xref: /netbsd-src/usr.sbin/installboot/arch/alpha.c (revision e5c09b191b3a14e8b4648a699077b773caf1ed9b)
1 /*	$NetBSD: alpha.c,v 1.22 2019/05/07 04:35:31 thorpej Exp $	*/
2 
3 /*-
4  * Copyright (c) 2002 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Luke Mewburn of Wasabi Systems.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 /*
33  * Copyright (c) 1999 Ross Harvey.  All rights reserved.
34  *
35  * Redistribution and use in source and binary forms, with or without
36  * modification, are permitted provided that the following conditions
37  * are met:
38  * 1. Redistributions of source code must retain the above copyright
39  *    notice, this list of conditions and the following disclaimer.
40  * 2. Redistributions in binary form must reproduce the above copyright
41  *    notice, this list of conditions and the following disclaimer in the
42  *    documentation and/or other materials provided with the distribution.
43  * 3. All advertising materials mentioning features or use of this software
44  *    must display the following acknowledgement:
45  *      This product includes software developed by Ross Harvey
46  *	for the NetBSD Project.
47  * 4. The name of the author may not be used to endorse or promote products
48  *    derived from this software without specific prior written permission
49  *
50  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
51  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
52  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
53  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
54  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
55  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
56  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
57  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
58  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
59  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
60  */
61 
62 /*
63  * Copyright (c) 1999 Christopher G. Demetriou.  All rights reserved.
64  *
65  * Redistribution and use in source and binary forms, with or without
66  * modification, are permitted provided that the following conditions
67  * are met:
68  * 1. Redistributions of source code must retain the above copyright
69  *    notice, this list of conditions and the following disclaimer.
70  * 2. Redistributions in binary form must reproduce the above copyright
71  *    notice, this list of conditions and the following disclaimer in the
72  *    documentation and/or other materials provided with the distribution.
73  * 3. All advertising materials mentioning features or use of this software
74  *    must display the following acknowledgement:
75  *      This product includes software developed by Christopher G. Demetriou
76  *	for the NetBSD Project.
77  * 4. The name of the author may not be used to endorse or promote products
78  *    derived from this software without specific prior written permission
79  *
80  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
81  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
82  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
83  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
84  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
85  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
86  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
87  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
88  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
89  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
90  */
91 
92 #if HAVE_NBTOOL_CONFIG_H
93 #include "nbtool_config.h"
94 #endif
95 
96 #include <sys/cdefs.h>
97 #if !defined(__lint)
98 __RCSID("$NetBSD: alpha.c,v 1.22 2019/05/07 04:35:31 thorpej Exp $");
99 #endif	/* !__lint */
100 
101 #include <sys/param.h>
102 
103 #include <assert.h>
104 #include <err.h>
105 #include <stddef.h>
106 #include <stdio.h>
107 #include <stdlib.h>
108 #include <string.h>
109 #include <unistd.h>
110 
111 #include "installboot.h"
112 
113 #define	SUN_DKMAGIC	55998		/* XXX: from <dev/sun/disklabel.h> */
114 
115 static void	resum(ib_params *, struct alpha_boot_block * const bb,
116 			uint16_t *bb16);
117 static void	sun_bootstrap(ib_params *, struct alpha_boot_block * const);
118 static void	check_sparc(const struct alpha_boot_block * const,
119 			    const char *);
120 
121 static int alpha_clearboot(ib_params *);
122 static int alpha_setboot(ib_params *);
123 
124 struct ib_mach ib_mach_alpha = {
125 	.name		=	"alpha",
126 	.setboot	=	alpha_setboot,
127 	.clearboot	=	alpha_clearboot,
128 	.editboot	=	no_editboot,
129 	.valid_flags	=	IB_STAGE1START | IB_ALPHASUM | IB_APPEND |
130 				    IB_SUNSUM,
131 };
132 
133 static int
alpha_clearboot(ib_params * params)134 alpha_clearboot(ib_params *params)
135 {
136 	struct alpha_boot_block	bb;
137 	uint64_t		cksum;
138 	ssize_t			rv;
139 
140 	assert(params != NULL);
141 	assert(params->fsfd != -1);
142 	assert(params->filesystem != NULL);
143 	assert(sizeof(struct alpha_boot_block) == ALPHA_BOOT_BLOCK_BLOCKSIZE);
144 
145 	if (params->flags & (IB_STAGE1START | IB_APPEND)) {
146 		warnx("Can't use `-b bno' or `-o append' with `-c'");
147 		return (0);
148 	}
149 
150 	rv = pread(params->fsfd, &bb, sizeof(bb), ALPHA_BOOT_BLOCK_OFFSET);
151 	if (rv == -1) {
152 		warn("Reading `%s'", params->filesystem);
153 		return (0);
154 	} else if (rv != sizeof(bb)) {
155 		warnx("Reading `%s': short read", params->filesystem);
156 		return (0);
157 	}
158 	ALPHA_BOOT_BLOCK_CKSUM(&bb, &cksum);
159 	if (cksum != bb.bb_cksum) {		// XXX check bb_cksum endian?
160 		warnx(
161 	    "Old boot block checksum invalid (was %#llx, calculated %#llx)",
162 		    (unsigned long long)le64toh(bb.bb_cksum),
163 		    (unsigned long long)le64toh(cksum));
164 		warnx("Boot block invalid");
165 		return (0);
166 	}
167 
168 	if (params->flags & IB_VERBOSE) {
169 		printf("Old bootstrap start sector: %llu\n",
170 		    (unsigned long long)le64toh(bb.bb_secstart));
171 		printf("Old bootstrap size:         %llu\n",
172 		    (unsigned long long)le64toh(bb.bb_secsize));
173 		printf("Old bootstrap checksum:     %#llx\n",
174 		    (unsigned long long)le64toh(bb.bb_cksum));
175 	}
176 
177 	bb.bb_secstart = bb.bb_secsize = bb.bb_flags = 0;
178 
179 	ALPHA_BOOT_BLOCK_CKSUM(&bb, &bb.bb_cksum);
180 	if (params->flags & IB_SUNSUM)
181 		sun_bootstrap(params, &bb);
182 
183 	printf("New bootstrap start sector: %llu\n",
184 	    (unsigned long long)le64toh(bb.bb_secstart));
185 	printf("New bootstrap size:         %llu\n",
186 	    (unsigned long long)le64toh(bb.bb_secsize));
187 	printf("New bootstrap checksum:     %#llx\n",
188 	    (unsigned long long)le64toh(bb.bb_cksum));
189 
190 	if (params->flags & IB_VERBOSE)
191 		printf("%slearing boot block\n",
192 		    (params->flags & IB_NOWRITE) ? "Not c" : "C");
193 	if (params->flags & IB_NOWRITE)
194 		return (1);
195 
196 	rv = pwrite(params->fsfd, &bb, sizeof(bb), ALPHA_BOOT_BLOCK_OFFSET);
197 	if (rv == -1) {
198 		warn("Writing `%s'", params->filesystem);
199 		return (0);
200 	} else if (rv != sizeof(bb)) {
201 		warnx("Writing `%s': short write", params->filesystem);
202 		return (0);
203 	}
204 
205 	return (1);
206 }
207 
208 static int
alpha_setboot(ib_params * params)209 alpha_setboot(ib_params *params)
210 {
211 	struct alpha_boot_block	bb;
212 	uint64_t		startblock;
213 	int			retval;
214 	char			*bootstrapbuf;
215 	size_t			bootstrapsize;
216 	ssize_t			rv;
217 
218 	assert(params != NULL);
219 	assert(params->fsfd != -1);
220 	assert(params->filesystem != NULL);
221 	assert(params->s1fd != -1);
222 	assert(params->stage1 != NULL);
223 	assert(sizeof(struct alpha_boot_block) == ALPHA_BOOT_BLOCK_BLOCKSIZE);
224 
225 	retval = 0;
226 	bootstrapbuf = NULL;
227 
228 	/*
229 	 * Allocate a buffer, with space to round up the input file
230 	 * to the next block size boundary, and with space for the boot
231 	 * block.
232 	 */
233 	bootstrapsize = roundup(params->s1stat.st_size,
234 	    ALPHA_BOOT_BLOCK_BLOCKSIZE);
235 
236 	bootstrapbuf = malloc(bootstrapsize);
237 	if (bootstrapbuf == NULL) {
238 		warn("Allocating %lu bytes", (unsigned long) bootstrapsize);
239 		goto done;
240 	}
241 	memset(bootstrapbuf, 0, bootstrapsize);
242 
243 	/* read the file into the buffer */
244 	rv = pread(params->s1fd, bootstrapbuf, params->s1stat.st_size, 0);
245 	if (rv == -1) {
246 		warn("Reading `%s'", params->stage1);
247 		goto done;
248 	} else if (rv != params->s1stat.st_size) {
249 		warnx("Reading `%s': short read", params->stage1);
250 		goto done;
251 	}
252 
253 	rv = pread(params->fsfd, &bb, sizeof(bb), ALPHA_BOOT_BLOCK_OFFSET);
254 	if (rv == -1) {
255 		warn("Reading `%s'", params->filesystem);
256 		goto done;
257 	} else if (rv != sizeof(bb)) {
258 		warnx("Reading `%s': short read", params->filesystem);
259 		goto done;
260 	}
261 
262 	if (params->flags & IB_SUNSUM)
263 		check_sparc(&bb, "Initial");
264 
265 		/* fill in the updated bootstrap fields */
266 	if (params->flags & IB_APPEND) {
267 		struct stat	filesyssb;
268 
269 		if (fstat(params->fsfd, &filesyssb) == -1) {
270 			warn("Examining `%s'", params->filesystem);
271 			goto done;
272 		}
273 		if (!S_ISREG(filesyssb.st_mode)) {
274 			warnx(
275 		    "`%s' must be a regular file to append a bootstrap",
276 			    params->filesystem);
277 			goto done;
278 		}
279 		startblock = howmany(filesyssb.st_size,
280 		    ALPHA_BOOT_BLOCK_BLOCKSIZE);
281 	} else if (params->flags & IB_STAGE1START) {
282 		startblock = params->s1start;
283 	} else {
284 		startblock = ALPHA_BOOT_BLOCK_OFFSET /
285 		    ALPHA_BOOT_BLOCK_BLOCKSIZE + 1;
286 	}
287 
288 	bb.bb_secsize =
289 	    htole64(howmany(params->s1stat.st_size,
290 		ALPHA_BOOT_BLOCK_BLOCKSIZE));
291 	bb.bb_secstart = htole64(startblock);
292 	bb.bb_flags = 0;
293 
294 	ALPHA_BOOT_BLOCK_CKSUM(&bb, &bb.bb_cksum);
295 	if (params->flags & IB_SUNSUM)
296 		sun_bootstrap(params, &bb);
297 
298 	if (params->flags & IB_VERBOSE) {
299 		printf("Bootstrap start sector:  %llu\n",
300 		    (unsigned long long)startblock);
301 		printf("Bootstrap sector count:  %llu\n",
302 		    (unsigned long long)le64toh(bb.bb_secsize));
303 		printf("New boot block checksum: %#llx\n",
304 		    (unsigned long long)le64toh(bb.bb_cksum));
305 		printf("%sriting bootstrap\n",
306 		    (params->flags & IB_NOWRITE) ? "Not w" : "W");
307 	}
308 	if (params->flags & IB_NOWRITE) {
309 		retval = 1;
310 		goto done;
311 	}
312 	rv = pwrite(params->fsfd, bootstrapbuf, bootstrapsize,
313 	     startblock * ALPHA_BOOT_BLOCK_BLOCKSIZE);
314 	if (rv == -1) {
315 		warn("Writing `%s'", params->filesystem);
316 		goto done;
317 	} else if ((size_t)rv != bootstrapsize) {
318 		warnx("Writing `%s': short write", params->filesystem);
319 		goto done;
320 	}
321 
322 	if (params->flags & IB_VERBOSE)
323 		printf("Writing boot block\n");
324 	rv = pwrite(params->fsfd, &bb, sizeof(bb), ALPHA_BOOT_BLOCK_OFFSET);
325 	if (rv == -1) {
326 		warn("Writing `%s'", params->filesystem);
327 		goto done;
328 	} else if (rv != sizeof(bb)) {
329 		warnx("Writing `%s': short write", params->filesystem);
330 		goto done;
331 	} else {
332 		retval = 1;
333 	}
334 
335  done:
336 	if (bootstrapbuf)
337 		free(bootstrapbuf);
338 	return (retval);
339 }
340 
341 
342 /*
343  * The Sun and alpha checksums overlay, and the Sun magic number also
344  * overlays the alpha checksum. If you think you are smart: stop here
345  * and do exercise one: figure out how to salt unimportant uint16_t
346  * words in mid-sector so that the alpha and sparc checksums match,
347  * and so the Sun magic number is embedded in the alpha checksum.
348  *
349  * The last uint64_t in the sector is the alpha arithmetic checksum.
350  * The last uint16_t in the sector is the sun xor checksum.
351  * The penultimate uint16_t in the sector is the sun magic number.
352  *
353  *	A:   511     510     509     508     507     506     505     504
354  *	S:   510     511     508     509     506     507     504     505
355  *	63     :       :       :     32:31     :       :       :       0
356  *	|      :       :       :      \:|      :       :       :       |
357  *	7654321076543210765432107654321076543210765432107654321076543210
358  *	|--  sparc   --||--  sparc   --|
359  *	|-- checksum --||--  magic   --|
360  *	|----------------------- alpha checksum -----------------------|
361  *			1011111011011010
362  *			   b   e   d   a
363  */
364 
365 static void
resum(ib_params * params,struct alpha_boot_block * const bb,uint16_t * bb16)366 resum(ib_params *params, struct alpha_boot_block * const bb, uint16_t *bb16)
367 {
368 	static uint64_t lastsum;
369 
370 	if (bb16 != NULL)
371 		memcpy(bb, bb16, sizeof(*bb));
372 	ALPHA_BOOT_BLOCK_CKSUM(bb, &bb->bb_cksum);
373 	if (bb16 != NULL)
374 		memcpy(bb16, bb, sizeof(*bb));
375 	if ((params->flags & IB_VERBOSE) && lastsum != bb->bb_cksum)
376 		printf("alpha checksum now %016llx\n",
377 		    (unsigned long long)le64toh(bb->bb_cksum));
378 	lastsum = bb->bb_cksum;
379 }
380 
381 static void
sun_bootstrap(ib_params * params,struct alpha_boot_block * const bb)382 sun_bootstrap(ib_params *params, struct alpha_boot_block * const bb)
383 {
384 #	define BB_ADJUST_OFFSET 64
385 	static char our_int16s[] = "\2\3\6\7\12";
386 	uint16_t i, j, chkdelta, sunsum, bb16[256];
387 
388 	/*
389 	 * Theory: the alpha checksum is adjusted so bits 47:32 add up
390 	 * to the Sun magic number. Then, another adjustment is computed
391 	 * so bits 63:48 add up to the Sun checksum, and applied in pieces
392 	 * so it changes the alpha checksum but not the Sun value.
393 	 *
394   	 * Note: using memcpy(3) instead of a union as a strict c89/c9x
395   	 * conformance experiment and to avoid a public interface delta.
396 	 */
397 	assert(sizeof(bb16) == sizeof(*bb));
398 	memcpy(bb16, bb, sizeof(bb16));
399 	for (i = 0; our_int16s[i]; ++i) {
400 		j = BB_ADJUST_OFFSET + our_int16s[i];
401 		if (bb16[j]) {
402 			warnx("Non-zero bits %04x in bytes %d..%d",
403 			    bb16[j], j * 2, j * 2 + 1);
404 			bb16[j] = 0;
405 			resum(params, bb, bb16);
406 		}
407 	}
408 	/*
409 	 * Make alpha checksum <47:32> come out to the sun magic.
410 	 */
411 	bb16[BB_ADJUST_OFFSET + 2] = htobe16(SUN_DKMAGIC) - bb16[254];
412 	resum(params, bb, bb16);
413 	sunsum = compute_sunsum(bb16);		/* might be the final value */
414 	if (params->flags & IB_VERBOSE)
415 		printf("target sun checksum is %04x\n", sunsum);
416 	/*
417 	 * Arrange to have alpha 63:48 add up to the sparc checksum.
418 	 */
419 	chkdelta = sunsum - bb16[255];
420 	bb16[BB_ADJUST_OFFSET + 3] = chkdelta >> 1;
421 	bb16[BB_ADJUST_OFFSET + 7] = chkdelta >> 1;
422 	/*
423 	 * By placing half the correction in two different uint64_t words at
424 	 * positions 63:48, the sparc sum will not change but the alpha sum
425 	 * will have the full correction, but only if the target adjustment
426 	 * was even. If it was odd, reverse propagate the carry one place.
427 	 */
428 	if (chkdelta & 1) {
429 		if (params->flags & IB_VERBOSE)
430 			printf("target adjustment %04x was odd, correcting\n",
431 			    chkdelta);
432 		assert(bb16[BB_ADJUST_OFFSET + 6] == 0);
433 		assert(bb16[BB_ADJUST_OFFSET + 012] == 0);
434 		bb16[BB_ADJUST_OFFSET + 6] += 0x8000;
435 		bb16[BB_ADJUST_OFFSET + 012] += 0x8000;
436 	}
437 	resum(params, bb, bb16);
438 	if (params->flags & IB_VERBOSE)
439 		printf("final harmonized checksum: %016llx\n",
440 		    (unsigned long long)le64toh(bb->bb_cksum));
441 	check_sparc(bb, "Final");
442 }
443 
444 static void
check_sparc(const struct alpha_boot_block * const bb,const char * when)445 check_sparc(const struct alpha_boot_block * const bb, const char *when)
446 {
447 	uint16_t bb16[256];
448 #define wmsg "%s sparc %s 0x%04x invalid, expected 0x%04x"
449 
450 	memcpy(bb16, bb, sizeof(bb16));
451 	if (compute_sunsum(bb16) != bb16[255])
452 		warnx(wmsg, when, "checksum", bb16[255], compute_sunsum(bb16));
453 	if (bb16[254] != htobe16(SUN_DKMAGIC))
454 		warnx(wmsg, when, "magic number", bb16[254],
455 		    htobe16(SUN_DKMAGIC));
456 }
457