Commit 69474a8a authored by Vladimir Nikishkin's avatar Vladimir Nikishkin Committed by David S. Miller
Browse files

net: vxlan: Add nolocalbypass option to vxlan. 



If a packet needs to be encapsulated towards a local destination IP, the
packet will undergo a "local bypass" and be injected into the Rx path as
if it was received by the target VXLAN device without undergoing
encapsulation. If such a device does not exist, the packet will be
dropped.

There are scenarios where we do not want to perform such a bypass, but
instead want the packet to be encapsulated and locally received by a
user space program for post-processing.

To that end, add a new VXLAN device attribute that controls whether a
"local bypass" is performed or not. Default to performing a bypass to
maintain existing behavior.

Signed-off-by: default avatarVladimir Nikishkin <vladimir@nikishkin.pw>
Reviewed-by: default avatarIdo Schimmel <idosch@nvidia.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 7eef636e

drivers/net/vxlan/vxlan_core.c

+19 −2
Original line number Diff line number Diff line
@@ -2352,7 +2352,8 @@ static int encap_bypass_if_local(struct sk_buff *skb, struct net_device *dev, 
#endif

	/* Bypass encapsulation if the destination is local */

	if (rt_flags & RTCF_LOCAL &&

	    !(rt_flags & (RTCF_BROADCAST | RTCF_MULTICAST))) {

	    !(rt_flags & (RTCF_BROADCAST | RTCF_MULTICAST)) &&

	    vxlan->cfg.flags & VXLAN_F_LOCALBYPASS) {

		struct vxlan_dev *dst_vxlan;



		dst_release(dst);
@@ -3172,6 +3173,7 @@ static void vxlan_raw_setup(struct net_device *dev) 
}



static const struct nla_policy vxlan_policy[IFLA_VXLAN_MAX + 1] = {

	[IFLA_VXLAN_UNSPEC]     = { .strict_start_type = IFLA_VXLAN_LOCALBYPASS },

	[IFLA_VXLAN_ID]		= { .type = NLA_U32 },

	[IFLA_VXLAN_GROUP]	= { .len = sizeof_field(struct iphdr, daddr) },

	[IFLA_VXLAN_GROUP6]	= { .len = sizeof(struct in6_addr) },
@@ -3202,6 +3204,7 @@ static const struct nla_policy vxlan_policy[IFLA_VXLAN_MAX + 1] = { 
	[IFLA_VXLAN_TTL_INHERIT]	= { .type = NLA_FLAG },

	[IFLA_VXLAN_DF]		= { .type = NLA_U8 },

	[IFLA_VXLAN_VNIFILTER]	= { .type = NLA_U8 },

	[IFLA_VXLAN_LOCALBYPASS]	= NLA_POLICY_MAX(NLA_U8, 1),

};



static int vxlan_validate(struct nlattr *tb[], struct nlattr *data[],
@@ -4011,6 +4014,17 @@ static int vxlan_nl2conf(struct nlattr *tb[], struct nlattr *data[], 
			conf->flags |= VXLAN_F_UDP_ZERO_CSUM_TX;

	}



	if (data[IFLA_VXLAN_LOCALBYPASS]) {

		err = vxlan_nl2flag(conf, data, IFLA_VXLAN_LOCALBYPASS,

				    VXLAN_F_LOCALBYPASS, changelink,

				    true, extack);

		if (err)

			return err;

	} else if (!changelink) {

		/* default to local bypass on a new device */

		conf->flags |= VXLAN_F_LOCALBYPASS;

	}



	if (data[IFLA_VXLAN_UDP_ZERO_CSUM6_TX]) {

		err = vxlan_nl2flag(conf, data, IFLA_VXLAN_UDP_ZERO_CSUM6_TX,

				    VXLAN_F_UDP_ZERO_CSUM6_TX, changelink,
@@ -4232,6 +4246,7 @@ static size_t vxlan_get_size(const struct net_device *dev) 
		nla_total_size(sizeof(__u8)) + /* IFLA_VXLAN_UDP_ZERO_CSUM6_RX */

		nla_total_size(sizeof(__u8)) + /* IFLA_VXLAN_REMCSUM_TX */

		nla_total_size(sizeof(__u8)) + /* IFLA_VXLAN_REMCSUM_RX */

		nla_total_size(sizeof(__u8)) + /* IFLA_VXLAN_LOCALBYPASS */

		0;

}
@@ -4308,7 +4323,9 @@ static int vxlan_fill_info(struct sk_buff *skb, const struct net_device *dev) 
	    nla_put_u8(skb, IFLA_VXLAN_REMCSUM_TX,

		       !!(vxlan->cfg.flags & VXLAN_F_REMCSUM_TX)) ||

	    nla_put_u8(skb, IFLA_VXLAN_REMCSUM_RX,

		       !!(vxlan->cfg.flags & VXLAN_F_REMCSUM_RX)))

		       !!(vxlan->cfg.flags & VXLAN_F_REMCSUM_RX)) ||

	    nla_put_u8(skb, IFLA_VXLAN_LOCALBYPASS,

		       !!(vxlan->cfg.flags & VXLAN_F_LOCALBYPASS)))

		goto nla_put_failure;



	if (nla_put(skb, IFLA_VXLAN_PORT_RANGE, sizeof(ports), &ports))

include/net/vxlan.h

+3 −1
Original line number Diff line number Diff line
@@ -328,6 +328,7 @@ struct vxlan_dev { 
#define VXLAN_F_TTL_INHERIT		0x10000

#define VXLAN_F_VNIFILTER               0x20000

#define VXLAN_F_MDB			0x40000

#define VXLAN_F_LOCALBYPASS		0x80000



/* Flags that are used in the receive path. These flags must match in

 * order for a socket to be shareable
@@ -348,7 +349,8 @@ struct vxlan_dev { 
					 VXLAN_F_UDP_ZERO_CSUM6_TX |	\

					 VXLAN_F_UDP_ZERO_CSUM6_RX |	\

					 VXLAN_F_COLLECT_METADATA  |	\

					 VXLAN_F_VNIFILTER)

					 VXLAN_F_VNIFILTER         |    \

					 VXLAN_F_LOCALBYPASS)



struct net_device *vxlan_dev_create(struct net *net, const char *name,

				    u8 name_assign_type, struct vxlan_config *conf);

include/uapi/linux/if_link.h

+1 −0
Original line number Diff line number Diff line
@@ -828,6 +828,7 @@ enum { 
	IFLA_VXLAN_TTL_INHERIT,

	IFLA_VXLAN_DF,

	IFLA_VXLAN_VNIFILTER, /* only applicable with COLLECT_METADATA mode */

	IFLA_VXLAN_LOCALBYPASS,

	__IFLA_VXLAN_MAX

};

#define IFLA_VXLAN_MAX	(__IFLA_VXLAN_MAX - 1)