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/netns/generic.h>
  14 #include <net/rtnetlink.h>
  15
  16 #if IS_ENABLED(CONFIG_IPV6)
  17 #include <net/ipv6.h>
  18 #include <net/ip6_fib.h>
  19 #include <net/ip6_route.h>
  20 #endif
  21
  22 /* Keep error state on tunnel for 30 sec */
  23 #define IPTUNNEL_ERR_TIMEO      (30*HZ)
  24
  25 /* 6rd prefix/relay information */
  26 #ifdef CONFIG_IPV6_SIT_6RD
  27 struct ip_tunnel_6rd_parm {
  28         struct in6_addr         prefix;
  29         __be32                  relay_prefix;
  30         u16                     prefixlen;
  31         u16                     relay_prefixlen;
  32 };
  33 #endif
  34
  35 struct ip_tunnel_encap {
  36         __u16                   type;
  37         __u16                   flags;
  38         __be16                  sport;
  39         __be16                  dport;
  40 };
  41
  42 struct ip_tunnel_prl_entry {
  43         struct ip_tunnel_prl_entry __rcu *next;
  44         __be32                          addr;
  45         u16                             flags;
  46         struct rcu_head                 rcu_head;
  47 };
  48
  49 struct ip_tunnel_dst {
  50         struct dst_entry __rcu          *dst;
  51         __be32                           saddr;
  52 };
  53
  54 struct ip_tunnel {
  55         struct ip_tunnel __rcu  *next;
  56         struct hlist_node hash_node;
  57         struct net_device       *dev;
  58         struct net              *net;   /* netns for packet i/o */
  59
  60         int             err_count;      /* Number of arrived ICMP errors */
  61         unsigned long   err_time;       /* Time when the last ICMP error
  62                                          * arrived */
  63
  64         /* These four fields used only by GRE */
  65         __u32           i_seqno;        /* The last seen seqno  */
  66         __u32           o_seqno;        /* The last output seqno */
  67         int             tun_hlen;       /* Precalculated header length */
  68         int             mlink;
  69
  70         struct ip_tunnel_dst __percpu *dst_cache;
  71
  72         struct ip_tunnel_parm parms;
  73
  74         int             encap_hlen;     /* Encap header length (FOU,GUE) */
  75         struct ip_tunnel_encap encap;
  76
  77         int             hlen;           /* tun_hlen + encap_hlen */
  78
  79         /* for SIT */
  80 #ifdef CONFIG_IPV6_SIT_6RD
  81         struct ip_tunnel_6rd_parm ip6rd;
  82 #endif
  83         struct ip_tunnel_prl_entry __rcu *prl;  /* potential router list */
  84         unsigned int            prl_count;      /* # of entries in PRL */
  85         int                     ip_tnl_net_id;
  86         struct gro_cells        gro_cells;
  87 };
  88
  89 #define TUNNEL_CSUM             __cpu_to_be16(0x01)
  90 #define TUNNEL_ROUTING          __cpu_to_be16(0x02)
  91 #define TUNNEL_KEY              __cpu_to_be16(0x04)
  92 #define TUNNEL_SEQ              __cpu_to_be16(0x08)
  93 #define TUNNEL_STRICT           __cpu_to_be16(0x10)
  94 #define TUNNEL_REC              __cpu_to_be16(0x20)
  95 #define TUNNEL_VERSION          __cpu_to_be16(0x40)
  96 #define TUNNEL_NO_KEY           __cpu_to_be16(0x80)
  97 #define TUNNEL_DONT_FRAGMENT    __cpu_to_be16(0x0100)
  98 #define TUNNEL_OAM              __cpu_to_be16(0x0200)
  99 #define TUNNEL_CRIT_OPT         __cpu_to_be16(0x0400)
 100 #define TUNNEL_OPTIONS_PRESENT  __cpu_to_be16(0x0800)
 101
 102 struct tnl_ptk_info {
 103         __be16 flags;
 104         __be16 proto;
 105         __be32 key;
 106         __be32 seq;
 107 };
 108
 109 #define PACKET_RCVD     0
 110 #define PACKET_REJECT   1
 111
 112 #define IP_TNL_HASH_BITS   7
 113 #define IP_TNL_HASH_SIZE   (1 << IP_TNL_HASH_BITS)
 114
 115 struct ip_tunnel_net {
 116         struct net_device *fb_tunnel_dev;
 117         struct hlist_head tunnels[IP_TNL_HASH_SIZE];
 118 };
 119
 120 struct ip_tunnel_encap_ops {
 121         size_t (*encap_hlen)(struct ip_tunnel_encap *e);
 122         int (*build_header)(struct sk_buff *skb, struct ip_tunnel_encap *e,
 123                             u8 *protocol, struct flowi4 *fl4);
 124 };
 125
 126 #define MAX_IPTUN_ENCAP_OPS 8
 127
 128 extern const struct ip_tunnel_encap_ops __rcu *
 129                 iptun_encaps[MAX_IPTUN_ENCAP_OPS];
 130
 131 int ip_tunnel_encap_add_ops(const struct ip_tunnel_encap_ops *op,
 132                             unsigned int num);
 133 int ip_tunnel_encap_del_ops(const struct ip_tunnel_encap_ops *op,
 134                             unsigned int num);
 135
 136 #ifdef CONFIG_INET
 137
 138 int ip_tunnel_init(struct net_device *dev);
 139 void ip_tunnel_uninit(struct net_device *dev);
 140 void  ip_tunnel_dellink(struct net_device *dev, struct list_head *head);
 141 int ip_tunnel_init_net(struct net *net, int ip_tnl_net_id,
 142                        struct rtnl_link_ops *ops, char *devname);
 143
 144 void ip_tunnel_delete_net(struct ip_tunnel_net *itn, struct rtnl_link_ops *ops);
 145
 146 void ip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev,
 147                     const struct iphdr *tnl_params, const u8 protocol);
 148 int ip_tunnel_ioctl(struct net_device *dev, struct ip_tunnel_parm *p, int cmd);
 149 int ip_tunnel_encap(struct sk_buff *skb, struct ip_tunnel *t,
 150                     u8 *protocol, struct flowi4 *fl4);
 151 int ip_tunnel_change_mtu(struct net_device *dev, int new_mtu);
 152
 153 struct rtnl_link_stats64 *ip_tunnel_get_stats64(struct net_device *dev,
 154                                                 struct rtnl_link_stats64 *tot);
 155 struct ip_tunnel *ip_tunnel_lookup(struct ip_tunnel_net *itn,
 156                                    int link, __be16 flags,
 157                                    __be32 remote, __be32 local,
 158                                    __be32 key);
 159
 160 int ip_tunnel_rcv(struct ip_tunnel *tunnel, struct sk_buff *skb,
 161                   const struct tnl_ptk_info *tpi, bool log_ecn_error);
 162 int ip_tunnel_changelink(struct net_device *dev, struct nlattr *tb[],
 163                          struct ip_tunnel_parm *p);
 164 int ip_tunnel_newlink(struct net_device *dev, struct nlattr *tb[],
 165                       struct ip_tunnel_parm *p);
 166 void ip_tunnel_setup(struct net_device *dev, int net_id);
 167 void ip_tunnel_dst_reset_all(struct ip_tunnel *t);
 168 int ip_tunnel_encap_setup(struct ip_tunnel *t,
 169                           struct ip_tunnel_encap *ipencap);
 170
 171 /* Extract dsfield from inner protocol */
 172 static inline u8 ip_tunnel_get_dsfield(const struct iphdr *iph,
 173                                        const struct sk_buff *skb)
 174 {
 175         if (skb->protocol == htons(ETH_P_IP))
 176                 return iph->tos;
 177         else if (skb->protocol == htons(ETH_P_IPV6))
 178                 return ipv6_get_dsfield((const struct ipv6hdr *)iph);
 179         else
 180                 return 0;
 181 }
 182
 183 /* Propogate ECN bits out */
 184 static inline u8 ip_tunnel_ecn_encap(u8 tos, const struct iphdr *iph,
 185                                      const struct sk_buff *skb)
 186 {
 187         u8 inner = ip_tunnel_get_dsfield(iph, skb);
 188
 189         return INET_ECN_encapsulate(tos, inner);
 190 }
 191
 192 int iptunnel_pull_header(struct sk_buff *skb, int hdr_len, __be16 inner_proto);
 193 int iptunnel_xmit(struct sock *sk, struct rtable *rt, struct sk_buff *skb,
 194                   __be32 src, __be32 dst, __u8 proto,
 195                   __u8 tos, __u8 ttl, __be16 df, bool xnet);
 196
 197 struct sk_buff *iptunnel_handle_offloads(struct sk_buff *skb, bool gre_csum,
 198                                          int gso_type_mask);
 199
 200 static inline void iptunnel_xmit_stats(int err,
 201                                        struct net_device_stats *err_stats,
 202                                        struct pcpu_sw_netstats __percpu *stats)
 203 {
 204         if (err > 0) {
 205                 struct pcpu_sw_netstats *tstats = this_cpu_ptr(stats);
 206
 207                 u64_stats_update_begin(&tstats->syncp);
 208                 tstats->tx_bytes += err;
 209                 tstats->tx_packets++;
 210                 u64_stats_update_end(&tstats->syncp);
 211         } else if (err < 0) {
 212                 err_stats->tx_errors++;
 213                 err_stats->tx_aborted_errors++;
 214         } else {
 215                 err_stats->tx_dropped++;
 216         }
 217 }
 218
 219 #endif /* CONFIG_INET */
 220
 221 #endif /* __NET_IP_TUNNELS_H */