DPM: installKeyPair variant: caller can self-grant

If 'requestAccess' is true, the caller (either profile/device owner or a
designated certificate installer) will be granted usage of the keypair
on successful installation.

This has no security implications for a profile/device owner which would
already be able to self-grant. Delegated certificate installers did not
have this ability before.

This is only allowed at install-time- not afterward.

Bug: 24746231
Change-Id: Ia0ec290bb0bcde1d8137c188e2667cb7718dbfd7
diff --git a/api/current.txt b/api/current.txt
index abc9e9a..2b8d0ab 100644
--- a/api/current.txt
+++ b/api/current.txt
@@ -5886,6 +5886,7 @@
     method public boolean hasGrantedPolicy(android.content.ComponentName, int);
     method public boolean installCaCert(android.content.ComponentName, byte[]);
     method public boolean installKeyPair(android.content.ComponentName, java.security.PrivateKey, java.security.cert.Certificate, java.lang.String);
+    method public boolean installKeyPair(android.content.ComponentName, java.security.PrivateKey, java.security.cert.Certificate, java.lang.String, boolean);
     method public boolean isActivePasswordSufficient();
     method public boolean isAdminActive(android.content.ComponentName);
     method public boolean isApplicationHidden(android.content.ComponentName, java.lang.String);
diff --git a/api/system-current.txt b/api/system-current.txt
index b36d7e8..5a3d8de 100644
--- a/api/system-current.txt
+++ b/api/system-current.txt
@@ -6031,6 +6031,7 @@
     method public boolean hasGrantedPolicy(android.content.ComponentName, int);
     method public boolean installCaCert(android.content.ComponentName, byte[]);
     method public boolean installKeyPair(android.content.ComponentName, java.security.PrivateKey, java.security.cert.Certificate, java.lang.String);
+    method public boolean installKeyPair(android.content.ComponentName, java.security.PrivateKey, java.security.cert.Certificate, java.lang.String, boolean);
     method public boolean isActivePasswordSufficient();
     method public boolean isAdminActive(android.content.ComponentName);
     method public boolean isApplicationHidden(android.content.ComponentName, java.lang.String);
diff --git a/api/test-current.txt b/api/test-current.txt
index 3878fbf..1e432dc 100644
--- a/api/test-current.txt
+++ b/api/test-current.txt
@@ -5888,6 +5888,7 @@
     method public boolean hasGrantedPolicy(android.content.ComponentName, int);
     method public boolean installCaCert(android.content.ComponentName, byte[]);
     method public boolean installKeyPair(android.content.ComponentName, java.security.PrivateKey, java.security.cert.Certificate, java.lang.String);
+    method public boolean installKeyPair(android.content.ComponentName, java.security.PrivateKey, java.security.cert.Certificate, java.lang.String, boolean);
     method public boolean isActivePasswordSufficient();
     method public boolean isAdminActive(android.content.ComponentName);
     method public boolean isApplicationHidden(android.content.ComponentName, java.lang.String);
diff --git a/core/java/android/app/admin/DevicePolicyManager.java b/core/java/android/app/admin/DevicePolicyManager.java
index ae63a2f..cbb6732 100644
--- a/core/java/android/app/admin/DevicePolicyManager.java
+++ b/core/java/android/app/admin/DevicePolicyManager.java
@@ -2677,8 +2677,16 @@
     }
 
     /**
-     * Called by a device or profile owner to install a certificate and private key pair. The
-     * keypair will be visible to all apps within the profile.
+     * Called by a device or profile owner, or delegated certificate installer, to install a
+     * certificate and corresponding private key. All apps within the profile will be able to access
+     * the certificate and use the private key, given direct user approval.
+     *
+     * <p>Access to the installed credentials will not be granted to the caller of this API without
+     * direct user approval. This is for security - should a certificate installer become
+     * compromised, certificates it had already installed will be protected.
+     *
+     * <p>If the installer must have access to the credentials, call
+     * {@link #installKeyPair(ComponentName, PrivateKey, Certificate, String, boolean)} instead.
      *
      * @param admin Which {@link DeviceAdminReceiver} this request is associated with, or
      *            {@code null} if calling from a delegated certificate installer.
@@ -2690,11 +2698,35 @@
      */
     public boolean installKeyPair(@Nullable ComponentName admin, @NonNull PrivateKey privKey,
             @NonNull Certificate cert, @NonNull String alias) {
+        return installKeyPair(admin, privKey, cert, alias, false);
+    }
+
+    /**
+     * Called by a device or profile owner, or delegated certificate installer, to install a
+     * certificate and corresponding private key. All apps within the profile will be able to access
+     * the certificate and use the private key, given direct user approval.
+     *
+     * <p>The caller of this API may grant itself access to the credential immediately, without user
+     * approval. It is a best practice not to request this unless strictly necessary since it opens
+     * up additional security vulnerabilities.
+     *
+     * @param admin Which {@link DeviceAdminReceiver} this request is associated with, or
+     *            {@code null} if calling from a delegated certificate installer.
+     * @param privKey The private key to install.
+     * @param cert The certificate to install.
+     * @param alias The private key alias under which to install the certificate. If a certificate
+     * with that alias already exists, it will be overwritten.
+     * @param requestAccess {@code true} to request that the calling app be granted access to the
+     * credentials immediately. Otherwise, access to the credentials will be gated by user approval.
+     * @return {@code true} if the keys were installed, {@code false} otherwise.
+     */
+    public boolean installKeyPair(@Nullable ComponentName admin, @NonNull PrivateKey privKey,
+            @NonNull Certificate cert, @NonNull String alias, boolean requestAccess) {
         try {
             final byte[] pemCert = Credentials.convertToPem(cert);
             final byte[] pkcs8Key = KeyFactory.getInstance(privKey.getAlgorithm())
                     .getKeySpec(privKey, PKCS8EncodedKeySpec.class).getEncoded();
-            return mService.installKeyPair(admin, pkcs8Key, pemCert, alias);
+            return mService.installKeyPair(admin, pkcs8Key, pemCert, alias, requestAccess);
         } catch (RemoteException e) {
             Log.w(TAG, REMOTE_EXCEPTION_MESSAGE, e);
         } catch (NoSuchAlgorithmException | InvalidKeySpecException e) {
@@ -2706,8 +2738,8 @@
     }
 
     /**
-     * Called by a device or profile owner to remove all user credentials installed under a given
-     * alias.
+     * Called by a device or profile owner, or delegated certificate installer, to remove all user
+     * credentials installed under a given alias.
      *
      * @param admin Which {@link DeviceAdminReceiver} this request is associated with, or
      *            {@code null} if calling from a delegated certificate installer.
diff --git a/core/java/android/app/admin/IDevicePolicyManager.aidl b/core/java/android/app/admin/IDevicePolicyManager.aidl
index e9af872..c6dd01b 100644
--- a/core/java/android/app/admin/IDevicePolicyManager.aidl
+++ b/core/java/android/app/admin/IDevicePolicyManager.aidl
@@ -145,7 +145,8 @@
     void uninstallCaCerts(in ComponentName admin, in String[] aliases);
     void enforceCanManageCaCerts(in ComponentName admin);
 
-    boolean installKeyPair(in ComponentName who, in byte[] privKeyBuffer, in byte[] certBuffer, String alias);
+    boolean installKeyPair(in ComponentName who, in byte[] privKeyBuffer, in byte[] certBuffer,
+            String alias, boolean requestAccess);
     boolean removeKeyPair(in ComponentName who, String alias);
     void choosePrivateKeyAlias(int uid, in Uri uri, in String alias, IBinder aliasCallback);
 
diff --git a/services/devicepolicy/java/com/android/server/devicepolicy/DevicePolicyManagerService.java b/services/devicepolicy/java/com/android/server/devicepolicy/DevicePolicyManagerService.java
index 33225eb..d01af1a 100644
--- a/services/devicepolicy/java/com/android/server/devicepolicy/DevicePolicyManagerService.java
+++ b/services/devicepolicy/java/com/android/server/devicepolicy/DevicePolicyManagerService.java
@@ -4090,16 +4090,24 @@
     }
 
     @Override
-    public boolean installKeyPair(ComponentName who, byte[] privKey, byte[] cert, String alias) {
+    public boolean installKeyPair(ComponentName who, byte[] privKey, byte[] cert, String alias,
+            boolean requestAccess) {
         enforceCanManageInstalledKeys(who);
 
-        final UserHandle userHandle = new UserHandle(UserHandle.getCallingUserId());
+        final int callingUid = mInjector.binderGetCallingUid();
         final long id = mInjector.binderClearCallingIdentity();
         try {
-            final KeyChainConnection keyChainConnection = KeyChain.bindAsUser(mContext, userHandle);
+            final KeyChainConnection keyChainConnection =
+                    KeyChain.bindAsUser(mContext, UserHandle.getUserHandleForUid(callingUid));
             try {
                 IKeyChainService keyChain = keyChainConnection.getService();
-                return keyChain.installKeyPair(privKey, cert, alias);
+                if (!keyChain.installKeyPair(privKey, cert, alias)) {
+                    return false;
+                }
+                if (requestAccess) {
+                    keyChain.setGrant(callingUid, alias, true);
+                }
+                return true;
             } catch (RemoteException e) {
                 Log.e(LOG_TAG, "Installing certificate", e);
             } finally {