Cisco Cisco Email Security Appliance C170 Guia Do Utilizador

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Cisco AsyncOS 8.5 for Email User Guide
 
Chapter 18      Email Authentication
  Enabling SPF and SIDF
See the Cisco AsyncOS CLI Reference Guide for more information on the 
listenerconfig
 command.
The Received-SPF Header
When you configure AsyncOS for SPF/SIDF verification, it places an SPF/SIDF verification header 
(
Received-SPF
) in the email. The 
Received-SPF
 header contains the following information:
verification result - the SPF verification result (see 
identity - the identity that SPF verification checked: HELO, MAIL FROM, or PRA.
receiver - the verifying host name (which performs the check).
client IP address - the IP address of the SMTP client.
ENVELOPE FROM - the envelope sender mailbox. (Note that this may be different from the MAIL 
FROM identity, as the MAIL FROM identity cannot be empty.)
x-sender - the value of the HELO, MAIL FROM, or PRA identity.
x-conformance - the level of conformance (see 
) and whether a downgrade of the PRA check was performed. 
The following example shows a header added for a message that passed the SPF/SIDF check:
Note
The 
spf-status
 and 
spf-passed
 filter rules use the received-SPF header to determine the status of the 
SPF/SIDF verification. 
      SoftFail, Fail, TempError, PermError: Reject
    For MAIL FROM Identity: Accept
  SMTP Response Settings:
    Reject code: 550
    Reject text: #5.7.1 SPF unauthorized mail is prohibited.
    Get reject response text from publisher: Yes
    Defer code: 451
    Defer text: #4.4.3 Temporary error occurred during SPF verification.
  Verification timeout: 40
Received-SPF: Pass identity=pra; receiver=box.example.com;
    client-ip=1.2.3.4; envelope-from="alice@fooo.com";
    x-sender="alice@company.com"; x-conformance=sidf_compatible