xref: /freebsd/stand/i386/libi386/pxe.c (revision 495826f69d96857bf0559516502e058ecab4ee4d)
1 /*-
2  * Copyright (c) 2000 Alfred Perlstein <alfred@freebsd.org>
3  * Copyright (c) 2000 Paul Saab <ps@freebsd.org>
4  * All rights reserved.
5  * Copyright (c) 2000 John Baldwin <jhb@freebsd.org>
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  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include <stand.h>
30 #include <errno.h>
31 #include <stdbool.h>
32 #include <stddef.h>
33 #include <string.h>
34 #include <stdarg.h>
35 #include <sys/param.h>
36 
37 #include <net/ethernet.h>
38 #include <netinet/in_systm.h>
39 #include <netinet/in.h>
40 #include <netinet/ip.h>
41 #include <netinet/udp.h>
42 
43 #include <net.h>
44 #include <netif.h>
45 #include <nfsv2.h>
46 #include <iodesc.h>
47 
48 #include <bootp.h>
49 #include <bootstrap.h>
50 #include "libi386.h"
51 #include "btxv86.h"
52 #include "pxe.h"
53 
54 static pxenv_t *pxenv_p = NULL;	/* PXENV+ */
55 static pxe_t *pxe_p = NULL;		/* !PXE */
56 
57 #ifdef PXE_DEBUG
58 static int	pxe_debug = 0;
59 #endif
60 
61 void		pxe_enable(void *pxeinfo);
62 static void	(*pxe_call)(int func, void *ptr);
63 static void	pxenv_call(int func, void *ptr);
64 static void	bangpxe_call(int func, void *ptr);
65 
66 static int	pxe_init(void);
67 static int	pxe_print(int verbose);
68 static void	pxe_cleanup(void);
69 
70 static void	pxe_perror(int error);
71 static int	pxe_netif_match(struct netif *nif, void *machdep_hint);
72 static int	pxe_netif_probe(struct netif *nif, void *machdep_hint);
73 static void	pxe_netif_init(struct iodesc *desc, void *machdep_hint);
74 static ssize_t	pxe_netif_get(struct iodesc *, void **, time_t);
75 static ssize_t	pxe_netif_put(struct iodesc *desc, void *pkt, size_t len);
76 static void	pxe_netif_end(struct netif *nif);
77 
78 extern struct netif_stats	pxe_st[];
79 extern uint16_t			__bangpxeseg;
80 extern uint16_t			__bangpxeoff;
81 extern void			__bangpxeentry(void);
82 extern uint16_t			__pxenvseg;
83 extern uint16_t			__pxenvoff;
84 extern void			__pxenventry(void);
85 
86 struct netif_dif pxe_ifs[] = {
87 /*	dif_unit        dif_nsel        dif_stats       dif_private     */
88 	{0,             1,              &pxe_st[0],     0}
89 };
90 
91 struct netif_stats pxe_st[nitems(pxe_ifs)];
92 
93 struct netif_driver pxenetif = {
94 	.netif_bname = "pxenet",
95 	.netif_match = pxe_netif_match,
96 	.netif_probe = pxe_netif_probe,
97 	.netif_init = pxe_netif_init,
98 	.netif_get = pxe_netif_get,
99 	.netif_put = pxe_netif_put,
100 	.netif_end = pxe_netif_end,
101 	.netif_ifs = pxe_ifs,
102 	.netif_nifs = nitems(pxe_ifs)
103 };
104 
105 struct netif_driver *netif_drivers[] = {
106 	&pxenetif,
107 	NULL
108 };
109 
110 struct devsw pxedisk = {
111 	.dv_name = "net",
112 	.dv_type = DEVT_NET,
113 	.dv_init = pxe_init,
114 	.dv_strategy = NULL,	/* Will be set in pxe_init */
115 	.dv_open = NULL,	/* Will be set in pxe_init */
116 	.dv_close = NULL,	/* Will be set in pxe_init */
117 	.dv_ioctl = noioctl,
118 	.dv_print = pxe_print,
119 	.dv_cleanup = pxe_cleanup,
120 };
121 
122 /*
123  * This function is called by the loader to enable PXE support if we
124  * are booted by PXE. The passed in pointer is a pointer to the PXENV+
125  * structure.
126  */
127 void
pxe_enable(void * pxeinfo)128 pxe_enable(void *pxeinfo)
129 {
130 	pxenv_p  = (pxenv_t *)pxeinfo;
131 	pxe_p    = (pxe_t *)PTOV(pxenv_p->PXEPtr.segment * 16 +
132 				 pxenv_p->PXEPtr.offset);
133 	pxe_call = NULL;
134 }
135 
136 /*
137  * return true if pxe structures are found/initialized,
138  * also figures out our IP information via the pxe cached info struct
139  */
140 static int
pxe_init(void)141 pxe_init(void)
142 {
143 	t_PXENV_GET_CACHED_INFO *gci_p;
144 	int counter;
145 	uint8_t checksum;
146 	uint8_t *checkptr;
147 	extern struct devsw netdev;
148 
149 	if (pxenv_p == NULL)
150 		return (0);
151 
152 	/* RFC 4578 § 2.1: BIOS PXE is a 32-bit "Standard PC BIOS" client. */
153 	bootp_client_arch = 0x0000;
154 
155 	/* look for "PXENV+" */
156 	if (bcmp((void *)pxenv_p->Signature, S_SIZE("PXENV+"))) {
157 		pxenv_p = NULL;
158 		return (0);
159 	}
160 
161 	/* make sure the size is something we can handle */
162 	if (pxenv_p->Length > sizeof(*pxenv_p)) {
163 		printf("PXENV+ structure too large, ignoring\n");
164 		pxenv_p = NULL;
165 		return (0);
166 	}
167 
168 	/*
169 	 * do byte checksum:
170 	 * add up each byte in the structure, the total should be 0
171 	 */
172 	checksum = 0;
173 	checkptr = (uint8_t *) pxenv_p;
174 	for (counter = 0; counter < pxenv_p->Length; counter++)
175 		checksum += *checkptr++;
176 	if (checksum != 0) {
177 		printf("PXENV+ structure failed checksum, ignoring\n");
178 		pxenv_p = NULL;
179 		return (0);
180 	}
181 
182 	/*
183 	 * PXENV+ passed, so use that if !PXE is not available or
184 	 * the checksum fails.
185 	 */
186 	pxe_call = pxenv_call;
187 	if (pxenv_p->Version >= 0x0200) {
188 		for (;;) {
189 			if (bcmp((void *)pxe_p->Signature, S_SIZE("!PXE"))) {
190 				pxe_p = NULL;
191 				break;
192 			}
193 			checksum = 0;
194 			checkptr = (uint8_t *)pxe_p;
195 			for (counter = 0; counter < pxe_p->StructLength;
196 			    counter++)
197 				checksum += *checkptr++;
198 			if (checksum != 0) {
199 				pxe_p = NULL;
200 				break;
201 			}
202 			pxe_call = bangpxe_call;
203 			break;
204 		}
205 	}
206 
207 	pxedisk.dv_open = netdev.dv_open;
208 	pxedisk.dv_close = netdev.dv_close;
209 	pxedisk.dv_strategy = netdev.dv_strategy;
210 
211 	printf("\nPXE version %d.%d, real mode entry point ",
212 	    (uint8_t) (pxenv_p->Version >> 8),
213 	    (uint8_t) (pxenv_p->Version & 0xFF));
214 	if (pxe_call == bangpxe_call)
215 		printf("@%04x:%04x\n",
216 		    pxe_p->EntryPointSP.segment,
217 		    pxe_p->EntryPointSP.offset);
218 	else
219 		printf("@%04x:%04x\n",
220 		    pxenv_p->RMEntry.segment, pxenv_p->RMEntry.offset);
221 
222 	gci_p = bio_alloc(sizeof(*gci_p));
223 	if (gci_p == NULL) {
224 		pxe_p = NULL;
225 		return (0);
226 	}
227 	bzero(gci_p, sizeof(*gci_p));
228 	gci_p->PacketType = PXENV_PACKET_TYPE_BINL_REPLY;
229 	pxe_call(PXENV_GET_CACHED_INFO, gci_p);
230 	if (gci_p->Status != 0) {
231 		pxe_perror(gci_p->Status);
232 		bio_free(gci_p, sizeof(*gci_p));
233 		pxe_p = NULL;
234 		return (0);
235 	}
236 	free(bootp_response);
237 	if ((bootp_response = malloc(gci_p->BufferSize)) != NULL) {
238 		bootp_response_size = gci_p->BufferSize;
239 		bcopy(PTOV((gci_p->Buffer.segment << 4) + gci_p->Buffer.offset),
240 		    bootp_response, bootp_response_size);
241 	}
242 	bio_free(gci_p, sizeof(*gci_p));
243 	return (1);
244 }
245 
246 static int
pxe_print(int verbose)247 pxe_print(int verbose)
248 {
249 	if (pxe_call == NULL)
250 		return (0);
251 
252 	printf("%s devices:", pxedisk.dv_name);
253 	if (pager_output("\n") != 0)
254 		return (1);
255 	printf("    %s0:", pxedisk.dv_name);
256 	if (verbose) {
257 		printf("    %s:%s", inet_ntoa(rootip), rootpath);
258 	}
259 	return (pager_output("\n"));
260 }
261 
262 static void
pxe_cleanup(void)263 pxe_cleanup(void)
264 {
265 	t_PXENV_UNLOAD_STACK *unload_stack_p;
266 	t_PXENV_UNDI_SHUTDOWN *undi_shutdown_p;
267 
268 	if (pxe_call == NULL)
269 		return;
270 
271 	undi_shutdown_p = bio_alloc(sizeof(*undi_shutdown_p));
272 	if (undi_shutdown_p != NULL) {
273 		bzero(undi_shutdown_p, sizeof(*undi_shutdown_p));
274 		pxe_call(PXENV_UNDI_SHUTDOWN, undi_shutdown_p);
275 
276 #ifdef PXE_DEBUG
277 		if (pxe_debug && undi_shutdown_p->Status != 0)
278 			printf("pxe_cleanup: UNDI_SHUTDOWN failed %x\n",
279 			    undi_shutdown_p->Status);
280 #endif
281 		bio_free(undi_shutdown_p, sizeof(*undi_shutdown_p));
282 	}
283 
284 	unload_stack_p = bio_alloc(sizeof(*unload_stack_p));
285 	if (unload_stack_p != NULL) {
286 		bzero(unload_stack_p, sizeof(*unload_stack_p));
287 		pxe_call(PXENV_UNLOAD_STACK, unload_stack_p);
288 
289 #ifdef PXE_DEBUG
290 		if (pxe_debug && unload_stack_p->Status != 0)
291 			printf("pxe_cleanup: UNLOAD_STACK failed %x\n",
292 			    unload_stack_p->Status);
293 #endif
294 		bio_free(unload_stack_p, sizeof(*unload_stack_p));
295 	}
296 }
297 
298 void
pxe_perror(int err)299 pxe_perror(int err)
300 {
301 	return;
302 }
303 
304 void
pxenv_call(int func,void * ptr)305 pxenv_call(int func, void *ptr)
306 {
307 #ifdef PXE_DEBUG
308 	if (pxe_debug)
309 		printf("pxenv_call %x\n", func);
310 #endif
311 
312 	bzero(&v86, sizeof(v86));
313 
314 	__pxenvseg = pxenv_p->RMEntry.segment;
315 	__pxenvoff = pxenv_p->RMEntry.offset;
316 
317 	v86.ctl  = V86_ADDR | V86_CALLF | V86_FLAGS;
318 	v86.es   = VTOPSEG(ptr);
319 	v86.edi  = VTOPOFF(ptr);
320 	v86.addr = (VTOPSEG(__pxenventry) << 16) | VTOPOFF(__pxenventry);
321 	v86.ebx  = func;
322 	v86int();
323 	v86.ctl  = V86_FLAGS;
324 }
325 
326 void
bangpxe_call(int func,void * ptr)327 bangpxe_call(int func, void *ptr)
328 {
329 #ifdef PXE_DEBUG
330 	if (pxe_debug)
331 		printf("bangpxe_call %x\n", func);
332 #endif
333 
334 	bzero(&v86, sizeof(v86));
335 
336 	__bangpxeseg = pxe_p->EntryPointSP.segment;
337 	__bangpxeoff = pxe_p->EntryPointSP.offset;
338 
339 	v86.ctl  = V86_ADDR | V86_CALLF | V86_FLAGS;
340 	v86.edx  = VTOPSEG(ptr);
341 	v86.eax  = VTOPOFF(ptr);
342 	v86.addr = (VTOPSEG(__bangpxeentry) << 16) | VTOPOFF(__bangpxeentry);
343 	v86.ebx  = func;
344 	v86int();
345 	v86.ctl  = V86_FLAGS;
346 }
347 
348 
349 static int
pxe_netif_match(struct netif * nif,void * machdep_hint)350 pxe_netif_match(struct netif *nif, void *machdep_hint)
351 {
352 	return (1);
353 }
354 
355 static int
pxe_netif_probe(struct netif * nif,void * machdep_hint)356 pxe_netif_probe(struct netif *nif, void *machdep_hint)
357 {
358 	if (pxe_call == NULL)
359 		return (-1);
360 
361 	return (0);
362 }
363 
364 static void
pxe_netif_end(struct netif * nif)365 pxe_netif_end(struct netif *nif)
366 {
367 	t_PXENV_UNDI_CLOSE *undi_close_p;
368 
369 	undi_close_p = bio_alloc(sizeof(*undi_close_p));
370 	if (undi_close_p != NULL) {
371 		bzero(undi_close_p, sizeof(*undi_close_p));
372 		pxe_call(PXENV_UNDI_CLOSE, undi_close_p);
373 		if (undi_close_p->Status != 0)
374 			printf("undi close failed: %x\n", undi_close_p->Status);
375 		bio_free(undi_close_p, sizeof(*undi_close_p));
376 	}
377 }
378 
379 static void
pxe_netif_init(struct iodesc * desc,void * machdep_hint)380 pxe_netif_init(struct iodesc *desc, void *machdep_hint)
381 {
382 	t_PXENV_UNDI_GET_INFORMATION *undi_info_p;
383 	t_PXENV_UNDI_OPEN *undi_open_p;
384 	uint8_t *mac;
385 	int i, len;
386 
387 	undi_info_p = bio_alloc(sizeof(*undi_info_p));
388 	if (undi_info_p == NULL)
389 		return;
390 
391 	bzero(undi_info_p, sizeof(*undi_info_p));
392 	pxe_call(PXENV_UNDI_GET_INFORMATION, undi_info_p);
393 	if (undi_info_p->Status != 0) {
394 		printf("undi get info failed: %x\n", undi_info_p->Status);
395 		bio_free(undi_info_p, sizeof(*undi_info_p));
396 		return;
397 	}
398 
399 	/* Make sure the CurrentNodeAddress is valid. */
400 	for (i = 0; i < undi_info_p->HwAddrLen; ++i) {
401 		if (undi_info_p->CurrentNodeAddress[i] != 0)
402 			break;
403 	}
404 	if (i < undi_info_p->HwAddrLen) {
405 		for (i = 0; i < undi_info_p->HwAddrLen; ++i) {
406 			if (undi_info_p->CurrentNodeAddress[i] != 0xff)
407 				break;
408 		}
409 	}
410 	if (i < undi_info_p->HwAddrLen)
411 		mac = undi_info_p->CurrentNodeAddress;
412 	else
413 		mac = undi_info_p->PermNodeAddress;
414 
415 	len = min(sizeof (desc->myea), undi_info_p->HwAddrLen);
416 	for (i = 0; i < len; ++i)
417 		desc->myea[i] = mac[i];
418 
419 	bio_free(undi_info_p, sizeof(*undi_info_p));
420 	undi_open_p = bio_alloc(sizeof(*undi_open_p));
421 	if (undi_open_p == NULL)
422 		return;
423 	bzero(undi_open_p, sizeof(*undi_open_p));
424 	undi_open_p->PktFilter = FLTR_DIRECTED | FLTR_BRDCST;
425 	pxe_call(PXENV_UNDI_OPEN, undi_open_p);
426 	if (undi_open_p->Status != 0)
427 		printf("undi open failed: %x\n", undi_open_p->Status);
428 	bio_free(undi_open_p, sizeof(*undi_open_p));
429 }
430 
431 static int
pxe_netif_receive_isr(t_PXENV_UNDI_ISR * isr,void ** pkt,ssize_t * retsize)432 pxe_netif_receive_isr(t_PXENV_UNDI_ISR *isr, void **pkt, ssize_t *retsize)
433 {
434 	static bool data_pending;
435 	char *buf, *ptr, *frame;
436 	size_t size, rsize;
437 
438 	buf = NULL;
439 	size = rsize = 0;
440 
441 	/*
442 	 * We can save ourselves the next two pxe calls because we already know
443 	 * we weren't done grabbing everything.
444 	 */
445 	if (data_pending) {
446 		data_pending = false;
447 		goto nextbuf;
448 	}
449 
450 	/*
451 	 * We explicitly don't check for OURS/NOT_OURS as a result of START;
452 	 * it's been reported that some cards are known to mishandle these.
453 	 */
454 	bzero(isr, sizeof(*isr));
455 	isr->FuncFlag = PXENV_UNDI_ISR_IN_START;
456 	pxe_call(PXENV_UNDI_ISR, isr);
457 	/* We could translate Status... */
458 	if (isr->Status != 0) {
459 		return (ENXIO);
460 	}
461 
462 	bzero(isr, sizeof(*isr));
463 	isr->FuncFlag = PXENV_UNDI_ISR_IN_PROCESS;
464 	pxe_call(PXENV_UNDI_ISR, isr);
465 	if (isr->Status != 0) {
466 		return (ENXIO);
467 	}
468 	if (isr->FuncFlag == PXENV_UNDI_ISR_OUT_BUSY) {
469 		/*
470 		 * Let the caller decide if we need to be restarted.  It will
471 		 * currently blindly restart us, but it could check timeout in
472 		 * the future.
473 		 */
474 		return (ERESTART);
475 	}
476 
477 	/*
478 	 * By design, we'll hardly ever hit this terminal condition unless we
479 	 * pick up nothing but tx interrupts here.  More frequently, we will
480 	 * process rx buffers until we hit the terminal condition in the middle.
481 	 */
482 	while (isr->FuncFlag != PXENV_UNDI_ISR_OUT_DONE) {
483 		/*
484 		 * This might have given us PXENV_UNDI_ISR_OUT_TRANSMIT, in
485 		 * which case we can just disregard and move on to the next
486 		 * buffer/frame.
487 		 */
488 		if (isr->FuncFlag != PXENV_UNDI_ISR_OUT_RECEIVE)
489 			goto nextbuf;
490 
491 		if (buf == NULL) {
492 			/*
493 			 * Grab size from the first Frame that we picked up,
494 			 * allocate an rx buf to hold.  Careful here, as we may
495 			 * see a fragmented frame that's spread out across
496 			 * multiple GET_NEXT calls.
497 			 */
498 			size = isr->FrameLength;
499 			buf = malloc(size + ETHER_ALIGN);
500 			if (buf == NULL)
501 				return (ENOMEM);
502 
503 			ptr = buf + ETHER_ALIGN;
504 		}
505 
506 		frame = (char *)((uintptr_t)isr->Frame.segment << 4);
507 		frame += isr->Frame.offset;
508 		bcopy(PTOV(frame), ptr, isr->BufferLength);
509 		ptr += isr->BufferLength;
510 		rsize += isr->BufferLength;
511 
512 		/*
513 		 * Stop here before we risk catching the start of another frame.
514 		 * It would be nice to continue reading until we actually get a
515 		 * PXENV_UNDI_ISR_OUT_DONE, but our network stack in libsa isn't
516 		 * suitable for reading more than one packet at a time.
517 		 */
518 		if (rsize >= size) {
519 			data_pending = true;
520 			break;
521 		}
522 
523 nextbuf:
524 		bzero(isr, sizeof(*isr));
525 		isr->FuncFlag = PXENV_UNDI_ISR_IN_GET_NEXT;
526 		pxe_call(PXENV_UNDI_ISR, isr);
527 		if (isr->Status != 0) {
528 			free(buf);
529 			return (ENXIO);
530 		}
531 	}
532 
533 	/*
534 	 * We may have never picked up a frame at all (all tx), in which case
535 	 * the caller should restart us.
536 	 */
537 	if (rsize == 0) {
538 		return (ERESTART);
539 	}
540 
541 	*pkt = buf;
542 	*retsize = rsize;
543 	return (0);
544 }
545 
546 static int
pxe_netif_receive(void ** pkt,ssize_t * size)547 pxe_netif_receive(void **pkt, ssize_t *size)
548 {
549 	t_PXENV_UNDI_ISR *isr;
550 	int ret;
551 
552 	isr = bio_alloc(sizeof(*isr));
553 	if (isr == NULL)
554 		return (ENOMEM);
555 
556 	/*
557 	 * This completely ignores the timeout specified in pxe_netif_get(), but
558 	 * we shouldn't be running long enough here for that to make a
559 	 * difference.
560 	 */
561 	for (;;) {
562 		/* We'll only really re-enter for PXENV_UNDI_ISR_OUT_BUSY. */
563 		ret = pxe_netif_receive_isr(isr, pkt, size);
564 		if (ret != ERESTART)
565 			break;
566 	}
567 
568 	bio_free(isr, sizeof(*isr));
569 	return (ret);
570 }
571 
572 static ssize_t
pxe_netif_get(struct iodesc * desc,void ** pkt,time_t timeout)573 pxe_netif_get(struct iodesc *desc, void **pkt, time_t timeout)
574 {
575 	time_t t;
576 	void *ptr;
577 	int ret = -1;
578 	ssize_t size;
579 
580 	t = getsecs();
581 	size = 0;
582 	while ((getsecs() - t) < timeout) {
583 		ret = pxe_netif_receive(&ptr, &size);
584 		if (ret != -1) {
585 			*pkt = ptr;
586 			break;
587 		}
588 	}
589 
590 	return (ret == 0 ? size : -1);
591 }
592 
593 static ssize_t
pxe_netif_put(struct iodesc * desc,void * pkt,size_t len)594 pxe_netif_put(struct iodesc *desc, void *pkt, size_t len)
595 {
596 	t_PXENV_UNDI_TRANSMIT *trans_p;
597 	t_PXENV_UNDI_TBD *tbd_p;
598 	char *data;
599 	ssize_t rv = -1;
600 
601 	trans_p = bio_alloc(sizeof(*trans_p));
602 	tbd_p = bio_alloc(sizeof(*tbd_p));
603 	data = bio_alloc(len);
604 
605 	if (trans_p != NULL && tbd_p != NULL && data != NULL) {
606 		bzero(trans_p, sizeof(*trans_p));
607 		bzero(tbd_p, sizeof(*tbd_p));
608 
609 		trans_p->TBD.segment = VTOPSEG(tbd_p);
610 		trans_p->TBD.offset  = VTOPOFF(tbd_p);
611 
612 		tbd_p->ImmedLength = len;
613 		tbd_p->Xmit.segment = VTOPSEG(data);
614 		tbd_p->Xmit.offset  = VTOPOFF(data);
615 		bcopy(pkt, data, len);
616 
617 		pxe_call(PXENV_UNDI_TRANSMIT, trans_p);
618 		if (trans_p->Status == 0)
619 			rv = len;
620 	}
621 
622 	bio_free(data, len);
623 	bio_free(tbd_p, sizeof(*tbd_p));
624 	bio_free(trans_p, sizeof(*trans_p));
625 	return (rv);
626 }
627