pop3, imap4d – Internet mail servers


upas/pop3 [ –d debugfile ][ –a mailbox ][ –r peeraddr ][ –t tlscertfile ][ –p ]

upas/imap4d [–acpv] [–d smtpdomain] [–s servername]

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 protocol. The options are:
dcreate debugfile and write debugging output to it
acauses pop3 to assume that it already authenticated and to read mailbox immediately
rcauses pop3 to create the file /mail/ratify/trusted/peeraddr#32 to allow subsequent SMTP sessions from that address. See ratfs(4) for details.
tget the local TLS certificate from the file tlscertfile.
pallow passwords in the clear for authenticating the connection

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:
aAssume the user is already authenticated. By default, the user must authenticate using CRAM–MD5 or securenet(8) challenge/response authentication.
cAllow plan 9 challenge response authentication.
pAllow login authentication. This option should only be 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 policy.
vTurn on verbose output to the debug file.
sThe server's name. If none is provided, cs (see ndb(8)) is queried or /env/sysname is used.
dThe 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.

/sys/log/imap4d                   debugging output


aliasmail(8), faces(1), filter(1), mail(1), marshal(1), mlmgr(1), nedmail(1), qer(8), rewrite(6), send(8), upasfs(4)

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 command SYNC that deletes messages flagged for deletion without ending the conversation.