Differential D7060 Diff 23950 lib/utils/pkcs7-padding.test.js

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lib/utils/pkcs7-padding.test.js

// @flow		// @flow

import { pkcs7pad, pkcs7unpad } from './pkcs7-padding.js';		import {
		pkcs7pad,
		pkcs7unpad,
		superblockPad,
		superblockUnpad,
		} from './pkcs7-padding.js';

describe('PKCS#7 Padding', () => {		describe('PKCS#7 Padding', () => {
it('should pad data to a multiple of blockSize bytes', () => {		it('should pad data to a multiple of blockSize bytes', () => {
const blockSize = 16;		const blockSize = 16;
const data = generateRandomData(100);		const data = generateRandomData(100);
const expectedPadding = 16 - (data.length % blockSize);		const expectedPadding = 16 - (data.length % blockSize);

const padded = pkcs7pad(data, blockSize);		const padded = pkcs7pad(data, blockSize);
▲ Show 20 Lines • Show All 59 Lines • ▼ Show 20 Lines	it('pkcs7pad and pkcs7unpad should be inverses', () => {
const data = generateRandomData(100);		const data = generateRandomData(100);
const padded = pkcs7pad(data, blockSize);		const padded = pkcs7pad(data, blockSize);
const unpadded = pkcs7unpad(padded);		const unpadded = pkcs7unpad(padded);
expect(unpadded.length).toBe(data.length);		expect(unpadded.length).toBe(data.length);
expect(unpadded).toEqual(data);		expect(unpadded).toEqual(data);
});		});
});		});

		describe('superblock padding', () => {
		it('should pad data to a multiple of superblockSize blocks', () => {
		const blockSizeBytes = 16;
		const superblockSizeBlocks = 4;
		const dataLengthBytes = 3 * 16;
		const expectedPaddedLength = 4 * 16;
		const expectedBlockPadding = 1;

		const data = generateRandomData(dataLengthBytes);
		const padded = superblockPad(data, blockSizeBytes, superblockSizeBlocks);

		expect(padded.length % expectedPaddedLength).toBe(0);
		expect(padded[padded.length - 1]).toBe(expectedBlockPadding);
		});

		it('pad should add a full superblock if input is a multiple of superblockSize blocks', () => {
		const blockSizeBytes = 16;
		const superblockSizeBlocks = 4;
		const dataLengthBytes = 4 * 16;
		const expectedPaddedLength = 8 * 16;
		const expectedBlockPadding = 4;

		const data = generateRandomData(dataLengthBytes);
		const padded = superblockPad(data, blockSizeBytes, superblockSizeBlocks);

		expect(padded.length % expectedPaddedLength).toBe(0);
		expect(padded[padded.length - 1]).toBe(expectedBlockPadding);
		});

		it('superblockUnpad should unpad data', () => {
		const blockSizeBytes = 16;

		// 2 blocks of data + 2 blocks of padding = 4 blocks total (1 superblock)
		const padded = new Uint8Array([
		...generateRandomArray(2 * 16),
		...new Array(2 * 16).fill(2),
		]);

		const unpadded = superblockUnpad(padded, blockSizeBytes);

		expect(unpadded.length).toBe(32);
		expect(unpadded).toEqual(padded.subarray(0, 32));
		});

		it('superblockUnpad should throw if the padding length is 0', () => {
		const blockSizeBytes = 16;
		const padded = new Uint8Array([
		...generateRandomArray(2 * 16),
		...new Array(2 * 16).fill(0),
		]);
		expect(() => superblockUnpad(padded, blockSizeBytes)).toThrow();
		});

		it('superblockUnpad should throw if the padding length is > num blocks', () => {
		const blockSizeBytes = 16;
		// 4 blocks total, but filled with 5s
		const padded = new Uint8Array([
		...generateRandomArray(2 * 16),
		...new Array(2 * 16).fill(5),
		]);
		expect(() => superblockUnpad(padded, blockSizeBytes)).toThrow();
		});

		it('superblockUnpad should throw if the padding is invalid', () => {
		const blockSizeBytes = 16;
		const padded = new Uint8Array([
		...generateRandomArray(2 * 16),
		...generateRandomArray(2 * 15),
		...[1],
		]);
		expect(() => superblockUnpad(padded, blockSizeBytes)).toThrow();
		});
		});

function generateRandomData(length: number): Uint8Array {		function generateRandomData(length: number): Uint8Array {
const data = new Uint8Array(length);		const data = new Uint8Array(length);
for (let i = 0; i < length; i++) {		for (let i = 0; i < length; i++) {
data[i] = Math.floor(Math.random() * 256);		data[i] = Math.floor(Math.random() * 256);
}		}
return data;		return data;
}		}

function generateRandomArray(length: number): Array<number> {		function generateRandomArray(length: number): Array<number> {
return new Array(length).map(() => Math.floor(Math.random() * 256));		return new Array(length).map(() => Math.floor(Math.random() * 256));
}		}