From mboxrd@z Thu Jan  1 00:00:00 1970
From: Erik Kapfer <erik.kapfer@ipfire.org>
To: development@lists.ipfire.org
Subject: [PATCH] OpenVPN: Fix for '--ns-cert-type server is deprecated' .
Date: Fri, 06 Oct 2017 15:14:48 +0200
Message-ID: <1507295688-7140-1-git-send-email-erik.kapfer@ipfire.org>
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- Added extended key usage based on RFC3280 TLS rules for OpenVPNs OpenSSL co=
nfiguration,
so '--remote-cert-tls' can be used instead of the old and deprecated '--ns-ce=
rt-type'
if the host certificate are newely generated with this options.
Nevertheless both directives (old and new) will work also with old CAs.

- Automatic detection if the host certificate uses the new options.
If it does, '--remote-cert-tls server' will be automatically set into the cli=
ent
configuration files for Net-to-Net and Roadwarriors connections.

If it does NOT, the old '--ns-cert-type server' directive will be set in the =
client
configuration file.
---
 config/ovpn/openssl/ovpn.cnf |  4 ++++
 html/cgi-bin/ovpnmain.cgi    | 31 +++++++++++++++++++++++++++----
 2 files changed, 31 insertions(+), 4 deletions(-)

diff --git a/config/ovpn/openssl/ovpn.cnf b/config/ovpn/openssl/ovpn.cnf
index ab026c1..40daf2a 100644
--- a/config/ovpn/openssl/ovpn.cnf
+++ b/config/ovpn/openssl/ovpn.cnf
@@ -77,6 +77,8 @@ basicConstraints		=3D CA:FALSE
 nsComment			=3D "OpenSSL Generated Certificate"
 subjectKeyIdentifier		=3D hash
 authorityKeyIdentifier		=3D keyid,issuer:always
+extendedKeyUsage               =3D clientAuth
+keyUsage                       =3D digitalSignature
=20
 [ server ]
=20
@@ -86,6 +88,8 @@ nsCertType			=3D server
 nsComment			=3D "OpenSSL Generated Server Certificate"
 subjectKeyIdentifier		=3D hash
 authorityKeyIdentifier		=3D keyid,issuer:always=20
+extendedKeyUsage               =3D serverAuth
+keyUsage                       =3D digitalSignature, keyEncipherment
=20
 [ v3_req ]
 basicConstraints 		=3D CA:FALSE
diff --git a/html/cgi-bin/ovpnmain.cgi b/html/cgi-bin/ovpnmain.cgi
index d46a14e..ceb88c1 100644
--- a/html/cgi-bin/ovpnmain.cgi
+++ b/html/cgi-bin/ovpnmain.cgi
@@ -1061,8 +1061,15 @@ unless(-d "${General::swroot}/ovpn/n2nconf/$cgiparams{=
'NAME'}"){mkdir "${General
 		}
         }
   }
-=20
-  print CLIENTCONF "ns-cert-type server\n";  =20
+  # Check host certificate if X509 is RFC3280 compliant.
+  # If not, old --ns-cert-type directive will be used.
+  # If appropriate key usage extension exists, new --remote-cert-tls directi=
ve will be used.
+  my $hostcert =3D `/usr/bin/openssl x509 -text -in ${General::swroot}/ovpn/=
certs/servercert.pem`;
+  if ($hostcert !~ /TLS Web Server Authentication/) {
+       print CLIENTCONF "ns-cert-type server\n";
+  } else {
+       print CLIENTCONF "remote-cert-tls server\n";
+  }
   print CLIENTCONF "# Auth. Client\n";=20
   print CLIENTCONF "tls-client\n";=20
   print CLIENTCONF "# Cipher\n";=20
@@ -2173,7 +2180,15 @@ if ($confighash{$cgiparams{'KEY'}}[3] eq 'net'){
 		}
 	}
    }
-   print CLIENTCONF "ns-cert-type server\n";  =20
+   # Check host certificate if X509 is RFC3280 compliant.
+   # If not, old --ns-cert-type directive will be used.
+   # If appropriate key usage extension exists, new --remote-cert-tls direct=
ive will be used.
+   my $hostcert =3D `/usr/bin/openssl x509 -text -in ${General::swroot}/ovpn=
/certs/servercert.pem`;
+   if ($hostcert !~ /TLS Web Server Authentication/) {
+               print CLIENTCONF "ns-cert-type server\n";
+   } else {
+               print CLIENTCONF "remote-cert-tls server\n";
+   }
    print CLIENTCONF "# Auth. Client\n";=20
    print CLIENTCONF "tls-client\n";=20
    print CLIENTCONF "# Cipher\n";
@@ -2332,7 +2347,15 @@ else
         print CLIENTCONF "comp-lzo\r\n";
     }
     print CLIENTCONF "verb 3\r\n";
-    print CLIENTCONF "ns-cert-type server\r\n";
+	# Check host certificate if X509 is RFC3280 compliant.
+	# If not, old --ns-cert-type directive will be used.
+	# If appropriate key usage extension exists, new --remote-cert-tls directiv=
e will be used.
+	my $hostcert =3D `/usr/bin/openssl x509 -text -in ${General::swroot}/ovpn/c=
erts/servercert.pem`;
+	if ($hostcert !~ /TLS Web Server Authentication/) {
+		print CLIENTCONF "ns-cert-type server\r\n";
+	} else {
+		print CLIENTCONF "remote-cert-tls server\r\n";
+	}
     print CLIENTCONF "verify-x509-name $vpnsettings{ROOTCERT_HOSTNAME} name\=
r\n";
     if ($vpnsettings{MSSFIX} eq 'on') {
 	print CLIENTCONF "mssfix\r\n";
--=20
2.7.4


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