Encrypting a string with SHA1 does not return the expected value

Question

I’m consuming a webservice of nfse (electronic service invoice), and the nfse batch receipt function, there is that the password is encrypted using the algorithm SHA1.

The Handbook exemplifies this:

The password: "1234", should look like this: cRDtpNCeBiql5KOQsKVyrA0sAiA=

I even used the code below:

public string SenhaHash(senha){
   var hash = new SHA1CryptoServiceProvider();
   var senhaBytes = Encoding.Default.GetBytes(senha);
   var senhaHash = hash.ComputeHash(senhaBytes );

   return senhaHash;
}

However the value returned is a byte array, which has nothing to do with the value I should arrive at.

Answer 1

The cRDtpNCeBiql5KOQsKVyrA0sAiA= is a Base64 of the result of SHA-1.

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Unfortunately I can’t help you with the exact code. But if you have the byte array from SHA-1, simply encode this result to Base64. I made an example of this, in another language, so it might help.

If SHA-1 is correct Base64 of the SHA-1 result will have to give the cRDtpNCeBiql5KOQsKVyrA0sAiA=. Apparently you can use the Convert.ToBase64String, to convert to correct encoding.

The correct algorithm would look like this:

public string SenhaHash(senha){
  var hash = new SHA1CryptoServiceProvider();
  var senhaBytes = Encoding.Default.GetBytes(senha);
  var senhaHash = hash.ComputeHash(senhaBytes );
  var senhaHashBase64 = Convert.ToBase64String(senhaHash);

  return senhaHash;
}