Sith/doc/Kit_E-transactions_internet_premium_PHP/Exemple.php/SignVer.java

64 lines
2.3 KiB
Java

package signver;
import java.security.interfaces.RSAPublicKey;
import java.security.Signature;
import java.security.KeyFactory;
import java.security.spec.X509EncodedKeySpec;
import java.io.FileInputStream;
import java.io.DataInputStream;
import org.apache.commons.codec.binary.Base64;
import org.apache.commons.codec.net.URLCodec;
public class SignVer {
// verification signature RSA des donnees avec cle publique
private static boolean verify( byte[] dataBytes, byte[] sigBytes, String sigAlg, RSAPublicKey pubKey) throws Exception
{
Signature sig = Signature.getInstance(sigAlg);
sig.initVerify(pubKey);
sig.update(dataBytes);
return sig.verify(sigBytes);
}
// chargement de la cle AU FORMAT der :
// openssl rsa -inform PEM -in pbx_pubkey.pem -outform DER -pubin -out /tmp/pubkey.der
private static RSAPublicKey getPubKey(String pubKeyFile) throws Exception
{
FileInputStream fis = new FileInputStream(pubKeyFile);
DataInputStream dis = new DataInputStream(fis);
byte[] pubKeyBytes = new byte[fis.available()];
dis.readFully(pubKeyBytes);
fis.close();
dis.close();
KeyFactory keyFactory = KeyFactory.getInstance("RSA");
// extraction cle
X509EncodedKeySpec pubSpec = new X509EncodedKeySpec(pubKeyBytes);
RSAPublicKey pubKey = (RSAPublicKey) keyFactory.generatePublic(pubSpec);
return pubKey;
}
// exemple de verification de la signature
public static void main(String[] unused) throws Exception {
String sData = ""; // donnees signees URL encodees
String sSig = ""; // signature Base64 et URL encodee
// decodage ...
byte[] dataBytes = URLCodec.decodeUrl(sData.getBytes());
byte[] sigBytes = Base64.decodeBase64( URLCodec.decodeUrl(sSig.getBytes()));
// lecture de la cle publique
RSAPublicKey pubK = getPubKey("/tmp/pubkey.der");
// verification signature
boolean result = verify(dataBytes, sigBytes, "SHA1withRSA", pubK);
// affichage resultat
System.out.println("Resultat de la verification de signature : " + result);
}
}