upstream commit

don't accept junk after "yes" or "no" responses to
hostkey prompts. bz#2803 reported by Maksim Derbasov; ok dtucker@

OpenBSD-Commit-ID: e1b159fb2253be973ce25eb7a7be26e6f967717c

1 files changed, 6 insertions, 5 deletions

diff --git a/sshconnect.c b/sshconnect.c
index e29b069c9..44977707d 100644
--- a/sshconnect.c
+++ b/sshconnect.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: sshconnect.c,v 1.288 2017/11/25 06:46:22 dtucker Exp $ */
+/* $OpenBSD: sshconnect.c,v 1.289 2017/12/06 05:06:21 djm Exp $ */
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -631,11 +631,12 @@ confirm(const char *prompt)
                 return 0;
         for (msg = prompt;;msg = again) {
                 p = read_passphrase(msg, RP_ECHO);
-                if (p == NULL ||
-                    (p[0] == '\0') || (p[0] == '\n') ||
-                    strncasecmp(p, "no", 2) == 0)
+                if (p == NULL)
+                        return 0;
+                p[strcspn(p, "\n")] = '\0';
+                if (p[0] == '\0' || strcasecmp(p, "no") == 0)
                         ret = 0;
-                if (p && strncasecmp(p, "yes", 3) == 0)
+                else if (strcasecmp(p, "yes") == 0)
                         ret = 1;
                 free(p);
                 if (ret != -1)