openvpn: enable using wolfSSL cryptographic API engine

Support for wolfSSL has been upstreamed to the master OpenVPN branch
in f6dca235ae560597a0763f0c98fcc9130b80ccf4 so we can use wolfSSL
directly in OpenVPN. So no more needed differnt SSL engine for OpenVPN
in systems based on wolfSSL library
Compiled && tested on ramips/mt7620, ramips/mt7621

Signed-off-by: Ivan Pavlov <AuthorReflex@gmail.com>

5 files changed, 265 insertions, 2 deletions

diff --git a/net/openvpn/Config-wolfssl.in b/net/openvpn/Config-wolfssl.in
new file mode 100644
index 000000000..ef8b9dcb3
--- /dev/null
+++ b/net/openvpn/Config-wolfssl.in
@@ -0,0 +1,63 @@
+if PACKAGE_openvpn-wolfssl
+
+config OPENVPN_wolfssl
+	bool
+	default y
+	select WOLFSSL_HAS_OPENVPN
+
+config OPENVPN_wolfssl_ENABLE_LZO
+	bool "Enable LZO compression support"
+	default n
+
+config OPENVPN_wolfssl_ENABLE_LZ4
+	bool "Enable LZ4 compression support"
+	default y
+
+config OPENVPN_wolfssl_ENABLE_X509_ALT_USERNAME
+	bool "Enable the --x509-username-field feature"
+	default n
+
+#config OPENVPN_wolfssl_ENABLE_EUREPHIA
+#	bool "Enable support for the eurephia plug-in"
+#	default n
+
+config OPENVPN_wolfssl_ENABLE_MANAGEMENT
+	bool "Enable management server support"
+	default n
+
+#config OPENVPN_wolfssl_ENABLE_PKCS11
+#	bool "Enable pkcs11 support"
+#	default n
+
+config OPENVPN_wolfssl_ENABLE_FRAGMENT
+	bool "Enable internal fragmentation support (--fragment)"
+	default y
+
+config OPENVPN_wolfssl_ENABLE_MULTIHOME
+	bool "Enable multi-homed UDP server support (--multihome)"
+	default y
+
+config OPENVPN_wolfssl_ENABLE_PORT_SHARE
+	bool "Enable TCP server port-share support (--port-share)"
+	default y
+
+config OPENVPN_wolfssl_ENABLE_DEF_AUTH
+	bool "Enable deferred authentication"
+	default y
+
+config OPENVPN_wolfssl_ENABLE_PF
+	bool "Enable internal packet filter"
+	default y
+
+config OPENVPN_wolfssl_ENABLE_IPROUTE2
+	bool "Enable support for iproute2"
+	default n
+
+config OPENVPN_wolfssl_ENABLE_SMALL
+	bool "Enable size optimization"
+	default y
+	help
+	  enable smaller executable size (disable OCC, usage
+	  message, and verb 4 parm list)
+
+endif
diff --git a/net/openvpn/Makefile b/net/openvpn/Makefile
index d46b7bb73..9aeb43a84 100644
--- a/net/openvpn/Makefile
+++ b/net/openvpn/Makefile
@@ -10,7 +10,7 @@ include $(TOPDIR)/rules.mk
 PKG_NAME:=openvpn
 
 PKG_VERSION:=2.5.2
-PKG_RELEASE:=1
+PKG_RELEASE:=2
 
 PKG_SOURCE_URL:=\
 	https://build.openvpn.net/downloads/releases/ \
@@ -42,6 +42,7 @@ endef
 
 Package/openvpn-openssl=$(call Package/openvpn/Default,openssl,OpenSSL,+PACKAGE_openvpn-openssl:libopenssl)
 Package/openvpn-mbedtls=$(call Package/openvpn/Default,mbedtls,mbedTLS,+PACKAGE_openvpn-mbedtls:libmbedtls)
+Package/openvpn-wolfssl=$(call Package/openvpn/Default,wolfssl,WolfSSL \(experimental\),+PACKAGE_openvpn-wolfssl:libwolfssl)
 
 define Package/openvpn/config/Default
 	source "$(SOURCE)/Config-$(1).in"
@@ -49,6 +50,7 @@ endef
 
 Package/openvpn-openssl/config=$(call Package/openvpn/config/Default,openssl)
 Package/openvpn-mbedtls/config=$(call Package/openvpn/config/Default,mbedtls)
+Package/openvpn-wolfssl/config=$(call Package/openvpn/config/Default,wolfssl)
 
 ifeq ($(BUILD_VARIANT),mbedtls)
 CONFIG_OPENVPN_MBEDTLS:=y
@@ -56,6 +58,9 @@ endif
 ifeq ($(BUILD_VARIANT),openssl)
 CONFIG_OPENVPN_OPENSSL:=y
 endif
+ifeq ($(BUILD_VARIANT),wolfssl)
+CONFIG_OPENVPN_WOLFSSL:=y
+endif
 
 CONFIGURE_VARS += \
 	IPROUTE=/sbin/ip \
@@ -84,6 +89,7 @@ define Build/Configure
 		$(if $(CONFIG_OPENVPN_$(BUILD_VARIANT)_ENABLE_PORT_SHARE),--enable,--disable)-port-share \
 		$(if $(CONFIG_OPENVPN_OPENSSL),--with-crypto-library=openssl) \
 		$(if $(CONFIG_OPENVPN_MBEDTLS),--with-crypto-library=mbedtls) \
+		$(if $(CONFIG_OPENVPN_WOLFSSL),--with-crypto-library=wolfssl) \
 	)
 endef
 
@@ -142,3 +148,4 @@ endef
 
 $(eval $(call BuildPackage,openvpn-openssl))
 $(eval $(call BuildPackage,openvpn-mbedtls))
+$(eval $(call BuildPackage,openvpn-wolfssl))
diff --git a/net/openvpn/patches/002-add-wolfssl-support.patch b/net/openvpn/patches/002-add-wolfssl-support.patch
new file mode 100644
index 000000000..98bc65815
--- /dev/null
+++ b/net/openvpn/patches/002-add-wolfssl-support.patch
@@ -0,0 +1,190 @@
+From: Gert Doering <gert@greenie.muc.de>
+
+Support for wolfSSL in OpenVPN
+
+This patch adds support for wolfSSL in OpenVPN. Support is added by using
+wolfSSL's OpenSSL compatibility layer. Function calls are left unchanged
+and instead the OpenSSL includes point to wolfSSL headers and OpenVPN is
+linked against the wolfSSL library. The wolfSSL installation directory is
+detected using pkg-config.
+
+As requested by OpenVPN maintainers, this patch does not include
+wolfssl/options.h on its own. By defining the macro EXTERNAL_OPTS_OPENVPN
+in the configure script wolfSSL will include wolfssl/options.h on its own
+(change added in wolfSSL/wolfssl#2825). The patch
+adds an option '--disable-wolfssl-options-h' in case the user would like
+to supply their own settings file for wolfSSL.
+
+wolfSSL:
+Support added in: wolfSSL/wolfssl#2503
+
+git clone https://github.com/wolfSSL/wolfssl.git
+cd wolfssl
+./autogen.sh
+./configure --enable-openvpn
+make
+sudo make install
+
+OpenVPN:
+
+autoreconf -i -v -f
+./configure --with-crypto-library=wolfssl
+make
+make check
+sudo make install
+
+Signed-off-by: Juliusz Sosinowicz <juliusz@wolfssl.com>
+Acked-by: Arne Schwabe <arne@rfc2549.org>
+Message-Id: <20210317181153.83716-1-juliusz@wolfssl.com>
+URL: https://www.mail-archive.com/openvpn-devel@lists.sourceforge.net/msg21686.html
+Signed-off-by: Gert Doering <gert@greenie.muc.de>
+---
+ configure.ac | 110 ++++++++++++++++++++++++++++++++++++++++++++++++++++++-
+ src/openvpn/syshead.h | 3 ++-
+ 2 files changed, 110 insertions(+), 3 deletions(-)
+--- a/configure.ac
++++ b/configure.ac
+@@ -271,16 +271,23 @@ AC_ARG_WITH(
+ 
+ AC_ARG_WITH(
+ 	[crypto-library],
+-	[AS_HELP_STRING([--with-crypto-library=library], [build with the given crypto library, TYPE=openssl|mbedtls @<:@default=openssl@:>@])],
++	[AS_HELP_STRING([--with-crypto-library=library], [build with the given crypto library, TYPE=openssl|mbedtls|wolfssl @<:@default=openssl@:>@])],
+ 	[
+ 		case "${withval}" in
+-			openssl|mbedtls) ;;
++			openssl|mbedtls|wolfssl) ;;
+ 			*) AC_MSG_ERROR([bad value ${withval} for --with-crypto-library]) ;;
+ 		esac
+ 	],
+ 	[with_crypto_library="openssl"]
+ )
+ 
++AC_ARG_ENABLE(
++	[wolfssl-options-h],
++	[AS_HELP_STRING([--disable-wolfssl-options-h], [Disable including options.h in wolfSSL @<:@default=yes@:>@])],
++	,
++	[enable_wolfssl_options_h="yes"]
++)
++
+ AC_ARG_VAR([PLUGINDIR], [Path of plug-in directory @<:@default=LIBDIR/openvpn/plugins@:>@])
+ if test -n "${PLUGINDIR}"; then
+ 	plugindir="${PLUGINDIR}"
+@@ -1026,6 +1033,105 @@ elif test "${with_crypto_library}" = "mb
+ 	AC_DEFINE([ENABLE_CRYPTO_MBEDTLS], [1], [Use mbed TLS library])
+ 	CRYPTO_CFLAGS="${MBEDTLS_CFLAGS}"
+ 	CRYPTO_LIBS="${MBEDTLS_LIBS}"
++
++elif test "${with_crypto_library}" = "wolfssl"; then
++	AC_ARG_VAR([WOLFSSL_CFLAGS], [C compiler flags for wolfssl. The include directory should
++								  contain the regular wolfSSL header files but also the
++								  wolfSSL OpenSSL header files. Ex: -I/usr/local/include
++								  -I/usr/local/include/wolfssl])
++	AC_ARG_VAR([WOLFSSL_LIBS], [linker flags for wolfssl])
++
++	saved_CFLAGS="${CFLAGS}"
++	saved_LIBS="${LIBS}"
++
++	if test -z "${WOLFSSL_CFLAGS}" -a -z "${WOLFSSL_LIBS}"; then
++		# if the user did not explicitly specify flags, try to autodetect
++		PKG_CHECK_MODULES(
++			[WOLFSSL],
++			[wolfssl],
++			[],
++			[AC_MSG_ERROR([Could not find wolfSSL.])]
++		)
++		PKG_CHECK_VAR(
++			[WOLFSSL_INCLUDEDIR],
++			[wolfssl],
++			[includedir],
++			[],
++			[AC_MSG_ERROR([Could not find wolfSSL includedir variable.])]
++		)
++		WOLFSSL_CFLAGS="${WOLFSSL_CFLAGS} -I${WOLFSSL_INCLUDEDIR}/wolfssl"
++	fi
++	saved_CFLAGS="${CFLAGS}"
++	saved_LIBS="${LIBS}"
++	CFLAGS="${CFLAGS} ${WOLFSSL_CFLAGS}"
++	LIBS="${LIBS} ${WOLFSSL_LIBS}"
++
++	AC_CHECK_LIB(
++		[wolfssl],
++		[wolfSSL_Init],
++		[],
++		[AC_MSG_ERROR([Could not link wolfSSL library.])]
++	)
++	AC_CHECK_HEADER([wolfssl/options.h],,[AC_MSG_ERROR([wolfSSL header wolfssl/options.h not found!])])
++
++	# wolfSSL signal EKM support
++	have_export_keying_material="yes"
++
++	AC_DEFINE([HAVE_HMAC_CTX_NEW], [1], [Emulate AC_CHECK_FUNCS since these are defined as macros])
++	AC_DEFINE([HAVE_HMAC_CTX_FREE], [1], [Emulate AC_CHECK_FUNCS since these are defined as macros])
++	AC_DEFINE([HAVE_HMAC_CTX_RESET], [1], [Emulate AC_CHECK_FUNCS since these are defined as macros])
++	AC_DEFINE([HAVE_EVP_MD_CTX_NEW], [1], [Emulate AC_CHECK_FUNCS since these are defined as macros])
++	AC_DEFINE([HAVE_EVP_MD_CTX_FREE], [1], [Emulate AC_CHECK_FUNCS since these are defined as macros])
++	AC_DEFINE([HAVE_EVP_MD_CTX_RESET], [1], [Emulate AC_CHECK_FUNCS since these are defined as macros])
++	AC_DEFINE([HAVE_EVP_CIPHER_CTX_RESET], [1], [Emulate AC_CHECK_FUNCS since these are defined as macros])
++	AC_DEFINE([HAVE_OPENSSL_VERSION], [1], [Emulate AC_CHECK_FUNCS since these are defined as macros])
++	AC_DEFINE([HAVE_SSL_CTX_GET_DEFAULT_PASSWD_CB], [1], [Emulate AC_CHECK_FUNCS since these are defined as macros])
++	AC_DEFINE([HAVE_SSL_CTX_GET_DEFAULT_PASSWD_CB_USERDATA], [1], [Emulate AC_CHECK_FUNCS since these are defined as macros])
++	AC_DEFINE([HAVE_SSL_CTX_SET_SECURITY_LEVEL], [1], [Emulate AC_CHECK_FUNCS since these are defined as macros])
++	AC_DEFINE([HAVE_X509_GET0_NOTBEFORE], [1], [Emulate AC_CHECK_FUNCS since these are defined as macros])
++	AC_DEFINE([HAVE_X509_GET0_NOTAFTER], [1], [Emulate AC_CHECK_FUNCS since these are defined as macros])
++	AC_DEFINE([HAVE_X509_GET0_PUBKEY], [1], [Emulate AC_CHECK_FUNCS since these are defined as macros])
++	AC_DEFINE([HAVE_X509_STORE_GET0_OBJECTS], [1], [Emulate AC_CHECK_FUNCS since these are defined as macros])
++	AC_DEFINE([HAVE_X509_OBJECT_FREE], [1], [Emulate AC_CHECK_FUNCS since these are defined as macros])
++	AC_DEFINE([HAVE_X509_OBJECT_GET_TYPE], [1], [Emulate AC_CHECK_FUNCS since these are defined as macros])
++	AC_DEFINE([HAVE_EVP_PKEY_ID], [1], [Emulate AC_CHECK_FUNCS since these are defined as macros])
++	AC_DEFINE([HAVE_EVP_PKEY_GET0_RSA], [1], [Emulate AC_CHECK_FUNCS since these are defined as macros])
++	AC_DEFINE([HAVE_EVP_PKEY_GET0_DSA], [1], [Emulate AC_CHECK_FUNCS since these are defined as macros])
++	AC_DEFINE([HAVE_EVP_PKEY_GET0_EC_KEY], [1], [Emulate AC_CHECK_FUNCS since these are defined as macros])
++	AC_DEFINE([HAVE_RSA_SET_FLAGS], [1], [Emulate AC_CHECK_FUNCS since these are defined as macros])
++	AC_DEFINE([HAVE_RSA_BITS], [1], [Emulate AC_CHECK_FUNCS since these are defined as macros])
++	AC_DEFINE([HAVE_RSA_GET0_KEY], [1], [Emulate AC_CHECK_FUNCS since these are defined as macros])
++	AC_DEFINE([HAVE_RSA_SET0_KEY], [1], [Emulate AC_CHECK_FUNCS since these are defined as macros])
++	AC_DEFINE([HAVE_DSA_GET0_PQG], [1], [Emulate AC_CHECK_FUNCS since these are defined as macros])
++	AC_DEFINE([HAVE_DSA_BITS], [1], [Emulate AC_CHECK_FUNCS since these are defined as macros])
++	AC_DEFINE([HAVE_RSA_METH_NEW], [1], [Emulate AC_CHECK_FUNCS since these are defined as macros])
++	AC_DEFINE([HAVE_RSA_METH_FREE], [1], [Emulate AC_CHECK_FUNCS since these are defined as macros])
++	AC_DEFINE([HAVE_RSA_METH_SET_PUB_ENC], [1], [Emulate AC_CHECK_FUNCS since these are defined as macros])
++	AC_DEFINE([HAVE_RSA_METH_SET_PUB_DEC], [1], [Emulate AC_CHECK_FUNCS since these are defined as macros])
++	AC_DEFINE([HAVE_RSA_METH_SET_PRIV_ENC], [1], [Emulate AC_CHECK_FUNCS since these are defined as macros])
++	AC_DEFINE([HAVE_RSA_METH_SET_PRIV_DEC], [1], [Emulate AC_CHECK_FUNCS since these are defined as macros])
++	AC_DEFINE([HAVE_RSA_METH_SET_INIT], [1], [Emulate AC_CHECK_FUNCS since these are defined as macros])
++	AC_DEFINE([HAVE_RSA_METH_SET_SIGN], [1], [Emulate AC_CHECK_FUNCS since these are defined as macros])
++	AC_DEFINE([HAVE_RSA_METH_SET_FINISH], [1], [Emulate AC_CHECK_FUNCS since these are defined as macros])
++	AC_DEFINE([HAVE_RSA_METH_SET0_APP_DATA], [1], [Emulate AC_CHECK_FUNCS since these are defined as macros])
++	AC_DEFINE([HAVE_RSA_METH_GET0_APP_DATA], [1], [Emulate AC_CHECK_FUNCS since these are defined as macros])
++	AC_DEFINE([HAVE_EC_GROUP_ORDER_BITS], [1], [Emulate AC_CHECK_FUNCS since these are defined as macros])
++
++	if test "${enable_wolfssl_options_h}" = "yes"; then
++		AC_DEFINE([EXTERNAL_OPTS_OPENVPN], [1], [Include options.h from wolfSSL library])
++	else
++		AC_DEFINE([WOLFSSL_USER_SETTINGS], [1], [Use custom user_settings.h file for wolfSSL library])
++	fi
++
++	have_export_keying_material="yes"
++
++	CFLAGS="${saved_CFLAGS}"
++	LIBS="${saved_LIBS}"
++
++	AC_DEFINE([ENABLE_CRYPTO_WOLFSSL], [1], [Use wolfSSL crypto library])
++	AC_DEFINE([ENABLE_CRYPTO_OPENSSL], [1], [Use wolfSSL openssl compatibility layer])
++	CRYPTO_CFLAGS="${WOLFSSL_CFLAGS}"
++	CRYPTO_LIBS="${WOLFSSL_LIBS}"
+ else
+ 	AC_MSG_ERROR([Invalid crypto library: ${with_crypto_library}])
+ fi
+--- a/src/openvpn/syshead.h
++++ b/src/openvpn/syshead.h
+@@ -582,7 +582,8 @@ socket_defined(const socket_descriptor_t
+ /*
+  * Do we have CryptoAPI capability?
+  */
+-#if defined(_WIN32) && defined(ENABLE_CRYPTO_OPENSSL)
++#if defined(_WIN32) && defined(ENABLE_CRYPTO_OPENSSL) && \
++	!defined(ENABLE_CRYPTO_WOLFSSL)
+ #define ENABLE_CRYPTOAPI
+ #endif
+ 
diff --git a/net/openvpn/patches/210-build_always_use_internal_lz4.patch b/net/openvpn/patches/210-build_always_use_internal_lz4.patch
index a99f92364..267f62049 100644
--- a/net/openvpn/patches/210-build_always_use_internal_lz4.patch
+++ b/net/openvpn/patches/210-build_always_use_internal_lz4.patch
@@ -1,6 +1,6 @@
 --- a/configure.ac
 +++ b/configure.ac
-@@ -1077,68 +1077,15 @@ dnl
+@@ -1183,68 +1183,15 @@ dnl
  AC_ARG_VAR([LZ4_CFLAGS], [C compiler flags for lz4])
  AC_ARG_VAR([LZ4_LIBS], [linker flags for lz4])
  if test "$enable_lz4" = "yes" && test "$enable_comp_stub" = "no"; then
diff --git a/net/openvpn/test.sh b/net/openvpn/test.sh
index b51ccd6a1..c2b0cc4b0 100755
--- a/net/openvpn/test.sh
+++ b/net/openvpn/test.sh
@@ -7,4 +7,7 @@ case "$1" in
 	"openvpn-openssl")
 		openvpn --version | grep "$2.*SSL (OpenSSL)"
 		;;
+	"openvpn-wolfssl")
+		openvpn --version | grep "$2.*SSL (OpenSSL)"
+		;;
 esac