PH34373: USER TRYING TO LOG INTO CICS, AN IPV4 ADDRESS WAS FORMATTED AS IPV6 ADDRESS, AND AN INVALID IPV6 FORMAT WAS CREATED

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• The regular users are logging in CICS via a 3270 emulator,
  sometimes, you see the following two problems,
  .
  1) The actual IP address of the terminal is an IPV4 address,
  CICS is trying to make an IPV6 out of it.
  2) The IPV6 created has an invalid format, in this case
  it should have been 0::FFFF:aaa:bbbb and not aaa:bbbb::0
  .
  This problem doesn't happen frequently and but when it does, the
  user is not allowed into the CICS region which is a problem for
  customer.
  .
  The problem appears to be caused by the value in
  TCTE_TPADDR_TYPE,
  - This should be a x'04' for a normal IPv4 address.
  - If the value is not x'04'then it will cause the IP address to
    be formatted as an IPv6 address, which is exactly what is
    being observed.
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED: All CICS users.                              *
  ****************************************************************
  * PROBLEM DESCRIPTION: CICS formats IP addresses incorrectly.  *
  ****************************************************************
  The CICS / VTAM Logon Exit DFHZLGX does not
  set field TCTE_TPADDR_TYPE correctly.
  CICS subsequently uses the contents of TCTE_TPADDR_TYPE
  to control the formatting of IP addresses.
  When CICS formats TN3270 IPV4 addresses it incorrectly
  formats them as IPV6 addresses.
  This results in incorrect output when executing
  EXEC CICS INQUIRE ASSOCIATION CLIENTIPADDR()
  and incorrectly formatted IP addresses in SMF data.
  Additional Keywords: 3270
  

Problem conclusion

• The CICS / VTAM Logon Exit DFHZLGX has been modified to
  set field TCTE_TPADDR_TYPE correctly.
  

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:

  UI74973 UI74974 UI74975

Modules/Macros

• DFHZLGX
  

Fix information

• Fixed component name

  CICS TS Z/OS V5

• Fixed component ID

  5655Y0400

Applicable component levels

• R100 PSY UI74975

     UP21/04/20 P F104

• R200 PSY UI74974

     UP21/04/20 P F104

• R300 PSY UI74973

     UP21/04/20 P F104

Fix is available

• Select the PTF appropriate for your component level. You will be required to sign in. Distribution on physical media is not available in all countries.