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
9enum metadata_type {
10 METADATA_IP_TUNNEL,
11 METADATA_HW_PORT_MUX,
12};
13
14struct hw_port_info {
15 struct net_device *lower_dev;
16 u32 port_id;
17};
18
19struct 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
28static 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
38static inline struct ip_tunnel_info *
39skb_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 (dst->lwtstate->type == LWTUNNEL_ENCAP_IP ||
50 dst->lwtstate->type == LWTUNNEL_ENCAP_IP6))
51 return lwt_tun_info(dst->lwtstate);
52
53 return NULL;
54}
55
56static inline bool skb_valid_dst(const struct sk_buff *skb)
57{
58 struct dst_entry *dst = skb_dst(skb);
59
60 return dst && !(dst->flags & DST_METADATA);
61}
62
63static inline int skb_metadata_dst_cmp(const struct sk_buff *skb_a,
64 const struct sk_buff *skb_b)
65{
66 const struct metadata_dst *a, *b;
67
68 if (!(skb_a->_skb_refdst | skb_b->_skb_refdst))
69 return 0;
70
71 a = (const struct metadata_dst *) skb_dst(skb_a);
72 b = (const struct metadata_dst *) skb_dst(skb_b);
73
74 if (!a != !b || a->type != b->type)
75 return 1;
76
77 switch (a->type) {
78 case METADATA_HW_PORT_MUX:
79 return memcmp(&a->u.port_info, &b->u.port_info,
80 sizeof(a->u.port_info));
81 case METADATA_IP_TUNNEL:
82 return memcmp(&a->u.tun_info, &b->u.tun_info,
83 sizeof(a->u.tun_info) +
84 a->u.tun_info.options_len);
85 default:
86 return 1;
87 }
88}
89
90void metadata_dst_free(struct metadata_dst *);
91struct metadata_dst *metadata_dst_alloc(u8 optslen, enum metadata_type type,
92 gfp_t flags);
93void metadata_dst_free_percpu(struct metadata_dst __percpu *md_dst);
94struct metadata_dst __percpu *
95metadata_dst_alloc_percpu(u8 optslen, enum metadata_type type, gfp_t flags);
96
97static inline struct metadata_dst *tun_rx_dst(int md_size)
98{
99 struct metadata_dst *tun_dst;
100
101 tun_dst = metadata_dst_alloc(md_size, METADATA_IP_TUNNEL, GFP_ATOMIC);
102 if (!tun_dst)
103 return NULL;
104
105 tun_dst->u.tun_info.options_len = 0;
106 tun_dst->u.tun_info.mode = 0;
107 return tun_dst;
108}
109
110static inline struct metadata_dst *tun_dst_unclone(struct sk_buff *skb)
111{
112 struct metadata_dst *md_dst = skb_metadata_dst(skb);
113 int md_size;
114 struct metadata_dst *new_md;
115
116 if (!md_dst || md_dst->type != METADATA_IP_TUNNEL)
117 return ERR_PTR(-EINVAL);
118
119 md_size = md_dst->u.tun_info.options_len;
120 new_md = metadata_dst_alloc(md_size, METADATA_IP_TUNNEL, GFP_ATOMIC);
121 if (!new_md)
122 return ERR_PTR(-ENOMEM);
123
124 memcpy(&new_md->u.tun_info, &md_dst->u.tun_info,
125 sizeof(struct ip_tunnel_info) + md_size);
126#ifdef CONFIG_DST_CACHE
127 /* Unclone the dst cache if there is one */
128 if (new_md->u.tun_info.dst_cache.cache) {
129 int ret;
130
131 ret = dst_cache_init(&new_md->u.tun_info.dst_cache, GFP_ATOMIC);
132 if (ret) {
133 metadata_dst_free(new_md);
134 return ERR_PTR(ret);
135 }
136 }
137#endif
138
139 skb_dst_drop(skb);
140 skb_dst_set(skb, &new_md->dst);
141 return new_md;
142}
143
144static inline struct ip_tunnel_info *skb_tunnel_info_unclone(struct sk_buff *skb)
145{
146 struct metadata_dst *dst;
147
148 dst = tun_dst_unclone(skb);
149 if (IS_ERR(dst))
150 return NULL;
151
152 return &dst->u.tun_info;
153}
154
155static inline struct metadata_dst *__ip_tun_set_dst(__be32 saddr,
156 __be32 daddr,
157 __u8 tos, __u8 ttl,
158 __be16 tp_dst,
159 __be16 flags,
160 __be64 tunnel_id,
161 int md_size)
162{
163 struct metadata_dst *tun_dst;
164
165 tun_dst = tun_rx_dst(md_size);
166 if (!tun_dst)
167 return NULL;
168
169 ip_tunnel_key_init(&tun_dst->u.tun_info.key,
170 saddr, daddr, tos, ttl,
171 0, 0, tp_dst, tunnel_id, flags);
172 return tun_dst;
173}
174
175static inline struct metadata_dst *ip_tun_rx_dst(struct sk_buff *skb,
176 __be16 flags,
177 __be64 tunnel_id,
178 int md_size)
179{
180 const struct iphdr *iph = ip_hdr(skb);
181
182 return __ip_tun_set_dst(iph->saddr, iph->daddr, iph->tos, iph->ttl,
183 0, flags, tunnel_id, md_size);
184}
185
186static inline struct metadata_dst *__ipv6_tun_set_dst(const struct in6_addr *saddr,
187 const struct in6_addr *daddr,
188 __u8 tos, __u8 ttl,
189 __be16 tp_dst,
190 __be32 label,
191 __be16 flags,
192 __be64 tunnel_id,
193 int md_size)
194{
195 struct metadata_dst *tun_dst;
196 struct ip_tunnel_info *info;
197
198 tun_dst = tun_rx_dst(md_size);
199 if (!tun_dst)
200 return NULL;
201
202 info = &tun_dst->u.tun_info;
203 info->mode = IP_TUNNEL_INFO_IPV6;
204 info->key.tun_flags = flags;
205 info->key.tun_id = tunnel_id;
206 info->key.tp_src = 0;
207 info->key.tp_dst = tp_dst;
208
209 info->key.u.ipv6.src = *saddr;
210 info->key.u.ipv6.dst = *daddr;
211
212 info->key.tos = tos;
213 info->key.ttl = ttl;
214 info->key.label = label;
215
216 return tun_dst;
217}
218
219static inline struct metadata_dst *ipv6_tun_rx_dst(struct sk_buff *skb,
220 __be16 flags,
221 __be64 tunnel_id,
222 int md_size)
223{
224 const struct ipv6hdr *ip6h = ipv6_hdr(skb);
225
226 return __ipv6_tun_set_dst(&ip6h->saddr, &ip6h->daddr,
227 ipv6_get_dsfield(ip6h), ip6h->hop_limit,
228 0, ip6_flowlabel(ip6h), flags, tunnel_id,
229 md_size);
230}
231#endif /* __NET_DST_METADATA_H */
232

source code of linux/include/net/dst_metadata.h