Binary Scan help with an iRule

could I just set it as H* or would I need to set some other variable?

Just H* should do it, if I'm not mistaken.

 

 

Colin

Okay that worked but now I am getting the following...man it is a drag when you are new to iRules. Any ideas would be great...

 

 

Jul 19 08:06:51 tmm tmm[1121]: Rule : 0001 iRule RealEC-iRule initialized

 

Jul 19 08:07:17 tmm tmm[1121]: Rule RecDB-iRule2 : 0002 New client connection from 172.20.5.30:3413

 

Jul 19 08:07:17 tmm tmm[1121]: Rule RecDB-iRule2 : 0003 Collecting

 

Jul 19 08:07:17 tmm tmm[1121]: Rule RecDB-iRule2 : 0004 clientdata: 1201003400000000000015000601001b000102001c000c0300280004ff080001550000004d5353514c53657276657200140b0000

 

Jul 19 08:07:17 tmm tmm[1121]: 01220001:3: TCL error: Rule RecDB-iRule2 - can't read "InsertService": no such variable while executing "findstr $clientdata $InsertService 52 "

 

Most of the time I've seen variables in the RULE_INIT section defined with a leading double colon.

when RULE_INIT {
  set ::InsertService "0049006e00730065007200740053006500720076006900630065"
}
...
...
set svc_event [findstr $clientdata $::InsertService 52 ]
 If we see Insert Service set Persist
if { [string first $::InsertService $clientdata] != -1 } {

I know it has something to do with being a global variable; the programmers on the board could explain the details better than me.

Yes, citizen_elah is correct, those should have been defined as global vars, my bad, sorry guys:

when RULE_INIT {
  log local0. "0001 iRule RealEC-iRule initialized"
   Convert Text to HEX before Client_Accepted so we only do this task once.
  set ::InsertService "0049006e00730065007200740053006500720076006900630065"
  set ::TranOrigID "005400720061006e004f00720069006700490044"
  set ::TranRefNum "005400720061006e005200650066004e0075006d"
}
when CLIENT_ACCEPTED {
  log local0. "0002 New client connection from [IP::client_addr]:[TCP::client_port]"
  TCP::collect
  log local0. "0003 Collecting"
}
when CLIENT_DATA {
  binary scan [TCP::payload] H128 clientdata
  log local0. "0004 clientdata: $clientdata"
   Look for InsertService 128 bites into the TCP Payload
  set svc_event [findstr $clientdata $::InsertService 52 ]
   If we see Insert Service set Persist
  if { [string first $::InsertService $clientdata] != -1 } {
     Look for TranOrigID, offset 40 (Hex) and stop at "&" (0x26)
    set trans_id [findstr $clientdata $::TranOrigID 40 "26"]
     Look for TranRefNum, offset 40 (Hex) and stop at "&" (0x26)
    set ref_id [findstr $clientdata $::TranRefNum 40 "26"]
     Concantenate the two values and persist
    set db_id $trans_id:$ref_id
    if { $db_id != "" } {
      log local0. "0005 DB-ID=$db_id"
      persist uie $db_id
      log local0. "Persisting $db_id to [persist lookup uie $db_id]"
      TCP::release
    }
  }
}

Global variables are shared across all connections, so anything that's constant for all connections should be defined as a global variable to save memory. Any variable whose value is expected to vary per connection must be defined as a non-global variable.

HTH

/deb

Here is the irule that I got to work...However, does anyone know how to convert the ASCII into text so that I can just grab the InsertService from the packets?

 

 

when RULE_INIT {

 

log local0. "0001 iRule RealEC-iRule initialized"

 

 

}

 

 

when CLIENT_ACCEPTED {

 

log local0. "0002 New client connection from [IP::client_addr]:[TCP::client_port]"

 

TCP::collect

 

log local0. "0003 Collecting"

 

}

 

 

when CLIENT_DATA {

 

binary scan [TCP::payload] H* clientdata

 

 

Convert Text to HEX before Client_Accepted so we only do this task once.

 

set ::InsertServiceEvent "1201003400000000000015000601001b000102001c000c0300280004ff080001550000004d5353514c53657276657200140b0000"

 

set ::TranOrigID "005400720061006e004f00720069006700490044"

 

set ::TranRefNum "005400720061006e005200650066004e0075006d"

 

 

log local0. "0004 clientdata: $clientdata"

 

 

Look for InsertService 128 bites into the TCP Payload

 

set svc_event [findstr $clientdata $::InsertServiceEvent]

 

 

log local0. "0004a svc_event: $svc_event"

 

 

If we see Insert Service set Persist

 

if { [findstr $clientdata $::InsertServiceEvent] != "" } {

 

Look for TranOrigID, offset 40 (Hex) and stop at &

 

set trans_id [findstr $clientdata $::TranOrigID 40 "26"]

 

 

Look for TranRefNum, offset 40 (Hex) and stop at &

 

set ref_id [findstr $clientdata $::TranRefNum 40 "26"]

 

 

Concantenate the two values and persist

 

set db_id $trans_id:$ref_id

 

 

if { $db_id != "" } {

 

log local0. "0005 DB-ID=$db_id"

 

persist uie $db_id

 

log local0. "Persisting $db_id to [persist lookup uie $db_id]"

 

TCP::release

 

}

 

}

 

}

 

 

when LB_SELECTED {

 

After logic is run and server is selected, log which one

 

log local0. "Selected server [LB::server]"

 

}

 

You can use binary format to convert from HEX encoded ASCII to text. Binary format is just the opposite of binary scan.