lokinet/include/llarp/dnsd.hpp
2018-09-24 06:09:01 -07:00

94 lines
2.6 KiB
C++

#ifndef LIBLLARP_DNSD_HPP
#define LIBLLARP_DNSD_HPP
#include <llarp/ev.h> // for sockaadr
#include <string>
#include "dns.hpp" // question and dnsc
#include "dnsc.hpp"
// fwd declaration
struct dnsd_context;
/// sendto hook functor
typedef ssize_t (*sendto_dns_hook_func)(void *sock, const struct sockaddr *from,
const void *buffer, size_t length);
/// DNS server query request
struct dnsd_question_request
{
/// sock type
void *user;
// raw or llarp subsystem
bool llarp;
/// request id
int id;
/// question being asked
dns_msg_question question;
// request source socket
struct sockaddr *from;
sendto_dns_hook_func sendto_hook; // sendto hook tbh
// maybe a reference to dnsd_context incase of multiple
dnsd_context *context; // or you can access it via user (udp)
};
// FIXME: made better as a two way structure, collapse the request and response
// together
struct dnsd_query_hook_response
{
/// turn off communication
bool dontSendResponse;
/// turn off recursion
bool dontLookUp;
/// potential address
sockaddr *returnThis;
};
/// intercept query hook functor
typedef dnsd_query_hook_response *(*intercept_query_hook)(
std::string name, const struct sockaddr *from,
struct dnsd_question_request *request);
/// DNS Server context
struct dnsd_context
{
/// DNS daemon socket to listen on
struct llarp_udp_io udp;
/// udp tracker
struct dns_tracker *tracker;
/// upstream DNS client context to use
dnsc_context client;
/// custom data for intercept query hook (used for configuration of hook)
void *user;
/// hook function for intercepting dns requests
intercept_query_hook intercept;
};
/// udp event handler
void
llarp_handle_dnsd_recvfrom(struct llarp_udp_io *udp,
const struct sockaddr *addr, const void *buf,
ssize_t sz);
/// for hook functions to use
void
writecname_dnss_response(std::string cname, const struct sockaddr *from,
dnsd_question_request *request);
void
writesend_dnss_response(struct sockaddr *hostRes, const struct sockaddr *from,
dnsd_question_request *request);
/// initialize dns subsystem and bind socket
/// returns true on bind success otherwise returns false
bool
llarp_dnsd_init(struct dnsd_context *dnsd, struct llarp_logic *logic,
struct llarp_ev_loop *netloop, const char *dnsd_ifname,
uint16_t dnsd_port, const char *dnsc_hostname,
uint16_t dnsc_port);
/// shutdowns any events, and deallocates for this context
bool
llarp_dnsd_stop(struct dnsd_context *dnsd);
#endif