Use Mbedtls files directly (#226)

* Switch to pico-sdk style mbedtls library

* Initialize PICO_MBEDTLS_PATH in same way as SDK

Author: will-v-pi

CMakeLists.txt

@@ -203,11 +203,6 @@ add_subdirectory(picoboot_connection)
 add_subdirectory(elf)
 add_subdirectory(elf2uf2)
 
-# To configure mbedtls
-# todo make the configuration better
-set(MBEDTLS_CONFIG_FILE "mbedtls_config.h")
-add_compile_options(-I${CMAKE_SOURCE_DIR}/lib/include)
-
 add_subdirectory(lib)
 
 add_subdirectory(bintool)

lib/BUILD.bazel

@@ -1,6 +1,6 @@
 cc_library(
     name = "mbedtls_config",
-    hdrs = ["include/mbedtls_config.h"],
+    hdrs = ["include/mbedtls_config.h", "include/picotool_mbedtls_config.h"],
     includes = ["include"],
     visibility = ["@mbedtls//:__subpackages__"],
 )

lib/CMakeLists.txt

@@ -20,8 +20,132 @@ add_subdirectory(nlohmann_json EXCLUDE_FROM_ALL)
 
 add_subdirectory(whereami EXCLUDE_FROM_ALL)
 
-if(EXISTS "${PICO_SDK_PATH}/lib/mbedtls/CMakeLists.txt")
-    option(ENABLE_PROGRAMS "Build Mbed TLS programs." OFF)
-    option(ENABLE_TESTING "Build Mbed TLS tests." OFF)
-    add_subdirectory(${PICO_SDK_PATH}/lib/mbedtls mbedtls EXCLUDE_FROM_ALL)
+# Taken from pico-sdk/src/rp2_common/pico_mbedtls/CMakeLists.txt
+if (DEFINED ENV{PICO_MBEDTLS_PATH} AND (NOT PICO_MBEDTLS_PATH))
+    set(PICO_MBEDTLS_PATH $ENV{PICO_MBEDTLS_PATH})
+    message("Using PICO_MBEDTLS_PATH from environment ('${PICO_MBEDTLS_PATH}')")
+endif()
+
+set(MBEDTLS_TEST_PATH "library/aes.c")
+if (NOT PICO_MBEDTLS_PATH)
+    set(PICO_MBEDTLS_PATH ${PICO_SDK_PATH}/lib/mbedtls)
+elseif (NOT EXISTS "${PICO_MBEDTLS_PATH}/${MBEDTLS_TEST_PATH}")
+    message(WARNING "PICO_MBEDTLS_PATH specified but content not present.")
+endif()
+
+if(EXISTS "${PICO_MBEDTLS_PATH}/${MBEDTLS_TEST_PATH}")
+    # Support version 2.28.8 or 3.6.2
+    if (EXISTS ${PICO_MBEDTLS_PATH}/library/ssl_cli.c)
+        set(MBEDTLS_VERSION_MAJOR 2)
+    elseif (EXISTS ${PICO_MBEDTLS_PATH}/library/ssl_client.c)
+        set(MBEDTLS_VERSION_MAJOR 3)
+    else()
+        message(WARNING "Cannot determine the version of mbedtls")
+    endif()
+
+    function(src_crypto_list)
+        set(src_crypto
+            aes.c
+            aesni.c
+            aria.c
+            asn1parse.c
+            asn1write.c
+            base64.c
+            bignum.c
+            camellia.c
+            ccm.c
+            chacha20.c
+            chachapoly.c
+            cipher.c
+            cipher_wrap.c
+            constant_time.c
+            cmac.c
+            ctr_drbg.c
+            des.c
+            dhm.c
+            ecdh.c
+            ecdsa.c
+            ecjpake.c
+            ecp.c
+            ecp_curves.c
+            entropy.c
+            entropy_poll.c
+            error.c
+            gcm.c
+            hkdf.c
+            hmac_drbg.c
+            md.c
+            md5.c
+            memory_buffer_alloc.c
+            mps_reader.c
+            mps_trace.c
+            nist_kw.c
+            oid.c
+            padlock.c
+            pem.c
+            pk.c
+            pk_wrap.c
+            pkcs12.c
+            pkcs5.c
+            pkparse.c
+            pkwrite.c
+            platform.c
+            platform_util.c
+            poly1305.c
+            psa_crypto.c
+            psa_crypto_aead.c
+            psa_crypto_cipher.c
+            psa_crypto_client.c
+            psa_crypto_ecp.c
+            psa_crypto_hash.c
+            psa_crypto_mac.c
+            psa_crypto_rsa.c
+            psa_crypto_se.c
+            psa_crypto_slot_management.c
+            psa_crypto_storage.c
+            psa_its_file.c
+            ripemd160.c
+            rsa.c
+            sha1.c
+            sha256.c
+            sha512.c
+            threading.c
+            timing.c
+            version.c
+            version_features.c
+        )
+        if (MBEDTLS_VERSION_MAJOR EQUAL 2)
+            list(APPEND src_crypto
+                arc4.c
+                blowfish.c
+                havege.c
+                md2.c
+                md4.c
+                psa_crypto_driver_wrappers.c
+                rsa_internal.c xtea.c
+            )
+        elseif (MBEDTLS_VERSION_MAJOR EQUAL 3)
+            list(APPEND src_crypto
+                bignum_core.c
+                rsa_alt_helpers.c
+                pk_ecc.c
+            )
+        endif()
+        list(TRANSFORM src_crypto PREPEND ${PICO_MBEDTLS_PATH}/library/)
+        set(src_crypto ${src_crypto} PARENT_SCOPE)
+    endfunction()
+
+    src_crypto_list()
+
+
+    # Create library
+    add_library(mbedtls STATIC ${src_crypto})
+
+    if(WIN32)
+        target_link_libraries(mbedtls ws2_32 bcrypt)
+    endif(WIN32)
+
+    target_compile_definitions(mbedtls PUBLIC MBEDTLS_CONFIG_FILE="picotool_mbedtls_config.h")
+    target_include_directories(mbedtls SYSTEM PUBLIC ${PICO_MBEDTLS_PATH}/include)
+    target_include_directories(mbedtls PUBLIC ${CMAKE_CURRENT_LIST_DIR}/include)
 endif()