1 #ifndef MPLS_INTERNAL_H 2 #define MPLS_INTERNAL_H 3 #include <net/mpls.h> 4 5 /* put a reasonable limit on the number of labels 6 * we will accept from userspace 7 */ 8 #define MAX_NEW_LABELS 30 9 10 struct mpls_entry_decoded { 11 u32 label; 12 u8 ttl; 13 u8 tc; 14 u8 bos; 15 }; 16 17 struct mpls_pcpu_stats { 18 struct mpls_link_stats stats; 19 struct u64_stats_sync syncp; 20 }; 21 22 struct mpls_dev { 23 int input_enabled; 24 struct net_device *dev; 25 struct mpls_pcpu_stats __percpu *stats; 26 27 struct ctl_table_header *sysctl; 28 struct rcu_head rcu; 29 }; 30 31 #if BITS_PER_LONG == 32 32 33 #define MPLS_INC_STATS_LEN(mdev, len, pkts_field, bytes_field) \ 34 do { \ 35 __typeof__(*(mdev)->stats) *ptr = \ 36 raw_cpu_ptr((mdev)->stats); \ 37 local_bh_disable(); \ 38 u64_stats_update_begin(&ptr->syncp); \ 39 ptr->stats.pkts_field++; \ 40 ptr->stats.bytes_field += (len); \ 41 u64_stats_update_end(&ptr->syncp); \ 42 local_bh_enable(); \ 43 } while (0) 44 45 #define MPLS_INC_STATS(mdev, field) \ 46 do { \ 47 __typeof__(*(mdev)->stats) *ptr = \ 48 raw_cpu_ptr((mdev)->stats); \ 49 local_bh_disable(); \ 50 u64_stats_update_begin(&ptr->syncp); \ 51 ptr->stats.field++; \ 52 u64_stats_update_end(&ptr->syncp); \ 53 local_bh_enable(); \ 54 } while (0) 55 56 #else 57 58 #define MPLS_INC_STATS_LEN(mdev, len, pkts_field, bytes_field) \ 59 do { \ 60 this_cpu_inc((mdev)->stats->stats.pkts_field); \ 61 this_cpu_add((mdev)->stats->stats.bytes_field, (len)); \ 62 } while (0) 63 64 #define MPLS_INC_STATS(mdev, field) \ 65 this_cpu_inc((mdev)->stats->stats.field) 66 67 #endif 68 69 struct sk_buff; 70 71 #define LABEL_NOT_SPECIFIED (1 << 20) 72 73 /* This maximum ha length copied from the definition of struct neighbour */ 74 #define VIA_ALEN_ALIGN sizeof(unsigned long) 75 #define MAX_VIA_ALEN (ALIGN(MAX_ADDR_LEN, VIA_ALEN_ALIGN)) 76 77 enum mpls_payload_type { 78 MPT_UNSPEC, /* IPv4 or IPv6 */ 79 MPT_IPV4 = 4, 80 MPT_IPV6 = 6, 81 82 /* Other types not implemented: 83 * - Pseudo-wire with or without control word (RFC4385) 84 * - GAL (RFC5586) 85 */ 86 }; 87 88 struct mpls_nh { /* next hop label forwarding entry */ 89 struct net_device __rcu *nh_dev; 90 91 /* nh_flags is accessed under RCU in the packet path; it is 92 * modified handling netdev events with rtnl lock held 93 */ 94 unsigned int nh_flags; 95 u8 nh_labels; 96 u8 nh_via_alen; 97 u8 nh_via_table; 98 u8 nh_reserved1; 99 100 u32 nh_label[0]; 101 }; 102 103 /* offset of via from beginning of mpls_nh */ 104 #define MPLS_NH_VIA_OFF(num_labels) \ 105 ALIGN(sizeof(struct mpls_nh) + (num_labels) * sizeof(u32), \ 106 VIA_ALEN_ALIGN) 107 108 /* all nexthops within a route have the same size based on the 109 * max number of labels and max via length across all nexthops 110 */ 111 #define MPLS_NH_SIZE(num_labels, max_via_alen) \ 112 (MPLS_NH_VIA_OFF((num_labels)) + \ 113 ALIGN((max_via_alen), VIA_ALEN_ALIGN)) 114 115 enum mpls_ttl_propagation { 116 MPLS_TTL_PROP_DEFAULT, 117 MPLS_TTL_PROP_ENABLED, 118 MPLS_TTL_PROP_DISABLED, 119 }; 120 121 /* The route, nexthops and vias are stored together in the same memory 122 * block: 123 * 124 * +----------------------+ 125 * | mpls_route | 126 * +----------------------+ 127 * | mpls_nh 0 | 128 * +----------------------+ 129 * | alignment padding | 4 bytes for odd number of labels 130 * +----------------------+ 131 * | via[rt_max_alen] 0 | 132 * +----------------------+ 133 * | alignment padding | via's aligned on sizeof(unsigned long) 134 * +----------------------+ 135 * | ... | 136 * +----------------------+ 137 * | mpls_nh n-1 | 138 * +----------------------+ 139 * | via[rt_max_alen] n-1 | 140 * +----------------------+ 141 */ 142 struct mpls_route { /* next hop label forwarding entry */ 143 struct rcu_head rt_rcu; 144 u8 rt_protocol; 145 u8 rt_payload_type; 146 u8 rt_max_alen; 147 u8 rt_ttl_propagate; 148 u8 rt_nhn; 149 /* rt_nhn_alive is accessed under RCU in the packet path; it 150 * is modified handling netdev events with rtnl lock held 151 */ 152 u8 rt_nhn_alive; 153 u8 rt_nh_size; 154 u8 rt_via_offset; 155 u8 rt_reserved1; 156 struct mpls_nh rt_nh[0]; 157 }; 158 159 #define for_nexthops(rt) { \ 160 int nhsel; struct mpls_nh *nh; u8 *__nh; \ 161 for (nhsel = 0, nh = (rt)->rt_nh, __nh = (u8 *)((rt)->rt_nh); \ 162 nhsel < (rt)->rt_nhn; \ 163 __nh += rt->rt_nh_size, nh = (struct mpls_nh *)__nh, nhsel++) 164 165 #define change_nexthops(rt) { \ 166 int nhsel; struct mpls_nh *nh; u8 *__nh; \ 167 for (nhsel = 0, nh = (struct mpls_nh *)((rt)->rt_nh), \ 168 __nh = (u8 *)((rt)->rt_nh); \ 169 nhsel < (rt)->rt_nhn; \ 170 __nh += rt->rt_nh_size, nh = (struct mpls_nh *)__nh, nhsel++) 171 172 #define endfor_nexthops(rt) } 173 174 static inline struct mpls_shim_hdr mpls_entry_encode(u32 label, unsigned ttl, unsigned tc, bool bos) 175 { 176 struct mpls_shim_hdr result; 177 result.label_stack_entry = 178 cpu_to_be32((label << MPLS_LS_LABEL_SHIFT) | 179 (tc << MPLS_LS_TC_SHIFT) | 180 (bos ? (1 << MPLS_LS_S_SHIFT) : 0) | 181 (ttl << MPLS_LS_TTL_SHIFT)); 182 return result; 183 } 184 185 static inline struct mpls_entry_decoded mpls_entry_decode(struct mpls_shim_hdr *hdr) 186 { 187 struct mpls_entry_decoded result; 188 unsigned entry = be32_to_cpu(hdr->label_stack_entry); 189 190 result.label = (entry & MPLS_LS_LABEL_MASK) >> MPLS_LS_LABEL_SHIFT; 191 result.ttl = (entry & MPLS_LS_TTL_MASK) >> MPLS_LS_TTL_SHIFT; 192 result.tc = (entry & MPLS_LS_TC_MASK) >> MPLS_LS_TC_SHIFT; 193 result.bos = (entry & MPLS_LS_S_MASK) >> MPLS_LS_S_SHIFT; 194 195 return result; 196 } 197 198 static inline struct mpls_dev *mpls_dev_get(const struct net_device *dev) 199 { 200 return rcu_dereference_rtnl(dev->mpls_ptr); 201 } 202 203 int nla_put_labels(struct sk_buff *skb, int attrtype, u8 labels, 204 const u32 label[]); 205 int nla_get_labels(const struct nlattr *nla, u8 max_labels, u8 *labels, 206 u32 label[], struct netlink_ext_ack *extack); 207 bool mpls_output_possible(const struct net_device *dev); 208 unsigned int mpls_dev_mtu(const struct net_device *dev); 209 bool mpls_pkt_too_big(const struct sk_buff *skb, unsigned int mtu); 210 void mpls_stats_inc_outucastpkts(struct net_device *dev, 211 const struct sk_buff *skb); 212 213 #endif /* MPLS_INTERNAL_H */ 214