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 #define LABEL_NOT_SPECIFIED (1 << 20) 25 #define MAX_NEW_LABELS 2 26 27 /* This maximum ha length copied from the definition of struct neighbour */ 28 #define VIA_ALEN_ALIGN sizeof(unsigned long) 29 #define MAX_VIA_ALEN (ALIGN(MAX_ADDR_LEN, VIA_ALEN_ALIGN)) 30 31 enum mpls_payload_type { 32 MPT_UNSPEC, /* IPv4 or IPv6 */ 33 MPT_IPV4 = 4, 34 MPT_IPV6 = 6, 35 36 /* Other types not implemented: 37 * - Pseudo-wire with or without control word (RFC4385) 38 * - GAL (RFC5586) 39 */ 40 }; 41 42 struct mpls_nh { /* next hop label forwarding entry */ 43 struct net_device __rcu *nh_dev; 44 unsigned int nh_flags; 45 u32 nh_label[MAX_NEW_LABELS]; 46 u8 nh_labels; 47 u8 nh_via_alen; 48 u8 nh_via_table; 49 }; 50 51 /* The route, nexthops and vias are stored together in the same memory 52 * block: 53 * 54 * +----------------------+ 55 * | mpls_route | 56 * +----------------------+ 57 * | mpls_nh 0 | 58 * +----------------------+ 59 * | ... | 60 * +----------------------+ 61 * | mpls_nh n-1 | 62 * +----------------------+ 63 * | alignment padding | 64 * +----------------------+ 65 * | via[rt_max_alen] 0 | 66 * +----------------------+ 67 * | ... | 68 * +----------------------+ 69 * | via[rt_max_alen] n-1 | 70 * +----------------------+ 71 */ 72 struct mpls_route { /* next hop label forwarding entry */ 73 struct rcu_head rt_rcu; 74 u8 rt_protocol; 75 u8 rt_payload_type; 76 u8 rt_max_alen; 77 unsigned int rt_nhn; 78 unsigned int rt_nhn_alive; 79 struct mpls_nh rt_nh[0]; 80 }; 81 82 #define for_nexthops(rt) { \ 83 int nhsel; struct mpls_nh *nh; \ 84 for (nhsel = 0, nh = (rt)->rt_nh; \ 85 nhsel < (rt)->rt_nhn; \ 86 nh++, nhsel++) 87 88 #define change_nexthops(rt) { \ 89 int nhsel; struct mpls_nh *nh; \ 90 for (nhsel = 0, nh = (struct mpls_nh *)((rt)->rt_nh); \ 91 nhsel < (rt)->rt_nhn; \ 92 nh++, nhsel++) 93 94 #define endfor_nexthops(rt) } 95 96 static inline struct mpls_shim_hdr *mpls_hdr(const struct sk_buff *skb) 97 { 98 return (struct mpls_shim_hdr *)skb_network_header(skb); 99 } 100 101 static inline struct mpls_shim_hdr mpls_entry_encode(u32 label, unsigned ttl, unsigned tc, bool bos) 102 { 103 struct mpls_shim_hdr result; 104 result.label_stack_entry = 105 cpu_to_be32((label << MPLS_LS_LABEL_SHIFT) | 106 (tc << MPLS_LS_TC_SHIFT) | 107 (bos ? (1 << MPLS_LS_S_SHIFT) : 0) | 108 (ttl << MPLS_LS_TTL_SHIFT)); 109 return result; 110 } 111 112 static inline struct mpls_entry_decoded mpls_entry_decode(struct mpls_shim_hdr *hdr) 113 { 114 struct mpls_entry_decoded result; 115 unsigned entry = be32_to_cpu(hdr->label_stack_entry); 116 117 result.label = (entry & MPLS_LS_LABEL_MASK) >> MPLS_LS_LABEL_SHIFT; 118 result.ttl = (entry & MPLS_LS_TTL_MASK) >> MPLS_LS_TTL_SHIFT; 119 result.tc = (entry & MPLS_LS_TC_MASK) >> MPLS_LS_TC_SHIFT; 120 result.bos = (entry & MPLS_LS_S_MASK) >> MPLS_LS_S_SHIFT; 121 122 return result; 123 } 124 125 int nla_put_labels(struct sk_buff *skb, int attrtype, u8 labels, 126 const u32 label[]); 127 int nla_get_labels(const struct nlattr *nla, u32 max_labels, u8 *labels, 128 u32 label[]); 129 int nla_get_via(const struct nlattr *nla, u8 *via_alen, u8 *via_table, 130 u8 via[]); 131 bool mpls_output_possible(const struct net_device *dev); 132 unsigned int mpls_dev_mtu(const struct net_device *dev); 133 bool mpls_pkt_too_big(const struct sk_buff *skb, unsigned int mtu); 134 135 #endif /* MPLS_INTERNAL_H */ 136