net: support link-local IPv6 addresses in FaceUri

Change-Id: Ia986847e60b0a21a94bf2e4ce99d4a5a688a2006
Refs: #1428
diff --git a/src/net/address-converter.cpp b/src/net/address-converter.cpp
new file mode 100644
index 0000000..b6f2de2
--- /dev/null
+++ b/src/net/address-converter.cpp
@@ -0,0 +1,151 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/*
+ * Copyright (c) 2013-2017 Regents of the University of California,
+ *                         Arizona Board of Regents,
+ *                         Colorado State University,
+ *                         University Pierre & Marie Curie, Sorbonne University,
+ *                         Washington University in St. Louis,
+ *                         Beijing Institute of Technology,
+ *                         The University of Memphis.
+ *
+ * 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 "address-converter.hpp"
+
+#if BOOST_VERSION < 105800
+#include <boost/algorithm/string.hpp>
+#include <boost/lexical_cast.hpp>
+#include <vector>
+#endif // BOOST_VERSION < 105800
+
+#include <net/if.h> // for if_nametoindex and if_indextoname
+
+namespace ndn {
+namespace ip {
+
+optional<std::string>
+scopeNameFromId(unsigned int scopeId)
+{
+  char buffer[IFNAMSIZ];
+  auto scopeName = if_indextoname(scopeId, buffer);
+  if (scopeName != nullptr) {
+    return std::string(scopeName);
+  }
+  return nullopt;
+}
+
+#if BOOST_VERSION < 105800
+static unsigned int
+scopeIdFromString(const std::string& scope)
+{
+  auto id = if_nametoindex(scope.c_str());
+  if (id != 0) {
+    return id;
+  }
+
+  // cannot find a corresponding index, assume it's not a name but an interface index
+  try {
+    return boost::lexical_cast<unsigned int>(scope);
+  }
+  catch (const boost::bad_lexical_cast&) {
+    return 0;
+  }
+}
+
+struct ParsedAddress
+{
+  boost::asio::ip::address addr;
+  std::string scope;
+};
+
+static ParsedAddress
+parseAddressFromString(const std::string& address, boost::system::error_code& ec)
+{
+  std::vector<std::string> parseResult;
+  boost::algorithm::split(parseResult, address, boost::is_any_of("%"));
+  auto addr = boost::asio::ip::address::from_string(parseResult[0], ec);
+
+  switch (parseResult.size()) {
+  case 1:
+    // regular address
+    return {addr, ""};
+  case 2:
+    // the presence of % in either an IPv4 address or a regular IPv6 address is invalid
+    if (!ec && addr.is_v6() && addr.to_v6().is_link_local()) {
+      return {addr, parseResult[1]};
+    }
+    // Fallthrough, if the presence of % is invalid set ec to invalid_argument
+  default:
+    ec = boost::asio::error::invalid_argument;
+    return {};
+  }
+}
+#endif // BOOST_VERSION < 105800
+
+boost::asio::ip::address
+addressFromString(const std::string& address, boost::system::error_code& ec)
+{
+  // boost < 1.58 cannot recognize scope-id in link-local IPv6 address
+#if BOOST_VERSION < 105800
+  auto parsedAddress = parseAddressFromString(address, ec);
+  if (ec || parsedAddress.addr.is_v4()) {
+    return parsedAddress.addr;
+  }
+  auto addr = parsedAddress.addr.to_v6();
+  addr.scope_id(scopeIdFromString(parsedAddress.scope));
+  return addr;
+#else
+  return boost::asio::ip::address::from_string(address, ec);
+#endif // BOOST_VERSION < 105800
+}
+
+boost::asio::ip::address
+addressFromString(const std::string& address)
+{
+  boost::system::error_code ec;
+  auto addr = addressFromString(address, ec);
+  if (ec) {
+    BOOST_THROW_EXCEPTION(boost::system::system_error(ec));
+  }
+  return addr;
+}
+
+boost::asio::ip::address_v6
+addressV6FromString(const std::string& address, boost::system::error_code& ec)
+{
+  auto addr = addressFromString(address, ec);
+  if (ec || addr.is_v4()) {
+    ec = boost::asio::error::invalid_argument;
+    return {};
+  }
+  return addr.to_v6();
+}
+
+boost::asio::ip::address_v6
+addressV6FromString(const std::string& address)
+{
+  boost::system::error_code ec;
+  auto addr = addressV6FromString(address, ec);
+  if (ec) {
+    BOOST_THROW_EXCEPTION(boost::system::system_error(ec));
+  }
+  return addr;
+}
+
+} // namespace ip
+} // namespace ndn