From 30ac73bcc2b2fa7b997cb572e5b03ea9107b7641 Mon Sep 17 00:00:00 2001 From: Darren Tucker Date: Fri, 13 Jun 2008 04:46:45 +1000 Subject: - dtucker@cvs.openbsd.org 2008/06/12 00:03:49 [dns.c canohost.c sshconnect.c] Do not pass "0" strings as ports to getaddrinfo because the lookups can slow things down and we never use the service info anyway. bz #859, patch from YOSHIFUJI Hideaki and John Devitofranceschi. ok deraadt@ djm@ djm belives that the reason for the "0" strings is to ensure that it's not possible to call getaddrinfo with both host and port being NULL. In the case of canohost.c host is a local array. In the case of sshconnect.c, it's checked for null immediately before use. In dns.c it ultimately comes from ssh.c:main() and is guaranteed to be non-null but it's not obvious, so I added a warning message in case it is ever passed a null. --- dns.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) (limited to 'dns.c') diff --git a/dns.c b/dns.c index a89176f8..a7da03fa 100644 --- a/dns.c +++ b/dns.c @@ -1,4 +1,4 @@ -/* $OpenBSD: dns.c,v 1.24 2007/01/03 03:01:40 stevesk Exp $ */ +/* $OpenBSD: dns.c,v 1.25 2008/06/12 00:03:49 dtucker Exp $ */ /* * Copyright (c) 2003 Wesley Griffin. All rights reserved. @@ -145,11 +145,20 @@ is_numeric_hostname(const char *hostname) { struct addrinfo hints, *ai; + /* + * We shouldn't ever get a null host but if we do then log an error + * and return -1 which stops DNS key fingerprint processing. + */ + if (hostname == NULL) { + error("is_numeric_hostname called with NULL hostname"); + return -1; + } + memset(&hints, 0, sizeof(hints)); hints.ai_socktype = SOCK_DGRAM; hints.ai_flags = AI_NUMERICHOST; - if (getaddrinfo(hostname, "0", &hints, &ai) == 0) { + if (getaddrinfo(hostname, NULL, &hints, &ai) == 0) { freeaddrinfo(ai); return -1; } -- cgit v1.2.3