[PATCH net-next v5 0/2] net/sched: cls_flower: Support matching on ICMP

[PATCH net-next v5 0/2] net/sched: cls_flower: Support matching on ICMP

[Simon Horman]

Hi,

this series adds support for matching on ICMP type and code to cls_flower.

Changes v4->v5:
* Drop all helpers

Changes v3->v4:
* Do not add icmp to struct flow_keys, it is not needed
* Do not test for ICMP protocols in packet in __skb_flow_dissect,
  this is also not needed

Changes v2->v3:
* Add FLOW_DISSECTOR_KEY_ICMP and use separate structure for ICMP

Changes v1->v2:
* Include all dissector helpers in first patch


Simon Horman (2):
  flow dissector: ICMP support
  net/sched: cls_flower: Support matching on ICMP type and code

 include/net/flow_dissector.h | 17 ++++++++++++++
 include/uapi/linux/pkt_cls.h | 10 +++++++++
 net/core/flow_dissector.c    | 31 ++++++++++++++++++++++++++
 net/sched/cls_flower.c       | 53 ++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 111 insertions(+)

-- 
2.7.0.rc3.207.g0ac5344

[PATCH net-next v5 1/2] flow dissector: ICMP support

[Simon Horman]

Allow dissection of ICMP(V6) type and code. This should only occur
if a packet is ICMP(V6) and the dissector has FLOW_DISSECTOR_KEY_ICMP set.

There are currently no users of FLOW_DISSECTOR_KEY_ICMP.
A follow-up patch will allow FLOW_DISSECTOR_KEY_ICMP to be used by
the flower classifier.
---
v5
* Drop remaining helpers

v4
* Do not add icmp to struct flow_keys, it is not needed
* Do not test for ICMP protocols in packet in __skb_flow_dissect,
  this is also not needed
* Drop now unnecessary helpers

v3
* Add FLOW_DISSECTOR_KEY_ICMP and use separate structure for ICMP, struct
  flow_dissector_key_icmp, which is a union with struct
  flow_dissector_key_ports in struct flow_keys.
* Drop checks for !ICMP before accessing port field

v2
* Include all helpers in this patch
---
 include/net/flow_dissector.h | 17 +++++++++++++++++
 net/core/flow_dissector.c    | 31 +++++++++++++++++++++++++++++++
 2 files changed, 48 insertions(+)

diff --git a/include/net/flow_dissector.h b/include/net/flow_dissector.h
index c4f31666afd2..d896a33e00d4 100644
--- a/include/net/flow_dissector.h
+++ b/include/net/flow_dissector.h
@@ -104,6 +104,22 @@ struct flow_dissector_key_ports {
 	};
 };
 
+/**
+ * flow_dissector_key_icmp:
+ *	@ports: type and code of ICMP header
+ *		icmp: ICMP type (high) and code (low)
+ *		type: ICMP type
+ *		code: ICMP code
+ */
+struct flow_dissector_key_icmp {
+	union {
+		__be16 icmp;
+		struct {
+			u8 type;
+			u8 code;
+		};
+	};
+};
 
 /**
  * struct flow_dissector_key_eth_addrs:
@@ -122,6 +138,7 @@ enum flow_dissector_key_id {
 	FLOW_DISSECTOR_KEY_IPV4_ADDRS, /* struct flow_dissector_key_ipv4_addrs */
 	FLOW_DISSECTOR_KEY_IPV6_ADDRS, /* struct flow_dissector_key_ipv6_addrs */
 	FLOW_DISSECTOR_KEY_PORTS, /* struct flow_dissector_key_ports */
+	FLOW_DISSECTOR_KEY_ICMP, /* struct flow_dissector_key_icmp */
 	FLOW_DISSECTOR_KEY_ETH_ADDRS, /* struct flow_dissector_key_eth_addrs */
 	FLOW_DISSECTOR_KEY_TIPC_ADDRS, /* struct flow_dissector_key_tipc_addrs */
 	FLOW_DISSECTOR_KEY_VLAN, /* struct flow_dissector_key_flow_vlan */
diff --git a/net/core/flow_dissector.c b/net/core/flow_dissector.c
index 1eb6f949e5b2..d6447dc10371 100644
--- a/net/core/flow_dissector.c
+++ b/net/core/flow_dissector.c
@@ -58,6 +58,28 @@ void skb_flow_dissector_init(struct flow_dissector *flow_dissector,
 EXPORT_SYMBOL(skb_flow_dissector_init);
 
 /**
+ * skb_flow_get_be16 - extract be16 entity
+ * @skb: sk_buff to extract from
+ * @poff: offset to extract at
+ * @data: raw buffer pointer to the packet
+ * @hlen: packet header length
+ *
+ * The function will try to retrieve a be32 entity at
+ * offset poff
+ */
+__be16 skb_flow_get_be16(const struct sk_buff *skb, int poff, void *data,
+			 int hlen)
+{
+	__be16 *u, _u;
+
+	u = __skb_header_pointer(skb, poff, sizeof(_u), data, hlen, &_u);
+	if (u)
+		return *u;
+
+	return 0;
+}
+
+/**
  * __skb_flow_get_ports - extract the upper layer ports and return them
  * @skb: sk_buff to extract the ports from
  * @thoff: transport header offset
@@ -117,6 +139,7 @@ bool __skb_flow_dissect(const struct sk_buff *skb,
 	struct flow_dissector_key_basic *key_basic;
 	struct flow_dissector_key_addrs *key_addrs;
 	struct flow_dissector_key_ports *key_ports;
+	struct flow_dissector_key_icmp *key_icmp;
 	struct flow_dissector_key_tags *key_tags;
 	struct flow_dissector_key_vlan *key_vlan;
 	struct flow_dissector_key_keyid *key_keyid;
@@ -546,6 +569,14 @@ bool __skb_flow_dissect(const struct sk_buff *skb,
 							data, hlen);
 	}
 
+	if (dissector_uses_key(flow_dissector,
+			       FLOW_DISSECTOR_KEY_ICMP)) {
+		key_icmp = skb_flow_dissector_target(flow_dissector,
+						     FLOW_DISSECTOR_KEY_ICMP,
+						     target_container);
+		key_icmp->icmp = skb_flow_get_be16(skb, nhoff, data, hlen);
+	}
+
 out_good:
 	ret = true;
 
-- 
2.7.0.rc3.207.g0ac5344

[PATCH net-next v5 2/2] net/sched: cls_flower: Support matching on ICMP type and code

[Simon Horman]

Support matching on ICMP type and code.

Example usage:

tc qdisc add dev eth0 ingress

tc filter add dev eth0 protocol ip parent ffff: flower \
	indev eth0 ip_proto icmp type 8 code 0 action drop

tc filter add dev eth0 protocol ipv6 parent ffff: flower \
	indev eth0 ip_proto icmpv6 type 128 code 0 action drop

Signed-off-by: Simon Horman <simon.horman@netronome.com>
---
v5
* Open-code checking for icmp protocols rather than using helpers

v4
* No change

v3
* Use separate dissector key FLOW_DISSECTOR_KEY_ICMP
* Use separate structure to hold icmp fields, this does not share
  storage with ports

v2
* Move helpers to another patch
---
 include/uapi/linux/pkt_cls.h | 10 +++++++++
 net/sched/cls_flower.c       | 53 ++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 63 insertions(+)

diff --git a/include/uapi/linux/pkt_cls.h b/include/uapi/linux/pkt_cls.h
index 1adc0b654996..884c5aa515c4 100644
--- a/include/uapi/linux/pkt_cls.h
+++ b/include/uapi/linux/pkt_cls.h
@@ -458,6 +458,16 @@ enum {
 	TCA_FLOWER_KEY_ENC_UDP_SRC_PORT_MASK,	/* be16 */
 	TCA_FLOWER_KEY_ENC_UDP_DST_PORT,	/* be16 */
 	TCA_FLOWER_KEY_ENC_UDP_DST_PORT_MASK,	/* be16 */
+
+	TCA_FLOWER_KEY_ICMPV4_CODE,	/* u8 */
+	TCA_FLOWER_KEY_ICMPV4_CODE_MASK,/* u8 */
+	TCA_FLOWER_KEY_ICMPV4_TYPE,	/* u8 */
+	TCA_FLOWER_KEY_ICMPV4_TYPE_MASK,/* u8 */
+	TCA_FLOWER_KEY_ICMPV6_CODE,	/* u8 */
+	TCA_FLOWER_KEY_ICMPV6_CODE_MASK,/* u8 */
+	TCA_FLOWER_KEY_ICMPV6_TYPE,	/* u8 */
+	TCA_FLOWER_KEY_ICMPV6_TYPE_MASK,/* u8 */
+
 	__TCA_FLOWER_MAX,
 };
 
diff --git a/net/sched/cls_flower.c b/net/sched/cls_flower.c
index 29a9e6d9f274..f61f11b3194e 100644
--- a/net/sched/cls_flower.c
+++ b/net/sched/cls_flower.c
@@ -39,6 +39,7 @@ struct fl_flow_key {
 		struct flow_dissector_key_ipv6_addrs ipv6;
 	};
 	struct flow_dissector_key_ports tp;
+	struct flow_dissector_key_icmp icmp;
 	struct flow_dissector_key_keyid enc_key_id;
 	union {
 		struct flow_dissector_key_ipv4_addrs enc_ipv4;
@@ -386,6 +387,14 @@ static const struct nla_policy fl_policy[TCA_FLOWER_MAX + 1] = {
 	[TCA_FLOWER_KEY_ENC_UDP_SRC_PORT_MASK]	= { .type = NLA_U16 },
 	[TCA_FLOWER_KEY_ENC_UDP_DST_PORT]	= { .type = NLA_U16 },
 	[TCA_FLOWER_KEY_ENC_UDP_DST_PORT_MASK]	= { .type = NLA_U16 },
+	[TCA_FLOWER_KEY_ICMPV4_TYPE]	= { .type = NLA_U8 },
+	[TCA_FLOWER_KEY_ICMPV4_TYPE_MASK] = { .type = NLA_U8 },
+	[TCA_FLOWER_KEY_ICMPV4_CODE]	= { .type = NLA_U8 },
+	[TCA_FLOWER_KEY_ICMPV4_CODE_MASK] = { .type = NLA_U8 },
+	[TCA_FLOWER_KEY_ICMPV6_TYPE]	= { .type = NLA_U8 },
+	[TCA_FLOWER_KEY_ICMPV6_TYPE_MASK] = { .type = NLA_U8 },
+	[TCA_FLOWER_KEY_ICMPV6_CODE]	= { .type = NLA_U8 },
+	[TCA_FLOWER_KEY_ICMPV6_CODE_MASK] = { .type = NLA_U8 },
 };
 
 static void fl_set_key_val(struct nlattr **tb,
@@ -502,6 +511,26 @@ static int fl_set_key(struct net *net, struct nlattr **tb,
 		fl_set_key_val(tb, &key->tp.dst, TCA_FLOWER_KEY_SCTP_DST,
 			       &mask->tp.dst, TCA_FLOWER_KEY_SCTP_DST_MASK,
 			       sizeof(key->tp.dst));
+	} else if (key->basic.n_proto == htons(ETH_P_IP) &&
+		   key->basic.ip_proto == IPPROTO_ICMP) {
+		fl_set_key_val(tb, &key->icmp.type, TCA_FLOWER_KEY_ICMPV4_TYPE,
+			       &mask->icmp.type,
+			       TCA_FLOWER_KEY_ICMPV4_TYPE_MASK,
+			       sizeof(key->icmp.type));
+		fl_set_key_val(tb, &key->icmp.code, TCA_FLOWER_KEY_ICMPV4_CODE,
+			       &mask->icmp.code,
+			       TCA_FLOWER_KEY_ICMPV4_CODE_MASK,
+			       sizeof(key->icmp.code));
+	} else if (key->basic.n_proto == htons(ETH_P_IPV6) &&
+		   key->basic.ip_proto == IPPROTO_ICMPV6) {
+		fl_set_key_val(tb, &key->icmp.type, TCA_FLOWER_KEY_ICMPV6_TYPE,
+			       &mask->icmp.type,
+			       TCA_FLOWER_KEY_ICMPV6_TYPE_MASK,
+			       sizeof(key->icmp.type));
+		fl_set_key_val(tb, &key->icmp.code, TCA_FLOWER_KEY_ICMPV4_CODE,
+			       &mask->icmp.code,
+			       TCA_FLOWER_KEY_ICMPV4_CODE_MASK,
+			       sizeof(key->icmp.code));
 	}
 
 	if (tb[TCA_FLOWER_KEY_ENC_IPV4_SRC] ||
@@ -612,6 +641,8 @@ static void fl_init_dissector(struct cls_fl_head *head,
 	FL_KEY_SET_IF_MASKED(&mask->key, keys, cnt,
 			     FLOW_DISSECTOR_KEY_PORTS, tp);
 	FL_KEY_SET_IF_MASKED(&mask->key, keys, cnt,
+			     FLOW_DISSECTOR_KEY_ICMP, icmp);
+	FL_KEY_SET_IF_MASKED(&mask->key, keys, cnt,
 			     FLOW_DISSECTOR_KEY_VLAN, vlan);
 	FL_KEY_SET_IF_MASKED(&mask->key, keys, cnt,
 			     FLOW_DISSECTOR_KEY_ENC_KEYID, enc_key_id);
@@ -977,6 +1008,28 @@ static int fl_dump(struct net *net, struct tcf_proto *tp, unsigned long fh,
 				  &mask->tp.dst, TCA_FLOWER_KEY_SCTP_DST_MASK,
 				  sizeof(key->tp.dst))))
 		goto nla_put_failure;
+	else if (key->basic.n_proto == htons(ETH_P_IP) &&
+		 key->basic.ip_proto == IPPROTO_ICMP &&
+		 (fl_dump_key_val(skb, &key->icmp.type,
+				  TCA_FLOWER_KEY_ICMPV4_TYPE, &mask->icmp.type,
+				  TCA_FLOWER_KEY_ICMPV4_TYPE_MASK,
+				  sizeof(key->icmp.type)) ||
+		  fl_dump_key_val(skb, &key->icmp.code,
+				  TCA_FLOWER_KEY_ICMPV4_CODE, &mask->icmp.code,
+				  TCA_FLOWER_KEY_ICMPV4_CODE_MASK,
+				  sizeof(key->icmp.code))))
+		goto nla_put_failure;
+	else if (key->basic.n_proto == htons(ETH_P_IPV6) &&
+		 key->basic.ip_proto == IPPROTO_ICMPV6 &&
+		 (fl_dump_key_val(skb, &key->icmp.type,
+				  TCA_FLOWER_KEY_ICMPV6_TYPE, &mask->icmp.type,
+				  TCA_FLOWER_KEY_ICMPV6_TYPE_MASK,
+				  sizeof(key->icmp.type)) ||
+		  fl_dump_key_val(skb, &key->icmp.code,
+				  TCA_FLOWER_KEY_ICMPV6_CODE, &mask->icmp.code,
+				  TCA_FLOWER_KEY_ICMPV6_CODE_MASK,
+				  sizeof(key->icmp.code))))
+		goto nla_put_failure;
 
 	if (key->enc_control.addr_type == FLOW_DISSECTOR_KEY_IPV4_ADDRS &&
 	    (fl_dump_key_val(skb, &key->enc_ipv4.src,
-- 
2.7.0.rc3.207.g0ac5344

Re: [PATCH net-next v5 1/2] flow dissector: ICMP support

[Jiri Pirko]

Wed, Dec 07, 2016 at 01:14:39PM CET, simon.horman@netronome.com wrote:
>Allow dissection of ICMP(V6) type and code. This should only occur
>if a packet is ICMP(V6) and the dissector has FLOW_DISSECTOR_KEY_ICMP set.
>
>There are currently no users of FLOW_DISSECTOR_KEY_ICMP.
>A follow-up patch will allow FLOW_DISSECTOR_KEY_ICMP to be used by
>the flower classifier.


You are missing signedoff line.

Re: [PATCH net-next v5 1/2] flow dissector: ICMP support

[Simon Horman]

On Wed, Dec 07, 2016 at 01:26:29PM +0100, Jiri Pirko wrote:
> Wed, Dec 07, 2016 at 01:14:39PM CET, simon.horman@netronome.com wrote:
> >Allow dissection of ICMP(V6) type and code. This should only occur
> >if a packet is ICMP(V6) and the dissector has FLOW_DISSECTOR_KEY_ICMP set.
> >
> >There are currently no users of FLOW_DISSECTOR_KEY_ICMP.
> >A follow-up patch will allow FLOW_DISSECTOR_KEY_ICMP to be used by
> >the flower classifier.
> 
> 
> You are missing signedoff line.

Ooops!