Forum Discussion
uni
Altocumulus
AltocumulusRewrite redirects to issuing host
I have an https virtual which forwards to an http server, hence I need to rewrite redirects when they point back to the issuing server.
"rewrite all" does not work because the server may issue a redirect to an external http site, and must not be rewritten to https.
"rewrite matching" is not suitable because sometimes the redirect uri does not match the request uri, i.e. a JSESSIONID may be appended to the original uri.
Consequently, I have to come up with an iRule which only rewrites the redirect when the redirection is back to the same host. Could someone have a look at my attempt below and tell me if I'm on the right track?
when HTTP_REQUEST {
set host [HTTP::host];
log LOCAL0.debug "URI=$host";
}
when HTTP_RESPONSE {
if { [HTTP::status] starts_with "3" } {
set location [HTTP::header "Location"];
if { $location starts_with "http://" } {
set temp [substr $location 8];
HTTP::header replace "Location" "https://$temp";
}
}
}3 Replies
- dennypayne
Employee
As you have it, it will perform just as "rewrite all" does, but once you work in some logic to check the [HTTP::host] in the response (either against a static entry or a list using matchclass) it should work fine.
Denny 
uniGood point. I must have been distracted by the phone.
What I should have posted is this:when HTTP_REQUEST { set host [HTTP::host]; log LOCAL0.debug "URI=$host"; } when HTTP_RESPONSE { if { [HTTP::status] starts_with "3" } { set location [HTTP::header "Location"]; if { $location starts_with "http://" } { set temp [substr $location 7]; if { $host equals [substr $temp 0 "/"] }{ HTTP::header replace "Location" "https://$temp"; } } } }
Will [substr $temp 0 "/"] return the trailing "/"? If so, can anyone suggest an efficient way of dropping it?
Sorry to ask such simple, testable, questions. Unfortunately I don't have a test environment and will only have a short testing window when I put this in production.- uniTo answer my own question, when the terminator in a substr call is a character, the string returned does not include the terminator. If the terminator is an integer, that many characters are returned.
So [substr "abcdef" 0 "d"] returns "abc", and [substr "abcdef" 0 3] also returns "abc".
