Function checkContentSig

src/note.ts:117–143

(
  content: Buffer,
  signature: string,
  publicKey: string
)

// Check signature to prevent data forgery, return true or false
export function checkContentSig(
  content: Buffer,
  signature: string,
  publicKey: string
) {
  // NOTE v2.0 signature check. A compressed signature
  const msg = new bitcore.Message(content.toString("hex"));
  // Get output signature
  const isValid = msg._verify(
    new bitcore.PublicKey(publicKey),
    bitcore.crypto.Signature.fromCompact(Buffer.from(signature, "hex"))
  );
  if (isValid) {
    return true;
  }
  // NOTE v1.0 signature check. An uncompressed signature
  const hash = hash256(content);
  const sig = bitcore.crypto.Signature.fromCompact(
    Buffer.from(signature, "hex")
  );
  // Verify signature using root address public key to ensure transaction is not forged
  return bitcore.crypto.ECDSA.verify(
    hash,
    sig,
    new bitcore.PublicKey(publicKey)
  );
}

// Build note payload, if singleMode=true, put all data in data0
export function buildNotePayload(data: string | object, singleMode = false) {