checkJsonSignature method

bool checkJsonSignature(
  1. String key,
  2. String userId,
  3. String deviceId
)

Checks the signature of a signed json object.

Implementation

bool checkJsonSignature(String key, String userId, String deviceId) {
  final signatures = this['signatures'];
  if (signatures == null ||
      signatures is! Map<String, dynamic> ||
      !signatures.containsKey(userId)) {
    return false;
  }
  remove('unsigned');
  remove('signatures');
  if (!signatures[userId].containsKey('ed25519:$deviceId')) return false;
  final String signature = signatures[userId]['ed25519:$deviceId'];
  final canonical = canonicalJson.encode(this);
  final message = String.fromCharCodes(canonical);
  var isValid = false;
  final olmutil = olm.Utility();
  try {
    olmutil.ed25519_verify(key, message, signature);
    isValid = true;
  } catch (e, s) {
    isValid = false;
    Logs().w('[LibOlm] Signature check failed', e, s);
  } finally {
    olmutil.free();
  }
  return isValid;
}