1 /* $NetBSD: boot1.c,v 1.22 2023/06/29 14:18:58 manu 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 * 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 #include <sys/cdefs.h> 33 __RCSID("$NetBSD: boot1.c,v 1.22 2023/06/29 14:18:58 manu Exp $"); 34 35 #include <lib/libsa/stand.h> 36 #include <lib/libkern/libkern.h> 37 #include <biosdisk_ll.h> 38 39 #include <sys/param.h> 40 #include <sys/uuid.h> 41 #include <sys/bootblock.h> 42 #include <sys/disklabel.h> 43 #include <sys/disklabel_gpt.h> 44 #include <dev/raidframe/raidframevar.h> /* For RF_PROTECTED_SECTORS */ 45 46 #define XSTR(x) #x 47 #define STR(x) XSTR(x) 48 49 static daddr_t bios_sector; 50 51 static struct biosdisk_ll d; 52 53 const char *boot1(uint32_t, uint64_t *); 54 #ifndef NO_GPT 55 static daddr_t gpt_lookup(daddr_t); 56 #endif 57 extern void putstr(const char *); 58 59 extern struct disklabel ptn_disklabel; 60 61 static int 62 ob(void) 63 { 64 return open("boot", 0); 65 } 66 67 const char * 68 boot1(uint32_t biosdev, uint64_t *sector) 69 { 70 struct stat sb; 71 int fd; 72 73 bios_sector = *sector; 74 d.dev = biosdev; 75 76 putstr("\r\nNetBSD/x86 " STR(FS) " Primary Bootstrap\r\n"); 77 78 if (set_geometry(&d, NULL)) 79 return "set_geometry\r\n"; 80 81 /* 82 * We default to the filesystem at the start of the 83 * MBR partition 84 */ 85 fd = ob(); 86 if (fd != -1) 87 goto done; 88 /* 89 * Maybe the filesystem is enclosed in a raid set. 90 * add in size of raidframe header and try again. 91 * (Maybe this should only be done if the filesystem 92 * magic number is absent.) 93 */ 94 bios_sector += RF_PROTECTED_SECTORS; 95 fd = ob(); 96 if (fd != -1) 97 goto done; 98 99 #ifndef NO_GPT 100 /* 101 * Test for a GPT inside the RAID 102 */ 103 bios_sector += gpt_lookup(bios_sector); 104 fd = ob(); 105 if (fd != -1) 106 goto done; 107 #endif 108 109 /* 110 * Nothing at the start of the MBR partition, fallback on 111 * partition 'a' from the disklabel in this MBR partition. 112 */ 113 if (ptn_disklabel.d_magic != DISKMAGIC || 114 ptn_disklabel.d_magic2 != DISKMAGIC || 115 ptn_disklabel.d_partitions[0].p_fstype == FS_UNUSED) 116 goto done; 117 bios_sector = ptn_disklabel.d_partitions[0].p_offset; 118 *sector = bios_sector; 119 if (ptn_disklabel.d_partitions[0].p_fstype == FS_RAID) 120 bios_sector += RF_PROTECTED_SECTORS; 121 122 fd = ob(); 123 124 done: 125 if (fd == -1 || fstat(fd, &sb) == -1) 126 return "Can't open /boot\r\n"; 127 128 biosdev = (uint32_t)sb.st_size; 129 #if 0 130 if (biosdev > SECONDARY_MAX_LOAD) 131 return "/boot too large\r\n"; 132 #endif 133 134 if (read(fd, (void *)SECONDARY_LOAD_ADDRESS, biosdev) != biosdev) 135 return "/boot load failed\r\n"; 136 137 if (*(uint32_t *)(SECONDARY_LOAD_ADDRESS + 4) != X86_BOOT_MAGIC_2) 138 return "Invalid /boot file format\r\n"; 139 140 /* We need to jump to the secondary bootstrap in realmode */ 141 return 0; 142 } 143 144 int 145 blkdevstrategy(void *devdata, int flag, daddr_t dblk, size_t size, void *buf, size_t *rsize) 146 { 147 if (flag != F_READ) 148 return EROFS; 149 150 if (size & (BIOSDISK_DEFAULT_SECSIZE - 1)) 151 return EINVAL; 152 153 if (rsize) 154 *rsize = size; 155 156 if (size != 0 && readsects(&d, bios_sector + dblk, 157 size / BIOSDISK_DEFAULT_SECSIZE, 158 buf, 1) != 0) 159 return EIO; 160 161 return 0; 162 } 163 164 #ifndef NO_GPT 165 static int 166 is_unused(struct gpt_ent *ent) 167 { 168 const struct uuid unused = GPT_ENT_TYPE_UNUSED; 169 170 return (memcmp(ent->ent_type, &unused, sizeof(unused)) == 0); 171 } 172 173 static int 174 is_bootable(struct gpt_ent *ent) 175 { 176 /* GPT_ENT_TYPE_NETBSD_RAID omitted as we are already in a RAID */ 177 const struct uuid bootable[] = { 178 GPT_ENT_TYPE_NETBSD_FFS, 179 GPT_ENT_TYPE_NETBSD_LFS, 180 GPT_ENT_TYPE_NETBSD_CCD, 181 GPT_ENT_TYPE_NETBSD_CGD, 182 }; 183 int i; 184 185 for (i = 0; i < sizeof(bootable) / sizeof(*bootable); i++) { 186 if (memcmp(ent->ent_type, &bootable[i], 187 sizeof(struct uuid)) == 0) 188 return 1; 189 } 190 191 return 0; 192 } 193 194 static daddr_t 195 gpt_lookup(daddr_t sector) 196 { 197 char buf[BIOSDISK_DEFAULT_SECSIZE]; 198 struct mbr_sector *pmbr; 199 const char gpt_hdr_sig[] = GPT_HDR_SIG; 200 struct gpt_hdr *hdr; 201 struct gpt_ent *ent; 202 uint32_t nents; 203 uint32_t entsz; 204 uint32_t entries_per_sector; 205 uint32_t sectors_per_entry; 206 uint64_t firstpart_lba = 0; 207 uint64_t bootable_lba = 0; 208 uint64_t bootme_lba = 0; 209 int i, j; 210 211 /* 212 * Look for a PMBR 213 */ 214 if (readsects(&d, sector, 1, buf, 1) != 0) 215 return 0; 216 217 pmbr = (struct mbr_sector *)buf; 218 219 if (pmbr->mbr_magic != htole16(MBR_MAGIC)) 220 return 0; 221 222 if (pmbr->mbr_parts[0].mbrp_type != MBR_PTYPE_PMBR) 223 return 0; 224 225 sector++; /* skip PMBR */ 226 227 /* 228 * Look for a GPT header 229 * Space is scarce, we do not check CRC. 230 */ 231 if (readsects(&d, sector, 1, buf, 1) != 0) 232 return 0; 233 234 hdr = (struct gpt_hdr *)buf; 235 236 if (memcmp(gpt_hdr_sig, hdr->hdr_sig, sizeof(hdr->hdr_sig)) != 0) 237 return 0; 238 239 if (hdr->hdr_revision != htole32(GPT_HDR_REVISION)) 240 return 0; 241 242 if (le32toh(hdr->hdr_size) > BIOSDISK_DEFAULT_SECSIZE) 243 return 0; 244 245 nents = le32toh(hdr->hdr_entries); 246 entsz = le32toh(hdr->hdr_entsz); 247 248 sector++; /* skip GPT header */ 249 250 /* 251 * Read partition table 252 * 253 * According to UEFI specification section 5.3.2, entries 254 * are 128 * (2^n) bytes long. The most common scenario is 255 * 128 bytes (n = 0) where there are 4 entries per sector. 256 * If n > 2, then entries spans multiple sectors, but they 257 * remain sector-aligned. 258 */ 259 entries_per_sector = BIOSDISK_DEFAULT_SECSIZE / entsz; 260 if (entries_per_sector == 0) 261 entries_per_sector = 1; 262 263 sectors_per_entry = entsz / BIOSDISK_DEFAULT_SECSIZE; 264 if (sectors_per_entry == 0) 265 sectors_per_entry = 1; 266 267 for (i = 0; i < nents; i += entries_per_sector) { 268 if (readsects(&d, sector, 1, buf, 1) != 0) 269 return 0; 270 271 sector += sectors_per_entry; 272 273 for (j = 0; j < entries_per_sector; j++) { 274 ent = (struct gpt_ent *)&buf[j * entsz]; 275 276 if (is_unused(ent)) 277 continue; 278 279 /* First bootme wins, we can stop there */ 280 if (ent->ent_attr & GPT_ENT_ATTR_BOOTME) { 281 bootme_lba = le64toh(ent->ent_lba_start); 282 goto out; 283 } 284 285 if (firstpart_lba == 0) 286 firstpart_lba = le64toh(ent->ent_lba_start); 287 288 if (is_bootable(ent) && bootable_lba == 0) 289 bootable_lba = le64toh(ent->ent_lba_start); 290 } 291 } 292 293 out: 294 if (bootme_lba) 295 return bootme_lba; 296 297 if (bootable_lba) 298 return bootable_lba; 299 300 if (firstpart_lba) 301 return firstpart_lba; 302 303 return 0; 304 } 305 #endif /* ! NO_GPT */ 306