| /* |
| * Copyright (C) 2017 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. |
| */ |
| |
| package android.security.keystore; |
| |
| import android.annotation.NonNull; |
| import android.os.Parcel; |
| import android.os.Parcelable; |
| |
| import com.android.internal.util.Preconditions; |
| |
| import java.util.List; |
| |
| /** |
| * A snapshot of a version of the keystore. Two events can trigger the generation of a new snapshot: |
| * |
| * <ul> |
| * <li>The user's lock screen changes. (A key derived from the user's lock screen is used to |
| * protected the keychain, which is why this forces a new snapshot.) |
| * <li>A key is added to or removed from the recoverable keychain. |
| * </ul> |
| * |
| * <p>The snapshot data is also encrypted with the remote trusted hardware's public key, so even |
| * the recovery agent itself should not be able to decipher the data. The recovery agent sends an |
| * instance of this to the remote trusted hardware whenever a new snapshot is generated. During a |
| * recovery flow, the recovery agent retrieves a snapshot from the remote trusted hardware. It then |
| * sends it to the framework, where it is decrypted using the user's lock screen from their previous |
| * device. |
| * |
| * @hide |
| */ |
| public final class KeychainSnapshot implements Parcelable { |
| private int mSnapshotVersion; |
| private List<KeychainProtectionParams> mKeychainProtectionParams; |
| private List<WrappedApplicationKey> mEntryRecoveryData; |
| private byte[] mEncryptedRecoveryKeyBlob; |
| |
| /** |
| * @hide |
| * Deprecated, consider using builder. |
| */ |
| public KeychainSnapshot( |
| int snapshotVersion, |
| @NonNull List<KeychainProtectionParams> keychainProtectionParams, |
| @NonNull List<WrappedApplicationKey> wrappedApplicationKeys, |
| @NonNull byte[] encryptedRecoveryKeyBlob) { |
| mSnapshotVersion = snapshotVersion; |
| mKeychainProtectionParams = |
| Preconditions.checkCollectionElementsNotNull(keychainProtectionParams, |
| "keychainProtectionParams"); |
| mEntryRecoveryData = Preconditions.checkCollectionElementsNotNull(wrappedApplicationKeys, |
| "wrappedApplicationKeys"); |
| mEncryptedRecoveryKeyBlob = Preconditions.checkNotNull(encryptedRecoveryKeyBlob); |
| } |
| |
| private KeychainSnapshot() { |
| |
| } |
| |
| /** |
| * Snapshot version for given account. It is incremented when user secret or list of application |
| * keys changes. |
| */ |
| public int getSnapshotVersion() { |
| return mSnapshotVersion; |
| } |
| |
| /** |
| * UI and key derivation parameters. Note that combination of secrets may be used. |
| */ |
| public @NonNull List<KeychainProtectionParams> getKeychainProtectionParams() { |
| return mKeychainProtectionParams; |
| } |
| |
| /** |
| * List of application keys, with key material encrypted by |
| * the recovery key ({@link #getEncryptedRecoveryKeyBlob}). |
| */ |
| public @NonNull List<WrappedApplicationKey> getWrappedApplicationKeys() { |
| return mEntryRecoveryData; |
| } |
| |
| /** |
| * Recovery key blob, encrypted by user secret and recovery service public key. |
| */ |
| public @NonNull byte[] getEncryptedRecoveryKeyBlob() { |
| return mEncryptedRecoveryKeyBlob; |
| } |
| |
| public static final Parcelable.Creator<KeychainSnapshot> CREATOR = |
| new Parcelable.Creator<KeychainSnapshot>() { |
| public KeychainSnapshot createFromParcel(Parcel in) { |
| return new KeychainSnapshot(in); |
| } |
| |
| public KeychainSnapshot[] newArray(int length) { |
| return new KeychainSnapshot[length]; |
| } |
| }; |
| |
| /** |
| * Builder for creating {@link KeychainSnapshot}. |
| */ |
| public static class Builder { |
| private KeychainSnapshot mInstance = new KeychainSnapshot(); |
| |
| /** |
| * Snapshot version for given account. |
| * |
| * @param snapshotVersion The snapshot version |
| * @return This builder. |
| */ |
| public Builder setSnapshotVersion(int snapshotVersion) { |
| mInstance.mSnapshotVersion = snapshotVersion; |
| return this; |
| } |
| |
| /** |
| * Sets UI and key derivation parameters |
| * |
| * @param recoveryMetadata The UI and key derivation parameters |
| * @return This builder. |
| */ |
| public Builder setKeychainProtectionParams( |
| @NonNull List<KeychainProtectionParams> recoveryMetadata) { |
| mInstance.mKeychainProtectionParams = recoveryMetadata; |
| return this; |
| } |
| |
| /** |
| * List of application keys. |
| * |
| * @param entryRecoveryData List of application keys |
| * @return This builder. |
| */ |
| public Builder setWrappedApplicationKeys(List<WrappedApplicationKey> entryRecoveryData) { |
| mInstance.mEntryRecoveryData = entryRecoveryData; |
| return this; |
| } |
| |
| /** |
| * Sets recovery key blob |
| * |
| * @param encryptedRecoveryKeyBlob The recovery key blob. |
| * @return This builder. |
| */ |
| public Builder setEncryptedRecoveryKeyBlob(@NonNull byte[] encryptedRecoveryKeyBlob) { |
| mInstance.mEncryptedRecoveryKeyBlob = encryptedRecoveryKeyBlob; |
| return this; |
| } |
| |
| |
| /** |
| * Creates a new {@link KeychainSnapshot} instance. |
| * |
| * @return new instance |
| * @throws NullPointerException if some required fields were not set. |
| */ |
| @NonNull public KeychainSnapshot build() { |
| Preconditions.checkCollectionElementsNotNull(mInstance.mKeychainProtectionParams, |
| "recoveryMetadata"); |
| Preconditions.checkCollectionElementsNotNull(mInstance.mEntryRecoveryData, |
| "entryRecoveryData"); |
| Preconditions.checkNotNull(mInstance.mEncryptedRecoveryKeyBlob); |
| return mInstance; |
| } |
| } |
| |
| /** |
| * @hide |
| */ |
| @Override |
| public void writeToParcel(Parcel out, int flags) { |
| out.writeInt(mSnapshotVersion); |
| out.writeTypedList(mKeychainProtectionParams); |
| out.writeByteArray(mEncryptedRecoveryKeyBlob); |
| out.writeTypedList(mEntryRecoveryData); |
| } |
| |
| /** |
| * @hide |
| */ |
| protected KeychainSnapshot(Parcel in) { |
| mSnapshotVersion = in.readInt(); |
| mKeychainProtectionParams = in.createTypedArrayList(KeychainProtectionParams.CREATOR); |
| mEncryptedRecoveryKeyBlob = in.createByteArray(); |
| mEntryRecoveryData = in.createTypedArrayList(WrappedApplicationKey.CREATOR); |
| } |
| |
| @Override |
| public int describeContents() { |
| return 0; |
| } |
| } |