Add HmacKeyManager to InputDispatcher
This class will be used to sign pieces of MotionEvent and MotionEntry.
Bug: 134977432
Test: atest libinput_tests inputflinger_tests
Change-Id: Ica006edc5b049e1d5d894de255866eedb9cbb0e2
diff --git a/services/inputflinger/tests/InputDispatcher_test.cpp b/services/inputflinger/tests/InputDispatcher_test.cpp
index 27db8f5..c4092cd 100644
--- a/services/inputflinger/tests/InputDispatcher_test.cpp
+++ b/services/inputflinger/tests/InputDispatcher_test.cpp
@@ -43,6 +43,18 @@
float y;
};
+/**
+ * Return a DOWN key event with KEYCODE_A.
+ */
+static KeyEvent getTestKeyEvent() {
+ KeyEvent event;
+
+ event.initialize(DEVICE_ID, AINPUT_SOURCE_KEYBOARD, ADISPLAY_ID_NONE, INVALID_HMAC,
+ AKEY_EVENT_ACTION_DOWN, 0, AKEYCODE_A, KEY_A, AMETA_NONE, 0, ARBITRARY_TIME,
+ ARBITRARY_TIME);
+ return event;
+}
+
// --- FakeInputDispatcherPolicy ---
class FakeInputDispatcherPolicy : public InputDispatcherPolicyInterface {
@@ -197,6 +209,69 @@
}
};
+// --- HmacKeyManagerTest ---
+
+class HmacKeyManagerTest : public testing::Test {
+protected:
+ HmacKeyManager mHmacKeyManager;
+};
+
+/**
+ * Ensure that separate calls to sign the same data are generating the same key.
+ * We avoid asserting against INVALID_HMAC. Since the key is random, there is a non-zero chance
+ * that a specific key and data combination would produce INVALID_HMAC, which would cause flaky
+ * tests.
+ */
+TEST_F(HmacKeyManagerTest, GeneratedHmac_IsConsistent) {
+ KeyEvent event = getTestKeyEvent();
+ VerifiedKeyEvent verifiedEvent = verifiedKeyEventFromKeyEvent(event);
+
+ std::array<uint8_t, 32> hmac1 = mHmacKeyManager.sign(verifiedEvent);
+ std::array<uint8_t, 32> hmac2 = mHmacKeyManager.sign(verifiedEvent);
+ ASSERT_EQ(hmac1, hmac2);
+}
+
+/**
+ * Ensure that changes in VerifiedKeyEvent produce a different hmac.
+ */
+TEST_F(HmacKeyManagerTest, GeneratedHmac_ChangesWhenFieldsChange) {
+ KeyEvent event = getTestKeyEvent();
+ VerifiedKeyEvent verifiedEvent = verifiedKeyEventFromKeyEvent(event);
+ std::array<uint8_t, 32> initialHmac = mHmacKeyManager.sign(verifiedEvent);
+
+ verifiedEvent.deviceId += 1;
+ ASSERT_NE(initialHmac, mHmacKeyManager.sign(verifiedEvent));
+
+ verifiedEvent.source += 1;
+ ASSERT_NE(initialHmac, mHmacKeyManager.sign(verifiedEvent));
+
+ verifiedEvent.eventTimeNanos += 1;
+ ASSERT_NE(initialHmac, mHmacKeyManager.sign(verifiedEvent));
+
+ verifiedEvent.displayId += 1;
+ ASSERT_NE(initialHmac, mHmacKeyManager.sign(verifiedEvent));
+
+ verifiedEvent.action += 1;
+ ASSERT_NE(initialHmac, mHmacKeyManager.sign(verifiedEvent));
+
+ verifiedEvent.downTimeNanos += 1;
+ ASSERT_NE(initialHmac, mHmacKeyManager.sign(verifiedEvent));
+
+ verifiedEvent.flags += 1;
+ ASSERT_NE(initialHmac, mHmacKeyManager.sign(verifiedEvent));
+
+ verifiedEvent.keyCode += 1;
+ ASSERT_NE(initialHmac, mHmacKeyManager.sign(verifiedEvent));
+
+ verifiedEvent.scanCode += 1;
+ ASSERT_NE(initialHmac, mHmacKeyManager.sign(verifiedEvent));
+
+ verifiedEvent.metaState += 1;
+ ASSERT_NE(initialHmac, mHmacKeyManager.sign(verifiedEvent));
+
+ verifiedEvent.repeatCount += 1;
+ ASSERT_NE(initialHmac, mHmacKeyManager.sign(verifiedEvent));
+}
// --- InputDispatcherTest ---