i386.c revision 1.20 1 /* $NetBSD: i386.c,v 1.20 2006/01/24 18:35:18 dsl Exp $ */
2
3 /*-
4 * Copyright (c) 2003 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by David Laight.
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 * 3. All advertising materials mentioning features or use of this software
19 * must display the following acknowledgement:
20 * This product includes software developed by the NetBSD
21 * Foundation, Inc. and its contributors.
22 * 4. Neither the name of The NetBSD Foundation nor the names of its
23 * contributors may be used to endorse or promote products derived
24 * from this software without specific prior written permission.
25 *
26 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36 * POSSIBILITY OF SUCH DAMAGE.
37 */
38
39 #if HAVE_NBTOOL_CONFIG_H
40 #include "nbtool_config.h"
41 #endif
42
43 #include <sys/cdefs.h>
44 #if !defined(__lint)
45 __RCSID("$NetBSD: i386.c,v 1.20 2006/01/24 18:35:18 dsl Exp $");
46 #endif /* !__lint */
47
48 #include <sys/param.h>
49
50 #include <assert.h>
51 #include <err.h>
52 #include <md5.h>
53 #include <stddef.h>
54 #include <stdio.h>
55 #include <stdlib.h>
56 #include <string.h>
57 #include <unistd.h>
58
59 #include "installboot.h"
60
61 #define nelem(x) (sizeof (x)/sizeof *(x))
62
63 static const char *const console_names[] = {
64 "pc", "com0", "com1", "com2", "com3",
65 "com0kbd", "com1kbd", "com2kbd", "com3kbd",
66 NULL };
67
68 static void
69 show_i386_boot_params(struct x86_boot_params *bpp)
70 {
71 uint32_t i;
72
73 printf("Boot options: ");
74 printf("timeout %d, ", le32toh(bpp->bp_timeout));
75 printf("flags %x, ", le32toh(bpp->bp_flags));
76 printf("speed %d, ", le32toh(bpp->bp_conspeed));
77 printf("ioaddr %x, ", le32toh(bpp->bp_consaddr));
78 i = le32toh(bpp->bp_consdev);
79 if (i < nelem(console_names) - 1)
80 printf("console %s\n", console_names[i]);
81 else
82 printf("console %d\n", i);
83 if (bpp->bp_keymap[0])
84 printf(" keymap %s\n", bpp->bp_keymap);
85 }
86
87 static int
88 update_i386_boot_params(ib_params *params, struct x86_boot_params *bpp)
89 {
90 struct x86_boot_params bp;
91 int bplen;
92 int i;
93
94 bplen = le32toh(bpp->bp_length);
95 if (bplen > sizeof bp)
96 /* Ignore pad space in bootxx */
97 bplen = sizeof bp;
98
99 /* Take (and update) local copy so we handle size mismatches */
100 memset(&bp, 0, sizeof bp);
101 memcpy(&bp, bpp, bplen);
102
103 if (params->flags & IB_TIMEOUT)
104 bp.bp_timeout = htole32(params->timeout);
105 if (params->flags & IB_RESETVIDEO)
106 bp.bp_flags ^= htole32(X86_BP_FLAGS_RESET_VIDEO);
107 if (params->flags & IB_CONSPEED)
108 bp.bp_conspeed = htole32(params->conspeed);
109 if (params->flags & IB_CONSADDR)
110 bp.bp_consaddr = htole32(params->consaddr);
111 if (params->flags & IB_CONSOLE) {
112 for (i = 0; ; i++) {
113 if (console_names[i] == NULL) {
114 warnx("invalid console name, valid names are:");
115 fprintf(stderr, "\t%s", console_names[0]);
116 for (i = 1; console_names[i] != NULL; i++)
117 fprintf(stderr, ", %s", console_names[i]);
118 fprintf(stderr, "\n");
119 return 1;
120 }
121 if (strcmp(console_names[i], params->console) == 0)
122 break;
123 }
124 bp.bp_consdev = htole32(i);
125 }
126 if (params->flags & IB_PASSWORD) {
127 if (params->password[0]) {
128 MD5_CTX md5ctx;
129 MD5Init(&md5ctx);
130 MD5Update(&md5ctx, params->password,
131 strlen(params->password));
132 MD5Final(bp.bp_password, &md5ctx);
133 bp.bp_flags |= htole32(X86_BP_FLAGS_PASSWORD);
134 } else {
135 memset(&bp.bp_password, 0, sizeof bp.bp_password);
136 bp.bp_flags &= ~htole32(X86_BP_FLAGS_PASSWORD);
137 }
138 }
139 if (params->flags & IB_KEYMAP)
140 strlcpy(bp.bp_keymap, params->keymap, sizeof bp.bp_keymap);
141
142 if (params->flags & (IB_NOWRITE | IB_VERBOSE))
143 show_i386_boot_params(&bp);
144
145 /* Check we aren't trying to set anything we can't save */
146 if (bplen < sizeof bp && memcmp((char *)&bp + bplen,
147 (char *)&bp + bplen + 1,
148 sizeof bp - bplen - 1) != 0) {
149 warnx("Patch area in stage1 bootstrap is too small");
150 return 1;
151 }
152 memcpy(bpp, &bp, bplen);
153 return 0;
154 }
155
156 int
157 i386_setboot(ib_params *params)
158 {
159 int retval, i, bpbsize;
160 uint8_t *bootstrapbuf;
161 u_int bootstrapsize;
162 ssize_t rv;
163 uint32_t magic;
164 struct x86_boot_params *bpp;
165 struct mbr_sector mbr;
166
167 assert(params != NULL);
168 assert(params->fsfd != -1);
169 assert(params->filesystem != NULL);
170 assert(params->s1fd != -1);
171 assert(params->stage1 != NULL);
172
173 retval = 0;
174 bootstrapbuf = NULL;
175
176 /*
177 * There is only 8k of space in a UFSv1 partition (and ustarfs)
178 * so ensure we don't splat over anything important.
179 */
180 if (params->s1stat.st_size > 8192) {
181 warnx("stage1 bootstrap `%s' is larger than 8192 bytes",
182 params->stage1);
183 goto done;
184 }
185
186 /*
187 * Read in the existing MBR.
188 */
189 rv = pread(params->fsfd, &mbr, sizeof(mbr), MBR_BBSECTOR);
190 if (rv == -1) {
191 warn("Reading `%s'", params->filesystem);
192 goto done;
193 } else if (rv != sizeof(mbr)) {
194 warnx("Reading `%s': short read", params->filesystem);
195 goto done;
196 }
197 if (mbr.mbr_magic != le16toh(MBR_MAGIC)) {
198 if (params->flags & IB_VERBOSE) {
199 printf(
200 "Ignoring MBR with invalid magic in sector 0 of `%s'\n",
201 params->filesystem);
202 }
203 memset(&mbr, 0, sizeof(mbr));
204 }
205
206 /*
207 * Allocate a buffer, with space to round up the input file
208 * to the next block size boundary, and with space for the boot
209 * block.
210 */
211 bootstrapsize = roundup(params->s1stat.st_size, 512);
212
213 bootstrapbuf = malloc(bootstrapsize);
214 if (bootstrapbuf == NULL) {
215 warn("Allocating %u bytes", bootstrapsize);
216 goto done;
217 }
218 memset(bootstrapbuf, 0, bootstrapsize);
219
220 /*
221 * Read the file into the buffer.
222 */
223 rv = pread(params->s1fd, bootstrapbuf, params->s1stat.st_size, 0);
224 if (rv == -1) {
225 warn("Reading `%s'", params->stage1);
226 goto done;
227 } else if (rv != params->s1stat.st_size) {
228 warnx("Reading `%s': short read", params->stage1);
229 goto done;
230 }
231
232 magic = *(uint32_t *)(bootstrapbuf + 512 * 2 + 4);
233 if (magic != htole32(X86_BOOT_MAGIC_1)) {
234 warnx("Invalid magic in stage1 bootstrap %x != %x",
235 magic, htole32(X86_BOOT_MAGIC_1));
236 goto done;
237 }
238
239 /*
240 * Determine size of BIOS Parameter Block (BPB) to copy from
241 * original MBR to the temporary buffer by examining the first
242 * few instruction in the new bootblock. Supported values:
243 * eb 3c 90 jmp ENDOF(mbr_bpbFAT16)+1, nop
244 * eb 58 90 jmp ENDOF(mbr_bpbFAT32)+1, nop
245 * (anything else) ; don't preserve
246 */
247 bpbsize = 0;
248 if (bootstrapbuf[0] == 0xeb && bootstrapbuf[2] == 0x90 &&
249 (bootstrapbuf[1] == 0x3c || bootstrapbuf[1] == 0x58))
250 bpbsize = bootstrapbuf[1] + 2 - MBR_BPB_OFFSET;
251
252 /*
253 * Ensure bootxx hasn't got any code or data (i.e, non-zero bytes) in
254 * the partition table.
255 */
256 for (i = 0; i < sizeof(mbr.mbr_parts); i++) {
257 if (*(uint8_t *)(bootstrapbuf + MBR_PART_OFFSET + i) != 0) {
258 warnx(
259 "Partition table has non-zero byte at offset %d in `%s'",
260 MBR_PART_OFFSET + i, params->stage1);
261 goto done;
262 }
263 }
264
265 /*
266 * Copy the BPB and the partition table from the original MBR to the
267 * temporary buffer so that they're written back to the fs.
268 */
269 if (bpbsize != 0) {
270 if (params->flags & IB_VERBOSE)
271 printf("Preserving %d (%#x) bytes of the BPB\n",
272 bpbsize, bpbsize);
273 memcpy(bootstrapbuf + MBR_BPB_OFFSET, &mbr.mbr_bpb, bpbsize);
274 }
275 memcpy(bootstrapbuf + MBR_PART_OFFSET, &mbr.mbr_parts,
276 sizeof(mbr.mbr_parts));
277
278 /*
279 * Fill in any user-specified options into the
280 * struct x86_boot_params
281 * that's 8 bytes in from the start of the third sector.
282 * See sys/arch/i386/stand/bootxx/bootxx.S for more information.
283 */
284 bpp = (void *)(bootstrapbuf + 512 * 2 + 8);
285 if (update_i386_boot_params(params, bpp))
286 goto done;
287
288 if (params->flags & IB_NOWRITE) {
289 retval = 1;
290 goto done;
291 }
292
293 /*
294 * Write MBR code to sector zero.
295 */
296 rv = pwrite(params->fsfd, bootstrapbuf, 512, 0);
297 if (rv == -1) {
298 warn("Writing `%s'", params->filesystem);
299 goto done;
300 } else if (rv != 512) {
301 warnx("Writing `%s': short write", params->filesystem);
302 goto done;
303 }
304
305 /*
306 * Skip disklabel in sector 1 and write bootxx to sectors 2..N.
307 */
308 rv = pwrite(params->fsfd, bootstrapbuf + 512 * 2,
309 bootstrapsize - 512 * 2, 512 * 2);
310 if (rv == -1) {
311 warn("Writing `%s'", params->filesystem);
312 goto done;
313 } else if (rv != bootstrapsize - 512 * 2) {
314 warnx("Writing `%s': short write", params->filesystem);
315 goto done;
316 }
317
318 retval = 1;
319
320 done:
321 if (bootstrapbuf)
322 free(bootstrapbuf);
323 return retval;
324 }
325
326 int
327 i386_editboot(ib_params *params)
328 {
329 int retval;
330 uint8_t buf[512];
331 ssize_t rv;
332 uint32_t magic;
333 uint32_t offset;
334 struct x86_boot_params *bpp;
335
336 assert(params != NULL);
337 assert(params->fsfd != -1);
338 assert(params->filesystem != NULL);
339
340 retval = 0;
341
342 /*
343 * Read in the existing bootstrap.
344 */
345
346 bpp = NULL;
347 for (offset = 0; offset < 4 * 512; offset += 512) {
348 rv = pread(params->fsfd, &buf, sizeof buf, offset);
349 if (rv == -1) {
350 warn("Reading `%s'", params->filesystem);
351 goto done;
352 } else if (rv != sizeof buf) {
353 warnx("Reading `%s': short read", params->filesystem);
354 goto done;
355 }
356
357 magic = *(uint32_t *)(buf + 4) | 0xf;
358 if (magic != htole32(X86_BOOT_MAGIC_1 | 0xf))
359 continue;
360 bpp = (void *)(buf + 8);
361 break;
362 }
363 if (bpp == NULL) {
364 warnx("Invalid magic in stage1 boostrap");
365 goto done;
366 }
367
368 /*
369 * Fill in any user-specified options into the
370 * struct x86_boot_params
371 * that's 8 bytes in from the start of the third sector.
372 * See sys/arch/i386/stand/bootxx/bootxx.S for more information.
373 */
374 if (update_i386_boot_params(params, bpp))
375 goto done;
376
377 if (params->flags & IB_NOWRITE) {
378 retval = 1;
379 goto done;
380 }
381
382 /*
383 * Write boot code back
384 */
385 rv = pwrite(params->fsfd, buf, sizeof buf, offset);
386 if (rv == -1) {
387 warn("Writing `%s'", params->filesystem);
388 goto done;
389 } else if (rv != sizeof buf) {
390 warnx("Writing `%s': short write", params->filesystem);
391 goto done;
392 }
393
394 retval = 1;
395
396 done:
397 return retval;
398 }
399