public static bool Verify()

in net/JetBrains.DownloadPgpVerifier/src/PgpSignaturesVerifier.cs [17:78]
52 lines of code
14 McCabe index (conditional complexity)

    public static bool Verify(
      Stream masterPublicKeyStream,
      Stream publicKeysStream,
      Stream signaturesStream,
      Stream dataStream,
      ILogger logger)
    {
      if (dataStream == null) throw new ArgumentNullException(nameof(dataStream));
      if (logger == null) throw new ArgumentNullException(nameof(logger));
      var pos = dataStream.CanSeek ? dataStream.Position : throw new ArgumentException("The data stream must be seek-able", nameof(dataStream));
      logger.Info("Verify");

      var masterPublicKey = GetTrustedMasterPublicKey(masterPublicKeyStream);
      var publicKeyRingBundle = GetUntrustedPublicKeyRingBundle(publicKeysStream);
      var buffer = new byte[16 * 1024];
      foreach (var signature in GetSignatures(signaturesStream))
        if (signature.SignatureType is PgpSignature.BinaryDocument)
        {
          void LogWarning(string str) => logger.Warning($"The signature SignKeyID={signature.KeyId:X16} was skipped: {str}");

          if (!CheckSignatureFormat(signature, LogWarning))
            continue;

          var publicKey = publicKeyRingBundle.GetPublicKey(signature.KeyId);
          if (publicKey == null)
          {
            LogWarning("No public key for signature");
            continue;
          }

          if (!CheckPublicKeyFormat(publicKey, LogWarning))
            continue;

          if (!IsSubKeyForSigning(masterPublicKey, publicKey, LogWarning))
            continue;

          if (!IsSubKeyRevoked(masterPublicKey, publicKey, signature, LogWarning))
            continue;

          signature.InitVerify(publicKey);
          dataStream.Position = pos;
          while (true)
          {
            var received = dataStream.Read(buffer, 0, buffer.Length);
            if (received == 0)
              break;
            signature.Update(buffer, 0, received);
          }

          if (!signature.Verify())
          {
            LogWarning("Invalid signature verification.");
            continue;
          }

          logger.Info($"Success for SignKeyID={signature.KeyId:X16}");
          return true;
        }

      logger.Error("Failed to verify signature");
      return false;
    }