331 lines
9.6 KiB
C
331 lines
9.6 KiB
C
/* upf.c
|
|
|
|
Ultrix PacketFilter interface code. */
|
|
|
|
/*
|
|
* Copyright (c) 1995, 1996, 1997, 1998, 1999
|
|
* 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[] =
|
|
"$Id: upf.c,v 1.3.2.5 1999/03/29 22:07:13 mellon Exp $ Copyright (c) 1995, 1996, 1997, 1998, 1999 The Internet Software Consortium. All rights reserved.\n";
|
|
#endif /* not lint */
|
|
|
|
#include "dhcpd.h"
|
|
#if defined (USE_UPF_SEND) || defined (USE_UPF_RECEIVE)
|
|
#include <sys/ioctl.h>
|
|
#include <sys/uio.h>
|
|
|
|
#include <net/pfilt.h>
|
|
#include <netinet/in_systm.h>
|
|
#include "includes/netinet/ip.h"
|
|
#include "includes/netinet/udp.h"
|
|
#include "includes/netinet/if_ether.h"
|
|
|
|
/* Reinitializes the specified interface after an address change. This
|
|
is not required for packet-filter APIs. */
|
|
|
|
#ifdef USE_UPF_SEND
|
|
void if_reinitialize_send (info)
|
|
struct interface_info *info;
|
|
{
|
|
}
|
|
#endif
|
|
|
|
#ifdef USE_UPF_RECEIVE
|
|
void if_reinitialize_receive (info)
|
|
struct interface_info *info;
|
|
{
|
|
}
|
|
#endif
|
|
|
|
/* Called by get_interface_list for each interface that's discovered.
|
|
Opens a packet filter for each interface and adds it to the select
|
|
mask. */
|
|
|
|
int if_register_upf (info)
|
|
struct interface_info *info;
|
|
{
|
|
int sock;
|
|
char filename[50];
|
|
int b;
|
|
struct endevp param;
|
|
|
|
/* Open a UPF device */
|
|
for (b = 0; 1; b++) {
|
|
#ifndef NO_SNPRINTF
|
|
snprintf(filename, sizeof(filename), "/dev/pf/pfilt%d", b);
|
|
#else
|
|
sprintf(filename, "/dev/pf/pfilt%d", b);
|
|
#endif
|
|
sock = open (filename, O_RDWR, 0);
|
|
if (sock < 0) {
|
|
if (errno == EBUSY) {
|
|
continue;
|
|
} else {
|
|
error ("Can't find free upf: %m");
|
|
}
|
|
} else {
|
|
break;
|
|
}
|
|
}
|
|
|
|
/* Set the UPF device to point at this interface. */
|
|
if (ioctl (sock, EIOCSETIF, info -> ifp) < 0)
|
|
error ("Can't attach interface %s to upf device %s: %m",
|
|
info -> name, filename);
|
|
|
|
/* Get the hardware address. */
|
|
if (ioctl (sock, EIOCDEVP, ¶m) < 0)
|
|
error ("Can't get interface %s hardware address: %m",
|
|
info -> name);
|
|
|
|
/* We only know how to do ethernet. */
|
|
if (param.end_dev_type != ENDT_10MB)
|
|
error ("Invalid device type on network interface %s: %d",
|
|
info -> name, param.end_dev_type);
|
|
|
|
if (param.end_addr_len != 6)
|
|
error ("Invalid hardware address length on %s: %d",
|
|
info -> name, param.end_addr_len);
|
|
|
|
info -> hw_address.hlen = 6;
|
|
info -> hw_address.htype = ARPHRD_ETHER;
|
|
memcpy (&info -> hw_address.haddr [0], param.end_addr, 6);
|
|
|
|
return sock;
|
|
}
|
|
#endif /* USE_UPF_SEND || USE_UPF_RECEIVE */
|
|
|
|
#ifdef USE_UPF_SEND
|
|
void if_register_send (info)
|
|
struct interface_info *info;
|
|
{
|
|
/* If we're using the upf API for sending and receiving,
|
|
we don't need to register this interface twice. */
|
|
#ifndef USE_UPF_RECEIVE
|
|
info -> wfdesc = if_register_upf (info, interface);
|
|
#else
|
|
info -> wfdesc = info -> rfdesc;
|
|
#endif
|
|
if (!quiet_interface_discovery)
|
|
note ("Sending on UPF/%s/%s%s%s",
|
|
info -> name,
|
|
print_hw_addr (info -> hw_address.htype,
|
|
info -> hw_address.hlen,
|
|
info -> hw_address.haddr),
|
|
(info -> shared_network ? "/" : ""),
|
|
(info -> shared_network ?
|
|
info -> shared_network -> name : ""));
|
|
}
|
|
#endif /* USE_UPF_SEND */
|
|
|
|
#ifdef USE_UPF_RECEIVE
|
|
/* Packet filter program...
|
|
XXX Changes to the filter program may require changes to the constant
|
|
offsets used in if_register_send to patch the UPF program! XXX */
|
|
|
|
|
|
void if_register_receive (info)
|
|
struct interface_info *info;
|
|
{
|
|
int flag = 1;
|
|
u_int32_t addr;
|
|
struct enfilter pf;
|
|
u_int32_t bits;
|
|
|
|
/* Open a UPF device and hang it on this interface... */
|
|
info -> rfdesc = if_register_upf (info);
|
|
|
|
/* Allow the copyall flag to be set... */
|
|
if (ioctl(info -> rfdesc, EIOCALLOWCOPYALL, &flag) < 0)
|
|
error ("Can't set ALLOWCOPYALL: %m");
|
|
|
|
/* Clear all the packet filter mode bits first... */
|
|
flag = (ENHOLDSIG | ENBATCH | ENTSTAMP | ENPROMISC |
|
|
ENNONEXCL | ENCOPYALL);
|
|
if (ioctl (info -> rfdesc, EIOCMBIC, &flag) < 0)
|
|
error ("Can't clear pfilt bits: %m");
|
|
|
|
/* Set the ENBATCH and ENCOPYALL bits... */
|
|
bits = ENBATCH | ENCOPYALL;
|
|
if (ioctl (info -> rfdesc, EIOCMBIS, &bits) < 0)
|
|
error ("Can't set ENBATCH|ENCOPYALL: %m");
|
|
|
|
/* Set up the UPF filter program. */
|
|
/* XXX Unlike the BPF filter program, this one won't work if the
|
|
XXX IP packet is fragmented or if there are options on the IP
|
|
XXX header. */
|
|
pf.enf_Priority = 0;
|
|
pf.enf_FilterLen = 0;
|
|
|
|
pf.enf_Filter [pf.enf_FilterLen++] = ENF_PUSHWORD + 6;
|
|
pf.enf_Filter [pf.enf_FilterLen++] = ENF_PUSHLIT + ENF_CAND;
|
|
pf.enf_Filter [pf.enf_FilterLen++] = htons (ETHERTYPE_IP);
|
|
pf.enf_Filter [pf.enf_FilterLen++] = ENF_PUSHLIT;
|
|
pf.enf_Filter [pf.enf_FilterLen++] = htons (IPPROTO_UDP);
|
|
pf.enf_Filter [pf.enf_FilterLen++] = ENF_PUSHWORD + 11;
|
|
pf.enf_Filter [pf.enf_FilterLen++] = ENF_PUSHLIT + ENF_AND;
|
|
pf.enf_Filter [pf.enf_FilterLen++] = htons (0xFF);
|
|
pf.enf_Filter [pf.enf_FilterLen++] = ENF_CAND;
|
|
pf.enf_Filter [pf.enf_FilterLen++] = ENF_PUSHWORD + 18;
|
|
pf.enf_Filter [pf.enf_FilterLen++] = ENF_PUSHLIT + ENF_CAND;
|
|
pf.enf_Filter [pf.enf_FilterLen++] = local_port;
|
|
|
|
if (ioctl (info -> rfdesc, EIOCSETF, &pf) < 0)
|
|
error ("Can't install packet filter program: %m");
|
|
if (!quiet_interface_discovery)
|
|
note ("Listening on UPF/%s/%s%s%s",
|
|
info -> name,
|
|
print_hw_addr (info -> hw_address.htype,
|
|
info -> hw_address.hlen,
|
|
info -> hw_address.haddr),
|
|
(info -> shared_network ? "/" : ""),
|
|
(info -> shared_network ?
|
|
info -> shared_network -> name : ""));
|
|
}
|
|
#endif /* USE_UPF_RECEIVE */
|
|
|
|
#ifdef USE_UPF_SEND
|
|
ssize_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;
|
|
{
|
|
int bufp = 0;
|
|
unsigned char buf [256];
|
|
struct iovec iov [2];
|
|
int result;
|
|
|
|
if (!strcmp (interface -> name, "fallback"))
|
|
return send_fallback (interface, packet, raw,
|
|
len, from, to, hto);
|
|
|
|
/* Assemble the headers... */
|
|
assemble_hw_header (interface, buf, &bufp, hto);
|
|
assemble_udp_ip_header (interface, buf, &bufp, from.s_addr,
|
|
to -> sin_addr.s_addr, to -> sin_port,
|
|
(unsigned char *)raw, len);
|
|
|
|
/* Fire it off */
|
|
iov [0].iov_base = (char *)buf;
|
|
iov [0].iov_len = bufp;
|
|
iov [1].iov_base = (char *)raw;
|
|
iov [1].iov_len = len;
|
|
|
|
result = writev(interface -> wfdesc, iov, 2);
|
|
if (result < 0)
|
|
warn ("send_packet: %m");
|
|
return result;
|
|
}
|
|
#endif /* USE_UPF_SEND */
|
|
|
|
#ifdef USE_UPF_RECEIVE
|
|
ssize_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 nread;
|
|
int length = 0;
|
|
int offset = 0;
|
|
unsigned char ibuf [1500 + sizeof (struct enstamp)];
|
|
int bufix = 0;
|
|
|
|
length = read (interface -> rfdesc, ibuf, sizeof ibuf);
|
|
if (length <= 0)
|
|
return length;
|
|
|
|
bufix = sizeof (struct enstamp);
|
|
/* Decode the physical header... */
|
|
offset = decode_hw_header (interface, ibuf, bufix, hfrom);
|
|
|
|
/* If a physical layer checksum failed (dunno of any
|
|
physical layer that supports this, but WTH), skip this
|
|
packet. */
|
|
if (offset < 0) {
|
|
return 0;
|
|
}
|
|
|
|
bufix += offset;
|
|
length -= offset;
|
|
|
|
/* Decode the IP and UDP headers... */
|
|
offset = decode_udp_ip_header (interface, ibuf, bufix,
|
|
from, (unsigned char *)0, length);
|
|
|
|
/* If the IP or UDP checksum was bad, skip the packet... */
|
|
if (offset < 0)
|
|
return 0;
|
|
|
|
bufix += offset;
|
|
length -= offset;
|
|
|
|
/* Copy out the data in the packet... */
|
|
memcpy (buf, &ibuf [bufix], length);
|
|
return length;
|
|
}
|
|
|
|
int can_unicast_without_arp ()
|
|
{
|
|
return 1;
|
|
}
|
|
|
|
int can_receive_unicast_unconfigured (ip)
|
|
struct interface_info *ip;
|
|
{
|
|
return 1;
|
|
}
|
|
|
|
void maybe_setup_fallback ()
|
|
{
|
|
struct interface_info *fbi;
|
|
fbi = setup_fallback ();
|
|
if (fbi) {
|
|
if_register_fallback (fbi);
|
|
add_protocol ("fallback", fallback_interface -> wfdesc,
|
|
fallback_discard, fallback_interface);
|
|
}
|
|
}
|
|
#endif
|