XPlivoSignature.java

package com.plivo.helper.util;

import java.util.LinkedHashMap;
import java.util.Map;
import java.util.Map.Entry;
import java.util.TreeMap;
import javax.crypto.Mac;
import javax.crypto.spec.SecretKeySpec;
import org.apache.commons.codec.binary.Base64;

import com.plivo.helper.exception.PlivoException;

public class XPlivoSignature {
	public static Boolean verify(String uri, LinkedHashMap<String, String> parameters, String xsignature, String authToken)
		throws PlivoException {
		Boolean isMatch = false;
		Map<String, String> sortedParams = new TreeMap<String, String>(parameters);
		for ( Entry<String, String> pair : sortedParams.entrySet() )
		{
			uri += pair.getKey() + pair.getValue();
		}
		
		try {
	             byte[] keyBytes = authToken.getBytes();
	             byte[] textBytes = uri.getBytes();
	             Mac hmac = Mac.getInstance("HmacSHA1");
	             SecretKeySpec macKey =
	                 new SecretKeySpec(keyBytes, "HmacSHA1");
	             hmac.init(macKey);
	             byte[] signBytes = hmac.doFinal(textBytes);
	             String signature = new String(Base64.encodeBase64(signBytes));
	             if ( signature.equals(xsignature) )
	            	 isMatch = true;
	         } catch (Exception e) {
	             throw new PlivoException(e.getLocalizedMessage());
	         }
		
		return isMatch;
	}
}