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![Nicolas Dichtel](/assets/img/avatar_default.png)
Before the patch, it was possible to add two times the same tunnel:
ip l a gre1 type gre remote 10.16.0.121 local 10.16.0.249
ip l a gre2 type gre remote 10.16.0.121 local 10.16.0.249
It was possible, because ip_tunnel_newlink() calls ip_tunnel_find() with the
argument dev->type, which was set only later (when calling ndo_init handler
in register_netdevice()). Let's set this type in the setup handler, which is
called before newlink handler.
Introduced by commit c544193214
("GRE: Refactor GRE tunneling code.").
CC: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
837 lines
22 KiB
C
837 lines
22 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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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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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/ip_tunnels.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 maintaining 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, ttl 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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rapidly 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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Alexey Kuznetsov.
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*/
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static bool log_ecn_error = true;
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module_param(log_ecn_error, bool, 0644);
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MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN");
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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 int ipgre_net_id __read_mostly;
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static int gre_tap_net_id __read_mostly;
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static int ipgre_err(struct sk_buff *skb, u32 info,
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const struct tnl_ptk_info *tpi)
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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
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state for keyed GRE tunnels with enabled checksum. Tell
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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 standards established
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by themselves???
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*/
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struct net *net = dev_net(skb->dev);
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struct ip_tunnel_net *itn;
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const struct iphdr *iph;
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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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switch (type) {
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default:
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case ICMP_PARAMETERPROB:
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return PACKET_RCVD;
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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 PACKET_RCVD;
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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 PACKET_RCVD;
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break;
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case ICMP_REDIRECT:
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break;
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}
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if (tpi->proto == htons(ETH_P_TEB))
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itn = net_generic(net, gre_tap_net_id);
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else
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itn = net_generic(net, ipgre_net_id);
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iph = (const struct iphdr *)(icmp_hdr(skb) + 1);
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t = ip_tunnel_lookup(itn, skb->dev->ifindex, tpi->flags,
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iph->daddr, iph->saddr, tpi->key);
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if (t == NULL)
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return PACKET_REJECT;
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if (t->parms.iph.daddr == 0 ||
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ipv4_is_multicast(t->parms.iph.daddr))
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return PACKET_RCVD;
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if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED)
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return PACKET_RCVD;
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if (time_before(jiffies, t->err_time + IPTUNNEL_ERR_TIMEO))
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t->err_count++;
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else
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t->err_count = 1;
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t->err_time = jiffies;
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return PACKET_RCVD;
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}
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static int ipgre_rcv(struct sk_buff *skb, const struct tnl_ptk_info *tpi)
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{
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struct net *net = dev_net(skb->dev);
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struct ip_tunnel_net *itn;
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const struct iphdr *iph;
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struct ip_tunnel *tunnel;
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if (tpi->proto == htons(ETH_P_TEB))
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itn = net_generic(net, gre_tap_net_id);
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else
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itn = net_generic(net, ipgre_net_id);
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iph = ip_hdr(skb);
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tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex, tpi->flags,
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iph->saddr, iph->daddr, tpi->key);
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if (tunnel) {
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skb_pop_mac_header(skb);
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ip_tunnel_rcv(tunnel, skb, tpi, log_ecn_error);
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return PACKET_RCVD;
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}
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return PACKET_REJECT;
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}
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static void __gre_xmit(struct sk_buff *skb, struct net_device *dev,
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const struct iphdr *tnl_params,
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__be16 proto)
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{
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struct ip_tunnel *tunnel = netdev_priv(dev);
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struct tnl_ptk_info tpi;
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tpi.flags = tunnel->parms.o_flags;
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tpi.proto = proto;
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tpi.key = tunnel->parms.o_key;
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if (tunnel->parms.o_flags & TUNNEL_SEQ)
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tunnel->o_seqno++;
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tpi.seq = htonl(tunnel->o_seqno);
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/* Push GRE header. */
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gre_build_header(skb, &tpi, tunnel->hlen);
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ip_tunnel_xmit(skb, dev, tnl_params, tnl_params->protocol);
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}
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static netdev_tx_t ipgre_xmit(struct sk_buff *skb,
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struct net_device *dev)
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{
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struct ip_tunnel *tunnel = netdev_priv(dev);
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const struct iphdr *tnl_params;
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skb = gre_handle_offloads(skb, !!(tunnel->parms.o_flags&TUNNEL_CSUM));
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if (IS_ERR(skb))
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goto out;
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if (dev->header_ops) {
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/* Need space for new headers */
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if (skb_cow_head(skb, dev->needed_headroom -
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(tunnel->hlen + sizeof(struct iphdr))))
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goto free_skb;
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tnl_params = (const struct iphdr *)skb->data;
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/* Pull skb since ip_tunnel_xmit() needs skb->data pointing
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* to gre header.
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*/
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skb_pull(skb, tunnel->hlen + sizeof(struct iphdr));
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} else {
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if (skb_cow_head(skb, dev->needed_headroom))
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goto free_skb;
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tnl_params = &tunnel->parms.iph;
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}
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__gre_xmit(skb, dev, tnl_params, skb->protocol);
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return NETDEV_TX_OK;
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free_skb:
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kfree_skb(skb);
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out:
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dev->stats.tx_dropped++;
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return NETDEV_TX_OK;
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}
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static netdev_tx_t gre_tap_xmit(struct sk_buff *skb,
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struct net_device *dev)
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{
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struct ip_tunnel *tunnel = netdev_priv(dev);
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skb = gre_handle_offloads(skb, !!(tunnel->parms.o_flags&TUNNEL_CSUM));
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if (IS_ERR(skb))
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goto out;
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if (skb_cow_head(skb, dev->needed_headroom))
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goto free_skb;
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__gre_xmit(skb, dev, &tunnel->parms.iph, htons(ETH_P_TEB));
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return NETDEV_TX_OK;
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free_skb:
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kfree_skb(skb);
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out:
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dev->stats.tx_dropped++;
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return NETDEV_TX_OK;
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}
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static int ipgre_tunnel_ioctl(struct net_device *dev,
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struct ifreq *ifr, int cmd)
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{
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int err = 0;
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struct ip_tunnel_parm p;
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if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
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return -EFAULT;
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if (cmd == SIOCADDTUNNEL || cmd == SIOCCHGTUNNEL) {
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if (p.iph.version != 4 || p.iph.protocol != IPPROTO_GRE ||
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p.iph.ihl != 5 || (p.iph.frag_off&htons(~IP_DF)) ||
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((p.i_flags|p.o_flags)&(GRE_VERSION|GRE_ROUTING)))
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return -EINVAL;
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}
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p.i_flags = gre_flags_to_tnl_flags(p.i_flags);
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p.o_flags = gre_flags_to_tnl_flags(p.o_flags);
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err = ip_tunnel_ioctl(dev, &p, cmd);
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if (err)
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return err;
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p.i_flags = tnl_flags_to_gre_flags(p.i_flags);
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p.o_flags = tnl_flags_to_gre_flags(p.o_flags);
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if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
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return -EFAULT;
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return 0;
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}
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/* Nice toy. Unfortunately, useless in real life :-)
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It allows to construct virtual multiprotocol broadcast "LAN"
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over the Internet, provided multicast routing is tuned.
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I have no idea was this bicycle invented before me,
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so that I had to set ARPHRD_IPGRE to a random value.
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I have an impression, that Cisco could make something similar,
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but this feature is apparently missing in IOS<=11.2(8).
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I set up 10.66.66/24 and fec0:6666:6666::0/96 as virtual networks
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with broadcast 224.66.66.66. If you have access to mbone, play with me :-)
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ping -t 255 224.66.66.66
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If nobody answers, mbone does not work.
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ip tunnel add Universe mode gre remote 224.66.66.66 local <Your_real_addr> ttl 255
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ip addr add 10.66.66.<somewhat>/24 dev Universe
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ifconfig Universe up
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ifconfig Universe add fe80::<Your_real_addr>/10
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ifconfig Universe add fec0:6666:6666::<Your_real_addr>/96
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ftp 10.66.66.66
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...
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ftp fec0:6666:6666::193.233.7.65
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...
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*/
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static int ipgre_header(struct sk_buff *skb, struct net_device *dev,
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unsigned short type,
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const void *daddr, const void *saddr, unsigned int len)
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{
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struct ip_tunnel *t = netdev_priv(dev);
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struct iphdr *iph;
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struct gre_base_hdr *greh;
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iph = (struct iphdr *)skb_push(skb, t->hlen + sizeof(*iph));
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greh = (struct gre_base_hdr *)(iph+1);
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greh->flags = tnl_flags_to_gre_flags(t->parms.o_flags);
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greh->protocol = htons(type);
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memcpy(iph, &t->parms.iph, sizeof(struct iphdr));
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/* Set the source hardware address. */
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if (saddr)
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memcpy(&iph->saddr, saddr, 4);
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if (daddr)
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memcpy(&iph->daddr, daddr, 4);
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if (iph->daddr)
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return t->hlen + sizeof(*iph);
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return -(t->hlen + sizeof(*iph));
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}
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static int ipgre_header_parse(const struct sk_buff *skb, unsigned char *haddr)
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{
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const struct iphdr *iph = (const struct iphdr *) skb_mac_header(skb);
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memcpy(haddr, &iph->saddr, 4);
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return 4;
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}
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|
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static const struct header_ops ipgre_header_ops = {
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.create = ipgre_header,
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.parse = ipgre_header_parse,
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};
|
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|
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#ifdef CONFIG_NET_IPGRE_BROADCAST
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static int ipgre_open(struct net_device *dev)
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{
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struct ip_tunnel *t = netdev_priv(dev);
|
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|
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if (ipv4_is_multicast(t->parms.iph.daddr)) {
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struct flowi4 fl4;
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struct rtable *rt;
|
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rt = ip_route_output_gre(dev_net(dev), &fl4,
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t->parms.iph.daddr,
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t->parms.iph.saddr,
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t->parms.o_key,
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RT_TOS(t->parms.iph.tos),
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t->parms.link);
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if (IS_ERR(rt))
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return -EADDRNOTAVAIL;
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dev = rt->dst.dev;
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ip_rt_put(rt);
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if (__in_dev_get_rtnl(dev) == NULL)
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return -EADDRNOTAVAIL;
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t->mlink = dev->ifindex;
|
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ip_mc_inc_group(__in_dev_get_rtnl(dev), t->parms.iph.daddr);
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}
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return 0;
|
|
}
|
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|
|
static int ipgre_close(struct net_device *dev)
|
|
{
|
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struct ip_tunnel *t = netdev_priv(dev);
|
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|
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if (ipv4_is_multicast(t->parms.iph.daddr) && t->mlink) {
|
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struct in_device *in_dev;
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in_dev = inetdev_by_index(dev_net(dev), t->mlink);
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if (in_dev)
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ip_mc_dec_group(in_dev, t->parms.iph.daddr);
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}
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return 0;
|
|
}
|
|
#endif
|
|
|
|
static const struct net_device_ops ipgre_netdev_ops = {
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|
.ndo_init = ipgre_tunnel_init,
|
|
.ndo_uninit = ip_tunnel_uninit,
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|
#ifdef CONFIG_NET_IPGRE_BROADCAST
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|
.ndo_open = ipgre_open,
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.ndo_stop = ipgre_close,
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#endif
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.ndo_start_xmit = ipgre_xmit,
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.ndo_do_ioctl = ipgre_tunnel_ioctl,
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.ndo_change_mtu = ip_tunnel_change_mtu,
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.ndo_get_stats64 = ip_tunnel_get_stats64,
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|
};
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|
|
#define GRE_FEATURES (NETIF_F_SG | \
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NETIF_F_FRAGLIST | \
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NETIF_F_HIGHDMA | \
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NETIF_F_HW_CSUM)
|
|
|
|
static void ipgre_tunnel_setup(struct net_device *dev)
|
|
{
|
|
dev->netdev_ops = &ipgre_netdev_ops;
|
|
dev->type = ARPHRD_IPGRE;
|
|
ip_tunnel_setup(dev, ipgre_net_id);
|
|
}
|
|
|
|
static void __gre_tunnel_init(struct net_device *dev)
|
|
{
|
|
struct ip_tunnel *tunnel;
|
|
|
|
tunnel = netdev_priv(dev);
|
|
tunnel->hlen = ip_gre_calc_hlen(tunnel->parms.o_flags);
|
|
tunnel->parms.iph.protocol = IPPROTO_GRE;
|
|
|
|
dev->needed_headroom = LL_MAX_HEADER + sizeof(struct iphdr) + 4;
|
|
dev->mtu = ETH_DATA_LEN - sizeof(struct iphdr) - 4;
|
|
|
|
dev->features |= NETIF_F_NETNS_LOCAL | GRE_FEATURES;
|
|
dev->hw_features |= GRE_FEATURES;
|
|
|
|
if (!(tunnel->parms.o_flags & TUNNEL_SEQ)) {
|
|
/* TCP offload with GRE SEQ is not supported. */
|
|
dev->features |= NETIF_F_GSO_SOFTWARE;
|
|
dev->hw_features |= NETIF_F_GSO_SOFTWARE;
|
|
/* Can use a lockless transmit, unless we generate
|
|
* output sequences
|
|
*/
|
|
dev->features |= NETIF_F_LLTX;
|
|
}
|
|
}
|
|
|
|
static int ipgre_tunnel_init(struct net_device *dev)
|
|
{
|
|
struct ip_tunnel *tunnel = netdev_priv(dev);
|
|
struct iphdr *iph = &tunnel->parms.iph;
|
|
|
|
__gre_tunnel_init(dev);
|
|
|
|
memcpy(dev->dev_addr, &iph->saddr, 4);
|
|
memcpy(dev->broadcast, &iph->daddr, 4);
|
|
|
|
dev->flags = IFF_NOARP;
|
|
dev->priv_flags &= ~IFF_XMIT_DST_RELEASE;
|
|
dev->addr_len = 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;
|
|
|
|
return ip_tunnel_init(dev);
|
|
}
|
|
|
|
static struct gre_cisco_protocol ipgre_protocol = {
|
|
.handler = ipgre_rcv,
|
|
.err_handler = ipgre_err,
|
|
.priority = 0,
|
|
};
|
|
|
|
static int __net_init ipgre_init_net(struct net *net)
|
|
{
|
|
return ip_tunnel_init_net(net, ipgre_net_id, &ipgre_link_ops, NULL);
|
|
}
|
|
|
|
static void __net_exit ipgre_exit_net(struct net *net)
|
|
{
|
|
struct ip_tunnel_net *itn = net_generic(net, ipgre_net_id);
|
|
ip_tunnel_delete_net(itn, &ipgre_link_ops);
|
|
}
|
|
|
|
static struct pernet_operations ipgre_net_ops = {
|
|
.init = ipgre_init_net,
|
|
.exit = ipgre_exit_net,
|
|
.id = &ipgre_net_id,
|
|
.size = sizeof(struct ip_tunnel_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 nlattr *tb[],
|
|
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 = gre_flags_to_tnl_flags(nla_get_be16(data[IFLA_GRE_IFLAGS]));
|
|
|
|
if (data[IFLA_GRE_OFLAGS])
|
|
parms->o_flags = gre_flags_to_tnl_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 gre_tap_init(struct net_device *dev)
|
|
{
|
|
__gre_tunnel_init(dev);
|
|
|
|
return ip_tunnel_init(dev);
|
|
}
|
|
|
|
static const struct net_device_ops gre_tap_netdev_ops = {
|
|
.ndo_init = gre_tap_init,
|
|
.ndo_uninit = ip_tunnel_uninit,
|
|
.ndo_start_xmit = gre_tap_xmit,
|
|
.ndo_set_mac_address = eth_mac_addr,
|
|
.ndo_validate_addr = eth_validate_addr,
|
|
.ndo_change_mtu = ip_tunnel_change_mtu,
|
|
.ndo_get_stats64 = ip_tunnel_get_stats64,
|
|
};
|
|
|
|
static void ipgre_tap_setup(struct net_device *dev)
|
|
{
|
|
ether_setup(dev);
|
|
dev->netdev_ops = &gre_tap_netdev_ops;
|
|
ip_tunnel_setup(dev, gre_tap_net_id);
|
|
}
|
|
|
|
static int ipgre_newlink(struct net *src_net, struct net_device *dev,
|
|
struct nlattr *tb[], struct nlattr *data[])
|
|
{
|
|
struct ip_tunnel_parm p;
|
|
|
|
ipgre_netlink_parms(data, tb, &p);
|
|
return ip_tunnel_newlink(dev, tb, &p);
|
|
}
|
|
|
|
static int ipgre_changelink(struct net_device *dev, struct nlattr *tb[],
|
|
struct nlattr *data[])
|
|
{
|
|
struct ip_tunnel_parm p;
|
|
|
|
ipgre_netlink_parms(data, tb, &p);
|
|
return ip_tunnel_changelink(dev, tb, &p);
|
|
}
|
|
|
|
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;
|
|
|
|
if (nla_put_u32(skb, IFLA_GRE_LINK, p->link) ||
|
|
nla_put_be16(skb, IFLA_GRE_IFLAGS, tnl_flags_to_gre_flags(p->i_flags)) ||
|
|
nla_put_be16(skb, IFLA_GRE_OFLAGS, tnl_flags_to_gre_flags(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))))
|
|
goto nla_put_failure;
|
|
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,
|
|
.dellink = ip_tunnel_dellink,
|
|
.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,
|
|
.dellink = ip_tunnel_dellink,
|
|
.get_size = ipgre_get_size,
|
|
.fill_info = ipgre_fill_info,
|
|
};
|
|
|
|
static int __net_init ipgre_tap_init_net(struct net *net)
|
|
{
|
|
return ip_tunnel_init_net(net, gre_tap_net_id, &ipgre_tap_ops, NULL);
|
|
}
|
|
|
|
static void __net_exit ipgre_tap_exit_net(struct net *net)
|
|
{
|
|
struct ip_tunnel_net *itn = net_generic(net, gre_tap_net_id);
|
|
ip_tunnel_delete_net(itn, &ipgre_tap_ops);
|
|
}
|
|
|
|
static struct pernet_operations ipgre_tap_net_ops = {
|
|
.init = ipgre_tap_init_net,
|
|
.exit = ipgre_tap_exit_net,
|
|
.id = &gre_tap_net_id,
|
|
.size = sizeof(struct ip_tunnel_net),
|
|
};
|
|
|
|
static int __init ipgre_init(void)
|
|
{
|
|
int err;
|
|
|
|
pr_info("GRE over IPv4 tunneling driver\n");
|
|
|
|
err = register_pernet_device(&ipgre_net_ops);
|
|
if (err < 0)
|
|
return err;
|
|
|
|
err = register_pernet_device(&ipgre_tap_net_ops);
|
|
if (err < 0)
|
|
goto pnet_tap_faied;
|
|
|
|
err = gre_cisco_register(&ipgre_protocol);
|
|
if (err < 0) {
|
|
pr_info("%s: can't add protocol\n", __func__);
|
|
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;
|
|
|
|
return 0;
|
|
|
|
tap_ops_failed:
|
|
rtnl_link_unregister(&ipgre_link_ops);
|
|
rtnl_link_failed:
|
|
gre_cisco_unregister(&ipgre_protocol);
|
|
add_proto_failed:
|
|
unregister_pernet_device(&ipgre_tap_net_ops);
|
|
pnet_tap_faied:
|
|
unregister_pernet_device(&ipgre_net_ops);
|
|
return err;
|
|
}
|
|
|
|
static void __exit ipgre_fini(void)
|
|
{
|
|
rtnl_link_unregister(&ipgre_tap_ops);
|
|
rtnl_link_unregister(&ipgre_link_ops);
|
|
gre_cisco_unregister(&ipgre_protocol);
|
|
unregister_pernet_device(&ipgre_tap_net_ops);
|
|
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");
|
|
MODULE_ALIAS_NETDEV("gretap0");
|