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 <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/flow_dissector.h b/include/net/flow_dissector.h
index 74fe160..3410227 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 @@
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 c3d9807..7536a46 100644
--- a/net/core/flow_dissector.c
+++ b/net/core/flow_dissector.c
@@ -177,8 +177,6 @@
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 @@
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): {