dns.h

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/*
 * Copyright (C) 2017 Kaspar Schleiser <kaspar@schleiser.de>
 *
 * This file is subject to the terms and conditions of the GNU Lesser
 * General Public License v2.1. See the file LICENSE in the top level
 * directory for more details.
 */
 
#ifndef NET_SOCK_DNS_H
#define NET_SOCK_DNS_H
 
#include <errno.h>
#include <stdint.h>
#include <unistd.h>
 
#include "net/sock/udp.h"
 
#ifdef __cplusplus
extern "C" {
#endif
 
typedef struct {
    uint16_t id;        
    uint16_t flags;     
    uint16_t qdcount;   
    uint16_t ancount;   
    uint16_t nscount;   
    uint16_t arcount;   
    uint8_t payload[];  
} sock_dns_hdr_t;
 
#define DNS_TYPE_A              (1)
#define DNS_TYPE_AAAA           (28)
#define DNS_CLASS_IN            (1)
 
#define SOCK_DNS_PORT           (53)
#define SOCK_DNS_RETRIES        (2)
 
#define SOCK_DNS_BUF_LEN        (128)       /* we're in embedded context. */
#define SOCK_DNS_MAX_NAME_LEN   (SOCK_DNS_BUF_LEN - sizeof(sock_dns_hdr_t) - 4)
 
int sock_dns_query(const char *domain_name, void *addr_out, int family);
 
extern sock_udp_ep_t sock_dns_server;
 
#ifdef __cplusplus
}
#endif
 
#endif /* NET_SOCK_DNS_H */