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 #define TUNNEL_DONT_FRAGMENT    __cpu_to_be16(0x0100)
  77
  78 struct tnl_ptk_info {
  79         __be16 flags;
  80         __be16 proto;
  81         __be32 key;
  82         __be32 seq;
  83 };
  84
  85 #define PACKET_RCVD     0
  86 #define PACKET_REJECT   1
  87
  88 #define IP_TNL_HASH_BITS   10
  89 #define IP_TNL_HASH_SIZE   (1 << IP_TNL_HASH_BITS)
  90
  91 struct ip_tunnel_net {
  92         struct hlist_head *tunnels;
  93         struct net_device *fb_tunnel_dev;
  94 };
  95
  96 #ifdef CONFIG_INET
  97
  98 int ip_tunnel_init(struct net_device *dev);
  99 void ip_tunnel_uninit(struct net_device *dev);
 100 void  ip_tunnel_dellink(struct net_device *dev, struct list_head *head);
 101 int ip_tunnel_init_net(struct net *net, int ip_tnl_net_id,
 102                        struct rtnl_link_ops *ops, char *devname);
 103
 104 void ip_tunnel_delete_net(struct ip_tunnel_net *itn);
 105
 106 void ip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev,
 107                     const struct iphdr *tnl_params, const u8 protocol);
 108 int ip_tunnel_ioctl(struct net_device *dev, struct ip_tunnel_parm *p, int cmd);
 109 int ip_tunnel_change_mtu(struct net_device *dev, int new_mtu);
 110
 111 struct rtnl_link_stats64 *ip_tunnel_get_stats64(struct net_device *dev,
 112                                                 struct rtnl_link_stats64 *tot);
 113 struct ip_tunnel *ip_tunnel_lookup(struct ip_tunnel_net *itn,
 114                                    int link, __be16 flags,
 115                                    __be32 remote, __be32 local,
 116                                    __be32 key);
 117
 118 int ip_tunnel_rcv(struct ip_tunnel *tunnel, struct sk_buff *skb,
 119                   const struct tnl_ptk_info *tpi, bool log_ecn_error);
 120 int ip_tunnel_changelink(struct net_device *dev, struct nlattr *tb[],
 121                          struct ip_tunnel_parm *p);
 122 int ip_tunnel_newlink(struct net_device *dev, struct nlattr *tb[],
 123                       struct ip_tunnel_parm *p);
 124 void ip_tunnel_setup(struct net_device *dev, int net_id);
 125
 126 /* Extract dsfield from inner protocol */
 127 static inline u8 ip_tunnel_get_dsfield(const struct iphdr *iph,
 128                                        const struct sk_buff *skb)
 129 {
 130         if (skb->protocol == htons(ETH_P_IP))
 131                 return iph->tos;
 132         else if (skb->protocol == htons(ETH_P_IPV6))
 133                 return ipv6_get_dsfield((const struct ipv6hdr *)iph);
 134         else
 135                 return 0;
 136 }
 137
 138 /* Propogate ECN bits out */
 139 static inline u8 ip_tunnel_ecn_encap(u8 tos, const struct iphdr *iph,
 140                                      const struct sk_buff *skb)
 141 {
 142         u8 inner = ip_tunnel_get_dsfield(iph, skb);
 143
 144         return INET_ECN_encapsulate(tos, inner);
 145 }
 146
 147 static inline void tunnel_ip_select_ident(struct sk_buff *skb,
 148                                           const struct iphdr  *old_iph,
 149                                           struct dst_entry *dst)
 150 {
 151         struct iphdr *iph = ip_hdr(skb);
 152
 153         /* Use inner packet iph-id if possible. */
 154         if (skb->protocol == htons(ETH_P_IP) && old_iph->id)
 155                 iph->id = old_iph->id;
 156         else
 157                 __ip_select_ident(iph, dst,
 158                                   (skb_shinfo(skb)->gso_segs ?: 1) - 1);
 159 }
 160
 161 int iptunnel_pull_header(struct sk_buff *skb, int hdr_len, __be16 inner_proto);
 162 int iptunnel_xmit(struct net *net, struct rtable *rt,
 163                   struct sk_buff *skb,
 164                   __be32 src, __be32 dst, __u8 proto,
 165                   __u8 tos, __u8 ttl, __be16 df);
 166
 167 static inline void iptunnel_xmit_stats(int err,
 168                                        struct net_device_stats *err_stats,
 169                                        struct pcpu_tstats __percpu *stats)
 170 {
 171         if (err > 0) {
 172                 struct pcpu_tstats *tstats = this_cpu_ptr(stats);
 173
 174                 u64_stats_update_begin(&tstats->syncp);
 175                 tstats->tx_bytes += err;
 176                 tstats->tx_packets++;
 177                 u64_stats_update_end(&tstats->syncp);
 178         } else if (err < 0) {
 179                 err_stats->tx_errors++;
 180                 err_stats->tx_aborted_errors++;
 181         } else {
 182                 err_stats->tx_dropped++;
 183         }
 184 }
 185
 186 #endif /* CONFIG_INET */
 187
 188 #endif /* __NET_IP_TUNNELS_H */