diff --git a/compatibility_matrices/compatibility_matrix.current.xml b/compatibility_matrices/compatibility_matrix.current.xml
index 91ca312..864ef66 100644
--- a/compatibility_matrices/compatibility_matrix.current.xml
+++ b/compatibility_matrices/compatibility_matrix.current.xml
@@ -287,7 +287,7 @@
     </hal>
     <hal format="aidl" optional="true">
         <name>android.hardware.identity</name>
-        <version>1-2</version>
+        <version>1-3</version>
         <interface>
             <name>IIdentityCredentialStore</name>
             <instance>default</instance>
diff --git a/identity/aidl/aidl_api/android.hardware.identity/current/android/hardware/identity/Certificate.aidl b/identity/aidl/aidl_api/android.hardware.identity/current/android/hardware/identity/Certificate.aidl
index 7e3002d..d8a8128 100644
--- a/identity/aidl/aidl_api/android.hardware.identity/current/android/hardware/identity/Certificate.aidl
+++ b/identity/aidl/aidl_api/android.hardware.identity/current/android/hardware/identity/Certificate.aidl
@@ -1,14 +1,29 @@
-///////////////////////////////////////////////////////////////////////////////
+/*
+ * Copyright 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *////////////////////////////////////////////////////////////////////////////////
 // THIS FILE IS IMMUTABLE. DO NOT EDIT IN ANY CASE.                          //
 ///////////////////////////////////////////////////////////////////////////////
 
-// This file is a snapshot of an AIDL interface (or parcelable). Do not try to
-// edit this file. It looks like you are doing that because you have modified
-// an AIDL interface in a backward-incompatible way, e.g., deleting a function
-// from an interface or a field from a parcelable and it broke the build. That
-// breakage is intended.
+// This file is a snapshot of an AIDL file. Do not edit it manually. There are
+// two cases:
+// 1). this is a frozen version file - do not edit this in any case.
+// 2). this is a 'current' file. If you make a backwards compatible change to
+//     the interface (from the latest frozen version), the build system will
+//     prompt you to update this file with `m <name>-update-api`.
 //
-// You must not make a backward incompatible changes to the AIDL files built
+// You must not make a backward incompatible change to any AIDL file built
 // with the aidl_interface module type with versions property set. The module
 // type is used to build AIDL files in a way that they can be used across
 // independently updatable components of the system. If a device is shipped
diff --git a/identity/aidl/aidl_api/android.hardware.identity/current/android/hardware/identity/CipherSuite.aidl b/identity/aidl/aidl_api/android.hardware.identity/current/android/hardware/identity/CipherSuite.aidl
index 447203f..2685525 100644
--- a/identity/aidl/aidl_api/android.hardware.identity/current/android/hardware/identity/CipherSuite.aidl
+++ b/identity/aidl/aidl_api/android.hardware.identity/current/android/hardware/identity/CipherSuite.aidl
@@ -1,14 +1,29 @@
-///////////////////////////////////////////////////////////////////////////////
+/*
+ * Copyright 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *////////////////////////////////////////////////////////////////////////////////
 // THIS FILE IS IMMUTABLE. DO NOT EDIT IN ANY CASE.                          //
 ///////////////////////////////////////////////////////////////////////////////
 
-// This file is a snapshot of an AIDL interface (or parcelable). Do not try to
-// edit this file. It looks like you are doing that because you have modified
-// an AIDL interface in a backward-incompatible way, e.g., deleting a function
-// from an interface or a field from a parcelable and it broke the build. That
-// breakage is intended.
+// This file is a snapshot of an AIDL file. Do not edit it manually. There are
+// two cases:
+// 1). this is a frozen version file - do not edit this in any case.
+// 2). this is a 'current' file. If you make a backwards compatible change to
+//     the interface (from the latest frozen version), the build system will
+//     prompt you to update this file with `m <name>-update-api`.
 //
-// You must not make a backward incompatible changes to the AIDL files built
+// You must not make a backward incompatible change to any AIDL file built
 // with the aidl_interface module type with versions property set. The module
 // type is used to build AIDL files in a way that they can be used across
 // independently updatable components of the system. If a device is shipped
diff --git a/identity/aidl/aidl_api/android.hardware.identity/current/android/hardware/identity/HardwareInformation.aidl b/identity/aidl/aidl_api/android.hardware.identity/current/android/hardware/identity/HardwareInformation.aidl
index e1296e0..f8d5a9e 100644
--- a/identity/aidl/aidl_api/android.hardware.identity/current/android/hardware/identity/HardwareInformation.aidl
+++ b/identity/aidl/aidl_api/android.hardware.identity/current/android/hardware/identity/HardwareInformation.aidl
@@ -1,14 +1,29 @@
-///////////////////////////////////////////////////////////////////////////////
+/*
+ * Copyright 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *////////////////////////////////////////////////////////////////////////////////
 // THIS FILE IS IMMUTABLE. DO NOT EDIT IN ANY CASE.                          //
 ///////////////////////////////////////////////////////////////////////////////
 
-// This file is a snapshot of an AIDL interface (or parcelable). Do not try to
-// edit this file. It looks like you are doing that because you have modified
-// an AIDL interface in a backward-incompatible way, e.g., deleting a function
-// from an interface or a field from a parcelable and it broke the build. That
-// breakage is intended.
+// This file is a snapshot of an AIDL file. Do not edit it manually. There are
+// two cases:
+// 1). this is a frozen version file - do not edit this in any case.
+// 2). this is a 'current' file. If you make a backwards compatible change to
+//     the interface (from the latest frozen version), the build system will
+//     prompt you to update this file with `m <name>-update-api`.
 //
-// You must not make a backward incompatible changes to the AIDL files built
+// You must not make a backward incompatible change to any AIDL file built
 // with the aidl_interface module type with versions property set. The module
 // type is used to build AIDL files in a way that they can be used across
 // independently updatable components of the system. If a device is shipped
diff --git a/identity/aidl/aidl_api/android.hardware.identity/current/android/hardware/identity/IIdentityCredential.aidl b/identity/aidl/aidl_api/android.hardware.identity/current/android/hardware/identity/IIdentityCredential.aidl
index 88104d9..a097895 100644
--- a/identity/aidl/aidl_api/android.hardware.identity/current/android/hardware/identity/IIdentityCredential.aidl
+++ b/identity/aidl/aidl_api/android.hardware.identity/current/android/hardware/identity/IIdentityCredential.aidl
@@ -1,14 +1,29 @@
-///////////////////////////////////////////////////////////////////////////////
+/*
+ * Copyright 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *////////////////////////////////////////////////////////////////////////////////
 // THIS FILE IS IMMUTABLE. DO NOT EDIT IN ANY CASE.                          //
 ///////////////////////////////////////////////////////////////////////////////
 
-// This file is a snapshot of an AIDL interface (or parcelable). Do not try to
-// edit this file. It looks like you are doing that because you have modified
-// an AIDL interface in a backward-incompatible way, e.g., deleting a function
-// from an interface or a field from a parcelable and it broke the build. That
-// breakage is intended.
+// This file is a snapshot of an AIDL file. Do not edit it manually. There are
+// two cases:
+// 1). this is a frozen version file - do not edit this in any case.
+// 2). this is a 'current' file. If you make a backwards compatible change to
+//     the interface (from the latest frozen version), the build system will
+//     prompt you to update this file with `m <name>-update-api`.
 //
-// You must not make a backward incompatible changes to the AIDL files built
+// You must not make a backward incompatible change to any AIDL file built
 // with the aidl_interface module type with versions property set. The module
 // type is used to build AIDL files in a way that they can be used across
 // independently updatable components of the system. If a device is shipped
@@ -18,6 +33,9 @@
 package android.hardware.identity;
 @VintfStability
 interface IIdentityCredential {
+  /**
+   * @deprecated use deleteCredentalWithChallenge() instead.
+   */
   byte[] deleteCredential();
   byte[] createEphemeralKeyPair();
   void setReaderEphemeralPublicKey(in byte[] publicKey);
@@ -29,4 +47,7 @@
   android.hardware.identity.Certificate generateSigningKeyPair(out byte[] signingKeyBlob);
   void setRequestedNamespaces(in android.hardware.identity.RequestNamespace[] requestNamespaces);
   void setVerificationToken(in android.hardware.keymaster.VerificationToken verificationToken);
+  byte[] deleteCredentialWithChallenge(in byte[] challenge);
+  byte[] proveOwnership(in byte[] challenge);
+  android.hardware.identity.IWritableIdentityCredential updateCredential();
 }
diff --git a/identity/aidl/aidl_api/android.hardware.identity/current/android/hardware/identity/IIdentityCredentialStore.aidl b/identity/aidl/aidl_api/android.hardware.identity/current/android/hardware/identity/IIdentityCredentialStore.aidl
index 5dafb76..c6fb3c8 100644
--- a/identity/aidl/aidl_api/android.hardware.identity/current/android/hardware/identity/IIdentityCredentialStore.aidl
+++ b/identity/aidl/aidl_api/android.hardware.identity/current/android/hardware/identity/IIdentityCredentialStore.aidl
@@ -1,14 +1,29 @@
-///////////////////////////////////////////////////////////////////////////////
+/*
+ * Copyright 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *////////////////////////////////////////////////////////////////////////////////
 // THIS FILE IS IMMUTABLE. DO NOT EDIT IN ANY CASE.                          //
 ///////////////////////////////////////////////////////////////////////////////
 
-// This file is a snapshot of an AIDL interface (or parcelable). Do not try to
-// edit this file. It looks like you are doing that because you have modified
-// an AIDL interface in a backward-incompatible way, e.g., deleting a function
-// from an interface or a field from a parcelable and it broke the build. That
-// breakage is intended.
+// This file is a snapshot of an AIDL file. Do not edit it manually. There are
+// two cases:
+// 1). this is a frozen version file - do not edit this in any case.
+// 2). this is a 'current' file. If you make a backwards compatible change to
+//     the interface (from the latest frozen version), the build system will
+//     prompt you to update this file with `m <name>-update-api`.
 //
-// You must not make a backward incompatible changes to the AIDL files built
+// You must not make a backward incompatible change to any AIDL file built
 // with the aidl_interface module type with versions property set. The module
 // type is used to build AIDL files in a way that they can be used across
 // independently updatable components of the system. If a device is shipped
diff --git a/identity/aidl/aidl_api/android.hardware.identity/current/android/hardware/identity/IWritableIdentityCredential.aidl b/identity/aidl/aidl_api/android.hardware.identity/current/android/hardware/identity/IWritableIdentityCredential.aidl
index c5ac9d6..a713462 100644
--- a/identity/aidl/aidl_api/android.hardware.identity/current/android/hardware/identity/IWritableIdentityCredential.aidl
+++ b/identity/aidl/aidl_api/android.hardware.identity/current/android/hardware/identity/IWritableIdentityCredential.aidl
@@ -1,14 +1,29 @@
-///////////////////////////////////////////////////////////////////////////////
+/*
+ * Copyright 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *////////////////////////////////////////////////////////////////////////////////
 // THIS FILE IS IMMUTABLE. DO NOT EDIT IN ANY CASE.                          //
 ///////////////////////////////////////////////////////////////////////////////
 
-// This file is a snapshot of an AIDL interface (or parcelable). Do not try to
-// edit this file. It looks like you are doing that because you have modified
-// an AIDL interface in a backward-incompatible way, e.g., deleting a function
-// from an interface or a field from a parcelable and it broke the build. That
-// breakage is intended.
+// This file is a snapshot of an AIDL file. Do not edit it manually. There are
+// two cases:
+// 1). this is a frozen version file - do not edit this in any case.
+// 2). this is a 'current' file. If you make a backwards compatible change to
+//     the interface (from the latest frozen version), the build system will
+//     prompt you to update this file with `m <name>-update-api`.
 //
-// You must not make a backward incompatible changes to the AIDL files built
+// You must not make a backward incompatible change to any AIDL file built
 // with the aidl_interface module type with versions property set. The module
 // type is used to build AIDL files in a way that they can be used across
 // independently updatable components of the system. If a device is shipped
diff --git a/identity/aidl/aidl_api/android.hardware.identity/current/android/hardware/identity/RequestDataItem.aidl b/identity/aidl/aidl_api/android.hardware.identity/current/android/hardware/identity/RequestDataItem.aidl
index 24ec26a..c9c2b9f 100644
--- a/identity/aidl/aidl_api/android.hardware.identity/current/android/hardware/identity/RequestDataItem.aidl
+++ b/identity/aidl/aidl_api/android.hardware.identity/current/android/hardware/identity/RequestDataItem.aidl
@@ -1,14 +1,29 @@
-///////////////////////////////////////////////////////////////////////////////
+/*
+ * Copyright 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *////////////////////////////////////////////////////////////////////////////////
 // THIS FILE IS IMMUTABLE. DO NOT EDIT IN ANY CASE.                          //
 ///////////////////////////////////////////////////////////////////////////////
 
-// This file is a snapshot of an AIDL interface (or parcelable). Do not try to
-// edit this file. It looks like you are doing that because you have modified
-// an AIDL interface in a backward-incompatible way, e.g., deleting a function
-// from an interface or a field from a parcelable and it broke the build. That
-// breakage is intended.
+// This file is a snapshot of an AIDL file. Do not edit it manually. There are
+// two cases:
+// 1). this is a frozen version file - do not edit this in any case.
+// 2). this is a 'current' file. If you make a backwards compatible change to
+//     the interface (from the latest frozen version), the build system will
+//     prompt you to update this file with `m <name>-update-api`.
 //
-// You must not make a backward incompatible changes to the AIDL files built
+// You must not make a backward incompatible change to any AIDL file built
 // with the aidl_interface module type with versions property set. The module
 // type is used to build AIDL files in a way that they can be used across
 // independently updatable components of the system. If a device is shipped
diff --git a/identity/aidl/aidl_api/android.hardware.identity/current/android/hardware/identity/RequestNamespace.aidl b/identity/aidl/aidl_api/android.hardware.identity/current/android/hardware/identity/RequestNamespace.aidl
index af00f3b..aaf1e20 100644
--- a/identity/aidl/aidl_api/android.hardware.identity/current/android/hardware/identity/RequestNamespace.aidl
+++ b/identity/aidl/aidl_api/android.hardware.identity/current/android/hardware/identity/RequestNamespace.aidl
@@ -1,14 +1,29 @@
-///////////////////////////////////////////////////////////////////////////////
+/*
+ * Copyright 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *////////////////////////////////////////////////////////////////////////////////
 // THIS FILE IS IMMUTABLE. DO NOT EDIT IN ANY CASE.                          //
 ///////////////////////////////////////////////////////////////////////////////
 
-// This file is a snapshot of an AIDL interface (or parcelable). Do not try to
-// edit this file. It looks like you are doing that because you have modified
-// an AIDL interface in a backward-incompatible way, e.g., deleting a function
-// from an interface or a field from a parcelable and it broke the build. That
-// breakage is intended.
+// This file is a snapshot of an AIDL file. Do not edit it manually. There are
+// two cases:
+// 1). this is a frozen version file - do not edit this in any case.
+// 2). this is a 'current' file. If you make a backwards compatible change to
+//     the interface (from the latest frozen version), the build system will
+//     prompt you to update this file with `m <name>-update-api`.
 //
-// You must not make a backward incompatible changes to the AIDL files built
+// You must not make a backward incompatible change to any AIDL file built
 // with the aidl_interface module type with versions property set. The module
 // type is used to build AIDL files in a way that they can be used across
 // independently updatable components of the system. If a device is shipped
diff --git a/identity/aidl/aidl_api/android.hardware.identity/current/android/hardware/identity/SecureAccessControlProfile.aidl b/identity/aidl/aidl_api/android.hardware.identity/current/android/hardware/identity/SecureAccessControlProfile.aidl
index dfc1ad0..695fb3f 100644
--- a/identity/aidl/aidl_api/android.hardware.identity/current/android/hardware/identity/SecureAccessControlProfile.aidl
+++ b/identity/aidl/aidl_api/android.hardware.identity/current/android/hardware/identity/SecureAccessControlProfile.aidl
@@ -1,14 +1,29 @@
-///////////////////////////////////////////////////////////////////////////////
+/*
+ * Copyright 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *////////////////////////////////////////////////////////////////////////////////
 // THIS FILE IS IMMUTABLE. DO NOT EDIT IN ANY CASE.                          //
 ///////////////////////////////////////////////////////////////////////////////
 
-// This file is a snapshot of an AIDL interface (or parcelable). Do not try to
-// edit this file. It looks like you are doing that because you have modified
-// an AIDL interface in a backward-incompatible way, e.g., deleting a function
-// from an interface or a field from a parcelable and it broke the build. That
-// breakage is intended.
+// This file is a snapshot of an AIDL file. Do not edit it manually. There are
+// two cases:
+// 1). this is a frozen version file - do not edit this in any case.
+// 2). this is a 'current' file. If you make a backwards compatible change to
+//     the interface (from the latest frozen version), the build system will
+//     prompt you to update this file with `m <name>-update-api`.
 //
-// You must not make a backward incompatible changes to the AIDL files built
+// You must not make a backward incompatible change to any AIDL file built
 // with the aidl_interface module type with versions property set. The module
 // type is used to build AIDL files in a way that they can be used across
 // independently updatable components of the system. If a device is shipped
diff --git a/identity/aidl/android/hardware/identity/IIdentityCredential.aidl b/identity/aidl/android/hardware/identity/IIdentityCredential.aidl
index 702334d..d23f88c 100644
--- a/identity/aidl/android/hardware/identity/IIdentityCredential.aidl
+++ b/identity/aidl/android/hardware/identity/IIdentityCredential.aidl
@@ -19,6 +19,7 @@
 import android.hardware.identity.Certificate;
 import android.hardware.identity.RequestNamespace;
 import android.hardware.identity.SecureAccessControlProfile;
+import android.hardware.identity.IWritableIdentityCredential;
 import android.hardware.keymaster.HardwareAuthToken;
 import android.hardware.keymaster.VerificationToken;
 
@@ -40,7 +41,11 @@
      * After this method has been called, the persistent storage used for credentialData should
      * be deleted.
      *
-     * @return a COSE_Sign1 signature described above.
+     * This method was deprecated in API version 3 because there's no challenge so freshness
+     * can't be checked. Use deleteCredentalWithChallenge() instead.
+     *
+     * @return a COSE_Sign1 signature described above
+     * @deprecated use deleteCredentalWithChallenge() instead.
      */
     byte[] deleteCredential();
 
@@ -353,6 +358,18 @@
      *
      *  - subjectPublicKeyInfo: must contain attested public key.
      *
+     * As of API version 3, the certificate shall also have an X.509 extension at
+     * OID 1.3.6.1.4.1.11129.2.1.26 which shall contain an OCTET STRING with the
+     * bytes of the CBOR with the following CDDL:
+     *
+     *   ProofOfBinding = [
+     *     "ProofOfBinding",
+     *     bstr,              // Contains SHA-256(ProofOfProvisioning)
+     *   ]
+     *
+     * This CBOR enables an issuer to determine the exact state of the credential it
+     * returns issuer-signed data for.
+     *
      * @param out signingKeyBlob contains an AES-GCM-ENC(storageKey, R, signingKey, docType)
      *     where signingKey is an EC private key in uncompressed form. That is, the returned
      *     blob is an encrypted copy of the newly-generated private signing key.
@@ -381,4 +398,63 @@
     *   The verification token. This token is only valid if the timestamp field is non-zero.
     */
     void setVerificationToken(in VerificationToken verificationToken);
+
+    /**
+     * Delete a credential.
+     *
+     * This method returns a COSE_Sign1 data structure signed by CredentialKey
+     * with payload set to the ProofOfDeletion CBOR below:
+     *
+     *     ProofOfDeletion = [
+     *          "ProofOfDeletion",            ; tstr
+     *          tstr,                         ; DocType
+     *          bstr,                         ; Challenge
+     *          bool                          ; true if this is a test credential, should
+     *                                        ; always be false.
+     *     ]
+     *
+     * After this method has been called, the persistent storage used for credentialData should
+     * be deleted.
+     *
+     * This method was introduced in API version 3.
+     *
+     * @param challenge a challenge set by the issuer to ensure freshness. Maximum size is 32 bytes
+     *     and it may be empty. Fails with STATUS_INVALID_DATA if bigger than 32 bytes.
+     * @return a COSE_Sign1 signature described above.
+     */
+    byte[] deleteCredentialWithChallenge(in byte[] challenge);
+
+    /**
+     * Prove ownership of credential.
+     *
+     * This method returns a COSE_Sign1 data structure signed by CredentialKey with payload
+     * set to the ProofOfOwnership CBOR below.
+     *
+     *     ProofOfOwnership = [
+     *          "ProofOfOwnership",           ; tstr
+     *          tstr,                         ; DocType
+     *          bstr,                         ; Challenge
+     *          bool                          ; true if this is a test credential, should
+     *                                        ; always be false.
+     *     ]
+     *
+     * This method was introduced in API version 3.
+     *
+     * @param challenge a challenge set by the issuer to ensure freshness. Maximum size is 32 bytes
+     *     and it may be empty. Fails with STATUS_INVALID_DATA if bigger than 32 bytes.
+     * @return a COSE_Sign1 signature described above.
+     */
+    byte[] proveOwnership(in byte[] challenge);
+
+    /**
+     * Called to start updating the credential with new data items.
+     *
+     * If the getAttestationCertificate() method is called on the returned object
+     * it fails with the error STATUS_FAILED.
+     *
+     * This method was introduced in API version 3.
+     *
+     * @return an IWritableIdentityCredential
+     */
+    IWritableIdentityCredential updateCredential();
 }
diff --git a/identity/aidl/android/hardware/identity/IIdentityCredentialStore.aidl b/identity/aidl/android/hardware/identity/IIdentityCredentialStore.aidl
index 33e25b1..638be79 100644
--- a/identity/aidl/android/hardware/identity/IIdentityCredentialStore.aidl
+++ b/identity/aidl/android/hardware/identity/IIdentityCredentialStore.aidl
@@ -104,6 +104,11 @@
  * All binder calls in the HAL may return a ServiceSpecificException with statuses from the
  * STATUS_* integers defined in this interface. Each method states which status can be returned
  * and under which circumstances.
+ *
+ * The API described here is API version 3 which corresponds to feature version 202101
+ * of the android.security.identity Framework API. An XML file declaring the feature
+ * android.hardware.identity_credential (or android.hardware.identity_credential.direct_access
+ * if implementing the Direct Access HAL) should be included declaring this feature version.
  */
 @VintfStability
 interface IIdentityCredentialStore {
@@ -230,6 +235,9 @@
      *     return argument of the same name in finishAddingEntries(), in
      *     IWritableIdentityCredential.
      *
+     *     Note that the format of credentialData may depend on the feature version.
+     *     Implementations must support credentialData created by an earlier feature version.
+     *
      * @return an IIdentityCredential interface that provides operations on the Credential.
      */
     IIdentityCredential getCredential(in CipherSuite cipherSuite, in byte[] credentialData);
diff --git a/identity/aidl/android/hardware/identity/IWritableIdentityCredential.aidl b/identity/aidl/android/hardware/identity/IWritableIdentityCredential.aidl
index c48cb66..5f878ee 100644
--- a/identity/aidl/android/hardware/identity/IWritableIdentityCredential.aidl
+++ b/identity/aidl/android/hardware/identity/IWritableIdentityCredential.aidl
@@ -263,7 +263,9 @@
      *
      *     where HBK is a unique hardware-bound key that has never existed outside of the secure
      *     environment (except it's all zeroes if testCredential is True) and CredentialKeys is
-     *     the CBOR-encoded structure (in CDDL notation):
+     *     the CBOR-encoded structure (in CDDL notation) given below.
+     *
+     *     In API versions 1 and 2 it was the following
      *
      *         CredentialKeys = [
      *              bstr,   ; storageKey, a 128-bit AES key
@@ -271,6 +273,17 @@
      *                      ; in uncompressed form
      *         ]
      *
+     *     In API version 3 or later it must be the following
+     *
+     *         CredentialKeys = [
+     *              bstr,   ; storageKey, a 128-bit AES key
+     *              bstr    ; credentialPrivKey, the private key for credentialKey
+     *                      ; in uncompressed form
+     *              bstr    ; SHA-256(ProofOfProvisioning)
+     *         ]
+     *
+     *     Additional elements may be added to the CredentialKeys array in future versions.
+     *
      * @param out proofOfProvisioningSignature proves to the IA that the credential was imported
      *     into the secure hardware without alteration or error.  When the final addEntry() call is
      *     made (when the number of provisioned entries equals the sum of the items in
@@ -321,4 +334,5 @@
      * @param expectedProofOfProvisioningSize the expected size of ProofOfProvisioning.
      */
     void setExpectedProofOfProvisioningSize(in int expectedProofOfProvisioningSize);
+
 }
diff --git a/identity/aidl/default/Android.bp b/identity/aidl/default/Android.bp
index 7f342d0..8744648 100644
--- a/identity/aidl/default/Android.bp
+++ b/identity/aidl/default/Android.bp
@@ -12,6 +12,7 @@
     cflags: [
         "-Wall",
         "-Wextra",
+        "-Wno-deprecated-declarations",
     ],
     shared_libs: [
         "liblog",
@@ -28,8 +29,8 @@
         "libsoft_attestation_cert",
         "libpuresoftkeymasterdevice",
         "android.hardware.identity-support-lib",
-        "android.hardware.identity-ndk_platform",
-        "android.hardware.keymaster-ndk_platform",
+        "android.hardware.identity-unstable-ndk_platform",
+        "android.hardware.keymaster-unstable-ndk_platform",
     ],
 }
 
@@ -88,8 +89,8 @@
         "libsoft_attestation_cert",
         "libpuresoftkeymasterdevice",
         "android.hardware.identity-support-lib",
-        "android.hardware.identity-ndk_platform",
-        "android.hardware.keymaster-ndk_platform",
+        "android.hardware.identity-unstable-ndk_platform",
+        "android.hardware.keymaster-unstable-ndk_platform",
         "android.hardware.identity-libeic-hal-common",
         "android.hardware.identity-libeic-library",
     ],
@@ -97,4 +98,14 @@
         "service.cpp",
         "FakeSecureHardwareProxy.cpp",
     ],
+    required: [
+        "android.hardware.identity_credential.xml",
+    ],
+}
+
+prebuilt_etc {
+    name: "android.hardware.identity_credential.xml",
+    sub_dir: "permissions",
+    vendor: true,
+    src: "android.hardware.identity_credential.xml",
 }
diff --git a/identity/aidl/default/EicOpsImpl.cc b/identity/aidl/default/EicOpsImpl.cc
index 3f2ec8b..8ec4cc9 100644
--- a/identity/aidl/default/EicOpsImpl.cc
+++ b/identity/aidl/default/EicOpsImpl.cc
@@ -45,6 +45,7 @@
 
 #include "EicOps.h"
 
+using ::std::map;
 using ::std::optional;
 using ::std::string;
 using ::std::tuple;
@@ -212,7 +213,8 @@
         return false;
     }
     if (privKey.value().size() != EIC_P256_PRIV_KEY_SIZE) {
-        eicDebug("Private key is not %zd bytes long as expected", (size_t)EIC_P256_PRIV_KEY_SIZE);
+        eicDebug("Private key is %zd bytes, expected %zd", privKey.value().size(),
+                 (size_t)EIC_P256_PRIV_KEY_SIZE);
         return false;
     }
 
@@ -224,7 +226,7 @@
     }
     // ecKeyPairGetPublicKey() returns 0x04 | x | y, we don't want the leading 0x04.
     if (pubKey.value().size() != EIC_P256_PUB_KEY_SIZE + 1) {
-        eicDebug("Private key is %zd bytes long, expected %zd", pubKey.value().size(),
+        eicDebug("Public key is %zd bytes long, expected %zd", pubKey.value().size(),
                  (size_t)EIC_P256_PRIV_KEY_SIZE + 1);
         return false;
     }
@@ -272,7 +274,8 @@
         return false;
     }
     if (privKey.value().size() != EIC_P256_PRIV_KEY_SIZE) {
-        eicDebug("Private key is not %zd bytes long as expected", (size_t)EIC_P256_PRIV_KEY_SIZE);
+        eicDebug("Private key is %zd bytes, expected %zd", privKey.value().size(),
+                 (size_t)EIC_P256_PRIV_KEY_SIZE);
         return false;
     }
 
@@ -284,8 +287,8 @@
 bool eicOpsSignEcKey(const uint8_t publicKey[EIC_P256_PUB_KEY_SIZE],
                      const uint8_t signingKey[EIC_P256_PRIV_KEY_SIZE], unsigned int serial,
                      const char* issuerName, const char* subjectName, time_t validityNotBefore,
-                     time_t validityNotAfter, uint8_t* cert,
-                     size_t* certSize) {  // inout
+                     time_t validityNotAfter, const uint8_t* proofOfBinding,
+                     size_t proofOfBindingSize, uint8_t* cert, size_t* certSize) {  // inout
     vector<uint8_t> signingKeyVec(EIC_P256_PRIV_KEY_SIZE);
     memcpy(signingKeyVec.data(), signingKey, EIC_P256_PRIV_KEY_SIZE);
 
@@ -293,12 +296,18 @@
     pubKeyVec[0] = 0x04;
     memcpy(pubKeyVec.data() + 1, publicKey, EIC_P256_PUB_KEY_SIZE);
 
-    std::string serialDecimal = android::base::StringPrintf("%d", serial);
+    string serialDecimal = android::base::StringPrintf("%d", serial);
+
+    map<string, vector<uint8_t>> extensions;
+    if (proofOfBinding != nullptr) {
+        vector<uint8_t> proofOfBindingVec(proofOfBinding, proofOfBinding + proofOfBindingSize);
+        extensions["1.3.6.1.4.1.11129.2.1.26"] = proofOfBindingVec;
+    }
 
     optional<vector<uint8_t>> certVec =
             android::hardware::identity::support::ecPublicKeyGenerateCertificate(
                     pubKeyVec, signingKeyVec, serialDecimal, issuerName, subjectName,
-                    validityNotBefore, validityNotAfter);
+                    validityNotBefore, validityNotAfter, extensions);
     if (!certVec) {
         eicDebug("Error generating certificate");
         return false;
diff --git a/identity/aidl/default/FakeSecureHardwareProxy.cpp b/identity/aidl/default/FakeSecureHardwareProxy.cpp
index de6762f..287ffb8 100644
--- a/identity/aidl/default/FakeSecureHardwareProxy.cpp
+++ b/identity/aidl/default/FakeSecureHardwareProxy.cpp
@@ -67,6 +67,13 @@
     return eicProvisioningInit(&ctx_, testCredential);
 }
 
+bool FakeSecureHardwareProvisioningProxy::initializeForUpdate(
+        bool testCredential, string docType, vector<uint8_t> encryptedCredentialKeys) {
+    return eicProvisioningInitForUpdate(&ctx_, testCredential, docType.c_str(),
+                                        encryptedCredentialKeys.data(),
+                                        encryptedCredentialKeys.size());
+}
+
 // Returns public key certificate.
 optional<vector<uint8_t>> FakeSecureHardwareProvisioningProxy::createCredentialKey(
         const vector<uint8_t>& challenge, const vector<uint8_t>& applicationId) {
@@ -140,14 +147,16 @@
     return signatureOfToBeSigned;
 }
 
-// Returns encryptedCredentialKeys (80 bytes).
+// Returns encryptedCredentialKeys.
 optional<vector<uint8_t>> FakeSecureHardwareProvisioningProxy::finishGetCredentialData(
         const string& docType) {
-    vector<uint8_t> encryptedCredentialKeys(80);
+    vector<uint8_t> encryptedCredentialKeys(116);
+    size_t size = encryptedCredentialKeys.size();
     if (!eicProvisioningFinishGetCredentialData(&ctx_, docType.c_str(),
-                                                encryptedCredentialKeys.data())) {
+                                                encryptedCredentialKeys.data(), &size)) {
         return {};
     }
+    encryptedCredentialKeys.resize(size);
     return encryptedCredentialKeys;
 }
 
@@ -162,7 +171,7 @@
     LOG(INFO) << "FakeSecureHardwarePresentationProxy created, sizeof(EicPresentation): "
               << sizeof(EicPresentation);
     return eicPresentationInit(&ctx_, testCredential, docType.c_str(),
-                               encryptedCredentialKeys.data());
+                               encryptedCredentialKeys.data(), encryptedCredentialKeys.size());
 }
 
 // Returns publicKeyCert (1st component) and signingKeyBlob (2nd component)
@@ -312,13 +321,27 @@
 }
 
 optional<vector<uint8_t>> FakeSecureHardwarePresentationProxy::deleteCredential(
-        const string& docType, size_t proofOfDeletionCborSize) {
+        const string& docType, const vector<uint8_t>& challenge, bool includeChallenge,
+        size_t proofOfDeletionCborSize) {
     vector<uint8_t> signatureOfToBeSigned(EIC_ECDSA_P256_SIGNATURE_SIZE);
-    if (!eicPresentationDeleteCredential(&ctx_, docType.c_str(), proofOfDeletionCborSize,
+    if (!eicPresentationDeleteCredential(&ctx_, docType.c_str(), challenge.data(), challenge.size(),
+                                         includeChallenge, proofOfDeletionCborSize,
                                          signatureOfToBeSigned.data())) {
         return {};
     }
     return signatureOfToBeSigned;
 }
 
+optional<vector<uint8_t>> FakeSecureHardwarePresentationProxy::proveOwnership(
+        const string& docType, bool testCredential, const vector<uint8_t>& challenge,
+        size_t proofOfOwnershipCborSize) {
+    vector<uint8_t> signatureOfToBeSigned(EIC_ECDSA_P256_SIGNATURE_SIZE);
+    if (!eicPresentationProveOwnership(&ctx_, docType.c_str(), testCredential, challenge.data(),
+                                       challenge.size(), proofOfOwnershipCborSize,
+                                       signatureOfToBeSigned.data())) {
+        return {};
+    }
+    return signatureOfToBeSigned;
+}
+
 }  // namespace android::hardware::identity
diff --git a/identity/aidl/default/FakeSecureHardwareProxy.h b/identity/aidl/default/FakeSecureHardwareProxy.h
index b858dd4..6852c1a 100644
--- a/identity/aidl/default/FakeSecureHardwareProxy.h
+++ b/identity/aidl/default/FakeSecureHardwareProxy.h
@@ -32,6 +32,9 @@
 
     bool initialize(bool testCredential) override;
 
+    bool initializeForUpdate(bool testCredential, string docType,
+                             vector<uint8_t> encryptedCredentialKeys) override;
+
     bool shutdown() override;
 
     // Returns public key certificate.
@@ -122,8 +125,14 @@
     optional<vector<uint8_t>> finishRetrieval() override;
 
     optional<vector<uint8_t>> deleteCredential(const string& docType,
+                                               const vector<uint8_t>& challenge,
+                                               bool includeChallenge,
                                                size_t proofOfDeletionCborSize) override;
 
+    optional<vector<uint8_t>> proveOwnership(const string& docType, bool testCredential,
+                                             const vector<uint8_t>& challenge,
+                                             size_t proofOfOwnershipCborSize) override;
+
     bool shutdown() override;
 
   protected:
diff --git a/identity/aidl/default/android.hardware.identity_credential.xml b/identity/aidl/default/android.hardware.identity_credential.xml
new file mode 100644
index 0000000..5149792
--- /dev/null
+++ b/identity/aidl/default/android.hardware.identity_credential.xml
@@ -0,0 +1,18 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright 2021 The Android Open Source Project
+
+     Licensed under the Apache License, Version 2.0 (the "License");
+     you may not use this file except in compliance with the License.
+     You may obtain a copy of the License at
+
+          http://www.apache.org/licenses/LICENSE-2.0
+
+     Unless required by applicable law or agreed to in writing, software
+     distributed under the License is distributed on an "AS IS" BASIS,
+     WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+     See the License for the specific language governing permissions and
+     limitations under the License.
+-->
+<permissions>
+  <feature name="android.hardware.identity_credential" version="202101" />
+</permissions>
diff --git a/identity/aidl/default/common/IdentityCredential.cpp b/identity/aidl/default/common/IdentityCredential.cpp
index 270fcfa..9477997 100644
--- a/identity/aidl/default/common/IdentityCredential.cpp
+++ b/identity/aidl/default/common/IdentityCredential.cpp
@@ -30,6 +30,7 @@
 #include <cppbor_parse.h>
 
 #include "FakeSecureHardwareProxy.h"
+#include "WritableIdentityCredential.h"
 
 namespace aidl::android::hardware::identity {
 
@@ -70,14 +71,8 @@
     docType_ = docTypeItem->value();
     testCredential_ = testCredentialItem->value();
 
-    const vector<uint8_t>& encryptedCredentialKeys = encryptedCredentialKeysItem->value();
-
-    if (encryptedCredentialKeys.size() != 80) {
-        LOG(ERROR) << "Unexpected size for encrypted CredentialKeys";
-        return IIdentityCredentialStore::STATUS_INVALID_DATA;
-    }
-
-    if (!hwProxy_->initialize(testCredential_, docType_, encryptedCredentialKeys)) {
+    encryptedCredentialKeys_ = encryptedCredentialKeysItem->value();
+    if (!hwProxy_->initialize(testCredential_, docType_, encryptedCredentialKeys_)) {
         LOG(ERROR) << "hwProxy->initialize failed";
         return false;
     }
@@ -87,12 +82,32 @@
 
 ndk::ScopedAStatus IdentityCredential::deleteCredential(
         vector<uint8_t>* outProofOfDeletionSignature) {
+    return deleteCredentialCommon({}, false, outProofOfDeletionSignature);
+}
+
+ndk::ScopedAStatus IdentityCredential::deleteCredentialWithChallenge(
+        const vector<uint8_t>& challenge, vector<uint8_t>* outProofOfDeletionSignature) {
+    return deleteCredentialCommon(challenge, true, outProofOfDeletionSignature);
+}
+
+ndk::ScopedAStatus IdentityCredential::deleteCredentialCommon(
+        const vector<uint8_t>& challenge, bool includeChallenge,
+        vector<uint8_t>* outProofOfDeletionSignature) {
+    if (challenge.size() > 32) {
+        return ndk::ScopedAStatus(AStatus_fromServiceSpecificErrorWithMessage(
+                IIdentityCredentialStore::STATUS_INVALID_DATA, "Challenge too big"));
+    }
+
     cppbor::Array array = {"ProofOfDeletion", docType_, testCredential_};
+    if (includeChallenge) {
+        array = {"ProofOfDeletion", docType_, challenge, testCredential_};
+    }
+
     vector<uint8_t> proofOfDeletionCbor = array.encode();
     vector<uint8_t> podDigest = support::sha256(proofOfDeletionCbor);
 
-    optional<vector<uint8_t>> signatureOfToBeSigned =
-            hwProxy_->deleteCredential(docType_, proofOfDeletionCbor.size());
+    optional<vector<uint8_t>> signatureOfToBeSigned = hwProxy_->deleteCredential(
+            docType_, challenge, includeChallenge, proofOfDeletionCbor.size());
     if (!signatureOfToBeSigned) {
         return ndk::ScopedAStatus(AStatus_fromServiceSpecificErrorWithMessage(
                 IIdentityCredentialStore::STATUS_FAILED, "Error signing ProofOfDeletion"));
@@ -111,6 +126,38 @@
     return ndk::ScopedAStatus::ok();
 }
 
+ndk::ScopedAStatus IdentityCredential::proveOwnership(
+        const vector<uint8_t>& challenge, vector<uint8_t>* outProofOfOwnershipSignature) {
+    if (challenge.size() > 32) {
+        return ndk::ScopedAStatus(AStatus_fromServiceSpecificErrorWithMessage(
+                IIdentityCredentialStore::STATUS_INVALID_DATA, "Challenge too big"));
+    }
+
+    cppbor::Array array;
+    array = {"ProofOfOwnership", docType_, challenge, testCredential_};
+    vector<uint8_t> proofOfOwnershipCbor = array.encode();
+    vector<uint8_t> podDigest = support::sha256(proofOfOwnershipCbor);
+
+    optional<vector<uint8_t>> signatureOfToBeSigned = hwProxy_->proveOwnership(
+            docType_, testCredential_, challenge, proofOfOwnershipCbor.size());
+    if (!signatureOfToBeSigned) {
+        return ndk::ScopedAStatus(AStatus_fromServiceSpecificErrorWithMessage(
+                IIdentityCredentialStore::STATUS_FAILED, "Error signing ProofOfOwnership"));
+    }
+
+    optional<vector<uint8_t>> signature =
+            support::coseSignEcDsaWithSignature(signatureOfToBeSigned.value(),
+                                                proofOfOwnershipCbor,  // data
+                                                {});                   // certificateChain
+    if (!signature) {
+        return ndk::ScopedAStatus(AStatus_fromServiceSpecificErrorWithMessage(
+                IIdentityCredentialStore::STATUS_FAILED, "Error signing data"));
+    }
+
+    *outProofOfOwnershipSignature = signature.value();
+    return ndk::ScopedAStatus::ok();
+}
+
 ndk::ScopedAStatus IdentityCredential::createEphemeralKeyPair(vector<uint8_t>* outKeyPair) {
     optional<vector<uint8_t>> ephemeralPriv = hwProxy_->createEphemeralKeyPair();
     if (!ephemeralPriv) {
@@ -833,4 +880,19 @@
     return ndk::ScopedAStatus::ok();
 }
 
+ndk::ScopedAStatus IdentityCredential::updateCredential(
+        shared_ptr<IWritableIdentityCredential>* outWritableCredential) {
+    sp<SecureHardwareProvisioningProxy> hwProxy = hwProxyFactory_->createProvisioningProxy();
+    shared_ptr<WritableIdentityCredential> wc =
+            ndk::SharedRefBase::make<WritableIdentityCredential>(hwProxy, docType_,
+                                                                 testCredential_);
+    if (!wc->initializeForUpdate(encryptedCredentialKeys_)) {
+        return ndk::ScopedAStatus(AStatus_fromServiceSpecificErrorWithMessage(
+                IIdentityCredentialStore::STATUS_FAILED,
+                "Error initializing WritableIdentityCredential for update"));
+    }
+    *outWritableCredential = wc;
+    return ndk::ScopedAStatus::ok();
+}
+
 }  // namespace aidl::android::hardware::identity
diff --git a/identity/aidl/default/common/IdentityCredential.h b/identity/aidl/default/common/IdentityCredential.h
index 2281821..9913b86 100644
--- a/identity/aidl/default/common/IdentityCredential.h
+++ b/identity/aidl/default/common/IdentityCredential.h
@@ -45,9 +45,11 @@
 
 class IdentityCredential : public BnIdentityCredential {
   public:
-    IdentityCredential(sp<SecureHardwarePresentationProxy> hwProxy,
+    IdentityCredential(sp<SecureHardwareProxyFactory> hwProxyFactory,
+                       sp<SecureHardwarePresentationProxy> hwProxy,
                        const vector<uint8_t>& credentialData)
-        : hwProxy_(hwProxy),
+        : hwProxyFactory_(hwProxyFactory),
+          hwProxy_(hwProxy),
           credentialData_(credentialData),
           numStartRetrievalCalls_(0),
           expectedDeviceNameSpacesSize_(0) {}
@@ -58,6 +60,11 @@
 
     // Methods from IIdentityCredential follow.
     ndk::ScopedAStatus deleteCredential(vector<uint8_t>* outProofOfDeletionSignature) override;
+    ndk::ScopedAStatus deleteCredentialWithChallenge(
+            const vector<uint8_t>& challenge,
+            vector<uint8_t>* outProofOfDeletionSignature) override;
+    ndk::ScopedAStatus proveOwnership(const vector<uint8_t>& challenge,
+                                      vector<uint8_t>* outProofOfOwnershipSignature) override;
     ndk::ScopedAStatus createEphemeralKeyPair(vector<uint8_t>* outKeyPair) override;
     ndk::ScopedAStatus setReaderEphemeralPublicKey(const vector<uint8_t>& publicKey) override;
     ndk::ScopedAStatus createAuthChallenge(int64_t* outChallenge) override;
@@ -79,8 +86,16 @@
     ndk::ScopedAStatus generateSigningKeyPair(vector<uint8_t>* outSigningKeyBlob,
                                               Certificate* outSigningKeyCertificate) override;
 
+    ndk::ScopedAStatus updateCredential(
+            shared_ptr<IWritableIdentityCredential>* outWritableCredential) override;
+
   private:
+    ndk::ScopedAStatus deleteCredentialCommon(const vector<uint8_t>& challenge,
+                                              bool includeChallenge,
+                                              vector<uint8_t>* outProofOfDeletionSignature);
+
     // Set by constructor
+    sp<SecureHardwareProxyFactory> hwProxyFactory_;
     sp<SecureHardwarePresentationProxy> hwProxy_;
     vector<uint8_t> credentialData_;
     int numStartRetrievalCalls_;
@@ -88,6 +103,7 @@
     // Set by initialize()
     string docType_;
     bool testCredential_;
+    vector<uint8_t> encryptedCredentialKeys_;
 
     // Set by createEphemeralKeyPair()
     vector<uint8_t> ephemeralPublicKey_;
diff --git a/identity/aidl/default/common/IdentityCredentialStore.cpp b/identity/aidl/default/common/IdentityCredentialStore.cpp
index 13f91aa..e6b5466 100644
--- a/identity/aidl/default/common/IdentityCredentialStore.cpp
+++ b/identity/aidl/default/common/IdentityCredentialStore.cpp
@@ -63,7 +63,7 @@
 
     sp<SecureHardwarePresentationProxy> hwProxy = hwProxyFactory_->createPresentationProxy();
     shared_ptr<IdentityCredential> credential =
-            ndk::SharedRefBase::make<IdentityCredential>(hwProxy, credentialData);
+            ndk::SharedRefBase::make<IdentityCredential>(hwProxyFactory_, hwProxy, credentialData);
     auto ret = credential->initialize();
     if (ret != IIdentityCredentialStore::STATUS_OK) {
         return ndk::ScopedAStatus(AStatus_fromServiceSpecificErrorWithMessage(
diff --git a/identity/aidl/default/common/SecureHardwareProxy.h b/identity/aidl/default/common/SecureHardwareProxy.h
index b89ad87..a1ed1ef 100644
--- a/identity/aidl/default/common/SecureHardwareProxy.h
+++ b/identity/aidl/default/common/SecureHardwareProxy.h
@@ -64,6 +64,9 @@
 
     virtual bool initialize(bool testCredential) = 0;
 
+    virtual bool initializeForUpdate(bool testCredential, string docType,
+                                     vector<uint8_t> encryptedCredentialKeys) = 0;
+
     // Returns public key certificate chain with attestation.
     //
     // This must return an entire certificate chain and its implementation must
@@ -164,8 +167,14 @@
     virtual optional<vector<uint8_t>> finishRetrieval();
 
     virtual optional<vector<uint8_t>> deleteCredential(const string& docType,
+                                                       const vector<uint8_t>& challenge,
+                                                       bool includeChallenge,
                                                        size_t proofOfDeletionCborSize) = 0;
 
+    virtual optional<vector<uint8_t>> proveOwnership(const string& docType, bool testCredential,
+                                                     const vector<uint8_t>& challenge,
+                                                     size_t proofOfOwnershipCborSize) = 0;
+
     virtual bool shutdown() = 0;
 };
 
diff --git a/identity/aidl/default/common/WritableIdentityCredential.cpp b/identity/aidl/default/common/WritableIdentityCredential.cpp
index 1328f36..2d897c7 100644
--- a/identity/aidl/default/common/WritableIdentityCredential.cpp
+++ b/identity/aidl/default/common/WritableIdentityCredential.cpp
@@ -40,7 +40,20 @@
 
 bool WritableIdentityCredential::initialize() {
     if (!hwProxy_->initialize(testCredential_)) {
-        LOG(ERROR) << "hwProxy->initialize failed";
+        LOG(ERROR) << "hwProxy->initialize() failed";
+        return false;
+    }
+    startPersonalizationCalled_ = false;
+    firstEntry_ = true;
+
+    return true;
+}
+
+// Used when updating a credential. Returns false on failure.
+bool WritableIdentityCredential::initializeForUpdate(
+        const vector<uint8_t>& encryptedCredentialKeys) {
+    if (!hwProxy_->initializeForUpdate(testCredential_, docType_, encryptedCredentialKeys)) {
+        LOG(ERROR) << "hwProxy->initializeForUpdate() failed";
         return false;
     }
     startPersonalizationCalled_ = false;
diff --git a/identity/aidl/default/common/WritableIdentityCredential.h b/identity/aidl/default/common/WritableIdentityCredential.h
index c6f0628..36ad430 100644
--- a/identity/aidl/default/common/WritableIdentityCredential.h
+++ b/identity/aidl/default/common/WritableIdentityCredential.h
@@ -36,16 +36,22 @@
 
 class WritableIdentityCredential : public BnWritableIdentityCredential {
   public:
+    // For a new credential, call initialize() right after construction.
+    //
+    // For an updated credential, call initializeForUpdate() right after construction.
+    //
     WritableIdentityCredential(sp<SecureHardwareProvisioningProxy> hwProxy, const string& docType,
                                bool testCredential)
         : hwProxy_(hwProxy), docType_(docType), testCredential_(testCredential) {}
 
     ~WritableIdentityCredential();
 
-    // Creates the Credential Key. Returns false on failure. Must be called
-    // right after construction.
+    // Creates the Credential Key. Returns false on failure.
     bool initialize();
 
+    // Used when updating a credential. Returns false on failure.
+    bool initializeForUpdate(const vector<uint8_t>& encryptedCredentialKeys);
+
     // Methods from IWritableIdentityCredential follow.
     ndk::ScopedAStatus getAttestationCertificate(const vector<uint8_t>& attestationApplicationId,
                                                  const vector<uint8_t>& attestationChallenge,
diff --git a/identity/aidl/default/identity-default.xml b/identity/aidl/default/identity-default.xml
index 37d5b81..a074250 100644
--- a/identity/aidl/default/identity-default.xml
+++ b/identity/aidl/default/identity-default.xml
@@ -1,7 +1,7 @@
 <manifest version="1.0" type="device">
     <hal format="aidl">
         <name>android.hardware.identity</name>
-        <version>2</version>
+        <version>3</version>
         <interface>
             <name>IIdentityCredentialStore</name>
             <instance>default</instance>
diff --git a/identity/aidl/default/libeic/EicCbor.c b/identity/aidl/default/libeic/EicCbor.c
index ec049b1..fe131eb 100644
--- a/identity/aidl/default/libeic/EicCbor.c
+++ b/identity/aidl/default/libeic/EicCbor.c
@@ -17,6 +17,7 @@
 #include "EicCbor.h"
 
 void eicCborInit(EicCbor* cbor, uint8_t* buffer, size_t bufferSize) {
+    eicMemSet(cbor, '\0', sizeof(EicCbor));
     cbor->size = 0;
     cbor->bufferSize = bufferSize;
     cbor->buffer = buffer;
@@ -26,6 +27,7 @@
 
 void eicCborInitHmacSha256(EicCbor* cbor, uint8_t* buffer, size_t bufferSize,
                            const uint8_t* hmacKey, size_t hmacKeySize) {
+    eicMemSet(cbor, '\0', sizeof(EicCbor));
     cbor->size = 0;
     cbor->bufferSize = bufferSize;
     cbor->buffer = buffer;
@@ -33,6 +35,10 @@
     eicOpsHmacSha256Init(&cbor->digester.hmacSha256, hmacKey, hmacKeySize);
 }
 
+void eicCborEnableSecondaryDigesterSha256(EicCbor* cbor, EicSha256Ctx* sha256) {
+    cbor->secondaryDigesterSha256 = sha256;
+}
+
 void eicCborFinal(EicCbor* cbor, uint8_t digest[EIC_SHA256_DIGEST_SIZE]) {
     switch (cbor->digestType) {
         case EIC_CBOR_DIGEST_TYPE_SHA256:
@@ -53,6 +59,9 @@
             eicOpsHmacSha256Update(&cbor->digester.hmacSha256, data, size);
             break;
     }
+    if (cbor->secondaryDigesterSha256 != NULL) {
+        eicOpsSha256Update(cbor->secondaryDigesterSha256, data, size);
+    }
 
     if (cbor->size >= cbor->bufferSize) {
         cbor->size += size;
diff --git a/identity/aidl/default/libeic/EicCbor.h b/identity/aidl/default/libeic/EicCbor.h
index 4686b38..9c0f531 100644
--- a/identity/aidl/default/libeic/EicCbor.h
+++ b/identity/aidl/default/libeic/EicCbor.h
@@ -53,6 +53,9 @@
         EicHmacSha256Ctx hmacSha256;
     } digester;
 
+    // The secondary digester, may be unset.
+    EicSha256Ctx* secondaryDigesterSha256;
+
     // The buffer used for building up CBOR or NULL if bufferSize is 0.
     uint8_t* buffer;
 } EicCbor;
@@ -70,6 +73,14 @@
 void eicCborInitHmacSha256(EicCbor* cbor, uint8_t* buffer, size_t bufferSize,
                            const uint8_t* hmacKey, size_t hmacKeySize);
 
+/* Enables a secondary digester.
+ *
+ * May be enabled midway through processing, this can be used to e.g. calculate
+ * a digest of Sig_structure (for COSE_Sign1) and a separate digest of its
+ * payload.
+ */
+void eicCborEnableSecondaryDigesterSha256(EicCbor* cbor, EicSha256Ctx* sha256);
+
 /* Finishes building CBOR and returns the digest. */
 void eicCborFinal(EicCbor* cbor, uint8_t digest[EIC_SHA256_DIGEST_SIZE]);
 
diff --git a/identity/aidl/default/libeic/EicOps.h b/identity/aidl/default/libeic/EicOps.h
index da4dabf..d4fcf0e 100644
--- a/identity/aidl/default/libeic/EicOps.h
+++ b/identity/aidl/default/libeic/EicOps.h
@@ -207,14 +207,17 @@
 // Generate an X.509 certificate for the key identified by |publicKey| which
 // must be of the form returned by eicOpsCreateEcKey().
 //
+// If proofOfBinding is not NULL, it will be included as an OCTET_STRING
+// X.509 extension at OID 1.3.6.1.4.1.11129.2.1.26.
+//
 // The certificate will be signed by the key identified by |signingKey| which
 // must be of the form returned by eicOpsCreateEcKey().
 //
 bool eicOpsSignEcKey(const uint8_t publicKey[EIC_P256_PUB_KEY_SIZE],
                      const uint8_t signingKey[EIC_P256_PRIV_KEY_SIZE], unsigned int serial,
                      const char* issuerName, const char* subjectName, time_t validityNotBefore,
-                     time_t validityNotAfter, uint8_t* cert,
-                     size_t* certSize);  // inout
+                     time_t validityNotAfter, const uint8_t* proofOfBinding,
+                     size_t proofOfBindingSize, uint8_t* cert, size_t* certSize);  // inout
 
 // Uses |privateKey| to create an ECDSA signature of some data (the SHA-256 must
 // be given by |digestOfData|). Returns the signature in |signature|.
diff --git a/identity/aidl/default/libeic/EicPresentation.c b/identity/aidl/default/libeic/EicPresentation.c
index d3f5556..5e9a280 100644
--- a/identity/aidl/default/libeic/EicPresentation.c
+++ b/identity/aidl/default/libeic/EicPresentation.c
@@ -19,13 +19,28 @@
 #include <inttypes.h>
 
 bool eicPresentationInit(EicPresentation* ctx, bool testCredential, const char* docType,
-                         const uint8_t encryptedCredentialKeys[80]) {
-    uint8_t credentialKeys[52];
+                         const uint8_t* encryptedCredentialKeys,
+                         size_t encryptedCredentialKeysSize) {
+    uint8_t credentialKeys[86];
+    bool expectPopSha256 = false;
+
+    // For feature version 202009 it's 52 bytes long and for feature version 202101 it's 86
+    // bytes (the additional data is the ProofOfProvisioning SHA-256). We need
+    // to support loading all feature versions.
+    //
+    if (encryptedCredentialKeysSize == 52 + 28) {
+        /* do nothing */
+    } else if (encryptedCredentialKeysSize == 86 + 28) {
+        expectPopSha256 = true;
+    } else {
+        eicDebug("Unexpected size %zd for encryptedCredentialKeys", encryptedCredentialKeysSize);
+        return false;
+    }
 
     eicMemSet(ctx, '\0', sizeof(EicPresentation));
 
     if (!eicOpsDecryptAes128Gcm(eicOpsGetHardwareBoundKey(testCredential), encryptedCredentialKeys,
-                                80,
+                                encryptedCredentialKeysSize,
                                 // DocType is the additionalAuthenticatedData
                                 (const uint8_t*)docType, eicStrLen(docType), credentialKeys)) {
         eicDebug("Error decrypting CredentialKeys");
@@ -34,25 +49,42 @@
 
     // It's supposed to look like this;
     //
+    // Feature version 202009:
+    //
     //         CredentialKeys = [
     //              bstr,   ; storageKey, a 128-bit AES key
-    //              bstr    ; credentialPrivKey, the private key for credentialKey
+    //              bstr,   ; credentialPrivKey, the private key for credentialKey
     //         ]
     //
-    // where storageKey is 16 bytes and credentialPrivateKey is 32 bytes.
+    // Feature version 202101:
     //
-    // So the first two bytes will be 0x82 0x50 indicating resp. an array of two elements
-    // and a bstr of 16 elements. Sixteen bytes later (offset 18 and 19) there will be
-    // a bstr of 32 bytes. It's encoded as two bytes 0x58 and 0x20.
+    //         CredentialKeys = [
+    //              bstr,   ; storageKey, a 128-bit AES key
+    //              bstr,   ; credentialPrivKey, the private key for credentialKey
+    //              bstr    ; proofOfProvisioning SHA-256
+    //         ]
     //
-    if (credentialKeys[0] != 0x82 || credentialKeys[1] != 0x50 || credentialKeys[18] != 0x58 ||
-        credentialKeys[19] != 0x20) {
+    // where storageKey is 16 bytes, credentialPrivateKey is 32 bytes, and proofOfProvisioning
+    // SHA-256 is 32 bytes.
+    //
+    if (credentialKeys[0] != (expectPopSha256 ? 0x83 : 0x82) ||  // array of two or three elements
+        credentialKeys[1] != 0x50 ||                             // 16-byte bstr
+        credentialKeys[18] != 0x58 || credentialKeys[19] != 0x20) {  // 32-byte bstr
         eicDebug("Invalid CBOR for CredentialKeys");
         return false;
     }
+    if (expectPopSha256) {
+        if (credentialKeys[52] != 0x58 || credentialKeys[53] != 0x20) {  // 32-byte bstr
+            eicDebug("Invalid CBOR for CredentialKeys");
+            return false;
+        }
+    }
     eicMemCpy(ctx->storageKey, credentialKeys + 2, EIC_AES_128_KEY_SIZE);
     eicMemCpy(ctx->credentialPrivateKey, credentialKeys + 20, EIC_P256_PRIV_KEY_SIZE);
     ctx->testCredential = testCredential;
+    if (expectPopSha256) {
+        eicMemCpy(ctx->proofOfProvisioningSha256, credentialKeys + 54, EIC_SHA256_DIGEST_SIZE);
+    }
     return true;
 }
 
@@ -61,6 +93,35 @@
                                            uint8_t signingKeyBlob[60]) {
     uint8_t signingKeyPriv[EIC_P256_PRIV_KEY_SIZE];
     uint8_t signingKeyPub[EIC_P256_PUB_KEY_SIZE];
+    uint8_t cborBuf[64];
+
+    // Generate the ProofOfBinding CBOR to include in the X.509 certificate in
+    // IdentityCredentialAuthenticationKeyExtension CBOR. This CBOR is defined
+    // by the following CDDL
+    //
+    //   ProofOfBinding = [
+    //     "ProofOfBinding",
+    //     bstr,                  // Contains the SHA-256 of ProofOfProvisioning
+    //   ]
+    //
+    // This array may grow in the future if other information needs to be
+    // conveyed.
+    //
+    // The bytes of ProofOfBinding is is represented as an OCTET_STRING
+    // and stored at OID 1.3.6.1.4.1.11129.2.1.26.
+    //
+
+    EicCbor cbor;
+    eicCborInit(&cbor, cborBuf, sizeof cborBuf);
+    eicCborAppendArray(&cbor, 2);
+    eicCborAppendString(&cbor, "ProofOfBinding");
+    eicCborAppendByteString(&cbor, ctx->proofOfProvisioningSha256, EIC_SHA256_DIGEST_SIZE);
+    if (cbor.size > sizeof(cborBuf)) {
+        eicDebug("Exceeded buffer size");
+        return false;
+    }
+    const uint8_t* proofOfBinding = cborBuf;
+    size_t proofOfBindingSize = cbor.size;
 
     if (!eicOpsCreateEcKey(signingKeyPriv, signingKeyPub)) {
         eicDebug("Error creating signing key");
@@ -73,7 +134,8 @@
     if (!eicOpsSignEcKey(signingKeyPub, ctx->credentialPrivateKey, 1,
                          "Android Identity Credential Key",                 // issuer CN
                          "Android Identity Credential Authentication Key",  // subject CN
-                         validityNotBefore, validityNotAfter, publicKeyCert, publicKeyCertSize)) {
+                         validityNotBefore, validityNotAfter, proofOfBinding, proofOfBindingSize,
+                         publicKeyCert, publicKeyCertSize)) {
         eicDebug("Error creating certificate for signing key");
         return false;
     }
@@ -674,7 +736,8 @@
 }
 
 bool eicPresentationDeleteCredential(EicPresentation* ctx, const char* docType,
-                                     size_t proofOfDeletionCborSize,
+                                     const uint8_t* challenge, size_t challengeSize,
+                                     bool includeChallenge, size_t proofOfDeletionCborSize,
                                      uint8_t signatureOfToBeSigned[EIC_ECDSA_P256_SIGNATURE_SIZE]) {
     EicCbor cbor;
 
@@ -712,9 +775,12 @@
     eicCborBegin(&cbor, EIC_CBOR_MAJOR_TYPE_BYTE_STRING, proofOfDeletionCborSize);
 
     // Finally, the CBOR that we're actually signing.
-    eicCborAppendArray(&cbor, 3);
+    eicCborAppendArray(&cbor, includeChallenge ? 4 : 3);
     eicCborAppendString(&cbor, "ProofOfDeletion");
     eicCborAppendString(&cbor, docType);
+    if (includeChallenge) {
+        eicCborAppendByteString(&cbor, challenge, challengeSize);
+    }
     eicCborAppendBool(&cbor, ctx->testCredential);
 
     uint8_t cborSha256[EIC_SHA256_DIGEST_SIZE];
@@ -726,3 +792,59 @@
 
     return true;
 }
+
+bool eicPresentationProveOwnership(EicPresentation* ctx, const char* docType, bool testCredential,
+                                   const uint8_t* challenge, size_t challengeSize,
+                                   size_t proofOfOwnershipCborSize,
+                                   uint8_t signatureOfToBeSigned[EIC_ECDSA_P256_SIGNATURE_SIZE]) {
+    EicCbor cbor;
+
+    eicCborInit(&cbor, NULL, 0);
+
+    // What we're going to sign is the COSE ToBeSigned structure which
+    // looks like the following:
+    //
+    // Sig_structure = [
+    //   context : "Signature" / "Signature1" / "CounterSignature",
+    //   body_protected : empty_or_serialized_map,
+    //   ? sign_protected : empty_or_serialized_map,
+    //   external_aad : bstr,
+    //   payload : bstr
+    //  ]
+    //
+    eicCborAppendArray(&cbor, 4);
+    eicCborAppendString(&cbor, "Signature1");
+
+    // The COSE Encoded protected headers is just a single field with
+    // COSE_LABEL_ALG (1) -> COSE_ALG_ECSDA_256 (-7). For simplicitly we just
+    // hard-code the CBOR encoding:
+    static const uint8_t coseEncodedProtectedHeaders[] = {0xa1, 0x01, 0x26};
+    eicCborAppendByteString(&cbor, coseEncodedProtectedHeaders,
+                            sizeof(coseEncodedProtectedHeaders));
+
+    // We currently don't support Externally Supplied Data (RFC 8152 section 4.3)
+    // so external_aad is the empty bstr
+    static const uint8_t externalAad[0] = {};
+    eicCborAppendByteString(&cbor, externalAad, sizeof(externalAad));
+
+    // For the payload, the _encoded_ form follows here. We handle this by simply
+    // opening a bstr, and then writing the CBOR. This requires us to know the
+    // size of said bstr, ahead of time.
+    eicCborBegin(&cbor, EIC_CBOR_MAJOR_TYPE_BYTE_STRING, proofOfOwnershipCborSize);
+
+    // Finally, the CBOR that we're actually signing.
+    eicCborAppendArray(&cbor, 4);
+    eicCborAppendString(&cbor, "ProofOfOwnership");
+    eicCborAppendString(&cbor, docType);
+    eicCborAppendByteString(&cbor, challenge, challengeSize);
+    eicCborAppendBool(&cbor, testCredential);
+
+    uint8_t cborSha256[EIC_SHA256_DIGEST_SIZE];
+    eicCborFinal(&cbor, cborSha256);
+    if (!eicOpsEcDsa(ctx->credentialPrivateKey, cborSha256, signatureOfToBeSigned)) {
+        eicDebug("Error signing proofOfDeletion");
+        return false;
+    }
+
+    return true;
+}
diff --git a/identity/aidl/default/libeic/EicPresentation.h b/identity/aidl/default/libeic/EicPresentation.h
index d798962..7cad068 100644
--- a/identity/aidl/default/libeic/EicPresentation.h
+++ b/identity/aidl/default/libeic/EicPresentation.h
@@ -31,6 +31,8 @@
 #define EIC_PRESENTATION_MAX_READER_PUBLIC_KEY_SIZE 65
 
 typedef struct {
+    int featureLevel;
+
     uint8_t storageKey[EIC_AES_128_KEY_SIZE];
     uint8_t credentialPrivateKey[EIC_P256_PRIV_KEY_SIZE];
 
@@ -79,12 +81,17 @@
     // SHA-256 for AdditionalData, updated for each entry.
     uint8_t additionalDataSha256[EIC_SHA256_DIGEST_SIZE];
 
+    // SHA-256 of ProofOfProvisioning. Set to NUL-bytes or initialized from CredentialKeys data
+    // if credential was created with feature version 202101 or later.
+    uint8_t proofOfProvisioningSha256[EIC_SHA256_DIGEST_SIZE];
+
     size_t expectedCborSizeAtEnd;
     EicCbor cbor;
 } EicPresentation;
 
 bool eicPresentationInit(EicPresentation* ctx, bool testCredential, const char* docType,
-                         const uint8_t encryptedCredentialKeys[80]);
+                         const uint8_t* encryptedCredentialKeys,
+                         size_t encryptedCredentialKeysSize);
 
 bool eicPresentationGenerateSigningKeyPair(EicPresentation* ctx, const char* docType, time_t now,
                                            uint8_t* publicKeyCert, size_t* publicKeyCertSize,
@@ -219,9 +226,19 @@
 // where content is set to the ProofOfDeletion CBOR.
 //
 bool eicPresentationDeleteCredential(EicPresentation* ctx, const char* docType,
-                                     size_t proofOfDeletionCborSize,
+                                     const uint8_t* challenge, size_t challengeSize,
+                                     bool includeChallenge, size_t proofOfDeletionCborSize,
                                      uint8_t signatureOfToBeSigned[EIC_ECDSA_P256_SIGNATURE_SIZE]);
 
+// The data returned in |signatureOfToBeSigned| contains the ECDSA signature of
+// the ToBeSigned CBOR from RFC 8051 "4.4. Signing and Verification Process"
+// where content is set to the ProofOfOwnership CBOR.
+//
+bool eicPresentationProveOwnership(EicPresentation* ctx, const char* docType, bool testCredential,
+                                   const uint8_t* challenge, size_t challengeSize,
+                                   size_t proofOfOwnershipCborSize,
+                                   uint8_t signatureOfToBeSigned[EIC_ECDSA_P256_SIGNATURE_SIZE]);
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/identity/aidl/default/libeic/EicProvisioning.c b/identity/aidl/default/libeic/EicProvisioning.c
index f16605c..3b4148e 100644
--- a/identity/aidl/default/libeic/EicProvisioning.c
+++ b/identity/aidl/default/libeic/EicProvisioning.c
@@ -26,10 +26,84 @@
     return true;
 }
 
+bool eicProvisioningInitForUpdate(EicProvisioning* ctx, bool testCredential, const char* docType,
+                                  const uint8_t* encryptedCredentialKeys,
+                                  size_t encryptedCredentialKeysSize) {
+    uint8_t credentialKeys[86];
+
+    // For feature version 202009 it's 52 bytes long and for feature version 202101 it's 86
+    // bytes (the additional data is the ProofOfProvisioning SHA-256). We need
+    // to support loading all feature versions.
+    //
+    bool expectPopSha256 = false;
+    if (encryptedCredentialKeysSize == 52 + 28) {
+        /* do nothing */
+    } else if (encryptedCredentialKeysSize == 86 + 28) {
+        expectPopSha256 = true;
+    } else {
+        eicDebug("Unexpected size %zd for encryptedCredentialKeys", encryptedCredentialKeysSize);
+        return false;
+    }
+
+    eicMemSet(ctx, '\0', sizeof(EicProvisioning));
+    ctx->testCredential = testCredential;
+
+    if (!eicOpsDecryptAes128Gcm(eicOpsGetHardwareBoundKey(testCredential), encryptedCredentialKeys,
+                                encryptedCredentialKeysSize,
+                                // DocType is the additionalAuthenticatedData
+                                (const uint8_t*)docType, eicStrLen(docType), credentialKeys)) {
+        eicDebug("Error decrypting CredentialKeys");
+        return false;
+    }
+
+    // It's supposed to look like this;
+    //
+    // Feature version 202009:
+    //
+    //         CredentialKeys = [
+    //              bstr,   ; storageKey, a 128-bit AES key
+    //              bstr,   ; credentialPrivKey, the private key for credentialKey
+    //         ]
+    //
+    // Feature version 202101:
+    //
+    //         CredentialKeys = [
+    //              bstr,   ; storageKey, a 128-bit AES key
+    //              bstr,   ; credentialPrivKey, the private key for credentialKey
+    //              bstr    ; proofOfProvisioning SHA-256
+    //         ]
+    //
+    // where storageKey is 16 bytes, credentialPrivateKey is 32 bytes, and proofOfProvisioning
+    // SHA-256 is 32 bytes.
+    //
+    if (credentialKeys[0] != (expectPopSha256 ? 0x83 : 0x82) ||  // array of two or three elements
+        credentialKeys[1] != 0x50 ||                             // 16-byte bstr
+        credentialKeys[18] != 0x58 || credentialKeys[19] != 0x20) {  // 32-byte bstr
+        eicDebug("Invalid CBOR for CredentialKeys");
+        return false;
+    }
+    if (expectPopSha256) {
+        if (credentialKeys[52] != 0x58 || credentialKeys[53] != 0x20) {  // 32-byte bstr
+            eicDebug("Invalid CBOR for CredentialKeys");
+            return false;
+        }
+    }
+    eicMemCpy(ctx->storageKey, credentialKeys + 2, EIC_AES_128_KEY_SIZE);
+    eicMemCpy(ctx->credentialPrivateKey, credentialKeys + 20, EIC_P256_PRIV_KEY_SIZE);
+    // Note: We don't care about the previous ProofOfProvisioning SHA-256
+    ctx->isUpdate = true;
+    return true;
+}
+
 bool eicProvisioningCreateCredentialKey(EicProvisioning* ctx, const uint8_t* challenge,
                                         size_t challengeSize, const uint8_t* applicationId,
                                         size_t applicationIdSize, uint8_t* publicKeyCert,
                                         size_t* publicKeyCertSize) {
+    if (ctx->isUpdate) {
+        eicDebug("Cannot create CredentialKey on update");
+        return false;
+    }
+
     if (!eicOpsCreateCredentialKey(ctx->credentialPrivateKey, challenge, challengeSize,
                                    applicationId, applicationIdSize, ctx->testCredential,
                                    publicKeyCert, publicKeyCertSize)) {
@@ -96,6 +170,9 @@
     eicCborBegin(&ctx->cbor, EIC_CBOR_MAJOR_TYPE_BYTE_STRING, expectedProofOfProvisioningSize);
     ctx->expectedCborSizeAtEnd = expectedProofOfProvisioningSize + ctx->cbor.size;
 
+    eicOpsSha256Init(&ctx->proofOfProvisioningDigester);
+    eicCborEnableSecondaryDigesterSha256(&ctx->cbor, &ctx->proofOfProvisioningDigester);
+
     eicCborAppendArray(&ctx->cbor, 5);
     eicCborAppendString(&ctx->cbor, "ProofOfProvisioning");
     eicCborAppendString(&ctx->cbor, docType);
@@ -260,14 +337,23 @@
 }
 
 bool eicProvisioningFinishGetCredentialData(EicProvisioning* ctx, const char* docType,
-                                            uint8_t encryptedCredentialKeys[80]) {
+                                            uint8_t* encryptedCredentialKeys,
+                                            size_t* encryptedCredentialKeysSize) {
     EicCbor cbor;
-    uint8_t cborBuf[52];
+    uint8_t cborBuf[86];
+
+    if (*encryptedCredentialKeysSize < 86 + 28) {
+        eicDebug("encryptedCredentialKeysSize is %zd which is insufficient");
+        return false;
+    }
 
     eicCborInit(&cbor, cborBuf, sizeof(cborBuf));
-    eicCborAppendArray(&cbor, 2);
+    eicCborAppendArray(&cbor, 3);
     eicCborAppendByteString(&cbor, ctx->storageKey, EIC_AES_128_KEY_SIZE);
     eicCborAppendByteString(&cbor, ctx->credentialPrivateKey, EIC_P256_PRIV_KEY_SIZE);
+    uint8_t popSha256[EIC_SHA256_DIGEST_SIZE];
+    eicOpsSha256Final(&ctx->proofOfProvisioningDigester, popSha256);
+    eicCborAppendByteString(&cbor, popSha256, EIC_SHA256_DIGEST_SIZE);
     if (cbor.size > sizeof(cborBuf)) {
         eicDebug("Exceeded buffer size");
         return false;
@@ -285,6 +371,7 @@
         eicDebug("Error encrypting CredentialKeys");
         return false;
     }
+    *encryptedCredentialKeysSize = cbor.size + 28;
 
     return true;
 }
diff --git a/identity/aidl/default/libeic/EicProvisioning.h b/identity/aidl/default/libeic/EicProvisioning.h
index 836d16e..f064787 100644
--- a/identity/aidl/default/libeic/EicProvisioning.h
+++ b/identity/aidl/default/libeic/EicProvisioning.h
@@ -31,7 +31,7 @@
 #define EIC_MAX_NUM_ACCESS_CONTROL_PROFILE_IDS 32
 
 typedef struct {
-    // Set by eicCreateCredentialKey.
+    // Set by eicCreateCredentialKey() OR eicProvisioningInitForUpdate()
     uint8_t credentialPrivateKey[EIC_P256_PRIV_KEY_SIZE];
 
     int numEntryCounts;
@@ -43,6 +43,7 @@
     size_t curEntrySize;
     size_t curEntryNumBytesReceived;
 
+    // Set by eicProvisioningInit() OR eicProvisioningInitForUpdate()
     uint8_t storageKey[EIC_AES_128_KEY_SIZE];
 
     size_t expectedCborSizeAtEnd;
@@ -50,13 +51,23 @@
     // SHA-256 for AdditionalData, updated for each entry.
     uint8_t additionalDataSha256[EIC_SHA256_DIGEST_SIZE];
 
+    // Digester just for ProofOfProvisioning (without Sig_structure).
+    EicSha256Ctx proofOfProvisioningDigester;
+
     EicCbor cbor;
 
     bool testCredential;
+
+    // Set to true if this is an update.
+    bool isUpdate;
 } EicProvisioning;
 
 bool eicProvisioningInit(EicProvisioning* ctx, bool testCredential);
 
+bool eicProvisioningInitForUpdate(EicProvisioning* ctx, bool testCredential, const char* docType,
+                                  const uint8_t* encryptedCredentialKeys,
+                                  size_t encryptedCredentialKeysSize);
+
 bool eicProvisioningCreateCredentialKey(EicProvisioning* ctx, const uint8_t* challenge,
                                         size_t challengeSize, const uint8_t* applicationId,
                                         size_t applicationIdSize, uint8_t* publicKeyCert,
@@ -107,14 +118,18 @@
 //   CredentialKeys = [
 //     bstr,   ; storageKey, a 128-bit AES key
 //     bstr    ; credentialPrivKey, the private key for credentialKey
+//     bstr    ; SHA-256(ProofOfProvisioning)
 //   ]
 //
+// for feature version 202101. For feature version 202009 the third field was not present.
+//
 // Since |storageKey| is 16 bytes and |credentialPrivKey| is 32 bytes, the
-// encoded CBOR for CredentialKeys is 52 bytes and consequently
-// |encryptedCredentialKeys| will be 52 + 28 = 80 bytes.
+// encoded CBOR for CredentialKeys is 86 bytes and consequently
+// |encryptedCredentialKeys| will be no longer than 86 + 28 = 114 bytes.
 //
 bool eicProvisioningFinishGetCredentialData(EicProvisioning* ctx, const char* docType,
-                                            uint8_t encryptedCredentialKeys[80]);
+                                            uint8_t* encryptedCredentialKeys,
+                                            size_t* encryptedCredentialKeysSize);
 
 #ifdef __cplusplus
 }
diff --git a/identity/aidl/vts/Android.bp b/identity/aidl/vts/Android.bp
index 03966de..f1b1bcf 100644
--- a/identity/aidl/vts/Android.bp
+++ b/identity/aidl/vts/Android.bp
@@ -4,13 +4,21 @@
         "VtsHalTargetTestDefaults",
         "use_libaidlvintf_gtest_helper_static",
     ],
+    cflags: [
+        "-Wno-deprecated-declarations",
+    ],
     srcs: [
-        "VtsHalIdentityEndToEndTest.cpp",
         "VtsIWritableIdentityCredentialTests.cpp",
-        "VtsIdentityTestUtils.cpp",
+        "Util.cpp",
         "VtsAttestationTests.cpp",
         "UserAuthTests.cpp",
         "ReaderAuthTests.cpp",
+        "DeleteCredentialTests.cpp",
+        "ProveOwnershipTests.cpp",
+        "UpdateCredentialTests.cpp",
+        "EndToEndTests.cpp",
+        "TestCredentialTests.cpp",
+        "AuthenticationKeyTests.cpp",
     ],
     shared_libs: [
         "libbinder",
@@ -22,9 +30,9 @@
         "libpuresoftkeymasterdevice",
         "android.hardware.keymaster@4.0",
         "android.hardware.identity-support-lib",
-        "android.hardware.identity-cpp",
-        "android.hardware.keymaster-cpp",
-        "android.hardware.keymaster-ndk_platform",
+        "android.hardware.identity-unstable-cpp",
+        "android.hardware.keymaster-unstable-cpp",
+        "android.hardware.keymaster-unstable-ndk_platform",
         "libkeymaster4support",
         "libkeymaster4_1support",
     ],
diff --git a/identity/aidl/vts/AuthenticationKeyTests.cpp b/identity/aidl/vts/AuthenticationKeyTests.cpp
new file mode 100644
index 0000000..bda3e70
--- /dev/null
+++ b/identity/aidl/vts/AuthenticationKeyTests.cpp
@@ -0,0 +1,194 @@
+/*
+ * Copyright (C) 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#define LOG_TAG "TestCredentialTests"
+
+#include <aidl/Gtest.h>
+#include <aidl/Vintf.h>
+#include <aidl/android/hardware/keymaster/HardwareAuthToken.h>
+#include <aidl/android/hardware/keymaster/VerificationToken.h>
+#include <android-base/logging.h>
+#include <android/hardware/identity/IIdentityCredentialStore.h>
+#include <android/hardware/identity/support/IdentityCredentialSupport.h>
+#include <binder/IServiceManager.h>
+#include <binder/ProcessState.h>
+#include <cppbor.h>
+#include <cppbor_parse.h>
+#include <gtest/gtest.h>
+#include <future>
+#include <map>
+#include <utility>
+
+#include "Util.h"
+
+namespace android::hardware::identity {
+
+using std::endl;
+using std::make_pair;
+using std::map;
+using std::optional;
+using std::pair;
+using std::string;
+using std::tie;
+using std::vector;
+
+using ::android::sp;
+using ::android::String16;
+using ::android::binder::Status;
+
+using ::android::hardware::keymaster::HardwareAuthToken;
+using ::android::hardware::keymaster::VerificationToken;
+
+class AuthenticationKeyTests : public testing::TestWithParam<string> {
+  public:
+    virtual void SetUp() override {
+        string halInstanceName = GetParam();
+        credentialStore_ = android::waitForDeclaredService<IIdentityCredentialStore>(
+                String16(halInstanceName.c_str()));
+        ASSERT_NE(credentialStore_, nullptr);
+        halApiVersion_ = credentialStore_->getInterfaceVersion();
+    }
+
+    sp<IIdentityCredentialStore> credentialStore_;
+    int halApiVersion_;
+};
+
+TEST_P(AuthenticationKeyTests, proofOfProvisionInAuthKeyCert) {
+    if (halApiVersion_ < 3) {
+        GTEST_SKIP() << "Need HAL API version 3, have " << halApiVersion_;
+    }
+
+    string docType = "org.iso.18013-5.2019.mdl";
+    sp<IWritableIdentityCredential> wc;
+    ASSERT_TRUE(credentialStore_
+                        ->createCredential(docType,
+                                           true,  // testCredential
+                                           &wc)
+                        .isOk());
+
+    vector<uint8_t> attestationApplicationId = {};
+    vector<uint8_t> attestationChallenge = {1};
+    vector<Certificate> certChain;
+    ASSERT_TRUE(wc->getAttestationCertificate(attestationApplicationId, attestationChallenge,
+                                              &certChain)
+                        .isOk());
+
+    optional<vector<uint8_t>> optCredentialPubKey =
+            support::certificateChainGetTopMostKey(certChain[0].encodedCertificate);
+    ASSERT_TRUE(optCredentialPubKey);
+    vector<uint8_t> credentialPubKey;
+    credentialPubKey = optCredentialPubKey.value();
+
+    size_t proofOfProvisioningSize = 112;
+    // Not in v1 HAL, may fail
+    wc->setExpectedProofOfProvisioningSize(proofOfProvisioningSize);
+
+    ASSERT_TRUE(wc->startPersonalization(1 /* numAccessControlProfiles */,
+                                         {1} /* numDataElementsPerNamespace */)
+                        .isOk());
+
+    // Access control profile 0: open access - don't care about the returned SACP
+    SecureAccessControlProfile sacp;
+    ASSERT_TRUE(wc->addAccessControlProfile(1, {}, false, 0, 0, &sacp).isOk());
+
+    // Single entry - don't care about the returned encrypted data
+    vector<uint8_t> encryptedData;
+    vector<uint8_t> tstrLastName = cppbor::Tstr("Turing").encode();
+    ASSERT_TRUE(wc->beginAddEntry({1}, "ns", "Last name", tstrLastName.size()).isOk());
+    ASSERT_TRUE(wc->addEntryValue(tstrLastName, &encryptedData).isOk());
+
+    vector<uint8_t> proofOfProvisioningSignature;
+    vector<uint8_t> credentialData;
+    Status status = wc->finishAddingEntries(&credentialData, &proofOfProvisioningSignature);
+    EXPECT_TRUE(status.isOk()) << status.exceptionCode() << ": " << status.exceptionMessage();
+
+    optional<vector<uint8_t>> proofOfProvisioning =
+            support::coseSignGetPayload(proofOfProvisioningSignature);
+    ASSERT_TRUE(proofOfProvisioning);
+    string cborPretty = support::cborPrettyPrint(proofOfProvisioning.value(), 32, {});
+    EXPECT_EQ(
+            "[\n"
+            "  'ProofOfProvisioning',\n"
+            "  'org.iso.18013-5.2019.mdl',\n"
+            "  [\n"
+            "    {\n"
+            "      'id' : 1,\n"
+            "    },\n"
+            "  ],\n"
+            "  {\n"
+            "    'ns' : [\n"
+            "      {\n"
+            "        'name' : 'Last name',\n"
+            "        'value' : 'Turing',\n"
+            "        'accessControlProfiles' : [1, ],\n"
+            "      },\n"
+            "    ],\n"
+            "  },\n"
+            "  true,\n"
+            "]",
+            cborPretty);
+    // Make sure it's signed by the CredentialKey in the returned cert chain.
+    EXPECT_TRUE(support::coseCheckEcDsaSignature(proofOfProvisioningSignature,
+                                                 {},  // Additional data
+                                                 credentialPubKey));
+
+    // Now get a credential and have it create AuthenticationKey so we can check
+    // the certificate.
+    sp<IIdentityCredential> credential;
+    ASSERT_TRUE(credentialStore_
+                        ->getCredential(
+                                CipherSuite::CIPHERSUITE_ECDHE_HKDF_ECDSA_WITH_AES_256_GCM_SHA256,
+                                credentialData, &credential)
+                        .isOk());
+    vector<uint8_t> signingKeyBlob;
+    Certificate signingKeyCertificate;
+    ASSERT_TRUE(credential->generateSigningKeyPair(&signingKeyBlob, &signingKeyCertificate).isOk());
+    optional<vector<uint8_t>> signingPubKey =
+            support::certificateChainGetTopMostKey(signingKeyCertificate.encodedCertificate);
+    EXPECT_TRUE(signingPubKey);
+
+    // SHA-256(ProofOfProvisioning) is embedded in CBOR with the following CDDL
+    //
+    //   ProofOfBinding = [
+    //     "ProofOfBinding",
+    //     bstr,                  // Contains the SHA-256 of ProofOfProvisioning
+    //   ]
+    //
+    // Check that.
+    //
+    optional<vector<uint8_t>> proofOfBinding = support::certificateGetExtension(
+            signingKeyCertificate.encodedCertificate, "1.3.6.1.4.1.11129.2.1.26");
+    ASSERT_TRUE(proofOfBinding);
+    auto [item, _, message] = cppbor::parse(proofOfBinding.value());
+    ASSERT_NE(item, nullptr) << message;
+    const cppbor::Array* arrayItem = item->asArray();
+    ASSERT_NE(arrayItem, nullptr);
+    ASSERT_EQ(arrayItem->size(), 2);
+    const cppbor::Tstr* strItem = (*arrayItem)[0]->asTstr();
+    ASSERT_NE(strItem, nullptr);
+    EXPECT_EQ(strItem->value(), "ProofOfBinding");
+    const cppbor::Bstr* popSha256Item = (*arrayItem)[1]->asBstr();
+    ASSERT_NE(popSha256Item, nullptr);
+    EXPECT_EQ(popSha256Item->value(), support::sha256(proofOfProvisioning.value()));
+}
+
+GTEST_ALLOW_UNINSTANTIATED_PARAMETERIZED_TEST(AuthenticationKeyTests);
+INSTANTIATE_TEST_SUITE_P(
+        Identity, AuthenticationKeyTests,
+        testing::ValuesIn(android::getAidlHalInstanceNames(IIdentityCredentialStore::descriptor)),
+        android::PrintInstanceNameToString);
+
+}  // namespace android::hardware::identity
diff --git a/identity/aidl/vts/DeleteCredentialTests.cpp b/identity/aidl/vts/DeleteCredentialTests.cpp
new file mode 100644
index 0000000..1d30067
--- /dev/null
+++ b/identity/aidl/vts/DeleteCredentialTests.cpp
@@ -0,0 +1,169 @@
+/*
+ * Copyright (C) 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#define LOG_TAG "DeleteCredentialTests"
+
+#include <aidl/Gtest.h>
+#include <aidl/Vintf.h>
+#include <aidl/android/hardware/keymaster/HardwareAuthToken.h>
+#include <aidl/android/hardware/keymaster/VerificationToken.h>
+#include <android-base/logging.h>
+#include <android/hardware/identity/IIdentityCredentialStore.h>
+#include <android/hardware/identity/support/IdentityCredentialSupport.h>
+#include <binder/IServiceManager.h>
+#include <binder/ProcessState.h>
+#include <cppbor.h>
+#include <cppbor_parse.h>
+#include <gtest/gtest.h>
+#include <future>
+#include <map>
+#include <utility>
+
+#include "Util.h"
+
+namespace android::hardware::identity {
+
+using std::endl;
+using std::make_pair;
+using std::map;
+using std::optional;
+using std::pair;
+using std::string;
+using std::tie;
+using std::vector;
+
+using ::android::sp;
+using ::android::String16;
+using ::android::binder::Status;
+
+using ::android::hardware::keymaster::HardwareAuthToken;
+using ::android::hardware::keymaster::VerificationToken;
+
+class DeleteCredentialTests : public testing::TestWithParam<string> {
+  public:
+    virtual void SetUp() override {
+        credentialStore_ = android::waitForDeclaredService<IIdentityCredentialStore>(
+                String16(GetParam().c_str()));
+        ASSERT_NE(credentialStore_, nullptr);
+        halApiVersion_ = credentialStore_->getInterfaceVersion();
+    }
+
+    void provisionData();
+
+    // Set by provisionData
+    vector<uint8_t> credentialData_;
+    vector<uint8_t> credentialPubKey_;
+
+    sp<IIdentityCredentialStore> credentialStore_;
+    int halApiVersion_;
+};
+
+void DeleteCredentialTests::provisionData() {
+    string docType = "org.iso.18013-5.2019.mdl";
+    bool testCredential = true;
+    sp<IWritableIdentityCredential> wc;
+    ASSERT_TRUE(credentialStore_->createCredential(docType, testCredential, &wc).isOk());
+
+    vector<uint8_t> attestationApplicationId = {};
+    vector<uint8_t> attestationChallenge = {1};
+    vector<Certificate> certChain;
+    ASSERT_TRUE(wc->getAttestationCertificate(attestationApplicationId, attestationChallenge,
+                                              &certChain)
+                        .isOk());
+
+    optional<vector<uint8_t>> optCredentialPubKey =
+            support::certificateChainGetTopMostKey(certChain[0].encodedCertificate);
+    ASSERT_TRUE(optCredentialPubKey);
+    credentialPubKey_ = optCredentialPubKey.value();
+
+    size_t proofOfProvisioningSize = 106;
+    // Not in v1 HAL, may fail
+    wc->setExpectedProofOfProvisioningSize(proofOfProvisioningSize);
+
+    ASSERT_TRUE(wc->startPersonalization(1 /* numAccessControlProfiles */,
+                                         {1} /* numDataElementsPerNamespace */)
+                        .isOk());
+
+    // Access control profile 0: open access - don't care about the returned SACP
+    SecureAccessControlProfile sacp;
+    ASSERT_TRUE(wc->addAccessControlProfile(1, {}, false, 0, 0, &sacp).isOk());
+
+    // Single entry - don't care about the returned encrypted data
+    ASSERT_TRUE(wc->beginAddEntry({0}, "ns", "Some Data", 1).isOk());
+    vector<uint8_t> encryptedData;
+    ASSERT_TRUE(wc->addEntryValue({9}, &encryptedData).isOk());
+
+    vector<uint8_t> proofOfProvisioningSignature;
+    Status status = wc->finishAddingEntries(&credentialData_, &proofOfProvisioningSignature);
+    EXPECT_TRUE(status.isOk()) << status.exceptionCode() << ": " << status.exceptionMessage();
+}
+
+TEST_P(DeleteCredentialTests, Delete) {
+    provisionData();
+
+    sp<IIdentityCredential> credential;
+    ASSERT_TRUE(credentialStore_
+                        ->getCredential(
+                                CipherSuite::CIPHERSUITE_ECDHE_HKDF_ECDSA_WITH_AES_256_GCM_SHA256,
+                                credentialData_, &credential)
+                        .isOk());
+
+    vector<uint8_t> proofOfDeletionSignature;
+    ASSERT_TRUE(credential->deleteCredential(&proofOfDeletionSignature).isOk());
+    optional<vector<uint8_t>> proofOfDeletion =
+            support::coseSignGetPayload(proofOfDeletionSignature);
+    ASSERT_TRUE(proofOfDeletion);
+    string cborPretty = support::cborPrettyPrint(proofOfDeletion.value(), 32, {});
+    EXPECT_EQ("['ProofOfDeletion', 'org.iso.18013-5.2019.mdl', true, ]", cborPretty);
+    EXPECT_TRUE(support::coseCheckEcDsaSignature(proofOfDeletionSignature, {},  // Additional data
+                                                 credentialPubKey_));
+}
+
+TEST_P(DeleteCredentialTests, DeleteWithChallenge) {
+    if (halApiVersion_ < 3) {
+        GTEST_SKIP() << "Need HAL API version 3, have " << halApiVersion_;
+    }
+
+    provisionData();
+
+    sp<IIdentityCredential> credential;
+    ASSERT_TRUE(credentialStore_
+                        ->getCredential(
+                                CipherSuite::CIPHERSUITE_ECDHE_HKDF_ECDSA_WITH_AES_256_GCM_SHA256,
+                                credentialData_, &credential)
+                        .isOk());
+
+    vector<uint8_t> challenge = {65, 66, 67};
+    vector<uint8_t> proofOfDeletionSignature;
+    ASSERT_TRUE(
+            credential->deleteCredentialWithChallenge(challenge, &proofOfDeletionSignature).isOk());
+    optional<vector<uint8_t>> proofOfDeletion =
+            support::coseSignGetPayload(proofOfDeletionSignature);
+    ASSERT_TRUE(proofOfDeletion);
+    string cborPretty = support::cborPrettyPrint(proofOfDeletion.value(), 32, {});
+    EXPECT_EQ("['ProofOfDeletion', 'org.iso.18013-5.2019.mdl', {0x41, 0x42, 0x43}, true, ]",
+              cborPretty);
+    EXPECT_TRUE(support::coseCheckEcDsaSignature(proofOfDeletionSignature, {},  // Additional data
+                                                 credentialPubKey_));
+}
+
+GTEST_ALLOW_UNINSTANTIATED_PARAMETERIZED_TEST(DeleteCredentialTests);
+INSTANTIATE_TEST_SUITE_P(
+        Identity, DeleteCredentialTests,
+        testing::ValuesIn(android::getAidlHalInstanceNames(IIdentityCredentialStore::descriptor)),
+        android::PrintInstanceNameToString);
+
+}  // namespace android::hardware::identity
diff --git a/identity/aidl/vts/VtsHalIdentityEndToEndTest.cpp b/identity/aidl/vts/EndToEndTests.cpp
similarity index 93%
rename from identity/aidl/vts/VtsHalIdentityEndToEndTest.cpp
rename to identity/aidl/vts/EndToEndTests.cpp
index cdecb97..5798b4c 100644
--- a/identity/aidl/vts/VtsHalIdentityEndToEndTest.cpp
+++ b/identity/aidl/vts/EndToEndTests.cpp
@@ -29,7 +29,7 @@
 #include <map>
 #include <tuple>
 
-#include "VtsIdentityTestUtils.h"
+#include "Util.h"
 
 namespace android::hardware::identity {
 
@@ -50,18 +50,20 @@
 
 using test_utils::validateAttestationCertificate;
 
-class IdentityAidl : public testing::TestWithParam<std::string> {
+class EndToEndTests : public testing::TestWithParam<std::string> {
   public:
     virtual void SetUp() override {
         credentialStore_ = android::waitForDeclaredService<IIdentityCredentialStore>(
                 String16(GetParam().c_str()));
         ASSERT_NE(credentialStore_, nullptr);
+        halApiVersion_ = credentialStore_->getInterfaceVersion();
     }
 
     sp<IIdentityCredentialStore> credentialStore_;
+    int halApiVersion_;
 };
 
-TEST_P(IdentityAidl, hardwareInformation) {
+TEST_P(EndToEndTests, hardwareInformation) {
     HardwareInformation info;
     ASSERT_TRUE(credentialStore_->getHardwareInformation(&info).isOk());
     ASSERT_GT(info.credentialStoreName.size(), 0);
@@ -69,20 +71,21 @@
     ASSERT_GE(info.dataChunkSize, 256);
 }
 
-tuple<bool, string, vector<uint8_t>, vector<uint8_t>> extractFromTestCredentialData(
-        const vector<uint8_t>& credentialData) {
+tuple<bool, string, vector<uint8_t>, vector<uint8_t>, vector<uint8_t>>
+extractFromTestCredentialData(const vector<uint8_t>& credentialData) {
     string docType;
     vector<uint8_t> storageKey;
     vector<uint8_t> credentialPrivKey;
+    vector<uint8_t> sha256Pop;
 
     auto [item, _, message] = cppbor::parse(credentialData);
     if (item == nullptr) {
-        return make_tuple(false, docType, storageKey, credentialPrivKey);
+        return make_tuple(false, docType, storageKey, credentialPrivKey, sha256Pop);
     }
 
     const cppbor::Array* arrayItem = item->asArray();
     if (arrayItem == nullptr || arrayItem->size() != 3) {
-        return make_tuple(false, docType, storageKey, credentialPrivKey);
+        return make_tuple(false, docType, storageKey, credentialPrivKey, sha256Pop);
     }
 
     const cppbor::Tstr* docTypeItem = (*arrayItem)[0]->asTstr();
@@ -92,7 +95,7 @@
     const cppbor::Bstr* encryptedCredentialKeysItem = (*arrayItem)[2]->asBstr();
     if (docTypeItem == nullptr || testCredentialItem == nullptr ||
         encryptedCredentialKeysItem == nullptr) {
-        return make_tuple(false, docType, storageKey, credentialPrivKey);
+        return make_tuple(false, docType, storageKey, credentialPrivKey, sha256Pop);
     }
 
     docType = docTypeItem->value();
@@ -103,28 +106,38 @@
     optional<vector<uint8_t>> decryptedCredentialKeys =
             support::decryptAes128Gcm(hardwareBoundKey, encryptedCredentialKeys, docTypeVec);
     if (!decryptedCredentialKeys) {
-        return make_tuple(false, docType, storageKey, credentialPrivKey);
+        return make_tuple(false, docType, storageKey, credentialPrivKey, sha256Pop);
     }
 
     auto [dckItem, dckPos, dckMessage] = cppbor::parse(decryptedCredentialKeys.value());
     if (dckItem == nullptr) {
-        return make_tuple(false, docType, storageKey, credentialPrivKey);
+        return make_tuple(false, docType, storageKey, credentialPrivKey, sha256Pop);
     }
     const cppbor::Array* dckArrayItem = dckItem->asArray();
-    if (dckArrayItem == nullptr || dckArrayItem->size() != 2) {
-        return make_tuple(false, docType, storageKey, credentialPrivKey);
+    if (dckArrayItem == nullptr) {
+        return make_tuple(false, docType, storageKey, credentialPrivKey, sha256Pop);
+    }
+    if (dckArrayItem->size() < 2) {
+        return make_tuple(false, docType, storageKey, credentialPrivKey, sha256Pop);
     }
     const cppbor::Bstr* storageKeyItem = (*dckArrayItem)[0]->asBstr();
     const cppbor::Bstr* credentialPrivKeyItem = (*dckArrayItem)[1]->asBstr();
     if (storageKeyItem == nullptr || credentialPrivKeyItem == nullptr) {
-        return make_tuple(false, docType, storageKey, credentialPrivKey);
+        return make_tuple(false, docType, storageKey, credentialPrivKey, sha256Pop);
     }
     storageKey = storageKeyItem->value();
     credentialPrivKey = credentialPrivKeyItem->value();
-    return make_tuple(true, docType, storageKey, credentialPrivKey);
+    if (dckArrayItem->size() == 3) {
+        const cppbor::Bstr* sha256PopItem = (*dckArrayItem)[2]->asBstr();
+        if (sha256PopItem == nullptr) {
+            return make_tuple(false, docType, storageKey, credentialPrivKey, sha256Pop);
+        }
+        sha256Pop = sha256PopItem->value();
+    }
+    return make_tuple(true, docType, storageKey, credentialPrivKey, sha256Pop);
 }
 
-TEST_P(IdentityAidl, createAndRetrieveCredential) {
+TEST_P(EndToEndTests, createAndRetrieveCredential) {
     // First, generate a key-pair for the reader since its public key will be
     // part of the request data.
     vector<uint8_t> readerKey;
@@ -277,8 +290,9 @@
 
     // Extract doctype, storage key, and credentialPrivKey from credentialData... this works
     // only because we asked for a test-credential meaning that the HBK is all zeroes.
-    auto [exSuccess, exDocType, exStorageKey, exCredentialPrivKey] =
+    auto [exSuccess, exDocType, exStorageKey, exCredentialPrivKey, exSha256Pop] =
             extractFromTestCredentialData(credentialData);
+
     ASSERT_TRUE(exSuccess);
     ASSERT_EQ(exDocType, "org.iso.18013-5.2019.mdl");
     // ... check that the public key derived from the private key matches what was
@@ -291,6 +305,13 @@
     ASSERT_TRUE(exCredentialPubKey);
     ASSERT_EQ(exCredentialPubKey.value(), credentialPubKey.value());
 
+    // Starting with API version 3 (feature version 202101) we require SHA-256(ProofOfProvisioning)
+    // to be in CredentialKeys (which is stored encrypted in CredentialData). Check
+    // that it's there with the expected value.
+    if (halApiVersion_ >= 3) {
+        ASSERT_EQ(exSha256Pop, support::sha256(proofOfProvisioning.value()));
+    }
+
     // Now that the credential has been provisioned, read it back and check the
     // correct data is returned.
     sp<IIdentityCredential> credential;
@@ -498,13 +519,11 @@
     EXPECT_EQ(mac, calculatedMac);
 }
 
-GTEST_ALLOW_UNINSTANTIATED_PARAMETERIZED_TEST(IdentityAidl);
+GTEST_ALLOW_UNINSTANTIATED_PARAMETERIZED_TEST(EndToEndTests);
 INSTANTIATE_TEST_SUITE_P(
-        Identity, IdentityAidl,
+        Identity, EndToEndTests,
         testing::ValuesIn(android::getAidlHalInstanceNames(IIdentityCredentialStore::descriptor)),
         android::PrintInstanceNameToString);
-// INSTANTIATE_TEST_SUITE_P(Identity, IdentityAidl,
-// testing::Values("android.hardware.identity.IIdentityCredentialStore/default"));
 
 }  // namespace android::hardware::identity
 
diff --git a/identity/aidl/vts/ProveOwnershipTests.cpp b/identity/aidl/vts/ProveOwnershipTests.cpp
new file mode 100644
index 0000000..d1a3d39
--- /dev/null
+++ b/identity/aidl/vts/ProveOwnershipTests.cpp
@@ -0,0 +1,146 @@
+/*
+ * Copyright (C) 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#define LOG_TAG "ProveOwnershipTests"
+
+#include <aidl/Gtest.h>
+#include <aidl/Vintf.h>
+#include <aidl/android/hardware/keymaster/HardwareAuthToken.h>
+#include <aidl/android/hardware/keymaster/VerificationToken.h>
+#include <android-base/logging.h>
+#include <android/hardware/identity/IIdentityCredentialStore.h>
+#include <android/hardware/identity/support/IdentityCredentialSupport.h>
+#include <binder/IServiceManager.h>
+#include <binder/ProcessState.h>
+#include <cppbor.h>
+#include <cppbor_parse.h>
+#include <gtest/gtest.h>
+#include <future>
+#include <map>
+#include <utility>
+
+#include "Util.h"
+
+namespace android::hardware::identity {
+
+using std::endl;
+using std::make_pair;
+using std::map;
+using std::optional;
+using std::pair;
+using std::string;
+using std::tie;
+using std::vector;
+
+using ::android::sp;
+using ::android::String16;
+using ::android::binder::Status;
+
+using ::android::hardware::keymaster::HardwareAuthToken;
+using ::android::hardware::keymaster::VerificationToken;
+
+class ProveOwnershipTests : public testing::TestWithParam<string> {
+  public:
+    virtual void SetUp() override {
+        credentialStore_ = android::waitForDeclaredService<IIdentityCredentialStore>(
+                String16(GetParam().c_str()));
+        ASSERT_NE(credentialStore_, nullptr);
+        halApiVersion_ = credentialStore_->getInterfaceVersion();
+    }
+
+    void provisionData();
+
+    // Set by provisionData
+    vector<uint8_t> credentialData_;
+    vector<uint8_t> credentialPubKey_;
+
+    sp<IIdentityCredentialStore> credentialStore_;
+    int halApiVersion_;
+};
+
+void ProveOwnershipTests::provisionData() {
+    string docType = "org.iso.18013-5.2019.mdl";
+    bool testCredential = true;
+    sp<IWritableIdentityCredential> wc;
+    ASSERT_TRUE(credentialStore_->createCredential(docType, testCredential, &wc).isOk());
+
+    vector<uint8_t> attestationApplicationId = {};
+    vector<uint8_t> attestationChallenge = {1};
+    vector<Certificate> certChain;
+    ASSERT_TRUE(wc->getAttestationCertificate(attestationApplicationId, attestationChallenge,
+                                              &certChain)
+                        .isOk());
+
+    optional<vector<uint8_t>> optCredentialPubKey =
+            support::certificateChainGetTopMostKey(certChain[0].encodedCertificate);
+    ASSERT_TRUE(optCredentialPubKey);
+    credentialPubKey_ = optCredentialPubKey.value();
+
+    size_t proofOfProvisioningSize = 106;
+    // Not in v1 HAL, may fail
+    wc->setExpectedProofOfProvisioningSize(proofOfProvisioningSize);
+
+    ASSERT_TRUE(wc->startPersonalization(1 /* numAccessControlProfiles */,
+                                         {1} /* numDataElementsPerNamespace */)
+                        .isOk());
+
+    // Access control profile 0: open access - don't care about the returned SACP
+    SecureAccessControlProfile sacp;
+    ASSERT_TRUE(wc->addAccessControlProfile(1, {}, false, 0, 0, &sacp).isOk());
+
+    // Single entry - don't care about the returned encrypted data
+    ASSERT_TRUE(wc->beginAddEntry({0}, "ns", "Some Data", 1).isOk());
+    vector<uint8_t> encryptedData;
+    ASSERT_TRUE(wc->addEntryValue({9}, &encryptedData).isOk());
+
+    vector<uint8_t> proofOfProvisioningSignature;
+    Status status = wc->finishAddingEntries(&credentialData_, &proofOfProvisioningSignature);
+    EXPECT_TRUE(status.isOk()) << status.exceptionCode() << ": " << status.exceptionMessage();
+}
+
+TEST_P(ProveOwnershipTests, proveOwnership) {
+    if (halApiVersion_ < 3) {
+        GTEST_SKIP() << "Need HAL API version 3, have " << halApiVersion_;
+    }
+
+    provisionData();
+
+    sp<IIdentityCredential> credential;
+    ASSERT_TRUE(credentialStore_
+                        ->getCredential(
+                                CipherSuite::CIPHERSUITE_ECDHE_HKDF_ECDSA_WITH_AES_256_GCM_SHA256,
+                                credentialData_, &credential)
+                        .isOk());
+
+    vector<uint8_t> challenge = {17, 18};
+    vector<uint8_t> proofOfOwnershipSignature;
+    ASSERT_TRUE(credential->proveOwnership(challenge, &proofOfOwnershipSignature).isOk());
+    optional<vector<uint8_t>> proofOfOwnership =
+            support::coseSignGetPayload(proofOfOwnershipSignature);
+    ASSERT_TRUE(proofOfOwnership);
+    string cborPretty = support::cborPrettyPrint(proofOfOwnership.value(), 32, {});
+    EXPECT_EQ("['ProofOfOwnership', 'org.iso.18013-5.2019.mdl', {0x11, 0x12}, true, ]", cborPretty);
+    EXPECT_TRUE(support::coseCheckEcDsaSignature(proofOfOwnershipSignature, {},  // Additional data
+                                                 credentialPubKey_));
+}
+
+GTEST_ALLOW_UNINSTANTIATED_PARAMETERIZED_TEST(ProveOwnershipTests);
+INSTANTIATE_TEST_SUITE_P(
+        Identity, ProveOwnershipTests,
+        testing::ValuesIn(android::getAidlHalInstanceNames(IIdentityCredentialStore::descriptor)),
+        android::PrintInstanceNameToString);
+
+}  // namespace android::hardware::identity
diff --git a/identity/aidl/vts/ReaderAuthTests.cpp b/identity/aidl/vts/ReaderAuthTests.cpp
index 0a9fdc0..7656c8e 100644
--- a/identity/aidl/vts/ReaderAuthTests.cpp
+++ b/identity/aidl/vts/ReaderAuthTests.cpp
@@ -32,7 +32,7 @@
 #include <map>
 #include <utility>
 
-#include "VtsIdentityTestUtils.h"
+#include "Util.h"
 
 namespace android::hardware::identity {
 
@@ -123,9 +123,9 @@
                                    const vector<uint8_t>& signingKey) {
     time_t validityNotBefore = 0;
     time_t validityNotAfter = 0xffffffff;
-    optional<vector<uint8_t>> cert =
-            support::ecPublicKeyGenerateCertificate(publicKey, signingKey, "24601", "Issuer",
-                                                    "Subject", validityNotBefore, validityNotAfter);
+    optional<vector<uint8_t>> cert = support::ecPublicKeyGenerateCertificate(
+            publicKey, signingKey, "24601", "Issuer", "Subject", validityNotBefore,
+            validityNotAfter, {});
     return cert.value();
 }
 
diff --git a/identity/aidl/vts/TestCredentialTests.cpp b/identity/aidl/vts/TestCredentialTests.cpp
new file mode 100644
index 0000000..d53de3b
--- /dev/null
+++ b/identity/aidl/vts/TestCredentialTests.cpp
@@ -0,0 +1,204 @@
+/*
+ * Copyright (C) 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#define LOG_TAG "TestCredentialTests"
+
+#include <aidl/Gtest.h>
+#include <aidl/Vintf.h>
+#include <aidl/android/hardware/keymaster/HardwareAuthToken.h>
+#include <aidl/android/hardware/keymaster/VerificationToken.h>
+#include <android-base/logging.h>
+#include <android/hardware/identity/IIdentityCredentialStore.h>
+#include <android/hardware/identity/support/IdentityCredentialSupport.h>
+#include <binder/IServiceManager.h>
+#include <binder/ProcessState.h>
+#include <cppbor.h>
+#include <cppbor_parse.h>
+#include <gtest/gtest.h>
+#include <future>
+#include <map>
+#include <utility>
+
+#include "Util.h"
+
+namespace android::hardware::identity {
+
+using std::endl;
+using std::make_pair;
+using std::map;
+using std::optional;
+using std::pair;
+using std::string;
+using std::tie;
+using std::vector;
+
+using ::android::sp;
+using ::android::String16;
+using ::android::binder::Status;
+
+using ::android::hardware::keymaster::HardwareAuthToken;
+using ::android::hardware::keymaster::VerificationToken;
+
+class TestCredentialTests : public testing::TestWithParam<string> {
+  public:
+    virtual void SetUp() override {
+        string halInstanceName = GetParam();
+        credentialStore_ = android::waitForDeclaredService<IIdentityCredentialStore>(
+                String16(halInstanceName.c_str()));
+        ASSERT_NE(credentialStore_, nullptr);
+        halApiVersion_ = credentialStore_->getInterfaceVersion();
+    }
+
+    sp<IIdentityCredentialStore> credentialStore_;
+    int halApiVersion_;
+};
+
+TEST_P(TestCredentialTests, testCredential) {
+    string docType = "org.iso.18013-5.2019.mdl";
+    sp<IWritableIdentityCredential> wc;
+    ASSERT_TRUE(credentialStore_
+                        ->createCredential(docType,
+                                           true,  // testCredential
+                                           &wc)
+                        .isOk());
+
+    vector<uint8_t> attestationApplicationId = {};
+    vector<uint8_t> attestationChallenge = {1};
+    vector<Certificate> certChain;
+    ASSERT_TRUE(wc->getAttestationCertificate(attestationApplicationId, attestationChallenge,
+                                              &certChain)
+                        .isOk());
+
+    optional<vector<uint8_t>> optCredentialPubKey =
+            support::certificateChainGetTopMostKey(certChain[0].encodedCertificate);
+    ASSERT_TRUE(optCredentialPubKey);
+    vector<uint8_t> credentialPubKey;
+    credentialPubKey = optCredentialPubKey.value();
+
+    size_t proofOfProvisioningSize = 112;
+    // Not in v1 HAL, may fail
+    wc->setExpectedProofOfProvisioningSize(proofOfProvisioningSize);
+
+    ASSERT_TRUE(wc->startPersonalization(1 /* numAccessControlProfiles */,
+                                         {1} /* numDataElementsPerNamespace */)
+                        .isOk());
+
+    // Access control profile 0: open access - don't care about the returned SACP
+    SecureAccessControlProfile sacp;
+    ASSERT_TRUE(wc->addAccessControlProfile(1, {}, false, 0, 0, &sacp).isOk());
+
+    // Single entry - don't care about the returned encrypted data
+    vector<uint8_t> encryptedData;
+    vector<uint8_t> tstrLastName = cppbor::Tstr("Turing").encode();
+    ASSERT_TRUE(wc->beginAddEntry({1}, "ns", "Last name", tstrLastName.size()).isOk());
+    ASSERT_TRUE(wc->addEntryValue(tstrLastName, &encryptedData).isOk());
+
+    vector<uint8_t> proofOfProvisioningSignature;
+    vector<uint8_t> credentialData;
+    Status status = wc->finishAddingEntries(&credentialData, &proofOfProvisioningSignature);
+    EXPECT_TRUE(status.isOk()) << status.exceptionCode() << ": " << status.exceptionMessage();
+
+    optional<vector<uint8_t>> proofOfProvisioning =
+            support::coseSignGetPayload(proofOfProvisioningSignature);
+    ASSERT_TRUE(proofOfProvisioning);
+    string cborPretty = support::cborPrettyPrint(proofOfProvisioning.value(), 32, {});
+    EXPECT_EQ(
+            "[\n"
+            "  'ProofOfProvisioning',\n"
+            "  'org.iso.18013-5.2019.mdl',\n"
+            "  [\n"
+            "    {\n"
+            "      'id' : 1,\n"
+            "    },\n"
+            "  ],\n"
+            "  {\n"
+            "    'ns' : [\n"
+            "      {\n"
+            "        'name' : 'Last name',\n"
+            "        'value' : 'Turing',\n"
+            "        'accessControlProfiles' : [1, ],\n"
+            "      },\n"
+            "    ],\n"
+            "  },\n"
+            "  true,\n"
+            "]",
+            cborPretty);
+    // Make sure it's signed by the CredentialKey in the returned cert chain.
+    EXPECT_TRUE(support::coseCheckEcDsaSignature(proofOfProvisioningSignature,
+                                                 {},  // Additional data
+                                                 credentialPubKey));
+
+    // Now analyze credentialData..
+    auto [item, _, message] = cppbor::parse(credentialData);
+    ASSERT_NE(item, nullptr);
+    const cppbor::Array* arrayItem = item->asArray();
+    ASSERT_NE(arrayItem, nullptr);
+    ASSERT_EQ(arrayItem->size(), 3);
+    const cppbor::Tstr* docTypeItem = (*arrayItem)[0]->asTstr();
+    const cppbor::Bool* testCredentialItem =
+            ((*arrayItem)[1]->asSimple() != nullptr ? ((*arrayItem)[1]->asSimple()->asBool())
+                                                    : nullptr);
+    EXPECT_EQ(docTypeItem->value(), docType);
+    EXPECT_EQ(testCredentialItem->value(), true);
+
+    vector<uint8_t> hardwareBoundKey = support::getTestHardwareBoundKey();
+    const cppbor::Bstr* encryptedCredentialKeysItem = (*arrayItem)[2]->asBstr();
+    const vector<uint8_t>& encryptedCredentialKeys = encryptedCredentialKeysItem->value();
+    const vector<uint8_t> docTypeVec(docType.begin(), docType.end());
+    optional<vector<uint8_t>> decryptedCredentialKeys =
+            support::decryptAes128Gcm(hardwareBoundKey, encryptedCredentialKeys, docTypeVec);
+    ASSERT_TRUE(decryptedCredentialKeys);
+    auto [dckItem, dckPos, dckMessage] = cppbor::parse(decryptedCredentialKeys.value());
+    ASSERT_NE(dckItem, nullptr) << dckMessage;
+    const cppbor::Array* dckArrayItem = dckItem->asArray();
+    ASSERT_NE(dckArrayItem, nullptr);
+    // In HAL API version 1 and 2 this array has two items, in version 3 and later it has three.
+    if (halApiVersion_ < 3) {
+        ASSERT_EQ(dckArrayItem->size(), 2);
+    } else {
+        ASSERT_EQ(dckArrayItem->size(), 3);
+    }
+    const cppbor::Bstr* storageKeyItem = (*dckArrayItem)[0]->asBstr();
+    const vector<uint8_t> storageKey = storageKeyItem->value();
+    // const cppbor::Bstr* credentialPrivKeyItem = (*dckArrayItem)[1]->asBstr();
+    // const vector<uint8_t> credentialPrivKey = credentialPrivKeyItem->value();
+
+    // Check storageKey can be used to decrypt |encryptedData| to |tstrLastName|
+    vector<uint8_t> additionalData = cppbor::Map()
+                                             .add("Namespace", "ns")
+                                             .add("Name", "Last name")
+                                             .add("AccessControlProfileIds", cppbor::Array().add(1))
+                                             .encode();
+    optional<vector<uint8_t>> decryptedDataItemValue =
+            support::decryptAes128Gcm(storageKey, encryptedData, additionalData);
+    ASSERT_TRUE(decryptedDataItemValue);
+    EXPECT_EQ(decryptedDataItemValue.value(), tstrLastName);
+
+    // Check that SHA-256(ProofOfProvisioning) matches (only in HAL API version 3)
+    if (halApiVersion_ >= 3) {
+        const cppbor::Bstr* popSha256Item = (*dckArrayItem)[2]->asBstr();
+        const vector<uint8_t> popSha256 = popSha256Item->value();
+        ASSERT_EQ(popSha256, support::sha256(proofOfProvisioning.value()));
+    }
+}
+
+GTEST_ALLOW_UNINSTANTIATED_PARAMETERIZED_TEST(TestCredentialTests);
+INSTANTIATE_TEST_SUITE_P(
+        Identity, TestCredentialTests,
+        testing::ValuesIn(android::getAidlHalInstanceNames(IIdentityCredentialStore::descriptor)),
+        android::PrintInstanceNameToString);
+
+}  // namespace android::hardware::identity
diff --git a/identity/aidl/vts/UpdateCredentialTests.cpp b/identity/aidl/vts/UpdateCredentialTests.cpp
new file mode 100644
index 0000000..9c5ca55
--- /dev/null
+++ b/identity/aidl/vts/UpdateCredentialTests.cpp
@@ -0,0 +1,232 @@
+/*
+ * Copyright (C) 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#define LOG_TAG "UpdateCredentialTests"
+
+#include <aidl/Gtest.h>
+#include <aidl/Vintf.h>
+#include <aidl/android/hardware/keymaster/HardwareAuthToken.h>
+#include <aidl/android/hardware/keymaster/VerificationToken.h>
+#include <android-base/logging.h>
+#include <android/hardware/identity/IIdentityCredentialStore.h>
+#include <android/hardware/identity/support/IdentityCredentialSupport.h>
+#include <binder/IServiceManager.h>
+#include <binder/ProcessState.h>
+#include <cppbor.h>
+#include <cppbor_parse.h>
+#include <gtest/gtest.h>
+#include <future>
+#include <map>
+#include <utility>
+
+#include "Util.h"
+
+namespace android::hardware::identity {
+
+using std::endl;
+using std::make_pair;
+using std::map;
+using std::optional;
+using std::pair;
+using std::string;
+using std::tie;
+using std::vector;
+
+using ::android::sp;
+using ::android::String16;
+using ::android::binder::Status;
+
+using ::android::hardware::keymaster::HardwareAuthToken;
+using ::android::hardware::keymaster::VerificationToken;
+
+class UpdateCredentialTests : public testing::TestWithParam<string> {
+  public:
+    virtual void SetUp() override {
+        credentialStore_ = android::waitForDeclaredService<IIdentityCredentialStore>(
+                String16(GetParam().c_str()));
+        ASSERT_NE(credentialStore_, nullptr);
+        halApiVersion_ = credentialStore_->getInterfaceVersion();
+    }
+
+    void provisionData();
+
+    // Set by provisionData
+    vector<uint8_t> credentialData_;
+    vector<uint8_t> credentialPubKey_;
+
+    sp<IIdentityCredentialStore> credentialStore_;
+    int halApiVersion_;
+};
+
+void UpdateCredentialTests::provisionData() {
+    string docType = "org.iso.18013-5.2019.mdl";
+    bool testCredential = true;
+    sp<IWritableIdentityCredential> wc;
+    ASSERT_TRUE(credentialStore_->createCredential(docType, testCredential, &wc).isOk());
+
+    vector<uint8_t> attestationApplicationId = {};
+    vector<uint8_t> attestationChallenge = {1};
+    vector<Certificate> certChain;
+    ASSERT_TRUE(wc->getAttestationCertificate(attestationApplicationId, attestationChallenge,
+                                              &certChain)
+                        .isOk());
+
+    optional<vector<uint8_t>> optCredentialPubKey =
+            support::certificateChainGetTopMostKey(certChain[0].encodedCertificate);
+    ASSERT_TRUE(optCredentialPubKey);
+    credentialPubKey_ = optCredentialPubKey.value();
+
+    size_t proofOfProvisioningSize = 112;
+    // Not in v1 HAL, may fail
+    wc->setExpectedProofOfProvisioningSize(proofOfProvisioningSize);
+
+    ASSERT_TRUE(wc->startPersonalization(1 /* numAccessControlProfiles */,
+                                         {1} /* numDataElementsPerNamespace */)
+                        .isOk());
+
+    // Access control profile 0: open access - don't care about the returned SACP
+    SecureAccessControlProfile sacp;
+    ASSERT_TRUE(wc->addAccessControlProfile(1, {}, false, 0, 0, &sacp).isOk());
+
+    // Single entry - don't care about the returned encrypted data
+    vector<uint8_t> encryptedData;
+    vector<uint8_t> tstrLastName = cppbor::Tstr("Prince").encode();
+    ASSERT_TRUE(wc->beginAddEntry({1}, "ns", "Last name", tstrLastName.size()).isOk());
+    ASSERT_TRUE(wc->addEntryValue(tstrLastName, &encryptedData).isOk());
+
+    vector<uint8_t> proofOfProvisioningSignature;
+    Status status = wc->finishAddingEntries(&credentialData_, &proofOfProvisioningSignature);
+    EXPECT_TRUE(status.isOk()) << status.exceptionCode() << ": " << status.exceptionMessage();
+
+    optional<vector<uint8_t>> proofOfProvisioning =
+            support::coseSignGetPayload(proofOfProvisioningSignature);
+    ASSERT_TRUE(proofOfProvisioning);
+    string cborPretty = support::cborPrettyPrint(proofOfProvisioning.value(), 32, {});
+    EXPECT_EQ(
+            "[\n"
+            "  'ProofOfProvisioning',\n"
+            "  'org.iso.18013-5.2019.mdl',\n"
+            "  [\n"
+            "    {\n"
+            "      'id' : 1,\n"
+            "    },\n"
+            "  ],\n"
+            "  {\n"
+            "    'ns' : [\n"
+            "      {\n"
+            "        'name' : 'Last name',\n"
+            "        'value' : 'Prince',\n"
+            "        'accessControlProfiles' : [1, ],\n"
+            "      },\n"
+            "    ],\n"
+            "  },\n"
+            "  true,\n"
+            "]",
+            cborPretty);
+    // Make sure it's signed by the CredentialKey in the returned cert chain.
+    EXPECT_TRUE(support::coseCheckEcDsaSignature(proofOfProvisioningSignature,
+                                                 {},  // Additional data
+                                                 credentialPubKey_));
+}
+
+TEST_P(UpdateCredentialTests, updateCredential) {
+    if (halApiVersion_ < 3) {
+        GTEST_SKIP() << "Need HAL API version 3, have " << halApiVersion_;
+    }
+
+    provisionData();
+
+    sp<IIdentityCredential> credential;
+    ASSERT_TRUE(credentialStore_
+                        ->getCredential(
+                                CipherSuite::CIPHERSUITE_ECDHE_HKDF_ECDSA_WITH_AES_256_GCM_SHA256,
+                                credentialData_, &credential)
+                        .isOk());
+
+    sp<IWritableIdentityCredential> wc;
+    ASSERT_TRUE(credential->updateCredential(&wc).isOk());
+
+    // Getting an attestation cert should fail (because it's an update).
+    vector<uint8_t> attestationApplicationId = {};
+    vector<uint8_t> attestationChallenge = {1};
+    vector<Certificate> certChain;
+    Status result = wc->getAttestationCertificate(attestationApplicationId, attestationChallenge,
+                                                  &certChain);
+    ASSERT_FALSE(result.isOk());
+    EXPECT_EQ(binder::Status::EX_SERVICE_SPECIFIC, result.exceptionCode());
+    EXPECT_EQ(IIdentityCredentialStore::STATUS_FAILED, result.serviceSpecificErrorCode());
+
+    // Now provision some new data...
+    //
+    size_t proofOfProvisioningSize = 117;
+    // Not in v1 HAL, may fail
+    wc->setExpectedProofOfProvisioningSize(proofOfProvisioningSize);
+
+    ASSERT_TRUE(wc->startPersonalization(1 /* numAccessControlProfiles */,
+                                         {1} /* numDataElementsPerNamespace */)
+                        .isOk());
+
+    // Access control profile 0: open access - don't care about the returned SACP
+    SecureAccessControlProfile sacp;
+    ASSERT_TRUE(wc->addAccessControlProfile(2, {}, false, 0, 0, &sacp).isOk());
+
+    // Single entry - don't care about the returned encrypted data
+    vector<uint8_t> encryptedData;
+    vector<uint8_t> tstrLastName = cppbor::Tstr("T.A.F.K.A.P").encode();
+    ASSERT_TRUE(wc->beginAddEntry({2}, "ns", "Last name", tstrLastName.size()).isOk());
+    ASSERT_TRUE(wc->addEntryValue(tstrLastName, &encryptedData).isOk());
+
+    vector<uint8_t> proofOfProvisioningSignature;
+    Status status = wc->finishAddingEntries(&credentialData_, &proofOfProvisioningSignature);
+    EXPECT_TRUE(status.isOk()) << status.exceptionCode() << ": " << status.exceptionMessage();
+    optional<vector<uint8_t>> proofOfProvisioning =
+            support::coseSignGetPayload(proofOfProvisioningSignature);
+    ASSERT_TRUE(proofOfProvisioning);
+    string cborPretty = support::cborPrettyPrint(proofOfProvisioning.value(), 32, {});
+    EXPECT_EQ(
+            "[\n"
+            "  'ProofOfProvisioning',\n"
+            "  'org.iso.18013-5.2019.mdl',\n"
+            "  [\n"
+            "    {\n"
+            "      'id' : 2,\n"
+            "    },\n"
+            "  ],\n"
+            "  {\n"
+            "    'ns' : [\n"
+            "      {\n"
+            "        'name' : 'Last name',\n"
+            "        'value' : 'T.A.F.K.A.P',\n"
+            "        'accessControlProfiles' : [2, ],\n"
+            "      },\n"
+            "    ],\n"
+            "  },\n"
+            "  true,\n"
+            "]",
+            cborPretty);
+    // Make sure it's signed by the same CredentialKey we originally provisioned with.
+    EXPECT_TRUE(support::coseCheckEcDsaSignature(proofOfProvisioningSignature,
+                                                 {},  // Additional data
+                                                 credentialPubKey_));
+}
+
+GTEST_ALLOW_UNINSTANTIATED_PARAMETERIZED_TEST(UpdateCredentialTests);
+INSTANTIATE_TEST_SUITE_P(
+        Identity, UpdateCredentialTests,
+        testing::ValuesIn(android::getAidlHalInstanceNames(IIdentityCredentialStore::descriptor)),
+        android::PrintInstanceNameToString);
+
+}  // namespace android::hardware::identity
diff --git a/identity/aidl/vts/UserAuthTests.cpp b/identity/aidl/vts/UserAuthTests.cpp
index 327493c..ef89d1c 100644
--- a/identity/aidl/vts/UserAuthTests.cpp
+++ b/identity/aidl/vts/UserAuthTests.cpp
@@ -32,7 +32,7 @@
 #include <map>
 #include <utility>
 
-#include "VtsIdentityTestUtils.h"
+#include "Util.h"
 
 namespace android::hardware::identity {
 
@@ -145,7 +145,7 @@
     EXPECT_TRUE(status.isOk()) << status.exceptionCode() << ": " << status.exceptionMessage();
 }
 
-// From ReaderAuthTest.cpp - TODO: consolidate with VtsIdentityTestUtils.h
+// From ReaderAuthTest.cpp - TODO: consolidate with Util.h
 pair<vector<uint8_t>, vector<uint8_t>> generateReaderKey();
 vector<uint8_t> generateReaderCert(const vector<uint8_t>& publicKey,
                                    const vector<uint8_t>& signingKey);
diff --git a/identity/aidl/vts/VtsIdentityTestUtils.cpp b/identity/aidl/vts/Util.cpp
similarity index 98%
rename from identity/aidl/vts/VtsIdentityTestUtils.cpp
rename to identity/aidl/vts/Util.cpp
index 3b10651..1148cb0 100644
--- a/identity/aidl/vts/VtsIdentityTestUtils.cpp
+++ b/identity/aidl/vts/Util.cpp
@@ -14,15 +14,18 @@
  * limitations under the License.
  */
 
-#define LOG_TAG "VtsIdentityTestUtils"
+#define LOG_TAG "Util"
 
-#include "VtsIdentityTestUtils.h"
+#include "Util.h"
+
+#include <android-base/logging.h>
 
 #include <aidl/Gtest.h>
-#include <android-base/logging.h>
+#include <android-base/stringprintf.h>
 #include <keymaster/km_openssl/openssl_utils.h>
 #include <keymasterV4_1/attestation_record.h>
 #include <charconv>
+
 #include <map>
 
 namespace android::hardware::identity::test_utils {
@@ -35,6 +38,7 @@
 
 using ::android::sp;
 using ::android::String16;
+using ::android::base::StringPrintf;
 using ::android::binder::Status;
 using ::keymaster::X509_Ptr;
 
@@ -86,7 +90,7 @@
 
     return support::ecPublicKeyGenerateCertificate(readerPublicKey.value(), readerKey.value(),
                                                    serialDecimal, issuer, subject,
-                                                   validityNotBefore, validityNotAfter);
+                                                   validityNotBefore, validityNotAfter, {});
 }
 
 optional<vector<SecureAccessControlProfile>> addAccessControlProfiles(
diff --git a/identity/aidl/vts/VtsIdentityTestUtils.h b/identity/aidl/vts/Util.h
similarity index 99%
rename from identity/aidl/vts/VtsIdentityTestUtils.h
rename to identity/aidl/vts/Util.h
index 85c24f8..80e52a2 100644
--- a/identity/aidl/vts/VtsIdentityTestUtils.h
+++ b/identity/aidl/vts/Util.h
@@ -21,6 +21,7 @@
 #include <android/hardware/identity/support/IdentityCredentialSupport.h>
 #include <cppbor.h>
 #include <cppbor_parse.h>
+#include <gtest/gtest.h>
 
 namespace android::hardware::identity::test_utils {
 
diff --git a/identity/aidl/vts/VtsAttestationTests.cpp b/identity/aidl/vts/VtsAttestationTests.cpp
index 5529853..e12fe05 100644
--- a/identity/aidl/vts/VtsAttestationTests.cpp
+++ b/identity/aidl/vts/VtsAttestationTests.cpp
@@ -29,7 +29,7 @@
 #include <future>
 #include <map>
 
-#include "VtsIdentityTestUtils.h"
+#include "Util.h"
 
 namespace android::hardware::identity {
 
diff --git a/identity/aidl/vts/VtsIWritableIdentityCredentialTests.cpp b/identity/aidl/vts/VtsIWritableIdentityCredentialTests.cpp
index 1629a0c..cc63c48 100644
--- a/identity/aidl/vts/VtsIWritableIdentityCredentialTests.cpp
+++ b/identity/aidl/vts/VtsIWritableIdentityCredentialTests.cpp
@@ -29,7 +29,7 @@
 #include <future>
 #include <map>
 
-#include "VtsIdentityTestUtils.h"
+#include "Util.h"
 
 namespace android::hardware::identity {
 
diff --git a/identity/support/include/android/hardware/identity/support/IdentityCredentialSupport.h b/identity/support/include/android/hardware/identity/support/IdentityCredentialSupport.h
index 3aa5bb6..3b91de6 100644
--- a/identity/support/include/android/hardware/identity/support/IdentityCredentialSupport.h
+++ b/identity/support/include/android/hardware/identity/support/IdentityCredentialSupport.h
@@ -18,6 +18,7 @@
 #define IDENTITY_SUPPORT_INCLUDE_IDENTITY_CREDENTIAL_UTILS_H_
 
 #include <cstdint>
+#include <map>
 #include <optional>
 #include <string>
 #include <tuple>
@@ -29,11 +30,12 @@
 namespace identity {
 namespace support {
 
+using ::std::map;
 using ::std::optional;
+using ::std::pair;
 using ::std::string;
 using ::std::tuple;
 using ::std::vector;
-using ::std::pair;
 
 // The semantic tag for a bstr which includes Encoded CBOR (RFC 7049, section 2.4)
 const int kSemanticTagEncodedCbor = 24;
@@ -221,6 +223,11 @@
 //
 optional<pair<time_t, time_t>> certificateGetValidity(const vector<uint8_t>& x509Certificate);
 
+// Looks for an extension with OID in |oidStr| which must be an stored as an OCTET STRING.
+//
+optional<vector<uint8_t>> certificateGetExtension(const vector<uint8_t>& x509Certificate,
+                                                  const string& oidStr);
+
 // Generates a X.509 certificate for |publicKey| (which must be in the format
 // returned by ecKeyPairGetPublicKey()).
 //
@@ -230,7 +237,8 @@
 optional<vector<uint8_t>> ecPublicKeyGenerateCertificate(
         const vector<uint8_t>& publicKey, const vector<uint8_t>& signingKey,
         const string& serialDecimal, const string& issuer, const string& subject,
-        time_t validityNotBefore, time_t validityNotAfter);
+        time_t validityNotBefore, time_t validityNotAfter,
+        const map<string, vector<uint8_t>>& extensions);
 
 // Performs Elliptic-curve Diffie-Helman using |publicKey| (which must be in the
 // format returned by ecKeyPairGetPublicKey()) and |privateKey| (which must be
diff --git a/identity/support/src/IdentityCredentialSupport.cpp b/identity/support/src/IdentityCredentialSupport.cpp
index 093120d..38348ac 100644
--- a/identity/support/src/IdentityCredentialSupport.cpp
+++ b/identity/support/src/IdentityCredentialSupport.cpp
@@ -344,15 +344,22 @@
 // Crypto functionality / abstraction.
 // ---------------------------------------------------------------------------
 
-struct EVP_CIPHER_CTX_Deleter {
-    void operator()(EVP_CIPHER_CTX* ctx) const {
-        if (ctx != nullptr) {
-            EVP_CIPHER_CTX_free(ctx);
-        }
-    }
-};
-
-using EvpCipherCtxPtr = unique_ptr<EVP_CIPHER_CTX, EVP_CIPHER_CTX_Deleter>;
+using EvpCipherCtxPtr = bssl::UniquePtr<EVP_CIPHER_CTX>;
+using EC_KEY_Ptr = bssl::UniquePtr<EC_KEY>;
+using EVP_PKEY_Ptr = bssl::UniquePtr<EVP_PKEY>;
+using EVP_PKEY_CTX_Ptr = bssl::UniquePtr<EVP_PKEY_CTX>;
+using EC_GROUP_Ptr = bssl::UniquePtr<EC_GROUP>;
+using EC_POINT_Ptr = bssl::UniquePtr<EC_POINT>;
+using ECDSA_SIG_Ptr = bssl::UniquePtr<ECDSA_SIG>;
+using X509_Ptr = bssl::UniquePtr<X509>;
+using PKCS12_Ptr = bssl::UniquePtr<PKCS12>;
+using BIGNUM_Ptr = bssl::UniquePtr<BIGNUM>;
+using ASN1_INTEGER_Ptr = bssl::UniquePtr<ASN1_INTEGER>;
+using ASN1_TIME_Ptr = bssl::UniquePtr<ASN1_TIME>;
+using ASN1_OCTET_STRING_Ptr = bssl::UniquePtr<ASN1_OCTET_STRING>;
+using ASN1_OBJECT_Ptr = bssl::UniquePtr<ASN1_OBJECT>;
+using X509_NAME_Ptr = bssl::UniquePtr<X509_NAME>;
+using X509_EXTENSION_Ptr = bssl::UniquePtr<X509_EXTENSION>;
 
 // bool getRandom(size_t numBytes, vector<uint8_t>& output) {
 optional<vector<uint8_t>> getRandom(size_t numBytes) {
@@ -534,115 +541,6 @@
     return encryptedData;
 }
 
-struct EC_KEY_Deleter {
-    void operator()(EC_KEY* key) const {
-        if (key != nullptr) {
-            EC_KEY_free(key);
-        }
-    }
-};
-using EC_KEY_Ptr = unique_ptr<EC_KEY, EC_KEY_Deleter>;
-
-struct EVP_PKEY_Deleter {
-    void operator()(EVP_PKEY* key) const {
-        if (key != nullptr) {
-            EVP_PKEY_free(key);
-        }
-    }
-};
-using EVP_PKEY_Ptr = unique_ptr<EVP_PKEY, EVP_PKEY_Deleter>;
-
-struct EVP_PKEY_CTX_Deleter {
-    void operator()(EVP_PKEY_CTX* ctx) const {
-        if (ctx != nullptr) {
-            EVP_PKEY_CTX_free(ctx);
-        }
-    }
-};
-using EVP_PKEY_CTX_Ptr = unique_ptr<EVP_PKEY_CTX, EVP_PKEY_CTX_Deleter>;
-
-struct EC_GROUP_Deleter {
-    void operator()(EC_GROUP* group) const {
-        if (group != nullptr) {
-            EC_GROUP_free(group);
-        }
-    }
-};
-using EC_GROUP_Ptr = unique_ptr<EC_GROUP, EC_GROUP_Deleter>;
-
-struct EC_POINT_Deleter {
-    void operator()(EC_POINT* point) const {
-        if (point != nullptr) {
-            EC_POINT_free(point);
-        }
-    }
-};
-
-using EC_POINT_Ptr = unique_ptr<EC_POINT, EC_POINT_Deleter>;
-
-struct ECDSA_SIG_Deleter {
-    void operator()(ECDSA_SIG* sig) const {
-        if (sig != nullptr) {
-            ECDSA_SIG_free(sig);
-        }
-    }
-};
-using ECDSA_SIG_Ptr = unique_ptr<ECDSA_SIG, ECDSA_SIG_Deleter>;
-
-struct X509_Deleter {
-    void operator()(X509* x509) const {
-        if (x509 != nullptr) {
-            X509_free(x509);
-        }
-    }
-};
-using X509_Ptr = unique_ptr<X509, X509_Deleter>;
-
-struct PKCS12_Deleter {
-    void operator()(PKCS12* pkcs12) const {
-        if (pkcs12 != nullptr) {
-            PKCS12_free(pkcs12);
-        }
-    }
-};
-using PKCS12_Ptr = unique_ptr<PKCS12, PKCS12_Deleter>;
-
-struct BIGNUM_Deleter {
-    void operator()(BIGNUM* bignum) const {
-        if (bignum != nullptr) {
-            BN_free(bignum);
-        }
-    }
-};
-using BIGNUM_Ptr = unique_ptr<BIGNUM, BIGNUM_Deleter>;
-
-struct ASN1_INTEGER_Deleter {
-    void operator()(ASN1_INTEGER* value) const {
-        if (value != nullptr) {
-            ASN1_INTEGER_free(value);
-        }
-    }
-};
-using ASN1_INTEGER_Ptr = unique_ptr<ASN1_INTEGER, ASN1_INTEGER_Deleter>;
-
-struct ASN1_TIME_Deleter {
-    void operator()(ASN1_TIME* value) const {
-        if (value != nullptr) {
-            ASN1_TIME_free(value);
-        }
-    }
-};
-using ASN1_TIME_Ptr = unique_ptr<ASN1_TIME, ASN1_TIME_Deleter>;
-
-struct X509_NAME_Deleter {
-    void operator()(X509_NAME* value) const {
-        if (value != nullptr) {
-            X509_NAME_free(value);
-        }
-    }
-};
-using X509_NAME_Ptr = unique_ptr<X509_NAME, X509_NAME_Deleter>;
-
 vector<uint8_t> certificateChainJoin(const vector<vector<uint8_t>>& certificateChain) {
     vector<uint8_t> ret;
     for (const vector<uint8_t>& certificate : certificateChain) {
@@ -1221,8 +1119,19 @@
         return {};
     }
     vector<uint8_t> privateKey;
-    privateKey.resize(BN_num_bytes(bignum));
-    BN_bn2bin(bignum, privateKey.data());
+
+    // Note that this may return fewer than 32 bytes so pad with zeroes since we
+    // want to always return 32 bytes.
+    size_t numBytes = BN_num_bytes(bignum);
+    if (numBytes > 32) {
+        LOG(ERROR) << "Size is " << numBytes << ", expected this to be 32 or less";
+        return {};
+    }
+    privateKey.resize(32);
+    for (size_t n = 0; n < 32 - numBytes; n++) {
+        privateKey[n] = 0x00;
+    }
+    BN_bn2bin(bignum, privateKey.data() + 32 - numBytes);
     return privateKey;
 }
 
@@ -1379,7 +1288,8 @@
 optional<vector<uint8_t>> ecPublicKeyGenerateCertificate(
         const vector<uint8_t>& publicKey, const vector<uint8_t>& signingKey,
         const string& serialDecimal, const string& issuer, const string& subject,
-        time_t validityNotBefore, time_t validityNotAfter) {
+        time_t validityNotBefore, time_t validityNotAfter,
+        const map<string, vector<uint8_t>>& extensions) {
     auto group = EC_GROUP_Ptr(EC_GROUP_new_by_curve_name(NID_X9_62_prime256v1));
     auto point = EC_POINT_Ptr(EC_POINT_new(group.get()));
     if (EC_POINT_oct2point(group.get(), point.get(), publicKey.data(), publicKey.size(), nullptr) !=
@@ -1482,6 +1392,32 @@
         return {};
     }
 
+    for (auto const& [oidStr, blob] : extensions) {
+        ASN1_OBJECT_Ptr oid(
+                OBJ_txt2obj(oidStr.c_str(), 1));  // accept numerical dotted string form only
+        if (!oid.get()) {
+            LOG(ERROR) << "Error setting OID";
+            return {};
+        }
+        ASN1_OCTET_STRING_Ptr octetString(ASN1_OCTET_STRING_new());
+        if (!ASN1_OCTET_STRING_set(octetString.get(), blob.data(), blob.size())) {
+            LOG(ERROR) << "Error setting octet string for extension";
+            return {};
+        }
+
+        X509_EXTENSION_Ptr extension = X509_EXTENSION_Ptr(X509_EXTENSION_new());
+        extension.reset(X509_EXTENSION_create_by_OBJ(nullptr, oid.get(), 0 /* not critical */,
+                                                     octetString.get()));
+        if (!extension.get()) {
+            LOG(ERROR) << "Error setting extension";
+            return {};
+        }
+        if (!X509_add_ext(x509.get(), extension.get(), -1)) {
+            LOG(ERROR) << "Error adding extension";
+            return {};
+        }
+    }
+
     if (X509_sign(x509.get(), privPkey.get(), EVP_sha256()) == 0) {
         LOG(ERROR) << "Error signing X509 certificate";
         return {};
@@ -1650,6 +1586,44 @@
     return publicKey;
 }
 
+optional<vector<uint8_t>> certificateGetExtension(const vector<uint8_t>& x509Certificate,
+                                                  const string& oidStr) {
+    vector<X509_Ptr> certs;
+    if (!parseX509Certificates(x509Certificate, certs)) {
+        return {};
+    }
+    if (certs.size() < 1) {
+        LOG(ERROR) << "No certificates in chain";
+        return {};
+    }
+
+    ASN1_OBJECT_Ptr oid(
+            OBJ_txt2obj(oidStr.c_str(), 1));  // accept numerical dotted string form only
+    if (!oid.get()) {
+        LOG(ERROR) << "Error setting OID";
+        return {};
+    }
+
+    int location = X509_get_ext_by_OBJ(certs[0].get(), oid.get(), -1 /* search from beginning */);
+    if (location == -1) {
+        return {};
+    }
+
+    X509_EXTENSION* ext = X509_get_ext(certs[0].get(), location);
+    if (ext == nullptr) {
+        return {};
+    }
+
+    ASN1_OCTET_STRING* octetString = X509_EXTENSION_get_data(ext);
+    if (octetString == nullptr) {
+        return {};
+    }
+    vector<uint8_t> result;
+    result.resize(octetString->length);
+    memcpy(result.data(), octetString->data, octetString->length);
+    return result;
+}
+
 optional<pair<size_t, size_t>> certificateFindPublicKey(const vector<uint8_t>& x509Certificate) {
     vector<X509_Ptr> certs;
     if (!parseX509Certificates(x509Certificate, certs)) {
diff --git a/identity/support/tests/IdentityCredentialSupportTest.cpp b/identity/support/tests/IdentityCredentialSupportTest.cpp
index 266f263..509133c 100644
--- a/identity/support/tests/IdentityCredentialSupportTest.cpp
+++ b/identity/support/tests/IdentityCredentialSupportTest.cpp
@@ -271,7 +271,7 @@
         optional<vector<uint8_t>> pubKey = support::ecKeyPairGetPublicKey(keyPair.value());
 
         optional<vector<uint8_t>> cert = support::ecPublicKeyGenerateCertificate(
-                pubKey.value(), privKey.value(), "0001", "someIssuer", "someSubject", 0, 0);
+                pubKey.value(), privKey.value(), "0001", "someIssuer", "someSubject", 0, 0, {});
         certs.push_back(cert.value());
     }
     return support::certificateChainJoin(certs);
@@ -338,7 +338,7 @@
     ASSERT_TRUE(pubKey);
 
     optional<vector<uint8_t>> cert = support::ecPublicKeyGenerateCertificate(
-            pubKey.value(), privKey.value(), "0001", "someIssuer", "someSubject", 0, 0);
+            pubKey.value(), privKey.value(), "0001", "someIssuer", "someSubject", 0, 0, {});
 
     optional<vector<uint8_t>> extractedPubKey =
             support::certificateChainGetTopMostKey(cert.value());
@@ -358,7 +358,7 @@
     optional<vector<uint8_t>> otherPubKey = support::ecKeyPairGetPublicKey(keyPair.value());
     ASSERT_TRUE(otherPubKey);
     optional<vector<uint8_t>> otherCert = support::ecPublicKeyGenerateCertificate(
-            otherPubKey.value(), privKey.value(), "0001", "someIssuer", "someSubject", 0, 0);
+            otherPubKey.value(), privKey.value(), "0001", "someIssuer", "someSubject", 0, 0, {});
 
     // Now both cert and otherCert are two distinct certificates. Let's make a
     // chain and check that certificateChainSplit() works as expected.