Keystore 2.0: Add @IntDef for Keystore namespaces.

Bug: 182914789
Test: N/A
Change-Id: Ibdfd2a4a37d7200317ef449ef857f34401625237

4 files changed, 30 insertions, 16 deletions

diff --git a/keystore/java/android/security/keystore/KeyGenParameterSpec.java b/keystore/java/android/security/keystore/KeyGenParameterSpec.java
index 5cb2c3b41517..9ca551b26aab 100644
--- a/keystore/java/android/security/keystore/KeyGenParameterSpec.java
+++ b/keystore/java/android/security/keystore/KeyGenParameterSpec.java
@@ -288,7 +288,7 @@ public final class KeyGenParameterSpec implements AlgorithmParameterSpec, UserAu
     private static final Date DEFAULT_CERT_NOT_AFTER = new Date(2461449600000L); // Jan 1 2048
 
     private final String mKeystoreAlias;
-    private final int mNamespace;
+    private final @KeyProperties.Namespace int mNamespace;
     private final int mKeySize;
     private final AlgorithmParameterSpec mSpec;
     private final X500Principal mCertificateSubject;
@@ -331,7 +331,7 @@ public final class KeyGenParameterSpec implements AlgorithmParameterSpec, UserAu
      */
     public KeyGenParameterSpec(
             String keyStoreAlias,
-            int namespace,
+            @KeyProperties.Namespace int namespace,
             int keySize,
             AlgorithmParameterSpec spec,
             X500Principal certificateSubject,
@@ -472,7 +472,7 @@ public final class KeyGenParameterSpec implements AlgorithmParameterSpec, UserAu
      * @hide
      */
     @SystemApi
-    public int getNamespace() {
+    public @KeyProperties.Namespace int getNamespace() {
         return mNamespace;
     }
 
@@ -896,7 +896,7 @@ public final class KeyGenParameterSpec implements AlgorithmParameterSpec, UserAu
         private final String mKeystoreAlias;
         private @KeyProperties.PurposeEnum int mPurposes;
 
-        private int mNamespace = KeyProperties.NAMESPACE_APPLICATION;
+        private @KeyProperties.Namespace int mNamespace = KeyProperties.NAMESPACE_APPLICATION;
         private int mKeySize = -1;
         private AlgorithmParameterSpec mSpec;
         private X500Principal mCertificateSubject;
@@ -1051,7 +1051,7 @@ public final class KeyGenParameterSpec implements AlgorithmParameterSpec, UserAu
          */
         @SystemApi
         @NonNull
-        public Builder setNamespace(int namespace) {
+        public Builder setNamespace(@KeyProperties.Namespace int namespace) {
             mNamespace = namespace;
             return this;
         }
diff --git a/keystore/java/android/security/keystore/KeyProperties.java b/keystore/java/android/security/keystore/KeyProperties.java
index 7b0fa91380e1..682d12a65ea3 100644
--- a/keystore/java/android/security/keystore/KeyProperties.java
+++ b/keystore/java/android/security/keystore/KeyProperties.java
@@ -892,6 +892,22 @@ public abstract class KeyProperties {
     }
 
     /**
+     * Namespaces provide system developers and vendors with a way to use keystore without
+     * requiring an applications uid. Namespaces can be configured using SEPolicy.
+     * See <a href="https://source.android.com/security/keystore#access-control">
+     *     Keystore 2.0 access-control</a>
+     * {@See KeyGenParameterSpec.Builder#setNamespace}
+     * {@See android.security.keystore2.AndroidKeyStoreLoadStoreParameter}
+     * @hide
+     */
+    @Retention(RetentionPolicy.SOURCE)
+    @IntDef(prefix = { "NAMESPACE_" }, value = {
+            NAMESPACE_APPLICATION,
+            NAMESPACE_WIFI,
+    })
+    public @interface Namespace {}
+
+    /**
      * This value indicates the implicit keystore namespace of the calling application.
      * It is used by default. Only select system components can choose a different namespace
      * which it must be configured in SEPolicy.
@@ -912,14 +928,12 @@ public abstract class KeyProperties {
      * For legacy support, translate namespaces into known UIDs.
      * @hide
      */
-    public static int namespaceToLegacyUid(int namespace) {
+    public static int namespaceToLegacyUid(@Namespace int namespace) {
         switch (namespace) {
             case NAMESPACE_APPLICATION:
                 return KeyStore.UID_SELF;
             case NAMESPACE_WIFI:
                 return Process.WIFI_UID;
-            // TODO Translate WIFI and VPN UIDs once the namespaces are defined.
-            //  b/171305388 and b/171305607
             default:
                 throw new IllegalArgumentException("No UID corresponding to namespace "
                         + namespace);
@@ -930,14 +944,12 @@ public abstract class KeyProperties {
      * For legacy support, translate namespaces into known UIDs.
      * @hide
      */
-    public static int legacyUidToNamespace(int uid) {
+    public static @Namespace int legacyUidToNamespace(int uid) {
         switch (uid) {
             case KeyStore.UID_SELF:
                 return NAMESPACE_APPLICATION;
             case Process.WIFI_UID:
                 return NAMESPACE_WIFI;
-            // TODO Translate WIFI and VPN UIDs once the namespaces are defined.
-            //  b/171305388 and b/171305607
             default:
                 throw new IllegalArgumentException("No namespace corresponding to uid "
                         + uid);
diff --git a/keystore/java/android/security/keystore2/AndroidKeyStoreLoadStoreParameter.java b/keystore/java/android/security/keystore2/AndroidKeyStoreLoadStoreParameter.java
index 0c6744f9822c..25b1c864b5d1 100644
--- a/keystore/java/android/security/keystore2/AndroidKeyStoreLoadStoreParameter.java
+++ b/keystore/java/android/security/keystore2/AndroidKeyStoreLoadStoreParameter.java
@@ -16,6 +16,8 @@
 
 package android.security.keystore2;
 
+import android.security.keystore.KeyProperties;
+
 import java.security.KeyStore;
 import java.security.KeyStore.ProtectionParameter;
 
@@ -24,9 +26,9 @@ import java.security.KeyStore.ProtectionParameter;
  */
 public class AndroidKeyStoreLoadStoreParameter implements KeyStore.LoadStoreParameter {
 
-    private final int mNamespace;
+    private final @KeyProperties.Namespace int mNamespace;
 
-    public AndroidKeyStoreLoadStoreParameter(int namespace) {
+    public AndroidKeyStoreLoadStoreParameter(@KeyProperties.Namespace int namespace) {
         mNamespace = namespace;
     }
 
@@ -35,7 +37,7 @@ public class AndroidKeyStoreLoadStoreParameter implements KeyStore.LoadStorePara
         return null;
     }
 
-    int getNamespace() {
+    @KeyProperties.Namespace int getNamespace() {
         return mNamespace;
     }
 }
diff --git a/keystore/java/android/security/keystore2/AndroidKeyStoreSpi.java b/keystore/java/android/security/keystore2/AndroidKeyStoreSpi.java
index 39607aeb3852..32f98a2538f3 100644
--- a/keystore/java/android/security/keystore2/AndroidKeyStoreSpi.java
+++ b/keystore/java/android/security/keystore2/AndroidKeyStoreSpi.java
@@ -100,7 +100,7 @@ public class AndroidKeyStoreSpi extends KeyStoreSpi {
     public static final String NAME = "AndroidKeyStore";
 
     private KeyStore2 mKeyStore;
-    private int mNamespace = KeyProperties.NAMESPACE_APPLICATION;
+    private @KeyProperties.Namespace int mNamespace = KeyProperties.NAMESPACE_APPLICATION;
 
     @Override
     public Key engineGetKey(String alias, char[] password) throws NoSuchAlgorithmException,
@@ -1125,7 +1125,7 @@ public class AndroidKeyStoreSpi extends KeyStoreSpi {
     @Override
     public void engineLoad(LoadStoreParameter param) throws IOException,
             NoSuchAlgorithmException, CertificateException {
-        int namespace = KeyProperties.NAMESPACE_APPLICATION;
+        @KeyProperties.Namespace int namespace = KeyProperties.NAMESPACE_APPLICATION;
         if (param != null) {
             if (param instanceof AndroidKeyStoreLoadStoreParameter) {
                 namespace = ((AndroidKeyStoreLoadStoreParameter) param).getNamespace();