net/mpls/internal.h

   1 #ifndef MPLS_INTERNAL_H
   2 #define MPLS_INTERNAL_H
   3
   4 #define LABEL_IPV4_EXPLICIT_NULL        0 /* RFC3032 */
   5 #define LABEL_ROUTER_ALERT_LABEL        1 /* RFC3032 */
   6 #define LABEL_IPV6_EXPLICIT_NULL        2 /* RFC3032 */
   7 #define LABEL_IMPLICIT_NULL             3 /* RFC3032 */
   8 #define LABEL_ENTROPY_INDICATOR         7 /* RFC6790 */
   9 #define LABEL_GAL                       13 /* RFC5586 */
  10 #define LABEL_OAM_ALERT                 14 /* RFC3429 */
  11 #define LABEL_EXTENSION                 15 /* RFC7274 */
  12
  13
  14 struct mpls_shim_hdr {
  15         __be32 label_stack_entry;
  16 };
  17
  18 struct mpls_entry_decoded {
  19         u32 label;
  20         u8 ttl;
  21         u8 tc;
  22         u8 bos;
  23 };
  24
  25 struct sk_buff;
  26
  27 static inline struct mpls_shim_hdr *mpls_hdr(const struct sk_buff *skb)
  28 {
  29         return (struct mpls_shim_hdr *)skb_network_header(skb);
  30 }
  31
  32 static inline struct mpls_shim_hdr mpls_entry_encode(u32 label, unsigned ttl, unsigned tc, bool bos)
  33 {
  34         struct mpls_shim_hdr result;
  35         result.label_stack_entry =
  36                 cpu_to_be32((label << MPLS_LS_LABEL_SHIFT) |
  37                             (tc << MPLS_LS_TC_SHIFT) |
  38                             (bos ? (1 << MPLS_LS_S_SHIFT) : 0) |
  39                             (ttl << MPLS_LS_TTL_SHIFT));
  40         return result;
  41 }
  42
  43 static inline struct mpls_entry_decoded mpls_entry_decode(struct mpls_shim_hdr *hdr)
  44 {
  45         struct mpls_entry_decoded result;
  46         unsigned entry = be32_to_cpu(hdr->label_stack_entry);
  47
  48         result.label = (entry & MPLS_LS_LABEL_MASK) >> MPLS_LS_LABEL_SHIFT;
  49         result.ttl = (entry & MPLS_LS_TTL_MASK) >> MPLS_LS_TTL_SHIFT;
  50         result.tc =  (entry & MPLS_LS_TC_MASK) >> MPLS_LS_TC_SHIFT;
  51         result.bos = (entry & MPLS_LS_S_MASK) >> MPLS_LS_S_SHIFT;
  52
  53         return result;
  54 }
  55
  56 int nla_put_labels(struct sk_buff *skb, int attrtype,  u8 labels, const u32 label[]);
  57 int nla_get_labels(const struct nlattr *nla, u32 max_labels, u32 *labels, u32 label[]);
  58
  59 #endif /* MPLS_INTERNAL_H */