include/net/ip6_tunnel.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _NET_IP6_TUNNEL_H
   3 #define _NET_IP6_TUNNEL_H
   4
   5 #include <linux/ipv6.h>
   6 #include <linux/netdevice.h>
   7 #include <linux/if_tunnel.h>
   8 #include <linux/ip6_tunnel.h>
   9 #include <net/ip_tunnels.h>
  10 #include <net/dst_cache.h>
  11
  12 #define IP6TUNNEL_ERR_TIMEO (30*HZ)
  13
  14 /* capable of sending packets */
  15 #define IP6_TNL_F_CAP_XMIT 0x10000
  16 /* capable of receiving packets */
  17 #define IP6_TNL_F_CAP_RCV 0x20000
  18 /* determine capability on a per-packet basis */
  19 #define IP6_TNL_F_CAP_PER_PACKET 0x40000
  20
  21 struct __ip6_tnl_parm {
  22         char name[IFNAMSIZ];    /* name of tunnel device */
  23         int link;               /* ifindex of underlying L2 interface */
  24         __u8 proto;             /* tunnel protocol */
  25         __u8 encap_limit;       /* encapsulation limit for tunnel */
  26         __u8 hop_limit;         /* hop limit for tunnel */
  27         bool collect_md;
  28         __be32 flowinfo;        /* traffic class and flowlabel for tunnel */
  29         __u32 flags;            /* tunnel flags */
  30         struct in6_addr laddr;  /* local tunnel end-point address */
  31         struct in6_addr raddr;  /* remote tunnel end-point address */
  32
  33         __be16                  i_flags;
  34         __be16                  o_flags;
  35         __be32                  i_key;
  36         __be32                  o_key;
  37
  38         __u32                   fwmark;
  39         __u32                   index;  /* ERSPAN type II index */
  40         __u8                    erspan_ver;     /* ERSPAN version */
  41         __u8                    dir;    /* direction */
  42         __u16                   hwid;   /* hwid */
  43 };
  44
  45 /* IPv6 tunnel */
  46 struct ip6_tnl {
  47         struct ip6_tnl __rcu *next;     /* next tunnel in list */
  48         struct net_device *dev; /* virtual device associated with tunnel */
  49         struct net *net;        /* netns for packet i/o */
  50         struct __ip6_tnl_parm parms;    /* tunnel configuration parameters */
  51         struct flowi fl;        /* flowi template for xmit */
  52         struct dst_cache dst_cache;     /* cached dst */
  53         struct gro_cells gro_cells;
  54
  55         int err_count;
  56         unsigned long err_time;
  57
  58         /* These fields used only by GRE */
  59         __u32 i_seqno;  /* The last seen seqno  */
  60         __u32 o_seqno;  /* The last output seqno */
  61         int hlen;       /* tun_hlen + encap_hlen */
  62         int tun_hlen;   /* Precalculated header length */
  63         int encap_hlen; /* Encap header length (FOU,GUE) */
  64         struct ip_tunnel_encap encap;
  65         int mlink;
  66 };
  67
  68 struct ip6_tnl_encap_ops {
  69         size_t (*encap_hlen)(struct ip_tunnel_encap *e);
  70         int (*build_header)(struct sk_buff *skb, struct ip_tunnel_encap *e,
  71                             u8 *protocol, struct flowi6 *fl6);
  72 };
  73
  74 #ifdef CONFIG_INET
  75
  76 extern const struct ip6_tnl_encap_ops __rcu *
  77                 ip6tun_encaps[MAX_IPTUN_ENCAP_OPS];
  78
  79 int ip6_tnl_encap_add_ops(const struct ip6_tnl_encap_ops *ops,
  80                           unsigned int num);
  81 int ip6_tnl_encap_del_ops(const struct ip6_tnl_encap_ops *ops,
  82                           unsigned int num);
  83 int ip6_tnl_encap_setup(struct ip6_tnl *t,
  84                         struct ip_tunnel_encap *ipencap);
  85
  86 static inline int ip6_encap_hlen(struct ip_tunnel_encap *e)
  87 {
  88         const struct ip6_tnl_encap_ops *ops;
  89         int hlen = -EINVAL;
  90
  91         if (e->type == TUNNEL_ENCAP_NONE)
  92                 return 0;
  93
  94         if (e->type >= MAX_IPTUN_ENCAP_OPS)
  95                 return -EINVAL;
  96
  97         rcu_read_lock();
  98         ops = rcu_dereference(ip6tun_encaps[e->type]);
  99         if (likely(ops && ops->encap_hlen))
 100                 hlen = ops->encap_hlen(e);
 101         rcu_read_unlock();
 102
 103         return hlen;
 104 }
 105
 106 static inline int ip6_tnl_encap(struct sk_buff *skb, struct ip6_tnl *t,
 107                                 u8 *protocol, struct flowi6 *fl6)
 108 {
 109         const struct ip6_tnl_encap_ops *ops;
 110         int ret = -EINVAL;
 111
 112         if (t->encap.type == TUNNEL_ENCAP_NONE)
 113                 return 0;
 114
 115         if (t->encap.type >= MAX_IPTUN_ENCAP_OPS)
 116                 return -EINVAL;
 117
 118         rcu_read_lock();
 119         ops = rcu_dereference(ip6tun_encaps[t->encap.type]);
 120         if (likely(ops && ops->build_header))
 121                 ret = ops->build_header(skb, &t->encap, protocol, fl6);
 122         rcu_read_unlock();
 123
 124         return ret;
 125 }
 126
 127 /* Tunnel encapsulation limit destination sub-option */
 128
 129 struct ipv6_tlv_tnl_enc_lim {
 130         __u8 type;              /* type-code for option         */
 131         __u8 length;            /* option length                */
 132         __u8 encap_limit;       /* tunnel encapsulation limit   */
 133 } __packed;
 134
 135 int ip6_tnl_rcv_ctl(struct ip6_tnl *t, const struct in6_addr *laddr,
 136                 const struct in6_addr *raddr);
 137 int ip6_tnl_rcv(struct ip6_tnl *tunnel, struct sk_buff *skb,
 138                 const struct tnl_ptk_info *tpi, struct metadata_dst *tun_dst,
 139                 bool log_ecn_error);
 140 int ip6_tnl_xmit_ctl(struct ip6_tnl *t, const struct in6_addr *laddr,
 141                      const struct in6_addr *raddr);
 142 int ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev, __u8 dsfield,
 143                  struct flowi6 *fl6, int encap_limit, __u32 *pmtu, __u8 proto);
 144 __u16 ip6_tnl_parse_tlv_enc_lim(struct sk_buff *skb, __u8 *raw);
 145 __u32 ip6_tnl_get_cap(struct ip6_tnl *t, const struct in6_addr *laddr,
 146                              const struct in6_addr *raddr);
 147 struct net *ip6_tnl_get_link_net(const struct net_device *dev);
 148 int ip6_tnl_get_iflink(const struct net_device *dev);
 149 int ip6_tnl_change_mtu(struct net_device *dev, int new_mtu);
 150
 151 static inline void ip6tunnel_xmit(struct sock *sk, struct sk_buff *skb,
 152                                   struct net_device *dev)
 153 {
 154         int pkt_len, err;
 155
 156         memset(skb->cb, 0, sizeof(struct inet6_skb_parm));
 157         pkt_len = skb->len - skb_inner_network_offset(skb);
 158         err = ip6_local_out(dev_net(skb_dst(skb)->dev), sk, skb);
 159         if (unlikely(net_xmit_eval(err)))
 160                 pkt_len = -1;
 161         iptunnel_xmit_stats(dev, pkt_len);
 162 }
 163 #endif
 164 #endif