1 /**	$MirOS: src/sys/arch/i386/stand/libsa/pxe.c,v 1.22 2009/10/27 13:54:28 tg Exp $ */
2 /*	$OpenBSD: pxe.c,v 1.5 2007/07/27 17:46:56 tom Exp $ */
3 /*	$NetBSD: pxe.c,v 1.5 2003/03/11 18:29:00 drochner Exp $	*/
4 
5 /*
6  * Copyright 2001 Wasabi Systems, Inc.
7  * All rights reserved.
8  *
9  * Written by Jason R. Thorpe for Wasabi Systems, Inc.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 3. All advertising materials mentioning features or use of this software
20  *    must display the following acknowledgement:
21  *	This product includes software developed for the NetBSD Project by
22  *	Wasabi Systems, Inc.
23  * 4. The name of Wasabi Systems, Inc. may not be used to endorse
24  *    or promote products derived from this software without specific prior
25  *    written permission.
26  *
27  * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND
28  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
29  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
30  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL WASABI SYSTEMS, INC
31  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
32  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
33  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
34  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
35  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
36  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
37  * POSSIBILITY OF SUCH DAMAGE.
38  */
39 
40 /*
41  * Copyright (c) 2009 Thorsten Glaser
42  * Copyright (c) 2000 Alfred Perlstein <alfred@freebsd.org>
43  * All rights reserved.
44  * Copyright (c) 2000 Paul Saab <ps@freebsd.org>
45  * All rights reserved.
46  * Copyright (c) 2000 John Baldwin <jhb@freebsd.org>
47  * All rights reserved.
48  *
49  * Redistribution and use in source and binary forms, with or without
50  * modification, are permitted provided that the following conditions
51  * are met:
52  * 1. Redistributions of source code must retain the above copyright
53  *    notice, this list of conditions and the following disclaimer.
54  * 2. Redistributions in binary form must reproduce the above copyright
55  *    notice, this list of conditions and the following disclaimer in the
56  *    documentation and/or other materials provided with the distribution.
57  *
58  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
59  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
60  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
61  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
62  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
63  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
64  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
65  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
66  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
67  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
68  * SUCH DAMAGE.
69  */
70 
71 /*
72  * Support for the Intel Preboot Execution Environment (PXE).
73  *
74  * PXE provides a UDP implementation as well as a UNDI network device
75  * driver.  UNDI is much more complicated to use than PXE UDP, so we
76  * use PXE UDP as a cheap and easy way to get PXE support.
77  */
78 
79 #include <sys/param.h>
80 #include <sys/socket.h>
81 
82 #ifdef _STANDALONE
83 #include <sys/slibkern.h>
84 #else
85 #include <string.h>
86 #endif
87 
88 #include <net/if.h>
89 
90 #include <netinet/in.h>
91 #include <netinet/if_ether.h>
92 #include <netinet/in_systm.h>
93 #include <netinet/ip.h>
94 #include <netinet/ip_var.h>
95 #include <netinet/udp.h>
96 #include <netinet/udp_var.h>
97 
98 #include <libsa.h>
99 #include <lib/libsa/net.h>
100 #include <lib/libsa/bootp.h>
101 
102 #include <stand/boot/bootarg.h>
103 
104 #include "pxeboot.h"
105 #include "pxe.h"
106 #include "pxe_netif.h"
107 
108 #define PXE_LOUD 0
109 
110 extern uint32_t pxe_bang;
111 extern uint32_t pxe_plus;
112 extern uint32_t pxecall_addr;
113 
114 int have_pxe = -1;
115 
116 int (*pxe_call)(u_int16_t);
117 int Xpxe(void);
118 
119 extern int pxecall_bang(u_int16_t);
120 extern int pxecall_plus(u_int16_t);
121 
122 extern char pxe_command_buf[256];
123 
124 BOOTPLAYER bootplayer;
125 
126 struct in_addr servip;			/* for tftp */	/* XXX init this */
127 
128 extern char *bootmac;			/* To pass to kernel */
129 
130 /* static struct btinfo_netif bi_netif; */
131 
132 /*****************************************************************************
133  * This section is a replacement for libsa/udp.c
134  *****************************************************************************/
135 
136 /* Caller must leave room for ethernet, ip, and udp headers in front!! */
137 ssize_t
pxesendudp(struct iodesc * d,void * pkt,size_t len)138 pxesendudp(struct iodesc *d, void *pkt, size_t len)
139 {
140 	t_PXENV_UDP_WRITE *uw = (void *) pxe_command_buf;
141 
142 	uw->status = 0;
143 
144 	uw->ip = d->destip.s_addr;
145 	uw->gw = gateip.s_addr;
146 	uw->src_port = d->myport;
147 	uw->dst_port = d->destport;
148 	uw->buffer_size = len;
149 	uw->buffer.segment = VTOPSEG(pkt);
150 	uw->buffer.offset = VTOPOFF(pkt);
151 
152 	pxe_call(PXENV_UDP_WRITE);
153 
154 	if (uw->status != PXENV_STATUS_SUCCESS) {
155 		/* XXX This happens a lot; it shouldn't. */
156 		if (uw->status != PXENV_STATUS_FAILURE)
157 			printf("sendudp: PXENV_UDP_WRITE failed: 0x%x\n",
158 			    uw->status);
159 		return -1;
160 	}
161 
162 	return len;
163 }
164 
165 /*
166  * Receive a UDP packet and validate it for us.
167  * Caller leaves room for the headers (Ether, IP, UDP).
168  */
169 ssize_t
pxereadudp(struct iodesc * d,void * pkt,size_t len,time_t tleft)170 pxereadudp(struct iodesc *d, void *pkt, size_t len, time_t tleft)
171 {
172 	t_PXENV_UDP_READ *ur = (void *) pxe_command_buf;
173 	struct udphdr *uh;
174 	struct ip *ip;
175 
176 	uh = (struct udphdr *)pkt - 1;
177 	ip = (struct ip *)uh - 1;
178 
179 	bzero(ur, sizeof(*ur));
180 
181 	ur->dest_ip = d->myip.s_addr;
182 	ur->d_port = d->myport;
183 	ur->buffer_size = len;
184 	ur->buffer.segment = VTOPSEG(pkt);
185 	ur->buffer.offset = VTOPOFF(pkt);
186 
187 	/* XXX Timeout unused. */
188 
189 	pxe_call(PXENV_UDP_READ);
190 
191 	if (ur->status != PXENV_STATUS_SUCCESS) {
192 		/* XXX This happens a lot; it shouldn't. */
193 		if (ur->status != PXENV_STATUS_FAILURE)
194 			printf("readudp: PXENV_UDP_READ_failed: 0x%x\n",
195 			    ur->status);
196 		return -1;
197 	}
198 
199 	ip->ip_src.s_addr = ur->src_ip;
200 	uh->uh_sport = ur->s_port;
201 	uh->uh_dport = d->myport;
202 
203 	return ur->buffer_size;
204 }
205 
206 /*
207  * netif layer:
208  *  open, close, shutdown: called from dev_net.c
209  *  socktodesc: called by network protocol modules
210  *
211  * We only allow one open socket.
212  */
213 
214 static struct iodesc desc;
215 
216 int
pxe_netif_open()217 pxe_netif_open()
218 {
219 	t_PXENV_UDP_OPEN *uo = (void *) pxe_command_buf;
220 
221 #ifdef NETIF_DEBUG
222 	printf("pxe_netif_open()\n");
223 #endif
224 	if (have_pxe < 0)
225 		pxe_init(0);
226 	if (!have_pxe)
227 		return (-1);
228 
229 	/* BI_ADD(&bi_netif, BTINFO_NETIF, sizeof(bi_netif)); */
230 
231 	bzero(uo, sizeof(*uo));
232 
233 	uo->src_ip = bootplayer.yip;
234 
235 	pxe_call(PXENV_UDP_OPEN);
236 
237 	if (uo->status != PXENV_STATUS_SUCCESS) {
238 		printf("\npxe_netif_open: PXENV_UDP_OPEN failed: 0x%x\n",
239 		    uo->status);
240 		return -1;
241 	}
242 
243 	bcopy(bootplayer.CAddr, desc.myea, ETHER_ADDR_LEN);
244 	bootmac = bootplayer.CAddr;
245 
246 	/*
247 	 * Since the PXE BIOS has already done DHCP, make sure we
248 	 * don't reuse any of its transaction IDs.
249 	 */
250 	desc.xid = bootplayer.ident;
251 
252 	return 0;
253 }
254 
255 void
pxe_netif_close(sock)256 pxe_netif_close(sock)
257 	int sock;
258 {
259 	t_PXENV_UDP_CLOSE *uc = (void *) pxe_command_buf;
260 
261 #ifdef NETIF_DEBUG
262 	if (sock != 0)
263 		printf("pxe_netif_close: sock=%d\n", sock);
264 #endif
265 
266 	uc->status = 0;
267 
268 	pxe_call(PXENV_UDP_CLOSE);
269 
270 	if (uc->status != PXENV_STATUS_SUCCESS)
271 		printf("pxe_netif_end: PXENV_UDP_CLOSE failed: 0x%x\n",
272 		    uc->status);
273 }
274 
275 void
pxe_netif_shutdown()276 pxe_netif_shutdown()
277 {
278 #ifdef NETIF_DEBUG
279 	printf("pxe_netif_shutdown()\n");
280 #endif
281 
282 	pxe_shutdown();
283 }
284 
285 struct iodesc *
pxesocktodesc(sock)286 pxesocktodesc(sock)
287 	int sock;
288 {
289 
290 #ifdef NETIF_DEBUG
291 	if (sock != 0)
292 		return 0;
293 	else
294 #endif
295 		return &desc;
296 }
297 
298 /*****************************************************************************
299  * PXE initialization and support routines
300  *****************************************************************************/
301 
302 /* static struct btinfo_netif bi_netif; */
303 
304 void
pxeprobe(void)305 pxeprobe(void)
306 {
307 	if (have_pxe < 0) {
308 		pxe_init(1);
309 	}
310 }
311 
312 #define try_pxenv(cp) do {					\
313 	pxenv = (pxenv_t *)cp;					\
314 	if (pxenv->Signature[0] == 'P' &&			\
315 	    pxenv->Signature[1] == 'X' &&			\
316 	    pxenv->Signature[2] == 'E' &&			\
317 	    pxenv->Signature[3] == 'N' &&			\
318 	    pxenv->Signature[4] == 'V' &&			\
319 	    pxenv->Signature[5] == '+') {			\
320 		for (i = 0, ucp = (u_int8_t *)cp, cksum = 0;	\
321 		     i < pxenv->Length; i++)			\
322 			cksum += ucp[i];			\
323 		if (cksum != 0) {				\
324 			printf("\npxe_init: bad cksum (0x%x) "	\
325 			    "for PXENVplus at 0x%lx\n", cksum,	\
326 			    (u_long) cp);			\
327 			pxenv = NULL;				\
328 		}						\
329 	} else							\
330 		pxenv = NULL;					\
331 } while (/* CONSTCOND */ 0)
332 
333 #define try_pxe(cp) do {					\
334 	pxe = (pxe_t *)cp;					\
335 	if (pxe->Signature[0] == '!' &&				\
336 	    pxe->Signature[1] == 'P' &&				\
337 	    pxe->Signature[2] == 'X' &&				\
338 	    pxe->Signature[3] == 'E') {				\
339 		for (i = 0, ucp = (u_int8_t *)cp, cksum = 0;	\
340 		     i < pxe->StructLength; i++)		\
341 			cksum += ucp[i];			\
342 		if (cksum != 0) {				\
343 			printf("pxe_init: bad cksum (0x%x) "	\
344 			    "for bangPXE at 0x%lx\n", cksum,	\
345 			    (u_long) cp);			\
346 			pxe = NULL;				\
347 		}						\
348 	} else							\
349 		pxe = NULL;					\
350 } while (/* CONSTCOND */ 0)
351 
352 int
pxe_init(int quiet)353 pxe_init(int quiet)
354 {
355 	t_PXENV_GET_CACHED_INFO *gci = (void *) pxe_command_buf;
356 	pxenv_t *pxenv;
357 	pxe_t *pxe;
358 	char *cp;
359 	int i;
360 	u_int8_t cksum, *ucp;
361 
362 	if (have_pxe >= 0) {
363 #if PXE_LOUD
364 		printf(" {no:have_pxe=%d}", have_pxe);
365 #endif
366 		return (have_pxe == 0 ? 1 : 0);
367 	}
368 	have_pxe = 0;
369 	if (!(i386_biosflags & 4)) {
370 #if PXE_LOUD
371 		printf(" {pxe_unlikely}");
372 #endif
373 		return (1);	/* not “probably” booted from PXE */
374 	}
375 
376 	/*
377 	 * Checking for the presence of PXE is a machine-dependent
378 	 * operation.  On the IA-32, this can be done two ways:
379 	 *
380 	 *	Int 0x1a function 0x5650
381 	 *
382 	 *	Scan memory for the !PXE or PXENV+ signatures
383 	 *
384 	 * We do the latter, since the Int method returns a pointer
385 	 * to a deprecated structure (PXENV+).
386 	 */
387 
388 	pxenv = NULL;
389 	pxe = NULL;
390 
391 	if (pxe_plus) {
392 #if PXE_LOUD
393 		printf(" {try:plus=%X:%X}", pxe_plus >> 16,
394 		    pxe_plus & 0xFFFF);
395 #endif
396 		try_pxenv(PTOV(pxe_plus >> 16, pxe_plus & 0xFFFF));
397 	}
398 
399 	if (pxe_bang) {
400 #if PXE_LOUD
401 		printf(" {try:bang=%X:%X}", pxe_bang >> 16,
402 		    pxe_bang & 0xFFFF);
403 #endif
404 		try_pxe(PTOV(pxe_bang >> 16, pxe_bang & 0xFFFF));
405 	}
406 
407 	if (pxe_plus == pxe_bang && (pxe || pxenv)) {
408 #if PXE_LOUD
409 		printf(" {pxelinux}");
410 #endif
411 		goto got_one;	/* probably from SYSLINUX */
412 	}
413 
414 	if (!(i386_dosdev & 1)) {
415 #if PXE_LOUD
416 		printf(" {pxe_disabled}");
417 #endif
418 		return (1);	/* PXE scan disabled */
419 	}
420 
421 	for (cp = (char *)0x90000; cp >= (char *)0x10000; cp -= 0x10) {
422 		if (pxenv == NULL)
423 			try_pxenv(cp);
424 		if (pxe == NULL)
425 			try_pxe(cp);
426 
427 		if (pxe != NULL && pxenv != NULL)
428 			break;
429 	}
430 
431 	if (pxe == NULL && pxenv == NULL) {
432 #if !PXE_LOUD
433 		if (!quiet)
434 #endif
435 			printf("pxe_init: No PXE BIOS found.\n");
436 		return 1;
437 	}
438 #if PXE_LOUD
439 	printf(" {scan:pxenv=%X,pxe=%X}", (unsigned)pxenv, (unsigned)pxe);
440 #endif
441 
442  got_one:
443 	if (pxenv && (pxenv != PTOV(pxe_plus >> 16, pxe_plus & 0xFFFF)))
444 		pxe_plus = (((uint32_t)pxenv & 0xFFFF0) << 12) |
445 		    ((uint32_t)pxenv & 0x0000F);
446 	if (pxe && (pxe != PTOV(pxe_bang >> 16, pxe_bang & 0xFFFF)))
447 		pxe_bang = (((uint32_t)pxe & 0xFFFF0) << 12) |
448 		    ((uint32_t)pxe & 0x0000F);
449 
450 	if (pxenv == NULL) {
451 		/* assert(pxe != NULL); */
452 
453 		printf(quiet ? " pxe!" : "PXE present\n");
454 	} else {				/* pxenv != NULL */
455 		int bang = 0;
456 
457 		if (pxenv->Version >= 0x0201 && pxe != NULL) {
458 			/* 2.1 or greater -- don't use PXENV+ */
459 			bang = 1;
460 		}
461 
462 		if (quiet) {
463 			printf(" pxe%c[%d.%d]",
464 			    (bang ? '!' : '+'),
465 			    (pxenv->Version >> 8) & 0xff,
466 			     pxenv->Version & 0xff);
467 		} else {
468 			printf("PXE BIOS Version %d.%d\n",
469 			    (pxenv->Version >> 8) & 0xff,
470 			     pxenv->Version & 0xff);
471 		}
472 
473 		if (bang) {
474 			pxenv = NULL;
475 		}
476 	}
477 
478 	if (pxenv == NULL) {
479 		pxe_call = pxecall_bang;
480 		pxecall_addr = ((uint32_t)pxe->EntryPointSP.segment << 16) |
481 		    pxe->EntryPointSP.offset;
482 	} else {
483 		pxe_call = pxecall_plus;
484 		pxecall_addr = ((uint32_t)pxenv->RMEntry.segment << 16) |
485 		    pxenv->RMEntry.offset;
486 	}
487 
488 	/*
489 	 * Get the cached info from the server's Discovery reply packet.
490 	 */
491 	bzero(gci, sizeof(*gci));
492 	gci->PacketType = PXENV_PACKET_TYPE_CACHED_REPLY;
493 	pxe_call(PXENV_GET_CACHED_INFO);
494 
495 	if (gci->Status != PXENV_STATUS_SUCCESS) {
496 		printf("\npxeinfo: PXENV_GET_CACHED_INFO failed: 0x%x\n",
497 		    gci->Status);
498 		return 1;
499 	}
500 
501 	memcpy(&bootplayer, PTOV(gci->Buffer.segment, gci->Buffer.offset),
502 	    gci->BufferSize);
503 
504 	bcopy(&bootplayer.yip, &myip.s_addr, sizeof(myip.s_addr));
505 	bcopy(&bootplayer.sip, &servip.s_addr, sizeof(servip.s_addr));
506 
507         /* Compute our "natural" netmask. */
508 	if (IN_CLASSA(myip.s_addr))
509 		netmask = IN_CLASSA_NET;
510 	else if (IN_CLASSB(myip.s_addr))
511 		netmask = IN_CLASSB_NET;
512 	else
513 		netmask = IN_CLASSC_NET;
514 
515 	have_pxe = 1;
516 	return 0;
517 }
518 
519 void
pxeinfo(void)520 pxeinfo(void)
521 {
522 	u_int8_t *p;
523 #ifdef PXE_DEBUG
524 	t_PXENV_UNDI_GET_NIC_TYPE *gnt = (void *) pxe_command_buf;
525 #endif
526 
527 	if (have_pxe <= 0) {
528 		printf(" %s\n", have_pxe ? "err" : "none");
529 		return;
530 	}
531 
532 	printf(" %s %X mac %s", pxe_call == pxecall_bang ? "!PXE" : "PXENV+",
533 	    (unsigned)pxecall_addr, ether_sprintf(bootplayer.CAddr));
534 	p = (u_int8_t *)&myip.s_addr;
535 	printf(", ip %d.%d.%d.%d", p[0], p[1], p[2], p[3]);
536 	p = (u_int8_t *)&servip.s_addr;
537 	printf(", server %d.%d.%d.%d", p[0], p[1], p[2], p[3]);
538 
539 #ifdef PXE_DEBUG
540 	/*
541 	 * Get network interface information.
542 	 */
543 	bzero(gnt, sizeof(*gnt));
544 	pxe_call(PXENV_UNDI_GET_NIC_TYPE);
545 
546 	if (gnt->Status != PXENV_STATUS_SUCCESS) {
547 		printf("\npxeinfo: PXENV_UNDI_GET_NIC_TYPE failed: 0x%x\n",
548 		    gnt->Status);
549 		return;
550 	}
551 
552 	switch (gnt->NicType) {
553 	case PCI_NIC:
554 	case CardBus_NIC:
555 		/* strncpy(bi_netif.ifname, "pxe", sizeof(bi_netif.ifname)); */
556 		/* bi_netif.bus = BI_BUS_PCI; */
557 		/* bi_netif.addr.tag = gnt->info.pci.BusDevFunc; */
558 
559 		printf("\nPXE: Using %s device at bus %d device %d function %d\n",
560 		    gnt->NicType == PCI_NIC ? "PCI" : "CardBus",
561 		    (gnt->info.pci.BusDevFunc >> 8) & 0xff,
562 		    (gnt->info.pci.BusDevFunc >> 3) & 0x1f,
563 		    gnt->info.pci.BusDevFunc & 0x7);
564 		break;
565 
566 	case PnP_NIC:
567 		/* XXX Make bootinfo work with this. */
568 		printf("\nPXE: Using PnP device at 0x%x\n",
569 		    gnt->info.pnp.CardSelNum);
570 	}
571 #endif
572 }
573 
574 void
pxe_shutdown(void)575 pxe_shutdown(void)
576 {
577 	int try;
578 	t_PXENV_UNLOAD_STACK *unload = (void *) pxe_command_buf;
579 	t_PXENV_UNDI_SHUTDOWN *shutdown = (void *) pxe_command_buf;
580 #ifdef PXE_DEBUG
581 	t_PXENV_UDP_CLOSE *close = (void *) pxe_command_buf;
582 #endif
583 
584 	if (pxe_call == NULL)
585 		return;
586 
587 	/* Close any open UDP connections.  Ignore return value. */
588 	pxe_call(PXENV_UDP_CLOSE);
589 #ifdef PXE_DEBUG
590 	printf("pxe_shutdown: PXENV_UDP_CLOSE returned 0x%x\n", close->status);
591 #endif
592 
593 	/* Sometimes PXENV_UNDI_SHUTDOWN doesn't work at first */
594 	for (try = 3; try > 0; try--) {
595 		pxe_call(PXENV_UNDI_SHUTDOWN);
596 
597 		if (shutdown->Status == PXENV_STATUS_SUCCESS)
598 			break;
599 
600 		printf("pxe_shutdown: PXENV_UNDI_SHUTDOWN failed: 0x%x\n",
601 		    shutdown->Status);
602 
603 		if (try != 1)
604 			sleep(1);
605 	}
606 
607 	/* Have multiple attempts at PXENV_UNLOAD_STACK, too */
608 	for (try = 3; try > 0; try--) {
609 		pxe_call(PXENV_UNLOAD_STACK);
610 
611 		if (unload->Status == PXENV_STATUS_SUCCESS)
612 			break;
613 
614 		printf("pxe_shutdown: PXENV_UNLOAD_STACK failed: 0x%x\n",
615 		    unload->Status);
616 
617 		if (try != 1)
618 			sleep(1);
619 	}
620 }
621 
622 extern void pxecheck(void);
623 
624 int
Xpxe(void)625 Xpxe(void)
626 {
627 	have_pxe = -1;
628 #if 0
629 	pxe_plus = pxe_bang = 0;	/* override potentially passed stuff */
630 #endif
631 	i386_biosflags |= 4;		/* no pxe_unlikely */
632 	i386_dosdev |= 1;		/* no pxe_disabled */
633 
634 	if (pxe_init(0))
635 		printf("Sorry, scan for PXE yielded no result.\n");
636 	else {
637 		printf("Yes, we have found a PXE boot ROM.\n=>");
638 		i386_biosflags &= ~4;	/* tftp is not the boot device */
639 		pxecheck();
640 		pxeinfo();
641 		putchar('\n');
642 	}
643 	return (0);
644 }
645