POP3(8) POP3(8)
NAME
pop3, imap4d - Internet mail servers
SYNOPSIS
upas/pop3 [ -d debugfile ][ -a mailbox ][ -r peeraddr ][ -t
tlscertfile ][ -p ]
upas/imap4d [-acpv] [-d smtpdomain] [-s servername]
DESCRIPTION
These programs support remote access to mail across the
Internet. All expect the network connection to be standard
input, output, and error. They are normally started from
scripts in /rc/bin/service (see listen(8)).
Pop3 provides access to a user's mailboxes via the POP3 pro-
tocol. The options are:
-d create debugfile and write debugging output to it
-a causes pop3 to assume that it already authenticated and
to read mailbox immediately
-r causes pop3 to create the file
/mail/ratify/trusted/peeraddr#32 to allow subsequent
SMTP sessions from that address. See ratfs(4) for
details.
-t get the local TLS certificate from the file tlscertfile.
-p allow passwords in the clear for authenticating the con-
nection
Imap4d provides access to a user's mailboxes via the
IMAP4rev1 protocol. Only files rooted in
/mail/box/username/ are accessible. The list of subscribed
mailboxes is contained in
/mail/box/username/imap.subscribed, and initially contains
only INBOX, IMAP's name for the user's mailbox. A shadow
file, mailbox.imp, is created for each mailbox examined.
Imap4d's options are:
a Assume the user is already authenticated. By default,
the user must authenticate using CRAM-MD5 or
securenet(8) challenge/response authentication.
c Allow plan 9 challenge response authentication.
p Allow login authentication. This option should only be
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POP3(8) POP3(8)
enabled for servers using an encrypted connection, such
as SSL, and when enabled, all non-encrypted connections
should be disallowed. Imap4d does not enforce this pol-
icy.
v Turn on verbose output to the debug file.
s The server's name. If none is provided, cs (see ndb(8))
is queried or /env/sysname is used.
d The local mail domain. Defaults to the server /env/site
in the mail server's domain.
For both imap4d and pop3, the password used to authenticate
the connection is the APOP secret held by keyfs(4) running
on the authentication server.
FILES
/sys/log/imap4d debugging output
/mail/box/username/mailbox
/mail/box/username/mailbox.imp
/mail/box/username/imap.subscribed
SOURCE
/sys/src/cmd/upas/pop3
/sys/src/cmd/upas/imap4d
SEE ALSO
aliasmail(8), faces(1), filter(1), mail(1), marshal(1),
mlmgr(1), nedmail(1), qer(8), rewrite(6), send(8), upasfs(4)
BUGS
Usually messages flagged for deletion with DELE are not
actually deleted until the client sends a QUIT command to
end the conversation. Pop3 implements a non-standard com-
mand SYNC that deletes messages flagged for deletion without
ending the conversation.
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