diff --git a/tests/unit-tests/util/test-digest.cpp b/tests/unit-tests/util/test-digest.cpp
new file mode 100644
index 0000000..e38dad2
--- /dev/null
+++ b/tests/unit-tests/util/test-digest.cpp
@@ -0,0 +1,187 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/**
+ * Copyright (c) 2013-2014 Regents of the University of California.
+ *
+ * This file is part of ndn-cxx library (NDN C++ library with eXperimental eXtensions).
+ *
+ * ndn-cxx library is free software: you can redistribute it and/or modify it under the
+ * terms of the GNU Lesser General Public License as published by the Free Software
+ * Foundation, either version 3 of the License, or (at your option) any later version.
+ *
+ * ndn-cxx library is distributed in the hope that it will be useful, but WITHOUT ANY
+ * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
+ * PARTICULAR PURPOSE.  See the GNU Lesser General Public License for more details.
+ *
+ * You should have received copies of the GNU General Public License and GNU Lesser
+ * General Public License along with ndn-cxx, e.g., in COPYING.md file.  If not, see
+ * <http://www.gnu.org/licenses/>.
+ *
+ * See AUTHORS.md for complete list of ndn-cxx authors and contributors.
+ */
+
+#include "util/digest.hpp"
+#include "util/crypto.hpp"
+
+#include "boost-test.hpp"
+
+namespace ndn {
+namespace util {
+namespace test {
+
+BOOST_AUTO_TEST_SUITE(UtilTestDigest)
+
+BOOST_AUTO_TEST_CASE(Sha256Digest)
+{
+  uint8_t origin[4] = {0x01, 0x02, 0x03, 0x04};
+  ConstBufferPtr digest1 = crypto::sha256(origin, 4);
+
+  Sha256 statefulSha256;
+  statefulSha256.update(origin, 1);
+  statefulSha256.update(origin + 1, 1);
+  statefulSha256.update(origin + 2, 1);
+  statefulSha256.update(origin + 3, 1);
+  ConstBufferPtr digest2 = statefulSha256.computeDigest();
+
+  BOOST_CHECK_EQUAL_COLLECTIONS(digest1->buf(),
+                                digest1->buf() + digest1->size(),
+                                digest2->buf(),
+                                digest2->buf() + digest2->size());
+}
+
+BOOST_AUTO_TEST_CASE(Compare)
+{
+  uint8_t origin[4] = {0x01, 0x02, 0x03, 0x04};
+
+  Sha256 digest;
+  digest.update(origin, 4);
+  digest.computeDigest();
+
+  Sha256 digest2;
+  digest2.update(origin, 1);
+  digest2.update(origin + 1, 1);
+  digest2.update(origin + 2, 1);
+  digest2.update(origin + 3, 1);
+  digest2.computeDigest();
+
+  BOOST_CHECK(digest == digest2);
+  BOOST_CHECK_EQUAL(digest != digest2, false);
+}
+
+BOOST_AUTO_TEST_CASE(OperatorDigest)
+{
+  uint8_t origin[32] = {0x94, 0xEE, 0x05, 0x93, 0x35, 0xE5, 0x87, 0xE5,
+                        0x01, 0xCC, 0x4B, 0xF9, 0x06, 0x13, 0xE0, 0x81,
+                        0x4F, 0x00, 0xA7, 0xB0, 0x8B, 0xC7, 0xC6, 0x48,
+                        0xFD, 0x86, 0x5A, 0x2A, 0xF6, 0xA2, 0x2C, 0xC2};
+  ConstBufferPtr digest1 = crypto::sha256(origin, 32);
+
+  std::string str("TEST");
+  Sha256 metaDigest;
+  metaDigest << str;
+
+  Sha256 statefulSha256;
+  statefulSha256 << metaDigest;
+  ConstBufferPtr digest2 = statefulSha256.computeDigest();
+
+  BOOST_CHECK_EQUAL_COLLECTIONS(digest1->buf(),
+                                digest1->buf() + digest1->size(),
+                                digest2->buf(),
+                                digest2->buf() + digest2->size());
+}
+
+BOOST_AUTO_TEST_CASE(OperatorString)
+{
+  uint8_t origin[4] = {0x54, 0x45, 0x53, 0x54};
+  ConstBufferPtr digest1 = crypto::sha256(origin, 4);
+
+  std::string str("TEST");
+  Sha256 statefulSha256;
+  statefulSha256 << str;
+  ConstBufferPtr digest2 = statefulSha256.computeDigest();
+
+  BOOST_CHECK_EQUAL_COLLECTIONS(digest1->buf(),
+                                digest1->buf() + digest1->size(),
+                                digest2->buf(),
+                                digest2->buf() + digest2->size());
+}
+
+BOOST_AUTO_TEST_CASE(OperatorBlock)
+{
+  uint8_t origin[] = {
+    0x16, 0x1b, // SignatureInfo
+      0x1b, 0x01, // SignatureType
+        0x01, // Sha256WithRsa
+      0x1c, 0x16, // KeyLocator
+        0x07, 0x14, // Name
+          0x08, 0x04,
+            0x74, 0x65, 0x73, 0x74,
+          0x08, 0x03,
+            0x6b, 0x65, 0x79,
+          0x08, 0x07,
+            0x6c, 0x6f, 0x63, 0x61, 0x74, 0x6f, 0x72
+  };
+  ConstBufferPtr digest1 = crypto::sha256(origin, sizeof(origin));
+
+  Sha256 statefulSha256;
+  Block block(origin, sizeof(origin));
+  statefulSha256 << block;
+  ConstBufferPtr digest2 = statefulSha256.computeDigest();
+
+  BOOST_CHECK_EQUAL_COLLECTIONS(digest1->buf(),
+                                digest1->buf() + digest1->size(),
+                                digest2->buf(),
+                                digest2->buf() + digest2->size());
+}
+
+BOOST_AUTO_TEST_CASE(OperatorUint64t)
+{
+  uint64_t origin[4] = {1, 2, 3, 4};
+  ConstBufferPtr digest1 = crypto::sha256(reinterpret_cast<uint8_t*>(origin), 32);
+
+  Sha256 statefulSha256;
+  statefulSha256 << origin[0];
+  statefulSha256 << origin[1];
+  statefulSha256 << origin[2];
+  statefulSha256 << origin[3];
+  ConstBufferPtr digest2 = statefulSha256.computeDigest();
+
+  BOOST_CHECK_EQUAL_COLLECTIONS(digest1->buf(),
+                                digest1->buf() + digest1->size(),
+                                digest2->buf(),
+                                digest2->buf() + digest2->size());
+}
+
+
+BOOST_AUTO_TEST_CASE(Error)
+{
+  uint64_t origin = 256;
+
+  Sha256 digest;
+  BOOST_CHECK(digest.empty());
+
+  digest << origin;
+
+  BOOST_CHECK_NO_THROW(digest.computeDigest());
+  BOOST_CHECK_THROW(digest << origin, Sha256::Error);
+
+  digest.reset();
+}
+
+BOOST_AUTO_TEST_CASE(ComputeDigest)
+{
+  uint8_t origin[4] = {0x01, 0x02, 0x03, 0x04};
+  ConstBufferPtr digest1 = crypto::sha256(origin, 4);
+
+  ConstBufferPtr digest2 = Sha256::computeDigest(origin, 4);
+
+  BOOST_CHECK_EQUAL_COLLECTIONS(digest1->buf(),
+                                digest1->buf() + digest1->size(),
+                                digest2->buf(),
+                                digest2->buf() + digest2->size());
+}
+
+BOOST_AUTO_TEST_SUITE_END()
+
+} // namespace test
+} // namespace util
+} // namespace ndn