1 // SPDX-License-Identifier: Apache-2.0 2 3 /**@file functions.cpp*/ 4 5 #include "functions.hpp" 6 7 #include <sdbusplus/bus.hpp> 8 #include <sdbusplus/bus/match.hpp> 9 #include <sdbusplus/exception.hpp> 10 #include <sdbusplus/message.hpp> 11 #include <sdeventplus/event.hpp> 12 13 #include <filesystem> 14 #include <functional> 15 #include <iostream> 16 #include <map> 17 #include <memory> 18 #include <string> 19 #include <variant> 20 #include <vector> 21 22 namespace functions 23 { 24 namespace process_hostfirmware 25 { 26 27 /** 28 * @brief Issue callbacks safely 29 * 30 * std::function can be empty, so this wrapper method checks for that prior to 31 * calling it to avoid std::bad_function_call 32 * 33 * @tparam Sig the types of the std::function arguments 34 * @tparam Args the deduced argument types 35 * @param[in] callback the callback being wrapped 36 * @param[in] args the callback arguments 37 */ 38 template <typename... Sig, typename... Args> 39 void makeCallback(const std::function<void(Sig...)>& callback, Args&&... args) 40 { 41 if (callback) 42 { 43 callback(std::forward<Args>(args)...); 44 } 45 } 46 47 /** 48 * @brief Get file extensions for IBMCompatibleSystem 49 * 50 * IBM host firmware can be deployed as blobs (files) in a filesystem. Host 51 * firmware blobs for different values of 52 * xyz.openbmc_project.Configuration.IBMCompatibleSystem are packaged with 53 * different filename extensions. getExtensionsForIbmCompatibleSystem 54 * maintains the mapping from a given value of 55 * xyz.openbmc_project.Configuration.IBMCompatibleSystem to an array of 56 * filename extensions. 57 * 58 * If a mapping is found getExtensionsForIbmCompatibleSystem returns true and 59 * the extensions parameter is reset with the map entry. If no mapping is 60 * found getExtensionsForIbmCompatibleSystem returns false and extensions is 61 * unmodified. 62 * 63 * @param[in] extensionMap a map of 64 * xyz.openbmc_project.Configuration.IBMCompatibleSystem to host firmware blob 65 * file extensions. 66 * @param[in] ibmCompatibleSystem The names property of an instance of 67 * xyz.openbmc_project.Configuration.IBMCompatibleSystem 68 * @param[out] extentions the host firmware blob file extensions 69 * @return true if an entry was found, otherwise false 70 */ 71 bool getExtensionsForIbmCompatibleSystem( 72 const std::map<std::string, std::vector<std::string>>& extensionMap, 73 const std::vector<std::string>& ibmCompatibleSystem, 74 std::vector<std::string>& extensions) 75 { 76 for (const auto& system : ibmCompatibleSystem) 77 { 78 auto extensionMapIterator = extensionMap.find(system); 79 if (extensionMapIterator != extensionMap.end()) 80 { 81 extensions = extensionMapIterator->second; 82 return true; 83 } 84 } 85 86 return false; 87 } 88 89 /** 90 * @brief Write host firmware well-known name 91 * 92 * A wrapper around std::filesystem::create_symlink that avoids EEXIST by 93 * deleting any pre-existing file. 94 * 95 * @param[in] linkTarget The link target argument to 96 * std::filesystem::create_symlink 97 * @param[in] linkPath The link path argument to std::filesystem::create_symlink 98 * @param[in] errorCallback A callback made in the event of filesystem errors. 99 */ 100 void writeLink(const std::filesystem::path& linkTarget, 101 const std::filesystem::path& linkPath, 102 const ErrorCallbackType& errorCallback) 103 { 104 std::error_code ec; 105 106 // remove files with the same name as the symlink to be created, 107 // otherwise symlink will fail with EEXIST. 108 if (!std::filesystem::remove(linkPath, ec)) 109 { 110 if (ec) 111 { 112 makeCallback(errorCallback, linkPath, ec); 113 return; 114 } 115 } 116 117 std::filesystem::create_symlink(linkTarget, linkPath, ec); 118 if (ec) 119 { 120 makeCallback(errorCallback, linkPath, ec); 121 return; 122 } 123 } 124 125 /** 126 * @brief Find host firmware blob files that need well-known names 127 * 128 * The IBM host firmware runtime looks for data and/or additional code while 129 * bootstraping in files with well-known names. findLinks uses the provided 130 * extensions argument to find host firmware blob files that require a 131 * well-known name. When a blob is found, issue the provided callback 132 * (typically a function that will write a symlink). 133 * 134 * @param[in] hostFirmwareDirectory The directory in which findLinks should 135 * look for host firmware blob files that need well-known names. 136 * @param[in] extentions The extensions of the firmware blob files denote a 137 * host firmware blob file requires a well-known name. 138 * @param[in] errorCallback A callback made in the event of filesystem errors. 139 * @param[in] linkCallback A callback made when host firmware blob files 140 * needing a well known name are found. 141 */ 142 void findLinks(const std::filesystem::path& hostFirmwareDirectory, 143 const std::vector<std::string>& extensions, 144 const ErrorCallbackType& errorCallback, 145 const LinkCallbackType& linkCallback) 146 { 147 std::error_code ec; 148 std::filesystem::directory_iterator directoryIterator(hostFirmwareDirectory, 149 ec); 150 if (ec) 151 { 152 makeCallback(errorCallback, hostFirmwareDirectory, ec); 153 return; 154 } 155 156 // Create a symlink from HBB to the corresponding LID file if it exists 157 static const auto hbbLid = "81e0065a.lid"; 158 auto hbbLidPath = hostFirmwareDirectory / hbbLid; 159 if (std::filesystem::exists(hbbLidPath)) 160 { 161 static const auto hbbName = "HBB"; 162 auto hbbLinkPath = hostFirmwareDirectory / hbbName; 163 makeCallback(linkCallback, hbbLid, hbbLinkPath, errorCallback); 164 } 165 166 for (; directoryIterator != std::filesystem::end(directoryIterator); 167 directoryIterator.increment(ec)) 168 { 169 const auto& file = directoryIterator->path(); 170 if (ec) 171 { 172 makeCallback(errorCallback, file, ec); 173 // quit here if the increment call failed otherwise the loop may 174 // never finish 175 break; 176 } 177 178 if (std::find(extensions.begin(), extensions.end(), file.extension()) == 179 extensions.end()) 180 { 181 // this file doesn't have an extension or doesn't match any of the 182 // provided extensions. 183 continue; 184 } 185 186 auto linkPath(file.parent_path().append( 187 static_cast<const std::string&>(file.stem()))); 188 189 makeCallback(linkCallback, file.filename(), linkPath, errorCallback); 190 } 191 } 192 193 /** 194 * @brief Make callbacks on 195 * xyz.openbmc_project.Configuration.IBMCompatibleSystem instances. 196 * 197 * Look for an instance of 198 * xyz.openbmc_project.Configuration.IBMCompatibleSystem in the provided 199 * argument and if found, issue the provided callback. 200 * 201 * @param[in] interfacesAndProperties the interfaces in which to look for an 202 * instance of xyz.openbmc_project.Configuration.IBMCompatibleSystem 203 * @param[in] callback the user callback to make if 204 * xyz.openbmc_project.Configuration.IBMCompatibleSystem is found in 205 * interfacesAndProperties 206 * @return true if interfacesAndProperties contained an instance of 207 * xyz.openbmc_project.Configuration.IBMCompatibleSystem, false otherwise 208 */ 209 bool maybeCall(const std::map<std::string, 210 std::map<std::string, 211 std::variant<std::vector<std::string>>>>& 212 interfacesAndProperties, 213 const MaybeCallCallbackType& callback) 214 { 215 using namespace std::string_literals; 216 217 static const auto interfaceName = 218 "xyz.openbmc_project.Configuration.IBMCompatibleSystem"s; 219 auto interfaceIterator = interfacesAndProperties.find(interfaceName); 220 if (interfaceIterator == interfacesAndProperties.cend()) 221 { 222 // IBMCompatibleSystem interface not found, so instruct the caller to 223 // keep waiting or try again later. 224 return false; 225 } 226 auto propertyIterator = interfaceIterator->second.find("Names"s); 227 if (propertyIterator == interfaceIterator->second.cend()) 228 { 229 // The interface exists but the property doesn't. This is a bug in the 230 // IBMCompatibleSystem implementation. The caller should not try 231 // again. 232 std::cerr << "Names property not implemented on " << interfaceName 233 << "\n"; 234 return true; 235 } 236 237 const auto& ibmCompatibleSystem = 238 std::get<std::vector<std::string>>(propertyIterator->second); 239 if (callback) 240 { 241 callback(ibmCompatibleSystem); 242 } 243 244 // IBMCompatibleSystem found and callback issued. 245 return true; 246 } 247 248 /** 249 * @brief Make callbacks on 250 * xyz.openbmc_project.Configuration.IBMCompatibleSystem instances. 251 * 252 * Look for an instance of 253 * xyz.openbmc_project.Configuration.IBMCompatibleSystem in the provided 254 * argument and if found, issue the provided callback. 255 * 256 * @param[in] message the DBus message in which to look for an instance of 257 * xyz.openbmc_project.Configuration.IBMCompatibleSystem 258 * @param[in] callback the user callback to make if 259 * xyz.openbmc_project.Configuration.IBMCompatibleSystem is found in 260 * message 261 * @return true if message contained an instance of 262 * xyz.openbmc_project.Configuration.IBMCompatibleSystem, false otherwise 263 */ 264 bool maybeCallMessage(sdbusplus::message::message& message, 265 const MaybeCallCallbackType& callback) 266 { 267 std::map<std::string, 268 std::map<std::string, std::variant<std::vector<std::string>>>> 269 interfacesAndProperties; 270 sdbusplus::message::object_path _; 271 message.read(_, interfacesAndProperties); 272 return maybeCall(interfacesAndProperties, callback); 273 } 274 275 /** 276 * @brief Determine system support for host firmware well-known names. 277 * 278 * Using the provided extensionMap and 279 * xyz.openbmc_project.Configuration.IBMCompatibleSystem, determine if 280 * well-known names for host firmare blob files are necessary and if so, create 281 * them. 282 * 283 * @param[in] extensionMap a map of 284 * xyz.openbmc_project.Configuration.IBMCompatibleSystem to host firmware blob 285 * file extensions. 286 * @param[in] hostFirmwareDirectory The directory in which findLinks should 287 * look for host firmware blob files that need well-known names. 288 * @param[in] ibmCompatibleSystem The names property of an instance of 289 * xyz.openbmc_project.Configuration.IBMCompatibleSystem 290 * @param[in] errorCallback A callback made in the event of filesystem errors. 291 */ 292 void maybeMakeLinks( 293 const std::map<std::string, std::vector<std::string>>& extensionMap, 294 const std::filesystem::path& hostFirmwareDirectory, 295 const std::vector<std::string>& ibmCompatibleSystem, 296 const ErrorCallbackType& errorCallback) 297 { 298 std::vector<std::string> extensions; 299 if (getExtensionsForIbmCompatibleSystem(extensionMap, ibmCompatibleSystem, 300 extensions)) 301 { 302 findLinks(hostFirmwareDirectory, extensions, errorCallback, writeLink); 303 } 304 } 305 306 /** 307 * @brief process host firmware 308 * 309 * Allocate a callback context and register for DBus.ObjectManager Interfaces 310 * added signals from entity manager. 311 * 312 * Check the current entity manager object tree for a 313 * xyz.openbmc_project.Configuration.IBMCompatibleSystem instance (entity 314 * manager will be dbus activated if it is not running). If one is found, 315 * determine if symlinks need to be created and create them. Instruct the 316 * program event loop to exit. 317 * 318 * If no instance of xyz.openbmc_project.Configuration.IBMCompatibleSystem is 319 * found return the callback context to main, where the program will sleep 320 * until the callback is invoked one or more times and instructs the program 321 * event loop to exit when 322 * xyz.openbmc_project.Configuration.IBMCompatibleSystem is added. 323 * 324 * @param[in] bus a DBus client connection 325 * @param[in] extensionMap a map of 326 * xyz.openbmc_project.Configuration.IBMCompatibleSystem to host firmware blob 327 * file extensions. 328 * @param[in] hostFirmwareDirectory The directory in which processHostFirmware 329 * should look for blob files. 330 * @param[in] errorCallback A callback made in the event of filesystem errors. 331 * @param[in] loop a program event loop 332 * @return nullptr if an instance of 333 * xyz.openbmc_project.Configuration.IBMCompatibleSystem is found, otherwise a 334 * pointer to an sdbusplus match object. 335 */ 336 std::shared_ptr<void> processHostFirmware( 337 sdbusplus::bus::bus& bus, 338 std::map<std::string, std::vector<std::string>> extensionMap, 339 std::filesystem::path hostFirmwareDirectory, 340 ErrorCallbackType errorCallback, sdeventplus::Event& loop) 341 { 342 // ownership of extensionMap, hostFirmwareDirectory and errorCallback can't 343 // be transfered to the match callback because they are needed in the non 344 // async part of this function below, so they need to be moved to the heap. 345 auto pExtensionMap = 346 std::make_shared<decltype(extensionMap)>(std::move(extensionMap)); 347 auto pHostFirmwareDirectory = 348 std::make_shared<decltype(hostFirmwareDirectory)>( 349 std::move(hostFirmwareDirectory)); 350 auto pErrorCallback = 351 std::make_shared<decltype(errorCallback)>(std::move(errorCallback)); 352 353 // register for a callback in case the IBMCompatibleSystem interface has 354 // not yet been published by entity manager. 355 auto interfacesAddedMatch = std::make_shared<sdbusplus::bus::match::match>( 356 bus, 357 sdbusplus::bus::match::rules::interfacesAdded() + 358 sdbusplus::bus::match::rules::sender( 359 "xyz.openbmc_project.EntityManager"), 360 [pExtensionMap, pHostFirmwareDirectory, pErrorCallback, 361 &loop](auto& message) { 362 // bind the extension map, host firmware directory, and error 363 // callback to the maybeMakeLinks function. 364 auto maybeMakeLinksWithArgsBound = 365 std::bind(maybeMakeLinks, std::cref(*pExtensionMap), 366 std::cref(*pHostFirmwareDirectory), 367 std::placeholders::_1, std::cref(*pErrorCallback)); 368 369 // if the InterfacesAdded message contains an an instance of 370 // xyz.openbmc_project.Configuration.IBMCompatibleSystem, check to 371 // see if links are necessary on this system and if so, create 372 // them. 373 if (maybeCallMessage(message, maybeMakeLinksWithArgsBound)) 374 { 375 // The IBMCompatibleSystem interface was found and the links 376 // were created if applicable. Instruct the event loop / 377 // subcommand to exit. 378 loop.exit(0); 379 } 380 }); 381 382 // now that we'll get a callback in the event of an InterfacesAdded signal 383 // (potentially containing 384 // xyz.openbmc_project.Configuration.IBMCompatibleSystem), activate entity 385 // manager if it isn't running and enumerate its objects 386 auto getManagedObjects = bus.new_method_call( 387 "xyz.openbmc_project.EntityManager", "/", 388 "org.freedesktop.DBus.ObjectManager", "GetManagedObjects"); 389 std::map<std::string, 390 std::map<std::string, std::variant<std::vector<std::string>>>> 391 interfacesAndProperties; 392 std::map<sdbusplus::message::object_path, decltype(interfacesAndProperties)> 393 objects; 394 try 395 { 396 auto reply = bus.call(getManagedObjects); 397 reply.read(objects); 398 } 399 catch (const sdbusplus::exception::SdBusError& e) 400 { 401 // Error querying the EntityManager interface. Return the match to have 402 // the callback run if/when the interface appears in D-Bus. 403 return interfacesAddedMatch; 404 } 405 406 // bind the extension map, host firmware directory, and error callback to 407 // the maybeMakeLinks function. 408 auto maybeMakeLinksWithArgsBound = 409 std::bind(maybeMakeLinks, std::cref(*pExtensionMap), 410 std::cref(*pHostFirmwareDirectory), std::placeholders::_1, 411 std::cref(*pErrorCallback)); 412 413 for (const auto& pair : objects) 414 { 415 std::tie(std::ignore, interfacesAndProperties) = pair; 416 // if interfacesAndProperties contains an an instance of 417 // xyz.openbmc_project.Configuration.IBMCompatibleSystem, check to see 418 // if links are necessary on this system and if so, create them 419 if (maybeCall(interfacesAndProperties, maybeMakeLinksWithArgsBound)) 420 { 421 // The IBMCompatibleSystem interface is already on the bus and the 422 // links were created if applicable. Instruct the event loop to 423 // exit. 424 loop.exit(0); 425 // The match object isn't needed anymore, so destroy it on return. 426 return nullptr; 427 } 428 } 429 430 // The IBMCompatibleSystem interface has not yet been published. Move 431 // ownership of the match callback to the caller. 432 return interfacesAddedMatch; 433 } 434 } // namespace process_hostfirmware 435 } // namespace functions 436