Forum Discussion
Maxim_Taskov_90
Nov 15, 2011Nimbostratus
Client Certificate Validation by Subject
I am trying to use the common name CN from the x509::subject variable to validate a client certificate. I used the rule from teh following post as a sample:
http://devcentral.f5.com/Communit...
Maxim_Taskov_90
Nov 16, 2011Nimbostratus
Thanks for th reply nitass. You are probably right, why is it >1?! Anyway, I changed it to >0 and it made no difference, I still get the following TCL error when a certificate with blank subject field is presented and the connection is allowed:
Nov 16 14:34:57 tmm tmm[1672]: 01220001:3: TCL error: ebilling_client_cert_check - command returned bad code: 32 while executing "if {[SSL::cert count] > 1}{ set subject_dn [X509::subject [SSL::cert 0]] log local0. "Client Certificate Received: $subject_dn" if {$s..."
Pretty good hack!
After looking at the iRule I thought that maybe "if {[SSL::cert count] > 0 and [SSL::cert 0] ne ""}" statement is at fault as the subject_dn variable will not be populated if [SSL::cert 0] is blank, so then later on when we check for it in "if {$subject_dn eq ""}", the TCL engine has no idea what to do. Well, I removed the "and [SSL::cert 0] ne ""}" part and still got the same TCL error and the connection was allowed/accepted. I hope I am not running into some king of iRule/TCL anomaly as I need to get this running soon and this looks like a serious security vulnerability.
I hope you guys have some additional ideas.
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