From a3934aa5142ddcddf0d1b8a5cdc7d377197b8470 Mon Sep 17 00:00:00 2001 From: Jeff Brown Date: Mon, 11 Oct 2010 14:20:19 -0700 Subject: [PATCH] Fix an event injection bug when the policy is bypassed. Added the concept of a "trusted" event to distinguish between events from attached input devices or trusted injectors vs. other applications. This change enables us to move certain policy decisions out of the dispatcher and into the policy itself where they can be handled more systematically. Change-Id: I4d56fdcdd31aaa675d452088af39a70c4e039970 --- include/ui/Input.h | 4 +++ include/ui/InputDispatcher.h | 5 ++- libs/ui/InputDispatcher.cpp | 63 +++++++++++++++++------------------- 3 files changed, 36 insertions(+), 36 deletions(-) diff --git a/include/ui/Input.h b/include/ui/Input.h index 66061fd71..8c6018bfe 100644 --- a/include/ui/Input.h +++ b/include/ui/Input.h @@ -95,6 +95,10 @@ enum { // Indicates that the input event was injected. POLICY_FLAG_INJECTED = 0x01000000, + // Indicates that the input event is from a trusted source such as a directly attached + // input device or an application with system-wide event injection permission. + POLICY_FLAG_TRUSTED = 0x02000000, + /* These flags are set by the input reader policy as it intercepts each event. */ // Indicates that the screen was off when the event was received and the event diff --git a/include/ui/InputDispatcher.h b/include/ui/InputDispatcher.h index 0834e8650..3599163d1 100644 --- a/include/ui/InputDispatcher.h +++ b/include/ui/InputDispatcher.h @@ -913,7 +913,6 @@ private: void drainInboundQueueLocked(); void releasePendingEventLocked(); void releaseInboundEventLocked(EventEntry* entry); - bool isEventFromTrustedSourceLocked(EventEntry* entry); // Dispatch state. bool mDispatchEnabled; @@ -960,10 +959,10 @@ private: nsecs_t currentTime, ConfigurationChangedEntry* entry); bool dispatchKeyLocked( nsecs_t currentTime, KeyEntry* entry, nsecs_t keyRepeatTimeout, - bool dropEvent, nsecs_t* nextWakeupTime); + DropReason* dropReason, nsecs_t* nextWakeupTime); bool dispatchMotionLocked( nsecs_t currentTime, MotionEntry* entry, - bool dropEvent, nsecs_t* nextWakeupTime); + DropReason* dropReason, nsecs_t* nextWakeupTime); void dispatchEventToCurrentInputTargetsLocked( nsecs_t currentTime, EventEntry* entry, bool resumeWithAppendedMotionSample); diff --git a/libs/ui/InputDispatcher.cpp b/libs/ui/InputDispatcher.cpp index 58c2cdfda..41b6ff318 100644 --- a/libs/ui/InputDispatcher.cpp +++ b/libs/ui/InputDispatcher.cpp @@ -370,7 +370,7 @@ void InputDispatcher::dispatchOnceInnerLocked(nsecs_t keyRepeatTimeout, } } done = dispatchKeyLocked(currentTime, typedEntry, keyRepeatTimeout, - dropReason != DROP_REASON_NOT_DROPPED, nextWakeupTime); + &dropReason, nextWakeupTime); break; } @@ -380,7 +380,7 @@ void InputDispatcher::dispatchOnceInnerLocked(nsecs_t keyRepeatTimeout, dropReason = DROP_REASON_APP_SWITCH; } done = dispatchMotionLocked(currentTime, typedEntry, - dropReason != DROP_REASON_NOT_DROPPED, nextWakeupTime); + &dropReason, nextWakeupTime); break; } @@ -431,6 +431,9 @@ void InputDispatcher::dropInboundEventLocked(EventEntry* entry, DropReason dropR const char* reason; switch (dropReason) { case DROP_REASON_POLICY: +#if DEBUG_INBOUND_EVENT_DETAILS + LOGD("Dropped event because policy requested that it not be delivered to the application."); +#endif reason = "inbound event was dropped because the policy requested that it not be " "delivered to the application"; break; @@ -473,7 +476,7 @@ bool InputDispatcher::isAppSwitchKeyCode(int32_t keyCode) { bool InputDispatcher::isAppSwitchKeyEventLocked(KeyEntry* keyEntry) { return ! (keyEntry->flags & AKEY_EVENT_FLAG_CANCELED) && isAppSwitchKeyCode(keyEntry->keyCode) - && isEventFromTrustedSourceLocked(keyEntry) + && (keyEntry->policyFlags & POLICY_FLAG_TRUSTED) && (keyEntry->policyFlags & POLICY_FLAG_PASS_TO_USER); } @@ -541,12 +544,6 @@ void InputDispatcher::releaseInboundEventLocked(EventEntry* entry) { mAllocator.releaseEventEntry(entry); } -bool InputDispatcher::isEventFromTrustedSourceLocked(EventEntry* entry) { - InjectionState* injectionState = entry->injectionState; - return ! injectionState - || hasInjectionPermission(injectionState->injectorPid, injectionState->injectorUid); -} - void InputDispatcher::resetKeyRepeatLocked() { if (mKeyRepeatState.lastKeyEntry) { mAllocator.releaseKeyEntry(mKeyRepeatState.lastKeyEntry); @@ -559,7 +556,8 @@ InputDispatcher::KeyEntry* InputDispatcher::synthesizeKeyRepeatLocked( KeyEntry* entry = mKeyRepeatState.lastKeyEntry; // Reuse the repeated key entry if it is otherwise unreferenced. - uint32_t policyFlags = entry->policyFlags & (POLICY_FLAG_RAW_MASK | POLICY_FLAG_PASS_TO_USER); + uint32_t policyFlags = (entry->policyFlags & POLICY_FLAG_RAW_MASK) + | POLICY_FLAG_PASS_TO_USER | POLICY_FLAG_TRUSTED; if (entry->refCount == 1) { mAllocator.recycleKeyEntry(entry); entry->eventTime = currentTime; @@ -608,19 +606,13 @@ bool InputDispatcher::dispatchConfigurationChangedLocked( bool InputDispatcher::dispatchKeyLocked( nsecs_t currentTime, KeyEntry* entry, nsecs_t keyRepeatTimeout, - bool dropEvent, nsecs_t* nextWakeupTime) { + DropReason* dropReason, nsecs_t* nextWakeupTime) { // Give the policy a chance to intercept the key. if (entry->interceptKeyResult == KeyEntry::INTERCEPT_KEY_RESULT_UNKNOWN) { - bool trusted; - if (! dropEvent && mFocusedWindow) { - trusted = checkInjectionPermission(mFocusedWindow, entry->injectionState); - } else { - trusted = isEventFromTrustedSourceLocked(entry); - } - if (trusted) { + if (entry->policyFlags & POLICY_FLAG_PASS_TO_USER) { CommandEntry* commandEntry = postCommandLocked( & InputDispatcher::doInterceptKeyBeforeDispatchingLockedInterruptible); - if (! dropEvent && mFocusedWindow) { + if (mFocusedWindow) { commandEntry->inputChannel = mFocusedWindow->inputChannel; } commandEntry->keyEntry = entry; @@ -630,13 +622,16 @@ bool InputDispatcher::dispatchKeyLocked( entry->interceptKeyResult = KeyEntry::INTERCEPT_KEY_RESULT_CONTINUE; } } else if (entry->interceptKeyResult == KeyEntry::INTERCEPT_KEY_RESULT_SKIP) { + if (*dropReason == DROP_REASON_NOT_DROPPED) { + *dropReason = DROP_REASON_POLICY; + } resetTargetsLocked(); setInjectionResultLocked(entry, INPUT_EVENT_INJECTION_SUCCEEDED); return true; } // Clean up if dropping the event. - if (dropEvent) { + if (*dropReason != DROP_REASON_NOT_DROPPED) { resetTargetsLocked(); setInjectionResultLocked(entry, INPUT_EVENT_INJECTION_FAILED); return true; @@ -648,7 +643,8 @@ bool InputDispatcher::dispatchKeyLocked( if (entry->repeatCount == 0 && entry->action == AKEY_EVENT_ACTION_DOWN - && ! entry->isInjected()) { + && (entry->policyFlags & POLICY_FLAG_TRUSTED) + && !entry->isInjected()) { if (mKeyRepeatState.lastKeyEntry && mKeyRepeatState.lastKeyEntry->keyCode == entry->keyCode) { // We have seen two identical key downs in a row which indicates that the device @@ -713,9 +709,9 @@ void InputDispatcher::logOutboundKeyDetailsLocked(const char* prefix, const KeyE } bool InputDispatcher::dispatchMotionLocked( - nsecs_t currentTime, MotionEntry* entry, bool dropEvent, nsecs_t* nextWakeupTime) { + nsecs_t currentTime, MotionEntry* entry, DropReason* dropReason, nsecs_t* nextWakeupTime) { // Clean up if dropping the event. - if (dropEvent) { + if (*dropReason != DROP_REASON_NOT_DROPPED) { resetTargetsLocked(); setInjectionResultLocked(entry, INPUT_EVENT_INJECTION_FAILED); return true; @@ -2085,6 +2081,7 @@ void InputDispatcher::notifyKey(nsecs_t eventTime, int32_t deviceId, int32_t sou return; } + policyFlags |= POLICY_FLAG_TRUSTED; mPolicy->interceptKeyBeforeQueueing(eventTime, deviceId, action, /*byref*/ flags, keyCode, scanCode, /*byref*/ policyFlags); @@ -2130,6 +2127,7 @@ void InputDispatcher::notifyMotion(nsecs_t eventTime, int32_t deviceId, int32_t return; } + policyFlags |= POLICY_FLAG_TRUSTED; mPolicy->interceptGenericBeforeQueueing(eventTime, /*byref*/ policyFlags); bool needWake; @@ -2263,6 +2261,7 @@ void InputDispatcher::notifySwitch(nsecs_t when, int32_t switchCode, int32_t swi switchCode, switchValue, policyFlags); #endif + policyFlags |= POLICY_FLAG_TRUSTED; mPolicy->notifySwitch(when, switchCode, switchValue, policyFlags); } @@ -2275,7 +2274,11 @@ int32_t InputDispatcher::injectInputEvent(const InputEvent* event, #endif nsecs_t endTime = now() + milliseconds_to_nanoseconds(timeoutMillis); - bool trusted = hasInjectionPermission(injectorPid, injectorUid); + + uint32_t policyFlags = POLICY_FLAG_INJECTED; + if (hasInjectionPermission(injectorPid, injectorUid)) { + policyFlags |= POLICY_FLAG_TRUSTED; + } EventEntry* injectedEntry; switch (event->getType()) { @@ -2291,11 +2294,8 @@ int32_t InputDispatcher::injectInputEvent(const InputEvent* event, int32_t flags = keyEvent->getFlags(); int32_t keyCode = keyEvent->getKeyCode(); int32_t scanCode = keyEvent->getScanCode(); - uint32_t policyFlags = POLICY_FLAG_INJECTED; - if (trusted) { - mPolicy->interceptKeyBeforeQueueing(eventTime, deviceId, action, /*byref*/ flags, - keyCode, scanCode, /*byref*/ policyFlags); - } + mPolicy->interceptKeyBeforeQueueing(eventTime, deviceId, action, /*byref*/ flags, + keyCode, scanCode, /*byref*/ policyFlags); mLock.lock(); injectedEntry = mAllocator.obtainKeyEntry(eventTime, deviceId, keyEvent->getSource(), @@ -2314,10 +2314,7 @@ int32_t InputDispatcher::injectInputEvent(const InputEvent* event, } nsecs_t eventTime = motionEvent->getEventTime(); - uint32_t policyFlags = POLICY_FLAG_INJECTED; - if (trusted) { - mPolicy->interceptGenericBeforeQueueing(eventTime, /*byref*/ policyFlags); - } + mPolicy->interceptGenericBeforeQueueing(eventTime, /*byref*/ policyFlags); mLock.lock(); const nsecs_t* sampleEventTimes = motionEvent->getSampleEventTimes();