Big error screen if signature is invalid or key is revoked/expired, also fixes signature status for expired and revoked keys

OpenKeychain/src/main/java/org/sufficientlysecure/keychain/pgp/CanonicalizedKeyRing.java

@@ -25,6 +25,7 @@ import org.sufficientlysecure.keychain.util.IterableIterator;
 import java.io.IOException;
 import java.io.OutputStream;
 import java.util.ArrayList;
+import java.util.Date;
 
 /** A generic wrapped PGPKeyRing object.
  *
@@ -76,6 +77,16 @@ public abstract class CanonicalizedKeyRing extends KeyRing {
         return getRing().getPublicKey().isRevoked();
     }
 
+    public boolean isExpired() throws PgpGeneralException {
+        // Is the master key expired?
+        Date creationDate = getRing().getPublicKey().getCreationTime();
+        Date expiryDate = getRing().getPublicKey().getValidSeconds() > 0
+                ? new Date(creationDate.getTime() + getRing().getPublicKey().getValidSeconds() * 1000) : null;
+
+        Date now = new Date();
+        return creationDate.after(now) || (expiryDate != null && expiryDate.before(now));
+    }
+
     public boolean canCertify() throws PgpGeneralException {
         return getRing().getPublicKey().isEncryptionKey();
     }

OpenKeychain/src/main/java/org/sufficientlysecure/keychain/pgp/OpenPgpSignatureResultBuilder.java

@@ -103,9 +103,14 @@ public class OpenPgpSignatureResultBuilder {
         Log.d(Constants.TAG, "signingRing.getUnorderedUserIds(): " + signingRing.getUnorderedUserIds());
         setUserIds(signingRing.getUnorderedUserIds());
 
-        // from KEY
-        setKeyExpired(signingKey.isExpired());
-        setKeyRevoked(signingKey.isRevoked());
+        // either master key is expired/revoked or this specific subkey is expired/revoked
+        try {
+            setKeyExpired(signingRing.isExpired() || signingKey.isExpired());
+            setKeyRevoked(signingRing.isRevoked() || signingKey.isRevoked());
+        } catch (PgpGeneralException e) {
+            Log.e(Constants.TAG, "shouldn't happen!");
+            setKeyRevoked(true);
+        }
     }
 
     public OpenPgpSignatureResult build() {

OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/DecryptFragment.java

@@ -112,9 +112,15 @@ public abstract class DecryptFragment extends Fragment {
         startActivityForResult(intent, REQUEST_CODE_NFC_DECRYPT);
     }
 
-    protected void onResult(DecryptVerifyResult decryptVerifyResult) {
+    /**
+     *
+     * @return returns false if signature is invalid, key is revoked or expired.
+     */
+    protected boolean onResult(DecryptVerifyResult decryptVerifyResult) {
         final OpenPgpSignatureResult signatureResult = decryptVerifyResult.getSignatureResult();
 
+        boolean valid = false;
+
         mSignatureKeyId = 0;
         mResultLayout.setVisibility(View.VISIBLE);
         if (signatureResult != null) {
@@ -147,14 +153,9 @@ public abstract class DecryptFragment extends Fragment {
                     KeyFormattingUtils.setStatusImage(getActivity(), mSignatureIcon, mSignatureText, KeyFormattingUtils.STATE_VERIFIED);
 
                     setSignatureLayoutVisibility(View.VISIBLE);
-                    mSignatureAction.setText(R.string.decrypt_result_action_show);
-                    mSignatureAction.setCompoundDrawablesWithIntrinsicBounds(0, 0, R.drawable.ic_action_accounts, 0);
-                    mSignatureLayout.setOnClickListener(new View.OnClickListener() {
-                        @Override
-                        public void onClick(View v) {
-                            showKey(mSignatureKeyId);
-                        }
-                    });
+                    setShowAction(mSignatureKeyId);
+
+                    valid = true;
                     break;
                 }
 
@@ -163,25 +164,9 @@ public abstract class DecryptFragment extends Fragment {
                     KeyFormattingUtils.setStatusImage(getActivity(), mSignatureIcon, mSignatureText, KeyFormattingUtils.STATE_UNVERIFIED);
 
                     setSignatureLayoutVisibility(View.VISIBLE);
-                    setShowAction(mSignatureAction, mSignatureKeyId);
-                    break;
-                }
+                    setShowAction(mSignatureKeyId);
 
-                case OpenPgpSignatureResult.SIGNATURE_KEY_EXPIRED: {
-                    mSignatureText.setText(R.string.decrypt_result_signature_expired_key);
-                    KeyFormattingUtils.setStatusImage(getActivity(), mSignatureIcon, mSignatureText, KeyFormattingUtils.STATE_EXPIRED);
-
-                    setSignatureLayoutVisibility(View.VISIBLE);
-                    setShowAction(mSignatureAction, mSignatureKeyId);
-                    break;
-                }
-
-                case OpenPgpSignatureResult.SIGNATURE_KEY_REVOKED: {
-                    mSignatureText.setText(R.string.decrypt_result_signature_revoked_key);
-                    KeyFormattingUtils.setStatusImage(getActivity(), mSignatureIcon, mSignatureText, KeyFormattingUtils.STATE_REVOKED);
-
-                    setSignatureLayoutVisibility(View.VISIBLE);
-                    setShowAction(mSignatureAction, mSignatureKeyId);
+                    valid = true;
                     break;
                 }
 
@@ -198,6 +183,30 @@ public abstract class DecryptFragment extends Fragment {
                             lookupUnknownKey(mSignatureKeyId);
                         }
                     });
+
+                    valid = true;
+                    break;
+                }
+
+                case OpenPgpSignatureResult.SIGNATURE_KEY_EXPIRED: {
+                    mSignatureText.setText(R.string.decrypt_result_signature_expired_key);
+                    KeyFormattingUtils.setStatusImage(getActivity(), mSignatureIcon, mSignatureText, KeyFormattingUtils.STATE_EXPIRED);
+
+                    setSignatureLayoutVisibility(View.VISIBLE);
+                    setShowAction(mSignatureKeyId);
+
+                    valid = false;
+                    break;
+                }
+
+                case OpenPgpSignatureResult.SIGNATURE_KEY_REVOKED: {
+                    mSignatureText.setText(R.string.decrypt_result_signature_revoked_key);
+                    KeyFormattingUtils.setStatusImage(getActivity(), mSignatureIcon, mSignatureText, KeyFormattingUtils.STATE_REVOKED);
+
+                    setSignatureLayoutVisibility(View.VISIBLE);
+                    setShowAction(mSignatureKeyId);
+
+                    valid = false;
                     break;
                 }
 
@@ -206,6 +215,8 @@ public abstract class DecryptFragment extends Fragment {
                     KeyFormattingUtils.setStatusImage(getActivity(), mSignatureIcon, mSignatureText, KeyFormattingUtils.STATE_INVALID);
 
                     setSignatureLayoutVisibility(View.GONE);
+
+                    valid = false;
                     break;
                 }
             }
@@ -216,7 +227,11 @@ public abstract class DecryptFragment extends Fragment {
             KeyFormattingUtils.setStatusImage(getActivity(), mSignatureIcon, mSignatureText, KeyFormattingUtils.STATE_NOT_SIGNED);
             mEncryptionText.setText(R.string.decrypt_result_encrypted);
             KeyFormattingUtils.setStatusImage(getActivity(), mEncryptionIcon, mEncryptionText, KeyFormattingUtils.STATE_ENCRYPTED);
+
+            valid = true;
         }
+
+        return valid;
     }
 
     private void setSignatureLayoutVisibility(int visibility) {
@@ -225,10 +240,10 @@ public abstract class DecryptFragment extends Fragment {
         mSignatureDivider2.setVisibility(visibility);
     }
 
-    private void setShowAction(TextView signatureAction, final long signatureKeyId) {
-        signatureAction.setText(R.string.decrypt_result_action_show);
-        signatureAction.setCompoundDrawablesWithIntrinsicBounds(0, 0, R.drawable.ic_action_accounts, 0);
-        signatureAction.setOnClickListener(new View.OnClickListener() {
+    private void setShowAction(final long signatureKeyId) {
+        mSignatureAction.setText(R.string.decrypt_result_action_show);
+        mSignatureAction.setCompoundDrawablesWithIntrinsicBounds(0, 0, R.drawable.ic_action_accounts, 0);
+        mSignatureLayout.setOnClickListener(new View.OnClickListener() {
             @Override
             public void onClick(View v) {
                 showKey(signatureKeyId);

OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/DecryptTextFragment.java

@@ -27,6 +27,8 @@ import android.text.method.ScrollingMovementMethod;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
+import android.widget.Button;
+import android.widget.LinearLayout;
 import android.widget.TextView;
 
 import org.openintents.openpgp.util.OpenPgpApi;
@@ -44,6 +46,9 @@ public class DecryptTextFragment extends DecryptFragment {
     public static final String ARG_CIPHERTEXT = "ciphertext";
 
     // view
+    private LinearLayout mValidLayout;
+    private LinearLayout mInvalidLayout;
+    private Button mInvalidButton;
     private TextView mText;
     private View mShareButton;
     private View mCopyButton;
@@ -71,7 +76,9 @@ public class DecryptTextFragment extends DecryptFragment {
     @Override
     public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
         View view = inflater.inflate(R.layout.decrypt_text_fragment, container, false);
-
+        mValidLayout = (LinearLayout) view.findViewById(R.id.decrypt_text_valid);
+        mInvalidLayout = (LinearLayout) view.findViewById(R.id.decrypt_text_invalid);
+        mInvalidButton = (Button) view.findViewById(R.id.decrypt_text_invalid_button);
         mText = (TextView) view.findViewById(R.id.decrypt_text_plaintext);
         mShareButton = view.findViewById(R.id.action_decrypt_share_plaintext);
         mCopyButton = view.findViewById(R.id.action_decrypt_copy_plaintext);
@@ -87,6 +94,13 @@ public class DecryptTextFragment extends DecryptFragment {
                 copyToClipboard(mText.getText().toString());
             }
         });
+        mInvalidButton.setOnClickListener(new View.OnClickListener() {
+            @Override
+            public void onClick(View v) {
+                mInvalidLayout.setVisibility(View.GONE);
+                mValidLayout.setVisibility(View.VISIBLE);
+            }
+        });
 
         return view;
     }
@@ -186,9 +200,18 @@ public class DecryptTextFragment extends DecryptFragment {
                         pgpResult.createNotify(getActivity()).show();
 
                         // display signature result in activity
-                        onResult(pgpResult);
+                        boolean valid = onResult(pgpResult);
+
+                        if (valid) {
+                            mInvalidLayout.setVisibility(View.GONE);
+                            mValidLayout.setVisibility(View.VISIBLE);
+                        } else {
+                            mInvalidLayout.setVisibility(View.VISIBLE);
+                            mValidLayout.setVisibility(View.GONE);
+                        }
                     } else {
                         pgpResult.createNotify(getActivity()).show();
+                        // TODO: show also invalid layout with different text?
                     }
                 }
             }

OpenKeychain/src/main/res/layout/decrypt_text_fragment.xml

@@ -6,73 +6,109 @@
 
     <include layout="@layout/decrypt_result_include" />
 
-    <ScrollView
-        android:fillViewport="true"
-        android:paddingTop="8dp"
-        android:layout_width="match_parent"
-        android:scrollbars="vertical"
-        android:layout_height="0dp"
-        android:layout_weight="1">
-
-        <TextView
-            android:id="@+id/decrypt_text_plaintext"
-            android:paddingLeft="16dp"
-            android:paddingRight="16dp"
-            android:textAppearance="?android:attr/textAppearanceMedium"
-            android:layout_width="match_parent"
-            android:layout_height="wrap_content"
-            android:gravity="top"
-            android:hint=""
-            android:textIsSelectable="true" />
-
-    </ScrollView>
-
-    <View
-        android:layout_width="match_parent"
-        android:layout_height="1dip"
-        android:layout_marginLeft="16dp"
-        android:layout_marginRight="16dp"
-        android:background="?android:attr/listDivider" />
-
     <LinearLayout
-        android:id="@+id/action_decrypt_share_plaintext"
+        android:visibility="gone"
+        android:id="@+id/decrypt_text_valid"
         android:layout_width="match_parent"
-        android:layout_height="wrap_content"
-        android:layout_marginLeft="16dp"
-        android:layout_marginRight="16dp"
-        android:clickable="true"
-        style="@style/SelectableItem"
-        android:orientation="horizontal">
+        android:layout_height="match_parent"
+        android:orientation="vertical">
 
-        <TextView
-            android:paddingLeft="8dp"
-            android:paddingRight="8dp"
-            android:textAppearance="?android:attr/textAppearanceMedium"
-            android:layout_width="0dp"
-            android:layout_height="wrap_content"
-            android:minHeight="?android:attr/listPreferredItemHeight"
-            android:text="@string/btn_add_share_decrypted_text"
-            android:drawableRight="@drawable/ic_action_share"
-            android:drawablePadding="8dp"
-            android:gravity="center_vertical"
-            android:layout_weight="1" />
+        <ScrollView
+            android:fillViewport="true"
+            android:paddingTop="8dp"
+            android:layout_width="match_parent"
+            android:scrollbars="vertical"
+            android:layout_height="0dp"
+            android:layout_weight="1">
+
+            <TextView
+                android:id="@+id/decrypt_text_plaintext"
+                android:paddingLeft="16dp"
+                android:paddingRight="16dp"
+                android:textAppearance="?android:attr/textAppearanceMedium"
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:gravity="top"
+                android:hint=""
+                android:textIsSelectable="true" />
+
+        </ScrollView>
 
         <View
-            android:layout_width="1dip"
-            android:layout_height="match_parent"
-            android:gravity="right"
-            android:layout_marginBottom="8dp"
-            android:layout_marginTop="8dp"
+            android:layout_width="match_parent"
+            android:layout_height="1dip"
+            android:layout_marginLeft="16dp"
+            android:layout_marginRight="16dp"
             android:background="?android:attr/listDivider" />
 
-        <ImageButton
-            android:id="@+id/action_decrypt_copy_plaintext"
-            android:layout_width="wrap_content"
-            android:layout_height="match_parent"
-            android:padding="8dp"
-            android:src="@drawable/ic_action_copy"
-            android:layout_gravity="center_vertical"
-            style="@style/SelectableItem" />
+        <LinearLayout
+            android:id="@+id/action_decrypt_share_plaintext"
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:layout_marginLeft="16dp"
+            android:layout_marginRight="16dp"
+            android:clickable="true"
+            style="@style/SelectableItem"
+            android:orientation="horizontal">
+
+            <TextView
+                android:paddingLeft="8dp"
+                android:paddingRight="8dp"
+                android:textAppearance="?android:attr/textAppearanceMedium"
+                android:layout_width="0dp"
+                android:layout_height="wrap_content"
+                android:minHeight="?android:attr/listPreferredItemHeight"
+                android:text="@string/btn_add_share_decrypted_text"
+                android:drawableRight="@drawable/ic_action_share"
+                android:drawablePadding="8dp"
+                android:gravity="center_vertical"
+                android:layout_weight="1" />
+
+            <View
+                android:layout_width="1dip"
+                android:layout_height="match_parent"
+                android:gravity="right"
+                android:layout_marginBottom="8dp"
+                android:layout_marginTop="8dp"
+                android:background="?android:attr/listDivider" />
+
+            <ImageButton
+                android:id="@+id/action_decrypt_copy_plaintext"
+                android:layout_width="wrap_content"
+                android:layout_height="match_parent"
+                android:padding="8dp"
+                android:src="@drawable/ic_action_copy"
+                android:layout_gravity="center_vertical"
+                style="@style/SelectableItem" />
+
+        </LinearLayout>
 
     </LinearLayout>
+
+    <LinearLayout
+        android:visibility="gone"
+        android:id="@+id/decrypt_text_invalid"
+        android:layout_width="wrap_content"
+        android:layout_height="match_parent"
+        android:orientation="vertical"
+        android:gravity="center_vertical">
+
+        <TextView
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:textAppearance="?android:attr/textAppearanceMedium"
+            android:text="@string/decrypt_invalid_text"
+            android:padding="8dp"
+            android:layout_gravity="center"
+            android:textColor="@color/android_red_dark" />
+
+        <Button
+            android:id="@+id/decrypt_text_invalid_button"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:background="@drawable/button_edgy"
+            android:textColor="@color/android_red_dark"
+            android:text="@string/decrypt_invalid_button"
+            android:layout_gravity="center_horizontal" />
+    </LinearLayout>
 </LinearLayout>

OpenKeychain/src/main/res/values/strings.xml

@@ -277,6 +277,8 @@
     <string name="decrypt_result_not_encrypted">"Not Encrypted"</string>
     <string name="decrypt_result_action_show">"Show"</string>
     <string name="decrypt_result_action_Lookup">"Lookup"</string>
+    <string name="decrypt_invalid_text">"Either the signature is invalid or the key has been revoked/is expired. You can not be sure who wrote the text. Do you still want to display it?"</string>
+    <string name="decrypt_invalid_button">"I understand the risks, display it!"</string>
 
     <!-- Add keys -->
     <string name="add_keys_section_secure_exchange">"Exchange"</string>