commit 893a991ac27240178e736214b981910291c1833b
author Alice Wang <aliceywang@google.com> Mon Oct 24 10:44:09 2022 +0000
committer Alice Wang <aliceywang@google.com> Thu Nov 10 15:39:59 2022 +0000
tree f28f07bac9bab9219779193464c0d3555f48039b
parent 24e5102013bc9f46a8a49564de3a9bc186f7c115

[rpc_binder] Implement RPC binder over init-managed Unix domain socket

This implements an RPC binder over init-managed Unix domain sockets.
The cl adds binder tests and the new API is also used for
vm_payload_service inside Microdroid.
A previous cl aosp/2229557 sets up the binder over anonymous Unix sockets.

Test: atest MicrodroidTests ComposHostTestCases
Bug: 222479468
Change-Id: I0c7c38f4792c4536f5f88eb7e035091505f782f7

libs/binder/libbinder_rpc_unstable.cpp

diff --git a/libs/binder/libbinder_rpc_unstable.cpp b/libs/binder/libbinder_rpc_unstable.cpp
index 1f38bb9..ae07aee 100644
--- a/libs/binder/libbinder_rpc_unstable.cpp
+++ b/libs/binder/libbinder_rpc_unstable.cpp
@@ -19,6 +19,7 @@
 #include <android/binder_libbinder.h>
 #include <binder/RpcServer.h>
 #include <binder/RpcSession.h>
+#include <cutils/sockets.h>
 #include <linux/vm_sockets.h>
 
 using android::OK;
@@ -30,6 +31,17 @@
 
 extern "C" {
 
+void RunRpcServer(android::sp<RpcServer>& server, AIBinder* service,
+                  void (*readyCallback)(void* param), void* param) {
+    server->setRootObject(AIBinder_toPlatformBinder(service));
+
+    if (readyCallback) readyCallback(param);
+    server->join();
+
+    // Shutdown any open sessions since server failed.
+    (void)server->shutdown();
+}
+
 bool RunVsockRpcServerWithFactory(AIBinder* (*factory)(unsigned int cid, void* context),
                                   void* factoryContext, unsigned int port) {
     auto server = RpcServer::make();
@@ -60,13 +72,7 @@
                    << " error: " << statusToString(status).c_str();
         return false;
     }
-    server->setRootObject(AIBinder_toPlatformBinder(service));
-
-    if (readyCallback) readyCallback(param);
-    server->join();
-
-    // Shutdown any open sessions since server failed.
-    (void)server->shutdown();
+    RunRpcServer(server, service, readyCallback, param);
     return true;
 }
 
@@ -84,6 +90,31 @@
     return AIBinder_fromPlatformBinder(session->getRootObject());
 }
 
+bool RunInitUnixDomainRpcServer(AIBinder* service, const char* name,
+                                void (*readyCallback)(void* param), void* param) {
+    auto server = RpcServer::make();
+    auto fd = unique_fd(android_get_control_socket(name));
+    if (status_t status = server->setupRawSocketServer(std::move(fd)); status != OK) {
+        LOG(ERROR) << "Failed to set up Unix Domain RPC server with name " << name
+                   << " error: " << statusToString(status).c_str();
+        return false;
+    }
+    RunRpcServer(server, service, readyCallback, param);
+    return true;
+}
+
+AIBinder* UnixDomainRpcClient(const char* name) {
+    std::string pathname(name);
+    pathname = ANDROID_SOCKET_DIR "/" + pathname;
+    auto session = RpcSession::make();
+    if (status_t status = session->setupUnixDomainClient(pathname.c_str()); status != OK) {
+        LOG(ERROR) << "Failed to set up Unix Domain RPC client with path: " << pathname
+                   << " error: " << statusToString(status).c_str();
+        return nullptr;
+    }
+    return AIBinder_fromPlatformBinder(session->getRootObject());
+}
+
 AIBinder* RpcPreconnectedClient(int (*requestFd)(void* param), void* param) {
     auto session = RpcSession::make();
     auto request = [=] { return unique_fd{requestFd(param)}; };