util: rename digest.hpp to sha256.hpp
The new file name matches the Sha256 class included within.
This commit also deletes deprecated crypto.hpp.
refs #3940
Change-Id: Ib9bbcd0ba087b812bb0886ceaea116689d4633f5
diff --git a/src/util/sha256.hpp b/src/util/sha256.hpp
new file mode 100644
index 0000000..d729e90
--- /dev/null
+++ b/src/util/sha256.hpp
@@ -0,0 +1,184 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/*
+ * Copyright (c) 2013-2017 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.
+ */
+
+#ifndef NDN_UTIL_SHA256_HPP
+#define NDN_UTIL_SHA256_HPP
+
+#include "../encoding/block.hpp"
+#include "../encoding/buffer-stream.hpp"
+#include "../security/transform/step-source.hpp"
+
+namespace ndn {
+namespace util {
+
+/**
+ * @brief Provides stateful SHA-256 digest calculation.
+ *
+ * Example:
+ * @code
+ * Sha256 digest;
+ * digest.update(buf1, size1);
+ * digest.update(buf2, size2);
+ * ...
+ * ConstBufferPtr result = digest.computeDigest();
+ * @endcode
+ */
+class Sha256
+{
+public:
+ class Error : public std::runtime_error
+ {
+ public:
+ explicit
+ Error(const std::string& what)
+ : std::runtime_error(what)
+ {
+ }
+ };
+
+ /**
+ * @brief Length in bytes of a SHA-256 digest.
+ */
+ static const size_t DIGEST_SIZE = 32;
+
+ /**
+ * @brief Create an empty SHA-256 digest.
+ */
+ Sha256();
+
+ /**
+ * @brief Calculate SHA-256 digest of the input stream @p is.
+ */
+ explicit
+ Sha256(std::istream& is);
+
+ /**
+ * @brief Check if digest is empty.
+ *
+ * An empty digest means nothing has been taken into calculation.
+ */
+ bool
+ empty() const
+ {
+ return m_isEmpty;
+ }
+
+ /**
+ * @brief Discard the current state and start a new digest calculation.
+ */
+ void
+ reset();
+
+ /**
+ * @brief Finalize and return the digest based on all previously supplied inputs.
+ */
+ ConstBufferPtr
+ computeDigest();
+
+ /**
+ * @brief Check if the supplied digest is equal to this digest.
+ * @note This method invokes computeDigest() on both operands, finalizing the digest.
+ */
+ bool
+ operator==(Sha256& digest);
+
+ /**
+ * @brief Check if the supplied digest is not equal to this digest.
+ * @note This method invokes computeDigest() on both operands, finalizing the digest.
+ */
+ bool
+ operator!=(Sha256& digest)
+ {
+ return !(*this == digest);
+ }
+
+ /**
+ * @brief Add existing digest to the digest calculation.
+ * @param src digest to combine with
+ *
+ * The result of this combination is `sha256(sha256(...))`
+ *
+ * @note This method invokes computeDigest() on @p src, finalizing the digest.
+ * @throw Error the digest has already been finalized
+ */
+ Sha256&
+ operator<<(Sha256& src);
+
+ /**
+ * @brief Add a string to the digest calculation.
+ * @throw Error the digest has already been finalized
+ */
+ Sha256&
+ operator<<(const std::string& str);
+
+ /**
+ * @brief Add a block to the digest calculation.
+ * @throw Error the digest has already been finalized
+ */
+ Sha256&
+ operator<<(const Block& block);
+
+ /**
+ * @brief Add a uint64_t value to the digest calculation.
+ * @throw Error the digest has already been finalized
+ */
+ Sha256&
+ operator<<(uint64_t value);
+
+ /**
+ * @brief Add a raw buffer to the digest calculation.
+ * @param buffer the input buffer
+ * @param size the size of the input buffer
+ * @throw Error the digest has already been finalized
+ */
+ void
+ update(const uint8_t* buffer, size_t size);
+
+ /**
+ * @brief Convert digest to std::string.
+ * @note This method invokes computeDigest(), finalizing the digest.
+ */
+ std::string
+ toString();
+
+ /**
+ * @brief Stateless SHA-256 digest calculation.
+ * @param buffer the input buffer
+ * @param size the size of the input buffer
+ * @return SHA-256 digest of the input buffer
+ */
+ static ConstBufferPtr
+ computeDigest(const uint8_t* buffer, size_t size);
+
+private:
+ unique_ptr<security::transform::StepSource> m_input;
+ unique_ptr<OBufferStream> m_output;
+ bool m_isEmpty;
+ bool m_isFinalized;
+};
+
+std::ostream&
+operator<<(std::ostream& os, Sha256& digest);
+
+} // namespace util
+} // namespace ndn
+
+#endif // NDN_UTIL_SHA256_HPP