diff --git a/src/protocol-detail/new-renew-revoke.cpp b/src/protocol-detail/new-renew-revoke.cpp
index 9d6f5f8..b368c8c 100644
--- a/src/protocol-detail/new-renew-revoke.cpp
+++ b/src/protocol-detail/new-renew-revoke.cpp
@@ -97,6 +97,7 @@
   content.parse();
   const auto& ecdhKey = readString(content.get(tlv_ecdh_pub));
   const auto& salt = readString(content.get(tlv_salt));
+  uint64_t saltInt = std::stoull(salt);
   const auto& requestStatus = static_cast<Status>(readNonNegativeInteger(content.get(tlv_status)));
   const auto& requestId = readString(content.get(tlv_request_id));
   std::list<std::string> challenges;
@@ -105,7 +106,7 @@
       challenges.push_back(readString(element));
     }
   }
-  return DecodedData{ecdhKey, salt, requestId, requestStatus, challenges};
+  return DecodedData{ecdhKey, saltInt, requestId, requestStatus, challenges};
 }
 
 }  // namespace ndncert
diff --git a/src/protocol-detail/new-renew-revoke.hpp b/src/protocol-detail/new-renew-revoke.hpp
index 86c46d0..de5d558 100644
--- a/src/protocol-detail/new-renew-revoke.hpp
+++ b/src/protocol-detail/new-renew-revoke.hpp
@@ -40,7 +40,7 @@
                              const std::list<std::string>& challenges);
   struct DecodedData {
     std::string ecdhKey;
-    std::string salt;
+    uint64_t salt;
     std::string requestId;
     Status requestStatus;
     std::list<std::string> challenges;
diff --git a/src/requester.cpp b/src/requester.cpp
index 403736b..7530821 100644
--- a/src/requester.cpp
+++ b/src/requester.cpp
@@ -179,25 +179,20 @@
   if (!security::verifySignature(reply, *state.m_caItem.m_cert)) {
     _LOG_ERROR("Cannot verify replied Data packet signature.");
     BOOST_THROW_EXCEPTION(std::runtime_error("Cannot verify replied Data packet signature."));
-    return std::list<std::string>();
   }
   processIfError(reply);
 
   auto contentTLV = reply.getContent();
-  const auto content = NEW_RENEW_REVOKE::decodeDataContent(contentTLV);
+  const auto& content = NEW_RENEW_REVOKE::decodeDataContent(contentTLV);
 
-  // ECDH
-  uint64_t saltInt = std::stoull(content.salt);
+  // ECDH and HKDF
   state.m_ecdh.deriveSecret(content.ecdhKey);
-
-  // HKDF
   hkdf(state.m_ecdh.context->sharedSecret, state.m_ecdh.context->sharedSecretLen,
-       (uint8_t*)&saltInt, sizeof(saltInt), state.m_aesKey, sizeof(state.m_aesKey));
+       (uint8_t*)&content.salt, sizeof(content.salt), state.m_aesKey, sizeof(state.m_aesKey));
 
   // update state
   state.m_status = content.requestStatus;
   state.m_requestId = content.requestId;
-
   return content.challenges;
 }
 
@@ -246,7 +241,6 @@
   if (!security::verifySignature(reply, *state.m_caItem.m_cert)) {
     _LOG_ERROR("Cannot verify replied Data packet signature.");
     BOOST_THROW_EXCEPTION(std::runtime_error("Cannot verify replied Data packet signature."));
-    return;
   }
   processIfError(reply);
   auto result = decodeBlockWithAesGcm128(reply.getContent(), state.m_aesKey, (const uint8_t*)"test", strlen("test"));