![Eric Dumazet](/assets/img/avatar_default.png)
Instead of testing defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
1755 lines
42 KiB
C
1755 lines
42 KiB
C
/*
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* Linux NET3: GRE over IP protocol decoder.
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*
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* Authors: Alexey Kuznetsov (kuznet@ms2.inr.ac.ru)
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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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* as published by the Free Software Foundation; either version
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* 2 of the License, or (at your option) any later version.
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*
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*/
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#include <linux/capability.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/slab.h>
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#include <asm/uaccess.h>
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#include <linux/skbuff.h>
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#include <linux/netdevice.h>
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#include <linux/in.h>
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#include <linux/tcp.h>
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#include <linux/udp.h>
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#include <linux/if_arp.h>
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#include <linux/mroute.h>
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#include <linux/init.h>
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#include <linux/in6.h>
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#include <linux/inetdevice.h>
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#include <linux/igmp.h>
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#include <linux/netfilter_ipv4.h>
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#include <linux/etherdevice.h>
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#include <linux/if_ether.h>
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#include <net/sock.h>
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#include <net/ip.h>
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#include <net/icmp.h>
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#include <net/protocol.h>
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#include <net/ipip.h>
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#include <net/arp.h>
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#include <net/checksum.h>
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#include <net/dsfield.h>
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#include <net/inet_ecn.h>
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#include <net/xfrm.h>
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#include <net/net_namespace.h>
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#include <net/netns/generic.h>
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#include <net/rtnetlink.h>
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#include <net/gre.h>
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#if IS_ENABLED(CONFIG_IPV6)
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#include <net/ipv6.h>
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#include <net/ip6_fib.h>
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#include <net/ip6_route.h>
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#endif
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/*
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Problems & solutions
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--------------------
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1. The most important issue is detecting local dead loops.
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They would cause complete host lockup in transmit, which
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would be "resolved" by stack overflow or, if queueing is enabled,
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with infinite looping in net_bh.
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We cannot track such dead loops during route installation,
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it is infeasible task. The most general solutions would be
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to keep skb->encapsulation counter (sort of local ttl),
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and silently drop packet when it expires. It is a good
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solution, but it supposes maintaing new variable in ALL
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skb, even if no tunneling is used.
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Current solution: xmit_recursion breaks dead loops. This is a percpu
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counter, since when we enter the first ndo_xmit(), cpu migration is
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forbidden. We force an exit if this counter reaches RECURSION_LIMIT
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2. Networking dead loops would not kill routers, but would really
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kill network. IP hop limit plays role of "t->recursion" in this case,
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if we copy it from packet being encapsulated to upper header.
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It is very good solution, but it introduces two problems:
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- Routing protocols, using packets with ttl=1 (OSPF, RIP2),
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do not work over tunnels.
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- traceroute does not work. I planned to relay ICMP from tunnel,
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so that this problem would be solved and traceroute output
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would even more informative. This idea appeared to be wrong:
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only Linux complies to rfc1812 now (yes, guys, Linux is the only
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true router now :-)), all routers (at least, in neighbourhood of mine)
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return only 8 bytes of payload. It is the end.
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Hence, if we want that OSPF worked or traceroute said something reasonable,
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we should search for another solution.
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One of them is to parse packet trying to detect inner encapsulation
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made by our node. It is difficult or even impossible, especially,
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taking into account fragmentation. TO be short, tt is not solution at all.
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Current solution: The solution was UNEXPECTEDLY SIMPLE.
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We force DF flag on tunnels with preconfigured hop limit,
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that is ALL. :-) Well, it does not remove the problem completely,
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but exponential growth of network traffic is changed to linear
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(branches, that exceed pmtu are pruned) and tunnel mtu
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fastly degrades to value <68, where looping stops.
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Yes, it is not good if there exists a router in the loop,
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which does not force DF, even when encapsulating packets have DF set.
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But it is not our problem! Nobody could accuse us, we made
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all that we could make. Even if it is your gated who injected
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fatal route to network, even if it were you who configured
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fatal static route: you are innocent. :-)
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3. Really, ipv4/ipip.c, ipv4/ip_gre.c and ipv6/sit.c contain
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practically identical code. It would be good to glue them
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together, but it is not very evident, how to make them modular.
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sit is integral part of IPv6, ipip and gre are naturally modular.
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We could extract common parts (hash table, ioctl etc)
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to a separate module (ip_tunnel.c).
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Alexey Kuznetsov.
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*/
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static struct rtnl_link_ops ipgre_link_ops __read_mostly;
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static int ipgre_tunnel_init(struct net_device *dev);
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static void ipgre_tunnel_setup(struct net_device *dev);
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static int ipgre_tunnel_bind_dev(struct net_device *dev);
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/* Fallback tunnel: no source, no destination, no key, no options */
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#define HASH_SIZE 16
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static int ipgre_net_id __read_mostly;
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struct ipgre_net {
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struct ip_tunnel __rcu *tunnels[4][HASH_SIZE];
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struct net_device *fb_tunnel_dev;
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};
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/* Tunnel hash table */
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/*
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4 hash tables:
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3: (remote,local)
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2: (remote,*)
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1: (*,local)
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0: (*,*)
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We require exact key match i.e. if a key is present in packet
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it will match only tunnel with the same key; if it is not present,
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it will match only keyless tunnel.
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All keysless packets, if not matched configured keyless tunnels
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will match fallback tunnel.
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*/
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#define HASH(addr) (((__force u32)addr^((__force u32)addr>>4))&0xF)
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#define tunnels_r_l tunnels[3]
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#define tunnels_r tunnels[2]
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#define tunnels_l tunnels[1]
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#define tunnels_wc tunnels[0]
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/*
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* Locking : hash tables are protected by RCU and RTNL
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*/
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#define for_each_ip_tunnel_rcu(start) \
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for (t = rcu_dereference(start); t; t = rcu_dereference(t->next))
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/* often modified stats are per cpu, other are shared (netdev->stats) */
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struct pcpu_tstats {
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unsigned long rx_packets;
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unsigned long rx_bytes;
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unsigned long tx_packets;
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unsigned long tx_bytes;
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} __attribute__((aligned(4*sizeof(unsigned long))));
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static struct net_device_stats *ipgre_get_stats(struct net_device *dev)
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{
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struct pcpu_tstats sum = { 0 };
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int i;
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for_each_possible_cpu(i) {
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const struct pcpu_tstats *tstats = per_cpu_ptr(dev->tstats, i);
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sum.rx_packets += tstats->rx_packets;
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sum.rx_bytes += tstats->rx_bytes;
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sum.tx_packets += tstats->tx_packets;
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sum.tx_bytes += tstats->tx_bytes;
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}
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dev->stats.rx_packets = sum.rx_packets;
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dev->stats.rx_bytes = sum.rx_bytes;
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dev->stats.tx_packets = sum.tx_packets;
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dev->stats.tx_bytes = sum.tx_bytes;
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return &dev->stats;
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}
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/* Given src, dst and key, find appropriate for input tunnel. */
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static struct ip_tunnel * ipgre_tunnel_lookup(struct net_device *dev,
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__be32 remote, __be32 local,
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__be32 key, __be16 gre_proto)
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{
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struct net *net = dev_net(dev);
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int link = dev->ifindex;
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unsigned int h0 = HASH(remote);
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unsigned int h1 = HASH(key);
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struct ip_tunnel *t, *cand = NULL;
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struct ipgre_net *ign = net_generic(net, ipgre_net_id);
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int dev_type = (gre_proto == htons(ETH_P_TEB)) ?
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ARPHRD_ETHER : ARPHRD_IPGRE;
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int score, cand_score = 4;
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for_each_ip_tunnel_rcu(ign->tunnels_r_l[h0 ^ h1]) {
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if (local != t->parms.iph.saddr ||
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remote != t->parms.iph.daddr ||
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key != t->parms.i_key ||
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!(t->dev->flags & IFF_UP))
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continue;
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if (t->dev->type != ARPHRD_IPGRE &&
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t->dev->type != dev_type)
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continue;
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score = 0;
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if (t->parms.link != link)
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score |= 1;
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if (t->dev->type != dev_type)
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score |= 2;
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if (score == 0)
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return t;
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if (score < cand_score) {
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cand = t;
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cand_score = score;
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}
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}
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for_each_ip_tunnel_rcu(ign->tunnels_r[h0 ^ h1]) {
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if (remote != t->parms.iph.daddr ||
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key != t->parms.i_key ||
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!(t->dev->flags & IFF_UP))
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continue;
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if (t->dev->type != ARPHRD_IPGRE &&
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t->dev->type != dev_type)
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continue;
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score = 0;
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if (t->parms.link != link)
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score |= 1;
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if (t->dev->type != dev_type)
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score |= 2;
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if (score == 0)
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return t;
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if (score < cand_score) {
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cand = t;
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cand_score = score;
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}
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}
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for_each_ip_tunnel_rcu(ign->tunnels_l[h1]) {
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if ((local != t->parms.iph.saddr &&
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(local != t->parms.iph.daddr ||
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!ipv4_is_multicast(local))) ||
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key != t->parms.i_key ||
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!(t->dev->flags & IFF_UP))
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continue;
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if (t->dev->type != ARPHRD_IPGRE &&
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t->dev->type != dev_type)
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continue;
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score = 0;
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if (t->parms.link != link)
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score |= 1;
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if (t->dev->type != dev_type)
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score |= 2;
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if (score == 0)
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return t;
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if (score < cand_score) {
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cand = t;
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cand_score = score;
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}
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}
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for_each_ip_tunnel_rcu(ign->tunnels_wc[h1]) {
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if (t->parms.i_key != key ||
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!(t->dev->flags & IFF_UP))
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continue;
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if (t->dev->type != ARPHRD_IPGRE &&
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t->dev->type != dev_type)
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continue;
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score = 0;
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if (t->parms.link != link)
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score |= 1;
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if (t->dev->type != dev_type)
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score |= 2;
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if (score == 0)
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return t;
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if (score < cand_score) {
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cand = t;
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cand_score = score;
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}
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}
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if (cand != NULL)
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return cand;
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dev = ign->fb_tunnel_dev;
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if (dev->flags & IFF_UP)
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return netdev_priv(dev);
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return NULL;
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}
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static struct ip_tunnel __rcu **__ipgre_bucket(struct ipgre_net *ign,
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struct ip_tunnel_parm *parms)
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{
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__be32 remote = parms->iph.daddr;
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__be32 local = parms->iph.saddr;
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__be32 key = parms->i_key;
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unsigned int h = HASH(key);
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int prio = 0;
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if (local)
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prio |= 1;
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if (remote && !ipv4_is_multicast(remote)) {
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prio |= 2;
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h ^= HASH(remote);
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}
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return &ign->tunnels[prio][h];
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}
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static inline struct ip_tunnel __rcu **ipgre_bucket(struct ipgre_net *ign,
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struct ip_tunnel *t)
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{
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return __ipgre_bucket(ign, &t->parms);
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}
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static void ipgre_tunnel_link(struct ipgre_net *ign, struct ip_tunnel *t)
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{
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struct ip_tunnel __rcu **tp = ipgre_bucket(ign, t);
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rcu_assign_pointer(t->next, rtnl_dereference(*tp));
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rcu_assign_pointer(*tp, t);
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}
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static void ipgre_tunnel_unlink(struct ipgre_net *ign, struct ip_tunnel *t)
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{
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struct ip_tunnel __rcu **tp;
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struct ip_tunnel *iter;
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for (tp = ipgre_bucket(ign, t);
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(iter = rtnl_dereference(*tp)) != NULL;
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tp = &iter->next) {
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if (t == iter) {
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rcu_assign_pointer(*tp, t->next);
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break;
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}
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}
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}
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static struct ip_tunnel *ipgre_tunnel_find(struct net *net,
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struct ip_tunnel_parm *parms,
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int type)
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{
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__be32 remote = parms->iph.daddr;
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__be32 local = parms->iph.saddr;
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__be32 key = parms->i_key;
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int link = parms->link;
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struct ip_tunnel *t;
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struct ip_tunnel __rcu **tp;
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struct ipgre_net *ign = net_generic(net, ipgre_net_id);
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for (tp = __ipgre_bucket(ign, parms);
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(t = rtnl_dereference(*tp)) != NULL;
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tp = &t->next)
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if (local == t->parms.iph.saddr &&
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remote == t->parms.iph.daddr &&
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key == t->parms.i_key &&
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link == t->parms.link &&
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type == t->dev->type)
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break;
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return t;
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}
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static struct ip_tunnel *ipgre_tunnel_locate(struct net *net,
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struct ip_tunnel_parm *parms, int create)
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{
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struct ip_tunnel *t, *nt;
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struct net_device *dev;
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char name[IFNAMSIZ];
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struct ipgre_net *ign = net_generic(net, ipgre_net_id);
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t = ipgre_tunnel_find(net, parms, ARPHRD_IPGRE);
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if (t || !create)
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return t;
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if (parms->name[0])
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strlcpy(name, parms->name, IFNAMSIZ);
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else
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strcpy(name, "gre%d");
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dev = alloc_netdev(sizeof(*t), name, ipgre_tunnel_setup);
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if (!dev)
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return NULL;
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dev_net_set(dev, net);
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nt = netdev_priv(dev);
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nt->parms = *parms;
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dev->rtnl_link_ops = &ipgre_link_ops;
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dev->mtu = ipgre_tunnel_bind_dev(dev);
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if (register_netdevice(dev) < 0)
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goto failed_free;
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dev_hold(dev);
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ipgre_tunnel_link(ign, nt);
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return nt;
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failed_free:
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free_netdev(dev);
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return NULL;
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}
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static void ipgre_tunnel_uninit(struct net_device *dev)
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{
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struct net *net = dev_net(dev);
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struct ipgre_net *ign = net_generic(net, ipgre_net_id);
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ipgre_tunnel_unlink(ign, netdev_priv(dev));
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dev_put(dev);
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}
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static void ipgre_err(struct sk_buff *skb, u32 info)
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{
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/* All the routers (except for Linux) return only
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8 bytes of packet payload. It means, that precise relaying of
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ICMP in the real Internet is absolutely infeasible.
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Moreover, Cisco "wise men" put GRE key to the third word
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in GRE header. It makes impossible maintaining even soft state for keyed
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GRE tunnels with enabled checksum. Tell them "thank you".
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Well, I wonder, rfc1812 was written by Cisco employee,
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what the hell these idiots break standrads established
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by themself???
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*/
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const struct iphdr *iph = (const struct iphdr *)skb->data;
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__be16 *p = (__be16*)(skb->data+(iph->ihl<<2));
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int grehlen = (iph->ihl<<2) + 4;
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const int type = icmp_hdr(skb)->type;
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const int code = icmp_hdr(skb)->code;
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struct ip_tunnel *t;
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__be16 flags;
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flags = p[0];
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if (flags&(GRE_CSUM|GRE_KEY|GRE_SEQ|GRE_ROUTING|GRE_VERSION)) {
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if (flags&(GRE_VERSION|GRE_ROUTING))
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return;
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if (flags&GRE_KEY) {
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grehlen += 4;
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if (flags&GRE_CSUM)
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grehlen += 4;
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}
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}
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/* If only 8 bytes returned, keyed message will be dropped here */
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if (skb_headlen(skb) < grehlen)
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return;
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switch (type) {
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default:
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case ICMP_PARAMETERPROB:
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return;
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case ICMP_DEST_UNREACH:
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switch (code) {
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case ICMP_SR_FAILED:
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case ICMP_PORT_UNREACH:
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/* Impossible event. */
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return;
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case ICMP_FRAG_NEEDED:
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/* Soft state for pmtu is maintained by IP core. */
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return;
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default:
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/* All others are translated to HOST_UNREACH.
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rfc2003 contains "deep thoughts" about NET_UNREACH,
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I believe they are just ether pollution. --ANK
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*/
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break;
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}
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break;
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case ICMP_TIME_EXCEEDED:
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if (code != ICMP_EXC_TTL)
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return;
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break;
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}
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rcu_read_lock();
|
|
t = ipgre_tunnel_lookup(skb->dev, iph->daddr, iph->saddr,
|
|
flags & GRE_KEY ?
|
|
*(((__be32 *)p) + (grehlen / 4) - 1) : 0,
|
|
p[1]);
|
|
if (t == NULL || t->parms.iph.daddr == 0 ||
|
|
ipv4_is_multicast(t->parms.iph.daddr))
|
|
goto out;
|
|
|
|
if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED)
|
|
goto out;
|
|
|
|
if (time_before(jiffies, t->err_time + IPTUNNEL_ERR_TIMEO))
|
|
t->err_count++;
|
|
else
|
|
t->err_count = 1;
|
|
t->err_time = jiffies;
|
|
out:
|
|
rcu_read_unlock();
|
|
}
|
|
|
|
static inline void ipgre_ecn_decapsulate(const struct iphdr *iph, struct sk_buff *skb)
|
|
{
|
|
if (INET_ECN_is_ce(iph->tos)) {
|
|
if (skb->protocol == htons(ETH_P_IP)) {
|
|
IP_ECN_set_ce(ip_hdr(skb));
|
|
} else if (skb->protocol == htons(ETH_P_IPV6)) {
|
|
IP6_ECN_set_ce(ipv6_hdr(skb));
|
|
}
|
|
}
|
|
}
|
|
|
|
static inline u8
|
|
ipgre_ecn_encapsulate(u8 tos, const struct iphdr *old_iph, struct sk_buff *skb)
|
|
{
|
|
u8 inner = 0;
|
|
if (skb->protocol == htons(ETH_P_IP))
|
|
inner = old_iph->tos;
|
|
else if (skb->protocol == htons(ETH_P_IPV6))
|
|
inner = ipv6_get_dsfield((const struct ipv6hdr *)old_iph);
|
|
return INET_ECN_encapsulate(tos, inner);
|
|
}
|
|
|
|
static int ipgre_rcv(struct sk_buff *skb)
|
|
{
|
|
const struct iphdr *iph;
|
|
u8 *h;
|
|
__be16 flags;
|
|
__sum16 csum = 0;
|
|
__be32 key = 0;
|
|
u32 seqno = 0;
|
|
struct ip_tunnel *tunnel;
|
|
int offset = 4;
|
|
__be16 gre_proto;
|
|
|
|
if (!pskb_may_pull(skb, 16))
|
|
goto drop_nolock;
|
|
|
|
iph = ip_hdr(skb);
|
|
h = skb->data;
|
|
flags = *(__be16*)h;
|
|
|
|
if (flags&(GRE_CSUM|GRE_KEY|GRE_ROUTING|GRE_SEQ|GRE_VERSION)) {
|
|
/* - Version must be 0.
|
|
- We do not support routing headers.
|
|
*/
|
|
if (flags&(GRE_VERSION|GRE_ROUTING))
|
|
goto drop_nolock;
|
|
|
|
if (flags&GRE_CSUM) {
|
|
switch (skb->ip_summed) {
|
|
case CHECKSUM_COMPLETE:
|
|
csum = csum_fold(skb->csum);
|
|
if (!csum)
|
|
break;
|
|
/* fall through */
|
|
case CHECKSUM_NONE:
|
|
skb->csum = 0;
|
|
csum = __skb_checksum_complete(skb);
|
|
skb->ip_summed = CHECKSUM_COMPLETE;
|
|
}
|
|
offset += 4;
|
|
}
|
|
if (flags&GRE_KEY) {
|
|
key = *(__be32*)(h + offset);
|
|
offset += 4;
|
|
}
|
|
if (flags&GRE_SEQ) {
|
|
seqno = ntohl(*(__be32*)(h + offset));
|
|
offset += 4;
|
|
}
|
|
}
|
|
|
|
gre_proto = *(__be16 *)(h + 2);
|
|
|
|
rcu_read_lock();
|
|
if ((tunnel = ipgre_tunnel_lookup(skb->dev,
|
|
iph->saddr, iph->daddr, key,
|
|
gre_proto))) {
|
|
struct pcpu_tstats *tstats;
|
|
|
|
secpath_reset(skb);
|
|
|
|
skb->protocol = gre_proto;
|
|
/* WCCP version 1 and 2 protocol decoding.
|
|
* - Change protocol to IP
|
|
* - When dealing with WCCPv2, Skip extra 4 bytes in GRE header
|
|
*/
|
|
if (flags == 0 && gre_proto == htons(ETH_P_WCCP)) {
|
|
skb->protocol = htons(ETH_P_IP);
|
|
if ((*(h + offset) & 0xF0) != 0x40)
|
|
offset += 4;
|
|
}
|
|
|
|
skb->mac_header = skb->network_header;
|
|
__pskb_pull(skb, offset);
|
|
skb_postpull_rcsum(skb, skb_transport_header(skb), offset);
|
|
skb->pkt_type = PACKET_HOST;
|
|
#ifdef CONFIG_NET_IPGRE_BROADCAST
|
|
if (ipv4_is_multicast(iph->daddr)) {
|
|
/* Looped back packet, drop it! */
|
|
if (rt_is_output_route(skb_rtable(skb)))
|
|
goto drop;
|
|
tunnel->dev->stats.multicast++;
|
|
skb->pkt_type = PACKET_BROADCAST;
|
|
}
|
|
#endif
|
|
|
|
if (((flags&GRE_CSUM) && csum) ||
|
|
(!(flags&GRE_CSUM) && tunnel->parms.i_flags&GRE_CSUM)) {
|
|
tunnel->dev->stats.rx_crc_errors++;
|
|
tunnel->dev->stats.rx_errors++;
|
|
goto drop;
|
|
}
|
|
if (tunnel->parms.i_flags&GRE_SEQ) {
|
|
if (!(flags&GRE_SEQ) ||
|
|
(tunnel->i_seqno && (s32)(seqno - tunnel->i_seqno) < 0)) {
|
|
tunnel->dev->stats.rx_fifo_errors++;
|
|
tunnel->dev->stats.rx_errors++;
|
|
goto drop;
|
|
}
|
|
tunnel->i_seqno = seqno + 1;
|
|
}
|
|
|
|
/* Warning: All skb pointers will be invalidated! */
|
|
if (tunnel->dev->type == ARPHRD_ETHER) {
|
|
if (!pskb_may_pull(skb, ETH_HLEN)) {
|
|
tunnel->dev->stats.rx_length_errors++;
|
|
tunnel->dev->stats.rx_errors++;
|
|
goto drop;
|
|
}
|
|
|
|
iph = ip_hdr(skb);
|
|
skb->protocol = eth_type_trans(skb, tunnel->dev);
|
|
skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN);
|
|
}
|
|
|
|
tstats = this_cpu_ptr(tunnel->dev->tstats);
|
|
tstats->rx_packets++;
|
|
tstats->rx_bytes += skb->len;
|
|
|
|
__skb_tunnel_rx(skb, tunnel->dev);
|
|
|
|
skb_reset_network_header(skb);
|
|
ipgre_ecn_decapsulate(iph, skb);
|
|
|
|
netif_rx(skb);
|
|
|
|
rcu_read_unlock();
|
|
return 0;
|
|
}
|
|
icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0);
|
|
|
|
drop:
|
|
rcu_read_unlock();
|
|
drop_nolock:
|
|
kfree_skb(skb);
|
|
return 0;
|
|
}
|
|
|
|
static netdev_tx_t ipgre_tunnel_xmit(struct sk_buff *skb, struct net_device *dev)
|
|
{
|
|
struct ip_tunnel *tunnel = netdev_priv(dev);
|
|
struct pcpu_tstats *tstats;
|
|
const struct iphdr *old_iph = ip_hdr(skb);
|
|
const struct iphdr *tiph;
|
|
struct flowi4 fl4;
|
|
u8 tos;
|
|
__be16 df;
|
|
struct rtable *rt; /* Route to the other host */
|
|
struct net_device *tdev; /* Device to other host */
|
|
struct iphdr *iph; /* Our new IP header */
|
|
unsigned int max_headroom; /* The extra header space needed */
|
|
int gre_hlen;
|
|
__be32 dst;
|
|
int mtu;
|
|
|
|
if (dev->type == ARPHRD_ETHER)
|
|
IPCB(skb)->flags = 0;
|
|
|
|
if (dev->header_ops && dev->type == ARPHRD_IPGRE) {
|
|
gre_hlen = 0;
|
|
tiph = (const struct iphdr *)skb->data;
|
|
} else {
|
|
gre_hlen = tunnel->hlen;
|
|
tiph = &tunnel->parms.iph;
|
|
}
|
|
|
|
if ((dst = tiph->daddr) == 0) {
|
|
/* NBMA tunnel */
|
|
|
|
if (skb_dst(skb) == NULL) {
|
|
dev->stats.tx_fifo_errors++;
|
|
goto tx_error;
|
|
}
|
|
|
|
if (skb->protocol == htons(ETH_P_IP)) {
|
|
rt = skb_rtable(skb);
|
|
if ((dst = rt->rt_gateway) == 0)
|
|
goto tx_error_icmp;
|
|
}
|
|
#if IS_ENABLED(CONFIG_IPV6)
|
|
else if (skb->protocol == htons(ETH_P_IPV6)) {
|
|
struct neighbour *neigh = dst_get_neighbour_noref(skb_dst(skb));
|
|
const struct in6_addr *addr6;
|
|
int addr_type;
|
|
|
|
if (neigh == NULL)
|
|
goto tx_error;
|
|
|
|
addr6 = (const struct in6_addr *)&neigh->primary_key;
|
|
addr_type = ipv6_addr_type(addr6);
|
|
|
|
if (addr_type == IPV6_ADDR_ANY) {
|
|
addr6 = &ipv6_hdr(skb)->daddr;
|
|
addr_type = ipv6_addr_type(addr6);
|
|
}
|
|
|
|
if ((addr_type & IPV6_ADDR_COMPATv4) == 0)
|
|
goto tx_error_icmp;
|
|
|
|
dst = addr6->s6_addr32[3];
|
|
}
|
|
#endif
|
|
else
|
|
goto tx_error;
|
|
}
|
|
|
|
tos = tiph->tos;
|
|
if (tos == 1) {
|
|
tos = 0;
|
|
if (skb->protocol == htons(ETH_P_IP))
|
|
tos = old_iph->tos;
|
|
else if (skb->protocol == htons(ETH_P_IPV6))
|
|
tos = ipv6_get_dsfield((const struct ipv6hdr *)old_iph);
|
|
}
|
|
|
|
rt = ip_route_output_gre(dev_net(dev), &fl4, dst, tiph->saddr,
|
|
tunnel->parms.o_key, RT_TOS(tos),
|
|
tunnel->parms.link);
|
|
if (IS_ERR(rt)) {
|
|
dev->stats.tx_carrier_errors++;
|
|
goto tx_error;
|
|
}
|
|
tdev = rt->dst.dev;
|
|
|
|
if (tdev == dev) {
|
|
ip_rt_put(rt);
|
|
dev->stats.collisions++;
|
|
goto tx_error;
|
|
}
|
|
|
|
df = tiph->frag_off;
|
|
if (df)
|
|
mtu = dst_mtu(&rt->dst) - dev->hard_header_len - tunnel->hlen;
|
|
else
|
|
mtu = skb_dst(skb) ? dst_mtu(skb_dst(skb)) : dev->mtu;
|
|
|
|
if (skb_dst(skb))
|
|
skb_dst(skb)->ops->update_pmtu(skb_dst(skb), mtu);
|
|
|
|
if (skb->protocol == htons(ETH_P_IP)) {
|
|
df |= (old_iph->frag_off&htons(IP_DF));
|
|
|
|
if ((old_iph->frag_off&htons(IP_DF)) &&
|
|
mtu < ntohs(old_iph->tot_len)) {
|
|
icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, htonl(mtu));
|
|
ip_rt_put(rt);
|
|
goto tx_error;
|
|
}
|
|
}
|
|
#if IS_ENABLED(CONFIG_IPV6)
|
|
else if (skb->protocol == htons(ETH_P_IPV6)) {
|
|
struct rt6_info *rt6 = (struct rt6_info *)skb_dst(skb);
|
|
|
|
if (rt6 && mtu < dst_mtu(skb_dst(skb)) && mtu >= IPV6_MIN_MTU) {
|
|
if ((tunnel->parms.iph.daddr &&
|
|
!ipv4_is_multicast(tunnel->parms.iph.daddr)) ||
|
|
rt6->rt6i_dst.plen == 128) {
|
|
rt6->rt6i_flags |= RTF_MODIFIED;
|
|
dst_metric_set(skb_dst(skb), RTAX_MTU, mtu);
|
|
}
|
|
}
|
|
|
|
if (mtu >= IPV6_MIN_MTU && mtu < skb->len - tunnel->hlen + gre_hlen) {
|
|
icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
|
|
ip_rt_put(rt);
|
|
goto tx_error;
|
|
}
|
|
}
|
|
#endif
|
|
|
|
if (tunnel->err_count > 0) {
|
|
if (time_before(jiffies,
|
|
tunnel->err_time + IPTUNNEL_ERR_TIMEO)) {
|
|
tunnel->err_count--;
|
|
|
|
dst_link_failure(skb);
|
|
} else
|
|
tunnel->err_count = 0;
|
|
}
|
|
|
|
max_headroom = LL_RESERVED_SPACE(tdev) + gre_hlen + rt->dst.header_len;
|
|
|
|
if (skb_headroom(skb) < max_headroom || skb_shared(skb)||
|
|
(skb_cloned(skb) && !skb_clone_writable(skb, 0))) {
|
|
struct sk_buff *new_skb = skb_realloc_headroom(skb, max_headroom);
|
|
if (max_headroom > dev->needed_headroom)
|
|
dev->needed_headroom = max_headroom;
|
|
if (!new_skb) {
|
|
ip_rt_put(rt);
|
|
dev->stats.tx_dropped++;
|
|
dev_kfree_skb(skb);
|
|
return NETDEV_TX_OK;
|
|
}
|
|
if (skb->sk)
|
|
skb_set_owner_w(new_skb, skb->sk);
|
|
dev_kfree_skb(skb);
|
|
skb = new_skb;
|
|
old_iph = ip_hdr(skb);
|
|
}
|
|
|
|
skb_reset_transport_header(skb);
|
|
skb_push(skb, gre_hlen);
|
|
skb_reset_network_header(skb);
|
|
memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
|
|
IPCB(skb)->flags &= ~(IPSKB_XFRM_TUNNEL_SIZE | IPSKB_XFRM_TRANSFORMED |
|
|
IPSKB_REROUTED);
|
|
skb_dst_drop(skb);
|
|
skb_dst_set(skb, &rt->dst);
|
|
|
|
/*
|
|
* Push down and install the IPIP header.
|
|
*/
|
|
|
|
iph = ip_hdr(skb);
|
|
iph->version = 4;
|
|
iph->ihl = sizeof(struct iphdr) >> 2;
|
|
iph->frag_off = df;
|
|
iph->protocol = IPPROTO_GRE;
|
|
iph->tos = ipgre_ecn_encapsulate(tos, old_iph, skb);
|
|
iph->daddr = fl4.daddr;
|
|
iph->saddr = fl4.saddr;
|
|
|
|
if ((iph->ttl = tiph->ttl) == 0) {
|
|
if (skb->protocol == htons(ETH_P_IP))
|
|
iph->ttl = old_iph->ttl;
|
|
#if IS_ENABLED(CONFIG_IPV6)
|
|
else if (skb->protocol == htons(ETH_P_IPV6))
|
|
iph->ttl = ((const struct ipv6hdr *)old_iph)->hop_limit;
|
|
#endif
|
|
else
|
|
iph->ttl = ip4_dst_hoplimit(&rt->dst);
|
|
}
|
|
|
|
((__be16 *)(iph + 1))[0] = tunnel->parms.o_flags;
|
|
((__be16 *)(iph + 1))[1] = (dev->type == ARPHRD_ETHER) ?
|
|
htons(ETH_P_TEB) : skb->protocol;
|
|
|
|
if (tunnel->parms.o_flags&(GRE_KEY|GRE_CSUM|GRE_SEQ)) {
|
|
__be32 *ptr = (__be32*)(((u8*)iph) + tunnel->hlen - 4);
|
|
|
|
if (tunnel->parms.o_flags&GRE_SEQ) {
|
|
++tunnel->o_seqno;
|
|
*ptr = htonl(tunnel->o_seqno);
|
|
ptr--;
|
|
}
|
|
if (tunnel->parms.o_flags&GRE_KEY) {
|
|
*ptr = tunnel->parms.o_key;
|
|
ptr--;
|
|
}
|
|
if (tunnel->parms.o_flags&GRE_CSUM) {
|
|
*ptr = 0;
|
|
*(__sum16*)ptr = ip_compute_csum((void*)(iph+1), skb->len - sizeof(struct iphdr));
|
|
}
|
|
}
|
|
|
|
nf_reset(skb);
|
|
tstats = this_cpu_ptr(dev->tstats);
|
|
__IPTUNNEL_XMIT(tstats, &dev->stats);
|
|
return NETDEV_TX_OK;
|
|
|
|
tx_error_icmp:
|
|
dst_link_failure(skb);
|
|
|
|
tx_error:
|
|
dev->stats.tx_errors++;
|
|
dev_kfree_skb(skb);
|
|
return NETDEV_TX_OK;
|
|
}
|
|
|
|
static int ipgre_tunnel_bind_dev(struct net_device *dev)
|
|
{
|
|
struct net_device *tdev = NULL;
|
|
struct ip_tunnel *tunnel;
|
|
const struct iphdr *iph;
|
|
int hlen = LL_MAX_HEADER;
|
|
int mtu = ETH_DATA_LEN;
|
|
int addend = sizeof(struct iphdr) + 4;
|
|
|
|
tunnel = netdev_priv(dev);
|
|
iph = &tunnel->parms.iph;
|
|
|
|
/* Guess output device to choose reasonable mtu and needed_headroom */
|
|
|
|
if (iph->daddr) {
|
|
struct flowi4 fl4;
|
|
struct rtable *rt;
|
|
|
|
rt = ip_route_output_gre(dev_net(dev), &fl4,
|
|
iph->daddr, iph->saddr,
|
|
tunnel->parms.o_key,
|
|
RT_TOS(iph->tos),
|
|
tunnel->parms.link);
|
|
if (!IS_ERR(rt)) {
|
|
tdev = rt->dst.dev;
|
|
ip_rt_put(rt);
|
|
}
|
|
|
|
if (dev->type != ARPHRD_ETHER)
|
|
dev->flags |= IFF_POINTOPOINT;
|
|
}
|
|
|
|
if (!tdev && tunnel->parms.link)
|
|
tdev = __dev_get_by_index(dev_net(dev), tunnel->parms.link);
|
|
|
|
if (tdev) {
|
|
hlen = tdev->hard_header_len + tdev->needed_headroom;
|
|
mtu = tdev->mtu;
|
|
}
|
|
dev->iflink = tunnel->parms.link;
|
|
|
|
/* Precalculate GRE options length */
|
|
if (tunnel->parms.o_flags&(GRE_CSUM|GRE_KEY|GRE_SEQ)) {
|
|
if (tunnel->parms.o_flags&GRE_CSUM)
|
|
addend += 4;
|
|
if (tunnel->parms.o_flags&GRE_KEY)
|
|
addend += 4;
|
|
if (tunnel->parms.o_flags&GRE_SEQ)
|
|
addend += 4;
|
|
}
|
|
dev->needed_headroom = addend + hlen;
|
|
mtu -= dev->hard_header_len + addend;
|
|
|
|
if (mtu < 68)
|
|
mtu = 68;
|
|
|
|
tunnel->hlen = addend;
|
|
|
|
return mtu;
|
|
}
|
|
|
|
static int
|
|
ipgre_tunnel_ioctl (struct net_device *dev, struct ifreq *ifr, int cmd)
|
|
{
|
|
int err = 0;
|
|
struct ip_tunnel_parm p;
|
|
struct ip_tunnel *t;
|
|
struct net *net = dev_net(dev);
|
|
struct ipgre_net *ign = net_generic(net, ipgre_net_id);
|
|
|
|
switch (cmd) {
|
|
case SIOCGETTUNNEL:
|
|
t = NULL;
|
|
if (dev == ign->fb_tunnel_dev) {
|
|
if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) {
|
|
err = -EFAULT;
|
|
break;
|
|
}
|
|
t = ipgre_tunnel_locate(net, &p, 0);
|
|
}
|
|
if (t == NULL)
|
|
t = netdev_priv(dev);
|
|
memcpy(&p, &t->parms, sizeof(p));
|
|
if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
|
|
err = -EFAULT;
|
|
break;
|
|
|
|
case SIOCADDTUNNEL:
|
|
case SIOCCHGTUNNEL:
|
|
err = -EPERM;
|
|
if (!capable(CAP_NET_ADMIN))
|
|
goto done;
|
|
|
|
err = -EFAULT;
|
|
if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
|
|
goto done;
|
|
|
|
err = -EINVAL;
|
|
if (p.iph.version != 4 || p.iph.protocol != IPPROTO_GRE ||
|
|
p.iph.ihl != 5 || (p.iph.frag_off&htons(~IP_DF)) ||
|
|
((p.i_flags|p.o_flags)&(GRE_VERSION|GRE_ROUTING)))
|
|
goto done;
|
|
if (p.iph.ttl)
|
|
p.iph.frag_off |= htons(IP_DF);
|
|
|
|
if (!(p.i_flags&GRE_KEY))
|
|
p.i_key = 0;
|
|
if (!(p.o_flags&GRE_KEY))
|
|
p.o_key = 0;
|
|
|
|
t = ipgre_tunnel_locate(net, &p, cmd == SIOCADDTUNNEL);
|
|
|
|
if (dev != ign->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
|
|
if (t != NULL) {
|
|
if (t->dev != dev) {
|
|
err = -EEXIST;
|
|
break;
|
|
}
|
|
} else {
|
|
unsigned int nflags = 0;
|
|
|
|
t = netdev_priv(dev);
|
|
|
|
if (ipv4_is_multicast(p.iph.daddr))
|
|
nflags = IFF_BROADCAST;
|
|
else if (p.iph.daddr)
|
|
nflags = IFF_POINTOPOINT;
|
|
|
|
if ((dev->flags^nflags)&(IFF_POINTOPOINT|IFF_BROADCAST)) {
|
|
err = -EINVAL;
|
|
break;
|
|
}
|
|
ipgre_tunnel_unlink(ign, t);
|
|
synchronize_net();
|
|
t->parms.iph.saddr = p.iph.saddr;
|
|
t->parms.iph.daddr = p.iph.daddr;
|
|
t->parms.i_key = p.i_key;
|
|
t->parms.o_key = p.o_key;
|
|
memcpy(dev->dev_addr, &p.iph.saddr, 4);
|
|
memcpy(dev->broadcast, &p.iph.daddr, 4);
|
|
ipgre_tunnel_link(ign, t);
|
|
netdev_state_change(dev);
|
|
}
|
|
}
|
|
|
|
if (t) {
|
|
err = 0;
|
|
if (cmd == SIOCCHGTUNNEL) {
|
|
t->parms.iph.ttl = p.iph.ttl;
|
|
t->parms.iph.tos = p.iph.tos;
|
|
t->parms.iph.frag_off = p.iph.frag_off;
|
|
if (t->parms.link != p.link) {
|
|
t->parms.link = p.link;
|
|
dev->mtu = ipgre_tunnel_bind_dev(dev);
|
|
netdev_state_change(dev);
|
|
}
|
|
}
|
|
if (copy_to_user(ifr->ifr_ifru.ifru_data, &t->parms, sizeof(p)))
|
|
err = -EFAULT;
|
|
} else
|
|
err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
|
|
break;
|
|
|
|
case SIOCDELTUNNEL:
|
|
err = -EPERM;
|
|
if (!capable(CAP_NET_ADMIN))
|
|
goto done;
|
|
|
|
if (dev == ign->fb_tunnel_dev) {
|
|
err = -EFAULT;
|
|
if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
|
|
goto done;
|
|
err = -ENOENT;
|
|
if ((t = ipgre_tunnel_locate(net, &p, 0)) == NULL)
|
|
goto done;
|
|
err = -EPERM;
|
|
if (t == netdev_priv(ign->fb_tunnel_dev))
|
|
goto done;
|
|
dev = t->dev;
|
|
}
|
|
unregister_netdevice(dev);
|
|
err = 0;
|
|
break;
|
|
|
|
default:
|
|
err = -EINVAL;
|
|
}
|
|
|
|
done:
|
|
return err;
|
|
}
|
|
|
|
static int ipgre_tunnel_change_mtu(struct net_device *dev, int new_mtu)
|
|
{
|
|
struct ip_tunnel *tunnel = netdev_priv(dev);
|
|
if (new_mtu < 68 ||
|
|
new_mtu > 0xFFF8 - dev->hard_header_len - tunnel->hlen)
|
|
return -EINVAL;
|
|
dev->mtu = new_mtu;
|
|
return 0;
|
|
}
|
|
|
|
/* Nice toy. Unfortunately, useless in real life :-)
|
|
It allows to construct virtual multiprotocol broadcast "LAN"
|
|
over the Internet, provided multicast routing is tuned.
|
|
|
|
|
|
I have no idea was this bicycle invented before me,
|
|
so that I had to set ARPHRD_IPGRE to a random value.
|
|
I have an impression, that Cisco could make something similar,
|
|
but this feature is apparently missing in IOS<=11.2(8).
|
|
|
|
I set up 10.66.66/24 and fec0:6666:6666::0/96 as virtual networks
|
|
with broadcast 224.66.66.66. If you have access to mbone, play with me :-)
|
|
|
|
ping -t 255 224.66.66.66
|
|
|
|
If nobody answers, mbone does not work.
|
|
|
|
ip tunnel add Universe mode gre remote 224.66.66.66 local <Your_real_addr> ttl 255
|
|
ip addr add 10.66.66.<somewhat>/24 dev Universe
|
|
ifconfig Universe up
|
|
ifconfig Universe add fe80::<Your_real_addr>/10
|
|
ifconfig Universe add fec0:6666:6666::<Your_real_addr>/96
|
|
ftp 10.66.66.66
|
|
...
|
|
ftp fec0:6666:6666::193.233.7.65
|
|
...
|
|
|
|
*/
|
|
|
|
static int ipgre_header(struct sk_buff *skb, struct net_device *dev,
|
|
unsigned short type,
|
|
const void *daddr, const void *saddr, unsigned int len)
|
|
{
|
|
struct ip_tunnel *t = netdev_priv(dev);
|
|
struct iphdr *iph = (struct iphdr *)skb_push(skb, t->hlen);
|
|
__be16 *p = (__be16*)(iph+1);
|
|
|
|
memcpy(iph, &t->parms.iph, sizeof(struct iphdr));
|
|
p[0] = t->parms.o_flags;
|
|
p[1] = htons(type);
|
|
|
|
/*
|
|
* Set the source hardware address.
|
|
*/
|
|
|
|
if (saddr)
|
|
memcpy(&iph->saddr, saddr, 4);
|
|
if (daddr)
|
|
memcpy(&iph->daddr, daddr, 4);
|
|
if (iph->daddr)
|
|
return t->hlen;
|
|
|
|
return -t->hlen;
|
|
}
|
|
|
|
static int ipgre_header_parse(const struct sk_buff *skb, unsigned char *haddr)
|
|
{
|
|
const struct iphdr *iph = (const struct iphdr *) skb_mac_header(skb);
|
|
memcpy(haddr, &iph->saddr, 4);
|
|
return 4;
|
|
}
|
|
|
|
static const struct header_ops ipgre_header_ops = {
|
|
.create = ipgre_header,
|
|
.parse = ipgre_header_parse,
|
|
};
|
|
|
|
#ifdef CONFIG_NET_IPGRE_BROADCAST
|
|
static int ipgre_open(struct net_device *dev)
|
|
{
|
|
struct ip_tunnel *t = netdev_priv(dev);
|
|
|
|
if (ipv4_is_multicast(t->parms.iph.daddr)) {
|
|
struct flowi4 fl4;
|
|
struct rtable *rt;
|
|
|
|
rt = ip_route_output_gre(dev_net(dev), &fl4,
|
|
t->parms.iph.daddr,
|
|
t->parms.iph.saddr,
|
|
t->parms.o_key,
|
|
RT_TOS(t->parms.iph.tos),
|
|
t->parms.link);
|
|
if (IS_ERR(rt))
|
|
return -EADDRNOTAVAIL;
|
|
dev = rt->dst.dev;
|
|
ip_rt_put(rt);
|
|
if (__in_dev_get_rtnl(dev) == NULL)
|
|
return -EADDRNOTAVAIL;
|
|
t->mlink = dev->ifindex;
|
|
ip_mc_inc_group(__in_dev_get_rtnl(dev), t->parms.iph.daddr);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int ipgre_close(struct net_device *dev)
|
|
{
|
|
struct ip_tunnel *t = netdev_priv(dev);
|
|
|
|
if (ipv4_is_multicast(t->parms.iph.daddr) && t->mlink) {
|
|
struct in_device *in_dev;
|
|
in_dev = inetdev_by_index(dev_net(dev), t->mlink);
|
|
if (in_dev)
|
|
ip_mc_dec_group(in_dev, t->parms.iph.daddr);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
#endif
|
|
|
|
static const struct net_device_ops ipgre_netdev_ops = {
|
|
.ndo_init = ipgre_tunnel_init,
|
|
.ndo_uninit = ipgre_tunnel_uninit,
|
|
#ifdef CONFIG_NET_IPGRE_BROADCAST
|
|
.ndo_open = ipgre_open,
|
|
.ndo_stop = ipgre_close,
|
|
#endif
|
|
.ndo_start_xmit = ipgre_tunnel_xmit,
|
|
.ndo_do_ioctl = ipgre_tunnel_ioctl,
|
|
.ndo_change_mtu = ipgre_tunnel_change_mtu,
|
|
.ndo_get_stats = ipgre_get_stats,
|
|
};
|
|
|
|
static void ipgre_dev_free(struct net_device *dev)
|
|
{
|
|
free_percpu(dev->tstats);
|
|
free_netdev(dev);
|
|
}
|
|
|
|
static void ipgre_tunnel_setup(struct net_device *dev)
|
|
{
|
|
dev->netdev_ops = &ipgre_netdev_ops;
|
|
dev->destructor = ipgre_dev_free;
|
|
|
|
dev->type = ARPHRD_IPGRE;
|
|
dev->needed_headroom = LL_MAX_HEADER + sizeof(struct iphdr) + 4;
|
|
dev->mtu = ETH_DATA_LEN - sizeof(struct iphdr) - 4;
|
|
dev->flags = IFF_NOARP;
|
|
dev->iflink = 0;
|
|
dev->addr_len = 4;
|
|
dev->features |= NETIF_F_NETNS_LOCAL;
|
|
dev->priv_flags &= ~IFF_XMIT_DST_RELEASE;
|
|
}
|
|
|
|
static int ipgre_tunnel_init(struct net_device *dev)
|
|
{
|
|
struct ip_tunnel *tunnel;
|
|
struct iphdr *iph;
|
|
|
|
tunnel = netdev_priv(dev);
|
|
iph = &tunnel->parms.iph;
|
|
|
|
tunnel->dev = dev;
|
|
strcpy(tunnel->parms.name, dev->name);
|
|
|
|
memcpy(dev->dev_addr, &tunnel->parms.iph.saddr, 4);
|
|
memcpy(dev->broadcast, &tunnel->parms.iph.daddr, 4);
|
|
|
|
if (iph->daddr) {
|
|
#ifdef CONFIG_NET_IPGRE_BROADCAST
|
|
if (ipv4_is_multicast(iph->daddr)) {
|
|
if (!iph->saddr)
|
|
return -EINVAL;
|
|
dev->flags = IFF_BROADCAST;
|
|
dev->header_ops = &ipgre_header_ops;
|
|
}
|
|
#endif
|
|
} else
|
|
dev->header_ops = &ipgre_header_ops;
|
|
|
|
dev->tstats = alloc_percpu(struct pcpu_tstats);
|
|
if (!dev->tstats)
|
|
return -ENOMEM;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void ipgre_fb_tunnel_init(struct net_device *dev)
|
|
{
|
|
struct ip_tunnel *tunnel = netdev_priv(dev);
|
|
struct iphdr *iph = &tunnel->parms.iph;
|
|
|
|
tunnel->dev = dev;
|
|
strcpy(tunnel->parms.name, dev->name);
|
|
|
|
iph->version = 4;
|
|
iph->protocol = IPPROTO_GRE;
|
|
iph->ihl = 5;
|
|
tunnel->hlen = sizeof(struct iphdr) + 4;
|
|
|
|
dev_hold(dev);
|
|
}
|
|
|
|
|
|
static const struct gre_protocol ipgre_protocol = {
|
|
.handler = ipgre_rcv,
|
|
.err_handler = ipgre_err,
|
|
};
|
|
|
|
static void ipgre_destroy_tunnels(struct ipgre_net *ign, struct list_head *head)
|
|
{
|
|
int prio;
|
|
|
|
for (prio = 0; prio < 4; prio++) {
|
|
int h;
|
|
for (h = 0; h < HASH_SIZE; h++) {
|
|
struct ip_tunnel *t;
|
|
|
|
t = rtnl_dereference(ign->tunnels[prio][h]);
|
|
|
|
while (t != NULL) {
|
|
unregister_netdevice_queue(t->dev, head);
|
|
t = rtnl_dereference(t->next);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
static int __net_init ipgre_init_net(struct net *net)
|
|
{
|
|
struct ipgre_net *ign = net_generic(net, ipgre_net_id);
|
|
int err;
|
|
|
|
ign->fb_tunnel_dev = alloc_netdev(sizeof(struct ip_tunnel), "gre0",
|
|
ipgre_tunnel_setup);
|
|
if (!ign->fb_tunnel_dev) {
|
|
err = -ENOMEM;
|
|
goto err_alloc_dev;
|
|
}
|
|
dev_net_set(ign->fb_tunnel_dev, net);
|
|
|
|
ipgre_fb_tunnel_init(ign->fb_tunnel_dev);
|
|
ign->fb_tunnel_dev->rtnl_link_ops = &ipgre_link_ops;
|
|
|
|
if ((err = register_netdev(ign->fb_tunnel_dev)))
|
|
goto err_reg_dev;
|
|
|
|
rcu_assign_pointer(ign->tunnels_wc[0],
|
|
netdev_priv(ign->fb_tunnel_dev));
|
|
return 0;
|
|
|
|
err_reg_dev:
|
|
ipgre_dev_free(ign->fb_tunnel_dev);
|
|
err_alloc_dev:
|
|
return err;
|
|
}
|
|
|
|
static void __net_exit ipgre_exit_net(struct net *net)
|
|
{
|
|
struct ipgre_net *ign;
|
|
LIST_HEAD(list);
|
|
|
|
ign = net_generic(net, ipgre_net_id);
|
|
rtnl_lock();
|
|
ipgre_destroy_tunnels(ign, &list);
|
|
unregister_netdevice_many(&list);
|
|
rtnl_unlock();
|
|
}
|
|
|
|
static struct pernet_operations ipgre_net_ops = {
|
|
.init = ipgre_init_net,
|
|
.exit = ipgre_exit_net,
|
|
.id = &ipgre_net_id,
|
|
.size = sizeof(struct ipgre_net),
|
|
};
|
|
|
|
static int ipgre_tunnel_validate(struct nlattr *tb[], struct nlattr *data[])
|
|
{
|
|
__be16 flags;
|
|
|
|
if (!data)
|
|
return 0;
|
|
|
|
flags = 0;
|
|
if (data[IFLA_GRE_IFLAGS])
|
|
flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]);
|
|
if (data[IFLA_GRE_OFLAGS])
|
|
flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]);
|
|
if (flags & (GRE_VERSION|GRE_ROUTING))
|
|
return -EINVAL;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int ipgre_tap_validate(struct nlattr *tb[], struct nlattr *data[])
|
|
{
|
|
__be32 daddr;
|
|
|
|
if (tb[IFLA_ADDRESS]) {
|
|
if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
|
|
return -EINVAL;
|
|
if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
|
|
return -EADDRNOTAVAIL;
|
|
}
|
|
|
|
if (!data)
|
|
goto out;
|
|
|
|
if (data[IFLA_GRE_REMOTE]) {
|
|
memcpy(&daddr, nla_data(data[IFLA_GRE_REMOTE]), 4);
|
|
if (!daddr)
|
|
return -EINVAL;
|
|
}
|
|
|
|
out:
|
|
return ipgre_tunnel_validate(tb, data);
|
|
}
|
|
|
|
static void ipgre_netlink_parms(struct nlattr *data[],
|
|
struct ip_tunnel_parm *parms)
|
|
{
|
|
memset(parms, 0, sizeof(*parms));
|
|
|
|
parms->iph.protocol = IPPROTO_GRE;
|
|
|
|
if (!data)
|
|
return;
|
|
|
|
if (data[IFLA_GRE_LINK])
|
|
parms->link = nla_get_u32(data[IFLA_GRE_LINK]);
|
|
|
|
if (data[IFLA_GRE_IFLAGS])
|
|
parms->i_flags = nla_get_be16(data[IFLA_GRE_IFLAGS]);
|
|
|
|
if (data[IFLA_GRE_OFLAGS])
|
|
parms->o_flags = nla_get_be16(data[IFLA_GRE_OFLAGS]);
|
|
|
|
if (data[IFLA_GRE_IKEY])
|
|
parms->i_key = nla_get_be32(data[IFLA_GRE_IKEY]);
|
|
|
|
if (data[IFLA_GRE_OKEY])
|
|
parms->o_key = nla_get_be32(data[IFLA_GRE_OKEY]);
|
|
|
|
if (data[IFLA_GRE_LOCAL])
|
|
parms->iph.saddr = nla_get_be32(data[IFLA_GRE_LOCAL]);
|
|
|
|
if (data[IFLA_GRE_REMOTE])
|
|
parms->iph.daddr = nla_get_be32(data[IFLA_GRE_REMOTE]);
|
|
|
|
if (data[IFLA_GRE_TTL])
|
|
parms->iph.ttl = nla_get_u8(data[IFLA_GRE_TTL]);
|
|
|
|
if (data[IFLA_GRE_TOS])
|
|
parms->iph.tos = nla_get_u8(data[IFLA_GRE_TOS]);
|
|
|
|
if (!data[IFLA_GRE_PMTUDISC] || nla_get_u8(data[IFLA_GRE_PMTUDISC]))
|
|
parms->iph.frag_off = htons(IP_DF);
|
|
}
|
|
|
|
static int ipgre_tap_init(struct net_device *dev)
|
|
{
|
|
struct ip_tunnel *tunnel;
|
|
|
|
tunnel = netdev_priv(dev);
|
|
|
|
tunnel->dev = dev;
|
|
strcpy(tunnel->parms.name, dev->name);
|
|
|
|
ipgre_tunnel_bind_dev(dev);
|
|
|
|
dev->tstats = alloc_percpu(struct pcpu_tstats);
|
|
if (!dev->tstats)
|
|
return -ENOMEM;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static const struct net_device_ops ipgre_tap_netdev_ops = {
|
|
.ndo_init = ipgre_tap_init,
|
|
.ndo_uninit = ipgre_tunnel_uninit,
|
|
.ndo_start_xmit = ipgre_tunnel_xmit,
|
|
.ndo_set_mac_address = eth_mac_addr,
|
|
.ndo_validate_addr = eth_validate_addr,
|
|
.ndo_change_mtu = ipgre_tunnel_change_mtu,
|
|
.ndo_get_stats = ipgre_get_stats,
|
|
};
|
|
|
|
static void ipgre_tap_setup(struct net_device *dev)
|
|
{
|
|
|
|
ether_setup(dev);
|
|
|
|
dev->netdev_ops = &ipgre_tap_netdev_ops;
|
|
dev->destructor = ipgre_dev_free;
|
|
|
|
dev->iflink = 0;
|
|
dev->features |= NETIF_F_NETNS_LOCAL;
|
|
}
|
|
|
|
static int ipgre_newlink(struct net *src_net, struct net_device *dev, struct nlattr *tb[],
|
|
struct nlattr *data[])
|
|
{
|
|
struct ip_tunnel *nt;
|
|
struct net *net = dev_net(dev);
|
|
struct ipgre_net *ign = net_generic(net, ipgre_net_id);
|
|
int mtu;
|
|
int err;
|
|
|
|
nt = netdev_priv(dev);
|
|
ipgre_netlink_parms(data, &nt->parms);
|
|
|
|
if (ipgre_tunnel_find(net, &nt->parms, dev->type))
|
|
return -EEXIST;
|
|
|
|
if (dev->type == ARPHRD_ETHER && !tb[IFLA_ADDRESS])
|
|
random_ether_addr(dev->dev_addr);
|
|
|
|
mtu = ipgre_tunnel_bind_dev(dev);
|
|
if (!tb[IFLA_MTU])
|
|
dev->mtu = mtu;
|
|
|
|
/* Can use a lockless transmit, unless we generate output sequences */
|
|
if (!(nt->parms.o_flags & GRE_SEQ))
|
|
dev->features |= NETIF_F_LLTX;
|
|
|
|
err = register_netdevice(dev);
|
|
if (err)
|
|
goto out;
|
|
|
|
dev_hold(dev);
|
|
ipgre_tunnel_link(ign, nt);
|
|
|
|
out:
|
|
return err;
|
|
}
|
|
|
|
static int ipgre_changelink(struct net_device *dev, struct nlattr *tb[],
|
|
struct nlattr *data[])
|
|
{
|
|
struct ip_tunnel *t, *nt;
|
|
struct net *net = dev_net(dev);
|
|
struct ipgre_net *ign = net_generic(net, ipgre_net_id);
|
|
struct ip_tunnel_parm p;
|
|
int mtu;
|
|
|
|
if (dev == ign->fb_tunnel_dev)
|
|
return -EINVAL;
|
|
|
|
nt = netdev_priv(dev);
|
|
ipgre_netlink_parms(data, &p);
|
|
|
|
t = ipgre_tunnel_locate(net, &p, 0);
|
|
|
|
if (t) {
|
|
if (t->dev != dev)
|
|
return -EEXIST;
|
|
} else {
|
|
t = nt;
|
|
|
|
if (dev->type != ARPHRD_ETHER) {
|
|
unsigned int nflags = 0;
|
|
|
|
if (ipv4_is_multicast(p.iph.daddr))
|
|
nflags = IFF_BROADCAST;
|
|
else if (p.iph.daddr)
|
|
nflags = IFF_POINTOPOINT;
|
|
|
|
if ((dev->flags ^ nflags) &
|
|
(IFF_POINTOPOINT | IFF_BROADCAST))
|
|
return -EINVAL;
|
|
}
|
|
|
|
ipgre_tunnel_unlink(ign, t);
|
|
t->parms.iph.saddr = p.iph.saddr;
|
|
t->parms.iph.daddr = p.iph.daddr;
|
|
t->parms.i_key = p.i_key;
|
|
if (dev->type != ARPHRD_ETHER) {
|
|
memcpy(dev->dev_addr, &p.iph.saddr, 4);
|
|
memcpy(dev->broadcast, &p.iph.daddr, 4);
|
|
}
|
|
ipgre_tunnel_link(ign, t);
|
|
netdev_state_change(dev);
|
|
}
|
|
|
|
t->parms.o_key = p.o_key;
|
|
t->parms.iph.ttl = p.iph.ttl;
|
|
t->parms.iph.tos = p.iph.tos;
|
|
t->parms.iph.frag_off = p.iph.frag_off;
|
|
|
|
if (t->parms.link != p.link) {
|
|
t->parms.link = p.link;
|
|
mtu = ipgre_tunnel_bind_dev(dev);
|
|
if (!tb[IFLA_MTU])
|
|
dev->mtu = mtu;
|
|
netdev_state_change(dev);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static size_t ipgre_get_size(const struct net_device *dev)
|
|
{
|
|
return
|
|
/* IFLA_GRE_LINK */
|
|
nla_total_size(4) +
|
|
/* IFLA_GRE_IFLAGS */
|
|
nla_total_size(2) +
|
|
/* IFLA_GRE_OFLAGS */
|
|
nla_total_size(2) +
|
|
/* IFLA_GRE_IKEY */
|
|
nla_total_size(4) +
|
|
/* IFLA_GRE_OKEY */
|
|
nla_total_size(4) +
|
|
/* IFLA_GRE_LOCAL */
|
|
nla_total_size(4) +
|
|
/* IFLA_GRE_REMOTE */
|
|
nla_total_size(4) +
|
|
/* IFLA_GRE_TTL */
|
|
nla_total_size(1) +
|
|
/* IFLA_GRE_TOS */
|
|
nla_total_size(1) +
|
|
/* IFLA_GRE_PMTUDISC */
|
|
nla_total_size(1) +
|
|
0;
|
|
}
|
|
|
|
static int ipgre_fill_info(struct sk_buff *skb, const struct net_device *dev)
|
|
{
|
|
struct ip_tunnel *t = netdev_priv(dev);
|
|
struct ip_tunnel_parm *p = &t->parms;
|
|
|
|
NLA_PUT_U32(skb, IFLA_GRE_LINK, p->link);
|
|
NLA_PUT_BE16(skb, IFLA_GRE_IFLAGS, p->i_flags);
|
|
NLA_PUT_BE16(skb, IFLA_GRE_OFLAGS, p->o_flags);
|
|
NLA_PUT_BE32(skb, IFLA_GRE_IKEY, p->i_key);
|
|
NLA_PUT_BE32(skb, IFLA_GRE_OKEY, p->o_key);
|
|
NLA_PUT_BE32(skb, IFLA_GRE_LOCAL, p->iph.saddr);
|
|
NLA_PUT_BE32(skb, IFLA_GRE_REMOTE, p->iph.daddr);
|
|
NLA_PUT_U8(skb, IFLA_GRE_TTL, p->iph.ttl);
|
|
NLA_PUT_U8(skb, IFLA_GRE_TOS, p->iph.tos);
|
|
NLA_PUT_U8(skb, IFLA_GRE_PMTUDISC, !!(p->iph.frag_off & htons(IP_DF)));
|
|
|
|
return 0;
|
|
|
|
nla_put_failure:
|
|
return -EMSGSIZE;
|
|
}
|
|
|
|
static const struct nla_policy ipgre_policy[IFLA_GRE_MAX + 1] = {
|
|
[IFLA_GRE_LINK] = { .type = NLA_U32 },
|
|
[IFLA_GRE_IFLAGS] = { .type = NLA_U16 },
|
|
[IFLA_GRE_OFLAGS] = { .type = NLA_U16 },
|
|
[IFLA_GRE_IKEY] = { .type = NLA_U32 },
|
|
[IFLA_GRE_OKEY] = { .type = NLA_U32 },
|
|
[IFLA_GRE_LOCAL] = { .len = FIELD_SIZEOF(struct iphdr, saddr) },
|
|
[IFLA_GRE_REMOTE] = { .len = FIELD_SIZEOF(struct iphdr, daddr) },
|
|
[IFLA_GRE_TTL] = { .type = NLA_U8 },
|
|
[IFLA_GRE_TOS] = { .type = NLA_U8 },
|
|
[IFLA_GRE_PMTUDISC] = { .type = NLA_U8 },
|
|
};
|
|
|
|
static struct rtnl_link_ops ipgre_link_ops __read_mostly = {
|
|
.kind = "gre",
|
|
.maxtype = IFLA_GRE_MAX,
|
|
.policy = ipgre_policy,
|
|
.priv_size = sizeof(struct ip_tunnel),
|
|
.setup = ipgre_tunnel_setup,
|
|
.validate = ipgre_tunnel_validate,
|
|
.newlink = ipgre_newlink,
|
|
.changelink = ipgre_changelink,
|
|
.get_size = ipgre_get_size,
|
|
.fill_info = ipgre_fill_info,
|
|
};
|
|
|
|
static struct rtnl_link_ops ipgre_tap_ops __read_mostly = {
|
|
.kind = "gretap",
|
|
.maxtype = IFLA_GRE_MAX,
|
|
.policy = ipgre_policy,
|
|
.priv_size = sizeof(struct ip_tunnel),
|
|
.setup = ipgre_tap_setup,
|
|
.validate = ipgre_tap_validate,
|
|
.newlink = ipgre_newlink,
|
|
.changelink = ipgre_changelink,
|
|
.get_size = ipgre_get_size,
|
|
.fill_info = ipgre_fill_info,
|
|
};
|
|
|
|
/*
|
|
* And now the modules code and kernel interface.
|
|
*/
|
|
|
|
static int __init ipgre_init(void)
|
|
{
|
|
int err;
|
|
|
|
printk(KERN_INFO "GRE over IPv4 tunneling driver\n");
|
|
|
|
err = register_pernet_device(&ipgre_net_ops);
|
|
if (err < 0)
|
|
return err;
|
|
|
|
err = gre_add_protocol(&ipgre_protocol, GREPROTO_CISCO);
|
|
if (err < 0) {
|
|
printk(KERN_INFO "ipgre init: can't add protocol\n");
|
|
goto add_proto_failed;
|
|
}
|
|
|
|
err = rtnl_link_register(&ipgre_link_ops);
|
|
if (err < 0)
|
|
goto rtnl_link_failed;
|
|
|
|
err = rtnl_link_register(&ipgre_tap_ops);
|
|
if (err < 0)
|
|
goto tap_ops_failed;
|
|
|
|
out:
|
|
return err;
|
|
|
|
tap_ops_failed:
|
|
rtnl_link_unregister(&ipgre_link_ops);
|
|
rtnl_link_failed:
|
|
gre_del_protocol(&ipgre_protocol, GREPROTO_CISCO);
|
|
add_proto_failed:
|
|
unregister_pernet_device(&ipgre_net_ops);
|
|
goto out;
|
|
}
|
|
|
|
static void __exit ipgre_fini(void)
|
|
{
|
|
rtnl_link_unregister(&ipgre_tap_ops);
|
|
rtnl_link_unregister(&ipgre_link_ops);
|
|
if (gre_del_protocol(&ipgre_protocol, GREPROTO_CISCO) < 0)
|
|
printk(KERN_INFO "ipgre close: can't remove protocol\n");
|
|
unregister_pernet_device(&ipgre_net_ops);
|
|
}
|
|
|
|
module_init(ipgre_init);
|
|
module_exit(ipgre_fini);
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_ALIAS_RTNL_LINK("gre");
|
|
MODULE_ALIAS_RTNL_LINK("gretap");
|
|
MODULE_ALIAS_NETDEV("gre0");
|