ueventd: allow using external firmware handlers
Userspace may want to load a different firmware than the one that the
kernel requests in some cases, therefore this change adds the ability
to ueventd to run an external handler that will determine the name of
the file that should actually be loaded.
Bug: 138352500
Test: unit tests
Change-Id: Ic5da37268fd78109f83ae52d1b903bf7322a5ee5
diff --git a/init/ueventd_parser.cpp b/init/ueventd_parser.cpp
index 1ca1715..a74b247 100644
--- a/init/ueventd_parser.cpp
+++ b/init/ueventd_parser.cpp
@@ -88,6 +88,31 @@
return {};
}
+Result<void> ParseExternalFirmwareHandlerLine(
+ std::vector<std::string>&& args,
+ std::vector<ExternalFirmwareHandler>* external_firmware_handlers) {
+ if (args.size() != 4) {
+ return Error() << "external_firmware_handler lines must have exactly 3 parameters";
+ }
+
+ if (std::find_if(external_firmware_handlers->begin(), external_firmware_handlers->end(),
+ [&args](const auto& other) { return other.devpath == args[2]; }) !=
+ external_firmware_handlers->end()) {
+ return Error() << "found a previous external_firmware_handler with the same devpath, '"
+ << args[2] << "'";
+ }
+
+ passwd* pwd = getpwnam(args[2].c_str());
+ if (!pwd) {
+ return ErrnoError() << "invalid handler uid'" << args[2] << "'";
+ }
+
+ ExternalFirmwareHandler handler(std::move(args[1]), pwd->pw_uid, std::move(args[3]));
+ external_firmware_handlers->emplace_back(std::move(handler));
+
+ return {};
+}
+
Result<void> ParseEnabledDisabledLine(std::vector<std::string>&& args, bool* feature) {
if (args.size() != 2) {
return Error() << args[0] << " lines take exactly one parameter";
@@ -211,6 +236,9 @@
parser.AddSingleLineParser("firmware_directories",
std::bind(ParseFirmwareDirectoriesLine, _1,
&ueventd_configuration.firmware_directories));
+ parser.AddSingleLineParser("external_firmware_handler",
+ std::bind(ParseExternalFirmwareHandlerLine, _1,
+ &ueventd_configuration.external_firmware_handlers));
parser.AddSingleLineParser("modalias_handling",
std::bind(ParseEnabledDisabledLine, _1,
&ueventd_configuration.enable_modalias_handling));