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Ajay_Koushik_19's avatar
Ajay_Koushik_19
Icon for Nimbostratus rankNimbostratus
Apr 06, 2015

iRule to modify SMTP mail content

Hi, We have an requirement, where in we need to inspect the incoming SMTP message, look for a particular string and based on that modify the mail content. I have written the below iRule but this is not working. The CLIENT_DATA event is being triggered. I refered to the SMTP proxy iRule provided in this link(https://devcentral.f5.com/wiki/iRules.SMTPProxy.ashx?NS=iRules). I am not sure if i am missing anything here.

 

when CLIENT_ACCEPTED {

 

TCP::respond "220\r\n" TCP::collect 2000 } when CLIENT_DATA { set cdata [TCP::payload] if { $cdata starts_with "DATA" } { if { [string match "Exchange2010R2" $cdata ]} {

 

string map {"Sent From:" "Sent From:\nExchange 2010 R2 Server\n"} TCP::payload

 

}

 

} TCP::release TCP::collect }

 

Thanks in Advance. Ajay

 

application delivery
devops
irule
iRules
smtp
smtp proxy
string map

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  • Seth_Cooper's avatar
    Seth_Cooper
    Icon for Employee rankEmployee
    Apr 06, 2015

    I haven't tested this but try something like this below. I would also recommend adding logging statements as you process through and get your iRule working correctly. This will be a timesaver as you troubleshoot and debug.

    when CLIENT_ACCEPTED {
  TCP::respond "220\r\n" 
  TCP::collect 2000 
} 

when CLIENT_DATA { 
  set cdata [TCP::payload] 
  if { $cdata starts_with "DATA" } { 
    if { $cdata contains "Exchange2010R2" } {
      set new_payload [string map {"Sent From:" "Sent From:\nExchange 2010 R2 Server\n"} $cdata]
      TCP::payload replace 0 0 $new_payload
    }
  } 
  TCP::release 
  TCP::collect 
}

    Seth