Wietse Venema:
> Wietse Venema:
> > However, when luser_relay handes mail for a non-existent recipient,
> > and it is configured with a non-existent local user, then the local
> > delivery agent will go through the same code path twice with the
> > same address, in which case the duplicate suppressor will silently
> > terminate the recursion like it does for all other deliveries.
> >
> > This may or may not be easy to fix. For now, don't configure
> > luser_relay with a non-existent address, just like postmaster, if
> > you don't want errors to go unreported.
>
> Easy enough: I was able to fix this on the train. If luser_relay
> specifies a non-existent local address, then the luser_relay feature
> becomes a black hole. This was introduced three months after the
> first public release, on 19990302. This patch should apply to every
> supported Postfix release.
The patch needs to be updated for the case that luser_relay specifies
a bare address (no @domain). I'll revisit this in the next day or so.
Wietse
> diff '--exclude=man' '--exclude=html' '--exclude=README_FILES'
> '--exclude=INSTALL' '--exclude=.indent.pro' '--exclude=Makefile.in' -r -ur
> /var/tmp/postfix-3.4-20180222/src/local/unknown.c src/local/unknown.c
> --- /var/tmp/postfix-3.4-20180222/src/local/unknown.c 2015-01-11
> 15:30:20.000000000 -0500
> +++ src/local/unknown.c 2018-03-06 17:06:17.477496641 -0500
> @@ -78,6 +78,8 @@
>
> #include "local.h"
>
> +#define STREQ(x,y) (strcasecmp((x),(y)) == 0)
> +
> /* deliver_unknown - delivery for unknown recipients */
>
> int deliver_unknown(LOCAL_STATE state, USER_ATTR usr_attr)
> @@ -140,6 +142,13 @@
> state.msg_attr.unmatched = 0;
> expand_luser = vstring_alloc(100);
> local_expand(expand_luser, var_luser_relay, &state, &usr_attr, (void *)
> 0);
> + /* Assumes that the address resolver will not change the address. */
> + if (STREQ(vstring_str(expand_luser), state.msg_attr.rcpt.address)) {
> + dsb_simple(state.msg_attr.why, "5.1.1",
> + "unknown user: \"%s\"", state.msg_attr.user);
> + return (bounce_append(BOUNCE_FLAGS(state.request),
> + BOUNCE_ATTR(state.msg_attr)));
> + }
> status = deliver_resolve_addr(state, usr_attr, STR(expand_luser));
> vstring_free(expand_luser);
> return (status);
> @@ -149,8 +158,6 @@
> * If no alias was found for a required reserved name, toss the message
> * into the bit bucket, and issue a warning instead.
> */
> -#define STREQ(x,y) (strcasecmp(x,y) == 0)
> -
> if (STREQ(state.msg_attr.user, MAIL_ADDR_MAIL_DAEMON)
> || STREQ(state.msg_attr.user, MAIL_ADDR_POSTMASTER)) {
> msg_warn("required alias not found: %s", state.msg_attr.user);
>
