xref: /openbmc/linux/include/net/dst_metadata.h (revision 3213486f)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __NET_DST_METADATA_H
3 #define __NET_DST_METADATA_H 1
4 
5 #include <linux/skbuff.h>
6 #include <net/ip_tunnels.h>
7 #include <net/dst.h>
8 
9 enum metadata_type {
10 	METADATA_IP_TUNNEL,
11 	METADATA_HW_PORT_MUX,
12 };
13 
14 struct hw_port_info {
15 	struct net_device *lower_dev;
16 	u32 port_id;
17 };
18 
19 struct metadata_dst {
20 	struct dst_entry		dst;
21 	enum metadata_type		type;
22 	union {
23 		struct ip_tunnel_info	tun_info;
24 		struct hw_port_info	port_info;
25 	} u;
26 };
27 
28 static inline struct metadata_dst *skb_metadata_dst(const struct sk_buff *skb)
29 {
30 	struct metadata_dst *md_dst = (struct metadata_dst *) skb_dst(skb);
31 
32 	if (md_dst && md_dst->dst.flags & DST_METADATA)
33 		return md_dst;
34 
35 	return NULL;
36 }
37 
38 static inline struct ip_tunnel_info *
39 skb_tunnel_info(const struct sk_buff *skb)
40 {
41 	struct metadata_dst *md_dst = skb_metadata_dst(skb);
42 	struct dst_entry *dst;
43 
44 	if (md_dst && md_dst->type == METADATA_IP_TUNNEL)
45 		return &md_dst->u.tun_info;
46 
47 	dst = skb_dst(skb);
48 	if (dst && dst->lwtstate)
49 		return lwt_tun_info(dst->lwtstate);
50 
51 	return NULL;
52 }
53 
54 static inline bool skb_valid_dst(const struct sk_buff *skb)
55 {
56 	struct dst_entry *dst = skb_dst(skb);
57 
58 	return dst && !(dst->flags & DST_METADATA);
59 }
60 
61 static inline int skb_metadata_dst_cmp(const struct sk_buff *skb_a,
62 				       const struct sk_buff *skb_b)
63 {
64 	const struct metadata_dst *a, *b;
65 
66 	if (!(skb_a->_skb_refdst | skb_b->_skb_refdst))
67 		return 0;
68 
69 	a = (const struct metadata_dst *) skb_dst(skb_a);
70 	b = (const struct metadata_dst *) skb_dst(skb_b);
71 
72 	if (!a != !b || a->type != b->type)
73 		return 1;
74 
75 	switch (a->type) {
76 	case METADATA_HW_PORT_MUX:
77 		return memcmp(&a->u.port_info, &b->u.port_info,
78 			      sizeof(a->u.port_info));
79 	case METADATA_IP_TUNNEL:
80 		return memcmp(&a->u.tun_info, &b->u.tun_info,
81 			      sizeof(a->u.tun_info) +
82 					 a->u.tun_info.options_len);
83 	default:
84 		return 1;
85 	}
86 }
87 
88 void metadata_dst_free(struct metadata_dst *);
89 struct metadata_dst *metadata_dst_alloc(u8 optslen, enum metadata_type type,
90 					gfp_t flags);
91 void metadata_dst_free_percpu(struct metadata_dst __percpu *md_dst);
92 struct metadata_dst __percpu *
93 metadata_dst_alloc_percpu(u8 optslen, enum metadata_type type, gfp_t flags);
94 
95 static inline struct metadata_dst *tun_rx_dst(int md_size)
96 {
97 	struct metadata_dst *tun_dst;
98 
99 	tun_dst = metadata_dst_alloc(md_size, METADATA_IP_TUNNEL, GFP_ATOMIC);
100 	if (!tun_dst)
101 		return NULL;
102 
103 	tun_dst->u.tun_info.options_len = 0;
104 	tun_dst->u.tun_info.mode = 0;
105 	return tun_dst;
106 }
107 
108 static inline struct metadata_dst *tun_dst_unclone(struct sk_buff *skb)
109 {
110 	struct metadata_dst *md_dst = skb_metadata_dst(skb);
111 	int md_size;
112 	struct metadata_dst *new_md;
113 
114 	if (!md_dst || md_dst->type != METADATA_IP_TUNNEL)
115 		return ERR_PTR(-EINVAL);
116 
117 	md_size = md_dst->u.tun_info.options_len;
118 	new_md = metadata_dst_alloc(md_size, METADATA_IP_TUNNEL, GFP_ATOMIC);
119 	if (!new_md)
120 		return ERR_PTR(-ENOMEM);
121 
122 	memcpy(&new_md->u.tun_info, &md_dst->u.tun_info,
123 	       sizeof(struct ip_tunnel_info) + md_size);
124 	skb_dst_drop(skb);
125 	dst_hold(&new_md->dst);
126 	skb_dst_set(skb, &new_md->dst);
127 	return new_md;
128 }
129 
130 static inline struct ip_tunnel_info *skb_tunnel_info_unclone(struct sk_buff *skb)
131 {
132 	struct metadata_dst *dst;
133 
134 	dst = tun_dst_unclone(skb);
135 	if (IS_ERR(dst))
136 		return NULL;
137 
138 	return &dst->u.tun_info;
139 }
140 
141 static inline struct metadata_dst *__ip_tun_set_dst(__be32 saddr,
142 						    __be32 daddr,
143 						    __u8 tos, __u8 ttl,
144 						    __be16 tp_dst,
145 						    __be16 flags,
146 						    __be64 tunnel_id,
147 						    int md_size)
148 {
149 	struct metadata_dst *tun_dst;
150 
151 	tun_dst = tun_rx_dst(md_size);
152 	if (!tun_dst)
153 		return NULL;
154 
155 	ip_tunnel_key_init(&tun_dst->u.tun_info.key,
156 			   saddr, daddr, tos, ttl,
157 			   0, 0, tp_dst, tunnel_id, flags);
158 	return tun_dst;
159 }
160 
161 static inline struct metadata_dst *ip_tun_rx_dst(struct sk_buff *skb,
162 						 __be16 flags,
163 						 __be64 tunnel_id,
164 						 int md_size)
165 {
166 	const struct iphdr *iph = ip_hdr(skb);
167 
168 	return __ip_tun_set_dst(iph->saddr, iph->daddr, iph->tos, iph->ttl,
169 				0, flags, tunnel_id, md_size);
170 }
171 
172 static inline struct metadata_dst *__ipv6_tun_set_dst(const struct in6_addr *saddr,
173 						      const struct in6_addr *daddr,
174 						      __u8 tos, __u8 ttl,
175 						      __be16 tp_dst,
176 						      __be32 label,
177 						      __be16 flags,
178 						      __be64 tunnel_id,
179 						      int md_size)
180 {
181 	struct metadata_dst *tun_dst;
182 	struct ip_tunnel_info *info;
183 
184 	tun_dst = tun_rx_dst(md_size);
185 	if (!tun_dst)
186 		return NULL;
187 
188 	info = &tun_dst->u.tun_info;
189 	info->mode = IP_TUNNEL_INFO_IPV6;
190 	info->key.tun_flags = flags;
191 	info->key.tun_id = tunnel_id;
192 	info->key.tp_src = 0;
193 	info->key.tp_dst = tp_dst;
194 
195 	info->key.u.ipv6.src = *saddr;
196 	info->key.u.ipv6.dst = *daddr;
197 
198 	info->key.tos = tos;
199 	info->key.ttl = ttl;
200 	info->key.label = label;
201 
202 	return tun_dst;
203 }
204 
205 static inline struct metadata_dst *ipv6_tun_rx_dst(struct sk_buff *skb,
206 						   __be16 flags,
207 						   __be64 tunnel_id,
208 						   int md_size)
209 {
210 	const struct ipv6hdr *ip6h = ipv6_hdr(skb);
211 
212 	return __ipv6_tun_set_dst(&ip6h->saddr, &ip6h->daddr,
213 				  ipv6_get_dsfield(ip6h), ip6h->hop_limit,
214 				  0, ip6_flowlabel(ip6h), flags, tunnel_id,
215 				  md_size);
216 }
217 #endif /* __NET_DST_METADATA_H */
218