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/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
/***
This file is part of systemd.
Copyright 2005-2008 Lennart Poettering
Copyright 2014 Daniel Buch
systemd is free software; you can redistribute it and/or modify it
under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.
systemd is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <stdio.h>
#include <netinet/in.h>
#include <arpa/nameser.h>
#include <resolv.h>
#include <assert.h>
#include <signal.h>
#include <errno.h>
#include "socket-util.h"
#include "sd-resolve.h"
#include "resolve-util.h"
#include "macro.h"
static int getaddrinfo_handler(sd_resolve_query *q, int ret, const struct addrinfo *ai, void *userdata) {
const struct addrinfo *i;
assert(q);
if (ret != 0) {
log_error("getaddrinfo error: %s %i\n", gai_strerror(ret), ret);
return 0;
}
for (i = ai; i; i = i->ai_next) {
_cleanup_free_ char *addr = NULL;
assert_se(sockaddr_pretty(i->ai_addr, i->ai_addrlen, false, &addr) == 0);
puts(addr);
}
printf("canonical name: %s\n", strna(ai->ai_canonname));
return 0;
}
static int getnameinfo_handler(sd_resolve_query *q, int ret, const char *host, const char *serv, void *userdata) {
assert(q);
if (ret != 0) {
log_error("getnameinfo error: %s %i\n", gai_strerror(ret), ret);
return 0;
}
printf("Host: %s -- Serv: %s\n", strna(host), strna(serv));
return 0;
}
static int res_handler(sd_resolve_query *q, int ret, unsigned char *answer, void *userdata) {
int qdcount, ancount, len;
const unsigned char *pos = answer + sizeof(HEADER);
unsigned char *end = answer + ret;
HEADER *head = (HEADER *) answer;
char name[256];
assert(q);
if (ret < 0) {
log_error("res_query() error: %s %i\n", strerror(errno), errno);
return 0;
}
if (ret == 0) {
log_error("No reply for SRV lookup\n");
return 0;
}
qdcount = ntohs(head->qdcount);
ancount = ntohs(head->ancount);
printf("%d answers for srv lookup:\n", ancount);
/* Ignore the questions */
while (qdcount-- > 0 && (len = dn_expand(answer, end, pos, name, 255)) >= 0) {
assert(len >= 0);
pos += len + QFIXEDSZ;
}
/* Parse the answers */
while (ancount-- > 0 && (len = dn_expand(answer, end, pos, name, 255)) >= 0) {
/* Ignore the initial string */
uint16_t pref, weight, port;
assert(len >= 0);
pos += len;
/* Ignore type, ttl, class and dlen */
pos += 10;
GETSHORT(pref, pos);
GETSHORT(weight, pos);
GETSHORT(port, pos);
len = dn_expand(answer, end, pos, name, 255);
printf("\tpreference: %2d weight: %2d port: %d host: %s\n",
pref, weight, port, name);
pos += len;
}
return 0;
}
int main(int argc, char *argv[]) {
_cleanup_resolve_query_unref_ sd_resolve_query *q1 = NULL, *q2 = NULL, *q3 = NULL;
_cleanup_resolve_unref_ sd_resolve *resolve = NULL;
int r = 0;
struct addrinfo hints = {
.ai_family = PF_UNSPEC,
.ai_socktype = SOCK_STREAM,
.ai_flags = AI_CANONNAME
};
struct sockaddr_in sa = {
.sin_family = AF_INET,
.sin_port = htons(80)
};
assert_se(sd_resolve_default(&resolve) >= 0);
/* Make a name -> address query */
r = sd_resolve_getaddrinfo(resolve, &q1, argc >= 2 ? argv[1] : "www.heise.de", NULL, &hints, getaddrinfo_handler, NULL);
if (r < 0)
log_error("sd_resolve_getaddrinfo(): %s\n", strerror(-r));
/* Make an address -> name query */
sa.sin_addr.s_addr = inet_addr(argc >= 3 ? argv[2] : "193.99.144.71");
r = sd_resolve_getnameinfo(resolve, &q2, (struct sockaddr*) &sa, sizeof(sa), 0, SD_RESOLVE_GET_BOTH, getnameinfo_handler, NULL);
if (r < 0)
log_error("sd_resolve_getnameinfo(): %s\n", strerror(-r));
/* Make a res_query() call */
r = sd_resolve_res_query(resolve, &q3, "_xmpp-client._tcp.gmail.com", C_IN, T_SRV, res_handler, NULL);
if (r < 0)
log_error("sd_resolve_res_query(): %s\n", strerror(-r));
/* Wait until the three queries are completed */
while (sd_resolve_query_is_done(q1) == 0 ||
sd_resolve_query_is_done(q2) == 0 ||
sd_resolve_query_is_done(q3) == 0) {
r = sd_resolve_wait(resolve, (uint64_t) -1);
if (r < 0) {
log_error("sd_resolve_wait(): %s\n", strerror(-r));
assert_not_reached("sd_resolve_wait() failed");
}
}
return 0;
}
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