postfix filter function with amavis smtpd-proxy

[Damian]

> i read, that the postfix filter action function doesn't work with amavis as a smtpd-proxy, only as a content-filter
> is this correct?

If by "smtpd-proxy" you mean smtpd_proxy_filter, then amavis can be used
as such.

> if yes, how can i create a virus and spam whitelist for some {senders,domains,hosts}?
> all my attempts to create a whitelist failed.

For spam whitelisting there is $per_recip_whitelist_sender_lookup_tables
and @whitelist_sender_maps (and some related legacy confvars). For
viruses, I am only aware of @virus_lovers_maps (and some related legacy
confvars).