Add virtual Face HAL

Fixes: 230514750
Test: atest VtsHalBiometricsFaceTargetTest
Test: atest VtsHalBiometricsFingerprintTargetTest
Test: atest android.hardware.biometrics.face.FakeFaceEngineTest
Test: atest android.hardware.biometrics.face.FakeFingerprintEngineTest
Test: See README.md
Test: Verified that face and fingerprint get reset upon authenticating.

Change-Id: I57c1a61bec960e3be28736e6050be662ef412d8c
diff --git a/biometrics/face/aidl/default/FakeFaceEngine.cpp b/biometrics/face/aidl/default/FakeFaceEngine.cpp
new file mode 100644
index 0000000..0f088f4
--- /dev/null
+++ b/biometrics/face/aidl/default/FakeFaceEngine.cpp
@@ -0,0 +1,318 @@
+#include "FakeFaceEngine.h"
+
+#include <android-base/logging.h>
+
+#include <face.sysprop.h>
+
+#include "util/CancellationSignal.h"
+#include "util/Util.h"
+
+using namespace ::android::face::virt;
+
+namespace aidl::android::hardware::biometrics::face {
+
+FaceSensorType FakeFaceEngine::GetSensorType() {
+    std::string type = FaceHalProperties::type().value_or("");
+    if (type == "IR") {
+        return FaceSensorType::IR;
+    } else {
+        FaceHalProperties::type("RGB");
+        return FaceSensorType::RGB;
+    }
+}
+
+common::SensorStrength FakeFaceEngine::GetSensorStrength() {
+    std::string strength = FaceHalProperties::strength().value_or("");
+    if (strength == "convenience") {
+        return common::SensorStrength::CONVENIENCE;
+    } else if (strength == "weak") {
+        return common::SensorStrength::WEAK;
+    } else {
+        FaceHalProperties::strength("strong");
+        return common::SensorStrength::STRONG;
+    }
+}
+
+void FakeFaceEngine::generateChallengeImpl(ISessionCallback* cb) {
+    BEGIN_OP(0);
+    std::uniform_int_distribution<int64_t> dist;
+    auto challenge = dist(mRandom);
+    FaceHalProperties::challenge(challenge);
+    cb->onChallengeGenerated(challenge);
+}
+
+void FakeFaceEngine::revokeChallengeImpl(ISessionCallback* cb, int64_t challenge) {
+    BEGIN_OP(0);
+    FaceHalProperties::challenge({});
+    cb->onChallengeRevoked(challenge);
+}
+void FakeFaceEngine::getEnrollmentConfigImpl(ISessionCallback* /*cb*/,
+                                             std::vector<EnrollmentStageConfig>* /*return_val*/) {}
+void FakeFaceEngine::enrollImpl(ISessionCallback* cb, const keymaster::HardwareAuthToken& hat,
+                                EnrollmentType /*enrollmentType*/,
+                                const std::vector<Feature>& /*features*/,
+                                const std::future<void>& cancel) {
+    BEGIN_OP(FaceHalProperties::operation_start_enroll_latency().value_or(0));
+    // format is "<id>,<bucket_id>:<delay>:<succeeds>,<bucket_id>:<delay>:<succeeds>...
+    auto nextEnroll = FaceHalProperties::next_enrollment().value_or("");
+    // Erase the next enrollment
+    FaceHalProperties::next_enrollment({});
+
+    AuthenticationFrame frame;
+    frame.data.acquiredInfo = AcquiredInfo::START;
+    frame.data.vendorCode = 0;
+    cb->onAuthenticationFrame(frame);
+
+    // Do proper HAT verification in the real implementation.
+    if (hat.mac.empty()) {
+        LOG(ERROR) << "Fail: hat";
+        cb->onError(Error::UNABLE_TO_PROCESS, 0 /* vendorError */);
+        return;
+    }
+
+    if (FaceHalProperties::operation_enroll_fails().value_or(false)) {
+        LOG(ERROR) << "Fail: operation_enroll_fails";
+        cb->onError(Error::VENDOR, 0 /* vendorError */);
+        return;
+    }
+
+    auto parts = Util::split(nextEnroll, ",");
+    if (parts.size() < 2) {
+        LOG(ERROR) << "Fail: invalid next_enrollment for : " << nextEnroll;
+        cb->onError(Error::VENDOR, 0 /* vendorError */);
+        return;
+    }
+
+    auto enrollmentId = std::stoi(parts[0]);
+    const int numBuckets = parts.size() - 1;
+    for (size_t i = 1; i < parts.size(); i++) {
+        auto enrollHit = Util::split(parts[i], ":");
+        if (enrollHit.size() != 3) {
+            LOG(ERROR) << "Error when unpacking enrollment hit: " << parts[i];
+            cb->onError(Error::VENDOR, 0 /* vendorError */);
+        }
+        std::string bucket = enrollHit[0];
+        std::string delay = enrollHit[1];
+        std::string succeeds = enrollHit[2];
+
+        SLEEP_MS(std::stoi(delay));
+
+        if (shouldCancel(cancel)) {
+            LOG(ERROR) << "Fail: cancel";
+            cb->onError(Error::CANCELED, 0 /* vendorCode */);
+            return;
+        }
+
+        if (!IS_TRUE(succeeds)) {  // end and failed
+            LOG(ERROR) << "Fail: requested by caller: " << parts[i];
+            cb->onError(Error::UNABLE_TO_PROCESS, 0 /* vendorCode */);
+            return;
+        }
+
+        EnrollmentFrame frame;
+
+        frame.data.acquiredInfo = AcquiredInfo::GOOD;
+        frame.data.vendorCode = 0;
+        cb->onEnrollmentFrame(frame);
+
+        frame.data.acquiredInfo = AcquiredInfo::VENDOR;
+        frame.data.vendorCode = std::stoi(bucket);
+        cb->onEnrollmentFrame(frame);
+
+        int remainingBuckets = numBuckets - i;
+        if (remainingBuckets > 0) {
+            cb->onEnrollmentProgress(enrollmentId, remainingBuckets);
+        }
+    }
+
+    auto enrollments = FaceHalProperties::enrollments();
+    enrollments.push_back(enrollmentId);
+    FaceHalProperties::enrollments(enrollments);
+    LOG(INFO) << "enrolled : " << enrollmentId;
+    cb->onEnrollmentProgress(enrollmentId, 0);
+}
+
+void FakeFaceEngine::authenticateImpl(ISessionCallback* cb, int64_t /*operationId*/,
+                                      const std::future<void>& cancel) {
+    BEGIN_OP(FaceHalProperties::operation_authenticate_latency().value_or(0));
+
+    // Signal to the framework that we have begun authenticating.
+    AuthenticationFrame frame;
+    frame.data.acquiredInfo = AcquiredInfo::START;
+    frame.data.vendorCode = 0;
+    cb->onAuthenticationFrame(frame);
+
+    // Also signal that we have opened the camera.
+    frame = {};
+    frame.data.acquiredInfo = AcquiredInfo::FIRST_FRAME_RECEIVED;
+    frame.data.vendorCode = 0;
+    cb->onAuthenticationFrame(frame);
+
+    auto now = Util::getSystemNanoTime();
+    int64_t duration = FaceHalProperties::operation_authenticate_duration().value_or(0);
+    if (duration > 0) {
+        do {
+            SLEEP_MS(5);
+        } while (!Util::hasElapsed(now, duration));
+    }
+
+    if (FaceHalProperties::operation_authenticate_fails().value_or(false)) {
+        LOG(ERROR) << "Fail: operation_authenticate_fails";
+        cb->onError(Error::VENDOR, 0 /* vendorError */);
+        return;
+    }
+
+    if (FaceHalProperties::lockout().value_or(false)) {
+        LOG(ERROR) << "Fail: lockout";
+        cb->onLockoutPermanent();
+        cb->onError(Error::HW_UNAVAILABLE, 0 /* vendorError */);
+        return;
+    }
+
+    if (shouldCancel(cancel)) {
+        LOG(ERROR) << "Fail: cancel";
+        cb->onError(Error::CANCELED, 0 /* vendorCode */);
+        return;
+    }
+
+    auto id = FaceHalProperties::enrollment_hit().value_or(0);
+    auto enrolls = FaceHalProperties::enrollments();
+    auto isEnrolled = std::find(enrolls.begin(), enrolls.end(), id) != enrolls.end();
+    if (id < 0 || !isEnrolled) {
+        LOG(ERROR) << (isEnrolled ? "invalid enrollment hit" : "Fail: not enrolled");
+        cb->onAuthenticationFailed();
+        cb->onError(Error::UNABLE_TO_PROCESS, 0 /* vendorError */);
+        return;
+    }
+
+    cb->onAuthenticationSucceeded(id, {} /* hat */);
+}
+
+void FakeFaceEngine::detectInteractionImpl(ISessionCallback* cb, const std::future<void>& cancel) {
+    BEGIN_OP(FaceHalProperties::operation_detect_interaction_latency().value_or(0));
+
+    if (FaceHalProperties::operation_detect_interaction_fails().value_or(false)) {
+        LOG(ERROR) << "Fail: operation_detect_interaction_fails";
+        cb->onError(Error::VENDOR, 0 /* vendorError */);
+        return;
+    }
+
+    if (shouldCancel(cancel)) {
+        LOG(ERROR) << "Fail: cancel";
+        cb->onError(Error::CANCELED, 0 /* vendorCode */);
+        return;
+    }
+
+    auto id = FaceHalProperties::enrollment_hit().value_or(0);
+    auto enrolls = FaceHalProperties::enrollments();
+    auto isEnrolled = std::find(enrolls.begin(), enrolls.end(), id) != enrolls.end();
+    if (id <= 0 || !isEnrolled) {
+        LOG(ERROR) << "Fail: not enrolled";
+        cb->onError(Error::UNABLE_TO_PROCESS, 0 /* vendorError */);
+        return;
+    }
+
+    cb->onInteractionDetected();
+}
+
+void FakeFaceEngine::enumerateEnrollmentsImpl(ISessionCallback* cb) {
+    BEGIN_OP(0);
+    std::vector<int32_t> enrollments;
+    for (const auto& enrollmentId : FaceHalProperties::enrollments()) {
+        if (enrollmentId) {
+            enrollments.push_back(*enrollmentId);
+        }
+    }
+    cb->onEnrollmentsEnumerated(enrollments);
+}
+
+void FakeFaceEngine::removeEnrollmentsImpl(ISessionCallback* cb,
+                                           const std::vector<int32_t>& enrollmentIds) {
+    BEGIN_OP(0);
+
+    std::vector<std::optional<int32_t>> newEnrollments;
+    for (const auto& enrollment : FaceHalProperties::enrollments()) {
+        auto id = enrollment.value_or(0);
+        if (std::find(enrollmentIds.begin(), enrollmentIds.end(), id) == enrollmentIds.end()) {
+            newEnrollments.emplace_back(id);
+        }
+    }
+    FaceHalProperties::enrollments(newEnrollments);
+    cb->onEnrollmentsRemoved(enrollmentIds);
+}
+
+void FakeFaceEngine::getFeaturesImpl(ISessionCallback* cb) {
+    BEGIN_OP(0);
+
+    if (FaceHalProperties::enrollments().empty()) {
+        cb->onError(Error::UNABLE_TO_PROCESS, 0 /* vendorCode */);
+        return;
+    }
+
+    std::vector<Feature> featuresToReturn = {};
+    for (const auto& feature : FaceHalProperties::features()) {
+        if (feature) {
+            featuresToReturn.push_back((Feature)(*feature));
+        }
+    }
+    cb->onFeaturesRetrieved(featuresToReturn);
+}
+
+void FakeFaceEngine::setFeatureImpl(ISessionCallback* cb, const keymaster::HardwareAuthToken& hat,
+                                    Feature feature, bool enabled) {
+    BEGIN_OP(0);
+
+    if (FaceHalProperties::enrollments().empty()) {
+        LOG(ERROR) << "Unable to set feature, enrollments are empty";
+        cb->onError(Error::UNABLE_TO_PROCESS, 0 /* vendorCode */);
+        return;
+    }
+
+    if (hat.mac.empty()) {
+        LOG(ERROR) << "Unable to set feature, invalid hat";
+        cb->onError(Error::UNABLE_TO_PROCESS, 0 /* vendorCode */);
+        return;
+    }
+
+    auto features = FaceHalProperties::features();
+
+    auto itr = std::find_if(features.begin(), features.end(), [feature](const auto& theFeature) {
+        return *theFeature == (int)feature;
+    });
+
+    if (!enabled && (itr != features.end())) {
+        features.erase(itr);
+    } else if (enabled && (itr == features.end())) {
+        features.push_back((int)feature);
+    }
+
+    FaceHalProperties::features(features);
+    cb->onFeatureSet(feature);
+}
+
+void FakeFaceEngine::getAuthenticatorIdImpl(ISessionCallback* cb) {
+    BEGIN_OP(0);
+    // If this is a weak HAL return 0 per the spec.
+    if (GetSensorStrength() != common::SensorStrength::STRONG) {
+        cb->onAuthenticatorIdRetrieved(0);
+    } else {
+        cb->onAuthenticatorIdRetrieved(FaceHalProperties::authenticator_id().value_or(0));
+    }
+}
+
+void FakeFaceEngine::invalidateAuthenticatorIdImpl(ISessionCallback* cb) {
+    BEGIN_OP(0);
+    int64_t authenticatorId = FaceHalProperties::authenticator_id().value_or(0);
+    int64_t newId = authenticatorId + 1;
+    FaceHalProperties::authenticator_id(newId);
+    cb->onAuthenticatorIdInvalidated(newId);
+}
+
+void FakeFaceEngine::resetLockoutImpl(ISessionCallback* cb,
+                                      const keymaster::HardwareAuthToken& /*hat*/) {
+    BEGIN_OP(0);
+    FaceHalProperties::lockout(false);
+    cb->onLockoutCleared();
+}
+
+}  // namespace aidl::android::hardware::biometrics::face
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