implemented keychain access on OS X

main/keychain/src/main/java/org/cryptomator/keychain/MacSystemKeychainAccess.java

@@ -1,45 +1,41 @@
 package org.cryptomator.keychain;
 
-import java.io.IOException;
-import java.security.GeneralSecurityException;
-import java.security.KeyStore;
+import java.nio.CharBuffer;
 
 import javax.inject.Inject;
 import javax.inject.Singleton;
 
 import org.apache.commons.lang3.SystemUtils;
+import org.cryptomator.jni.JniModule;
+import org.cryptomator.jni.MacKeychainAccess;
 
 @Singleton
 class MacSystemKeychainAccess implements KeychainAccessStrategy {
 
-	private final KeyStore keyStore;
+	private final MacKeychainAccess keychain;
 
 	@Inject
 	public MacSystemKeychainAccess() {
-		KeyStore ks;
-		try {
-			ks = KeyStore.getInstance("KeychainStore", "Apple");
-			ks.load(null);
-		} catch (GeneralSecurityException | IOException e) {
-			ks = null;
+		if (JniModule.macFunctions().isPresent()) {
+			this.keychain = JniModule.macFunctions().get().getKeychainAccess();
+		} else {
+			this.keychain = null;
 		}
-		this.keyStore = ks;
 	}
 
 	@Override
 	public void storePassphrase(String key, CharSequence passphrase) {
-		// TODO Auto-generated method stub
+		keychain.storePassword(key, passphrase);
 	}
 
 	@Override
 	public CharSequence loadPassphrase(String key) {
-		// TODO Auto-generated method stub
-		return null;
+		return CharBuffer.wrap(keychain.loadPassword(key));
 	}
 
 	@Override
 	public boolean isSupported() {
-		return SystemUtils.IS_OS_MAC_OSX && keyStore != null;
+		return SystemUtils.IS_OS_MAC_OSX && keychain != null;
 	}
 
 }