mongoose/src/dns.h
2022-03-06 14:31:42 +00:00

39 lines
1.2 KiB
C

#pragma once
#include "net.h"
#include "str.h"
// Mongoose sends DNS queries that contain only one question:
// either A (IPv4) or AAAA (IPv6) address lookup.
// Therefore, we expect zero or one answer.
// If `resolved` is true, then `addr` contains resolved IPv4 or IPV6 address.
struct mg_dns_message {
uint16_t txnid; // Transaction ID
bool resolved; // Resolve successful, addr is set
struct mg_addr addr; // Resolved address
char name[256]; // Host name
};
struct mg_dns_header {
uint16_t txnid; // Transaction ID
uint16_t flags;
uint16_t num_questions;
uint16_t num_answers;
uint16_t num_authority_prs;
uint16_t num_other_prs;
};
// DNS resource record
struct mg_dns_rr {
uint16_t nlen; // Name or pointer length
uint16_t atype; // Address type
uint16_t aclass; // Address class
uint16_t alen; // Address length
};
void mg_resolve(struct mg_connection *, const char *url);
void mg_resolve_cancel(struct mg_connection *);
bool mg_dns_parse(const uint8_t *buf, size_t len, struct mg_dns_message *);
size_t mg_dns_parse_rr(const uint8_t *buf, size_t len, size_t ofs,
bool is_question, struct mg_dns_rr *);