util: FaceUri canonization for udp,tcp,ether

refs #1994

Change-Id: I5349d999a3dd52a1fe533e17766d70df5e67091f
diff --git a/src/util/face-uri.cpp b/src/util/face-uri.cpp
index e5f9611..ff5669b 100644
--- a/src/util/face-uri.cpp
+++ b/src/util/face-uri.cpp
@@ -26,10 +26,14 @@
  */
 
 #include "face-uri.hpp"
+#include "dns.hpp"
 
+#include <set>
 #include <boost/concept_check.hpp>
 #include <boost/regex.hpp>
 #include <boost/lexical_cast.hpp>
+#include <boost/mpl/vector.hpp>
+#include <boost/mpl/for_each.hpp>
 
 namespace ndn {
 namespace util {
@@ -202,5 +206,340 @@
   return os;
 }
 
+/** \brief a CanonizeProvider provides FaceUri canonization functionality for a group of schemes
+ */
+class CanonizeProvider : noncopyable
+{
+public:
+  virtual
+  ~CanonizeProvider()
+  {
+  }
+
+  virtual std::set<std::string>
+  getSchemes() const = 0;
+
+  virtual bool
+  isCanonical(const FaceUri& faceUri) const = 0;
+
+  virtual void
+  canonize(const FaceUri& faceUri,
+           const FaceUri::CanonizeSuccessCallback& onSuccess,
+           const FaceUri::CanonizeFailureCallback& onFailure,
+           boost::asio::io_service& io, const time::nanoseconds& timeout) const = 0;
+};
+
+template<typename Protocol>
+class IpHostCanonizeProvider : public CanonizeProvider
+{
+public:
+  virtual std::set<std::string>
+  getSchemes() const
+  {
+    std::set<std::string> schemes;
+    schemes.insert(m_baseScheme);
+    schemes.insert(m_v4Scheme);
+    schemes.insert(m_v6Scheme);
+    return schemes;
+  }
+
+  virtual bool
+  isCanonical(const FaceUri& faceUri) const
+  {
+    if (faceUri.getPort().empty()) {
+      return false;
+    }
+    if (!faceUri.getPath().empty()) {
+      return false;
+    }
+
+    boost::system::error_code ec;
+    boost::asio::ip::address addr;
+    if (faceUri.getScheme() == m_v4Scheme) {
+      addr = boost::asio::ip::address_v4::from_string(faceUri.getHost(), ec);
+    }
+    else if (faceUri.getScheme() == m_v6Scheme) {
+      addr = boost::asio::ip::address_v6::from_string(faceUri.getHost(), ec);
+    }
+    else {
+      return false;
+    }
+    return !static_cast<bool>(ec) && addr.to_string() == faceUri.getHost() &&
+           this->checkAddress(addr).first;
+  }
+
+  virtual void
+  canonize(const FaceUri& faceUri,
+           const FaceUri::CanonizeSuccessCallback& onSuccess,
+           const FaceUri::CanonizeFailureCallback& onFailure,
+           boost::asio::io_service& io, const time::nanoseconds& timeout) const
+  {
+    if (this->isCanonical(faceUri)) {
+      onSuccess(faceUri);
+      return;
+    }
+
+    dns::AddressSelector addressSelector;
+    if (faceUri.getScheme() == m_v4Scheme) {
+      addressSelector = dns::Ipv4Only();
+    }
+    else if (faceUri.getScheme() == m_v6Scheme) {
+      addressSelector = dns::Ipv6Only();
+    }
+    else {
+      BOOST_ASSERT(faceUri.getScheme() == m_baseScheme);
+      addressSelector = dns::AnyAddress();
+    }
+
+    // make a copy because caller may modify faceUri
+    shared_ptr<FaceUri> uri = make_shared<FaceUri>(faceUri);
+    dns::asyncResolve(faceUri.getHost(),
+      bind(&IpHostCanonizeProvider<Protocol>::onDnsSuccess, this, uri, onSuccess, onFailure, _1),
+      bind(&IpHostCanonizeProvider<Protocol>::onDnsFailure, this, uri, onFailure, _1),
+      io, addressSelector, timeout);
+  }
+
+protected:
+  IpHostCanonizeProvider(const std::string& baseScheme,
+                         uint32_t defaultUnicastPort = 6363,
+                         uint32_t defaultMulticastPort = 56363)
+    : m_baseScheme(baseScheme)
+    , m_v4Scheme(baseScheme + "4")
+    , m_v6Scheme(baseScheme + "6")
+    , m_defaultUnicastPort(defaultUnicastPort)
+    , m_defaultMulticastPort(defaultMulticastPort)
+  {
+  }
+
+private:
+  // faceUri is a shared_ptr passed by value because this function can take ownership
+  void
+  onDnsSuccess(shared_ptr<FaceUri> faceUri,
+               const FaceUri::CanonizeSuccessCallback& onSuccess,
+               const FaceUri::CanonizeFailureCallback& onFailure,
+               const dns::IpAddress& ipAddress) const
+  {
+    std::pair<bool, std::string> checkAddressRes = this->checkAddress(ipAddress);
+    if (!checkAddressRes.first) {
+      onFailure(checkAddressRes.second);
+      return;
+    }
+
+    uint32_t port = 0;
+    if (faceUri->getPort().empty()) {
+      port = ipAddress.is_multicast() ? m_defaultMulticastPort : m_defaultUnicastPort;
+    }
+    else {
+      try {
+        port = boost::lexical_cast<uint32_t>(faceUri->getPort());
+      }
+      catch (boost::bad_lexical_cast&) {
+        onFailure("invalid port number");
+        return;
+      }
+    }
+
+    FaceUri canonicalUri(typename Protocol::endpoint(ipAddress, port));
+    BOOST_ASSERT(canonicalUri.isCanonical());
+    onSuccess(canonicalUri);
+  }
+
+  // faceUri is a shared_ptr passed by value because this function can take ownership
+  void
+  onDnsFailure(shared_ptr<FaceUri> faceUri, const FaceUri::CanonizeFailureCallback& onFailure,
+               const std::string& reason) const
+  {
+    onFailure(reason);
+  }
+
+  /** \brief when overriden in a subclass, check the IP address is allowable
+   *  \return (true,ignored) if the address is allowable;
+   *          (false,reason) if the address is not allowable.
+   */
+  virtual std::pair<bool, std::string>
+  checkAddress(const dns::IpAddress& ipAddress) const
+  {
+    return std::make_pair(true, "");
+  }
+
+private:
+  std::string m_baseScheme;
+  std::string m_v4Scheme;
+  std::string m_v6Scheme;
+  uint32_t m_defaultUnicastPort;
+  uint32_t m_defaultMulticastPort;
+};
+
+class UdpCanonizeProvider : public IpHostCanonizeProvider<boost::asio::ip::udp>
+{
+public:
+  UdpCanonizeProvider()
+    : IpHostCanonizeProvider("udp")
+  {
+  }
+
+protected:
+  // checkAddress is not overriden:
+  // Although NFD doesn't support IPv6 multicast, it's an implementation limitation.
+  // FaceMgmt protocol allows IPv6 multicast address in UDP.
+};
+
+class TcpCanonizeProvider : public IpHostCanonizeProvider<boost::asio::ip::tcp>
+{
+public:
+public:
+  TcpCanonizeProvider()
+    : IpHostCanonizeProvider("tcp")
+  {
+  }
+
+protected:
+  virtual std::pair<bool, std::string>
+  checkAddress(const dns::IpAddress& ipAddress) const
+  {
+    if (ipAddress.is_multicast()) {
+      return std::make_pair(false, "cannot use multicast address");
+    }
+    return std::make_pair(true, "");
+  }
+};
+
+class EtherCanonizeProvider : public CanonizeProvider
+{
+public:
+  virtual std::set<std::string>
+  getSchemes() const
+  {
+    std::set<std::string> schemes;
+    schemes.insert("ether");
+    return schemes;
+  }
+
+  virtual bool
+  isCanonical(const FaceUri& faceUri) const
+  {
+    if (!faceUri.getPort().empty()) {
+      return false;
+    }
+    if (!faceUri.getPath().empty()) {
+      return false;
+    }
+
+    ethernet::Address addr = ethernet::Address::fromString(faceUri.getHost());
+    return addr.toString() == faceUri.getHost();
+  }
+
+  virtual void
+  canonize(const FaceUri& faceUri,
+           const FaceUri::CanonizeSuccessCallback& onSuccess,
+           const FaceUri::CanonizeFailureCallback& onFailure,
+           boost::asio::io_service& io, const time::nanoseconds& timeout) const
+  {
+    ethernet::Address addr = ethernet::Address::fromString(faceUri.getHost());
+    if (addr.isNull()) {
+      onFailure("cannot parse address");
+      return;
+    }
+
+    FaceUri canonicalUri(addr);
+    BOOST_ASSERT(canonicalUri.isCanonical());
+    onSuccess(canonicalUri);
+  }
+};
+
+typedef boost::mpl::vector<
+    UdpCanonizeProvider*,
+    TcpCanonizeProvider*,
+    EtherCanonizeProvider*
+  > CanonizeProviders;
+typedef std::map<std::string, shared_ptr<CanonizeProvider> > CanonizeProviderTable;
+
+class CanonizeProviderTableInitializer
+{
+public:
+  explicit
+  CanonizeProviderTableInitializer(CanonizeProviderTable& providerTable)
+    : m_providerTable(providerTable)
+  {
+  }
+
+  template<typename CP> void
+  operator()(CP*)
+  {
+    shared_ptr<CanonizeProvider> cp = make_shared<CP>();
+
+    std::set<std::string> schemes = cp->getSchemes();
+    BOOST_ASSERT(!schemes.empty());
+    for (std::set<std::string>::iterator it = schemes.begin();
+         it != schemes.end(); ++it) {
+      BOOST_ASSERT(m_providerTable.count(*it) == 0);
+      m_providerTable[*it] = cp;
+    }
+  }
+
+private:
+  CanonizeProviderTable& m_providerTable;
+};
+
+static const CanonizeProvider*
+getCanonizeProvider(const std::string& scheme)
+{
+  static CanonizeProviderTable providerTable;
+  if (providerTable.empty()) {
+    boost::mpl::for_each<CanonizeProviders>(CanonizeProviderTableInitializer(providerTable));
+    BOOST_ASSERT(!providerTable.empty());
+  }
+
+  CanonizeProviderTable::const_iterator it = providerTable.find(scheme);
+  if (it == providerTable.end()) {
+    return 0;
+  }
+  return it->second.get();
+}
+
+bool
+FaceUri::canCanonize(const std::string& scheme)
+{
+  return getCanonizeProvider(scheme) != 0;
+}
+
+bool
+FaceUri::isCanonical() const
+{
+  const CanonizeProvider* cp = getCanonizeProvider(this->getScheme());
+  if (cp == 0) {
+    return false;
+  }
+
+  return cp->isCanonical(*this);
+}
+
+static inline void
+nop()
+{
+}
+
+void
+FaceUri::canonize(const CanonizeSuccessCallback& onSuccess,
+                  const CanonizeFailureCallback& onFailure,
+                  boost::asio::io_service& io, const time::nanoseconds& timeout) const
+{
+  const CanonizeProvider* cp = getCanonizeProvider(this->getScheme());
+  if (cp == 0) {
+    if (static_cast<bool>(onFailure)) {
+      onFailure("scheme not supported");
+    }
+    return;
+  }
+
+  static CanonizeSuccessCallback successNop = bind(&nop);
+  static CanonizeFailureCallback failureNop = bind(&nop);
+
+  cp->canonize(*this,
+               static_cast<bool>(onSuccess) ? onSuccess : successNop,
+               static_cast<bool>(onFailure) ? onFailure : failureNop,
+               io, timeout);
+}
+
 } // namespace util
 } // namespace ndn
diff --git a/src/util/face-uri.hpp b/src/util/face-uri.hpp
index f2786e1..95d2c87 100644
--- a/src/util/face-uri.hpp
+++ b/src/util/face-uri.hpp
@@ -33,6 +33,7 @@
 #include <boost/asio/ip/tcp.hpp>
 #include <boost/asio/local/stream_protocol.hpp>
 #include "ethernet.hpp"
+#include "time.hpp"
 
 namespace ndn {
 namespace util {
@@ -142,6 +143,36 @@
   bool
   operator!=(const FaceUri& rhs) const;
 
+public: // canonical FaceUri
+  /** \return whether a FaceUri of the scheme can be canonized
+   */
+  static bool
+  canCanonize(const std::string& scheme);
+
+  /** \brief determine whether this FaceUri is in canonical form
+   *  \return true if this FaceUri is in canonical form,
+   *          false if this FaceUri is not in canonical form or
+   *          or it's undetermined whether this FaceUri is in canonical form
+   */
+  bool
+  isCanonical() const;
+
+  typedef function<void(const FaceUri&)> CanonizeSuccessCallback;
+  typedef function<void(const std::string& reason)> CanonizeFailureCallback;
+
+  /** \brief asynchronously convert this FaceUri to canonical form
+   *  \param onSuccess function to call after this FaceUri is converted to canonical form
+   *  \note A new FaceUri in canonical form will be created; this FaceUri is unchanged.
+   *  \param onFailure function to call if this FaceUri cannot be converted to canonical form
+   *  \param timeout maximum allowable duration of the operations.
+   *                 It's intentional not to provide a default value: the caller should set
+   *                 a reasonable value in balance between network delay and user experience.
+   */
+  void
+  canonize(const CanonizeSuccessCallback& onSuccess,
+           const CanonizeFailureCallback& onFailure,
+           boost::asio::io_service& io, const time::nanoseconds& timeout) const;
+
 private:
   std::string m_scheme;
   std::string m_host;