From 807e165dc44fd93f9d378f861f0540a158d7343a Mon Sep 17 00:00:00 2001 From: Tom Herbert Date: Tue, 1 Sep 2015 09:24:28 -0700 Subject: [PATCH] flow_dissector: Add control/reporting of fragmentation Add an input flag to flow dissector on rather dissection should be attempted on a first fragment. Also add key_control flags to indicate that a packet is a fragment or first fragment. Signed-off-by: Tom Herbert Signed-off-by: David S. Miller --- include/net/flow_dissector.h | 4 ++++ net/core/flow_dissector.c | 15 +++++++++++++-- 2 files changed, 17 insertions(+), 2 deletions(-) diff --git a/include/net/flow_dissector.h b/include/net/flow_dissector.h index 74fe160f0b05..34102270b086 100644 --- a/include/net/flow_dissector.h +++ b/include/net/flow_dissector.h @@ -12,6 +12,8 @@ struct flow_dissector_key_control { u16 thoff; u16 addr_type; + u32 is_fragment:1; + u32 first_frag:1; }; /** @@ -122,6 +124,8 @@ enum flow_dissector_key_id { FLOW_DISSECTOR_KEY_MAX, }; +#define FLOW_DISSECTOR_F_PARSE_1ST_FRAG BIT(0) + struct flow_dissector_key { enum flow_dissector_key_id key_id; size_t offset; /* offset of struct flow_dissector_key_* diff --git a/net/core/flow_dissector.c b/net/core/flow_dissector.c index c3d9807cb34e..7536a4669029 100644 --- a/net/core/flow_dissector.c +++ b/net/core/flow_dissector.c @@ -177,8 +177,6 @@ bool __skb_flow_dissect(const struct sk_buff *skb, nhoff += iph->ihl * 4; ip_proto = iph->protocol; - if (ip_is_fragment(iph)) - ip_proto = 0; if (!skb_flow_dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_IPV4_ADDRS)) @@ -189,6 +187,19 @@ bool __skb_flow_dissect(const struct sk_buff *skb, memcpy(&key_addrs->v4addrs, &iph->saddr, sizeof(key_addrs->v4addrs)); key_control->addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS; + + if (ip_is_fragment(iph)) { + key_control->is_fragment = 1; + + if (iph->frag_off & htons(IP_OFFSET)) { + goto out_good; + } else { + key_control->first_frag = 1; + if (!(flags & FLOW_DISSECTOR_F_PARSE_1ST_FRAG)) + goto out_good; + } + } + break; } case htons(ETH_P_IPV6): {