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/* socket.c
BSD socket interface code... */
/*
* Copyright (c) 1995, 1996 The Internet Software Consortium.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of The Internet Software Consortium nor the names
* of its contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE INTERNET SOFTWARE CONSORTIUM AND
* CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE INTERNET SOFTWARE CONSORTIUM OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* This software has been written for the Internet Software Consortium
* by Ted Lemon <mellon@fugue.com> in cooperation with Vixie
* Enterprises. To learn more about the Internet Software Consortium,
* see ``http://www.vix.com/isc''. To learn more about Vixie
* Enterprises, see ``http://www.vix.com''.
*/
#ifndef lint
static char copyright[] =
"@(#) Copyright (c) 1995, 1996 The Internet Software Consortium. All rights reserved.\n";
#endif /* not lint */
#include "dhcpd.h"
#ifdef USE_SOCKET_FALLBACK
# define USE_SOCKET_SEND
# define if_register_send if_register_fallback
# define send_packet send_fallback
#endif
#if defined (USE_SOCKET_SEND) || defined (USE_SOCKET_RECEIVE)
/* Generic interface registration routine... */
int if_register_socket (info, interface)
struct interface_info *info;
struct ifreq *interface;
{
struct sockaddr_in name;
int sock;
struct socklist *tmp;
int flag;
static int once = 0;
/* Make sure only one interface is registered. */
if (once)
error ("The standard socket API can only support %s%s%s%s%s",
"hosts with a single network interface. If you must ",
"run dhcpd on a host with multiple interfaces, ",
"you must compile in BPF or NIT support. If neither ",
"option is supported on your system, please let us ",
"know.");
/* Technically, we need to know what interface every packet
comes in on, which means that we can only operate on a
machine with a single interface configured. However,
we generally don't expect to get broadcast packets on
point-to-point interfaces, so we can bend the rules a bit
and not count them. This won't allow DHCP-over-PPP,
but it's probably right in a lot of cases, and the issue
will have to be revisited when DHCP-over-PPP support is
done. Currently we determine whether an interface is
point-to-point by seeing if it has a link-level address.
This only works on 4.4BSD and derivative networking. */
#ifdef AF_LINK
if (info -> hw_address.hlen) /* XXX */
#endif
once = 1;
/* Set up the address we're going to bind to. */
name.sin_family = AF_INET;
name.sin_port = server_port;
name.sin_addr.s_addr = INADDR_ANY;
memset (name.sin_zero, 0, sizeof (name.sin_zero));
/* Make a socket... */
if ((sock = socket (AF_INET, SOCK_DGRAM, IPPROTO_UDP)) < 0)
error ("Can't create dhcp socket: %m");
/* Set the REUSEADDR option so that we don't fail to start if
we're being restarted. */
flag = 1;
if (setsockopt (sock, SOL_SOCKET, SO_REUSEADDR,
(char *)&flag, sizeof flag) < 0)
error ("Can't set SO_REUSEADDR option on dhcp socket: %m");
/* Set the BROADCAST option so that we can broadcast DHCP responses. */
if (setsockopt (sock, SOL_SOCKET, SO_BROADCAST,
(char *)&flag, sizeof flag) < 0)
error ("Can't set SO_BROADCAST option on dhcp socket: %m");
/* Bind the socket to this interface's IP address. */
if (bind (sock, (struct sockaddr *)&name, sizeof name) < 0)
error ("Can't bind to dhcp address: %m");
return sock;
}
#endif /* USE_SOCKET_SEND || USE_SOCKET_RECEIVE */
#ifdef USE_SOCKET_SEND
void if_register_send (info, interface)
struct interface_info *info;
struct ifreq *interface;
{
#ifndef USE_SOCKET_RECEIVE
info -> wfdesc = if_register_socket (info, interface);
#else
info -> wfdesc = info -> rfdesc;
#endif
note ("Sending on Socket/%s/%s",
info -> name,
(info -> shared_network ?
info -> shared_network -> name : "unattached"));
}
#endif /* USE_SOCKET_SEND */
#ifdef USE_SOCKET_RECEIVE
void if_register_receive (info, interface)
struct interface_info *info;
struct ifreq *interface;
{
/* If we're using the socket API for sending and receiving,
we don't need to register this interface twice. */
info -> rfdesc = if_register_socket (info, interface);
note ("Listening on Socket/%s/%s",
info -> name,
(info -> shared_network ?
info -> shared_network -> name : "unattached"));
}
#endif /* USE_SOCKET_RECEIVE */
#ifdef USE_SOCKET_SEND
size_t send_packet (interface, packet, raw, len, from, to, hto)
struct interface_info *interface;
struct packet *packet;
struct dhcp_packet *raw;
size_t len;
struct in_addr from;
struct sockaddr_in *to;
struct hardware *hto;
{
return sendto (interface -> wfdesc, (char *)raw, len, 0,
(struct sockaddr *)to, sizeof *to);
}
#endif /* USE_SOCKET_SEND */
#ifdef USE_SOCKET_RECEIVE
size_t receive_packet (interface, buf, len, from, hfrom)
struct interface_info *interface;
unsigned char *buf;
size_t len;
struct sockaddr_in *from;
struct hardware *hfrom;
{
int flen = sizeof *from;
return recvfrom (interface -> rfdesc, buf, len, 0,
(struct sockaddr *)from, &flen);
}
#endif /* USE_SOCKET_RECEIVE */
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