net/xfrm/xfrm_inout.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #include <linux/ipv6.h>
   3 #include <net/dsfield.h>
   4 #include <net/xfrm.h>
   5
   6 #ifndef XFRM_INOUT_H
   7 #define XFRM_INOUT_H 1
   8
   9 static inline void xfrm4_extract_header(struct sk_buff *skb)
  10 {
  11         const struct iphdr *iph = ip_hdr(skb);
  12
  13         XFRM_MODE_SKB_CB(skb)->ihl = sizeof(*iph);
  14         XFRM_MODE_SKB_CB(skb)->id = iph->id;
  15         XFRM_MODE_SKB_CB(skb)->frag_off = iph->frag_off;
  16         XFRM_MODE_SKB_CB(skb)->tos = iph->tos;
  17         XFRM_MODE_SKB_CB(skb)->ttl = iph->ttl;
  18         XFRM_MODE_SKB_CB(skb)->optlen = iph->ihl * 4 - sizeof(*iph);
  19         memset(XFRM_MODE_SKB_CB(skb)->flow_lbl, 0,
  20                sizeof(XFRM_MODE_SKB_CB(skb)->flow_lbl));
  21 }
  22
  23 static inline void xfrm6_extract_header(struct sk_buff *skb)
  24 {
  25 #if IS_ENABLED(CONFIG_IPV6)
  26         struct ipv6hdr *iph = ipv6_hdr(skb);
  27
  28         XFRM_MODE_SKB_CB(skb)->ihl = sizeof(*iph);
  29         XFRM_MODE_SKB_CB(skb)->id = 0;
  30         XFRM_MODE_SKB_CB(skb)->frag_off = htons(IP_DF);
  31         XFRM_MODE_SKB_CB(skb)->tos = ipv6_get_dsfield(iph);
  32         XFRM_MODE_SKB_CB(skb)->ttl = iph->hop_limit;
  33         XFRM_MODE_SKB_CB(skb)->optlen = 0;
  34         memcpy(XFRM_MODE_SKB_CB(skb)->flow_lbl, iph->flow_lbl,
  35                sizeof(XFRM_MODE_SKB_CB(skb)->flow_lbl));
  36 #else
  37         WARN_ON_ONCE(1);
  38 #endif
  39 }
  40
  41 static inline void xfrm6_beet_make_header(struct sk_buff *skb)
  42 {
  43         struct ipv6hdr *iph = ipv6_hdr(skb);
  44
  45         iph->version = 6;
  46
  47         memcpy(iph->flow_lbl, XFRM_MODE_SKB_CB(skb)->flow_lbl,
  48                sizeof(iph->flow_lbl));
  49         iph->nexthdr = XFRM_MODE_SKB_CB(skb)->protocol;
  50
  51         ipv6_change_dsfield(iph, 0, XFRM_MODE_SKB_CB(skb)->tos);
  52         iph->hop_limit = XFRM_MODE_SKB_CB(skb)->ttl;
  53 }
  54
  55 static inline void xfrm4_beet_make_header(struct sk_buff *skb)
  56 {
  57         struct iphdr *iph = ip_hdr(skb);
  58
  59         iph->ihl = 5;
  60         iph->version = 4;
  61
  62         iph->protocol = XFRM_MODE_SKB_CB(skb)->protocol;
  63         iph->tos = XFRM_MODE_SKB_CB(skb)->tos;
  64
  65         iph->id = XFRM_MODE_SKB_CB(skb)->id;
  66         iph->frag_off = XFRM_MODE_SKB_CB(skb)->frag_off;
  67         iph->ttl = XFRM_MODE_SKB_CB(skb)->ttl;
  68 }
  69
  70 #endif