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biosboot.c revision 1.13 
      1 /*	$NetBSD: biosboot.c,v 1.13 2014/10/02 19:15:21 joerg Exp $ */
      2 
      3 /*
      4  * Copyright (c) 2009 The NetBSD Foundation, Inc.
      5  * All rights reserved.
      6  *
      7  * This code is derived from software contributed to the NetBSD Foundation
      8  * by Mike M. Volokhov. Development of this software was supported by the
      9  * Google Summer of Code program.
     10  * The GSoC project was mentored by Allen Briggs and Joerg Sonnenberger.
     11  *
     12  * Redistribution and use in source and binary forms, with or without
     13  * modification, are permitted provided that the following conditions
     14  * are met:
     15  * 1. Redistributions of source code must retain the above copyright
     16  *    notice, this list of conditions and the following disclaimer.
     17  * 2. Redistributions in binary form must reproduce the above copyright
     18  *    notice, this list of conditions and the following disclaimer in the
     19  *    documentation and/or other materials provided with the distribution.
     20  *
     21  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     22  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     23  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     24  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     25  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     26  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     27  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     28  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     29  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     30  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     31  * POSSIBILITY OF SUCH DAMAGE.
     32  */
     33 
     34 #if HAVE_NBTOOL_CONFIG_H
     35 #include "nbtool_config.h"
     36 #endif
     37 
     38 #include <sys/cdefs.h>
     39 #ifdef __RCSID
     40 __RCSID("$NetBSD: biosboot.c,v 1.13 2014/10/02 19:15:21 joerg Exp $");
     41 #endif
     42 
     43 #include <sys/stat.h>
     44 #include <sys/types.h>
     45 #include <sys/ioctl.h>
     46 #ifndef HAVE_NBTOOL_CONFIG_H
     47 #include <sys/disk.h>
     48 #endif
     49 #include <sys/param.h>
     50 #include <sys/bootblock.h>
     51 
     52 #include <err.h>
     53 #include <fcntl.h>
     54 #include <paths.h>
     55 #include <stddef.h>
     56 #include <stdio.h>
     57 #include <stdlib.h>
     58 #include <string.h>
     59 #include <unistd.h>
     60 
     61 #include "map.h"
     62 #include "gpt.h"
     63 
     64 #define DEFAULT_BOOTDIR		"/usr/mdec"
     65 #define DEFAULT_BOOTCODE	"gptmbr.bin"
     66 
     67 static daddr_t start;
     68 static uint64_t size;
     69 
     70 static char *bootpath;
     71 static unsigned int entry;
     72 static uint8_t *label;
     73 
     74 const char biosbootmsg[] = "biosboot [-c bootcode] [-i index] "
     75 	"[-L label] device ...";
     76 
     77 __dead static void
     78 usage_biosboot(void)
     79 {
     80 	fprintf(stderr, "usage: %s %s\n", getprogname(), biosbootmsg);
     81 	exit(1);
     82 }
     83 
     84 static struct mbr*
     85 read_boot(void)
     86 {
     87 	int bfd, ret = 0;
     88 	struct mbr *buf;
     89 	struct stat st;
     90 
     91 	/* XXX how to do the following better? */
     92 	if (bootpath == NULL) {
     93 		bootpath = strdup(DEFAULT_BOOTDIR "/" DEFAULT_BOOTCODE);
     94 	} else {
     95 		if (strchr(bootpath, '/') == 0) {
     96 			char *p;
     97 			if ((p = strdup(bootpath)) == NULL)
     98 				err(1, "Malloc failed");
     99 			free(bootpath);
    100 			(void)asprintf(&bootpath, "%s/%s", DEFAULT_BOOTDIR, p);
    101 			free(p);
    102 		}
    103 	}
    104 	if (bootpath == NULL)
    105 		err(1, "Malloc failed");
    106 
    107 	if ((buf = malloc((size_t)secsz)) == NULL)
    108 		err(1, "Malloc failed");
    109 
    110 	if ((bfd = open(bootpath, O_RDONLY)) < 0 || fstat(bfd, &st) == -1) {
    111 		warn("%s", bootpath);
    112 		goto fail;
    113 	}
    114 
    115 	if (st.st_size != MBR_DSN_OFFSET) {
    116 		warnx("%s: the bootcode does not match expected size",
    117 			bootpath);
    118 		goto fail;
    119 	}
    120 
    121 	if (read(bfd, buf, st.st_size) != st.st_size) {
    122 		warn("%s", bootpath);
    123 		goto fail;
    124 	}
    125 
    126 	ret++;
    127 
    128     fail:
    129 	if (bfd >= 0)
    130 		close(bfd);
    131 	if (ret == 0) {
    132 		free(buf);
    133 		buf = NULL;
    134 	}
    135 	return buf;
    136 }
    137 
    138 static void
    139 biosboot(int fd)
    140 {
    141 	map_t *gpt, *tpg;
    142 	map_t *tbl, *lbt;
    143 	map_t *mbrmap, *m;
    144 	struct mbr *mbr, *bootcode;
    145 	struct gpt_hdr *hdr;
    146 	struct gpt_ent *ent;
    147 	unsigned int i, j;
    148 
    149 	/*
    150 	 * Parse and validate partition maps
    151 	 */
    152 	gpt = map_find(MAP_TYPE_PRI_GPT_HDR);
    153 	if (gpt == NULL) {
    154 		warnx("%s: error: no primary GPT header; run create or recover",
    155 		    device_name);
    156 		return;
    157 	}
    158 
    159 	tpg = map_find(MAP_TYPE_SEC_GPT_HDR);
    160 	if (tpg == NULL) {
    161 		warnx("%s: error: no secondary GPT header; run recover",
    162 		    device_name);
    163 		return;
    164 	}
    165 
    166 	tbl = map_find(MAP_TYPE_PRI_GPT_TBL);
    167 	lbt = map_find(MAP_TYPE_SEC_GPT_TBL);
    168 	if (tbl == NULL || lbt == NULL) {
    169 		warnx("%s: error: run recover -- trust me", device_name);
    170 		return;
    171 	}
    172 
    173 	mbrmap = map_find(MAP_TYPE_PMBR);
    174 	if (mbrmap == NULL || mbrmap->map_start != 0) {
    175 		warnx("%s: error: no valid Protective MBR found", device_name);
    176 		return;
    177 	}
    178 
    179 	mbr = mbrmap->map_data;
    180 
    181 	/*
    182 	 * Update the boot code
    183 	 */
    184 	if ((bootcode = read_boot()) == NULL) {
    185 		warnx("error reading bootcode");
    186 		return;
    187 	}
    188 	(void)memcpy(&mbr->mbr_code, &bootcode->mbr_code,
    189 		sizeof(mbr->mbr_code));
    190 	free(bootcode);
    191 
    192 	/*
    193 	 * Walk through the GPT and see where we can boot from
    194 	 */
    195 	for (m = map_first(); m != NULL; m = m->map_next) {
    196 		if (m->map_type != MAP_TYPE_GPT_PART || m->map_index < 1)
    197 			continue;
    198 
    199 		ent = m->map_data;
    200 
    201 		/* first, prefer user selection */
    202 		if (entry > 0 && m->map_index == entry)
    203 			break;
    204 
    205 		if (label != NULL)
    206 			if (strcmp((char *)label,
    207 			    (char *)utf16_to_utf8(ent->ent_name)) == 0)
    208 				break;
    209 
    210 		/* next, partition as could be specified by wedge */
    211 		if (entry < 1 && label == NULL && size > 0 &&
    212 		    m->map_start == start && m->map_size == (off_t)size)
    213 			break;
    214 	}
    215 
    216 	if (m == NULL) {
    217 		warnx("error: no bootable partition");
    218 		return;
    219 	}
    220 
    221 	i = m->map_index - 1;
    222 
    223 
    224 	hdr = gpt->map_data;
    225 
    226 	for (j = 0; j < le32toh(hdr->hdr_entries); j++) {
    227 		ent = (void*)((char*)tbl->map_data + j * le32toh(hdr->hdr_entsz));
    228 		ent->ent_attr &= ~GPT_ENT_ATTR_LEGACY_BIOS_BOOTABLE;
    229 	}
    230 
    231 	ent = (void*)((char*)tbl->map_data + i * le32toh(hdr->hdr_entsz));
    232 	ent->ent_attr |= GPT_ENT_ATTR_LEGACY_BIOS_BOOTABLE;
    233 
    234 	hdr->hdr_crc_table = htole32(crc32(tbl->map_data,
    235 	    le32toh(hdr->hdr_entries) * le32toh(hdr->hdr_entsz)));
    236 	hdr->hdr_crc_self = 0;
    237 	hdr->hdr_crc_self = htole32(crc32(hdr, le32toh(hdr->hdr_size)));
    238 
    239 	gpt_write(fd, gpt);
    240 	gpt_write(fd, tbl);
    241 
    242 
    243 	hdr = tpg->map_data;
    244 
    245 	for (j = 0; j < le32toh(hdr->hdr_entries); j++) {
    246 		ent = (void*)((char*)lbt->map_data + j * le32toh(hdr->hdr_entsz));
    247 		ent->ent_attr &= ~GPT_ENT_ATTR_LEGACY_BIOS_BOOTABLE;
    248 	}
    249 
    250 	ent = (void*)((char*)lbt->map_data + i * le32toh(hdr->hdr_entsz));
    251 	ent->ent_attr |= GPT_ENT_ATTR_LEGACY_BIOS_BOOTABLE;
    252 
    253 	hdr->hdr_crc_table = htole32(crc32(lbt->map_data,
    254 	    le32toh(hdr->hdr_entries) * le32toh(hdr->hdr_entsz)));
    255 	hdr->hdr_crc_self = 0;
    256 	hdr->hdr_crc_self = htole32(crc32(hdr, le32toh(hdr->hdr_size)));
    257 
    258 	gpt_write(fd, lbt);
    259 	gpt_write(fd, tpg);
    260 
    261 
    262 	if (gpt_write(fd, mbrmap) == -1) {
    263 		warnx("error: cannot update Protective MBR");
    264 		return;
    265 	}
    266 
    267 	printf("partition %d marked as bootable\n", i + 1);
    268 }
    269 
    270 int
    271 cmd_biosboot(int argc, char *argv[])
    272 {
    273 #ifdef DIOCGWEDGEINFO
    274 	struct dkwedge_info dkw;
    275 #endif
    276 	struct stat sb;
    277 	char devpath[MAXPATHLEN];
    278 	char *dev, *p;
    279 	int ch, fd;
    280 
    281 	while ((ch = getopt(argc, argv, "c:i:L:")) != -1) {
    282 		switch(ch) {
    283 		case 'c':
    284 			if (bootpath != NULL)
    285 				usage_biosboot();
    286 			if ((bootpath = strdup(optarg)) == NULL)
    287 				err(1, "Malloc failed");
    288 			break;
    289 		case 'i':
    290 			if (entry > 0)
    291 				usage_biosboot();
    292 			entry = strtoul(optarg, &p, 10);
    293 			if (*p != 0 || entry < 1)
    294 				usage_biosboot();
    295 			break;
    296 		case 'L':
    297 			if (label != NULL)
    298 				usage_biosboot();
    299 			label = (uint8_t *)strdup(optarg);
    300 			break;
    301 		default:
    302 			usage_biosboot();
    303 		}
    304 	}
    305 
    306 	if (argc == optind)
    307 		usage_biosboot();
    308 
    309 	while (optind < argc) {
    310 		dev = argv[optind++];
    311 		start = 0;
    312 		size = 0;
    313 
    314 		/*
    315 		 * If a dk wedge was specified, loader should be
    316 		 * installed onto parent device
    317 		 */
    318 		if ((fd = opendisk(dev, O_RDONLY, devpath, sizeof(devpath), 0))
    319 				== -1)
    320 			goto next;
    321 		if (fstat(fd, &sb) == -1)
    322 			goto close;
    323 
    324 #ifdef DIOCGWEDGEINFO
    325 		if ((sb.st_mode & S_IFMT) != S_IFREG &&
    326 		    ioctl(fd, DIOCGWEDGEINFO, &dkw) != -1) {
    327 			if (entry > 0)
    328 				/* wedges and indexes are mutually exclusive */
    329 				usage_biosboot();
    330 			dev = dkw.dkw_parent;
    331 			start = dkw.dkw_offset;
    332 			size = dkw.dkw_size;
    333 		}
    334 #endif
    335 	close:
    336 		close(fd);
    337 
    338 		fd = gpt_open(dev);
    339 	next:
    340 		if (fd == -1) {
    341 			warn("unable to open device '%s'", device_name);
    342 			continue;
    343 		}
    344 
    345 		biosboot(fd);
    346 
    347 		gpt_close(fd);
    348 	}
    349 
    350 	return (0);
    351 }
    352