Encrypter/Encrypter/Extensions.cs

using System;
using System.Collections.Generic;
using System.IO;
using System.Text;
using System.Threading.Tasks;

namespace Encrypter
{
    public static class Extensions
    {
        /// <summary>
        /// Encrypts this string by means of AES. The result gets base64 encoded.
        /// Due to the necessary millions of SHA512 iterations, the methods runs at least several seconds in the year 2020 (approx. 5-7s).
        /// This method suits for small data such as telegrams, JSON data, text notes, passwords, etc. For larger
        /// data, might use the stream overload. Rule of thumb: If the data could be stored three times in
        /// the present memory, this method could be used.
        /// </summary>
        /// <param name="data">This UTF8 encoded string to encrypt.</param>
        /// <param name="password">The password. Must consists of 6 chars or more.</param>
        /// <param name="iterations">The number of iterations to derive the key. Should not be adjusted. The default is secure for the current time.</param>
        /// <returns>The base64 encoded and encrypted string. The string is ASCII encoding.</returns>
        public static async Task<string> Encrypt(this string data, string password, int iterations = CryptoProcessor.ITERATIONS_YEAR_2020)
        {
            return await CryptoProcessor.Encrypt(data, password, iterations);
        }

        /// <summary>
        /// Encrypts a given input stream and writes the encrypted data to the provided output stream. A buffer stream
        /// gets used in front of the output stream. This method expects, that both streams are read-to-use e.g. the
        /// input stream is at the desired position and the output stream is writable, etc. This method disposes the
        /// internal crypto streams. Thus, the input and output streams might get disposed as well. Please note, that
        /// this method writes binary data without e.g. base64 encoding.
        ///
        /// When the task finished, the entire encryption of the input stream is done.
        /// </summary>
        /// <param name="inputStream">The desired input stream. The encryption starts at the current position.</param>
        /// <param name="outputStream">The desired output stream. The encrypted data gets written to the current position.</param>
        /// <param name="password">The encryption password.</param>
        /// <param name="iterations">The number of iterations to derive the key. Should not be adjusted. The default is secure for the current time.</param>
        public static async Task Encrypt(this Stream inputStream, Stream outputStream, string password, int iterations = CryptoProcessor.ITERATIONS_YEAR_2020)
        {
            await CryptoProcessor.Encrypt(inputStream, outputStream, password, iterations);
        }

        /// <summary>
        /// Decrypts an base64 encoded and encrypted string. Due to the necessary millions of SHA512 iterations,
        /// the methods runs at least several seconds in the year 2020 (approx. 5-7s).
        /// This method suits for small data such as telegrams, JSON data, text notes, passwords, etc. For larger
        /// data, might use the stream overload. Rule of thumb: If the data could be stored three times in
        /// the present memory, this method could be used.
        /// </summary>
        /// <param name="data">The base64 encoded and AES encrypted string. This string must be ASCII encoded.</param>
        /// <param name="password">The password. Must consists of 6 chars or more.</param>
        /// <param name="iterations">The number of iterations to derive the key. Should not be adjusted. The default is secure for the current time.</param>
        /// <returns>The decrypted UTF8 encoded string.</returns>
        public static async Task<string> Decrypt(this string data, string password, int iterations = CryptoProcessor.ITERATIONS_YEAR_2020)
        {
            return await CryptoProcessor.Decrypt(data, password, iterations);
        }

        /// <summary>
        /// Decrypts a given input stream and writes the decrypted data to the provided output stream. A buffer stream
        /// gets used in front of the output stream. This method expects, that both streams are read-to-use e.g. the
        /// input stream is at the desired position and the output stream is writable, etc. This method disposes the
        /// internal crypto streams. Thus, the input and output streams might get disposed as well. Please note, that
        /// this method writes binary data without e.g. base64 encoding.
        ///
        /// When the task finished, the entire decryption of the input stream is done.
        /// </summary>
        /// <param name="inputStream">The desired input stream. The decryption starts at the current position.</param>
        /// <param name="outputStream">The desired output stream. The decrypted data gets written to the current position.</param>
        /// <param name="password">The encryption password.</param>
        /// <param name="iterations">The number of iterations to derive the key. Should not be adjusted. The default is secure for the current time.</param>
        public static async Task Decrypt(this Stream inputStream, Stream outputStream, string password, int iterations = CryptoProcessor.ITERATIONS_YEAR_2020)
        {
            await CryptoProcessor.Decrypt(inputStream, outputStream, password, iterations);
        }
    }
}