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#include "client.h"
#include "../packet/question.h"
#include "addr.h"
#include "binding.h"
#include <resolv.h>
#include <stdio.h>
#include <stdlib.h>
#include <assert.h>
#include <string.h>
#include <time.h>
#include <errno.h>
#include <sys/time.h>
void resolve_default_server(IpAddr* addr) {
res_init();
addr->data.v4 = _res.nsaddr_list[0].sin_addr;
addr->type = V4;
}
static void push_question(Question** buf, Question q, uint8_t* amount, uint8_t* capacity) {
if (*amount >= *capacity) {
*capacity *= 2;
*buf = realloc(*buf, sizeof(Question) * *capacity);
}
(*buf)[*amount] = q;
(*amount)++;
}
void resolve_questions(int argc, char** argv, uint8_t* len, Question** questions) {
assert(argc > 0);
uint8_t amount = 0;
uint8_t capacity = 1;
Question* buf = malloc(sizeof(Question) * capacity);
Question q;
RecordType t;
if (argc == 1 && str_to_qtype(argv[0], &t)) {
create_question("", NS, &q);
push_question(&buf, q, &amount, &capacity);
*questions = buf;
*len = 1;
return;
}
for (int i = 0; i < argc; i++) {
if (str_to_qtype(argv[i], &t)) {
if (i + 1 == argc) break;
create_question(argv[i+1], t, &q);
i++;
} else if (i + 1 < argc && str_to_qtype(argv[i+1], &t)){
create_question(argv[i], t, &q);
i++;
} else {
create_question(argv[i], A, &q);
}
push_question(&buf, q, &amount, &capacity);
}
*questions = buf;
*len = amount;
}
static void print_result(Packet* packet, const char* type, uint32_t ms) {
printf(">> Recieved response\n");
printf("Id: %hu, Code: %s\n",
packet->header.id,
str_from_code(packet->header.rescode)
);
printf("Questions: %hu, Answers: %hu, Authorities: %hu, Resources: %hu\n",
packet->header.questions,
packet->header.answers,
packet->header.authoritative_entries,
packet->header.resource_entries
);
if (packet->header.questions > 0) {
printf("\n>> Question Section\n");
for (uint16_t i = 0; i < packet->header.questions; i++) {
print_question(&packet->questions[i]);
}
}
if (packet->header.answers > 0) {
printf("\n>> Answer Section\n");
for (uint16_t i = 0; i < packet->header.answers; i++) {
print_record(&packet->answers[i]);
}
}
if (packet->header.authoritative_entries > 0) {
printf("\n>> Authority Section\n");
for (uint16_t i = 0; i < packet->header.authoritative_entries; i++) {
print_record(&packet->authorities[i]);
}
}
if (packet->header.resource_entries > 0) {
printf("\n>> Resource Section\n");
for (uint16_t i = 0; i < packet->header.resource_entries; i++) {
print_record(&packet->resources[i]);
}
}
printf("\n>> Query time: %ums (%s)\n", ms, type);
}
void resolve(IpAddr server, Options options, Question* questions, uint8_t len) {
struct timeval stop, start;
gettimeofday(&start, NULL);
SocketAddr addr;
create_socket_addr(options.port, server, &addr);
Packet req;
memset(&req, 0, sizeof(Packet));
srand(time(NULL));
req.header.id = rand() % 65536;
req.header.questions = len;
req.header.recursion_desired = true;
req.questions = questions;
Connection conn;
if (options.force_tcp) goto tcp;
if (!create_request(UDP, &addr, &conn)) {
printf("error: failed to create udp request: %s\n", strerror(errno));
exit(EXIT_FAILURE);
}
Packet res;
if (!request_packet(&conn, &req, &res)) {
free_request(&conn);
free_packet(&req);
printf("error: failed to request udp packet: %s\n", strerror(errno));
exit(EXIT_FAILURE);
}
free_request(&conn);
if (!res.header.truncated_message) {
gettimeofday(&stop, NULL);
uint32_t ms = (stop.tv_sec - start.tv_sec) * 1000000 + stop.tv_usec - start.tv_usec;
print_result(&res, "UDP", ms / 1000);
free_packet(&req);
free_packet(&res);
return;
}
free_packet(&res);
printf("Response truncated, retrying in TCP...\n");
tcp:
if (!create_request(TCP, &addr, &conn)) {
printf("error: failed to create tcp request: %s\n", strerror(errno));
exit(EXIT_FAILURE);
}
if (!request_packet(&conn, &req, &res)) {
free_request(&conn);
printf("error: failed to request tcp packet: %s\n", strerror(errno));
exit(EXIT_FAILURE);
}
gettimeofday(&stop, NULL);
uint32_t ms = (stop.tv_sec - start.tv_sec) * 1000000 + stop.tv_usec - start.tv_usec;
print_result(&res, "TCP", ms / 1000);
free_request(&conn);
free_packet(&req);
free_packet(&res);
}
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