#pragma once #include #include extern NSString* error_domain; /** * "Trampoline" class that listens for UDP DNS packets on port 1053 coming from lokinet's embedded * libunbound (when exit mode is enabled), wraps them via NetworkExtension's crappy UDP API, then * sends responses back to libunbound to be parsed/etc. This class knows nothing about DNS, it is * basically just a UDP packet forwarder. * * So for a lokinet configuration of "upstream=1.1.1.1", when exit mode is OFF: * - DNS requests go to TUNNELIP:53, get sent to libunbound, which forwards them (directly) to the * upstream DNS server(s). * With exit mode ON: * - DNS requests go to TUNNELIP:53, get send to libunbound, which forwards them to 127.0.0.1:1053, * which encapsulates them in Apple's god awful crap, then (on a response) sends them back to * libunbound. * (This assumes a non-lokinet DNS; .loki and .snode get handled before either of these). */ @interface LLARPDNSTrampoline : NSObject { // The socket libunbound talks with: uv_udp_t request_socket; // The reply address. This is a bit hacky: we configure libunbound to just use single address // (rather than a range) so that we don't have to worry about tracking different reply addresses. @public struct sockaddr reply_addr; // UDP "session" aimed at the upstream DNS @public NWUDPSession* upstream; // Apple docs say writes could take time *and* the crappy Apple datagram write methods aren't // callable again until the previous write finishes. Deal with this garbage API by queuing // everything than using a uv_async to process the queue. @public int write_ready; @public NSMutableArray* pending_writes; uv_async_t write_trigger; } - (void)startWithUpstreamDns:(NWUDPSession*)dns listenPort:(uint16_t)listenPort uvLoop:(uv_loop_t*)loop completionHandler:(void (^)(NSError* error))completionHandler; - (void)flushWrites; - (void)dealloc; @end