xref: /openbmc/linux/include/net/ip_tunnels.h (revision afc98d90)
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_dst {
42 	struct dst_entry __rcu 		*dst;
43 };
44 
45 struct ip_tunnel {
46 	struct ip_tunnel __rcu	*next;
47 	struct hlist_node hash_node;
48 	struct net_device	*dev;
49 	struct net		*net;	/* netns for packet i/o */
50 
51 	int		err_count;	/* Number of arrived ICMP errors */
52 	unsigned long	err_time;	/* Time when the last ICMP error
53 					 * arrived */
54 
55 	/* These four fields used only by GRE */
56 	__u32		i_seqno;	/* The last seen seqno	*/
57 	__u32		o_seqno;	/* The last output seqno */
58 	int		hlen;		/* Precalculated header length */
59 	int		mlink;
60 
61 	struct ip_tunnel_dst __percpu *dst_cache;
62 
63 	struct ip_tunnel_parm parms;
64 
65 	/* for SIT */
66 #ifdef CONFIG_IPV6_SIT_6RD
67 	struct ip_tunnel_6rd_parm ip6rd;
68 #endif
69 	struct ip_tunnel_prl_entry __rcu *prl;	/* potential router list */
70 	unsigned int		prl_count;	/* # of entries in PRL */
71 	int			ip_tnl_net_id;
72 	struct gro_cells	gro_cells;
73 };
74 
75 #define TUNNEL_CSUM	__cpu_to_be16(0x01)
76 #define TUNNEL_ROUTING	__cpu_to_be16(0x02)
77 #define TUNNEL_KEY	__cpu_to_be16(0x04)
78 #define TUNNEL_SEQ	__cpu_to_be16(0x08)
79 #define TUNNEL_STRICT	__cpu_to_be16(0x10)
80 #define TUNNEL_REC	__cpu_to_be16(0x20)
81 #define TUNNEL_VERSION	__cpu_to_be16(0x40)
82 #define TUNNEL_NO_KEY	__cpu_to_be16(0x80)
83 #define TUNNEL_DONT_FRAGMENT    __cpu_to_be16(0x0100)
84 
85 struct tnl_ptk_info {
86 	__be16 flags;
87 	__be16 proto;
88 	__be32 key;
89 	__be32 seq;
90 };
91 
92 #define PACKET_RCVD	0
93 #define PACKET_REJECT	1
94 
95 #define IP_TNL_HASH_BITS   7
96 #define IP_TNL_HASH_SIZE   (1 << IP_TNL_HASH_BITS)
97 
98 struct ip_tunnel_net {
99 	struct net_device *fb_tunnel_dev;
100 	struct hlist_head tunnels[IP_TNL_HASH_SIZE];
101 };
102 
103 #ifdef CONFIG_INET
104 
105 int ip_tunnel_init(struct net_device *dev);
106 void ip_tunnel_uninit(struct net_device *dev);
107 void  ip_tunnel_dellink(struct net_device *dev, struct list_head *head);
108 int ip_tunnel_init_net(struct net *net, int ip_tnl_net_id,
109 		       struct rtnl_link_ops *ops, char *devname);
110 
111 void ip_tunnel_delete_net(struct ip_tunnel_net *itn, struct rtnl_link_ops *ops);
112 
113 void ip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev,
114 		    const struct iphdr *tnl_params, const u8 protocol);
115 int ip_tunnel_ioctl(struct net_device *dev, struct ip_tunnel_parm *p, int cmd);
116 int ip_tunnel_change_mtu(struct net_device *dev, int new_mtu);
117 
118 struct rtnl_link_stats64 *ip_tunnel_get_stats64(struct net_device *dev,
119 						struct rtnl_link_stats64 *tot);
120 struct ip_tunnel *ip_tunnel_lookup(struct ip_tunnel_net *itn,
121 				   int link, __be16 flags,
122 				   __be32 remote, __be32 local,
123 				   __be32 key);
124 
125 int ip_tunnel_rcv(struct ip_tunnel *tunnel, struct sk_buff *skb,
126 		  const struct tnl_ptk_info *tpi, bool log_ecn_error);
127 int ip_tunnel_changelink(struct net_device *dev, struct nlattr *tb[],
128 			 struct ip_tunnel_parm *p);
129 int ip_tunnel_newlink(struct net_device *dev, struct nlattr *tb[],
130 		      struct ip_tunnel_parm *p);
131 void ip_tunnel_setup(struct net_device *dev, int net_id);
132 
133 /* Extract dsfield from inner protocol */
134 static inline u8 ip_tunnel_get_dsfield(const struct iphdr *iph,
135 				       const struct sk_buff *skb)
136 {
137 	if (skb->protocol == htons(ETH_P_IP))
138 		return iph->tos;
139 	else if (skb->protocol == htons(ETH_P_IPV6))
140 		return ipv6_get_dsfield((const struct ipv6hdr *)iph);
141 	else
142 		return 0;
143 }
144 
145 /* Propogate ECN bits out */
146 static inline u8 ip_tunnel_ecn_encap(u8 tos, const struct iphdr *iph,
147 				     const struct sk_buff *skb)
148 {
149 	u8 inner = ip_tunnel_get_dsfield(iph, skb);
150 
151 	return INET_ECN_encapsulate(tos, inner);
152 }
153 
154 int iptunnel_pull_header(struct sk_buff *skb, int hdr_len, __be16 inner_proto);
155 int iptunnel_xmit(struct rtable *rt, struct sk_buff *skb,
156 		  __be32 src, __be32 dst, __u8 proto,
157 		  __u8 tos, __u8 ttl, __be16 df, bool xnet);
158 
159 struct sk_buff *iptunnel_handle_offloads(struct sk_buff *skb, bool gre_csum,
160 					 int gso_type_mask);
161 
162 static inline void iptunnel_xmit_stats(int err,
163 				       struct net_device_stats *err_stats,
164 				       struct pcpu_sw_netstats __percpu *stats)
165 {
166 	if (err > 0) {
167 		struct pcpu_sw_netstats *tstats = this_cpu_ptr(stats);
168 
169 		u64_stats_update_begin(&tstats->syncp);
170 		tstats->tx_bytes += err;
171 		tstats->tx_packets++;
172 		u64_stats_update_end(&tstats->syncp);
173 	} else if (err < 0) {
174 		err_stats->tx_errors++;
175 		err_stats->tx_aborted_errors++;
176 	} else {
177 		err_stats->tx_dropped++;
178 	}
179 }
180 
181 #endif /* CONFIG_INET */
182 
183 #endif /* __NET_IP_TUNNELS_H */
184