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 };
  40
  41 /* IPv6 tunnel */
  42 struct ip6_tnl {
  43         struct ip6_tnl __rcu *next;     /* next tunnel in list */
  44         struct net_device *dev; /* virtual device associated with tunnel */
  45         struct net *net;        /* netns for packet i/o */
  46         struct __ip6_tnl_parm parms;    /* tunnel configuration parameters */
  47         struct flowi fl;        /* flowi template for xmit */
  48         struct dst_cache dst_cache;     /* cached dst */
  49         struct gro_cells gro_cells;
  50
  51         int err_count;
  52         unsigned long err_time;
  53
  54         /* These fields used only by GRE */
  55         __u32 i_seqno;  /* The last seen seqno  */
  56         __u32 o_seqno;  /* The last output seqno */
  57         int hlen;       /* tun_hlen + encap_hlen */
  58         int tun_hlen;   /* Precalculated header length */
  59         int encap_hlen; /* Encap header length (FOU,GUE) */
  60         struct ip_tunnel_encap encap;
  61         int mlink;
  62 };
  63
  64 struct ip6_tnl_encap_ops {
  65         size_t (*encap_hlen)(struct ip_tunnel_encap *e);
  66         int (*build_header)(struct sk_buff *skb, struct ip_tunnel_encap *e,
  67                             u8 *protocol, struct flowi6 *fl6);
  68 };
  69
  70 #ifdef CONFIG_INET
  71
  72 extern const struct ip6_tnl_encap_ops __rcu *
  73                 ip6tun_encaps[MAX_IPTUN_ENCAP_OPS];
  74
  75 int ip6_tnl_encap_add_ops(const struct ip6_tnl_encap_ops *ops,
  76                           unsigned int num);
  77 int ip6_tnl_encap_del_ops(const struct ip6_tnl_encap_ops *ops,
  78                           unsigned int num);
  79 int ip6_tnl_encap_setup(struct ip6_tnl *t,
  80                         struct ip_tunnel_encap *ipencap);
  81
  82 static inline int ip6_encap_hlen(struct ip_tunnel_encap *e)
  83 {
  84         const struct ip6_tnl_encap_ops *ops;
  85         int hlen = -EINVAL;
  86
  87         if (e->type == TUNNEL_ENCAP_NONE)
  88                 return 0;
  89
  90         if (e->type >= MAX_IPTUN_ENCAP_OPS)
  91                 return -EINVAL;
  92
  93         rcu_read_lock();
  94         ops = rcu_dereference(ip6tun_encaps[e->type]);
  95         if (likely(ops && ops->encap_hlen))
  96                 hlen = ops->encap_hlen(e);
  97         rcu_read_unlock();
  98
  99         return hlen;
 100 }
 101
 102 static inline int ip6_tnl_encap(struct sk_buff *skb, struct ip6_tnl *t,
 103                                 u8 *protocol, struct flowi6 *fl6)
 104 {
 105         const struct ip6_tnl_encap_ops *ops;
 106         int ret = -EINVAL;
 107
 108         if (t->encap.type == TUNNEL_ENCAP_NONE)
 109                 return 0;
 110
 111         if (t->encap.type >= MAX_IPTUN_ENCAP_OPS)
 112                 return -EINVAL;
 113
 114         rcu_read_lock();
 115         ops = rcu_dereference(ip6tun_encaps[t->encap.type]);
 116         if (likely(ops && ops->build_header))
 117                 ret = ops->build_header(skb, &t->encap, protocol, fl6);
 118         rcu_read_unlock();
 119
 120         return ret;
 121 }
 122
 123 /* Tunnel encapsulation limit destination sub-option */
 124
 125 struct ipv6_tlv_tnl_enc_lim {
 126         __u8 type;              /* type-code for option         */
 127         __u8 length;            /* option length                */
 128         __u8 encap_limit;       /* tunnel encapsulation limit   */
 129 } __packed;
 130
 131 int ip6_tnl_rcv_ctl(struct ip6_tnl *t, const struct in6_addr *laddr,
 132                 const struct in6_addr *raddr);
 133 int ip6_tnl_rcv(struct ip6_tnl *tunnel, struct sk_buff *skb,
 134                 const struct tnl_ptk_info *tpi, struct metadata_dst *tun_dst,
 135                 bool log_ecn_error);
 136 int ip6_tnl_xmit_ctl(struct ip6_tnl *t, const struct in6_addr *laddr,
 137                      const struct in6_addr *raddr);
 138 int ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev, __u8 dsfield,
 139                  struct flowi6 *fl6, int encap_limit, __u32 *pmtu, __u8 proto);
 140 __u16 ip6_tnl_parse_tlv_enc_lim(struct sk_buff *skb, __u8 *raw);
 141 __u32 ip6_tnl_get_cap(struct ip6_tnl *t, const struct in6_addr *laddr,
 142                              const struct in6_addr *raddr);
 143 struct net *ip6_tnl_get_link_net(const struct net_device *dev);
 144 int ip6_tnl_get_iflink(const struct net_device *dev);
 145 int ip6_tnl_change_mtu(struct net_device *dev, int new_mtu);
 146
 147 static inline void ip6tunnel_xmit(struct sock *sk, struct sk_buff *skb,
 148                                   struct net_device *dev)
 149 {
 150         int pkt_len, err;
 151
 152         memset(skb->cb, 0, sizeof(struct inet6_skb_parm));
 153         pkt_len = skb->len - skb_inner_network_offset(skb);
 154         err = ip6_local_out(dev_net(skb_dst(skb)->dev), sk, skb);
 155
 156         if (dev) {
 157                 if (unlikely(net_xmit_eval(err)))
 158                         pkt_len = -1;
 159                 iptunnel_xmit_stats(dev, pkt_len);
 160         }
 161 }
 162 #endif
 163 #endif