readvertise.cpp
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1 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
2 /*
3  * Copyright (c) 2014-2022, Regents of the University of California,
4  * Arizona Board of Regents,
5  * Colorado State University,
6  * University Pierre & Marie Curie, Sorbonne University,
7  * Washington University in St. Louis,
8  * Beijing Institute of Technology,
9  * The University of Memphis.
10  *
11  * This file is part of NFD (Named Data Networking Forwarding Daemon).
12  * See AUTHORS.md for complete list of NFD authors and contributors.
13  *
14  * NFD is free software: you can redistribute it and/or modify it under the terms
15  * of the GNU General Public License as published by the Free Software Foundation,
16  * either version 3 of the License, or (at your option) any later version.
17  *
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20  * PURPOSE. See the GNU General Public License for more details.
21  *
22  * You should have received a copy of the GNU General Public License along with
23  * NFD, e.g., in COPYING.md file. If not, see <http://www.gnu.org/licenses/>.
24  */
25 
26 #include "readvertise.hpp"
27 #include "common/global.hpp"
28 #include "common/logger.hpp"
29 
30 #include <ndn-cxx/util/random.hpp>
31 
32 namespace nfd::rib {
33 
34 NFD_LOG_INIT(Readvertise);
35 
36 constexpr time::milliseconds RETRY_DELAY_MIN = 50_s;
37 constexpr time::milliseconds RETRY_DELAY_MAX = 1_h;
38 
39 static time::milliseconds
40 randomizeTimer(time::milliseconds baseTimer)
41 {
42  std::uniform_int_distribution<> dist(-5, 5);
43  auto newTime = baseTimer + time::milliseconds(dist(ndn::random::getRandomNumberEngine()));
44  return std::max(newTime, 0_ms);
45 }
46 
48  unique_ptr<ReadvertisePolicy> policy,
49  unique_ptr<ReadvertiseDestination> destination)
50  : m_policy(std::move(policy))
51  , m_destination(std::move(destination))
52 {
53  m_addRouteConn = rib.afterAddRoute.connect([this] (const auto& r) { this->afterAddRoute(r); });
54  m_removeRouteConn = rib.beforeRemoveRoute.connect([this] (const auto& r) { this->beforeRemoveRoute(r); });
55 
56  m_destination->afterAvailabilityChange.connect([this] (bool isAvailable) {
57  if (isAvailable) {
58  this->afterDestinationAvailable();
59  }
60  else {
61  this->afterDestinationUnavailable();
62  }
63  });
64 }
65 
66 void
67 Readvertise::afterAddRoute(const RibRouteRef& ribRoute)
68 {
69  std::optional<ReadvertiseAction> action = m_policy->handleNewRoute(ribRoute);
70  if (!action) {
71  NFD_LOG_DEBUG("add-route " << ribRoute.entry->getName() << '(' << ribRoute.route->faceId <<
72  ',' << ribRoute.route->origin << ") not-readvertising");
73  return;
74  }
75 
76  auto [rrIt, isNewRr] = m_rrs.emplace(action->prefix);
77  if (!isNewRr && rrIt->signer != action->signer) {
78  NFD_LOG_WARN("add-route " << ribRoute.entry->getName() << '(' << ribRoute.route->faceId <<
79  ',' << ribRoute.route->origin << ") readvertising-as " << action->prefix <<
80  " old-signer " << rrIt->signer << " new-signer " << action->signer);
81  }
82  rrIt->signer = action->signer;
83 
84  bool isNewInMap = m_routeToRr.try_emplace(ribRoute, rrIt).second;
85  BOOST_VERIFY(isNewInMap);
86 
87  if (rrIt->nRibRoutes++ > 0) {
88  NFD_LOG_DEBUG("add-route " << ribRoute.entry->getName() << '(' << ribRoute.route->faceId <<
89  ',' << ribRoute.route->origin << ") already-readvertised-as " << action->prefix);
90  return;
91  }
92 
93  NFD_LOG_DEBUG("add-route " << ribRoute.entry->getName() << '(' << ribRoute.route->faceId <<
94  ',' << ribRoute.route->origin << ") readvertising-as " << action->prefix <<
95  " signer " << action->signer);
96  rrIt->retryDelay = RETRY_DELAY_MIN;
97  this->advertise(rrIt);
98 }
99 
100 void
101 Readvertise::beforeRemoveRoute(const RibRouteRef& ribRoute)
102 {
103  auto indexIt = m_routeToRr.find(ribRoute);
104  if (indexIt == m_routeToRr.end()) {
105  NFD_LOG_DEBUG("remove-route " << ribRoute.entry->getName() << '(' << ribRoute.route->faceId <<
106  ',' << ribRoute.route->origin << ") not-readvertised");
107  return;
108  }
109 
110  auto rrIt = indexIt->second;
111  m_routeToRr.erase(indexIt);
112 
113  if (--rrIt->nRibRoutes > 0) {
114  NFD_LOG_DEBUG("remove-route " << ribRoute.entry->getName() << '(' << ribRoute.route->faceId <<
115  ',' << ribRoute.route->origin << ") needed-by " << rrIt->nRibRoutes);
116  return;
117  }
118 
119  rrIt->retryDelay = RETRY_DELAY_MIN;
120  this->withdraw(rrIt);
121 }
122 
123 void
124 Readvertise::afterDestinationAvailable()
125 {
126  for (auto rrIt = m_rrs.begin(); rrIt != m_rrs.end(); ++rrIt) {
127  rrIt->retryDelay = RETRY_DELAY_MIN;
128  this->advertise(rrIt);
129  }
130 }
131 
132 void
133 Readvertise::afterDestinationUnavailable()
134 {
135  for (auto rrIt = m_rrs.begin(); rrIt != m_rrs.end();) {
136  if (rrIt->nRibRoutes > 0) {
137  rrIt->retryEvt.cancel(); // stop retrying or refreshing
138  ++rrIt;
139  }
140  else {
141  rrIt = m_rrs.erase(rrIt); // assume withdraw has completed
142  }
143  }
144 }
145 
146 void
147 Readvertise::advertise(ReadvertisedRouteContainer::iterator rrIt)
148 {
149  BOOST_ASSERT(rrIt->nRibRoutes > 0);
150 
151  if (!m_destination->isAvailable()) {
152  NFD_LOG_DEBUG("advertise " << rrIt->prefix << " destination-unavailable");
153  return;
154  }
155 
156  m_destination->advertise(*rrIt,
157  [=] {
158  NFD_LOG_DEBUG("advertise " << rrIt->prefix << " success");
159  rrIt->retryDelay = RETRY_DELAY_MIN;
160  rrIt->retryEvt = getScheduler().schedule(randomizeTimer(m_policy->getRefreshInterval()),
161  [=] { advertise(rrIt); });
162  },
163  [=] (const std::string& msg) {
164  NFD_LOG_DEBUG("advertise " << rrIt->prefix << " failure " << msg);
165  rrIt->retryDelay = std::min(RETRY_DELAY_MAX, rrIt->retryDelay * 2);
166  rrIt->retryEvt = getScheduler().schedule(randomizeTimer(rrIt->retryDelay),
167  [=] { advertise(rrIt); });
168  });
169 }
170 
171 void
172 Readvertise::withdraw(ReadvertisedRouteContainer::iterator rrIt)
173 {
174  BOOST_ASSERT(rrIt->nRibRoutes == 0);
175 
176  if (!m_destination->isAvailable()) {
177  NFD_LOG_DEBUG("withdraw " << rrIt->prefix << " destination-unavailable");
178  m_rrs.erase(rrIt);
179  return;
180  }
181 
182  m_destination->withdraw(*rrIt,
183  [=] {
184  NFD_LOG_DEBUG("withdraw " << rrIt->prefix << " success");
185  m_rrs.erase(rrIt);
186  },
187  [=] (const std::string& msg) {
188  NFD_LOG_DEBUG("withdraw " << rrIt->prefix << " failure " << msg);
189  rrIt->retryDelay = std::min(RETRY_DELAY_MAX, rrIt->retryDelay * 2);
190  rrIt->retryEvt = getScheduler().schedule(randomizeTimer(rrIt->retryDelay),
191  [=] { withdraw(rrIt); });
192  });
193 }
194 
195 } // namespace nfd::rib
Readvertise(Rib &rib, unique_ptr< ReadvertisePolicy > policy, unique_ptr< ReadvertiseDestination > destination)
Definition: readvertise.cpp:47
Represents the Routing Information Base.
Definition: rib.hpp:70
signal::Signal< Rib, RibRouteRef > afterAddRoute
Signals after a Route is added.
Definition: rib.hpp:235
signal::Signal< Rib, RibRouteRef > beforeRemoveRoute
Signals before a route is removed.
Definition: rib.hpp:239
#define NFD_LOG_INIT(name)
Definition: logger.hpp:31
#define NFD_LOG_WARN
Definition: logger.hpp:40
#define NFD_LOG_DEBUG
Definition: logger.hpp:38
constexpr time::milliseconds RETRY_DELAY_MAX
Definition: readvertise.cpp:37
static time::milliseconds randomizeTimer(time::milliseconds baseTimer)
Definition: readvertise.cpp:40
constexpr time::milliseconds RETRY_DELAY_MIN
Definition: readvertise.cpp:36
ndn::Scheduler & getScheduler()
Returns the global Scheduler instance for the calling thread.
Definition: global.cpp:45
References a route.
Definition: rib.hpp:47
shared_ptr< RibEntry > entry
Definition: rib.hpp:48
RibEntry::const_iterator route
Definition: rib.hpp:49