Merge "ECDH SPI interface" (e43b86d5) · Commits · e / os / android_frameworks_base

core/api/current.txt

+1 −0

Original line number	Diff line number	Diff line
		@@ -36325,6 +36325,7 @@ package android.security.keystore {
		field public static final int ORIGIN_IMPORTED = 2; // 0x2
		field public static final int ORIGIN_SECURELY_IMPORTED = 8; // 0x8
		field public static final int ORIGIN_UNKNOWN = 4; // 0x4
		field public static final int PURPOSE_AGREE_KEY = 64; // 0x40
		field public static final int PURPOSE_DECRYPT = 2; // 0x2
		field public static final int PURPOSE_ENCRYPT = 1; // 0x1
		field public static final int PURPOSE_SIGN = 4; // 0x4

core/java/android/security/keymaster/KeymasterDefs.java

+1 −0

Original line number	Diff line number	Diff line
		@@ -177,6 +177,7 @@ public final class KeymasterDefs {
		public static final int KM_PURPOSE_SIGN = KeyPurpose.SIGN;
		public static final int KM_PURPOSE_VERIFY = KeyPurpose.VERIFY;
		public static final int KM_PURPOSE_WRAP = KeyPurpose.WRAP_KEY;
		public static final int KM_PURPOSE_AGREE_KEY = KeyPurpose.AGREE_KEY;

		// Key formats.
		public static final int KM_KEY_FORMAT_X509 = KeyFormat.X509;

keystore/java/android/security/keystore/KeyProperties.java

+10 −0

Original line number	Diff line number	Diff line
		@@ -67,6 +67,7 @@ public abstract class KeyProperties {
		PURPOSE_SIGN,
		PURPOSE_VERIFY,
		PURPOSE_WRAP_KEY,
		PURPOSE_AGREE_KEY,
		})
		public @interface PurposeEnum {}

		@@ -95,6 +96,11 @@ public abstract class KeyProperties {
		*/
		public static final int PURPOSE_WRAP_KEY = 1 << 5;

		/**
		* Purpose of key: creating a shared ECDH secret through key agreement.
		*/
		public static final int PURPOSE_AGREE_KEY = 1 << 6;

		/**
		* @hide
		*/
		@@ -113,6 +119,8 @@ public abstract class KeyProperties {
		return KeymasterDefs.KM_PURPOSE_VERIFY;
		case PURPOSE_WRAP_KEY:
		return KeymasterDefs.KM_PURPOSE_WRAP;
		case PURPOSE_AGREE_KEY:
		return KeymasterDefs.KM_PURPOSE_AGREE_KEY;
		default:
		throw new IllegalArgumentException("Unknown purpose: " + purpose);
		}
		@@ -130,6 +138,8 @@ public abstract class KeyProperties {
		return PURPOSE_VERIFY;
		case KeymasterDefs.KM_PURPOSE_WRAP:
		return PURPOSE_WRAP_KEY;
		case KeymasterDefs.KM_PURPOSE_AGREE_KEY:
		return PURPOSE_AGREE_KEY;
		default:
		throw new IllegalArgumentException("Unknown purpose: " + purpose);
		}

keystore/java/android/security/keystore2/AndroidKeyStoreKeyAgreementSpi.java

0 → 100644

+240 −0

Original line number	Diff line number	Diff line
		/*
		* Copyright (C) 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.
		*/

		package android.security.keystore2;

		import android.hardware.security.keymint.Algorithm;
		import android.hardware.security.keymint.KeyParameter;
		import android.hardware.security.keymint.KeyPurpose;
		import android.hardware.security.keymint.Tag;
		import android.security.KeyStoreException;
		import android.security.KeyStoreOperation;
		import android.security.keystore.KeyStoreCryptoOperation;

		import java.security.InvalidAlgorithmParameterException;
		import java.security.InvalidKeyException;
		import java.security.Key;
		import java.security.NoSuchAlgorithmException;
		import java.security.ProviderException;
		import java.security.PublicKey;
		import java.security.SecureRandom;
		import java.security.spec.AlgorithmParameterSpec;
		import java.util.ArrayList;
		import java.util.List;

		import javax.crypto.KeyAgreementSpi;
		import javax.crypto.SecretKey;
		import javax.crypto.ShortBufferException;
		import javax.crypto.spec.SecretKeySpec;

		/**
		* {@link KeyAgreementSpi} which provides an ECDH implementation backed by Android KeyStore.
		*
		* @hide
		*/
		public class AndroidKeyStoreKeyAgreementSpi extends KeyAgreementSpi
		implements KeyStoreCryptoOperation {

		private static final String TAG = "AndroidKeyStoreKeyAgreementSpi";

		/**
		* ECDH implementation.
		*
		* @hide
		*/
		public static class ECDH extends AndroidKeyStoreKeyAgreementSpi {
		public ECDH() {
		super(Algorithm.EC);
		}
		}

		private final int mKeymintAlgorithm;

		// Fields below are populated by engineInit and should be preserved after engineDoFinal.
		private AndroidKeyStorePrivateKey mKey;
		private PublicKey mOtherPartyKey;

		// Fields below are reset when engineDoFinal succeeds.
		private KeyStoreOperation mOperation;
		private long mOperationHandle;

		protected AndroidKeyStoreKeyAgreementSpi(int keymintAlgorithm) {
		resetAll();

		mKeymintAlgorithm = keymintAlgorithm;
		}

		@Override
		protected void engineInit(Key key, SecureRandom random) throws InvalidKeyException {
		resetAll();

		if (key == null) {
		throw new InvalidKeyException("key == null");
		} else if (!(key instanceof AndroidKeyStorePrivateKey)) {
		throw new InvalidKeyException(
		"Only Android KeyStore private keys supported. Key: " + key);
		}
		// Checking the correct KEY_PURPOSE and algorithm is done by the Keymint implementation in
		// ensureKeystoreOperationInitialized() below.
		mKey = (AndroidKeyStorePrivateKey) key;

		boolean success = false;
		try {
		ensureKeystoreOperationInitialized();
		success = true;
		} finally {
		if (!success) {
		resetAll();
		}
		}
		}

		@Override
		protected void engineInit(Key key, AlgorithmParameterSpec params, SecureRandom random)
		throws InvalidKeyException, InvalidAlgorithmParameterException {
		if (params != null) {
		throw new InvalidAlgorithmParameterException(
		"Unsupported algorithm parameters: " + params);
		}
		engineInit(key, random);
		}

		@Override
		protected Key engineDoPhase(Key key, boolean lastPhase)
		throws InvalidKeyException, IllegalStateException {
		ensureKeystoreOperationInitialized();

		if (key == null) {
		throw new InvalidKeyException("key == null");
		} else if (!(key instanceof PublicKey)) {
		throw new InvalidKeyException("Only public keys supported. Key: " + key);
		} else if (!lastPhase) {
		throw new IllegalStateException(
		"Only one other party supported. lastPhase must be set to true.");
		} else if (mOtherPartyKey != null) {
		throw new IllegalStateException(
		"Only one other party supported. doPhase() must only be called exactly once.");
		}
		// The other party key will be passed as part of the doFinal() call, to prevent an
		// additional IPC.
		mOtherPartyKey = (PublicKey) key;

		return null; // No intermediate key
		}

		@Override
		protected byte[] engineGenerateSecret() throws IllegalStateException {
		try {
		ensureKeystoreOperationInitialized();
		} catch (InvalidKeyException e) {
		throw new IllegalStateException("Not initialized", e);
		}

		if (mOtherPartyKey == null) {
		throw new IllegalStateException("Other party key not provided. Call doPhase() first.");
		}
		byte[] otherPartyKeyEncoded = mOtherPartyKey.getEncoded();

		try {
		return mOperation.finish(otherPartyKeyEncoded, null);
		} catch (KeyStoreException e) {
		throw new ProviderException("Keystore operation failed", e);
		} finally {
		resetWhilePreservingInitState();
		}
		}

		@Override
		protected SecretKey engineGenerateSecret(String algorithm)
		throws IllegalStateException, NoSuchAlgorithmException, InvalidKeyException {
		byte[] generatedSecret = engineGenerateSecret();

		return new SecretKeySpec(generatedSecret, algorithm);
		}

		@Override
		protected int engineGenerateSecret(byte[] sharedSecret, int offset)
		throws IllegalStateException, ShortBufferException {
		byte[] generatedSecret = engineGenerateSecret();

		if (generatedSecret.length > sharedSecret.length - offset) {
		throw new ShortBufferException("Needed: " + generatedSecret.length);
		}
		System.arraycopy(generatedSecret, 0, sharedSecret, offset, generatedSecret.length);
		return generatedSecret.length;
		}

		@Override
		public long getOperationHandle() {
		return mOperationHandle;
		}

		@Override
		protected void finalize() throws Throwable {
		try {
		resetAll();
		} finally {
		super.finalize();
		}
		}

		private void resetWhilePreservingInitState() {
		KeyStoreCryptoOperationUtils.abortOperation(mOperation);
		mOperationHandle = 0;
		mOperation = null;
		mOtherPartyKey = null;
		}

		private void resetAll() {
		resetWhilePreservingInitState();
		mKey = null;
		}

		private void ensureKeystoreOperationInitialized()
		throws InvalidKeyException, IllegalStateException {
		if (mKey == null) {
		throw new IllegalStateException("Not initialized");
		}
		if (mOperation != null) {
		return;
		}

		// We don't need to explicitly pass in any other parameters here, as they're part of the
		// private key that is available to Keymint.
		List<KeyParameter> parameters = new ArrayList<>();
		parameters.add(KeyStore2ParameterUtils.makeEnum(
		Tag.PURPOSE, KeyPurpose.AGREE_KEY
		));

		try {
		mOperation =
		mKey.getSecurityLevel().createOperation(mKey.getKeyIdDescriptor(), parameters);
		} catch (KeyStoreException keyStoreException) {
		// If necessary, throw an exception due to KeyStore operation having failed.
		InvalidKeyException e =
		KeyStoreCryptoOperationUtils.getInvalidKeyException(mKey, keyStoreException);
		if (e != null) {
		throw e;
		}
		}

		// Set the operation handle. This will be a random number, or the operation challenge if
		// user authentication is required. If we got a challenge we check if the authorization can
		// possibly succeed.
		mOperationHandle =
		KeyStoreCryptoOperationUtils.getOrMakeOperationChallenge(mOperation, mKey);
		}
		}

keystore/java/android/security/keystore2/AndroidKeyStoreProvider.java

+3 −0

Original line number	Diff line number	Diff line
		@@ -94,6 +94,9 @@ public class AndroidKeyStoreProvider extends Provider {
		put("KeyGenerator.DESede", PACKAGE_NAME + ".AndroidKeyStoreKeyGeneratorSpi$DESede");
		}

		// javax.crypto.KeyAgreement
		put("KeyAgreement.ECDH", PACKAGE_NAME + ".AndroidKeyStoreKeyAgreementSpi$ECDH");

		// java.security.SecretKeyFactory
		putSecretKeyFactoryImpl("AES");
		if (supports3DES) {