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#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/wait.h>
#include <signal.h>
#include <pthread.h>
#include "addr.h"
#include "server.h"
#include "resolver.h"
#include "../io/log.h"
#include "../io/map.h"
#include "../io/config.h"
static pthread_t udp, tcp;
static RecordMap map;
void server_init(uint16_t port, Server* server) {
INFO("Server port set to %hu", port);
create_binding(UDP, port, &server->udp);
create_binding(TCP, port, &server->tcp);
if (load_config("/etc/wrapper.conf", &map)) {
return;
}
if (load_config("config", &map)) {
return;
}
WARN("No dns config files were found");
}
struct DnsRequest {
Connection connection;
Packet request;
};
static void* server_respond(void* arg) {
struct DnsRequest req = *(struct DnsRequest*) arg;
INFO("Recieved packet request ID %hu", req.request.header.id);
Packet response;
handle_query(&req.request, &response, req.connection.type, &map);
if (!write_connection(&req.connection, &response)) {
ERROR("Failed to respond to connection ID %hu: %s",
req.request.header.id,
strerror(errno)
);
}
free_packet(&req.request);
free_connection(&req.connection);
if (response.header.z == false) {
free_packet(&response);
} else {
// Dont free from config
free(response.questions);
free(response.answers);
free(response.authorities);
free(response.resources);
}
return NULL;
}
static void* server_listen(void* arg) {
Binding* binding = (Binding*) arg;
while(1) {
Connection connection;
if (!accept_connection(binding, &connection)) {
ERROR("Failed to accept connection");
continue;
}
Packet request;
if (!read_connection(&connection, &request)) {
ERROR("Failed to read connection");
free_connection(&connection);
continue;
}
struct DnsRequest req;
req.connection = connection;
req.request = request;
pthread_t thread;
if(pthread_create(&thread, NULL, &server_respond, &req)) {
ERROR("Failed to create thread for dns request ID %hu: %s",
request.header.id,
strerror(errno)
);
free_packet(&request);
free_connection(&connection);
continue;
}
pthread_detach(thread);
}
pthread_detach(pthread_self());
return NULL;
}
static void signal_handler() {
printf("\n");
pthread_kill(udp, SIGTERM);
pthread_kill(tcp, SIGTERM);
}
void server_run(Server* server) {
if (!pthread_create(&udp, NULL, &server_listen, &server->udp)) {
INFO("Listening for connections on UDP");
} else {
ERROR("Failed to start UDP thread");
exit(EXIT_FAILURE);
}
if (!pthread_create(&tcp, NULL, &server_listen, &server->tcp)) {
INFO("Listening for connections on TCP");
} else {
ERROR("Failed to start TCP thread");
exit(EXIT_FAILURE);
}
signal(SIGINT, signal_handler);
pthread_join(udp, NULL);
pthread_join(tcp, NULL);
pthread_exit(0);
}
void server_free(Server* server) {
free_binding(&server->udp);
free_binding(&server->tcp);
record_map_free(&map);
}
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