[PATCHv2 net-next 2/2] openvswitch: add erspan version II support

[William Tu <u9012063@gmail.com>]

The patch adds support for configuring the erspan V2 fields for
openvswitch.  For compatibility reason, the previously added
attribute 'OVS_TUNNEL_KEY_ATTR_ERSPAN_OPTS' is renamed to
'OVS_TUNNEL_KEY_ATTR_ERSPAN_OPTSV1' and deprecated, and the newly added
attribute 'OVS_TUNNEL_KEY_ATTR_ERSPAN_OPTS' will handle both V1 and V2.

Signed-off-by: William Tu <u9012063@gmail.com>
Cc: Pravin B Shelar <pshelar@ovn.org>
---
 include/uapi/linux/openvswitch.h |  13 +++-
 net/openvswitch/flow_netlink.c   | 129 ++++++++++++++++++++++++++++++++++++---
 2 files changed, 132 insertions(+), 10 deletions(-)

diff --git a/include/uapi/linux/openvswitch.h b/include/uapi/linux/openvswitch.h
index 4265d7f9e1f2..77c3424cc4ef 100644
--- a/include/uapi/linux/openvswitch.h
+++ b/include/uapi/linux/openvswitch.h
@@ -273,6 +273,16 @@ enum {
 
 #define OVS_VXLAN_EXT_MAX (__OVS_VXLAN_EXT_MAX - 1)
 
+enum {
+	OVS_ERSPAN_OPT_UNSPEC,
+	OVS_ERSPAN_OPT_IDX,	/* be32 index */
+	OVS_ERSPAN_OPT_VER,	/* u8 version number */
+	OVS_ERSPAN_OPT_DIR,	/* u8 direction */
+	OVS_ERSPAN_OPT_HWID,	/* u8 hardware ID */
+	__OVS_ERSPAN_OPT_MAX,
+};
+
+#define OVS_ERSPAN_OPT_MAX (__OVS_ERSPAN_OPT_MAX - 1)
 
 /* OVS_VPORT_ATTR_OPTIONS attributes for tunnels.
  */
@@ -363,7 +373,8 @@ enum ovs_tunnel_key_attr {
 	OVS_TUNNEL_KEY_ATTR_IPV6_SRC,		/* struct in6_addr src IPv6 address. */
 	OVS_TUNNEL_KEY_ATTR_IPV6_DST,		/* struct in6_addr dst IPv6 address. */
 	OVS_TUNNEL_KEY_ATTR_PAD,
-	OVS_TUNNEL_KEY_ATTR_ERSPAN_OPTS,	/* be32 ERSPAN index. */
+	OVS_TUNNEL_KEY_ATTR_ERSPAN_OPTSV1,	/* be32 ERSPAN v1 index (deprecated). */
+	OVS_TUNNEL_KEY_ATTR_ERSPAN_OPTS,	/* Nested OVS_ERSPAN_OPT_* */
 	__OVS_TUNNEL_KEY_ATTR_MAX
 };
 
diff --git a/net/openvswitch/flow_netlink.c b/net/openvswitch/flow_netlink.c
index bce1f78b0de5..9c6b210e7893 100644
--- a/net/openvswitch/flow_netlink.c
+++ b/net/openvswitch/flow_netlink.c
@@ -335,7 +335,10 @@ size_t ovs_tun_key_attr_size(void)
 		 */
 		+ nla_total_size(2)    /* OVS_TUNNEL_KEY_ATTR_TP_SRC */
 		+ nla_total_size(2)    /* OVS_TUNNEL_KEY_ATTR_TP_DST */
-		+ nla_total_size(4);   /* OVS_TUNNEL_KEY_ATTR_ERSPAN_OPTS */
+		+ nla_total_size(4);   /* OVS_TUNNEL_KEY_ATTR_ERSPAN_OPTSV1 */
+		/* OVS_TUNNEL_KEY_ATTR_ERSPAN_OPTS is mutually exclusive with
+		 * OVS_TUNNEL_KEY_ATTR_GENEVE_OPTS and covered by it.
+		 */
 }
 
 static size_t ovs_nsh_key_attr_size(void)
@@ -386,6 +389,13 @@ static const struct ovs_len_tbl ovs_vxlan_ext_key_lens[OVS_VXLAN_EXT_MAX + 1] =
 	[OVS_VXLAN_EXT_GBP]	    = { .len = sizeof(u32) },
 };
 
+static const struct ovs_len_tbl ovs_erspan_opt_lens[OVS_ERSPAN_OPT_MAX + 1] = {
+	[OVS_ERSPAN_OPT_IDX]	= { .len = sizeof(u32) },
+	[OVS_ERSPAN_OPT_VER]	= { .len = sizeof(u8) },
+	[OVS_ERSPAN_OPT_DIR]	= { .len = sizeof(u8) },
+	[OVS_ERSPAN_OPT_HWID]	= { .len = sizeof(u8) },
+};
+
 static const struct ovs_len_tbl ovs_tunnel_key_lens[OVS_TUNNEL_KEY_ATTR_MAX + 1] = {
 	[OVS_TUNNEL_KEY_ATTR_ID]	    = { .len = sizeof(u64) },
 	[OVS_TUNNEL_KEY_ATTR_IPV4_SRC]	    = { .len = sizeof(u32) },
@@ -402,7 +412,9 @@ static const struct ovs_len_tbl ovs_tunnel_key_lens[OVS_TUNNEL_KEY_ATTR_MAX + 1]
 						.next = ovs_vxlan_ext_key_lens },
 	[OVS_TUNNEL_KEY_ATTR_IPV6_SRC]      = { .len = sizeof(struct in6_addr) },
 	[OVS_TUNNEL_KEY_ATTR_IPV6_DST]      = { .len = sizeof(struct in6_addr) },
-	[OVS_TUNNEL_KEY_ATTR_ERSPAN_OPTS]   = { .len = sizeof(u32) },
+	[OVS_TUNNEL_KEY_ATTR_ERSPAN_OPTSV1] = { .len = sizeof(u32) },
+	[OVS_TUNNEL_KEY_ATTR_ERSPAN_OPTS]   = { .len = OVS_ATTR_NESTED,
+						.next = ovs_erspan_opt_lens },
 };
 
 static const struct ovs_len_tbl
@@ -640,16 +652,78 @@ static int erspan_tun_opt_from_nlattr(const struct nlattr *attr,
 {
 	unsigned long opt_key_offset;
 	struct erspan_metadata opts;
+	struct nlattr *a;
+	u16 hwid, dir;
+	int rem;
 
 	BUILD_BUG_ON(sizeof(opts) > sizeof(match->key->tun_opts));
 
 	memset(&opts, 0, sizeof(opts));
-	opts.u.index = nla_get_be32(attr);
+	nla_for_each_nested(a, attr, rem) {
+		int type = nla_type(a);
+
+		if (type > OVS_ERSPAN_OPT_MAX) {
+			OVS_NLERR(log, "ERSPAN option %d out of range max %d",
+				  type, OVS_ERSPAN_OPT_MAX);
+			return -EINVAL;
+		}
+
+		if (!check_attr_len(nla_len(a),
+				    ovs_erspan_opt_lens[type].len)) {
+			OVS_NLERR(log, "ERSPAN option %d has unexpected len %d expected %d",
+				  type, nla_len(a),
+				  ovs_erspan_opt_lens[type].len);
+			return -EINVAL;
+		}
 
-	/* Index has only 20-bit */
-	if (ntohl(opts.u.index) & ~INDEX_MASK) {
-		OVS_NLERR(log, "ERSPAN index number %x too large.",
-			  ntohl(opts.u.index));
+		switch (type) {
+		case OVS_ERSPAN_OPT_IDX:
+			opts.u.index = nla_get_be32(a);
+			if (ntohl(opts.u.index) & ~INDEX_MASK) {
+				OVS_NLERR(log,
+					  "ERSPAN index number %x too large.",
+					  ntohl(opts.u.index));
+				return -EINVAL;
+			}
+			break;
+		case OVS_ERSPAN_OPT_VER:
+			opts.version = nla_get_u8(a);
+			if (opts.version != 1 && opts.version != 2) {
+				OVS_NLERR(log,
+					  "ERSPAN version %d not supported.",
+					  opts.version);
+				return -EINVAL;
+			}
+			break;
+		case OVS_ERSPAN_OPT_DIR:
+			dir = nla_get_u8(a);
+			if (dir != 0 && dir != 1) {
+				OVS_NLERR(log,
+					  "ERSPAN direction %d invalid.",
+					  dir);
+				return -EINVAL;
+			}
+			opts.u.md2.dir = dir;
+			break;
+		case OVS_ERSPAN_OPT_HWID:
+			hwid = nla_get_u8(a);
+			if (hwid & ~(HWID_MASK >> HWID_OFFSET)) {
+				OVS_NLERR(log,
+					  "ERSPAN hardware ID %x invalid.",
+					  hwid);
+				return -EINVAL;
+			}
+			set_hwid(&opts.u.md2, hwid);
+			break;
+		default:
+			OVS_NLERR(log, "Unknown ERSPAN opt attribute %d",
+				  type);
+			return -EINVAL;
+		}
+	}
+	if (rem) {
+		OVS_NLERR(log, "ERSPAN opt message has %d unknown bytes.",
+			  rem);
 		return -EINVAL;
 	}
 
@@ -768,6 +842,10 @@ static int ip_tun_from_nlattr(const struct nlattr *attr,
 			break;
 		case OVS_TUNNEL_KEY_ATTR_PAD:
 			break;
+		case OVS_TUNNEL_KEY_ATTR_ERSPAN_OPTSV1:
+			OVS_NLERR(log, "ERSPAN attribute %d is deprecated.",
+				  type);
+			return -EINVAL;
 		case OVS_TUNNEL_KEY_ATTR_ERSPAN_OPTS:
 			if (opts_type) {
 				OVS_NLERR(log, "Multiple metadata blocks provided");
@@ -846,6 +924,39 @@ static int vxlan_opt_to_nlattr(struct sk_buff *skb,
 	return 0;
 }
 
+static int erspan_opt_to_nlattr(struct sk_buff *skb,
+				const void *tun_opts, int swkey_tun_opts_len)
+{
+	const struct erspan_metadata *opts = tun_opts;
+	struct nlattr *nla;
+
+	nla = nla_nest_start(skb, OVS_TUNNEL_KEY_ATTR_ERSPAN_OPTS);
+	if (!nla)
+		return -EMSGSIZE;
+
+	if (nla_put_u8(skb, OVS_ERSPAN_OPT_VER, opts->version) < 0)
+		return -EMSGSIZE;
+
+	if (opts->version == 1) {
+		if (nla_put_be32(skb, OVS_ERSPAN_OPT_IDX, opts->u.index) < 0)
+			return -EMSGSIZE;
+
+	} else if (opts->version == 2) {
+		if (nla_put_u8(skb, OVS_ERSPAN_OPT_DIR,
+			       opts->u.md2.dir) < 0)
+			return -EMSGSIZE;
+
+		if (nla_put_u8(skb, OVS_ERSPAN_OPT_HWID,
+			       get_hwid(&opts->u.md2)) < 0)
+			return -EMSGSIZE;
+	} else {
+		return -EINVAL;
+	}
+
+	nla_nest_end(skb, nla);
+	return 0;
+}
+
 static int __ip_tun_to_nlattr(struct sk_buff *skb,
 			      const struct ip_tunnel_key *output,
 			      const void *tun_opts, int swkey_tun_opts_len,
@@ -906,8 +1017,8 @@ static int __ip_tun_to_nlattr(struct sk_buff *skb,
 			 vxlan_opt_to_nlattr(skb, tun_opts, swkey_tun_opts_len))
 			return -EMSGSIZE;
 		else if (output->tun_flags & TUNNEL_ERSPAN_OPT &&
-			 nla_put_be32(skb, OVS_TUNNEL_KEY_ATTR_ERSPAN_OPTS,
-				      ((struct erspan_metadata *)tun_opts)->u.index))
+			 erspan_opt_to_nlattr(skb, tun_opts,
+					      swkey_tun_opts_len))
 			return -EMSGSIZE;
 	}
 
-- 
2.7.4