diff options
| author | tyiu <tyiu@google.com> | 2023-02-21 22:38:32 +0000 |
|---|---|---|
| committer | Timothy Yiu <tyiu@google.com> | 2023-03-15 04:07:55 +0000 |
| commit | ca8d670c1656a6a47ef0f31fdfe1744d75fe5543 (patch) | |
| tree | 7abe60c0b7958e718226f4fac3ab4120693b5426 | |
| parent | 0905d59160e5cd5ff7bf63261c7b5cad6b875b9a (diff) | |
| download | native-ca8d670c1656a6a47ef0f31fdfe1744d75fe5543.tar.gz | |
RESTRICT AUTOMERGE: Fix HMAC Compare time attack
Added constant time HMAC comparison preventing attackers being able to
forge HMAC for input by measuring the time difference between
non-constant time comparison of HMAC
Bug: 261085213
Test: None
Tag: #security
Change-Id: I7cd6b68589fd0042b9396dc599b917a0f3220ff7
| -rw-r--r-- | services/inputflinger/dispatcher/InputDispatcher.cpp | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/services/inputflinger/dispatcher/InputDispatcher.cpp b/services/inputflinger/dispatcher/InputDispatcher.cpp index 5e9427ad87..da461285f5 100644 --- a/services/inputflinger/dispatcher/InputDispatcher.cpp +++ b/services/inputflinger/dispatcher/InputDispatcher.cpp @@ -27,6 +27,7 @@ #include <ftl/enum.h> #include <gui/SurfaceComposerClient.h> #include <input/InputDevice.h> +#include <openssl/mem.h> #include <powermanager/PowerManager.h> #include <unistd.h> #include <utils/Trace.h> @@ -4422,7 +4423,7 @@ std::unique_ptr<VerifiedInputEvent> InputDispatcher::verifyInputEvent(const Inpu if (calculatedHmac == INVALID_HMAC) { return nullptr; } - if (calculatedHmac != event.getHmac()) { + if (0 != CRYPTO_memcmp(calculatedHmac.data(), event.getHmac().data(), calculatedHmac.size())) { return nullptr; } return result; |