xref: /netbsd-src/usr.sbin/ndbootd/ndbootd.c (revision 23c8222edbfb0f0932d88a8351d3a0cf817dfb9e)
1 /*	$NetBSD: ndbootd.c,v 1.8 2003/08/17 22:34:17 itojun Exp $	*/
2 
3 /* ndbootd.c - the Sun Network Disk (nd) daemon: */
4 
5 /*
6  * Copyright (c) 2001 Matthew Fredette.  All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  *   1. Redistributions of source code must retain the above copyright
12  *      notice, this list of conditions and the following disclaimer.
13  *   2. Redistributions in binary form must reproduce the above copyright
14  *      notice, this list of conditions and the following disclaimer in the
15  *      documentation and/or other materials provided with the distribution.
16  *   3. All advertising materials mentioning features or use of this software
17  *      must display the following acknowledgement:
18  *        This product includes software developed by Matthew Fredette.
19  *   4. The name of Matthew Fredette may not be used to endorse or promote
20  *      products derived from this software without specific prior written
21  *      permission.
22  *
23  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
24  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
25  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
26  */
27 
28 /* <<Header: /data/home/fredette/project/THE-WEIGHT-CVS/ndbootd/ndbootd.c,v 1.9 2001/06/13 21:19:11 fredette Exp >> */
29 
30 /*
31  * <<Log: ndbootd.c,v >>
32  * Revision 1.9  2001/06/13 21:19:11  fredette
33  * (main): Don't assume that a successful, but short, read
34  * leaves a zero in errno.  Instead, just check for the short
35  * read by looking at the byte count that read returned.
36  *
37  * Revision 1.8  2001/05/23 02:35:36  fredette
38  * Changed many debugging printfs to compile quietly on the
39  * alpha.  Patch from Andrew Brown <atatat@atatdot.net>.
40  *
41  * Revision 1.7  2001/05/22 13:13:20  fredette
42  * Ran indent(1) with NetBSD's KNF-approximating profile.
43  *
44  * Revision 1.6  2001/05/22 12:53:40  fredette
45  * [HAVE_STRICT_ALIGNMENT]: Added code to copy packet headers
46  * between the buffer and local variables, to satisfy
47  * alignment constraints.
48  *
49  * Revision 1.5  2001/05/15 14:43:24  fredette
50  * Now have prototypes for the allocation functions.
51  * (main): Now handle boot blocks that aren't an integral
52  * multiple of the block size.
53  *
54  * Revision 1.4  2001/05/09 20:53:38  fredette
55  * (main): Now insert a small delay before sending each packet.
56  * Sending packets too quickly apparently overwhelms clients.
57  * Added new single-letter versions of all options that didn't
58  * already have them.  Expanded some debug messages, and fixed
59  * others to display Ethernet addresses correctly.
60  *
61  * Revision 1.3  2001/01/31 17:35:50  fredette
62  * (main): Fixed various printf argument lists.
63  *
64  * Revision 1.2  2001/01/30 15:35:38  fredette
65  * Now, ndbootd assembles disk images for clients on-the-fly.
66  * Defined many new macros related to this.
67  * (main): Added support for the --boot2 option.  Turned the
68  * original disk-image filename into the filename of the
69  * first-stage boot program.  Now do better multiple-client
70  * support, especially when it comes to checking if a client
71  * is really ours.  Now assemble client-specific disk images
72  * on-the-fly, potentially serving each client a different
73  * second-stage boot.
74  *
75  * Revision 1.1  2001/01/29 15:12:13  fredette
76  * Added.
77  *
78  */
79 
80 #include <sys/cdefs.h>
81 #if 0
82 static const char _ndbootd_c_rcsid[] = "<<Id: ndbootd.c,v 1.9 2001/06/13 21:19:11 fredette Exp >>";
83 #else
84 __RCSID("$NetBSD: ndbootd.c,v 1.8 2003/08/17 22:34:17 itojun Exp $");
85 #endif
86 
87 /* includes: */
88 #include "ndbootd.h"
89 
90 /* the number of blocks that Sun-2 PROMs load, starting from block
91    zero: */
92 #define NDBOOTD_PROM_BLOCK_COUNT (16)
93 
94 /* the first block number of the (dummy) Sun disklabel: */
95 #define NDBOOTD_SUNDK_BLOCK_FIRST (0)
96 
97 /* the number of blocks in the (dummy) Sun disklabel: */
98 #define NDBOOTD_SUNDK_BLOCK_COUNT (1)
99 
100 /* the first block number of the first-stage boot program.
101    the first-stage boot program begins right after the (dummy)
102    Sun disklabel: */
103 #define NDBOOTD_BOOT1_BLOCK_FIRST (NDBOOTD_SUNDK_BLOCK_FIRST + NDBOOTD_SUNDK_BLOCK_COUNT)
104 
105 /* the number of blocks in the first-stage boot program: */
106 #define NDBOOTD_BOOT1_BLOCK_COUNT (NDBOOTD_PROM_BLOCK_COUNT - NDBOOTD_BOOT1_BLOCK_FIRST)
107 
108 /* the first block number of any second-stage boot program.
109    any second-stage boot program begins right after the first-stage boot program: */
110 #define NDBOOTD_BOOT2_BLOCK_FIRST (NDBOOTD_BOOT1_BLOCK_FIRST + NDBOOTD_BOOT1_BLOCK_COUNT)
111 
112 /* this macro returns the number of bytes available in an object starting at a given offset: */
113 #define NDBOOTD_BYTES_AVAIL(block_number, byte_offset, obj_block_first, obj_block_count) \
114   ((((ssize_t) (obj_block_count) - (ssize_t) ((block_number) - (obj_block_first))) * NDBOOT_BSIZE) - (ssize_t) (byte_offset))
115 
116 /* this determines how long we can cache file descriptors and RARP
117    information: */
118 #define NDBOOTD_CLIENT_TTL_SECONDS (10)
119 
120 /* this determines how long we wait before sending a packet: */
121 #define NDBOOTD_SEND_DELAY_NSECONDS (10000000)
122 
123 /* this macro helps us size a struct ifreq: */
124 #ifdef HAVE_SOCKADDR_SA_LEN
125 #define SIZEOF_IFREQ(ifr) (sizeof((ifr)->ifr_name) + (ifr)->ifr_addr.sa_len)
126 #else				/* !HAVE_SOCKADDR_SA_LEN */
127 #define SIZEOF_IFREQ(ifr) (sizeof((ifr)->ifr_name) + sizeof(struct sockaddr))
128 #endif				/* !HAVE_SOCKADDR_SA_LEN */
129 
130 /* prototypes: */
131 void *ndbootd_malloc _NDBOOTD_P((size_t));
132 void *ndbootd_malloc0 _NDBOOTD_P((size_t));
133 void *ndbootd_memdup _NDBOOTD_P((void *, size_t));
134 
135 /* globals: */
136 const char *_ndbootd_argv0;
137 #ifdef _NDBOOTD_DO_DEBUG
138 int _ndbootd_debug;
139 #endif				/* _NDBOOTD_DO_DEBUG */
140 
141 /* allocators: */
142 void *
143 ndbootd_malloc(size_t size)
144 {
145 	void *buffer;
146 	if ((buffer = malloc(size)) == NULL) {
147 		abort();
148 	}
149 	return (buffer);
150 }
151 void *
152 ndbootd_malloc0(size_t size)
153 {
154 	void *buffer;
155 	buffer = ndbootd_malloc(size);
156 	memset(buffer, 0, size);
157 	return (buffer);
158 }
159 void *
160 ndbootd_memdup(void *buffer0, size_t size)
161 {
162 	void *buffer1;
163 	buffer1 = ndbootd_malloc(size);
164 	memcpy(buffer1, buffer0, size);
165 	return (buffer1);
166 }
167 #define ndbootd_free free
168 #define ndbootd_new(t, c) ((t *) ndbootd_malloc(sizeof(t) * (c)))
169 #define ndbootd_new0(t, c) ((t *) ndbootd_malloc0(sizeof(t) * (c)))
170 #define ndbootd_dup(t, b, c) ((t *) ndbootd_memdup(b, c))
171 
172 /* this calculates an IP packet header checksum: */
173 static void
174 _ndbootd_ip_cksum(struct ip * ip_packet)
175 {
176 	u_int16_t *_word, word;
177 	u_int32_t checksum;
178 	unsigned int byte_count, bytes_left;
179 
180 	/* we assume that the IP packet header is 16-bit aligned: */
181 	assert((((unsigned long) ip_packet) % sizeof(word)) == 0);
182 
183 	/* initialize for the checksum: */
184 	checksum = 0;
185 
186 	/* sum up the packet contents: */
187 	_word = (u_int16_t *) ip_packet;
188 	byte_count = ip_packet->ip_hl << 2;
189 	for (bytes_left = byte_count; bytes_left >= sizeof(*_word);) {
190 		checksum += *(_word++);
191 		bytes_left -= sizeof(*_word);
192 	}
193 	word = 0;
194 	memcpy(&word, _word, bytes_left);
195 	checksum += word;
196 
197 	/* finish the checksum: */
198 	checksum = (checksum >> 16) + (checksum & 0xffff);
199 	checksum += (checksum >> 16);
200 	checksum = ~checksum;
201 	ip_packet->ip_sum = checksum;
202 }
203 /* this finds a network interface: */
204 static struct ndbootd_interface *
205 _ndbootd_find_interface(const char *ifr_name_user)
206 {
207 	struct ifreq ifr;
208 #ifdef HAVE_AF_LINK
209 	struct ifaddrs *link_ifas[20];	/* FIXME - magic constant. */
210 	size_t link_ifas_count;
211 	size_t link_ifas_i;
212 	struct sockaddr_dl *sadl;
213 #endif				/* HAVE_AF_LINK */
214 	struct ndbootd_interface *interface;
215 	struct ifaddrs *ifap, *ifa, *ifa_user;
216 
217 	/* read the interface list: */
218 	if (getifaddrs(&ifap) != 0) {
219 		return (NULL);
220 	}
221 #ifdef HAVE_AF_LINK
222 	/* start our list of link address ifas: */
223 	link_ifas_count = 0;
224 #endif				/* HAVE_AF_LINK */
225 
226 	/* walk the interface list: */
227 	ifa_user = NULL;
228 	for (ifa = ifap; ifa; ifa = ifa->ifa_next) {
229 #ifdef HAVE_AF_LINK
230 		/* if this is a hardware address, save it: */
231 		if (ifa->ifa_addr->sa_family == AF_LINK) {
232 			if (link_ifas_count < (sizeof(link_ifas) / sizeof(link_ifas[0]))) {
233 				link_ifas[link_ifas_count++] = ifa;
234 			}
235 			continue;
236 		}
237 #endif				/* HAVE_AF_LINK */
238 
239 		/* ignore this interface if it doesn't do IP: */
240 		if (ifa->ifa_addr->sa_family != AF_INET) {
241 			continue;
242 		}
243 
244 		/* ignore this interface if it isn't up and running: */
245 		if ((ifa->ifa_flags & (IFF_UP | IFF_RUNNING)) !=
246 		    (IFF_UP | IFF_RUNNING)) {
247 			continue;
248 		}
249 		/* if we don't have an interface yet, take this one depending
250 		 * on whether the user asked for an interface by name or not.
251 		 * if he did, and this is it, take this one.  if he didn't,
252 		 * and this isn't a loopback interface, take this one: */
253 		if (ifa_user == NULL
254 		    && (ifr_name_user != NULL
255 			? !strcmp(ifa->ifa_name, ifr_name_user)
256 			: !(ifa->ifa_flags & IFF_LOOPBACK))) {
257 			ifa_user = ifa;
258 		}
259 	}
260 
261 	if (ifa == NULL)
262 		errno = ENOENT;
263 
264 	/* if we don't have an interface to return: */
265 	if (ifa_user == NULL) {
266 		freeifaddrs(ifap);
267 		return (NULL);
268 	}
269 	/* start the interface description: */
270 	interface = ndbootd_new0(struct ndbootd_interface, 1);
271 
272 #ifdef HAVE_AF_LINK
273 
274 	/* we must be able to find an AF_LINK ifreq that gives us the
275 	 * interface's Ethernet address. */
276 	for (ifa = ifap; ifa; ifa = ifa->ifa_next) {
277 		if (!strcmp(link_ifas[link_ifas_i]->ifa_name,
278 		    ifa_user->ifa_name)) {
279 			ifa = link_ifas[link_ifas_i];
280 			break;
281 		}
282 	}
283 	if (ifa == NULL) {
284 		freeifaddrs(ifap);
285 		free(interface);
286 		return (NULL);
287 	}
288 	/* copy out the Ethernet address: */
289 	sadl = (struct sockaddr_dl *)ifa->ifa_addr;
290 	memcpy(interface->ndbootd_interface_ether, LLADDR(sadl), sadl->sdl_alen);
291 
292 #else				/* !HAVE_AF_LINK */
293 #error "must have AF_LINK for now"
294 #endif				/* !HAVE_AF_LINK */
295 
296 	/* finish this interface and return it: */
297 	strlcpy(ifr.ifr_name, ifa_user->ifa_name, sizeof(ifr.ifr_name));
298 	assert(sizeof(ifr.ifr_addr) >= ifa_user->ifa_addr->sa_len);
299 	memcpy(&ifr.ifr_addr, ifa_user->ifa_addr, ifa_user->ifa_addr->sa_len);
300 	interface->ndbootd_interface_ifreq = (struct ifreq *) ndbootd_memdup(&ifr, SIZEOF_IFREQ(&ifr));
301 	interface->ndbootd_interface_fd = -1;
302 	freeifaddrs(ifap);
303 	return (interface);
304 }
305 
306 int
307 main(int argc, char *argv[])
308 {
309 	int argv_i;
310 	int show_usage;
311 	const char *interface_name;
312 	const char *boot1_file_name;
313 	const char *boot2_x_name;
314 	char *boot2_file_name;
315 	int boot2_x_name_is_dir;
316 	time_t last_open_time;
317 	int boot1_fd;
318 	int boot2_fd;
319 	time_t last_rarp_time;
320 	char last_client_ether[ETHER_ADDR_LEN];
321 	struct in_addr last_client_ip;
322 	struct stat stat_buffer;
323 	int32_t boot1_block_count;
324 	int32_t boot2_block_count;
325 	size_t boot1_byte_count;
326 	size_t boot2_byte_count;
327 	ssize_t byte_count_read;
328 	struct ndbootd_interface *interface;
329 	char pid_buffer[(sizeof(pid_t) * 3) + 2];
330 	unsigned char packet_buffer[sizeof(struct ether_header) + IP_MAXPACKET];
331 	unsigned char disk_buffer[NDBOOT_MAX_BYTE_COUNT];
332 	char hostname_buffer[MAXHOSTNAMELEN + 1];
333 	struct hostent *the_hostent;
334 	ssize_t packet_length;
335 	time_t now;
336 	struct ether_header *ether_packet;
337 	struct ip *ip_packet;
338 	struct ndboot_packet *nd_packet;
339 #ifdef HAVE_STRICT_ALIGNMENT
340 	struct ether_header ether_packet_buffer;
341 	unsigned char ip_packet_buffer[IP_MAXPACKET];
342 	struct ndboot_packet nd_packet_buffer;
343 #endif				/* HAVE_STRICT_ALIGNMENT */
344 	int nd_window_size;
345 	int nd_window_filled;
346 	off_t file_offset;
347 	size_t disk_buffer_offset;
348 	size_t block_number;
349 	size_t byte_offset;
350 	ssize_t byte_count;
351 	ssize_t byte_count_wanted;
352 	struct timespec send_delay;
353 	int fd;
354 
355 	/* check our command line: */
356 	if ((_ndbootd_argv0 = strrchr(argv[0], '/')) == NULL)
357 		_ndbootd_argv0 = argv[0];
358 	else
359 		_ndbootd_argv0++;
360 	show_usage = FALSE;
361 #ifdef _NDBOOTD_DO_DEBUG
362 	_ndbootd_debug = FALSE;
363 #endif				/* _NDBOOTD_DO_DEBUG */
364 	boot1_file_name = NULL;
365 	boot2_x_name = NULL;
366 	interface_name = NULL;
367 	nd_window_size = NDBOOT_WINDOW_SIZE_DEFAULT;
368 	for (argv_i = 1; argv_i < argc; argv_i++) {
369 		if (argv[argv_i][0] != '-'
370 		    || argv[argv_i][1] == '\0') {
371 			break;
372 		} else if (!strcmp(argv[argv_i], "-s")
373 		    || !strcmp(argv[argv_i], "--boot2")) {
374 			if (++argv_i < argc) {
375 				boot2_x_name = argv[argv_i];
376 			} else {
377 				show_usage = TRUE;
378 				break;
379 			}
380 		} else if (!strcmp(argv[argv_i], "-i")
381 		    || !strcmp(argv[argv_i], "--interface")) {
382 			if (++argv_i < argc) {
383 				interface_name = argv[argv_i];
384 			} else {
385 				show_usage = TRUE;
386 				break;
387 			}
388 		} else if (!strcmp(argv[argv_i], "-w")
389 		    || !strcmp(argv[argv_i], "--window-size")) {
390 			if (++argv_i == argc || (nd_window_size = atoi(argv[argv_i])) <= 0) {
391 				show_usage = TRUE;
392 				break;
393 			}
394 		}
395 #ifdef _NDBOOTD_DO_DEBUG
396 		else if (!strcmp(argv[argv_i], "-d")
397 		    || !strcmp(argv[argv_i], "--debug")) {
398 			_ndbootd_debug = TRUE;
399 		}
400 #endif				/* _NDBOOTD_DO_DEBUG */
401 		else {
402 			if (strcmp(argv[argv_i], "-h")
403 			    && strcmp(argv[argv_i], "--help")) {
404 				fprintf(stderr, "%s error: unknown switch '%s'\n",
405 				    _ndbootd_argv0, argv[argv_i]);
406 			}
407 			show_usage = TRUE;
408 			break;
409 		}
410 	}
411 	if (argv_i + 1 == argc) {
412 		boot1_file_name = argv[argv_i];
413 	} else {
414 		show_usage = TRUE;
415 	}
416 
417 	if (show_usage) {
418 		fprintf(stderr, "\
419 usage: %s [OPTIONS] BOOT1-BIN\n\
420 where OPTIONS are:\n\
421   -s, --boot2 { BOOT2-BIN | DIR }\n\
422                           find a second-stage boot program in the file\n\
423                           BOOT2-BIN or in the directory DIR\n\
424   -i, --interface NAME    use interface NAME\n\
425   -w, --window-size COUNT \n\
426                           send at most COUNT unacknowledged packets [default=%d]\n",
427 		    _ndbootd_argv0,
428 		    NDBOOT_WINDOW_SIZE_DEFAULT);
429 #ifdef _NDBOOTD_DO_DEBUG
430 		fprintf(stderr, "\
431   -d, --debug             set debug mode\n");
432 #endif				/* _NDBOOTD_DO_DEBUG */
433 		exit(1);
434 	}
435 	/* if we have been given a name for the second-stage boot, see if it's
436 	 * a filename or a directory: */
437 	boot2_x_name_is_dir = FALSE;
438 	if (boot2_x_name != NULL) {
439 		if (stat(boot2_x_name, &stat_buffer) < 0) {
440 			fprintf(stderr, "%s error: could not stat %s: %s\n",
441 			    _ndbootd_argv0, boot2_x_name, strerror(errno));
442 			exit(1);
443 		}
444 		if (S_ISDIR(stat_buffer.st_mode)) {
445 			boot2_x_name_is_dir = TRUE;
446 		} else if (!S_ISREG(stat_buffer.st_mode)) {
447 			fprintf(stderr, "%s error: %s is neither a regular file nor a directory\n",
448 			    _ndbootd_argv0, boot2_x_name);
449 			exit(1);
450 		}
451 	}
452 	/* find the interface we will use: */
453 	if ((interface = _ndbootd_find_interface(interface_name)) == NULL) {
454 		fprintf(stderr, "%s error: could not find the interface to use: %s\n",
455 		    _ndbootd_argv0, strerror(errno));
456 		exit(1);
457 	}
458 	_NDBOOTD_DEBUG((fp, "opening interface %s", interface->ndbootd_interface_ifreq->ifr_name));
459 
460 	/* open the network interface: */
461 	if (ndbootd_raw_open(interface)) {
462 		fprintf(stderr, "%s error: could not open the %s interface: %s\n",
463 		    _ndbootd_argv0, interface->ndbootd_interface_ifreq->ifr_name, strerror(errno));
464 		exit(1);
465 	}
466 	_NDBOOTD_DEBUG((fp, "opened interface %s (ip %s ether %02x:%02x:%02x:%02x:%02x:%02x)",
467 		interface->ndbootd_interface_ifreq->ifr_name,
468 		inet_ntoa(((struct sockaddr_in *) & interface->ndbootd_interface_ifreq->ifr_addr)->sin_addr),
469 		((unsigned char *) interface->ndbootd_interface_ether)[0],
470 		((unsigned char *) interface->ndbootd_interface_ether)[1],
471 		((unsigned char *) interface->ndbootd_interface_ether)[2],
472 		((unsigned char *) interface->ndbootd_interface_ether)[3],
473 		((unsigned char *) interface->ndbootd_interface_ether)[4],
474 		((unsigned char *) interface->ndbootd_interface_ether)[5]));
475 
476 	/* become a daemon: */
477 #ifdef _NDBOOTD_DO_DEBUG
478 	if (!_ndbootd_debug)
479 #endif				/* _NDBOOTD_DO_DEBUG */
480 	{
481 
482 		/* fork and exit: */
483 		switch (fork()) {
484 		case 0:
485 			break;
486 		case -1:
487 			fprintf(stderr, "%s error: could not fork: %s\n",
488 			    _ndbootd_argv0, strerror(errno));
489 			exit(1);
490 		default:
491 			exit(0);
492 		}
493 
494 		/* close all file descriptors: */
495 #ifdef HAVE_GETDTABLESIZE
496 		fd = getdtablesize();
497 #else				/* !HAVE_GETDTABLESIZE */
498 		fd = -1;
499 #endif				/* !HAVE_GETDTABLESIZE */
500 		for (; fd >= 0; fd--) {
501 			if (fd != interface->ndbootd_interface_fd) {
502 				close(fd);
503 			}
504 		}
505 
506 #ifdef HAVE_SETSID
507 		/* become our own session: */
508 		setsid();
509 #endif				/* HAVE_SETSID */
510 	}
511 	/* write the pid file: */
512 	if ((fd = open(NDBOOTD_PID_FILE, O_WRONLY | O_CREAT | O_TRUNC, 0644)) >= 0) {
513 		sprintf(pid_buffer, "%u\n", getpid());
514 		write(fd, pid_buffer, strlen(pid_buffer));
515 		close(fd);
516 	}
517 #ifdef HAVE_STRICT_ALIGNMENT
518 	/* we will be dealing with all packet headers in separate buffers, to
519 	 * make sure everything is correctly aligned: */
520 	ether_packet = &ether_packet_buffer;
521 	ip_packet = (struct ip *) & ip_packet_buffer[0];
522 	nd_packet = &nd_packet_buffer;
523 #else				/* !HAVE_STRICT_ALIGNMENT */
524 	/* we will always find the Ethernet header and the IP packet at the
525 	 * front of the buffer: */
526 	ether_packet = (struct ether_header *) packet_buffer;
527 	ip_packet = (struct ip *) (ether_packet + 1);
528 #endif				/* !HAVE_STRICT_ALIGNMENT */
529 
530 	/* initialize our state: */
531 	last_rarp_time = 0;
532 	last_open_time = 0;
533 	boot1_fd = -1;
534 	boot2_file_name = NULL;
535 	boot2_fd = -1;
536 
537 	/* loop processing packets: */
538 	for (;;) {
539 
540 		/* receive another packet: */
541 		packet_length = ndbootd_raw_read(interface, packet_buffer, sizeof(packet_buffer));
542 		if (packet_length < 0) {
543 			_NDBOOTD_DEBUG((fp, "failed to receive packet: %s", strerror(errno)));
544 			exit(1);
545 			continue;
546 		}
547 		now = time(NULL);
548 
549 		/* check the Ethernet and IP parts of the packet: */
550 		if (packet_length
551 		    < (sizeof(struct ether_header)
552 			+ sizeof(struct ip)
553 			+ sizeof(struct ndboot_packet))) {
554 			_NDBOOTD_DEBUG((fp, "ignoring a too-short packet of length %ld", (long) packet_length));
555 			continue;
556 		}
557 #ifdef HAVE_STRICT_ALIGNMENT
558 		memcpy(ether_packet, packet_buffer, sizeof(struct ether_header));
559 		memcpy(ip_packet, packet_buffer + sizeof(struct ether_header),
560 		    (((struct ip *) (packet_buffer + sizeof(struct ether_header)))->ip_hl << 2));
561 #endif				/* !HAVE_STRICT_ALIGNMENT */
562 		if (ether_packet->ether_type != htons(ETHERTYPE_IP)
563 		    || ip_packet->ip_p != IPPROTO_ND) {
564 			_NDBOOTD_DEBUG((fp, "ignoring a packet with the wrong Ethernet or IP protocol"));
565 			continue;
566 		}
567 		_ndbootd_ip_cksum(ip_packet);
568 		if (ip_packet->ip_sum != 0) {
569 			_NDBOOTD_DEBUG((fp, "ignoring a packet with a bad IP checksum"));
570 			continue;
571 		}
572 		if (packet_length
573 		    != (sizeof(struct ether_header)
574 			+ (ip_packet->ip_hl << 2)
575 			+ sizeof(struct ndboot_packet))) {
576 			_NDBOOTD_DEBUG((fp, "ignoring a packet with bad total length %ld", (long) packet_length));
577 			continue;
578 		}
579 		/* if we need to, refresh our RARP cache: */
580 		if ((last_rarp_time + NDBOOTD_CLIENT_TTL_SECONDS) < now
581 		    || memcmp(last_client_ether, ether_packet->ether_shost, ETHER_ADDR_LEN)) {
582 
583 			/* turn the Ethernet address into a hostname: */
584 			if (ether_ntohost(hostname_buffer, (struct ether_addr *) ether_packet->ether_shost)) {
585 				_NDBOOTD_DEBUG((fp, "could not resolve %02x:%02x:%02x:%02x:%02x:%02x into a hostname: %s",
586 					((unsigned char *) ether_packet->ether_shost)[0],
587 					((unsigned char *) ether_packet->ether_shost)[1],
588 					((unsigned char *) ether_packet->ether_shost)[2],
589 					((unsigned char *) ether_packet->ether_shost)[3],
590 					((unsigned char *) ether_packet->ether_shost)[4],
591 					((unsigned char *) ether_packet->ether_shost)[5],
592 					strerror(errno)));
593 				continue;
594 			}
595 			/* turn the hostname into an IP address: */
596 			hostname_buffer[sizeof(hostname_buffer) - 1] = '\0';
597 			if ((the_hostent = gethostbyname(hostname_buffer)) == NULL
598 			    || the_hostent->h_addrtype != AF_INET) {
599 				_NDBOOTD_DEBUG((fp, "could not resolve %s into an IP address: %s",
600 					hostname_buffer,
601 					strerror(errno)));
602 				continue;
603 			}
604 			/* save these new results in our RARP cache: */
605 			last_rarp_time = now;
606 			memcpy(last_client_ether, ether_packet->ether_shost, ETHER_ADDR_LEN);
607 			memcpy(&last_client_ip, the_hostent->h_addr, sizeof(last_client_ip));
608 			_NDBOOTD_DEBUG((fp, "IP address for %02x:%02x:%02x:%02x:%02x:%02x is %s",
609 				((unsigned char *) last_client_ether)[0],
610 				((unsigned char *) last_client_ether)[1],
611 				((unsigned char *) last_client_ether)[2],
612 				((unsigned char *) last_client_ether)[3],
613 				((unsigned char *) last_client_ether)[4],
614 				((unsigned char *) last_client_ether)[5],
615 				inet_ntoa(last_client_ip)));
616 
617 			/* this will cause the file descriptor cache to be
618 			 * reloaded, the next time we make it that far: */
619 			last_open_time = 0;
620 		}
621 		/* if this IP packet was broadcast, rewrite the source IP
622 		 * address to be the client, else, check that the client is
623 		 * using the correct IP addresses: */
624 		if (ip_packet->ip_dst.s_addr == htonl(0)) {
625 			ip_packet->ip_src = last_client_ip;
626 		} else {
627 			if (ip_packet->ip_src.s_addr !=
628 			    last_client_ip.s_addr) {
629 				_NDBOOTD_DEBUG((fp, "machine %02x:%02x:%02x:%02x:%02x:%02x is using the wrong IP address\n",
630 					((unsigned char *) ether_packet->ether_shost)[0],
631 					((unsigned char *) ether_packet->ether_shost)[1],
632 					((unsigned char *) ether_packet->ether_shost)[2],
633 					((unsigned char *) ether_packet->ether_shost)[3],
634 					((unsigned char *) ether_packet->ether_shost)[4],
635 					((unsigned char *) ether_packet->ether_shost)[5]));
636 				continue;
637 			}
638 			if (ip_packet->ip_dst.s_addr
639 			    != ((struct sockaddr_in *) & interface->ndbootd_interface_ifreq->ifr_addr)->sin_addr.s_addr) {
640 				_NDBOOTD_DEBUG((fp, "machine %02x:%02x:%02x:%02x:%02x:%02x is sending to the wrong IP address\n",
641 					((unsigned char *) ether_packet->ether_shost)[0],
642 					((unsigned char *) ether_packet->ether_shost)[1],
643 					((unsigned char *) ether_packet->ether_shost)[2],
644 					((unsigned char *) ether_packet->ether_shost)[3],
645 					((unsigned char *) ether_packet->ether_shost)[4],
646 					((unsigned char *) ether_packet->ether_shost)[5]));
647 				continue;
648 			}
649 		}
650 
651 		/* if we need to, refresh our "cache" of file descriptors for
652 		 * the boot programs: */
653 		if ((last_open_time + NDBOOTD_CLIENT_TTL_SECONDS) < now) {
654 
655 			/* close any previously opened programs: */
656 			if (boot1_fd >= 0) {
657 				close(boot1_fd);
658 			}
659 			if (boot2_file_name != NULL) {
660 				free(boot2_file_name);
661 			}
662 			if (boot2_fd >= 0) {
663 				close(boot2_fd);
664 			}
665 			/* open the first-stage boot program: */
666 			if ((boot1_fd = open(boot1_file_name, O_RDONLY)) < 0) {
667 				_NDBOOTD_DEBUG((fp, "could not open %s: %s",
668 					boot1_file_name, strerror(errno)));
669 				continue;
670 			}
671 			if (fstat(boot1_fd, &stat_buffer) < 0) {
672 				_NDBOOTD_DEBUG((fp, "could not stat %s: %s",
673 					boot1_file_name, strerror(errno)));
674 				continue;
675 			}
676 			boot1_byte_count = stat_buffer.st_size;
677 			boot1_block_count = (boot1_byte_count + (NDBOOT_BSIZE - 1)) / NDBOOT_BSIZE;
678 			if (boot1_block_count > NDBOOTD_BOOT1_BLOCK_COUNT) {
679 				_NDBOOTD_DEBUG((fp, "first-stage boot program %s has too many blocks (%d, max is %d)",
680 					boot1_file_name, boot1_block_count, NDBOOTD_BOOT1_BLOCK_COUNT));
681 			}
682 			_NDBOOTD_DEBUG((fp, "first-stage boot program %s has %d blocks",
683 				boot1_file_name, boot1_block_count));
684 
685 			/* open any second-stage boot program: */
686 			if (boot2_x_name != NULL) {
687 
688 				/* determine what the name of the second-stage
689 				 * boot program will be: */
690 				if (boot2_x_name_is_dir) {
691 					if ((boot2_file_name = malloc(strlen(boot2_x_name) + strlen("/00000000.SUN2") + 1)) != NULL) {
692 						sprintf(boot2_file_name, "%s/%02X%02X%02X%02X.SUN2",
693 						    boot2_x_name,
694 						    ((unsigned char *) &last_client_ip)[0],
695 						    ((unsigned char *) &last_client_ip)[1],
696 						    ((unsigned char *) &last_client_ip)[2],
697 						    ((unsigned char *) &last_client_ip)[3]);
698 					}
699 				} else {
700 					boot2_file_name = strdup(boot2_x_name);
701 				}
702 				if (boot2_file_name == NULL) {
703 					abort();
704 				}
705 				/* open the second-stage boot program: */
706 				if ((boot2_fd = open(boot2_file_name, O_RDONLY)) < 0) {
707 					_NDBOOTD_DEBUG((fp, "could not open %s: %s",
708 						boot2_file_name, strerror(errno)));
709 					continue;
710 				}
711 				if (fstat(boot2_fd, &stat_buffer) < 0) {
712 					_NDBOOTD_DEBUG((fp, "could not stat %s: %s",
713 						boot2_file_name, strerror(errno)));
714 					continue;
715 				}
716 				boot2_byte_count = stat_buffer.st_size;
717 				boot2_block_count = (boot2_byte_count + (NDBOOT_BSIZE - 1)) / NDBOOT_BSIZE;
718 				_NDBOOTD_DEBUG((fp, "second-stage boot program %s has %d blocks",
719 					boot2_file_name, boot2_block_count));
720 			}
721 			/* success: */
722 			last_open_time = now;
723 		}
724 		/* check the nd packet: */
725 #ifdef HAVE_STRICT_ALIGNMENT
726 		memcpy(nd_packet, packet_buffer + sizeof(struct ether_header) + (ip_packet->ip_hl << 2), sizeof(struct ndboot_packet));
727 #else				/* !HAVE_STRICT_ALIGNMENT */
728 		nd_packet = (struct ndboot_packet *) (((char *) ip_packet) + (ip_packet->ip_hl << 2));
729 #endif				/* !HAVE_STRICT_ALIGNMENT */
730 
731 		/* dump a bunch of debug information: */
732 		_NDBOOTD_DEBUG((fp, "recv: op 0x%02x minor 0x%02x error %d vers %d seq %d blk %d bcount %d off %d count %d",
733 			nd_packet->ndboot_packet_op,
734 			nd_packet->ndboot_packet_minor,
735 			nd_packet->ndboot_packet_error,
736 			nd_packet->ndboot_packet_disk_version,
737 			(int) ntohl(nd_packet->ndboot_packet_sequence),
738 			(int) ntohl(nd_packet->ndboot_packet_block_number),
739 			(int) ntohl(nd_packet->ndboot_packet_byte_count),
740 			(int) ntohl(nd_packet->ndboot_packet_current_byte_offset),
741 			(int) ntohl(nd_packet->ndboot_packet_current_byte_count)));
742 
743 		/* ignore this packet if it has a bad opcode, a bad minor
744 		 * number, a bad disk version, a bad block number, a bad byte
745 		 * count, a bad current byte offset, or a bad current byte
746 		 * count: */
747 		/* FIXME - for some of these conditions, we probably should
748 		 * return an NDBOOT_OP_ERROR packet: */
749 		if ((nd_packet->ndboot_packet_op & NDBOOT_OP_MASK) != NDBOOT_OP_READ) {
750 			_NDBOOTD_DEBUG((fp, "ignoring a packet with bad op %d",
751 				nd_packet->ndboot_packet_op & NDBOOT_OP_MASK));
752 			continue;
753 		}
754 		if (nd_packet->ndboot_packet_minor != NDBOOT_MINOR_NDP0) {
755 			_NDBOOTD_DEBUG((fp, "ignoring a packet with device minor %d",
756 				nd_packet->ndboot_packet_minor));
757 			continue;
758 		}
759 		if (nd_packet->ndboot_packet_disk_version != 0) {
760 			_NDBOOTD_DEBUG((fp, "ignoring a packet with disk version %d",
761 				nd_packet->ndboot_packet_disk_version));
762 			continue;
763 		}
764 		if (ntohl(nd_packet->ndboot_packet_block_number) < 0) {
765 			_NDBOOTD_DEBUG((fp, "ignoring a packet with bad block number %d",
766 				(int) ntohl(nd_packet->ndboot_packet_block_number)));
767 			continue;
768 		}
769 		if (ntohl(nd_packet->ndboot_packet_byte_count) <= 0 ||
770 		    ntohl(nd_packet->ndboot_packet_byte_count) > NDBOOT_MAX_BYTE_COUNT) {
771 			_NDBOOTD_DEBUG((fp, "ignoring a packet with bad byte count %d",
772 				(int) ntohl(nd_packet->ndboot_packet_byte_count)));
773 			continue;
774 		}
775 		if (ntohl(nd_packet->ndboot_packet_current_byte_offset) < 0 ||
776 		    ntohl(nd_packet->ndboot_packet_current_byte_offset)
777 		    >= ntohl(nd_packet->ndboot_packet_byte_count)) {
778 			_NDBOOTD_DEBUG((fp, "ignoring a packet with bad current offset %d",
779 				(int) ntohl(nd_packet->ndboot_packet_current_byte_offset)));
780 			continue;
781 		}
782 		if (ntohl(nd_packet->ndboot_packet_current_byte_count) < 0 ||
783 		    ntohl(nd_packet->ndboot_packet_current_byte_count)
784 		    > (ntohl(nd_packet->ndboot_packet_byte_count)
785 			- ntohl(nd_packet->ndboot_packet_current_byte_offset))) {
786 			_NDBOOTD_DEBUG((fp, "ignoring a packet with bad current count %d",
787 				(int) ntohl(nd_packet->ndboot_packet_current_byte_count)));
788 			continue;
789 		}
790 		/* if we were given a current byte count of zero, rewrite it
791 		 * to be the maximum: */
792 		if (ntohl(nd_packet->ndboot_packet_current_byte_count) == 0) {
793 			nd_packet->ndboot_packet_current_byte_count =
794 			    htonl(ntohl(nd_packet->ndboot_packet_byte_count)
795 			    - ntohl(nd_packet->ndboot_packet_current_byte_offset));
796 		}
797 		/* read the data: */
798 		disk_buffer_offset = 0;
799 		block_number = ntohl(nd_packet->ndboot_packet_block_number);
800 		byte_offset = ntohl(nd_packet->ndboot_packet_current_byte_offset);
801 		byte_count = ntohl(nd_packet->ndboot_packet_current_byte_count);
802 		for (; byte_count > 0;) {
803 
804 			/* adjust the current block number and byte offset
805 			 * such that the byte offset is always < NDBOOT_BSIZE: */
806 			block_number += (byte_offset / NDBOOT_BSIZE);
807 			byte_offset = byte_offset % NDBOOT_BSIZE;
808 
809 			/* dispatch on the beginning block number: */
810 			byte_count_read = 0;
811 
812 			/* the (dummy) Sun disk label: */
813 			if (block_number >= NDBOOTD_SUNDK_BLOCK_FIRST
814 			    && block_number < (NDBOOTD_SUNDK_BLOCK_FIRST + NDBOOTD_SUNDK_BLOCK_COUNT)) {
815 				byte_count_read = MIN(NDBOOTD_BYTES_AVAIL(block_number, byte_offset,
816 					NDBOOTD_SUNDK_BLOCK_FIRST, NDBOOTD_SUNDK_BLOCK_COUNT),
817 				    byte_count);
818 			}
819 			/* the first-stage boot program: */
820 			else if (block_number >= NDBOOTD_BOOT1_BLOCK_FIRST
821 			    && block_number < (NDBOOTD_BOOT1_BLOCK_FIRST + NDBOOTD_BOOT1_BLOCK_COUNT)) {
822 
823 				/* if any real part of the first-stage boot
824 				 * program is needed to satisfy the request,
825 				 * read it (otherwise we return garbage as
826 				 * padding): */
827 				byte_count_wanted = MIN(NDBOOTD_BYTES_AVAIL(block_number, byte_offset,
828 					NDBOOTD_BOOT1_BLOCK_FIRST, boot1_block_count),
829 				    byte_count);
830 				if (byte_count_wanted > 0) {
831 
832 					file_offset = ((block_number - NDBOOTD_BOOT1_BLOCK_FIRST) * NDBOOT_BSIZE) + byte_offset;
833 					if (lseek(boot1_fd, file_offset, SEEK_SET) < 0) {
834 						_NDBOOTD_DEBUG((fp, "could not seek %s to block %ld offset %ld: %s",
835 							boot1_file_name,
836 							(long) (block_number - NDBOOTD_BOOT1_BLOCK_FIRST),
837 							(long) byte_offset,
838 							strerror(errno)));
839 						break;
840 					}
841 					byte_count_read = read(boot1_fd, disk_buffer + disk_buffer_offset, byte_count_wanted);
842 					/* pretend that the size of the
843 					 * first-stage boot program is a
844 					 * multiple of NDBOOT_BSIZE: */
845 					if (byte_count_read != byte_count_wanted
846 					    && byte_count_read > 0
847 					    && file_offset + byte_count_read == boot1_byte_count) {
848 						byte_count_read = byte_count_wanted;
849 					}
850 					if (byte_count_read != byte_count_wanted) {
851 						_NDBOOTD_DEBUG((fp, "could not read %ld bytes at block %ld offset %ld from %s: %s (read %ld bytes)",
852 							(long) byte_count_wanted,
853 							(long) (block_number - NDBOOTD_BOOT1_BLOCK_FIRST),
854 							(long) byte_offset,
855 							boot1_file_name,
856 							strerror(errno),
857 							(long) byte_count_read));
858 						break;
859 					}
860 				}
861 				/* the number of bytes we read, including any
862 				 * padding garbage: */
863 				byte_count_read = MIN(NDBOOTD_BYTES_AVAIL(block_number, byte_offset,
864 					NDBOOTD_BOOT1_BLOCK_FIRST, NDBOOTD_BOOT1_BLOCK_COUNT),
865 				    byte_count);
866 			}
867 			/* any second-stage boot program: */
868 			else if (block_number >= NDBOOTD_BOOT2_BLOCK_FIRST) {
869 
870 				/* if any real part of any first-stage boot
871 				 * program is needed to satisfy the request,
872 				 * read it (otherwise we return garbage as
873 				 * padding): */
874 				byte_count_wanted = MIN(NDBOOTD_BYTES_AVAIL(block_number, byte_offset,
875 					NDBOOTD_BOOT2_BLOCK_FIRST, boot2_block_count),
876 				    byte_count);
877 				if (boot2_fd >= 0
878 				    && byte_count_wanted > 0) {
879 
880 					file_offset = ((block_number - NDBOOTD_BOOT2_BLOCK_FIRST) * NDBOOT_BSIZE) + byte_offset;
881 					if (lseek(boot2_fd, file_offset, SEEK_SET) < 0) {
882 						_NDBOOTD_DEBUG((fp, "could not seek %s to block %ld offset %ld: %s",
883 							boot2_file_name,
884 							(long) (block_number - NDBOOTD_BOOT2_BLOCK_FIRST),
885 							(long) byte_offset,
886 							strerror(errno)));
887 						break;
888 					}
889 					byte_count_read = read(boot2_fd, disk_buffer + disk_buffer_offset, byte_count_wanted);
890 					/* pretend that the size of the
891 					 * second-stage boot program is a
892 					 * multiple of NDBOOT_BSIZE: */
893 					if (byte_count_read != byte_count_wanted
894 					    && byte_count_read > 0
895 					    && file_offset + byte_count_read == boot2_byte_count) {
896 						byte_count_read = byte_count_wanted;
897 					}
898 					if (byte_count_read != byte_count_wanted) {
899 						_NDBOOTD_DEBUG((fp, "could not read %ld bytes at block %ld offset %ld from %s: %s (read %ld bytes)",
900 							(long) byte_count_wanted,
901 							(long) (block_number - NDBOOTD_BOOT2_BLOCK_FIRST),
902 							(long) byte_offset,
903 							boot2_file_name,
904 							strerror(errno),
905 							(long) byte_count_read));
906 						break;
907 					}
908 				}
909 				/* the number of bytes we read, including any
910 				 * padding garbage: */
911 				byte_count_read = byte_count;
912 			}
913 			/* update for the amount that we read: */
914 			assert(byte_count_read > 0);
915 			disk_buffer_offset += byte_count_read;
916 			byte_offset += byte_count_read;
917 			byte_count -= byte_count_read;
918 		}
919 		if (byte_count > 0) {
920 			/* an error occurred: */
921 			continue;
922 		}
923 		/* set the Ethernet and IP destination and source addresses,
924 		 * and the IP TTL: */
925 		memcpy(ether_packet->ether_dhost, ether_packet->ether_shost, ETHER_ADDR_LEN);
926 		memcpy(ether_packet->ether_shost, interface->ndbootd_interface_ether, ETHER_ADDR_LEN);
927 #ifdef HAVE_STRICT_ALIGNMENT
928 		memcpy(packet_buffer, ether_packet, sizeof(struct ether_header));
929 #endif				/* !HAVE_STRICT_ALIGNMENT */
930 		ip_packet->ip_dst = ip_packet->ip_src;
931 		ip_packet->ip_src = ((struct sockaddr_in *) & interface->ndbootd_interface_ifreq->ifr_addr)->sin_addr;
932 		ip_packet->ip_ttl = 4;
933 
934 		/* return the data: */
935 		nd_window_filled = 0;
936 		disk_buffer_offset = 0;
937 		byte_count = ntohl(nd_packet->ndboot_packet_current_byte_count);
938 		for (;;) {
939 
940 			/* set the byte count on this packet: */
941 			nd_packet->ndboot_packet_current_byte_count = htonl(MIN(byte_count, NDBOOT_MAX_PACKET_DATA));
942 
943 			/* set our opcode.  the opcode is always
944 			 * NDBOOT_OP_READ, ORed with NDBOOT_OP_FLAG_DONE |
945 			 * NDBOOT_OP_FLAG_WAIT if this packet finishes the
946 			 * request, or ORed with NDBOOT_OP_FLAG_WAIT if this
947 			 * packet fills the window: */
948 			nd_window_filled++;
949 			nd_packet->ndboot_packet_op =
950 			    (NDBOOT_OP_READ
951 			    | ((ntohl(nd_packet->ndboot_packet_current_byte_offset)
952 				    + ntohl(nd_packet->ndboot_packet_current_byte_count))
953 				== ntohl(nd_packet->ndboot_packet_byte_count)
954 				? (NDBOOT_OP_FLAG_DONE
955 				    | NDBOOT_OP_FLAG_WAIT)
956 				: (nd_window_filled == nd_window_size
957 				    ? NDBOOT_OP_FLAG_WAIT
958 				    : 0)));
959 
960 			/* copy the data into the packet: */
961 			memcpy(packet_buffer +
962 			    sizeof(struct ether_header) + (ip_packet->ip_hl << 2) + sizeof(struct ndboot_packet),
963 			    disk_buffer + disk_buffer_offset,
964 			    ntohl(nd_packet->ndboot_packet_current_byte_count));
965 
966 			/* finish the IP packet and calculate the checksum: */
967 			ip_packet->ip_len = htons((ip_packet->ip_hl << 2)
968 			    + sizeof(struct ndboot_packet)
969 			    + ntohl(nd_packet->ndboot_packet_current_byte_count));
970 			ip_packet->ip_sum = 0;
971 			_ndbootd_ip_cksum(ip_packet);
972 
973 #ifdef HAVE_STRICT_ALIGNMENT
974 			memcpy(packet_buffer + sizeof(struct ether_header), ip_packet, ip_packet->ip_hl << 2);
975 			memcpy(packet_buffer + sizeof(struct ether_header) + (ip_packet->ip_hl << 2), nd_packet, sizeof(struct ndboot_packet));
976 #endif				/* !HAVE_STRICT_ALIGNMENT */
977 
978 			/* dump a bunch of debug information: */
979 			_NDBOOTD_DEBUG((fp, "send: op 0x%02x minor 0x%02x error %d vers %d seq %d blk %d bcount %d off %d count %d (win %d)",
980 				nd_packet->ndboot_packet_op,
981 				nd_packet->ndboot_packet_minor,
982 				nd_packet->ndboot_packet_error,
983 				nd_packet->ndboot_packet_disk_version,
984 				(int) ntohl(nd_packet->ndboot_packet_sequence),
985 				(int) ntohl(nd_packet->ndboot_packet_block_number),
986 				(int) ntohl(nd_packet->ndboot_packet_byte_count),
987 				(int) ntohl(nd_packet->ndboot_packet_current_byte_offset),
988 				(int) ntohl(nd_packet->ndboot_packet_current_byte_count),
989 				nd_window_filled - 1));
990 
991 			/* delay before sending the packet: */
992 			send_delay.tv_sec = 0;
993 			send_delay.tv_nsec = NDBOOTD_SEND_DELAY_NSECONDS;
994 			nanosleep(&send_delay, NULL);
995 
996 			/* transmit the packet: */
997 			if (ndbootd_raw_write(interface, packet_buffer,
998 				sizeof(struct ether_header) + (ip_packet->ip_hl << 2) + sizeof(struct ndboot_packet) + ntohl(nd_packet->ndboot_packet_current_byte_count)) < 0) {
999 				_NDBOOTD_DEBUG((fp, "could not write a packet: %s",
1000 					strerror(errno)));
1001 			}
1002 			/* if we set NDBOOT_OP_FLAG_DONE or
1003 			 * NDBOOT_OP_FLAG_WAIT in the packet we just sent,
1004 			 * we're done sending: */
1005 			if (nd_packet->ndboot_packet_op != NDBOOT_OP_READ) {
1006 				break;
1007 			}
1008 			/* advance to the next packet: */
1009 			byte_count -= ntohl(nd_packet->ndboot_packet_current_byte_count);
1010 			disk_buffer_offset += ntohl(nd_packet->ndboot_packet_current_byte_count);
1011 			nd_packet->ndboot_packet_current_byte_offset =
1012 			    htonl(ntohl(nd_packet->ndboot_packet_current_byte_offset)
1013 			    + ntohl(nd_packet->ndboot_packet_current_byte_count));
1014 		}
1015 	}
1016 	/* NOTREACHED */
1017 }
1018 /* the raw Ethernet access code: */
1019 #include "config/ndbootd-bpf.c"
1020