diff --git a/security/keymint/aidl/vts/functional/AuthTest.cpp b/security/keymint/aidl/vts/functional/AuthTest.cpp
index 78c88f4..290e8fc 100644
--- a/security/keymint/aidl/vts/functional/AuthTest.cpp
+++ b/security/keymint/aidl/vts/functional/AuthTest.cpp
@@ -93,17 +93,21 @@
     void TearDown() {
         if (gk_ == nullptr) return;
         gk_->deleteUser(uid_);
+        if (alt_uid_ != 0) {
+            gk_->deleteUser(alt_uid_);
+        }
     }
 
     bool GatekeeperAvailable() { return (gk_ != nullptr) || (hidl_gk_ != nullptr); }
 
-    std::optional<GatekeeperEnrollResponse> doEnroll(const std::vector<uint8_t>& newPwd,
+    std::optional<GatekeeperEnrollResponse> doEnroll(uint32_t uid,
+                                                     const std::vector<uint8_t>& newPwd,
                                                      const std::vector<uint8_t>& curHandle = {},
                                                      const std::vector<uint8_t>& curPwd = {}) {
         if (gk_ != nullptr) {
             while (true) {
                 GatekeeperEnrollResponse rsp;
-                Status status = gk_->enroll(uid_, curHandle, curPwd, newPwd, &rsp);
+                Status status = gk_->enroll(uid, curHandle, curPwd, newPwd, &rsp);
                 if (!status.isOk() && status.getExceptionCode() == EX_SERVICE_SPECIFIC &&
                     status.getServiceSpecificError() == IGatekeeper::ERROR_RETRY_TIMEOUT) {
                     sleep(1);
@@ -120,7 +124,7 @@
             while (true) {
                 HidlGatekeeperResponse rsp;
                 auto status = hidl_gk_->enroll(
-                        uid_, curHandle, curPwd, newPwd,
+                        uid, curHandle, curPwd, newPwd,
                         [&rsp](const HidlGatekeeperResponse& cbRsp) { rsp = cbRsp; });
                 if (!status.isOk()) {
                     GTEST_LOG_(ERROR) << "doEnroll(HIDL) failed";
@@ -155,20 +159,23 @@
         }
     }
 
-    std::optional<GatekeeperEnrollResponse> doEnroll(const string& newPwd,
+    std::optional<GatekeeperEnrollResponse> doEnroll(uint32_t uid, const string& newPwd,
                                                      const std::vector<uint8_t>& curHandle = {},
                                                      const string& curPwd = {}) {
-        return doEnroll(std::vector<uint8_t>(newPwd.begin(), newPwd.end()), curHandle,
+        return doEnroll(uid, std::vector<uint8_t>(newPwd.begin(), newPwd.end()), curHandle,
                         std::vector<uint8_t>(curPwd.begin(), curPwd.end()));
     }
+    std::optional<GatekeeperEnrollResponse> doEnroll(const string& newPwd) {
+        return doEnroll(uid_, newPwd);
+    }
 
-    std::optional<HardwareAuthToken> doVerify(uint64_t challenge,
+    std::optional<HardwareAuthToken> doVerify(uint32_t uid, uint64_t challenge,
                                               const std::vector<uint8_t>& handle,
                                               const std::vector<uint8_t>& pwd) {
         if (gk_ != nullptr) {
             while (true) {
                 GatekeeperVerifyResponse rsp;
-                Status status = gk_->verify(uid_, challenge, handle, pwd, &rsp);
+                Status status = gk_->verify(uid, challenge, handle, pwd, &rsp);
                 if (!status.isOk() && status.getExceptionCode() == EX_SERVICE_SPECIFIC &&
                     status.getServiceSpecificError() == IGatekeeper::ERROR_RETRY_TIMEOUT) {
                     sleep(1);
@@ -185,7 +192,7 @@
             while (true) {
                 HidlGatekeeperResponse rsp;
                 auto status = hidl_gk_->verify(
-                        uid_, challenge, handle, pwd,
+                        uid, challenge, handle, pwd,
                         [&rsp](const HidlGatekeeperResponse& cbRsp) { rsp = cbRsp; });
                 if (!status.isOk()) {
                     GTEST_LOG_(ERROR) << "doVerify(HIDL) failed";
@@ -220,10 +227,15 @@
             return std::nullopt;
         }
     }
+    std::optional<HardwareAuthToken> doVerify(uint32_t uid, uint64_t challenge,
+                                              const std::vector<uint8_t>& handle,
+                                              const string& pwd) {
+        return doVerify(uid, challenge, handle, std::vector<uint8_t>(pwd.begin(), pwd.end()));
+    }
     std::optional<HardwareAuthToken> doVerify(uint64_t challenge,
                                               const std::vector<uint8_t>& handle,
                                               const string& pwd) {
-        return doVerify(challenge, handle, std::vector<uint8_t>(pwd.begin(), pwd.end()));
+        return doVerify(uid_, challenge, handle, pwd);
     }
 
     // Variants of the base class methods but with authentication information included.
@@ -268,6 +280,13 @@
         return plaintext;
     }
 
+    string SignMessage(const vector<uint8_t>& key_blob, const string& message,
+                       const AuthorizationSet& in_params, AuthorizationSet* out_params,
+                       const HardwareAuthToken& hat) {
+        SCOPED_TRACE("SignMessage");
+        return ProcessMessage(key_blob, KeyPurpose::SIGN, message, in_params, out_params, hat);
+    }
+
   protected:
     std::shared_ptr<IGatekeeper> gk_;
     sp<IHidlGatekeeper> hidl_gk_;
@@ -275,6 +294,8 @@
     string password_;
     uint32_t uid_;
     int64_t sid_;
+    uint32_t alt_uid_;
+    int64_t alt_sid_;
     std::vector<uint8_t> handle_;
 };
 
@@ -347,6 +368,116 @@
     }
 }
 
+// Test use of a key that requires user-authentication within recent history, but where
+// the `TimestampToken` provided to the device is unrelated to the in-progress operation.
+TEST_P(AuthTest, TimeoutAuthenticationIncorrectTimestampToken) {
+    if (!GatekeeperAvailable()) {
+        GTEST_SKIP() << "No Gatekeeper available";
+    }
+    if (!timestamp_token_required_) {
+        GTEST_SKIP() << "Test only applies to devices with no secure clock";
+    }
+    if (clock_ == nullptr) {
+        GTEST_SKIP() << "Device requires timestamps and no ISecureClock available";
+    }
+
+    // Create an AES key that requires authentication within the last 3 seconds.
+    const uint32_t timeout_secs = 3;
+    auto builder = AuthorizationSetBuilder()
+                           .AesEncryptionKey(256)
+                           .BlockMode(BlockMode::ECB)
+                           .Padding(PaddingMode::PKCS7)
+                           .Authorization(TAG_USER_SECURE_ID, sid_)
+                           .Authorization(TAG_USER_AUTH_TYPE, HardwareAuthenticatorType::PASSWORD)
+                           .Authorization(TAG_AUTH_TIMEOUT, timeout_secs);
+    vector<uint8_t> keyblob;
+    vector<KeyCharacteristics> key_characteristics;
+    vector<Certificate> cert_chain;
+    ASSERT_EQ(ErrorCode::OK,
+              GenerateKey(builder, std::nullopt, &keyblob, &key_characteristics, &cert_chain));
+
+    // Verify to get a HAT, arbitrary challenge.
+    const uint64_t challenge = 42;
+    const std::optional<HardwareAuthToken> hat = doVerify(challenge, handle_, password_);
+    ASSERT_TRUE(hat.has_value());
+    EXPECT_EQ(hat->userId, sid_);
+
+    // KeyMint implementation has no clock, so only detects timeout via timestamp token provided
+    // on update()/finish().  However, for this test we ensure that that the timestamp token has a
+    // *different* challenge value.
+    const string message = "Hello World!";
+    auto params = AuthorizationSetBuilder().BlockMode(BlockMode::ECB).Padding(PaddingMode::PKCS7);
+    AuthorizationSet out_params;
+    ASSERT_EQ(ErrorCode::OK, Begin(KeyPurpose::ENCRYPT, keyblob, params, &out_params, hat));
+
+    secureclock::TimeStampToken time_token;
+    EXPECT_EQ(ErrorCode::OK,
+              GetReturnErrorCode(clock_->generateTimeStamp(challenge_ + 1, &time_token)));
+    string output;
+    EXPECT_EQ(ErrorCode::KEY_USER_NOT_AUTHENTICATED,
+              Finish(message, {} /* signature */, &output, hat, time_token));
+}
+
+// Test use of a key with multiple USER_SECURE_ID values.  For variety, use an EC signing key
+// generated with attestation.
+TEST_P(AuthTest, TimeoutAuthenticationMultiSid) {
+    if (!GatekeeperAvailable()) {
+        GTEST_SKIP() << "No Gatekeeper available";
+    }
+    if (timestamp_token_required_ && clock_ == nullptr) {
+        GTEST_SKIP() << "Device requires timestamps and no ISecureClock available";
+    }
+
+    // Enroll a password for a second user.
+    alt_uid_ = 20001;
+    const string alt_password = "correcthorsebatterystaple2";
+    std::optional<GatekeeperEnrollResponse> rsp = doEnroll(alt_uid_, alt_password);
+    ASSERT_TRUE(rsp.has_value());
+    alt_sid_ = rsp->secureUserId;
+    const std::vector<uint8_t> alt_handle = rsp->data;
+
+    // Create an attested EC key that requires authentication within the last 3 seconds from either
+    // secure ID. Also allow any authenticator type.
+    const uint32_t timeout_secs = 3;
+    auto builder = AuthorizationSetBuilder()
+                           .EcdsaSigningKey(EcCurve::P_256)
+                           .Digest(Digest::NONE)
+                           .Digest(Digest::SHA_2_256)
+                           .SetDefaultValidity()
+                           .AttestationChallenge("challenge")
+                           .AttestationApplicationId("app_id")
+                           .Authorization(TAG_USER_SECURE_ID, alt_sid_)
+                           .Authorization(TAG_USER_SECURE_ID, sid_)
+                           .Authorization(TAG_USER_AUTH_TYPE, HardwareAuthenticatorType::ANY)
+                           .Authorization(TAG_AUTH_TIMEOUT, timeout_secs);
+    vector<uint8_t> keyblob;
+    vector<KeyCharacteristics> key_characteristics;
+    vector<Certificate> cert_chain;
+    ASSERT_EQ(ErrorCode::OK,
+              GenerateKey(builder, std::nullopt, &keyblob, &key_characteristics, &cert_chain));
+
+    // Verify first user to get a HAT that should work.
+    const uint64_t challenge = 42;
+    const std::optional<HardwareAuthToken> hat = doVerify(uid_, challenge, handle_, password_);
+    ASSERT_TRUE(hat.has_value());
+    EXPECT_EQ(hat->userId, sid_);
+
+    const string message = "Hello World!";
+    auto params = AuthorizationSetBuilder().Digest(Digest::SHA_2_256);
+    AuthorizationSet out_params;
+    const string signature = SignMessage(keyblob, message, params, &out_params, hat.value());
+
+    // Verify second user to get a HAT that should work.
+    const uint64_t alt_challenge = 43;
+    const std::optional<HardwareAuthToken> alt_hat =
+            doVerify(alt_uid_, alt_challenge, alt_handle, alt_password);
+    ASSERT_TRUE(alt_hat.has_value());
+    EXPECT_EQ(alt_hat->userId, alt_sid_);
+
+    const string alt_signature =
+            SignMessage(keyblob, message, params, &out_params, alt_hat.value());
+}
+
 // Test use of a key that requires an auth token for each action on the operation, with
 // a per-operation challenge value included.
 TEST_P(AuthTest, AuthPerOperation) {
@@ -407,6 +538,93 @@
               Finish(message, {} /* signature */, &ciphertext, hat.value()));
 }
 
+// Test use of a key that requires an auth token for each action on the operation, with
+// a per-operation challenge value included, with multiple secure IDs allowed.
+TEST_P(AuthTest, AuthPerOperationMultiSid) {
+    if (!GatekeeperAvailable()) {
+        GTEST_SKIP() << "No Gatekeeper available";
+    }
+
+    // Enroll a password for a second user.
+    alt_uid_ = 20001;
+    const string alt_password = "correcthorsebatterystaple2";
+    std::optional<GatekeeperEnrollResponse> rsp = doEnroll(alt_uid_, alt_password);
+    ASSERT_TRUE(rsp.has_value());
+    alt_sid_ = rsp->secureUserId;
+    const std::vector<uint8_t> alt_handle = rsp->data;
+
+    // Create an AES key that requires authentication per-action.
+    auto builder = AuthorizationSetBuilder()
+                           .AesEncryptionKey(256)
+                           .BlockMode(BlockMode::ECB)
+                           .Padding(PaddingMode::PKCS7)
+                           .Authorization(TAG_USER_SECURE_ID, sid_)
+                           .Authorization(TAG_USER_SECURE_ID, alt_sid_)
+                           .Authorization(TAG_USER_AUTH_TYPE, HardwareAuthenticatorType::ANY);
+    vector<uint8_t> keyblob;
+    vector<KeyCharacteristics> key_characteristics;
+    vector<Certificate> cert_chain;
+    ASSERT_EQ(ErrorCode::OK,
+              GenerateKey(builder, std::nullopt, &keyblob, &key_characteristics, &cert_chain));
+
+    // Get a HAT for first user with the challenge from an in-progress operation.
+    const string message = "Hello World!";
+    auto params = AuthorizationSetBuilder().BlockMode(BlockMode::ECB).Padding(PaddingMode::PKCS7);
+    AuthorizationSet out_params;
+    EXPECT_EQ(ErrorCode::OK, Begin(KeyPurpose::ENCRYPT, keyblob, params, &out_params));
+    const std::optional<HardwareAuthToken> hat = doVerify(uid_, challenge_, handle_, password_);
+    ASSERT_TRUE(hat.has_value());
+    EXPECT_EQ(hat->userId, sid_);
+    string ciphertext;
+    EXPECT_EQ(ErrorCode::OK, Finish(message, {} /* signature */, &ciphertext, hat.value()));
+
+    // Get a HAT for second user with the challenge from an in-progress operation.
+    EXPECT_EQ(ErrorCode::OK, Begin(KeyPurpose::ENCRYPT, keyblob, params, &out_params));
+    const std::optional<HardwareAuthToken> alt_hat =
+            doVerify(alt_uid_, challenge_, alt_handle, alt_password);
+    ASSERT_TRUE(alt_hat.has_value());
+    EXPECT_EQ(alt_hat->userId, alt_sid_);
+    string alt_ciphertext;
+    EXPECT_EQ(ErrorCode::OK, Finish(message, {} /* signature */, &ciphertext, alt_hat.value()));
+}
+
+// Test use of a key that requires an auth token for each action on the operation, but
+// which gets passed a HAT of the wrong type
+TEST_P(AuthTest, AuthPerOperationWrongAuthType) {
+    if (!GatekeeperAvailable()) {
+        GTEST_SKIP() << "No Gatekeeper available";
+    }
+
+    // Create an AES key that requires authentication per-action, but with no valid authenticator
+    // types.
+    auto builder =
+            AuthorizationSetBuilder()
+                    .AesEncryptionKey(256)
+                    .BlockMode(BlockMode::ECB)
+                    .Padding(PaddingMode::PKCS7)
+                    .Authorization(TAG_USER_SECURE_ID, sid_)
+                    .Authorization(TAG_USER_AUTH_TYPE, HardwareAuthenticatorType::FINGERPRINT);
+    vector<uint8_t> keyblob;
+    vector<KeyCharacteristics> key_characteristics;
+    vector<Certificate> cert_chain;
+    ASSERT_EQ(ErrorCode::OK,
+              GenerateKey(builder, std::nullopt, &keyblob, &key_characteristics, &cert_chain));
+
+    // Get a HAT with the challenge from an in-progress operation.
+    const string message = "Hello World!";
+    auto params = AuthorizationSetBuilder().BlockMode(BlockMode::ECB).Padding(PaddingMode::PKCS7);
+    AuthorizationSet out_params;
+    EXPECT_EQ(ErrorCode::OK, Begin(KeyPurpose::ENCRYPT, keyblob, params, &out_params));
+    const std::optional<HardwareAuthToken> hat = doVerify(challenge_, handle_, password_);
+    ASSERT_TRUE(hat.has_value());
+    EXPECT_EQ(hat->userId, sid_);
+
+    // Should fail because auth type doesn't (can't) match.
+    string ciphertext;
+    EXPECT_EQ(ErrorCode::KEY_USER_NOT_AUTHENTICATED,
+              Finish(message, {} /* signature */, &ciphertext, hat.value()));
+}
+
 INSTANTIATE_KEYMINT_AIDL_TEST(AuthTest);
 
 }  // namespace aidl::android::hardware::security::keymint::test