GRE: Refactor GRE tunneling code.
Following patch refactors GRE code into ip tunneling code and GRE
specific code. Common tunneling code is moved to ip_tunnel module.
ip_tunnel module is written as generic library which can be used
by different tunneling implementations.
ip_tunnel module contains following components:
- packet xmit and rcv generic code. xmit flow looks like
(gre_xmit/ipip_xmit)->ip_tunnel_xmit->ip_local_out.
- hash table of all devices.
- lookup for tunnel devices.
- control plane operations like device create, destroy, ioctl, netlink
operations code.
- registration for tunneling modules, like gre, ipip etc.
- define single pcpu_tstats dev->tstats.
- struct tnl_ptk_info added to pass parsed tunnel packet parameters.
ipip.h header is renamed to ip_tunnel.h
Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/ip_tunnel.c b/net/ipv4/ip_tunnel.c
new file mode 100644
index 0000000..9d96b68
--- /dev/null
+++ b/net/ipv4/ip_tunnel.c
@@ -0,0 +1,1035 @@
+/*
+ * Copyright (c) 2013 Nicira, Inc.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA
+ */
+
+#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 <linux/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 <linux/if_vlan.h>
+#include <linux/rculist.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>
+
+#if IS_ENABLED(CONFIG_IPV6)
+#include <net/ipv6.h>
+#include <net/ip6_fib.h>
+#include <net/ip6_route.h>
+#endif
+
+static unsigned int ip_tunnel_hash(struct ip_tunnel_net *itn,
+ __be32 key, __be32 remote)
+{
+ return hash_32((__force u32)key ^ (__force u32)remote,
+ IP_TNL_HASH_BITS);
+}
+
+/* Often modified stats are per cpu, other are shared (netdev->stats) */
+struct rtnl_link_stats64 *ip_tunnel_get_stats64(struct net_device *dev,
+ struct rtnl_link_stats64 *tot)
+{
+ int i;
+
+ for_each_possible_cpu(i) {
+ const struct pcpu_tstats *tstats = per_cpu_ptr(dev->tstats, i);
+ u64 rx_packets, rx_bytes, tx_packets, tx_bytes;
+ unsigned int start;
+
+ do {
+ start = u64_stats_fetch_begin_bh(&tstats->syncp);
+ rx_packets = tstats->rx_packets;
+ tx_packets = tstats->tx_packets;
+ rx_bytes = tstats->rx_bytes;
+ tx_bytes = tstats->tx_bytes;
+ } while (u64_stats_fetch_retry_bh(&tstats->syncp, start));
+
+ tot->rx_packets += rx_packets;
+ tot->tx_packets += tx_packets;
+ tot->rx_bytes += rx_bytes;
+ tot->tx_bytes += tx_bytes;
+ }
+
+ tot->multicast = dev->stats.multicast;
+
+ tot->rx_crc_errors = dev->stats.rx_crc_errors;
+ tot->rx_fifo_errors = dev->stats.rx_fifo_errors;
+ tot->rx_length_errors = dev->stats.rx_length_errors;
+ tot->rx_frame_errors = dev->stats.rx_frame_errors;
+ tot->rx_errors = dev->stats.rx_errors;
+
+ tot->tx_fifo_errors = dev->stats.tx_fifo_errors;
+ tot->tx_carrier_errors = dev->stats.tx_carrier_errors;
+ tot->tx_dropped = dev->stats.tx_dropped;
+ tot->tx_aborted_errors = dev->stats.tx_aborted_errors;
+ tot->tx_errors = dev->stats.tx_errors;
+
+ tot->collisions = dev->stats.collisions;
+
+ return tot;
+}
+EXPORT_SYMBOL_GPL(ip_tunnel_get_stats64);
+
+static bool ip_tunnel_key_match(const struct ip_tunnel_parm *p,
+ __be16 flags, __be32 key)
+{
+ if (p->i_flags & TUNNEL_KEY) {
+ if (flags & TUNNEL_KEY)
+ return key == p->i_key;
+ else
+ /* key expected, none present */
+ return false;
+ } else
+ return !(flags & TUNNEL_KEY);
+}
+
+/* Fallback tunnel: no source, no destination, no key, no options
+
+ Tunnel hash table:
+ We require exact key match i.e. if a key is present in packet
+ it will match only tunnel with the same key; if it is not present,
+ it will match only keyless tunnel.
+
+ All keysless packets, if not matched configured keyless tunnels
+ will match fallback tunnel.
+ Given src, dst and key, find appropriate for input tunnel.
+*/
+struct ip_tunnel *ip_tunnel_lookup(struct ip_tunnel_net *itn,
+ int link, __be16 flags,
+ __be32 remote, __be32 local,
+ __be32 key)
+{
+ unsigned int hash;
+ struct ip_tunnel *t, *cand = NULL;
+ struct hlist_head *head;
+
+ hash = ip_tunnel_hash(itn, key, remote);
+ head = &itn->tunnels[hash];
+
+ hlist_for_each_entry_rcu(t, head, hash_node) {
+ if (local != t->parms.iph.saddr ||
+ remote != t->parms.iph.daddr ||
+ !(t->dev->flags & IFF_UP))
+ continue;
+
+ if (!ip_tunnel_key_match(&t->parms, flags, key))
+ continue;
+
+ if (t->parms.link == link)
+ return t;
+ else
+ cand = t;
+ }
+
+ hlist_for_each_entry_rcu(t, head, hash_node) {
+ if (remote != t->parms.iph.daddr ||
+ !(t->dev->flags & IFF_UP))
+ continue;
+
+ if (!ip_tunnel_key_match(&t->parms, flags, key))
+ continue;
+
+ if (t->parms.link == link)
+ return t;
+ else if (!cand)
+ cand = t;
+ }
+
+ hash = ip_tunnel_hash(itn, key, 0);
+ head = &itn->tunnels[hash];
+
+ hlist_for_each_entry_rcu(t, head, hash_node) {
+ if ((local != t->parms.iph.saddr &&
+ (local != t->parms.iph.daddr ||
+ !ipv4_is_multicast(local))) ||
+ !(t->dev->flags & IFF_UP))
+ continue;
+
+ if (!ip_tunnel_key_match(&t->parms, flags, key))
+ continue;
+
+ if (t->parms.link == link)
+ return t;
+ else if (!cand)
+ cand = t;
+ }
+
+ if (flags & TUNNEL_NO_KEY)
+ goto skip_key_lookup;
+
+ hlist_for_each_entry_rcu(t, head, hash_node) {
+ if (t->parms.i_key != key ||
+ !(t->dev->flags & IFF_UP))
+ continue;
+
+ if (t->parms.link == link)
+ return t;
+ else if (!cand)
+ cand = t;
+ }
+
+skip_key_lookup:
+ if (cand)
+ return cand;
+
+ if (itn->fb_tunnel_dev && itn->fb_tunnel_dev->flags & IFF_UP)
+ return netdev_priv(itn->fb_tunnel_dev);
+
+
+ return NULL;
+}
+EXPORT_SYMBOL_GPL(ip_tunnel_lookup);
+
+static struct hlist_head *ip_bucket(struct ip_tunnel_net *itn,
+ struct ip_tunnel_parm *parms)
+{
+ unsigned int h;
+ __be32 remote;
+
+ if (parms->iph.daddr && !ipv4_is_multicast(parms->iph.daddr))
+ remote = parms->iph.daddr;
+ else
+ remote = 0;
+
+ h = ip_tunnel_hash(itn, parms->i_key, remote);
+ return &itn->tunnels[h];
+}
+
+static void ip_tunnel_add(struct ip_tunnel_net *itn, struct ip_tunnel *t)
+{
+ struct hlist_head *head = ip_bucket(itn, &t->parms);
+
+ hlist_add_head_rcu(&t->hash_node, head);
+}
+
+static void ip_tunnel_del(struct ip_tunnel *t)
+{
+ hlist_del_init_rcu(&t->hash_node);
+}
+
+static struct ip_tunnel *ip_tunnel_find(struct ip_tunnel_net *itn,
+ struct ip_tunnel_parm *parms,
+ int type)
+{
+ __be32 remote = parms->iph.daddr;
+ __be32 local = parms->iph.saddr;
+ __be32 key = parms->i_key;
+ int link = parms->link;
+ struct ip_tunnel *t = NULL;
+ struct hlist_head *head = ip_bucket(itn, parms);
+
+ hlist_for_each_entry_rcu(t, head, hash_node) {
+ if (local == t->parms.iph.saddr &&
+ remote == t->parms.iph.daddr &&
+ key == t->parms.i_key &&
+ link == t->parms.link &&
+ type == t->dev->type)
+ break;
+ }
+ return t;
+}
+
+static struct net_device *__ip_tunnel_create(struct net *net,
+ const struct rtnl_link_ops *ops,
+ struct ip_tunnel_parm *parms)
+{
+ int err;
+ struct ip_tunnel *tunnel;
+ struct net_device *dev;
+ char name[IFNAMSIZ];
+
+ if (parms->name[0])
+ strlcpy(name, parms->name, IFNAMSIZ);
+ else {
+ if (strlen(ops->kind) + 3 >= IFNAMSIZ) {
+ err = -E2BIG;
+ goto failed;
+ }
+ strlcpy(name, ops->kind, IFNAMSIZ);
+ strncat(name, "%d", 2);
+ }
+
+ ASSERT_RTNL();
+ dev = alloc_netdev(ops->priv_size, name, ops->setup);
+ if (!dev) {
+ err = -ENOMEM;
+ goto failed;
+ }
+ dev_net_set(dev, net);
+
+ dev->rtnl_link_ops = ops;
+
+ tunnel = netdev_priv(dev);
+ tunnel->parms = *parms;
+
+ err = register_netdevice(dev);
+ if (err)
+ goto failed_free;
+
+ return dev;
+
+failed_free:
+ free_netdev(dev);
+failed:
+ return ERR_PTR(err);
+}
+
+static inline struct rtable *ip_route_output_tunnel(struct net *net,
+ struct flowi4 *fl4,
+ int proto,
+ __be32 daddr, __be32 saddr,
+ __be32 key, __u8 tos, int oif)
+{
+ memset(fl4, 0, sizeof(*fl4));
+ fl4->flowi4_oif = oif;
+ fl4->daddr = daddr;
+ fl4->saddr = saddr;
+ fl4->flowi4_tos = tos;
+ fl4->flowi4_proto = proto;
+ fl4->fl4_gre_key = key;
+ return ip_route_output_key(net, fl4);
+}
+
+static int ip_tunnel_bind_dev(struct net_device *dev)
+{
+ struct net_device *tdev = NULL;
+ struct ip_tunnel *tunnel = netdev_priv(dev);
+ const struct iphdr *iph;
+ int hlen = LL_MAX_HEADER;
+ int mtu = ETH_DATA_LEN;
+ int t_hlen = tunnel->hlen + sizeof(struct iphdr);
+
+ iph = &tunnel->parms.iph;
+
+ /* Guess output device to choose reasonable mtu and needed_headroom */
+ if (iph->daddr) {
+ struct flowi4 fl4;
+ struct rtable *rt;
+
+ rt = ip_route_output_tunnel(dev_net(dev), &fl4,
+ tunnel->parms.iph.protocol,
+ iph->daddr, iph->saddr,
+ tunnel->parms.o_key,
+ RT_TOS(iph->tos),
+ tunnel->parms.link);
+ if (!IS_ERR(rt)) {
+ tdev = rt->dst.dev;
+ ip_rt_put(rt);
+ }
+ if (dev->type != ARPHRD_ETHER)
+ dev->flags |= IFF_POINTOPOINT;
+ }
+
+ if (!tdev && tunnel->parms.link)
+ tdev = __dev_get_by_index(dev_net(dev), tunnel->parms.link);
+
+ if (tdev) {
+ hlen = tdev->hard_header_len + tdev->needed_headroom;
+ mtu = tdev->mtu;
+ }
+ dev->iflink = tunnel->parms.link;
+
+ dev->needed_headroom = t_hlen + hlen;
+ mtu -= (dev->hard_header_len + t_hlen);
+
+ if (mtu < 68)
+ mtu = 68;
+
+ return mtu;
+}
+
+static struct ip_tunnel *ip_tunnel_create(struct net *net,
+ struct ip_tunnel_net *itn,
+ struct ip_tunnel_parm *parms)
+{
+ struct ip_tunnel *nt, *fbt;
+ struct net_device *dev;
+
+ BUG_ON(!itn->fb_tunnel_dev);
+ fbt = netdev_priv(itn->fb_tunnel_dev);
+ dev = __ip_tunnel_create(net, itn->fb_tunnel_dev->rtnl_link_ops, parms);
+ if (IS_ERR(dev))
+ return NULL;
+
+ dev->mtu = ip_tunnel_bind_dev(dev);
+
+ nt = netdev_priv(dev);
+ ip_tunnel_add(itn, nt);
+ return nt;
+}
+
+int ip_tunnel_rcv(struct ip_tunnel *tunnel, struct sk_buff *skb,
+ const struct tnl_ptk_info *tpi, bool log_ecn_error)
+{
+ struct pcpu_tstats *tstats;
+ const struct iphdr *iph = ip_hdr(skb);
+ int err;
+
+ secpath_reset(skb);
+
+ skb->protocol = tpi->proto;
+
+ skb->mac_header = skb->network_header;
+ __pskb_pull(skb, tunnel->hlen);
+ skb_postpull_rcsum(skb, skb_transport_header(skb), tunnel->hlen);
+#ifdef CONFIG_NET_IPGRE_BROADCAST
+ if (ipv4_is_multicast(iph->daddr)) {
+ /* Looped back packet, drop it! */
+ if (rt_is_output_route(skb_rtable(skb)))
+ goto drop;
+ tunnel->dev->stats.multicast++;
+ skb->pkt_type = PACKET_BROADCAST;
+ }
+#endif
+
+ if ((!(tpi->flags&TUNNEL_CSUM) && (tunnel->parms.i_flags&TUNNEL_CSUM)) ||
+ ((tpi->flags&TUNNEL_CSUM) && !(tunnel->parms.i_flags&TUNNEL_CSUM))) {
+ tunnel->dev->stats.rx_crc_errors++;
+ tunnel->dev->stats.rx_errors++;
+ goto drop;
+ }
+
+ if (tunnel->parms.i_flags&TUNNEL_SEQ) {
+ if (!(tpi->flags&TUNNEL_SEQ) ||
+ (tunnel->i_seqno && (s32)(ntohl(tpi->seq) - tunnel->i_seqno) < 0)) {
+ tunnel->dev->stats.rx_fifo_errors++;
+ tunnel->dev->stats.rx_errors++;
+ goto drop;
+ }
+ tunnel->i_seqno = ntohl(tpi->seq) + 1;
+ }
+
+ /* Warning: All skb pointers will be invalidated! */
+ if (tunnel->dev->type == ARPHRD_ETHER) {
+ if (!pskb_may_pull(skb, ETH_HLEN)) {
+ tunnel->dev->stats.rx_length_errors++;
+ tunnel->dev->stats.rx_errors++;
+ goto drop;
+ }
+
+ iph = ip_hdr(skb);
+ skb->protocol = eth_type_trans(skb, tunnel->dev);
+ skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN);
+ }
+
+ skb->pkt_type = PACKET_HOST;
+ __skb_tunnel_rx(skb, tunnel->dev);
+
+ skb_reset_network_header(skb);
+ err = IP_ECN_decapsulate(iph, skb);
+ if (unlikely(err)) {
+ if (log_ecn_error)
+ net_info_ratelimited("non-ECT from %pI4 with TOS=%#x\n",
+ &iph->saddr, iph->tos);
+ if (err > 1) {
+ ++tunnel->dev->stats.rx_frame_errors;
+ ++tunnel->dev->stats.rx_errors;
+ goto drop;
+ }
+ }
+
+ tstats = this_cpu_ptr(tunnel->dev->tstats);
+ u64_stats_update_begin(&tstats->syncp);
+ tstats->rx_packets++;
+ tstats->rx_bytes += skb->len;
+ u64_stats_update_end(&tstats->syncp);
+
+ gro_cells_receive(&tunnel->gro_cells, skb);
+ return 0;
+
+drop:
+ kfree_skb(skb);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(ip_tunnel_rcv);
+
+void ip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev,
+ const struct iphdr *tnl_params)
+{
+ struct ip_tunnel *tunnel = netdev_priv(dev);
+ const struct iphdr *inner_iph;
+ struct iphdr *iph;
+ struct flowi4 fl4;
+ u8 tos, ttl;
+ __be16 df;
+ struct rtable *rt; /* Route to the other host */
+ struct net_device *tdev; /* Device to other host */
+ unsigned int max_headroom; /* The extra header space needed */
+ __be32 dst;
+ int mtu;
+
+ inner_iph = (const struct iphdr *)skb_inner_network_header(skb);
+
+ dst = tnl_params->daddr;
+ if (dst == 0) {
+ /* NBMA tunnel */
+
+ if (skb_dst(skb) == NULL) {
+ dev->stats.tx_fifo_errors++;
+ goto tx_error;
+ }
+
+ if (skb->protocol == htons(ETH_P_IP)) {
+ rt = skb_rtable(skb);
+ dst = rt_nexthop(rt, inner_iph->daddr);
+ }
+#if IS_ENABLED(CONFIG_IPV6)
+ else if (skb->protocol == htons(ETH_P_IPV6)) {
+ const struct in6_addr *addr6;
+ struct neighbour *neigh;
+ bool do_tx_error_icmp;
+ int addr_type;
+
+ neigh = dst_neigh_lookup(skb_dst(skb),
+ &ipv6_hdr(skb)->daddr);
+ if (neigh == NULL)
+ goto tx_error;
+
+ addr6 = (const struct in6_addr *)&neigh->primary_key;
+ addr_type = ipv6_addr_type(addr6);
+
+ if (addr_type == IPV6_ADDR_ANY) {
+ addr6 = &ipv6_hdr(skb)->daddr;
+ addr_type = ipv6_addr_type(addr6);
+ }
+
+ if ((addr_type & IPV6_ADDR_COMPATv4) == 0)
+ do_tx_error_icmp = true;
+ else {
+ do_tx_error_icmp = false;
+ dst = addr6->s6_addr32[3];
+ }
+ neigh_release(neigh);
+ if (do_tx_error_icmp)
+ goto tx_error_icmp;
+ }
+#endif
+ else
+ goto tx_error;
+ }
+
+ tos = tnl_params->tos;
+ if (tos & 0x1) {
+ tos &= ~0x1;
+ if (skb->protocol == htons(ETH_P_IP))
+ tos = inner_iph->tos;
+ else if (skb->protocol == htons(ETH_P_IPV6))
+ tos = ipv6_get_dsfield((const struct ipv6hdr *)inner_iph);
+ }
+
+ rt = ip_route_output_tunnel(dev_net(dev), &fl4,
+ tunnel->parms.iph.protocol,
+ dst, tnl_params->saddr,
+ tunnel->parms.o_key,
+ RT_TOS(tos),
+ tunnel->parms.link);
+ if (IS_ERR(rt)) {
+ dev->stats.tx_carrier_errors++;
+ goto tx_error;
+ }
+ tdev = rt->dst.dev;
+
+ if (tdev == dev) {
+ ip_rt_put(rt);
+ dev->stats.collisions++;
+ goto tx_error;
+ }
+
+ df = tnl_params->frag_off;
+
+ if (df)
+ mtu = dst_mtu(&rt->dst) - dev->hard_header_len
+ - sizeof(struct iphdr);
+ else
+ mtu = skb_dst(skb) ? dst_mtu(skb_dst(skb)) : dev->mtu;
+
+ if (skb_dst(skb))
+ skb_dst(skb)->ops->update_pmtu(skb_dst(skb), NULL, skb, mtu);
+
+ if (skb->protocol == htons(ETH_P_IP)) {
+ df |= (inner_iph->frag_off&htons(IP_DF));
+
+ if (!skb_is_gso(skb) &&
+ (inner_iph->frag_off&htons(IP_DF)) &&
+ mtu < ntohs(inner_iph->tot_len)) {
+ icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, htonl(mtu));
+ ip_rt_put(rt);
+ goto tx_error;
+ }
+ }
+#if IS_ENABLED(CONFIG_IPV6)
+ else if (skb->protocol == htons(ETH_P_IPV6)) {
+ struct rt6_info *rt6 = (struct rt6_info *)skb_dst(skb);
+
+ if (rt6 && mtu < dst_mtu(skb_dst(skb)) &&
+ mtu >= IPV6_MIN_MTU) {
+ if ((tunnel->parms.iph.daddr &&
+ !ipv4_is_multicast(tunnel->parms.iph.daddr)) ||
+ rt6->rt6i_dst.plen == 128) {
+ rt6->rt6i_flags |= RTF_MODIFIED;
+ dst_metric_set(skb_dst(skb), RTAX_MTU, mtu);
+ }
+ }
+
+ if (!skb_is_gso(skb) && mtu >= IPV6_MIN_MTU &&
+ mtu < skb->len) {
+ icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
+ ip_rt_put(rt);
+ goto tx_error;
+ }
+ }
+#endif
+
+ if (tunnel->err_count > 0) {
+ if (time_before(jiffies,
+ tunnel->err_time + IPTUNNEL_ERR_TIMEO)) {
+ tunnel->err_count--;
+
+ dst_link_failure(skb);
+ } else
+ tunnel->err_count = 0;
+ }
+
+ ttl = tnl_params->ttl;
+ if (ttl == 0) {
+ if (skb->protocol == htons(ETH_P_IP))
+ ttl = inner_iph->ttl;
+#if IS_ENABLED(CONFIG_IPV6)
+ else if (skb->protocol == htons(ETH_P_IPV6))
+ ttl = ((const struct ipv6hdr *)inner_iph)->hop_limit;
+#endif
+ else
+ ttl = ip4_dst_hoplimit(&rt->dst);
+ }
+
+ max_headroom = LL_RESERVED_SPACE(tdev) + sizeof(struct iphdr)
+ + rt->dst.header_len;
+ if (max_headroom > dev->needed_headroom) {
+ dev->needed_headroom = max_headroom;
+ if (skb_cow_head(skb, dev->needed_headroom)) {
+ dev->stats.tx_dropped++;
+ dev_kfree_skb(skb);
+ return;
+ }
+ }
+
+ skb_dst_drop(skb);
+ skb_dst_set(skb, &rt->dst);
+ memset(IPCB(skb), 0, sizeof(*IPCB(skb)));
+
+ /* Push down and install the IP header. */
+ skb_push(skb, sizeof(struct iphdr));
+ skb_reset_network_header(skb);
+
+ iph = ip_hdr(skb);
+ inner_iph = (const struct iphdr *)skb_inner_network_header(skb);
+
+ iph->version = 4;
+ iph->ihl = sizeof(struct iphdr) >> 2;
+ iph->frag_off = df;
+ iph->protocol = tnl_params->protocol;
+ iph->tos = ip_tunnel_ecn_encap(tos, inner_iph, skb);
+ iph->daddr = fl4.daddr;
+ iph->saddr = fl4.saddr;
+ iph->ttl = ttl;
+ tunnel_ip_select_ident(skb, inner_iph, &rt->dst);
+
+ iptunnel_xmit(skb, dev);
+ return;
+
+#if IS_ENABLED(CONFIG_IPV6)
+tx_error_icmp:
+ dst_link_failure(skb);
+#endif
+tx_error:
+ dev->stats.tx_errors++;
+ dev_kfree_skb(skb);
+}
+EXPORT_SYMBOL_GPL(ip_tunnel_xmit);
+
+static void ip_tunnel_update(struct ip_tunnel_net *itn,
+ struct ip_tunnel *t,
+ struct net_device *dev,
+ struct ip_tunnel_parm *p,
+ bool set_mtu)
+{
+ ip_tunnel_del(t);
+ t->parms.iph.saddr = p->iph.saddr;
+ t->parms.iph.daddr = p->iph.daddr;
+ t->parms.i_key = p->i_key;
+ t->parms.o_key = p->o_key;
+ if (dev->type != ARPHRD_ETHER) {
+ memcpy(dev->dev_addr, &p->iph.saddr, 4);
+ memcpy(dev->broadcast, &p->iph.daddr, 4);
+ }
+ ip_tunnel_add(itn, t);
+
+ t->parms.iph.ttl = p->iph.ttl;
+ t->parms.iph.tos = p->iph.tos;
+ t->parms.iph.frag_off = p->iph.frag_off;
+
+ if (t->parms.link != p->link) {
+ int mtu;
+
+ t->parms.link = p->link;
+ mtu = ip_tunnel_bind_dev(dev);
+ if (set_mtu)
+ dev->mtu = mtu;
+ }
+ netdev_state_change(dev);
+}
+
+int ip_tunnel_ioctl(struct net_device *dev, struct ip_tunnel_parm *p, int cmd)
+{
+ int err = 0;
+ struct ip_tunnel *t;
+ struct net *net = dev_net(dev);
+ struct ip_tunnel *tunnel = netdev_priv(dev);
+ struct ip_tunnel_net *itn = net_generic(net, tunnel->ip_tnl_net_id);
+
+ BUG_ON(!itn->fb_tunnel_dev);
+ switch (cmd) {
+ case SIOCGETTUNNEL:
+ t = NULL;
+ if (dev == itn->fb_tunnel_dev)
+ t = ip_tunnel_find(itn, p, itn->fb_tunnel_dev->type);
+ if (t == NULL)
+ t = netdev_priv(dev);
+ memcpy(p, &t->parms, sizeof(*p));
+ break;
+
+ case SIOCADDTUNNEL:
+ case SIOCCHGTUNNEL:
+ err = -EPERM;
+ if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
+ goto done;
+ if (p->iph.ttl)
+ p->iph.frag_off |= htons(IP_DF);
+ if (!(p->i_flags&TUNNEL_KEY))
+ p->i_key = 0;
+ if (!(p->o_flags&TUNNEL_KEY))
+ p->o_key = 0;
+
+ t = ip_tunnel_find(itn, p, itn->fb_tunnel_dev->type);
+
+ if (!t && (cmd == SIOCADDTUNNEL))
+ t = ip_tunnel_create(net, itn, p);
+
+ if (dev != itn->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
+ if (t != NULL) {
+ if (t->dev != dev) {
+ err = -EEXIST;
+ break;
+ }
+ } else {
+ unsigned int nflags = 0;
+
+ if (ipv4_is_multicast(p->iph.daddr))
+ nflags = IFF_BROADCAST;
+ else if (p->iph.daddr)
+ nflags = IFF_POINTOPOINT;
+
+ if ((dev->flags^nflags)&(IFF_POINTOPOINT|IFF_BROADCAST)) {
+ err = -EINVAL;
+ break;
+ }
+
+ t = netdev_priv(dev);
+ }
+ }
+
+ if (t) {
+ err = 0;
+ ip_tunnel_update(itn, t, dev, p, true);
+ } else
+ err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
+ break;
+
+ case SIOCDELTUNNEL:
+ err = -EPERM;
+ if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
+ goto done;
+
+ if (dev == itn->fb_tunnel_dev) {
+ err = -ENOENT;
+ t = ip_tunnel_find(itn, p, itn->fb_tunnel_dev->type);
+ if (t == NULL)
+ goto done;
+ err = -EPERM;
+ if (t == netdev_priv(itn->fb_tunnel_dev))
+ goto done;
+ dev = t->dev;
+ }
+ unregister_netdevice(dev);
+ err = 0;
+ break;
+
+ default:
+ err = -EINVAL;
+ }
+
+done:
+ return err;
+}
+EXPORT_SYMBOL_GPL(ip_tunnel_ioctl);
+
+int ip_tunnel_change_mtu(struct net_device *dev, int new_mtu)
+{
+ struct ip_tunnel *tunnel = netdev_priv(dev);
+ int t_hlen = tunnel->hlen + sizeof(struct iphdr);
+
+ if (new_mtu < 68 ||
+ new_mtu > 0xFFF8 - dev->hard_header_len - t_hlen)
+ return -EINVAL;
+ dev->mtu = new_mtu;
+ return 0;
+}
+EXPORT_SYMBOL_GPL(ip_tunnel_change_mtu);
+
+static void ip_tunnel_dev_free(struct net_device *dev)
+{
+ struct ip_tunnel *tunnel = netdev_priv(dev);
+
+ gro_cells_destroy(&tunnel->gro_cells);
+ free_percpu(dev->tstats);
+ free_netdev(dev);
+}
+
+void ip_tunnel_dellink(struct net_device *dev, struct list_head *head)
+{
+ struct net *net = dev_net(dev);
+ struct ip_tunnel *tunnel = netdev_priv(dev);
+ struct ip_tunnel_net *itn;
+
+ itn = net_generic(net, tunnel->ip_tnl_net_id);
+
+ if (itn->fb_tunnel_dev != dev) {
+ ip_tunnel_del(netdev_priv(dev));
+ unregister_netdevice_queue(dev, head);
+ }
+}
+EXPORT_SYMBOL_GPL(ip_tunnel_dellink);
+
+int __net_init ip_tunnel_init_net(struct net *net, int ip_tnl_net_id,
+ struct rtnl_link_ops *ops, char *devname)
+{
+ struct ip_tunnel_net *itn = net_generic(net, ip_tnl_net_id);
+ struct ip_tunnel_parm parms;
+
+ itn->tunnels = kzalloc(IP_TNL_HASH_SIZE * sizeof(struct hlist_head), GFP_KERNEL);
+ if (!itn->tunnels)
+ return -ENOMEM;
+
+ if (!ops) {
+ itn->fb_tunnel_dev = NULL;
+ return 0;
+ }
+ memset(&parms, 0, sizeof(parms));
+ if (devname)
+ strlcpy(parms.name, devname, IFNAMSIZ);
+
+ rtnl_lock();
+ itn->fb_tunnel_dev = __ip_tunnel_create(net, ops, &parms);
+ rtnl_unlock();
+ if (IS_ERR(itn->fb_tunnel_dev)) {
+ kfree(itn->tunnels);
+ return PTR_ERR(itn->fb_tunnel_dev);
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(ip_tunnel_init_net);
+
+static void ip_tunnel_destroy(struct ip_tunnel_net *itn, struct list_head *head)
+{
+ int h;
+
+ for (h = 0; h < IP_TNL_HASH_SIZE; h++) {
+ struct ip_tunnel *t;
+ struct hlist_node *n;
+ struct hlist_head *thead = &itn->tunnels[h];
+
+ hlist_for_each_entry_safe(t, n, thead, hash_node)
+ unregister_netdevice_queue(t->dev, head);
+ }
+ if (itn->fb_tunnel_dev)
+ unregister_netdevice_queue(itn->fb_tunnel_dev, head);
+}
+
+void __net_exit ip_tunnel_delete_net(struct ip_tunnel_net *itn)
+{
+ LIST_HEAD(list);
+
+ rtnl_lock();
+ ip_tunnel_destroy(itn, &list);
+ unregister_netdevice_many(&list);
+ rtnl_unlock();
+ kfree(itn->tunnels);
+}
+EXPORT_SYMBOL_GPL(ip_tunnel_delete_net);
+
+int ip_tunnel_newlink(struct net_device *dev, struct nlattr *tb[],
+ struct ip_tunnel_parm *p)
+{
+ struct ip_tunnel *nt;
+ struct net *net = dev_net(dev);
+ struct ip_tunnel_net *itn;
+ int mtu;
+ int err;
+
+ nt = netdev_priv(dev);
+ itn = net_generic(net, nt->ip_tnl_net_id);
+
+ if (ip_tunnel_find(itn, p, dev->type))
+ return -EEXIST;
+
+ nt->parms = *p;
+ err = register_netdevice(dev);
+ if (err)
+ goto out;
+
+ if (dev->type == ARPHRD_ETHER && !tb[IFLA_ADDRESS])
+ eth_hw_addr_random(dev);
+
+ mtu = ip_tunnel_bind_dev(dev);
+ if (!tb[IFLA_MTU])
+ dev->mtu = mtu;
+
+ ip_tunnel_add(itn, nt);
+
+out:
+ return err;
+}
+EXPORT_SYMBOL_GPL(ip_tunnel_newlink);
+
+int ip_tunnel_changelink(struct net_device *dev, struct nlattr *tb[],
+ struct ip_tunnel_parm *p)
+{
+ struct ip_tunnel *t, *nt;
+ struct net *net = dev_net(dev);
+ struct ip_tunnel *tunnel = netdev_priv(dev);
+ struct ip_tunnel_net *itn = net_generic(net, tunnel->ip_tnl_net_id);
+
+ if (dev == itn->fb_tunnel_dev)
+ return -EINVAL;
+
+ nt = netdev_priv(dev);
+
+ t = ip_tunnel_find(itn, p, dev->type);
+
+ if (t) {
+ if (t->dev != dev)
+ return -EEXIST;
+ } else {
+ t = nt;
+
+ if (dev->type != ARPHRD_ETHER) {
+ unsigned int nflags = 0;
+
+ if (ipv4_is_multicast(p->iph.daddr))
+ nflags = IFF_BROADCAST;
+ else if (p->iph.daddr)
+ nflags = IFF_POINTOPOINT;
+
+ if ((dev->flags ^ nflags) &
+ (IFF_POINTOPOINT | IFF_BROADCAST))
+ return -EINVAL;
+ }
+ }
+
+ ip_tunnel_update(itn, t, dev, p, !tb[IFLA_MTU]);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(ip_tunnel_changelink);
+
+int ip_tunnel_init(struct net_device *dev)
+{
+ struct ip_tunnel *tunnel = netdev_priv(dev);
+ struct iphdr *iph = &tunnel->parms.iph;
+ int err;
+
+ dev->destructor = ip_tunnel_dev_free;
+ dev->tstats = alloc_percpu(struct pcpu_tstats);
+ if (!dev->tstats)
+ return -ENOMEM;
+
+ err = gro_cells_init(&tunnel->gro_cells, dev);
+ if (err) {
+ free_percpu(dev->tstats);
+ return err;
+ }
+
+ tunnel->dev = dev;
+ strcpy(tunnel->parms.name, dev->name);
+ iph->version = 4;
+ iph->ihl = 5;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(ip_tunnel_init);
+
+void ip_tunnel_uninit(struct net_device *dev)
+{
+ struct net *net = dev_net(dev);
+ struct ip_tunnel *tunnel = netdev_priv(dev);
+ struct ip_tunnel_net *itn;
+
+ itn = net_generic(net, tunnel->ip_tnl_net_id);
+ /* fb_tunnel_dev will be unregisted in net-exit call. */
+ if (itn->fb_tunnel_dev != dev)
+ ip_tunnel_del(netdev_priv(dev));
+}
+EXPORT_SYMBOL_GPL(ip_tunnel_uninit);
+
+/* Do least required initialization, rest of init is done in tunnel_init call */
+void ip_tunnel_setup(struct net_device *dev, int net_id)
+{
+ struct ip_tunnel *tunnel = netdev_priv(dev);
+ tunnel->ip_tnl_net_id = net_id;
+}
+EXPORT_SYMBOL_GPL(ip_tunnel_setup);
+
+MODULE_LICENSE("GPL");
