1649 lines
42 KiB
C
1649 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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#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 <linux/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/if_vlan.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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#include <net/dst_metadata.h>
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#include <net/erspan.h>
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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 void erspan_build_header(struct sk_buff *skb,
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__be32 id, u32 index, bool truncate);
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static unsigned int ipgre_net_id __read_mostly;
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static unsigned int gre_tap_net_id __read_mostly;
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static unsigned int erspan_net_id __read_mostly;
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static void 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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unsigned int data_len = 0;
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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;
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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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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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data_len = icmp_hdr(skb)->un.reserved[1] * 4; /* RFC 4884 4.1 */
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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)
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return;
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#if IS_ENABLED(CONFIG_IPV6)
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if (tpi->proto == htons(ETH_P_IPV6) &&
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!ip6_err_gen_icmpv6_unreach(skb, iph->ihl * 4 + tpi->hdr_len,
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type, data_len))
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return;
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#endif
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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;
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if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED)
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return;
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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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}
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static void gre_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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*
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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
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* GRE tunnels with enabled checksum. Tell them "thank you".
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*
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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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const struct iphdr *iph = (struct iphdr *)skb->data;
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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 tnl_ptk_info tpi;
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bool csum_err = false;
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if (gre_parse_header(skb, &tpi, &csum_err, htons(ETH_P_IP),
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iph->ihl * 4) < 0) {
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if (!csum_err) /* ignore csum errors. */
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return;
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}
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if (type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED) {
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ipv4_update_pmtu(skb, dev_net(skb->dev), info,
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skb->dev->ifindex, 0, IPPROTO_GRE, 0);
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return;
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}
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if (type == ICMP_REDIRECT) {
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ipv4_redirect(skb, dev_net(skb->dev), skb->dev->ifindex, 0,
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IPPROTO_GRE, 0);
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return;
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}
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ipgre_err(skb, info, &tpi);
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}
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static int erspan_rcv(struct sk_buff *skb, struct tnl_ptk_info *tpi,
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int gre_hdr_len)
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{
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struct net *net = dev_net(skb->dev);
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struct metadata_dst *tun_dst = NULL;
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struct ip_tunnel_net *itn;
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struct ip_tunnel *tunnel;
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struct erspanhdr *ershdr;
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const struct iphdr *iph;
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__be32 session_id;
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__be32 index;
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int len;
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itn = net_generic(net, erspan_net_id);
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len = gre_hdr_len + sizeof(*ershdr);
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if (unlikely(!pskb_may_pull(skb, len)))
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return -ENOMEM;
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iph = ip_hdr(skb);
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ershdr = (struct erspanhdr *)(skb->data + gre_hdr_len);
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/* The original GRE header does not have key field,
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* Use ERSPAN 10-bit session ID as key.
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*/
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session_id = cpu_to_be32(ntohs(ershdr->session_id));
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tpi->key = session_id;
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index = ershdr->md.index;
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tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex,
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tpi->flags | TUNNEL_KEY,
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iph->saddr, iph->daddr, tpi->key);
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if (tunnel) {
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if (__iptunnel_pull_header(skb,
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gre_hdr_len + sizeof(*ershdr),
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htons(ETH_P_TEB),
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false, false) < 0)
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goto drop;
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if (tunnel->collect_md) {
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struct ip_tunnel_info *info;
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struct erspan_metadata *md;
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__be64 tun_id;
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__be16 flags;
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tpi->flags |= TUNNEL_KEY;
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flags = tpi->flags;
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tun_id = key32_to_tunnel_id(tpi->key);
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tun_dst = ip_tun_rx_dst(skb, flags,
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tun_id, sizeof(*md));
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if (!tun_dst)
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return PACKET_REJECT;
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md = ip_tunnel_info_opts(&tun_dst->u.tun_info);
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if (!md)
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return PACKET_REJECT;
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md->index = index;
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info = &tun_dst->u.tun_info;
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info->key.tun_flags |= TUNNEL_ERSPAN_OPT;
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info->options_len = sizeof(*md);
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} else {
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tunnel->index = ntohl(index);
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}
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skb_reset_mac_header(skb);
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ip_tunnel_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error);
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return PACKET_RCVD;
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}
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drop:
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kfree_skb(skb);
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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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struct ip_tunnel_net *itn, int hdr_len, bool raw_proto)
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{
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struct metadata_dst *tun_dst = NULL;
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const struct iphdr *iph;
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struct ip_tunnel *tunnel;
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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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if (__iptunnel_pull_header(skb, hdr_len, tpi->proto,
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raw_proto, false) < 0)
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goto drop;
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if (tunnel->dev->type != ARPHRD_NONE)
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skb_pop_mac_header(skb);
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else
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skb_reset_mac_header(skb);
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if (tunnel->collect_md) {
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__be16 flags;
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__be64 tun_id;
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flags = tpi->flags & (TUNNEL_CSUM | TUNNEL_KEY);
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tun_id = key32_to_tunnel_id(tpi->key);
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tun_dst = ip_tun_rx_dst(skb, flags, tun_id, 0);
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if (!tun_dst)
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return PACKET_REJECT;
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}
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ip_tunnel_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error);
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return PACKET_RCVD;
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}
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return PACKET_NEXT;
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drop:
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kfree_skb(skb);
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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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int hdr_len)
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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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int res;
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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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res = __ipgre_rcv(skb, tpi, itn, hdr_len, false);
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if (res == PACKET_NEXT && tpi->proto == htons(ETH_P_TEB)) {
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/* ipgre tunnels in collect metadata mode should receive
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* also ETH_P_TEB traffic.
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*/
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itn = net_generic(net, ipgre_net_id);
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res = __ipgre_rcv(skb, tpi, itn, hdr_len, true);
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}
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return res;
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}
|
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|
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static int gre_rcv(struct sk_buff *skb)
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{
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struct tnl_ptk_info tpi;
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bool csum_err = false;
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int hdr_len;
|
|
|
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#ifdef CONFIG_NET_IPGRE_BROADCAST
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if (ipv4_is_multicast(ip_hdr(skb)->daddr)) {
|
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/* Looped back packet, drop it! */
|
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if (rt_is_output_route(skb_rtable(skb)))
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goto drop;
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}
|
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#endif
|
|
|
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hdr_len = gre_parse_header(skb, &tpi, &csum_err, htons(ETH_P_IP), 0);
|
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if (hdr_len < 0)
|
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goto drop;
|
|
|
|
if (unlikely(tpi.proto == htons(ETH_P_ERSPAN))) {
|
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if (erspan_rcv(skb, &tpi, hdr_len) == PACKET_RCVD)
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return 0;
|
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}
|
|
|
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if (ipgre_rcv(skb, &tpi, hdr_len) == PACKET_RCVD)
|
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return 0;
|
|
|
|
icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0);
|
|
drop:
|
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kfree_skb(skb);
|
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return 0;
|
|
}
|
|
|
|
static void __gre_xmit(struct sk_buff *skb, struct net_device *dev,
|
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const struct iphdr *tnl_params,
|
|
__be16 proto)
|
|
{
|
|
struct ip_tunnel *tunnel = netdev_priv(dev);
|
|
|
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if (tunnel->parms.o_flags & TUNNEL_SEQ)
|
|
tunnel->o_seqno++;
|
|
|
|
/* Push GRE header. */
|
|
gre_build_header(skb, tunnel->tun_hlen,
|
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tunnel->parms.o_flags, proto, tunnel->parms.o_key,
|
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htonl(tunnel->o_seqno));
|
|
|
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ip_tunnel_xmit(skb, dev, tnl_params, tnl_params->protocol);
|
|
}
|
|
|
|
static int gre_handle_offloads(struct sk_buff *skb, bool csum)
|
|
{
|
|
return iptunnel_handle_offloads(skb, csum ? SKB_GSO_GRE_CSUM : SKB_GSO_GRE);
|
|
}
|
|
|
|
static struct rtable *gre_get_rt(struct sk_buff *skb,
|
|
struct net_device *dev,
|
|
struct flowi4 *fl,
|
|
const struct ip_tunnel_key *key)
|
|
{
|
|
struct net *net = dev_net(dev);
|
|
|
|
memset(fl, 0, sizeof(*fl));
|
|
fl->daddr = key->u.ipv4.dst;
|
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fl->saddr = key->u.ipv4.src;
|
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fl->flowi4_tos = RT_TOS(key->tos);
|
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fl->flowi4_mark = skb->mark;
|
|
fl->flowi4_proto = IPPROTO_GRE;
|
|
|
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return ip_route_output_key(net, fl);
|
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}
|
|
|
|
static struct rtable *prepare_fb_xmit(struct sk_buff *skb,
|
|
struct net_device *dev,
|
|
struct flowi4 *fl,
|
|
int tunnel_hlen)
|
|
{
|
|
struct ip_tunnel_info *tun_info;
|
|
const struct ip_tunnel_key *key;
|
|
struct rtable *rt = NULL;
|
|
int min_headroom;
|
|
bool use_cache;
|
|
int err;
|
|
|
|
tun_info = skb_tunnel_info(skb);
|
|
key = &tun_info->key;
|
|
use_cache = ip_tunnel_dst_cache_usable(skb, tun_info);
|
|
|
|
if (use_cache)
|
|
rt = dst_cache_get_ip4(&tun_info->dst_cache, &fl->saddr);
|
|
if (!rt) {
|
|
rt = gre_get_rt(skb, dev, fl, key);
|
|
if (IS_ERR(rt))
|
|
goto err_free_skb;
|
|
if (use_cache)
|
|
dst_cache_set_ip4(&tun_info->dst_cache, &rt->dst,
|
|
fl->saddr);
|
|
}
|
|
|
|
min_headroom = LL_RESERVED_SPACE(rt->dst.dev) + rt->dst.header_len
|
|
+ tunnel_hlen + sizeof(struct iphdr);
|
|
if (skb_headroom(skb) < min_headroom || skb_header_cloned(skb)) {
|
|
int head_delta = SKB_DATA_ALIGN(min_headroom -
|
|
skb_headroom(skb) +
|
|
16);
|
|
err = pskb_expand_head(skb, max_t(int, head_delta, 0),
|
|
0, GFP_ATOMIC);
|
|
if (unlikely(err))
|
|
goto err_free_rt;
|
|
}
|
|
return rt;
|
|
|
|
err_free_rt:
|
|
ip_rt_put(rt);
|
|
err_free_skb:
|
|
kfree_skb(skb);
|
|
dev->stats.tx_dropped++;
|
|
return NULL;
|
|
}
|
|
|
|
static void gre_fb_xmit(struct sk_buff *skb, struct net_device *dev,
|
|
__be16 proto)
|
|
{
|
|
struct ip_tunnel_info *tun_info;
|
|
const struct ip_tunnel_key *key;
|
|
struct rtable *rt = NULL;
|
|
struct flowi4 fl;
|
|
int tunnel_hlen;
|
|
__be16 df, flags;
|
|
|
|
tun_info = skb_tunnel_info(skb);
|
|
if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX) ||
|
|
ip_tunnel_info_af(tun_info) != AF_INET))
|
|
goto err_free_skb;
|
|
|
|
key = &tun_info->key;
|
|
tunnel_hlen = gre_calc_hlen(key->tun_flags);
|
|
|
|
rt = prepare_fb_xmit(skb, dev, &fl, tunnel_hlen);
|
|
if (!rt)
|
|
return;
|
|
|
|
/* Push Tunnel header. */
|
|
if (gre_handle_offloads(skb, !!(tun_info->key.tun_flags & TUNNEL_CSUM)))
|
|
goto err_free_rt;
|
|
|
|
flags = tun_info->key.tun_flags & (TUNNEL_CSUM | TUNNEL_KEY);
|
|
gre_build_header(skb, tunnel_hlen, flags, proto,
|
|
tunnel_id_to_key32(tun_info->key.tun_id), 0);
|
|
|
|
df = key->tun_flags & TUNNEL_DONT_FRAGMENT ? htons(IP_DF) : 0;
|
|
|
|
iptunnel_xmit(skb->sk, rt, skb, fl.saddr, key->u.ipv4.dst, IPPROTO_GRE,
|
|
key->tos, key->ttl, df, false);
|
|
return;
|
|
|
|
err_free_rt:
|
|
ip_rt_put(rt);
|
|
err_free_skb:
|
|
kfree_skb(skb);
|
|
dev->stats.tx_dropped++;
|
|
}
|
|
|
|
static void erspan_fb_xmit(struct sk_buff *skb, struct net_device *dev,
|
|
__be16 proto)
|
|
{
|
|
struct ip_tunnel *tunnel = netdev_priv(dev);
|
|
struct ip_tunnel_info *tun_info;
|
|
const struct ip_tunnel_key *key;
|
|
struct erspan_metadata *md;
|
|
struct rtable *rt = NULL;
|
|
bool truncate = false;
|
|
struct flowi4 fl;
|
|
int tunnel_hlen;
|
|
__be16 df;
|
|
|
|
tun_info = skb_tunnel_info(skb);
|
|
if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX) ||
|
|
ip_tunnel_info_af(tun_info) != AF_INET))
|
|
goto err_free_skb;
|
|
|
|
key = &tun_info->key;
|
|
|
|
/* ERSPAN has fixed 8 byte GRE header */
|
|
tunnel_hlen = 8 + sizeof(struct erspanhdr);
|
|
|
|
rt = prepare_fb_xmit(skb, dev, &fl, tunnel_hlen);
|
|
if (!rt)
|
|
return;
|
|
|
|
if (gre_handle_offloads(skb, false))
|
|
goto err_free_rt;
|
|
|
|
if (skb->len > dev->mtu) {
|
|
pskb_trim(skb, dev->mtu);
|
|
truncate = true;
|
|
}
|
|
|
|
md = ip_tunnel_info_opts(tun_info);
|
|
if (!md)
|
|
goto err_free_rt;
|
|
|
|
erspan_build_header(skb, tunnel_id_to_key32(key->tun_id),
|
|
ntohl(md->index), truncate);
|
|
|
|
gre_build_header(skb, 8, TUNNEL_SEQ,
|
|
htons(ETH_P_ERSPAN), 0, htonl(tunnel->o_seqno++));
|
|
|
|
df = key->tun_flags & TUNNEL_DONT_FRAGMENT ? htons(IP_DF) : 0;
|
|
|
|
iptunnel_xmit(skb->sk, rt, skb, fl.saddr, key->u.ipv4.dst, IPPROTO_GRE,
|
|
key->tos, key->ttl, df, false);
|
|
return;
|
|
|
|
err_free_rt:
|
|
ip_rt_put(rt);
|
|
err_free_skb:
|
|
kfree_skb(skb);
|
|
dev->stats.tx_dropped++;
|
|
}
|
|
|
|
static int gre_fill_metadata_dst(struct net_device *dev, struct sk_buff *skb)
|
|
{
|
|
struct ip_tunnel_info *info = skb_tunnel_info(skb);
|
|
struct rtable *rt;
|
|
struct flowi4 fl4;
|
|
|
|
if (ip_tunnel_info_af(info) != AF_INET)
|
|
return -EINVAL;
|
|
|
|
rt = gre_get_rt(skb, dev, &fl4, &info->key);
|
|
if (IS_ERR(rt))
|
|
return PTR_ERR(rt);
|
|
|
|
ip_rt_put(rt);
|
|
info->key.u.ipv4.src = fl4.saddr;
|
|
return 0;
|
|
}
|
|
|
|
static netdev_tx_t ipgre_xmit(struct sk_buff *skb,
|
|
struct net_device *dev)
|
|
{
|
|
struct ip_tunnel *tunnel = netdev_priv(dev);
|
|
const struct iphdr *tnl_params;
|
|
|
|
if (tunnel->collect_md) {
|
|
gre_fb_xmit(skb, dev, skb->protocol);
|
|
return NETDEV_TX_OK;
|
|
}
|
|
|
|
if (dev->header_ops) {
|
|
/* Need space for new headers */
|
|
if (skb_cow_head(skb, dev->needed_headroom -
|
|
(tunnel->hlen + sizeof(struct iphdr))))
|
|
goto free_skb;
|
|
|
|
tnl_params = (const struct iphdr *)skb->data;
|
|
|
|
/* Pull skb since ip_tunnel_xmit() needs skb->data pointing
|
|
* to gre header.
|
|
*/
|
|
skb_pull(skb, tunnel->hlen + sizeof(struct iphdr));
|
|
skb_reset_mac_header(skb);
|
|
} else {
|
|
if (skb_cow_head(skb, dev->needed_headroom))
|
|
goto free_skb;
|
|
|
|
tnl_params = &tunnel->parms.iph;
|
|
}
|
|
|
|
if (gre_handle_offloads(skb, !!(tunnel->parms.o_flags & TUNNEL_CSUM)))
|
|
goto free_skb;
|
|
|
|
__gre_xmit(skb, dev, tnl_params, skb->protocol);
|
|
return NETDEV_TX_OK;
|
|
|
|
free_skb:
|
|
kfree_skb(skb);
|
|
dev->stats.tx_dropped++;
|
|
return NETDEV_TX_OK;
|
|
}
|
|
|
|
static inline u8 tos_to_cos(u8 tos)
|
|
{
|
|
u8 dscp, cos;
|
|
|
|
dscp = tos >> 2;
|
|
cos = dscp >> 3;
|
|
return cos;
|
|
}
|
|
|
|
static void erspan_build_header(struct sk_buff *skb,
|
|
__be32 id, u32 index, bool truncate)
|
|
{
|
|
struct iphdr *iphdr = ip_hdr(skb);
|
|
struct ethhdr *eth = eth_hdr(skb);
|
|
enum erspan_encap_type enc_type;
|
|
struct erspanhdr *ershdr;
|
|
struct qtag_prefix {
|
|
__be16 eth_type;
|
|
__be16 tci;
|
|
} *qp;
|
|
u16 vlan_tci = 0;
|
|
|
|
enc_type = ERSPAN_ENCAP_NOVLAN;
|
|
|
|
/* If mirrored packet has vlan tag, extract tci and
|
|
* perserve vlan header in the mirrored frame.
|
|
*/
|
|
if (eth->h_proto == htons(ETH_P_8021Q)) {
|
|
qp = (struct qtag_prefix *)(skb->data + 2 * ETH_ALEN);
|
|
vlan_tci = ntohs(qp->tci);
|
|
enc_type = ERSPAN_ENCAP_INFRAME;
|
|
}
|
|
|
|
skb_push(skb, sizeof(*ershdr));
|
|
ershdr = (struct erspanhdr *)skb->data;
|
|
memset(ershdr, 0, sizeof(*ershdr));
|
|
|
|
ershdr->ver_vlan = htons((vlan_tci & VLAN_MASK) |
|
|
(ERSPAN_VERSION << VER_OFFSET));
|
|
ershdr->session_id = htons((u16)(ntohl(id) & ID_MASK) |
|
|
((tos_to_cos(iphdr->tos) << COS_OFFSET) & COS_MASK) |
|
|
(enc_type << EN_OFFSET & EN_MASK) |
|
|
((truncate << T_OFFSET) & T_MASK));
|
|
ershdr->md.index = htonl(index & INDEX_MASK);
|
|
}
|
|
|
|
static netdev_tx_t erspan_xmit(struct sk_buff *skb,
|
|
struct net_device *dev)
|
|
{
|
|
struct ip_tunnel *tunnel = netdev_priv(dev);
|
|
bool truncate = false;
|
|
|
|
if (tunnel->collect_md) {
|
|
erspan_fb_xmit(skb, dev, skb->protocol);
|
|
return NETDEV_TX_OK;
|
|
}
|
|
|
|
if (gre_handle_offloads(skb, false))
|
|
goto free_skb;
|
|
|
|
if (skb_cow_head(skb, dev->needed_headroom))
|
|
goto free_skb;
|
|
|
|
if (skb->len > dev->mtu) {
|
|
pskb_trim(skb, dev->mtu);
|
|
truncate = true;
|
|
}
|
|
|
|
/* Push ERSPAN header */
|
|
erspan_build_header(skb, tunnel->parms.o_key, tunnel->index, truncate);
|
|
tunnel->parms.o_flags &= ~TUNNEL_KEY;
|
|
__gre_xmit(skb, dev, &tunnel->parms.iph, htons(ETH_P_ERSPAN));
|
|
return NETDEV_TX_OK;
|
|
|
|
free_skb:
|
|
kfree_skb(skb);
|
|
dev->stats.tx_dropped++;
|
|
return NETDEV_TX_OK;
|
|
}
|
|
|
|
static netdev_tx_t gre_tap_xmit(struct sk_buff *skb,
|
|
struct net_device *dev)
|
|
{
|
|
struct ip_tunnel *tunnel = netdev_priv(dev);
|
|
|
|
if (tunnel->collect_md) {
|
|
gre_fb_xmit(skb, dev, htons(ETH_P_TEB));
|
|
return NETDEV_TX_OK;
|
|
}
|
|
|
|
if (gre_handle_offloads(skb, !!(tunnel->parms.o_flags & TUNNEL_CSUM)))
|
|
goto free_skb;
|
|
|
|
if (skb_cow_head(skb, dev->needed_headroom))
|
|
goto free_skb;
|
|
|
|
__gre_xmit(skb, dev, &tunnel->parms.iph, htons(ETH_P_TEB));
|
|
return NETDEV_TX_OK;
|
|
|
|
free_skb:
|
|
kfree_skb(skb);
|
|
dev->stats.tx_dropped++;
|
|
return NETDEV_TX_OK;
|
|
}
|
|
|
|
static int ipgre_tunnel_ioctl(struct net_device *dev,
|
|
struct ifreq *ifr, int cmd)
|
|
{
|
|
int err;
|
|
struct ip_tunnel_parm p;
|
|
|
|
if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
|
|
return -EFAULT;
|
|
if (cmd == SIOCADDTUNNEL || cmd == SIOCCHGTUNNEL) {
|
|
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)))
|
|
return -EINVAL;
|
|
}
|
|
p.i_flags = gre_flags_to_tnl_flags(p.i_flags);
|
|
p.o_flags = gre_flags_to_tnl_flags(p.o_flags);
|
|
|
|
err = ip_tunnel_ioctl(dev, &p, cmd);
|
|
if (err)
|
|
return err;
|
|
|
|
p.i_flags = gre_tnl_flags_to_gre_flags(p.i_flags);
|
|
p.o_flags = gre_tnl_flags_to_gre_flags(p.o_flags);
|
|
|
|
if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
|
|
return -EFAULT;
|
|
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 gre_base_hdr *greh;
|
|
|
|
iph = skb_push(skb, t->hlen + sizeof(*iph));
|
|
greh = (struct gre_base_hdr *)(iph+1);
|
|
greh->flags = gre_tnl_flags_to_gre_flags(t->parms.o_flags);
|
|
greh->protocol = htons(type);
|
|
|
|
memcpy(iph, &t->parms.iph, sizeof(struct iphdr));
|
|
|
|
/* 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 + sizeof(*iph);
|
|
|
|
return -(t->hlen + sizeof(*iph));
|
|
}
|
|
|
|
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(t->net, &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))
|
|
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(t->net, 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 = ip_tunnel_uninit,
|
|
#ifdef CONFIG_NET_IPGRE_BROADCAST
|
|
.ndo_open = ipgre_open,
|
|
.ndo_stop = ipgre_close,
|
|
#endif
|
|
.ndo_start_xmit = ipgre_xmit,
|
|
.ndo_do_ioctl = ipgre_tunnel_ioctl,
|
|
.ndo_change_mtu = ip_tunnel_change_mtu,
|
|
.ndo_get_stats64 = ip_tunnel_get_stats64,
|
|
.ndo_get_iflink = ip_tunnel_get_iflink,
|
|
};
|
|
|
|
#define GRE_FEATURES (NETIF_F_SG | \
|
|
NETIF_F_FRAGLIST | \
|
|
NETIF_F_HIGHDMA | \
|
|
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;
|
|
int t_hlen;
|
|
|
|
tunnel = netdev_priv(dev);
|
|
tunnel->tun_hlen = gre_calc_hlen(tunnel->parms.o_flags);
|
|
tunnel->parms.iph.protocol = IPPROTO_GRE;
|
|
|
|
tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen;
|
|
|
|
t_hlen = tunnel->hlen + sizeof(struct iphdr);
|
|
|
|
dev->needed_headroom = LL_MAX_HEADER + t_hlen + 4;
|
|
dev->mtu = ETH_DATA_LEN - t_hlen - 4;
|
|
|
|
dev->features |= GRE_FEATURES;
|
|
dev->hw_features |= GRE_FEATURES;
|
|
|
|
if (!(tunnel->parms.o_flags & TUNNEL_SEQ)) {
|
|
/* TCP offload with GRE SEQ is not supported, nor
|
|
* can we support 2 levels of outer headers requiring
|
|
* an update.
|
|
*/
|
|
if (!(tunnel->parms.o_flags & TUNNEL_CSUM) ||
|
|
(tunnel->encap.type == TUNNEL_ENCAP_NONE)) {
|
|
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;
|
|
netif_keep_dst(dev);
|
|
dev->addr_len = 4;
|
|
|
|
if (iph->daddr && !tunnel->collect_md) {
|
|
#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 if (!tunnel->collect_md) {
|
|
dev->header_ops = &ipgre_header_ops;
|
|
}
|
|
|
|
return ip_tunnel_init(dev);
|
|
}
|
|
|
|
static const struct gre_protocol ipgre_protocol = {
|
|
.handler = gre_rcv,
|
|
.err_handler = gre_err,
|
|
};
|
|
|
|
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[],
|
|
struct netlink_ext_ack *extack)
|
|
{
|
|
__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;
|
|
|
|
if (data[IFLA_GRE_COLLECT_METADATA] &&
|
|
data[IFLA_GRE_ENCAP_TYPE] &&
|
|
nla_get_u16(data[IFLA_GRE_ENCAP_TYPE]) != TUNNEL_ENCAP_NONE)
|
|
return -EINVAL;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int ipgre_tap_validate(struct nlattr *tb[], struct nlattr *data[],
|
|
struct netlink_ext_ack *extack)
|
|
{
|
|
__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, extack);
|
|
}
|
|
|
|
static int erspan_validate(struct nlattr *tb[], struct nlattr *data[],
|
|
struct netlink_ext_ack *extack)
|
|
{
|
|
__be16 flags = 0;
|
|
int ret;
|
|
|
|
if (!data)
|
|
return 0;
|
|
|
|
ret = ipgre_tap_validate(tb, data, extack);
|
|
if (ret)
|
|
return ret;
|
|
|
|
/* ERSPAN should only have GRE sequence and key flag */
|
|
if (data[IFLA_GRE_OFLAGS])
|
|
flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]);
|
|
if (data[IFLA_GRE_IFLAGS])
|
|
flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]);
|
|
if (!data[IFLA_GRE_COLLECT_METADATA] &&
|
|
flags != (GRE_SEQ | GRE_KEY))
|
|
return -EINVAL;
|
|
|
|
/* ERSPAN Session ID only has 10-bit. Since we reuse
|
|
* 32-bit key field as ID, check it's range.
|
|
*/
|
|
if (data[IFLA_GRE_IKEY] &&
|
|
(ntohl(nla_get_be32(data[IFLA_GRE_IKEY])) & ~ID_MASK))
|
|
return -EINVAL;
|
|
|
|
if (data[IFLA_GRE_OKEY] &&
|
|
(ntohl(nla_get_be32(data[IFLA_GRE_OKEY])) & ~ID_MASK))
|
|
return -EINVAL;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int ipgre_netlink_parms(struct net_device *dev,
|
|
struct nlattr *data[],
|
|
struct nlattr *tb[],
|
|
struct ip_tunnel_parm *parms,
|
|
__u32 *fwmark)
|
|
{
|
|
struct ip_tunnel *t = netdev_priv(dev);
|
|
|
|
memset(parms, 0, sizeof(*parms));
|
|
|
|
parms->iph.protocol = IPPROTO_GRE;
|
|
|
|
if (!data)
|
|
return 0;
|
|
|
|
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_in_addr(data[IFLA_GRE_LOCAL]);
|
|
|
|
if (data[IFLA_GRE_REMOTE])
|
|
parms->iph.daddr = nla_get_in_addr(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])) {
|
|
if (t->ignore_df)
|
|
return -EINVAL;
|
|
parms->iph.frag_off = htons(IP_DF);
|
|
}
|
|
|
|
if (data[IFLA_GRE_COLLECT_METADATA]) {
|
|
t->collect_md = true;
|
|
if (dev->type == ARPHRD_IPGRE)
|
|
dev->type = ARPHRD_NONE;
|
|
}
|
|
|
|
if (data[IFLA_GRE_IGNORE_DF]) {
|
|
if (nla_get_u8(data[IFLA_GRE_IGNORE_DF])
|
|
&& (parms->iph.frag_off & htons(IP_DF)))
|
|
return -EINVAL;
|
|
t->ignore_df = !!nla_get_u8(data[IFLA_GRE_IGNORE_DF]);
|
|
}
|
|
|
|
if (data[IFLA_GRE_FWMARK])
|
|
*fwmark = nla_get_u32(data[IFLA_GRE_FWMARK]);
|
|
|
|
if (data[IFLA_GRE_ERSPAN_INDEX]) {
|
|
t->index = nla_get_u32(data[IFLA_GRE_ERSPAN_INDEX]);
|
|
|
|
if (t->index & ~INDEX_MASK)
|
|
return -EINVAL;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* This function returns true when ENCAP attributes are present in the nl msg */
|
|
static bool ipgre_netlink_encap_parms(struct nlattr *data[],
|
|
struct ip_tunnel_encap *ipencap)
|
|
{
|
|
bool ret = false;
|
|
|
|
memset(ipencap, 0, sizeof(*ipencap));
|
|
|
|
if (!data)
|
|
return ret;
|
|
|
|
if (data[IFLA_GRE_ENCAP_TYPE]) {
|
|
ret = true;
|
|
ipencap->type = nla_get_u16(data[IFLA_GRE_ENCAP_TYPE]);
|
|
}
|
|
|
|
if (data[IFLA_GRE_ENCAP_FLAGS]) {
|
|
ret = true;
|
|
ipencap->flags = nla_get_u16(data[IFLA_GRE_ENCAP_FLAGS]);
|
|
}
|
|
|
|
if (data[IFLA_GRE_ENCAP_SPORT]) {
|
|
ret = true;
|
|
ipencap->sport = nla_get_be16(data[IFLA_GRE_ENCAP_SPORT]);
|
|
}
|
|
|
|
if (data[IFLA_GRE_ENCAP_DPORT]) {
|
|
ret = true;
|
|
ipencap->dport = nla_get_be16(data[IFLA_GRE_ENCAP_DPORT]);
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int gre_tap_init(struct net_device *dev)
|
|
{
|
|
__gre_tunnel_init(dev);
|
|
dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
|
|
|
|
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,
|
|
.ndo_get_iflink = ip_tunnel_get_iflink,
|
|
.ndo_fill_metadata_dst = gre_fill_metadata_dst,
|
|
};
|
|
|
|
static int erspan_tunnel_init(struct net_device *dev)
|
|
{
|
|
struct ip_tunnel *tunnel = netdev_priv(dev);
|
|
int t_hlen;
|
|
|
|
tunnel->tun_hlen = 8;
|
|
tunnel->parms.iph.protocol = IPPROTO_GRE;
|
|
t_hlen = tunnel->hlen + sizeof(struct iphdr) + sizeof(struct erspanhdr);
|
|
|
|
dev->needed_headroom = LL_MAX_HEADER + t_hlen + 4;
|
|
dev->mtu = ETH_DATA_LEN - t_hlen - 4;
|
|
dev->features |= GRE_FEATURES;
|
|
dev->hw_features |= GRE_FEATURES;
|
|
dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
|
|
|
|
return ip_tunnel_init(dev);
|
|
}
|
|
|
|
static const struct net_device_ops erspan_netdev_ops = {
|
|
.ndo_init = erspan_tunnel_init,
|
|
.ndo_uninit = ip_tunnel_uninit,
|
|
.ndo_start_xmit = erspan_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,
|
|
.ndo_get_iflink = ip_tunnel_get_iflink,
|
|
.ndo_fill_metadata_dst = gre_fill_metadata_dst,
|
|
};
|
|
|
|
static void ipgre_tap_setup(struct net_device *dev)
|
|
{
|
|
ether_setup(dev);
|
|
dev->netdev_ops = &gre_tap_netdev_ops;
|
|
dev->priv_flags &= ~IFF_TX_SKB_SHARING;
|
|
dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
|
|
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 netlink_ext_ack *extack)
|
|
{
|
|
struct ip_tunnel_parm p;
|
|
struct ip_tunnel_encap ipencap;
|
|
__u32 fwmark = 0;
|
|
int err;
|
|
|
|
if (ipgre_netlink_encap_parms(data, &ipencap)) {
|
|
struct ip_tunnel *t = netdev_priv(dev);
|
|
err = ip_tunnel_encap_setup(t, &ipencap);
|
|
|
|
if (err < 0)
|
|
return err;
|
|
}
|
|
|
|
err = ipgre_netlink_parms(dev, data, tb, &p, &fwmark);
|
|
if (err < 0)
|
|
return err;
|
|
return ip_tunnel_newlink(dev, tb, &p, fwmark);
|
|
}
|
|
|
|
static int ipgre_changelink(struct net_device *dev, struct nlattr *tb[],
|
|
struct nlattr *data[],
|
|
struct netlink_ext_ack *extack)
|
|
{
|
|
struct ip_tunnel *t = netdev_priv(dev);
|
|
struct ip_tunnel_parm p;
|
|
struct ip_tunnel_encap ipencap;
|
|
__u32 fwmark = t->fwmark;
|
|
int err;
|
|
|
|
if (ipgre_netlink_encap_parms(data, &ipencap)) {
|
|
err = ip_tunnel_encap_setup(t, &ipencap);
|
|
|
|
if (err < 0)
|
|
return err;
|
|
}
|
|
|
|
err = ipgre_netlink_parms(dev, data, tb, &p, &fwmark);
|
|
if (err < 0)
|
|
return err;
|
|
return ip_tunnel_changelink(dev, tb, &p, fwmark);
|
|
}
|
|
|
|
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) +
|
|
/* IFLA_GRE_ENCAP_TYPE */
|
|
nla_total_size(2) +
|
|
/* IFLA_GRE_ENCAP_FLAGS */
|
|
nla_total_size(2) +
|
|
/* IFLA_GRE_ENCAP_SPORT */
|
|
nla_total_size(2) +
|
|
/* IFLA_GRE_ENCAP_DPORT */
|
|
nla_total_size(2) +
|
|
/* IFLA_GRE_COLLECT_METADATA */
|
|
nla_total_size(0) +
|
|
/* IFLA_GRE_IGNORE_DF */
|
|
nla_total_size(1) +
|
|
/* IFLA_GRE_FWMARK */
|
|
nla_total_size(4) +
|
|
/* IFLA_GRE_ERSPAN_INDEX */
|
|
nla_total_size(4) +
|
|
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,
|
|
gre_tnl_flags_to_gre_flags(p->i_flags)) ||
|
|
nla_put_be16(skb, IFLA_GRE_OFLAGS,
|
|
gre_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_in_addr(skb, IFLA_GRE_LOCAL, p->iph.saddr) ||
|
|
nla_put_in_addr(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))) ||
|
|
nla_put_u32(skb, IFLA_GRE_FWMARK, t->fwmark))
|
|
goto nla_put_failure;
|
|
|
|
if (nla_put_u16(skb, IFLA_GRE_ENCAP_TYPE,
|
|
t->encap.type) ||
|
|
nla_put_be16(skb, IFLA_GRE_ENCAP_SPORT,
|
|
t->encap.sport) ||
|
|
nla_put_be16(skb, IFLA_GRE_ENCAP_DPORT,
|
|
t->encap.dport) ||
|
|
nla_put_u16(skb, IFLA_GRE_ENCAP_FLAGS,
|
|
t->encap.flags))
|
|
goto nla_put_failure;
|
|
|
|
if (nla_put_u8(skb, IFLA_GRE_IGNORE_DF, t->ignore_df))
|
|
goto nla_put_failure;
|
|
|
|
if (t->collect_md) {
|
|
if (nla_put_flag(skb, IFLA_GRE_COLLECT_METADATA))
|
|
goto nla_put_failure;
|
|
}
|
|
|
|
if (t->index)
|
|
if (nla_put_u32(skb, IFLA_GRE_ERSPAN_INDEX, t->index))
|
|
goto nla_put_failure;
|
|
|
|
return 0;
|
|
|
|
nla_put_failure:
|
|
return -EMSGSIZE;
|
|
}
|
|
|
|
static void erspan_setup(struct net_device *dev)
|
|
{
|
|
ether_setup(dev);
|
|
dev->netdev_ops = &erspan_netdev_ops;
|
|
dev->priv_flags &= ~IFF_TX_SKB_SHARING;
|
|
dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
|
|
ip_tunnel_setup(dev, erspan_net_id);
|
|
}
|
|
|
|
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 },
|
|
[IFLA_GRE_ENCAP_TYPE] = { .type = NLA_U16 },
|
|
[IFLA_GRE_ENCAP_FLAGS] = { .type = NLA_U16 },
|
|
[IFLA_GRE_ENCAP_SPORT] = { .type = NLA_U16 },
|
|
[IFLA_GRE_ENCAP_DPORT] = { .type = NLA_U16 },
|
|
[IFLA_GRE_COLLECT_METADATA] = { .type = NLA_FLAG },
|
|
[IFLA_GRE_IGNORE_DF] = { .type = NLA_U8 },
|
|
[IFLA_GRE_FWMARK] = { .type = NLA_U32 },
|
|
[IFLA_GRE_ERSPAN_INDEX] = { .type = NLA_U32 },
|
|
};
|
|
|
|
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,
|
|
.get_link_net = ip_tunnel_get_link_net,
|
|
};
|
|
|
|
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,
|
|
.get_link_net = ip_tunnel_get_link_net,
|
|
};
|
|
|
|
static struct rtnl_link_ops erspan_link_ops __read_mostly = {
|
|
.kind = "erspan",
|
|
.maxtype = IFLA_GRE_MAX,
|
|
.policy = ipgre_policy,
|
|
.priv_size = sizeof(struct ip_tunnel),
|
|
.setup = erspan_setup,
|
|
.validate = erspan_validate,
|
|
.newlink = ipgre_newlink,
|
|
.changelink = ipgre_changelink,
|
|
.dellink = ip_tunnel_dellink,
|
|
.get_size = ipgre_get_size,
|
|
.fill_info = ipgre_fill_info,
|
|
.get_link_net = ip_tunnel_get_link_net,
|
|
};
|
|
|
|
struct net_device *gretap_fb_dev_create(struct net *net, const char *name,
|
|
u8 name_assign_type)
|
|
{
|
|
struct nlattr *tb[IFLA_MAX + 1];
|
|
struct net_device *dev;
|
|
LIST_HEAD(list_kill);
|
|
struct ip_tunnel *t;
|
|
int err;
|
|
|
|
memset(&tb, 0, sizeof(tb));
|
|
|
|
dev = rtnl_create_link(net, name, name_assign_type,
|
|
&ipgre_tap_ops, tb);
|
|
if (IS_ERR(dev))
|
|
return dev;
|
|
|
|
/* Configure flow based GRE device. */
|
|
t = netdev_priv(dev);
|
|
t->collect_md = true;
|
|
|
|
err = ipgre_newlink(net, dev, tb, NULL, NULL);
|
|
if (err < 0) {
|
|
free_netdev(dev);
|
|
return ERR_PTR(err);
|
|
}
|
|
|
|
/* openvswitch users expect packet sizes to be unrestricted,
|
|
* so set the largest MTU we can.
|
|
*/
|
|
err = __ip_tunnel_change_mtu(dev, IP_MAX_MTU, false);
|
|
if (err)
|
|
goto out;
|
|
|
|
err = rtnl_configure_link(dev, NULL);
|
|
if (err < 0)
|
|
goto out;
|
|
|
|
return dev;
|
|
out:
|
|
ip_tunnel_dellink(dev, &list_kill);
|
|
unregister_netdevice_many(&list_kill);
|
|
return ERR_PTR(err);
|
|
}
|
|
EXPORT_SYMBOL_GPL(gretap_fb_dev_create);
|
|
|
|
static int __net_init ipgre_tap_init_net(struct net *net)
|
|
{
|
|
return ip_tunnel_init_net(net, gre_tap_net_id, &ipgre_tap_ops, "gretap0");
|
|
}
|
|
|
|
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 __net_init erspan_init_net(struct net *net)
|
|
{
|
|
return ip_tunnel_init_net(net, erspan_net_id,
|
|
&erspan_link_ops, "erspan0");
|
|
}
|
|
|
|
static void __net_exit erspan_exit_net(struct net *net)
|
|
{
|
|
struct ip_tunnel_net *itn = net_generic(net, erspan_net_id);
|
|
|
|
ip_tunnel_delete_net(itn, &erspan_link_ops);
|
|
}
|
|
|
|
static struct pernet_operations erspan_net_ops = {
|
|
.init = erspan_init_net,
|
|
.exit = erspan_exit_net,
|
|
.id = &erspan_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_failed;
|
|
|
|
err = register_pernet_device(&erspan_net_ops);
|
|
if (err < 0)
|
|
goto pnet_erspan_failed;
|
|
|
|
err = gre_add_protocol(&ipgre_protocol, GREPROTO_CISCO);
|
|
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;
|
|
|
|
err = rtnl_link_register(&erspan_link_ops);
|
|
if (err < 0)
|
|
goto erspan_link_failed;
|
|
|
|
return 0;
|
|
|
|
erspan_link_failed:
|
|
rtnl_link_unregister(&ipgre_tap_ops);
|
|
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(&erspan_net_ops);
|
|
pnet_erspan_failed:
|
|
unregister_pernet_device(&ipgre_tap_net_ops);
|
|
pnet_tap_failed:
|
|
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);
|
|
rtnl_link_unregister(&erspan_link_ops);
|
|
gre_del_protocol(&ipgre_protocol, GREPROTO_CISCO);
|
|
unregister_pernet_device(&ipgre_tap_net_ops);
|
|
unregister_pernet_device(&ipgre_net_ops);
|
|
unregister_pernet_device(&erspan_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_RTNL_LINK("erspan");
|
|
MODULE_ALIAS_NETDEV("gre0");
|
|
MODULE_ALIAS_NETDEV("gretap0");
|
|
MODULE_ALIAS_NETDEV("erspan0");
|