sys/geom/part/g_part_gpt.c

   1 /*-
   2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
   3  *
   4  * Copyright (c) 2002, 2005-2007, 2011 Marcel Moolenaar
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  *
  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  *
  17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27  */
  28
  29 #include <sys/cdefs.h>
  30 __FBSDID("$FreeBSD$");
  31
  32 #include <sys/param.h>
  33 #include <sys/bio.h>
  34 #include <sys/diskmbr.h>
  35 #include <sys/gsb_crc32.h>
  36 #include <sys/endian.h>
  37 #include <sys/gpt.h>
  38 #include <sys/kernel.h>
  39 #include <sys/kobj.h>
  40 #include <sys/limits.h>
  41 #include <sys/lock.h>
  42 #include <sys/malloc.h>
  43 #include <sys/mutex.h>
  44 #include <sys/queue.h>
  45 #include <sys/sbuf.h>
  46 #include <sys/systm.h>
  47 #include <sys/sysctl.h>
  48 #include <sys/uuid.h>
  49 #include <geom/geom.h>
  50 #include <geom/geom_int.h>
  51 #include <geom/part/g_part.h>
  52
  53 #include "g_part_if.h"
  54
  55 FEATURE(geom_part_gpt, "GEOM partitioning class for GPT partitions support");
  56
  57 SYSCTL_DECL(_kern_geom_part);
  58 static SYSCTL_NODE(_kern_geom_part, OID_AUTO, gpt,
  59     CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
  60     "GEOM_PART_GPT GUID Partition Table");
  61
  62 static u_int allow_nesting = 0;
  63 SYSCTL_UINT(_kern_geom_part_gpt, OID_AUTO, allow_nesting,
  64     CTLFLAG_RWTUN, &allow_nesting, 0, "Allow GPT to be nested inside other schemes");
  65
  66 CTASSERT(offsetof(struct gpt_hdr, padding) == 92);
  67 CTASSERT(sizeof(struct gpt_ent) == 128);
  68
  69 extern u_int geom_part_check_integrity;
  70
  71 #define EQUUID(a,b)     (memcmp(a, b, sizeof(struct uuid)) == 0)
  72
  73 #define MBRSIZE         512
  74
  75 enum gpt_elt {
  76         GPT_ELT_PRIHDR,
  77         GPT_ELT_PRITBL,
  78         GPT_ELT_SECHDR,
  79         GPT_ELT_SECTBL,
  80         GPT_ELT_COUNT
  81 };
  82
  83 enum gpt_state {
  84         GPT_STATE_UNKNOWN,      /* Not determined. */
  85         GPT_STATE_MISSING,      /* No signature found. */
  86         GPT_STATE_CORRUPT,      /* Checksum mismatch. */
  87         GPT_STATE_INVALID,      /* Nonconformant/invalid. */
  88         GPT_STATE_UNSUPPORTED,  /* Not supported. */
  89         GPT_STATE_OK            /* Perfectly fine. */
  90 };
  91
  92 struct g_part_gpt_table {
  93         struct g_part_table     base;
  94         u_char                  mbr[MBRSIZE];
  95         struct gpt_hdr          *hdr;
  96         quad_t                  lba[GPT_ELT_COUNT];
  97         enum gpt_state          state[GPT_ELT_COUNT];
  98         int                     bootcamp;
  99 };
 100
 101 struct g_part_gpt_entry {
 102         struct g_part_entry     base;
 103         struct gpt_ent          ent;
 104 };
 105
 106 static void g_gpt_printf_utf16(struct sbuf *, uint16_t *, size_t);
 107 static void g_gpt_utf8_to_utf16(const uint8_t *, uint16_t *, size_t);
 108 static void g_gpt_set_defaults(struct g_part_table *, struct g_provider *);
 109
 110 static int g_part_gpt_add(struct g_part_table *, struct g_part_entry *,
 111     struct g_part_parms *);
 112 static int g_part_gpt_bootcode(struct g_part_table *, struct g_part_parms *);
 113 static int g_part_gpt_create(struct g_part_table *, struct g_part_parms *);
 114 static int g_part_gpt_destroy(struct g_part_table *, struct g_part_parms *);
 115 static void g_part_gpt_dumpconf(struct g_part_table *, struct g_part_entry *,
 116     struct sbuf *, const char *);
 117 static int g_part_gpt_dumpto(struct g_part_table *, struct g_part_entry *);
 118 static int g_part_gpt_modify(struct g_part_table *, struct g_part_entry *,
 119     struct g_part_parms *);
 120 static const char *g_part_gpt_name(struct g_part_table *, struct g_part_entry *,
 121     char *, size_t);
 122 static int g_part_gpt_probe(struct g_part_table *, struct g_consumer *);
 123 static int g_part_gpt_read(struct g_part_table *, struct g_consumer *);
 124 static int g_part_gpt_setunset(struct g_part_table *table,
 125     struct g_part_entry *baseentry, const char *attrib, unsigned int set);
 126 static const char *g_part_gpt_type(struct g_part_table *, struct g_part_entry *,
 127     char *, size_t);
 128 static int g_part_gpt_write(struct g_part_table *, struct g_consumer *);
 129 static int g_part_gpt_resize(struct g_part_table *, struct g_part_entry *,
 130     struct g_part_parms *);
 131 static int g_part_gpt_recover(struct g_part_table *);
 132
 133 static kobj_method_t g_part_gpt_methods[] = {
 134         KOBJMETHOD(g_part_add,          g_part_gpt_add),
 135         KOBJMETHOD(g_part_bootcode,     g_part_gpt_bootcode),
 136         KOBJMETHOD(g_part_create,       g_part_gpt_create),
 137         KOBJMETHOD(g_part_destroy,      g_part_gpt_destroy),
 138         KOBJMETHOD(g_part_dumpconf,     g_part_gpt_dumpconf),
 139         KOBJMETHOD(g_part_dumpto,       g_part_gpt_dumpto),
 140         KOBJMETHOD(g_part_modify,       g_part_gpt_modify),
 141         KOBJMETHOD(g_part_resize,       g_part_gpt_resize),
 142         KOBJMETHOD(g_part_name,         g_part_gpt_name),
 143         KOBJMETHOD(g_part_probe,        g_part_gpt_probe),
 144         KOBJMETHOD(g_part_read,         g_part_gpt_read),
 145         KOBJMETHOD(g_part_recover,      g_part_gpt_recover),
 146         KOBJMETHOD(g_part_setunset,     g_part_gpt_setunset),
 147         KOBJMETHOD(g_part_type,         g_part_gpt_type),
 148         KOBJMETHOD(g_part_write,        g_part_gpt_write),
 149         { 0, 0 }
 150 };
 151
 152 #define MAXENTSIZE 1024
 153
 154 static struct g_part_scheme g_part_gpt_scheme = {
 155         "GPT",
 156         g_part_gpt_methods,
 157         sizeof(struct g_part_gpt_table),
 158         .gps_entrysz = sizeof(struct g_part_gpt_entry),
 159         .gps_minent = 128,
 160         .gps_maxent = 4096,
 161         .gps_bootcodesz = MBRSIZE,
 162 };
 163 G_PART_SCHEME_DECLARE(g_part_gpt);
 164 MODULE_VERSION(geom_part_gpt, 0);
 165
 166 static struct uuid gpt_uuid_apple_apfs = GPT_ENT_TYPE_APPLE_APFS;
 167 static struct uuid gpt_uuid_apple_boot = GPT_ENT_TYPE_APPLE_BOOT;
 168 static struct uuid gpt_uuid_apple_core_storage =
 169     GPT_ENT_TYPE_APPLE_CORE_STORAGE;
 170 static struct uuid gpt_uuid_apple_hfs = GPT_ENT_TYPE_APPLE_HFS;
 171 static struct uuid gpt_uuid_apple_label = GPT_ENT_TYPE_APPLE_LABEL;
 172 static struct uuid gpt_uuid_apple_raid = GPT_ENT_TYPE_APPLE_RAID;
 173 static struct uuid gpt_uuid_apple_raid_offline = GPT_ENT_TYPE_APPLE_RAID_OFFLINE;
 174 static struct uuid gpt_uuid_apple_tv_recovery = GPT_ENT_TYPE_APPLE_TV_RECOVERY;
 175 static struct uuid gpt_uuid_apple_ufs = GPT_ENT_TYPE_APPLE_UFS;
 176 static struct uuid gpt_uuid_apple_zfs = GPT_ENT_TYPE_APPLE_ZFS;
 177 static struct uuid gpt_uuid_bios_boot = GPT_ENT_TYPE_BIOS_BOOT;
 178 static struct uuid gpt_uuid_chromeos_firmware = GPT_ENT_TYPE_CHROMEOS_FIRMWARE;
 179 static struct uuid gpt_uuid_chromeos_kernel = GPT_ENT_TYPE_CHROMEOS_KERNEL;
 180 static struct uuid gpt_uuid_chromeos_reserved = GPT_ENT_TYPE_CHROMEOS_RESERVED;
 181 static struct uuid gpt_uuid_chromeos_root = GPT_ENT_TYPE_CHROMEOS_ROOT;
 182 static struct uuid gpt_uuid_dfbsd_ccd = GPT_ENT_TYPE_DRAGONFLY_CCD;
 183 static struct uuid gpt_uuid_dfbsd_hammer = GPT_ENT_TYPE_DRAGONFLY_HAMMER;
 184 static struct uuid gpt_uuid_dfbsd_hammer2 = GPT_ENT_TYPE_DRAGONFLY_HAMMER2;
 185 static struct uuid gpt_uuid_dfbsd_label32 = GPT_ENT_TYPE_DRAGONFLY_LABEL32;
 186 static struct uuid gpt_uuid_dfbsd_label64 = GPT_ENT_TYPE_DRAGONFLY_LABEL64;
 187 static struct uuid gpt_uuid_dfbsd_legacy = GPT_ENT_TYPE_DRAGONFLY_LEGACY;
 188 static struct uuid gpt_uuid_dfbsd_swap = GPT_ENT_TYPE_DRAGONFLY_SWAP;
 189 static struct uuid gpt_uuid_dfbsd_ufs1 = GPT_ENT_TYPE_DRAGONFLY_UFS1;
 190 static struct uuid gpt_uuid_dfbsd_vinum = GPT_ENT_TYPE_DRAGONFLY_VINUM;
 191 static struct uuid gpt_uuid_efi = GPT_ENT_TYPE_EFI;
 192 static struct uuid gpt_uuid_freebsd = GPT_ENT_TYPE_FREEBSD;
 193 static struct uuid gpt_uuid_freebsd_boot = GPT_ENT_TYPE_FREEBSD_BOOT;
 194 static struct uuid gpt_uuid_freebsd_nandfs = GPT_ENT_TYPE_FREEBSD_NANDFS;
 195 static struct uuid gpt_uuid_freebsd_swap = GPT_ENT_TYPE_FREEBSD_SWAP;
 196 static struct uuid gpt_uuid_freebsd_ufs = GPT_ENT_TYPE_FREEBSD_UFS;
 197 static struct uuid gpt_uuid_freebsd_vinum = GPT_ENT_TYPE_FREEBSD_VINUM;
 198 static struct uuid gpt_uuid_freebsd_zfs = GPT_ENT_TYPE_FREEBSD_ZFS;
 199 static struct uuid gpt_uuid_hifive_fsbl = GPT_ENT_TYPE_HIFIVE_FSBL;
 200 static struct uuid gpt_uuid_hifive_bbl = GPT_ENT_TYPE_HIFIVE_BBL;
 201 static struct uuid gpt_uuid_linux_data = GPT_ENT_TYPE_LINUX_DATA;
 202 static struct uuid gpt_uuid_linux_lvm = GPT_ENT_TYPE_LINUX_LVM;
 203 static struct uuid gpt_uuid_linux_raid = GPT_ENT_TYPE_LINUX_RAID;
 204 static struct uuid gpt_uuid_linux_swap = GPT_ENT_TYPE_LINUX_SWAP;
 205 static struct uuid gpt_uuid_mbr = GPT_ENT_TYPE_MBR;
 206 static struct uuid gpt_uuid_ms_basic_data = GPT_ENT_TYPE_MS_BASIC_DATA;
 207 static struct uuid gpt_uuid_ms_ldm_data = GPT_ENT_TYPE_MS_LDM_DATA;
 208 static struct uuid gpt_uuid_ms_ldm_metadata = GPT_ENT_TYPE_MS_LDM_METADATA;
 209 static struct uuid gpt_uuid_ms_recovery = GPT_ENT_TYPE_MS_RECOVERY;
 210 static struct uuid gpt_uuid_ms_reserved = GPT_ENT_TYPE_MS_RESERVED;
 211 static struct uuid gpt_uuid_ms_spaces = GPT_ENT_TYPE_MS_SPACES;
 212 static struct uuid gpt_uuid_netbsd_ccd = GPT_ENT_TYPE_NETBSD_CCD;
 213 static struct uuid gpt_uuid_netbsd_cgd = GPT_ENT_TYPE_NETBSD_CGD;
 214 static struct uuid gpt_uuid_netbsd_ffs = GPT_ENT_TYPE_NETBSD_FFS;
 215 static struct uuid gpt_uuid_netbsd_lfs = GPT_ENT_TYPE_NETBSD_LFS;
 216 static struct uuid gpt_uuid_netbsd_raid = GPT_ENT_TYPE_NETBSD_RAID;
 217 static struct uuid gpt_uuid_netbsd_swap = GPT_ENT_TYPE_NETBSD_SWAP;
 218 static struct uuid gpt_uuid_openbsd_data = GPT_ENT_TYPE_OPENBSD_DATA;
 219 static struct uuid gpt_uuid_prep_boot = GPT_ENT_TYPE_PREP_BOOT;
 220 static struct uuid gpt_uuid_solaris_boot = GPT_ENT_TYPE_SOLARIS_BOOT;
 221 static struct uuid gpt_uuid_solaris_root = GPT_ENT_TYPE_SOLARIS_ROOT;
 222 static struct uuid gpt_uuid_solaris_swap = GPT_ENT_TYPE_SOLARIS_SWAP;
 223 static struct uuid gpt_uuid_solaris_backup = GPT_ENT_TYPE_SOLARIS_BACKUP;
 224 static struct uuid gpt_uuid_solaris_var = GPT_ENT_TYPE_SOLARIS_VAR;
 225 static struct uuid gpt_uuid_solaris_home = GPT_ENT_TYPE_SOLARIS_HOME;
 226 static struct uuid gpt_uuid_solaris_altsec = GPT_ENT_TYPE_SOLARIS_ALTSEC;
 227 static struct uuid gpt_uuid_solaris_reserved = GPT_ENT_TYPE_SOLARIS_RESERVED;
 228 static struct uuid gpt_uuid_unused = GPT_ENT_TYPE_UNUSED;
 229 static struct uuid gpt_uuid_vmfs = GPT_ENT_TYPE_VMFS;
 230 static struct uuid gpt_uuid_vmkdiag = GPT_ENT_TYPE_VMKDIAG;
 231 static struct uuid gpt_uuid_vmreserved = GPT_ENT_TYPE_VMRESERVED;
 232 static struct uuid gpt_uuid_vmvsanhdr = GPT_ENT_TYPE_VMVSANHDR;
 233
 234 static struct g_part_uuid_alias {
 235         struct uuid *uuid;
 236         int alias;
 237         int mbrtype;
 238 } gpt_uuid_alias_match[] = {
 239         { &gpt_uuid_apple_apfs,         G_PART_ALIAS_APPLE_APFS,         0 },
 240         { &gpt_uuid_apple_boot,         G_PART_ALIAS_APPLE_BOOT,         0xab },
 241         { &gpt_uuid_apple_core_storage, G_PART_ALIAS_APPLE_CORE_STORAGE, 0 },
 242         { &gpt_uuid_apple_hfs,          G_PART_ALIAS_APPLE_HFS,          0xaf },
 243         { &gpt_uuid_apple_label,        G_PART_ALIAS_APPLE_LABEL,        0 },
 244         { &gpt_uuid_apple_raid,         G_PART_ALIAS_APPLE_RAID,         0 },
 245         { &gpt_uuid_apple_raid_offline, G_PART_ALIAS_APPLE_RAID_OFFLINE, 0 },
 246         { &gpt_uuid_apple_tv_recovery,  G_PART_ALIAS_APPLE_TV_RECOVERY,  0 },
 247         { &gpt_uuid_apple_ufs,          G_PART_ALIAS_APPLE_UFS,          0 },
 248         { &gpt_uuid_apple_zfs,          G_PART_ALIAS_APPLE_ZFS,          0 },
 249         { &gpt_uuid_bios_boot,          G_PART_ALIAS_BIOS_BOOT,          0 },
 250         { &gpt_uuid_chromeos_firmware,  G_PART_ALIAS_CHROMEOS_FIRMWARE,  0 },
 251         { &gpt_uuid_chromeos_kernel,    G_PART_ALIAS_CHROMEOS_KERNEL,    0 },
 252         { &gpt_uuid_chromeos_reserved,  G_PART_ALIAS_CHROMEOS_RESERVED,  0 },
 253         { &gpt_uuid_chromeos_root,      G_PART_ALIAS_CHROMEOS_ROOT,      0 },
 254         { &gpt_uuid_dfbsd_ccd,          G_PART_ALIAS_DFBSD_CCD,          0 },
 255         { &gpt_uuid_dfbsd_hammer,       G_PART_ALIAS_DFBSD_HAMMER,       0 },
 256         { &gpt_uuid_dfbsd_hammer2,      G_PART_ALIAS_DFBSD_HAMMER2,      0 },
 257         { &gpt_uuid_dfbsd_label32,      G_PART_ALIAS_DFBSD,              0xa5 },
 258         { &gpt_uuid_dfbsd_label64,      G_PART_ALIAS_DFBSD64,            0xa5 },
 259         { &gpt_uuid_dfbsd_legacy,       G_PART_ALIAS_DFBSD_LEGACY,       0 },
 260         { &gpt_uuid_dfbsd_swap,         G_PART_ALIAS_DFBSD_SWAP,         0 },
 261         { &gpt_uuid_dfbsd_ufs1,         G_PART_ALIAS_DFBSD_UFS,          0 },
 262         { &gpt_uuid_dfbsd_vinum,        G_PART_ALIAS_DFBSD_VINUM,        0 },
 263         { &gpt_uuid_efi,                G_PART_ALIAS_EFI,                0xee },
 264         { &gpt_uuid_freebsd,            G_PART_ALIAS_FREEBSD,            0xa5 },
 265         { &gpt_uuid_freebsd_boot,       G_PART_ALIAS_FREEBSD_BOOT,       0 },
 266         { &gpt_uuid_freebsd_nandfs,     G_PART_ALIAS_FREEBSD_NANDFS,     0 },
 267         { &gpt_uuid_freebsd_swap,       G_PART_ALIAS_FREEBSD_SWAP,       0 },
 268         { &gpt_uuid_freebsd_ufs,        G_PART_ALIAS_FREEBSD_UFS,        0 },
 269         { &gpt_uuid_freebsd_vinum,      G_PART_ALIAS_FREEBSD_VINUM,      0 },
 270         { &gpt_uuid_freebsd_zfs,        G_PART_ALIAS_FREEBSD_ZFS,        0 },
 271         { &gpt_uuid_hifive_fsbl,        G_PART_ALIAS_HIFIVE_FSBL,        0 },
 272         { &gpt_uuid_hifive_bbl,         G_PART_ALIAS_HIFIVE_BBL,         0 },
 273         { &gpt_uuid_linux_data,         G_PART_ALIAS_LINUX_DATA,         0x0b },
 274         { &gpt_uuid_linux_lvm,          G_PART_ALIAS_LINUX_LVM,          0 },
 275         { &gpt_uuid_linux_raid,         G_PART_ALIAS_LINUX_RAID,         0 },
 276         { &gpt_uuid_linux_swap,         G_PART_ALIAS_LINUX_SWAP,         0 },
 277         { &gpt_uuid_mbr,                G_PART_ALIAS_MBR,                0 },
 278         { &gpt_uuid_ms_basic_data,      G_PART_ALIAS_MS_BASIC_DATA,      0x0b },
 279         { &gpt_uuid_ms_ldm_data,        G_PART_ALIAS_MS_LDM_DATA,        0 },
 280         { &gpt_uuid_ms_ldm_metadata,    G_PART_ALIAS_MS_LDM_METADATA,    0 },
 281         { &gpt_uuid_ms_recovery,        G_PART_ALIAS_MS_RECOVERY,        0 },
 282         { &gpt_uuid_ms_reserved,        G_PART_ALIAS_MS_RESERVED,        0 },
 283         { &gpt_uuid_ms_spaces,          G_PART_ALIAS_MS_SPACES,          0 },
 284         { &gpt_uuid_netbsd_ccd,         G_PART_ALIAS_NETBSD_CCD,         0 },
 285         { &gpt_uuid_netbsd_cgd,         G_PART_ALIAS_NETBSD_CGD,         0 },
 286         { &gpt_uuid_netbsd_ffs,         G_PART_ALIAS_NETBSD_FFS,         0 },
 287         { &gpt_uuid_netbsd_lfs,         G_PART_ALIAS_NETBSD_LFS,         0 },
 288         { &gpt_uuid_netbsd_raid,        G_PART_ALIAS_NETBSD_RAID,        0 },
 289         { &gpt_uuid_netbsd_swap,        G_PART_ALIAS_NETBSD_SWAP,        0 },
 290         { &gpt_uuid_openbsd_data,       G_PART_ALIAS_OPENBSD_DATA,       0 },
 291         { &gpt_uuid_prep_boot,          G_PART_ALIAS_PREP_BOOT,          0x41 },
 292         { &gpt_uuid_solaris_boot,       G_PART_ALIAS_SOLARIS_BOOT,       0 },
 293         { &gpt_uuid_solaris_root,       G_PART_ALIAS_SOLARIS_ROOT,       0 },
 294         { &gpt_uuid_solaris_swap,       G_PART_ALIAS_SOLARIS_SWAP,       0 },
 295         { &gpt_uuid_solaris_backup,     G_PART_ALIAS_SOLARIS_BACKUP,     0 },
 296         { &gpt_uuid_solaris_var,        G_PART_ALIAS_SOLARIS_VAR,        0 },
 297         { &gpt_uuid_solaris_home,       G_PART_ALIAS_SOLARIS_HOME,       0 },
 298         { &gpt_uuid_solaris_altsec,     G_PART_ALIAS_SOLARIS_ALTSEC,     0 },
 299         { &gpt_uuid_solaris_reserved,   G_PART_ALIAS_SOLARIS_RESERVED,   0 },
 300         { &gpt_uuid_vmfs,               G_PART_ALIAS_VMFS,               0 },
 301         { &gpt_uuid_vmkdiag,            G_PART_ALIAS_VMKDIAG,            0 },
 302         { &gpt_uuid_vmreserved,         G_PART_ALIAS_VMRESERVED,         0 },
 303         { &gpt_uuid_vmvsanhdr,          G_PART_ALIAS_VMVSANHDR,          0 },
 304         { NULL, 0, 0 }
 305 };
 306
 307 static int
 308 gpt_write_mbr_entry(u_char *mbr, int idx, int typ, quad_t start,
 309     quad_t end)
 310 {
 311
 312         if (typ == 0 || start > UINT32_MAX || end > UINT32_MAX)
 313                 return (EINVAL);
 314
 315         mbr += DOSPARTOFF + idx * DOSPARTSIZE;
 316         mbr[0] = 0;
 317         if (start == 1) {
 318                 /*
 319                  * Treat the PMBR partition specially to maximize
 320                  * interoperability with BIOSes.
 321                  */
 322                 mbr[1] = mbr[3] = 0;
 323                 mbr[2] = 2;
 324         } else
 325                 mbr[1] = mbr[2] = mbr[3] = 0xff;
 326         mbr[4] = typ;
 327         mbr[5] = mbr[6] = mbr[7] = 0xff;
 328         le32enc(mbr + 8, (uint32_t)start);
 329         le32enc(mbr + 12, (uint32_t)(end - start + 1));
 330         return (0);
 331 }
 332
 333 static int
 334 gpt_map_type(struct uuid *t)
 335 {
 336         struct g_part_uuid_alias *uap;
 337
 338         for (uap = &gpt_uuid_alias_match[0]; uap->uuid; uap++) {
 339                 if (EQUUID(t, uap->uuid))
 340                         return (uap->mbrtype);
 341         }
 342         return (0);
 343 }
 344
 345 static void
 346 gpt_create_pmbr(struct g_part_gpt_table *table, struct g_provider *pp)
 347 {
 348
 349         bzero(table->mbr + DOSPARTOFF, DOSPARTSIZE * NDOSPART);
 350         gpt_write_mbr_entry(table->mbr, 0, 0xee, 1,
 351             MIN(pp->mediasize / pp->sectorsize - 1, UINT32_MAX));
 352         le16enc(table->mbr + DOSMAGICOFFSET, DOSMAGIC);
 353 }
 354
 355 /*
 356  * Under Boot Camp the PMBR partition (type 0xEE) doesn't cover the
 357  * whole disk anymore. Rather, it covers the GPT table and the EFI
 358  * system partition only. This way the HFS+ partition and any FAT
 359  * partitions can be added to the MBR without creating an overlap.
 360  */
 361 static int
 362 gpt_is_bootcamp(struct g_part_gpt_table *table, const char *provname)
 363 {
 364         uint8_t *p;
 365
 366         p = table->mbr + DOSPARTOFF;
 367         if (p[4] != 0xee || le32dec(p + 8) != 1)
 368                 return (0);
 369
 370         p += DOSPARTSIZE;
 371         if (p[4] != 0xaf)
 372                 return (0);
 373
 374         printf("GEOM: %s: enabling Boot Camp\n", provname);
 375         return (1);
 376 }
 377
 378 static void
 379 gpt_update_bootcamp(struct g_part_table *basetable, struct g_provider *pp)
 380 {
 381         struct g_part_entry *baseentry;
 382         struct g_part_gpt_entry *entry;
 383         struct g_part_gpt_table *table;
 384         int bootable, error, index, slices, typ;
 385
 386         table = (struct g_part_gpt_table *)basetable;
 387
 388         bootable = -1;
 389         for (index = 0; index < NDOSPART; index++) {
 390                 if (table->mbr[DOSPARTOFF + DOSPARTSIZE * index])
 391                         bootable = index;
 392         }
 393
 394         bzero(table->mbr + DOSPARTOFF, DOSPARTSIZE * NDOSPART);
 395         slices = 0;
 396         LIST_FOREACH(baseentry, &basetable->gpt_entry, gpe_entry) {
 397                 if (baseentry->gpe_deleted)
 398                         continue;
 399                 index = baseentry->gpe_index - 1;
 400                 if (index >= NDOSPART)
 401                         continue;
 402
 403                 entry = (struct g_part_gpt_entry *)baseentry;
 404
 405                 switch (index) {
 406                 case 0: /* This must be the EFI system partition. */
 407                         if (!EQUUID(&entry->ent.ent_type, &gpt_uuid_efi))
 408                                 goto disable;
 409                         error = gpt_write_mbr_entry(table->mbr, index, 0xee,
 410                             1ull, entry->ent.ent_lba_end);
 411                         break;
 412                 case 1: /* This must be the HFS+ partition. */
 413                         if (!EQUUID(&entry->ent.ent_type, &gpt_uuid_apple_hfs))
 414                                 goto disable;
 415                         error = gpt_write_mbr_entry(table->mbr, index, 0xaf,
 416                             entry->ent.ent_lba_start, entry->ent.ent_lba_end);
 417                         break;
 418                 default:
 419                         typ = gpt_map_type(&entry->ent.ent_type);
 420                         error = gpt_write_mbr_entry(table->mbr, index, typ,
 421                             entry->ent.ent_lba_start, entry->ent.ent_lba_end);
 422                         break;
 423                 }
 424                 if (error)
 425                         continue;
 426
 427                 if (index == bootable)
 428                         table->mbr[DOSPARTOFF + DOSPARTSIZE * index] = 0x80;
 429                 slices |= 1 << index;
 430         }
 431         if ((slices & 3) == 3)
 432                 return;
 433
 434  disable:
 435         table->bootcamp = 0;
 436         gpt_create_pmbr(table, pp);
 437 }
 438
 439 static struct gpt_hdr *
 440 gpt_read_hdr(struct g_part_gpt_table *table, struct g_consumer *cp,
 441     enum gpt_elt elt)
 442 {
 443         struct gpt_hdr *buf, *hdr;
 444         struct g_provider *pp;
 445         quad_t lba, last;
 446         int error;
 447         uint32_t crc, sz;
 448
 449         pp = cp->provider;
 450         last = (pp->mediasize / pp->sectorsize) - 1;
 451         table->state[elt] = GPT_STATE_MISSING;
 452         /*
 453          * If the primary header is valid look for secondary
 454          * header in AlternateLBA, otherwise in the last medium's LBA.
 455          */
 456         if (elt == GPT_ELT_SECHDR) {
 457                 if (table->state[GPT_ELT_PRIHDR] != GPT_STATE_OK)
 458                         table->lba[elt] = last;
 459         } else
 460                 table->lba[elt] = 1;
 461         buf = g_read_data(cp, table->lba[elt] * pp->sectorsize, pp->sectorsize,
 462             &error);
 463         if (buf == NULL)
 464                 return (NULL);
 465         hdr = NULL;
 466         if (memcmp(buf->hdr_sig, GPT_HDR_SIG, sizeof(buf->hdr_sig)) != 0)
 467                 goto fail;
 468
 469         table->state[elt] = GPT_STATE_CORRUPT;
 470         sz = le32toh(buf->hdr_size);
 471         if (sz < 92 || sz > pp->sectorsize)
 472                 goto fail;
 473
 474         hdr = g_malloc(sz, M_WAITOK | M_ZERO);
 475         bcopy(buf, hdr, sz);
 476         hdr->hdr_size = sz;
 477
 478         crc = le32toh(buf->hdr_crc_self);
 479         buf->hdr_crc_self = 0;
 480         if (crc32(buf, sz) != crc)
 481                 goto fail;
 482         hdr->hdr_crc_self = crc;
 483
 484         table->state[elt] = GPT_STATE_INVALID;
 485         hdr->hdr_revision = le32toh(buf->hdr_revision);
 486         if (hdr->hdr_revision < GPT_HDR_REVISION)
 487                 goto fail;
 488         hdr->hdr_lba_self = le64toh(buf->hdr_lba_self);
 489         if (hdr->hdr_lba_self != table->lba[elt])
 490                 goto fail;
 491         hdr->hdr_lba_alt = le64toh(buf->hdr_lba_alt);
 492         if (hdr->hdr_lba_alt == hdr->hdr_lba_self)
 493                 goto fail;
 494         if (hdr->hdr_lba_alt > last && geom_part_check_integrity)
 495                 goto fail;
 496
 497         /* Check the managed area. */
 498         hdr->hdr_lba_start = le64toh(buf->hdr_lba_start);
 499         if (hdr->hdr_lba_start < 2 || hdr->hdr_lba_start >= last)
 500                 goto fail;
 501         hdr->hdr_lba_end = le64toh(buf->hdr_lba_end);
 502         if (hdr->hdr_lba_end < hdr->hdr_lba_start || hdr->hdr_lba_end >= last)
 503                 goto fail;
 504
 505         /* Check the table location and size of the table. */
 506         hdr->hdr_entries = le32toh(buf->hdr_entries);
 507         hdr->hdr_entsz = le32toh(buf->hdr_entsz);
 508         if (hdr->hdr_entries == 0 || hdr->hdr_entsz < 128 ||
 509             (hdr->hdr_entsz & 7) != 0)
 510                 goto fail;
 511         hdr->hdr_lba_table = le64toh(buf->hdr_lba_table);
 512         if (hdr->hdr_lba_table < 2 || hdr->hdr_lba_table >= last)
 513                 goto fail;
 514         if (hdr->hdr_lba_table >= hdr->hdr_lba_start &&
 515             hdr->hdr_lba_table <= hdr->hdr_lba_end)
 516                 goto fail;
 517         lba = hdr->hdr_lba_table +
 518             howmany((uint64_t)hdr->hdr_entries * hdr->hdr_entsz,
 519                 pp->sectorsize) - 1;
 520         if (lba >= last)
 521                 goto fail;
 522         if (lba >= hdr->hdr_lba_start && lba <= hdr->hdr_lba_end)
 523                 goto fail;
 524
 525         table->state[elt] = GPT_STATE_OK;
 526         le_uuid_dec(&buf->hdr_uuid, &hdr->hdr_uuid);
 527         hdr->hdr_crc_table = le32toh(buf->hdr_crc_table);
 528
 529         /* save LBA for secondary header */
 530         if (elt == GPT_ELT_PRIHDR)
 531                 table->lba[GPT_ELT_SECHDR] = hdr->hdr_lba_alt;
 532
 533         g_free(buf);
 534         return (hdr);
 535
 536  fail:
 537         g_free(hdr);
 538         g_free(buf);
 539         return (NULL);
 540 }
 541
 542 static struct gpt_ent *
 543 gpt_read_tbl(struct g_part_gpt_table *table, struct g_consumer *cp,
 544     enum gpt_elt elt, struct gpt_hdr *hdr)
 545 {
 546         struct g_provider *pp;
 547         struct gpt_ent *ent, *tbl;
 548         char *buf, *p;
 549         unsigned int idx, sectors, tblsz, size;
 550         int error;
 551
 552         if (hdr == NULL)
 553                 return (NULL);
 554         if (hdr->hdr_entries > g_part_gpt_scheme.gps_maxent ||
 555             hdr->hdr_entsz > MAXENTSIZE) {
 556                 table->state[elt] = GPT_STATE_UNSUPPORTED;
 557                 return (NULL);
 558         }
 559
 560         pp = cp->provider;
 561         table->lba[elt] = hdr->hdr_lba_table;
 562
 563         table->state[elt] = GPT_STATE_MISSING;
 564         tblsz = hdr->hdr_entries * hdr->hdr_entsz;
 565         sectors = howmany(tblsz, pp->sectorsize);
 566         buf = g_malloc(sectors * pp->sectorsize, M_WAITOK | M_ZERO);
 567         for (idx = 0; idx < sectors; idx += maxphys / pp->sectorsize) {
 568                 size = (sectors - idx > maxphys / pp->sectorsize) ?  maxphys:
 569                     (sectors - idx) * pp->sectorsize;
 570                 p = g_read_data(cp, (table->lba[elt] + idx) * pp->sectorsize,
 571                     size, &error);
 572                 if (p == NULL) {
 573                         g_free(buf);
 574                         return (NULL);
 575                 }
 576                 bcopy(p, buf + idx * pp->sectorsize, size);
 577                 g_free(p);
 578         }
 579         table->state[elt] = GPT_STATE_CORRUPT;
 580         if (crc32(buf, tblsz) != hdr->hdr_crc_table) {
 581                 g_free(buf);
 582                 return (NULL);
 583         }
 584
 585         table->state[elt] = GPT_STATE_OK;
 586         tbl = g_malloc(hdr->hdr_entries * sizeof(struct gpt_ent),
 587             M_WAITOK | M_ZERO);
 588
 589         for (idx = 0, ent = tbl, p = buf;
 590              idx < hdr->hdr_entries;
 591              idx++, ent++, p += hdr->hdr_entsz) {
 592                 le_uuid_dec(p, &ent->ent_type);
 593                 le_uuid_dec(p + 16, &ent->ent_uuid);
 594                 ent->ent_lba_start = le64dec(p + 32);
 595                 ent->ent_lba_end = le64dec(p + 40);
 596                 ent->ent_attr = le64dec(p + 48);
 597                 /* Keep UTF-16 in little-endian. */
 598                 bcopy(p + 56, ent->ent_name, sizeof(ent->ent_name));
 599         }
 600
 601         g_free(buf);
 602         return (tbl);
 603 }
 604
 605 static int
 606 gpt_matched_hdrs(struct gpt_hdr *pri, struct gpt_hdr *sec)
 607 {
 608
 609         if (pri == NULL || sec == NULL)
 610                 return (0);
 611
 612         if (!EQUUID(&pri->hdr_uuid, &sec->hdr_uuid))
 613                 return (0);
 614         return ((pri->hdr_revision == sec->hdr_revision &&
 615             pri->hdr_size == sec->hdr_size &&
 616             pri->hdr_lba_start == sec->hdr_lba_start &&
 617             pri->hdr_lba_end == sec->hdr_lba_end &&
 618             pri->hdr_entries == sec->hdr_entries &&
 619             pri->hdr_entsz == sec->hdr_entsz &&
 620             pri->hdr_crc_table == sec->hdr_crc_table) ? 1 : 0);
 621 }
 622
 623 static int
 624 gpt_parse_type(const char *type, struct uuid *uuid)
 625 {
 626         struct uuid tmp;
 627         const char *alias;
 628         int error;
 629         struct g_part_uuid_alias *uap;
 630
 631         if (type[0] == '!') {
 632                 error = parse_uuid(type + 1, &tmp);
 633                 if (error)
 634                         return (error);
 635                 if (EQUUID(&tmp, &gpt_uuid_unused))
 636                         return (EINVAL);
 637                 *uuid = tmp;
 638                 return (0);
 639         }
 640         for (uap = &gpt_uuid_alias_match[0]; uap->uuid; uap++) {
 641                 alias = g_part_alias_name(uap->alias);
 642                 if (!strcasecmp(type, alias)) {
 643                         *uuid = *uap->uuid;
 644                         return (0);
 645                 }
 646         }
 647         return (EINVAL);
 648 }
 649
 650 static int
 651 g_part_gpt_add(struct g_part_table *basetable, struct g_part_entry *baseentry,
 652     struct g_part_parms *gpp)
 653 {
 654         struct g_part_gpt_entry *entry;
 655         int error;
 656
 657         entry = (struct g_part_gpt_entry *)baseentry;
 658         error = gpt_parse_type(gpp->gpp_type, &entry->ent.ent_type);
 659         if (error)
 660                 return (error);
 661         kern_uuidgen(&entry->ent.ent_uuid, 1);
 662         entry->ent.ent_lba_start = baseentry->gpe_start;
 663         entry->ent.ent_lba_end = baseentry->gpe_end;
 664         if (baseentry->gpe_deleted) {
 665                 entry->ent.ent_attr = 0;
 666                 bzero(entry->ent.ent_name, sizeof(entry->ent.ent_name));
 667         }
 668         if (gpp->gpp_parms & G_PART_PARM_LABEL)
 669                 g_gpt_utf8_to_utf16(gpp->gpp_label, entry->ent.ent_name,
 670                     sizeof(entry->ent.ent_name) /
 671                     sizeof(entry->ent.ent_name[0]));
 672         return (0);
 673 }
 674
 675 static int
 676 g_part_gpt_bootcode(struct g_part_table *basetable, struct g_part_parms *gpp)
 677 {
 678         struct g_part_gpt_table *table;
 679         size_t codesz;
 680
 681         codesz = DOSPARTOFF;
 682         table = (struct g_part_gpt_table *)basetable;
 683         bzero(table->mbr, codesz);
 684         codesz = MIN(codesz, gpp->gpp_codesize);
 685         if (codesz > 0)
 686                 bcopy(gpp->gpp_codeptr, table->mbr, codesz);
 687         return (0);
 688 }
 689
 690 static int
 691 g_part_gpt_create(struct g_part_table *basetable, struct g_part_parms *gpp)
 692 {
 693         struct g_provider *pp;
 694         struct g_part_gpt_table *table;
 695         size_t tblsz;
 696
 697         /* Our depth should be 0 unless nesting was explicitly enabled. */
 698         if (!allow_nesting && basetable->gpt_depth != 0)
 699                 return (ENXIO);
 700
 701         table = (struct g_part_gpt_table *)basetable;
 702         pp = gpp->gpp_provider;
 703         tblsz = howmany(basetable->gpt_entries * sizeof(struct gpt_ent),
 704             pp->sectorsize);
 705         if (pp->sectorsize < MBRSIZE ||
 706             pp->mediasize < (3 + 2 * tblsz + basetable->gpt_entries) *
 707             pp->sectorsize)
 708                 return (ENOSPC);
 709
 710         gpt_create_pmbr(table, pp);
 711
 712         /* Allocate space for the header */
 713         table->hdr = g_malloc(sizeof(struct gpt_hdr), M_WAITOK | M_ZERO);
 714
 715         bcopy(GPT_HDR_SIG, table->hdr->hdr_sig, sizeof(table->hdr->hdr_sig));
 716         table->hdr->hdr_revision = GPT_HDR_REVISION;
 717         table->hdr->hdr_size = offsetof(struct gpt_hdr, padding);
 718         kern_uuidgen(&table->hdr->hdr_uuid, 1);
 719         table->hdr->hdr_entries = basetable->gpt_entries;
 720         table->hdr->hdr_entsz = sizeof(struct gpt_ent);
 721
 722         g_gpt_set_defaults(basetable, pp);
 723         return (0);
 724 }
 725
 726 static int
 727 g_part_gpt_destroy(struct g_part_table *basetable, struct g_part_parms *gpp)
 728 {
 729         struct g_part_gpt_table *table;
 730         struct g_provider *pp;
 731
 732         table = (struct g_part_gpt_table *)basetable;
 733         pp = LIST_FIRST(&basetable->gpt_gp->consumer)->provider;
 734         g_free(table->hdr);
 735         table->hdr = NULL;
 736
 737         /*
 738          * Wipe the first 2 sectors and last one to clear the partitioning.
 739          * Wipe sectors only if they have valid metadata.
 740          */
 741         if (table->state[GPT_ELT_PRIHDR] == GPT_STATE_OK)
 742                 basetable->gpt_smhead |= 3;
 743         if (table->state[GPT_ELT_SECHDR] == GPT_STATE_OK &&
 744             table->lba[GPT_ELT_SECHDR] == pp->mediasize / pp->sectorsize - 1)
 745                 basetable->gpt_smtail |= 1;
 746         return (0);
 747 }
 748
 749 static void
 750 g_part_gpt_efimedia(struct g_part_gpt_entry *entry, struct sbuf *sb)
 751 {
 752         sbuf_printf(sb, "HD(%d,GPT,", entry->base.gpe_index);
 753         sbuf_printf_uuid(sb, &entry->ent.ent_uuid);
 754         sbuf_printf(sb, ",%#jx,%#jx)", (intmax_t)entry->base.gpe_start,
 755             (intmax_t)(entry->base.gpe_end - entry->base.gpe_start + 1));
 756 }
 757
 758 static void
 759 g_part_gpt_dumpconf(struct g_part_table *table, struct g_part_entry *baseentry,
 760     struct sbuf *sb, const char *indent)
 761 {
 762         struct g_part_gpt_entry *entry;
 763
 764         entry = (struct g_part_gpt_entry *)baseentry;
 765         if (indent == NULL) {
 766                 /* conftxt: libdisk compatibility */
 767                 sbuf_cat(sb, " xs GPT xt ");
 768                 sbuf_printf_uuid(sb, &entry->ent.ent_type);
 769         } else if (entry != NULL) {
 770                 /* confxml: partition entry information */
 771                 sbuf_printf(sb, "%s<label>", indent);
 772                 g_gpt_printf_utf16(sb, entry->ent.ent_name,
 773                     sizeof(entry->ent.ent_name) >> 1);
 774                 sbuf_cat(sb, "</label>\n");
 775                 if (entry->ent.ent_attr & GPT_ENT_ATTR_BOOTME)
 776                         sbuf_printf(sb, "%s<attrib>bootme</attrib>\n", indent);
 777                 if (entry->ent.ent_attr & GPT_ENT_ATTR_BOOTONCE) {
 778                         sbuf_printf(sb, "%s<attrib>bootonce</attrib>\n",
 779                             indent);
 780                 }
 781                 if (entry->ent.ent_attr & GPT_ENT_ATTR_BOOTFAILED) {
 782                         sbuf_printf(sb, "%s<attrib>bootfailed</attrib>\n",
 783                             indent);
 784                 }
 785                 sbuf_printf(sb, "%s<rawtype>", indent);
 786                 sbuf_printf_uuid(sb, &entry->ent.ent_type);
 787                 sbuf_cat(sb, "</rawtype>\n");
 788                 sbuf_printf(sb, "%s<rawuuid>", indent);
 789                 sbuf_printf_uuid(sb, &entry->ent.ent_uuid);
 790                 sbuf_cat(sb, "</rawuuid>\n");
 791                 sbuf_printf(sb, "%s<efimedia>", indent);
 792                 g_part_gpt_efimedia(entry, sb);
 793                 sbuf_cat(sb, "</efimedia>\n");
 794         } else {
 795                 /* confxml: scheme information */
 796         }
 797 }
 798
 799 static int
 800 g_part_gpt_dumpto(struct g_part_table *table, struct g_part_entry *baseentry)
 801 {
 802         struct g_part_gpt_entry *entry;
 803
 804         entry = (struct g_part_gpt_entry *)baseentry;
 805         return ((EQUUID(&entry->ent.ent_type, &gpt_uuid_freebsd_swap) ||
 806             EQUUID(&entry->ent.ent_type, &gpt_uuid_linux_swap) ||
 807             EQUUID(&entry->ent.ent_type, &gpt_uuid_dfbsd_swap)) ? 1 : 0);
 808 }
 809
 810 static int
 811 g_part_gpt_modify(struct g_part_table *basetable,
 812     struct g_part_entry *baseentry, struct g_part_parms *gpp)
 813 {
 814         struct g_part_gpt_entry *entry;
 815         int error;
 816
 817         entry = (struct g_part_gpt_entry *)baseentry;
 818         if (gpp->gpp_parms & G_PART_PARM_TYPE) {
 819                 error = gpt_parse_type(gpp->gpp_type, &entry->ent.ent_type);
 820                 if (error)
 821                         return (error);
 822         }
 823         if (gpp->gpp_parms & G_PART_PARM_LABEL)
 824                 g_gpt_utf8_to_utf16(gpp->gpp_label, entry->ent.ent_name,
 825                     sizeof(entry->ent.ent_name) /
 826                     sizeof(entry->ent.ent_name[0]));
 827         return (0);
 828 }
 829
 830 static int
 831 g_part_gpt_resize(struct g_part_table *basetable,
 832     struct g_part_entry *baseentry, struct g_part_parms *gpp)
 833 {
 834         struct g_part_gpt_entry *entry;
 835
 836         if (baseentry == NULL)
 837                 return (g_part_gpt_recover(basetable));
 838
 839         entry = (struct g_part_gpt_entry *)baseentry;
 840         baseentry->gpe_end = baseentry->gpe_start + gpp->gpp_size - 1;
 841         entry->ent.ent_lba_end = baseentry->gpe_end;
 842
 843         return (0);
 844 }
 845
 846 static const char *
 847 g_part_gpt_name(struct g_part_table *table, struct g_part_entry *baseentry,
 848     char *buf, size_t bufsz)
 849 {
 850         struct g_part_gpt_entry *entry;
 851         char c;
 852
 853         entry = (struct g_part_gpt_entry *)baseentry;
 854         c = (EQUUID(&entry->ent.ent_type, &gpt_uuid_freebsd)) ? 's' : 'p';
 855         snprintf(buf, bufsz, "%c%d", c, baseentry->gpe_index);
 856         return (buf);
 857 }
 858
 859 static int
 860 g_part_gpt_probe(struct g_part_table *table, struct g_consumer *cp)
 861 {
 862         struct g_provider *pp;
 863         u_char *buf;
 864         int error, index, pri, res;
 865
 866         /* Our depth should be 0 unless nesting was explicitly enabled. */
 867         if (!allow_nesting && table->gpt_depth != 0)
 868                 return (ENXIO);
 869
 870         pp = cp->provider;
 871
 872         /*
 873          * Sanity-check the provider. Since the first sector on the provider
 874          * must be a PMBR and a PMBR is 512 bytes large, the sector size
 875          * must be at least 512 bytes.  Also, since the theoretical minimum
 876          * number of sectors needed by GPT is 6, any medium that has less
 877          * than 6 sectors is never going to be able to hold a GPT. The
 878          * number 6 comes from:
 879          *      1 sector for the PMBR
 880          *      2 sectors for the GPT headers (each 1 sector)
 881          *      2 sectors for the GPT tables (each 1 sector)
 882          *      1 sector for an actual partition
 883          * It's better to catch this pathological case early than behaving
 884          * pathologically later on...
 885          */
 886         if (pp->sectorsize < MBRSIZE || pp->mediasize < 6 * pp->sectorsize)
 887                 return (ENOSPC);
 888
 889         /*
 890          * Check that there's a MBR or a PMBR. If it's a PMBR, we return
 891          * as the highest priority on a match, otherwise we assume some
 892          * GPT-unaware tool has destroyed the GPT by recreating a MBR and
 893          * we really want the MBR scheme to take precedence.
 894          */
 895         buf = g_read_data(cp, 0L, pp->sectorsize, &error);
 896         if (buf == NULL)
 897                 return (error);
 898         res = le16dec(buf + DOSMAGICOFFSET);
 899         pri = G_PART_PROBE_PRI_LOW;
 900         if (res == DOSMAGIC) {
 901                 for (index = 0; index < NDOSPART; index++) {
 902                         if (buf[DOSPARTOFF + DOSPARTSIZE * index + 4] == 0xee)
 903                                 pri = G_PART_PROBE_PRI_HIGH;
 904                 }
 905                 g_free(buf);
 906
 907                 /* Check that there's a primary header. */
 908                 buf = g_read_data(cp, pp->sectorsize, pp->sectorsize, &error);
 909                 if (buf == NULL)
 910                         return (error);
 911                 res = memcmp(buf, GPT_HDR_SIG, 8);
 912                 g_free(buf);
 913                 if (res == 0)
 914                         return (pri);
 915         } else
 916                 g_free(buf);
 917
 918         /* No primary? Check that there's a secondary. */
 919         buf = g_read_data(cp, pp->mediasize - pp->sectorsize, pp->sectorsize,
 920             &error);
 921         if (buf == NULL)
 922                 return (error);
 923         res = memcmp(buf, GPT_HDR_SIG, 8);
 924         g_free(buf);
 925         return ((res == 0) ? pri : ENXIO);
 926 }
 927
 928 static int
 929 g_part_gpt_read(struct g_part_table *basetable, struct g_consumer *cp)
 930 {
 931         struct gpt_hdr *prihdr, *sechdr;
 932         struct gpt_ent *tbl, *pritbl, *sectbl;
 933         struct g_provider *pp;
 934         struct g_part_gpt_table *table;
 935         struct g_part_gpt_entry *entry;
 936         u_char *buf;
 937         uint64_t last;
 938         int error, index;
 939
 940         table = (struct g_part_gpt_table *)basetable;
 941         pp = cp->provider;
 942         last = (pp->mediasize / pp->sectorsize) - 1;
 943
 944         /* Read the PMBR */
 945         buf = g_read_data(cp, 0, pp->sectorsize, &error);
 946         if (buf == NULL)
 947                 return (error);
 948         bcopy(buf, table->mbr, MBRSIZE);
 949         g_free(buf);
 950
 951         /* Read the primary header and table. */
 952         prihdr = gpt_read_hdr(table, cp, GPT_ELT_PRIHDR);
 953         if (table->state[GPT_ELT_PRIHDR] == GPT_STATE_OK) {
 954                 pritbl = gpt_read_tbl(table, cp, GPT_ELT_PRITBL, prihdr);
 955         } else {
 956                 table->state[GPT_ELT_PRITBL] = GPT_STATE_MISSING;
 957                 pritbl = NULL;
 958         }
 959
 960         /* Read the secondary header and table. */
 961         sechdr = gpt_read_hdr(table, cp, GPT_ELT_SECHDR);
 962         if (table->state[GPT_ELT_SECHDR] == GPT_STATE_OK) {
 963                 sectbl = gpt_read_tbl(table, cp, GPT_ELT_SECTBL, sechdr);
 964         } else {
 965                 table->state[GPT_ELT_SECTBL] = GPT_STATE_MISSING;
 966                 sectbl = NULL;
 967         }
 968
 969         /* Fail if we haven't got any good tables at all. */
 970         if (table->state[GPT_ELT_PRITBL] != GPT_STATE_OK &&
 971             table->state[GPT_ELT_SECTBL] != GPT_STATE_OK) {
 972                 if (table->state[GPT_ELT_PRITBL] == GPT_STATE_UNSUPPORTED &&
 973                     table->state[GPT_ELT_SECTBL] == GPT_STATE_UNSUPPORTED &&
 974                     gpt_matched_hdrs(prihdr, sechdr)) {
 975                         printf("GEOM: %s: unsupported GPT detected.\n",
 976                             pp->name);
 977                         printf(
 978                     "GEOM: %s: number of GPT entries: %u, entry size: %uB.\n",
 979                             pp->name, prihdr->hdr_entries, prihdr->hdr_entsz);
 980                         printf(
 981     "GEOM: %s: maximum supported number of GPT entries: %u, entry size: %uB.\n",
 982                             pp->name, g_part_gpt_scheme.gps_maxent, MAXENTSIZE);
 983                         printf("GEOM: %s: GPT rejected.\n", pp->name);
 984                 } else {
 985                         printf("GEOM: %s: corrupt or invalid GPT detected.\n",
 986                             pp->name);
 987                         printf(
 988                     "GEOM: %s: GPT rejected -- may not be recoverable.\n",
 989                             pp->name);
 990                 }
 991                 g_free(prihdr);
 992                 g_free(pritbl);
 993                 g_free(sechdr);
 994                 g_free(sectbl);
 995                 return (EINVAL);
 996         }
 997
 998         /*
 999          * If both headers are good but they disagree with each other,
1000          * then invalidate one. We prefer to keep the primary header,
1001          * unless the primary table is corrupt.
1002          */
1003         if (table->state[GPT_ELT_PRIHDR] == GPT_STATE_OK &&
1004             table->state[GPT_ELT_SECHDR] == GPT_STATE_OK &&
1005             !gpt_matched_hdrs(prihdr, sechdr)) {
1006                 if (table->state[GPT_ELT_PRITBL] == GPT_STATE_OK) {
1007                         table->state[GPT_ELT_SECHDR] = GPT_STATE_INVALID;
1008                         table->state[GPT_ELT_SECTBL] = GPT_STATE_MISSING;
1009                         g_free(sechdr);
1010                         sechdr = NULL;
1011                 } else {
1012                         table->state[GPT_ELT_PRIHDR] = GPT_STATE_INVALID;
1013                         table->state[GPT_ELT_PRITBL] = GPT_STATE_MISSING;
1014                         g_free(prihdr);
1015                         prihdr = NULL;
1016                 }
1017         }
1018
1019         if (table->state[GPT_ELT_PRITBL] != GPT_STATE_OK) {
1020                 printf("GEOM: %s: the primary GPT table is corrupt or "
1021                     "invalid.\n", pp->name);
1022                 printf("GEOM: %s: using the secondary instead -- recovery "
1023                     "strongly advised.\n", pp->name);
1024                 table->hdr = sechdr;
1025                 basetable->gpt_corrupt = 1;
1026                 g_free(prihdr);
1027                 tbl = sectbl;
1028                 g_free(pritbl);
1029         } else {
1030                 if (table->state[GPT_ELT_SECTBL] != GPT_STATE_OK) {
1031                         printf("GEOM: %s: the secondary GPT table is corrupt "
1032                             "or invalid.\n", pp->name);
1033                         printf("GEOM: %s: using the primary only -- recovery "
1034                             "suggested.\n", pp->name);
1035                         basetable->gpt_corrupt = 1;
1036                 } else if (table->lba[GPT_ELT_SECHDR] != last) {
1037                         printf( "GEOM: %s: the secondary GPT header is not in "
1038                             "the last LBA.\n", pp->name);
1039                         basetable->gpt_corrupt = 1;
1040                 }
1041                 table->hdr = prihdr;
1042                 g_free(sechdr);
1043                 tbl = pritbl;
1044                 g_free(sectbl);
1045         }
1046
1047         basetable->gpt_first = table->hdr->hdr_lba_start;
1048         basetable->gpt_last = table->hdr->hdr_lba_end;
1049         basetable->gpt_entries = table->hdr->hdr_entries;
1050
1051         for (index = basetable->gpt_entries - 1; index >= 0; index--) {
1052                 if (EQUUID(&tbl[index].ent_type, &gpt_uuid_unused))
1053                         continue;
1054                 entry = (struct g_part_gpt_entry *)g_part_new_entry(
1055                     basetable, index + 1, tbl[index].ent_lba_start,
1056                     tbl[index].ent_lba_end);
1057                 entry->ent = tbl[index];
1058         }
1059
1060         g_free(tbl);
1061
1062         /*
1063          * Under Mac OS X, the MBR mirrors the first 4 GPT partitions
1064          * if (and only if) any FAT32 or FAT16 partitions have been
1065          * created. This happens irrespective of whether Boot Camp is
1066          * used/enabled, though it's generally understood to be done
1067          * to support legacy Windows under Boot Camp. We refer to this
1068          * mirroring simply as Boot Camp. We try to detect Boot Camp
1069          * so that we can update the MBR if and when GPT changes have
1070          * been made. Note that we do not enable Boot Camp if not
1071          * previously enabled because we can't assume that we're on a
1072          * Mac alongside Mac OS X.
1073          */
1074         table->bootcamp = gpt_is_bootcamp(table, pp->name);
1075
1076         return (0);
1077 }
1078
1079 static int
1080 g_part_gpt_recover(struct g_part_table *basetable)
1081 {
1082         struct g_part_gpt_table *table;
1083         struct g_provider *pp;
1084
1085         table = (struct g_part_gpt_table *)basetable;
1086         pp = LIST_FIRST(&basetable->gpt_gp->consumer)->provider;
1087         gpt_create_pmbr(table, pp);
1088         g_gpt_set_defaults(basetable, pp);
1089         basetable->gpt_corrupt = 0;
1090         return (0);
1091 }
1092
1093 static int
1094 g_part_gpt_setunset(struct g_part_table *basetable,
1095     struct g_part_entry *baseentry, const char *attrib, unsigned int set)
1096 {
1097         struct g_part_gpt_entry *entry;
1098         struct g_part_gpt_table *table;
1099         struct g_provider *pp;
1100         uint8_t *p;
1101         uint64_t attr;
1102         int i;
1103
1104         table = (struct g_part_gpt_table *)basetable;
1105         entry = (struct g_part_gpt_entry *)baseentry;
1106
1107         if (strcasecmp(attrib, "active") == 0) {
1108                 if (table->bootcamp) {
1109                         /* The active flag must be set on a valid entry. */
1110                         if (entry == NULL)
1111                                 return (ENXIO);
1112                         if (baseentry->gpe_index > NDOSPART)
1113                                 return (EINVAL);
1114                         for (i = 0; i < NDOSPART; i++) {
1115                                 p = &table->mbr[DOSPARTOFF + i * DOSPARTSIZE];
1116                                 p[0] = (i == baseentry->gpe_index - 1)
1117                                     ? ((set) ? 0x80 : 0) : 0;
1118                         }
1119                 } else {
1120                         /* The PMBR is marked as active without an entry. */
1121                         if (entry != NULL)
1122                                 return (ENXIO);
1123                         for (i = 0; i < NDOSPART; i++) {
1124                                 p = &table->mbr[DOSPARTOFF + i * DOSPARTSIZE];
1125                                 p[0] = (p[4] == 0xee) ? ((set) ? 0x80 : 0) : 0;
1126                         }
1127                 }
1128                 return (0);
1129         } else if (strcasecmp(attrib, "lenovofix") == 0) {
1130                 /*
1131                  * Write the 0xee GPT entry to slot #1 (2nd slot) in the pMBR.
1132                  * This workaround allows Lenovo X220, T420, T520, etc to boot
1133                  * from GPT Partitions in BIOS mode.
1134                  */
1135
1136                 if (entry != NULL)
1137                         return (ENXIO);
1138
1139                 pp = LIST_FIRST(&basetable->gpt_gp->consumer)->provider;
1140                 bzero(table->mbr + DOSPARTOFF, DOSPARTSIZE * NDOSPART);
1141                 gpt_write_mbr_entry(table->mbr, ((set) ? 1 : 0), 0xee, 1,
1142                     MIN(pp->mediasize / pp->sectorsize - 1, UINT32_MAX));
1143                 return (0);
1144         }
1145
1146         if (entry == NULL)
1147                 return (ENODEV);
1148
1149         attr = 0;
1150         if (strcasecmp(attrib, "bootme") == 0) {
1151                 attr |= GPT_ENT_ATTR_BOOTME;
1152         } else if (strcasecmp(attrib, "bootonce") == 0) {
1153                 attr |= GPT_ENT_ATTR_BOOTONCE;
1154                 if (set)
1155                         attr |= GPT_ENT_ATTR_BOOTME;
1156         } else if (strcasecmp(attrib, "bootfailed") == 0) {
1157                 /*
1158                  * It should only be possible to unset BOOTFAILED, but it might
1159                  * be useful for test purposes to also be able to set it.
1160                  */
1161                 attr |= GPT_ENT_ATTR_BOOTFAILED;
1162         }
1163         if (attr == 0)
1164                 return (EINVAL);
1165
1166         if (set)
1167                 attr = entry->ent.ent_attr | attr;
1168         else
1169                 attr = entry->ent.ent_attr & ~attr;
1170         if (attr != entry->ent.ent_attr) {
1171                 entry->ent.ent_attr = attr;
1172                 if (!baseentry->gpe_created)
1173                         baseentry->gpe_modified = 1;
1174         }
1175         return (0);
1176 }
1177
1178 static const char *
1179 g_part_gpt_type(struct g_part_table *basetable, struct g_part_entry *baseentry,
1180     char *buf, size_t bufsz)
1181 {
1182         struct g_part_gpt_entry *entry;
1183         struct uuid *type;
1184         struct g_part_uuid_alias *uap;
1185
1186         entry = (struct g_part_gpt_entry *)baseentry;
1187         type = &entry->ent.ent_type;
1188         for (uap = &gpt_uuid_alias_match[0]; uap->uuid; uap++)
1189                 if (EQUUID(type, uap->uuid))
1190                         return (g_part_alias_name(uap->alias));
1191         buf[0] = '!';
1192         snprintf_uuid(buf + 1, bufsz - 1, type);
1193
1194         return (buf);
1195 }
1196
1197 static int
1198 g_part_gpt_write(struct g_part_table *basetable, struct g_consumer *cp)
1199 {
1200         unsigned char *buf, *bp;
1201         struct g_provider *pp;
1202         struct g_part_entry *baseentry;
1203         struct g_part_gpt_entry *entry;
1204         struct g_part_gpt_table *table;
1205         size_t tblsz;
1206         uint32_t crc;
1207         int error, index;
1208
1209         pp = cp->provider;
1210         table = (struct g_part_gpt_table *)basetable;
1211         tblsz = howmany(table->hdr->hdr_entries * table->hdr->hdr_entsz,
1212             pp->sectorsize);
1213
1214         /* Reconstruct the MBR from the GPT if under Boot Camp. */
1215         if (table->bootcamp)
1216                 gpt_update_bootcamp(basetable, pp);
1217
1218         /* Write the PMBR */
1219         buf = g_malloc(pp->sectorsize, M_WAITOK | M_ZERO);
1220         bcopy(table->mbr, buf, MBRSIZE);
1221         error = g_write_data(cp, 0, buf, pp->sectorsize);
1222         g_free(buf);
1223         if (error)
1224                 return (error);
1225
1226         /* Allocate space for the header and entries. */
1227         buf = g_malloc((tblsz + 1) * pp->sectorsize, M_WAITOK | M_ZERO);
1228
1229         memcpy(buf, table->hdr->hdr_sig, sizeof(table->hdr->hdr_sig));
1230         le32enc(buf + 8, table->hdr->hdr_revision);
1231         le32enc(buf + 12, table->hdr->hdr_size);
1232         le64enc(buf + 40, table->hdr->hdr_lba_start);
1233         le64enc(buf + 48, table->hdr->hdr_lba_end);
1234         le_uuid_enc(buf + 56, &table->hdr->hdr_uuid);
1235         le32enc(buf + 80, table->hdr->hdr_entries);
1236         le32enc(buf + 84, table->hdr->hdr_entsz);
1237
1238         LIST_FOREACH(baseentry, &basetable->gpt_entry, gpe_entry) {
1239                 if (baseentry->gpe_deleted)
1240                         continue;
1241                 entry = (struct g_part_gpt_entry *)baseentry;
1242                 index = baseentry->gpe_index - 1;
1243                 bp = buf + pp->sectorsize + table->hdr->hdr_entsz * index;
1244                 le_uuid_enc(bp, &entry->ent.ent_type);
1245                 le_uuid_enc(bp + 16, &entry->ent.ent_uuid);
1246                 le64enc(bp + 32, entry->ent.ent_lba_start);
1247                 le64enc(bp + 40, entry->ent.ent_lba_end);
1248                 le64enc(bp + 48, entry->ent.ent_attr);
1249                 memcpy(bp + 56, entry->ent.ent_name,
1250                     sizeof(entry->ent.ent_name));
1251         }
1252
1253         crc = crc32(buf + pp->sectorsize,
1254             table->hdr->hdr_entries * table->hdr->hdr_entsz);
1255         le32enc(buf + 88, crc);
1256
1257         /* Write primary meta-data. */
1258         le32enc(buf + 16, 0);   /* hdr_crc_self. */
1259         le64enc(buf + 24, table->lba[GPT_ELT_PRIHDR]);  /* hdr_lba_self. */
1260         le64enc(buf + 32, table->lba[GPT_ELT_SECHDR]);  /* hdr_lba_alt. */
1261         le64enc(buf + 72, table->lba[GPT_ELT_PRITBL]);  /* hdr_lba_table. */
1262         crc = crc32(buf, table->hdr->hdr_size);
1263         le32enc(buf + 16, crc);
1264
1265         for (index = 0; index < tblsz; index += maxphys / pp->sectorsize) {
1266                 error = g_write_data(cp,
1267                     (table->lba[GPT_ELT_PRITBL] + index) * pp->sectorsize,
1268                     buf + (index + 1) * pp->sectorsize,
1269                     (tblsz - index > maxphys / pp->sectorsize) ? maxphys :
1270                     (tblsz - index) * pp->sectorsize);
1271                 if (error)
1272                         goto out;
1273         }
1274         error = g_write_data(cp, table->lba[GPT_ELT_PRIHDR] * pp->sectorsize,
1275             buf, pp->sectorsize);
1276         if (error)
1277                 goto out;
1278
1279         /* Write secondary meta-data. */
1280         le32enc(buf + 16, 0);   /* hdr_crc_self. */
1281         le64enc(buf + 24, table->lba[GPT_ELT_SECHDR]);  /* hdr_lba_self. */
1282         le64enc(buf + 32, table->lba[GPT_ELT_PRIHDR]);  /* hdr_lba_alt. */
1283         le64enc(buf + 72, table->lba[GPT_ELT_SECTBL]);  /* hdr_lba_table. */
1284         crc = crc32(buf, table->hdr->hdr_size);
1285         le32enc(buf + 16, crc);
1286
1287         for (index = 0; index < tblsz; index += maxphys / pp->sectorsize) {
1288                 error = g_write_data(cp,
1289                     (table->lba[GPT_ELT_SECTBL] + index) * pp->sectorsize,
1290                     buf + (index + 1) * pp->sectorsize,
1291                     (tblsz - index > maxphys / pp->sectorsize) ? maxphys :
1292                     (tblsz - index) * pp->sectorsize);
1293                 if (error)
1294                         goto out;
1295         }
1296         error = g_write_data(cp, table->lba[GPT_ELT_SECHDR] * pp->sectorsize,
1297             buf, pp->sectorsize);
1298
1299  out:
1300         g_free(buf);
1301         return (error);
1302 }
1303
1304 static void
1305 g_gpt_set_defaults(struct g_part_table *basetable, struct g_provider *pp)
1306 {
1307         struct g_part_entry *baseentry;
1308         struct g_part_gpt_entry *entry;
1309         struct g_part_gpt_table *table;
1310         quad_t start, end, min, max;
1311         quad_t lba, last;
1312         size_t spb, tblsz;
1313
1314         table = (struct g_part_gpt_table *)basetable;
1315         last = pp->mediasize / pp->sectorsize - 1;
1316         tblsz = howmany(basetable->gpt_entries * sizeof(struct gpt_ent),
1317             pp->sectorsize);
1318
1319         table->lba[GPT_ELT_PRIHDR] = 1;
1320         table->lba[GPT_ELT_PRITBL] = 2;
1321         table->lba[GPT_ELT_SECHDR] = last;
1322         table->lba[GPT_ELT_SECTBL] = last - tblsz;
1323         table->state[GPT_ELT_PRIHDR] = GPT_STATE_OK;
1324         table->state[GPT_ELT_PRITBL] = GPT_STATE_OK;
1325         table->state[GPT_ELT_SECHDR] = GPT_STATE_OK;
1326         table->state[GPT_ELT_SECTBL] = GPT_STATE_OK;
1327
1328         max = start = 2 + tblsz;
1329         min = end = last - tblsz - 1;
1330         LIST_FOREACH(baseentry, &basetable->gpt_entry, gpe_entry) {
1331                 if (baseentry->gpe_deleted)
1332                         continue;
1333                 entry = (struct g_part_gpt_entry *)baseentry;
1334                 if (entry->ent.ent_lba_start < min)
1335                         min = entry->ent.ent_lba_start;
1336                 if (entry->ent.ent_lba_end > max)
1337                         max = entry->ent.ent_lba_end;
1338         }
1339         spb = 4096 / pp->sectorsize;
1340         if (spb > 1) {
1341                 lba = start + ((start % spb) ? spb - start % spb : 0);
1342                 if (lba <= min)
1343                         start = lba;
1344                 lba = end - (end + 1) % spb;
1345                 if (max <= lba)
1346                         end = lba;
1347         }
1348         table->hdr->hdr_lba_start = start;
1349         table->hdr->hdr_lba_end = end;
1350
1351         basetable->gpt_first = start;
1352         basetable->gpt_last = end;
1353 }
1354
1355 static void
1356 g_gpt_printf_utf16(struct sbuf *sb, uint16_t *str, size_t len)
1357 {
1358         u_int bo;
1359         uint32_t ch;
1360         uint16_t c;
1361
1362         bo = LITTLE_ENDIAN;     /* GPT is little-endian */
1363         while (len > 0 && *str != 0) {
1364                 ch = (bo == BIG_ENDIAN) ? be16toh(*str) : le16toh(*str);
1365                 str++, len--;
1366                 if ((ch & 0xf800) == 0xd800) {
1367                         if (len > 0) {
1368                                 c = (bo == BIG_ENDIAN) ? be16toh(*str)
1369                                     : le16toh(*str);
1370                                 str++, len--;
1371                         } else
1372                                 c = 0xfffd;
1373                         if ((ch & 0x400) == 0 && (c & 0xfc00) == 0xdc00) {
1374                                 ch = ((ch & 0x3ff) << 10) + (c & 0x3ff);
1375                                 ch += 0x10000;
1376                         } else
1377                                 ch = 0xfffd;
1378                 } else if (ch == 0xfffe) { /* BOM (U+FEFF) swapped. */
1379                         bo = (bo == BIG_ENDIAN) ? LITTLE_ENDIAN : BIG_ENDIAN;
1380                         continue;
1381                 } else if (ch == 0xfeff) /* BOM (U+FEFF) unswapped. */
1382                         continue;
1383
1384                 /* Write the Unicode character in UTF-8 */
1385                 if (ch < 0x80)
1386                         g_conf_printf_escaped(sb, "%c", ch);
1387                 else if (ch < 0x800)
1388                         g_conf_printf_escaped(sb, "%c%c", 0xc0 | (ch >> 6),
1389                             0x80 | (ch & 0x3f));
1390                 else if (ch < 0x10000)
1391                         g_conf_printf_escaped(sb, "%c%c%c", 0xe0 | (ch >> 12),
1392                             0x80 | ((ch >> 6) & 0x3f), 0x80 | (ch & 0x3f));
1393                 else if (ch < 0x200000)
1394                         g_conf_printf_escaped(sb, "%c%c%c%c", 0xf0 |
1395                             (ch >> 18), 0x80 | ((ch >> 12) & 0x3f),
1396                             0x80 | ((ch >> 6) & 0x3f), 0x80 | (ch & 0x3f));
1397         }
1398 }
1399
1400 static void
1401 g_gpt_utf8_to_utf16(const uint8_t *s8, uint16_t *s16, size_t s16len)
1402 {
1403         size_t s16idx, s8idx;
1404         uint32_t utfchar;
1405         unsigned int c, utfbytes;
1406
1407         s8idx = s16idx = 0;
1408         utfchar = 0;
1409         utfbytes = 0;
1410         bzero(s16, s16len << 1);
1411         while (s8[s8idx] != 0 && s16idx < s16len) {
1412                 c = s8[s8idx++];
1413                 if ((c & 0xc0) != 0x80) {
1414                         /* Initial characters. */
1415                         if (utfbytes != 0) {
1416                                 /* Incomplete encoding of previous char. */
1417                                 s16[s16idx++] = htole16(0xfffd);
1418                         }
1419                         if ((c & 0xf8) == 0xf0) {
1420                                 utfchar = c & 0x07;
1421                                 utfbytes = 3;
1422                         } else if ((c & 0xf0) == 0xe0) {
1423                                 utfchar = c & 0x0f;
1424                                 utfbytes = 2;
1425                         } else if ((c & 0xe0) == 0xc0) {
1426                                 utfchar = c & 0x1f;
1427                                 utfbytes = 1;
1428                         } else {
1429                                 utfchar = c & 0x7f;
1430                                 utfbytes = 0;
1431                         }
1432                 } else {
1433                         /* Followup characters. */
1434                         if (utfbytes > 0) {
1435                                 utfchar = (utfchar << 6) + (c & 0x3f);
1436                                 utfbytes--;
1437                         } else if (utfbytes == 0)
1438                                 utfbytes = ~0;
1439                 }
1440                 /*
1441                  * Write the complete Unicode character as UTF-16 when we
1442                  * have all the UTF-8 charactars collected.
1443                  */
1444                 if (utfbytes == 0) {
1445                         /*
1446                          * If we need to write 2 UTF-16 characters, but
1447                          * we only have room for 1, then we truncate the
1448                          * string by writing a 0 instead.
1449                          */
1450                         if (utfchar >= 0x10000 && s16idx < s16len - 1) {
1451                                 s16[s16idx++] =
1452                                     htole16(0xd800 | ((utfchar >> 10) - 0x40));
1453                                 s16[s16idx++] =
1454                                     htole16(0xdc00 | (utfchar & 0x3ff));
1455                         } else
1456                                 s16[s16idx++] = (utfchar >= 0x10000) ? 0 :
1457                                     htole16(utfchar);
1458                 }
1459         }
1460         /*
1461          * If our input string was truncated, append an invalid encoding
1462          * character to the output string.
1463          */
1464         if (utfbytes != 0 && s16idx < s16len)
1465                 s16[s16idx++] = htole16(0xfffd);
1466 }