mgmt: encode and decode prefix announcement object

refs #4650

Change-Id: Ie8de492aac1ea9fd51ddc6b50f239913989abe72
diff --git a/src/prefix-announcement.cpp b/src/prefix-announcement.cpp
new file mode 100644
index 0000000..6149526
--- /dev/null
+++ b/src/prefix-announcement.cpp
@@ -0,0 +1,119 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/*
+ * Copyright (c) 2013-2018 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 "prefix-announcement.hpp"
+#include "encoding/tlv-nfd.hpp"
+
+#include <boost/lexical_cast.hpp>
+
+namespace ndn {
+
+static const name::Component KEYWORD_PA_COMP = "20025041"_block;
+
+PrefixAnnouncement::PrefixAnnouncement() = default;
+
+PrefixAnnouncement::PrefixAnnouncement(Data data)
+  : m_data(std::move(data))
+{
+  if (m_data->getContentType() != tlv::ContentType_PrefixAnn) {
+    BOOST_THROW_EXCEPTION(Error("Data is not a prefix announcement: ContentType is " +
+                                boost::lexical_cast<std::string>(m_data->getContentType())));
+  }
+
+  const Name& dataName = m_data->getName();
+  if (dataName.size() < 3 || dataName[-3] != KEYWORD_PA_COMP ||
+      !dataName[-2].isVersion() || !dataName[-1].isSegment()) {
+    BOOST_THROW_EXCEPTION(Error("Data is not a prefix announcement: wrong name structure"));
+  }
+  m_announcedName = dataName.getPrefix(-3);
+
+  const Block& payload = m_data->getContent();
+  payload.parse();
+
+  m_expiration = time::milliseconds(readNonNegativeInteger(payload.get(tlv::nfd::ExpirationPeriod)));
+
+  auto validityElement = payload.find(tlv::ValidityPeriod);
+  if (validityElement != payload.elements_end()) {
+    m_validity.emplace(*validityElement);
+  }
+
+  for (const Block& element : payload.elements()) {
+    if (element.type() != tlv::nfd::ExpirationPeriod && element.type() != tlv::ValidityPeriod &&
+        tlv::isCriticalType(element.type())) {
+      BOOST_THROW_EXCEPTION(Error("unrecognized element of critical type " +
+                                  to_string(element.type())));
+    }
+  }
+}
+
+const Data&
+PrefixAnnouncement::toData(KeyChain& keyChain, const ndn::security::SigningInfo& si,
+                           optional<uint64_t> version) const
+{
+  if (!m_data) {
+    Name dataName = m_announcedName;
+    dataName.append(KEYWORD_PA_COMP);
+    dataName.appendVersion(version.value_or(time::toUnixTimestamp(time::system_clock::now()).count()));
+    dataName.appendSegment(0);
+    m_data.emplace(dataName);
+
+    Block content(tlv::Content);
+    content.push_back(makeNonNegativeIntegerBlock(tlv::nfd::ExpirationPeriod,
+                                                  m_expiration.count()));
+    if (m_validity) {
+      content.push_back(m_validity->wireEncode());
+    }
+    content.encode();
+    m_data->setContent(content);
+
+    keyChain.sign(*m_data, si);
+  }
+  return *m_data;
+}
+
+PrefixAnnouncement&
+PrefixAnnouncement::setAnnouncedName(Name name)
+{
+  m_data.reset();
+  m_announcedName = std::move(name);
+  return *this;
+}
+
+PrefixAnnouncement&
+PrefixAnnouncement::setExpiration(time::milliseconds expiration)
+{
+  if (expiration < 0_ms) {
+    BOOST_THROW_EXCEPTION(std::invalid_argument("expiration period is negative"));
+  }
+  m_data.reset();
+  m_expiration = expiration;
+  return *this;
+}
+
+PrefixAnnouncement&
+PrefixAnnouncement::setValidityPeriod(optional<security::ValidityPeriod> validity)
+{
+  m_data.reset();
+  m_validity = std::move(validity);
+  return *this;
+}
+
+} // namespace ndn
diff --git a/src/prefix-announcement.hpp b/src/prefix-announcement.hpp
new file mode 100644
index 0000000..d811230
--- /dev/null
+++ b/src/prefix-announcement.hpp
@@ -0,0 +1,128 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/*
+ * Copyright (c) 2013-2018 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_CXX_PREFIX_ANNOUNCEMENT_HPP
+#define NDN_CXX_PREFIX_ANNOUNCEMENT_HPP
+
+#include "security/v2/key-chain.hpp"
+
+namespace ndn {
+
+/** \brief A prefix announcement object that represents an application's intent of registering a
+ *         prefix toward itself.
+ *  \sa https://redmine.named-data.net/projects/nfd/wiki/PrefixAnnouncement
+ */
+class PrefixAnnouncement
+{
+public:
+  class Error : public tlv::Error
+  {
+  public:
+    using tlv::Error::Error;
+  };
+
+  /** \brief Construct an empty prefix announcement.
+   *  \post getData() == nullopt
+   *  \post getAnnouncedName() == "/"
+   *  \post getExpiration() == 0_ms
+   */
+  PrefixAnnouncement();
+
+  /** \brief Decode a prefix announcement from Data.
+   *  \throw tlv::Error the Data is not a prefix announcement.
+   *  \post getData() == data
+   */
+  explicit
+  PrefixAnnouncement(Data data);
+
+  /** \brief Get the Data representing the prefix announcement, if available.
+   */
+  const optional<Data>&
+  getData() const
+  {
+    return m_data;
+  }
+
+  /** \brief Create a Data packet representing the prefix announcement, if it does not exist.
+   *  \param keyChain KeyChain to sign the Data.
+   *  \param si signing parameters.
+   *  \param version version number in Data name; if nullopt, use current Unix timestamp (in
+   *                 milliseconds) as the version number.
+   *  \post getData() == the returned Data
+   */
+  const Data&
+  toData(KeyChain& keyChain,
+         const ndn::security::SigningInfo& si = KeyChain::getDefaultSigningInfo(),
+         optional<uint64_t> version = nullopt) const;
+
+  /** \brief Return announced name.
+   */
+  const Name&
+  getAnnouncedName() const
+  {
+    return m_announcedName;
+  }
+
+  /** \brief Set announced name.
+   *  \post getData() == nullopt
+   */
+  PrefixAnnouncement&
+  setAnnouncedName(Name name);
+
+  /** \brief Return relative expiration period.
+   */
+  time::milliseconds
+  getExpiration() const
+  {
+    return m_expiration;
+  }
+
+  /** \brief Set relative expiration period.
+   *  \throw std::invalid_argument expiration period is negative.
+   *  \post getData() == nullopt
+   */
+  PrefixAnnouncement&
+  setExpiration(time::milliseconds expiration);
+
+  /** \brief Return absolute validity period.
+   */
+  optional<security::ValidityPeriod>
+  getValidityPeriod() const
+  {
+    return m_validity;
+  }
+
+  /** \brief Set absolute validity period.
+   *  \post getData() == nullopt
+   */
+  PrefixAnnouncement&
+  setValidityPeriod(optional<security::ValidityPeriod> validity);
+
+private:
+  mutable optional<Data> m_data;
+  Name m_announcedName;
+  time::milliseconds m_expiration;
+  optional<security::ValidityPeriod> m_validity;
+};
+
+} // namespace ndn
+
+#endif // NDN_CXX_PREFIX_ANNOUNCEMENT_HPP
diff --git a/tests/unit-tests/prefix-announcement.t.cpp b/tests/unit-tests/prefix-announcement.t.cpp
new file mode 100644
index 0000000..1dff8f9
--- /dev/null
+++ b/tests/unit-tests/prefix-announcement.t.cpp
@@ -0,0 +1,202 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/*
+ * Copyright (c) 2013-2018 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 "prefix-announcement.hpp"
+#include "encoding/tlv-nfd.hpp"
+
+#include "boost-test.hpp"
+#include "identity-management-fixture.hpp"
+#include "make-interest-data.hpp"
+
+namespace ndn {
+namespace tests {
+
+BOOST_AUTO_TEST_SUITE(TestPrefixAnnouncement)
+
+static Data
+makePrefixAnnData()
+{
+  return Data(
+    "067A 071A announced-name=/net/example 08036E6574 08076578616D706C65"
+    "          keyword-prefix-ann=20025041 version=0802FD01 segment=08020000"
+    "     1403 content-type=prefix-ann 180105"
+    "     1530 expire in one hour 6D040036EE80"
+    "          validity FD00FD26 FD00FE0F323031383130333054303030303030"
+    "                            FD00FF0F323031383131323454323335393539"
+    "     1603 1B0100 signature"
+    "     1720 0000000000000000000000000000000000000000000000000000000000000000"_block);
+}
+
+BOOST_FIXTURE_TEST_CASE(Encode, IdentityManagementFixture)
+{
+  PrefixAnnouncement pa;
+  BOOST_CHECK(!pa.getData());
+  const Data& data0 = pa.toData(m_keyChain, signingWithSha256(), 5);
+  BOOST_CHECK_EQUAL(data0.getName(), "/32=PA/%FD%05/%00%00");
+  BOOST_REQUIRE(pa.getData());
+  BOOST_CHECK_EQUAL(*pa.getData(), data0);
+
+  pa.setAnnouncedName("/net/example");
+  BOOST_CHECK_THROW(pa.setExpiration(-1_ms), std::invalid_argument);
+  pa.setExpiration(1_h);
+  const Data& data1 = pa.toData(m_keyChain, signingWithSha256(), 1);
+  BOOST_CHECK_EQUAL(data1.getName(), "/net/example/32=PA/%FD%01/%00%00");
+  const Block& payload1 = data1.getContent();
+  payload1.parse();
+  BOOST_CHECK_EQUAL(readNonNegativeInteger(payload1.get(tlv::nfd::ExpirationPeriod)), 3600000);
+  BOOST_CHECK(payload1.find(tlv::ValidityPeriod) == payload1.elements_end());
+
+  pa.setValidityPeriod(security::ValidityPeriod(time::fromIsoString("20181030T000000"),
+                                                time::fromIsoString("20181124T235959")));
+  const Data& data2 = pa.toData(m_keyChain);
+  const Block& payload2 = data2.getContent();
+  payload2.parse();
+  BOOST_CHECK_EQUAL(readNonNegativeInteger(payload2.get(tlv::nfd::ExpirationPeriod)), 3600000);
+  BOOST_CHECK_EQUAL(payload2.get(tlv::ValidityPeriod),
+                    "FD00FD26 FD00FE0F323031383130333054303030303030"
+                    "         FD00FF0F323031383131323454323335393539"_block);
+}
+
+BOOST_AUTO_TEST_CASE(DecodeGood)
+{
+  Data data0 = makePrefixAnnData();
+  PrefixAnnouncement pa0(data0);
+  BOOST_CHECK_EQUAL(pa0.getAnnouncedName(), "/net/example");
+  BOOST_CHECK_EQUAL(pa0.getExpiration(), 1_h);
+  BOOST_CHECK(pa0.getValidityPeriod());
+  BOOST_CHECK_EQUAL(*pa0.getValidityPeriod(),
+                    security::ValidityPeriod(time::fromIsoString("20181030T000000"),
+                                             time::fromIsoString("20181124T235959")));
+
+  // reorder ExpirationPeriod and ValidityPeriod, unrecognized non-critical element
+  Data data1 = makePrefixAnnData();
+  Block payload1 = data1.getContent();
+  payload1.parse();
+  Block expirationElement = payload1.get(tlv::nfd::ExpirationPeriod);
+  payload1.remove(tlv::nfd::ExpirationPeriod);
+  payload1.push_back(expirationElement);
+  payload1.push_back("2000"_block);
+  payload1.encode();
+  data1.setContent(payload1);
+  PrefixAnnouncement pa1(data1);
+  BOOST_CHECK_EQUAL(pa1.getAnnouncedName(), "/net/example");
+  BOOST_CHECK_EQUAL(pa1.getExpiration(), 1_h);
+  BOOST_CHECK(pa1.getValidityPeriod());
+  BOOST_CHECK_EQUAL(*pa1.getValidityPeriod(),
+                    security::ValidityPeriod(time::fromIsoString("20181030T000000"),
+                                             time::fromIsoString("20181124T235959")));
+
+  // no ValidityPeriod
+  Data data2 = makePrefixAnnData();
+  Block payload2 = data2.getContent();
+  payload2.parse();
+  payload2.remove(tlv::ValidityPeriod);
+  payload2.encode();
+  data2.setContent(payload2);
+  PrefixAnnouncement pa2(data2);
+  BOOST_CHECK_EQUAL(pa2.getAnnouncedName(), "/net/example");
+  BOOST_CHECK_EQUAL(pa2.getExpiration(), 1_h);
+  BOOST_CHECK(!pa2.getValidityPeriod());
+}
+
+BOOST_AUTO_TEST_CASE(DecodeBad)
+{
+  // wrong ContentType
+  Data data0 = makePrefixAnnData();
+  data0.setContentType(tlv::ContentType_Blob);
+  BOOST_CHECK_THROW(PrefixAnnouncement pa0(data0), tlv::Error);
+
+  // Name has no "32=PA" keyword
+  Data data1 = makePrefixAnnData();
+  setNameComponent(data1, -3, name::Component::fromEscapedString("32=not-PA"));
+  BOOST_CHECK_THROW(PrefixAnnouncement pa1(data1), tlv::Error);
+
+  // Name has no version component
+  Data data2 = makePrefixAnnData();
+  setNameComponent(data2, -2, "not-version");
+  BOOST_CHECK_THROW(PrefixAnnouncement pa2(data2), tlv::Error);
+
+  // Name has no segment number component
+  Data data3 = makePrefixAnnData();
+  setNameComponent(data3, -2, "not-segment");
+  BOOST_CHECK_THROW(PrefixAnnouncement pa3(data3), tlv::Error);
+
+  // Content has no ExpirationPeriod element
+  Data data4 = makePrefixAnnData();
+  Block payload4 = data4.getContent();
+  payload4.parse();
+  payload4.remove(tlv::nfd::ExpirationPeriod);
+  payload4.encode();
+  data4.setContent(payload4);
+  BOOST_CHECK_THROW(PrefixAnnouncement pa4(data4), tlv::Error);
+
+  // ExpirationPeriod is malformed
+  Data data5 = makePrefixAnnData();
+  Block payload5 = data5.getContent();
+  payload5.parse();
+  payload5.remove(tlv::nfd::ExpirationPeriod);
+  payload5.push_back("6D03010101"_block);
+  payload5.encode();
+  data5.setContent(payload5);
+  BOOST_CHECK_THROW(PrefixAnnouncement pa5(data5), tlv::Error);
+
+  // ValidityPeriod is malformed
+  Data data6 = makePrefixAnnData();
+  Block payload6 = data6.getContent();
+  payload6.parse();
+  payload6.remove(tlv::ValidityPeriod);
+  payload6.push_back("FD00FD00"_block);
+  payload6.encode();
+  data6.setContent(payload6);
+  BOOST_CHECK_THROW(PrefixAnnouncement pa6(data6), tlv::Error);
+
+  // Content has unrecognized critical element
+  Data data7 = makePrefixAnnData();
+  Block payload7 = data7.getContent();
+  payload7.parse();
+  payload7.push_back("0200"_block);
+  payload7.encode();
+  data7.setContent(payload7);
+  BOOST_CHECK_THROW(PrefixAnnouncement pa7(data7), tlv::Error);
+}
+
+BOOST_AUTO_TEST_CASE(Modify)
+{
+  PrefixAnnouncement pa0(makePrefixAnnData());
+  BOOST_REQUIRE(pa0.getData());
+  BOOST_CHECK_EQUAL(*pa0.getData(), makePrefixAnnData());
+  pa0.setAnnouncedName("/com/example");
+  BOOST_CHECK(!pa0.getData());
+
+  PrefixAnnouncement pa1(makePrefixAnnData());
+  pa1.setExpiration(5_min);
+  BOOST_CHECK(!pa1.getData());
+
+  PrefixAnnouncement pa2(makePrefixAnnData());
+  pa2.setValidityPeriod(security::ValidityPeriod(time::fromIsoString("20180118T000000"),
+                                                 time::fromIsoString("20180212T235959")));
+  BOOST_CHECK(!pa2.getData());
+}
+
+BOOST_AUTO_TEST_SUITE_END() // TestPrefixAnnouncement
+
+} // namespace tests
+} // namespace ndn