diff options
| author | Matteo Croce <mcroce@redhat.com> | 2019-10-29 14:50:51 +0100 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2019-10-30 17:21:35 -0700 |
| commit | 3b336d6f4ec690b0082bcffe55bac22f234a41ff (patch) | |
| tree | bedc154ea4528ee99b1376f57007747cbec05190 /net | |
| parent | 98298e6ca6d5908f96e529e70a254a4d5bf754e7 (diff) | |
| download | linux-3b336d6f4ec690b0082bcffe55bac22f234a41ff.tar.bz2 | |
flow_dissector: skip the ICMP dissector for non ICMP packets
FLOW_DISSECTOR_KEY_ICMP is checked for every packet, not only ICMP ones.
Even if the test overhead is probably negligible, move the
ICMP dissector code under the big 'switch(ip_proto)' so it gets called
only for ICMP packets.
Signed-off-by: Matteo Croce <mcroce@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net')
| -rw-r--r-- | net/core/flow_dissector.c | 34 |
1 files changed, 25 insertions, 9 deletions
diff --git a/net/core/flow_dissector.c b/net/core/flow_dissector.c index bc22b384ac6c..0fb721976f3d 100644 --- a/net/core/flow_dissector.c +++ b/net/core/flow_dissector.c @@ -234,6 +234,25 @@ __be32 __skb_flow_get_ports(const struct sk_buff *skb, int thoff, u8 ip_proto, } EXPORT_SYMBOL(__skb_flow_get_ports); +/* If FLOW_DISSECTOR_KEY_ICMP is set, get the Type and Code from an ICMP packet + * using skb_flow_get_be16(). + */ +static void __skb_flow_dissect_icmp(const struct sk_buff *skb, + struct flow_dissector *flow_dissector, + void *target_container, + void *data, int thoff, int hlen) +{ + struct flow_dissector_key_icmp *key_icmp; + + if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ICMP)) + return; + + key_icmp = skb_flow_dissector_target(flow_dissector, + FLOW_DISSECTOR_KEY_ICMP, + target_container); + key_icmp->icmp = skb_flow_get_be16(skb, thoff, data, hlen); +} + void skb_flow_dissect_meta(const struct sk_buff *skb, struct flow_dissector *flow_dissector, void *target_container) @@ -884,7 +903,6 @@ bool __skb_flow_dissect(const struct net *net, 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 bpf_prog *attached = NULL; @@ -1329,6 +1347,12 @@ ip_proto_again: data, nhoff, hlen); break; + case IPPROTO_ICMP: + case IPPROTO_ICMPV6: + __skb_flow_dissect_icmp(skb, flow_dissector, target_container, + data, nhoff, hlen); + break; + default: break; } @@ -1342,14 +1366,6 @@ 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); - } - /* Process result of IP proto processing */ switch (fdret) { case FLOW_DISSECT_RET_PROTO_AGAIN: |