From fcdaa8a9b39fa4001d05d81064acab27098241df Mon Sep 17 00:00:00 2001 From: Toke Høiland-Jørgensen Date: Wed, 29 Apr 2020 14:59:22 -0600 Subject: wireguard: receive: use tunnel helpers for decapsulating ECN markings MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit commit e8c72696cd7e7bc6abd0be69ce2abea476685e37 upstream. WireGuard currently only propagates ECN markings on tunnel decap according to the old RFC3168 specification. However, the spec has since been updated in RFC6040 to recommend slightly different decapsulation semantics. This was implemented in the kernel as a set of common helpers for ECN decapsulation, so let's just switch over WireGuard to using those, so it can benefit from this enhancement and any future tweaks. We do not drop packets with invalid ECN marking combinations, because WireGuard is frequently used to work around broken ISPs, which could be doing that. Fixes: a8f1bc7bdea3 ("net: WireGuard secure network tunnel") Reported-by: Olivier Tilmans Cc: Dave Taht Cc: Rodney W. Grimes Signed-off-by: Toke Høiland-Jørgensen Signed-off-by: Jason A. Donenfeld Signed-off-by: David S. Miller Signed-off-by: Jason A. Donenfeld --- drivers/net/wireguard/receive.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/drivers/net/wireguard/receive.c b/drivers/net/wireguard/receive.c index da3b782..267f202 100644 --- a/drivers/net/wireguard/receive.c +++ b/drivers/net/wireguard/receive.c @@ -393,13 +393,11 @@ static void wg_packet_consume_data_done(struct wg_peer *peer, len = ntohs(ip_hdr(skb)->tot_len); if (unlikely(len < sizeof(struct iphdr))) goto dishonest_packet_size; - if (INET_ECN_is_ce(PACKET_CB(skb)->ds)) - IP_ECN_set_ce(ip_hdr(skb)); + INET_ECN_decapsulate(skb, PACKET_CB(skb)->ds, ip_hdr(skb)->tos); } else if (skb->protocol == htons(ETH_P_IPV6)) { len = ntohs(ipv6_hdr(skb)->payload_len) + sizeof(struct ipv6hdr); - if (INET_ECN_is_ce(PACKET_CB(skb)->ds)) - IP6_ECN_set_ce(skb, ipv6_hdr(skb)); + INET_ECN_decapsulate(skb, PACKET_CB(skb)->ds, ipv6_get_dsfield(ipv6_hdr(skb))); } else { goto dishonest_packet_type; } -- cgit v1.2.3