From 1d712c05370dca8cbf81d1ecd9acd606fdcacaf4 Mon Sep 17 00:00:00 2001 From: Zhenlei Huang Date: Mon, 3 May 2021 12:46:19 -0400 Subject: [PATCH] traceroute6: Properly calculate UDP checksum The revision D25604 capsicumize traceroute6. For UDP the send socket was changed from SOCK_DGRAM to SOCK_RAW and thus the UDP checksum need be calculated by application itself other than the kernel. outpacket is filled with zeros by line 707, thus the first round the UDP checksum is correct. But subsequent rounds outudp->uh_sum will be left with garbage. PR: 255507 Reviewed by: ae, markj, tuexen MFC after: 3 days Differential Revision: https://reviews.freebsd.org/D30042 --- usr.sbin/traceroute6/traceroute6.c | 1 + 1 file changed, 1 insertion(+) diff --git a/usr.sbin/traceroute6/traceroute6.c b/usr.sbin/traceroute6/traceroute6.c index 8449a9861302..a071c084ad07 100644 --- a/usr.sbin/traceroute6/traceroute6.c +++ b/usr.sbin/traceroute6/traceroute6.c @@ -1118,6 +1118,7 @@ send_probe(int seq, u_long hops) outudp->uh_sport = htons(ident); outudp->uh_dport = htons(port+seq); outudp->uh_ulen = htons(datalen); + outudp->uh_sum = 0; outudp->uh_sum = udp_cksum(&Src, &Dst, outpacket, datalen); break; case IPPROTO_NONE: