From 4a5d6c8b14b81e3704607a354434321e390d228a Mon Sep 17 00:00:00 2001 From: Jiri Pirko Date: Mon, 6 Mar 2017 16:39:52 +0100 Subject: [PATCH] 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 Signed-off-by: David S. Miller --- net/core/flow_dissector.c | 56 ++++++++++++++++++++++++--------------- 1 file changed, 34 insertions(+), 22 deletions(-) diff --git a/net/core/flow_dissector.c b/net/core/flow_dissector.c index d79fb8f8f033..8d012987e3c3 100644 --- a/net/core/flow_dissector.c +++ b/net/core/flow_dissector.c @@ -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 @@ ipv6: } 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; -- 2.20.1