Sendmail 8.9.3 Release Notes

Chapter 1 17
New and Changed Features
New Features
This option will allow eight bit header when set to TRUE. This option
is mainly used to allow eight bit characters in the header line of a
mail message.
This option is set using:
O EightBitHeader = TRUE
This option is commented in the default sendmail.cf file.
Support for New Mailer Delivery Agent and Map
Sendmail 8.9.3 supports the following:
• Discard
A special internal delivery agent named discard is now defined for
use with check_* rulesets and header checking rulesets.
If a mail address resolves to the $#discard mailer then, all the
SMTP commands (MAIL FROM and RCPT TO) will be accepted but the
message will be completely discarded. Therefore, if only one of the
recipient address resolves to the $#discard mailer, all the other
recipients will not receive the mail since the entire mail envelope will
be discarded.
• Regular Expressions
Sendmail-8.9.3 supports regular expressions using the new map class
regex. The regex map can be used to see if an address matches a
certain regular expression. By using such a map in a check_* ruleset,
you can block a certain range of addresses that would otherwise be
considered valid.
For example: If you want to block all senders with all numerics
usernames (i.e. [e-mail]), you would use
Local_check_mail and the new regex map. An example is shown
below.
LOCAL_CONFIG
Kallnumbers regex -a@MATCH ^[0-9]+$
LOCAL_RULESETS
SLocal_check_mail # check address against various regex
checks
• Class R