X-Git-Url: https://git.opendaylight.org/gerrit/gitweb?a=blobdiff_plain;f=opendaylight%2Fnetconf%2Fnetconf-ssh%2Fsrc%2Fmain%2Fjava%2Forg%2Fopendaylight%2Fcontroller%2Fnetconf%2Fssh%2Fauthentication%2FPEMGenerator.java;h=53ab8219ee9c2a9f98e144f8c125f45b86edb002;hb=48814d6a264b8f13e5db1422336d9ef25cb05fa9;hp=73886c4f461eb3ecd60710da40cf6fc3ff361e54;hpb=33aa42c3375a40d417fa0612249c8831c8066473;p=controller.git

diff --git a/opendaylight/netconf/netconf-ssh/src/main/java/org/opendaylight/controller/netconf/ssh/authentication/PEMGenerator.java b/opendaylight/netconf/netconf-ssh/src/main/java/org/opendaylight/controller/netconf/ssh/authentication/PEMGenerator.java
index 73886c4f46..53ab8219ee 100644
--- a/opendaylight/netconf/netconf-ssh/src/main/java/org/opendaylight/controller/netconf/ssh/authentication/PEMGenerator.java
+++ b/opendaylight/netconf/netconf-ssh/src/main/java/org/opendaylight/controller/netconf/ssh/authentication/PEMGenerator.java
@@ -8,7 +8,11 @@
 
 package org.opendaylight.controller.netconf.ssh.authentication;
 
+import com.google.common.annotations.VisibleForTesting;
+import java.io.FileInputStream;
+import java.security.NoSuchAlgorithmException;
 import org.apache.commons.io.FileUtils;
+import org.apache.commons.io.IOUtils;
 import org.bouncycastle.openssl.PEMWriter;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -25,17 +29,55 @@ public class PEMGenerator {
     private static final Logger logger = LoggerFactory.getLogger(PEMGenerator.class);
     private static final int KEY_SIZE = 4096;
 
-    public static String generateTo(File privateFile) throws Exception {
+
+    public static String readOrGeneratePK(File privateKeyFile) throws IOException {
+        if (privateKeyFile.exists() == false) {
+            // generate & save to file
+            try {
+                return generateTo(privateKeyFile);
+            } catch (Exception e) {
+                logger.error("Exception occurred while generating PEM string to {}", privateKeyFile, e);
+                throw new IllegalStateException("Error generating RSA key from file " + privateKeyFile);
+            }
+        } else {
+            // read from file
+            try (FileInputStream fis = new FileInputStream(privateKeyFile)) {
+                return IOUtils.toString(fis);
+            } catch (final IOException e) {
+                logger.error("Error reading RSA key from file {}", privateKeyFile, e);
+                throw new IOException("Error reading RSA key from file " + privateKeyFile, e);
+            }
+        }
+    }
+
+    /**
+     * Generate private key to a file and return its content as string.
+     *
+     * @param privateFile path where private key should be generated
+     * @return String representation of private key
+     * @throws IOException
+     * @throws NoSuchAlgorithmException
+     */
+    @VisibleForTesting
+    public static String generateTo(File privateFile) throws IOException, NoSuchAlgorithmException {
+        logger.info("Generating private key to {}", privateFile.getAbsolutePath());
+        String privatePEM = generate();
+        FileUtils.write(privateFile, privatePEM);
+        return privatePEM;
+    }
+
+    @VisibleForTesting
+    public static String generate() throws NoSuchAlgorithmException, IOException {
         KeyPairGenerator keyGen = KeyPairGenerator.getInstance("RSA");
         SecureRandom sr = new SecureRandom();
         keyGen.initialize(KEY_SIZE, sr);
         KeyPair keypair = keyGen.generateKeyPair();
-        logger.info("Generating private key to {}", privateFile.getAbsolutePath());
-        String privatePEM = toString(keypair.getPrivate());
-        FileUtils.write(privateFile, privatePEM);
-        return privatePEM;
+        return toString(keypair.getPrivate());
     }
 
+    /**
+     * Get string representation of a key.
+     */
     private static String toString(Key key) throws IOException {
         try (StringWriter writer = new StringWriter()) {
             try (PEMWriter pemWriter = new PEMWriter(writer)) {
@@ -44,4 +86,5 @@ public class PEMGenerator {
             return writer.toString();
         }
     }
+
 }