xref: /openbmc/linux/include/net/ndisc.h (revision 95e9fd10)
1 #ifndef _NDISC_H
2 #define _NDISC_H
3 
4 /*
5  *	ICMP codes for neighbour discovery messages
6  */
7 
8 #define NDISC_ROUTER_SOLICITATION	133
9 #define NDISC_ROUTER_ADVERTISEMENT	134
10 #define NDISC_NEIGHBOUR_SOLICITATION	135
11 #define NDISC_NEIGHBOUR_ADVERTISEMENT	136
12 #define NDISC_REDIRECT			137
13 
14 /*
15  * Router type: cross-layer information from link-layer to
16  * IPv6 layer reported by certain link types (e.g., RFC4214).
17  */
18 #define NDISC_NODETYPE_UNSPEC		0	/* unspecified (default) */
19 #define NDISC_NODETYPE_HOST		1	/* host or unauthorized router */
20 #define NDISC_NODETYPE_NODEFAULT	2	/* non-default router */
21 #define NDISC_NODETYPE_DEFAULT		3	/* default router */
22 
23 /*
24  *	ndisc options
25  */
26 
27 enum {
28 	__ND_OPT_PREFIX_INFO_END = 0,
29 	ND_OPT_SOURCE_LL_ADDR = 1,	/* RFC2461 */
30 	ND_OPT_TARGET_LL_ADDR = 2,	/* RFC2461 */
31 	ND_OPT_PREFIX_INFO = 3,		/* RFC2461 */
32 	ND_OPT_REDIRECT_HDR = 4,	/* RFC2461 */
33 	ND_OPT_MTU = 5,			/* RFC2461 */
34 	__ND_OPT_ARRAY_MAX,
35 	ND_OPT_ROUTE_INFO = 24,		/* RFC4191 */
36 	ND_OPT_RDNSS = 25,		/* RFC5006 */
37 	ND_OPT_DNSSL = 31,		/* RFC6106 */
38 	__ND_OPT_MAX
39 };
40 
41 #define MAX_RTR_SOLICITATION_DELAY	HZ
42 
43 #define ND_REACHABLE_TIME		(30*HZ)
44 #define ND_RETRANS_TIMER		HZ
45 
46 #include <linux/compiler.h>
47 #include <linux/icmpv6.h>
48 #include <linux/in6.h>
49 #include <linux/types.h>
50 #include <linux/if_arp.h>
51 #include <linux/netdevice.h>
52 
53 #include <net/neighbour.h>
54 
55 struct ctl_table;
56 struct inet6_dev;
57 struct net_device;
58 struct net_proto_family;
59 struct sk_buff;
60 
61 extern struct neigh_table nd_tbl;
62 
63 struct nd_msg {
64         struct icmp6hdr	icmph;
65         struct in6_addr	target;
66 	__u8		opt[0];
67 };
68 
69 struct rs_msg {
70 	struct icmp6hdr	icmph;
71 	__u8		opt[0];
72 };
73 
74 struct ra_msg {
75         struct icmp6hdr		icmph;
76 	__be32			reachable_time;
77 	__be32			retrans_timer;
78 };
79 
80 struct nd_opt_hdr {
81 	__u8		nd_opt_type;
82 	__u8		nd_opt_len;
83 } __packed;
84 
85 /* ND options */
86 struct ndisc_options {
87 	struct nd_opt_hdr *nd_opt_array[__ND_OPT_ARRAY_MAX];
88 #ifdef CONFIG_IPV6_ROUTE_INFO
89 	struct nd_opt_hdr *nd_opts_ri;
90 	struct nd_opt_hdr *nd_opts_ri_end;
91 #endif
92 	struct nd_opt_hdr *nd_useropts;
93 	struct nd_opt_hdr *nd_useropts_end;
94 };
95 
96 #define nd_opts_src_lladdr	nd_opt_array[ND_OPT_SOURCE_LL_ADDR]
97 #define nd_opts_tgt_lladdr	nd_opt_array[ND_OPT_TARGET_LL_ADDR]
98 #define nd_opts_pi		nd_opt_array[ND_OPT_PREFIX_INFO]
99 #define nd_opts_pi_end		nd_opt_array[__ND_OPT_PREFIX_INFO_END]
100 #define nd_opts_rh		nd_opt_array[ND_OPT_REDIRECT_HDR]
101 #define nd_opts_mtu		nd_opt_array[ND_OPT_MTU]
102 
103 #define NDISC_OPT_SPACE(len) (((len)+2+7)&~7)
104 
105 extern struct ndisc_options *ndisc_parse_options(u8 *opt, int opt_len,
106 						 struct ndisc_options *ndopts);
107 
108 /*
109  * Return the padding between the option length and the start of the
110  * link addr.  Currently only IP-over-InfiniBand needs this, although
111  * if RFC 3831 IPv6-over-Fibre Channel is ever implemented it may
112  * also need a pad of 2.
113  */
114 static int ndisc_addr_option_pad(unsigned short type)
115 {
116 	switch (type) {
117 	case ARPHRD_INFINIBAND: return 2;
118 	default:                return 0;
119 	}
120 }
121 
122 static inline u8 *ndisc_opt_addr_data(struct nd_opt_hdr *p,
123 				      struct net_device *dev)
124 {
125 	u8 *lladdr = (u8 *)(p + 1);
126 	int lladdrlen = p->nd_opt_len << 3;
127 	int prepad = ndisc_addr_option_pad(dev->type);
128 	if (lladdrlen != NDISC_OPT_SPACE(dev->addr_len + prepad))
129 		return NULL;
130 	return lladdr + prepad;
131 }
132 
133 static inline u32 ndisc_hashfn(const void *pkey, const struct net_device *dev, __u32 *hash_rnd)
134 {
135 	const u32 *p32 = pkey;
136 
137 	return (((p32[0] ^ dev->ifindex) * hash_rnd[0]) +
138 		(p32[1] * hash_rnd[1]) +
139 		(p32[2] * hash_rnd[2]) +
140 		(p32[3] * hash_rnd[3]));
141 }
142 
143 static inline struct neighbour *__ipv6_neigh_lookup(struct neigh_table *tbl, struct net_device *dev, const void *pkey)
144 {
145 	struct neigh_hash_table *nht;
146 	const u32 *p32 = pkey;
147 	struct neighbour *n;
148 	u32 hash_val;
149 
150 	rcu_read_lock_bh();
151 	nht = rcu_dereference_bh(tbl->nht);
152 	hash_val = ndisc_hashfn(pkey, dev, nht->hash_rnd) >> (32 - nht->hash_shift);
153 	for (n = rcu_dereference_bh(nht->hash_buckets[hash_val]);
154 	     n != NULL;
155 	     n = rcu_dereference_bh(n->next)) {
156 		u32 *n32 = (u32 *) n->primary_key;
157 		if (n->dev == dev &&
158 		    ((n32[0] ^ p32[0]) | (n32[1] ^ p32[1]) |
159 		     (n32[2] ^ p32[2]) | (n32[3] ^ p32[3])) == 0) {
160 			if (!atomic_inc_not_zero(&n->refcnt))
161 				n = NULL;
162 			break;
163 		}
164 	}
165 	rcu_read_unlock_bh();
166 
167 	return n;
168 }
169 
170 extern int			ndisc_init(void);
171 
172 extern void			ndisc_cleanup(void);
173 
174 extern int			ndisc_rcv(struct sk_buff *skb);
175 
176 extern void			ndisc_send_ns(struct net_device *dev,
177 					      struct neighbour *neigh,
178 					      const struct in6_addr *solicit,
179 					      const struct in6_addr *daddr,
180 					      const struct in6_addr *saddr);
181 
182 extern void			ndisc_send_rs(struct net_device *dev,
183 					      const struct in6_addr *saddr,
184 					      const struct in6_addr *daddr);
185 
186 extern void			ndisc_send_redirect(struct sk_buff *skb,
187 						    const struct in6_addr *target);
188 
189 extern int			ndisc_mc_map(const struct in6_addr *addr, char *buf,
190 					     struct net_device *dev, int dir);
191 
192 extern struct sk_buff		*ndisc_build_skb(struct net_device *dev,
193 						 const struct in6_addr *daddr,
194 						 const struct in6_addr *saddr,
195 						 struct icmp6hdr *icmp6h,
196 						 const struct in6_addr *target,
197 						 int llinfo);
198 
199 extern void			ndisc_send_skb(struct sk_buff *skb,
200 					       struct net_device *dev,
201 					       struct neighbour *neigh,
202 					       const struct in6_addr *daddr,
203 					       const struct in6_addr *saddr,
204 					       struct icmp6hdr *icmp6h);
205 
206 
207 
208 /*
209  *	IGMP
210  */
211 extern int			igmp6_init(void);
212 
213 extern void			igmp6_cleanup(void);
214 
215 extern int			igmp6_event_query(struct sk_buff *skb);
216 
217 extern int			igmp6_event_report(struct sk_buff *skb);
218 
219 
220 #ifdef CONFIG_SYSCTL
221 extern int 			ndisc_ifinfo_sysctl_change(struct ctl_table *ctl,
222 							   int write,
223 							   void __user *buffer,
224 							   size_t *lenp,
225 							   loff_t *ppos);
226 int ndisc_ifinfo_sysctl_strategy(ctl_table *ctl,
227 				 void __user *oldval, size_t __user *oldlenp,
228 				 void __user *newval, size_t newlen);
229 #endif
230 
231 extern void 			inet6_ifinfo_notify(int event,
232 						    struct inet6_dev *idev);
233 
234 #endif
235