This was brought to my attention by someone in the #postfix IRC channel
the other day and I felt it deserved some testing and passing on. The
postconf(5) docs for the local_recipient_maps setting does not state
whether the keys in this table should include a domain name or just a
username part without the @domain suffix. The setting does, however,
have a default of "proxy:unix:passwd.byname $alias_maps" and since
alias_maps *is* documented to want just the username part and the unix
#passwd file also only contains just the username (without an @domain
suffix) then it can be implied that lookups should work and will be done
on the username part without the @domain suffix, that said...
When a pcre table is added to alias_maps, and local_recipient_maps is
kept at the default which includes $alias_maps, then pcre table entries
appear to be looked up with the @domain suffix for the
local_recipient_maps setting. This is inconsistent with the alias_maps
setting which looks up only the username portion of the address in the
pcre table. This was confirmed with the following test cases:
alias_maps = hash:/etc/aliases pcre:/etc/postfix/alias_test.pcre
local_recipient_maps = proxy:unix:passwd.byname $alias_maps (default)
/etc/postfix/alias_test.pcre:
/^\d{9}$/ pj
$ telnet localhost 25
Trying ::1...
Connected to localhost.
Escape character is '^]'.
220 el7-test.***MASKED***.com ESMTP Postfix
HELO example.com
250 el7-test.***MASKED***.com
MAIL FROM: test@localhost
250 2.1.0 Ok
RCPT TO: 123456789@localhost
550 5.1.1 <123456789@localhost>: Recipient address rejected: User
unknown in local recipient table
QUIT
221 2.0.0 Bye
Connection closed by foreign host.
...changing alias_test.pcre appears to allow the same test above to work:
$ telnet localhost 25
Trying ::1...
Connected to localhost.
Escape character is '^]'.
220 el7-test.***MASKED***.com ESMTP Postfix
HELO example.com
250 el7-test.***MASKED***.com
MAIL FROM: test@localhost
250 2.1.0 Ok
RCPT TO: 123456789@localhost
250 2.1.5 Ok
DATA
354 End data with <CR><LF>.<CR><LF>
To: 123456789@localhost
From: test@localhost
This is a test
.
250 2.0.0 Ok: queued as 7D36790160
QUIT
221 2.0.0 Bye
Connection closed by foreign host.
...but then ends up bouncing (from postfix logs):
May 4 04:39:21 el7-test postfix/smtpd[20796]: connect from el7-test[::1]
May 4 04:40:28 el7-test postfix/smtpd[20796]: 7D36790160:
client=el7-test[::1]
May 4 04:41:23 el7-test postfix/cleanup[20799]: 7D36790160:
message-id=<20150504044028.7D36790160@el7-test.***MASKED***.com>
May 4 04:41:23 el7-test postfix/qmgr[20794]: 7D36790160:
from=<test@localhost>, size=359, nrcpt=1 (queue active)
May 4 04:41:23 el7-test postfix/local[20801]: 7D36790160:
to=<123456789@localhost>, relay=local, delay=59, delays=59/0.02/0/0.01,
dsn=5.1.1, status=bounced (unknown user: "123456789")
May 4 04:41:23 el7-test postfix/bounce[20802]: 7D36790160: sender
non-delivery notification: E33DC901BB
May 4 04:41:23 el7-test postfix/qmgr[20794]: 7D36790160: removed
Adding *both* entries to alias_test.pcre:
/^\d{9}$/ pj
/^\d{9}@localhost$/ pj
... and repeating the above test works:
May 4 04:46:38 el7-test postfix/smtpd[20809]: connect from el7-test[::1]
May 4 04:46:52 el7-test postfix/smtpd[20809]: C44FD90160:
client=el7-test[::1]
May 4 04:47:06 el7-test postfix/cleanup[20812]: C44FD90160:
message-id=<20150504044652.C44FD90160@el7-test.***MASKED***.com>
May 4 04:47:06 el7-test postfix/qmgr[20794]: C44FD90160:
from=<test@localhost>, size=364, nrcpt=1 (queue active)
May 4 04:47:06 el7-test postfix/local[20813]: C44FD90160:
to=<pj@el7-test.***MASKED***.com>, orig_to=<123456789@localhost>,
relay=local, delay=19, delays=19/0.02/0/0, dsn=2.0.0, status=sent
(delivered to mailbox)
May 4 04:47:06 el7-test postfix/qmgr[20794]: C44FD90160: removed
May 4 04:47:09 el7-test postfix/smtpd[20809]: disconnect from
el7-test[::1] helo=1 mail=1 rcpt=1 data=1 quit=1 commands=5
Changing alias_test.pcre back to the original state:
/^\d{9}$/ pj
...and explicitly setting:
local_recipient_maps =
...also allows the message to go through:
May 4 04:51:23 el7-test postfix/local[20832]: AF6C890160:
to=<pj@el7-test.***MASKED***.com>, orig_to=<123456789@localhost>,
relay=local, delay=34, delays=34/0.01/0/0, dsn=2.0.0, status=sent
(delivered to mailbox)
Note this is all on:
mail_version = 3.0.1
...but this also happened with another user in #postfix on (I believe)
an older version of postfix, so it's possible this (bug?) has been in
postfix for quite some time. If this is the case then fixing it could
actually raise backwards compatibility issues which may necessitate
something more complicated than a simple straightforward fix.
Peter
