xref: /openbmc/linux/include/net/ip6_route.h (revision 239480ab)
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/addrconf.h>
22 #include <net/flow.h>
23 #include <net/ip6_fib.h>
24 #include <net/sock.h>
25 #include <linux/ip.h>
26 #include <linux/ipv6.h>
27 #include <linux/route.h>
28 
29 #define RT6_LOOKUP_F_IFACE		0x00000001
30 #define RT6_LOOKUP_F_REACHABLE		0x00000002
31 #define RT6_LOOKUP_F_HAS_SADDR		0x00000004
32 #define RT6_LOOKUP_F_SRCPREF_TMP	0x00000008
33 #define RT6_LOOKUP_F_SRCPREF_PUBLIC	0x00000010
34 #define RT6_LOOKUP_F_SRCPREF_COA	0x00000020
35 #define RT6_LOOKUP_F_IGNORE_LINKSTATE	0x00000040
36 
37 /* We do not (yet ?) support IPv6 jumbograms (RFC 2675)
38  * Unlike IPv4, hdr->seg_len doesn't include the IPv6 header
39  */
40 #define IP6_MAX_MTU (0xFFFF + sizeof(struct ipv6hdr))
41 
42 /*
43  * rt6_srcprefs2flags() and rt6_flags2srcprefs() translate
44  * between IPV6_ADDR_PREFERENCES socket option values
45  *	IPV6_PREFER_SRC_TMP    = 0x1
46  *	IPV6_PREFER_SRC_PUBLIC = 0x2
47  *	IPV6_PREFER_SRC_COA    = 0x4
48  * and above RT6_LOOKUP_F_SRCPREF_xxx flags.
49  */
50 static inline int rt6_srcprefs2flags(unsigned int srcprefs)
51 {
52 	/* No need to bitmask because srcprefs have only 3 bits. */
53 	return srcprefs << 3;
54 }
55 
56 static inline unsigned int rt6_flags2srcprefs(int flags)
57 {
58 	return (flags >> 3) & 7;
59 }
60 
61 static inline bool rt6_need_strict(const struct in6_addr *daddr)
62 {
63 	return ipv6_addr_type(daddr) &
64 		(IPV6_ADDR_MULTICAST | IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
65 }
66 
67 void ip6_route_input(struct sk_buff *skb);
68 struct dst_entry *ip6_route_input_lookup(struct net *net,
69 					 struct net_device *dev,
70 					 struct flowi6 *fl6, int flags);
71 
72 struct dst_entry *ip6_route_output_flags(struct net *net, const struct sock *sk,
73 					 struct flowi6 *fl6, int flags);
74 
75 static inline struct dst_entry *ip6_route_output(struct net *net,
76 						 const struct sock *sk,
77 						 struct flowi6 *fl6)
78 {
79 	return ip6_route_output_flags(net, sk, fl6, 0);
80 }
81 
82 struct dst_entry *ip6_route_lookup(struct net *net, struct flowi6 *fl6,
83 				   int flags);
84 struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table,
85 			       int ifindex, struct flowi6 *fl6, int flags);
86 
87 void ip6_route_init_special_entries(void);
88 int ip6_route_init(void);
89 void ip6_route_cleanup(void);
90 
91 int ipv6_route_ioctl(struct net *net, unsigned int cmd, void __user *arg);
92 
93 int ip6_route_add(struct fib6_config *cfg);
94 int ip6_ins_rt(struct rt6_info *);
95 int ip6_del_rt(struct rt6_info *);
96 
97 static inline int ip6_route_get_saddr(struct net *net, struct rt6_info *rt,
98 				      const struct in6_addr *daddr,
99 				      unsigned int prefs,
100 				      struct in6_addr *saddr)
101 {
102 	struct inet6_dev *idev =
103 			rt ? ip6_dst_idev((struct dst_entry *)rt) : NULL;
104 	int err = 0;
105 
106 	if (rt && rt->rt6i_prefsrc.plen)
107 		*saddr = rt->rt6i_prefsrc.addr;
108 	else
109 		err = ipv6_dev_get_saddr(net, idev ? idev->dev : NULL,
110 					 daddr, prefs, saddr);
111 
112 	return err;
113 }
114 
115 struct rt6_info *rt6_lookup(struct net *net, const struct in6_addr *daddr,
116 			    const struct in6_addr *saddr, int oif, int flags);
117 
118 struct dst_entry *icmp6_dst_alloc(struct net_device *dev, struct flowi6 *fl6);
119 int icmp6_dst_gc(void);
120 
121 void fib6_force_start_gc(struct net *net);
122 
123 struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev,
124 				    const struct in6_addr *addr, bool anycast);
125 
126 struct rt6_info *ip6_dst_alloc(struct net *net, struct net_device *dev,
127 			       int flags);
128 
129 /*
130  *	support functions for ND
131  *
132  */
133 struct rt6_info *rt6_get_dflt_router(const struct in6_addr *addr,
134 				     struct net_device *dev);
135 struct rt6_info *rt6_add_dflt_router(const struct in6_addr *gwaddr,
136 				     struct net_device *dev, unsigned int pref);
137 
138 void rt6_purge_dflt_routers(struct net *net);
139 
140 int rt6_route_rcv(struct net_device *dev, u8 *opt, int len,
141 		  const struct in6_addr *gwaddr);
142 
143 void ip6_update_pmtu(struct sk_buff *skb, struct net *net, __be32 mtu, int oif,
144 		     u32 mark, kuid_t uid);
145 void ip6_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, __be32 mtu);
146 void ip6_redirect(struct sk_buff *skb, struct net *net, int oif, u32 mark,
147 		  kuid_t uid);
148 void ip6_redirect_no_header(struct sk_buff *skb, struct net *net, int oif,
149 			    u32 mark);
150 void ip6_sk_redirect(struct sk_buff *skb, struct sock *sk);
151 
152 struct netlink_callback;
153 
154 struct rt6_rtnl_dump_arg {
155 	struct sk_buff *skb;
156 	struct netlink_callback *cb;
157 	struct net *net;
158 };
159 
160 int rt6_dump_route(struct rt6_info *rt, void *p_arg);
161 void rt6_ifdown(struct net *net, struct net_device *dev);
162 void rt6_mtu_change(struct net_device *dev, unsigned int mtu);
163 void rt6_remove_prefsrc(struct inet6_ifaddr *ifp);
164 void rt6_clean_tohost(struct net *net, struct in6_addr *gateway);
165 
166 
167 /*
168  *	Store a destination cache entry in a socket
169  */
170 static inline void ip6_dst_store(struct sock *sk, struct dst_entry *dst,
171 				 const struct in6_addr *daddr,
172 				 const struct in6_addr *saddr)
173 {
174 	struct ipv6_pinfo *np = inet6_sk(sk);
175 
176 	np->dst_cookie = rt6_get_cookie((struct rt6_info *)dst);
177 	sk_setup_caps(sk, dst);
178 	np->daddr_cache = daddr;
179 #ifdef CONFIG_IPV6_SUBTREES
180 	np->saddr_cache = saddr;
181 #endif
182 }
183 
184 static inline bool ipv6_unicast_destination(const struct sk_buff *skb)
185 {
186 	struct rt6_info *rt = (struct rt6_info *) skb_dst(skb);
187 
188 	return rt->rt6i_flags & RTF_LOCAL;
189 }
190 
191 static inline bool ipv6_anycast_destination(const struct dst_entry *dst,
192 					    const struct in6_addr *daddr)
193 {
194 	struct rt6_info *rt = (struct rt6_info *)dst;
195 
196 	return rt->rt6i_flags & RTF_ANYCAST ||
197 		(rt->rt6i_dst.plen != 128 &&
198 		 ipv6_addr_equal(&rt->rt6i_dst.addr, daddr));
199 }
200 
201 int ip6_fragment(struct net *net, struct sock *sk, struct sk_buff *skb,
202 		 int (*output)(struct net *, struct sock *, struct sk_buff *));
203 
204 static inline int ip6_skb_dst_mtu(struct sk_buff *skb)
205 {
206 	struct ipv6_pinfo *np = skb->sk && !dev_recursion_level() ?
207 				inet6_sk(skb->sk) : NULL;
208 
209 	return (np && np->pmtudisc >= IPV6_PMTUDISC_PROBE) ?
210 	       skb_dst(skb)->dev->mtu : dst_mtu(skb_dst(skb));
211 }
212 
213 static inline bool ip6_sk_accept_pmtu(const struct sock *sk)
214 {
215 	return inet6_sk(sk)->pmtudisc != IPV6_PMTUDISC_INTERFACE &&
216 	       inet6_sk(sk)->pmtudisc != IPV6_PMTUDISC_OMIT;
217 }
218 
219 static inline bool ip6_sk_ignore_df(const struct sock *sk)
220 {
221 	return inet6_sk(sk)->pmtudisc < IPV6_PMTUDISC_DO ||
222 	       inet6_sk(sk)->pmtudisc == IPV6_PMTUDISC_OMIT;
223 }
224 
225 static inline struct in6_addr *rt6_nexthop(struct rt6_info *rt,
226 					   struct in6_addr *daddr)
227 {
228 	if (rt->rt6i_flags & RTF_GATEWAY)
229 		return &rt->rt6i_gateway;
230 	else if (unlikely(rt->rt6i_flags & RTF_CACHE))
231 		return &rt->rt6i_dst.addr;
232 	else
233 		return daddr;
234 }
235 
236 #endif
237