ModernUO/Projects/Argon2/Argon2PasswordHasher.cs
2020-05-01 22:42:39 -07:00

388 lines
18 KiB
C#

using System;
using System.Runtime.InteropServices;
using System.Security.Cryptography;
using System.Text;
// using System.Text.RegularExpressions;
namespace Server.Accounting.Security
{
/// <summary>
/// PasswordHasher is a class for creating Argon2 hashes and verifying them. This is a wrapper around
/// Daniel Dinu and Dmitry Khovratovich's Argon2 library.
/// </summary>
public class Argon2PasswordHasher
{
private static readonly RNGCryptoServiceProvider Rng = new RNGCryptoServiceProvider();
// private static readonly Regex HashRegex = new Regex(@"^\$argon2([di])\$v=(\d+)$m=(\d+),t=(\d+),p=(\d+)\$([A-Za-z0-9+/=]+)\$([A-Za-z0-9+/=]*)$", RegexOptions.Compiled);
/// <summary>
/// How many iterations of the Argon2 hash to perform
/// </summary>
public uint TimeCost { get; set; }
/// <summary>
/// How much memory to use while hashing in kibibytes (KiB)
/// </summary>
public uint MemoryCost { get; set; }
/// <summary>
/// How many threads to use while hashing
/// </summary>
public uint Parallelism { get; set; }
/// <summary>
/// The type of Argon2 hashing algorithm to use
/// Argon2d - The memory access is dependent upon the hash value (vulnerable to side-channel attacks)
/// Argon2i - The memory access is independent upon the hash value (safe from side-channel atacks)
/// </summary>
public Argon2Type ArgonType { get; set; }
/// <summary>
/// Length of the generated raw hash in bytes
/// </summary>
public uint HashLength { get; set; }
/// <summary>
/// How strings should be decoded when passed to the Hash method.
/// The default is Encoding.UTF8.
/// </summary>
public Encoding StringEncoding { get; set; }
/// <summary>
/// Initialize the Argon2 PasswordHasher with default performance and algorithm settings based upon the environment the hashing will be used in.
/// You should perform your own profiling to determine what the parameters should be for your specific usage; however, this attempts to provide
/// some reasonable defaults.
/// </summary>
public Argon2PasswordHasher()
{
TimeCost = 3;
MemoryCost = 8192;
Parallelism = 1;
ArgonType = Argon2Type.Argon2i;
HashLength = 32;
StringEncoding = Encoding.UTF8;
}
/// <summary>
/// Initialize the Argon2 PasswordHasher with the performance and algorithm settings to use while hashing
/// <param name="timeCost">How many iterations of the Argon2 hash to perform (default: 3, must be at least 1)</param>
/// <param name="memoryCost">How much memory to use while hashing in kibibytes (KiB) (default: 8192 KiB [8 MiB], must be at least 8 KiB)</param>
/// <param name="parallelism">How many threads to use while hashing (default: 1, must be at least 1)</param>
/// <param name="argonType">The type of Argon2 hashing algorithm to use (Independent [default] or Dependent)</param>
/// <param name="hashLength">The length of the resulting hash in bytes (default: 32)</param>
/// </summary>
public Argon2PasswordHasher(uint timeCost = 3, uint memoryCost = 8192, uint parallelism = 1, Argon2Type argonType = Argon2Type.Argon2i, uint hashLength = 32)
{
TimeCost = timeCost;
MemoryCost = memoryCost;
Parallelism = parallelism;
ArgonType = argonType;
HashLength = hashLength;
StringEncoding = Encoding.UTF8;
}
/// <summary>
/// Hash the password using Argon2 with a cryptographically-secure, random, 16-byte salt.
/// This is the only overload of the Hash method that the typical user will need to use for password storage. The other overloads are provided for interoperability purposes.
/// Do not compare two Argon2 hashes directly. Instead, use the Verify or VerifyAndUpdate methods.
/// <param name="password">A string representing the password to be hashed. The password is first decoded into bytes using StringEncoding (default: Encoding.UTF8)</param>
/// <returns>A formatted string representing the hashed password, encoded with the parameters used to perform the hash</returns>
/// </summary>
public string Hash(string password)
{
CheckNull("Hash", "password", password);
return Hash(StringEncoding.GetBytes(password));
}
/// <summary>
/// Hash the raw password bytes using Argon2 with a cryptographically-secure, random, 16-byte salt.
/// Do not compare two Argon2 hashes directly. Instead, use the Verify or VerifyAndUpdate methods.
/// <param name="password">The raw bytes of the password to be hashed</param>
/// <returns>A formatted string representing the hashed password, encoded with the parameters used to perform the hash</returns>
/// </summary>
public string Hash(byte[] password)
{
CheckNull("Hash", "password", password);
return Hash(password, GenerateSalt());
}
/// <summary>
/// Hash the password using Argon2 with the specified salt.
/// Unless you need to specify your own salt for interoperability purposes, prefer the Hash(string password) overload instead.
/// Do not compare two Argon2 hashes directly. Instead, use the Verify or VerifyAndUpdate methods.
/// <param name="password">A string representing the password to be hashed. The password is first decoded into bytes using StringEncoding (default: Encoding.UTF8)</param>
/// <param name="salt">A string representing the salt to be used for the hash. The salt must be at least 8 bytes. The salt is first decoded into bytes using StringEncoding (default: Encoding.UTF8)</param>
/// <returns>A formatted string representing the hashed password, encoded with the parameters used to perform the hash</returns>
/// </summary>
public string Hash(string password, string salt)
{
CheckNull("Hash", "password", password, "salt", salt);
return Hash(StringEncoding.GetBytes(password), StringEncoding.GetBytes(salt));
}
/// <summary>
/// Hash the raw password bytes using Argon2 with the specified salt bytes.
/// Unless you need to specify your own salt for interoperability purposes, prefer the Hash(byte[] password) overload instead.
/// Do not compare two Argon2 hashes directly. Instead, use the Verify or VerifyAndUpdate methods.
/// <param name="password">The raw bytes of the password to be hashed</param>
/// <param name="salt">The raw salt bytes to be used for the hash. The salt must be at least 8 bytes.</param>
/// <returns>A formatted string representing the hashed password, encoded with the parameters used to perform the hash</returns>
/// </summary>
public string Hash(byte[] password, byte[] salt)
{
CheckNull("Hash", "password", password, "salt", salt);
byte[] hash = new byte[HashLength];
byte[] encoded = new byte[39 + ((HashLength + salt.Length) * 4 + 3) / 3];
var result = Argon2.Library.Hash(
TimeCost,
MemoryCost,
Parallelism,
password,
salt,
hash,
encoded,
(int)ArgonType,
0x13
);
if (result != Argon2Error.OK)
throw new Argon2Exception("hashing", result);
var firstNonNull = encoded.Length - 2;
while (encoded[firstNonNull] == 0)
firstNonNull--;
return Encoding.ASCII.GetString(encoded, 0, firstNonNull + 1);
}
/// <summary>
/// Hash the password using Argon2 with the specified salt. The HashRaw methods may be used for password-based key derivation.
/// Unless you're using HashRaw for key deriviation or for interoperability purposes, the Hash methods should be used in favor of the HashRaw methods.
/// <param name="password">A string representing the password to be hashed. The password is first decoded into bytes using StringEncoding (default: Encoding.UTF8)</param>
/// <param name="salt">A string representing the salt to be used for the hash. The salt must be at least 8 bytes. The salt is first decoded into bytes using StringEncoding (default: Encoding.UTF8)</param>
/// <returns>A byte array containing only the resulting hash</returns>
/// </summary>
public byte[] HashRaw(string password, string salt)
{
CheckNull("HashRaw", "password", password, "salt", salt);
return HashRaw(StringEncoding.GetBytes(password), StringEncoding.GetBytes(salt));
}
/// <summary>
/// Hash the password using Argon2 with the specified salt. The HashRaw methods may be used for password-based key derivation.
/// Unless you're using HashRaw for key deriviation or for interoperability purposes, the Hash methods should be used in favor of the HashRaw methods.
/// <param name="password">The raw bytes of the password to be hashed</param>
/// <param name="salt">The raw salt bytes to be used for the hash. The salt must be at least 8 bytes.</param>
/// <returns>A byte array containing only the resulting hash</returns>
/// </summary>
public byte[] HashRaw(byte[] password, byte[] salt)
{
byte[] hash = new byte[(int)HashLength];
var result = Argon2.Library.Hash(
TimeCost,
MemoryCost,
Parallelism,
password,
salt,
hash,
null,
(int)ArgonType,
0x13
);
if (result != Argon2Error.OK)
throw new Argon2Exception("raw hashing", result);
return hash;
}
/// <summary>
/// Hashes the password and verifies that the password results in the specified hash.
/// The ArgonType must of this PasswordHasher object must match what was used to generate expectedHash.
/// The other parameters (timeCost, etc.) do not need to match and the parameters embedded in the expectedHash will be used.
/// <param name="expectedHash">Hashing the password should result in this hash</param>
/// <param name="password">The password to hash and compare its result to expectedHash. The password is first decoded into bytes using StringEncoding (default: Encoding.UTF8)</param>
/// <returns>Whether the password results in the expectedHash when hashed</returns>
/// </summary>
public bool Verify(string expectedHash, string password)
{
CheckNull("Verify", "expectedHash", expectedHash, "password", password);
return Verify(expectedHash, StringEncoding.GetBytes(password));
}
/// <summary>
/// Hashes the raw password bytes and verifies that the password results in the specified hash.
/// The ArgonType must of this PasswordHasher object must match what was used to generate expectedHash.
/// The other parameters (timeCost, etc.) do not need to match and the parameters embedded in the expectedHash will be used.
/// <param name="expectedHash">Hashing the password should result in this hash</param>
/// <param name="password">The raw password bytes to hash and compare its result to expectedHash</param>
/// <returns>Whether the password results in the expectedHash when hashed</returns>
/// </summary>
public bool Verify(string expectedHash, byte[] password)
{
CheckNull("Verify", "expectedHash", expectedHash, "password", password);
var result = Argon2.Library.Verify(StringEncoding.GetBytes(expectedHash), password, password.Length, (int)ArgonType);
if (result == Argon2Error.OK || result == Argon2Error.VERIFY_MISMATCH || result == Argon2Error.DECODING_FAIL)
return result == Argon2Error.OK;
throw new Argon2Exception("verifying", result);
}
/// <summary>
/// Hashes the password and verifies that the password results in the specified hash. (See Verify method)
/// If the password verification is successful, this method checks to see if the memory cost, time cost, and parallelism
/// match the parameters the PasswordHasher object was constructed with. If they do not much, then the password is rehashed
/// using the new parameters and the result is outputted via the newFormattedHash parameter.
/// <param name="expectedHash">Hashing the password should result in this hash</param>
/// <param name="password">The password to hash and compare its result to expectedHash. The password is first decoded into bytes using StringEncoding (default: Encoding.UTF8)</param>
/// <param name="isUpdated">Whether the cost parameters of expectedHash differ from the PasswordHasher object and if the password was rehashed using th new parameters. This is always false if the password was incorrect.</param>
/// <param name="newFormattedHash">If isUpdated is true, then newFormattedHash is the password hashed with the new cost parameters. If isUpdated is false, then newFormattedHash is expectedHash.</param>
/// <returns>Whether the password results in the expectedHash when hashed</returns>
/// </summary>
public bool VerifyAndUpdate(string expectedHash, string password, out bool isUpdated, out string newFormattedHash)
{
CheckNull("VerifyAndUpdate", "expectedHash", expectedHash, "password", password);
return VerifyAndUpdate(expectedHash, StringEncoding.GetBytes(password), out isUpdated, out newFormattedHash);
}
/// <summary>
/// Hashes the password and verifies that the password results in the specified hash. (See Verify method)
/// If the password verification is successful, this method checks to see if the memory cost, time cost, and parallelism
/// match the parameters the PasswordHasher object was constructed with. If they do not much, then the password is rehashed
/// using the new parameters and the result is outputted via the newFormattedHash parameter.
/// <param name="expectedHash">Hashing the password should result in this hash</param>
/// <param name="password">The raw password bytes to hash and compare its result to expectedHash</param>
/// <param name="isUpdated">Whether the cost parameters of expectedHash differ from the PasswordHasher object and if the password was rehashed using th new parameters. This is always false if the password was incorrect.</param>
/// <param name="newFormattedHash">If isUpdated is true, then newFormattedHash is the password hashed with the new cost parameters. If isUpdated is false, then newFormattedHash is expectedHash.</param>
/// <returns>Whether the password results in the expectedHash when hashed</returns>
/// </summary>
public bool VerifyAndUpdate(string expectedHash, byte[] password, out bool isUpdated, out string newFormattedHash)
{
CheckNull("VerifyAndUpdate", "expectedHash", expectedHash, "password", password);
if (Verify(expectedHash, password))
{
var hashMetadata = ExtractMetadata(expectedHash);
if (hashMetadata.MemoryCost != MemoryCost || hashMetadata.TimeCost != TimeCost || hashMetadata.Parallelism != Parallelism)
{
isUpdated = true;
byte[] salt = hashMetadata.Salt;
newFormattedHash = Hash(password, salt);
}
else
{
isUpdated = false;
newFormattedHash = expectedHash;
}
return true;
}
isUpdated = false;
newFormattedHash = expectedHash;
return false;
}
/// <summary>
/// Generate salt using a Cryptographically-Secure Pseudo-Random Number Generator
/// <param name="byteLength">The number of bytes of salt to generate (default: 16)</param>
/// <returns>A array of randomly-generated bytes</returns>
/// </summary>
public static byte[] GenerateSalt(uint byteLength = 16)
{
var salt = new byte[byteLength];
Rng.GetBytes(salt);
return salt;
}
/// <summary>
/// Extracts the memory cost, time cost, etc. used to generate the Argon2 hash.
/// <param name="formattedHash">An encoded Argon2 hash created by the Hash method</param>
/// <returns>The hash metadata or null if the formattedHash was not a valid encoded Argon2 hash</returns>
/// </summary>
public static HashMetadata ExtractMetadata(string formattedHash)
{
CheckNull("ExtractMetadata", "formattedHash", formattedHash);
var context = new Argon2Context
{
Out = Marshal.AllocHGlobal(formattedHash.Length), // ensure the space to hold the hash is long enough
OutLen = (uint)formattedHash.Length,
Pwd = Marshal.AllocHGlobal(1),
PwdLen = 1,
Salt = Marshal.AllocHGlobal(formattedHash.Length), // ensure the space to hold the salt is long enough
SaltLen = (uint)formattedHash.Length,
Secret = Marshal.AllocHGlobal(1),
SecretLen = 1,
AssocData = Marshal.AllocHGlobal(1),
AssocDataLen = 1,
TimeCost = 0,
MemoryCost = 0,
Lanes = 0,
Threads = 0
};
try
{
var type = formattedHash.StartsWith("$argon2i") ? Argon2Type.Argon2i : Argon2Type.Argon2d;
var result = Argon2.Library.Decode(context, $"{formattedHash}\0", (int)type);
if (result != Argon2Error.OK)
return null;
var salt = new byte[context.SaltLen];
var hash = new byte[context.OutLen];
Marshal.Copy(context.Salt, salt, 0, salt.Length);
Marshal.Copy(context.Out, hash, 0, hash.Length);
return new HashMetadata
{
ArgonType = type,
MemoryCost = context.MemoryCost,
TimeCost = context.TimeCost,
Parallelism = context.Threads,
Salt = salt,
Hash = hash
};
}
finally
{
Marshal.FreeHGlobal(context.Out);
Marshal.FreeHGlobal(context.Pwd);
Marshal.FreeHGlobal(context.Salt);
Marshal.FreeHGlobal(context.Secret);
Marshal.FreeHGlobal(context.AssocData);
}
}
private static void CheckNull(string methodName, params object[] arguments)
{
for (var i = 0; i < arguments.Length; i += 2)
if (arguments[i + 1] == null)
throw new ArgumentNullException(arguments[i].ToString(), string.Format("Argument {0} to method PasswordHasher.{1} is null", arguments[i], methodName));
}
}
}