diff options
Diffstat (limited to '')
| -rw-r--r-- | net/ipv6/xfrm6_mode_tunnel.c | 151 |
1 files changed, 151 insertions, 0 deletions
diff --git a/net/ipv6/xfrm6_mode_tunnel.c b/net/ipv6/xfrm6_mode_tunnel.c new file mode 100644 index 000000000..de1b0b8c5 --- /dev/null +++ b/net/ipv6/xfrm6_mode_tunnel.c @@ -0,0 +1,151 @@ +/* + * xfrm6_mode_tunnel.c - Tunnel mode encapsulation for IPv6. + * + * Copyright (C) 2002 USAGI/WIDE Project + * Copyright (c) 2004-2006 Herbert Xu <herbert@gondor.apana.org.au> + */ + +#include <linux/gfp.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/skbuff.h> +#include <linux/stringify.h> +#include <net/dsfield.h> +#include <net/dst.h> +#include <net/inet_ecn.h> +#include <net/ip6_route.h> +#include <net/ipv6.h> +#include <net/xfrm.h> + +static inline void ipip6_ecn_decapsulate(struct sk_buff *skb) +{ + struct ipv6hdr *inner_iph = ipipv6_hdr(skb); + + if (INET_ECN_is_ce(XFRM_MODE_SKB_CB(skb)->tos)) + IP6_ECN_set_ce(skb, inner_iph); +} + +/* Add encapsulation header. + * + * The top IP header will be constructed per RFC 2401. + */ +static int xfrm6_mode_tunnel_output(struct xfrm_state *x, struct sk_buff *skb) +{ + struct dst_entry *dst = skb_dst(skb); + struct ipv6hdr *top_iph; + int dsfield; + + skb_set_inner_network_header(skb, skb_network_offset(skb)); + skb_set_inner_transport_header(skb, skb_transport_offset(skb)); + + skb_set_network_header(skb, -x->props.header_len); + skb->mac_header = skb->network_header + + offsetof(struct ipv6hdr, nexthdr); + skb->transport_header = skb->network_header + sizeof(*top_iph); + top_iph = ipv6_hdr(skb); + + top_iph->version = 6; + + memcpy(top_iph->flow_lbl, XFRM_MODE_SKB_CB(skb)->flow_lbl, + sizeof(top_iph->flow_lbl)); + top_iph->nexthdr = xfrm_af2proto(skb_dst(skb)->ops->family); + + if (x->props.extra_flags & XFRM_SA_XFLAG_DONT_ENCAP_DSCP) + dsfield = 0; + else + dsfield = XFRM_MODE_SKB_CB(skb)->tos; + dsfield = INET_ECN_encapsulate(dsfield, XFRM_MODE_SKB_CB(skb)->tos); + if (x->props.flags & XFRM_STATE_NOECN) + dsfield &= ~INET_ECN_MASK; + ipv6_change_dsfield(top_iph, 0, dsfield); + top_iph->hop_limit = ip6_dst_hoplimit(xfrm_dst_child(dst)); + top_iph->saddr = *(struct in6_addr *)&x->props.saddr; + top_iph->daddr = *(struct in6_addr *)&x->id.daddr; + return 0; +} + +#define for_each_input_rcu(head, handler) \ + for (handler = rcu_dereference(head); \ + handler != NULL; \ + handler = rcu_dereference(handler->next)) + + +static int xfrm6_mode_tunnel_input(struct xfrm_state *x, struct sk_buff *skb) +{ + int err = -EINVAL; + + if (XFRM_MODE_SKB_CB(skb)->protocol != IPPROTO_IPV6) + goto out; + if (!pskb_may_pull(skb, sizeof(struct ipv6hdr))) + goto out; + + err = skb_unclone(skb, GFP_ATOMIC); + if (err) + goto out; + + if (x->props.flags & XFRM_STATE_DECAP_DSCP) + ipv6_copy_dscp(ipv6_get_dsfield(ipv6_hdr(skb)), + ipipv6_hdr(skb)); + if (!(x->props.flags & XFRM_STATE_NOECN)) + ipip6_ecn_decapsulate(skb); + + skb_reset_network_header(skb); + skb_mac_header_rebuild(skb); + if (skb->mac_len) + eth_hdr(skb)->h_proto = skb->protocol; + + err = 0; + +out: + return err; +} + +static struct sk_buff *xfrm6_mode_tunnel_gso_segment(struct xfrm_state *x, + struct sk_buff *skb, + netdev_features_t features) +{ + __skb_push(skb, skb->mac_len); + return skb_mac_gso_segment(skb, features); +} + +static void xfrm6_mode_tunnel_xmit(struct xfrm_state *x, struct sk_buff *skb) +{ + struct xfrm_offload *xo = xfrm_offload(skb); + + if (xo->flags & XFRM_GSO_SEGMENT) + skb->transport_header = skb->network_header + sizeof(struct ipv6hdr); + + skb_reset_mac_len(skb); + pskb_pull(skb, skb->mac_len + x->props.header_len); +} + +static struct xfrm_mode xfrm6_tunnel_mode = { + .input2 = xfrm6_mode_tunnel_input, + .input = xfrm_prepare_input, + .output2 = xfrm6_mode_tunnel_output, + .output = xfrm6_prepare_output, + .gso_segment = xfrm6_mode_tunnel_gso_segment, + .xmit = xfrm6_mode_tunnel_xmit, + .owner = THIS_MODULE, + .encap = XFRM_MODE_TUNNEL, + .flags = XFRM_MODE_FLAG_TUNNEL, +}; + +static int __init xfrm6_mode_tunnel_init(void) +{ + return xfrm_register_mode(&xfrm6_tunnel_mode, AF_INET6); +} + +static void __exit xfrm6_mode_tunnel_exit(void) +{ + int err; + + err = xfrm_unregister_mode(&xfrm6_tunnel_mode, AF_INET6); + BUG_ON(err); +} + +module_init(xfrm6_mode_tunnel_init); +module_exit(xfrm6_mode_tunnel_exit); +MODULE_LICENSE("GPL"); +MODULE_ALIAS_XFRM_MODE(AF_INET6, XFRM_MODE_TUNNEL); |