1 #ifndef __NET_DST_METADATA_H 2 #define __NET_DST_METADATA_H 1 3 4 #include <linux/skbuff.h> 5 #include <net/ip_tunnels.h> 6 #include <net/dst.h> 7 8 struct metadata_dst { 9 struct dst_entry dst; 10 union { 11 struct ip_tunnel_info tun_info; 12 } u; 13 }; 14 15 static inline struct metadata_dst *skb_metadata_dst(struct sk_buff *skb) 16 { 17 struct metadata_dst *md_dst = (struct metadata_dst *) skb_dst(skb); 18 19 if (md_dst && md_dst->dst.flags & DST_METADATA) 20 return md_dst; 21 22 return NULL; 23 } 24 25 static inline struct ip_tunnel_info *skb_tunnel_info(struct sk_buff *skb) 26 { 27 struct metadata_dst *md_dst = skb_metadata_dst(skb); 28 struct dst_entry *dst; 29 30 if (md_dst) 31 return &md_dst->u.tun_info; 32 33 dst = skb_dst(skb); 34 if (dst && dst->lwtstate) 35 return lwt_tun_info(dst->lwtstate); 36 37 return NULL; 38 } 39 40 static inline bool skb_valid_dst(const struct sk_buff *skb) 41 { 42 struct dst_entry *dst = skb_dst(skb); 43 44 return dst && !(dst->flags & DST_METADATA); 45 } 46 47 static inline int skb_metadata_dst_cmp(const struct sk_buff *skb_a, 48 const struct sk_buff *skb_b) 49 { 50 const struct metadata_dst *a, *b; 51 52 if (!(skb_a->_skb_refdst | skb_b->_skb_refdst)) 53 return 0; 54 55 a = (const struct metadata_dst *) skb_dst(skb_a); 56 b = (const struct metadata_dst *) skb_dst(skb_b); 57 58 if (!a != !b || a->u.tun_info.options_len != b->u.tun_info.options_len) 59 return 1; 60 61 return memcmp(&a->u.tun_info, &b->u.tun_info, 62 sizeof(a->u.tun_info) + a->u.tun_info.options_len); 63 } 64 65 void metadata_dst_free(struct metadata_dst *); 66 struct metadata_dst *metadata_dst_alloc(u8 optslen, gfp_t flags); 67 struct metadata_dst __percpu *metadata_dst_alloc_percpu(u8 optslen, gfp_t flags); 68 69 static inline struct metadata_dst *tun_rx_dst(int md_size) 70 { 71 struct metadata_dst *tun_dst; 72 73 tun_dst = metadata_dst_alloc(md_size, GFP_ATOMIC); 74 if (!tun_dst) 75 return NULL; 76 77 tun_dst->u.tun_info.options_len = 0; 78 tun_dst->u.tun_info.mode = 0; 79 return tun_dst; 80 } 81 82 static inline struct metadata_dst *tun_dst_unclone(struct sk_buff *skb) 83 { 84 struct metadata_dst *md_dst = skb_metadata_dst(skb); 85 int md_size; 86 struct metadata_dst *new_md; 87 88 if (!md_dst) 89 return ERR_PTR(-EINVAL); 90 91 md_size = md_dst->u.tun_info.options_len; 92 new_md = metadata_dst_alloc(md_size, GFP_ATOMIC); 93 if (!new_md) 94 return ERR_PTR(-ENOMEM); 95 96 memcpy(&new_md->u.tun_info, &md_dst->u.tun_info, 97 sizeof(struct ip_tunnel_info) + md_size); 98 skb_dst_drop(skb); 99 dst_hold(&new_md->dst); 100 skb_dst_set(skb, &new_md->dst); 101 return new_md; 102 } 103 104 static inline struct ip_tunnel_info *skb_tunnel_info_unclone(struct sk_buff *skb) 105 { 106 struct metadata_dst *dst; 107 108 dst = tun_dst_unclone(skb); 109 if (IS_ERR(dst)) 110 return NULL; 111 112 return &dst->u.tun_info; 113 } 114 115 static inline struct metadata_dst *ip_tun_rx_dst(struct sk_buff *skb, 116 __be16 flags, 117 __be64 tunnel_id, 118 int md_size) 119 { 120 const struct iphdr *iph = ip_hdr(skb); 121 struct metadata_dst *tun_dst; 122 123 tun_dst = tun_rx_dst(md_size); 124 if (!tun_dst) 125 return NULL; 126 127 ip_tunnel_key_init(&tun_dst->u.tun_info.key, 128 iph->saddr, iph->daddr, iph->tos, iph->ttl, 129 0, 0, 0, tunnel_id, flags); 130 return tun_dst; 131 } 132 133 static inline struct metadata_dst *ipv6_tun_rx_dst(struct sk_buff *skb, 134 __be16 flags, 135 __be64 tunnel_id, 136 int md_size) 137 { 138 const struct ipv6hdr *ip6h = ipv6_hdr(skb); 139 struct metadata_dst *tun_dst; 140 struct ip_tunnel_info *info; 141 142 tun_dst = tun_rx_dst(md_size); 143 if (!tun_dst) 144 return NULL; 145 146 info = &tun_dst->u.tun_info; 147 info->mode = IP_TUNNEL_INFO_IPV6; 148 info->key.tun_flags = flags; 149 info->key.tun_id = tunnel_id; 150 info->key.tp_src = 0; 151 info->key.tp_dst = 0; 152 153 info->key.u.ipv6.src = ip6h->saddr; 154 info->key.u.ipv6.dst = ip6h->daddr; 155 156 info->key.tos = ipv6_get_dsfield(ip6h); 157 info->key.ttl = ip6h->hop_limit; 158 info->key.label = ip6_flowlabel(ip6h); 159 160 return tun_dst; 161 } 162 163 #endif /* __NET_DST_METADATA_H */ 164