diff --git a/keystore2/test_utils/authorizations.rs b/keystore2/test_utils/authorizations.rs
index b73aab5..f50eca6 100644
--- a/keystore2/test_utils/authorizations.rs
+++ b/keystore2/test_utils/authorizations.rs
@@ -305,6 +305,15 @@
         });
         self
     }
+
+    /// Set creation date-time.
+    pub fn creation_date_time(mut self, date: i64) -> Self {
+        self.0.push(KeyParameter {
+            tag: Tag::CREATION_DATETIME,
+            value: KeyParameterValue::DateTime(date),
+        });
+        self
+    }
 }
 
 impl Deref for AuthSetBuilder {
diff --git a/keystore2/test_utils/key_generations.rs b/keystore2/test_utils/key_generations.rs
index ccf27bc..0ffc32a 100644
--- a/keystore2/test_utils/key_generations.rs
+++ b/keystore2/test_utils/key_generations.rs
@@ -26,7 +26,7 @@
     Algorithm::Algorithm, BlockMode::BlockMode, Digest::Digest, EcCurve::EcCurve,
     ErrorCode::ErrorCode, HardwareAuthenticatorType::HardwareAuthenticatorType,
     KeyOrigin::KeyOrigin, KeyParameter::KeyParameter, KeyParameterValue::KeyParameterValue,
-    KeyPurpose::KeyPurpose, PaddingMode::PaddingMode, Tag::Tag,
+    KeyPurpose::KeyPurpose, PaddingMode::PaddingMode, SecurityLevel::SecurityLevel, Tag::Tag,
 };
 use android_system_keystore2::aidl::android::system::keystore2::{
     AuthenticatorSpec::AuthenticatorSpec, Authorization::Authorization,
@@ -38,7 +38,10 @@
 use crate::authorizations::AuthSetBuilder;
 use android_system_keystore2::binder::{ExceptionCode, Result as BinderResult};
 
-use crate::ffi_test_utils::{get_os_patchlevel, get_os_version, get_vendor_patchlevel};
+use crate::ffi_test_utils::{
+    get_os_patchlevel, get_os_version, get_value_from_attest_record, get_vendor_patchlevel,
+    validate_certchain,
+};
 
 /// Shell namespace.
 pub const SELINUX_SHELL_NAMESPACE: i64 = 1;
@@ -388,6 +391,12 @@
     })
 }
 
+/// Indicate whether the default device is KeyMint (rather than Keymaster).
+pub fn has_default_keymint() -> bool {
+    binder::is_declared("android.hardware.security.keymint.IKeyMintDevice/default")
+        .expect("Could not check for declared keymint interface")
+}
+
 /// Verify that given key param is listed in given authorizations list.
 pub fn check_key_param(authorizations: &[Authorization], key_param: &KeyParameter) -> bool {
     authorizations.iter().any(|auth| &auth.keyParameter == key_param)
@@ -468,6 +477,13 @@
             )
         }
     ));
+
+    if has_default_keymint() {
+        assert!(authorizations
+            .iter()
+            .map(|auth| &auth.keyParameter)
+            .any(|key_param| key_param.tag == Tag::CREATION_DATETIME));
+    }
 }
 
 /// Get the key `Authorization` for the given auth `Tag`.
@@ -1400,6 +1416,32 @@
         assert!(key_metadata.certificate.is_some());
         if gen_params.iter().any(|kp| kp.tag == Tag::ATTESTATION_CHALLENGE) {
             assert!(key_metadata.certificateChain.is_some());
+            let mut cert_chain: Vec<u8> = Vec::new();
+            cert_chain.extend(key_metadata.certificate.as_ref().unwrap());
+            cert_chain.extend(key_metadata.certificateChain.as_ref().unwrap());
+            validate_certchain(&cert_chain).expect("Error while validating cert chain");
+        }
+
+        if let Some(challenge_param) =
+            gen_params.iter().find(|kp| kp.tag == Tag::ATTESTATION_CHALLENGE)
+        {
+            if let KeyParameterValue::Blob(val) = &challenge_param.value {
+                let att_challenge = get_value_from_attest_record(
+                    key_metadata.certificate.as_ref().unwrap(),
+                    challenge_param.tag,
+                    key_metadata.keySecurityLevel,
+                )
+                .expect("Attestation challenge verification failed.");
+                assert_eq!(&att_challenge, val);
+            }
+
+            let att_app_id = get_value_from_attest_record(
+                key_metadata.certificate.as_ref().unwrap(),
+                Tag::ATTESTATION_APPLICATION_ID,
+                SecurityLevel::KEYSTORE,
+            )
+            .expect("Attestation application id verification failed.");
+            assert!(!att_app_id.is_empty());
         }
     }
     check_key_authorizations(&key_metadata.authorizations, gen_params, KeyOrigin::GENERATED);