netsnmp: Add option for using minimal internal SSL code

Add option for enabling a minimal internal copy of OpenSSL usable for USM
security. It will not enable the usage of SNMP over (D)TLS.

[Thomas: use 'else ifeq' to avoid having another nested ifeq ... endif
block.]

Signed-off-by: Stefan Sørensen <stefan.sorensen@spectralink.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

package/netsnmp/Config.in

@@ -49,4 +49,11 @@ config BR2_PACKAGE_NETSNMP_ENABLE_DEBUGGING
 	  support, including the ability to log with DEBUGMSG(),
 	  DEBUGMSGTL() and companion macros.
 
+config BR2_PACKAGE_NETSNMP_OPENSSL_INTERNAL
+	bool "Enable minimal internal OpenSSL code"
+	depends on !BR2_PACKAGE_OPENSSL
+	help
+	  Enable a minimal internal copy of OpenSSL usable for USM
+	  security. It will not enable the usage of SNMP over (D)TLS.
+
 endif

package/netsnmp/netsnmp.mk

@@ -54,6 +54,8 @@ ifeq ($(BR2_STATIC_LIBS),y)
 	# openssl uses zlib, so we need to explicitly link with it when static
 	NETSNMP_CONF_ENV += LIBS=-lz
 endif
+else ifeq ($(BR2_PACKAGE_NETSNMP_OPENSSL_INTERNAL),y)
+	NETSNMP_CONF_OPTS += --with-openssl=internal
 else
 	NETSNMP_CONF_OPTS += --without-openssl
 endif