PH62134: FOR MQ (Z/OS) ALLOW CHLAUTH RECORDS TO BE CHECKED WITH USERID CASE INSENSITIVITY

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• Development finds, currently for z/OS MQ, the case of users
  specified in CHLAUTH rules are significant so that userids of
  different case are treated distinctly (e.g. a rule specifying a
  userid of 'MQ' would not block 'Mq' or 'mq'. This is working
  correctly. However, previously distributed MQ implemented
  mechanisms to ignore the case of the userid when checking
  CHLAUTH rules. This code change does not currently have any
  effect on z/OS because the affected code is not checking its
  value when performing the comparisons.
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED: All users of IBM MQ for z/OS Version 9       *
  *                 Release 2 Modification 0,                    *
  *                 Release 3 Modification 0 and                 *
  *                 Release 4 Modification 0.                    *
  ****************************************************************
  * PROBLEM DESCRIPTION: When setting CHLAUTH rules, such as     *
  *                      SET CHLAUTH(<channel>) TYPE(BLOCKUSER)  *
  *                      USERLIST(<userid>), it can be           *
  *                      useful for users to disable case        *
  *                      sensitivity for user IDs, which is the  *
  *                      current default behaviour. This feature *
  *                      had been introduced on distributed      *
  *                      platforms through a tuning              *
  *                      parameter but was not enabled for Z.    *
  ****************************************************************
  The code which matches the user IDs from the CHLAUTH's BLOCKUSER
  list with the user ID trying to connect to the channel is always
  case sensitive on Z. On distributed platforms, a tuning
  parameter can set this function to disable or enable
  the case sensitivity flag when matching the strings, while on Z,
  this flag is set to FALSE (disabled).
  

Problem conclusion

• The code has been changed to reflect the value of the QMGR's
  tuning parameter when comparing the BLOCKUSER list and the user
  accessing the channel instead of a FALSE set value. As a result,
  case sensitivity for CHLAUTH records can be disabled with the
  ChlAuthIgnUsrCase tuning parameter.
  

Temporary fix

Comments

APAR Information

• APAR is sysrouted FROM one or more of the following:

• APAR is sysrouted TO one or more of the following:

  UI98242 UI98243 UI98244

Modules/Macros

• CMQXRSCF
  

Fix information

• Fixed component name

  IBM MQ Z/OS V9

• Fixed component ID

  5655MQ900

Applicable component levels

• R200 PSY UI98244

     UP24/09/25 P F409

• R300 PSY UI98243

     UP24/09/25 P F409

• R400 PSY UI98242

     UP24/09/25 P F409

Fix is available

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