xref: /linux/include/net/dst_metadata.h (revision 83a37b3292f4aca799b355179ad6fbdd78a08e10)
1 #ifndef __NET_DST_METADATA_H
2 #define __NET_DST_METADATA_H 1
3 
4 #include <linux/skbuff.h>
5 #include <net/ip_tunnels.h>
6 #include <net/dst.h>
7 
8 enum metadata_type {
9 	METADATA_IP_TUNNEL,
10 	METADATA_HW_PORT_MUX,
11 };
12 
13 struct hw_port_info {
14 	struct net_device *lower_dev;
15 	u32 port_id;
16 };
17 
18 struct metadata_dst {
19 	struct dst_entry		dst;
20 	enum metadata_type		type;
21 	union {
22 		struct ip_tunnel_info	tun_info;
23 		struct hw_port_info	port_info;
24 	} u;
25 };
26 
27 static inline struct metadata_dst *skb_metadata_dst(const struct sk_buff *skb)
28 {
29 	struct metadata_dst *md_dst = (struct metadata_dst *) skb_dst(skb);
30 
31 	if (md_dst && md_dst->dst.flags & DST_METADATA)
32 		return md_dst;
33 
34 	return NULL;
35 }
36 
37 static inline struct ip_tunnel_info *
38 skb_tunnel_info(const struct sk_buff *skb)
39 {
40 	struct metadata_dst *md_dst = skb_metadata_dst(skb);
41 	struct dst_entry *dst;
42 
43 	if (md_dst && md_dst->type == METADATA_IP_TUNNEL)
44 		return &md_dst->u.tun_info;
45 
46 	dst = skb_dst(skb);
47 	if (dst && dst->lwtstate)
48 		return lwt_tun_info(dst->lwtstate);
49 
50 	return NULL;
51 }
52 
53 static inline bool skb_valid_dst(const struct sk_buff *skb)
54 {
55 	struct dst_entry *dst = skb_dst(skb);
56 
57 	return dst && !(dst->flags & DST_METADATA);
58 }
59 
60 static inline int skb_metadata_dst_cmp(const struct sk_buff *skb_a,
61 				       const struct sk_buff *skb_b)
62 {
63 	const struct metadata_dst *a, *b;
64 
65 	if (!(skb_a->_skb_refdst | skb_b->_skb_refdst))
66 		return 0;
67 
68 	a = (const struct metadata_dst *) skb_dst(skb_a);
69 	b = (const struct metadata_dst *) skb_dst(skb_b);
70 
71 	if (!a != !b || a->type != b->type)
72 		return 1;
73 
74 	switch (a->type) {
75 	case METADATA_HW_PORT_MUX:
76 		return memcmp(&a->u.port_info, &b->u.port_info,
77 			      sizeof(a->u.port_info));
78 	case METADATA_IP_TUNNEL:
79 		return memcmp(&a->u.tun_info, &b->u.tun_info,
80 			      sizeof(a->u.tun_info) +
81 					 a->u.tun_info.options_len);
82 	default:
83 		return 1;
84 	}
85 }
86 
87 void metadata_dst_free(struct metadata_dst *);
88 struct metadata_dst *metadata_dst_alloc(u8 optslen, enum metadata_type type,
89 					gfp_t flags);
90 void metadata_dst_free_percpu(struct metadata_dst __percpu *md_dst);
91 struct metadata_dst __percpu *
92 metadata_dst_alloc_percpu(u8 optslen, enum metadata_type type, gfp_t flags);
93 
94 static inline struct metadata_dst *tun_rx_dst(int md_size)
95 {
96 	struct metadata_dst *tun_dst;
97 
98 	tun_dst = metadata_dst_alloc(md_size, METADATA_IP_TUNNEL, GFP_ATOMIC);
99 	if (!tun_dst)
100 		return NULL;
101 
102 	tun_dst->u.tun_info.options_len = 0;
103 	tun_dst->u.tun_info.mode = 0;
104 	return tun_dst;
105 }
106 
107 static inline struct metadata_dst *tun_dst_unclone(struct sk_buff *skb)
108 {
109 	struct metadata_dst *md_dst = skb_metadata_dst(skb);
110 	int md_size;
111 	struct metadata_dst *new_md;
112 
113 	if (!md_dst || md_dst->type != METADATA_IP_TUNNEL)
114 		return ERR_PTR(-EINVAL);
115 
116 	md_size = md_dst->u.tun_info.options_len;
117 	new_md = metadata_dst_alloc(md_size, METADATA_IP_TUNNEL, GFP_ATOMIC);
118 	if (!new_md)
119 		return ERR_PTR(-ENOMEM);
120 
121 	memcpy(&new_md->u.tun_info, &md_dst->u.tun_info,
122 	       sizeof(struct ip_tunnel_info) + md_size);
123 	skb_dst_drop(skb);
124 	dst_hold(&new_md->dst);
125 	skb_dst_set(skb, &new_md->dst);
126 	return new_md;
127 }
128 
129 static inline struct ip_tunnel_info *skb_tunnel_info_unclone(struct sk_buff *skb)
130 {
131 	struct metadata_dst *dst;
132 
133 	dst = tun_dst_unclone(skb);
134 	if (IS_ERR(dst))
135 		return NULL;
136 
137 	return &dst->u.tun_info;
138 }
139 
140 static inline struct metadata_dst *__ip_tun_set_dst(__be32 saddr,
141 						    __be32 daddr,
142 						    __u8 tos, __u8 ttl,
143 						    __be16 tp_dst,
144 						    __be16 flags,
145 						    __be64 tunnel_id,
146 						    int md_size)
147 {
148 	struct metadata_dst *tun_dst;
149 
150 	tun_dst = tun_rx_dst(md_size);
151 	if (!tun_dst)
152 		return NULL;
153 
154 	ip_tunnel_key_init(&tun_dst->u.tun_info.key,
155 			   saddr, daddr, tos, ttl,
156 			   0, 0, tp_dst, tunnel_id, flags);
157 	return tun_dst;
158 }
159 
160 static inline struct metadata_dst *ip_tun_rx_dst(struct sk_buff *skb,
161 						 __be16 flags,
162 						 __be64 tunnel_id,
163 						 int md_size)
164 {
165 	const struct iphdr *iph = ip_hdr(skb);
166 
167 	return __ip_tun_set_dst(iph->saddr, iph->daddr, iph->tos, iph->ttl,
168 				0, flags, tunnel_id, md_size);
169 }
170 
171 static inline struct metadata_dst *__ipv6_tun_set_dst(const struct in6_addr *saddr,
172 						      const struct in6_addr *daddr,
173 						      __u8 tos, __u8 ttl,
174 						      __be16 tp_dst,
175 						      __be32 label,
176 						      __be16 flags,
177 						      __be64 tunnel_id,
178 						      int md_size)
179 {
180 	struct metadata_dst *tun_dst;
181 	struct ip_tunnel_info *info;
182 
183 	tun_dst = tun_rx_dst(md_size);
184 	if (!tun_dst)
185 		return NULL;
186 
187 	info = &tun_dst->u.tun_info;
188 	info->mode = IP_TUNNEL_INFO_IPV6;
189 	info->key.tun_flags = flags;
190 	info->key.tun_id = tunnel_id;
191 	info->key.tp_src = 0;
192 	info->key.tp_dst = tp_dst;
193 
194 	info->key.u.ipv6.src = *saddr;
195 	info->key.u.ipv6.dst = *daddr;
196 
197 	info->key.tos = tos;
198 	info->key.ttl = ttl;
199 	info->key.label = label;
200 
201 	return tun_dst;
202 }
203 
204 static inline struct metadata_dst *ipv6_tun_rx_dst(struct sk_buff *skb,
205 						   __be16 flags,
206 						   __be64 tunnel_id,
207 						   int md_size)
208 {
209 	const struct ipv6hdr *ip6h = ipv6_hdr(skb);
210 
211 	return __ipv6_tun_set_dst(&ip6h->saddr, &ip6h->daddr,
212 				  ipv6_get_dsfield(ip6h), ip6h->hop_limit,
213 				  0, ip6_flowlabel(ip6h), flags, tunnel_id,
214 				  md_size);
215 }
216 #endif /* __NET_DST_METADATA_H */
217