After a lot of work, I was able to solve this myself. I updated the previously linked Stack Overflow link with the solution, but am copying it here for completeness.
For anyone that has a similar issue, I was finally able to solve the problem myself.
My Apache Version was 2.4.6 but the most recent RHEL Version, httpd-2.4.6-97.el7.centos I believe. Looking at the Change Log for apache 2.4 (https://www.apachelounge.com/Changelog-2.4.html)
most of the mod_authz_dbd changes were included
in the CentOS version except for the one integrated in Apache 2.4.17 entitled
*) mod_authz_dbd: Avoid a crash when lacking correct DB access permissions.
PR 57868. [Jose Kahan < jose w3.org>, Yann Ylavic]
Interestingly, this type of crash seemed to similarly describe the type of crash I was observing, though my DB access permissions were correct.
I followed the instructions here (https://crosp.net/blog/administration/install-latest-apache-server-centos-7/)
to install Apache 2.4.46. Getting this updated version of Apache solved my problem using the exact same .conf file
listed above. Unfortunately, my Apache now doesn't have the benefits of RHEL if I go this route, but I'm assuming this bug fix in Apache 2.4.17 is tied to the error I was seeing.
Either way, I figured it was worth mentioning the solution I was able to obtain in case anyone else runs into a similar issue.
From: Kyle Hansen <Kyle.R.Hansen@xxxxxxxxxxxx>
Sent: Tuesday, February 2, 2021 7:54 PM
To: users@xxxxxxxxxxxxxxxx
Subject: Apache authorization using require dbd-group from SQL Server database
I have an app running behind a reverse proxy on Apache 2.4.6 on CentOS 7. I am doing authentication using Shibboleth
and am currently doing authorization via a whitelist using AuthGroupFile /path/to/authfile and Require
group authGroup. This currently works with my setup. I'm trying to change this process to do authorization against a whitelist stored in a SQL Server database, and this
is proving to be difficult. I had assumed I could just replace AuthGroupFile /path/to/authfile
with AuthzDBDQuery “SELECT appName FROM authTable
WHERE UserLogin = %s” and replace
Require group authGroup with
Require dbd-group myApp but that does not seem to be working as expected.
Currently in conf.d/shib.conf I
have the following:
DBDriver odbc
DBDParams "DATASOURCE=ODBCconn,USER=myUser,PASSWORD=myPwd"
<Location /authLocation>
AuthType shibboleth
ShibRequestSetting requireSession 1
Require dbd-group myApp
AuthzDBDQuery "SELECT appName FROM authTable WHERE UserLogin = %s"
</Location>
My with my DSM ODBCconn I
am using ODBC Driver 17 for SQL Server and I can
use that DSM to connect using those credentials via pyodbc in python, so I think I have that setup correctly. In the database, the column appName will
return the name of the applications the user is authorized to use as stored in authTable,
or essentially the groups the user is a part of. Hence, if a user has a row for myApp they
will be authorized to use myApp. My understanding
of the documentation (https://httpd.apache.org/docs/trunk/mod/mod_authz_dbd.html) is this is how my query
should work for defining a group.
However, when running this I get a stack smashing error in
my httpd/logs/error_log that looks something like:
*** stack smashing detected ***: /usr/sbin/httpd terminated
======= Backtrace: =========
...
...
Long long list of files
...
...
[Thu Jan 28 09:36:53.306151 2021] [core:notice] [pid 10621] AH00052: child pid 24810 exit signal Aborted (6)
[Thu Jan 28 09:36:53.306215 2021] [core:notice] [pid 10621] AH00052: child pid 28192 exit signal Aborted (6)
[Thu Jan 28 09:36:53.306238 2021] [core:notice] [pid 10621] AH00052: child pid 31928 exit signal Aborted (6)
Any help on what might be going wrong with my setup that is preventing authorization in this way?
Additionally posted on Stack Overflow without responses yet (https://stackoverflow.com/questions/65945922/apache-authorization-using-require-dbd-group-from-sql-server-database)
Kyle Hansen, PhD
Email: kyle.r.hansen@xxxxxxxxxxxx
