flow_dissector: Move MPLS dissection into a separate function

Make the main flow_dissect function a bit smaller and move the MPLS
dissection into a separate function. Along with that, do the MPLS header
processing only in case the flow dissection user requires it.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Jiri Pirko 2017-03-06 16:39:52 +01:00 committed by David S. Miller
parent 9bf881ffc5
commit 4a5d6c8b14
1 changed files with 34 additions and 22 deletions

View File

@ -118,6 +118,33 @@ enum flow_dissect_ret {
FLOW_DISSECT_RET_OUT_BAD,
};
static enum flow_dissect_ret
__skb_flow_dissect_mpls(const struct sk_buff *skb,
struct flow_dissector *flow_dissector,
void *target_container, void *data, int nhoff, int hlen)
{
struct flow_dissector_key_keyid *key_keyid;
struct mpls_label *hdr, _hdr[2];
if (!dissector_uses_key(flow_dissector,
FLOW_DISSECTOR_KEY_MPLS_ENTROPY))
return FLOW_DISSECT_RET_OUT_GOOD;
hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data,
hlen, &_hdr);
if (!hdr)
return FLOW_DISSECT_RET_OUT_BAD;
if ((ntohl(hdr[0].entry) & MPLS_LS_LABEL_MASK) >>
MPLS_LS_LABEL_SHIFT == MPLS_LABEL_ENTROPY) {
key_keyid = skb_flow_dissector_target(flow_dissector,
FLOW_DISSECTOR_KEY_MPLS_ENTROPY,
target_container);
key_keyid->keyid = hdr[1].entry & htonl(MPLS_LS_LABEL_MASK);
}
return FLOW_DISSECT_RET_OUT_GOOD;
}
static enum flow_dissect_ret
__skb_flow_dissect_arp(const struct sk_buff *skb,
struct flow_dissector *flow_dissector,
@ -408,31 +435,16 @@ bool __skb_flow_dissect(const struct sk_buff *skb,
}
case htons(ETH_P_MPLS_UC):
case htons(ETH_P_MPLS_MC): {
struct mpls_label *hdr, _hdr[2];
case htons(ETH_P_MPLS_MC):
mpls:
hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data,
hlen, &_hdr);
if (!hdr)
goto out_bad;
if ((ntohl(hdr[0].entry) & MPLS_LS_LABEL_MASK) >>
MPLS_LS_LABEL_SHIFT == MPLS_LABEL_ENTROPY) {
if (dissector_uses_key(flow_dissector,
FLOW_DISSECTOR_KEY_MPLS_ENTROPY)) {
key_keyid = skb_flow_dissector_target(flow_dissector,
FLOW_DISSECTOR_KEY_MPLS_ENTROPY,
target_container);
key_keyid->keyid = hdr[1].entry &
htonl(MPLS_LS_LABEL_MASK);
}
switch (__skb_flow_dissect_mpls(skb, flow_dissector,
target_container, data,
nhoff, hlen)) {
case FLOW_DISSECT_RET_OUT_GOOD:
goto out_good;
case FLOW_DISSECT_RET_OUT_BAD:
goto out_bad;
}
goto out_good;
}
case htons(ETH_P_FCOE):
if ((hlen - nhoff) < FCOE_HEADER_LEN)
goto out_bad;