security: Integrate fetching certificates using Certificate Bundle

Change-Id: Iebac12a5cb9d1f4aa12aad09e8ef27f5b90a5d90
Refs: #3891
diff --git a/src/security/v2/certificate-bundle-fetcher.cpp b/src/security/v2/certificate-bundle-fetcher.cpp
new file mode 100644
index 0000000..e2fdab9
--- /dev/null
+++ b/src/security/v2/certificate-bundle-fetcher.cpp
@@ -0,0 +1,230 @@
+/* -*- 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.
+ */
+
+#include "certificate-bundle-fetcher.hpp"
+#include "face.hpp"
+#include "util/logger.hpp"
+
+namespace ndn {
+namespace security {
+namespace v2 {
+
+NDN_LOG_INIT(ndn.security.v2.CertificateBundleFetcher);
+
+#define NDN_LOG_DEBUG_DEPTH(x) NDN_LOG_DEBUG(std::string(state->getDepth() + 1, '>') << " " << x)
+#define NDN_LOG_TRACE_DEPTH(x) NDN_LOG_TRACE(std::string(state->getDepth() + 1, '>') << " " << x)
+
+CertificateBundleFetcher::CertificateBundleFetcher(unique_ptr<CertificateFetcher> inner,
+                                                   Face& face)
+  : m_inner(std::move(inner))
+  , m_face(face)
+  , m_bundleInterestLifetime(1000)
+{
+  BOOST_ASSERT(m_inner != nullptr);
+}
+
+void
+CertificateBundleFetcher::setBundleInterestLifetime(time::milliseconds time)
+{
+  m_bundleInterestLifetime = time;
+}
+
+time::milliseconds
+CertificateBundleFetcher::getBundleInterestLifetime() const
+{
+  return m_bundleInterestLifetime;
+}
+
+void
+CertificateBundleFetcher::setCertificateStorage(CertificateStorage& certStorage)
+{
+  m_certStorage = &certStorage;
+  m_inner->setCertificateStorage(certStorage);
+}
+
+void
+CertificateBundleFetcher::doFetch(const shared_ptr<CertificateRequest>& certRequest,
+                                  const shared_ptr<ValidationState>& state,
+                                  const ValidationContinuation& continueValidation)
+{
+  auto dataValidationState = dynamic_pointer_cast<DataValidationState>(state);
+  if (dataValidationState == nullptr) {
+    return m_inner->fetch(certRequest, state, continueValidation);
+  }
+
+  // check if a bundle segment was fetched before
+  shared_ptr<BundleNameTag> bundleNameTag = state->getTag<BundleNameTag>();
+  if (bundleNameTag == nullptr) {
+    const Name& originalDataName = dataValidationState->getOriginalData().getName();
+    if (originalDataName.empty()) {
+      return m_inner->fetch(certRequest, state, continueValidation);
+    }
+    // derive certificate bundle name from original data name
+    Name bundleNamePrefix = deriveBundleName(originalDataName);
+    fetchFirstBundleSegment(bundleNamePrefix, certRequest, state, continueValidation);
+  }
+  else {
+    Name fullBundleName = bundleNameTag->get();
+    fetchNextBundleSegment(fullBundleName, fullBundleName.get(-1).getSuccessor(),
+                           certRequest, state, continueValidation);
+  }
+}
+
+void
+CertificateBundleFetcher::fetchFirstBundleSegment(const Name& bundleNamePrefix,
+                                                  const shared_ptr<CertificateRequest>& certRequest,
+                                                  const shared_ptr<ValidationState>& state,
+                                                  const ValidationContinuation& continueValidation)
+{
+  Interest bundleInterest = Interest(bundleNamePrefix);
+  bundleInterest.setInterestLifetime(m_bundleInterestLifetime);
+  bundleInterest.setMustBeFresh(true);
+  bundleInterest.setChildSelector(1);
+
+  m_face.expressInterest(bundleInterest,
+                         [=] (const Interest& interest, const Data& data) {
+                           dataCallback(data, true, certRequest, state, continueValidation);
+                         },
+                         [=] (const Interest& interest, const lp::Nack& nack) {
+                           nackCallback(nack, certRequest, state, continueValidation, bundleNamePrefix);
+                         },
+                         [=] (const Interest& interest) {
+                           timeoutCallback(certRequest, state, continueValidation, bundleNamePrefix);
+                         });
+}
+
+void
+CertificateBundleFetcher::fetchNextBundleSegment(const Name& fullBundleName, const name::Component& segmentNo,
+                                                 const shared_ptr<CertificateRequest>& certRequest,
+                                                 const shared_ptr<ValidationState>& state,
+                                                 const ValidationContinuation& continueValidation)
+{
+  shared_ptr<FinalBlockIdTag> finalBlockId = state->getTag<FinalBlockIdTag>();
+  if (finalBlockId != nullptr && segmentNo > finalBlockId->get()) {
+    return m_inner->fetch(certRequest, state, continueValidation);
+  }
+
+  Interest bundleInterest(fullBundleName.getPrefix(-1).append(segmentNo));
+  bundleInterest.setInterestLifetime(m_bundleInterestLifetime);
+  bundleInterest.setMustBeFresh(false);
+
+  m_face.expressInterest(bundleInterest,
+                         [=] (const Interest& interest, const Data& data) {
+                           dataCallback(data, false, certRequest, state, continueValidation);
+                         },
+                         [=] (const Interest& interest, const lp::Nack& nack) {
+                           nackCallback(nack, certRequest, state, continueValidation, fullBundleName);
+                         },
+                         [=] (const Interest& interest) {
+                           timeoutCallback(certRequest, state, continueValidation, fullBundleName);
+                         });
+}
+
+void
+CertificateBundleFetcher::dataCallback(const Data& bundleData,
+                                       bool isSegmentZeroExpected,
+                                       const shared_ptr<CertificateRequest>& certRequest,
+                                       const shared_ptr<ValidationState>& state,
+                                       const ValidationContinuation& continueValidation)
+{
+  NDN_LOG_DEBUG_DEPTH("Fetched certificate bundle from network " << bundleData.getName());
+
+  name::Component currentSegment = bundleData.getName().get(-1);
+  if (!currentSegment.isSegment()) {
+    return m_inner->fetch(certRequest, state, continueValidation);
+  }
+
+  if (isSegmentZeroExpected && currentSegment.toSegment() != 0) {
+    // fetch segment zero
+    fetchNextBundleSegment(bundleData.getName(), name::Component::fromSegment(0),
+                           certRequest, state, continueValidation);
+  }
+  else {
+    state->setTag(make_shared<BundleNameTag>(bundleData.getName()));
+
+    const name::Component& finalBlockId = bundleData.getMetaInfo().getFinalBlockId();
+    if (!finalBlockId.empty()) {
+      state->setTag(make_shared<FinalBlockIdTag>(finalBlockId));
+    }
+
+    Block bundleContent = bundleData.getContent();
+    bundleContent.parse();
+
+    // store all the certificates in unverified cache
+    for (const auto& block : bundleContent.elements()) {
+      m_certStorage->cacheUnverifiedCert(Certificate(block));
+    }
+
+    auto cert = m_certStorage->getUnverifiedCertCache().find(certRequest->m_interest);
+    continueValidation(*cert, state);
+  }
+}
+
+void
+CertificateBundleFetcher::nackCallback(const lp::Nack& nack,
+                                       const shared_ptr<CertificateRequest>& certRequest,
+                                       const shared_ptr<ValidationState>& state,
+                                       const ValidationContinuation& continueValidation,
+                                       const Name& bundleName)
+{
+  NDN_LOG_DEBUG_DEPTH("NACK (" << nack.getReason() <<  ") while fetching certificate bundle"
+                      << bundleName);
+
+  m_inner->fetch(certRequest, state, continueValidation);
+}
+
+void
+CertificateBundleFetcher::timeoutCallback(const shared_ptr<CertificateRequest>& certRequest,
+                                          const shared_ptr<ValidationState>& state,
+                                          const ValidationContinuation& continueValidation,
+                                          const Name& bundleName)
+{
+  NDN_LOG_DEBUG_DEPTH("Timeout while fetching certificate bundle" << bundleName);
+
+  m_inner->fetch(certRequest, state, continueValidation);
+}
+
+Name
+CertificateBundleFetcher::deriveBundleName(const Name& name)
+{
+  name::Component lastComponent = name.at(-1);
+
+  Name bundleName = name;
+  if (lastComponent.isImplicitSha256Digest()) {
+    if (name.size() >= 2 && name.get(-2).isSegment()) {
+      bundleName = name.getPrefix(-2);
+    }
+    else {
+      bundleName = name.getPrefix(-1);
+    }
+  }
+  else if (lastComponent.isSegment()) {
+    bundleName = name.getPrefix(-1);
+  }
+  bundleName.append("_BUNDLE");
+  bundleName.appendNumber(00);
+
+  return bundleName;
+}
+
+} // namespace v2
+} // namespace security
+} // namespace ndn
diff --git a/src/security/v2/certificate-bundle-fetcher.hpp b/src/security/v2/certificate-bundle-fetcher.hpp
new file mode 100644
index 0000000..bcd2f36
--- /dev/null
+++ b/src/security/v2/certificate-bundle-fetcher.hpp
@@ -0,0 +1,149 @@
+/* -*- 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_SECURITY_V2_CERTIFICATE_BUNDLE_FETCHER_HPP
+#define NDN_SECURITY_V2_CERTIFICATE_BUNDLE_FETCHER_HPP
+
+#include "certificate-fetcher-from-network.hpp"
+
+namespace ndn {
+namespace security {
+namespace v2 {
+
+/**
+ * @brief Fetch certificate bundle from the network
+ *
+ * Currently bundle fetching is attempted only for Data validation. This may change in the
+ * future. Bundle fetching always goes to the infrastructure regardless of the inner
+ * fetcher. Inner fetcher is used when the bundle interest times out or returns a Nack or when
+ * additional certificates are needed for validation.
+ *
+ * @sa https://redmine.named-data.net/projects/ndn-cxx/wiki/Certificate_Bundle_Packet_Format
+ */
+class CertificateBundleFetcher : public CertificateFetcher
+{
+public:
+  explicit
+  CertificateBundleFetcher(unique_ptr<CertificateFetcher> inner,
+                           Face& face);
+
+  /**
+   * @brief Set the lifetime of certificate bundle interest
+   */
+  void
+  setBundleInterestLifetime(time::milliseconds time);
+
+  /**
+   * @return The lifetime of certificate bundle interest
+   */
+  time::milliseconds
+  getBundleInterestLifetime() const;
+
+  /**
+   * Set the storage for this and inner certificate fetcher
+   */
+  void
+  setCertificateStorage(CertificateStorage& certStorage) override;
+
+protected:
+  void
+  doFetch(const shared_ptr<CertificateRequest>& certRequest, const shared_ptr<ValidationState>& state,
+          const ValidationContinuation& continueValidation) override;
+
+private:
+  /**
+   * @brief Fetch the first bundle segment.
+   *
+   * After deriving the bundle name prefix, the exact version of the bundle is not yet known.
+   * This method express Interest for the bundle prefix to (1) retrieve first segment of the bundle and
+   * (2) discover bundle version. The bundle version will be recorded in the validation state as BundleNameTag
+   * and will be used in subsequent @p fetchNextBundleSegment calls to fetch further bundle segments if needed.
+   */
+  void
+  fetchFirstBundleSegment(const Name& bundleNamePrefix,
+                          const shared_ptr<CertificateRequest>& certRequest,
+                          const shared_ptr<ValidationState>& state,
+                          const ValidationContinuation& continueValidation);
+
+  /**
+   * @brief Fetch the specified bundle segment.
+   */
+  void
+  fetchNextBundleSegment(const Name& fullBundleName, const name::Component& segmentNo,
+                         const shared_ptr<CertificateRequest>& certRequest,
+                         const shared_ptr<ValidationState>& state,
+                         const ValidationContinuation& continueValidation);
+
+  /**
+   * @brief Derive bundle name from data name.
+   *
+   * Current naming conventions are as follows:
+   * /<derived(data_name)>/BUNDLE/<trust-model>/<version>/<seg>
+   *
+   * Current rules for derived(data_name):
+   * (1) If the last component is Implicit Digest AND the second last component is Segment number
+   * then derived(data_name) = data_name.getPrefix(-2)
+   * (2) If the last component is Implicit Digest
+   * then derived(data_name) = data_name.getPrefix(-1)
+   * (3) If the last component is Segment number
+   * then derived(data_name) = data_name.getPrefix(-1)
+   *
+   * <trust-model> component is "00" for single hierarchy trust models.
+   */
+  static Name
+  deriveBundleName(const Name& name);
+
+  /**
+   * @brief Callback invoked when certificate bundle is retrieved.
+   */
+  void
+  dataCallback(const Data& data, bool isSegmentZeroExpected,
+               const shared_ptr<CertificateRequest>& certRequest, const shared_ptr<ValidationState>& state,
+               const ValidationContinuation& continueValidation);
+
+  /**
+   * @brief Callback invoked when interest for fetching certificate bundle gets NACKed.
+   */
+  void
+  nackCallback(const lp::Nack& nack,
+               const shared_ptr<CertificateRequest>& certRequest, const shared_ptr<ValidationState>& state,
+               const ValidationContinuation& continueValidation, const Name& bundleName);
+
+  /**
+   * @brief Callback invoked when interest for fetching certificate times out.
+   */
+  void
+  timeoutCallback(const shared_ptr<CertificateRequest>& certRequest, const shared_ptr<ValidationState>& state,
+                  const ValidationContinuation& continueValidation, const Name& bundleName);
+
+private:
+  unique_ptr<CertificateFetcher> m_inner;
+  Face& m_face;
+  using BundleNameTag = SimpleTag<Name, 1000>;
+  using FinalBlockIdTag = SimpleTag<name::Component, 1001>;
+  time::milliseconds m_bundleInterestLifetime;
+};
+
+} // namespace v2
+} // namespace security
+} // namespace ndn
+
+#endif // NDN_SECURITY_V2_CERTIFICATE_BUNDLE_FETCHER_HPP
diff --git a/src/security/v2/certificate-fetcher.hpp b/src/security/v2/certificate-fetcher.hpp
index 7abc5f5..cbf221b 100644
--- a/src/security/v2/certificate-fetcher.hpp
+++ b/src/security/v2/certificate-fetcher.hpp
@@ -51,7 +51,7 @@
    * @brief Assign certificate storage to check known certificate and to cache unverified ones
    * @note The supplied @p certStorage should be valid for the lifetime of CertificateFetcher
    */
-  void
+  virtual void
   setCertificateStorage(CertificateStorage& certStorage);
 
   /**
diff --git a/tests/unit-tests/security/v2/certificate-bundle-fetcher.t.cpp b/tests/unit-tests/security/v2/certificate-bundle-fetcher.t.cpp
new file mode 100644
index 0000000..b837339
--- /dev/null
+++ b/tests/unit-tests/security/v2/certificate-bundle-fetcher.t.cpp
@@ -0,0 +1,191 @@
+/* -*- 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.
+ */
+
+#include "security/v2/certificate-bundle-fetcher.hpp"
+#include "security/v2/validation-policy-simple-hierarchy.hpp"
+#include "util/regex/regex-pattern-list-matcher.hpp"
+#include "lp/nack.hpp"
+
+#include "boost-test.hpp"
+#include "validator-fixture.hpp"
+
+namespace ndn {
+namespace security {
+namespace v2 {
+namespace tests {
+
+using namespace ndn::tests;
+
+BOOST_AUTO_TEST_SUITE(Security)
+BOOST_AUTO_TEST_SUITE(V2)
+BOOST_AUTO_TEST_SUITE(TestCertificateBundleFetcher)
+
+class CertificateBundleFetcherWrapper : public CertificateBundleFetcher
+{
+public:
+  CertificateBundleFetcherWrapper(Face& face)
+    : CertificateBundleFetcher(make_unique<CertificateFetcherFromNetwork>(face), face)
+  {
+  }
+};
+
+class Bundle
+{
+};
+
+class Cert
+{
+};
+
+class Timeout
+{
+};
+
+class Nack
+{
+};
+
+template<class Response>
+class CertificateBundleFetcherFixture : public HierarchicalValidatorFixture<ValidationPolicySimpleHierarchy,
+                                                                            CertificateBundleFetcherWrapper>
+{
+public:
+  CertificateBundleFetcherFixture()
+    : data("/Security/V2/ValidatorFixture/Sub1/Sub3/Data")
+  {
+    subSubIdentity = addSubCertificate("/Security/V2/ValidatorFixture/Sub1/Sub3", subIdentity);
+    cache.insert(subSubIdentity.getDefaultKey().getDefaultCertificate());
+
+    m_keyChain.sign(data, signingByIdentity(subSubIdentity));
+    bundleRegexMatcher = make_shared<RegexPatternListMatcher>("<>*<_BUNDLE><>*", nullptr);
+    processInterest = [this] (const Interest& interest) {
+      // check if the interest is for Bundle or individual certificates
+      if (bundleRegexMatcher->match(interest.getName(), 0, interest.getName().size())) {
+        makeResponse(interest);
+      }
+      else {
+        auto cert = cache.find(interest);
+        if (cert == nullptr) {
+          return;
+        }
+        face.receive(*cert);
+      }
+    };
+  }
+
+  void
+  makeResponse(const Interest& interest);
+
+public:
+  Data data;
+  Identity subSubIdentity;
+  shared_ptr<RegexPatternListMatcher> bundleRegexMatcher;
+};
+
+template<>
+void
+CertificateBundleFetcherFixture<Bundle>::makeResponse(const Interest& interest)
+{
+  Block certList = Block(tlv::Content);
+  Name bundleName(interest.getName());
+
+  if (!bundleName.get(-1).isSegment() || bundleName.get(-1).toSegment() == 0) {
+    Block subSubCert = subSubIdentity.getDefaultKey().getDefaultCertificate().wireEncode();
+    certList.push_back(subSubCert);
+
+    if (!bundleName.get(-1).isSegment()) {
+      bundleName
+        .appendVersion()
+        .appendSegment(0);
+    }
+  }
+  else {
+    Block subCert = subIdentity.getDefaultKey().getDefaultCertificate().wireEncode();
+    Block anchor = identity.getDefaultKey().getDefaultCertificate().wireEncode();
+    certList.push_back(subCert);
+    certList.push_back(anchor);
+  }
+
+  shared_ptr<Data> certBundle = make_shared<Data>();
+  certBundle->setName(bundleName);
+  certBundle->setFreshnessPeriod(time::seconds(100));
+  certBundle->setContent(certList);
+  certBundle->setFinalBlockId(name::Component::fromSegment(1));
+
+  m_keyChain.sign(*certBundle, signingWithSha256());
+
+  face.receive(*certBundle);
+}
+
+template<>
+void
+CertificateBundleFetcherFixture<Timeout>::makeResponse(const Interest& interest)
+{
+  this->advanceClocks(time::seconds(200));
+}
+
+template<>
+void
+CertificateBundleFetcherFixture<Nack>::makeResponse(const Interest& interest)
+{
+  lp::Nack nack(interest);
+  nack.setHeader(lp::NackHeader().setReason(lp::NackReason::NO_ROUTE));
+  face.receive(nack);
+}
+
+BOOST_FIXTURE_TEST_CASE(ValidateSuccessWithBundle, CertificateBundleFetcherFixture<Bundle>)
+{
+  VALIDATE_SUCCESS(this->data, "Should get accepted, as interest brings the bundle segments");
+  BOOST_CHECK_EQUAL(this->face.sentInterests.size(), 2); // produced bundle has 2 segments
+
+  for (const auto& sentInterest : this->face.sentInterests) {
+    BOOST_CHECK(this->bundleRegexMatcher->match(sentInterest.getName(), 0, sentInterest.getName().size()));
+  }
+}
+
+using SuccessWithoutBundle = boost::mpl::vector<Nack, Timeout>;
+
+BOOST_FIXTURE_TEST_CASE_TEMPLATE(ValidateSuccessWithoutBundle, T, SuccessWithoutBundle, CertificateBundleFetcherFixture<T>)
+{
+  VALIDATE_SUCCESS(this->data, "Should get accepted, as interest brings the certs");
+  BOOST_CHECK_EQUAL(this->face.sentInterests.size(), 4); // since interest for Bundle fails, each cert is retrieved
+
+  bool toggle = true;
+  for (const auto& sentInterest : this->face.sentInterests) {
+    if (toggle) {
+      // every alternate interest is going to be that of a bundle
+      BOOST_CHECK(this->bundleRegexMatcher->match(sentInterest.getName(), 0, sentInterest.getName().size()));
+    }
+    else {
+      BOOST_CHECK(!this->bundleRegexMatcher->match(sentInterest.getName(), 0, sentInterest.getName().size()));
+    }
+    toggle = !toggle;
+  }
+}
+
+BOOST_AUTO_TEST_SUITE_END() // TestCertificateBundleFetcher
+BOOST_AUTO_TEST_SUITE_END() // V2
+BOOST_AUTO_TEST_SUITE_END() // Security
+
+} // namespace tests
+} // namespace v2
+} // namespace security
+} // namespace ndn