Commit cc9ff19d authored by Timo Teräs's avatar Timo Teräs Committed by David S. Miller
Browse files

xfrm: use gre key as flow upper protocol info 



The GRE Key field is intended to be used for identifying an individual
traffic flow within a tunnel. It is useful to be able to have XFRM
policy selector matches to have different policies for different
GRE tunnels.

Signed-off-by: default avatarTimo Teräs <timo.teras@iki.fi>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent e1f2d8c2

include/net/flow.h

+2 −0
Original line number Diff line number Diff line
@@ -67,6 +67,7 @@ struct flowi { 
		} dnports;



		__be32		spi;

		__be32		gre_key;



		struct {

			__u8	type;
@@ -78,6 +79,7 @@ struct flowi { 
#define fl_icmp_code	uli_u.icmpt.code

#define fl_ipsec_spi	uli_u.spi

#define fl_mh_type	uli_u.mht.type

#define fl_gre_key	uli_u.gre_key

	__u32           secid;	/* used by xfrm; see secid.txt */

} __attribute__((__aligned__(BITS_PER_LONG/8)));

include/net/xfrm.h

+6 −0
Original line number Diff line number Diff line
@@ -805,6 +805,9 @@ __be16 xfrm_flowi_sport(struct flowi *fl) 
	case IPPROTO_MH:

		port = htons(fl->fl_mh_type);

		break;

	case IPPROTO_GRE:

		port = htonl(fl->fl_gre_key) >> 16;

		break;

	default:

		port = 0;	/*XXX*/

	}
@@ -826,6 +829,9 @@ __be16 xfrm_flowi_dport(struct flowi *fl) 
	case IPPROTO_ICMPV6:

		port = htons(fl->fl_icmp_code);

		break;

	case IPPROTO_GRE:

		port = htonl(fl->fl_gre_key) & 0xffff;

		break;

	default:

		port = 0;	/*XXX*/

	}

net/ipv4/ip_gre.c

+7 −5
Original line number Diff line number Diff line
@@ -779,9 +779,9 @@ static netdev_tx_t ipgre_tunnel_xmit(struct sk_buff *skb, struct net_device *dev 
					.tos = RT_TOS(tos)

				}

			},

			.proto = IPPROTO_GRE

		}

;

			.proto = IPPROTO_GRE,

			.fl_gre_key = tunnel->parms.o_key

		};

		if (ip_route_output_key(dev_net(dev), &rt, &fl)) {

			dev->stats.tx_carrier_errors++;

			goto tx_error;
@@ -958,7 +958,8 @@ static int ipgre_tunnel_bind_dev(struct net_device *dev) 
					.tos = RT_TOS(iph->tos)

				}

			},

			.proto = IPPROTO_GRE

			.proto = IPPROTO_GRE,

			.fl_gre_key = tunnel->parms.o_key

		};

		struct rtable *rt;
@@ -1223,7 +1224,8 @@ static int ipgre_open(struct net_device *dev) 
					.tos = RT_TOS(t->parms.iph.tos)

				}

			},

			.proto = IPPROTO_GRE

			.proto = IPPROTO_GRE,

			.fl_gre_key = t->parms.o_key

		};

		struct rtable *rt;

net/ipv4/xfrm4_policy.c

+15 −0
Original line number Diff line number Diff line
@@ -11,6 +11,7 @@ 
#include <linux/err.h>

#include <linux/kernel.h>

#include <linux/inetdevice.h>

#include <linux/if_tunnel.h>

#include <net/dst.h>

#include <net/xfrm.h>

#include <net/ip.h>
@@ -154,6 +155,20 @@ _decode_session4(struct sk_buff *skb, struct flowi *fl, int reverse) 
				fl->fl_ipsec_spi = htonl(ntohs(ipcomp_hdr[1]));

			}

			break;



		case IPPROTO_GRE:

			if (pskb_may_pull(skb, xprth + 12 - skb->data)) {

				__be16 *greflags = (__be16 *)xprth;

				__be32 *gre_hdr = (__be32 *)xprth;



				if (greflags[0] & GRE_KEY) {

					if (greflags[0] & GRE_CSUM)

						gre_hdr++;

					fl->fl_gre_key = gre_hdr[1];

				}

			}

			break;



		default:

			fl->fl_ipsec_spi = 0;

			break;

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