flow dissector: ICMP support

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.

Signed-off-by: Simon Horman <simon.horman@netronome.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Simon Horman 2016-12-07 13:48:27 +01:00 committed by David S. Miller
parent 7cc99fd29b
commit 972d3876fa
2 changed files with 48 additions and 0 deletions

View File

@ -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 */

View File

@ -57,6 +57,28 @@ 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
@ -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 @@ ip_proto_again:
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;