irule to rewrite steam in request

 

Hi,

 

 

01070151:3: Rule [req_rep] error:

 

line 10: [parse error: PARSE syntax 381 {syntax error in expression " info exists content_length ": extra tokens at end of expression}] [{ info exists content_length }]

 

Sorry, I had typos in the info exists content_length lines. They should be wrapped in square brackets:

 

 

if { [info exists content_length] } {

 

 

Aaron

Hi,

 

 

dees this rule need a HTTP::release at the end?

 

 

from http://devcentral.f5.com/Wiki/default.aspx/iRules/HTTP__release.html

 

HTTP::collect, the event (HTTP_REQUEST_DATA or HTTP_RESPONSE_DATA) will not fire without HTTP::release being called (at least implicitly).

 

 

Regards

 

Garry

You shouldn't need to use HTTP::release in HTTP_REQUEST_DATA:

 

 

 

http://devcentral.f5.com/Wiki/default.aspx/iRules/HTTP__release.html

 

 

Unless a subsequent HTTP::collect command was issued, there is no need to use the HTTP::release command inside of the HTTP_REQUEST_DATA and HTTP_RESPONSE_DATA events, since (in these cases) the data is implicitly released.

 

 

 

 

Aaron

 

Hi,

 

 

I have tested the rule, the page flows through but i dont get the image that is posted in the form uploaded.

 

 

 

when HTTP_REQUEST {

 

Check if request is a POST

 

if {[HTTP::method] eq "POST"}{

 

Trigger collection for up to 1MB of data

 

if {([HTTP::header exists "Content-Length"]) && ([HTTP::header "Content-Length"] <= 1000000)}{

 

set content_length [HTTP::header "Content-Length"]

 

} else {

 

set content_length 1000000

 

}

 

if { info exists $content_length } {

 

HTTP::collect $content_length

 

}

 

}

 

}

 

when HTTP_REQUEST_DATA {

 

Replace https://... with http://... in the payload

 

HTTP::payload replace 0 [HTTP::payload length] [string map -nocase "https://10.104.30.55 http://10.104.30.55" [HTTP::payload]]

 

}

 

What kind of error/problems do you see? Can you post an anonymized copy of the request headers and body (you can get this using a browser plugin like HttpFox for FF or Fiddler for IE.

 

 

Maybe the problem is that non-text POST requests are being modified. It might be good to add a check so that only POST requests with a Content-Type starting with text are rewritten:

 

 

if {[HTTP::method] eq "POST" && [HTTP::header Content-Type] starts_with "text"}{

 

 

Or is the request a multi-part form upload where the image data is being sent along with the text you're trying to rewrite? If so, the string map command might be corrupting the encoded binary content. You could try using regsub instead:

 

 

HTTP::payload replace 0 [HTTP::payload length] [regsub -all "https://10.104.30.55" [HTTP::payload] "http://10.104.30.55"]

 

 

Anyhow, if you can provide more detail on what's not working and a sample of the requests, I could more detailed suggestions.

 

 

Aaron

Hi All,

 

 

I was getting the headers in order to paste them here when i noteced a double replace. (https://10.104.30.55/10.104.30.55/) which in turn makes (GET /10.104.30.55/@@A07A8D93C5E6F89540D8D494CBE5A933/courses/1/support/content/_235847_1/embedded/big_ub_weblearn2.jpg HTTP/1.1) incorrect

 

 

HTTP/1.x 200 OK

 

Date: Mon, 30 Mar 2009 12:32:01 GMT

 

Server: Replaced

 

Cache-Control: private, max-age=0, no-store, must-revalidate

 

Last-Modified: Mon, 30 Mar 2009 12:32:01 GMT

 

Expires: Sun, 30 Mar 2008 12:32:01 GMT

 

X-testapp-product: test-app™ 7.3.230.0

 

Set-Cookie: session_id=A07A8D93C5E6F89540D8D494CBE5A933; Path=/

 

Keep-Alive: timeout=15, max=100

 

Connection: Keep-Alive

 

Transfer-Encoding: chunked

 

Content-Type: text/html;charset=UTF-8

 

----------------------------------------------------------

 

https://10.104.30.55/10.104.30.55/@@A07A8D93C5E6F89540D8D494CBE5A933/courses/1/support/content/_235847_1/embedded/big_ub_weblearn2.jpg

 

 

GET /10.104.30.55/@@A07A8D93C5E6F89540D8D494CBE5A933/courses/1/support/content/_235847_1/embedded/big_ub_weblearn2.jpg HTTP/1.1

 

Host: 10.104.30.55

 

User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-GB; rv:1.9.0.7) Gecko/2009021910 Firefox/3.0.7

 

Accept: image/png,image/*;q=0.8,*/*;q=0.5

 

Accept-Language: en-gb,en;q=0.5

 

Accept-Encoding: gzip,deflate

 

Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.7

 

Keep-Alive: 300

 

Connection: keep-alive

 

Referer: https://10.104.30.55/webapps/wysiwyg/ch1/inspicture_proc2.jsp?course_id=_55340_1

 

Cookie: __utma=46131897.4054063774627931000.1232525019.1232525019.1232525019.1; __utmz=46131897.1232525019.1.1.utmcsr=(direct)|utmccn=(direct)|utmcmd=(none); JSESSIONID=C579F3709C577B0FCC35F40E5C776DD1.root; session_id=A07A8D93C5E6F89540D8D494CBE5A933

 

 

HTTP/1.x 404 Not Found

 

Date: Mon, 30 Mar 2009 12:32:02 GMT

 

Server: NotReplaced

 

Last-Modified: Wed, 23 Jul 2008 14:16:50 GMT

 

Etag: "2c464-a7d-48873d52;49b8fe09"

 

Accept-Ranges: bytes

 

Keep-Alive: timeout=15, max=98

 

Connection: Keep-Alive

 

Content-Type: text/html

 

Transfer-Encoding: chunked

Which iRule are you testing now? Are you using a stream filter and iRule and/or HTTP::collect? What is your search/replace strings? If you're only replacing http://10.104.30.55 with https://10.104.30.55 on requests and the opposite on responses, I'm not sure how the URI in an image reference would be rewritten to /10.104.30.55.

 

 

Aaron

Hi,

 

I am testing the rule with...

 

HTTP::payload replace 0 [HTTP::payload length] [regsub -all "https://10.104.30.55" [HTTP::payload] "http://10.104.30.55"]

 

I made a slight mistake in the rule so i know why it was putting in the double replace.

 

This is what i did wrong

 

HTTP::payload replace 0 [HTTP::payload length] [regsub -all "https://10.104.30.55" [HTTP::payload] "10.104.30.55"]

 

Anyway the rule is still corrupting any binary objects that are sent in the post. Fron the look of the headers everything is posted as it should be, the replace is happening ok and it works great if i upload a text file. But with images or pdf's for instace i just get a blank/missing file. With images i get the image url repeaded on the screan and FF lists it as an image of the correct type and filesize but with dimensions of 0px x 0px

 

The closest i every got it to working was with the sream rule. This actually showed some of the content of the image but with the rest of it greyed out. I am guessing this was because the content length without the replace was 10996 and after the replace it was set to 4808, so i guess [HTTP::payload length] was 4808. i tried to do an add on the content length

 

HTTP::header replace "Content-Length" [HTTP::header "Content-Length"] +1 but that gave me an invalid content length error. Maybe this is just a syntax thing that i have wrong.

 

when HTTP_REQUEST {

 

if { [HTTP::method] equals "POST" && [HTTP::header exists "Content-Length"] and [HTTP::header "Content-Length"] > 0} {

 

STREAM::expression "@https://10.104.30.55@http://10.104.30.55@"

 

HTTP::header replace "Content-Length" [HTTP::payload length]

 

STREAM::enable

 

} else {

 

STREAM::disable

 

}

 

}

 

Hi All,

 

 

Does anybody know the syntax for math expresions.

 

 

would something like this work?.

 

 

 

when HTTP_REQUEST {

 

x = [HTTP::header "Content-Length"]

 

y = 1

 

 

if { [HTTP::method] equals "POST" && [HTTP::header exists "Content-Length"] and [HTTP::header "Content-Length"] > 0} {

 

STREAM::expression "@https://10.104.30.55@http://10.104.30.55@"

 

HTTP::header replace "Content-Length" [expr {$x+$y}]

 

STREAM::enable

 

} else {

 

STREAM::disable

 

}

 

}