icbd/dns.c

135 lines
3.6 KiB
C

/*
* Copyright (c) 2014 Mike Belopuhov
*
* ASR implementation and OpenSMTPD integration are copyright
* Copyright (c) 2008 Gilles Chehade <gilles@poolp.org>
* Copyright (c) 2009 Jacek Masiulaniec <jacekm@dobremiasto.net>
* Copyright (c) 2011-2012 Eric Faurot <eric@faurot.net>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF MIND, USE, DATA OR PROFITS, WHETHER IN
* AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
* OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/time.h>
#include <netinet/in.h>
#include <errno.h>
#include <event.h>
#include <resolv.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include "asr.h"
#include "icb.h"
#include "icbd.h"
struct async_event;
struct async_event *async_run_event(struct async *,
void (*)(int, struct async_res *, void *), void *);
void dns_done(int, struct async_res *, void *);
extern int dodns;
void
dns_done(int ev __attribute__((__unused__)), struct async_res *ar, void *arg)
{
struct icb_session *is = arg;
if (ar->ar_gai_errno == 0) {
icbd_log(is, LOG_DEBUG, "dns resolved %s to %s", is->host,
is->hostname);
if (strncmp(is->hostname, "localhost",
sizeof "localhost" - 1) == 0)
strlcpy(is->host, "unknown", ICB_MAXHOSTLEN);
else if (strlen(is->hostname) < ICB_MAXHOSTLEN)
strlcpy(is->host, is->hostname, ICB_MAXHOSTLEN);
} else
icbd_log(is, LOG_WARNING, "dns resolution failed: %s",
gai_strerror(ar->ar_gai_errno));
}
void
dns_rresolv(struct icb_session *is, struct sockaddr *sa)
{
struct async *as;
if (!dodns)
return;
if (verbose)
icbd_log(is, LOG_DEBUG, "resolving: %s", is->host);
as = getnameinfo_async(sa, sa->sa_len, is->hostname,
sizeof is->hostname, NULL, 0, NI_NOFQDN, NULL);
async_run_event(as, dns_done, is);
}
/* Generic libevent glue for asr */
struct async_event {
struct async *async;
struct event ev;
void (*callback)(int, struct async_res *, void *);
void *arg;
};
void async_event_dispatch(int, short, void *);
struct async_event *
async_run_event(struct async * async,
void (*cb)(int, struct async_res *, void *), void *arg)
{
struct async_event *aev;
struct timeval tv;
aev = calloc(1, sizeof *aev);
if (aev == NULL)
return (NULL);
aev->async = async;
aev->callback = cb;
aev->arg = arg;
tv.tv_sec = 0;
tv.tv_usec = 0;
evtimer_set(&aev->ev, async_event_dispatch, aev);
evtimer_add(&aev->ev, &tv);
return (aev);
}
void
async_event_dispatch(int fd __attribute__((__unused__)),
short ev __attribute__((__unused__)), void *arg)
{
struct async_event *aev = arg;
struct async_res ar;
int r;
struct timeval tv;
while ((r = asr_async_run(aev->async, &ar)) == ASYNC_YIELD)
aev->callback(r, &ar, aev->arg);
event_del(&aev->ev);
if (r == ASYNC_COND) {
event_set(&aev->ev, ar.ar_fd,
ar.ar_cond == ASYNC_READ ? EV_READ : EV_WRITE,
async_event_dispatch, aev);
tv.tv_sec = ar.ar_timeout / 1000;
tv.tv_usec = (ar.ar_timeout % 1000) * 1000;
event_add(&aev->ev, &tv);
} else { /* ASYNC_DONE */
aev->callback(r, &ar, aev->arg);
free(aev);
}
}