Program.cs

using System;
using System.Linq;
using System.Security.Cryptography;
using Microsoft.AspNetCore.Cryptography.KeyDerivation;

namespace IdentityV3PasswordHasher
{
    class Program
    {
        static void Main(string[] args)
        {
            if (args.Length == 0)
            {
                PrintUsage();
                return;
            }

            switch (args[0])
            {
                case "hash":
                    if (args.Length != 2) {
                        PrintUsage();
                        break;
                    }
                    Console.WriteLine(PasswordHasher.GenerateIdentityV3Hash(args[1]));
                    break;
                case "verify":                    
                    if (args.Length != 3){
                        PrintUsage();
                        break;                        
                    }
                    var password = args[1];
                    var identityV3Hash = args[2];
                    Console.WriteLine(PasswordHasher.VerifyIdentityV3Hash(password, identityV3Hash) ? "Password is correct" : "Wrong password");
                    break;
                default:
                    PrintUsage();
                    break;

            }
        }

        private static void PrintUsage()
        {
            Console.WriteLine("Usage: " + Environment.NewLine);
            Console.WriteLine("Generate ASP.NET Identity V3 Hash: hash [Password]");
            Console.WriteLine("Validate ASP.NET Identity V3 Password/Hash: verify [Password] [IdentityV3Hash]");
        }


    }
}