Noel Jones wrote:
Vernon A. Fort wrote:
I have a setup which we use an external mail filtering service and need to limit/restrict external client access. Meaning the MX for the domain points to the filtering service and they relay checked email. I need to limit access to just these network blocks but also allow sasl authenticated as well as the internal network.

I also do not want to blindly trust this service so i would like to check the IP address as well as ensuring the recipient is for my domain.

can someone point me to an example or man page. I cannot seem to find anything related to limiting inbound smtp clients/servers.

Vernon

Minimal config:

# main.cf

# do not include filter service IPs in mynetworks
mynetworks = 127.0.0.0/8 ...
smtpd_recipient_restrictions =
  permit_sasl_authenticated
  permit_mynetworks
  reject_unauth_destination
  check_client_access cidr:/etc/postfix/filter_service
  reject

# filter_service
192.1.0.0/24  OK
... other cidr ranges filter service uses ...


  -- Noel Jones
Hey Noel,
 What i have now under the smtpd_*_restrictions:

smtpd_sender_restrictions =
smtpd_client_restrictions =
smtpd_etrn_restrictions = reject
smtpd_recipient_restrictions =
      reject_non_fqdn_sender,
      reject_non_fqdn_recipient,
      permit_sasl_authenticated,
      permit_mynetworks,
      reject_unauth_destination,
      check_helo_access .....
      check_sender_access ...
check_client_access (for white listing client sites - just in case they get rbl listed)
      reject_rbl_client ....
      permit
smtpd_data_restrictions =
      reject_unauth_pipelining,
      permit

What i 'thinking' of is:

smtpd_sender_restrictions =
smtpd_client_restrictions =
      permit_sasl_authenticated,
      permit_mynetworks,
      check_client_access cidr:/etc/postfix/filter_service.cidr,
      reject

The filter_service.cidr would look like
   1.2.3.4/29      OK
   1.2.4.4/29      OK
   0.0.0.0/0        REJECT

Would it be redundant to have the permit_sasl and permit_mynetworks under both the smtpd_client and smtpd_recipient?

Vernon




Reply via email to