EcdsaSignature
Defined in: lib/provable/crypto/foreign-ecdsa.ts:25
Constructors
new EcdsaSignature()
new EcdsaSignature(signature: {
r: number | bigint | Field3 | AlmostForeignField;
s: number | bigint | Field3 | AlmostForeignField;
}): EcdsaSignature
Defined in: lib/provable/crypto/foreign-ecdsa.ts:34
Create a new EcdsaSignature from an object containing the scalars r and s.
Note: Inputs must be range checked if they originate from a different field with a different modulus or if they are not constants. Please refer to the ForeignField constructor comments for more details.
Parameters
signature
r
number | bigint | Field3 | AlmostForeignField
s
number | bigint | Field3 | AlmostForeignField
Returns
Properties
r
r: AlmostForeignField;
Defined in: lib/provable/crypto/foreign-ecdsa.ts:26
s
s: AlmostForeignField;
Defined in: lib/provable/crypto/foreign-ecdsa.ts:27
_Curve?
static optional _Curve: typeof ForeignCurve;
Defined in: lib/provable/crypto/foreign-ecdsa.ts:215
_provable?
static optional _provable: ProvablePureExtended<EcdsaSignature, {
r: bigint;
s: bigint;
}, {
r: string;
s: string;
}>;
Defined in: lib/provable/crypto/foreign-ecdsa.ts:216
Accessors
Constructor
Get Signature
get Constructor(): typeof EcdsaSignature
Defined in: lib/provable/crypto/foreign-ecdsa.ts:212
Returns
typeof EcdsaSignature
Curve
Get Signature
get static Curve(): typeof ForeignCurve
Defined in: lib/provable/crypto/foreign-ecdsa.ts:225
The ForeignCurve on which the ECDSA signature is defined.
Returns
typeof ForeignCurve
provable
Get Signature
get static provable(): ProvablePureExtended<EcdsaSignature, {
r: bigint;
s: bigint;
}, {
r: string;
s: string;
}>
Defined in: lib/provable/crypto/foreign-ecdsa.ts:232
Provable<EcdsaSignature>
Returns
ProvablePureExtended<EcdsaSignature, {
r: bigint;
s: bigint;
}, {
r: string;
s: string;
}>
Methods
toBigInt()
toBigInt(): {
r: bigint;
s: bigint;
}
Defined in: lib/provable/crypto/foreign-ecdsa.ts:62
Convert this signature to an object with bigint fields.
Returns
{
r: bigint;
s: bigint;
}
r
r: bigint;
s
s: bigint;
verify()
verify(message: Bytes, publicKey: FlexiblePoint): Bool
Defined in: lib/provable/crypto/foreign-ecdsa.ts:100
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
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, () => publicKey);
let msg = Provable.witness(Provable.Array(Field, 9), () => messageBytes.map(Field));
let sig = Provable.witness(Ecdsa, () => signature);
// verify signature
let isValid = sig.verify(msg, pk);
isValid.assertTrue('signature verifies');
verifyEthers()
verifyEthers(message: Bytes, publicKey: FlexiblePoint): Bool
Defined in: lib/provable/crypto/foreign-ecdsa.ts:145
Verify an ECDSA signature generated by the ethers.js library, given the message (as a byte array) and a public key (a Curve point). The message digest used for signing follows the format defined in EIP-191, with the Ethereum-specific prefix.
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.
Note: This method is specifically designed to verify signatures generated by ethers.js. Ensure that the curve being used is Secp256k1, as demonstrated in the example.
Parameters
message
Bytes
The original message as a byte array.
publicKey
The public key as a point on the Secp256k1 elliptic curve.
Returns
- A Bool indicating the validity of the signature.
Throws
An error will be thrown if one of the signature scalars is zero or if the public key does not lie on the curve.
Example
import { Wallet } from 'ethers';
// create the class for Secp256k1 curve
class Secp256k1 extends createForeignCurve(Crypto.CurveParams.Secp256k1) {}
class Ecdsa extends createEcdsa(Secp256k1) {}
// outside provable code: create inputs
let message = 'my message';
let signatureRaw = await wallet.signMessage(message);
let compressedPublicKey = wallet.signingKey.compressedPublicKey;
// this also works for uncompressed public keys (wallet.signingKey.publicKey)
let publicKey = Secp256k1.fromEthers(compressedPublicKey.slice(2));
let signature = Ecdsa.fromHex(signatureRaw);
// ...
// in provable code: create input witnesses (or use method inputs, or constants)
// and verify the signature
let isValid = signature.verifyEthers(Bytes.fromString(message), publicKey);
isValid.assertTrue('signature verifies');
verifySignedHash()
verifySignedHash(msgHash: bigint | Bytes | AlmostForeignField, publicKey: FlexiblePoint): Bool
Defined in: lib/provable/crypto/foreign-ecdsa.ts:162
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, or the output bytes of a hash function) as input, giving you flexibility in choosing the hashing algorithm.
Parameters
msgHash
bigint | Bytes | AlmostForeignField
publicKey
Returns
check()
static check(signature: EcdsaSignature): void
Defined in: lib/provable/crypto/foreign-ecdsa.ts:204
Parameters
signature
Returns
void
from()
static from(signature: FlexibleSignature): EcdsaSignature
Defined in: lib/provable/crypto/foreign-ecdsa.ts:45
Coerce the input to a EcdsaSignature.
Parameters
signature
FlexibleSignature
Returns
fromHex()
static fromHex(rawSignature: string): EcdsaSignature
Defined in: lib/provable/crypto/foreign-ecdsa.ts:54
Create an EcdsaSignature from a raw 130-char hex string as used in Ethereum transactions.
Parameters
rawSignature
string
Returns
sign()
static sign(message: Uint8Array | (number | bigint)[], privateKey: bigint): EcdsaSignature
Defined in: lib/provable/crypto/foreign-ecdsa.ts:181
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
signHash()
static signHash(msgHash: bigint | Bytes, privateKey: bigint): EcdsaSignature
Defined in: lib/provable/crypto/foreign-ecdsa.ts:196
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, or the output bytes of a hash function) as input, giving you flexibility in choosing the hashing algorithm.
Note: This method is not provable, and only takes JS bigints or constant Bytes as input.
Parameters
msgHash
bigint | Bytes
privateKey
bigint