3rdparty: Add additional build facilities for 3rd-party code
diff --git a/3rdparty/everest/CMakeLists.txt b/3rdparty/everest/CMakeLists.txt
index 84e2763..5b0a078 100644
--- a/3rdparty/everest/CMakeLists.txt
+++ b/3rdparty/everest/CMakeLists.txt
@@ -1,10 +1,40 @@
-include_directories(include include/everest include/everest/kremlib)
+list (APPEND everest_src)
+list (APPEND everest_inc)
+list (APPEND everest_def)
 
-set(src_everest
-  ${CMAKE_CURRENT_SOURCE_DIR}/library/everest.c
-  ${CMAKE_CURRENT_SOURCE_DIR}/library/Hacl_Curve25519.c
-  ${CMAKE_CURRENT_SOURCE_DIR}/library/x25519.c
-  ${CMAKE_CURRENT_SOURCE_DIR}/library/kremlib/FStar_UInt64_FStar_UInt32_FStar_UInt16_FStar_UInt8.c
-  PARENT_SCOPE
-)
+execute_process(COMMAND ${PERL_EXECUTABLE} scripts/config.pl -f include/mbedtls/config.h get MBEDTLS_ECDH_VARIANT_EVEREST_ENABLED RESULT_VARIABLE result)
 
+if(${result} EQUAL 0)
+  set(everest_src
+    ${CMAKE_CURRENT_SOURCE_DIR}/library/everest.c
+    ${CMAKE_CURRENT_SOURCE_DIR}/library/x25519.c
+    ${CMAKE_CURRENT_SOURCE_DIR}/library/kremlib/FStar_UInt64_FStar_UInt32_FStar_UInt16_FStar_UInt8.c
+  )
+
+  if (${CMAKE_LIBRARY_ARCHITECTURE} STREQUAL "x86_64-linux-gnu")
+  list(APPEND everest_src ${CMAKE_CURRENT_SOURCE_DIR}/library/Hacl_Curve25519.c)
+  else()
+  list(APPEND everest_def -DKRML_VERIFIED_UINT128)
+  list(APPEND everest_src
+    ${CMAKE_CURRENT_SOURCE_DIR}/library/legacy/Hacl_Curve25519.c
+    ${CMAKE_CURRENT_SOURCE_DIR}/library/kremlib/FStar_UInt128_extracted.c
+  )
+  endif()
+
+  list(APPEND everest_inc ${CMAKE_CURRENT_SOURCE_DIR}/../../include ${CMAKE_CURRENT_SOURCE_DIR}/include ${CMAKE_CURRENT_SOURCE_DIR}/include/everest ${CMAKE_CURRENT_SOURCE_DIR}/include/everest/kremlib)
+
+  if(INSTALL_MBEDTLS_HEADERS)
+
+      file(GLOB_RECURSE headers "${CMAKE_CURRENT_SOURCE_DIR}/include/everest/*.h")
+
+      install(FILES ${headers}
+          DESTINATION include/everest
+          PERMISSIONS OWNER_READ OWNER_WRITE GROUP_READ WORLD_READ)
+
+  endif(INSTALL_MBEDTLS_HEADERS)
+
+endif()
+
+set(thirdparty_src ${thirdparty_src} ${everest_src} PARENT_SCOPE)
+set(thirdparty_inc ${thirdparty_inc} ${everest_inc} PARENT_SCOPE)
+set(thirdparty_def ${thirdparty_def} ${everest_def} PARENT_SCOPE)