F-SECURE INTERNET GATEKEEPER FOR LINUX 4.01 Administrator's Manual page 152

EHLO command
1 The following is sent to the server: EHLO [Host name]
2 Receives a response from the server.
3 The following option lines are deleted from the response information.
CHUNKING, BINARYMIME, PIPELINING,STARTTLS
4 Set the response and maximum message size to the smallest value (default: 2,000,000,000) from
the server in the SIZE option.
5 If proxy authentication is enabled, add the following option line to the response information.
250-AUTH PLAIN LOGIN
6 The following is sent to the client: [Response information]
MAIL command
1 If the syntax of the command is invalid:
① The following is sent to the client: 501 Syntax error (MAIL FROM:) ([Product name])
2 The following is sent to the server: [Client response information]
3 Receives a response from the server.
4 The following is sent to the client: [Server response information]
RCPT command
1 If the syntax of the command is invalid:
① The following is sent to the client: 500 RCPT command must begin with "RCPT TO:" ([Product
name])
2 If recipient domains are restricted and authentication is not complete
(Recipient (RCPT) domain restrictions are enabled and PbS (POP-before-SMTP)/SMTP
authentication is not complete (destination domains and domain connections from the LAN are not
related))
① The following is sent to the client: 550 Relaying denied. ([Product name])
3 The following is sent to the server: [Client response information]
4 Receives a response from the server.
5 The following is sent to the client: [Server response information]
6 If the response code is other than 250:
① The session ends.
AUTH command
1 If SMTP authentication is enabled:
① If authentication passes:
1) The following is sent to the client: 235 ok authed ([Product name])
② If authentication fails:
1) The following is sent to the client: 535 authorization failed ([Product name])
③ If the authentication method is other than PLAIN or LOGIN:
1) The following is sent to the client: 504 this mechanism not available ([Product name])
2 If SMTP authentication is disabled:
① The authentication request and response are transferred between the server and client.
F-Secure Internet Gatekeeper for Linux/Administrator's Guide
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