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