HTTP Basic auth backends now do both authn and authz
in order to allow provide a means to extend backends to optionally
support group authz
x-ref:
"LDAP-Group support for HTTP-Authentication"
https://redmine.lighttpd.net/issues/1817
Note: http_auth_backend_t digest interface returns result as a
binary MD5 (16-bytes) so that caller consistently converts to
lowercase before using it in further digest calculation.
(Alternatively, the http_auth_backend_t digest interface could have
taken a 33-char buffer and returned an explicitly lowercased hex str)
create new, extensible interface for (additional) auth backends
attempt to handle HANDLER_WAIT_FOR_EVENT returned by auth backends
to allow for async auth backends (e.g. to mysql database)
separate auth backends from mod_auth and http_auth
mod_authn_file.c htdigest, htpasswd, plain auth backends
mod_authn_ldap.c ldap auth backend
add http_auth.c to common_sources for auth backend registration
(mod_authn_file could be three separate modules, but no need for now)
Glenn Strauss