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	unsafe_memcpy(&new_md->u.tun_info, &md_dst->u.tun_info,
167		      sizeof(struct ip_tunnel_info) + md_size,
168		      /* metadata_dst_alloc() reserves room (md_size bytes) for
169		       * options right after the ip_tunnel_info struct.
170		       */);
171#ifdef CONFIG_DST_CACHE
172	/* Unclone the dst cache if there is one */
173	if (new_md->u.tun_info.dst_cache.cache) {
174		int ret;
175
176		ret = dst_cache_init(&new_md->u.tun_info.dst_cache, GFP_ATOMIC);
177		if (ret) {
178			metadata_dst_free(new_md);
179			return ERR_PTR(ret);
180		}
181	}
182#endif
183
184	skb_dst_drop(skb);
185	skb_dst_set(skb, &new_md->dst);
186	return new_md;
187}
188
189static inline struct ip_tunnel_info *skb_tunnel_info_unclone(struct sk_buff *skb)
190{
191	struct metadata_dst *dst;
192
193	dst = tun_dst_unclone(skb);
194	if (IS_ERR(dst))
195		return NULL;
196
197	return &dst->u.tun_info;
198}
199
200static inline struct metadata_dst *__ip_tun_set_dst(__be32 saddr,
201						    __be32 daddr,
202						    __u8 tos, __u8 ttl,
203						    __be16 tp_dst,
204						    const unsigned long *flags,
205						    __be64 tunnel_id,
206						    int md_size)
207{
208	struct metadata_dst *tun_dst;
209
210	tun_dst = tun_rx_dst(md_size);
211	if (!tun_dst)
212		return NULL;
213
214	ip_tunnel_key_init(&tun_dst->u.tun_info.key,
215			   saddr, daddr, tos, ttl,
216			   0, 0, tp_dst, tunnel_id, flags);
217	return tun_dst;
218}
219
220static inline struct metadata_dst *ip_tun_rx_dst(struct sk_buff *skb,
221						 const unsigned long *flags,
222						 __be64 tunnel_id,
223						 int md_size)
224{
225	const struct iphdr *iph = ip_hdr(skb);
226
227	return __ip_tun_set_dst(iph->saddr, iph->daddr, iph->tos, iph->ttl,
228				0, flags, tunnel_id, md_size);
229}
230
231static inline struct metadata_dst *__ipv6_tun_set_dst(const struct in6_addr *saddr,
232						      const struct in6_addr *daddr,
233						      __u8 tos, __u8 ttl,
234						      __be16 tp_dst,
235						      __be32 label,
236						      const unsigned long *flags,
237						      __be64 tunnel_id,
238						      int md_size)
239{
240	struct metadata_dst *tun_dst;
241	struct ip_tunnel_info *info;
242
243	tun_dst = tun_rx_dst(md_size);
244	if (!tun_dst)
245		return NULL;
246
247	info = &tun_dst->u.tun_info;
248	info->mode = IP_TUNNEL_INFO_IPV6;
249	ip_tunnel_flags_copy(info->key.tun_flags, flags);
250	info->key.tun_id = tunnel_id;
251	info->key.tp_src = 0;
252	info->key.tp_dst = tp_dst;
253
254	info->key.u.ipv6.src = *saddr;
255	info->key.u.ipv6.dst = *daddr;
256
257	info->key.tos = tos;
258	info->key.ttl = ttl;
259	info->key.label = label;
260
261	return tun_dst;
262}
263
264static inline struct metadata_dst *ipv6_tun_rx_dst(struct sk_buff *skb,
265						   const unsigned long *flags,
266						   __be64 tunnel_id,
267						   int md_size)
268{
269	const struct ipv6hdr *ip6h = ipv6_hdr(skb);
270
271	return __ipv6_tun_set_dst(&ip6h->saddr, &ip6h->daddr,
272				  ipv6_get_dsfield(ip6h), ip6h->hop_limit,
273				  0, ip6_flowlabel(ip6h), flags, tunnel_id,
274				  md_size);
275}
276#endif /* __NET_DST_METADATA_H */