diff --git a/ndn-cxx/security/verification-helpers.cpp b/ndn-cxx/security/verification-helpers.cpp
index 2f5927e..44519b4 100644
--- a/ndn-cxx/security/verification-helpers.cpp
+++ b/ndn-cxx/security/verification-helpers.cpp
@@ -80,13 +80,6 @@
 }
 
 bool
-verifySignature(const uint8_t* blob, size_t blobLen, const uint8_t* sig, size_t sigLen,
-                const transform::PublicKey& key)
-{
-  return verifySignature({{blob, blobLen}}, sig, sigLen, key);
-}
-
-bool
 verifySignature(const InputBuffers& blobs, const uint8_t* sig, size_t sigLen,
                 const uint8_t* key, size_t keyLen)
 {
@@ -101,13 +94,6 @@
   return verifySignature(blobs, sig, sigLen, pKey);
 }
 
-bool
-verifySignature(const uint8_t* blob, size_t blobLen, const uint8_t* sig, size_t sigLen,
-                const uint8_t* key, size_t keyLen)
-{
-  return verifySignature({{blob, blobLen}}, sig, sigLen, key, keyLen);
-}
-
 static ParseResult
 parse(const Data& data)
 {
@@ -144,8 +130,8 @@
       }
 
       const Block& nameBlock = interestName.wireEncode();
-      Block sigValue = interestName[signed_interest::POS_SIG_VALUE].blockFromValue();
       SignatureInfo info(interestName[signed_interest::POS_SIG_INFO].blockFromValue());
+      Block sigValue(interestName[signed_interest::POS_SIG_VALUE].blockFromValue());
       return ParseResult(info,
                          {{nameBlock.value(),
                            nameBlock.value_size() - interestName[signed_interest::POS_SIG_VALUE].size()}},
@@ -159,22 +145,60 @@
 }
 
 static bool
-verifySignature(ParseResult params, const transform::PublicKey& key)
+verifySignature(const ParseResult& params, const transform::PublicKey& key)
 {
   return !params.bufs.empty() && verifySignature(params.bufs, params.sig, params.sigLen, key);
 }
 
 static bool
-verifySignature(ParseResult params, const tpm::Tpm& tpm, const Name& keyName,
-                DigestAlgorithm digestAlgorithm)
+verifySignature(const ParseResult& params, const uint8_t* key, size_t keyLen)
 {
-  return !params.bufs.empty() && bool(tpm.verify(params.bufs, params.sig, params.sigLen, keyName, digestAlgorithm));
+  return !params.bufs.empty() && verifySignature(params.bufs, params.sig, params.sigLen, key, keyLen);
 }
 
 static bool
-verifySignature(ParseResult params, const uint8_t* key, size_t keyLen)
+verifySignature(const ParseResult& params, const tpm::Tpm& tpm, const Name& keyName,
+                DigestAlgorithm digestAlgorithm)
 {
-  return !params.bufs.empty() && verifySignature(params.bufs, params.sig, params.sigLen, key, keyLen);
+  return !params.bufs.empty() && bool(tpm.verify(params.bufs, params.sig, params.sigLen, keyName,
+                                                 digestAlgorithm));
+}
+
+static bool
+verifyDigest(const ParseResult& params, DigestAlgorithm algorithm)
+{
+  if (params.bufs.empty()) {
+    return false;
+  }
+
+  OBufferStream os;
+  try {
+    using namespace transform;
+    bufferSource(params.bufs) >> digestFilter(algorithm) >> streamSink(os);
+  }
+  catch (const transform::Error&) {
+    return false;
+  }
+  auto result = os.buf();
+
+  if (result->size() != params.sigLen) {
+    return false;
+  }
+
+  // constant-time buffer comparison to mitigate timing attacks
+  return CRYPTO_memcmp(result->data(), params.sig, params.sigLen) == 0;
+}
+
+bool
+verifySignature(const Data& data, const uint8_t* key, size_t keyLen)
+{
+  return verifySignature(parse(data), key, keyLen);
+}
+
+bool
+verifySignature(const Interest& interest, const uint8_t* key, size_t keyLen)
+{
+  return verifySignature(parse(interest), key, keyLen);
 }
 
 bool
@@ -202,32 +226,18 @@
 }
 
 bool
-verifySignature(const Data& data, const uint8_t* key, size_t keyLen)
-{
-  return verifySignature(parse(data), key, keyLen);
-}
-
-bool
-verifySignature(const Interest& interest, const uint8_t* key, size_t keyLen)
-{
-  return verifySignature(parse(interest), key, keyLen);
-}
-
-bool
 verifySignature(const Data& data, const optional<Certificate>& cert)
 {
   auto parsed = parse(data);
   if (cert) {
     return verifySignature(parsed, cert->getContent().value(), cert->getContent().value_size());
   }
+  else if (parsed.info.getSignatureType() == tlv::SignatureTypeValue::DigestSha256) {
+    return verifyDigest(parsed, DigestAlgorithm::SHA256);
+  }
+  // Add any other self-verifying signatures here (if any)
   else {
-    if (parsed.info.getSignatureType() == tlv::SignatureTypeValue::DigestSha256) {
-      return verifyDigest(data, DigestAlgorithm::SHA256);
-    }
-    // Add any other self-verifying signatures here (if any)
-    else {
-      return false;
-    }
+    return false;
   }
 }
 
@@ -238,14 +248,12 @@
   if (cert) {
     return verifySignature(parsed, cert->getContent().value(), cert->getContent().value_size());
   }
+  else if (parsed.info.getSignatureType() == tlv::SignatureTypeValue::DigestSha256) {
+    return verifyDigest(parsed, DigestAlgorithm::SHA256);
+  }
+  // Add any other self-verifying signatures here (if any)
   else {
-    if (parsed.info.getSignatureType() == tlv::SignatureTypeValue::DigestSha256) {
-      return verifyDigest(interest, DigestAlgorithm::SHA256);
-    }
-    // Add any other self-verifying signatures here (if any)
-    else {
-      return false;
-    }
+    return false;
   }
 }
 
@@ -263,53 +271,5 @@
   return verifySignature(parse(interest), tpm, keyName, digestAlgorithm);
 }
 
-///////////////////////////////////////////////////////////////////////
-
-bool
-verifyDigest(const InputBuffers& bufs, const uint8_t* digest, size_t digestLen,
-             DigestAlgorithm algorithm)
-{
-  using namespace transform;
-
-  OBufferStream os;
-  try {
-    bufferSource(bufs) >> digestFilter(algorithm) >> streamSink(os);
-  }
-  catch (const transform::Error&) {
-    return false;
-  }
-  ConstBufferPtr result = os.buf();
-
-  if (result->size() != digestLen) {
-    return false;
-  }
-
-  // constant-time buffer comparison to mitigate timing attacks
-  return CRYPTO_memcmp(result->data(), digest, digestLen) == 0;
-}
-
-bool
-verifyDigest(const uint8_t* blob, size_t blobLen, const uint8_t* digest, size_t digestLen,
-             DigestAlgorithm algorithm)
-{
-  return verifyDigest({{blob, blobLen}}, digest, digestLen, algorithm);
-}
-
-bool
-verifyDigest(const Data& data, DigestAlgorithm algorithm)
-{
-  ParseResult parseResult = parse(data);
-  return !parseResult.bufs.empty() && verifyDigest(parseResult.bufs, parseResult.sig,
-                                                   parseResult.sigLen, algorithm);
-}
-
-bool
-verifyDigest(const Interest& interest, DigestAlgorithm algorithm)
-{
-  ParseResult parseResult = parse(interest);
-  return !parseResult.bufs.empty() && verifyDigest(parseResult.bufs, parseResult.sig,
-                                                   parseResult.sigLen, algorithm);
-}
-
 } // namespace security
 } // namespace ndn
diff --git a/ndn-cxx/security/verification-helpers.hpp b/ndn-cxx/security/verification-helpers.hpp
index 09b7b57..65ca8c5 100644
--- a/ndn-cxx/security/verification-helpers.hpp
+++ b/ndn-cxx/security/verification-helpers.hpp
@@ -56,13 +56,6 @@
                 const transform::PublicKey& key);
 
 /**
- * @brief Verify @p blob using @p key against @p sig.
- */
-bool
-verifySignature(const uint8_t* blob, size_t blobLen, const uint8_t* sig, size_t sigLen,
-                const transform::PublicKey& key);
-
-/**
  * @brief Verify @p blobs using @p key against @p sig.
  * @note @p key must be a public key in PKCS #8 format.
  */
@@ -71,14 +64,6 @@
                 const uint8_t* key, size_t keyLen);
 
 /**
- * @brief Verify @p blob using @p key against @p sig.
- * @note @p key must be a public key in PKCS #8 format.
- */
-bool
-verifySignature(const uint8_t* blob, size_t blobLen, const uint8_t* sig, size_t sigLen,
-                const uint8_t* key, size_t keyLen);
-
-/**
  * @brief Verify @p data using @p key.
  * @note @p key must be a public key in PKCS #8 format.
  */
@@ -156,36 +141,6 @@
 verifySignature(const Interest& interest, const tpm::Tpm& tpm, const Name& keyName,
                 DigestAlgorithm digestAlgorithm);
 
-//////////////////////////////////////////////////////////////////
-
-/**
- * @brief Verify @p blobs against @p digest using @p algorithm.
- */
-bool
-verifyDigest(const InputBuffers& blobs, const uint8_t* digest, size_t digestLen,
-             DigestAlgorithm algorithm);
-
-/**
- * @brief Verify @p blob against @p digest using @p algorithm.
- */
-bool
-verifyDigest(const uint8_t* blob, size_t blobLen, const uint8_t* digest, size_t digestLen,
-             DigestAlgorithm algorithm);
-
-/**
- * @brief Verify @p data against digest @p algorithm.
- */
-bool
-verifyDigest(const Data& data, DigestAlgorithm algorithm);
-
-/**
- * @brief Verify @p interest against digest @p algorithm.
- * @note This method verifies only signature of the signed interest.
- * @sa docs/specs/signed-interest.rst
- */
-bool
-verifyDigest(const Interest& interest, DigestAlgorithm algorithm);
-
 } // namespace security
 } // namespace ndn
 
diff --git a/tests/unit/security/key-chain.t.cpp b/tests/unit/security/key-chain.t.cpp
index d3fb67e..1aa76b8 100644
--- a/tests/unit/security/key-chain.t.cpp
+++ b/tests/unit/security/key-chain.t.cpp
@@ -1,6 +1,6 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
 /*
- * Copyright (c) 2013-2020 Regents of the University of California.
+ * Copyright (c) 2013-2021 Regents of the University of California.
  *
  * This file is part of ndn-cxx library (NDN C++ library with eXperimental eXtensions).
  *
@@ -526,7 +526,7 @@
   bool
   verify(const SigningInfo&) const
   {
-    return verifyDigest(this->packet, DigestAlgorithm::SHA256);
+    return verifySignature(this->packet, nullopt);
   }
 };
 
@@ -544,7 +544,9 @@
   Sha256Signing<InterestV02Pkt>,
   Sha256Signing<InterestV03Pkt>,
   SigningWithNonDefaultIdentity<DataPkt>,
-  SigningWithNonDefaultKey<DataPkt>
+  SigningWithNonDefaultIdentity<InterestV03Pkt>,
+  SigningWithNonDefaultKey<DataPkt>,
+  SigningWithNonDefaultKey<InterestV03Pkt>
 >;
 
 BOOST_FIXTURE_TEST_CASE_TEMPLATE(SigningInterface, T, SigningTests, T)
diff --git a/tests/unit/security/transform/signer-filter.t.cpp b/tests/unit/security/transform/signer-filter.t.cpp
index 4f3fa04..4f84582 100644
--- a/tests/unit/security/transform/signer-filter.t.cpp
+++ b/tests/unit/security/transform/signer-filter.t.cpp
@@ -1,6 +1,6 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
 /*
- * Copyright (c) 2013-2019 Regents of the University of California.
+ * Copyright (c) 2013-2021 Regents of the University of California.
  *
  * This file is part of ndn-cxx library (NDN C++ library with eXperimental eXtensions).
  *
@@ -92,7 +92,7 @@
   bufferSource(DATA, sizeof(DATA)) >> signerFilter(DigestAlgorithm::SHA256, sKey) >> streamSink(os2);
   auto sig = os2.buf();
 
-  BOOST_CHECK(verifySignature(DATA, sizeof(DATA), sig->data(), sig->size(), pubKey->data(), pubKey->size()));
+  BOOST_TEST(verifySignature({{DATA, sizeof(DATA)}}, sig->data(), sig->size(), pubKey->data(), pubKey->size()));
 }
 
 BOOST_AUTO_TEST_CASE(Ecdsa)
@@ -128,7 +128,7 @@
   bufferSource(DATA, sizeof(DATA)) >> signerFilter(DigestAlgorithm::SHA256, sKey) >> streamSink(os2);
   auto sig = os2.buf();
 
-  BOOST_CHECK(verifySignature(DATA, sizeof(DATA), sig->data(), sig->size(), pubKey->data(), pubKey->size()));
+  BOOST_TEST(verifySignature({{DATA, sizeof(DATA)}}, sig->data(), sig->size(), pubKey->data(), pubKey->size()));
 }
 
 BOOST_AUTO_TEST_SUITE(Hmac)
diff --git a/tests/unit/security/verification-helpers.t.cpp b/tests/unit/security/verification-helpers.t.cpp
index 74ffbe0..f35f93f 100644
--- a/tests/unit/security/verification-helpers.t.cpp
+++ b/tests/unit/security/verification-helpers.t.cpp
@@ -41,7 +41,7 @@
 // BOOST_FIXTURE_TEST_CASE(Generator, KeyChainFixture)
 // {
 //   Identity wrongIdentity = m_keyChain.createIdentity("/Security/TestVerificationHelpers/Wrong");
-//   std::map<std::string, SigningInfo> identities = {
+//   const std::map<std::string, SigningInfo> identities = {
 //     {"Ecdsa", signingByIdentity(m_keyChain.createIdentity("/Security/TestVerificationHelpers/EC", EcKeyParams()))},
 //     {"Rsa", signingByIdentity(m_keyChain.createIdentity("/Security/TestVerificationHelpers/RSA", RsaKeyParams()))},
 //     {"Sha256", signingWithSha256()}
@@ -545,7 +545,7 @@
 
 BOOST_AUTO_TEST_CASE_TEMPLATE(VerifySignature, Dataset, SignatureDatasets)
 {
-  Dataset dataset;
+  const Dataset dataset;
   Certificate cert(Block(dataset.cert.data(), dataset.cert.size()));
   Buffer keyRaw = cert.getPublicKey();
   transform::PublicKey key;
@@ -630,7 +630,7 @@
 
 BOOST_AUTO_TEST_CASE_TEMPLATE(VerifyDigest, Dataset, DigestDatasets)
 {
-  Dataset dataset;
+  const Dataset dataset;
   Data data(Block(dataset.goodData.data(), dataset.goodData.size()));
   Data badSigData(Block(dataset.badSigData.data(), dataset.badSigData.size()));
   Interest interest(Block(dataset.goodInterest.data(), dataset.goodInterest.size()));
@@ -641,15 +641,8 @@
                                          dataset.badSigInterestOldFormat.size()));
 
   BOOST_CHECK(verifySignature(data, nullopt));
-  BOOST_CHECK(verifyDigest(data, DigestAlgorithm::SHA256));
   BOOST_CHECK(verifySignature(interest, nullopt));
-  BOOST_CHECK(verifyDigest(interest, DigestAlgorithm::SHA256));
   BOOST_CHECK(verifySignature(interestOldFormat, nullopt));
-  BOOST_CHECK(verifyDigest(interestOldFormat, DigestAlgorithm::SHA256));
-
-  BOOST_CHECK(!verifyDigest(badSigData, DigestAlgorithm::SHA256));
-  BOOST_CHECK(!verifyDigest(badSigInterest, DigestAlgorithm::SHA256));
-  BOOST_CHECK(!verifyDigest(badSigInterestOldFormat, DigestAlgorithm::SHA256));
 
   BOOST_CHECK(!verifySignature(badSigData, nullopt));
   BOOST_CHECK(!verifySignature(badSigInterest, nullopt));
@@ -661,15 +654,9 @@
   Interest unsignedInterest2("/interest-with-one-name-component");
   unsignedInterest2.setCanBePrefix(false);
 
-  BOOST_CHECK(!verifyDigest(unsignedData, DigestAlgorithm::SHA256));
-  BOOST_CHECK(!verifyDigest(unsignedInterest1, DigestAlgorithm::SHA256));
-  BOOST_CHECK(!verifyDigest(unsignedInterest2, DigestAlgorithm::SHA256));
-
   BOOST_CHECK(!verifySignature(unsignedData, nullopt));
   BOOST_CHECK(!verifySignature(unsignedInterest1, nullopt));
   BOOST_CHECK(!verifySignature(unsignedInterest2, nullopt));
-
-  // - base version of verifyDigest is tested transitively
 }
 
 const uint8_t sha256DataUnrecognizedElements[] = {
@@ -696,8 +683,8 @@
   Data data(Block(sha256DataUnrecognizedElements, sizeof(sha256DataUnrecognizedElements)));
   Interest interest(Block(sha256InterestUnrecognizedElements, sizeof(sha256InterestUnrecognizedElements)));
 
-  BOOST_CHECK(verifyDigest(data, DigestAlgorithm::SHA256));
-  BOOST_CHECK(verifyDigest(interest, DigestAlgorithm::SHA256));
+  BOOST_CHECK(verifySignature(data, nullopt));
+  BOOST_CHECK(verifySignature(interest, nullopt));
 }
 
 BOOST_AUTO_TEST_SUITE_END() // TestVerificationHelpers