4D v11 SQL Release 6 (11.6)
A
DDENDUM
Welcome to release 6 of 4D v11 SQL. This document presents the new features and modifications of this new version of the program.
Increased ciphering capacities
Release 6 of 4D v11 SQL extends the capacities of 4D applications as far as ciphering is concerned via two new features:
A new database parameter can be used to modify the cipher list used by 4D;
The GENERATE ENCRYPTION KEYPAIR command can be used to generate keys up to 2048 bits in length.
SET DATABASE
PARAMETER, Get
database parameter
A new selector (constant) is available for the SET DATABASE PARAMETER and Get database parameter commands.
Selector = 64 (SSL Cipher List) Values: String.
Description: This selector can be used to modify or get the cipher list
used by 4D for the SSL protocol. For example, you can use this selector to implement SSL 3.0 ciphering algorithms and thus refuse any connections in SSL 2.0. The cipher list is a sequence of strings separated by colons: "RC4-MD5:RC4-64-MD5:...."
4D v11 SQL Release 6 (11.6)
To reset the cipher list to its default value (stored permanently in the SLI file), call the SET DATABASE PARAMETER command and pass an empty string ("") in the value parameter.
By default, 4D uses the RC4 cipher algorithm. If you want to use the (more recent) AES algorithm, pass the following string in the value parameter: "AES:ALL:!aNULL:!eNULL:+RC4:@STRENGTH"
Note: With the Get database parameter command, the cipher list is returned
in the optional stringValue parameter and the return parameter is always 0.
` Configuration of 4D in SSL 3.0 only with refusal of SSL 2.0 connec-tions: C_TEXT($ssl3) $ssl3:="NULL-MD5:NULL-SHA:EXP-RC4-MD5:RC4-MD5:RC4-SHA: EXP-RC2-CBC-MD5:IDEA-CBC-SHA:EXP-DES-CBC-SHA:DES-CBC-SHA: DES-CBC3-SHA:EXP-EDH-DSS-DES-CBC-SHA:EDH-DSS-CBC-SHA:EDH- DSS-DES-CBC3-SHA:EXP-EDH-RSA-DES-CBC-SHA:EDH-RSA-DES-CBC-SHA:EDH-RSA-DES-CBC3-SHA:EXP-ADH-R"+"C4-MD5:ADH-RC4-MD5: EXP-ADH-DES-CBC-SHA:ADH-DES-CBC-SHA:ADH-DES-CBC3-SHA" SET DATABASE PARAMETER(SSL Cipher List;$ssl3)
GENERATE
ENCRYPTION
KEYPAIR
4D can now generate RSA keys with a length of 2048 bits using the GENERATE ENCRYPTION KEYPAIR command. To do this, you just need to pass the value 2048 in the length parameter.
Web Areas
WA Execute
JavaScript
Under Windows, the WA Execute JavaScript command now returns the result of the JavaScript code execution as it does under Mac OS.
Modification of logical mirror architecture
Beginning with release 6 of 4D v11 SQL, the mechanisms allowing the implementation of data backup solutions via a logical mirror have been modified. From now on, it is recommended to disable the current log file on the mirror machine. To do this, open the Preferences dialog box of the 4D Server mirror and display the
"Backup/Configuration" page. Uncheck the "Use Log File" option and confirm the operation by clicking on the Stop button in the warning dialog box that appears.
To allow the implementation of this principle, the INTEGRATE LOG FILE command can now be used without a current log file necessarily being activated.
This new principle allows you to avoid a potential risk of
desynchronization of the log files in the event of an incident, which became apparent in previous versions of 4D v11 SQL. If you have already implemented a logical mirror solution with 4D v11 SQL, we strongly recommend that you install release 6 on the server and mirror machines and that you modify your development in accordance with the scenario described below.
New operating
scenario
The typical scenario for implementing a backup system with a mirror is now the following (text in italics indicates steps that have been modified with respect to previous versions):
Step Operational machine Mirror machine 1 - Start up of the application.
- Back up of the data file.
- Activation (when necessary) of the log file. 4D creates the MyData-base.journal file.
- The application is exited.
- Copy of all the database files (log file included) onto the mirror
4D v11 SQL Release 6 (11.6)
2 - Restarting the application (verify that there is not a full backup pro-grammed).
- Beginning of operation.
- Start up of the mirror application. 4D Server requests the current log file: Select the MyDatabase.journal file that was transferred from the operational database.
- Disabling of the current log file on the Backup/Configuration page of the Preferences.
3 - Decision made to update the mir-ror (for example, after a certain period of operation).
- Execution of the method contai-ning the New log file command. The file saved is named MyData-base[0001-0000].journal.
- Sending of the MyDatabase[0001-0000].journal file via programming to the mirror machine (using 4DIC, Web Services, etc.).
- The database is operating.
4 - Detection of a file that is waiting to
be integrated.
- Execution of the method contai-ning the INTEGRATE LOG FILE command in order to integrate the MyDatabase[0001-0000].journal file.
5 - Incident occurs on the machine; the data file is unusable.
- Decision made to switch to the mirror machine.
- Copy of the current log file MyDa-tabase.journal onto the mirror machine, via the usual destination folder.
Opening preference (compatibility)
The new Allow opening v12 data file option found on the
"Database/Data Management" page of the Preferences can be used to set the future possibility of opening data files with 4D v11 SQL r6 that have been converted to version 12 (next major version of 4D):
This possibility meets two needs:
6 - Repair of the machine. - Detection of a file that is waiting to
be integrated. Execution of the method containing the INTEGRATE LOG FILE command in order to integrate the MyDatabase.journal file.
- As a precaution, creation of a current log file using the Backup/Configura-tion page of the Preferences.
- The database is operating.
7 - The machine is repaired.
- Replacement of the database files by those of the mirror database. - Start up of the application. 4D Ser-ver requests the log file: Select the file that was transferred from the mirror database.
- The database is exited. - Return to step 2.
4D v11 SQL Release 6 (11.6)
For security reasons, the No option is selected by default: opening a v12 data file will not be possible. You must explicitly authorize it via the Ask option (displays a confirmation dialog box) or the Yes option (direct opening).
Note : Only data files may remain compatible between two versions. A
structure file, once it has been converted into v12, can no longer be opened in v11.
