/// <summary>
/// Calculates the checksum of a file
/// </summary>
/// <param name="filePath">path to the file to be checked</param>
/// <param name="hashingAlgorithm">The hashing algo to be used. Defaults to SHA256</param>
/// <returns>Byte array representing the checksum of the file</returns>
/// <exception cref="ArgumentException">The hashing algo supplied is not supported by the OS/Language Version</exception>
public static byte[] GetChecksum(string filePath, HashingAlgorithm hashingAlgorithm = HashingAlgorithm.SHA256)
{
using (var hasher = System.Security.Cryptography.HashAlgorithm.Create(hashingAlgorithm.ToString()))
{
if (hasher == null)
{
throw new ArgumentException($"{hashingAlgorithm} not a valid hashing algorithm");
}
using (var stream = System.IO.File.OpenRead(filePath))
{
return(hasher.ComputeHash(stream));
}
}
}
public Task <IHashingService> CreateHashingService(HashingAlgorithm algorithm)
{
switch (algorithm)
{
case HashingAlgorithm.PBKDF2_HMACSHA1_1000:
return(Task.FromResult <IHashingService>(new Pbkdf2HashingService_HMACSHA1_1000()));
case HashingAlgorithm.PBKDF2_HMACSHA256_1000:
return(Task.FromResult <IHashingService>(new Pbkdf2HashingService_HMACSHA256_1000()));
case HashingAlgorithm.PBKDF2_HMACSHA512_1000:
return(Task.FromResult <IHashingService>(new Pbkdf2HashingService_HMACSHA512_1000()));
default: throw new ApplicationException($"Error creating hashing service with algorithm [{algorithm.ToString()}], a hashing service with this algorithm does not exist.");
}
}