diff --git a/activation.cpp b/activation.cpp
index 2979752..421902a 100644
--- a/activation.cpp
+++ b/activation.cpp
@@ -1,6 +1,5 @@
 #include "activation.hpp"
 #include "item_updater.hpp"
-#include "config.h"
 #include "serialize.hpp"
 #include <phosphor-logging/log.hpp>
 #include <sdbusplus/exception.hpp>
@@ -98,25 +97,16 @@
             }
 
 #ifdef WANT_SIGNATURE_VERIFY
-            using Signature = phosphor::software::image::Signature;
-
             fs::path uploadDir(IMG_UPLOAD_DIR);
-
-            Signature signature(uploadDir / versionId, SIGNED_IMAGE_CONF_PATH);
-
-            // Validate the signed image.
-            if (!signature.verify())
+            if (!verifySignature(uploadDir / versionId, SIGNED_IMAGE_CONF_PATH))
             {
-                log<level::ERR>("Error occurred during image validation");
-                report<InternalFailure>();
-
+                onVerifyFailed();
                 // Stop the activation process, if fieldMode is enabled.
                 if (parent.control::FieldMode::fieldModeEnabled())
                 {
                     // Cleanup
                     activationBlocksTransition.reset(nullptr);
                     activationProgress.reset(nullptr);
-
                     return softwareServer::Activation::activation(
                         softwareServer::Activation::Activations::Failed);
                 }
@@ -163,6 +153,19 @@
         }
 #else // !UBIFS_LAYOUT
 
+#ifdef WANT_SIGNATURE_VERIFY
+        fs::path uploadDir(IMG_UPLOAD_DIR);
+        if (!verifySignature(uploadDir / versionId, SIGNED_IMAGE_CONF_PATH))
+        {
+            onVerifyFailed();
+            // Stop the activation process, if fieldMode is enabled.
+            if (parent.control::FieldMode::fieldModeEnabled())
+            {
+                return softwareServer::Activation::activation(
+                    softwareServer::Activation::Activations::Failed);
+            }
+        }
+#endif
         parent.freeSpace();
 
         flashWrite();
@@ -260,6 +263,24 @@
     return;
 }
 
+#ifdef WANT_SIGNATURE_VERIFY
+bool Activation::verifySignature(const fs::path& imageDir,
+                                 const fs::path& confDir)
+{
+    using Signature = phosphor::software::image::Signature;
+
+    Signature signature(imageDir, confDir);
+
+    return signature.verify();
+}
+
+void Activation::onVerifyFailed()
+{
+    log<level::ERR>("Error occurred during image validation");
+    report<InternalFailure>();
+}
+#endif
+
 void ActivationBlocksTransition::enableRebootGuard()
 {
     log<level::INFO>("BMC image activating - BMC reboots are disabled.");
diff --git a/activation.hpp b/activation.hpp
index ba7c618..7f0120f 100644
--- a/activation.hpp
+++ b/activation.hpp
@@ -8,6 +8,12 @@
 #include "xyz/openbmc_project/Software/ActivationProgress/server.hpp"
 #include "org/openbmc/Associations/server.hpp"
 
+#include "config.h"
+
+#ifdef WANT_SIGNATURE_VERIFY
+#include <experimental/filesystem>
+#endif
+
 namespace phosphor
 {
 namespace software
@@ -15,6 +21,10 @@
 namespace updater
 {
 
+#ifdef WANT_SIGNATURE_VERIFY
+namespace fs = std::experimental::filesystem;
+#endif
+
 using AssociationList =
     std::vector<std::tuple<std::string, std::string, std::string>>;
 using ActivationInherit = sdbusplus::server::object::object<
@@ -320,6 +330,21 @@
     /** @brief Tracks if the service that updates the U-Boot environment
      *         variables has completed. **/
     bool ubootEnvVarsUpdated = false;
+
+#ifdef WANT_SIGNATURE_VERIFY
+  private:
+    /** @brief Verify signature of the images.
+     *
+     * @param[in] imageDir - The path of images to verify
+     * @param[in] confDir - The path of configs for verification
+     *
+     * @return true if verification successful and false otherwise
+     */
+    bool verifySignature(const fs::path& imageDir, const fs::path& confDir);
+
+    /** @brief Called when image verification fails. */
+    void onVerifyFailed();
+#endif
 };
 
 } // namespace updater