PI63041: WHEN FTP CLIENT OR SERVER SECURED WITH ATTLS FAILS WITH ERROR 451 TRANSFER ABORTED DUE TO FILE ERROR.

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• zOS FTP client or server configured to be secure using attls
  (TLSMECHANISM ATTLS) can a fail with error '451 Transfer aborted
  due to file error'. The error only occurs when the zOS FTP
  client is receiving data from a secure server ; ie GET, or when
  the zOS FTP server is receiving data from an FTP client, ex
  client issued a PUT. The situation occurs when the sender of the
  file, sends an SSL secure shutdown (close alert) and does not
  send a FIN, but instead sends a reset on the FTP data
  connection.
  This error does not occur when the FTP client or server are
  secured using native SSL (TLSMECHANISM FTP).
  

Local fix

• use FTP with native SSL (TLSMECHANISM FTP) or correct sender of
  data to insure FIN is sent
  

Problem summary

• ****************************************************************
  * USERS AFFECTED: All users of the IBM Communications Server   *
  *                 for z/OS Version 1 Release 13 IP: FTP        *
  ****************************************************************
  * PROBLEM DESCRIPTION: An FTP data connection secured by ATTLS *
  *                      is transferring data inbound and at the *
  *                      end of the transfer is receiving        *
  *                      'EZA2590E recv error from receive_data  *
  *                      - EDC8121I Connection reset. . .        *
  *                      (errno2=0x74520442)' or '451 Transfer   *
  *                      aborted due to receive error'.          *
  ****************************************************************
  * RECOMMENDATION: Apply PTF.                                   *
  ****************************************************************
  The problem can be summarized as follows:
  1. During the termination of the FTP data connection, the
  remote peer sends an SSL Close Notify alert.
  2. The local side will send a SSL Close Notify alert in
  response.
  3. The remote peer in response sends a RST without an
  intermediate FIN causing a error to be reported to the
  application.
  +-------------------------------------------------------------+
  + Please check our Communications Server for OS/390 homepages +
  + for common networking tips and fixes.  The URL for these    +
  + homepages can be found in Informational APAR II11334.       +
  +-------------------------------------------------------------+
  

Problem conclusion

• FTP code is updated to indicate a FTP data connection
  secured by ATTLS in order to allow RST arriving after
  the SSL Close_Notify alert to be ignored.
  
  * Cross Reference between External and Internal Names
  

Temporary fix

Comments

APAR Information

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

  PI62054

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

  UI39801

Modules/Macros

• EZAFTPFU EZBPFIOC EZBTCFRD EZBTCRD  EZBTLFIO
  EZBZTLSC EZBZTLSP EZBZTLSX EZB2TLSX
  

Fix information

• Fixed component name

  TCP/IP V3 MVS

• Fixed component ID

  5655HAL00

Applicable component levels

• R1D0 PSY UI39801

     UP16/09/17 P F609

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.