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