Kea  2.1.7-git
cb_ctl_dhcp4.cc
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1 // Copyright (C) 2019-2022 Internet Systems Consortium, Inc. ("ISC")
2 //
3 // This Source Code Form is subject to the terms of the Mozilla Public
4 // License, v. 2.0. If a copy of the MPL was not distributed with this
5 // file, You can obtain one at http://mozilla.org/MPL/2.0/.
6 
7 #include <config.h>
8 #include <dhcpsrv/cb_ctl_dhcp4.h>
9 #include <dhcpsrv/cfgmgr.h>
11 #include <dhcpsrv/dhcpsrv_log.h>
12 #include <dhcpsrv/host_mgr.h>
14 #include <hooks/callout_handle.h>
15 #include <hooks/hooks_manager.h>
16 
17 using namespace isc::db;
18 using namespace isc::data;
19 using namespace isc::process;
20 using namespace isc::hooks;
21 
22 namespace {
23 
25 struct CbCtlHooks {
26  int hook_index_cb4_updated_;
27 
29  CbCtlHooks() {
30  hook_index_cb4_updated_ = HooksManager::registerHook("cb4_updated");
31  }
32 };
33 
34 // Declare a Hooks object. As this is outside any function or method, it
35 // will be instantiated (and the constructor run) when the module is loaded.
36 // As a result, the hook indexes will be defined before any method in this
37 // module is called.
38 CbCtlHooks hooks_;
39 
40 }; // anonymous namespace
41 
42 namespace isc {
43 namespace dhcp {
44 
45 void
46 CBControlDHCPv4::databaseConfigApply(const BackendSelector& backend_selector,
47  const ServerSelector& server_selector,
48  const boost::posix_time::ptime& lb_modification_time,
49  const AuditEntryCollection& audit_entries) {
50 
51  bool globals_fetched = false;
52 
53  // Let's first delete all the configuration elements for which DELETE audit
54  // entries are found. Although, this may break chronology of the audit in
55  // some cases it should not affect the end result of the data fetch. If the
56  // object was created and then subsequently deleted, we will first try to
57  // delete this object from the local configuration (which will fail because
58  // the object does not exist) and then we will try to fetch it from the
59  // database which will return no result.
60  if (!audit_entries.empty()) {
61 
62  auto cfg = CfgMgr::instance().getCurrentCfg();
63  auto external_cfg = CfgMgr::instance().createExternalCfg();
64 
65  // Get audit entries for deleted global parameters.
66  const auto& index = audit_entries.get<AuditEntryObjectTypeTag>();
67  auto range = index.equal_range(boost::make_tuple("dhcp4_global_parameter",
69  if (range.first != range.second) {
70  // Some globals have been deleted. Since we currently don't track database
71  // identifiers of the global parameters we have to fetch all global
72  // parameters for this server. Next, we simply replace existing
73  // global parameters with the new parameters. This is slightly
74  // inefficient but only slightly. Note that this is a single
75  // database query and the number of global parameters is small.
77  globals = getMgr().getPool()->getAllGlobalParameters4(backend_selector, server_selector);
78  addGlobalsToConfig(external_cfg, globals);
79 
80  // Add defaults.
81  external_cfg->applyDefaultsConfiguredGlobals(SimpleParser4::GLOBAL4_DEFAULTS);
82 
83  // Sanity check it.
84  external_cfg->sanityChecksLifetime("valid-lifetime");
85 
86  // Now that we successfully fetched the new global parameters, let's
87  // remove existing ones and merge them into the current configuration.
88  cfg->clearConfiguredGlobals();
89  CfgMgr::instance().mergeIntoCurrentCfg(external_cfg->getSequence());
90  globals_fetched = true;
91  }
92 
93  try {
94  // Get audit entries for deleted option definitions and delete each
95  // option definition from the current configuration for which the
96  // audit entry is found.
97  range = index.equal_range(boost::make_tuple("dhcp4_option_def",
99  for (auto entry = range.first; entry != range.second; ++entry) {
100  cfg->getCfgOptionDef()->del((*entry)->getObjectId());
101  }
102 
103  // Repeat the same for other configuration elements.
104 
105  range = index.equal_range(boost::make_tuple("dhcp4_options",
107  for (auto entry = range.first; entry != range.second; ++entry) {
108  cfg->getCfgOption()->del((*entry)->getObjectId());
109  }
110 
111  range = index.equal_range(boost::make_tuple("dhcp4_client_class",
113  for (auto entry = range.first; entry != range.second; ++entry) {
114  cfg->getClientClassDictionary()->removeClass((*entry)->getObjectId());
115  }
116 
117  range = index.equal_range(boost::make_tuple("dhcp4_shared_network",
119  for (auto entry = range.first; entry != range.second; ++entry) {
120  cfg->getCfgSharedNetworks4()->del((*entry)->getObjectId());
121  }
122 
123  range = index.equal_range(boost::make_tuple("dhcp4_subnet",
125  for (auto entry = range.first; entry != range.second; ++entry) {
126  // If the deleted subnet belongs to a shared network and the
127  // shared network is not being removed, we need to detach the
128  // subnet from the shared network.
129  auto subnet = cfg->getCfgSubnets4()->getBySubnetId((*entry)->getObjectId());
130  if (subnet) {
131  // Check if the subnet belongs to a shared network.
132  SharedNetwork4Ptr network;
133  subnet->getSharedNetwork(network);
134  if (network) {
135  // Detach the subnet from the shared network.
136  network->del(subnet->getID());
137  }
138  // Actually delete the subnet from the configuration.
139  cfg->getCfgSubnets4()->del((*entry)->getObjectId());
140  }
141  }
142 
143  } catch (...) {
144  // Ignore errors thrown when attempting to delete a non-existing
145  // configuration entry. There is no guarantee that the deleted
146  // entry is actually there as we're not processing the audit
147  // chronologically.
148  }
149  }
150 
151  // Create the external config into which we'll fetch backend config data.
152  SrvConfigPtr external_cfg = CfgMgr::instance().createExternalCfg();
153 
154  // First let's fetch the globals and add them to external config.
155  AuditEntryCollection updated_entries;
156  if (!globals_fetched && !audit_entries.empty()) {
157  updated_entries = fetchConfigElement(audit_entries, "dhcp4_global_parameter");
158  }
159  if (!globals_fetched && (audit_entries.empty() || !updated_entries.empty())) {
161  globals = getMgr().getPool()->getModifiedGlobalParameters4(backend_selector, server_selector,
162  lb_modification_time);
163  addGlobalsToConfig(external_cfg, globals);
164  globals_fetched = true;
165  }
166 
167  // Now we fetch the option definitions and add them.
168  if (!audit_entries.empty()) {
169  updated_entries = fetchConfigElement(audit_entries, "dhcp4_option_def");
170  }
171  if (audit_entries.empty() || !updated_entries.empty()) {
172  OptionDefContainer option_defs =
173  getMgr().getPool()->getModifiedOptionDefs4(backend_selector, server_selector,
174  lb_modification_time);
175  for (auto option_def = option_defs.begin(); option_def != option_defs.end(); ++option_def) {
176  if (!audit_entries.empty() && !hasObjectId(updated_entries, (*option_def)->getId())) {
177  continue;
178  }
179  external_cfg->getCfgOptionDef()->add(*option_def);
180  }
181  }
182 
183  // Next fetch the options. They are returned as a container of OptionDescriptors.
184  if (!audit_entries.empty()) {
185  updated_entries = fetchConfigElement(audit_entries, "dhcp4_options");
186  }
187  if (audit_entries.empty() || !updated_entries.empty()) {
188  OptionContainer options = getMgr().getPool()->getModifiedOptions4(backend_selector,
189  server_selector,
190  lb_modification_time);
191  for (auto option = options.begin(); option != options.end(); ++option) {
192  if (!audit_entries.empty() && !hasObjectId(updated_entries, (*option).getId())) {
193  continue;
194  }
195  external_cfg->getCfgOption()->add((*option), (*option).space_name_);
196  }
197  }
198 
199  // Fetch client classes. They are returned in a ClientClassDictionary.
200  if (!audit_entries.empty()) {
201  updated_entries = fetchConfigElement(audit_entries, "dhcp4_client_class");
202  }
203  if (audit_entries.empty() || !updated_entries.empty()) {
204  ClientClassDictionary client_classes = getMgr().getPool()->getAllClientClasses4(backend_selector,
205  server_selector);
206  // Match expressions are not initialized for classes returned from the config backend.
207  // We have to ensure to initialize them before they can be used by the server.
208  client_classes.initMatchExpr(AF_INET);
209 
210  // Class options also need to be created when returned from the config backend.
211  client_classes.createOptions(external_cfg->getCfgOptionDef());
212 
213  external_cfg->setClientClassDictionary(boost::make_shared<ClientClassDictionary>(client_classes));
214  }
215 
216  // Now fetch the shared networks.
217  if (!audit_entries.empty()) {
218  updated_entries = fetchConfigElement(audit_entries, "dhcp4_shared_network");
219  }
220  if (audit_entries.empty() || !updated_entries.empty()) {
221  SharedNetwork4Collection networks =
222  getMgr().getPool()->getModifiedSharedNetworks4(backend_selector, server_selector,
223  lb_modification_time);
224  for (auto network = networks.begin(); network != networks.end(); ++network) {
225  if (!audit_entries.empty() && !hasObjectId(updated_entries, (*network)->getId())) {
226  continue;
227  }
228  // In order to take advantage of the dynamic inheritance of global
229  // parameters to a shared network we need to set a callback function
230  // for each network to allow for fetching global parameters.
231  (*network)->setFetchGlobalsFn([] () -> ConstCfgGlobalsPtr {
232  return (CfgMgr::instance().getCurrentCfg()->getConfiguredGlobals());
233  });
234  external_cfg->getCfgSharedNetworks4()->add((*network));
235  }
236  }
237 
238  // Next we fetch subnets.
239  if (!audit_entries.empty()) {
240  updated_entries = fetchConfigElement(audit_entries, "dhcp4_subnet");
241  }
242  if (audit_entries.empty() || !updated_entries.empty()) {
243  Subnet4Collection subnets = getMgr().getPool()->getModifiedSubnets4(backend_selector,
244  server_selector,
245  lb_modification_time);
246  for (auto subnet = subnets.begin(); subnet != subnets.end(); ++subnet) {
247  if (!audit_entries.empty() && !hasObjectId(updated_entries, (*subnet)->getID())) {
248  continue;
249  }
250  // In order to take advantage of the dynamic inheritance of global
251  // parameters to a subnet we need to set a callback function for each
252  // subnet to allow for fetching global parameters.
253  (*subnet)->setFetchGlobalsFn([] () -> ConstCfgGlobalsPtr {
254  return (CfgMgr::instance().getCurrentCfg()->getConfiguredGlobals());
255  });
256  external_cfg->getCfgSubnets4()->add((*subnet));
257  }
258  }
259 
260  if (audit_entries.empty()) {
261  // If we're configuring the server after startup, we do not apply the
262  // ip-reservations-unique setting here. It will be applied when the
263  // configuration is committed.
264  auto const& cfg = CfgMgr::instance().getStagingCfg();
265  external_cfg->sanityChecksLifetime(*cfg, "valid-lifetime");
266  CfgMgr::instance().mergeIntoStagingCfg(external_cfg->getSequence());
267  } else {
268  if (globals_fetched) {
269  // ip-reservations-unique parameter requires special handling because
270  // setting it to false may be unsupported by some host backends.
271  bool ip_unique = true;
272  auto ip_unique_param = external_cfg->getConfiguredGlobal("ip-reservations-unique");
273  if (ip_unique_param && (ip_unique_param->getType() == Element::boolean)) {
274  ip_unique = ip_unique_param->boolValue();
275  }
276  // First try to use the new setting to configure the HostMgr because it
277  // may fail if the backend does not support it.
278  if (!HostMgr::instance().setIPReservationsUnique(ip_unique)) {
279  // The new setting is unsupported by the backend, so do not apply this
280  // setting at all.
282  external_cfg->addConfiguredGlobal("ip-reservations-unique", Element::create(true));
283  }
284  }
285  auto const& cfg = CfgMgr::instance().getCurrentCfg();
286  external_cfg->sanityChecksLifetime(*cfg, "valid-lifetime");
287  CfgMgr::instance().mergeIntoCurrentCfg(external_cfg->getSequence());
288  }
290 
291  if (!audit_entries.empty() &&
292  HooksManager::calloutsPresent(hooks_.hook_index_cb4_updated_)) {
293  CalloutHandlePtr callout_handle = HooksManager::createCalloutHandle();
294 
295  // Use the RAII wrapper to make sure that the callout handle state is
296  // reset when this object goes out of scope. All hook points must do
297  // it to prevent possible circular dependency between the callout
298  // handle and its arguments.
299  ScopedCalloutHandleState callout_handle_state(callout_handle);
300 
301  // Pass a shared pointer to audit entries.
302  AuditEntryCollectionPtr ptr(new AuditEntryCollection(audit_entries));
303  callout_handle->setArgument("audit_entries", ptr);
304 
305  // Call the callouts
306  HooksManager::callCallouts(hooks_.hook_index_cb4_updated_, *callout_handle);
307 
308  // Ignore the result.
309  }
310 }
311 
312 } // end of namespace isc::dhcp
313 } // end of namespace isc
const isc::log::MessageID DHCPSRV_CFGMGR_CONFIG4_MERGED
#define LOG_WARN(LOGGER, MESSAGE)
Macro to conveniently test warn output and log it.
Definition: macros.h:26
#define LOG_INFO(LOGGER, MESSAGE)
Macro to conveniently test info output and log it.
Definition: macros.h:20
bool hasObjectId(const db::AuditEntryCollection &audit_entries, const uint64_t &object_id)
Checks if an object is in a collection od audit entries.
Definition: cb_ctl_base.h:364
boost::shared_ptr< AuditEntryCollection > AuditEntryCollectionPtr
Definition: audit_entry.h:294
boost::shared_ptr< SrvConfig > SrvConfigPtr
Non-const pointer to the SrvConfig.
Definition: srv_config.h:1165
boost::shared_ptr< const CfgGlobals > ConstCfgGlobalsPtr
Const shared pointer to a CfgGlobals instance.
Definition: cfg_globals.h:159
Maintains a list of ClientClassDef&#39;s.
boost::multi_index_container< OptionDefinitionPtr, boost::multi_index::indexed_by< boost::multi_index::sequenced<>, boost::multi_index::hashed_non_unique< boost::multi_index::const_mem_fun< OptionDefinition, uint16_t, &OptionDefinition::getCode > >, boost::multi_index::hashed_non_unique< boost::multi_index::const_mem_fun< OptionDefinition, std::string, &OptionDefinition::getName > >, boost::multi_index::ordered_non_unique< boost::multi_index::const_mem_fun< data::BaseStampedElement, boost::posix_time::ptime, &data::StampedElement::getModificationTime > >, boost::multi_index::hashed_non_unique< boost::multi_index::tag< OptionIdIndexTag >, boost::multi_index::const_mem_fun< data::BaseStampedElement, uint64_t, &data::BaseStampedElement::getId > > >> OptionDefContainer
Multi index container for DHCP option definitions.
boost::multi_index_container< Subnet4Ptr, boost::multi_index::indexed_by< boost::multi_index::ordered_unique< boost::multi_index::tag< SubnetSubnetIdIndexTag >, boost::multi_index::const_mem_fun< Subnet, SubnetID, &Subnet::getID > >, boost::multi_index::ordered_unique< boost::multi_index::tag< SubnetPrefixIndexTag >, boost::multi_index::const_mem_fun< Subnet, std::string, &Subnet::toText > >, boost::multi_index::ordered_non_unique< boost::multi_index::tag< SubnetServerIdIndexTag >, boost::multi_index::const_mem_fun< Network4, asiolink::IOAddress, &Network4::getServerId > >, boost::multi_index::ordered_non_unique< boost::multi_index::tag< SubnetModificationTimeIndexTag >, boost::multi_index::const_mem_fun< data::BaseStampedElement, boost::posix_time::ptime, &data::BaseStampedElement::getModificationTime > > >> Subnet4Collection
A collection of Subnet4 objects.
Definition: subnet.h:893
Wrapper class around callout handle which automatically resets handle&#39;s state.
Server selector for associating objects in a database with specific servers.
void createOptions(const CfgOptionDefPtr &cfg_option_def)
Iterates over the classes in the dictionary and recreates the options.
boost::shared_ptr< SharedNetwork4 > SharedNetwork4Ptr
Pointer to SharedNetwork4 object.
Defines the logger used by the top-level component of kea-lfc.
boost::multi_index_container< StampedValuePtr, boost::multi_index::indexed_by< boost::multi_index::hashed_non_unique< boost::multi_index::tag< StampedValueNameIndexTag >, boost::multi_index::const_mem_fun< StampedValue, std::string, &StampedValue::getName > >, boost::multi_index::ordered_non_unique< boost::multi_index::tag< StampedValueModificationTimeIndexTag >, boost::multi_index::const_mem_fun< BaseStampedElement, boost::posix_time::ptime, &BaseStampedElement::getModificationTime > > >> StampedValueCollection
Multi index container for StampedValue.
boost::multi_index_container< SharedNetwork4Ptr, boost::multi_index::indexed_by< boost::multi_index::random_access< boost::multi_index::tag< SharedNetworkRandomAccessIndexTag > >, boost::multi_index::hashed_non_unique< boost::multi_index::tag< SharedNetworkIdIndexTag >, boost::multi_index::const_mem_fun< data::BaseStampedElement, uint64_t, &data::BaseStampedElement::getId > >, boost::multi_index::ordered_unique< boost::multi_index::tag< SharedNetworkNameIndexTag >, boost::multi_index::const_mem_fun< SharedNetwork4, std::string, &SharedNetwork4::getName > >, boost::multi_index::ordered_non_unique< boost::multi_index::tag< SharedNetworkServerIdIndexTag >, boost::multi_index::const_mem_fun< Network4, asiolink::IOAddress, &Network4::getServerId > >, boost::multi_index::ordered_non_unique< boost::multi_index::tag< SharedNetworkModificationTimeIndexTag >, boost::multi_index::const_mem_fun< data::BaseStampedElement, boost::posix_time::ptime, &data::BaseStampedElement::getModificationTime > > >> SharedNetwork4Collection
Multi index container holding shared networks.
Config Backend selector.
boost::shared_ptr< CalloutHandle > CalloutHandlePtr
A shared pointer to a CalloutHandle object.
boost::multi_index_container< OptionDescriptor, boost::multi_index::indexed_by< boost::multi_index::sequenced<>, boost::multi_index::hashed_non_unique< KeyFromKeyExtractor< boost::multi_index::const_mem_fun< Option, uint16_t, &Option::getType >, boost::multi_index::member< OptionDescriptor, OptionPtr, &OptionDescriptor::option_ > > >, boost::multi_index::hashed_non_unique< boost::multi_index::member< OptionDescriptor, bool, &OptionDescriptor::persistent_ > >, boost::multi_index::ordered_non_unique< boost::multi_index::const_mem_fun< data::BaseStampedElement, boost::posix_time::ptime, &data::BaseStampedElement::getModificationTime > >, boost::multi_index::hashed_non_unique< boost::multi_index::tag< OptionIdIndexTag >, boost::multi_index::const_mem_fun< data::BaseStampedElement, uint64_t, &data::BaseStampedElement::getId > > >> OptionContainer
Multi index container for DHCP option descriptors.
Definition: cfg_option.h:269
const isc::log::MessageID DHCPSRV_CFGMGR_IPV4_RESERVATIONS_NON_UNIQUE_IGNORED
isc::log::Logger dhcpsrv_logger("dhcpsrv")
DHCP server library Logger.
Definition: dhcpsrv_log.h:56
void initMatchExpr(uint16_t family)
Iterates over the classes in the dictionary and ensures that that match expressions are initialized...
Defines classes for storing client class definitions.
boost::multi_index_container< AuditEntryPtr, boost::multi_index::indexed_by< boost::multi_index::ordered_non_unique< boost::multi_index::tag< AuditEntryObjectTypeTag >, boost::multi_index::composite_key< AuditEntry, boost::multi_index::const_mem_fun< AuditEntry, std::string, &AuditEntry::getObjectType >, boost::multi_index::const_mem_fun< AuditEntry, AuditEntry::ModificationType, &AuditEntry::getModificationType > > >, boost::multi_index::ordered_non_unique< boost::multi_index::tag< AuditEntryModificationTimeIdTag >, boost::multi_index::composite_key< AuditEntry, boost::multi_index::const_mem_fun< AuditEntry, boost::posix_time::ptime, &AuditEntry::getModificationTime >, boost::multi_index::const_mem_fun< AuditEntry, uint64_t, &AuditEntry::getRevisionId > > >, boost::multi_index::hashed_non_unique< boost::multi_index::tag< AuditEntryObjectIdTag >, boost::multi_index::const_mem_fun< AuditEntry, uint64_t, &AuditEntry::getObjectId > > >> AuditEntryCollection
Multi index container holding AuditEntry instances.
Definition: audit_entry.h:291
Tag used to access index by object type.
Definition: audit_entry.h:229