Implement WebAuthn auth for minting PKP and storing encryption condition (#2)

* Implement WebAuthn auth for minting PKP and storing encryption condition

* Update copy

* Update copy

src/utils/decodeAttestationObject.ts

@@ -0,0 +1,39 @@
+// copy-🍝 from https://github.com/MasterKale/SimpleWebAuthn/blob/33528afe001d4aca62052dce204c0398c3127ffd/packages/server/src/helpers/decodeAttestationObject.ts#L8
+
+/**
+ * Convert an AttestationObject buffer to a proper object
+ *
+ * @param base64AttestationObject Attestation Object buffer
+ */
+export function decodeAttestationObject(
+	cbor: any,
+	attestationObject: Buffer
+): AttestationObject {
+	const toCBOR: AttestationObject = cbor.decodeAllSync(attestationObject)[0];
+	return toCBOR;
+}
+
+export type AttestationFormat =
+	| "fido-u2f"
+	| "packed"
+	| "android-safetynet"
+	| "android-key"
+	| "tpm"
+	| "apple"
+	| "none";
+
+export type AttestationObject = {
+	fmt: AttestationFormat;
+	attStmt: AttestationStatement;
+	authData: Buffer;
+};
+
+export type AttestationStatement = {
+	sig?: Buffer;
+	x5c?: Buffer[];
+	response?: Buffer;
+	alg?: number;
+	ver?: string;
+	certInfo?: Buffer;
+	pubArea?: Buffer;
+};