Add pwdf retry logic to OpenSSHKeyV1KeyFile

src/main/java/com/hierynomus/sshj/common/KeyDecryptionFailedException.java

@@ -0,0 +1,38 @@
+/*
+ * Copyright (C)2009 - SSHJ Contributors
+ *
+ * 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 com.hierynomus.sshj.common;
+
+import org.bouncycastle.openssl.EncryptionException;
+
+import java.io.IOException;
+
+/**
+ * Thrown when a key file could not be decrypted correctly, e.g. if its checkInts differed in the case of an OpenSSH
+ * key file.
+ */
+public class KeyDecryptionFailedException extends IOException {
+
+    public static final String MESSAGE = "Decryption of the key failed. A supplied passphrase may be incorrect.";
+
+    public KeyDecryptionFailedException() {
+        super(MESSAGE);
+    }
+
+    public KeyDecryptionFailedException(EncryptionException cause) {
+        super(MESSAGE, cause);
+    }
+
+}

src/main/java/com/hierynomus/sshj/userauth/keyprovider/OpenSSHKeyV1KeyFile.java

@@ -15,6 +15,7 @@
  */
 package com.hierynomus.sshj.userauth.keyprovider;
 
+import com.hierynomus.sshj.common.KeyDecryptionFailedException;
 import com.hierynomus.sshj.transport.cipher.BlockCiphers;
 import net.i2p.crypto.eddsa.EdDSAPrivateKey;
 import net.i2p.crypto.eddsa.spec.EdDSANamedCurveTable;
@@ -111,8 +112,16 @@ private KeyPair readDecodedKeyPair(final PlainBuffer keyBuffer) throws IOExcepti
             return readUnencrypted(privateKeyBuffer, publicKey);
         } else {
             logger.info("Keypair is encrypted with: " + cipherName + ", " + kdfName + ", " + Arrays.toString(kdfOptions));
-            PlainBuffer decrypted = decryptBuffer(privateKeyBuffer, cipherName, kdfName, kdfOptions);
-            return readUnencrypted(decrypted, publicKey);
+            while (true) {
+                PlainBuffer decryptionBuffer = new PlainBuffer(privateKeyBuffer);
+                PlainBuffer decrypted = decryptBuffer(decryptionBuffer, cipherName, kdfName, kdfOptions);
+                try {
+                    return readUnencrypted(decrypted, publicKey);
+                } catch (KeyDecryptionFailedException e) {
+                    if (pwdf == null || !pwdf.shouldRetry(resource))
+                        throw e;
+                }
+            }
 //            throw new IOException("Cannot read encrypted keypair with " + cipherName + " yet.");
         }
     }
@@ -184,7 +193,7 @@ private KeyPair readUnencrypted(final PlainBuffer keyBuffer, final PublicKey pub
         int checkInt1 = keyBuffer.readUInt32AsInt(); // uint32 checkint1
         int checkInt2 = keyBuffer.readUInt32AsInt(); // uint32 checkint2
         if (checkInt1 != checkInt2) {
-            throw new IOException("The checkInts differed, the key was not correctly decoded.");
+            throw new KeyDecryptionFailedException();
         }
         // The private key section contains both the public key and the private key
         String keyType = keyBuffer.readString(); // string keytype

src/main/java/net/schmizz/sshj/userauth/keyprovider/PKCS8KeyFile.java

@@ -15,6 +15,7 @@
  */
 package net.schmizz.sshj.userauth.keyprovider;
 
+import com.hierynomus.sshj.common.KeyDecryptionFailedException;
 import net.schmizz.sshj.common.IOUtils;
 import net.schmizz.sshj.common.SecurityUtils;
 import net.schmizz.sshj.userauth.password.PasswordUtils;
@@ -85,7 +86,7 @@ protected KeyPair readKeyPair()
                 if (pwdf != null && pwdf.shouldRetry(resource))
                     continue;
                 else
-                    throw e;
+                    throw new KeyDecryptionFailedException(e);
             } finally {
                 IOUtils.closeQuietly(r);
             }

src/test/java/net/schmizz/sshj/keyprovider/OpenSSHKeyFileTest.java

@@ -15,6 +15,7 @@
  */
 package net.schmizz.sshj.keyprovider;
 
+import com.hierynomus.sshj.common.KeyDecryptionFailedException;
 import com.hierynomus.sshj.userauth.certificate.Certificate;
 import com.hierynomus.sshj.userauth.keyprovider.OpenSSHKeyV1KeyFile;
 import net.schmizz.sshj.common.KeyType;
@@ -200,12 +201,34 @@ public void shouldLoadED25519PrivateKey() throws IOException {
 
     @Test
     public void shouldLoadProtectedED25519PrivateKeyAes256CTR() throws IOException {
-        checkOpenSSHKeyV1("src/test/resources/keytypes/ed25519_protected", "sshjtest");
+        checkOpenSSHKeyV1("src/test/resources/keytypes/ed25519_protected", "sshjtest", false);
+        checkOpenSSHKeyV1("src/test/resources/keytypes/ed25519_protected", "sshjtest", true);
     }
 
     @Test
     public void shouldLoadProtectedED25519PrivateKeyAes256CBC() throws IOException {
-        checkOpenSSHKeyV1("src/test/resources/keytypes/ed25519_aes256cbc.pem", "foobar");
+        checkOpenSSHKeyV1("src/test/resources/keytypes/ed25519_aes256cbc.pem", "foobar", false);
+        checkOpenSSHKeyV1("src/test/resources/keytypes/ed25519_aes256cbc.pem", "foobar", true);
+    }
+
+    @Test(expected = KeyDecryptionFailedException.class)
+    public void shouldFailOnIncorrectPassphraseAfterRetries() throws IOException {
+        OpenSSHKeyV1KeyFile keyFile = new OpenSSHKeyV1KeyFile();
+        keyFile.init(new File("src/test/resources/keytypes/ed25519_aes256cbc.pem"), new PasswordFinder() {
+            private int reqCounter = 0;
+
+            @Override
+            public char[] reqPassword(Resource<?> resource) {
+                reqCounter++;
+                return "incorrect".toCharArray();
+            }
+
+            @Override
+            public boolean shouldRetry(Resource<?> resource) {
+                return reqCounter <= 3;
+            }
+        });
+        keyFile.getPrivate();
     }
 
     @Test
@@ -224,17 +247,25 @@ public void shouldLoadECDSAPrivateKeyAsOpenSSHV1() throws IOException {
         assertThat(aPrivate.getAlgorithm(), equalTo("ECDSA"));
     }
 
-    private void checkOpenSSHKeyV1(String key, final String password) throws IOException {
+    private void checkOpenSSHKeyV1(String key, final String password, boolean withRetry) throws IOException {
         OpenSSHKeyV1KeyFile keyFile = new OpenSSHKeyV1KeyFile();
         keyFile.init(new File(key), new PasswordFinder() {
+            private int reqCounter = 0;
+
             @Override
             public char[] reqPassword(Resource<?> resource) {
-                return password.toCharArray();
+                if (withRetry && reqCounter < 3) {
+                    reqCounter++;
+                    // Return an incorrect password three times before returning the correct one.
+                    return (password + "incorrect").toCharArray();
+                } else {
+                    return password.toCharArray();
+                }
             }
 
             @Override
             public boolean shouldRetry(Resource<?> resource) {
-                return false;
+                return withRetry && reqCounter <= 3;
             }
         });
         PrivateKey aPrivate = keyFile.getPrivate();