Class CryptoPasswordHashScrypt

Namespace

LibSodium

Assembly

LibSodium.Net.dll

Provides password hashing and key derivation using the Scrypt algorithm.

public static class CryptoPasswordHashScrypt

Inheritance

object

CryptoPasswordHashScrypt

Inherited Members

object.Equals(object)

object.Equals(object, object)

object.GetHashCode()

object.GetType()

object.MemberwiseClone()

object.ReferenceEquals(object, object)

object.ToString()

Remarks

Based on libsodium's crypto_pwhash_scryptsalsa208sha256 API: https://doc.libsodium.org/advanced/scrypt

Fields

EncodedLen

Maximum length of the encoded hash string (includes null terminator) (102).

public const int EncodedLen = 102

Field Value

int

InteractiveIterations

Recommended iterations for login or general use (2^19 = 421Mi).

public const int InteractiveIterations = 524288

Field Value

int

InteractiveMemoryLen

Recommended memory usage for interactive scenarios (2^24 = 16 MiB).

public const int InteractiveMemoryLen = 16777216

Field Value

int

MinIterations

Minimum recommended iterations for dual-phase scenarios (2^10 = 1Ki).

public const int MinIterations = 1024

Field Value

int

MinKeyLen

Minimum allowed length in bytes for the derived key (16).

public const int MinKeyLen = 16

Field Value

int

MinMemoryLen

Minimum recommended memory usage (2^15 = 32 KiB).

public const int MinMemoryLen = 32768

Field Value

int

MinPasswordLen

Minimum allowed password length in bytes (0).

public const int MinPasswordLen = 0

Field Value

int

ModerateIterations

Recommended iterations for moderate-strength secrets (2^22 = 4Gi).

public const int ModerateIterations = 4194304

Field Value

int

ModerateMemoryLen

Recommended memory usage for moderate-strength secrets (2^27 = 128 MiB).

public const int ModerateMemoryLen = 134217728

Field Value

int

Prefix

Prefix for the encoded hash string (e.g. "\(7\)").

public const string Prefix = "$7$"

Field Value

string

SaltLen

Length of the salt in bytes (32).

public const int SaltLen = 32

Field Value

int

SensitiveIterations

Recommended iterations for high-value secrets (2^25 = 32Gi).

public const int SensitiveIterations = 33554432

Field Value

int

SensitiveMemoryLen

Recommended memory usage for high-value secrets (2^30 = 1 GiB).

public const int SensitiveMemoryLen = 1073741824

Field Value

int

Methods

DeriveKey(SecureMemory<byte>, SecureMemory<byte>, ReadOnlySpan<byte>, int, int)

Derives a secret key from a password and salt using scrypt.

public static void DeriveKey(SecureMemory<byte> key, SecureMemory<byte> password, ReadOnlySpan<byte> salt, int iterations = 524288, int requiredMemoryLen = 16777216)

Parameters

key SecureMemory<byte>

Buffer to receive the derived key (recommended: 32 bytes).

password SecureMemory<byte>

The password to hash.

salt ReadOnlySpan<byte>

The salt (must be 32 bytes).

iterations int

Computation cost (default: INTERACTIVE).

requiredMemoryLen int

Memory usage limit in bytes (default: INTERACTIVE).

Exceptions

ArgumentException

If arguments are invalid.

LibSodiumException

If hashing fails.

DeriveKey(SecureMemory<byte>, string, ReadOnlySpan<byte>, int, int)

Derives a secret key from a password string and salt using scrypt.

public static void DeriveKey(SecureMemory<byte> key, string password, ReadOnlySpan<byte> salt, int iterations = 524288, int requiredMemoryLen = 16777216)

Parameters

key SecureMemory<byte>

Buffer to receive the derived key (recommended: 32 bytes).

password string

The password string to hash.

salt ReadOnlySpan<byte>

The salt (must be 32 bytes).

iterations int

Computation cost (default: INTERACTIVE).

requiredMemoryLen int

Memory usage limit in bytes (default: INTERACTIVE).

Exceptions

ArgumentNullException

If the password is null.

LibSodiumException

If hashing fails.

DeriveKey(Span<byte>, ReadOnlySpan<byte>, ReadOnlySpan<byte>, int, int)

Derives a secret key from a password and salt using scrypt.

public static void DeriveKey(Span<byte> key, ReadOnlySpan<byte> password, ReadOnlySpan<byte> salt, int iterations = 524288, int requiredMemoryLen = 16777216)

Parameters

key Span<byte>

Buffer to receive the derived key (recommended: 32 bytes).

password ReadOnlySpan<byte>

The password to hash.

salt ReadOnlySpan<byte>

The salt (must be 32 bytes).

iterations int

Computation cost (default: INTERACTIVE).

requiredMemoryLen int

Memory usage limit in bytes (default: INTERACTIVE).

Exceptions

ArgumentException

If arguments are invalid.

LibSodiumException

If hashing fails.

DeriveKey(Span<byte>, string, ReadOnlySpan<byte>, int, int)

Derives a secret key from a password string and salt using scrypt.

public static void DeriveKey(Span<byte> key, string password, ReadOnlySpan<byte> salt, int iterations = 524288, int requiredMemoryLen = 16777216)

Parameters

key Span<byte>

Buffer to receive the derived key (recommended: 32 bytes).

password string

The password string to hash.

salt ReadOnlySpan<byte>

The salt (must be 32 bytes).

iterations int

Computation cost (default: INTERACTIVE).

requiredMemoryLen int

Memory usage limit in bytes (default: INTERACTIVE).

Exceptions

ArgumentNullException

If the password is null.

LibSodiumException

If hashing fails.

HashPassword(SecureMemory<byte>, int, int)

Hashes a password into a human-readable string (including algorithm and parameters).

public static string HashPassword(SecureMemory<byte> password, int iterations = 524288, int requiredMemoryLen = 16777216)

Parameters

password SecureMemory<byte>

The password to hash (in UTF-8).

iterations int

Computation cost (default: INTERACTIVE).

requiredMemoryLen int

Memory usage limit in bytes (default: INTERACTIVE).

Returns

string

A string containing only ASCII characters, including the algorithm identifier, salt, and parameters.

Exceptions

ArgumentOutOfRangeException

If password is too short or parameters are invalid.

LibSodiumException

If hashing fails.

HashPassword(ReadOnlySpan<byte>, int, int)

Hashes a password into a human-readable string (including algorithm and parameters).

public static string HashPassword(ReadOnlySpan<byte> password, int iterations = 524288, int requiredMemoryLen = 16777216)

Parameters

password ReadOnlySpan<byte>

The password to hash (in UTF-8).

iterations int

Computation cost (default: INTERACTIVE).

requiredMemoryLen int

Memory usage limit in bytes (default: INTERACTIVE).

Returns

string

A string containing only ASCII characters, including the algorithm identifier, salt, and parameters.

Exceptions

ArgumentOutOfRangeException

If password is too short or parameters are invalid.

LibSodiumException

If hashing fails.

HashPassword(string, int, int)

Hashes a password string into a human-readable string (including algorithm and parameters).

public static string HashPassword(string password, int iterations = 524288, int requiredMemoryLen = 16777216)

Parameters

password string

The password to hash (as string).

iterations int

Computation cost (default: INTERACTIVE).

requiredMemoryLen int

Memory usage limit in bytes (default: INTERACTIVE).

Returns

string

A string containing only ASCII characters, including the algorithm identifier, salt, and parameters.

Exceptions

ArgumentNullException

If the password is null.

ArgumentOutOfRangeException

If parameters are invalid.

LibSodiumException

If hashing fails.

VerifyPassword(string, SecureMemory<byte>)

Verifies a password against a previously hashed string.

public static bool VerifyPassword(string hashedPassword, SecureMemory<byte> password)

Parameters

hashedPassword string

The encoded password hash string (must be ASCII and null-terminated).

password SecureMemory<byte>

The password to verify.

Returns

bool

true if the password is valid; otherwise, false.

Exceptions

ArgumentNullException

If hashedPassword is null.

ArgumentException

If hashedPassword is too long.

VerifyPassword(string, ReadOnlySpan<byte>)

Verifies a password against a previously hashed string.

public static bool VerifyPassword(string hashedPassword, ReadOnlySpan<byte> password)

Parameters

hashedPassword string

The encoded password hash string (must be ASCII and null-terminated).

password ReadOnlySpan<byte>

The password to verify.

Returns

bool

true if the password is valid; otherwise, false.

Exceptions

ArgumentNullException

If hashedPassword is null.

ArgumentException

If hashedPassword is too long.

VerifyPassword(string, string)

Verifies a password string against a previously hashed string.

public static bool VerifyPassword(string hashedPassword, string password)

Parameters

hashedPassword string

The encoded password hash string (must be ASCII and null-terminated).

password string

The password to verify (as string).

Returns

bool

true if the password is valid; otherwise, false.

Exceptions

ArgumentNullException

If password is null.