usr.sbin/dntpd/socket.c

   1 /*
   2  * Copyright (c) 2005 The DragonFly Project.  All rights reserved.
   3  *
   4  * This code is derived from software contributed to The DragonFly Project
   5  * by Matthew Dillon <dillon@backplane.com>
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  *
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in
  15  *    the documentation and/or other materials provided with the
  16  *    distribution.
  17  * 3. Neither the name of The DragonFly Project nor the names of its
  18  *    contributors may be used to endorse or promote products derived
  19  *    from this software without specific, prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  22  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  23  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  24  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
  25  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  26  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
  27  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  28  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
  29  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  30  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  31  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  *
  34  * $DragonFly: src/usr.sbin/dntpd/socket.c,v 1.4 2007/06/25 21:33:36 dillon Exp $
  35  */
  36
  37 #include "defs.h"
  38
  39 int
  40 udp_socket(const char *target, int port, struct sockaddr *sam,
  41            dns_error_policy_t dns_error_policy)
  42 {
  43     struct addrinfo hints, *res, *res0;
  44     char servname[128];
  45     const char *cause = NULL;
  46     int error;
  47     int fd;
  48     int tos;
  49
  50     memset(&hints, 0, sizeof(hints));
  51     hints.ai_family = family;
  52     hints.ai_socktype = SOCK_DGRAM;
  53     snprintf(servname, sizeof(servname), "%d", port);
  54     error = getaddrinfo(target, servname, &hints, &res0);
  55     if (error) {
  56         if (dns_error_policy == LOG_DNS_ERROR)
  57             logerr("getaddrinfo (%s) init error: %s", target,
  58                 gai_strerror(error));
  59         return(-1);
  60     }
  61
  62     fd = -1;
  63     for (res = res0; res; res = res->ai_next) {
  64         fd = socket(res->ai_family, res->ai_socktype,
  65         res->ai_protocol);
  66         if (fd < 0) {
  67            cause = "socket";
  68            continue;
  69         }
  70
  71         if (fcntl(fd, F_SETFL, O_NONBLOCK) < 0) {
  72             logerr("%s: unable to set non-blocking mode", target);
  73             close(fd);
  74             fd = -1;
  75             continue;
  76         }
  77
  78         if (connect(fd, res->ai_addr, res->ai_addrlen) < 0) {
  79            cause = "connect";
  80            close(fd);
  81            fd = -1;
  82            continue;
  83         }
  84
  85         break;  /* okay we got one */
  86     }
  87
  88     if (fd < 0) {
  89         logerr("Unable to establish a connection with %s: %s", target, cause);
  90         return(-1);
  91     }
  92     memcpy(sam, res->ai_addr, res->ai_addr->sa_len);
  93     freeaddrinfo(res0);
  94
  95 #ifdef IPTOS_LOWDELAY
  96     tos = IPTOS_LOWDELAY;
  97     setsockopt(fd, IPPROTO_IP, IP_TOS, &tos, sizeof(tos));
  98 #endif
  99 #if 0
 100 #ifdef IP_PORTRANGE
 101     tos = IP_PORTRANGE_HIGH;
 102     setsockopt(fd, IPPROTO_IP, IP_PORTRANGE, &tos, sizeof(tos));
 103 #endif
 104 #endif
 105     return(fd);
 106 }