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	skb_dst_drop(skb);
127	dst_hold(&new_md->dst);
128	skb_dst_set(skb, &new_md->dst);
129	return new_md;
130}
131
132static inline struct ip_tunnel_info *skb_tunnel_info_unclone(struct sk_buff *skb)
133{
134	struct metadata_dst *dst;
135
136	dst = tun_dst_unclone(skb);
137	if (IS_ERR(dst))
138		return NULL;
139
140	return &dst->u.tun_info;
141}
142
143static inline struct metadata_dst *__ip_tun_set_dst(__be32 saddr,
144						    __be32 daddr,
145						    __u8 tos, __u8 ttl,
146						    __be16 tp_dst,
147						    __be16 flags,
148						    __be64 tunnel_id,
149						    int md_size)
150{
151	struct metadata_dst *tun_dst;
152
153	tun_dst = tun_rx_dst(md_size);
154	if (!tun_dst)
155		return NULL;
156
157	ip_tunnel_key_init(&tun_dst->u.tun_info.key,
158			   saddr, daddr, tos, ttl,
159			   0, 0, tp_dst, tunnel_id, flags);
160	return tun_dst;
161}
162
163static inline struct metadata_dst *ip_tun_rx_dst(struct sk_buff *skb,
164						 __be16 flags,
165						 __be64 tunnel_id,
166						 int md_size)
167{
168	const struct iphdr *iph = ip_hdr(skb);
169
170	return __ip_tun_set_dst(iph->saddr, iph->daddr, iph->tos, iph->ttl,
171				0, flags, tunnel_id, md_size);
172}
173
174static inline struct metadata_dst *__ipv6_tun_set_dst(const struct in6_addr *saddr,
175						      const struct in6_addr *daddr,
176						      __u8 tos, __u8 ttl,
177						      __be16 tp_dst,
178						      __be32 label,
179						      __be16 flags,
180						      __be64 tunnel_id,
181						      int md_size)
182{
183	struct metadata_dst *tun_dst;
184	struct ip_tunnel_info *info;
185
186	tun_dst = tun_rx_dst(md_size);
187	if (!tun_dst)
188		return NULL;
189
190	info = &tun_dst->u.tun_info;
191	info->mode = IP_TUNNEL_INFO_IPV6;
192	info->key.tun_flags = flags;
193	info->key.tun_id = tunnel_id;
194	info->key.tp_src = 0;
195	info->key.tp_dst = tp_dst;
196
197	info->key.u.ipv6.src = *saddr;
198	info->key.u.ipv6.dst = *daddr;
199
200	info->key.tos = tos;
201	info->key.ttl = ttl;
202	info->key.label = label;
203
204	return tun_dst;
205}
206
207static inline struct metadata_dst *ipv6_tun_rx_dst(struct sk_buff *skb,
208						   __be16 flags,
209						   __be64 tunnel_id,
210						   int md_size)
211{
212	const struct ipv6hdr *ip6h = ipv6_hdr(skb);
213
214	return __ipv6_tun_set_dst(&ip6h->saddr, &ip6h->daddr,
215				  ipv6_get_dsfield(ip6h), ip6h->hop_limit,
216				  0, ip6_flowlabel(ip6h), flags, tunnel_id,
217				  md_size);
218}
219#endif /* __NET_DST_METADATA_H */