xref: /linux/include/net/dst_metadata.h (revision cbf658dd09419f1ef9de11b9604e950bdd5c170b)
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.h>
7 #include <net/ip_tunnels.h>
8 #include <net/macsec.h>
9 #include <net/dst.h>
10 
11 enum metadata_type {
12 	METADATA_IP_TUNNEL,
13 	METADATA_HW_PORT_MUX,
14 	METADATA_MACSEC,
15 	METADATA_XFRM,
16 };
17 
18 struct hw_port_info {
19 	struct net_device *lower_dev;
20 	u32 port_id;
21 };
22 
23 struct macsec_info {
24 	sci_t sci;
25 };
26 
27 struct xfrm_md_info {
28 	u32 if_id;
29 	int link;
30 	struct dst_entry *dst_orig;
31 };
32 
33 struct metadata_dst {
34 	struct dst_entry		dst;
35 	enum metadata_type		type;
36 	union {
37 		struct ip_tunnel_info	tun_info;
38 		struct hw_port_info	port_info;
39 		struct macsec_info	macsec_info;
40 		struct xfrm_md_info	xfrm_info;
41 	} u;
42 };
43 
skb_metadata_dst(const struct sk_buff * skb)44 static inline struct metadata_dst *skb_metadata_dst(const struct sk_buff *skb)
45 {
46 	struct metadata_dst *md_dst = (struct metadata_dst *) skb_dst(skb);
47 
48 	if (md_dst && md_dst->dst.flags & DST_METADATA)
49 		return md_dst;
50 
51 	return NULL;
52 }
53 
54 static inline struct ip_tunnel_info *
skb_tunnel_info(const struct sk_buff * skb)55 skb_tunnel_info(const struct sk_buff *skb)
56 {
57 	struct metadata_dst *md_dst = skb_metadata_dst(skb);
58 	struct dst_entry *dst;
59 
60 	if (md_dst && md_dst->type == METADATA_IP_TUNNEL)
61 		return &md_dst->u.tun_info;
62 
63 	dst = skb_dst(skb);
64 	if (dst && dst->lwtstate &&
65 	    (dst->lwtstate->type == LWTUNNEL_ENCAP_IP ||
66 	     dst->lwtstate->type == LWTUNNEL_ENCAP_IP6))
67 		return lwt_tun_info(dst->lwtstate);
68 
69 	return NULL;
70 }
71 
lwt_xfrm_info(struct lwtunnel_state * lwt)72 static inline struct xfrm_md_info *lwt_xfrm_info(struct lwtunnel_state *lwt)
73 {
74 	return (struct xfrm_md_info *)lwt->data;
75 }
76 
skb_xfrm_md_info(const struct sk_buff * skb)77 static inline struct xfrm_md_info *skb_xfrm_md_info(const struct sk_buff *skb)
78 {
79 	struct metadata_dst *md_dst = skb_metadata_dst(skb);
80 	struct dst_entry *dst;
81 
82 	if (md_dst && md_dst->type == METADATA_XFRM)
83 		return &md_dst->u.xfrm_info;
84 
85 	dst = skb_dst(skb);
86 	if (dst && dst->lwtstate &&
87 	    dst->lwtstate->type == LWTUNNEL_ENCAP_XFRM)
88 		return lwt_xfrm_info(dst->lwtstate);
89 
90 	return NULL;
91 }
92 
skb_valid_dst(const struct sk_buff * skb)93 static inline bool skb_valid_dst(const struct sk_buff *skb)
94 {
95 	struct dst_entry *dst = skb_dst(skb);
96 
97 	return dst && !(dst->flags & DST_METADATA);
98 }
99 
skb_metadata_dst_cmp(const struct sk_buff * skb_a,const struct sk_buff * skb_b)100 static inline int skb_metadata_dst_cmp(const struct sk_buff *skb_a,
101 				       const struct sk_buff *skb_b)
102 {
103 	const struct metadata_dst *a, *b;
104 
105 	if (!(skb_a->_skb_refdst | skb_b->_skb_refdst))
106 		return 0;
107 
108 	a = (const struct metadata_dst *) skb_dst(skb_a);
109 	b = (const struct metadata_dst *) skb_dst(skb_b);
110 
111 	if (!a != !b || a->type != b->type)
112 		return 1;
113 
114 	switch (a->type) {
115 	case METADATA_HW_PORT_MUX:
116 		return memcmp(&a->u.port_info, &b->u.port_info,
117 			      sizeof(a->u.port_info));
118 	case METADATA_IP_TUNNEL:
119 		return memcmp(&a->u.tun_info, &b->u.tun_info,
120 			      sizeof(a->u.tun_info) +
121 					 a->u.tun_info.options_len);
122 	case METADATA_MACSEC:
123 		return memcmp(&a->u.macsec_info, &b->u.macsec_info,
124 			      sizeof(a->u.macsec_info));
125 	case METADATA_XFRM:
126 		return memcmp(&a->u.xfrm_info, &b->u.xfrm_info,
127 			      sizeof(a->u.xfrm_info));
128 	default:
129 		return 1;
130 	}
131 }
132 
133 void metadata_dst_free(struct metadata_dst *);
134 struct metadata_dst *metadata_dst_alloc(u8 optslen, enum metadata_type type,
135 					gfp_t flags);
136 void metadata_dst_free_percpu(struct metadata_dst __percpu *md_dst);
137 struct metadata_dst __percpu *
138 metadata_dst_alloc_percpu(u8 optslen, enum metadata_type type, gfp_t flags);
139 
tun_rx_dst(int md_size)140 static inline struct metadata_dst *tun_rx_dst(int md_size)
141 {
142 	struct metadata_dst *tun_dst;
143 
144 	tun_dst = metadata_dst_alloc(md_size, METADATA_IP_TUNNEL, GFP_ATOMIC);
145 	if (!tun_dst)
146 		return NULL;
147 
148 	tun_dst->u.tun_info.options_len = 0;
149 	tun_dst->u.tun_info.mode = 0;
150 	return tun_dst;
151 }
152 
tun_dst_unclone(struct sk_buff * skb)153 static inline struct metadata_dst *tun_dst_unclone(struct sk_buff *skb)
154 {
155 	struct metadata_dst *md_dst = skb_metadata_dst(skb);
156 	int md_size;
157 	struct metadata_dst *new_md;
158 
159 	if (!md_dst || md_dst->type != METADATA_IP_TUNNEL)
160 		return ERR_PTR(-EINVAL);
161 
162 	md_size = md_dst->u.tun_info.options_len;
163 	new_md = metadata_dst_alloc(md_size, METADATA_IP_TUNNEL, GFP_ATOMIC);
164 	if (!new_md)
165 		return ERR_PTR(-ENOMEM);
166 
167 	memcpy(&new_md->u.tun_info, &md_dst->u.tun_info,
168 	       sizeof(struct ip_tunnel_info) + md_size);
169 #ifdef CONFIG_DST_CACHE
170 	/* Unclone the dst cache if there is one */
171 	if (new_md->u.tun_info.dst_cache.cache) {
172 		int ret;
173 
174 		ret = dst_cache_init(&new_md->u.tun_info.dst_cache, GFP_ATOMIC);
175 		if (ret) {
176 			metadata_dst_free(new_md);
177 			return ERR_PTR(ret);
178 		}
179 	}
180 #endif
181 
182 	skb_dst_drop(skb);
183 	skb_dst_set(skb, &new_md->dst);
184 	return new_md;
185 }
186 
skb_tunnel_info_unclone(struct sk_buff * skb)187 static inline struct ip_tunnel_info *skb_tunnel_info_unclone(struct sk_buff *skb)
188 {
189 	struct metadata_dst *dst;
190 
191 	dst = tun_dst_unclone(skb);
192 	if (IS_ERR(dst))
193 		return NULL;
194 
195 	return &dst->u.tun_info;
196 }
197 
__ip_tun_set_dst(__be32 saddr,__be32 daddr,__u8 tos,__u8 ttl,__be16 tp_dst,const unsigned long * flags,__be64 tunnel_id,int md_size)198 static inline struct metadata_dst *__ip_tun_set_dst(__be32 saddr,
199 						    __be32 daddr,
200 						    __u8 tos, __u8 ttl,
201 						    __be16 tp_dst,
202 						    const unsigned long *flags,
203 						    __be64 tunnel_id,
204 						    int md_size)
205 {
206 	struct metadata_dst *tun_dst;
207 
208 	tun_dst = tun_rx_dst(md_size);
209 	if (!tun_dst)
210 		return NULL;
211 
212 	ip_tunnel_key_init(&tun_dst->u.tun_info.key,
213 			   saddr, daddr, tos, ttl,
214 			   0, 0, tp_dst, tunnel_id, flags);
215 	return tun_dst;
216 }
217 
ip_tun_rx_dst(struct sk_buff * skb,const unsigned long * flags,__be64 tunnel_id,int md_size)218 static inline struct metadata_dst *ip_tun_rx_dst(struct sk_buff *skb,
219 						 const unsigned long *flags,
220 						 __be64 tunnel_id,
221 						 int md_size)
222 {
223 	const struct iphdr *iph = ip_hdr(skb);
224 	struct metadata_dst *tun_dst;
225 
226 	tun_dst = __ip_tun_set_dst(iph->saddr, iph->daddr, iph->tos, iph->ttl,
227 				   0, flags, tunnel_id, md_size);
228 
229 	if (tun_dst && (iph->frag_off & htons(IP_DF)))
230 		__set_bit(IP_TUNNEL_DONT_FRAGMENT_BIT,
231 			  tun_dst->u.tun_info.key.tun_flags);
232 	return tun_dst;
233 }
234 
__ipv6_tun_set_dst(const struct in6_addr * saddr,const struct in6_addr * daddr,__u8 tos,__u8 ttl,__be16 tp_dst,__be32 label,const unsigned long * flags,__be64 tunnel_id,int md_size)235 static inline struct metadata_dst *__ipv6_tun_set_dst(const struct in6_addr *saddr,
236 						      const struct in6_addr *daddr,
237 						      __u8 tos, __u8 ttl,
238 						      __be16 tp_dst,
239 						      __be32 label,
240 						      const unsigned long *flags,
241 						      __be64 tunnel_id,
242 						      int md_size)
243 {
244 	struct metadata_dst *tun_dst;
245 	struct ip_tunnel_info *info;
246 
247 	tun_dst = tun_rx_dst(md_size);
248 	if (!tun_dst)
249 		return NULL;
250 
251 	info = &tun_dst->u.tun_info;
252 	info->mode = IP_TUNNEL_INFO_IPV6;
253 	ip_tunnel_flags_copy(info->key.tun_flags, flags);
254 	info->key.tun_id = tunnel_id;
255 	info->key.tp_src = 0;
256 	info->key.tp_dst = tp_dst;
257 
258 	info->key.u.ipv6.src = *saddr;
259 	info->key.u.ipv6.dst = *daddr;
260 
261 	info->key.tos = tos;
262 	info->key.ttl = ttl;
263 	info->key.label = label;
264 
265 	return tun_dst;
266 }
267 
ipv6_tun_rx_dst(struct sk_buff * skb,const unsigned long * flags,__be64 tunnel_id,int md_size)268 static inline struct metadata_dst *ipv6_tun_rx_dst(struct sk_buff *skb,
269 						   const unsigned long *flags,
270 						   __be64 tunnel_id,
271 						   int md_size)
272 {
273 	const struct ipv6hdr *ip6h = ipv6_hdr(skb);
274 
275 	return __ipv6_tun_set_dst(&ip6h->saddr, &ip6h->daddr,
276 				  ipv6_get_dsfield(ip6h), ip6h->hop_limit,
277 				  0, ip6_flowlabel(ip6h), flags, tunnel_id,
278 				  md_size);
279 }
280 #endif /* __NET_DST_METADATA_H */
281