crypto: add Eclipse tinydtls support

LICENSE

@@ -1807,3 +1807,18 @@ apps/testing/crypto/hmac.c
  WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+
+apps/crypto/tinydtls
+======================
+ /*******************************************************************************
+  * Copyright (c) 2011, 2012, 2013, 2014, 2015, 2016 Olaf Bergmann (TZI) and others.
+  * All rights reserved. This program and the accompanying materials
+  * are made available under the terms of the Eclipse Public License v1.0
+  * and Eclipse Distribution License v. 1.0 which accompanies this distribution.
+  * The Eclipse Public License is available at http://www.eclipse.org/legal/epl-v10.html
+  * and the Eclipse Distribution License is available at
+  * http://www.eclipse.org/org/documents/edl-v10.php.
+  * Contributors:
+  *    Olaf Bergmann  - initial API and implementation
+  *    Hauke Mehrtens - memory optimization, ECC integration
+  *******************************************************************************/

crypto/tinydtls/.gitignore

@@ -0,0 +1,2 @@
+/tinydtls
+/*.tar.gz

crypto/tinydtls/CMakeLists.txt

@@ -0,0 +1,92 @@
+# ##############################################################################
+# apps/crypto/tinydtls/CMakeLists.txt
+#
+# Licensed to the Apache Software Foundation (ASF) under one or more contributor
+# license agreements.  See the NOTICE file distributed with this work for
+# additional information regarding copyright ownership.  The ASF licenses this
+# file to you under the Apache License, Version 2.0 (the "License"); you may not
+# use this file except in compliance with the License.  You may obtain a copy of
+# the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+# License for the specific language governing permissions and limitations under
+# the License.
+#
+# ##############################################################################
+
+if(CONFIG_CRYPTO_TINYDTLS)
+
+  if(NOT EXISTS ${CMAKE_CURRENT_LIST_DIR}/tinydtls)
+    FetchContent_Declare(
+      tinydtls
+      DOWNLOAD_NAME "${CONFIG_TINYDTLS_VERSION}.tar.gz"
+      DOWNLOAD_DIR ${CMAKE_CURRENT_LIST_DIR}
+      URL "https://github.com/eclipse/tinydtls/archive/${CONFIG_TINYDTLS_VERSION}.tar.gz"
+          SOURCE_DIR
+          ${CMAKE_CURRENT_LIST_DIR}/tinydtls
+          BINARY_DIR
+          ${CMAKE_BINARY_DIR}/apps/crypto/tinydtls/tinydtls
+          CONFIGURE_COMMAND
+          ""
+          BUILD_COMMAND
+          ""
+          INSTALL_COMMAND
+          ""
+          TEST_COMMAND
+          ""
+      DOWNLOAD_NO_PROGRESS true
+      TIMEOUT 30)
+
+    FetchContent_GetProperties(tinydtls)
+
+    if(NOT tinydtls_POPULATED)
+      FetchContent_Populate(tinydtls)
+    endif()
+  endif()
+
+  add_subdirectory(tinydtls)
+
+  target_compile_definitions(
+    tinydtls
+    PRIVATE HAVE_ARPA_INET_H
+            HAVE_ASSERT_H
+            HAVE_FCNTL_H
+            HAVE_GETRANDOM
+            HAVE_INTTYPES_H
+            HAVE_MEMSET
+            HAVE_NETDB_H
+            HAVE_NETINET_IN_H
+            HAVE_RANDOM
+            HAVE_SELECT
+            HAVE_SOCKET
+            HAVE_STDDEF_H
+            HAVE_STDINT_H
+            HAVE_STDLIB_H
+            HAVE_STRDUP
+            HAVE_STRERROR
+            HAVE_STRINGS_H
+            HAVE_STRING_H
+            HAVE_STRNLEN
+            HAVE_SYS_SOCKET_H
+            HAVE_SYS_STAT_H
+            HAVE_SYS_TIME_H
+            HAVE_SYS_TYPES_H
+            HAVE_TIME_H
+            HAVE_UNISTD_H
+            HAVE_VPRINTF
+            HAVE_SNPRINTF)
+
+  target_compile_options(tinydtls PRIVATE -Wno-unused -Wno-inline)
+
+  # TODO: this should be function in nuttx/cmake/nuttx_add_library.cmake
+  set_property(GLOBAL APPEND PROPERTY NUTTX_EXTRA_LIBRARIES tinydtls)
+  nuttx_add_library_internal(tinydtls)
+
+  # allow #include "tinydtls/xxx.h"
+  target_include_directories(tinydtls PUBLIC .)
+
+endif()

crypto/tinydtls/Kconfig

@@ -0,0 +1,19 @@
+#
+# For a description of the syntax of this configuration file,
+# see the file kconfig-language.txt in the NuttX tools repository.
+#
+
+config CRYPTO_TINYDTLS
+	bool "Eclipse Tinydtls"
+	default n
+	depends on ALLOW_ECLIPSE_COMPONENTS
+	---help---
+		Enable Eclipse tinydtls - a minimal library for DTLS.
+
+if CRYPTO_TINYDTLS
+
+config TINYDTLS_VERSION
+	string "Tinydtls version"
+	default "ba830a390642d057fcf21bbb6bd57546d12e584c"
+
+endif # CRYPTO_TINYDTLS