diff --git a/ChangeLog b/ChangeLog
index bcca919b4..8ade4e7ea 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -4,6 +4,8 @@
    cleanup functions.  With & ok djm@
  - (dtucker) [contrib/redhat/openssh.spec] Bug #714: Now that UsePAM is a
    run-time switch, always build --with-md5-passwords.
+ - (dtucker) [configure.ac openbsd-compat/Makefile.in openbsd-compat/strtoul.c]
+   Bug #670: add strtoul() to openbsd-compat for platforms lacking it.  ok djm@
 
 20031003
  - (dtucker) OpenBSD CVS Sync
@@ -1286,4 +1288,4 @@
  - Fix sshd BindAddress and -b options for systems using fake-getaddrinfo.
    Report from murple@murple.net, diagnosis from dtucker@zip.com.au
 
-$Id: ChangeLog,v 1.3060 2003/10/07 07:40:56 dtucker Exp $
+$Id: ChangeLog,v 1.3061 2003/10/07 07:49:56 dtucker Exp $
diff --git a/configure.ac b/configure.ac
index dd22c98d4..02b7e2b82 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1,4 +1,4 @@
-# $Id: configure.ac,v 1.169 2003/10/02 06:26:34 dtucker Exp $
+# $Id: configure.ac,v 1.170 2003/10/07 07:49:57 dtucker Exp $
 
 AC_INIT
 AC_CONFIG_SRCDIR([ssh.c])
@@ -739,7 +739,7 @@ AC_CHECK_FUNCS(\
 	setdtablesize setegid setenv seteuid setgroups setlogin setpcred \
 	setproctitle setregid setresgid setresuid setreuid setrlimit \
 	setsid setvbuf sigaction sigvec snprintf socketpair strerror \
-	strlcat strlcpy strmode strnvis sysconf tcgetpgrp \
+	strlcat strlcpy strmode strnvis strtoul sysconf tcgetpgrp \
 	truncate utimes vhangup vsnprintf waitpid \
 )
 
diff --git a/openbsd-compat/Makefile.in b/openbsd-compat/Makefile.in
index c48593f7b..de9856eea 100644
--- a/openbsd-compat/Makefile.in
+++ b/openbsd-compat/Makefile.in
@@ -1,4 +1,4 @@
-# $Id: Makefile.in,v 1.28 2003/07/24 06:52:14 mouring Exp $
+# $Id: Makefile.in,v 1.29 2003/10/07 07:49:57 dtucker Exp $
 
 sysconfdir=@sysconfdir@
 piddir=@piddir@
@@ -16,7 +16,7 @@ RANLIB=@RANLIB@
 INSTALL=@INSTALL@
 LDFLAGS=-L. @LDFLAGS@
 
-OPENBSD=base64.o basename.o bindresvport.o daemon.o dirname.o getcwd.o getgrouplist.o getopt.o getrrsetbyname.o glob.o inet_aton.o inet_ntoa.o inet_ntop.o mktemp.o readpassphrase.o realpath.o rresvport.o setenv.o setproctitle.o sigact.o strlcat.o strlcpy.o strmode.o strsep.o vis.o
+OPENBSD=base64.o basename.o bindresvport.o daemon.o dirname.o getcwd.o getgrouplist.o getopt.o getrrsetbyname.o glob.o inet_aton.o inet_ntoa.o inet_ntop.o mktemp.o readpassphrase.o realpath.o rresvport.o setenv.o setproctitle.o sigact.o strlcat.o strlcpy.o strmode.o strsep.o strtoul.o vis.o
 
 COMPAT=bsd-arc4random.o bsd-cray.o bsd-cygwin_util.o bsd-getpeereid.o bsd-misc.o bsd-nextstep.o bsd-snprintf.o bsd-waitpid.o fake-rfc2553.o xmmap.o xcrypt.o
 
diff --git a/openbsd-compat/strtoul.c b/openbsd-compat/strtoul.c
new file mode 100644
index 000000000..877e6a01f
--- /dev/null
+++ b/openbsd-compat/strtoul.c
@@ -0,0 +1,112 @@
+/*
+ * Copyright (c) 1990 Regents of the University of California.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include "includes.h"
+#ifndef HAVE_STRTOUL
+
+#if defined(LIBC_SCCS) && !defined(lint)
+static char *rcsid = "$OpenBSD: strtoul.c,v 1.5 2003/06/02 20:18:38 millert Exp $";
+#endif /* LIBC_SCCS and not lint */
+
+#include <ctype.h>
+#include <errno.h>
+#include <limits.h>
+#include <stdlib.h>
+
+/*
+ * Convert a string to an unsigned long integer.
+ *
+ * Ignores `locale' stuff.  Assumes that the upper and lower case
+ * alphabets and digits are each contiguous.
+ */
+unsigned long
+strtoul(nptr, endptr, base)
+	const char *nptr;
+	char **endptr;
+	register int base;
+{
+	register const char *s;
+	register unsigned long acc, cutoff;
+	register int c;
+	register int neg, any, cutlim;
+
+	/*
+	 * See strtol for comments as to the logic used.
+	 */
+	s = nptr;
+	do {
+		c = (unsigned char) *s++;
+	} while (isspace(c));
+	if (c == '-') {
+		neg = 1;
+		c = *s++;
+	} else {
+		neg = 0;
+		if (c == '+')
+			c = *s++;
+	}
+	if ((base == 0 || base == 16) &&
+	    c == '0' && (*s == 'x' || *s == 'X')) {
+		c = s[1];
+		s += 2;
+		base = 16;
+	}
+	if (base == 0)
+		base = c == '0' ? 8 : 10;
+
+	cutoff = ULONG_MAX / (unsigned long)base;
+	cutlim = ULONG_MAX % (unsigned long)base;
+	for (acc = 0, any = 0;; c = (unsigned char) *s++) {
+		if (isdigit(c))
+			c -= '0';
+		else if (isalpha(c))
+			c -= isupper(c) ? 'A' - 10 : 'a' - 10;
+		else
+			break;
+		if (c >= base)
+			break;
+		if (any < 0)
+			continue;
+		if (acc > cutoff || acc == cutoff && c > cutlim) {
+			any = -1;
+			acc = ULONG_MAX;
+			errno = ERANGE;
+		} else {
+			any = 1;
+			acc *= (unsigned long)base;
+			acc += c;
+		}
+	}
+	if (neg && any > 0)
+		acc = -acc;
+	if (endptr != 0)
+		*endptr = (char *) (any ? s - 1 : nptr);
+	return (acc);
+}
+#endif /* !HAVE_STRTOUL */