scrypt

Documentation

Overview

Package scrypt provides helpful abstractions for an implementation of RFC7914 and implements github.com/go-crypt/crypt interfaces.

This implementation is loaded by crypt.NewDefaultDecoder and crypt.NewDecoderAll.

Index

• Constants
• func Decode(encodedDigest string) (digest algorithm.Digest, err error)
• func DecodeVariant(v Variant) func(encodedDigest string) (digest algorithm.Digest, err error)
• func RegisterDecoder(r algorithm.DecoderRegister) (err error)
• func RegisterDecoderScrypt(r algorithm.DecoderRegister) (err error)
• func RegisterDecoderYescrypt(r algorithm.DecoderRegister) (err error)
• type Digest
  • func (d *Digest) Encode() string
  • func (d *Digest) Match(password string) (match bool)
  • func (d *Digest) MatchAdvanced(password string) (match bool, err error)
  • func (d *Digest) MatchBytes(passwordBytes []byte) (match bool)
  • func (d *Digest) MatchBytesAdvanced(passwordBytes []byte) (match bool, err error)
  • func (d *Digest) String() string
• type Hasher
  • func New(opts ...Opt) (hasher *Hasher, err error)
  • func NewScrypt(opts ...Opt) (hasher *Hasher, err error)
  • func NewYescrypt(opts ...Opt) (hasher *Hasher, err error)
  • func (h *Hasher) Hash(password string) (digest algorithm.Digest, err error)
  • func (h *Hasher) HashWithSalt(password string, salt []byte) (digest algorithm.Digest, err error)
  • func (h *Hasher) MustHash(password string) (digest algorithm.Digest)
  • func (h *Hasher) Validate() (err error)
  • func (h *Hasher) WithOptions(opts ...Opt) (err error)
• type KeyFunc
• type Opt
  • func WithBlockSize(r int) Opt
  • func WithK(k int) Opt
  • func WithKeyLength(k int) Opt
  • func WithLN(ln int) Opt
  • func WithP(p int) Opt
  • func WithParallelism(p int) Opt
  • func WithR(r int) Opt
  • func WithS(s int) Opt
  • func WithSaltLength(s int) Opt
  • func WithVariant(variant Variant) Opt
  • func WithVariantName(identifier string) Opt
• type Variant
  • func NewVariant(identifier string) (variant Variant)
  • func (v Variant) Encode(ln, r, p int, salt, key []byte) (f string)
  • func (v Variant) KeyFunc() KeyFunc
  • func (v Variant) Prefix() (prefix string)
  • func (v Variant) String() (variant string)

Constants

const (
	// EncodingFmt is the format of the encoded digest.
	EncodingFmt = "$%s$ln=%d,r=%d,p=%d$%s$%s"

	// EncodingFmtYescrypt is the format of the encoded digest.
	EncodingFmtYescrypt = "$%s$%s$%s$%s"

	// AlgName is the name for this algorithm.
	AlgName = "scrypt"

	// AlgNameYescrypt is the name for this algorithm's yescrypt variant.
	AlgNameYescrypt = "yescrypt"

	// KeyLengthMin is the minimum key length accepted.
	KeyLengthMin = 1

	// SaltLengthMin is the minimum salt length accepted.
	SaltLengthMin = 8

	// SaltLengthMax is the maximum salt length accepted.
	SaltLengthMax = 1024

	// IterationsMin is the minimum number of iterations accepted.
	IterationsMin = 1

	// IterationsMax is the maximum number of iterations accepted.
	IterationsMax = 58

	// IterationsDefault is the default number of iterations.
	IterationsDefault = 16

	// BlockSizeMin is the minimum block size accepted.
	BlockSizeMin = 1

	// BlockSizeMax is the maximum block size accepted.
	BlockSizeMax = math.MaxInt / 256

	// BlockSizeDefault is the default block size.
	BlockSizeDefault = 8

	// ParallelismMin is the minimum parallelism factor accepted.
	ParallelismMin = 1

	// ParallelismMax is the maximum parallelism factor accepted.
	//
	// Equation is based on the following text from RFC:
	//
	//   The parallelization parameter p
	//   ("parallelizationParameter") is a positive integer less than or equal
	//   to ((2^32-1) * 32) / (128 * r).
	//
	//   When r has a minimum of 1, this makes the equation ((2^32-1) * 32) / 128.
	ParallelismMax = 1073741823

	// ParallelismDefault is the default parallelism factor.
	ParallelismDefault = ParallelismMin
)

const (
	AlgIdentifier = AlgName

	AlgIdentifierYescrypt = "y"
)

const (
	// KeyLengthMax is the maximum key size accepted.
	KeyLengthMax = math.MaxUint32 * 32
)

Functions

func Decode

func Decode(encodedDigest string) (digest algorithm.Digest, err error)

Decode the encoded digest into a algorithm.Digest.

func DecodeVariant

func DecodeVariant(v Variant) func(encodedDigest string) (digest algorithm.Digest, err error)

DecodeVariant the encoded digest into a algorithm.Digest provided it matches the provided scrypt.Variant. If scrypt.VariantNone is used all variants can be decoded.

func RegisterDecoder

func RegisterDecoder(r algorithm.DecoderRegister) (err error)

RegisterDecoder the decoder with the algorithm.DecoderRegister.

func RegisterDecoderScrypt

func RegisterDecoderScrypt(r algorithm.DecoderRegister) (err error)

RegisterDecoderScrypt the scrypt decoder with the algorithm.DecoderRegister.

func RegisterDecoderYescrypt

func RegisterDecoderYescrypt(r algorithm.DecoderRegister) (err error)

RegisterDecoderYescrypt the yescrypt decoder with the algorithm.DecoderRegister.

Types

type Digest

type Digest struct {
	// contains filtered or unexported fields
}

Digest is a scrypt.Digest which handles scrypt hashes.

func (*Digest) Encode

func (d *Digest) Encode() string

Encode returns the encoded form of this scrypt.Digest.

func (*Digest) Match

func (d *Digest) Match(password string) (match bool)

Match returns true if the string password matches the current scrypt.Digest.

func (*Digest) MatchAdvanced

func (d *Digest) MatchAdvanced(password string) (match bool, err error)

MatchAdvanced is the same as Match except if there is an error it returns that as well.

func (*Digest) MatchBytes

func (d *Digest) MatchBytes(passwordBytes []byte) (match bool)

MatchBytes returns true if the []byte passwordBytes matches the current scrypt.Digest.

func (*Digest) MatchBytesAdvanced

func (d *Digest) MatchBytesAdvanced(passwordBytes []byte) (match bool, err error)

MatchBytesAdvanced is the same as MatchBytes except if there is an error it returns that as well.

func (*Digest) String

func (d *Digest) String() string

String returns the storable format of the scrypt.Digest encoded hash.

type Hasher

type Hasher struct {
	// contains filtered or unexported fields
}

Hasher is a crypt.Hash for scrypt which can be initialized via New using a functional options pattern.

func New

func New(opts ...Opt) (hasher *Hasher, err error)

New returns a new scrypt.Hasher with the provided functional options applied.

func NewScrypt

func NewScrypt(opts ...Opt) (hasher *Hasher, err error)

func NewYescrypt

func NewYescrypt(opts ...Opt) (hasher *Hasher, err error)

func (*Hasher) Hash

func (h *Hasher) Hash(password string) (digest algorithm.Digest, err error)

Hash performs the hashing operation and returns either a Digest or an error.

func (*Hasher) HashWithSalt

func (h *Hasher) HashWithSalt(password string, salt []byte) (digest algorithm.Digest, err error)

HashWithSalt overloads the Hash method allowing the user to provide a salt. It's recommended instead to configure the salt size and let this be a random value generated using crypto/rand.

func (*Hasher) MustHash

func (h *Hasher) MustHash(password string) (digest algorithm.Digest)

MustHash overloads the Hash method and panics if the error is not nil. It's recommended if you use this option to utilize the Validate method first or handle the panic appropriately.

func (*Hasher) Validate

func (h *Hasher) Validate() (err error)

Validate checks the settings/parameters for this Hash and returns an error.

func (*Hasher) WithOptions

func (h *Hasher) WithOptions(opts ...Opt) (err error)

WithOptions defines the options for this scrypt.Hasher.

type KeyFunc

type KeyFunc func(password []byte, salt []byte, N int, r int, p int, keyLen int) (key []byte, err error)

KeyFunc represents the KeyFunc used by scrypt implementations.

type Opt

type Opt func(h *Hasher) (err error)

Opt describes the functional option pattern for the scrypt.Hasher.

func WithBlockSize

func WithBlockSize(r int) Opt

WithBlockSize is an alias for WithR.

func WithK

func WithK(k int) Opt

WithK adjusts the key length of the resulting scrypt.Digest. Minimum is 1, Maximum is 137438953440. Default is 32.

func WithKeyLength

func WithKeyLength(k int) Opt

WithKeyLength is an alias for WithK.

func WithLN

func WithLN(ln int) Opt

WithLN sets the ln parameter (logN) of the resulting scrypt.Digest. Minimum is 1, Maximum is 58. Default is 16.

func WithP

func WithP(p int) Opt

WithP sets the p parameter (parallelism factor) of the resulting scrypt.Digest. Minimum is 1, Maximum is 1073741823. Default is 1.

func WithParallelism

func WithParallelism(p int) Opt

WithParallelism is an alias for WithP.

func WithR

func WithR(r int) Opt

WithR sets the r parameter (block size) of the resulting scrypt.Digest. Minimum is 1, Maximum is math.MaxInt / 256. Default is 8.

func WithS

func WithS(s int) Opt

WithS adjusts the salt length of the resulting scrypt.Digest. Minimum is 8, Maximum is 1024. Default is 16.

func WithSaltLength

func WithSaltLength(s int) Opt

WithSaltLength is an alias for WithS.

func WithVariant

func WithVariant(variant Variant) Opt

WithVariant configures the scrypt.Variant of the resulting scrypt.Digest. Default is scrypt.VariantScrypt.

func WithVariantName

func WithVariantName(identifier string) Opt

WithVariantName uses the variant name or identifier to configure the scrypt.Variant of the resulting scrypt.Digest. Default is scrypt.VariantScrypt.

type Variant

type Variant int

Variant is a variant of the scrypt.Digest.

const (
	// VariantNone is the default variant of Scrypt.
	VariantNone Variant = iota

	VariantScrypt

	VariantYescrypt
)

func NewVariant

func NewVariant(identifier string) (variant Variant)

NewVariant converts an identifier string to a scrypt.Variant.

func (Variant) Encode

func (v Variant) Encode(ln, r, p int, salt, key []byte) (f string)

Encode formats the variant encoded bcrypt.Digest.

func (Variant) KeyFunc

func (v Variant) KeyFunc() KeyFunc

KeyFunc returns the internal HMAC algorithm.HashFunc.

func (Variant) Prefix

func (v Variant) Prefix() (prefix string)

Prefix returns the scrypt.Variant prefix identifier.

func (Variant) String

func (v Variant) String() (variant string)

String implements the fmt.Stringer returning a string representation of the scrypt.Variant.