Chapter 7. Handle Spam and Filter with Milter

What’s New with V8.13

V8.13 has been augmented in several ways that benefit your ability to detect and reject spam email.

  • The confREJECT_MSG mc macro no longer auto-inserts quotation marks around its value (Section 7.1.1 [V8.13]).

  • Envelope quarantining has been added as a means to hold mail for review. (See Section 11.1.2 [V8.13] for a complete discussion of quarantining.)

  • The Milter library has been enhanced by the addition of a smfi_quarantine( ) routine (Section 7.1.2.1 [V8.13]), a smfi_progress( ) routine (Section 7.1.2.2 [V8.13]), a smfi_stop( ) routine (Section 7.1.2.3 [V8.13]), a smfi_setdbg( ) routine (Section 7.1.2.4 [V8.13]), a smfi_setmlreply( ) routine (Section 7.1.2.5 [V8.13]), a smfi_setbacklog( ) routine (Section 7.1.2.6 [V8.13]) and a smfi_opensocket( ) routine(Section 7.1.2.7[V8.13]). Support for a 421 SMTP return (Section 7.1.2.9 [V8.13]) has been added, the removal of the socket by root (Section 7.1.2.10[V8.13]) has been prevented, and macros may now be passed to a Milter’s end-of-message routine (Section 24.1.17 [V8.13]).

  • The check_relay ruleset (7.1.1[3ed]) is now called with the value of ${client_name} macro (21.9.20[3ed]) so that it can deal with bogus DNS entries (Section 9.1.2 [V8.13]).

  • The new greet_pause feature allows protection from SMTP slamming (Section 7.1.3 [V8.13]).

  • The new (experimental) mtamark feature implements MTA marking by looking up TXT records in the in-addr.arpa domain (Section 7.1.4 [V8.13]

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