@Matt thanks for the clarifications! @burhanshakir I've used this lib to modify DNS packets: https://github.com/heyvito/dns. If you wanna use EDNS(0) options, packets must follow this: https://tools.ietf.org/html/rfc6891

@burhanshakir yes, I use that lib with minor changes for iOS project and it works pretty good

Hi, @meaton. Thanks for the reply. The Network System Extension prompt can be auto-allowed with MDM, but the Network Configuration prompt cannot on macOS. Does it mean that it is impossible to make DNS proxy workable without user interaction, even if the user's Mac is enrolled to MDM ?