Squashed commit of the following:

commit dd36206e13cc16c384ce65e5060efb069c4794a7
Author: Stanislav Chzhen <s.chzhen@adguard.com>
Date:   Wed Jul 26 16:32:45 2023 +0300

    upstream: imp code

commit a1236088
Author: Stanislav Chzhen <s.chzhen@adguard.com>
Date:   Tue Jul 25 19:38:15 2023 +0300

    upstream: add opts root cas