Finer Control with V8.10

Prior to V8.10, the lefthand side of the access database could contain only a user, host, domain, or address, and would only look them up based on the client name or address, the MAIL From: address, or the RCPT To: address.

Beginning with V8.10, sendmail offers much finer control of addresses and rejections in the access database. The lefthand side of the access database can begin with one of three possible prefixes:[132]

Connect:

The address is either the IP address or the hostname of a connecting host.

From:

The address is that of an envelope sender.

To:

The address is that of an envelope recipient.

When an address is looked up in the access database, it is first looked up with the prefix. If it is not found, it is looked up again without a prefix, meaning that the old access databases will still work with newer versions of sendmail. To illustrate, consider this update to the access database shown in the previous section:

From:spamuser@hotmail.com    REJECT
From:cybermarkets.com        REJECT
Connect:example.org          REJECT
Connect:192.168.212          REJECT

This access database will cause mail from to be rejected. Mail from any user at cybermarkets.com will be rejected, connections from the host example.org will be rejected, and any mail from any host with an IP address ranging from 192.168.212.0 through 192.168.212.255 will have the initial connection rejected. In that last example, any missing righthand part of an IP address is assumed to be a wildcard for matching ...

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