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-rw-r--r--grub-core/partmap/msdos.c435
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diff --git a/grub-core/partmap/msdos.c b/grub-core/partmap/msdos.c
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+++ b/grub-core/partmap/msdos.c
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+/* pc.c - Read PC style partition tables. */
+/*
+ * GRUB -- GRand Unified Bootloader
+ * Copyright (C) 2002,2004,2005,2006,2007,2008,2009 Free Software Foundation, 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 <http://www.gnu.org/licenses/>.
+ */
+
+#include <grub/partition.h>
+#include <grub/msdos_partition.h>
+#include <grub/disk.h>
+#include <grub/mm.h>
+#include <grub/misc.h>
+#include <grub/dl.h>
+#include <grub/i18n.h>
+
+GRUB_MOD_LICENSE ("GPLv3+");
+
+static struct grub_partition_map grub_msdos_partition_map;
+
+
+#ifdef GRUB_UTIL
+#include <grub/emu/misc.h>
+
+struct embed_signature
+{
+ const char *name;
+ const char *signature;
+ int signature_len;
+ enum { TYPE_SOFTWARE, TYPE_RAID } type;
+};
+
+const char message_warn[][200] = {
+ /* TRANSLATORS: MBR gap and boot track is the same thing and is the space
+ between MBR and first partitition. If your language translates well only
+ "boot track", you can just use it everywhere. Next two messages are about
+ RAID controllers/software bugs which GRUB has to live with. Please spread
+ the message that these are bugs in other software and not merely
+ suboptimal behaviour. */
+ [TYPE_RAID] = N_("Sector %llu is already in use by raid controller `%s';"
+ " avoiding it. "
+ "Please ask the manufacturer not to store data in MBR gap"),
+ [TYPE_SOFTWARE] = N_("Sector %llu is already in use by the program `%s';"
+ " avoiding it. "
+ "This software may cause boot or other problems in "
+ "future. Please ask its authors not to store data "
+ "in the boot track")
+};
+
+
+/* Signatures of other software that may be using sectors in the embedding
+ area. */
+struct embed_signature embed_signatures[] =
+ {
+ {
+ .name = "ZISD",
+ .signature = "ZISD",
+ .signature_len = 4,
+ .type = TYPE_SOFTWARE
+ },
+ {
+ .name = "FlexNet",
+ .signature = "\xd4\x41\xa0\xf5\x03\x00\x03\x00",
+ .signature_len = 8,
+ .type = TYPE_SOFTWARE
+ },
+ {
+ .name = "FlexNet",
+ .signature = "\xd8\x41\xa0\xf5\x02\x00\x02\x00",
+ .signature_len = 8,
+ .type = TYPE_SOFTWARE
+ },
+ {
+ /* from Ryan Perkins */
+ .name = "HP Backup and Recovery Manager (?)",
+ .signature = "\x70\x8a\x5d\x46\x35\xc5\x1b\x93"
+ "\xae\x3d\x86\xfd\xb1\x55\x3e\xe0",
+ .signature_len = 16,
+ .type = TYPE_SOFTWARE
+ },
+ {
+ .name = "HighPoint RAID controller",
+ .signature = "ycgl",
+ .signature_len = 4,
+ .type = TYPE_RAID
+ },
+ {
+ /* https://bugs.launchpad.net/bugs/987022 */
+ .name = "Acer registration utility (?)",
+ .signature = "GREGRegDone.Tag\x00",
+ .signature_len = 16,
+ .type = TYPE_SOFTWARE
+ }
+ };
+#endif
+
+grub_err_t
+grub_partition_msdos_iterate (grub_disk_t disk,
+ grub_partition_iterate_hook_t hook,
+ void *hook_data)
+{
+ struct grub_partition p;
+ struct grub_msdos_partition_mbr mbr;
+ int labeln = 0;
+ grub_disk_addr_t lastaddr;
+ grub_disk_addr_t ext_offset;
+ grub_disk_addr_t delta = 0;
+
+ if (disk->partition && disk->partition->partmap == &grub_msdos_partition_map)
+ {
+ if (disk->partition->msdostype == GRUB_PC_PARTITION_TYPE_LINUX_MINIX)
+ delta = disk->partition->start;
+ else
+ return grub_error (GRUB_ERR_BAD_PART_TABLE, "no embedding supported");
+ }
+
+ p.offset = 0;
+ ext_offset = 0;
+ p.number = -1;
+ p.partmap = &grub_msdos_partition_map;
+
+ /* Any value different than `p.offset' will satisfy the check during
+ first loop. */
+ lastaddr = !p.offset;
+
+ while (1)
+ {
+ int i;
+ struct grub_msdos_partition_entry *e;
+
+ /* Read the MBR. */
+ if (grub_disk_read (disk, p.offset, 0, sizeof (mbr), &mbr))
+ goto finish;
+
+ /* If this is a GPT partition, this MBR is just a dummy. */
+ if (p.offset == 0)
+ for (i = 0; i < 4; i++)
+ if (mbr.entries[i].type == GRUB_PC_PARTITION_TYPE_GPT_DISK)
+ return grub_error (GRUB_ERR_BAD_PART_TABLE, "dummy mbr");
+
+ /* This is our loop-detection algorithm. It works the following way:
+ It saves last position which was a power of two. Then it compares the
+ saved value with a current one. This way it's guaranteed that the loop
+ will be broken by at most third walk.
+ */
+ if (labeln && lastaddr == p.offset)
+ return grub_error (GRUB_ERR_BAD_PART_TABLE, "loop detected");
+
+ labeln++;
+ if ((labeln & (labeln - 1)) == 0)
+ lastaddr = p.offset;
+
+ /* Check if it is valid. */
+ if (mbr.signature != grub_cpu_to_le16_compile_time (GRUB_PC_PARTITION_SIGNATURE))
+ return grub_error (GRUB_ERR_BAD_PART_TABLE, "no signature");
+
+ for (i = 0; i < 4; i++)
+ if (mbr.entries[i].flag & 0x7f)
+ return grub_error (GRUB_ERR_BAD_PART_TABLE, "bad boot flag");
+
+ /* Analyze DOS partitions. */
+ for (p.index = 0; p.index < 4; p.index++)
+ {
+ e = mbr.entries + p.index;
+
+ p.start = p.offset
+ + ((grub_disk_addr_t)grub_le_to_cpu32 (e->start)
+ << (disk->log_sector_size - GRUB_DISK_SECTOR_BITS)) - delta;
+ p.len = (grub_uint64_t)grub_le_to_cpu32 (e->length)
+ << (disk->log_sector_size - GRUB_DISK_SECTOR_BITS);
+ p.msdostype = e->type;
+
+ grub_dprintf ("partition",
+ "partition %d: flag 0x%x, type 0x%x, start 0x%llx, len 0x%llx\n",
+ p.index, e->flag, e->type,
+ (unsigned long long) p.start,
+ (unsigned long long) p.len);
+
+ /* If this partition is a normal one, call the hook. */
+ if (! grub_msdos_partition_is_empty (e->type)
+ && ! grub_msdos_partition_is_extended (e->type))
+ {
+ p.number++;
+
+ if (hook (disk, &p, hook_data))
+ return grub_errno;
+ }
+ else if (p.number < 3)
+ /* If this partition is a logical one, shouldn't increase the
+ partition number. */
+ p.number++;
+ }
+
+ /* Find an extended partition. */
+ for (i = 0; i < 4; i++)
+ {
+ e = mbr.entries + i;
+
+ if (grub_msdos_partition_is_extended (e->type))
+ {
+ p.offset = ext_offset
+ + ((grub_disk_addr_t)grub_le_to_cpu32 (e->start)
+ << (disk->log_sector_size - GRUB_DISK_SECTOR_BITS));
+ if (! ext_offset)
+ ext_offset = p.offset;
+
+ break;
+ }
+ }
+
+ /* If no extended partition, the end. */
+ if (i == 4)
+ break;
+ }
+
+ finish:
+ return grub_errno;
+}
+
+#ifdef GRUB_UTIL
+
+#pragma GCC diagnostic ignored "-Wformat-nonliteral"
+
+static grub_err_t
+pc_partition_map_embed (struct grub_disk *disk, unsigned int *nsectors,
+ unsigned int max_nsectors,
+ grub_embed_type_t embed_type,
+ grub_disk_addr_t **sectors,
+ int warn_short)
+{
+ grub_disk_addr_t end = ~0ULL;
+ struct grub_msdos_partition_mbr mbr;
+ int labeln = 0;
+ /* Any value different than `p.offset' will satisfy the check during
+ first loop. */
+ grub_disk_addr_t lastaddr = 1;
+ grub_disk_addr_t ext_offset = 0;
+ grub_disk_addr_t offset = 0;
+
+ if (embed_type != GRUB_EMBED_PCBIOS)
+ return grub_error (GRUB_ERR_NOT_IMPLEMENTED_YET,
+ "PC-style partitions currently support "
+ "only PC-BIOS embedding");
+
+ if (disk->partition)
+ return grub_error (GRUB_ERR_OUT_OF_RANGE,
+ "Embedding on MSDOS subpartition isn't supported");
+
+ while (1)
+ {
+ int i;
+ struct grub_msdos_partition_entry *e;
+ grub_err_t err;
+
+ /* Read the MBR. */
+ err = grub_disk_read (disk, offset, 0, sizeof (mbr), &mbr);
+ if (err)
+ return err;
+
+ /* This is our loop-detection algorithm. It works the following way:
+ It saves last position which was a power of two. Then it compares the
+ saved value with a current one. This way it's guaranteed that the loop
+ will be broken by at most third walk.
+ */
+ if (labeln && lastaddr == offset)
+ return grub_error (GRUB_ERR_BAD_PART_TABLE, "loop detected");
+
+ labeln++;
+ if ((labeln & (labeln - 1)) == 0)
+ lastaddr = offset;
+
+ /* Check if it is valid. */
+ if (mbr.signature != grub_cpu_to_le16_compile_time (GRUB_PC_PARTITION_SIGNATURE))
+ return grub_error (GRUB_ERR_BAD_PART_TABLE, "no signature");
+
+ for (i = 0; i < 4; i++)
+ if (mbr.entries[i].flag & 0x7f)
+ return grub_error (GRUB_ERR_BAD_PART_TABLE, "bad boot flag");
+
+ /* Analyze DOS partitions. */
+ for (i = 0; i < 4; i++)
+ {
+ e = mbr.entries + i;
+
+ if (!grub_msdos_partition_is_empty (e->type)
+ && end > offset
+ + ((grub_disk_addr_t)grub_le_to_cpu32 (e->start)
+ << (disk->log_sector_size - GRUB_DISK_SECTOR_BITS)))
+ end = offset + ((grub_disk_addr_t)grub_le_to_cpu32 (e->start)
+ << (disk->log_sector_size - GRUB_DISK_SECTOR_BITS));
+
+ /* If this is a GPT partition, this MBR is just a dummy. */
+ if (e->type == GRUB_PC_PARTITION_TYPE_GPT_DISK && i == 0)
+ return grub_error (GRUB_ERR_BAD_PART_TABLE, "dummy mbr");
+ }
+
+ /* Find an extended partition. */
+ for (i = 0; i < 4; i++)
+ {
+ e = mbr.entries + i;
+
+ if (grub_msdos_partition_is_extended (e->type))
+ {
+ offset = ext_offset
+ + ((grub_disk_addr_t)grub_le_to_cpu32 (e->start)
+ << (disk->log_sector_size - GRUB_DISK_SECTOR_BITS));
+ if (! ext_offset)
+ ext_offset = offset;
+
+ break;
+ }
+ }
+
+ /* If no extended partition, the end. */
+ if (i == 4)
+ break;
+ }
+
+ if (end >= *nsectors + 1)
+ {
+ unsigned i, j;
+ char *embed_signature_check;
+ unsigned int orig_nsectors, avail_nsectors;
+
+ orig_nsectors = *nsectors;
+ *nsectors = end - 1;
+ avail_nsectors = *nsectors;
+ if (*nsectors > max_nsectors)
+ *nsectors = max_nsectors;
+ *sectors = grub_calloc (*nsectors, sizeof (**sectors));
+ if (!*sectors)
+ return grub_errno;
+ for (i = 0; i < *nsectors; i++)
+ (*sectors)[i] = 1 + i;
+
+ /* Check for software that is already using parts of the embedding
+ * area.
+ */
+ embed_signature_check = grub_malloc (GRUB_DISK_SECTOR_SIZE);
+ for (i = 0; i < *nsectors; i++)
+ {
+ if (grub_disk_read (disk, (*sectors)[i], 0, GRUB_DISK_SECTOR_SIZE,
+ embed_signature_check))
+ continue;
+
+ for (j = 0; j < ARRAY_SIZE (embed_signatures); j++)
+ if (! grub_memcmp (embed_signatures[j].signature,
+ embed_signature_check,
+ embed_signatures[j].signature_len))
+ break;
+ if (j == ARRAY_SIZE (embed_signatures))
+ continue;
+ grub_util_warn (_(message_warn[embed_signatures[j].type]),
+ (*sectors)[i], embed_signatures[j].name);
+ avail_nsectors--;
+ if (avail_nsectors < *nsectors)
+ *nsectors = avail_nsectors;
+
+ /* Avoid this sector. */
+ for (j = i; j < *nsectors; j++)
+ (*sectors)[j]++;
+
+ /* Have we run out of space? */
+ if (avail_nsectors < orig_nsectors)
+ break;
+
+ /* Make sure to check the next sector. */
+ i--;
+ }
+ grub_free (embed_signature_check);
+
+ if (*nsectors < orig_nsectors)
+ return grub_error (GRUB_ERR_OUT_OF_RANGE,
+ N_("other software is using the embedding area, and "
+ "there is not enough room for core.img. Such "
+ "software is often trying to store data in a way "
+ "that avoids detection. We recommend you "
+ "investigate"));
+
+ return GRUB_ERR_NONE;
+ }
+
+ if (end < GRUB_MIN_RECOMMENDED_MBR_GAP && warn_short)
+ grub_util_warn ("You have a short MBR gap and use advanced config. Please increase post-MBR gap.");
+
+ if (end <= 1)
+ return grub_error (GRUB_ERR_FILE_NOT_FOUND,
+ N_("this msdos-style partition label has no "
+ "post-MBR gap; embedding won't be possible"));
+
+ if (*nsectors > 62)
+ return grub_error (GRUB_ERR_OUT_OF_RANGE,
+ N_("your core.img is unusually large. "
+ "It won't fit in the embedding area"));
+
+ return grub_error (GRUB_ERR_OUT_OF_RANGE,
+ N_("your embedding area is unusually small. "
+ "core.img won't fit in it."));
+}
+
+#pragma GCC diagnostic error "-Wformat-nonliteral"
+
+#endif
+
+
+/* Partition map type. */
+static struct grub_partition_map grub_msdos_partition_map =
+ {
+ .name = "msdos",
+ .iterate = grub_partition_msdos_iterate,
+#ifdef GRUB_UTIL
+ .embed = pc_partition_map_embed
+#endif
+ };
+
+GRUB_MOD_INIT(part_msdos)
+{
+ grub_partition_map_register (&grub_msdos_partition_map);
+}
+
+GRUB_MOD_FINI(part_msdos)
+{
+ grub_partition_map_unregister (&grub_msdos_partition_map);
+}
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