EcdsaSignature
Constructors
new EcdsaSignature(signature)
new EcdsaSignature(signature: {
r: number | bigint | Field3 | AlmostForeignField;
s: number | bigint | Field3 | AlmostForeignField;
}): EcdsaSignature
Create a new EcdsaSignature from an object containing the scalars r and s.
Parameters
• signature
• signature.r: number | bigint | Field3 | AlmostForeignField
• signature.s: number | bigint | Field3 | AlmostForeignField
Returns
Source
lib/provable/crypto/foreign-ecdsa.ts:37
Properties
r
r: AlmostForeignField;
Source
lib/provable/crypto/foreign-ecdsa.ts:30
s
s: AlmostForeignField;
Source
lib/provable/crypto/foreign-ecdsa.ts:31
_Curve?
static optional _Curve: typeof ForeignCurve;
Source
lib/provable/crypto/foreign-ecdsa.ts:164
_provable?
static optional _provable: ProvablePureExtended<EcdsaSignature, {
r: string;
s: string;
}>;
Source
lib/provable/crypto/foreign-ecdsa.ts:165
Accessors
Constructor
get Constructor(): typeof EcdsaSignature
Returns
typeof EcdsaSignature
Source
lib/provable/crypto/foreign-ecdsa.ts:161
Curve
get static Curve(): typeof ForeignCurve
The ForeignCurve on which the ECDSA signature is defined.
Returns
typeof ForeignCurve
Source
lib/provable/crypto/foreign-ecdsa.ts:173
provable
get static provable(): ProvablePureExtended<EcdsaSignature, {
r: string;
s: string;
}>
Provable<EcdsaSignature>
Returns
ProvablePureExtended\<EcdsaSignature, {
r: string;
s: string;
}>
Source
lib/provable/crypto/foreign-ecdsa.ts:180
Methods
toBigInt()
toBigInt(): {
r: bigint;
s: bigint;
}
Convert this signature to an object with bigint fields.
Returns
{
r: bigint;
s: bigint;
}
r
r: bigint;
s
s: bigint;
Source
lib/provable/crypto/foreign-ecdsa.ts:65
verify()
verify(message: Bytes, publicKey: FlexiblePoint): Bool
Verify the ECDSA signature given the message (an array of bytes) and public key (a Curve point).
Important: This method returns a Bool which indicates whether the signature is valid. So, to actually prove validity of a signature, you need to assert that the result is true.
Parameters
• message: Bytes
• publicKey: FlexiblePoint
Returns
Throws
if one of the signature scalars is zero or if the public key is not on the curve.
Example
// create classes for your curve
class Secp256k1 extends createForeignCurve(Crypto.CurveParams.Secp256k1) {}
class Scalar extends Secp256k1.Scalar {}
class Ecdsa extends createEcdsa(Secp256k1) {}
let message = 'my message';
let messageBytes = new TextEncoder().encode(message);
// outside provable code: create inputs
let privateKey = Scalar.random();
let publicKey = Secp256k1.generator.scale(privateKey);
let signature = Ecdsa.sign(messageBytes, privateKey.toBigInt());
// ...
// in provable code: create input witnesses (or use method inputs, or constants)
let pk = Provable.witness(Secp256k1.provable, () => publicKey);
let msg = Provable.witness(Provable.Array(Field, 9), () => messageBytes.map(Field));
let sig = Provable.witness(Ecdsa.provable, () => signature);
// verify signature
let isValid = sig.verify(msg, pk);
isValid.assertTrue('signature verifies');
Source
lib/provable/crypto/foreign-ecdsa.ts:103
verifySignedHash()
verifySignedHash(msgHash: bigint | AlmostForeignField, publicKey: FlexiblePoint): Bool
Verify the ECDSA signature given the message hash (a Scalar) and public key (a Curve point).
This is a building block of EcdsaSignature.verify, where the input message is also hashed. In contrast, this method just takes the message hash (a curve scalar) as input, giving you flexibility in choosing the hashing algorithm.
Parameters
• msgHash: bigint | AlmostForeignField
• publicKey: FlexiblePoint
Returns
Source
lib/provable/crypto/foreign-ecdsa.ts:116
check()
static check(signature: EcdsaSignature): void
Parameters
• signature: EcdsaSignature
Returns
void
Source
lib/provable/crypto/foreign-ecdsa.ts:155
from()
static from(signature: FlexibleSignature): EcdsaSignature
Coerce the input to a EcdsaSignature.
Parameters
• signature: FlexibleSignature
Returns
Source
lib/provable/crypto/foreign-ecdsa.ts:48
fromHex()
static fromHex(rawSignature: string): EcdsaSignature
Create an EcdsaSignature from a raw 130-char hex string as used in Ethereum transactions.
Parameters
• rawSignature: string
Returns
Source
lib/provable/crypto/foreign-ecdsa.ts:57
sign()
static sign(message: Uint8Array | (number | bigint)[], privateKey: bigint): EcdsaSignature
Create an EcdsaSignature by signing a message with a private key.
Note: This method is not provable, and only takes JS bigints as input.
Parameters
• message: Uint8Array | (number | bigint)[]
• privateKey: bigint
Returns
Source
lib/provable/crypto/foreign-ecdsa.ts:135
signHash()
static signHash(msgHash: bigint, privateKey: bigint): EcdsaSignature
Create an EcdsaSignature by signing a message hash with a private key.
This is a building block of EcdsaSignature.sign, where the input message is also hashed. In contrast, this method just takes the message hash (a curve scalar) as input, giving you flexibility in choosing the hashing algorithm.
Note: This method is not provable, and only takes JS bigints as input.
Parameters
• msgHash: bigint
• privateKey: bigint