From fcd135c9df440bcd2d5870405ad3311743d78d97 Mon Sep 17 00:00:00 2001 From: "dtucker@openbsd.org" Date: Thu, 21 Jul 2016 01:39:35 +0000 Subject: upstream commit Skip passwords longer than 1k in length so clients can't easily DoS sshd by sending very long passwords, causing it to spend CPU hashing them. feedback djm@, ok markus@. Brought to our attention by tomas.kuthan at oracle.com, shilei-c at 360.cn and coredump at autistici.org Upstream-ID: d0af7d4a2190b63ba1d38eec502bc4be0be9e333 --- auth-passwd.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) (limited to 'auth-passwd.c') diff --git a/auth-passwd.c b/auth-passwd.c index 530b5d4f..996c2cf7 100644 --- a/auth-passwd.c +++ b/auth-passwd.c @@ -1,4 +1,4 @@ -/* $OpenBSD: auth-passwd.c,v 1.44 2014/07/15 15:54:14 millert Exp $ */ +/* $OpenBSD: auth-passwd.c,v 1.45 2016/07/21 01:39:35 dtucker Exp $ */ /* * Author: Tatu Ylonen * Copyright (c) 1995 Tatu Ylonen , Espoo, Finland @@ -66,6 +66,8 @@ extern login_cap_t *lc; #define DAY (24L * 60 * 60) /* 1 day in seconds */ #define TWO_WEEKS (2L * 7 * DAY) /* 2 weeks in seconds */ +#define MAX_PASSWORD_LEN 1024 + void disable_forwarding(void) { @@ -87,6 +89,9 @@ auth_password(Authctxt *authctxt, const char *password) static int expire_checked = 0; #endif + if (strlen(password) > MAX_PASSWORD_LEN) + return 0; + #ifndef HAVE_CYGWIN if (pw->pw_uid == 0 && options.permit_root_login != PERMIT_YES) ok = 0; -- cgit v1.2.1