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 struct metadata_dst *metadata_dst_alloc(u8 optslen, gfp_t flags); 66 struct metadata_dst __percpu *metadata_dst_alloc_percpu(u8 optslen, gfp_t flags); 67 68 static inline struct metadata_dst *tun_rx_dst(int md_size) 69 { 70 struct metadata_dst *tun_dst; 71 72 tun_dst = metadata_dst_alloc(md_size, GFP_ATOMIC); 73 if (!tun_dst) 74 return NULL; 75 76 tun_dst->u.tun_info.options_len = 0; 77 tun_dst->u.tun_info.mode = 0; 78 return tun_dst; 79 } 80 81 static inline struct metadata_dst *tun_dst_unclone(struct sk_buff *skb) 82 { 83 struct metadata_dst *md_dst = skb_metadata_dst(skb); 84 int md_size; 85 struct metadata_dst *new_md; 86 87 if (!md_dst) 88 return ERR_PTR(-EINVAL); 89 90 md_size = md_dst->u.tun_info.options_len; 91 new_md = metadata_dst_alloc(md_size, GFP_ATOMIC); 92 if (!new_md) 93 return ERR_PTR(-ENOMEM); 94 95 memcpy(&new_md->u.tun_info, &md_dst->u.tun_info, 96 sizeof(struct ip_tunnel_info) + md_size); 97 skb_dst_drop(skb); 98 dst_hold(&new_md->dst); 99 skb_dst_set(skb, &new_md->dst); 100 return new_md; 101 } 102 103 static inline struct ip_tunnel_info *skb_tunnel_info_unclone(struct sk_buff *skb) 104 { 105 struct metadata_dst *dst; 106 107 dst = tun_dst_unclone(skb); 108 if (IS_ERR(dst)) 109 return NULL; 110 111 return &dst->u.tun_info; 112 } 113 114 static inline struct metadata_dst *ip_tun_rx_dst(struct sk_buff *skb, 115 __be16 flags, 116 __be64 tunnel_id, 117 int md_size) 118 { 119 const struct iphdr *iph = ip_hdr(skb); 120 struct metadata_dst *tun_dst; 121 122 tun_dst = tun_rx_dst(md_size); 123 if (!tun_dst) 124 return NULL; 125 126 ip_tunnel_key_init(&tun_dst->u.tun_info.key, 127 iph->saddr, iph->daddr, iph->tos, iph->ttl, 128 0, 0, tunnel_id, flags); 129 return tun_dst; 130 } 131 132 static inline struct metadata_dst *ipv6_tun_rx_dst(struct sk_buff *skb, 133 __be16 flags, 134 __be64 tunnel_id, 135 int md_size) 136 { 137 const struct ipv6hdr *ip6h = ipv6_hdr(skb); 138 struct metadata_dst *tun_dst; 139 struct ip_tunnel_info *info; 140 141 tun_dst = tun_rx_dst(md_size); 142 if (!tun_dst) 143 return NULL; 144 145 info = &tun_dst->u.tun_info; 146 info->mode = IP_TUNNEL_INFO_IPV6; 147 info->key.tun_flags = flags; 148 info->key.tun_id = tunnel_id; 149 info->key.tp_src = 0; 150 info->key.tp_dst = 0; 151 152 info->key.u.ipv6.src = ip6h->saddr; 153 info->key.u.ipv6.dst = ip6h->daddr; 154 info->key.tos = ipv6_get_dsfield(ip6h); 155 info->key.ttl = ip6h->hop_limit; 156 return tun_dst; 157 } 158 159 #endif /* __NET_DST_METADATA_H */ 160