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SNI in sol13452 and Default / fallback client ssl profile
how to Drop https request for Default / fallback clientssl profile, SNI in sol13452 sol13452 describes very well for "Configuring a virtual server to serve multiple HTTPS sites using the TLS Server Name Indication feature" but solution does not say about if I do not want the connection to establish when required hostname (CN / servername) is not coming from client request then how to drop the connection. Should I use iRule or profile parameter tweak will enable this feature.
Hi Neeraj,
I'm not aware of a configuration hack to bypass the mandatory SNI Default Profile. But you may use the iRule below as a starting point, to parse the requested SNI value and then allow/reject the connection as needed...
when CLIENTSSL_CLIENTHELLO { if { [SSL::extensions exists -type 0] } then { switch -glob -- [string range [SSL::extensions -type 0] 9 end] { "site1.domain1.de" - "site2.domain1.de" - "site3.domain1.de" - "*.domain2.de" { log local0.debug "SNI Check: Allowing SNI Value = \"[string range [SSL::extensions -type 0] 9 end]\"" Allow the request } default { log local0.debug "SNI Check: Blocking SNI Value = \"[string range [SSL::extensions -type 0] 9 end]\"" reject } } } }
Note: You have to configure "Require Peer SNI support" in your Client SSL Profiles to block any CLIENTHELLO's without SNI extentions.
Cheers, Kai
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