if (args.length != 6) {
System.out.println(
"Usage: Hancock -s|-v keystore storepass alias " +
"messagefile signaturefile");
return;
}
String options = args[0];
String keystorefile = args[1];
String storepass = args[2];
String alias = args[3];
String messagefile = args[4];
String signaturefile = args[5];
Signature signature = Signature.getInstance("DSA");
KeyStore keystore = KeyStore.getInstance();
keystore.load(new FileInputStream(keystorefile), storepass);
if (options.indexOf("s") != -1)
signature.initSign(keystore.getPrivateKey(alias, storepass));
else
signature.initVerify(keystore.getCertificate(alias).getPublicKey());
FileInputStream in = new FileInputStream(messagefile);
byte[] buffer = new byte[8192];
int length;
while ((length = in.read(buffer)) != -1)
signature.update(buffer, 0, length);
in.close();
if (options.indexOf("s") != -1) {
FileOutputStream out = new FileOutputStream(signaturefile);
byte[] raw = signature.sign();
out.write(raw);
out.close();
}
else {
FileInputStream sigIn = new FileInputStream(signaturefile);
byte[] raw = new byte[sigIn.available()];
sigIn.read(raw);
sigIn.close();
if (signature.verify(raw))
System.out.println("The signature is good.");
else
System.out.println("The signature is bad.");
}
