xref: /linux/include/net/ip6_route.h (revision 93d90ad708b8da6efc0e487b66111aa9db7f70c7)
1 #ifndef _NET_IP6_ROUTE_H
2 #define _NET_IP6_ROUTE_H
3 
4 struct route_info {
5 	__u8			type;
6 	__u8			length;
7 	__u8			prefix_len;
8 #if defined(__BIG_ENDIAN_BITFIELD)
9 	__u8			reserved_h:3,
10 				route_pref:2,
11 				reserved_l:3;
12 #elif defined(__LITTLE_ENDIAN_BITFIELD)
13 	__u8			reserved_l:3,
14 				route_pref:2,
15 				reserved_h:3;
16 #endif
17 	__be32			lifetime;
18 	__u8			prefix[0];	/* 0,8 or 16 */
19 };
20 
21 #include <net/flow.h>
22 #include <net/ip6_fib.h>
23 #include <net/sock.h>
24 #include <linux/ip.h>
25 #include <linux/ipv6.h>
26 #include <linux/route.h>
27 
28 #define RT6_LOOKUP_F_IFACE		0x00000001
29 #define RT6_LOOKUP_F_REACHABLE		0x00000002
30 #define RT6_LOOKUP_F_HAS_SADDR		0x00000004
31 #define RT6_LOOKUP_F_SRCPREF_TMP	0x00000008
32 #define RT6_LOOKUP_F_SRCPREF_PUBLIC	0x00000010
33 #define RT6_LOOKUP_F_SRCPREF_COA	0x00000020
34 
35 /* We do not (yet ?) support IPv6 jumbograms (RFC 2675)
36  * Unlike IPv4, hdr->seg_len doesn't include the IPv6 header
37  */
38 #define IP6_MAX_MTU (0xFFFF + sizeof(struct ipv6hdr))
39 
40 /*
41  * rt6_srcprefs2flags() and rt6_flags2srcprefs() translate
42  * between IPV6_ADDR_PREFERENCES socket option values
43  *	IPV6_PREFER_SRC_TMP    = 0x1
44  *	IPV6_PREFER_SRC_PUBLIC = 0x2
45  *	IPV6_PREFER_SRC_COA    = 0x4
46  * and above RT6_LOOKUP_F_SRCPREF_xxx flags.
47  */
48 static inline int rt6_srcprefs2flags(unsigned int srcprefs)
49 {
50 	/* No need to bitmask because srcprefs have only 3 bits. */
51 	return srcprefs << 3;
52 }
53 
54 static inline unsigned int rt6_flags2srcprefs(int flags)
55 {
56 	return (flags >> 3) & 7;
57 }
58 
59 static inline bool rt6_need_strict(const struct in6_addr *daddr)
60 {
61 	return ipv6_addr_type(daddr) &
62 		(IPV6_ADDR_MULTICAST | IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
63 }
64 
65 void ip6_route_input(struct sk_buff *skb);
66 
67 struct dst_entry *ip6_route_output(struct net *net, const struct sock *sk,
68 				   struct flowi6 *fl6);
69 struct dst_entry *ip6_route_lookup(struct net *net, struct flowi6 *fl6,
70 				   int flags);
71 
72 int ip6_route_init(void);
73 void ip6_route_cleanup(void);
74 
75 int ipv6_route_ioctl(struct net *net, unsigned int cmd, void __user *arg);
76 
77 int ip6_route_add(struct fib6_config *cfg);
78 int ip6_ins_rt(struct rt6_info *);
79 int ip6_del_rt(struct rt6_info *);
80 
81 int ip6_route_get_saddr(struct net *net, struct rt6_info *rt,
82 			const struct in6_addr *daddr, unsigned int prefs,
83 			struct in6_addr *saddr);
84 
85 struct rt6_info *rt6_lookup(struct net *net, const struct in6_addr *daddr,
86 			    const struct in6_addr *saddr, int oif, int flags);
87 
88 struct dst_entry *icmp6_dst_alloc(struct net_device *dev, struct flowi6 *fl6);
89 int icmp6_dst_gc(void);
90 
91 void fib6_force_start_gc(struct net *net);
92 
93 struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev,
94 				    const struct in6_addr *addr, bool anycast);
95 
96 /*
97  *	support functions for ND
98  *
99  */
100 struct rt6_info *rt6_get_dflt_router(const struct in6_addr *addr,
101 				     struct net_device *dev);
102 struct rt6_info *rt6_add_dflt_router(const struct in6_addr *gwaddr,
103 				     struct net_device *dev, unsigned int pref);
104 
105 void rt6_purge_dflt_routers(struct net *net);
106 
107 int rt6_route_rcv(struct net_device *dev, u8 *opt, int len,
108 		  const struct in6_addr *gwaddr);
109 
110 void ip6_update_pmtu(struct sk_buff *skb, struct net *net, __be32 mtu, int oif,
111 		     u32 mark);
112 void ip6_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, __be32 mtu);
113 void ip6_redirect(struct sk_buff *skb, struct net *net, int oif, u32 mark);
114 void ip6_redirect_no_header(struct sk_buff *skb, struct net *net, int oif,
115 			    u32 mark);
116 void ip6_sk_redirect(struct sk_buff *skb, struct sock *sk);
117 
118 struct netlink_callback;
119 
120 struct rt6_rtnl_dump_arg {
121 	struct sk_buff *skb;
122 	struct netlink_callback *cb;
123 	struct net *net;
124 };
125 
126 int rt6_dump_route(struct rt6_info *rt, void *p_arg);
127 void rt6_ifdown(struct net *net, struct net_device *dev);
128 void rt6_mtu_change(struct net_device *dev, unsigned int mtu);
129 void rt6_remove_prefsrc(struct inet6_ifaddr *ifp);
130 void rt6_clean_tohost(struct net *net, struct in6_addr *gateway);
131 
132 
133 /*
134  *	Store a destination cache entry in a socket
135  */
136 static inline void __ip6_dst_store(struct sock *sk, struct dst_entry *dst,
137 				   const struct in6_addr *daddr,
138 				   const struct in6_addr *saddr)
139 {
140 	struct ipv6_pinfo *np = inet6_sk(sk);
141 	struct rt6_info *rt = (struct rt6_info *) dst;
142 
143 	sk_setup_caps(sk, dst);
144 	np->daddr_cache = daddr;
145 #ifdef CONFIG_IPV6_SUBTREES
146 	np->saddr_cache = saddr;
147 #endif
148 	np->dst_cookie = rt->rt6i_node ? rt->rt6i_node->fn_sernum : 0;
149 }
150 
151 static inline void ip6_dst_store(struct sock *sk, struct dst_entry *dst,
152 				 struct in6_addr *daddr, struct in6_addr *saddr)
153 {
154 	spin_lock(&sk->sk_dst_lock);
155 	__ip6_dst_store(sk, dst, daddr, saddr);
156 	spin_unlock(&sk->sk_dst_lock);
157 }
158 
159 static inline bool ipv6_unicast_destination(const struct sk_buff *skb)
160 {
161 	struct rt6_info *rt = (struct rt6_info *) skb_dst(skb);
162 
163 	return rt->rt6i_flags & RTF_LOCAL;
164 }
165 
166 static inline bool ipv6_anycast_destination(const struct sk_buff *skb)
167 {
168 	struct rt6_info *rt = (struct rt6_info *) skb_dst(skb);
169 
170 	return rt->rt6i_flags & RTF_ANYCAST;
171 }
172 
173 int ip6_fragment(struct sk_buff *skb, int (*output)(struct sk_buff *));
174 
175 static inline int ip6_skb_dst_mtu(struct sk_buff *skb)
176 {
177 	struct ipv6_pinfo *np = skb->sk ? inet6_sk(skb->sk) : NULL;
178 
179 	return (np && np->pmtudisc >= IPV6_PMTUDISC_PROBE) ?
180 	       skb_dst(skb)->dev->mtu : dst_mtu(skb_dst(skb));
181 }
182 
183 static inline bool ip6_sk_accept_pmtu(const struct sock *sk)
184 {
185 	return inet6_sk(sk)->pmtudisc != IPV6_PMTUDISC_INTERFACE &&
186 	       inet6_sk(sk)->pmtudisc != IPV6_PMTUDISC_OMIT;
187 }
188 
189 static inline bool ip6_sk_ignore_df(const struct sock *sk)
190 {
191 	return inet6_sk(sk)->pmtudisc < IPV6_PMTUDISC_DO ||
192 	       inet6_sk(sk)->pmtudisc == IPV6_PMTUDISC_OMIT;
193 }
194 
195 static inline struct in6_addr *rt6_nexthop(struct rt6_info *rt)
196 {
197 	return &rt->rt6i_gateway;
198 }
199 
200 #endif
201