xref: /linux/net/mpls/internal.h (revision 3b27d13940c3710a1128527c43719cb0bb05d73b)
1 #ifndef MPLS_INTERNAL_H
2 #define MPLS_INTERNAL_H
3 
4 struct mpls_shim_hdr {
5 	__be32 label_stack_entry;
6 };
7 
8 struct mpls_entry_decoded {
9 	u32 label;
10 	u8 ttl;
11 	u8 tc;
12 	u8 bos;
13 };
14 
15 struct mpls_dev {
16 	int			input_enabled;
17 
18 	struct ctl_table_header *sysctl;
19 	struct rcu_head		rcu;
20 };
21 
22 struct sk_buff;
23 
24 static inline struct mpls_shim_hdr *mpls_hdr(const struct sk_buff *skb)
25 {
26 	return (struct mpls_shim_hdr *)skb_network_header(skb);
27 }
28 
29 static inline struct mpls_shim_hdr mpls_entry_encode(u32 label, unsigned ttl, unsigned tc, bool bos)
30 {
31 	struct mpls_shim_hdr result;
32 	result.label_stack_entry =
33 		cpu_to_be32((label << MPLS_LS_LABEL_SHIFT) |
34 			    (tc << MPLS_LS_TC_SHIFT) |
35 			    (bos ? (1 << MPLS_LS_S_SHIFT) : 0) |
36 			    (ttl << MPLS_LS_TTL_SHIFT));
37 	return result;
38 }
39 
40 static inline struct mpls_entry_decoded mpls_entry_decode(struct mpls_shim_hdr *hdr)
41 {
42 	struct mpls_entry_decoded result;
43 	unsigned entry = be32_to_cpu(hdr->label_stack_entry);
44 
45 	result.label = (entry & MPLS_LS_LABEL_MASK) >> MPLS_LS_LABEL_SHIFT;
46 	result.ttl = (entry & MPLS_LS_TTL_MASK) >> MPLS_LS_TTL_SHIFT;
47 	result.tc =  (entry & MPLS_LS_TC_MASK) >> MPLS_LS_TC_SHIFT;
48 	result.bos = (entry & MPLS_LS_S_MASK) >> MPLS_LS_S_SHIFT;
49 
50 	return result;
51 }
52 
53 int nla_put_labels(struct sk_buff *skb, int attrtype,  u8 labels, const u32 label[]);
54 int nla_get_labels(const struct nlattr *nla, u32 max_labels, u32 *labels, u32 label[]);
55 
56 #endif /* MPLS_INTERNAL_H */
57