예제 #1
0
        public override bool TryParse(string epasaText, out EPasa epasa, out EPasaErrorCode errorCode)
        {
            errorCode = EPasaErrorCode.Success;
            epasa     = new EPasa();

            if (string.IsNullOrEmpty(epasaText))
            {
                errorCode = EPasaErrorCode.BadFormat;
                return(false);
            }

            var match                 = _epasaRegex.Match(epasaText);
            var checksumDelim         = match.Groups["ChecksumDelim"].Success ? match.Groups["ChecksumDelim"].Value : null;
            var accountNumber         = match.Groups["AccountNumber"].Success ? match.Groups["AccountNumber"].Value : null;
            var accountChecksum       = match.Groups["Checksum"].Success ? match.Groups["Checksum"].Value : null;
            var accountName           = match.Groups["AccountName"].Success ? match.Groups["AccountName"].Value : null;
            var payloadStartChar      = match.Groups["PayloadStartChar"].Success ? match.Groups["PayloadStartChar"].Value : null;
            var payloadEndChar        = match.Groups["PayloadEndChar"].Success ? match.Groups["PayloadEndChar"].Value : null;
            var payloadContent        = match.Groups["PayloadContent"].Success ? match.Groups["PayloadContent"].Value : null;
            var payloadPasswordDelim  = match.Groups["PayloadPasswordDelim"].Success ? match.Groups["PayloadPasswordDelim"].Value : null;
            var payloadPassword       = match.Groups["PayloadPassword"].Success ? match.Groups["PayloadPassword"].Value : null;
            var extendedChecksumDelim = match.Groups["ExtendedChecksumDelim"].Success ? match.Groups["ExtendedChecksumDelim"].Value : null;
            var extendedChecksum      = match.Groups["ExtendedChecksum"].Success ? match.Groups["ExtendedChecksum"].Value : null;

            // Check parsed completely
            if (epasaText != match.Value)
            {
                errorCode = EPasaErrorCode.BadFormat;
                return(false);
            }

            if (accountName != null)
            {
                // Account Name
                if (string.IsNullOrEmpty(accountName))
                {
                    errorCode = EPasaErrorCode.BadFormat;
                    return(false);
                }
                epasa.PayloadType = epasa.PayloadType | PayloadType.AddressedByName;
                epasa.AccountName = Pascal64Encoding.Unescape(accountName);
                epasa.Account     = epasa.AccountChecksum = null;
            }
            else
            {
                // Account Number
                if (!uint.TryParse(accountNumber, out var accNo))
                {
                    errorCode = EPasaErrorCode.InvalidAccountNumber;
                    return(false);
                }
                epasa.Account = accNo;
                var actualAccountChecksum = AccountHelper.CalculateAccountChecksum(accNo);

                if (checksumDelim != null)
                {
                    // validate account checksum
                    if (!uint.TryParse(accountChecksum, out var accChecksum))
                    {
                        errorCode = EPasaErrorCode.AccountChecksumInvalid;
                        return(false);
                    }
                    if (accChecksum != actualAccountChecksum)
                    {
                        errorCode = EPasaErrorCode.BadChecksum;
                        return(false);
                    }
                }
                epasa.AccountChecksum = actualAccountChecksum;
            }

            // Encryption type
            switch (payloadStartChar)
            {
            case null:
                break;

            case "[":
                if (payloadEndChar != "]")
                {
                    errorCode = EPasaErrorCode.MismatchedPayloadEncoding;
                    return(false);
                }
                epasa.PayloadType = epasa.PayloadType | PayloadType.Public;
                break;

            case "(":
                if (payloadEndChar != ")")
                {
                    errorCode = EPasaErrorCode.MismatchedPayloadEncoding;
                    return(false);
                }
                epasa.PayloadType = epasa.PayloadType | PayloadType.RecipientKeyEncrypted;
                break;

            case "<":
                if (payloadEndChar != ">")
                {
                    errorCode = EPasaErrorCode.MismatchedPayloadEncoding;
                    return(false);
                }
                epasa.PayloadType = epasa.PayloadType | PayloadType.SenderKeyEncrypted;
                break;

            case "{":
                if (payloadEndChar != "}")
                {
                    errorCode = EPasaErrorCode.MismatchedPayloadEncoding;
                    return(false);
                }
                epasa.PayloadType = epasa.PayloadType | PayloadType.PasswordEncrypted;
                break;

            default:
                throw new NotSupportedException($"Unrecognized start character '{payloadStartChar}'");
            }

            // Password
            if (epasa.PayloadType.HasFlag(PayloadType.PasswordEncrypted))
            {
                if (payloadPasswordDelim == null)
                {
                    errorCode = EPasaErrorCode.MissingPassword;
                    return(false);
                }
                epasa.Password = PascalAsciiEncoding.Unescape(payloadPassword ?? "");
            }
            else if (payloadPasswordDelim != null)
            {
                errorCode = EPasaErrorCode.UnusedPassword;
                return(false);
            }

            // Payload
            if (payloadStartChar != null)
            {
                if (payloadContent == null)
                {
                    epasa.Payload = string.Empty;
                }
                else if (payloadContent.StartsWith("\""))
                {
                    epasa.PayloadType = epasa.PayloadType | PayloadType.AsciiFormatted;
                    epasa.Payload     = PascalAsciiEncoding.Unescape(payloadContent.Trim('"'));
                }
                else if (payloadContent.StartsWith("0x"))
                {
                    epasa.PayloadType = epasa.PayloadType | PayloadType.HexFormatted;
                    epasa.Payload     = payloadContent.Substring(2);
                }
                else
                {
                    epasa.PayloadType = epasa.PayloadType | PayloadType.Base58Formatted;
                    epasa.Payload     = payloadContent;
                }
            }

            // Payload Lengths
            if (!EPasaHelper.IsValidPayloadLength(epasa.PayloadType, epasa.Payload))
            {
                errorCode = EPasaErrorCode.PayloadTooLarge;
                return(false);
            }

            // Extended Checksum
            var actualChecksum = EPasaHelper.ComputeExtendedChecksum(epasa.ToString(true));

            if (extendedChecksumDelim != null)
            {
                if (extendedChecksum != actualChecksum)
                {
                    errorCode = EPasaErrorCode.BadExtendedChecksum;
                    return(false);
                }
            }
            epasa.ExtendedChecksum = actualChecksum;



            return(true);
        }
        private EPasaErrorCode TryCompile(EPasaNode epasaNode, EPasa epasa)
        {
            EPasaErrorCode TryCompileAccount(AccountNode accountNode)
            {
                switch (accountNode.Type)
                {
                case TokenType.AccountName:
                    if (!Pascal64Encoding.IsValidEscaped(accountNode.Name.Value))
                    {
                        return(EPasaErrorCode.InvalidAccountName);
                    }
                    epasa.AccountName = Pascal64Encoding.Unescape(accountNode.Name.Value);
                    epasa.PayloadType = epasa.PayloadType.SetFlags(PayloadType.AddressedByName);
                    break;

                case TokenType.AccountNumber:
                    if (!uint.TryParse(accountNode.AccountNo.Value, out var accNo))
                    {
                        return(EPasaErrorCode.BadFormat);
                    }
                    if (accountNode.AccountNo.Value.StartsWith("0") && accNo != 0)
                    {
                        return(EPasaErrorCode.BadFormat);
                    }
                    epasa.Account = accNo;
                    var actualChecksum = AccountHelper.CalculateAccountChecksum(accNo);
                    if (accountNode.Checksum != null)
                    {
                        if (!uint.TryParse(accountNode.Checksum.Value, out var checksum))
                        {
                            return(EPasaErrorCode.BadFormat);
                        }
                        if (checksum != actualChecksum)
                        {
                            return(EPasaErrorCode.AccountChecksumInvalid);
                        }
                    }
                    epasa.AccountChecksum = actualChecksum;
                    break;

                default:
                    throw new ArgumentOutOfRangeException(nameof(accountNode));
                }
                return(EPasaErrorCode.Success);
            }

            EPasaErrorCode TryCompilePayload(PayloadNode payloadNode)
            {
                epasa.PayloadType = epasa.PayloadType | payloadNode.Encryption;
                if (payloadNode.Content != null)
                {
                    switch (payloadNode.Content.Type)
                    {
                    case TokenType.PascalAsciiString:
                        epasa.PayloadType = epasa.PayloadType | PayloadType.AsciiFormatted;
                        epasa.Payload     = PascalAsciiEncoding.Unescape(payloadNode.Content.Value);
                        break;

                    case TokenType.Base58String:
                        epasa.PayloadType = epasa.PayloadType | PayloadType.Base58Formatted;
                        epasa.Payload     = payloadNode.Content.Value;
                        break;

                    case TokenType.HexString:
                        epasa.PayloadType = epasa.PayloadType | PayloadType.HexFormatted;
                        epasa.Payload     = payloadNode.Content.Value;
                        break;

                    default:
                        throw new ArgumentOutOfRangeException(nameof(payloadNode.Content.Type));
                    }
                    if (!EPasaHelper.IsValidPayloadLength(epasa.PayloadType, epasa.Payload))
                    {
                        return(EPasaErrorCode.PayloadTooLarge);
                    }
                }
                if (payloadNode.Password != null)
                {
                    if (!EPasaHelper.IsValidPasswordLength(payloadNode.Password.Value))
                    {
                        return(EPasaErrorCode.InvalidPassword);
                    }
                    epasa.Password = PascalAsciiEncoding.Unescape(payloadNode.Password.Value);
                }
                return(EPasaErrorCode.Success);
            }

            EPasaErrorCode TryCompileExtendedChecksum(ValueNode extendedChecksumNode)
            {
                var actualExtendedChecksum = EPasaHelper.ComputeExtendedChecksum(epasa.ToString(true));

                if (extendedChecksumNode != null && extendedChecksumNode.Value != actualExtendedChecksum)
                {
                    return(EPasaErrorCode.AccountChecksumInvalid);
                }
                epasa.ExtendedChecksum = actualExtendedChecksum;
                return(EPasaErrorCode.Success);
            }

            var result = TryCompileAccount(epasaNode.Account);

            if (result != EPasaErrorCode.Success)
            {
                return(result);
            }
            if (epasaNode.Payload != null)
            {
                result = TryCompilePayload(epasaNode.Payload);
                if (result != EPasaErrorCode.Success)
                {
                    return(result);
                }
            }
            result = TryCompileExtendedChecksum(epasaNode.ExtendedChecksum);
            if (result != EPasaErrorCode.Success)
            {
                return(result);
            }

            return(result);
        }