test-padding.js

'use strict';

var nodeunit = require('nodeunit');

var aes = require('../index.js');

function bufferEqual(a, b) {
    if (a.length != b.length) { return false; }
    for (var i = 0; i < a.length; i++) {
        if (a[i] !== b[i]) { return false; }
    }
    return true;
}

module.exports = {
    "test-padding": function(test) {
        for (var size = 0; size < 100; size++) {

            // Create a random piece of data
            var data = [];
            for (var i = 0; i < size; i++) { data.push(42); }

            // Pad it
            var padded = aes.padding.pkcs7.pad(data);
            test.ok((padded.length % 16) === 0, "Failed to pad to block size");
            test.ok(data.length <= padded.length && padded.length <= data.length + 16, "Padding went awry");
            test.ok(padded[padded.length - 1] >= 1 && padded[padded.length - 1] <= 16, "Failed to pad to block size");

            // Trim it
            var trimmed = aes.padding.pkcs7.strip(padded);
            test.ok(bufferEqual(data, trimmed), "Failed to trim to original data");
        }
        test.done();
    }
}