[thirdparty/dhcp.git] / common / upf.c

/* upf.c

   Ultrix PacketFilter interface code. */

/*
 * Copyright (c) 2004-2017 by Internet Systems Consortium, Inc. ("ISC")
 * Copyright (c) 1996-2003 by Internet Software Consortium
 *
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC 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.
 *
 *   Internet Systems Consortium, Inc.
 *   950 Charter Street
 *   Redwood City, CA 94063
 *   <info@isc.org>
 *   https://www.isc.org/
 *
 */

#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++) {
		/* %Audit% Cannot exceed 36 bytes. %2004.06.17,Safe% */
		sprintf(filename, "/dev/pf/pfilt%d", b);

		sock = open (filename, O_RDWR, 0);
		if (sock < 0) {
			if (errno == EBUSY) {
				continue;
			} else {
				log_fatal ("Can't find free upf: %m");
			}
		} else {
			break;
		}
	}

	/* Set the UPF device to point at this interface. */
	if (ioctl (sock, EIOCSETIF, info -> ifp) < 0)
		log_fatal ("Can't attach interface %s to upf device %s: %m",
		       info -> name, filename);

	/* Get the hardware address. */
	if (ioctl (sock, EIOCDEVP, &param) < 0)
		log_fatal ("Can't get interface %s hardware address: %m",
		       info -> name);

	/* We only know how to do ethernet. */
	if (param.end_dev_type != ENDT_10MB)	
		log_fatal ("Invalid device type on network interface %s: %d",
		       info -> name, param.end_dev_type);

	if (param.end_addr_len != 6)
		log_fatal ("Invalid hardware address length on %s: %d",
		       info -> name, param.end_addr_len);

	info -> hw_address.hlen = 7;
	info -> hw_address.hbuf [0] = ARPHRD_ETHER;
	memcpy (&info -> hw_address.hbuf [1], 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)
		log_info ("Sending on   UPF/%s/%s%s%s",
		      info -> name,
		      print_hw_addr (info -> hw_address.hbuf [0],
				     info -> hw_address.hlen - 1,
				     &info -> hw_address.hbuf [1]),
		      (info -> shared_network ? "/" : ""),
		      (info -> shared_network ?
		       info -> shared_network -> name : ""));
}

void if_deregister_send (info)
	struct interface_info *info;
{
#ifndef USE_UPF_RECEIVE
	close (info -> wfdesc);
#endif
	info -> wfdesc = -1;
        if (!quiet_interface_discovery)
		log_info ("Disabling output on UPF/%s/%s%s%s",
		      info -> name,
		      print_hw_addr (info -> hw_address.hbuf [0],
				     info -> hw_address.hlen - 1,
				     &info -> hw_address.hbuf [1]),
		      (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)
		log_fatal ("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)
		log_fatal ("Can't clear pfilt bits: %m");

	/* Set the ENBATCH and ENCOPYALL bits... */
	bits = ENBATCH | ENCOPYALL;
	if (ioctl (info -> rfdesc, EIOCMBIS, &bits) < 0)
		log_fatal ("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)
		log_fatal ("Can't install packet filter program: %m");
        if (!quiet_interface_discovery)
		log_info ("Listening on UPF/%s/%s%s%s",
		      info -> name,
		      print_hw_addr (info -> hw_address.hbuf [0],
				     info -> hw_address.hlen - 1,
				     &info -> hw_address.hbuf [1]),
		      (info -> shared_network ? "/" : ""),
		      (info -> shared_network ?
		       info -> shared_network -> name : ""));
}

void if_deregister_receive (info)
	struct interface_info *info;
{
	close (info -> rfdesc);
	info -> rfdesc = -1;
        if (!quiet_interface_discovery)
		log_info ("Disabling input on UPF/%s/%s%s%s",
		      info -> name,
		      print_hw_addr (info -> hw_address.hbuf [0],
				     info -> hw_address.hlen - 1,
				     &info -> hw_address.hbuf [1]),
		      (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;
{
	unsigned hbufp = 0, ibufp = 0;
	double hw [4];
	double ip [32];
	struct iovec iov [3];
	int result;
	int fudge;

	if (!strcmp (interface -> name, "fallback"))
		return send_fallback (interface, packet, raw,
				      len, from, to, hto);

	if (hto == NULL && interface->anycast_mac_addr.hlen)
		hto = &interface->anycast_mac_addr;

	/* Assemble the headers... */
	assemble_hw_header (interface, (unsigned char *)hw, &hbufp, hto);
	assemble_udp_ip_header (interface,
				(unsigned char *)ip, &ibufp, from.s_addr,
				to -> sin_addr.s_addr, to -> sin_port,
				(unsigned char *)raw, len);

	/* Fire it off */
	iov [0].iov_base = ((char *)hw);
	iov [0].iov_len = hbufp;
	iov [1].iov_base = ((char *)ip);
	iov [1].iov_len = ibufp;
	iov [2].iov_base = (char *)raw;
	iov [2].iov_len = len;

	result = writev(interface -> wfdesc, iov, 3);
	if (result < 0)
		log_error ("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;
	unsigned paylen;

	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, length, &paylen, 1);

	/* If the IP or UDP checksum was bad, skip the packet... */
	if (offset < 0)
		return 0;

	bufix += offset;
	length -= offset;

	if (length < paylen)
		log_fatal("Internal inconsistency at %s:%d.", MDL);

	/* Copy out the data in the packet... */
	memcpy (buf, &ibuf[bufix], paylen);
	return paylen;
}

int can_unicast_without_arp (ip)
	struct interface_info *ip;
{
	return 1;
}

int can_receive_unicast_unconfigured (ip)
	struct interface_info *ip;
{
	return 1;
}

int supports_multiple_interfaces (ip)
	struct interface_info *ip;
{
	return 1;
}

void maybe_setup_fallback ()
{
	isc_result_t status;
	struct interface_info *fbi = (struct interface_info *)0;
	if (setup_fallback (&fbi, MDL)) {
		if_register_fallback (fbi);
		status = omapi_register_io_object ((omapi_object_t *)fbi,
						   if_readsocket, 0,
						   fallback_discard, 0, 0);
		if (status != ISC_R_SUCCESS)
			log_fatal ("Can't register I/O handle for %s: %s",
				   fbi -> name, isc_result_totext (status));
		interface_dereference (&fbi, MDL);
	}
}
#endif
Commit	Line	Data
179f54ab TL	1	/* upf.c
179f54ab TL	2
2d1b06e0	3	Ultrix PacketFilter interface code. */
179f54ab TL	4
179f54ab TL	5	/*
7512d88b	6	* Copyright (c) 2004-2017 by Internet Systems Consortium, Inc. ("ISC")
98311e4b	7	* Copyright (c) 1996-2003 by Internet Software Consortium
179f54ab	8	*
7512d88b TM	9	* This Source Code Form is subject to the terms of the Mozilla Public
	10	* License, v. 2.0. If a copy of the MPL was not distributed with this
	11	* file, You can obtain one at http://mozilla.org/MPL/2.0/.
179f54ab	12	*
98311e4b DH	13	* THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
	14	* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
	15	* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR
	16	* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
	17	* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
	18	* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
	19	* OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
179f54ab	20	*
98311e4b DH	21	* Internet Systems Consortium, Inc.
	22	* 950 Charter Street
	23	* Redwood City, CA 94063
	24	* <info@isc.org>
2c85ac9b	25	* https://www.isc.org/
49733f31	26	*
179f54ab TL	27	*/
179f54ab TL	28
179f54ab TL	29	#include "dhcpd.h"
	30	#if defined (USE_UPF_SEND) \|\| defined (USE_UPF_RECEIVE)
	31	#include <sys/ioctl.h>
	32	#include <sys/uio.h>
	33
	34	#include <net/pfilt.h>
	35	#include <netinet/in_systm.h>
	36	#include "includes/netinet/ip.h"
	37	#include "includes/netinet/udp.h"
	38	#include "includes/netinet/if_ether.h"
	39
	40	/* Reinitializes the specified interface after an address change. This
	41	is not required for packet-filter APIs. */
	42
	43	#ifdef USE_UPF_SEND
	44	void if_reinitialize_send (info)
	45	struct interface_info *info;
	46	{
	47	}
	48	#endif
	49
	50	#ifdef USE_UPF_RECEIVE
	51	void if_reinitialize_receive (info)
	52	struct interface_info *info;
	53	{
	54	}
	55	#endif
	56
	57	/* Called by get_interface_list for each interface that's discovered.
	58	Opens a packet filter for each interface and adds it to the select
	59	mask. */
	60
	61	int if_register_upf (info)
	62	struct interface_info *info;
	63	{
	64	int sock;
	65	char filename[50];
	66	int b;
	67	struct endevp param;
	68
	69	/* Open a UPF device */
	70	for (b = 0; 1; b++) {
98311e4b	71	/* %Audit% Cannot exceed 36 bytes. %2004.06.17,Safe% */
179f54ab	72	sprintf(filename, "/dev/pf/pfilt%d", b);
98311e4b	73
179f54ab TL	74	sock = open (filename, O_RDWR, 0);
	75	if (sock < 0) {
	76	if (errno == EBUSY) {
	77	continue;
	78	} else {
8ae2d595	79	log_fatal ("Can't find free upf: %m");
179f54ab TL	80	}
	81	} else {
	82	break;
	83	}
	84	}
	85
	86	/* Set the UPF device to point at this interface. */
	87	if (ioctl (sock, EIOCSETIF, info -> ifp) < 0)
8ae2d595	88	log_fatal ("Can't attach interface %s to upf device %s: %m",
179f54ab TL	89	info -> name, filename);
	90
	91	/* Get the hardware address. */
	92	if (ioctl (sock, EIOCDEVP, &param) < 0)
8ae2d595	93	log_fatal ("Can't get interface %s hardware address: %m",
179f54ab TL	94	info -> name);
	95
	96	/* We only know how to do ethernet. */
	97	if (param.end_dev_type != ENDT_10MB)
8ae2d595	98	log_fatal ("Invalid device type on network interface %s: %d",
179f54ab TL	99	info -> name, param.end_dev_type);
	100
	101	if (param.end_addr_len != 6)
8ae2d595	102	log_fatal ("Invalid hardware address length on %s: %d",
179f54ab TL	103	info -> name, param.end_addr_len);
179f54ab TL	104
218eee75 TL	105	info -> hw_address.hlen = 7;
	106	info -> hw_address.hbuf [0] = ARPHRD_ETHER;
	107	memcpy (&info -> hw_address.hbuf [1], param.end_addr, 6);
179f54ab TL	108
	109	return sock;
	110	}
	111	#endif /* USE_UPF_SEND \|\| USE_UPF_RECEIVE */
	112
	113	#ifdef USE_UPF_SEND
	114	void if_register_send (info)
	115	struct interface_info *info;
	116	{
	117	/* If we're using the upf API for sending and receiving,
	118	we don't need to register this interface twice. */
	119	#ifndef USE_UPF_RECEIVE
	120	info -> wfdesc = if_register_upf (info, interface);
	121	#else
	122	info -> wfdesc = info -> rfdesc;
	123	#endif
3648a2a1	124	if (!quiet_interface_discovery)
74f45f96	125	log_info ("Sending on UPF/%s/%s%s%s",
3648a2a1	126	info -> name,
218eee75 TL	127	print_hw_addr (info -> hw_address.hbuf [0],
	128	info -> hw_address.hlen - 1,
	129	&info -> hw_address.hbuf [1]),
74f45f96	130	(info -> shared_network ? "/" : ""),
3648a2a1	131	(info -> shared_network ?
74f45f96	132	info -> shared_network -> name : ""));
179f54ab	133	}
7203e8ee TL	134
	135	void if_deregister_send (info)
	136	struct interface_info *info;
	137	{
	138	#ifndef USE_UPF_RECEIVE
	139	close (info -> wfdesc);
	140	#endif
	141	info -> wfdesc = -1;
	142	if (!quiet_interface_discovery)
	143	log_info ("Disabling output on UPF/%s/%s%s%s",
	144	info -> name,
	145	print_hw_addr (info -> hw_address.hbuf [0],
	146	info -> hw_address.hlen - 1,
	147	&info -> hw_address.hbuf [1]),
	148	(info -> shared_network ? "/" : ""),
	149	(info -> shared_network ?
	150	info -> shared_network -> name : ""));
	151	}
179f54ab TL	152	#endif /* USE_UPF_SEND */
	153
	154	#ifdef USE_UPF_RECEIVE
	155	/* Packet filter program...
	156	XXX Changes to the filter program may require changes to the constant
	157	offsets used in if_register_send to patch the UPF program! XXX */
	158
	159
	160	void if_register_receive (info)
	161	struct interface_info *info;
	162	{
	163	int flag = 1;
	164	u_int32_t addr;
	165	struct enfilter pf;
	166	u_int32_t bits;
	167
	168	/* Open a UPF device and hang it on this interface... */
	169	info -> rfdesc = if_register_upf (info);
	170
	171	/* Allow the copyall flag to be set... */
	172	if (ioctl(info -> rfdesc, EIOCALLOWCOPYALL, &flag) < 0)
8ae2d595	173	log_fatal ("Can't set ALLOWCOPYALL: %m");
179f54ab TL	174
	175	/* Clear all the packet filter mode bits first... */
	176	flag = (ENHOLDSIG \| ENBATCH \| ENTSTAMP \| ENPROMISC \|
	177	ENNONEXCL \| ENCOPYALL);
	178	if (ioctl (info -> rfdesc, EIOCMBIC, &flag) < 0)
8ae2d595	179	log_fatal ("Can't clear pfilt bits: %m");
179f54ab TL	180
	181	/* Set the ENBATCH and ENCOPYALL bits... */
	182	bits = ENBATCH \| ENCOPYALL;
	183	if (ioctl (info -> rfdesc, EIOCMBIS, &bits) < 0)
8ae2d595	184	log_fatal ("Can't set ENBATCH\|ENCOPYALL: %m");
179f54ab TL	185
	186	/* Set up the UPF filter program. */
	187	/* XXX Unlike the BPF filter program, this one won't work if the
	188	XXX IP packet is fragmented or if there are options on the IP
	189	XXX header. */
	190	pf.enf_Priority = 0;
	191	pf.enf_FilterLen = 0;
	192
	193	pf.enf_Filter [pf.enf_FilterLen++] = ENF_PUSHWORD + 6;
	194	pf.enf_Filter [pf.enf_FilterLen++] = ENF_PUSHLIT + ENF_CAND;
	195	pf.enf_Filter [pf.enf_FilterLen++] = htons (ETHERTYPE_IP);
	196	pf.enf_Filter [pf.enf_FilterLen++] = ENF_PUSHLIT;
	197	pf.enf_Filter [pf.enf_FilterLen++] = htons (IPPROTO_UDP);
	198	pf.enf_Filter [pf.enf_FilterLen++] = ENF_PUSHWORD + 11;
	199	pf.enf_Filter [pf.enf_FilterLen++] = ENF_PUSHLIT + ENF_AND;
	200	pf.enf_Filter [pf.enf_FilterLen++] = htons (0xFF);
	201	pf.enf_Filter [pf.enf_FilterLen++] = ENF_CAND;
	202	pf.enf_Filter [pf.enf_FilterLen++] = ENF_PUSHWORD + 18;
	203	pf.enf_Filter [pf.enf_FilterLen++] = ENF_PUSHLIT + ENF_CAND;
	204	pf.enf_Filter [pf.enf_FilterLen++] = local_port;
	205
	206	if (ioctl (info -> rfdesc, EIOCSETF, &pf) < 0)
8ae2d595	207	log_fatal ("Can't install packet filter program: %m");
3648a2a1	208	if (!quiet_interface_discovery)
74f45f96	209	log_info ("Listening on UPF/%s/%s%s%s",
3648a2a1	210	info -> name,
218eee75 TL	211	print_hw_addr (info -> hw_address.hbuf [0],
	212	info -> hw_address.hlen - 1,
	213	&info -> hw_address.hbuf [1]),
74f45f96	214	(info -> shared_network ? "/" : ""),
3648a2a1	215	(info -> shared_network ?
74f45f96	216	info -> shared_network -> name : ""));
179f54ab	217	}
7203e8ee TL	218
	219	void if_deregister_receive (info)
	220	struct interface_info *info;
	221	{
	222	close (info -> rfdesc);
	223	info -> rfdesc = -1;
	224	if (!quiet_interface_discovery)
	225	log_info ("Disabling input on UPF/%s/%s%s%s",
	226	info -> name,
	227	print_hw_addr (info -> hw_address.hbuf [0],
	228	info -> hw_address.hlen - 1,
	229	&info -> hw_address.hbuf [1]),
	230	(info -> shared_network ? "/" : ""),
	231	(info -> shared_network ?
	232	info -> shared_network -> name : ""));
	233	}
179f54ab TL	234	#endif /* USE_UPF_RECEIVE */
	235
	236	#ifdef USE_UPF_SEND
4595a58c	237	ssize_t send_packet (interface, packet, raw, len, from, to, hto)
179f54ab TL	238	struct interface_info *interface;
	239	struct packet *packet;
	240	struct dhcp_packet *raw;
	241	size_t len;
	242	struct in_addr from;
	243	struct sockaddr_in *to;
	244	struct hardware *hto;
	245	{
6ceb9118 TL	246	unsigned hbufp = 0, ibufp = 0;
	247	double hw [4];
	248	double ip [32];
	249	struct iovec iov [3];
74f45f96	250	int result;
6ceb9118	251	int fudge;
179f54ab	252
d2bc90bd TL	253	if (!strcmp (interface -> name, "fallback"))
	254	return send_fallback (interface, packet, raw,
	255	len, from, to, hto);
	256
0829d595 DH	257	if (hto == NULL && interface->anycast_mac_addr.hlen)
	258	hto = &interface->anycast_mac_addr;
	259
179f54ab	260	/* Assemble the headers... */
6ceb9118 TL	261	assemble_hw_header (interface, (unsigned char *)hw, &hbufp, hto);
	262	assemble_udp_ip_header (interface,
	263	(unsigned char *)ip, &ibufp, from.s_addr,
179f54ab TL	264	to -> sin_addr.s_addr, to -> sin_port,
	265	(unsigned char *)raw, len);
	266
	267	/* Fire it off */
6ceb9118 TL	268	iov [0].iov_base = ((char *)hw);
	269	iov [0].iov_len = hbufp;
	270	iov [1].iov_base = ((char *)ip);
	271	iov [1].iov_len = ibufp;
	272	iov [2].iov_base = (char *)raw;
	273	iov [2].iov_len = len;
	274
	275	result = writev(interface -> wfdesc, iov, 3);
74f45f96	276	if (result < 0)
c5b0f529	277	log_error ("send_packet: %m");
74f45f96	278	return result;
179f54ab TL	279	}
	280	#endif /* USE_UPF_SEND */
	281
	282	#ifdef USE_UPF_RECEIVE
4595a58c	283	ssize_t receive_packet (interface, buf, len, from, hfrom)
179f54ab TL	284	struct interface_info *interface;
	285	unsigned char *buf;
	286	size_t len;
	287	struct sockaddr_in *from;
	288	struct hardware *hfrom;
	289	{
	290	int nread;
	291	int length = 0;
	292	int offset = 0;
	293	unsigned char ibuf [1500 + sizeof (struct enstamp)];
	294	int bufix = 0;
83c0372e	295	unsigned paylen;
179f54ab TL	296
	297	length = read (interface -> rfdesc, ibuf, sizeof ibuf);
	298	if (length <= 0)
	299	return length;
	300
	301	bufix = sizeof (struct enstamp);
	302	/* Decode the physical header... */
	303	offset = decode_hw_header (interface, ibuf, bufix, hfrom);
	304
	305	/* If a physical layer checksum failed (dunno of any
	306	physical layer that supports this, but WTH), skip this
	307	packet. */
	308	if (offset < 0) {
	309	return 0;
	310	}
	311
	312	bufix += offset;
	313	length -= offset;
	314
	315	/* Decode the IP and UDP headers... */
	316	offset = decode_udp_ip_header (interface, ibuf, bufix,
7ff6ae5a	317	from, length, &paylen, 1);
179f54ab TL	318
	319	/* If the IP or UDP checksum was bad, skip the packet... */
	320	if (offset < 0)
	321	return 0;
	322
	323	bufix += offset;
	324	length -= offset;
	325
83c0372e EH	326	if (length < paylen)
	327	log_fatal("Internal inconsistency at %s:%d.", MDL);
	328
179f54ab	329	/* Copy out the data in the packet... */
83c0372e EH	330	memcpy (buf, &ibuf[bufix], paylen);
83c0372e EH	331	return paylen;
179f54ab	332	}
d2bc90bd	333
21d21e91 TL	334	int can_unicast_without_arp (ip)
21d21e91 TL	335	struct interface_info *ip;
d2bc90bd TL	336	{
	337	return 1;
	338	}
	339
21d21e91 TL	340	int can_receive_unicast_unconfigured (ip)
21d21e91 TL	341	struct interface_info *ip;
b547818b TL	342	{
	343	return 1;
	344	}
	345
5cefe5e5 TL	346	int supports_multiple_interfaces (ip)
	347	struct interface_info *ip;
	348	{
	349	return 1;
	350	}
	351
d2bc90bd TL	352	void maybe_setup_fallback ()
d2bc90bd TL	353	{
acc21512	354	isc_result_t status;
20916cae TL	355	struct interface_info fbi = (struct interface_info )0;
20916cae TL	356	if (setup_fallback (&fbi, MDL)) {
d2bc90bd	357	if_register_fallback (fbi);
e92653f1	358	status = omapi_register_io_object ((omapi_object_t *)fbi,
acc21512 TL	359	if_readsocket, 0,
	360	fallback_discard, 0, 0);
	361	if (status != ISC_R_SUCCESS)
	362	log_fatal ("Can't register I/O handle for %s: %s",
	363	fbi -> name, isc_result_totext (status));
68e1f67a	364	interface_dereference (&fbi, MDL);
d2bc90bd TL	365	}
d2bc90bd TL	366	}
179f54ab	367	#endif