Forum Discussion
Eric_27859
Nimbostratus
NimbostratusX-Forwarded-For and Route Domains issue with '%'
Hello,
I'm using the header X-Forwarded-For to tell the server the remote client IP (using AutoMap in the Virtual Server). When a Route Domain is involved, all the IPs are written with this format "IP%RouteDomainID". I've searched in the Wiki for IP::client_addr and the IP::addr ussage and didn't found how to extract in an easy manner the IP without the Route Domain. I also tried to use TCL string last, string trim and another string functions but without success.
Would you give me a hint about how should I get only the IP without the route domain?
Thank you in advance!
10 Replies
- The_BhattmanHi Eric,
You can do this in an irule. Specifically split command with a string and scan command. You can find these commands on the following link http://www.tcl.tk/man/tcl8.4/TclCmd/contents.htm
I hope this helps,
Bhattman 
Kevin_Davies_40Nacreous
I assume you want the X-Forwarded-For address updated yes? Try this and let me know how it goes.
when HTTP_REQUEST {
HTTP::header replace {X-Forwarded-For} [ getfield [HTTP::header {X-Forwarded-For}] {%} 1 ]
}- Kevin_Davies_40I assume you want the X-Forwarded-For address updated yes? Try this and let me know how it goes.
when HTTP_REQUEST {
HTTP::header replace {X-Forwarded-For} [ getfield [HTTP::header {X-Forwarded-For}] {%} 1 ]
} - The_BhattmanHI Jarvil,
Yes sorry about that. I, for some reason, misunderstood your question.
Yes your correct taht HTTP::header command along with getfield will work
Here is the typical code where you insert the field instead of replace itwhen HTTP_REQUEST { HTTP::header insert X-Forwarded-For [getfield [IP::client_addr] "%" 1] }
Bhattman - Kevin_Davies_40Hi Bhattman,
If he is already using the header X-Forwarded-For tcp profile option as stated, wouldn't the HTTP::header insert leave him with a duplicate header?
Regards
Jarvil - The_BhattmanHi Jarvil,
Good question. I never tested it with the option turned on so, I suppose either you see 2 values or just one.
Bhattman - Kevin_Davies_40You will see two X-Forwarded-For values as I just tested it. So the best solution is likely...
when HTTP_REQUEST {
HTTP::header replace X-Forwarded-For [getfield [IP::client_addr] "%" 1]
} 
Eric_27859Sorry about my absence.
The key about my problem is "getfield" command that I wasn't aware of. I need to insert the HTTP header X-Forwarded-For, but as Jarvil pointed right, maybe this header is coming yet within the original request arriving to F5. In that case I would rather replace the header value.
If the server log supports it, I will concatenate the arriving X-Forwarded-For value with the new one, separating with a coma, but I think that this maybe is not necessary regarding the actual server logs.
Thank you all for your help!!- Eric_27859Sorry about my absence.
The key about my problem is "getfield" command that I wasn't aware of. I need to insert the HTTP header X-Forwarded-For, but as Jarvil pointed right, maybe this header is coming yet within the original request arriving to F5. In that case I would rather replace the header value.
If the server log supports it, I will concatenate the arriving X-Forwarded-For value with the new one, separating with a coma, but I think that this maybe is not necessary regarding the actual server logs.
I will try this and update how this goes.
Thank you all for your help!! - Kevin_Davies_40maybe this header is coming yet within the original request arriving to F5
Actually its coming from the X-Forward-For setting in your HTTP profile whiich adds the header for you. Hence we need to update it and not add another one.
