From 3511494ce2f3d3b77544c79b87511a4ddb61dc89 Mon Sep 17 00:00:00 2001 From: Thomas Graf Date: Thu, 15 Jan 2015 03:53:55 +0100 Subject: vxlan: Group Policy extension Implements supports for the Group Policy VXLAN extension [0] to provide a lightweight and simple security label mechanism across network peers based on VXLAN. The security context and associated metadata is mapped to/from skb->mark. This allows further mapping to a SELinux context using SECMARK, to implement ACLs directly with nftables, iptables, OVS, tc, etc. The group membership is defined by the lower 16 bits of skb->mark, the upper 16 bits are used for flags. SELinux allows to manage label to secure local resources. However, distributed applications require ACLs to implemented across hosts. This is typically achieved by matching on L2-L4 fields to identify the original sending host and process on the receiver. On top of that, netlabel and specifically CIPSO [1] allow to map security contexts to universal labels. However, netlabel and CIPSO are relatively complex. This patch provides a lightweight alternative for overlay network environments with a trusted underlay. No additional control protocol is required. Host 1: Host 2: Group A Group B Group B Group A +-----+ +-------------+ +-------+ +-----+ | lxc | | SELinux CTX | | httpd | | VM | +--+--+ +--+----------+ +---+---+ +--+--+ \---+---/ \----+---/ | | +---+---+ +---+---+ | vxlan | | vxlan | +---+---+ +---+---+ +------------------------------+ Backwards compatibility: A VXLAN-GBP socket can receive standard VXLAN frames and will assign the default group 0x0000 to such frames. A Linux VXLAN socket will drop VXLAN-GBP frames. The extension is therefore disabled by default and needs to be specifically enabled: ip link add [...] type vxlan [...] gbp In a mixed environment with VXLAN and VXLAN-GBP sockets, the GBP socket must run on a separate port number. Examples: iptables: host1# iptables -I OUTPUT -m owner --uid-owner 101 -j MARK --set-mark 0x200 host2# iptables -I INPUT -m mark --mark 0x200 -j DROP OVS: # ovs-ofctl add-flow br0 'in_port=1,actions=load:0x200->NXM_NX_TUN_GBP_ID[],NORMAL' # ovs-ofctl add-flow br0 'in_port=2,tun_gbp_id=0x200,actions=drop' [0] https://tools.ietf.org/html/draft-smith-vxlan-group-policy [1] http://lwn.net/Articles/204905/ Signed-off-by: Thomas Graf Signed-off-by: David S. Miller --- include/uapi/linux/if_link.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/uapi/linux') diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h index b2723f65846f..2a8380edbb7e 100644 --- a/include/uapi/linux/if_link.h +++ b/include/uapi/linux/if_link.h @@ -372,6 +372,7 @@ enum { IFLA_VXLAN_UDP_ZERO_CSUM6_RX, IFLA_VXLAN_REMCSUM_TX, IFLA_VXLAN_REMCSUM_RX, + IFLA_VXLAN_GBP, __IFLA_VXLAN_MAX }; #define IFLA_VXLAN_MAX (__IFLA_VXLAN_MAX - 1) -- cgit v1.2.3 From 1dd144cf5b4b47e12438c2c6883925ce1a9b499f Mon Sep 17 00:00:00 2001 From: Thomas Graf Date: Thu, 15 Jan 2015 03:53:59 +0100 Subject: openvswitch: Support VXLAN Group Policy extension Introduces support for the group policy extension to the VXLAN virtual port. The extension is disabled by default and only enabled if the user has provided the respective configuration. ovs-vsctl add-port br0 vxlan0 -- \ set Interface vxlan0 type=vxlan options:exts=gbp The configuration interface to enable the extension is based on a new attribute OVS_VXLAN_EXT_GBP nested inside OVS_TUNNEL_ATTR_EXTENSION which can carry additional extensions as needed in the future. The group policy metadata is stored as binary blob (struct ovs_vxlan_opts) internally just like Geneve options but transported as nested Netlink attributes to user space. Renames the existing TUNNEL_OPTIONS_PRESENT to TUNNEL_GENEVE_OPT with the binary value kept intact, a new flag TUNNEL_VXLAN_OPT is introduced. The attributes OVS_TUNNEL_KEY_ATTR_VXLAN_OPTS and existing OVS_TUNNEL_KEY_ATTR_GENEVE_OPTS are implemented mutually exclusive. Signed-off-by: Thomas Graf Signed-off-by: David S. Miller --- include/uapi/linux/openvswitch.h | 11 +++++++++++ 1 file changed, 11 insertions(+) (limited to 'include/uapi/linux') diff --git a/include/uapi/linux/openvswitch.h b/include/uapi/linux/openvswitch.h index f714e8633352..cd8d933963c2 100644 --- a/include/uapi/linux/openvswitch.h +++ b/include/uapi/linux/openvswitch.h @@ -252,11 +252,21 @@ enum ovs_vport_attr { #define OVS_VPORT_ATTR_MAX (__OVS_VPORT_ATTR_MAX - 1) +enum { + OVS_VXLAN_EXT_UNSPEC, + OVS_VXLAN_EXT_GBP, /* Flag or __u32 */ + __OVS_VXLAN_EXT_MAX, +}; + +#define OVS_VXLAN_EXT_MAX (__OVS_VXLAN_EXT_MAX - 1) + + /* OVS_VPORT_ATTR_OPTIONS attributes for tunnels. */ enum { OVS_TUNNEL_ATTR_UNSPEC, OVS_TUNNEL_ATTR_DST_PORT, /* 16-bit UDP port, used by L4 tunnels. */ + OVS_TUNNEL_ATTR_EXTENSION, __OVS_TUNNEL_ATTR_MAX }; @@ -328,6 +338,7 @@ enum ovs_tunnel_key_attr { OVS_TUNNEL_KEY_ATTR_GENEVE_OPTS, /* Array of Geneve options. */ OVS_TUNNEL_KEY_ATTR_TP_SRC, /* be16 src Transport Port. */ OVS_TUNNEL_KEY_ATTR_TP_DST, /* be16 dst Transport Port. */ + OVS_TUNNEL_KEY_ATTR_VXLAN_OPTS, /* Nested OVS_VXLAN_EXT_* */ __OVS_TUNNEL_KEY_ATTR_MAX }; -- cgit v1.2.3