Re: sender rewrining advice

       internet             internet
     recv. email
          |                    ^
          |                    |
          |                    |
          V                    |
   +------------+       +------+-----+
   |      A     |       |      B     |
   |  mailert   +---1-->|    auth    |
   |  accessmap |       |            |
   |  ldapr     |       |            |
   +------+-----+       +------------+
          |
          |
          |
          V
   +------+-----+
   |      C     |
   |            |
   |  virtuser  |
   |            |
   +------------+
host a: incomming, mx
host b: outgoing, smtp with user auth
host c: user mailboxes, user@example.com (not test@example.com)

 Does MX (host A?) have @example.com in it's relay-domains file (or somehow otherwise in class R)?
 

Indeed. I am trying to use email addresses here and not domains. So NDR are generated on host A / mx server.
I have there, access:
to:test@example.com RELAY
mailertable:
example.com esmtp:[c.local]

mailLocalAddress: test@me.com / test@example.com
mailHost: B
mailRoutingAddress: test@guerrillamail.com

This ldap entry currently makes emails being routed from the mx server A to the outgoing server B

If I'm correctly picking up what you're putting down you are trying to say that mail to test@example.com should be forwarded to test@guerrillamail.com and go out via the OUTGOING server?

correct

I'm going to have to dig out the Bat book and re-read about LDAP routing.

Yes the above does this currently with ldap routing. But I don't know if this is the best way to do it.

---
 I'm confident that MX could relay @example.com to LOCAL and where LOCAL could forward the message to @guerrillamail.com and send it back out.

host C, LOCAL is not in the spf records. I think external access is even blocked. I had spammers by passing spam blocking on the mx / host a and delivering directly to C

Aside:  LOCAL could send the email via MX which would send it on to OUTGOING or perhaps LOCAL could send it directly to OUTGOING.
 

but I have to allow relaying on OUTGOING with something like this in the access map
>
Connect:(MX server)    RELAY

 I think that you can add MX's hostname or IP address to the /etc/mail/relay-domains file.

ok I made note of this, I will enhance this later.

Can you specify ip ranges there or host domains, so you do not do envelope rewriting when it is not necessary?

 The method that I'm using -- I need to log in and copy some files to provide examples -- simply applies sender rewriting to any envelope that is not from a domain that Sendmail is responsible for; /etc/mail/local-host-names (class w).

I am not sure if my outgoing, host b, has access to the local-host-names. It is still using the same clusterid as host c and can probably access the local-host-names.
But I think in the near future I will create a separate clusterid for the outgoing, host b.
(Used to have everything in one host)
At some point in the future I would like to secure host b more, so authenticated users can only send out email with their assigned address.

 They look at the sending envelope address and compare it to the /etc/mail/local-host-names (class w).
 

So currently I am able to route from host a to host b the emails send to test@example.com.
How should I go about to enable SRS for senders to test@example.com on host b?