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 u32 nh_label[MAX_NEW_LABELS]; 45 u8 nh_labels; 46 u8 nh_via_alen; 47 u8 nh_via_table; 48 }; 49 50 /* The route, nexthops and vias are stored together in the same memory 51 * block: 52 * 53 * +----------------------+ 54 * | mpls_route | 55 * +----------------------+ 56 * | mpls_nh 0 | 57 * +----------------------+ 58 * | ... | 59 * +----------------------+ 60 * | mpls_nh n-1 | 61 * +----------------------+ 62 * | alignment padding | 63 * +----------------------+ 64 * | via[rt_max_alen] 0 | 65 * +----------------------+ 66 * | ... | 67 * +----------------------+ 68 * | via[rt_max_alen] n-1 | 69 * +----------------------+ 70 */ 71 struct mpls_route { /* next hop label forwarding entry */ 72 struct rcu_head rt_rcu; 73 u8 rt_protocol; 74 u8 rt_payload_type; 75 u8 rt_max_alen; 76 unsigned int rt_nhn; 77 struct mpls_nh rt_nh[0]; 78 }; 79 80 #define for_nexthops(rt) { \ 81 int nhsel; struct mpls_nh *nh; \ 82 for (nhsel = 0, nh = (rt)->rt_nh; \ 83 nhsel < (rt)->rt_nhn; \ 84 nh++, nhsel++) 85 86 #define change_nexthops(rt) { \ 87 int nhsel; struct mpls_nh *nh; \ 88 for (nhsel = 0, nh = (struct mpls_nh *)((rt)->rt_nh); \ 89 nhsel < (rt)->rt_nhn; \ 90 nh++, nhsel++) 91 92 #define endfor_nexthops(rt) } 93 94 static inline struct mpls_shim_hdr *mpls_hdr(const struct sk_buff *skb) 95 { 96 return (struct mpls_shim_hdr *)skb_network_header(skb); 97 } 98 99 static inline struct mpls_shim_hdr mpls_entry_encode(u32 label, unsigned ttl, unsigned tc, bool bos) 100 { 101 struct mpls_shim_hdr result; 102 result.label_stack_entry = 103 cpu_to_be32((label << MPLS_LS_LABEL_SHIFT) | 104 (tc << MPLS_LS_TC_SHIFT) | 105 (bos ? (1 << MPLS_LS_S_SHIFT) : 0) | 106 (ttl << MPLS_LS_TTL_SHIFT)); 107 return result; 108 } 109 110 static inline struct mpls_entry_decoded mpls_entry_decode(struct mpls_shim_hdr *hdr) 111 { 112 struct mpls_entry_decoded result; 113 unsigned entry = be32_to_cpu(hdr->label_stack_entry); 114 115 result.label = (entry & MPLS_LS_LABEL_MASK) >> MPLS_LS_LABEL_SHIFT; 116 result.ttl = (entry & MPLS_LS_TTL_MASK) >> MPLS_LS_TTL_SHIFT; 117 result.tc = (entry & MPLS_LS_TC_MASK) >> MPLS_LS_TC_SHIFT; 118 result.bos = (entry & MPLS_LS_S_MASK) >> MPLS_LS_S_SHIFT; 119 120 return result; 121 } 122 123 int nla_put_labels(struct sk_buff *skb, int attrtype, u8 labels, 124 const u32 label[]); 125 int nla_get_labels(const struct nlattr *nla, u32 max_labels, u8 *labels, 126 u32 label[]); 127 int nla_get_via(const struct nlattr *nla, u8 *via_alen, u8 *via_table, 128 u8 via[]); 129 bool mpls_output_possible(const struct net_device *dev); 130 unsigned int mpls_dev_mtu(const struct net_device *dev); 131 bool mpls_pkt_too_big(const struct sk_buff *skb, unsigned int mtu); 132 133 #endif /* MPLS_INTERNAL_H */ 134