Java SHA1withRSA verification is always false, why?

Question

I'm doing a SHA1withRSA verification method but the result is always false, is it something I coded wrong or are the public keys wrong or something?

Here's the code:

Signature signature = Signature.getInstance("SHA1withRSA");
File file = this.getPublicKey();
byte[] keyBytes = Files.readAllBytes(file.toPath());

// Setup RSA key
X509EncodedKeySpec pubKeySpec = new X509EncodedKeySpec(keyBytes);
KeyFactory keyFactory = KeyFactory.getInstance("RSA");
RSAPublicKey publicKey = (RSAPublicKey) keyFactory.generatePublic(pubKeySpec);

// verify signatures
byte[] signatureBytes = Base64.decodeBase64(this.firmaB64);
signature.initVerify(publicKey);
signature.update(this.parteFirmada.getBytes());
boolean result = signature.verify(signatureBytes);

Thanks a lot!

Answer 1

I found that the string that I was verifying was not as the original string that was signed and hence that it was false. The verification code was good in case anyone is interested.

The string contained a timestamp and to pass the timestamp verification it was changed... that could never pass as verified!

Thanks for all the comments