[telnet] Re: telneting to smtp mail servers.

Hi,

Here are the steps required:
- tell the server the machine you are
- give envelope details
- send the message
- quit

- tell the server the machine

This is done via helo command.  It is usually important to make sure
that the helo command you give has a matching PTR record in the DNS
for spamming reasons

- Envelope

Mail from and rcpt to commands are given, multiple recipients can be
specified, bcc's can be done by giving multiple envelope recipients
but not indicating them in the message header.  Note the SMTP server
couldn't kare about the mail headers.

- Data
Data is followed by the message headers, a single blank line, and then
a . on a line by itself.

- quit
the two commands rset and quit should be used to terminate the SMTP
connection.

Example 1:

| telnet mail.hodgsonfamily.org 25
| Out: 220 hodgsonfamily.org Ready for action (Mailtraq 2.0.0.1278/SMTP)
| In: helo andrew.hodgsonfamily.org
| Out: 250 hodgsonfamily.org
| In: mail from: <andrew@xxxxxxxxxxxxxxxxx>
| Out: 250 receiving from andrew@xxxxxxxxxxxxxxxxx
| In: rcpt to: <telnet@xxxxxxxxxxxxx>
| Out: 250 will send to telnet@xxxxxxxxxxxxx
| In: data
| Out: 354 send the message, terminate with "."
| In: From: Andrew Hodgson <andrew@xxxxxxxxxxxxxxxxx>
| In: To: <telnet@xxxxxxxxxxxxx>
| In: Subject: Telnet test 1
| In:=20
| In: Hi all,
| In: This is an SMTP test with the helo argument matching the PTR record=
 of
| In: our DNS server.  Check the received headers of this message.
| In:=20
| In: Andrew.
| In: .
| Out: 250 received the message, thanks
| In: rset
| Out: 250 clearing sender and recipient list, go ahead
| In: quit
| Out: 221 have a nice day (SMTP Closing)

Example2 (I have not done in and out structure for this one):

| 220 hodgsonfamily.org Ready for action (Mailtraq 2.0.0.1278/SMTP)
| helo meow
| 250 hodgsonfamily.org
| mail from: <andrew@xxxxxxxxxxxxxxxxx>
| 250 receiving from andrew@xxxxxxxxxxxxxxxxx
| rcpt to: <telnet@xxxxxxxxxxxxx>
| 250 will send to telnet@xxxxxxxxxxxxx
| data
| 354 send the message, terminate with "."
| From: Andrew Hodgson <andrew@xxxxxxxxxxxxxxxxx>
| To: <telnet@xxxxxxxxxxxxx>
| Subject: Telnet test 2
|=20
| Hi,
| This is a test with the helo argument not matching the PTRE (PTR) =
record.
| Also, another thing to note about Telnet is that if you make a mistake,
| you cannot backspace!!!  (Hense my previous mistake above).
| Andrew.
| .
| 250 received the message, thanks
| rset
| 250 clearing sender and recipient list, go ahead
| quit
| 221 have a nice day (SMTP Closing)

Hope this helps,
Andrew.
--=20
Andrew Hodgson, Bromyard, Herefordshire, UK.
Email: andrew@xxxxxxxxxxxxxxxxx
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