xref: /openbmc/linux/include/net/ip6_route.h (revision 4f205687)
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_flags(struct net *net, const struct sock *sk,
68 					 struct flowi6 *fl6, int flags);
69 
70 static inline struct dst_entry *ip6_route_output(struct net *net,
71 						 const struct sock *sk,
72 						 struct flowi6 *fl6)
73 {
74 	return ip6_route_output_flags(net, sk, fl6, 0);
75 }
76 
77 struct dst_entry *ip6_route_lookup(struct net *net, struct flowi6 *fl6,
78 				   int flags);
79 
80 int ip6_route_init(void);
81 void ip6_route_cleanup(void);
82 
83 int ipv6_route_ioctl(struct net *net, unsigned int cmd, void __user *arg);
84 
85 int ip6_route_add(struct fib6_config *cfg);
86 int ip6_ins_rt(struct rt6_info *);
87 int ip6_del_rt(struct rt6_info *);
88 
89 int ip6_route_get_saddr(struct net *net, struct rt6_info *rt,
90 			const struct in6_addr *daddr, unsigned int prefs,
91 			struct in6_addr *saddr);
92 
93 struct rt6_info *rt6_lookup(struct net *net, const struct in6_addr *daddr,
94 			    const struct in6_addr *saddr, int oif, int flags);
95 
96 struct dst_entry *icmp6_dst_alloc(struct net_device *dev, struct flowi6 *fl6);
97 int icmp6_dst_gc(void);
98 
99 void fib6_force_start_gc(struct net *net);
100 
101 struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev,
102 				    const struct in6_addr *addr, bool anycast);
103 
104 struct rt6_info *ip6_dst_alloc(struct net *net, struct net_device *dev,
105 			       int flags);
106 
107 /*
108  *	support functions for ND
109  *
110  */
111 struct rt6_info *rt6_get_dflt_router(const struct in6_addr *addr,
112 				     struct net_device *dev);
113 struct rt6_info *rt6_add_dflt_router(const struct in6_addr *gwaddr,
114 				     struct net_device *dev, unsigned int pref);
115 
116 void rt6_purge_dflt_routers(struct net *net);
117 
118 int rt6_route_rcv(struct net_device *dev, u8 *opt, int len,
119 		  const struct in6_addr *gwaddr);
120 
121 void ip6_update_pmtu(struct sk_buff *skb, struct net *net, __be32 mtu, int oif,
122 		     u32 mark);
123 void ip6_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, __be32 mtu);
124 void ip6_redirect(struct sk_buff *skb, struct net *net, int oif, u32 mark);
125 void ip6_redirect_no_header(struct sk_buff *skb, struct net *net, int oif,
126 			    u32 mark);
127 void ip6_sk_redirect(struct sk_buff *skb, struct sock *sk);
128 
129 struct netlink_callback;
130 
131 struct rt6_rtnl_dump_arg {
132 	struct sk_buff *skb;
133 	struct netlink_callback *cb;
134 	struct net *net;
135 };
136 
137 int rt6_dump_route(struct rt6_info *rt, void *p_arg);
138 void rt6_ifdown(struct net *net, struct net_device *dev);
139 void rt6_mtu_change(struct net_device *dev, unsigned int mtu);
140 void rt6_remove_prefsrc(struct inet6_ifaddr *ifp);
141 void rt6_clean_tohost(struct net *net, struct in6_addr *gateway);
142 
143 
144 /*
145  *	Store a destination cache entry in a socket
146  */
147 static inline void ip6_dst_store(struct sock *sk, struct dst_entry *dst,
148 				 const struct in6_addr *daddr,
149 				 const struct in6_addr *saddr)
150 {
151 	struct ipv6_pinfo *np = inet6_sk(sk);
152 
153 	np->dst_cookie = rt6_get_cookie((struct rt6_info *)dst);
154 	sk_setup_caps(sk, dst);
155 	np->daddr_cache = daddr;
156 #ifdef CONFIG_IPV6_SUBTREES
157 	np->saddr_cache = saddr;
158 #endif
159 }
160 
161 static inline bool ipv6_unicast_destination(const struct sk_buff *skb)
162 {
163 	struct rt6_info *rt = (struct rt6_info *) skb_dst(skb);
164 
165 	return rt->rt6i_flags & RTF_LOCAL;
166 }
167 
168 static inline bool ipv6_anycast_destination(const struct dst_entry *dst,
169 					    const struct in6_addr *daddr)
170 {
171 	struct rt6_info *rt = (struct rt6_info *)dst;
172 
173 	return rt->rt6i_flags & RTF_ANYCAST ||
174 		(rt->rt6i_dst.plen != 128 &&
175 		 ipv6_addr_equal(&rt->rt6i_dst.addr, daddr));
176 }
177 
178 int ip6_fragment(struct net *net, struct sock *sk, struct sk_buff *skb,
179 		 int (*output)(struct net *, struct sock *, struct sk_buff *));
180 
181 static inline int ip6_skb_dst_mtu(struct sk_buff *skb)
182 {
183 	struct ipv6_pinfo *np = skb->sk && !dev_recursion_level() ?
184 				inet6_sk(skb->sk) : NULL;
185 
186 	return (np && np->pmtudisc >= IPV6_PMTUDISC_PROBE) ?
187 	       skb_dst(skb)->dev->mtu : dst_mtu(skb_dst(skb));
188 }
189 
190 static inline bool ip6_sk_accept_pmtu(const struct sock *sk)
191 {
192 	return inet6_sk(sk)->pmtudisc != IPV6_PMTUDISC_INTERFACE &&
193 	       inet6_sk(sk)->pmtudisc != IPV6_PMTUDISC_OMIT;
194 }
195 
196 static inline bool ip6_sk_ignore_df(const struct sock *sk)
197 {
198 	return inet6_sk(sk)->pmtudisc < IPV6_PMTUDISC_DO ||
199 	       inet6_sk(sk)->pmtudisc == IPV6_PMTUDISC_OMIT;
200 }
201 
202 static inline struct in6_addr *rt6_nexthop(struct rt6_info *rt,
203 					   struct in6_addr *daddr)
204 {
205 	if (rt->rt6i_flags & RTF_GATEWAY)
206 		return &rt->rt6i_gateway;
207 	else if (unlikely(rt->rt6i_flags & RTF_CACHE))
208 		return &rt->rt6i_dst.addr;
209 	else
210 		return daddr;
211 }
212 
213 #endif
214