crypto

package
v1.9.7-0...-74d8852 Latest Latest
Warning

This package is not in the latest version of its module.

 Go to latest Published: Feb 25, 2025 License: LGPL-3.0 Imports: 10 Imported by: 0

README

Context

This is ported from https://github.com/shutter-network/shutter/tree/main/shlib/shcrypto to avoid introducing a go-ethereum transitive dependency in Erigon.

In the long term, we can work with the shutter team to remove their dependency on go-ethereum for their shcrypto package (doable). When that is done we will be able to simply use their library directly.

Documentation

Index

Constants

View Source 
const BlockSize = 32

BlockSize is the size in bytes of the blocks into which a message is split up before encryption.

View Source 
const HashToG1DST = "SHUTTER_V01_BLS12381G1_XMD:SHA-256_SSWU_RO_"
View Source 
const VersionIdentifier byte = 0x03

Variables

View Source 
var (
	ErrInputTooLong             = errors.New("input too long")
	ErrInvalidEonSecretKeyShare = errors.New("invalid eon secret key share")
	ErrVersionMismatch          = func(version_got byte) error {
		return fmt.Errorf("version mismatch. want %d got %d", VersionIdentifier, version_got)
	}
)

Functions

func DegreeFromThreshold 

func DegreeFromThreshold(threshold uint64) uint64

DegreeFromThreshold returns the degree polynomials should have for the given threshold.

func Hash1 

func Hash1(b []byte) *blst.P1Affine

func Hash3 

func Hash3(b []byte) *big.Int

func IdentifyVersion 

func IdentifyVersion(d []byte) byte

IdentifyVersion reads the version identifier byte from the given (marshaled) EncryptedMessage.

func KeyperX 

func KeyperX(keyperIndex int) *big.Int

KeyperX computes the x value assigned to the keyper identified by its index.

func Uint64toBytes 

func Uint64toBytes(i uint64) ([]byte, int)

func UnpadMessage 

func UnpadMessage(blocks []Block) ([]byte, error)

UnpadMessage returns the message provided in padded form as a sequence of blocks.

func ValidEval 

func ValidEval(v *big.Int) bool

ValidEval checks if the given value is a valid polynomial evaluation, i.e., if it is in Z_q.

func VerifyEpochSecretKey 

func VerifyEpochSecretKey(epochSecretKey *EpochSecretKey, eonPublicKey *EonPublicKey, epochIDBytes []byte) (bool, error)

VerifyEpochSecretKey checks that an epoch secret key is the correct key for an epoch given the eon public key.

func VerifyEpochSecretKeyDeterministic 

func VerifyEpochSecretKeyDeterministic(epochSecretKey *EpochSecretKey, eonPublicKey *EonPublicKey, epochIDBytes []byte, sigma Block, message []byte) (bool, error)

VerifyEpochSecretKeyDeterministic checks that an epoch secret key is the correct key for an epoch given the eon public key and random inputs for sigma and message.

func VerifyEpochSecretKeyShare 

func VerifyEpochSecretKeyShare(epochSecretKeyShare *EpochSecretKeyShare, eonPublicKeyShare *EonPublicKeyShare, epochID *EpochID) bool

VerifyEpochSecretKeyShare checks that an epoch sk share published by a keyper is correct.

func VerifyPolyEval 

func VerifyPolyEval(keyperIndex int, polyEval *big.Int, gammas *Gammas, threshold uint64) bool

VerifyPolyEval checks that the evaluation of a polynomial is consistent with the public gammas.

Types

type Block 

type Block [BlockSize]byte

Block represents a block of data.

func DecryptBlocks 

func DecryptBlocks(encryptedBlocks []Block, sigma Block) []Block

func Hash2 

func Hash2(gt *blst.Fp12) Block

func Hash4 

func Hash4(b []byte) Block

func PadMessage 

func PadMessage(m []byte) []Block

PadMessage pads a message and returns it as a sequence of blocks. Implements PKCS #7 according to https://www.ietf.org/rfc/rfc2315.txt

func RandomSigma 

func RandomSigma(r io.Reader) (Block, error)

RandomSigma returns a random value to be used during encryption.

func XORBlocks 

func XORBlocks(b1 Block, b2 Block) Block

XORBlocks xors the two blocks and returns the result.

func (Block) MarshalText 

func (block Block) MarshalText() ([]byte, error)

MarshalText serializes the block to hex.

func (*Block) UnmarshalText 

func (block *Block) UnmarshalText(b []byte) error

UnmarshalText deserializes the block from hex.

type EncryptedMessage 

type EncryptedMessage struct {
	C1 *blst.P2Affine
	C2 Block
	C3 []Block
}

EncryptedMessage represents the full output of the encryption procedure.

func Encrypt 

func Encrypt(message []byte, eonPublicKey *EonPublicKey, epochID *EpochID, sigma Block) *EncryptedMessage

Encrypt encrypts a message for the epoch given by its id. It uses the eon public key and randomness provided in sigma.

func (*EncryptedMessage) Decrypt 

func (m *EncryptedMessage) Decrypt(epochSecretKey *EpochSecretKey) ([]byte, error)

Decrypt decrypts the given message using the given epoch secret key.

func (*EncryptedMessage) Marshal 

func (m *EncryptedMessage) Marshal() []byte

Marshal serializes the EncryptedMessage object. It panics, if C1 is nil.

func (EncryptedMessage) MarshalText 

func (m EncryptedMessage) MarshalText() ([]byte, error)

MarshalText serializes the encrypted message to hex.

func (*EncryptedMessage) Sigma 

func (m *EncryptedMessage) Sigma(epochSecretKey *EpochSecretKey) Block

Sigma computes the sigma value of the encrypted message given the epoch secret key.

func (*EncryptedMessage) Unmarshal 

func (m *EncryptedMessage) Unmarshal(d []byte) error

Unmarshal deserializes an EncryptedMessage from the given byte slice.

func (*EncryptedMessage) UnmarshalText 

func (m *EncryptedMessage) UnmarshalText(b []byte) error

UnmarshalText deserializes the encrypted message from hex.

type EonPublicKey 

type EonPublicKey blst.P2Affine

EonPublicKey represents the combined eon public key.

func ComputeEonPublicKey 

func ComputeEonPublicKey(gammas []*Gammas) *EonPublicKey

ComputeEonPublicKey computes the combined eon public key from the set of eon public key shares.

func (*EonPublicKey) Equal 

func (eonPublicKey *EonPublicKey) Equal(pk2 *EonPublicKey) bool

func (*EonPublicKey) GobDecode 

func (eonPublicKey *EonPublicKey) GobDecode(data []byte) error

func (*EonPublicKey) GobEncode 

func (eonPublicKey *EonPublicKey) GobEncode() ([]byte, error)

func (*EonPublicKey) Marshal 

func (eonPublicKey *EonPublicKey) Marshal() []byte

Marshal serializes the eon public key.

func (EonPublicKey) MarshalText 

func (eonPublicKey EonPublicKey) MarshalText() ([]byte, error)

MarshalText serializes the eon public key to hex.

func (*EonPublicKey) Unmarshal 

func (eonPublicKey *EonPublicKey) Unmarshal(m []byte) error

Unmarshal deserializes an eon public key from the given byte slice.

func (*EonPublicKey) UnmarshalText 

func (eonPublicKey *EonPublicKey) UnmarshalText(input []byte) error

UnmarshalText deserializes the eon public key from hex.

type EonPublicKeyShare 

type EonPublicKeyShare blst.P2Affine

EonPublicKeyShare represents a share of the eon public key.

func ComputeEonPublicKeyShare 

func ComputeEonPublicKeyShare(keyperIndex int, gammas []*Gammas) *EonPublicKeyShare

ComputeEonPublicKeyShare computes the eon public key share of the given keyper.

func (*EonPublicKeyShare) Equal 

func (eonPublicKeyShare *EonPublicKeyShare) Equal(pk2 *EonPublicKeyShare) bool

func (*EonPublicKeyShare) GobDecode 

func (eonPublicKeyShare *EonPublicKeyShare) GobDecode(data []byte) error

func (*EonPublicKeyShare) GobEncode 

func (eonPublicKeyShare *EonPublicKeyShare) GobEncode() ([]byte, error)

func (*EonPublicKeyShare) Marshal 

func (eonPublicKeyShare *EonPublicKeyShare) Marshal() []byte

Marshal serializes the eon public key share.

func (*EonPublicKeyShare) Unmarshal 

func (eonPublicKeyShare *EonPublicKeyShare) Unmarshal(m []byte) error

Unmarshal deserializes an eon public key share.

type EonSecretKeyShare 

type EonSecretKeyShare big.Int

EonSecretKeyShare represents a share of the eon secret key.

func ComputeEonSecretKeyShare 

func ComputeEonSecretKeyShare(polyEvals []*big.Int) *EonSecretKeyShare

ComputeEonSecretKeyShare computes the keyper's secret key share from the set of poly evals received from the other keypers.

func (*EonSecretKeyShare) Equal 

func (eonSecretKeyShare *EonSecretKeyShare) Equal(e2 *EonSecretKeyShare) bool

func (*EonSecretKeyShare) GobDecode 

func (eonSecretKeyShare *EonSecretKeyShare) GobDecode(data []byte) error

func (*EonSecretKeyShare) GobEncode 

func (eonSecretKeyShare *EonSecretKeyShare) GobEncode() ([]byte, error)

func (*EonSecretKeyShare) Marshal 

func (eonSecretKeyShare *EonSecretKeyShare) Marshal() []byte

Marshal serializes the eon secret key share.

func (*EonSecretKeyShare) Unmarshal 

func (eonSecretKeyShare *EonSecretKeyShare) Unmarshal(m []byte) error

Unarshal deserializes an eon secret key share.

type EpochID 

type EpochID blst.P1Affine

EpochID is the identifier of an epoch.

func ComputeEpochID 

func ComputeEpochID(epochIDBytes []byte) *EpochID

ComputeEpochID computes the id of the given epoch.

func (*EpochID) Equal 

func (epochID *EpochID) Equal(g2 *EpochID) bool

func (*EpochID) GobDecode 

func (epochID *EpochID) GobDecode(data []byte) error

func (*EpochID) GobEncode 

func (epochID *EpochID) GobEncode() ([]byte, error)

func (*EpochID) Marshal 

func (epochID *EpochID) Marshal() []byte

Marshal serializes the epoch id.

func (*EpochID) Unmarshal 

func (epochID *EpochID) Unmarshal(m []byte) error

Unmarshal deserializes an epoch id.

type EpochSecretKey 

type EpochSecretKey blst.P1Affine

EpochSecretKey represents an epoch secret key.

func ComputeEpochSecretKey 

func ComputeEpochSecretKey(keyperIndices []int, epochSecretKeyShares []*EpochSecretKeyShare, threshold uint64) (*EpochSecretKey, error)

ComputeEpochSecretKey computes the epoch secret key from a set of shares.

func (*EpochSecretKey) Equal 

func (epochSecretKey *EpochSecretKey) Equal(g2 *EpochSecretKey) bool

func (*EpochSecretKey) GobDecode 

func (epochSecretKey *EpochSecretKey) GobDecode(data []byte) error

func (*EpochSecretKey) GobEncode 

func (epochSecretKey *EpochSecretKey) GobEncode() ([]byte, error)

func (*EpochSecretKey) Marshal 

func (epochSecretKey *EpochSecretKey) Marshal() []byte

Marshal serializes the epoch secret key.

func (EpochSecretKey) MarshalText 

func (epochSecretKey EpochSecretKey) MarshalText() ([]byte, error)

MarshalText serializes the epoch secret key to hex.

func (*EpochSecretKey) Unmarshal 

func (epochSecretKey *EpochSecretKey) Unmarshal(m []byte) error

Unmarshal deserializes an epoch secret key.

func (*EpochSecretKey) UnmarshalText 

func (epochSecretKey *EpochSecretKey) UnmarshalText(input []byte) error

UnmarshalText deserializes the epoch secret key from hex.

type EpochSecretKeyShare 

type EpochSecretKeyShare blst.P1Affine

EpochSecretKeyShare represents a keyper's share of the epoch sk key.

func ComputeEpochSecretKeyShare 

func ComputeEpochSecretKeyShare(eonSecretKeyShare *EonSecretKeyShare, epochID *EpochID) *EpochSecretKeyShare

ComputeEpochSecretKeyShare computes a keyper's epoch sk share.

func (*EpochSecretKeyShare) Equal 

func (epochSecretKeyShare *EpochSecretKeyShare) Equal(g2 *EpochSecretKeyShare) bool

func (*EpochSecretKeyShare) GobDecode 

func (epochSecretKeyShare *EpochSecretKeyShare) GobDecode(data []byte) error

func (*EpochSecretKeyShare) GobEncode 

func (epochSecretKeyShare *EpochSecretKeyShare) GobEncode() ([]byte, error)

func (*EpochSecretKeyShare) Marshal 

func (epochSecretKeyShare *EpochSecretKeyShare) Marshal() []byte

Marshal serializes the epoch secret key share.

func (*EpochSecretKeyShare) Unmarshal 

func (epochSecretKeyShare *EpochSecretKeyShare) Unmarshal(m []byte) error

Unmarshal deserializes an epoch secret key share.

type Gammas 

type Gammas []*blst.P2Affine

Gammas is a sequence of G2 points based on a polynomial.

func ZeroGammas 

func ZeroGammas(degree uint64) *Gammas

ZeroGammas returns the zero value for gammas.

func (*Gammas) Degree 

func (g *Gammas) Degree() uint64

Degree returns the degree of the underlying polynomial.

func (Gammas) Equal 

func (g Gammas) Equal(otherG Gammas) bool

func (*Gammas) GobDecode 

func (g *Gammas) GobDecode(data []byte) error

GobDecode decodes a Gammas value. See https://golang.org/pkg/encoding/gob/#GobDecoder

func (*Gammas) GobEncode 

func (g *Gammas) GobEncode() ([]byte, error)

GobEncode encodes a Gammas value. See https://golang.org/pkg/encoding/gob/#GobEncoder

func (*Gammas) Marshal 

func (g *Gammas) Marshal() []byte

Marshal serializes the gammas value.

Serialization format: [n:4][gamma1:96]...[gamman:96]

func (*Gammas) MarshalText 

func (g *Gammas) MarshalText() ([]byte, error)

MarshalText serializes the gammas as hex.

func (*Gammas) Pi 

func (g *Gammas) Pi(xi *big.Int) *blst.P2Affine

Pi computes the pi value at the given x coordinate.

func (*Gammas) Unmarshal 

func (g *Gammas) Unmarshal(m []byte) error

Unmarshal deserializes a gammas value.

func (*Gammas) UnmarshalText 

func (g *Gammas) UnmarshalText(b []byte) error

UnmarshalText deserializes the gammas from hex.

type LagrangeCoeffs 

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

LagrangeCoeffs stores the lagrange coefficients that are needed to compute an epoch secret key for a certain array of keypers. We use this to speedup epoch secret key generation.

func NewLagrangeCoeffs 

func NewLagrangeCoeffs(keyperIndices []int) *LagrangeCoeffs

NewLagrangeCoeffs computes the lagrange coefficients for the given array of keypers.

func (*LagrangeCoeffs) ComputeEpochSecretKey 

func (lc *LagrangeCoeffs) ComputeEpochSecretKey(epochSecretKeyShares []*EpochSecretKeyShare) (*EpochSecretKey, error)

ComputeEpochSecretKey computes the epoch secret key given the secret key shares of the keypers. The caller has to ensure that the secret shares match the keyperIndices used during initialisation.

type Polynomial 

type Polynomial []*big.Int

Polynomial represents a polynomial over Z_q.

func NewPolynomial 

func NewPolynomial(coefficients []*big.Int) (*Polynomial, error)

NewPolynomial creates a new polynomial from the given coefficients. It verifies the number and range of them.

func RandomPolynomial 

func RandomPolynomial(r io.Reader, degree uint64) (*Polynomial, error)

RandomPolynomial generates a random polynomial of given degree.

func (*Polynomial) Degree 

func (p *Polynomial) Degree() uint64

Degree returns the degree of the polynomial.

func (*Polynomial) Eval 

func (p *Polynomial) Eval(x *big.Int) *big.Int

Eval evaluates the polynomial at the given coordinate.

func (*Polynomial) EvalForKeyper 

func (p *Polynomial) EvalForKeyper(keyperIndex int) *big.Int

EvalForKeyper evaluates the polynomial at the position designated for the given keyper.

func (*Polynomial) Gammas 

func (p *Polynomial) Gammas() *Gammas

Gammas computes the gamma values for a given polynomial.

Source Files

View all Source files

Jump to

Keyboard shortcuts

? : This menu
/ : Search site
f or F : Jump to
y or Y : Canonical URL
go.dev uses cookies from Google to deliver and enhance the quality of its services and to analyze traffic. Learn more.