diff options
| author |   naddy <naddy@openbsd.org> | 2014-01-26 18:03:27 +0000 |
|---|---|---|
| committer | naddy <naddy@openbsd.org> | 2014-01-26 18:03:27 +0000 |
| commit | 2961f03a094ea49186bb3177a004910e89f9ef5d (patch) | |
| tree | 05b71961184b011be93bf55a4404805ad4488258 /usr.sbin/tcpdump/print-udp.c | |
| parent | Attempt to make user changes of keyboard layout a bit more `sticky' on wsmux (diff) | |
| download | wireguard-openbsd-2961f03a094ea49186bb3177a004910e89f9ef5d.tar.xz wireguard-openbsd-2961f03a094ea49186bb3177a004910e89f9ef5d.zip | |
show that zero checksums are invalid for UDP over IPv6; input & ok bluhm@
Diffstat (limited to 'usr.sbin/tcpdump/print-udp.c')
| -rw-r--r-- | usr.sbin/tcpdump/print-udp.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/usr.sbin/tcpdump/print-udp.c b/usr.sbin/tcpdump/print-udp.c index 4ddfbdeb732..f1ecd7a83ef 100644 --- a/usr.sbin/tcpdump/print-udp.c +++ b/usr.sbin/tcpdump/print-udp.c @@ -1,4 +1,4 @@ -/* $OpenBSD: print-udp.c,v 1.34 2010/01/12 06:10:33 naddy Exp $ */ +/* $OpenBSD: print-udp.c,v 1.35 2014/01/26 18:03:27 naddy Exp $ */ /* * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996 @@ -581,7 +581,9 @@ udp_print(register const u_char *bp, u_int length, register const u_char *bp2) if (ip->ip_v == 6 && ip6->ip6_plen && vflag) { int sum = up->uh_sum; /* for IPv6, UDP checksum is mandatory */ - if (TTEST2(cp[0], length)) { + if (sum == 0) { + (void)printf(" [invalid cksum 0]"); + } else if (TTEST2(cp[0], length)) { sum = udp6_cksum(ip6, up, length + sizeof(struct udphdr)); if (sum != 0) (void)printf(" [bad udp cksum %x!]", sum); |