UPAS(8) UPAS(8)
NAME
upas, rmail, translate - mail delivery system
SYNOPSIS
rmail person ...
/usr/lib/upas/translate name
/usr/lib/upas/auth sender receiver
DESCRIPTION
Users send mail by mail(1). Remote machines use rmail. Both
call on upas programs.
Mail addresses are interpreted according to rewrite rules as
described below. When the addresses for a mail or rmail
command have been interpreted, they are bundled by network
and passed to network-specific handlers, such as route.inet.
Translate looks up a mail name in an alias list (see
mail(6)) and places the result on standard output.
Auth is called by upas to authorize mail delivery for each
sender, receiver pair. The mail is accepted if the previous
hop was a trusted gateway machine in or all the machines in
the source or destination path are in
Rewrite rules
Each line of the file is a rule. Blank lines and lines
beginning with # are ignored.
Each rewriting rule consists of (up to) 4 strings:
pattern
A regular expression in the style of regexp(3). The
pattern is applied to mail destination addresses. The
pattern match is case-insensitive and must match the
entire address.
type The type of rule; see below.
arg1 An ed(1) style replacement string, with \n standing for
the text matched by the nth parenthesized subpattern.
arg2 Another ed(1) style replacement string.
In each of these fields the substring `\s' is replaced by
the login id of the sender and the substring `\l' is
replaced by the name of the local machine.
UPAS(8) UPAS(8)
When delivering a message, mail starts with the first rule
and continues down the list until a pattern matches the des-
tination address. It then performs one of the following
actions depending on rule type:
>> Append the mail to the file indicated by expanding
arg1, provided that file appears to be a valid mailbox.
| Pipe the mail through the command formed from concate-
nating the expanded arg1 and arg2.
alias
Replace the address by the address(es) specified by
expanding arg1 and recur.
translate
Replace the address by the address(es) output by the
command formed by expanding arg1 and recur.
auth Call the program in expanded arg1 and authorize(reject)
the mail if it returns a zero(non-zero) return code.
Mail expands the addresses recursively until each address
has matched a `>>' or `|' rule or until the recursion depth
indicates a rewriting loop (currently 32).
An `auth' operator is only applied once per address. If no
`auth' rule is encountered, the mail is accepted.
If several addresses match `|' rules and result in the same
expanded arg1, the message is delivered to all those
addresses by a single command, composed by concatenating the
common expanded arg1 and each expanded arg2. This is meant
to make less work of a message to several recipients on the
same machine. For example, the rule
([^!]+)!(.+) | "uux - -a \s \1!rmail" \2
causes `mail r70!pjw r70!ken' to generate the single deliv-
ery command `uux -a rob r70!rmail pjw ken'.
EXAMPLES
A sample rewrite file:
# local mail
[^!@%]+ translate "exec translate '&'"
local!([^!@%]+) >> /usr/spool/mail/\1
\l!(.+) alias \1
# convert %@ format to ! format
(_822_)!((.+)!)?([^!]+)[%@]([^!%@]+) \
alias \1!\2\5!\4
([^!]+)[%@]([^!@%]+) alias _822_!\2!\1
_822_!(.+) alias \1
# special domains
[^!]+wisc\.edu!.+ alias xunet!&
UPAS(8) UPAS(8)
# network gateways
(csnet|bitnet)!(.+) alias inet!&
acsnet!.+
# real networks
inet!([^!]+)!(.+) | "/usr/lib/upas/route.inet '\s' '\1'" "'\2'"
([^!]+)!(.+) | "/usr/lib/upas/route '\s' '\1'" "'\2'"
FILES
list of files to search
private aliases
rewriting rules
known AT&T machines
machines that check mail authorization reliably
alias lookup
mail interfaces to specific networks
interface to local (i.e. AT&T) Datakit network
shell file that calls the mailer
actually delivery program
linked to /usr/lib/upas/send
mailboxes
delivery logs
updates various mail and uucp files
authentication
temp file
lock file
unmailable text
SEE ALSO
uucp(1), mail(1), mail(6), smtp(8)
D. L. Presotto and W. R. Cheswick, `Upas-a simpler approach
to network mail', this manual, Volume 2