security: Add base64 and hex encoding/decoding support in transformation
Change-Id: I11d5c8921abcf04411aac38382dc285269f553ef
Refs: #3009
diff --git a/src/security/transform/base64-encode.cpp b/src/security/transform/base64-encode.cpp
new file mode 100644
index 0000000..0a27bed
--- /dev/null
+++ b/src/security/transform/base64-encode.cpp
@@ -0,0 +1,135 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/**
+ * Copyright (c) 2013-2016 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 "base64-encode.hpp"
+#include "../../encoding/buffer.hpp"
+#include "../detail/openssl.hpp"
+
+namespace ndn {
+namespace security {
+namespace transform {
+
+/**
+ * @brief The implementation class which contains the internal state of the filter
+ * which includes openssl specific structures.
+ */
+class Base64Encode::Impl
+{
+public:
+ Impl()
+ : m_base64(BIO_new(BIO_f_base64()))
+ , m_sink(BIO_new(BIO_s_mem()))
+ {
+ // connect base64 transform to the data sink.
+ BIO_push(m_base64, m_sink);
+ }
+
+ ~Impl()
+ {
+ BIO_free_all(m_sink);
+ }
+
+public:
+ BIO* m_base64;
+ BIO* m_sink; // BIO_f_base64 alone does not work without a sink
+};
+
+Base64Encode::Base64Encode(bool needBreak)
+ : m_impl(new Impl)
+{
+ if (!needBreak)
+ BIO_set_flags(m_impl->m_base64, BIO_FLAGS_BASE64_NO_NL);
+}
+
+void
+Base64Encode::preTransform()
+{
+ fillOutputBuffer();
+}
+
+size_t
+Base64Encode::convert(const uint8_t* data, size_t dataLen)
+{
+ if (dataLen == 0)
+ return 0;
+
+ int wLen = BIO_write(m_impl->m_base64, data, dataLen);
+
+ if (wLen <= 0) { // fail to write data
+ if (!BIO_should_retry(m_impl->m_base64)) {
+ // we haven't written everything but some error happens, and we cannot retry
+ BOOST_THROW_EXCEPTION(Error(getIndex(), "Failed to accept more input"));
+ }
+ return 0;
+ }
+ else { // update number of bytes written
+ fillOutputBuffer();
+ return wLen;
+ }
+}
+
+void
+Base64Encode::finalize()
+{
+ if (BIO_flush(m_impl->m_base64) != 1)
+ BOOST_THROW_EXCEPTION(Error(getIndex(), "Failed to flush"));
+
+ while (!isConverterEmpty()) {
+ fillOutputBuffer();
+ while (!isOutputBufferEmpty()) {
+ flushOutputBuffer();
+ }
+ }
+}
+
+void
+Base64Encode::fillOutputBuffer()
+{
+ int nRead = BIO_pending(m_impl->m_sink);
+ if (nRead <= 0)
+ return;
+
+ // there is something to read from BIO
+ auto buffer = make_unique<OBuffer>(nRead);
+ int rLen = BIO_read(m_impl->m_sink, &(*buffer)[0], nRead);
+ if (rLen < 0)
+ return;
+
+ if (rLen < nRead)
+ buffer->erase(buffer->begin() + rLen, buffer->end());
+ setOutputBuffer(std::move(buffer));
+}
+
+bool
+Base64Encode::isConverterEmpty()
+{
+ return (BIO_pending(m_impl->m_sink) <= 0);
+}
+
+unique_ptr<Transform>
+base64Encode(bool needBreak)
+{
+ return make_unique<Base64Encode>(needBreak);
+}
+
+} // namespace transform
+} // namespace security
+} // namespace ndn