Interpret existing symbols in own lua code

[Jochen F.]

Hi,

I found that many spam, that cannot be rejected by postscreen and rbls, has a unique feature: they are sent through freemailers (mainly gmail in my case) with a freemail From: and a different freemail Reply-To:

So I wrote my own lua rule to compare From: and Reply-To: addresses. The function FREEMAIL_REPLYTO_NEQ_FROM_DOM does a similar thing, but only compares the domain, not the entire address. Inspired by that I wrote a similar function:

-- Requires freemail maps loaded in multimap
local function freemail_reply_neq_from_addr(task)
  local frt = task:get_symbol('FREEMAIL_REPLYTO')
  local ff  = task:get_symbol('FREEMAIL_FROM')
  local reply_to = task:get_header('Reply-To')
  local mail_from = task:get_from()
  if (frt and ff and reply_to ~= mail_from)
  then
    return true
  end
  return false
end




rspamd_config:register_symbol({
  name = 'FREEMAIL_REPLYTO_NEQ_FROM',
  callback = freemail_reply_neq_from_addr,
  description = 'Freemail From and Reply-To, but to different Freemail addresses',
  score = 10.0,
  group = 'headers',
})
rspamd_config:register_dependency('FREEMAIL_REPLYTO_NEQ_FROM', 'FREEMAIL_REPLYTO')
rspamd_config:register_dependency('FREEMAIL_REPLYTO_NEQ_FROM', 'FREEMAIL_FROM')

But I'm asking me, if I could not get the Reply-To-address from the HAS_REPLYTO symbol the same way like the "task:get_symbol('FREEMAIL_REPLYTO')"? I don't know what the "task:get_header('Reply-To')" exactly returns. Propably it will also contain a display name if there, but I need the native mail address for the compare.

Is it possible to get the mail address form the FREEMAIL_REPLYTO symbol? How? How must the code rewritten?