Links: API, Classes, Functions, Variables
| decrypt |
| encrypt |
| sign |
| verify |
Links: API, Classes, Functions, Variables
decrypt = (message: number[], recipient: PrivateKey): number[] => {
const reader = new Reader(message);
const messageVersion = toHex(reader.read(4));
if (messageVersion !== VERSION) {
throw new Error(`Message version mismatch: Expected ${VERSION}, received ${messageVersion}`);
}
const sender = PublicKey.fromString(toHex(reader.read(33)));
const expectedRecipientDER = toHex(reader.read(33));
const actualRecipientDER = recipient
.toPublicKey()
.encode(true, "hex") as string;
if (expectedRecipientDER !== actualRecipientDER) {
throw new Error(`The encrypted message expects a recipient public key of ${expectedRecipientDER}, but the provided key is ${actualRecipientDER}`);
}
const keyID = toBase64(reader.read(32));
const encrypted = reader.read(reader.bin.length - reader.pos);
const invoiceNumber = `2-message encryption-${keyID}`;
const signingPriv = sender.deriveChild(recipient, invoiceNumber);
const recipientPub = recipient.deriveChild(sender, invoiceNumber);
const sharedSecret = signingPriv.deriveSharedSecret(recipientPub);
const symmetricKey = new SymmetricKey(sharedSecret.encode(true).slice(1));
return symmetricKey.decrypt(encrypted) as number[];
}
See also: PrivateKey, PublicKey, Reader, SymmetricKey, encode, toBase64, toHex
Links: API, Classes, Functions, Variables
encrypt = (message: number[], sender: PrivateKey, recipient: PublicKey): number[] => {
const keyID = Random(32);
const keyIDBase64 = toBase64(keyID);
const invoiceNumber = `2-message encryption-${keyIDBase64}`;
const signingPriv = sender.deriveChild(recipient, invoiceNumber);
const recipientPub = recipient.deriveChild(sender, invoiceNumber);
const sharedSecret = signingPriv.deriveSharedSecret(recipientPub);
const symmetricKey = new SymmetricKey(sharedSecret.encode(true).slice(1));
const encrypted = symmetricKey.encrypt(message) as number[];
const senderPublicKey = sender.toPublicKey().encode(true);
const version = toArray(VERSION, "hex");
return [
...version,
...senderPublicKey,
...recipient.encode(true),
...keyID,
...encrypted
];
}
See also: PrivateKey, PublicKey, SymmetricKey, encode, toArray, toBase64
Links: API, Classes, Functions, Variables
sign = (message: number[], signer: PrivateKey, verifier?: PublicKey): number[] => {
const recipientAnyone = typeof verifier !== "object";
if (recipientAnyone) {
const curve = new Curve();
const anyone = new PrivateKey(1);
const anyonePoint = curve.g.mul(anyone);
verifier = new PublicKey(anyonePoint.x, anyonePoint.y);
}
const keyID = Random(32);
const keyIDBase64 = toBase64(keyID);
const invoiceNumber = `2-message signing-${keyIDBase64}`;
const signingKey = signer.deriveChild(verifier, invoiceNumber);
const signature = signingKey.sign(message).toDER();
const senderPublicKey = signer.toPublicKey().encode(true);
const version = toArray(VERSION, "hex");
return [
...version,
...senderPublicKey,
...(recipientAnyone ? [0] : verifier.encode(true)),
...keyID,
...signature
];
}
See also: Curve, PrivateKey, PublicKey, encode, toArray, toBase64
Links: API, Classes, Functions, Variables
verify = (message: number[], sig: number[], recipient?: PrivateKey): boolean => {
const reader = new Reader(sig);
const messageVersion = toHex(reader.read(4));
if (messageVersion !== VERSION) {
throw new Error(`Message version mismatch: Expected ${VERSION}, received ${messageVersion}`);
}
const signer = PublicKey.fromString(toHex(reader.read(33)));
const [verifierFirst] = reader.read(1);
if (verifierFirst === 0) {
recipient = new PrivateKey(1);
}
else {
const verifierRest = reader.read(32);
const verifierDER = toHex([verifierFirst, ...verifierRest]);
if (typeof recipient !== "object") {
throw new Error(`This signature can only be verified with knowledge of a specific private key. The associated public key is: ${verifierDER}`);
}
const recipientDER = recipient.toPublicKey().encode(true, "hex") as string;
if (verifierDER !== recipientDER) {
throw new Error(`The recipient public key is ${recipientDER} but the signature requres the recipient to have public key ${verifierDER}`);
}
}
const keyID = toBase64(reader.read(32));
const signatureDER = toHex(reader.read(reader.bin.length - reader.pos));
const signature = Signature.fromDER(signatureDER, "hex");
const invoiceNumber = `2-message signing-${keyID}`;
const signingKey = signer.deriveChild(recipient, invoiceNumber);
const verified = signingKey.verify(message, signature);
return verified;
}
See also: PrivateKey, PublicKey, Reader, Signature, encode, toBase64, toHex
Links: API, Classes, Functions, Variables