From 8ff89c3926b9de73d88560bd36f5a2091c60cb94 Mon Sep 17 00:00:00 2001 From: djm Date: Thu, 3 Nov 2022 21:59:20 +0000 Subject: [PATCH] replace recently-added valid_domain() check for hostnames going to known_hosts with a more relaxed check for bad characters; previous commit broke address literals. Reported by/feedback from florian@ --- usr.bin/ssh/sshconnect.c | 20 ++++++++++++-------- 1 file changed, 12 insertions(+), 8 deletions(-) diff --git a/usr.bin/ssh/sshconnect.c b/usr.bin/ssh/sshconnect.c index cd4f0ccbcea..f5bdd35889b 100644 --- a/usr.bin/ssh/sshconnect.c +++ b/usr.bin/ssh/sshconnect.c @@ -1,4 +1,4 @@ -/* $OpenBSD: sshconnect.c,v 1.359 2022/10/24 22:43:36 djm Exp $ */ +/* $OpenBSD: sshconnect.c,v 1.360 2022/11/03 21:59:20 djm Exp $ */ /* * Author: Tatu Ylonen * Copyright (c) 1995 Tatu Ylonen , Espoo, Finland @@ -922,6 +922,17 @@ check_host_key(char *hostname, const struct ssh_conn_info *cinfo, return 0; } + /* + * Don't ever try to write an invalid name to a known hosts file. + * Note: do this before get_hostfile_hostname_ipaddr() to catch + * '[' or ']' in the name before they are added. + */ + if (strcspn(hostname, "@?*#[]|'\'\"\\") != strlen(hostname)) { + debug_f("invalid hostname \"%s\"; will not record: %s", + hostname, fail_reason); + readonly = RDONLY; + } + /* * Prepare the hostname and address strings used for hostkey lookup. * In some cases, these will have a port number appended. @@ -980,13 +991,6 @@ check_host_key(char *hostname, const struct ssh_conn_info *cinfo, (host_found != NULL && host_found->note != 0))) readonly = RDONLY; - /* Don't ever try to write an invalid name to a known hosts file */ - if (!valid_domain(hostname, 0, &fail_reason)) { - debug_f("invalid hostname \"%s\"; will not record: %s", - hostname, fail_reason); - readonly = RDONLY; - } - /* * Also perform check for the ip address, skip the check if we are * localhost, looking for a certificate, or the hostname was an ip -- 2.20.1