xref: /openbmc/linux/include/net/dst_metadata.h (revision 28efb0046512e8a13ed9f9bdf0d68d10bbfbe9cf)
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 struct metadata_dst __percpu *
91 metadata_dst_alloc_percpu(u8 optslen, enum metadata_type type, gfp_t flags);
92 
93 static inline struct metadata_dst *tun_rx_dst(int md_size)
94 {
95 	struct metadata_dst *tun_dst;
96 
97 	tun_dst = metadata_dst_alloc(md_size, METADATA_IP_TUNNEL, GFP_ATOMIC);
98 	if (!tun_dst)
99 		return NULL;
100 
101 	tun_dst->u.tun_info.options_len = 0;
102 	tun_dst->u.tun_info.mode = 0;
103 	return tun_dst;
104 }
105 
106 static inline struct metadata_dst *tun_dst_unclone(struct sk_buff *skb)
107 {
108 	struct metadata_dst *md_dst = skb_metadata_dst(skb);
109 	int md_size;
110 	struct metadata_dst *new_md;
111 
112 	if (!md_dst || md_dst->type != METADATA_IP_TUNNEL)
113 		return ERR_PTR(-EINVAL);
114 
115 	md_size = md_dst->u.tun_info.options_len;
116 	new_md = metadata_dst_alloc(md_size, METADATA_IP_TUNNEL, GFP_ATOMIC);
117 	if (!new_md)
118 		return ERR_PTR(-ENOMEM);
119 
120 	memcpy(&new_md->u.tun_info, &md_dst->u.tun_info,
121 	       sizeof(struct ip_tunnel_info) + md_size);
122 	skb_dst_drop(skb);
123 	dst_hold(&new_md->dst);
124 	skb_dst_set(skb, &new_md->dst);
125 	return new_md;
126 }
127 
128 static inline struct ip_tunnel_info *skb_tunnel_info_unclone(struct sk_buff *skb)
129 {
130 	struct metadata_dst *dst;
131 
132 	dst = tun_dst_unclone(skb);
133 	if (IS_ERR(dst))
134 		return NULL;
135 
136 	return &dst->u.tun_info;
137 }
138 
139 static inline struct metadata_dst *__ip_tun_set_dst(__be32 saddr,
140 						    __be32 daddr,
141 						    __u8 tos, __u8 ttl,
142 						    __be16 tp_dst,
143 						    __be16 flags,
144 						    __be64 tunnel_id,
145 						    int md_size)
146 {
147 	struct metadata_dst *tun_dst;
148 
149 	tun_dst = tun_rx_dst(md_size);
150 	if (!tun_dst)
151 		return NULL;
152 
153 	ip_tunnel_key_init(&tun_dst->u.tun_info.key,
154 			   saddr, daddr, tos, ttl,
155 			   0, 0, tp_dst, tunnel_id, flags);
156 	return tun_dst;
157 }
158 
159 static inline struct metadata_dst *ip_tun_rx_dst(struct sk_buff *skb,
160 						 __be16 flags,
161 						 __be64 tunnel_id,
162 						 int md_size)
163 {
164 	const struct iphdr *iph = ip_hdr(skb);
165 
166 	return __ip_tun_set_dst(iph->saddr, iph->daddr, iph->tos, iph->ttl,
167 				0, flags, tunnel_id, md_size);
168 }
169 
170 static inline struct metadata_dst *__ipv6_tun_set_dst(const struct in6_addr *saddr,
171 						      const struct in6_addr *daddr,
172 						      __u8 tos, __u8 ttl,
173 						      __be16 tp_dst,
174 						      __be32 label,
175 						      __be16 flags,
176 						      __be64 tunnel_id,
177 						      int md_size)
178 {
179 	struct metadata_dst *tun_dst;
180 	struct ip_tunnel_info *info;
181 
182 	tun_dst = tun_rx_dst(md_size);
183 	if (!tun_dst)
184 		return NULL;
185 
186 	info = &tun_dst->u.tun_info;
187 	info->mode = IP_TUNNEL_INFO_IPV6;
188 	info->key.tun_flags = flags;
189 	info->key.tun_id = tunnel_id;
190 	info->key.tp_src = 0;
191 	info->key.tp_dst = tp_dst;
192 
193 	info->key.u.ipv6.src = *saddr;
194 	info->key.u.ipv6.dst = *daddr;
195 
196 	info->key.tos = tos;
197 	info->key.ttl = ttl;
198 	info->key.label = label;
199 
200 	return tun_dst;
201 }
202 
203 static inline struct metadata_dst *ipv6_tun_rx_dst(struct sk_buff *skb,
204 						   __be16 flags,
205 						   __be64 tunnel_id,
206 						   int md_size)
207 {
208 	const struct ipv6hdr *ip6h = ipv6_hdr(skb);
209 
210 	return __ipv6_tun_set_dst(&ip6h->saddr, &ip6h->daddr,
211 				  ipv6_get_dsfield(ip6h), ip6h->hop_limit,
212 				  0, ip6_flowlabel(ip6h), flags, tunnel_id,
213 				  md_size);
214 }
215 #endif /* __NET_DST_METADATA_H */
216