Adding to header and PDU content

Hi Tim,

 

 

Inserting the header should just be a matter of using 'HTTP::header insert start {}' (Click here).

 

 

Are you wanting to insert the Content-ID in a header or the HTTP data? If it's the header, you can use the HTTP::header insert command again. If the latter, you would need to collect the payload and then use HTTP::payload replace. Deb posted a codeshare example for inserting content in the response. You could adapt this for the request.

 

 

InsertContentIntoServerResponse (Click here).

 

 

Aaron

Hey Aaron,

 

 

The Contentid is in the HTTP data, and the start="" is in the HTTP header but needs to be at the end of the line as shown in the example, I am checking out the links now.

 

 

Thanks for the advice.

 

 

Tim

Aaron,

 

 

maybe like this?

 

 

when HTTP_REQUEST {

 

Insert Missing HTTP tag.

 

HTTP::payload replace 0 0 "; start="""

 

}

 

 

when HTTP_REQUEST_DATA {

 

Add missing pdu content.

 

HTTP::payload replace 0 0 "Content-ID: "

 

}

 

 

I am a little unsure how to make the HTTP::replace apend to the end of the line instead of adding the content at the begining of the Header. From the wiki pages:

 

 

HTTP::payload replace

 

 

* Replaces the amount of content that you specified with the argument, starting at with , adjusting the Content-Length header appropriately.

 

 

The offset is this in characters? How do I take into account line breaks?

 

 

Tim

 

Ok I think this is going to do what I want, but the "" that are needed to be written how do I specify them?

 

 

when HTTP_REQUEST {

 

Insert Missing HTTP tag.

 

set old-data [HTTP::header value "Content-Type"]

 

HTTP::header remove "Content-Type"

 

HTTP::header insert "Content-Type""$old-data""; start="""

 

}

 

 

when HTTP_REQUEST_DATA {

 

Add missing pdu content.

 

HTTP::payload replace 0 0 "Content-ID: "

 

}

 

 

Tim

To insert the header, you can use the HTTP_REQUEST event:

when HTTP_REQUEST {
    Insert HTTP header
   HTTP::header insert start {}
}

To insert the string in the payload, I thought you needed to collect the HTTP data first. I'm actually a bit surprised to see in the codeshare example HTTP::payload replace being used in the HTTP_RESPONSE event (as opposed to HTTP_RESPONSE_DATA).

If you do need to collect the data in order to modify the payload, I think it would actually be more efficient to use a stream profile to 'replace' a known string in the payload with that string plus what you want to insert.

Here's what I'm thinking for the rule:

when HTTP_REQUEST {
    Check if the request is a POST to a specific path with a content type containing "xml"
   if {[HTTP::path] starts_with "/mms-rs" and [HTTP::method] eq "POST" and [HTTP::header value "Content-Type" contains "xml"}{
       Insert HTTP header
      HTTP::header insert start {}
       Enable the stream profile and set the find/replace strings
      STREAM::enable
      STREAM::expression {@Content-Type:text/xml; charset="utf-8"@Content-Type:text/xml; charset="utf-8"...Content-ID: @}
   }
}

The rule requires a blank stream profile added to the virtual server.

The stream expression format is described on the wiki page (Click here).

The only catch, is that I haven't figured out how to insert a carriage return and line feed where the three periods are in the STREAM::expression. I'm not sure if you could insert a \r\n, the value in hex 0D0A, or something else altogether. I can't test this right now to see either.

Aaron

Aaron,

 

 

I am going to give this a try and see what happens

 

 

rule mm7 {

 

 

when HTTP_REQUEST {

 

 

if {[HTTP::path] starts with "/mmsc/mm7" and [HTTP::method] eq POST}{

 

 

Insert Missing HTTP tag.

 

set old-data [HTTP::header value "Content-Type"]

 

set missing [; start=""]

 

HTTP::header remove "Content-Type"

 

HTTP::header insert "Content-Type""$old-data""$missing"

 

 

Add missing pdu content

 

STREAM::enable

 

STREAM::expression {@Content-Type:text/xml; charset="utf-8"@Content-Type:text/xml; charset="utf-8"\r\nContent-ID: @}

 

}

 

}

 

}

 

 

Tim

 

This is what I have now, the objectives have changed slightly, but I have an issue:

 

 

when HTTP_REQUEST {

 

 

 

if {([HTTP::path] starts_with "/mmsc/mm7") and ([HTTP::method] eq

 

"POST")}{

 

 

read out boundry

 

set tblength [string first "Content-Type" [HTTP::payload]]

 

set blength [expr {$tblength - 4}]

 

set bdary [substr [HTTP::payload] 2 $blength]

 

 

Insert Missing HTTP tag.

 

set olddata [HTTP::header value "Content-Type"]

 

set missing "start=\"\";"

 

HTTP::header replace "Content-Type" "$olddata

 

boundary=\"$bdary\"; $missing"

 

 

Add missing pdu content

 

insert Content-ID

 

set tmp [string first "Content-Type" [HTTP::payload] ]

 

set bypass [expr {$tmp + 37}]

 

HTTP::payload replace $bypass 0 "\r\nContent-ID:

 

"

 

 

insert CID:

 

set bypass2 [string first "comverse.cid" [HTTP::payload] ]

 

HTTP::payload replace $bypass2 0 "cid:"

 

 

fix boundry in payload

 

set tbypass3 [string first ".boundary=" [HTTP::payload] ]

 

log local0. "$tbypass3"

 

set bypass3 [expr {$tbypass3 - 2}]

 

if {$bypass3 > 0}{

 

HTTP::payload replace $bypass3 3 " "

 

}

 

 

}

 

}

 

 

The fix boundry in payload section never finds the actual string .boundry, is there some limitations on how much HTTP::payload can read? if not what do you think is wrong with this?

 

 

Tim