include/net/ip_tunnels.h

   1 #ifndef __NET_IP_TUNNELS_H
   2 #define __NET_IP_TUNNELS_H 1
   3
   4 #include <linux/if_tunnel.h>
   5 #include <linux/netdevice.h>
   6 #include <linux/skbuff.h>
   7 #include <linux/types.h>
   8 #include <linux/u64_stats_sync.h>
   9 #include <net/dsfield.h>
  10 #include <net/gro_cells.h>
  11 #include <net/inet_ecn.h>
  12 #include <net/ip.h>
  13 #include <net/rtnetlink.h>
  14
  15 #if IS_ENABLED(CONFIG_IPV6)
  16 #include <net/ipv6.h>
  17 #include <net/ip6_fib.h>
  18 #include <net/ip6_route.h>
  19 #endif
  20
  21 /* Keep error state on tunnel for 30 sec */
  22 #define IPTUNNEL_ERR_TIMEO      (30*HZ)
  23
  24 /* 6rd prefix/relay information */
  25 #ifdef CONFIG_IPV6_SIT_6RD
  26 struct ip_tunnel_6rd_parm {
  27         struct in6_addr         prefix;
  28         __be32                  relay_prefix;
  29         u16                     prefixlen;
  30         u16                     relay_prefixlen;
  31 };
  32 #endif
  33
  34 struct ip_tunnel_prl_entry {
  35         struct ip_tunnel_prl_entry __rcu *next;
  36         __be32                          addr;
  37         u16                             flags;
  38         struct rcu_head                 rcu_head;
  39 };
  40
  41 struct ip_tunnel {
  42         struct ip_tunnel __rcu  *next;
  43         struct hlist_node hash_node;
  44         struct net_device       *dev;
  45
  46         int             err_count;      /* Number of arrived ICMP errors */
  47         unsigned long   err_time;       /* Time when the last ICMP error
  48                                          * arrived */
  49
  50         /* These four fields used only by GRE */
  51         __u32           i_seqno;        /* The last seen seqno  */
  52         __u32           o_seqno;        /* The last output seqno */
  53         int             hlen;           /* Precalculated header length */
  54         int             mlink;
  55
  56         struct ip_tunnel_parm parms;
  57
  58         /* for SIT */
  59 #ifdef CONFIG_IPV6_SIT_6RD
  60         struct ip_tunnel_6rd_parm ip6rd;
  61 #endif
  62         struct ip_tunnel_prl_entry __rcu *prl;  /* potential router list */
  63         unsigned int            prl_count;      /* # of entries in PRL */
  64         int                     ip_tnl_net_id;
  65         struct gro_cells        gro_cells;
  66 };
  67
  68 #define TUNNEL_CSUM     __cpu_to_be16(0x01)
  69 #define TUNNEL_ROUTING  __cpu_to_be16(0x02)
  70 #define TUNNEL_KEY      __cpu_to_be16(0x04)
  71 #define TUNNEL_SEQ      __cpu_to_be16(0x08)
  72 #define TUNNEL_STRICT   __cpu_to_be16(0x10)
  73 #define TUNNEL_REC      __cpu_to_be16(0x20)
  74 #define TUNNEL_VERSION  __cpu_to_be16(0x40)
  75 #define TUNNEL_NO_KEY   __cpu_to_be16(0x80)
  76
  77 struct tnl_ptk_info {
  78         __be16 flags;
  79         __be16 proto;
  80         __be32 key;
  81         __be32 seq;
  82 };
  83
  84 #define PACKET_RCVD     0
  85 #define PACKET_REJECT   1
  86
  87 #define IP_TNL_HASH_BITS   10
  88 #define IP_TNL_HASH_SIZE   (1 << IP_TNL_HASH_BITS)
  89
  90 struct ip_tunnel_net {
  91         struct hlist_head *tunnels;
  92         struct net_device *fb_tunnel_dev;
  93 };
  94
  95 int ip_tunnel_init(struct net_device *dev);
  96 void ip_tunnel_uninit(struct net_device *dev);
  97 void  ip_tunnel_dellink(struct net_device *dev, struct list_head *head);
  98 int __net_init ip_tunnel_init_net(struct net *net, int ip_tnl_net_id,
  99                                   struct rtnl_link_ops *ops, char *devname);
 100
 101 void __net_exit ip_tunnel_delete_net(struct ip_tunnel_net *itn);
 102
 103 void ip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev,
 104                     const struct iphdr *tnl_params);
 105 int ip_tunnel_ioctl(struct net_device *dev, struct ip_tunnel_parm *p, int cmd);
 106 int ip_tunnel_change_mtu(struct net_device *dev, int new_mtu);
 107
 108 struct rtnl_link_stats64 *ip_tunnel_get_stats64(struct net_device *dev,
 109                                                 struct rtnl_link_stats64 *tot);
 110 struct ip_tunnel *ip_tunnel_lookup(struct ip_tunnel_net *itn,
 111                                    int link, __be16 flags,
 112                                    __be32 remote, __be32 local,
 113                                    __be32 key);
 114
 115 int ip_tunnel_rcv(struct ip_tunnel *tunnel, struct sk_buff *skb,
 116                   const struct tnl_ptk_info *tpi, bool log_ecn_error);
 117 int ip_tunnel_changelink(struct net_device *dev, struct nlattr *tb[],
 118                          struct ip_tunnel_parm *p);
 119 int ip_tunnel_newlink(struct net_device *dev, struct nlattr *tb[],
 120                       struct ip_tunnel_parm *p);
 121 void ip_tunnel_setup(struct net_device *dev, int net_id);
 122
 123 /* Extract dsfield from inner protocol */
 124 static inline u8 ip_tunnel_get_dsfield(const struct iphdr *iph,
 125                                        const struct sk_buff *skb)
 126 {
 127         if (skb->protocol == htons(ETH_P_IP))
 128                 return iph->tos;
 129         else if (skb->protocol == htons(ETH_P_IPV6))
 130                 return ipv6_get_dsfield((const struct ipv6hdr *)iph);
 131         else
 132                 return 0;
 133 }
 134
 135 /* Propogate ECN bits out */
 136 static inline u8 ip_tunnel_ecn_encap(u8 tos, const struct iphdr *iph,
 137                                      const struct sk_buff *skb)
 138 {
 139         u8 inner = ip_tunnel_get_dsfield(iph, skb);
 140
 141         return INET_ECN_encapsulate(tos, inner);
 142 }
 143
 144 static inline void tunnel_ip_select_ident(struct sk_buff *skb,
 145                                           const struct iphdr  *old_iph,
 146                                           struct dst_entry *dst)
 147 {
 148         struct iphdr *iph = ip_hdr(skb);
 149
 150         /* Use inner packet iph-id if possible. */
 151         if (skb->protocol == htons(ETH_P_IP) && old_iph->id)
 152                 iph->id = old_iph->id;
 153         else
 154                 __ip_select_ident(iph, dst,
 155                                   (skb_shinfo(skb)->gso_segs ?: 1) - 1);
 156 }
 157
 158 static inline void iptunnel_xmit(struct sk_buff *skb, struct net_device *dev)
 159 {
 160         int err;
 161         int pkt_len = skb->len - skb_transport_offset(skb);
 162         struct pcpu_tstats *tstats = this_cpu_ptr(dev->tstats);
 163
 164         nf_reset(skb);
 165
 166         err = ip_local_out(skb);
 167         if (likely(net_xmit_eval(err) == 0)) {
 168                 u64_stats_update_begin(&tstats->syncp);
 169                 tstats->tx_bytes += pkt_len;
 170                 tstats->tx_packets++;
 171                 u64_stats_update_end(&tstats->syncp);
 172         } else {
 173                 dev->stats.tx_errors++;
 174                 dev->stats.tx_aborted_errors++;
 175         }
 176 }
 177 #endif /* __NET_IP_TUNNELS_H */