We’re using an Apache RewriteMap and other rewrite rule directives.
Our issue is that some cookies are incorrect and mixed up between sessions. We think we may have a mutex issue where Apache calls the script multiple times concurrently.
We’re using Apache 2.4.x and it should set a lock to call the script one at a time if certain conditions are set.
How could we figure out for sure if the script gets called only one at a time (the mutex lock works) or if Apache calls it multiple times in parallel.
We’re also see this error in the logs:
[Thu May 09 06:40:01.891518 2024] [rewrite:error] [pid 3732926] [client x.x.x.x:0] AH10410: Rewritten query string contains control characters or spaces
Not sure if that could cause these rewrite issues or it’s independent.
Our rewrite rules are as follows (and yes, they’re long):
##### Session management URL handling
## **** SEE SLM-DISPATCHER-SCRIPTS.README in scripts/dispatcher-scripts ****
###################
Define DTD_DEFAULT_WITH_REFERER 'O99999'
Define DTD_COOKIE_NAME 'slm_dtd_cell'
Define QUERYSTRING_COOKIE_NAME 'slm_qstring'
Define COOKIE_DOMAIN '.salliemae.com'
# SPLIT variable value MUST match value in python script
Define SPLIT 'AsplitA'
###################
### Include supporting python script file for querystring management for the slm_qstring cookie
###################
RewriteMap qstring_rewriter prg:/etc/slm/scripts/slm-sessionmanagement-script.py
###################
### Map http referrer
###################
RewriteCond %{REQUEST_URI} (\/|\.html)$ [NC]
RewriteCond %{HTTP_REFERER} ^.*\.aol.*$ [NC]
RewriteRule ^(.*)$ - [E=referer:A]
RewriteCond %{REQUEST_URI} (\/|\.html)$ [NC]
RewriteCond %{HTTP_REFERER} ^.*ask\..*$ [NC]
RewriteRule ^(.*)$ - [E=referer:K]
RewriteCond %{REQUEST_URI} (\/|\.html)$ [NC]
RewriteCond %{HTTP_REFERER} ^.*google\..*$ [NC]
RewriteRule ^(.*)$ - [E=referer:G]
RewriteCond %{REQUEST_URI} (\/|\.html)$ [NC]
RewriteCond %{HTTP_REFERER} ^.*bing\..*$ [NC]
RewriteRule ^(.*)$ - [E=referer:B]
RewriteCond %{REQUEST_URI} (\/|\.html)$ [NC]
RewriteCond %{HTTP_REFERER} ^.*msn\..*$ [NC]
RewriteRule ^(.*)$ - [E=referer:M]
RewriteCond %{REQUEST_URI} (\/|\.html)$ [NC]
RewriteCond %{HTTP_REFERER} ^.*yahoo\..*$ [NC]
RewriteRule ^(.*)$ - [E=referer:Y]
###################
### Map user agent, only if referrer mapped successfully
###################
RewriteCond %{REQUEST_URI} (\/|\.html)$ [NC]
RewriteCond %{ENV:referer} !^$
RewriteCond %{HTTP_USER_AGENT} ^.*chrome.*$ [NC]
RewriteRule ^(.*)$ - [E=useragent:CHRME]
RewriteCond %{REQUEST_URI} (\/|\.html)$ [NC]
RewriteCond %{ENV:referer} !^$
RewriteCond %{HTTP_USER_AGENT} ^.*firefox.*$ [NC]
RewriteRule ^(.*)$ - [E=useragent:FRFOX]
RewriteCond %{REQUEST_URI} (\/|\.html)$ [NC]
RewriteCond %{ENV:referer} !^$
RewriteCond %{HTTP_USER_AGENT} ^.*opr.*$ [NC]
RewriteRule ^(.*)$ - [E=useragent:OPERA]
RewriteCond %{REQUEST_URI} (\/|\.html)$ [NC]
RewriteCond %{ENV:referer} !^$
RewriteCond %{HTTP_USER_AGENT} !^.*chrome.*$ [NC] #handle Chrome's addition of Safari into its user agent string
RewriteCond %{HTTP_USER_AGENT} !^.*edg.*$ [NC] #handle Edge's addition of Safari into its user agent string
RewriteCond %{HTTP_USER_AGENT} ^.*safari.*$ [NC]
RewriteRule ^(.*)$ - [E=useragent:SFARI]
RewriteCond %{REQUEST_URI} (\/|\.html)$ [NC]
RewriteCond %{ENV:referer} !^$
RewriteCond %{HTTP_USER_AGENT} ^.*MSIE.*$ [NC]
RewriteRule ^(.*)$ - [E=useragent:EXPLR]
RewriteCond %{REQUEST_URI} (\/|\.html)$ [NC]
RewriteCond %{ENV:referer} !^$
RewriteCond %{HTTP_USER_AGENT} ^.*edg.*$ [NC]
RewriteRule ^(.*)$ - [E=useragent:EXPLR]
RewriteCond %{REQUEST_URI} (\/|\.html)$ [NC]
RewriteCond %{ENV:referer} !^$
RewriteCond %{HTTP_USER_AGENT} ^.*wow64.*$ [NC]
RewriteRule ^(.*)$ - [E=useragent:EXPLR]
###################
### Construct dtd_cell code and create/update in cookie
###################
#use any provided dtd_cell from querystring to create/update the dtd_cell cookie
RewriteCond %{REQUEST_URI} (\/|\.html)$ [NC]
RewriteCond %{QUERY_STRING} (^|&)dtd_cell=([^&]+)&?(.*)$ [NC]
RewriteRule ^(.*)$ - [CO=${DTD_COOKIE_NAME}:%2:${COOKIE_DOMAIN}:0:/:secure]
#add to slm_qstring cookie if dtd in querystring and slm_query cookie doesn't exist
RewriteCond %{REQUEST_URI} (\/|\.html)$ [NC]
RewriteCond %{HTTP_COOKIE} !${QUERYSTRING_COOKIE_NAME}=
RewriteCond %{QUERY_STRING} (^|&)dtd_cell=([^&]+)&?(.*)$ [NC]
RewriteRule ^(.*)$ - [CO=${QUERYSTRING_COOKIE_NAME}:${qstring_rewriter:%{QUERY_STRING}${SPLIT}%1}:${COOKIE_DOMAIN}:0:/:secure]
#construct when dtd_cell not in querystring and referer and agent match exists and no dtd cookie exists
RewriteCond %{REQUEST_URI} (\/|\.html)$ [NC]
RewriteCond %{ENV:referer} !^$
RewriteCond %{ENV:useragent} !^$
RewriteCond %{QUERY_STRING} !(^|&)dtd_cell= [NC]
RewriteRule ^(.*)$ - [CO=${DTD_COOKIE_NAME}:%{ENV:referer}${DTD_DEFAULT_WITH_REFERER}%{ENV:useragent}:${COOKIE_DOMAIN}:0:/:secure]
#1 of 2: construct when not in querystring and referer exists and slm_qstring cookie does not exist IF THERE IS NO QUERYSTRING
RewriteCond %{REQUEST_URI} (\/|\.html)$ [NC]
RewriteCond %{ENV:referer} !^$
RewriteCond %{ENV:useragent} !^$
RewriteCond %{QUERY_STRING} ^$
RewriteCond %{HTTP_COOKIE} !${QUERYSTRING_COOKIE_NAME}=
RewriteRule ^(.*)$ - [CO=${QUERYSTRING_COOKIE_NAME}:dtd_cell=%{ENV:referer}${DTD_DEFAULT_WITH_REFERER}%{ENV:useragent}:${COOKIE_DOMAIN}:0:/:secure]
#2 of 2: construct when not in querystring and referer exists and slm_qstring cookie does not exist IF THERE IS A QUERYSTRING
RewriteCond %{REQUEST_URI} (\/|\.html)$ [NC]
RewriteCond %{ENV:referer} !^$
RewriteCond %{ENV:useragent} !^$
RewriteCond %{QUERY_STRING} !^$
RewriteCond %{QUERY_STRING} !(^|&)dtd_cell= [NC]
RewriteCond %{HTTP_COOKIE} !${QUERYSTRING_COOKIE_NAME}=
RewriteRule ^(.*)$ - [CO=${QUERYSTRING_COOKIE_NAME}:dtd_cell=%{ENV:referer}${DTD_DEFAULT_WITH_REFERER}%{ENV:useragent}&%{QUERY_STRING}:${COOKIE_DOMAIN}:0:/:secure]
#construct when not in querystring and referer exists and slm_qstring cookie exists
RewriteCond %{REQUEST_URI} (\/|\.html)$ [NC]
RewriteCond %{ENV:referer} !^$
RewriteCond %{ENV:useragent} !^$
RewriteCond %{QUERY_STRING} !(^|&)dtd_cell= [NC]
RewriteCond %{HTTP_COOKIE} ${QUERYSTRING_COOKIE_NAME}=(.*?(;|$))
RewriteRule ^(.*)$ - [CO=${QUERYSTRING_COOKIE_NAME}:${qstring_rewriter:dtd_cell=%{ENV:referer}${DTD_DEFAULT_WITH_REFERER}%{ENV:useragent}&%{QUERY_STRING}${SPLIT}%1}:${COOKIE_DOMAIN}:0:/:secure]
###################
### Place querystring params in a cookie
###################
# new slm_qstring cookie when we have a qs, but no slm_qstring cookie exists
RewriteCond %{REQUEST_URI} (\/|\.html)$ [NC]
#commenting null referer check per SLMCOM-788946
#RewriteCond %{ENV:referer} ^$
RewriteCond %{QUERY_STRING} !^$
RewriteCond %{HTTP_COOKIE} !${QUERYSTRING_COOKIE_NAME}=
RewriteRule ^(.*)$ - [CO=${QUERYSTRING_COOKIE_NAME}:${qstring_rewriter:%{QUERY_STRING}${SPLIT}%1}:${COOKIE_DOMAIN}:0:/:secure]
###################
### iterate slm_qstring cookie via python
###################
# update slm_qstring cookie when we have a qs, and a slm_qstring cookie exists
RewriteCond %{REQUEST_URI} (\/|\.html)$ [NC]
RewriteCond %{QUERY_STRING} !^$
RewriteCond %{HTTP_COOKIE} ${QUERYSTRING_COOKIE_NAME}=(.*?(;|$))
RewriteRule ^(.*) - [CO=${QUERYSTRING_COOKIE_NAME}:${qstring_rewriter:%{QUERY_STRING}${SPLIT}%1}:${COOKIE_DOMAIN}:0:/:secure]
