@mysten/sui
Version:
Sui TypeScript API
142 lines (140 loc) • 4.53 kB
JavaScript
import { PasskeyAuthenticator } from "../../bcs/bcs.mjs";
import { SIGNATURE_SCHEME_TO_FLAG } from "../../cryptography/signature-scheme.mjs";
import { PublicKey, bytesEqual } from "../../cryptography/publickey.mjs";
import { fromBase64, toBase64 } from "@mysten/bcs";
import { p256 } from "@noble/curves/nist.js";
import { sha256 } from "@noble/hashes/sha2.js";
//#region src/keypairs/passkey/publickey.ts
const PASSKEY_PUBLIC_KEY_SIZE = 33;
const PASSKEY_UNCOMPRESSED_PUBLIC_KEY_SIZE = 65;
const PASSKEY_SIGNATURE_SIZE = 64;
/** Fixed DER header for secp256r1 SubjectPublicKeyInfo
DER structure for P-256 SPKI:
30 -- SEQUENCE
59 -- length (89 bytes)
30 -- SEQUENCE
13 -- length (19 bytes)
06 -- OBJECT IDENTIFIER
07 -- length
2A 86 48 CE 3D 02 01 -- id-ecPublicKey
06 -- OBJECT IDENTIFIER
08 -- length
2A 86 48 CE 3D 03 01 07 -- secp256r1/prime256v1
03 -- BIT STRING
42 -- length (66 bytes)
00 -- padding
===== above bytes are considered header =====
04 || x || y -- uncompressed point (65 bytes: 0x04 || 32-byte x || 32-byte y)
*/
const SECP256R1_SPKI_HEADER = new Uint8Array([
48,
89,
48,
19,
6,
7,
42,
134,
72,
206,
61,
2,
1,
6,
8,
42,
134,
72,
206,
61,
3,
1,
7,
3,
66,
0
]);
/**
* A passkey public key
*/
var PasskeyPublicKey = class extends PublicKey {
static {
this.SIZE = PASSKEY_PUBLIC_KEY_SIZE;
}
/**
* Create a new PasskeyPublicKey object
* @param value passkey public key as buffer or base-64 encoded string
*/
constructor(value) {
super();
if (typeof value === "string") this.data = fromBase64(value);
else if (value instanceof Uint8Array) this.data = value;
else this.data = Uint8Array.from(value);
if (this.data.length !== PASSKEY_PUBLIC_KEY_SIZE) throw new Error(`Invalid public key input. Expected ${PASSKEY_PUBLIC_KEY_SIZE} bytes, got ${this.data.length}`);
}
/**
* Checks if two passkey public keys are equal
*/
equals(publicKey) {
return super.equals(publicKey);
}
/**
* Return the byte array representation of the Secp256r1 public key
*/
toRawBytes() {
return this.data;
}
/**
* Return the Sui address associated with this Secp256r1 public key
*/
flag() {
return SIGNATURE_SCHEME_TO_FLAG["Passkey"];
}
/**
* Verifies that the signature is valid for for the provided message
*/
async verify(message, signature) {
const parsed = parseSerializedPasskeySignature(signature);
const clientDataJSON = JSON.parse(parsed.clientDataJson);
if (clientDataJSON.type !== "webauthn.get") return false;
if (!bytesEqual(message, fromBase64(clientDataJSON.challenge.replace(/-/g, "+").replace(/_/g, "/")))) return false;
const pk = parsed.userSignature.slice(1 + PASSKEY_SIGNATURE_SIZE);
if (!bytesEqual(this.toRawBytes(), pk)) return false;
const payload = new Uint8Array([...parsed.authenticatorData, ...sha256(new TextEncoder().encode(parsed.clientDataJson))]);
const sig = parsed.userSignature.slice(1, PASSKEY_SIGNATURE_SIZE + 1);
return p256.verify(sig, payload, pk);
}
};
/**
* Parses a DER SubjectPublicKeyInfo into an uncompressed public key. This also verifies
* that the curve used is P-256 (secp256r1).
*
* @param data: DER SubjectPublicKeyInfo
* @returns uncompressed public key (`0x04 || x || y`)
*/
function parseDerSPKI(derBytes) {
if (derBytes.length !== SECP256R1_SPKI_HEADER.length + PASSKEY_UNCOMPRESSED_PUBLIC_KEY_SIZE) throw new Error("Invalid DER length");
for (let i = 0; i < SECP256R1_SPKI_HEADER.length; i++) if (derBytes[i] !== SECP256R1_SPKI_HEADER[i]) throw new Error("Invalid spki header");
if (derBytes[SECP256R1_SPKI_HEADER.length] !== 4) throw new Error("Invalid point marker");
return derBytes.slice(SECP256R1_SPKI_HEADER.length);
}
/**
* Parse signature from bytes or base64 string into the following fields.
*/
function parseSerializedPasskeySignature(signature) {
const bytes = typeof signature === "string" ? fromBase64(signature) : signature;
if (bytes[0] !== SIGNATURE_SCHEME_TO_FLAG.Passkey) throw new Error("Invalid signature scheme");
const dec = PasskeyAuthenticator.parse(bytes.slice(1));
return {
signatureScheme: "Passkey",
serializedSignature: toBase64(bytes),
signature: bytes,
authenticatorData: dec.authenticatorData,
clientDataJson: dec.clientDataJson,
userSignature: new Uint8Array(dec.userSignature),
publicKey: new Uint8Array(dec.userSignature.slice(1 + PASSKEY_SIGNATURE_SIZE))
};
}
//#endregion
export { PASSKEY_PUBLIC_KEY_SIZE, PASSKEY_SIGNATURE_SIZE, PasskeyPublicKey, parseDerSPKI, parseSerializedPasskeySignature };
//# sourceMappingURL=publickey.mjs.map