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-rw-r--r--net/ipv4/ip_gre.c926
1 files changed, 926 insertions, 0 deletions
diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c
new file mode 100644
index 000000000..5fd706473
--- /dev/null
+++ b/net/ipv4/ip_gre.c
@@ -0,0 +1,926 @@
+/*
+ * Linux NET3: GRE over IP protocol decoder.
+ *
+ * Authors: Alexey Kuznetsov (kuznet@ms2.inr.ac.ru)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ *
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/capability.h>
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <asm/uaccess.h>
+#include <linux/skbuff.h>
+#include <linux/netdevice.h>
+#include <linux/in.h>
+#include <linux/tcp.h>
+#include <linux/udp.h>
+#include <linux/if_arp.h>
+#include <linux/mroute.h>
+#include <linux/init.h>
+#include <linux/in6.h>
+#include <linux/inetdevice.h>
+#include <linux/igmp.h>
+#include <linux/netfilter_ipv4.h>
+#include <linux/etherdevice.h>
+#include <linux/if_ether.h>
+
+#include <net/sock.h>
+#include <net/ip.h>
+#include <net/icmp.h>
+#include <net/protocol.h>
+#include <net/ip_tunnels.h>
+#include <net/arp.h>
+#include <net/checksum.h>
+#include <net/dsfield.h>
+#include <net/inet_ecn.h>
+#include <net/xfrm.h>
+#include <net/net_namespace.h>
+#include <net/netns/generic.h>
+#include <net/rtnetlink.h>
+#include <net/gre.h>
+
+#if IS_ENABLED(CONFIG_IPV6)
+#include <net/ipv6.h>
+#include <net/ip6_fib.h>
+#include <net/ip6_route.h>
+#endif
+
+/*
+ Problems & solutions
+ --------------------
+
+ 1. The most important issue is detecting local dead loops.
+ They would cause complete host lockup in transmit, which
+ would be "resolved" by stack overflow or, if queueing is enabled,
+ with infinite looping in net_bh.
+
+ We cannot track such dead loops during route installation,
+ it is infeasible task. The most general solutions would be
+ to keep skb->encapsulation counter (sort of local ttl),
+ and silently drop packet when it expires. It is a good
+ solution, but it supposes maintaining new variable in ALL
+ skb, even if no tunneling is used.
+
+ Current solution: xmit_recursion breaks dead loops. This is a percpu
+ counter, since when we enter the first ndo_xmit(), cpu migration is
+ forbidden. We force an exit if this counter reaches RECURSION_LIMIT
+
+ 2. Networking dead loops would not kill routers, but would really
+ kill network. IP hop limit plays role of "t->recursion" in this case,
+ if we copy it from packet being encapsulated to upper header.
+ It is very good solution, but it introduces two problems:
+
+ - Routing protocols, using packets with ttl=1 (OSPF, RIP2),
+ do not work over tunnels.
+ - traceroute does not work. I planned to relay ICMP from tunnel,
+ so that this problem would be solved and traceroute output
+ would even more informative. This idea appeared to be wrong:
+ only Linux complies to rfc1812 now (yes, guys, Linux is the only
+ true router now :-)), all routers (at least, in neighbourhood of mine)
+ return only 8 bytes of payload. It is the end.
+
+ Hence, if we want that OSPF worked or traceroute said something reasonable,
+ we should search for another solution.
+
+ One of them is to parse packet trying to detect inner encapsulation
+ made by our node. It is difficult or even impossible, especially,
+ taking into account fragmentation. TO be short, ttl is not solution at all.
+
+ Current solution: The solution was UNEXPECTEDLY SIMPLE.
+ We force DF flag on tunnels with preconfigured hop limit,
+ that is ALL. :-) Well, it does not remove the problem completely,
+ but exponential growth of network traffic is changed to linear
+ (branches, that exceed pmtu are pruned) and tunnel mtu
+ rapidly degrades to value <68, where looping stops.
+ Yes, it is not good if there exists a router in the loop,
+ which does not force DF, even when encapsulating packets have DF set.
+ But it is not our problem! Nobody could accuse us, we made
+ all that we could make. Even if it is your gated who injected
+ fatal route to network, even if it were you who configured
+ fatal static route: you are innocent. :-)
+
+ Alexey Kuznetsov.
+ */
+
+static bool log_ecn_error = true;
+module_param(log_ecn_error, bool, 0644);
+MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN");
+
+static struct rtnl_link_ops ipgre_link_ops __read_mostly;
+static int ipgre_tunnel_init(struct net_device *dev);
+
+static int ipgre_net_id __read_mostly;
+static int gre_tap_net_id __read_mostly;
+
+static int ipgre_err(struct sk_buff *skb, u32 info,
+ const struct tnl_ptk_info *tpi)
+{
+
+ /* All the routers (except for Linux) return only
+ 8 bytes of packet payload. It means, that precise relaying of
+ ICMP in the real Internet is absolutely infeasible.
+
+ Moreover, Cisco "wise men" put GRE key to the third word
+ in GRE header. It makes impossible maintaining even soft
+ state for keyed GRE tunnels with enabled checksum. Tell
+ them "thank you".
+
+ Well, I wonder, rfc1812 was written by Cisco employee,
+ what the hell these idiots break standards established
+ by themselves???
+ */
+ struct net *net = dev_net(skb->dev);
+ struct ip_tunnel_net *itn;
+ const struct iphdr *iph;
+ const int type = icmp_hdr(skb)->type;
+ const int code = icmp_hdr(skb)->code;
+ struct ip_tunnel *t;
+
+ switch (type) {
+ default:
+ case ICMP_PARAMETERPROB:
+ return PACKET_RCVD;
+
+ case ICMP_DEST_UNREACH:
+ switch (code) {
+ case ICMP_SR_FAILED:
+ case ICMP_PORT_UNREACH:
+ /* Impossible event. */
+ return PACKET_RCVD;
+ default:
+ /* All others are translated to HOST_UNREACH.
+ rfc2003 contains "deep thoughts" about NET_UNREACH,
+ I believe they are just ether pollution. --ANK
+ */
+ break;
+ }
+ break;
+ case ICMP_TIME_EXCEEDED:
+ if (code != ICMP_EXC_TTL)
+ return PACKET_RCVD;
+ break;
+
+ case ICMP_REDIRECT:
+ break;
+ }
+
+ if (tpi->proto == htons(ETH_P_TEB))
+ itn = net_generic(net, gre_tap_net_id);
+ else
+ itn = net_generic(net, ipgre_net_id);
+
+ iph = (const struct iphdr *)(icmp_hdr(skb) + 1);
+ t = ip_tunnel_lookup(itn, skb->dev->ifindex, tpi->flags,
+ iph->daddr, iph->saddr, tpi->key);
+
+ if (!t)
+ return PACKET_REJECT;
+
+ if (t->parms.iph.daddr == 0 ||
+ ipv4_is_multicast(t->parms.iph.daddr))
+ return PACKET_RCVD;
+
+ if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED)
+ return PACKET_RCVD;
+
+ if (time_before(jiffies, t->err_time + IPTUNNEL_ERR_TIMEO))
+ t->err_count++;
+ else
+ t->err_count = 1;
+ t->err_time = jiffies;
+ return PACKET_RCVD;
+}
+
+static int ipgre_rcv(struct sk_buff *skb, const struct tnl_ptk_info *tpi)
+{
+ struct net *net = dev_net(skb->dev);
+ struct ip_tunnel_net *itn;
+ const struct iphdr *iph;
+ struct ip_tunnel *tunnel;
+
+ if (tpi->proto == htons(ETH_P_TEB))
+ itn = net_generic(net, gre_tap_net_id);
+ else
+ itn = net_generic(net, ipgre_net_id);
+
+ iph = ip_hdr(skb);
+ tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex, tpi->flags,
+ iph->saddr, iph->daddr, tpi->key);
+
+ if (tunnel) {
+ skb_pop_mac_header(skb);
+ ip_tunnel_rcv(tunnel, skb, tpi, log_ecn_error);
+ return PACKET_RCVD;
+ }
+ return PACKET_REJECT;
+}
+
+static void __gre_xmit(struct sk_buff *skb, struct net_device *dev,
+ const struct iphdr *tnl_params,
+ __be16 proto)
+{
+ struct ip_tunnel *tunnel = netdev_priv(dev);
+ struct tnl_ptk_info tpi;
+
+ tpi.flags = tunnel->parms.o_flags;
+ tpi.proto = proto;
+ tpi.key = tunnel->parms.o_key;
+ if (tunnel->parms.o_flags & TUNNEL_SEQ)
+ tunnel->o_seqno++;
+ tpi.seq = htonl(tunnel->o_seqno);
+
+ /* Push GRE header. */
+ gre_build_header(skb, &tpi, tunnel->tun_hlen);
+
+ skb_set_inner_protocol(skb, tpi.proto);
+
+ ip_tunnel_xmit(skb, dev, tnl_params, tnl_params->protocol);
+}
+
+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 (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;
+ }
+
+ skb = gre_handle_offloads(skb, !!(tunnel->parms.o_flags&TUNNEL_CSUM));
+ if (IS_ERR(skb))
+ goto out;
+
+ __gre_xmit(skb, dev, tnl_params, skb->protocol);
+
+ return NETDEV_TX_OK;
+
+free_skb:
+ kfree_skb(skb);
+out:
+ 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);
+
+ skb = gre_handle_offloads(skb, !!(tunnel->parms.o_flags&TUNNEL_CSUM));
+ if (IS_ERR(skb))
+ goto out;
+
+ 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);
+out:
+ 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 = tnl_flags_to_gre_flags(p.i_flags);
+ p.o_flags = 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 = (struct iphdr *)skb_push(skb, t->hlen + sizeof(*iph));
+ greh = (struct gre_base_hdr *)(iph+1);
+ greh->flags = 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 = ip_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. */
+ 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) {
+#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_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]))
+ parms->iph.frag_off = htons(IP_DF);
+}
+
+/* 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,
+};
+
+static void ipgre_tap_setup(struct net_device *dev)
+{
+ ether_setup(dev);
+ dev->netdev_ops = &gre_tap_netdev_ops;
+ 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 ip_tunnel_parm p;
+ struct ip_tunnel_encap ipencap;
+
+ if (ipgre_netlink_encap_parms(data, &ipencap)) {
+ struct ip_tunnel *t = netdev_priv(dev);
+ int err = ip_tunnel_encap_setup(t, &ipencap);
+
+ if (err < 0)
+ return err;
+ }
+
+ 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;
+ struct ip_tunnel_encap ipencap;
+
+ if (ipgre_netlink_encap_parms(data, &ipencap)) {
+ struct ip_tunnel *t = netdev_priv(dev);
+ int err = ip_tunnel_encap_setup(t, &ipencap);
+
+ if (err < 0)
+ return err;
+ }
+
+ 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) +
+ /* 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) +
+ 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_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))))
+ 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;
+
+ 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 },
+ [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 },
+};
+
+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 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");
generated by cgit v1.2.3-54-g00ecf (git 2.45.2) at 2024-07-03 23:18:20 +0000