uencrypt: add package to decrypt WG4хх223 config

This adds a simple AES-128-CBC encryption/decryption program using
either wolfSSL or OpenSSL as backend to decrypt Arcadyan WG4xx223
configuration partitions.  The ipk size is 3,355 bytes.

Signed-off-by: Eneas U de Queiroz <cotequeiroz@gmail.com>

package/utils/uencrypt/Makefile

@@ -0,0 +1,57 @@
+# SPDX-License-Identifier: GPL-2.0-or-later
+# Copyright (C) 2022 Eneas Ulir de Queiroz
+
+include $(TOPDIR)/rules.mk
+
+PKG_NAME:=uencrypt
+PKG_RELEASE:=1
+
+PKG_FLAGS:=nonshared
+PKG_LICENSE:=GPL-2.0-or-later
+PKG_MAINTAINER:=Eneas U de Queiroz <cotequeiroz@gmail.com>
+PKG_CONFIG_DEPENDS:=\
+	CONFIG_UENCRYPT_OPENSSL \
+	CONFIG_UENCRYPT_WOLFSSL
+
+include $(INCLUDE_DIR)/package.mk
+include $(INCLUDE_DIR)/cmake.mk
+
+CMAKE_INSTALL:=1
+CMAKE_OPTIONS+=$(if $(CONFIG_UENCRYPT_WOLFSSL),-DUSE_WOLFSSL=1)
+
+define Package/uencrypt
+  SECTION:=utils
+  CATEGORY:=Base system
+  TITLE:=Decryption utility for Arcadyan WG4xx223
+  DEPENDS:=@TARGET_ramips_mt7621 +UENCRYPT_WOLFSSL:libwolfssl +UENCRYPT_OPENSSL:libopenssl
+endef
+
+define Package/uencrypt/description
+  This is a small AES-128-CBC encrypton/decryption program.
+  Even though it can be used for regular encryption and
+  decryption operations using AES-128-CBC, it is included
+  here to unencrypt the configuration from mtd on Arcadyan
+  WG430223 and WG443223 routers.
+endef
+
+define Package/uencrypt/config
+  if PACKAGE_uencrypt
+    choice
+	prompt "Crypto provider"
+	default UENCRYPT_WOLFSSL
+
+	config UENCRYPT_OPENSSL
+	bool "OpenSSL"
+
+	config UENCRYPT_WOLFSSL
+	bool "wolfSSL"
+    endchoice
+  endif
+endef
+
+define Package/uencrypt/install
+	$(INSTALL_DIR) $(1)/usr/bin
+	$(INSTALL_BIN) $(PKG_INSTALL_DIR)/usr/bin/uencrypt $(1)/usr/bin
+endef
+
+$(eval $(call BuildPackage,uencrypt))