[PATCH net-next 2/4] tc: flower: support for SPI

[Ratheesh Kannoth]

tc flower rules support to classify ESP/AH
packets matching SPI field.

Signed-off-by: Ratheesh Kannoth <rkannoth@xxxxxxxxxxx>
---
 include/uapi/linux/pkt_cls.h |  3 +++
 net/sched/cls_flower.c       | 35 +++++++++++++++++++++++++++++++++++
 2 files changed, 38 insertions(+)

diff --git a/include/uapi/linux/pkt_cls.h b/include/uapi/linux/pkt_cls.h
index 7865f5a9885b..a90b0e3d351f 100644
--- a/include/uapi/linux/pkt_cls.h
+++ b/include/uapi/linux/pkt_cls.h
@@ -594,6 +594,9 @@ enum {
 
 	TCA_FLOWER_KEY_L2TPV3_SID,	/* be32 */
 
+	TCA_FLOWER_KEY_SPI,		/* be32 */
+	TCA_FLOWER_KEY_SPI_MASK,	/* be32 */
+
 	TCA_FLOWER_L2_MISS,		/* u8 */
 
 	TCA_FLOWER_KEY_CFM,		/* nested */
diff --git a/net/sched/cls_flower.c b/net/sched/cls_flower.c
index 8da9d039d964..eca260272845 100644
--- a/net/sched/cls_flower.c
+++ b/net/sched/cls_flower.c
@@ -72,6 +72,7 @@ struct fl_flow_key {
 	struct flow_dissector_key_num_of_vlans num_of_vlans;
 	struct flow_dissector_key_pppoe pppoe;
 	struct flow_dissector_key_l2tpv3 l2tpv3;
+	struct flow_dissector_key_ipsec ipsec;
 	struct flow_dissector_key_cfm cfm;
 } __aligned(BITS_PER_LONG / 8); /* Ensure that we can do comparisons as longs. */
 
@@ -726,6 +727,8 @@ static const struct nla_policy fl_policy[TCA_FLOWER_MAX + 1] = {
 	[TCA_FLOWER_KEY_PPPOE_SID]	= { .type = NLA_U16 },
 	[TCA_FLOWER_KEY_PPP_PROTO]	= { .type = NLA_U16 },
 	[TCA_FLOWER_KEY_L2TPV3_SID]	= { .type = NLA_U32 },
+	[TCA_FLOWER_KEY_SPI]		= { .type = NLA_U32 },
+	[TCA_FLOWER_KEY_SPI_MASK]	= { .type = NLA_U32 },
 	[TCA_FLOWER_L2_MISS]		= NLA_POLICY_MAX(NLA_U8, 1),
 	[TCA_FLOWER_KEY_CFM]		= { .type = NLA_NESTED },
 };
@@ -795,6 +798,24 @@ static void fl_set_key_val(struct nlattr **tb,
 		nla_memcpy(mask, tb[mask_type], len);
 }
 
+static int fl_set_key_spi(struct nlattr **tb, struct fl_flow_key *key,
+			  struct fl_flow_key *mask,
+			  struct netlink_ext_ack *extack)
+{
+	if (key->basic.ip_proto != IPPROTO_ESP &&
+	    key->basic.ip_proto != IPPROTO_AH) {
+		NL_SET_ERR_MSG(extack,
+			       "Protocol must be either ESP or AH");
+		return -EINVAL;
+	}
+
+	fl_set_key_val(tb, &key->ipsec.spi,
+		       TCA_FLOWER_KEY_SPI,
+		       &mask->ipsec.spi, TCA_FLOWER_KEY_SPI_MASK,
+		       sizeof(key->ipsec.spi));
+	return 0;
+}
+
 static int fl_set_key_port_range(struct nlattr **tb, struct fl_flow_key *key,
 				 struct fl_flow_key *mask,
 				 struct netlink_ext_ack *extack)
@@ -1894,6 +1915,12 @@ static int fl_set_key(struct net *net, struct nlattr **tb,
 			return ret;
 	}
 
+	if (tb[TCA_FLOWER_KEY_SPI]) {
+		ret = fl_set_key_spi(tb, key, mask, extack);
+		if (ret)
+			return ret;
+	}
+
 	if (tb[TCA_FLOWER_KEY_ENC_IPV4_SRC] ||
 	    tb[TCA_FLOWER_KEY_ENC_IPV4_DST]) {
 		key->enc_control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
@@ -2066,6 +2093,8 @@ static void fl_init_dissector(struct flow_dissector *dissector,
 			     FLOW_DISSECTOR_KEY_PPPOE, pppoe);
 	FL_KEY_SET_IF_MASKED(mask, keys, cnt,
 			     FLOW_DISSECTOR_KEY_L2TPV3, l2tpv3);
+	FL_KEY_SET_IF_MASKED(mask, keys, cnt,
+			     FLOW_DISSECTOR_KEY_IPSEC, ipsec);
 	FL_KEY_SET_IF_MASKED(mask, keys, cnt,
 			     FLOW_DISSECTOR_KEY_CFM, cfm);
 
@@ -3364,6 +3393,12 @@ static int fl_dump_key(struct sk_buff *skb, struct net *net,
 				 sizeof(key->l2tpv3.session_id)))
 		goto nla_put_failure;
 
+	if (key->ipsec.spi &&
+	    fl_dump_key_val(skb, &key->ipsec.spi, TCA_FLOWER_KEY_SPI,
+			    &mask->ipsec.spi, TCA_FLOWER_KEY_SPI_MASK,
+			    sizeof(key->ipsec.spi)))
+		goto nla_put_failure;
+
 	if ((key->basic.ip_proto == IPPROTO_TCP ||
 	     key->basic.ip_proto == IPPROTO_UDP ||
 	     key->basic.ip_proto == IPPROTO_SCTP) &&
-- 
2.25.1