xref: /openbmc/linux/include/net/ip_tunnels.h (revision e23feb16)
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 	struct net		*net;	/* netns for packet i/o */
46 
47 	int		err_count;	/* Number of arrived ICMP errors */
48 	unsigned long	err_time;	/* Time when the last ICMP error
49 					 * arrived */
50 
51 	/* These four fields used only by GRE */
52 	__u32		i_seqno;	/* The last seen seqno	*/
53 	__u32		o_seqno;	/* The last output seqno */
54 	int		hlen;		/* Precalculated header length */
55 	int		mlink;
56 
57 	struct ip_tunnel_parm parms;
58 
59 	/* for SIT */
60 #ifdef CONFIG_IPV6_SIT_6RD
61 	struct ip_tunnel_6rd_parm ip6rd;
62 #endif
63 	struct ip_tunnel_prl_entry __rcu *prl;	/* potential router list */
64 	unsigned int		prl_count;	/* # of entries in PRL */
65 	int			ip_tnl_net_id;
66 	struct gro_cells	gro_cells;
67 };
68 
69 #define TUNNEL_CSUM	__cpu_to_be16(0x01)
70 #define TUNNEL_ROUTING	__cpu_to_be16(0x02)
71 #define TUNNEL_KEY	__cpu_to_be16(0x04)
72 #define TUNNEL_SEQ	__cpu_to_be16(0x08)
73 #define TUNNEL_STRICT	__cpu_to_be16(0x10)
74 #define TUNNEL_REC	__cpu_to_be16(0x20)
75 #define TUNNEL_VERSION	__cpu_to_be16(0x40)
76 #define TUNNEL_NO_KEY	__cpu_to_be16(0x80)
77 #define TUNNEL_DONT_FRAGMENT    __cpu_to_be16(0x0100)
78 
79 struct tnl_ptk_info {
80 	__be16 flags;
81 	__be16 proto;
82 	__be32 key;
83 	__be32 seq;
84 };
85 
86 #define PACKET_RCVD	0
87 #define PACKET_REJECT	1
88 
89 #define IP_TNL_HASH_BITS   7
90 #define IP_TNL_HASH_SIZE   (1 << IP_TNL_HASH_BITS)
91 
92 struct ip_tunnel_net {
93 	struct net_device *fb_tunnel_dev;
94 	struct hlist_head tunnels[IP_TNL_HASH_SIZE];
95 };
96 
97 #ifdef CONFIG_INET
98 
99 int ip_tunnel_init(struct net_device *dev);
100 void ip_tunnel_uninit(struct net_device *dev);
101 void  ip_tunnel_dellink(struct net_device *dev, struct list_head *head);
102 int ip_tunnel_init_net(struct net *net, int ip_tnl_net_id,
103 		       struct rtnl_link_ops *ops, char *devname);
104 
105 void ip_tunnel_delete_net(struct ip_tunnel_net *itn, struct rtnl_link_ops *ops);
106 
107 void ip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev,
108 		    const struct iphdr *tnl_params, const u8 protocol);
109 int ip_tunnel_ioctl(struct net_device *dev, struct ip_tunnel_parm *p, int cmd);
110 int ip_tunnel_change_mtu(struct net_device *dev, int new_mtu);
111 
112 struct rtnl_link_stats64 *ip_tunnel_get_stats64(struct net_device *dev,
113 						struct rtnl_link_stats64 *tot);
114 struct ip_tunnel *ip_tunnel_lookup(struct ip_tunnel_net *itn,
115 				   int link, __be16 flags,
116 				   __be32 remote, __be32 local,
117 				   __be32 key);
118 
119 int ip_tunnel_rcv(struct ip_tunnel *tunnel, struct sk_buff *skb,
120 		  const struct tnl_ptk_info *tpi, bool log_ecn_error);
121 int ip_tunnel_changelink(struct net_device *dev, struct nlattr *tb[],
122 			 struct ip_tunnel_parm *p);
123 int ip_tunnel_newlink(struct net_device *dev, struct nlattr *tb[],
124 		      struct ip_tunnel_parm *p);
125 void ip_tunnel_setup(struct net_device *dev, int net_id);
126 
127 /* Extract dsfield from inner protocol */
128 static inline u8 ip_tunnel_get_dsfield(const struct iphdr *iph,
129 				       const struct sk_buff *skb)
130 {
131 	if (skb->protocol == htons(ETH_P_IP))
132 		return iph->tos;
133 	else if (skb->protocol == htons(ETH_P_IPV6))
134 		return ipv6_get_dsfield((const struct ipv6hdr *)iph);
135 	else
136 		return 0;
137 }
138 
139 /* Propogate ECN bits out */
140 static inline u8 ip_tunnel_ecn_encap(u8 tos, const struct iphdr *iph,
141 				     const struct sk_buff *skb)
142 {
143 	u8 inner = ip_tunnel_get_dsfield(iph, skb);
144 
145 	return INET_ECN_encapsulate(tos, inner);
146 }
147 
148 int iptunnel_pull_header(struct sk_buff *skb, int hdr_len, __be16 inner_proto);
149 int iptunnel_xmit(struct rtable *rt, struct sk_buff *skb,
150 		  __be32 src, __be32 dst, __u8 proto,
151 		  __u8 tos, __u8 ttl, __be16 df, bool xnet);
152 
153 static inline void iptunnel_xmit_stats(int err,
154 				       struct net_device_stats *err_stats,
155 				       struct pcpu_tstats __percpu *stats)
156 {
157 	if (err > 0) {
158 		struct pcpu_tstats *tstats = this_cpu_ptr(stats);
159 
160 		u64_stats_update_begin(&tstats->syncp);
161 		tstats->tx_bytes += err;
162 		tstats->tx_packets++;
163 		u64_stats_update_end(&tstats->syncp);
164 	} else if (err < 0) {
165 		err_stats->tx_errors++;
166 		err_stats->tx_aborted_errors++;
167 	} else {
168 		err_stats->tx_dropped++;
169 	}
170 }
171 
172 #endif /* CONFIG_INET */
173 
174 #endif /* __NET_IP_TUNNELS_H */
175