/*      $OpenBSD: ntp_msg.c,v 1.22 2016/09/03 11:52:06 reyk Exp $ */

/*
 * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
 * Copyright (c) 2004 Alexander Guy <alexander.guy@andern.org>
 *
 * 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 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 <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>

#include "ntpd.h"

int
ntp_getmsg(struct sockaddr *sa, char *p, ssize_t len, struct ntp_msg *msg)
{
        if (len != NTP_MSGSIZE_NOAUTH && len != NTP_MSGSIZE) {
                log_debug("malformed packet received from %s",
                    log_sockaddr(sa));
                return (-1);
        }

        memcpy(msg, p, sizeof(*msg));

        return (0);
}

int
ntp_sendmsg(int fd, struct sockaddr *sa, struct ntp_msg *msg)
{
        socklen_t       sa_len;
        ssize_t         n;

        if (sa != NULL)
                sa_len = SA_LEN(sa);
        else
                sa_len = 0;

        n = sendto(fd, msg, sizeof(*msg), 0, sa, sa_len);
        if (n == -1) {
                if (errno == ENOBUFS || errno == EHOSTUNREACH ||
                    errno == ENETDOWN || errno == EHOSTDOWN) {
                        /* logging is futile */
                        return (-1);
                }
                log_warn("sendto");
                return (-1);
        }

        if (n != sizeof(*msg)) {
                log_warnx("ntp_sendmsg: only %zd of %zu bytes sent", n,
                    sizeof(*msg));
                return (-1);
        }

        return (0);
}