From 3b2674aef78723fb683591d04ba3e949a5f99905 Mon Sep 17 00:00:00 2001 From: Michael Marineau Date: Sat, 18 Oct 2014 15:39:13 -0700 Subject: [PATCH 1/5] gpt: rename misnamed header location fields The header location fields refer to 'this header' and 'alternate header' respectively, not 'primary header' and 'backup header'. The previous field names are backwards for the backup header. --- grub-core/lib/gpt.c | 2 +- include/grub/gpt_partition.h | 4 ++-- tests/gpt_unit_test.c | 8 ++++---- 3 files changed, 7 insertions(+), 7 deletions(-) diff --git a/grub-core/lib/gpt.c b/grub-core/lib/gpt.c index a308e8537..705bd77f9 100644 --- a/grub-core/lib/gpt.c +++ b/grub-core/lib/gpt.c @@ -137,7 +137,7 @@ grub_gpt_read_backup (grub_disk_t disk, grub_gpt_t gpt) if (disk->total_sectors != GRUB_DISK_SIZE_UNKNOWN) sector = disk->total_sectors - 1; else if (gpt->status & GRUB_GPT_PRIMARY_HEADER_VALID) - sector = grub_le_to_cpu64 (gpt->primary.backup); + sector = grub_le_to_cpu64 (gpt->primary.alternate_lba); else return grub_error (GRUB_ERR_NOT_IMPLEMENTED_YET, "Unable to locate backup GPT"); diff --git a/include/grub/gpt_partition.h b/include/grub/gpt_partition.h index 04ed2d7f1..a7ef61875 100644 --- a/include/grub/gpt_partition.h +++ b/include/grub/gpt_partition.h @@ -64,8 +64,8 @@ struct grub_gpt_header grub_uint32_t headersize; grub_uint32_t crc32; grub_uint32_t unused1; - grub_uint64_t primary; - grub_uint64_t backup; + grub_uint64_t header_lba; + grub_uint64_t alternate_lba; grub_uint64_t start; grub_uint64_t end; grub_uint8_t guid[16]; diff --git a/tests/gpt_unit_test.c b/tests/gpt_unit_test.c index a824cd967..4d70868af 100644 --- a/tests/gpt_unit_test.c +++ b/tests/gpt_unit_test.c @@ -94,8 +94,8 @@ static const struct grub_gpt_header example_primary = { .version = GRUB_GPT_HEADER_VERSION, .headersize = sizeof (struct grub_gpt_header), .crc32 = grub_cpu_to_le32_compile_time (0x7cd8642c), - .primary = grub_cpu_to_le64_compile_time (PRIMARY_HEADER_SECTOR), - .backup = grub_cpu_to_le64_compile_time (BACKUP_HEADER_SECTOR), + .header_lba = grub_cpu_to_le64_compile_time (PRIMARY_HEADER_SECTOR), + .alternate_lba = grub_cpu_to_le64_compile_time (BACKUP_HEADER_SECTOR), .start = grub_cpu_to_le64_compile_time (DATA_START_SECTOR), .end = grub_cpu_to_le64_compile_time (DATA_END_SECTOR), .guid = {0xad, 0x31, 0xc1, 0x69, 0xd6, 0x67, 0xc6, 0x46, @@ -112,8 +112,8 @@ static const struct grub_gpt_header example_backup = { .version = GRUB_GPT_HEADER_VERSION, .headersize = sizeof (struct grub_gpt_header), .crc32 = grub_cpu_to_le32_compile_time (0xcfaa4a27), - .primary = grub_cpu_to_le64_compile_time (BACKUP_HEADER_SECTOR), - .backup = grub_cpu_to_le64_compile_time (PRIMARY_HEADER_SECTOR), + .header_lba = grub_cpu_to_le64_compile_time (BACKUP_HEADER_SECTOR), + .alternate_lba = grub_cpu_to_le64_compile_time (PRIMARY_HEADER_SECTOR), .start = grub_cpu_to_le64_compile_time (DATA_START_SECTOR), .end = grub_cpu_to_le64_compile_time (DATA_END_SECTOR), .guid = {0xad, 0x31, 0xc1, 0x69, 0xd6, 0x67, 0xc6, 0x46, From 4dd009a6fbb3a7d98fe37ffe7f22e0f35768886d Mon Sep 17 00:00:00 2001 From: Michael Marineau Date: Sat, 18 Oct 2014 16:46:17 -0700 Subject: [PATCH 2/5] gpt: record size of of the entries table The size of the entries table will be needed later when writing it back to disk. Restructure the entries reading code to flow a little better. --- grub-core/lib/gpt.c | 53 ++++++++++++++++-------------------- include/grub/gpt_partition.h | 5 +++- 2 files changed, 27 insertions(+), 31 deletions(-) diff --git a/grub-core/lib/gpt.c b/grub-core/lib/gpt.c index 705bd77f9..01df7f3e8 100644 --- a/grub-core/lib/gpt.c +++ b/grub-core/lib/gpt.c @@ -153,7 +153,7 @@ grub_gpt_read_backup (grub_disk_t disk, grub_gpt_t gpt) return GRUB_ERR_NONE; } -static struct grub_gpt_partentry * +static grub_err_t grub_gpt_read_entries (grub_disk_t disk, grub_gpt_t gpt, struct grub_gpt_header *header) { @@ -173,6 +173,10 @@ grub_gpt_read_entries (grub_disk_t disk, grub_gpt_t gpt, goto fail; } + /* Double check that the header was validated properly. */ + if (entries_size < GRUB_GPT_DEFAULT_ENTRIES_SIZE) + return grub_error (GRUB_ERR_BUG, "invalid GPT entries table size"); + entries = grub_malloc (entries_size); if (!entries) goto fail; @@ -197,19 +201,21 @@ grub_gpt_read_entries (grub_disk_t disk, grub_gpt_t gpt, } grub_free (crc32_context); - return entries; + grub_free (gpt->entries); + gpt->entries = entries; + gpt->entries_size = entries_size; + return GRUB_ERR_NONE; fail: grub_free (entries); grub_free (crc32_context); - return NULL; + return grub_errno; } grub_gpt_t grub_gpt_read (grub_disk_t disk) { grub_gpt_t gpt; - struct grub_gpt_partentry *backup_entries; gpt = grub_zalloc (sizeof (*gpt)); if (!gpt) @@ -241,36 +247,23 @@ grub_gpt_read (grub_disk_t disk) else goto fail; - /* Same error handling scheme for the entry tables. */ - gpt->entries = grub_gpt_read_entries (disk, gpt, &gpt->primary); - if (!gpt->entries) - { - grub_error_push (); - backup_entries = grub_gpt_read_entries (disk, gpt, &gpt->backup); - grub_error_pop (); - } - else - { - gpt->status |= GRUB_GPT_PRIMARY_ENTRIES_VALID; - backup_entries = grub_gpt_read_entries (disk, gpt, &gpt->backup); - } + /* Similarly, favor the value or error from the primary table. */ + if (gpt->status & GRUB_GPT_BACKUP_HEADER_VALID && + !grub_gpt_read_entries (disk, gpt, &gpt->backup)) + gpt->status |= GRUB_GPT_BACKUP_ENTRIES_VALID; - if (backup_entries) - { - gpt->status |= GRUB_GPT_BACKUP_ENTRIES_VALID; - - if (gpt->status & GRUB_GPT_PRIMARY_ENTRIES_VALID) - grub_free (backup_entries); - else - gpt->entries = backup_entries; - } + grub_errno = GRUB_ERR_NONE; + if (gpt->status & GRUB_GPT_PRIMARY_HEADER_VALID && + !grub_gpt_read_entries (disk, gpt, &gpt->primary)) + gpt->status |= GRUB_GPT_PRIMARY_ENTRIES_VALID; if (gpt->status & GRUB_GPT_PRIMARY_ENTRIES_VALID || gpt->status & GRUB_GPT_BACKUP_ENTRIES_VALID) - { - grub_errno = GRUB_ERR_NONE; - return gpt; - } + grub_errno = GRUB_ERR_NONE; + else + goto fail; + + return gpt; fail: grub_gpt_free (gpt); diff --git a/include/grub/gpt_partition.h b/include/grub/gpt_partition.h index a7ef61875..7f41e22dd 100644 --- a/include/grub/gpt_partition.h +++ b/include/grub/gpt_partition.h @@ -106,7 +106,9 @@ typedef enum grub_gpt_status /* UEFI requires the entries table to be at least 16384 bytes for a * total of 128 entries given the standard 128 byte entry size. */ -#define GRUB_GPT_DEFAULT_ENTRIES_LENGTH 128 +#define GRUB_GPT_DEFAULT_ENTRIES_SIZE 16384 +#define GRUB_GPT_DEFAULT_ENTRIES_LENGTH \ + (GRUB_GPT_DEFAULT_ENTRIES_SIZE / sizeof (struct grub_gpt_partentry)) struct grub_gpt { @@ -122,6 +124,7 @@ struct grub_gpt /* Only need one entries table, on disk both copies are identical. */ struct grub_gpt_partentry *entries; + grub_size_t entries_size; /* Logarithm of sector size, in case GPT and disk driver disagree. */ unsigned int log_sector_size; From dc6076187e4f6d3a49f1baf569f6e9ae1ed84c91 Mon Sep 17 00:00:00 2001 From: Michael Marineau Date: Sat, 18 Oct 2014 18:18:17 -0700 Subject: [PATCH 3/5] gpt: consolidate crc32 computation code The gcrypt API is overly verbose, wrap it up in a helper function to keep this rather common operation easy to use. --- grub-core/lib/gpt.c | 43 ++++++++++++++++++++++++------------------- 1 file changed, 24 insertions(+), 19 deletions(-) diff --git a/grub-core/lib/gpt.c b/grub-core/lib/gpt.c index 01df7f3e8..43a150942 100644 --- a/grub-core/lib/gpt.c +++ b/grub-core/lib/gpt.c @@ -32,22 +32,17 @@ static grub_uint8_t grub_gpt_magic[] = GRUB_GPT_HEADER_MAGIC; static grub_err_t -grub_gpt_header_crc32 (struct grub_gpt_header *gpt, grub_uint32_t *crc) +grub_gpt_lecrc32 (void *data, grub_size_t len, grub_uint32_t *crc) { grub_uint8_t *crc32_context; - grub_uint32_t old; crc32_context = grub_zalloc (GRUB_MD_CRC32->contextsize); if (!crc32_context) return grub_errno; - /* crc32 must be computed with the field cleared. */ - old = gpt->crc32; - gpt->crc32 = 0; GRUB_MD_CRC32->init (crc32_context); - GRUB_MD_CRC32->write (crc32_context, gpt, sizeof (*gpt)); + GRUB_MD_CRC32->write (crc32_context, data, len); GRUB_MD_CRC32->final (crc32_context); - gpt->crc32 = old; /* GRUB_MD_CRC32 always uses big endian, gpt is always little. */ *crc = grub_swap_bytes32 (*(grub_uint32_t *) @@ -58,6 +53,25 @@ grub_gpt_header_crc32 (struct grub_gpt_header *gpt, grub_uint32_t *crc) return GRUB_ERR_NONE; } +static grub_err_t +grub_gpt_header_lecrc32 (struct grub_gpt_header *header, grub_uint32_t *crc) +{ + grub_uint32_t old, new; + grub_err_t err; + + /* crc32 must be computed with the field cleared. */ + old = header->crc32; + header->crc32 = 0; + err = grub_gpt_lecrc32 (header, sizeof (*header), &new); + header->crc32 = old; + + if (err) + return err; + + *crc = new; + return GRUB_ERR_NONE; +} + /* Make sure the MBR is a protective MBR and not a normal MBR. */ grub_err_t grub_gpt_pmbr_check (struct grub_msdos_partition_mbr *mbr) @@ -87,7 +101,7 @@ grub_gpt_header_check (struct grub_gpt_header *gpt, if (gpt->version != GRUB_GPT_HEADER_VERSION) return grub_error (GRUB_ERR_BAD_PART_TABLE, "unknown GPT version"); - if (grub_gpt_header_crc32 (gpt, &crc)) + if (grub_gpt_header_lecrc32 (gpt, &crc)) return grub_errno; if (gpt->crc32 != crc) @@ -158,7 +172,6 @@ grub_gpt_read_entries (grub_disk_t disk, grub_gpt_t gpt, struct grub_gpt_header *header) { struct grub_gpt_partentry *entries = NULL; - grub_uint8_t *crc32_context = NULL; grub_uint32_t count, size, crc; grub_disk_addr_t addr; grub_size_t entries_size; @@ -185,22 +198,15 @@ grub_gpt_read_entries (grub_disk_t disk, grub_gpt_t gpt, if (grub_disk_read (disk, addr, 0, entries_size, entries)) goto fail; - crc32_context = grub_zalloc (GRUB_MD_CRC32->contextsize); - if (!crc32_context) + if (grub_gpt_lecrc32 (entries, entries_size, &crc)) goto fail; - GRUB_MD_CRC32->init (crc32_context); - GRUB_MD_CRC32->write (crc32_context, entries, entries_size); - GRUB_MD_CRC32->final (crc32_context); - - crc = *(grub_uint32_t *) GRUB_MD_CRC32->read (crc32_context); - if (grub_swap_bytes32 (crc) != header->partentry_crc32) + if (crc != header->partentry_crc32) { grub_error (GRUB_ERR_BAD_PART_TABLE, "invalid GPT entry crc32"); goto fail; } - grub_free (crc32_context); grub_free (gpt->entries); gpt->entries = entries; gpt->entries_size = entries_size; @@ -208,7 +214,6 @@ grub_gpt_read_entries (grub_disk_t disk, grub_gpt_t gpt, fail: grub_free (entries); - grub_free (crc32_context); return grub_errno; } From 478458d404eb8663d247e04ff12cb39a5c5f8558 Mon Sep 17 00:00:00 2001 From: Michael Marineau Date: Sat, 18 Oct 2014 18:21:07 -0700 Subject: [PATCH 4/5] gpt: add new repair function to sync up primary and backup tables. --- grub-core/lib/gpt.c | 90 ++++++++++++++++++++++++++++++++++++ include/grub/gpt_partition.h | 3 ++ tests/gpt_unit_test.c | 49 ++++++++++++++++++++ 3 files changed, 142 insertions(+) diff --git a/grub-core/lib/gpt.c b/grub-core/lib/gpt.c index 43a150942..2d61df488 100644 --- a/grub-core/lib/gpt.c +++ b/grub-core/lib/gpt.c @@ -31,6 +31,20 @@ GRUB_MOD_LICENSE ("GPLv3+"); static grub_uint8_t grub_gpt_magic[] = GRUB_GPT_HEADER_MAGIC; +static grub_uint64_t +grub_gpt_size_to_sectors (grub_gpt_t gpt, grub_size_t size) +{ + unsigned int sector_size; + grub_uint64_t sectors; + + sector_size = 1U << gpt->log_sector_size; + sectors = size / sector_size; + if (size % sector_size) + sectors++; + + return sectors; +} + static grub_err_t grub_gpt_lecrc32 (void *data, grub_size_t len, grub_uint32_t *crc) { @@ -275,6 +289,82 @@ fail: return NULL; } +grub_err_t +grub_gpt_repair (grub_disk_t disk, grub_gpt_t gpt) +{ + grub_uint64_t backup_header, backup_entries; + grub_uint32_t crc; + + if (disk->log_sector_size != gpt->log_sector_size) + return grub_error (GRUB_ERR_NOT_IMPLEMENTED_YET, + "GPT sector size must match disk sector size"); + + if (!(gpt->status & GRUB_GPT_PRIMARY_ENTRIES_VALID || + gpt->status & GRUB_GPT_BACKUP_ENTRIES_VALID)) + return grub_error (GRUB_ERR_BUG, "No valid GPT entries"); + + if (gpt->status & GRUB_GPT_PRIMARY_HEADER_VALID) + { + backup_header = grub_le_to_cpu64 (gpt->primary.alternate_lba); + grub_memcpy (&gpt->backup, &gpt->primary, sizeof (gpt->backup)); + } + else if (gpt->status & GRUB_GPT_BACKUP_HEADER_VALID) + { + backup_header = grub_le_to_cpu64 (gpt->backup.header_lba); + grub_memcpy (&gpt->primary, &gpt->backup, sizeof (gpt->primary)); + } + else + return grub_error (GRUB_ERR_BUG, "No valid GPT header"); + + /* Relocate backup to end if disk whenever possible. */ + if (disk->total_sectors != GRUB_DISK_SIZE_UNKNOWN) + backup_header = disk->total_sectors - 1; + + backup_entries = backup_header - + grub_gpt_size_to_sectors (gpt, gpt->entries_size); + + /* Update/fixup header and partition table locations. */ + gpt->primary.header_lba = grub_cpu_to_le64_compile_time (1); + gpt->primary.alternate_lba = grub_cpu_to_le64 (backup_header); + gpt->primary.partitions = grub_cpu_to_le64_compile_time (2); + gpt->backup.header_lba = gpt->primary.alternate_lba; + gpt->backup.alternate_lba = gpt->primary.header_lba; + gpt->backup.partitions = grub_cpu_to_le64 (backup_entries); + + /* Writing headers larger than our header structure are unsupported. */ + gpt->primary.headersize = + grub_cpu_to_le32_compile_time (sizeof (gpt->primary)); + gpt->backup.headersize = + grub_cpu_to_le32_compile_time (sizeof (gpt->backup)); + + /* Recompute checksums. */ + if (grub_gpt_lecrc32 (gpt->entries, gpt->entries_size, &crc)) + return grub_errno; + + gpt->primary.partentry_crc32 = crc; + gpt->backup.partentry_crc32 = crc; + + if (grub_gpt_header_lecrc32 (&gpt->primary, &gpt->primary.crc32)) + return grub_errno; + + if (grub_gpt_header_lecrc32 (&gpt->backup, &gpt->backup.crc32)) + return grub_errno; + + /* Sanity check. */ + if (grub_gpt_header_check (&gpt->primary, gpt->log_sector_size)) + return grub_error (GRUB_ERR_BUG, "Generated invalid GPT primary header"); + + if (grub_gpt_header_check (&gpt->backup, gpt->log_sector_size)) + return grub_error (GRUB_ERR_BUG, "Generated invalid GPT backup header"); + + gpt->status |= (GRUB_GPT_PRIMARY_HEADER_VALID | + GRUB_GPT_PRIMARY_ENTRIES_VALID | + GRUB_GPT_BACKUP_HEADER_VALID | + GRUB_GPT_BACKUP_ENTRIES_VALID); + + return GRUB_ERR_NONE; +} + void grub_gpt_free (grub_gpt_t gpt) { diff --git a/include/grub/gpt_partition.h b/include/grub/gpt_partition.h index 7f41e22dd..62d027e4e 100644 --- a/include/grub/gpt_partition.h +++ b/include/grub/gpt_partition.h @@ -141,6 +141,9 @@ grub_gpt_sector_to_addr (grub_gpt_t gpt, grub_uint64_t sector) /* Allocates and fills new grub_gpt structure, free with grub_gpt_free. */ grub_gpt_t grub_gpt_read (grub_disk_t disk); +/* Sync up primary and backup headers, recompute checksums. */ +grub_err_t grub_gpt_repair (grub_disk_t disk, grub_gpt_t gpt); + void grub_gpt_free (grub_gpt_t gpt); grub_err_t grub_gpt_pmbr_check (struct grub_msdos_partition_mbr *mbr); diff --git a/tests/gpt_unit_test.c b/tests/gpt_unit_test.c index 4d70868af..83198bebf 100644 --- a/tests/gpt_unit_test.c +++ b/tests/gpt_unit_test.c @@ -24,6 +24,7 @@ #include #include #include +#include #include #include @@ -442,6 +443,52 @@ read_fallback_test (void) close_disk (&data); } +static void +repair_test (void) +{ + struct test_data data; + grub_gpt_t gpt; + + open_disk (&data); + + /* Erase/Repair primary. */ + memset (&data.raw->primary_header, 0, sizeof (data.raw->primary_header)); + sync_disk (&data); + gpt = read_disk (&data); + grub_gpt_repair (data.dev->disk, gpt); + grub_test_assert (grub_errno == GRUB_ERR_NONE, + "repair failed: %s", grub_errmsg); + if (memcmp (&gpt->primary, &example_primary, sizeof (gpt->primary))) + { + printf ("Invalid restored primary header:\n"); + hexdump (16, (char*)&gpt->primary, sizeof (gpt->primary)); + printf ("Expected primary header:\n"); + hexdump (16, (char*)&example_primary, sizeof (example_primary)); + grub_test_assert (0, "repair did not restore primary header"); + } + grub_gpt_free (gpt); + reset_disk (&data); + + /* Erase/Repair backup. */ + memset (&data.raw->backup_header, 0, sizeof (data.raw->backup_header)); + sync_disk (&data); + gpt = read_disk (&data); + grub_gpt_repair (data.dev->disk, gpt); + grub_test_assert (grub_errno == GRUB_ERR_NONE, + "repair failed: %s", grub_errmsg); + if (memcmp (&gpt->backup, &example_backup, sizeof (gpt->backup))) + { + printf ("Invalid restored backup header:\n"); + hexdump (16, (char*)&gpt->backup, sizeof (gpt->backup)); + printf ("Expected backup header:\n"); + hexdump (16, (char*)&example_backup, sizeof (example_backup)); + grub_test_assert (0, "repair did not restore backup header"); + } + grub_gpt_free (gpt); + reset_disk (&data); + + close_disk (&data); +} void grub_unit_test_init (void) { @@ -453,6 +500,7 @@ grub_unit_test_init (void) grub_test_register ("gpt_read_valid_test", read_valid_test); grub_test_register ("gpt_read_invalid_test", read_invalid_entries_test); grub_test_register ("gpt_read_fallback_test", read_fallback_test); + grub_test_register ("gpt_repair_test", repair_test); } void @@ -463,5 +511,6 @@ grub_unit_test_fini (void) grub_test_unregister ("gpt_read_valid_test"); grub_test_unregister ("gpt_read_invalid_test"); grub_test_unregister ("gpt_read_fallback_test"); + grub_test_unregister ("gpt_repair_test"); grub_fini_all (); } From 051545ddf045af88057fc6ae63718c6eca92538e Mon Sep 17 00:00:00 2001 From: Michael Marineau Date: Sun, 19 Oct 2014 14:21:29 -0700 Subject: [PATCH 5/5] gpt: add write function and gptrepair command The first hint of something practical, a command that can restore any of the GPT structures from the alternate location. New test case must run under QEMU because the loopback device used by the other unit tests does not support writing. --- Makefile.util.def | 6 ++ grub-core/Makefile.core.def | 5 ++ grub-core/commands/gptrepair.c | 116 +++++++++++++++++++++++++++++++++ grub-core/lib/gpt.c | 44 +++++++++++-- include/grub/gpt_partition.h | 8 +++ tests/gptrepair_test.in | 102 +++++++++++++++++++++++++++++ 6 files changed, 277 insertions(+), 4 deletions(-) create mode 100644 grub-core/commands/gptrepair.c create mode 100644 tests/gptrepair_test.in diff --git a/Makefile.util.def b/Makefile.util.def index f3a8aec17..ab056f8ac 100644 --- a/Makefile.util.def +++ b/Makefile.util.def @@ -1150,6 +1150,12 @@ script = { common = tests/grub_cmd_tr.in; }; +script = { + testcase; + name = gptrepair_test; + common = tests/gptrepair_test.in; +}; + program = { testcase; name = example_unit_test; diff --git a/grub-core/Makefile.core.def b/grub-core/Makefile.core.def index 385f53f59..7f309b830 100644 --- a/grub-core/Makefile.core.def +++ b/grub-core/Makefile.core.def @@ -826,6 +826,11 @@ module = { common = commands/gptsync.c; }; +module = { + name = gptrepair; + common = commands/gptrepair.c; +}; + module = { name = gpt; common = lib/gpt.c; diff --git a/grub-core/commands/gptrepair.c b/grub-core/commands/gptrepair.c new file mode 100644 index 000000000..38392fd8f --- /dev/null +++ b/grub-core/commands/gptrepair.c @@ -0,0 +1,116 @@ +/* gptrepair.c - verify and restore GPT info from alternate location. */ +/* + * GRUB -- GRand Unified Bootloader + * Copyright (C) 2009 Free Software Foundation, Inc. + * Copyright (C) 2014 CoreOS, Inc. + * + * GRUB is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, either version 3 of the License, or + * (at your option) any later version. + * + * GRUB is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with GRUB. If not, see . + */ + +#include +#include +#include +#include +#include +#include + +GRUB_MOD_LICENSE ("GPLv3+"); + +static char * +trim_dev_name (char *name) +{ + grub_size_t len = grub_strlen (name); + if (len && name[0] == '(' && name[len - 1] == ')') + { + name[len - 1] = '\0'; + name = name + 1; + } + return name; +} + +static grub_err_t +grub_cmd_gptrepair (grub_command_t cmd __attribute__ ((unused)), + int argc, char **args) +{ + grub_device_t dev = NULL; + grub_gpt_t gpt = NULL; + char *dev_name; + grub_uint32_t primary_crc, backup_crc; + enum grub_gpt_status old_status; + + if (argc != 1 || !grub_strlen(args[0])) + return grub_error (GRUB_ERR_BAD_ARGUMENT, "device name required"); + + dev_name = trim_dev_name (args[0]); + dev = grub_device_open (dev_name); + if (!dev) + goto done; + + if (!dev->disk) + { + grub_error (GRUB_ERR_BAD_ARGUMENT, "not a disk"); + goto done; + } + + gpt = grub_gpt_read (dev->disk); + if (!gpt) + goto done; + + primary_crc = gpt->primary.crc32; + backup_crc = gpt->backup.crc32; + old_status = gpt->status; + + if (grub_gpt_repair (dev->disk, gpt)) + goto done; + + if (primary_crc == gpt->primary.crc32 && + backup_crc == gpt->backup.crc32 && + old_status && gpt->status) + { + grub_printf_ (N_("GPT already valid, %s unmodified.\n"), dev_name); + goto done; + } + + if (grub_gpt_write (dev->disk, gpt)) + goto done; + + if (!(old_status & GRUB_GPT_PRIMARY_VALID)) + grub_printf_ (N_("Primary GPT for %s repaired.\n"), dev_name); + + if (!(old_status & GRUB_GPT_BACKUP_VALID)) + grub_printf_ (N_("Backup GPT for %s repaired.\n"), dev_name); + +done: + if (gpt) + grub_gpt_free (gpt); + + if (dev) + grub_device_close (dev); + + return grub_errno; +} + +static grub_command_t cmd; + +GRUB_MOD_INIT(gptrepair) +{ + cmd = grub_register_command ("gptrepair", grub_cmd_gptrepair, + N_("DEVICE"), + N_("Verify and repair GPT on drive DEVICE.")); +} + +GRUB_MOD_FINI(gptrepair) +{ + grub_unregister_command (cmd); +} diff --git a/grub-core/lib/gpt.c b/grub-core/lib/gpt.c index 2d61df488..67ffdf703 100644 --- a/grub-core/lib/gpt.c +++ b/grub-core/lib/gpt.c @@ -357,10 +357,46 @@ grub_gpt_repair (grub_disk_t disk, grub_gpt_t gpt) if (grub_gpt_header_check (&gpt->backup, gpt->log_sector_size)) return grub_error (GRUB_ERR_BUG, "Generated invalid GPT backup header"); - gpt->status |= (GRUB_GPT_PRIMARY_HEADER_VALID | - GRUB_GPT_PRIMARY_ENTRIES_VALID | - GRUB_GPT_BACKUP_HEADER_VALID | - GRUB_GPT_BACKUP_ENTRIES_VALID); + gpt->status |= GRUB_GPT_BOTH_VALID; + return GRUB_ERR_NONE; +} + +static grub_err_t +grub_gpt_write_table (grub_disk_t disk, grub_gpt_t gpt, + struct grub_gpt_header *header) +{ + grub_disk_addr_t addr; + + if (grub_le_to_cpu32 (header->headersize) != sizeof (*header)) + return grub_error (GRUB_ERR_NOT_IMPLEMENTED_YET, + "Header size is %u, must be %u", + grub_le_to_cpu32 (header->headersize), + sizeof (*header)); + + addr = grub_gpt_sector_to_addr (gpt, grub_le_to_cpu64 (header->header_lba)); + if (grub_disk_write (disk, addr, 0, sizeof (*header), header)) + return grub_errno; + + addr = grub_gpt_sector_to_addr (gpt, grub_le_to_cpu64 (header->partitions)); + if (grub_disk_write (disk, addr, 0, gpt->entries_size, gpt->entries)) + return grub_errno; + + return GRUB_ERR_NONE; +} + +grub_err_t +grub_gpt_write (grub_disk_t disk, grub_gpt_t gpt) +{ + /* TODO: update/repair protective MBRs too. */ + + if (!(gpt->status & GRUB_GPT_BOTH_VALID)) + return grub_error (GRUB_ERR_BAD_PART_TABLE, "Invalid GPT data"); + + if (grub_gpt_write_table (disk, gpt, &gpt->primary)) + return grub_errno; + + if (grub_gpt_write_table (disk, gpt, &gpt->backup)) + return grub_errno; return GRUB_ERR_NONE; } diff --git a/include/grub/gpt_partition.h b/include/grub/gpt_partition.h index 62d027e4e..3cac6df32 100644 --- a/include/grub/gpt_partition.h +++ b/include/grub/gpt_partition.h @@ -103,6 +103,11 @@ typedef enum grub_gpt_status } grub_gpt_status_t; #define GRUB_GPT_MBR_VALID (GRUB_GPT_PROTECTIVE_MBR|GRUB_GPT_HYBRID_MBR) +#define GRUB_GPT_PRIMARY_VALID \ + (GRUB_GPT_PRIMARY_HEADER_VALID|GRUB_GPT_PRIMARY_ENTRIES_VALID) +#define GRUB_GPT_BACKUP_VALID \ + (GRUB_GPT_BACKUP_HEADER_VALID|GRUB_GPT_BACKUP_ENTRIES_VALID) +#define GRUB_GPT_BOTH_VALID (GRUB_GPT_PRIMARY_VALID|GRUB_GPT_BACKUP_VALID) /* UEFI requires the entries table to be at least 16384 bytes for a * total of 128 entries given the standard 128 byte entry size. */ @@ -144,6 +149,9 @@ grub_gpt_t grub_gpt_read (grub_disk_t disk); /* Sync up primary and backup headers, recompute checksums. */ grub_err_t grub_gpt_repair (grub_disk_t disk, grub_gpt_t gpt); +/* Write headers and entry tables back to disk. */ +grub_err_t grub_gpt_write (grub_disk_t disk, grub_gpt_t gpt); + void grub_gpt_free (grub_gpt_t gpt); grub_err_t grub_gpt_pmbr_check (struct grub_msdos_partition_mbr *mbr); diff --git a/tests/gptrepair_test.in b/tests/gptrepair_test.in new file mode 100644 index 000000000..80b2de633 --- /dev/null +++ b/tests/gptrepair_test.in @@ -0,0 +1,102 @@ +#! /bin/sh +set -e + +# Copyright (C) 2010 Free Software Foundation, Inc. +# Copyright (C) 2014 CoreOS, Inc. +# +# GRUB is free software: you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation, either version 3 of the License, or +# (at your option) any later version. +# +# GRUB is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with GRUB. If not, see . + +parted=parted +grubshell=@builddir@/grub-shell + +. "@builddir@/grub-core/modinfo.sh" + +case "${grub_modinfo_target_cpu}-${grub_modinfo_platform}" in + mips-qemu_mips | mipsel-qemu_mips | i386-qemu | i386-multiboot | i386-coreboot | mipsel-loongson) + disk=ata0 + ;; + powerpc-ieee1275) + disk=ieee1275//pci@80000000/mac-io@4/ata-3@20000/disk@0 + # FIXME: QEMU firmware has bugs which prevent it from accessing hard disk w/o recognised label. + exit 0 + ;; + sparc64-ieee1275) + disk=ieee1275//pci@1fe\,0/pci-ata@5/ide0@500/disk@0 + # FIXME: QEMU firmware has bugs which prevent it from accessing hard disk w/o recognised label. + exit 0 + ;; + i386-ieee1275) + disk=ieee1275/d + # FIXME: QEMU firmware has bugs which prevent it from accessing hard disk w/o recognised label. + exit 0 + ;; + mips-arc) + # FIXME: ARC firmware has bugs which prevent it from accessing hard disk w/o dvh disklabel. + exit 0 ;; + mipsel-arc) + disk=arc/scsi0/disk0/rdisk0 + ;; + *) + disk=hd0 + ;; +esac +img1="`mktemp "${TMPDIR:-/tmp}/tmp.XXXXXXXXXX"`" || exit 1 +img2="`mktemp "${TMPDIR:-/tmp}/tmp.XXXXXXXXXX"`" || exit 1 +trap "rm -f '${img1}' '${ing2}'" EXIT + +create_disk_image () { + size=$1 + rm -f "${img1}" + dd if=/dev/zero of="${img1}" bs=512 count=1 seek=$((size - 1)) status=none + ${parted} -a none -s "${img1}" mklabel gpt + cp "${img1}" "${img2}" +} + +wipe_disk_area () { + sector=$1 + size=$2 + dd if=/dev/zero of="${img2}" bs=512 count=${size} seek=${sector} conv=notrunc status=none +} + +do_repair () { + output="`echo "gptrepair ($disk)" | "${grubshell}" --disk="${img2}"`" + if echo "${output}" | grep ^error; then + return 1 + fi + if echo "${output}" | grep -v GPT; then + echo "Unexpected output ${output}" + return 1 + fi + echo "${output}" +} + +echo "Nothing to repair:" +create_disk_image 100 +do_repair +cmp "${img1}" "${img2}" +echo + +echo "Repair primary (MBR left intact)" +create_disk_image 100 +wipe_disk_area 1 1 +do_repair +cmp "${img1}" "${img2}" +echo + +echo "Repair backup" +create_disk_image 100 +wipe_disk_area 99 1 +do_repair +cmp "${img1}" "${img2}" +echo