WAPPC32 Ignores User ID Provided By APPC App On Consecutive Allocate Requests

ID: Q218165

The information in this article applies to:

Microsoft SNA Server, versions 3.0SP3, 4.0, 4.0SP1, 4.0SP2

SYMPTOMS

If the host supports LU6.2 persistent verification or already verified security, and an APPC application calls TP_STARTED once, followed by multiple [MC_]ALLOCATE requests for consecutive conversations, the User ID provided in subsequent [MC_]ALLOCATE requests may be ignored, causing the persistent verification session to be used.

However, if the APPC application issues a new TP_STARTED for every [MC_]ALLOCATE request, this problem does not occur.

CAUSE

The Wappc32.dll file was failing to clear the user_id field on subsequent allocation requests (where security=AP_SAME) made over an LU6.2 session that supports persistent verification or already verified security.

RESOLUTION

SNA Server 4.0

To resolve this problem, obtain the latest service pack for SNA Server version 4.0. For additional information, please see the following article in the Microsoft Knowledge Base:

Q215838 How to Obtain the Latest SNA Server Version 4.0 Service Pack

SNA Server 3.0

To resolve this problem, obtain the latest service pack for SNA Server version 3.0. For additional information, please see the following article in the Microsoft Knowledge Base:

Q184307 How to Obtain the Latest SNA Server Version 3.0 Service Pack

STATUS

Microsoft has confirmed this to be a problem in SNA Server versions 3.0 and 4.0. This problem was first corrected in SNA Server version 3.0 Service Pack 4 and SNA Server version 4.0 Service Pack 3.

MORE INFORMATION

APPC applications which call TP_STARTED before every [MC_]ALLOCATE will not encounter this problem.

This problem occurs in the following conditions:

The LU6.2 session supports either "persistent verification" or "already verified" security.

The APPC application must call TP_STARTED once, followed by consecutive [MC_]ALLOCATE requests, with security = AP_SAME and a user_id and password is specified.

The SNA Server APPC API and message traces will reveal the following behavior. In this case, the APPC application issues three consecutive MC_ALLOCATE requests with security=AP_SAME along with userID and password on a session that supports persistent verification. But, the Wappc32.dll file appears to resend the initial user ID over and over, ignoring the user ID provided by the application:

APPC app issues MC_ALLOCATE, sends userid = WNW039, password = WHYNOT1, FMH-5 includes userid = WNW039, password = WHYNOT1

APPC app issues MC_ALLOCATE, sends userid = WNWXXX, password = YYYY, FMH-5 includes userid = WNW039, password = YYYY

APPC app issues MC_ALLOCATE, sends userid = XXXX, password = ZZZZZ, FMH-5 includes userid = WNW039, password = ZZZZZ

Note that the APPC DLL always sends the same user ID, ignoring the user ID provided in the verb control block by the application.

Additional query words:

Keywords : sna3sp4fix sna4sp3fix
Version : WINDOWS:3.0SP3,4.0,4.0SP1,4.0SP2
Platform : WINDOWS
Issue type : kbbug