libbinderwrapper: Add GetCallingUid() and GetCallingPid().

Add methods to BinderWrapper for getting the caller's UID
and PID while in a transaction.

Bug: 24988639
Change-Id: Ibd711fc6b3d83623d4bb1060838c65aaef30d76e

3 files changed, 22 insertions, 1 deletions

diff --git a/libbinderwrapper/real_binder_wrapper.cc b/libbinderwrapper/real_binder_wrapper.cc
index adff19bed..1c518226d 100644
--- a/libbinderwrapper/real_binder_wrapper.cc
+++ b/libbinderwrapper/real_binder_wrapper.cc
@@ -19,6 +19,7 @@
 #include <base/logging.h>
 #include <binder/Binder.h>
 #include <binder/IBinder.h>
+#include <binder/IPCThreadState.h>
 #include <binder/IServiceManager.h>
 
 namespace android {
@@ -111,4 +112,12 @@ bool RealBinderWrapper::UnregisterForDeathNotifications(
   return true;
 }
 
+uid_t RealBinderWrapper::GetCallingUid() {
+  return IPCThreadState::self()->getCallingUid();
+}
+
+pid_t RealBinderWrapper::GetCallingPid() {
+  return IPCThreadState::self()->getCallingPid();
+}
+
 }  // namespace android
diff --git a/libbinderwrapper/real_binder_wrapper.h b/libbinderwrapper/real_binder_wrapper.h
index 8e281f2f8..ea0837171 100644
--- a/libbinderwrapper/real_binder_wrapper.h
+++ b/libbinderwrapper/real_binder_wrapper.h
@@ -38,6 +38,8 @@ class RealBinderWrapper : public BinderWrapper {
   bool RegisterForDeathNotifications(const sp<IBinder>& binder,
                                      const base::Closure& callback) override;
   bool UnregisterForDeathNotifications(const sp<IBinder>& binder) override;
+  uid_t GetCallingUid() override;
+  pid_t GetCallingPid() override;
 
  private:
   class DeathRecipient;
diff --git a/libbinderwrapper/stub_binder_wrapper.cc b/libbinderwrapper/stub_binder_wrapper.cc
index 1d2468101..87c6ab793 100644
--- a/libbinderwrapper/stub_binder_wrapper.cc
+++ b/libbinderwrapper/stub_binder_wrapper.cc
@@ -22,7 +22,9 @@
 
 namespace android {
 
-StubBinderWrapper::StubBinderWrapper() = default;
+StubBinderWrapper::StubBinderWrapper()
+    : calling_uid_(-1),
+      calling_pid_(-1) {}
 
 StubBinderWrapper::~StubBinderWrapper() = default;
 
@@ -73,4 +75,12 @@ bool StubBinderWrapper::UnregisterForDeathNotifications(
   return true;
 }
 
+uid_t StubBinderWrapper::GetCallingUid() {
+  return calling_uid_;
+}
+
+pid_t StubBinderWrapper::GetCallingPid() {
+  return calling_pid_;
+}
+
 }  // namespace android