Function check

lib/internal/crypto/webcrypto.js:1770–1870

(op, alg, length)

}

function check(op, alg, length) {
  if (op === 'encapsulateBits' || op === 'encapsulateKey') {
    op = 'encapsulate';
  }

  if (op === 'decapsulateBits' || op === 'decapsulateKey') {
    op = 'decapsulate';
  }

  let normalizedAlgorithm;
  try {
    normalizedAlgorithm = normalizeAlgorithm(alg, op);
  } catch {
    if (op === 'wrapKey') {
      return check('encrypt', alg);
    }

    if (op === 'unwrapKey') {
      return check('decrypt', alg);
    }

    return false;
  }

  switch (op) {
    case 'decapsulate':
    case 'decrypt':
    case 'digest': {
      if ((normalizedAlgorithm.name === 'cSHAKE128' ||
           normalizedAlgorithm.name === 'cSHAKE256') &&
          (normalizedAlgorithm.functionName?.byteLength ||
           normalizedAlgorithm.customization?.byteLength)) {
        return CShakeJob !== undefined;
      }
      return true;
    }
    case 'encapsulate':
    case 'encrypt':
    case 'exportKey':
    case 'importKey':
    case 'sign':
    case 'unwrapKey':
    case 'verify':
    case 'wrapKey':
      return true;
    case 'deriveBits': {
      if (normalizedAlgorithm.name === 'HKDF') {
        require('internal/crypto/hkdf').validateHkdfDeriveBitsLength(length);
      }

      if (normalizedAlgorithm.name === 'PBKDF2') {
        require('internal/crypto/pbkdf2').validatePbkdf2DeriveBitsLength(length);
      }

      if (StringPrototypeStartsWith(normalizedAlgorithm.name, 'Argon2')) {
        require('internal/crypto/argon2').validateArgon2DeriveBitsLength(length);
      }