AS2Receiver Module

Properties Methods Events Configuration Settings Errors

The AS2Receiver component is used to process EDI messages and generate receipts.

Syntax

nsoftware.IPWorksEDI.As2receiver

Remarks

The AS2Receiver implements server-side processing of EDI messages, as specified in [AS2] and RFC 3335. It can be used to decrypt and verify incoming messages and to generate receipts including Message Disposition Notifications (MDNs). The class is designed to be easily incorporated into an HTTP server, and features custom functionality for server environments such as ASP.NET.

BASIC OPERATION

When an AS2 request comes in, you should first invoke ReadRequest. This will populate AS2From and AS2To, and based on this information, you may then set the appropriate certificates. You may specify your certificate with the Certificate property, and your trading partner's (signing) certificate with the SignerCert property.

Then, invoke ProcessRequest to process the request and generate the MDN receipt as specified in [AS2] and RFC 3335. If the request was processed successfully, EDIData will contain the transmitted EDI data. If a problem occurred, EDIData will not be populated and an exception will be thrown. In either case MDNReceipt will contain the RFC-compliant receipt, which should be returned to the client.

The MDNReceipt may be returned by invoking SendResponse. The receipt will be returned either synchronously in the HTTP reply, or asynchronously over a separate HTTP, HTTPS, or SMTP connection, as requested by the client.

To create log files, set LogDirectory prior to invoking ProcessRequest. This will log all incoming and outgoing data.

The following example illustrates how to use the class from an ASP.NET page. Note that in Java it will be necessary to provide an HTTPServletRequest as an argument to ReadRequest before processing the request.

EXAMPLE

AS2Receiver1.ReadRequest();
// At this point, you should check the values of AS2From and AS2To.
AS2Receiver1.Certificate = new Certificate(CertStoreTypes.cstPFXFile, "c:\\my_server_directory\\my_pfx_file.pfx", "my password", "CN=Me");
AS2Receiver1.SignerCert = new Certificate("c:\\my_server_directory\\my_partner_cer_file.cer");
AS2Receiver1.LogDirectory = "c:\\my_server_directory\\my_log_directory";
AS2Receiver1.ProcessRequest();
AS2Receiver1.SendResponse();

Additional functionality allows the user to examine details of the client's request, to permit certain types of errors, or to customize the outgoing MDN.

ADVANCED FUNCTIONALITY

Advanced functionality is provided to allow the user to break down the AS2 process, and to allow finer control over the operation of the server. Where ProcessRequest automates the entire process, additional methods are also provided to handle each step separately.

Parsing Incoming Data

To process an EDI message, invoke ReadRequest to process the headers from the server, or alternatively, manually set Request to the contents of the HTTP request. It may contain both headers and body, or the headers may be specified separately in RequestHeaders. This will provide more information about the client's request, without attempting to read the underlying EDI data.

After invoking ReadRequest, the AS2From, AS2To, and MessageId properties will contain the appropriate values. MDNTo will contain a nonempty string if an MDN is requested; RequestedSignatureProtocol, RequestedMICAlgorithms, and ReceiptDeliveryOption provide more information about the client's request. Finally, RequestHeaders contains the complete list of HTTP/AS2 headers.

Next, invoke ParseRequest. The certificate used to decrypt and sign should be specified with the Certificate property, and your partner's signing certificate should be specified with SignerCert. This will process the headers, decompress and/or decrypt the message (if applicable), and verify the signature (if present). EncryptionType, SignatureType, and CompressionFormat describe whether and how the data was encrypted, signed, and compressed, respectively.

ParseRequest will populate EDIType and Data.

Error Handling

If any errors occur an exception will be thrown and EDIData will not be populated. Information about the exception will be provided through the exception's error code and message and also through ScanResult. An MDN receipt reporting the error may still be generated; it is recommended that server software trap the error and invoke CreateMDNReceipt to report the error to the client.

The ErrorProcessingFlags property may be configured to allow predetermined types of errors. If ErrorProcessingFlags is set when ParseRequest (or ProcessRequest) is invoked, the errors specified will be allowed, an exception will not be thrown, and EDIData will still be determined. However, ScanResult will still report the error, as will the receipt generated by CreateMDNReceipt. To avoid reporting the errors in the receipt, set the ErrorReportingFlags property.

Creating an MDN-based Receipt

An MDN-based receipt may be created by invoking CreateMDNReceipt. Regardless of the success or failure of ProcessRequest, the receipt may be created as specified in RFCs 3335 and 2298. If no errors occurred when ProcessRequest was invoked, the receipt will report success and will be suitable for non-repudiation of receipt (NRR) if signed. If errors occurred, the MDN will report that an error occurred and that the EDI data was not processed. It is strongly recommended that server software trap any errors thrown by ProcessRequest and return the receipt in this case as well.

The MDNReceipt will consist of the MDN itself, a human-readable message, MIME headers and footers, and a signature if applicable. The receipt may be generated by invoking CreateMDNReceipt and customized further by setting the parameters to CreateMDNReceipt.

The Message parameter to CreateMDNReceipt may be used to customize the human-readable message in the receipt. If it is set to an empty string, an appropriate message will automatically be written whenever MDNReceipt is regenerated.

The receipt will be signed using the protocol specified by ReceiptSigningProtocol, if any. The certificate used to sign the receipt is specified by Certificate. By default the receipt will be signed if explicitly requested by the client, and unsigned otherwise.

Error reporting may be controlled by configuring ErrorReportingFlags. By default, any errors will cause MDNReceipt to report a failure to process the message (either "failed/Failure" or "processed/Error" will be reported, according to the specification and the type of error). Setting ErrorReportingFlags will cause the MDNReceipt to overlook the chosen types of errors. If all errors are overlooked, the MDNReceipt will report success and calculate a MIC on the original message as usual. A warning may be reported by setting the MDNWarning configuration setting.

Additional Server-Side Functionality

When used in a server environment such as ASP.NET, the class may be used to interface directly with the underlying HTTP context. If Request is not set by the user, ParseRequest and ProcessRequest will first get the request from the underlying HTTP environment, if possible. SendResponse will send the reply in this environment if able; otherwise the reply will be directed to standard out.

ASP.NET Core Notes

The class may be used within any .NET Standard compatible platform, including .NET Core and ASP.NET Core. When using AS2Receiver within an ASP.NET Core MVC application the class can be configured to automatically read from the request context, and send using the response context. To do so pass the HttpContext to the constructor of the AS2Receiver class. For instance:

//Inside HomeController.cs
As2receiver as2 = new As2receiver(HttpContext);

Property List

The following is the full list of the properties of the module with short descriptions. Click on the links for further details.


AS2From	The AS2 Identifier of the sending system.
AS2To	The AS2 Identifier of the receiving system.
Attachments	Collection of files attached to the current message.
CEMDetails	A collection of Certificate Exchange Messaging (CEM) details.
CertEncoded	The certificate (PEM/base64 encoded).
CertStore	The name of the certificate store for the client certificate.
CertStorePassword	If the certificate store is of a type that requires a password, this property is used to specify that password in order to open the certificate store.
CertStoreType	The type of certificate store for this certificate.
CertSubject	The subject of the certificate used for client authentication.
CompressionFormat	The compression format used on the incoming message.
EDIData	The EDI data sent in Request .
Firewall	A set of properties related to firewall access.
IncomingDirectory	The directory to be used to store incoming messages.
LocalHost	The name of the local host or user-assigned IP interface through which connections are initiated or accepted.
LogDirectory	The path to a directory for logging.
LogFile	The log file written.
MDNReceipt	The MDN-based receipt generated by the component.
MDNTo	The recipient for the Message Disposition Notification (MDN).
MessageId	The message ID of the incoming message.
ReceiptDeliveryOption	A URL indicating how the receipt is to be delivered.
Request	The HTTP request to be processed.
RequestHeaders	The HTTP headers in the AS2 request.
RequestHeadersString	The HTTP headers in the AS2 request.
RestartDirectory	The directory to log cached files when using AS2 restart functionality.
RolloverCertEncoded	The certificate (PEM/base64 encoded).
RolloverCertStore	The name of the certificate store for the client certificate.
RolloverCertStorePassword	If the certificate store is of a type that requires a password, this property is used to specify that password in order to open the certificate store.
RolloverCertStoreType	The type of certificate store for this certificate.
RolloverCertSubject	The subject of the certificate used for client authentication.
ScanResult	The result of invoking ParseRequest .
SignerCertEncoded	The certificate (PEM/base64 encoded).
SignerCertStore	The name of the certificate store for the client certificate.
SignerCertStorePassword	If the certificate store is of a type that requires a password, this property is used to specify that password in order to open the certificate store.
SignerCertStoreType	The type of certificate store for this certificate.
SignerCertSubject	The subject of the certificate used for client authentication.
SSLAcceptServerCertEncoded	The certificate (PEM/base64 encoded).
SSLAcceptServerCertStore	The name of the certificate store for the client certificate.
SSLAcceptServerCertStorePassword	If the certificate store is of a type that requires a password, this property is used to specify that password in order to open the certificate store.
SSLAcceptServerCertStoreType	The type of certificate store for this certificate.
SSLAcceptServerCertSubject	The subject of the certificate used for client authentication.
SSLCertEncoded	The certificate (PEM/base64 encoded).
SSLCertStore	The name of the certificate store for the client certificate.
SSLCertStorePassword	If the certificate store is of a type that requires a password, this property is used to specify that password in order to open the certificate store.
SSLCertStoreType	The type of certificate store for this certificate.
SSLCertSubject	The subject of the certificate used for client authentication.
UsePSS	Whether to use RSA-PSS during signing and verification.

Method List

The following is the full list of the methods of the module with short descriptions. Click on the links for further details.


AckRequest	Optional. Acknowledges the incoming request.
Config	Sets or retrieves a configuration setting.
CreateMDNReceipt	Creates MDNReceipt .
ParseRequest	Parses the EDI message and determines the EDIData .
ProcessRequest	Processes the EDI data, and generates the receipt.
ProcessRestartRequest	Processes the AS2 restart request, and sends a response to the client.
ReadRequest	Reads the AS2 request from the HTTP session.
Reset	Resets the state of the control.
SendAsyncMDN	Sends the MDNReceipt to the RemoteURL specified.
SendResponse	In a server environment, responds to the requesting client with MDNReceipt .
SetTPInfo	A convenient way to set AS2 communication parameters using XML strings.

Event List

The following is the full list of the events fired by the module with short descriptions. Click on the links for further details.


CEMRequest	Fired when a Certificate Exchange Messaging (CEM) request is received.
CEMResponse	Fired when a Certificate Exchange Messaging (CEM) response is received.
EDIDataInfo	Fired when processing an incoming message.
Error	Information about errors during data delivery.
Log	Fired with log information while processing a message.
RecipientInfo	Fired for each recipient certificate of the encrypted message.
SignerCertInfo	Fired during verification of the signed message.
SSLServerAuthentication	For asynchronous HTTPS MDNs, fired after the server presents its certificate.
SSLStatus	Shows the progress of the secure connection.

Configuration Settings

The following is a list of configuration settings for the module with short descriptions. Click on the links for further details.


AcceptAnySignerCert	Used to accept trust any signing certificate unconditionally.
AS2VersionIncoming	The version of AS2 that was used in the incoming message.
AS2VersionOutgoing	The version of AS2 to be used in the outgoing message.
Authorization	The Authorization string to be sent to the server.
AuthScheme	The authorization scheme to be used when server authorization is to be performed.
CEMCertDir	Specifies the directory where certificates are saved when receiving a CEM request.
CloseStreamAfterProcessing	Specifies whether or not the OutputStream should be closed after processing.
DecodeTempDirectory	The temp directory the component will use to decode messages.
DetectDuplicates	Whether to detect duplicate messages.
EncryptionAlgorithm	The encryption algorithm used to encrypt the incoming data.
EncryptionPaddingScheme	The encryption padding scheme used when encrypting the incoming data.
EncryptionType	The MIME type of the encrypted data.
ErrorProcessingFlags	Flags controlling how errors affect ProcessRequest.
ErrorReportingFlags	Flags controlling how errors affect the MDNReceipt.
FilenameSource	The location from which to read the filename.
InvalidFilenameMDNAction	Instructs MDN disposition on invalid and duplicate filenames.
LogDebug	Whether to log debug data.
LogFilename	The base name of the log file.
LogOptions	The information to be written to log files.
MaxParts	The maximum number of MIME parts to process.
MDNDisposition	Overrides the automatically calculated MDN disposition.
MDNMICAlgorithm	The algorithm used to sign the outgoing MDN.
MDNReportingUA	The name of the user agent performing the disposition.
MDNSendingMode	The level of end user interaction involved in sending the MDN.
MDNWarning	A warning to appear in the MDN.
NormalizeMIC	Whether to normalize line endings before calculating the MIC.
OverwriteCEMCerts	Whether existing CEM certificates are overwritten when a duplicate is received.
Password	A password if authentication is to be used.
ProcessingError	A processing error occurred in the received EDI message.
ProxyAuthorization	The authorization string to be sent to the proxy server.
ProxyPassword	A password if Basic authentication is to be used for the proxy.
ProxyPort	Port for the proxy server (default 80).
ProxyServer	Name or IP address of a proxy server (optional).
ProxyUser	A user name if Basic authentication is to be used for the proxy.
ReceiptSigningProtocol	The protocol used to sign the outgoing MDN receipt.
RequestedMICAlgorithms	The Message Integrity Check algorithm(s) requested by the client, if any.
RequestedSignatureProtocol	The signing protocol requested by the client, if any.
RequestFile	Reads the AS2 message from disk.
RequireAS2To	Ensure that the received message is intended for the given AS2 identifier.
RequiredSignatureAlgorithms	Specifies a list of acceptable signature algorithms.
RequireEncrypt	Ensure that the received message is encrypted.
RequireOAEP	Ensure that the encryption padding mode is RSAES-OAEP.
RequirePSS	Ensure that the signature scheme in the received message is RSASSA-PSS.
RequireSign	Ensure that the received message is signed.
ResponseSubject	The subject to be used for the MDN response.
SenderSignatureAlgorithm	The algorithm used by the sender to sign the message.
SenderSignatureScheme	The signature scheme used by the sender to sign the message.
SignatureType	The MIME type of the signature (if any).
SignerCACert	CA certificate used to verify signed messages.
SMTPFrom	The email address of the sender of the message.
SMTPServer	The SMTP server to be used.
User	A user name if authentication is to be used.
WarnOnMDNFailure	Whether to log a .wrn file instead of a .err file when MDN delivery fails.
AcceptEncoding	Used to tell the server which types of content encodings the client supports.
AllowHTTPCompression	This property enables HTTP compression for receiving data.
AllowHTTPFallback	Whether HTTP/2 connections are permitted to fallback to HTTP/1.1.
Append	Whether to append data to LocalFile.
Authorization	The Authorization string to be sent to the server.
BytesTransferred	Contains the number of bytes transferred in the response data.
ChunkSize	Specifies the chunk size in bytes when using chunked encoding.
CompressHTTPRequest	Set to true to compress the body of a PUT or POST request.
EncodeURL	If set to true the URL will be encoded by the component.
FollowRedirects	Determines what happens when the server issues a redirect.
GetOn302Redirect	If set to true the component will perform a GET on the new location.
HTTP2HeadersWithoutIndexing	HTTP2 headers that should not update the dynamic header table with incremental indexing.
HTTPVersion	The version of HTTP used by the component.
IfModifiedSince	A date determining the maximum age of the desired document.
KeepAlive	Determines whether the HTTP connection is closed after completion of the request.
KerberosSPN	The Service Principal Name for the Kerberos Domain Controller.
LogLevel	The level of detail that is logged.
MaxRedirectAttempts	Limits the number of redirects that are followed in a request.
NegotiatedHTTPVersion	The negotiated HTTP version.
OtherHeaders	Other headers as determined by the user (optional).
ProxyAuthorization	The authorization string to be sent to the proxy server.
ProxyAuthScheme	The authorization scheme to be used for the proxy.
ProxyPassword	A password if authentication is to be used for the proxy.
ProxyPort	Port for the proxy server (default 80).
ProxyServer	Name or IP address of a proxy server (optional).
ProxyUser	A user name if authentication is to be used for the proxy.
SentHeaders	The full set of headers as sent by the client.
StatusLine	The first line of the last response from the server.
TransferredData	The contents of the last response from the server.
TransferredDataLimit	The maximum number of incoming bytes to be stored by the component.
TransferredHeaders	The full set of headers as received from the server.
TransferredRequest	The full request as sent by the client.
UseChunkedEncoding	Enables or Disables HTTP chunked encoding for transfers.
UseIDNs	Whether to encode hostnames to internationalized domain names.
UserAgent	Information about the user agent (browser).
ConnectionTimeout	Sets a separate timeout value for establishing a connection.
FirewallAutoDetect	Tells the component whether or not to automatically detect and use firewall system settings, if available.
FirewallHost	Name or IP address of firewall (optional).
FirewallPassword	Password to be used if authentication is to be used when connecting through the firewall.
FirewallPort	The TCP port for the FirewallHost;.
FirewallType	Determines the type of firewall to connect through.
FirewallUser	A user name if authentication is to be used connecting through a firewall.
KeepAliveInterval	The retry interval, in milliseconds, to be used when a TCP keep-alive packet is sent and no response is received.
KeepAliveTime	The inactivity time in milliseconds before a TCP keep-alive packet is sent.
Linger	When set to True, connections are terminated gracefully.
LingerTime	Time in seconds to have the connection linger.
LocalHost	The name of the local host through which connections are initiated or accepted.
LocalPort	The port in the local host where the component binds.
MaxLineLength	The maximum amount of data to accumulate when no EOL is found.
MaxTransferRate	The transfer rate limit in bytes per second.
ProxyExceptionsList	A semicolon separated list of hosts and IPs to bypass when using a proxy.
TCPKeepAlive	Determines whether or not the keep alive socket option is enabled.
TcpNoDelay	Whether or not to delay when sending packets.
UseIPv6	Whether to use IPv6.
LogSSLPackets	Controls whether SSL packets are logged when using the internal security API.
OpenSSLCADir	The path to a directory containing CA certificates.
OpenSSLCAFile	Name of the file containing the list of CA's trusted by your application.
OpenSSLCipherList	A string that controls the ciphers to be used by SSL.
OpenSSLPrngSeedData	The data to seed the pseudo random number generator (PRNG).
ReuseSSLSession	Determines if the SSL session is reused.
SSLCACerts	A newline separated list of CA certificate to use during SSL client authentication.
SSLCheckCRL	Whether to check the Certificate Revocation List for the server certificate.
SSLCipherStrength	The minimum cipher strength used for bulk encryption.
SSLEnabledCipherSuites	The cipher suite to be used in an SSL negotiation.
SSLEnabledProtocols	Used to enable/disable the supported security protocols.
SSLEnableRenegotiation	Whether the renegotiation_info SSL extension is supported.
SSLIncludeCertChain	Whether the entire certificate chain is included in the SSLServerAuthentication event.
SSLNegotiatedCipher	Returns the negotiated ciphersuite.
SSLNegotiatedCipherStrength	Returns the negotiated ciphersuite strength.
SSLNegotiatedCipherSuite	Returns the negotiated ciphersuite.
SSLNegotiatedKeyExchange	Returns the negotiated key exchange algorithm.
SSLNegotiatedKeyExchangeStrength	Returns the negotiated key exchange algorithm strength.
SSLNegotiatedVersion	Returns the negotiated protocol version.
SSLProvider	The name of the security provider to use.
SSLSecurityFlags	Flags that control certificate verification.
SSLServerCACerts	A newline separated list of CA certificate to use during SSL server certificate validation.
TLS12SignatureAlgorithms	Defines the allowed TLS 1.2 signature algorithms when UseInternalSecurityAPI is True.
TLS12SupportedGroups	The supported groups for ECC.
TLS13KeyShareGroups	The groups for which to pregenerate key shares.
TLS13SignatureAlgorithms	The allowed certificate signature algorithms.
TLS13SupportedGroups	The supported groups for (EC)DHE key exchange.
AbsoluteTimeout	Determines whether timeouts are inactivity timeouts or absolute timeouts.
FirewallData	Used to send extra data to the firewall.
InBufferSize	The size in bytes of the incoming queue of the socket.
OutBufferSize	The size in bytes of the outgoing queue of the socket.
BuildInfo	Information about the product's build.
CodePage	The system code page used for Unicode to Multibyte translations.
LicenseInfo	Information about the current license.
UseInternalSecurityAPI	Tells the component whether or not to use the system security libraries or an internal implementation.