xref: /openbmc/linux/include/net/ip6_route.h (revision 77a87824)
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 
36 /* We do not (yet ?) support IPv6 jumbograms (RFC 2675)
37  * Unlike IPv4, hdr->seg_len doesn't include the IPv6 header
38  */
39 #define IP6_MAX_MTU (0xFFFF + sizeof(struct ipv6hdr))
40 
41 /*
42  * rt6_srcprefs2flags() and rt6_flags2srcprefs() translate
43  * between IPV6_ADDR_PREFERENCES socket option values
44  *	IPV6_PREFER_SRC_TMP    = 0x1
45  *	IPV6_PREFER_SRC_PUBLIC = 0x2
46  *	IPV6_PREFER_SRC_COA    = 0x4
47  * and above RT6_LOOKUP_F_SRCPREF_xxx flags.
48  */
49 static inline int rt6_srcprefs2flags(unsigned int srcprefs)
50 {
51 	/* No need to bitmask because srcprefs have only 3 bits. */
52 	return srcprefs << 3;
53 }
54 
55 static inline unsigned int rt6_flags2srcprefs(int flags)
56 {
57 	return (flags >> 3) & 7;
58 }
59 
60 static inline bool rt6_need_strict(const struct in6_addr *daddr)
61 {
62 	return ipv6_addr_type(daddr) &
63 		(IPV6_ADDR_MULTICAST | IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
64 }
65 
66 void ip6_route_input(struct sk_buff *skb);
67 
68 struct dst_entry *ip6_route_output_flags(struct net *net, const struct sock *sk,
69 					 struct flowi6 *fl6, int flags);
70 
71 static inline struct dst_entry *ip6_route_output(struct net *net,
72 						 const struct sock *sk,
73 						 struct flowi6 *fl6)
74 {
75 	return ip6_route_output_flags(net, sk, fl6, 0);
76 }
77 
78 struct dst_entry *ip6_route_lookup(struct net *net, struct flowi6 *fl6,
79 				   int flags);
80 struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table,
81 			       int ifindex, struct flowi6 *fl6, int flags);
82 
83 int ip6_route_init(void);
84 void ip6_route_cleanup(void);
85 
86 int ipv6_route_ioctl(struct net *net, unsigned int cmd, void __user *arg);
87 
88 int ip6_route_add(struct fib6_config *cfg);
89 int ip6_ins_rt(struct rt6_info *);
90 int ip6_del_rt(struct rt6_info *);
91 
92 static inline int ip6_route_get_saddr(struct net *net, struct rt6_info *rt,
93 				      const struct in6_addr *daddr,
94 				      unsigned int prefs,
95 				      struct in6_addr *saddr)
96 {
97 	struct inet6_dev *idev =
98 			rt ? ip6_dst_idev((struct dst_entry *)rt) : NULL;
99 	int err = 0;
100 
101 	if (rt && rt->rt6i_prefsrc.plen)
102 		*saddr = rt->rt6i_prefsrc.addr;
103 	else
104 		err = ipv6_dev_get_saddr(net, idev ? idev->dev : NULL,
105 					 daddr, prefs, saddr);
106 
107 	return err;
108 }
109 
110 struct rt6_info *rt6_lookup(struct net *net, const struct in6_addr *daddr,
111 			    const struct in6_addr *saddr, int oif, int flags);
112 
113 struct dst_entry *icmp6_dst_alloc(struct net_device *dev, struct flowi6 *fl6);
114 int icmp6_dst_gc(void);
115 
116 void fib6_force_start_gc(struct net *net);
117 
118 struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev,
119 				    const struct in6_addr *addr, bool anycast);
120 
121 struct rt6_info *ip6_dst_alloc(struct net *net, struct net_device *dev,
122 			       int flags);
123 
124 /*
125  *	support functions for ND
126  *
127  */
128 struct rt6_info *rt6_get_dflt_router(const struct in6_addr *addr,
129 				     struct net_device *dev);
130 struct rt6_info *rt6_add_dflt_router(const struct in6_addr *gwaddr,
131 				     struct net_device *dev, unsigned int pref);
132 
133 void rt6_purge_dflt_routers(struct net *net);
134 
135 int rt6_route_rcv(struct net_device *dev, u8 *opt, int len,
136 		  const struct in6_addr *gwaddr);
137 
138 void ip6_update_pmtu(struct sk_buff *skb, struct net *net, __be32 mtu, int oif,
139 		     u32 mark);
140 void ip6_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, __be32 mtu);
141 void ip6_redirect(struct sk_buff *skb, struct net *net, int oif, u32 mark);
142 void ip6_redirect_no_header(struct sk_buff *skb, struct net *net, int oif,
143 			    u32 mark);
144 void ip6_sk_redirect(struct sk_buff *skb, struct sock *sk);
145 
146 struct netlink_callback;
147 
148 struct rt6_rtnl_dump_arg {
149 	struct sk_buff *skb;
150 	struct netlink_callback *cb;
151 	struct net *net;
152 };
153 
154 int rt6_dump_route(struct rt6_info *rt, void *p_arg);
155 void rt6_ifdown(struct net *net, struct net_device *dev);
156 void rt6_mtu_change(struct net_device *dev, unsigned int mtu);
157 void rt6_remove_prefsrc(struct inet6_ifaddr *ifp);
158 void rt6_clean_tohost(struct net *net, struct in6_addr *gateway);
159 
160 
161 /*
162  *	Store a destination cache entry in a socket
163  */
164 static inline void ip6_dst_store(struct sock *sk, struct dst_entry *dst,
165 				 const struct in6_addr *daddr,
166 				 const struct in6_addr *saddr)
167 {
168 	struct ipv6_pinfo *np = inet6_sk(sk);
169 
170 	np->dst_cookie = rt6_get_cookie((struct rt6_info *)dst);
171 	sk_setup_caps(sk, dst);
172 	np->daddr_cache = daddr;
173 #ifdef CONFIG_IPV6_SUBTREES
174 	np->saddr_cache = saddr;
175 #endif
176 }
177 
178 static inline bool ipv6_unicast_destination(const struct sk_buff *skb)
179 {
180 	struct rt6_info *rt = (struct rt6_info *) skb_dst(skb);
181 
182 	return rt->rt6i_flags & RTF_LOCAL;
183 }
184 
185 static inline bool ipv6_anycast_destination(const struct dst_entry *dst,
186 					    const struct in6_addr *daddr)
187 {
188 	struct rt6_info *rt = (struct rt6_info *)dst;
189 
190 	return rt->rt6i_flags & RTF_ANYCAST ||
191 		(rt->rt6i_dst.plen != 128 &&
192 		 ipv6_addr_equal(&rt->rt6i_dst.addr, daddr));
193 }
194 
195 int ip6_fragment(struct net *net, struct sock *sk, struct sk_buff *skb,
196 		 int (*output)(struct net *, struct sock *, struct sk_buff *));
197 
198 static inline int ip6_skb_dst_mtu(struct sk_buff *skb)
199 {
200 	struct ipv6_pinfo *np = skb->sk && !dev_recursion_level() ?
201 				inet6_sk(skb->sk) : NULL;
202 
203 	return (np && np->pmtudisc >= IPV6_PMTUDISC_PROBE) ?
204 	       skb_dst(skb)->dev->mtu : dst_mtu(skb_dst(skb));
205 }
206 
207 static inline bool ip6_sk_accept_pmtu(const struct sock *sk)
208 {
209 	return inet6_sk(sk)->pmtudisc != IPV6_PMTUDISC_INTERFACE &&
210 	       inet6_sk(sk)->pmtudisc != IPV6_PMTUDISC_OMIT;
211 }
212 
213 static inline bool ip6_sk_ignore_df(const struct sock *sk)
214 {
215 	return inet6_sk(sk)->pmtudisc < IPV6_PMTUDISC_DO ||
216 	       inet6_sk(sk)->pmtudisc == IPV6_PMTUDISC_OMIT;
217 }
218 
219 static inline struct in6_addr *rt6_nexthop(struct rt6_info *rt,
220 					   struct in6_addr *daddr)
221 {
222 	if (rt->rt6i_flags & RTF_GATEWAY)
223 		return &rt->rt6i_gateway;
224 	else if (unlikely(rt->rt6i_flags & RTF_CACHE))
225 		return &rt->rt6i_dst.addr;
226 	else
227 		return daddr;
228 }
229 
230 #endif
231