7th March 2017 - New versions of Mail Queue
Component and IP Log Streaming Component, lots of SSL improvements
This page contains various components written by Magenta Systems Ltd to extend the François Piette's Internet Component Suite (ICS) version 8 from http://www.overbyte.be/. ICS v8 supports Delphi 7, 2006 to 2010, XE to XE8, 10 Seattle, 10.1 Berlin and 10.2 Tokyo. Note that all ICS versions now include SSL free of charge.
The latest versions of ICS may be downloaded from the ICS SubVersion server using a subversion client such as TortoiseSVN. Once your SVN client is installed, you can browse to svn://svn.overbyte.be/ics, svn://svn.magsys.co.uk/ics or http://svn.overbyte.be:8443/svn/ics or http://svn.magsys.co.uk:8443/svn/ics. The SVN login user code is ics and password is ics for read access.
Internet Component Suite (ICS) Downloads
All ICS files should normally be accessed from the ICS Download Wiki page but the important files are available here as well.
Please note older versions of the ICS source code had an internal check to only allow loading of the latest OpenSSL it was tested with, so you could not use new DLLs with an old application without recompiling with the latest version of ICS first. But ICS V8 versions later than 25th March 2015 relax this check so that minor versions with a letter suffix that don't add new features or break anything (in theory) are now supported. This worked for about a year, but OpenSSL 1.0.2g and 1.0.1s, and later, no longer generally support SSLv2 which means old versions of ICS can no longer load them, so V8.24 dated 3rd March 2016 or later is now needed for these current and newer OpenSSL releases. ICS V8.31 supports up to 1.0.2z, and ICS V8.32 up to 1.1.0z. Also note ICS V8 no longer supports 1.0.x and earlier.
OpenSSL 1.0.1 and later are only supported by ICS v8, v7 is no longer updated for new OpenSSL versions. The 64-bit DLLs are only for use with Delphi applications compiled for the 64-bit platform, the 32-bit DLLs work on both 32-bit and 64-bit Windows with 32-bit applications. Note that ICS V8.24 dated 3rd March 2016 and later now include the latest OpenSSL 1.0.2 Win32 files to avoid a separate download.
OpenSSL 1.1.0 is a major new version with new DLL file names and many different exports, and requires ICS V8.33 dated 29th August 2016, or later. Generally, applications need not be changed, but there are several new SSL features in V8.33 that should be studied. Beware the OpenSSL 1.1.0 DLLs may not be used with any existing SSL applications until they have been specifically updated to support all the changes.
OpenSSL 1.1.1 is currently alpha testing with final release due no earlier than May 2018, and is not recommended for production machines. It adds support for TLSv1.3 draft 23 and various new cryptographic private key and hash digest types. Delphi applications require a version of ICS dated after the OpenSSL release (each needs to be tested for compability), usually the nightly zip which is currently V8.52.
The OpenSSL DLLs and EXE files included in the zips above are digitally code signed 'Open Source Developer, François PIETTE', the lead developer for ICS. The Magenta Systems Code Signing Trust and Certificate Check component may be used to check the correctly signed DLLs are being used by ICS, with this functionality included in ICS V8.38 and later.
Magenta Systems Mail Queue Component
Magenta Systems Mail Queue Component has two main benefits over a simple TSslSmtpCli component: it supports extended retries over many hours or days, and supports multiple SMTP relay servers or looks-up MX servers, while alleviating the need for the application to handle retries. The component also allows HTML mail to be sent using SSL, something THtmlSmtpCli does not currently support. Mail is queued to disk, so retries will continue if the application is restarted.
TMagMailQueue is designed to prepare, queue and send email. Preparing the email is done using the the ICS THtmlSmtpCli component so it may be plain text or HTML email with one or more file attachments.
Once the mail properties in QuHtmlSmtp have been specified, it is queued using the QueueMail method which saves it to an EML spool file.
The component runs a thread which checks the queue for new EML spool files, and attempts to forward them to one or more SMTP Mail Servers using TSslSmtpCli, optionally with SSL. If mail delivery succeeds, the spool file may be deleted or moved to an archive folder. If mail delivery fails, the spool file remains in the queue and further attempts are made separated by the times in minutes listed in the RetryList list. If all delivery attempts fail, the spool file may be deleted or moved to a badmail folder.
Note that some email servers support grey listing and reject the first email attempt from a new sender but allow a retry 10 or 15 minutes later, something that is very effective in blocking spam emails (since they don't usually retry).
If multiple mail servers are specified, delivery is attempted once using each server, for each retry attempt. Each mail server is specified as TMailServer and there is no limit to the total.
Each time the queue is updated or a delivery attempt made, the queue is saved to file in the control folder, so the component may be stopped and restarted with failed attempts continuing.
The EML spool files are compatible with those created by many Microsoft email applications such as CDO, and the AddtoQueue method can also be used to queue existing EML files with the queue details specified in MailQuItem.
Note, this component is intended for sending low volume email from individual Delphi applications, with more flexibility than a simple TSslSmtpCli component. For use as a heavy duty SMTP server, queue processing could be improved to avoid moving records around as much or saving them to disk as often, and mail bodies could be read as required from disk instead of being read entirely to memory first. A mail pickup folder could be added which is scanned for new EML files.
Files and Folders Used
The TMagMailQueue component heavily uses disk files, in different sub-directories within the mail root directory specified in property MailQuDir, these are:
If logging of sent email is specified, the default file name FileQuSent property is MailQuSent-yyyymmdd.log inb CSV format similar to MailQuItems.Hdr.
A demo application mailqudemo.exe illustrates simple email queuing. The zip contains the EXE demo and required SSL files.
18th January 2011 - 1.0 - first public release. Not yet tested with Delphi 2009 or later.
2nd March 2011 - 1.2 - automatically create mailqueue directory in demo application, removed missing uses statement. Support queuing mail with OwnHeaders bypassing htmlmail. Log event definition changed.
11th August 2011 - 1.2 - updates subroutines for Win64 support, removed one unneeded unit from uses.
5th Oct 2011 - 1.3 - Debug logging works properly Don't retry emails that fail too large for server (error 552)
11th Sept 2012 - 1.4 - ICS V8, IPv6
23rd March 2013 - 1.5 - Added Mail Server SocketFamily and LocalAddr6 for IPv6
10th Dec 2014 - 1.6 - Better SSL handshake reporting
27th Oct 2015 - 2.0 - requires ICS V8.19 October 2015 or later.
7th July 2016 - 2.1 - requires ICS V8.30 July 2016 or later.
1st December 2016 - 2.2 - requires ICS V8.39 November 2016 or later.
6th March 2017 - 2.3 - requires ICS V8.43 March 2017 or later.
Magenta Systems IP Log Streaming Component
A demo application testiplog.exe illustrates use of TMagIpLog as a TCP or UDP client or server, and both in the same program sending data locally.
The same component may be used in a client or server application, to send or receive.
1 - Drop the component onto a form (or create it in code, see testiplog.exe).
2 - Specify LogProtocol as one of logprotUdpClient, logprotUdpServer, logprotTcpServer, logprotTcpClient.
3 - For client protocols, specify RemoteHost (name or IP address) and RemoteIpPort, CheckPing true if ping to be used, RetryAttempts to non-zero if continual retries not needed, RetryWaitSecs for delay between retries .
4 - For server protocols, LocalIpAddress is 0.0.0.0 to listen on all local addresses, LocalIpPort must be non-zero.
5 - For sending data, AddCRLF to false if line already have terminating characters, UdpNoCRLF to false if UDP should send CRLF.
6 - For receiving data, LineEndType to one of lineendCR, lineendLF, lineendCustom (set in hex in CustomLineEnd) or lineendPacket (for UDP), then MaxLineLen if a line should be returned before lineend is found, normally non-ASCII characters are removed, set StripControls to false if they should be replaced by spaces, RawData to true if CR, LF, FF and control characters should not be removed.
7 - Assign onLogRecvEvent if data is to be received, onLogChangeEvent if tracking of start and stop is needed, onLogProgEvent if progress information is needed for logging.
8 - Call StartLogging. The LogChangeEvent and LogProgEvent will trigger when LogState changes to logstateOK when data may be sent.
9 - To send a line, if function GetAnyStateOK is true, call SendLogLine. MaxSendBuffer specifies the amount of data that can be buffered otherwise SendLogLine will fail.
10 - Received data will trigger LogRecvEvent once per line.
11 - Call StopLogging to stop. Buffered data may continue to be sent after close, keep calling CheckStopped until true when it's really finished and component may be destroyed.
12 - To send an unlimited size stream, create a stream in the application with TBufferedFileStream or TFileStream, and pass it to SendStream. LogState changes to logstateOKStream while it's being sent, then back to logstateOK as it finishes, the application should then free the stream.
13 - There is no specific handling for receiving a stream, textual data will be handled according to the normal line end properties, and can be saved to another stream in LogRecvEvent. Binary data is more problematic, set RawData to true and MaxLineLen to get a buffer load at a time, but the last buffer load will need to be extracted with GetPartialLine using a timeout, this is called automatically when the connection is closed.
14 - To send to multiple clients, set MaxSockets to the number needed, then use the function SetRemotes to specify the remote host and port for each socket number, base 0. The events all return Socnr to indicate which socket. MaxSockets also specifies how many remote clients can connect to TCP Server, but note that Socnr is dynamic and changes as remote clients come and go.
15 - To support SSL on TCP/IP client or server, drop an TSslContext component on the form, assign it to the LogSslContext property and set the ForceSsl property to true. For better performance, set LogSslSessCache to a TSslAvlSessionCache component.
16 - For SSL TCP Server, the SslContext component must have the SslCertFile and SslPrivKeyFile properties set to the file names of an SSL certificate and Private Key PEM files respectively, and SslCipherList set to sCipherMozillaSrvBack for strong but backward compatiblle cipher support. The component includes sample self signed certificate and password files iplog-cert.pem and iplog-prvkey.pem, and you can create your own with the ICS SSL sample application Pemtool, or buy commercial PEM certificates.
17 - For SSL TCP Client, the SslContext component must have the SslCAFile property set to the file name of a PEM root certification authority file containing trusted root certificates. Such a file is supplied with the component RootCaCertsBundle.pem containing various root certificates covering most major registries. SslContext SslCipherList can be left as the default to allow connection to any server. The LogSslVerMethod property can be logSslVerNone to skip certificate verification, logSslVerBundle to check using the CA bundle file or logSslVerWinStore to check using the Windows certificate store (a little slower, bur maybe more certificates). To check if certificates have been revoked set LogSslRevocation to true, beware this needs public internet access and can be very slow or fail. LogSslReportChain set to true reports certificate details checked.
18th August 2007 - 1.1 - using OverbyteIcsFtpSrvT instead of OverbyteIcsLibrary, UDP receive packets may be from multiple hosts, always keep IP.
5th August 2008 - 1.2 - made compatible with ICS V7 and Delphi 2009. Note only supports ANSI with Delphi 2009.
20th August 2009 - 1.3 - fixed problem with MaxSockets being reported as closed in the event when only one was open, tested with Delphi 2010.
9th August 2010 - 1.4 - removed cast warnings with Delphi 2009 and later
22nd Sept 2011 - 1.5 - added SndBufSize and RcvBufSize to increase buffer sizes and speed
11th Sept 2012 - 1.6 - better error for too many clients with server added CurSockets property for current number of server sockets
7th July 2014 - 2.0 - now only ICS 8 and later, using new ICS ping.
13th July 2015 - 2.2 - requires ICS V8.18 June 2015 or later.
23rd Oct 2015 - 2.3 - requires ICS V8.19 October 2015 or later.
8th July 2016 - 2.4 - requires ICS V8.30 July 2016 or later.
23rd Nov 2016 - 2.5 - requires ICS V8.39 November 2016 or later.
7th March 2017 - 2.6 - requires ICS V8.43 March 2017 or later.
Threaded Ping Component and Trace Route Demo
A threaded version of Ping to avoid applications becoming non-responsive while pinging. Note the application needs to use a TThread OnTerminate event in which to retrieve the Reply results of the ping. The component will optionally look-up the host name of the computer that was pinged. Also includes a UDP echo component. A demo application illustrates use of the threaded ping to perform multiple pings at the same time. It also illustrates how to write a Trace Route application. Supports ICS v7.
NOTE - this component is no longer supported, ICS v8 now includes threaded ping and a trace route demo.
Whois Component and Demo
A Whois component and demonstration application. Whois is a protocol to interpret a remote server for information about a domain name or an IP address, and return textual information about 'owner' of the name or address. The demo application interprets the result and will perform a secondary query to another Whois server if necessary.
SNTP Time Server and Client Components
TTimeServ is an updated version of Nathan Anderson's time server component adding SNTP support. TWSTimeClient is an updated version of Chris Barber's time client component adding SNTP support and functions to change the PC UTC time. SNTP provides time correction with fractional seconds, unlike the earlier Time protocol that is round seconds only.
Magenta Systems Ltd, 9 Vincent Road,
Croydon CR0 6ED, United Kingdom