gre: Support GRE over IPv6
GRE over IPv6 implementation.
Signed-off-by: Dmitry Kozlov <xeb@mail.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/ip6_gre.c b/net/ipv6/ip6_gre.c
new file mode 100644
index 0000000..a84ad5d
--- /dev/null
+++ b/net/ipv6/ip6_gre.c
@@ -0,0 +1,1790 @@
+/*
+ * GRE over IPv6 protocol decoder.
+ *
+ * Authors: Dmitry Kozlov (xeb@mail.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 <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/hash.h>
+#include <linux/if_tunnel.h>
+#include <linux/ip6_tunnel.h>
+
+#include <net/sock.h>
+#include <net/ip.h>
+#include <net/icmp.h>
+#include <net/protocol.h>
+#include <net/addrconf.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/ipv6.h>
+#include <net/ip6_fib.h>
+#include <net/ip6_route.h>
+#include <net/ip6_tunnel.h>
+
+
+#define IPV6_TCLASS_MASK (IPV6_FLOWINFO_MASK & ~IPV6_FLOWLABEL_MASK)
+#define IPV6_TCLASS_SHIFT 20
+
+#define HASH_SIZE_SHIFT 5
+#define HASH_SIZE (1 << HASH_SIZE_SHIFT)
+
+static int ip6gre_net_id __read_mostly;
+struct ip6gre_net {
+ struct ip6_tnl __rcu *tunnels[4][HASH_SIZE];
+
+ struct net_device *fb_tunnel_dev;
+};
+
+static struct rtnl_link_ops ip6gre_link_ops __read_mostly;
+static int ip6gre_tunnel_init(struct net_device *dev);
+static void ip6gre_tunnel_setup(struct net_device *dev);
+static void ip6gre_tunnel_link(struct ip6gre_net *ign, struct ip6_tnl *t);
+static void ip6gre_tnl_link_config(struct ip6_tnl *t, int set_mtu);
+
+/* Tunnel hash table */
+
+/*
+ 4 hash tables:
+
+ 3: (remote,local)
+ 2: (remote,*)
+ 1: (*,local)
+ 0: (*,*)
+
+ 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.
+ */
+
+#define HASH_KEY(key) (((__force u32)key^((__force u32)key>>4))&(HASH_SIZE - 1))
+static u32 HASH_ADDR(const struct in6_addr *addr)
+{
+ u32 hash = ipv6_addr_hash(addr);
+
+ return hash_32(hash, HASH_SIZE_SHIFT);
+}
+
+#define tunnels_r_l tunnels[3]
+#define tunnels_r tunnels[2]
+#define tunnels_l tunnels[1]
+#define tunnels_wc tunnels[0]
+/*
+ * Locking : hash tables are protected by RCU and RTNL
+ */
+
+#define for_each_ip_tunnel_rcu(start) \
+ for (t = rcu_dereference(start); t; t = rcu_dereference(t->next))
+
+/* often modified stats are per cpu, other are shared (netdev->stats) */
+struct pcpu_tstats {
+ u64 rx_packets;
+ u64 rx_bytes;
+ u64 tx_packets;
+ u64 tx_bytes;
+ struct u64_stats_sync syncp;
+};
+
+static struct rtnl_link_stats64 *ip6gre_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_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;
+
+ return tot;
+}
+
+/* Given src, dst and key, find appropriate for input tunnel. */
+
+static struct ip6_tnl *ip6gre_tunnel_lookup(struct net_device *dev,
+ const struct in6_addr *remote, const struct in6_addr *local,
+ __be32 key, __be16 gre_proto)
+{
+ struct net *net = dev_net(dev);
+ int link = dev->ifindex;
+ unsigned int h0 = HASH_ADDR(remote);
+ unsigned int h1 = HASH_KEY(key);
+ struct ip6_tnl *t, *cand = NULL;
+ struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
+ int dev_type = (gre_proto == htons(ETH_P_TEB)) ?
+ ARPHRD_ETHER : ARPHRD_IP6GRE;
+ int score, cand_score = 4;
+
+ for_each_ip_tunnel_rcu(ign->tunnels_r_l[h0 ^ h1]) {
+ if (!ipv6_addr_equal(local, &t->parms.laddr) ||
+ !ipv6_addr_equal(remote, &t->parms.raddr) ||
+ key != t->parms.i_key ||
+ !(t->dev->flags & IFF_UP))
+ continue;
+
+ if (t->dev->type != ARPHRD_IP6GRE &&
+ t->dev->type != dev_type)
+ continue;
+
+ score = 0;
+ if (t->parms.link != link)
+ score |= 1;
+ if (t->dev->type != dev_type)
+ score |= 2;
+ if (score == 0)
+ return t;
+
+ if (score < cand_score) {
+ cand = t;
+ cand_score = score;
+ }
+ }
+
+ for_each_ip_tunnel_rcu(ign->tunnels_r[h0 ^ h1]) {
+ if (!ipv6_addr_equal(remote, &t->parms.raddr) ||
+ key != t->parms.i_key ||
+ !(t->dev->flags & IFF_UP))
+ continue;
+
+ if (t->dev->type != ARPHRD_IP6GRE &&
+ t->dev->type != dev_type)
+ continue;
+
+ score = 0;
+ if (t->parms.link != link)
+ score |= 1;
+ if (t->dev->type != dev_type)
+ score |= 2;
+ if (score == 0)
+ return t;
+
+ if (score < cand_score) {
+ cand = t;
+ cand_score = score;
+ }
+ }
+
+ for_each_ip_tunnel_rcu(ign->tunnels_l[h1]) {
+ if ((!ipv6_addr_equal(local, &t->parms.laddr) &&
+ (!ipv6_addr_equal(local, &t->parms.raddr) ||
+ !ipv6_addr_is_multicast(local))) ||
+ key != t->parms.i_key ||
+ !(t->dev->flags & IFF_UP))
+ continue;
+
+ if (t->dev->type != ARPHRD_IP6GRE &&
+ t->dev->type != dev_type)
+ continue;
+
+ score = 0;
+ if (t->parms.link != link)
+ score |= 1;
+ if (t->dev->type != dev_type)
+ score |= 2;
+ if (score == 0)
+ return t;
+
+ if (score < cand_score) {
+ cand = t;
+ cand_score = score;
+ }
+ }
+
+ for_each_ip_tunnel_rcu(ign->tunnels_wc[h1]) {
+ if (t->parms.i_key != key ||
+ !(t->dev->flags & IFF_UP))
+ continue;
+
+ if (t->dev->type != ARPHRD_IP6GRE &&
+ t->dev->type != dev_type)
+ continue;
+
+ score = 0;
+ if (t->parms.link != link)
+ score |= 1;
+ if (t->dev->type != dev_type)
+ score |= 2;
+ if (score == 0)
+ return t;
+
+ if (score < cand_score) {
+ cand = t;
+ cand_score = score;
+ }
+ }
+
+ if (cand != NULL)
+ return cand;
+
+ dev = ign->fb_tunnel_dev;
+ if (dev->flags & IFF_UP)
+ return netdev_priv(dev);
+
+ return NULL;
+}
+
+static struct ip6_tnl __rcu **__ip6gre_bucket(struct ip6gre_net *ign,
+ const struct __ip6_tnl_parm *p)
+{
+ const struct in6_addr *remote = &p->raddr;
+ const struct in6_addr *local = &p->laddr;
+ unsigned int h = HASH_KEY(p->i_key);
+ int prio = 0;
+
+ if (!ipv6_addr_any(local))
+ prio |= 1;
+ if (!ipv6_addr_any(remote) && !ipv6_addr_is_multicast(remote)) {
+ prio |= 2;
+ h ^= HASH_ADDR(remote);
+ }
+
+ return &ign->tunnels[prio][h];
+}
+
+static inline struct ip6_tnl __rcu **ip6gre_bucket(struct ip6gre_net *ign,
+ const struct ip6_tnl *t)
+{
+ return __ip6gre_bucket(ign, &t->parms);
+}
+
+static void ip6gre_tunnel_link(struct ip6gre_net *ign, struct ip6_tnl *t)
+{
+ struct ip6_tnl __rcu **tp = ip6gre_bucket(ign, t);
+
+ rcu_assign_pointer(t->next, rtnl_dereference(*tp));
+ rcu_assign_pointer(*tp, t);
+}
+
+static void ip6gre_tunnel_unlink(struct ip6gre_net *ign, struct ip6_tnl *t)
+{
+ struct ip6_tnl __rcu **tp;
+ struct ip6_tnl *iter;
+
+ for (tp = ip6gre_bucket(ign, t);
+ (iter = rtnl_dereference(*tp)) != NULL;
+ tp = &iter->next) {
+ if (t == iter) {
+ rcu_assign_pointer(*tp, t->next);
+ break;
+ }
+ }
+}
+
+static struct ip6_tnl *ip6gre_tunnel_find(struct net *net,
+ const struct __ip6_tnl_parm *parms,
+ int type)
+{
+ const struct in6_addr *remote = &parms->raddr;
+ const struct in6_addr *local = &parms->laddr;
+ __be32 key = parms->i_key;
+ int link = parms->link;
+ struct ip6_tnl *t;
+ struct ip6_tnl __rcu **tp;
+ struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
+
+ for (tp = __ip6gre_bucket(ign, parms);
+ (t = rtnl_dereference(*tp)) != NULL;
+ tp = &t->next)
+ if (ipv6_addr_equal(local, &t->parms.laddr) &&
+ ipv6_addr_equal(remote, &t->parms.raddr) &&
+ key == t->parms.i_key &&
+ link == t->parms.link &&
+ type == t->dev->type)
+ break;
+
+ return t;
+}
+
+static struct ip6_tnl *ip6gre_tunnel_locate(struct net *net,
+ const struct __ip6_tnl_parm *parms, int create)
+{
+ struct ip6_tnl *t, *nt;
+ struct net_device *dev;
+ char name[IFNAMSIZ];
+ struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
+
+ t = ip6gre_tunnel_find(net, parms, ARPHRD_IP6GRE);
+ if (t || !create)
+ return t;
+
+ if (parms->name[0])
+ strlcpy(name, parms->name, IFNAMSIZ);
+ else
+ strcpy(name, "ip6gre%d");
+
+ dev = alloc_netdev(sizeof(*t), name, ip6gre_tunnel_setup);
+ if (!dev)
+ return NULL;
+
+ dev_net_set(dev, net);
+
+ nt = netdev_priv(dev);
+ nt->parms = *parms;
+ dev->rtnl_link_ops = &ip6gre_link_ops;
+
+ nt->dev = dev;
+ ip6gre_tnl_link_config(nt, 1);
+
+ if (register_netdevice(dev) < 0)
+ goto failed_free;
+
+ /* Can use a lockless transmit, unless we generate output sequences */
+ if (!(nt->parms.o_flags & GRE_SEQ))
+ dev->features |= NETIF_F_LLTX;
+
+ dev_hold(dev);
+ ip6gre_tunnel_link(ign, nt);
+ return nt;
+
+failed_free:
+ free_netdev(dev);
+ return NULL;
+}
+
+static void ip6gre_tunnel_uninit(struct net_device *dev)
+{
+ struct net *net = dev_net(dev);
+ struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
+
+ ip6gre_tunnel_unlink(ign, netdev_priv(dev));
+ dev_put(dev);
+}
+
+
+static void ip6gre_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
+ u8 type, u8 code, int offset, __be32 info)
+{
+ const struct ipv6hdr *ipv6h = (const struct ipv6hdr *)skb->data;
+ __be16 *p = (__be16 *)(ipv6h + 1);
+ int grehlen = sizeof(ipv6h) + 4;
+ struct ip6_tnl *t;
+ __be16 flags;
+
+ flags = p[0];
+ if (flags&(GRE_CSUM|GRE_KEY|GRE_SEQ|GRE_ROUTING|GRE_VERSION)) {
+ if (flags&(GRE_VERSION|GRE_ROUTING))
+ return;
+ if (flags&GRE_KEY) {
+ grehlen += 4;
+ if (flags&GRE_CSUM)
+ grehlen += 4;
+ }
+ }
+
+ /* If only 8 bytes returned, keyed message will be dropped here */
+ if (skb_headlen(skb) < grehlen)
+ return;
+
+ rcu_read_lock();
+
+ t = ip6gre_tunnel_lookup(skb->dev, &ipv6h->daddr, &ipv6h->saddr,
+ flags & GRE_KEY ?
+ *(((__be32 *)p) + (grehlen / 4) - 1) : 0,
+ p[1]);
+ if (t == NULL)
+ goto out;
+
+ switch (type) {
+ __u32 teli;
+ struct ipv6_tlv_tnl_enc_lim *tel;
+ __u32 mtu;
+ case ICMPV6_DEST_UNREACH:
+ net_warn_ratelimited("%s: Path to destination invalid or inactive!\n",
+ t->parms.name);
+ break;
+ case ICMPV6_TIME_EXCEED:
+ if (code == ICMPV6_EXC_HOPLIMIT) {
+ net_warn_ratelimited("%s: Too small hop limit or routing loop in tunnel!\n",
+ t->parms.name);
+ }
+ break;
+ case ICMPV6_PARAMPROB:
+ teli = 0;
+ if (code == ICMPV6_HDR_FIELD)
+ teli = ip6_tnl_parse_tlv_enc_lim(skb, skb->data);
+
+ if (teli && teli == info - 2) {
+ tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->data[teli];
+ if (tel->encap_limit == 0) {
+ net_warn_ratelimited("%s: Too small encapsulation limit or routing loop in tunnel!\n",
+ t->parms.name);
+ }
+ } else {
+ net_warn_ratelimited("%s: Recipient unable to parse tunneled packet!\n",
+ t->parms.name);
+ }
+ break;
+ case ICMPV6_PKT_TOOBIG:
+ mtu = info - offset;
+ if (mtu < IPV6_MIN_MTU)
+ mtu = IPV6_MIN_MTU;
+ t->dev->mtu = mtu;
+ break;
+ }
+
+ if (time_before(jiffies, t->err_time + IP6TUNNEL_ERR_TIMEO))
+ t->err_count++;
+ else
+ t->err_count = 1;
+ t->err_time = jiffies;
+out:
+ rcu_read_unlock();
+}
+
+static inline void ip6gre_ecn_decapsulate_ipv4(const struct ip6_tnl *t,
+ const struct ipv6hdr *ipv6h, struct sk_buff *skb)
+{
+ __u8 dsfield = ipv6_get_dsfield(ipv6h) & ~INET_ECN_MASK;
+
+ if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY)
+ ipv4_change_dsfield(ip_hdr(skb), INET_ECN_MASK, dsfield);
+
+ if (INET_ECN_is_ce(dsfield))
+ IP_ECN_set_ce(ip_hdr(skb));
+}
+
+static inline void ip6gre_ecn_decapsulate_ipv6(const struct ip6_tnl *t,
+ const struct ipv6hdr *ipv6h, struct sk_buff *skb)
+{
+ if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY)
+ ipv6_copy_dscp(ipv6_get_dsfield(ipv6h), ipv6_hdr(skb));
+
+ if (INET_ECN_is_ce(ipv6_get_dsfield(ipv6h)))
+ IP6_ECN_set_ce(ipv6_hdr(skb));
+}
+
+static int ip6gre_rcv(struct sk_buff *skb)
+{
+ const struct ipv6hdr *ipv6h;
+ u8 *h;
+ __be16 flags;
+ __sum16 csum = 0;
+ __be32 key = 0;
+ u32 seqno = 0;
+ struct ip6_tnl *tunnel;
+ int offset = 4;
+ __be16 gre_proto;
+
+ if (!pskb_may_pull(skb, sizeof(struct in6_addr)))
+ goto drop_nolock;
+
+ ipv6h = ipv6_hdr(skb);
+ h = skb->data;
+ flags = *(__be16 *)h;
+
+ if (flags&(GRE_CSUM|GRE_KEY|GRE_ROUTING|GRE_SEQ|GRE_VERSION)) {
+ /* - Version must be 0.
+ - We do not support routing headers.
+ */
+ if (flags&(GRE_VERSION|GRE_ROUTING))
+ goto drop_nolock;
+
+ if (flags&GRE_CSUM) {
+ switch (skb->ip_summed) {
+ case CHECKSUM_COMPLETE:
+ csum = csum_fold(skb->csum);
+ if (!csum)
+ break;
+ /* fall through */
+ case CHECKSUM_NONE:
+ skb->csum = 0;
+ csum = __skb_checksum_complete(skb);
+ skb->ip_summed = CHECKSUM_COMPLETE;
+ }
+ offset += 4;
+ }
+ if (flags&GRE_KEY) {
+ key = *(__be32 *)(h + offset);
+ offset += 4;
+ }
+ if (flags&GRE_SEQ) {
+ seqno = ntohl(*(__be32 *)(h + offset));
+ offset += 4;
+ }
+ }
+
+ gre_proto = *(__be16 *)(h + 2);
+
+ rcu_read_lock();
+ tunnel = ip6gre_tunnel_lookup(skb->dev,
+ &ipv6h->saddr, &ipv6h->daddr, key,
+ gre_proto);
+ if (tunnel) {
+ struct pcpu_tstats *tstats;
+
+ if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
+ goto drop;
+
+ if (!ip6_tnl_rcv_ctl(tunnel, &ipv6h->daddr, &ipv6h->saddr)) {
+ tunnel->dev->stats.rx_dropped++;
+ goto drop;
+ }
+
+ secpath_reset(skb);
+
+ skb->protocol = gre_proto;
+ /* WCCP version 1 and 2 protocol decoding.
+ * - Change protocol to IP
+ * - When dealing with WCCPv2, Skip extra 4 bytes in GRE header
+ */
+ if (flags == 0 && gre_proto == htons(ETH_P_WCCP)) {
+ skb->protocol = htons(ETH_P_IP);
+ if ((*(h + offset) & 0xF0) != 0x40)
+ offset += 4;
+ }
+
+ skb->mac_header = skb->network_header;
+ __pskb_pull(skb, offset);
+ skb_postpull_rcsum(skb, skb_transport_header(skb), offset);
+ skb->pkt_type = PACKET_HOST;
+
+ if (((flags&GRE_CSUM) && csum) ||
+ (!(flags&GRE_CSUM) && tunnel->parms.i_flags&GRE_CSUM)) {
+ tunnel->dev->stats.rx_crc_errors++;
+ tunnel->dev->stats.rx_errors++;
+ goto drop;
+ }
+ if (tunnel->parms.i_flags&GRE_SEQ) {
+ if (!(flags&GRE_SEQ) ||
+ (tunnel->i_seqno &&
+ (s32)(seqno - tunnel->i_seqno) < 0)) {
+ tunnel->dev->stats.rx_fifo_errors++;
+ tunnel->dev->stats.rx_errors++;
+ goto drop;
+ }
+ tunnel->i_seqno = seqno + 1;
+ }
+
+ /* Warning: All skb pointers will be invalidated! */
+ if (tunnel->dev->type == ARPHRD_ETHER) {
+ if (!pskb_may_pull(skb, ETH_HLEN)) {
+ tunnel->dev->stats.rx_length_errors++;
+ tunnel->dev->stats.rx_errors++;
+ goto drop;
+ }
+
+ ipv6h = ipv6_hdr(skb);
+ skb->protocol = eth_type_trans(skb, tunnel->dev);
+ skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN);
+ }
+
+ tstats = this_cpu_ptr(tunnel->dev->tstats);
+ u64_stats_update_begin(&tstats->syncp);
+ tstats->rx_packets++;
+ tstats->rx_bytes += skb->len;
+ u64_stats_update_end(&tstats->syncp);
+
+ __skb_tunnel_rx(skb, tunnel->dev);
+
+ skb_reset_network_header(skb);
+ if (skb->protocol == htons(ETH_P_IP))
+ ip6gre_ecn_decapsulate_ipv4(tunnel, ipv6h, skb);
+ else if (skb->protocol == htons(ETH_P_IPV6))
+ ip6gre_ecn_decapsulate_ipv6(tunnel, ipv6h, skb);
+
+ netif_rx(skb);
+
+ rcu_read_unlock();
+ return 0;
+ }
+ icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
+
+drop:
+ rcu_read_unlock();
+drop_nolock:
+ kfree_skb(skb);
+ return 0;
+}
+
+struct ipv6_tel_txoption {
+ struct ipv6_txoptions ops;
+ __u8 dst_opt[8];
+};
+
+static void init_tel_txopt(struct ipv6_tel_txoption *opt, __u8 encap_limit)
+{
+ memset(opt, 0, sizeof(struct ipv6_tel_txoption));
+
+ opt->dst_opt[2] = IPV6_TLV_TNL_ENCAP_LIMIT;
+ opt->dst_opt[3] = 1;
+ opt->dst_opt[4] = encap_limit;
+ opt->dst_opt[5] = IPV6_TLV_PADN;
+ opt->dst_opt[6] = 1;
+
+ opt->ops.dst0opt = (struct ipv6_opt_hdr *) opt->dst_opt;
+ opt->ops.opt_nflen = 8;
+}
+
+static netdev_tx_t ip6gre_xmit2(struct sk_buff *skb,
+ struct net_device *dev,
+ __u8 dsfield,
+ struct flowi6 *fl6,
+ int encap_limit,
+ __u32 *pmtu)
+{
+ struct net *net = dev_net(dev);
+ struct ip6_tnl *tunnel = netdev_priv(dev);
+ struct net_device *tdev; /* Device to other host */
+ struct ipv6hdr *ipv6h; /* Our new IP header */
+ unsigned int max_headroom; /* The extra header space needed */
+ int gre_hlen;
+ struct ipv6_tel_txoption opt;
+ int mtu;
+ struct dst_entry *dst = NULL, *ndst = NULL;
+ struct net_device_stats *stats = &tunnel->dev->stats;
+ int err = -1;
+ u8 proto;
+ int pkt_len;
+ struct sk_buff *new_skb;
+
+ if (dev->type == ARPHRD_ETHER)
+ IPCB(skb)->flags = 0;
+
+ if (dev->header_ops && dev->type == ARPHRD_IP6GRE) {
+ gre_hlen = 0;
+ ipv6h = (struct ipv6hdr *)skb->data;
+ fl6->daddr = ipv6h->daddr;
+ } else {
+ gre_hlen = tunnel->hlen;
+ fl6->daddr = tunnel->parms.raddr;
+ }
+
+ if (!fl6->flowi6_mark)
+ dst = ip6_tnl_dst_check(tunnel);
+
+ if (!dst) {
+ ndst = ip6_route_output(net, NULL, fl6);
+
+ if (ndst->error)
+ goto tx_err_link_failure;
+ ndst = xfrm_lookup(net, ndst, flowi6_to_flowi(fl6), NULL, 0);
+ if (IS_ERR(ndst)) {
+ err = PTR_ERR(ndst);
+ ndst = NULL;
+ goto tx_err_link_failure;
+ }
+ dst = ndst;
+ }
+
+ tdev = dst->dev;
+
+ if (tdev == dev) {
+ stats->collisions++;
+ net_warn_ratelimited("%s: Local routing loop detected!\n",
+ tunnel->parms.name);
+ goto tx_err_dst_release;
+ }
+
+ mtu = dst_mtu(dst) - sizeof(*ipv6h);
+ if (encap_limit >= 0) {
+ max_headroom += 8;
+ mtu -= 8;
+ }
+ if (mtu < IPV6_MIN_MTU)
+ mtu = IPV6_MIN_MTU;
+ if (skb_dst(skb))
+ skb_dst(skb)->ops->update_pmtu(skb_dst(skb), NULL, skb, mtu);
+ if (skb->len > mtu) {
+ *pmtu = mtu;
+ err = -EMSGSIZE;
+ goto tx_err_dst_release;
+ }
+
+ if (tunnel->err_count > 0) {
+ if (time_before(jiffies,
+ tunnel->err_time + IP6TUNNEL_ERR_TIMEO)) {
+ tunnel->err_count--;
+
+ dst_link_failure(skb);
+ } else
+ tunnel->err_count = 0;
+ }
+
+ max_headroom = LL_RESERVED_SPACE(tdev) + gre_hlen + dst->header_len;
+
+ if (skb_headroom(skb) < max_headroom || skb_shared(skb) ||
+ (skb_cloned(skb) && !skb_clone_writable(skb, 0))) {
+ new_skb = skb_realloc_headroom(skb, max_headroom);
+ if (max_headroom > dev->needed_headroom)
+ dev->needed_headroom = max_headroom;
+ if (!new_skb)
+ goto tx_err_dst_release;
+
+ if (skb->sk)
+ skb_set_owner_w(new_skb, skb->sk);
+ consume_skb(skb);
+ skb = new_skb;
+ }
+
+ skb_dst_drop(skb);
+
+ if (fl6->flowi6_mark) {
+ skb_dst_set(skb, dst);
+ ndst = NULL;
+ } else {
+ skb_dst_set_noref(skb, dst);
+ }
+
+ skb->transport_header = skb->network_header;
+
+ proto = NEXTHDR_GRE;
+ if (encap_limit >= 0) {
+ init_tel_txopt(&opt, encap_limit);
+ ipv6_push_nfrag_opts(skb, &opt.ops, &proto, NULL);
+ }
+
+ skb_push(skb, gre_hlen);
+ skb_reset_network_header(skb);
+
+ /*
+ * Push down and install the IP header.
+ */
+ ipv6h = ipv6_hdr(skb);
+ *(__be32 *)ipv6h = fl6->flowlabel | htonl(0x60000000);
+ dsfield = INET_ECN_encapsulate(0, dsfield);
+ ipv6_change_dsfield(ipv6h, ~INET_ECN_MASK, dsfield);
+ ipv6h->hop_limit = tunnel->parms.hop_limit;
+ ipv6h->nexthdr = proto;
+ ipv6h->saddr = fl6->saddr;
+ ipv6h->daddr = fl6->daddr;
+
+ ((__be16 *)(ipv6h + 1))[0] = tunnel->parms.o_flags;
+ ((__be16 *)(ipv6h + 1))[1] = (dev->type == ARPHRD_ETHER) ?
+ htons(ETH_P_TEB) : skb->protocol;
+
+ if (tunnel->parms.o_flags&(GRE_KEY|GRE_CSUM|GRE_SEQ)) {
+ __be32 *ptr = (__be32 *)(((u8 *)ipv6h) + tunnel->hlen - 4);
+
+ if (tunnel->parms.o_flags&GRE_SEQ) {
+ ++tunnel->o_seqno;
+ *ptr = htonl(tunnel->o_seqno);
+ ptr--;
+ }
+ if (tunnel->parms.o_flags&GRE_KEY) {
+ *ptr = tunnel->parms.o_key;
+ ptr--;
+ }
+ if (tunnel->parms.o_flags&GRE_CSUM) {
+ *ptr = 0;
+ *(__sum16 *)ptr = ip_compute_csum((void *)(ipv6h+1),
+ skb->len - sizeof(struct ipv6hdr));
+ }
+ }
+
+ nf_reset(skb);
+ pkt_len = skb->len;
+ err = ip6_local_out(skb);
+
+ if (net_xmit_eval(err) == 0) {
+ struct pcpu_tstats *tstats = this_cpu_ptr(tunnel->dev->tstats);
+
+ tstats->tx_bytes += pkt_len;
+ tstats->tx_packets++;
+ } else {
+ stats->tx_errors++;
+ stats->tx_aborted_errors++;
+ }
+
+ if (ndst)
+ ip6_tnl_dst_store(tunnel, ndst);
+
+ return 0;
+tx_err_link_failure:
+ stats->tx_carrier_errors++;
+ dst_link_failure(skb);
+tx_err_dst_release:
+ dst_release(ndst);
+ return err;
+}
+
+static inline int ip6gre_xmit_ipv4(struct sk_buff *skb, struct net_device *dev)
+{
+ struct ip6_tnl *t = netdev_priv(dev);
+ const struct iphdr *iph = ip_hdr(skb);
+ int encap_limit = -1;
+ struct flowi6 fl6;
+ __u8 dsfield;
+ __u32 mtu;
+ int err;
+
+ if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
+ encap_limit = t->parms.encap_limit;
+
+ memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6));
+ fl6.flowi6_proto = IPPROTO_IPIP;
+
+ dsfield = ipv4_get_dsfield(iph);
+
+ if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
+ fl6.flowlabel |= htonl((__u32)iph->tos << IPV6_TCLASS_SHIFT)
+ & IPV6_TCLASS_MASK;
+ if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
+ fl6.flowi6_mark = skb->mark;
+
+ err = ip6gre_xmit2(skb, dev, dsfield, &fl6, encap_limit, &mtu);
+ if (err != 0) {
+ /* XXX: send ICMP error even if DF is not set. */
+ if (err == -EMSGSIZE)
+ icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
+ htonl(mtu));
+ return -1;
+ }
+
+ return 0;
+}
+
+static inline int ip6gre_xmit_ipv6(struct sk_buff *skb, struct net_device *dev)
+{
+ struct ip6_tnl *t = netdev_priv(dev);
+ struct ipv6hdr *ipv6h = ipv6_hdr(skb);
+ int encap_limit = -1;
+ __u16 offset;
+ struct flowi6 fl6;
+ __u8 dsfield;
+ __u32 mtu;
+ int err;
+
+ if (ipv6_addr_equal(&t->parms.raddr, &ipv6h->saddr))
+ return -1;
+
+ offset = ip6_tnl_parse_tlv_enc_lim(skb, skb_network_header(skb));
+ if (offset > 0) {
+ struct ipv6_tlv_tnl_enc_lim *tel;
+ tel = (struct ipv6_tlv_tnl_enc_lim *)&skb_network_header(skb)[offset];
+ if (tel->encap_limit == 0) {
+ icmpv6_send(skb, ICMPV6_PARAMPROB,
+ ICMPV6_HDR_FIELD, offset + 2);
+ return -1;
+ }
+ encap_limit = tel->encap_limit - 1;
+ } else if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
+ encap_limit = t->parms.encap_limit;
+
+ memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6));
+ fl6.flowi6_proto = IPPROTO_IPV6;
+
+ dsfield = ipv6_get_dsfield(ipv6h);
+ if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
+ fl6.flowlabel |= (*(__be32 *) ipv6h & IPV6_TCLASS_MASK);
+ if (t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL)
+ fl6.flowlabel |= (*(__be32 *) ipv6h & IPV6_FLOWLABEL_MASK);
+ if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
+ fl6.flowi6_mark = skb->mark;
+
+ err = ip6gre_xmit2(skb, dev, dsfield, &fl6, encap_limit, &mtu);
+ if (err != 0) {
+ if (err == -EMSGSIZE)
+ icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
+ return -1;
+ }
+
+ return 0;
+}
+
+/**
+ * ip6_tnl_addr_conflict - compare packet addresses to tunnel's own
+ * @t: the outgoing tunnel device
+ * @hdr: IPv6 header from the incoming packet
+ *
+ * Description:
+ * Avoid trivial tunneling loop by checking that tunnel exit-point
+ * doesn't match source of incoming packet.
+ *
+ * Return:
+ * 1 if conflict,
+ * 0 else
+ **/
+
+static inline bool ip6gre_tnl_addr_conflict(const struct ip6_tnl *t,
+ const struct ipv6hdr *hdr)
+{
+ return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr);
+}
+
+static int ip6gre_xmit_other(struct sk_buff *skb, struct net_device *dev)
+{
+ struct ip6_tnl *t = netdev_priv(dev);
+ int encap_limit = -1;
+ struct flowi6 fl6;
+ __u32 mtu;
+ int err;
+
+ if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
+ encap_limit = t->parms.encap_limit;
+
+ memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6));
+ fl6.flowi6_proto = skb->protocol;
+
+ err = ip6gre_xmit2(skb, dev, 0, &fl6, encap_limit, &mtu);
+
+ return err;
+}
+
+static netdev_tx_t ip6gre_tunnel_xmit(struct sk_buff *skb,
+ struct net_device *dev)
+{
+ struct ip6_tnl *t = netdev_priv(dev);
+ struct net_device_stats *stats = &t->dev->stats;
+ int ret;
+
+ if (!ip6_tnl_xmit_ctl(t))
+ return -1;
+
+ switch (skb->protocol) {
+ case htons(ETH_P_IP):
+ ret = ip6gre_xmit_ipv4(skb, dev);
+ break;
+ case htons(ETH_P_IPV6):
+ ret = ip6gre_xmit_ipv6(skb, dev);
+ break;
+ default:
+ ret = ip6gre_xmit_other(skb, dev);
+ break;
+ }
+
+ if (ret < 0)
+ goto tx_err;
+
+ return NETDEV_TX_OK;
+
+tx_err:
+ stats->tx_errors++;
+ stats->tx_dropped++;
+ kfree_skb(skb);
+ return NETDEV_TX_OK;
+}
+
+static void ip6gre_tnl_link_config(struct ip6_tnl *t, int set_mtu)
+{
+ struct net_device *dev = t->dev;
+ struct __ip6_tnl_parm *p = &t->parms;
+ struct flowi6 *fl6 = &t->fl.u.ip6;
+ int addend = sizeof(struct ipv6hdr) + 4;
+
+ if (dev->type != ARPHRD_ETHER) {
+ memcpy(dev->dev_addr, &p->laddr, sizeof(struct in6_addr));
+ memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr));
+ }
+
+ /* Set up flowi template */
+ fl6->saddr = p->laddr;
+ fl6->daddr = p->raddr;
+ fl6->flowi6_oif = p->link;
+ fl6->flowlabel = 0;
+
+ if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS))
+ fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo;
+ if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL))
+ fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo;
+
+ p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV|IP6_TNL_F_CAP_PER_PACKET);
+ p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr);
+
+ if (p->flags&IP6_TNL_F_CAP_XMIT &&
+ p->flags&IP6_TNL_F_CAP_RCV && dev->type != ARPHRD_ETHER)
+ dev->flags |= IFF_POINTOPOINT;
+ else
+ dev->flags &= ~IFF_POINTOPOINT;
+
+ dev->iflink = p->link;
+
+ /* Precalculate GRE options length */
+ if (t->parms.o_flags&(GRE_CSUM|GRE_KEY|GRE_SEQ)) {
+ if (t->parms.o_flags&GRE_CSUM)
+ addend += 4;
+ if (t->parms.o_flags&GRE_KEY)
+ addend += 4;
+ if (t->parms.o_flags&GRE_SEQ)
+ addend += 4;
+ }
+
+ if (p->flags & IP6_TNL_F_CAP_XMIT) {
+ int strict = (ipv6_addr_type(&p->raddr) &
+ (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL));
+
+ struct rt6_info *rt = rt6_lookup(dev_net(dev),
+ &p->raddr, &p->laddr,
+ p->link, strict);
+
+ if (rt == NULL)
+ return;
+
+ if (rt->dst.dev) {
+ dev->hard_header_len = rt->dst.dev->hard_header_len + addend;
+
+ if (set_mtu) {
+ dev->mtu = rt->dst.dev->mtu - addend;
+ if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
+ dev->mtu -= 8;
+
+ if (dev->mtu < IPV6_MIN_MTU)
+ dev->mtu = IPV6_MIN_MTU;
+ }
+ }
+ dst_release(&rt->dst);
+ }
+
+ t->hlen = addend;
+}
+
+static int ip6gre_tnl_change(struct ip6_tnl *t,
+ const struct __ip6_tnl_parm *p, int set_mtu)
+{
+ t->parms.laddr = p->laddr;
+ t->parms.raddr = p->raddr;
+ t->parms.flags = p->flags;
+ t->parms.hop_limit = p->hop_limit;
+ t->parms.encap_limit = p->encap_limit;
+ t->parms.flowinfo = p->flowinfo;
+ t->parms.link = p->link;
+ t->parms.proto = p->proto;
+ t->parms.i_key = p->i_key;
+ t->parms.o_key = p->o_key;
+ t->parms.i_flags = p->i_flags;
+ t->parms.o_flags = p->o_flags;
+ ip6_tnl_dst_reset(t);
+ ip6gre_tnl_link_config(t, set_mtu);
+ return 0;
+}
+
+static void ip6gre_tnl_parm_from_user(struct __ip6_tnl_parm *p,
+ const struct ip6_tnl_parm2 *u)
+{
+ p->laddr = u->laddr;
+ p->raddr = u->raddr;
+ p->flags = u->flags;
+ p->hop_limit = u->hop_limit;
+ p->encap_limit = u->encap_limit;
+ p->flowinfo = u->flowinfo;
+ p->link = u->link;
+ p->i_key = u->i_key;
+ p->o_key = u->o_key;
+ p->i_flags = u->i_flags;
+ p->o_flags = u->o_flags;
+ memcpy(p->name, u->name, sizeof(u->name));
+}
+
+static void ip6gre_tnl_parm_to_user(struct ip6_tnl_parm2 *u,
+ const struct __ip6_tnl_parm *p)
+{
+ u->proto = IPPROTO_GRE;
+ u->laddr = p->laddr;
+ u->raddr = p->raddr;
+ u->flags = p->flags;
+ u->hop_limit = p->hop_limit;
+ u->encap_limit = p->encap_limit;
+ u->flowinfo = p->flowinfo;
+ u->link = p->link;
+ u->i_key = p->i_key;
+ u->o_key = p->o_key;
+ u->i_flags = p->i_flags;
+ u->o_flags = p->o_flags;
+ memcpy(u->name, p->name, sizeof(u->name));
+}
+
+static int ip6gre_tunnel_ioctl(struct net_device *dev,
+ struct ifreq *ifr, int cmd)
+{
+ int err = 0;
+ struct ip6_tnl_parm2 p;
+ struct __ip6_tnl_parm p1;
+ struct ip6_tnl *t;
+ struct net *net = dev_net(dev);
+ struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
+
+ switch (cmd) {
+ case SIOCGETTUNNEL:
+ t = NULL;
+ if (dev == ign->fb_tunnel_dev) {
+ if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) {
+ err = -EFAULT;
+ break;
+ }
+ ip6gre_tnl_parm_from_user(&p1, &p);
+ t = ip6gre_tunnel_locate(net, &p1, 0);
+ }
+ if (t == NULL)
+ t = netdev_priv(dev);
+ ip6gre_tnl_parm_to_user(&p, &t->parms);
+ if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
+ err = -EFAULT;
+ break;
+
+ case SIOCADDTUNNEL:
+ case SIOCCHGTUNNEL:
+ err = -EPERM;
+ if (!capable(CAP_NET_ADMIN))
+ goto done;
+
+ err = -EFAULT;
+ if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
+ goto done;
+
+ err = -EINVAL;
+ if ((p.i_flags|p.o_flags)&(GRE_VERSION|GRE_ROUTING))
+ goto done;
+
+ if (!(p.i_flags&GRE_KEY))
+ p.i_key = 0;
+ if (!(p.o_flags&GRE_KEY))
+ p.o_key = 0;
+
+ ip6gre_tnl_parm_from_user(&p1, &p);
+ t = ip6gre_tunnel_locate(net, &p1, cmd == SIOCADDTUNNEL);
+
+ if (dev != ign->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
+ if (t != NULL) {
+ if (t->dev != dev) {
+ err = -EEXIST;
+ break;
+ }
+ } else {
+ t = netdev_priv(dev);
+
+ ip6gre_tunnel_unlink(ign, t);
+ synchronize_net();
+ ip6gre_tnl_change(t, &p1, 1);
+ ip6gre_tunnel_link(ign, t);
+ netdev_state_change(dev);
+ }
+ }
+
+ if (t) {
+ err = 0;
+
+ ip6gre_tnl_parm_to_user(&p, &t->parms);
+ if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
+ err = -EFAULT;
+ } else
+ err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
+ break;
+
+ case SIOCDELTUNNEL:
+ err = -EPERM;
+ if (!capable(CAP_NET_ADMIN))
+ goto done;
+
+ if (dev == ign->fb_tunnel_dev) {
+ err = -EFAULT;
+ if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
+ goto done;
+ err = -ENOENT;
+ ip6gre_tnl_parm_from_user(&p1, &p);
+ t = ip6gre_tunnel_locate(net, &p1, 0);
+ if (t == NULL)
+ goto done;
+ err = -EPERM;
+ if (t == netdev_priv(ign->fb_tunnel_dev))
+ goto done;
+ dev = t->dev;
+ }
+ unregister_netdevice(dev);
+ err = 0;
+ break;
+
+ default:
+ err = -EINVAL;
+ }
+
+done:
+ return err;
+}
+
+static int ip6gre_tunnel_change_mtu(struct net_device *dev, int new_mtu)
+{
+ struct ip6_tnl *tunnel = netdev_priv(dev);
+ if (new_mtu < 68 ||
+ new_mtu > 0xFFF8 - dev->hard_header_len - tunnel->hlen)
+ return -EINVAL;
+ dev->mtu = new_mtu;
+ return 0;
+}
+
+static int ip6gre_header(struct sk_buff *skb, struct net_device *dev,
+ unsigned short type,
+ const void *daddr, const void *saddr, unsigned int len)
+{
+ struct ip6_tnl *t = netdev_priv(dev);
+ struct ipv6hdr *ipv6h = (struct ipv6hdr *)skb_push(skb, t->hlen);
+ __be16 *p = (__be16 *)(ipv6h+1);
+
+ *(__be32 *)ipv6h = t->fl.u.ip6.flowlabel | htonl(0x60000000);
+ ipv6h->hop_limit = t->parms.hop_limit;
+ ipv6h->nexthdr = NEXTHDR_GRE;
+ ipv6h->saddr = t->parms.laddr;
+ ipv6h->daddr = t->parms.raddr;
+
+ p[0] = t->parms.o_flags;
+ p[1] = htons(type);
+
+ /*
+ * Set the source hardware address.
+ */
+
+ if (saddr)
+ memcpy(&ipv6h->saddr, saddr, sizeof(struct in6_addr));
+ if (daddr)
+ memcpy(&ipv6h->daddr, daddr, sizeof(struct in6_addr));
+ if (!ipv6_addr_any(&ipv6h->daddr))
+ return t->hlen;
+
+ return -t->hlen;
+}
+
+static int ip6gre_header_parse(const struct sk_buff *skb, unsigned char *haddr)
+{
+ const struct ipv6hdr *ipv6h = (const struct ipv6hdr *)skb_mac_header(skb);
+ memcpy(haddr, &ipv6h->saddr, sizeof(struct in6_addr));
+ return sizeof(struct in6_addr);
+}
+
+static const struct header_ops ip6gre_header_ops = {
+ .create = ip6gre_header,
+ .parse = ip6gre_header_parse,
+};
+
+static const struct net_device_ops ip6gre_netdev_ops = {
+ .ndo_init = ip6gre_tunnel_init,
+ .ndo_uninit = ip6gre_tunnel_uninit,
+ .ndo_start_xmit = ip6gre_tunnel_xmit,
+ .ndo_do_ioctl = ip6gre_tunnel_ioctl,
+ .ndo_change_mtu = ip6gre_tunnel_change_mtu,
+ .ndo_get_stats64 = ip6gre_get_stats64,
+};
+
+static void ip6gre_dev_free(struct net_device *dev)
+{
+ free_percpu(dev->tstats);
+ free_netdev(dev);
+}
+
+static void ip6gre_tunnel_setup(struct net_device *dev)
+{
+ struct ip6_tnl *t;
+
+ dev->netdev_ops = &ip6gre_netdev_ops;
+ dev->destructor = ip6gre_dev_free;
+
+ dev->type = ARPHRD_IP6GRE;
+ dev->hard_header_len = LL_MAX_HEADER + sizeof(struct ipv6hdr) + 4;
+ dev->mtu = ETH_DATA_LEN - sizeof(struct ipv6hdr) - 4;
+ t = netdev_priv(dev);
+ if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
+ dev->mtu -= 8;
+ dev->flags |= IFF_NOARP;
+ dev->iflink = 0;
+ dev->addr_len = sizeof(struct in6_addr);
+ dev->features |= NETIF_F_NETNS_LOCAL;
+ dev->priv_flags &= ~IFF_XMIT_DST_RELEASE;
+}
+
+static int ip6gre_tunnel_init(struct net_device *dev)
+{
+ struct ip6_tnl *tunnel;
+
+ tunnel = netdev_priv(dev);
+
+ tunnel->dev = dev;
+ strcpy(tunnel->parms.name, dev->name);
+
+ memcpy(dev->dev_addr, &tunnel->parms.laddr, sizeof(struct in6_addr));
+ memcpy(dev->broadcast, &tunnel->parms.raddr, sizeof(struct in6_addr));
+
+ if (ipv6_addr_any(&tunnel->parms.raddr))
+ dev->header_ops = &ip6gre_header_ops;
+
+ dev->tstats = alloc_percpu(struct pcpu_tstats);
+ if (!dev->tstats)
+ return -ENOMEM;
+
+ return 0;
+}
+
+static void ip6gre_fb_tunnel_init(struct net_device *dev)
+{
+ struct ip6_tnl *tunnel = netdev_priv(dev);
+
+ tunnel->dev = dev;
+ strcpy(tunnel->parms.name, dev->name);
+
+ tunnel->hlen = sizeof(struct ipv6hdr) + 4;
+
+ dev_hold(dev);
+}
+
+
+static struct inet6_protocol ip6gre_protocol __read_mostly = {
+ .handler = ip6gre_rcv,
+ .err_handler = ip6gre_err,
+ .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
+};
+
+static void ip6gre_destroy_tunnels(struct ip6gre_net *ign,
+ struct list_head *head)
+{
+ int prio;
+
+ for (prio = 0; prio < 4; prio++) {
+ int h;
+ for (h = 0; h < HASH_SIZE; h++) {
+ struct ip6_tnl *t;
+
+ t = rtnl_dereference(ign->tunnels[prio][h]);
+
+ while (t != NULL) {
+ unregister_netdevice_queue(t->dev, head);
+ t = rtnl_dereference(t->next);
+ }
+ }
+ }
+}
+
+static int __net_init ip6gre_init_net(struct net *net)
+{
+ struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
+ int err;
+
+ ign->fb_tunnel_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6gre0",
+ ip6gre_tunnel_setup);
+ if (!ign->fb_tunnel_dev) {
+ err = -ENOMEM;
+ goto err_alloc_dev;
+ }
+ dev_net_set(ign->fb_tunnel_dev, net);
+
+ ip6gre_fb_tunnel_init(ign->fb_tunnel_dev);
+ ign->fb_tunnel_dev->rtnl_link_ops = &ip6gre_link_ops;
+
+ err = register_netdev(ign->fb_tunnel_dev);
+ if (err)
+ goto err_reg_dev;
+
+ rcu_assign_pointer(ign->tunnels_wc[0],
+ netdev_priv(ign->fb_tunnel_dev));
+ return 0;
+
+err_reg_dev:
+ ip6gre_dev_free(ign->fb_tunnel_dev);
+err_alloc_dev:
+ return err;
+}
+
+static void __net_exit ip6gre_exit_net(struct net *net)
+{
+ struct ip6gre_net *ign;
+ LIST_HEAD(list);
+
+ ign = net_generic(net, ip6gre_net_id);
+ rtnl_lock();
+ ip6gre_destroy_tunnels(ign, &list);
+ unregister_netdevice_many(&list);
+ rtnl_unlock();
+}
+
+static struct pernet_operations ip6gre_net_ops = {
+ .init = ip6gre_init_net,
+ .exit = ip6gre_exit_net,
+ .id = &ip6gre_net_id,
+ .size = sizeof(struct ip6gre_net),
+};
+
+static int ip6gre_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 ip6gre_tap_validate(struct nlattr *tb[], struct nlattr *data[])
+{
+ struct in6_addr 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]) {
+ nla_memcpy(&daddr, data[IFLA_GRE_REMOTE], sizeof(struct in6_addr));
+ if (ipv6_addr_any(&daddr))
+ return -EINVAL;
+ }
+
+out:
+ return ip6gre_tunnel_validate(tb, data);
+}
+
+
+static void ip6gre_netlink_parms(struct nlattr *data[],
+ struct __ip6_tnl_parm *parms)
+{
+ memset(parms, 0, sizeof(*parms));
+
+ if (!data)
+ return;
+
+ if (data[IFLA_GRE_LINK])
+ parms->link = nla_get_u32(data[IFLA_GRE_LINK]);
+
+ if (data[IFLA_GRE_IFLAGS])
+ parms->i_flags = nla_get_be16(data[IFLA_GRE_IFLAGS]);
+
+ if (data[IFLA_GRE_OFLAGS])
+ parms->o_flags = nla_get_be16(data[IFLA_GRE_OFLAGS]);
+
+ if (data[IFLA_GRE_IKEY])
+ parms->i_key = nla_get_be32(data[IFLA_GRE_IKEY]);
+
+ if (data[IFLA_GRE_OKEY])
+ parms->o_key = nla_get_be32(data[IFLA_GRE_OKEY]);
+
+ if (data[IFLA_GRE_LOCAL])
+ nla_memcpy(&parms->laddr, data[IFLA_GRE_LOCAL], sizeof(struct in6_addr));
+
+ if (data[IFLA_GRE_REMOTE])
+ nla_memcpy(&parms->raddr, data[IFLA_GRE_REMOTE], sizeof(struct in6_addr));
+
+ if (data[IFLA_GRE_TTL])
+ parms->hop_limit = nla_get_u8(data[IFLA_GRE_TTL]);
+
+ if (data[IFLA_GRE_ENCAP_LIMIT])
+ parms->encap_limit = nla_get_u8(data[IFLA_GRE_ENCAP_LIMIT]);
+
+ if (data[IFLA_GRE_FLOWINFO])
+ parms->flowinfo = nla_get_u32(data[IFLA_GRE_FLOWINFO]);
+
+ if (data[IFLA_GRE_FLAGS])
+ parms->flags = nla_get_u32(data[IFLA_GRE_FLAGS]);
+}
+
+static int ip6gre_tap_init(struct net_device *dev)
+{
+ struct ip6_tnl *tunnel;
+
+ tunnel = netdev_priv(dev);
+
+ tunnel->dev = dev;
+ strcpy(tunnel->parms.name, dev->name);
+
+ ip6gre_tnl_link_config(tunnel, 1);
+
+ dev->tstats = alloc_percpu(struct pcpu_tstats);
+ if (!dev->tstats)
+ return -ENOMEM;
+
+ return 0;
+}
+
+static const struct net_device_ops ip6gre_tap_netdev_ops = {
+ .ndo_init = ip6gre_tap_init,
+ .ndo_uninit = ip6gre_tunnel_uninit,
+ .ndo_start_xmit = ip6gre_tunnel_xmit,
+ .ndo_set_mac_address = eth_mac_addr,
+ .ndo_validate_addr = eth_validate_addr,
+ .ndo_change_mtu = ip6gre_tunnel_change_mtu,
+ .ndo_get_stats64 = ip6gre_get_stats64,
+};
+
+static void ip6gre_tap_setup(struct net_device *dev)
+{
+
+ ether_setup(dev);
+
+ dev->netdev_ops = &ip6gre_tap_netdev_ops;
+ dev->destructor = ip6gre_dev_free;
+
+ dev->iflink = 0;
+ dev->features |= NETIF_F_NETNS_LOCAL;
+}
+
+static int ip6gre_newlink(struct net *src_net, struct net_device *dev,
+ struct nlattr *tb[], struct nlattr *data[])
+{
+ struct ip6_tnl *nt;
+ struct net *net = dev_net(dev);
+ struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
+ int err;
+
+ nt = netdev_priv(dev);
+ ip6gre_netlink_parms(data, &nt->parms);
+
+ if (ip6gre_tunnel_find(net, &nt->parms, dev->type))
+ return -EEXIST;
+
+ if (dev->type == ARPHRD_ETHER && !tb[IFLA_ADDRESS])
+ eth_hw_addr_random(dev);
+
+ nt->dev = dev;
+ ip6gre_tnl_link_config(nt, !tb[IFLA_MTU]);
+
+ /* Can use a lockless transmit, unless we generate output sequences */
+ if (!(nt->parms.o_flags & GRE_SEQ))
+ dev->features |= NETIF_F_LLTX;
+
+ err = register_netdevice(dev);
+ if (err)
+ goto out;
+
+ dev_hold(dev);
+ ip6gre_tunnel_link(ign, nt);
+
+out:
+ return err;
+}
+
+static int ip6gre_changelink(struct net_device *dev, struct nlattr *tb[],
+ struct nlattr *data[])
+{
+ struct ip6_tnl *t, *nt;
+ struct net *net = dev_net(dev);
+ struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
+ struct __ip6_tnl_parm p;
+
+ if (dev == ign->fb_tunnel_dev)
+ return -EINVAL;
+
+ nt = netdev_priv(dev);
+ ip6gre_netlink_parms(data, &p);
+
+ t = ip6gre_tunnel_locate(net, &p, 0);
+
+ if (t) {
+ if (t->dev != dev)
+ return -EEXIST;
+ } else {
+ t = nt;
+
+ ip6gre_tunnel_unlink(ign, t);
+ ip6gre_tnl_change(t, &p, !tb[IFLA_MTU]);
+ ip6gre_tunnel_link(ign, t);
+ netdev_state_change(dev);
+ }
+
+ return 0;
+}
+
+static size_t ip6gre_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_ENCAP_LIMIT */
+ nla_total_size(1) +
+ /* IFLA_GRE_FLOWINFO */
+ nla_total_size(4) +
+ /* IFLA_GRE_FLAGS */
+ nla_total_size(4) +
+ 0;
+}
+
+static int ip6gre_fill_info(struct sk_buff *skb, const struct net_device *dev)
+{
+ struct ip6_tnl *t = netdev_priv(dev);
+ struct __ip6_tnl_parm *p = &t->parms;
+
+ if (nla_put_u32(skb, IFLA_GRE_LINK, p->link) ||
+ nla_put_be16(skb, IFLA_GRE_IFLAGS, p->i_flags) ||
+ nla_put_be16(skb, IFLA_GRE_OFLAGS, p->o_flags) ||
+ nla_put_be32(skb, IFLA_GRE_IKEY, p->i_key) ||
+ nla_put_be32(skb, IFLA_GRE_OKEY, p->o_key) ||
+ nla_put(skb, IFLA_GRE_LOCAL, sizeof(struct in6_addr), &p->raddr) ||
+ nla_put(skb, IFLA_GRE_REMOTE, sizeof(struct in6_addr), &p->laddr) ||
+ nla_put_u8(skb, IFLA_GRE_TTL, p->hop_limit) ||
+ /*nla_put_u8(skb, IFLA_GRE_TOS, t->priority) ||*/
+ nla_put_u8(skb, IFLA_GRE_ENCAP_LIMIT, p->encap_limit) ||
+ nla_put_be32(skb, IFLA_GRE_FLOWINFO, p->flowinfo) ||
+ nla_put_u32(skb, IFLA_GRE_FLAGS, p->flags))
+ goto nla_put_failure;
+ return 0;
+
+nla_put_failure:
+ return -EMSGSIZE;
+}
+
+static const struct nla_policy ip6gre_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 ipv6hdr, saddr) },
+ [IFLA_GRE_REMOTE] = { .len = FIELD_SIZEOF(struct ipv6hdr, daddr) },
+ [IFLA_GRE_TTL] = { .type = NLA_U8 },
+ [IFLA_GRE_ENCAP_LIMIT] = { .type = NLA_U8 },
+ [IFLA_GRE_FLOWINFO] = { .type = NLA_U32 },
+ [IFLA_GRE_FLAGS] = { .type = NLA_U32 },
+};
+
+static struct rtnl_link_ops ip6gre_link_ops __read_mostly = {
+ .kind = "ip6gre",
+ .maxtype = IFLA_GRE_MAX,
+ .policy = ip6gre_policy,
+ .priv_size = sizeof(struct ip6_tnl),
+ .setup = ip6gre_tunnel_setup,
+ .validate = ip6gre_tunnel_validate,
+ .newlink = ip6gre_newlink,
+ .changelink = ip6gre_changelink,
+ .get_size = ip6gre_get_size,
+ .fill_info = ip6gre_fill_info,
+};
+
+static struct rtnl_link_ops ip6gre_tap_ops __read_mostly = {
+ .kind = "ip6gretap",
+ .maxtype = IFLA_GRE_MAX,
+ .policy = ip6gre_policy,
+ .priv_size = sizeof(struct ip6_tnl),
+ .setup = ip6gre_tap_setup,
+ .validate = ip6gre_tap_validate,
+ .newlink = ip6gre_newlink,
+ .changelink = ip6gre_changelink,
+ .get_size = ip6gre_get_size,
+ .fill_info = ip6gre_fill_info,
+};
+
+/*
+ * And now the modules code and kernel interface.
+ */
+
+static int __init ip6gre_init(void)
+{
+ int err;
+
+ pr_info("GRE over IPv6 tunneling driver\n");
+
+ err = register_pernet_device(&ip6gre_net_ops);
+ if (err < 0)
+ return err;
+
+ err = inet6_add_protocol(&ip6gre_protocol, IPPROTO_GRE);
+ if (err < 0) {
+ pr_info("%s: can't add protocol\n", __func__);
+ goto add_proto_failed;
+ }
+
+ err = rtnl_link_register(&ip6gre_link_ops);
+ if (err < 0)
+ goto rtnl_link_failed;
+
+ err = rtnl_link_register(&ip6gre_tap_ops);
+ if (err < 0)
+ goto tap_ops_failed;
+
+out:
+ return err;
+
+tap_ops_failed:
+ rtnl_link_unregister(&ip6gre_link_ops);
+rtnl_link_failed:
+ inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE);
+add_proto_failed:
+ unregister_pernet_device(&ip6gre_net_ops);
+ goto out;
+}
+
+static void __exit ip6gre_fini(void)
+{
+ rtnl_link_unregister(&ip6gre_tap_ops);
+ rtnl_link_unregister(&ip6gre_link_ops);
+ inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE);
+ unregister_pernet_device(&ip6gre_net_ops);
+}
+
+module_init(ip6gre_init);
+module_exit(ip6gre_fini);
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("D. Kozlov (xeb@mail.ru)");
+MODULE_DESCRIPTION("GRE over IPv6 tunneling device");
+MODULE_ALIAS_RTNL_LINK("ip6gre");
+MODULE_ALIAS_NETDEV("ip6gre0");
