Comment 4 for bug 1657897

Yes that is the correct issue occurring effectively pam never sees the rhost data from sendmail which can be seen in the auth log.

Jan 25 16:56:12 uvt-yakkety saslauthd[3020]: pam_unix(smtp:auth): authentication failure; logname= uid=0 euid=0 tty= ruser= rhost= user=powersj

I did some more investigating into this issue. From what I can tell the saslauthd client never sends the rhost to the saslauthd process and it isn't supported in the client/server protocol. So this is somewhat of a problem because of the design of the protocol and maintaining backwards compatibility with existing clients.