From dda2fa08a13c688bed320ef2e4ba541abb4d6c17 Mon Sep 17 00:00:00 2001 From: Wojciech Drewek Date: Thu, 8 Sep 2022 10:16:41 -0700 Subject: flow_dissector: Add L2TPv3 dissectors Allow to dissect L2TPv3 specific field which is: - session ID (32 bits) L2TPv3 might be transported over IP or over UDP, this implementation is only about L2TPv3 over IP. IP protocol carries L2TPv3 when ip_proto is IPPROTO_L2TP (115). Acked-by: Guillaume Nault Signed-off-by: Wojciech Drewek Signed-off-by: Tony Nguyen Signed-off-by: Paolo Abeni --- net/core/flow_dissector.c | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+) (limited to 'net/core') diff --git a/net/core/flow_dissector.c b/net/core/flow_dissector.c index 990429c69ccd..2a1f513a2dc8 100644 --- a/net/core/flow_dissector.c +++ b/net/core/flow_dissector.c @@ -204,6 +204,30 @@ static void __skb_flow_dissect_icmp(const struct sk_buff *skb, skb_flow_get_icmp_tci(skb, key_icmp, data, thoff, hlen); } +static void __skb_flow_dissect_l2tpv3(const struct sk_buff *skb, + struct flow_dissector *flow_dissector, + void *target_container, const void *data, + int nhoff, int hlen) +{ + struct flow_dissector_key_l2tpv3 *key_l2tpv3; + struct { + __be32 session_id; + } *hdr, _hdr; + + if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_L2TPV3)) + return; + + hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen, &_hdr); + if (!hdr) + return; + + key_l2tpv3 = skb_flow_dissector_target(flow_dissector, + FLOW_DISSECTOR_KEY_L2TPV3, + target_container); + + key_l2tpv3->session_id = hdr->session_id; +} + void skb_flow_dissect_meta(const struct sk_buff *skb, struct flow_dissector *flow_dissector, void *target_container) @@ -1501,6 +1525,10 @@ ip_proto_again: __skb_flow_dissect_icmp(skb, flow_dissector, target_container, data, nhoff, hlen); break; + case IPPROTO_L2TP: + __skb_flow_dissect_l2tpv3(skb, flow_dissector, target_container, + data, nhoff, hlen); + break; default: break; -- cgit v1.2.3-59-g8ed1b