Merge "Revise secure key import API after review" into pi-dev

am: 50228a6471

Change-Id: I4fe07806b781d337f2df40f34fb75662187f4360

9 files changed, 157 insertions, 12 deletions

diff --git a/api/current.txt b/api/current.txt
index bea1b2a1dc34..47ce87d0d03b 100644
--- a/api/current.txt
+++ b/api/current.txt
@@ -38729,7 +38729,18 @@ package android.security.keystore {
     method public android.security.keystore.KeyProtection.Builder setUserConfirmationRequired(boolean);
   }
 
+  public class SecureKeyImportUnavailableException extends java.security.ProviderException {
+    ctor public SecureKeyImportUnavailableException();
+    ctor public SecureKeyImportUnavailableException(java.lang.String);
+    ctor public SecureKeyImportUnavailableException(java.lang.String, java.lang.Throwable);
+    ctor public SecureKeyImportUnavailableException(java.lang.Throwable);
+  }
+
   public class StrongBoxUnavailableException extends java.security.ProviderException {
+    ctor public StrongBoxUnavailableException();
+    ctor public StrongBoxUnavailableException(java.lang.String);
+    ctor public StrongBoxUnavailableException(java.lang.String, java.lang.Throwable);
+    ctor public StrongBoxUnavailableException(java.lang.Throwable);
   }
 
   public class UserNotAuthenticatedException extends java.security.InvalidKeyException {
diff --git a/keystore/java/android/security/keystore/AndroidKeyStoreBCWorkaroundProvider.java b/keystore/java/android/security/keystore/AndroidKeyStoreBCWorkaroundProvider.java
index e4cf84afcb8f..cc805605bdf8 100644
--- a/keystore/java/android/security/keystore/AndroidKeyStoreBCWorkaroundProvider.java
+++ b/keystore/java/android/security/keystore/AndroidKeyStoreBCWorkaroundProvider.java
@@ -93,15 +93,17 @@ class AndroidKeyStoreBCWorkaroundProvider extends Provider {
         putSymmetricCipherImpl("AES/CTR/NoPadding",
                 PACKAGE_NAME + ".AndroidKeyStoreUnauthenticatedAESCipherSpi$CTR$NoPadding");
 
-        putSymmetricCipherImpl("DESede/CBC/NoPadding",
+        if ("true".equals(System.getProperty("supports3DES"))) {
+            putSymmetricCipherImpl("DESede/CBC/NoPadding",
                 PACKAGE_NAME + ".AndroidKeyStore3DESCipherSpi$CBC$NoPadding");
-        putSymmetricCipherImpl("DESede/CBC/PKCS7Padding",
+            putSymmetricCipherImpl("DESede/CBC/PKCS7Padding",
                 PACKAGE_NAME + ".AndroidKeyStore3DESCipherSpi$CBC$PKCS7Padding");
 
-        putSymmetricCipherImpl("DESede/ECB/NoPadding",
+            putSymmetricCipherImpl("DESede/ECB/NoPadding",
                 PACKAGE_NAME + ".AndroidKeyStore3DESCipherSpi$ECB$NoPadding");
-        putSymmetricCipherImpl("DESede/ECB/PKCS7Padding",
+            putSymmetricCipherImpl("DESede/ECB/PKCS7Padding",
                 PACKAGE_NAME + ".AndroidKeyStore3DESCipherSpi$ECB$PKCS7Padding");
+        }
 
         putSymmetricCipherImpl("AES/GCM/NoPadding",
                 PACKAGE_NAME + ".AndroidKeyStoreAuthenticatedAESCipherSpi$GCM$NoPadding");
diff --git a/keystore/java/android/security/keystore/AndroidKeyStoreKeyPairGeneratorSpi.java b/keystore/java/android/security/keystore/AndroidKeyStoreKeyPairGeneratorSpi.java
index d68a33de2c61..5fc742afeaeb 100644
--- a/keystore/java/android/security/keystore/AndroidKeyStoreKeyPairGeneratorSpi.java
+++ b/keystore/java/android/security/keystore/AndroidKeyStoreKeyPairGeneratorSpi.java
@@ -475,6 +475,12 @@ public abstract class AndroidKeyStoreKeyPairGeneratorSpi extends KeyPairGenerato
 
             success = true;
             return keyPair;
+        } catch (ProviderException e) {
+          if ((mSpec.getPurposes() & KeyProperties.PURPOSE_WRAP_KEY) != 0) {
+              throw new SecureKeyImportUnavailableException(e);
+          } else {
+              throw e;
+          }
         } finally {
             if (!success) {
                 Credentials.deleteAllTypesForAlias(mKeyStore, mEntryAlias, mEntryUid);
diff --git a/keystore/java/android/security/keystore/AndroidKeyStoreProvider.java b/keystore/java/android/security/keystore/AndroidKeyStoreProvider.java
index 2c45d43da3f1..9b7695daf5ff 100644
--- a/keystore/java/android/security/keystore/AndroidKeyStoreProvider.java
+++ b/keystore/java/android/security/keystore/AndroidKeyStoreProvider.java
@@ -67,6 +67,8 @@ public class AndroidKeyStoreProvider extends Provider {
     public AndroidKeyStoreProvider() {
         super(PROVIDER_NAME, 1.0, "Android KeyStore security provider");
 
+        boolean supports3DES = "true".equals(System.getProperty("supports3DES"));
+
         // java.security.KeyStore
         put("KeyStore.AndroidKeyStore", PACKAGE_NAME + ".AndroidKeyStoreSpi");
 
@@ -80,16 +82,21 @@ public class AndroidKeyStoreProvider extends Provider {
 
         // javax.crypto.KeyGenerator
         put("KeyGenerator.AES", PACKAGE_NAME + ".AndroidKeyStoreKeyGeneratorSpi$AES");
-        put("KeyGenerator.DESede", PACKAGE_NAME + ".AndroidKeyStoreKeyGeneratorSpi$DESede");
         put("KeyGenerator.HmacSHA1", PACKAGE_NAME + ".AndroidKeyStoreKeyGeneratorSpi$HmacSHA1");
         put("KeyGenerator.HmacSHA224", PACKAGE_NAME + ".AndroidKeyStoreKeyGeneratorSpi$HmacSHA224");
         put("KeyGenerator.HmacSHA256", PACKAGE_NAME + ".AndroidKeyStoreKeyGeneratorSpi$HmacSHA256");
         put("KeyGenerator.HmacSHA384", PACKAGE_NAME + ".AndroidKeyStoreKeyGeneratorSpi$HmacSHA384");
         put("KeyGenerator.HmacSHA512", PACKAGE_NAME + ".AndroidKeyStoreKeyGeneratorSpi$HmacSHA512");
 
+        if (supports3DES) {
+            put("KeyGenerator.DESede", PACKAGE_NAME + ".AndroidKeyStoreKeyGeneratorSpi$DESede");
+        }
+
         // java.security.SecretKeyFactory
         putSecretKeyFactoryImpl("AES");
-        putSecretKeyFactoryImpl("DESede");
+        if (supports3DES) {
+            putSecretKeyFactoryImpl("DESede");
+        }
         putSecretKeyFactoryImpl("HmacSHA1");
         putSecretKeyFactoryImpl("HmacSHA224");
         putSecretKeyFactoryImpl("HmacSHA256");
diff --git a/keystore/java/android/security/keystore/AndroidKeyStoreSpi.java b/keystore/java/android/security/keystore/AndroidKeyStoreSpi.java
index fc86ca0443b0..3e9853c455e5 100644
--- a/keystore/java/android/security/keystore/AndroidKeyStoreSpi.java
+++ b/keystore/java/android/security/keystore/AndroidKeyStoreSpi.java
@@ -26,6 +26,7 @@ import android.security.keymaster.KeymasterArguments;
 import android.security.keymaster.KeymasterDefs;
 import android.security.keystore.KeyProperties;
 import android.security.keystore.KeyProtection;
+import android.security.keystore.SecureKeyImportUnavailableException;
 import android.security.keystore.WrappedKeyEntry;
 import android.util.Log;
 
@@ -755,7 +756,9 @@ public class AndroidKeyStoreSpi extends KeyStoreSpi {
             0, // FIXME fingerprint id?
             mUid,
             new KeyCharacteristics());
-        if (errorCode != KeyStore.NO_ERROR) {
+        if (errorCode == KeymasterDefs.KM_ERROR_UNIMPLEMENTED) {
+          throw new SecureKeyImportUnavailableException("Could not import wrapped key");
+        } else if (errorCode != KeyStore.NO_ERROR) {
             throw new KeyStoreException("Failed to import wrapped key. Keystore error code: "
                 + errorCode);
         }
diff --git a/keystore/java/android/security/keystore/KeyProperties.java b/keystore/java/android/security/keystore/KeyProperties.java
index f54b6decc5c4..f12a659039ee 100644
--- a/keystore/java/android/security/keystore/KeyProperties.java
+++ b/keystore/java/android/security/keystore/KeyProperties.java
@@ -689,7 +689,11 @@ public abstract class KeyProperties {
      */
     public static final int ORIGIN_UNKNOWN = 1 << 2;
 
-    /** Key was imported into the AndroidKeyStore in an encrypted wrapper */
+    /**
+     * Key was imported into the AndroidKeyStore in an encrypted wrapper. Unlike imported keys,
+     * securely imported keys can be imported without appearing as plaintext in the device's host
+     * memory.
+     */
     public static final int ORIGIN_SECURELY_IMPORTED = 1 << 3;
 
 
diff --git a/keystore/java/android/security/keystore/SecureKeyImportUnavailableException.java b/keystore/java/android/security/keystore/SecureKeyImportUnavailableException.java
new file mode 100644
index 000000000000..d1cc572bdaf7
--- /dev/null
+++ b/keystore/java/android/security/keystore/SecureKeyImportUnavailableException.java
@@ -0,0 +1,46 @@
+/*
+ * 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.security.KeyStore;
+import android.security.KeyStoreException;
+
+import java.security.ProviderException;
+
+/**
+ * Indicates that the Keystore does not support securely importing wrapped keys.
+ */
+public class SecureKeyImportUnavailableException extends ProviderException {
+
+    public SecureKeyImportUnavailableException() {
+        super();
+    }
+
+    public SecureKeyImportUnavailableException(String message) {
+        super(message, new KeyStoreException(KeyStore.HARDWARE_TYPE_UNAVAILABLE,
+                "Secure Key Import not available"));
+    }
+
+    public SecureKeyImportUnavailableException(String message, Throwable cause) {
+        super(message, cause);
+    }
+
+    public SecureKeyImportUnavailableException(Throwable cause) {
+        super(cause);
+    }
+}
+
diff --git a/keystore/java/android/security/keystore/StrongBoxUnavailableException.java b/keystore/java/android/security/keystore/StrongBoxUnavailableException.java
index 66a77ed1a0de..6c7e9a9521e0 100644
--- a/keystore/java/android/security/keystore/StrongBoxUnavailableException.java
+++ b/keystore/java/android/security/keystore/StrongBoxUnavailableException.java
@@ -27,13 +27,22 @@ import java.security.ProviderException;
  */
 public class StrongBoxUnavailableException extends ProviderException {
 
-    /**
-     * @hide
-     */
+    public StrongBoxUnavailableException() {
+        super();
+    }
+
     public StrongBoxUnavailableException(String message) {
         super(message,
                 new KeyStoreException(KeyStore.HARDWARE_TYPE_UNAVAILABLE, "No StrongBox available")
         );
     }
+
+    public StrongBoxUnavailableException(String message, Throwable cause) {
+        super(message, cause);
+    }
+
+    public StrongBoxUnavailableException(Throwable cause) {
+        super(cause);
+    }
 }
 
diff --git a/keystore/java/android/security/keystore/WrappedKeyEntry.java b/keystore/java/android/security/keystore/WrappedKeyEntry.java
index a8f4afe7a201..7155686b1385 100644
--- a/keystore/java/android/security/keystore/WrappedKeyEntry.java
+++ b/keystore/java/android/security/keystore/WrappedKeyEntry.java
@@ -21,7 +21,55 @@ import java.security.KeyStore.Entry;
 import java.security.spec.AlgorithmParameterSpec;
 
 /**
- * An {@link Entry} that holds a wrapped key.
+ * An {@link Entry} that holds a wrapped key. Wrapped keys contain encrypted key data and
+ * description information that can be used to securely import key material into a hardware-backed
+ * Keystore.
+ *
+ * <p>
+ *   The wrapped key is in DER-encoded ASN.1 format, specified by the following schema:
+ * </p>
+ *
+ * <pre>
+ *     KeyDescription ::= SEQUENCE(
+ *         keyFormat INTEGER,                   # Values from KeyFormat enum.
+ *         keyParams AuthorizationList,
+ *     )
+ *
+ *     SecureKeyWrapper ::= SEQUENCE(
+ *         version INTEGER,                     # Contains value 0
+ *         encryptedTransportKey OCTET_STRING,
+ *         initializationVector OCTET_STRING,
+ *         keyDescription KeyDescription,
+ *         encryptedKey OCTET_STRING,
+ *         tag OCTET_STRING
+ *     )
+ * </pre>
+ * <ul>
+ *     <li>keyFormat is an integer from the KeyFormat enum, defining the format of the plaintext
+ *       key material.
+ *     </li>
+ *     <li>keyParams is the characteristics of the key to be imported (as with generateKey or
+ *       importKey).  If the secure import is successful, these characteristics must be
+ *       associated with the key exactly as if the key material had been insecurely imported
+ *       with importKey. See <a href="https://developer.android.com/training/articles/security-key-attestation.html#certificate_schema">Key Attestation</a> for the AuthorizationList format.
+ *     </li>
+ *     <li>encryptedTransportKey is a 256-bit AES key, XORed with a masking key and then encrypted
+ *       in RSA-OAEP mode (SHA-256 digest, SHA-1 MGF1 digest) with the wrapping key specified by
+ *       wrappingKeyBlob.
+ *     </li>
+ *     <li>keyDescription is a KeyDescription, above.
+ *     </li>
+ *     <li>encryptedKey is the key material of the key to be imported, in format keyFormat, and
+ *       encrypted with encryptedEphemeralKey in AES-GCM mode, with the DER-encoded
+ *       representation of keyDescription provided as additional authenticated data.
+ *     </li>
+ *     <li>tag is the tag produced by the AES-GCM encryption of encryptedKey.
+ *     </li>
+ *</ul>
+ *
+ * <p>
+ *     Imported wrapped keys will have KeymasterDefs.KM_ORIGIN_SECURELY_IMPORTED
+ * </p>
  */
 public class WrappedKeyEntry implements Entry {
 
@@ -30,6 +78,14 @@ public class WrappedKeyEntry implements Entry {
     private final String mTransformation;
     private final AlgorithmParameterSpec mAlgorithmParameterSpec;
 
+    /**
+     * Constructs a {@link WrappedKeyEntry} with a binary wrapped key.
+     *
+     * @param wrappedKeyBytes ASN.1 DER encoded wrapped key
+     * @param wrappingKeyAlias identifies the private key that can unwrap the wrapped key
+     * @param transformation used to unwrap the key. ex: "RSA/ECB/OAEPPadding"
+     * @param algorithmParameterSpec spec for the private key used to unwrap the wrapped key
+     */
     public WrappedKeyEntry(byte[] wrappedKeyBytes, String wrappingKeyAlias, String transformation,
             AlgorithmParameterSpec algorithmParameterSpec) {
         mWrappedKeyBytes = wrappedKeyBytes;
@@ -54,3 +110,4 @@ public class WrappedKeyEntry implements Entry {
         return mAlgorithmParameterSpec;
     }
 }
+