~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

TOMOYO Linux Cross Reference
Linux/net/ipv4/xfrm4_mode_tunnel.c

Version: ~ [ linux-6.0-rc6 ] ~ [ linux-5.19.10 ] ~ [ linux-5.18.19 ] ~ [ linux-5.17.15 ] ~ [ linux-5.16.20 ] ~ [ linux-5.15.69 ] ~ [ linux-5.14.21 ] ~ [ linux-5.13.19 ] ~ [ linux-5.12.19 ] ~ [ linux-5.11.22 ] ~ [ linux-5.10.144 ] ~ [ linux-5.9.16 ] ~ [ linux-5.8.18 ] ~ [ linux-5.7.19 ] ~ [ linux-5.6.19 ] ~ [ linux-5.5.19 ] ~ [ linux-5.4.214 ] ~ [ linux-5.3.18 ] ~ [ linux-5.2.21 ] ~ [ linux-5.1.21 ] ~ [ linux-5.0.21 ] ~ [ linux-4.20.17 ] ~ [ linux-4.19.259 ] ~ [ linux-4.18.20 ] ~ [ linux-4.17.19 ] ~ [ linux-4.16.18 ] ~ [ linux-4.15.18 ] ~ [ linux-4.14.294 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.329 ] ~ [ linux-4.8.17 ] ~ [ linux-4.7.10 ] ~ [ linux-4.6.7 ] ~ [ linux-4.5.7 ] ~ [ linux-4.4.302 ] ~ [ linux-4.3.6 ] ~ [ linux-4.2.8 ] ~ [ linux-4.1.52 ] ~ [ linux-4.0.9 ] ~ [ linux-3.10.108 ] ~ [ linux-2.6.32.71 ] ~ [ linux-2.6.0 ] ~ [ linux-2.4.37.11 ] ~ [ unix-v6-master ] ~ [ ccs-tools-1.8.9 ] ~ [ policy-sample ] ~
Architecture: ~ [ i386 ] ~ [ alpha ] ~ [ m68k ] ~ [ mips ] ~ [ ppc ] ~ [ sparc ] ~ [ sparc64 ] ~

  1 /*
  2  * xfrm4_mode_tunnel.c - Tunnel mode encapsulation for IPv4.
  3  *
  4  * Copyright (c) 2004-2006 Herbert Xu <herbert@gondor.apana.org.au>
  5  */
  6 
  7 #include <linux/gfp.h>
  8 #include <linux/init.h>
  9 #include <linux/kernel.h>
 10 #include <linux/module.h>
 11 #include <linux/skbuff.h>
 12 #include <linux/stringify.h>
 13 #include <net/dst.h>
 14 #include <net/inet_ecn.h>
 15 #include <net/ip.h>
 16 #include <net/xfrm.h>
 17 
 18 static inline void ipip_ecn_decapsulate(struct sk_buff *skb)
 19 {
 20         struct iphdr *inner_iph = ipip_hdr(skb);
 21 
 22         if (INET_ECN_is_ce(XFRM_MODE_SKB_CB(skb)->tos))
 23                 IP_ECN_set_ce(inner_iph);
 24 }
 25 
 26 /* Add encapsulation header.
 27  *
 28  * The top IP header will be constructed per RFC 2401.
 29  */
 30 static int xfrm4_mode_tunnel_output(struct xfrm_state *x, struct sk_buff *skb)
 31 {
 32         struct dst_entry *dst = skb_dst(skb);
 33         struct iphdr *top_iph;
 34         int flags;
 35 
 36         skb_set_network_header(skb, -x->props.header_len);
 37         skb->mac_header = skb->network_header +
 38                           offsetof(struct iphdr, protocol);
 39         skb->transport_header = skb->network_header + sizeof(*top_iph);
 40         top_iph = ip_hdr(skb);
 41 
 42         top_iph->ihl = 5;
 43         top_iph->version = 4;
 44 
 45         top_iph->protocol = xfrm_af2proto(skb_dst(skb)->ops->family);
 46 
 47         /* DS disclosing depends on XFRM_SA_XFLAG_DONT_ENCAP_DSCP */
 48         if (x->props.extra_flags & XFRM_SA_XFLAG_DONT_ENCAP_DSCP)
 49                 top_iph->tos = 0;
 50         else
 51                 top_iph->tos = XFRM_MODE_SKB_CB(skb)->tos;
 52         top_iph->tos = INET_ECN_encapsulate(top_iph->tos,
 53                                             XFRM_MODE_SKB_CB(skb)->tos);
 54 
 55         flags = x->props.flags;
 56         if (flags & XFRM_STATE_NOECN)
 57                 IP_ECN_clear(top_iph);
 58 
 59         top_iph->frag_off = (flags & XFRM_STATE_NOPMTUDISC) ?
 60                 0 : (XFRM_MODE_SKB_CB(skb)->frag_off & htons(IP_DF));
 61 
 62         top_iph->ttl = ip4_dst_hoplimit(dst->child);
 63 
 64         top_iph->saddr = x->props.saddr.a4;
 65         top_iph->daddr = x->id.daddr.a4;
 66         ip_select_ident(dev_net(dst->dev), skb, NULL);
 67 
 68         return 0;
 69 }
 70 
 71 static int xfrm4_mode_tunnel_input(struct xfrm_state *x, struct sk_buff *skb)
 72 {
 73         int err = -EINVAL;
 74 
 75         if (XFRM_MODE_SKB_CB(skb)->protocol != IPPROTO_IPIP)
 76                 goto out;
 77 
 78         if (!pskb_may_pull(skb, sizeof(struct iphdr)))
 79                 goto out;
 80 
 81         err = skb_unclone(skb, GFP_ATOMIC);
 82         if (err)
 83                 goto out;
 84 
 85         if (x->props.flags & XFRM_STATE_DECAP_DSCP)
 86                 ipv4_copy_dscp(XFRM_MODE_SKB_CB(skb)->tos, ipip_hdr(skb));
 87         if (!(x->props.flags & XFRM_STATE_NOECN))
 88                 ipip_ecn_decapsulate(skb);
 89 
 90         skb_reset_network_header(skb);
 91         skb_mac_header_rebuild(skb);
 92 
 93         err = 0;
 94 
 95 out:
 96         return err;
 97 }
 98 
 99 static struct xfrm_mode xfrm4_tunnel_mode = {
100         .input2 = xfrm4_mode_tunnel_input,
101         .input = xfrm_prepare_input,
102         .output2 = xfrm4_mode_tunnel_output,
103         .output = xfrm4_prepare_output,
104         .owner = THIS_MODULE,
105         .encap = XFRM_MODE_TUNNEL,
106         .flags = XFRM_MODE_FLAG_TUNNEL,
107 };
108 
109 static int __init xfrm4_mode_tunnel_init(void)
110 {
111         return xfrm_register_mode(&xfrm4_tunnel_mode, AF_INET);
112 }
113 
114 static void __exit xfrm4_mode_tunnel_exit(void)
115 {
116         int err;
117 
118         err = xfrm_unregister_mode(&xfrm4_tunnel_mode, AF_INET);
119         BUG_ON(err);
120 }
121 
122 module_init(xfrm4_mode_tunnel_init);
123 module_exit(xfrm4_mode_tunnel_exit);
124 MODULE_LICENSE("GPL");
125 MODULE_ALIAS_XFRM_MODE(AF_INET, XFRM_MODE_TUNNEL);
126 

~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

kernel.org | git.kernel.org | LWN.net | Project Home | Wiki (Japanese) | Wiki (English) | SVN repository | Mail admin

Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.

osdn.jp