean;

			BUG_ON(frag->sk);
			if (skb->sk) {
				frag->sk = skb->sk;
				frag->destructor = sock_wfree;
			}
			skb->truesize -= frag->truesize;
		}

		err = 0;
		offset = 0;
		/* BUILD HEADER */

		*prevhdr = NEXTHDR_FRAGMENT;
		tmp_hdr = kmemdup(skb_network_header(skb), hlen, GFP_ATOMIC);
		if (!tmp_hdr) {
			IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
				      IPSTATS_MIB_FRAGFAILS);
			err = -ENOMEM;
			goto fail;
		}
		frag = skb_shinfo(skb)->frag_list;
		skb_frag_list_init(skb);

		__skb_pull(skb, hlen);
		fh = (struct frag_hdr *)__skb_push(skb, sizeof(struct frag_hdr));
		__skb_push(skb, hlen);
		skb_reset_network_header(skb);
		memcpy(skb_network_header(skb), tmp_hdr, hlen);

		fh->nexthdr = nexthdr;
		fh->reserved = 0;
		fh->frag_off = htons(IP6_MF);
		fh->identification = frag_id;

		first_len = skb_pagelen(skb);
		skb->data_len = first_len - skb_headlen(skb);
		skb->len = first_len;
		ipv6_hdr(skb)->payload_len = htons(first_len -
						   sizeof(struct ipv6hdr));

		dst_hold(&rt->dst);

		for (;;) {
			/* Prepare header of the next frame,
			 * before previous one went down. */
			if (frag) {
				frag->ip_summed = CHECKSUM_NONE;
				skb_reset_transport_header(frag);
				fh = (struct frag_hdr *)__skb_push(frag, sizeof(struct frag_hdr));
				__skb_push(frag, hlen);
				skb_reset_network_header(frag);
				memcpy(skb_network_header(frag), tmp_hdr,
				       hlen);
				offset += skb->len - hlen - sizeof(struct frag_hdr);
				fh->nexthdr = nexthdr;
				fh->reserved = 0;
				fh->frag_off = htons(offset);
				if (frag->next)
					fh->frag_off |= htons(IP6_MF);
				fh->identification = frag_id;
				ipv6_hdr(frag)->payload_len =
						htons(frag->len -
						      sizeof(struct ipv6hdr));
				ip6_copy_metadata(frag, skb);
			}

			err = output(net, sk, skb);
			if (!err)
				IP6_INC_STATS(net, ip6_dst_idev(&rt->dst),
					      IPSTATS_MIB_FRAGCREATES);

			if (err || !frag)
				break;

			skb = frag;
			frag = skb->next;
			skb->next = NULL;
		}

		kfree(tmp_hdr);

		if (err == 0) {
			IP6_INC_STATS(net, ip6_dst_idev(&rt->dst),
				      IPSTATS_MIB_FRAGOKS);
			ip6_rt_put(rt);
			return 0;
		}

		kfree_skb_list(frag);

		IP6_INC_STATS(net, ip6_dst_idev(&rt->dst),
			      IPSTATS_MIB_FRAGFAILS);
		ip6_rt_put(rt);
		return err;

slow_path_clean:
		skb_walk_frags(skb, frag2) {
			if (frag2 == frag)
				break;
			frag2->sk = NULL;
			frag2->destructor = NULL;
			skb->truesize += frag2->truesize;
		}
	}

slow_path:
	left = skb->len - hlen;		/* Space per frame */
	ptr = hlen;			/* Where to start from */

	/*
	 *	Fragment the datagram.
	 */

	*prevhdr = NEXTHDR_FRAGMENT;
	troom = rt->dst.dev->needed_tailroom;

	/*
	 *	Keep copying data until we run out.
	 */
	while (left > 0)	{
		len = left;
		/* IF: it doesn't fit, use 'mtu' - the data space left */
		if (len > mtu)
			len = mtu;
		/* IF: we are not sending up to and including the packet end
		   then align the next start on an eight byte boundary */
		if (len < left)	{
			len &= ~7;
		}

		/* Allocate buffer */
		frag = alloc_skb(len + hlen + sizeof(struct frag_hdr) +
				 hroom + troom, GFP_ATOMIC);
		if (!frag) {
			IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
				      IPSTATS_MIB_FRAGFAILS);
			err = -ENOMEM;
			goto fail;
		}

		/*
		 *	Set up data on packet
		 */

		ip6_copy_metadata(frag, skb);
		skb_reserve(frag, hroom);
		skb_put(frag, len + hlen + sizeof(struct frag_hdr));
		skb_reset_network_header(frag);
		fh = (struct frag_hdr *)(skb_network_header(frag) + hlen);
		frag->transport_header = (frag->network_header + hlen +
					  sizeof(struct frag_hdr));

		/*
		 *	Charge the memory for the fragment to any owner
		 *	it might possess
		 */
		if (skb->sk)
			skb_set_owner_w(frag, skb->sk);

		/*
		 *	Copy the packet header into the new buffer.
		 */
		skb_copy_from_linear_data(skb, skb_network_header(frag), hlen);

		/*
		 *	Build fragment header.
		 */
		fh->nexthdr = nexthdr;
		fh->reserved = 0;
		fh->identification = frag_id;

		/*
		 *	Copy a block of the IP datagram.
		 */
		BUG_ON(skb_copy_bits(skb, ptr, skb_transport_header(frag),
				     len));
		left -= len;

		fh->frag_off = htons(offset);
		if (left > 0)
			fh->frag_off |= htons(IP6_MF);
		ipv6_hdr(frag)->payload_len = htons(frag->len -
						    sizeof(struct ipv6hdr));

		ptr += len;
		offset += len;

		/*
		 *	Put this fragment into the sending queue.
		 */
		err = output(net, sk, frag);
		if (err)
			goto fail;

		IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
			      IPSTATS_MIB_FRAGCREATES);
	}
	IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
		      IPSTATS_MIB_FRAGOKS);
	consume_skb(skb);
	return err;

fail_toobig:
	if (skb->sk && dst_allfrag(skb_dst(skb)))
		sk_nocaps_add(skb->sk, NETIF_F_GSO_MASK);

	skb->dev = skb_dst(skb)->dev;
	icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
	err = -EMSGSIZE;

fail:
	IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
		      IPSTATS_MIB_FRAGFAILS);
	kfree_skb(skb);
	return err;
}
Example #4
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 #5
0
int ipv6_sock_ac_join(struct sock *sk, int ifindex, const struct in6_addr *addr)
{
	struct ipv6_pinfo *np = inet6_sk(sk);
	struct net_device *dev = NULL;
	struct inet6_dev *idev;
	struct ipv6_ac_socklist *pac;
	struct net *net = sock_net(sk);
	int	ishost = !net->ipv6.devconf_all->forwarding;
	int	err = 0;

	ASSERT_RTNL();

	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
		return -EPERM;
	if (ipv6_addr_is_multicast(addr))
		return -EINVAL;
	if (ipv6_chk_addr(net, addr, NULL, 0))
		return -EINVAL;

	pac = sock_kmalloc(sk, sizeof(struct ipv6_ac_socklist), GFP_KERNEL);
	if (!pac)
		return -ENOMEM;
	pac->acl_next = NULL;
	pac->acl_addr = *addr;

	if (ifindex == 0) {
		struct rt6_info *rt;

		rt = rt6_lookup(net, addr, NULL, 0, 0);
		if (rt) {
			dev = rt->dst.dev;
			ip6_rt_put(rt);
		} else if (ishost) {
			err = -EADDRNOTAVAIL;
			goto error;
		} else {
			/* router, no matching interface: just pick one */
			dev = __dev_get_by_flags(net, IFF_UP,
						 IFF_UP | IFF_LOOPBACK);
		}
	} else
		dev = __dev_get_by_index(net, ifindex);

	if (!dev) {
		err = -ENODEV;
		goto error;
	}

	idev = __in6_dev_get(dev);
	if (!idev) {
		if (ifindex)
			err = -ENODEV;
		else
			err = -EADDRNOTAVAIL;
		goto error;
	}
	/* reset ishost, now that we have a specific device */
	ishost = !idev->cnf.forwarding;

	pac->acl_ifindex = dev->ifindex;

	/* XXX
	 * For hosts, allow link-local or matching prefix anycasts.
	 * This obviates the need for propagating anycast routes while
	 * still allowing some non-router anycast participation.
	 */
	if (!ipv6_chk_prefix(addr, dev)) {
		if (ishost)
			err = -EADDRNOTAVAIL;
		if (err)
			goto error;
	}

	err = __ipv6_dev_ac_inc(idev, addr);
	if (!err) {
		pac->acl_next = np->ipv6_ac_list;
		np->ipv6_ac_list = pac;
		pac = NULL;
	}

error:
	if (pac)
		sock_kfree_s(sk, pac, sizeof(*pac));
	return err;
}