linux-ext4 - [PATCH] libblkid: support for GUID Partition Table (GPT), please?

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-ID: <87632ql0pg.fsf@violet.siamics.net>
Date:	Sat, 15 May 2010 02:53:15 +0700
From:	Ivan Shmakov <ivan@...n.uusia.org>
To:	linux-ext4@...r.kernel.org
Cc:	Ivan Shmakov <oneingray@...il.com>
Subject: [PATCH] libblkid: support for GUID Partition Table (GPT), please?

	GPT contains a supposed to be unique “Disk GUID” field, which
	allows for the media bearing such a partition table to be
	identified.

	May I suggest adding support for GPT to libblkid?  An
	alpha-quality patch is MIME'd.

-- 
FSF associate member #7257

diff --git a/lib/blkid/probe.c b/lib/blkid/probe.c
index 6b75732..0e6c70d 100644
--- a/lib/blkid/probe.c
+++ b/lib/blkid/probe.c
@@ -1383,6 +1383,28 @@ static int probe_btrfs(struct blkid_probe *probe,
 	set_uuid(probe->dev, bs->fsid, 0);
 	return 0;
 }
+
+static int probe_gpt (struct blkid_probe *probe,
+                      struct blkid_magic *id,
+                      unsigned char *buf)
+{
+	struct gpt_header *gh
+		= (struct gpt_header *)(buf + 0x200);
+
+	/* FIXME: check gh->header_crc32 */
+
+	{
+		__u64 uuid;
+		char uuid_str[17];
+
+		uuid = blkid_le64 (*((__u64 *)gh->disk_guid));
+		sprintf (uuid_str, "%016llX", uuid);
+		blkid_set_tag (probe->dev, "UUID", uuid_str, 0);
+	}
+
+	return 0;
+}
+
 /*
  * Various filesystem magics that we can check for.  Note that kboff and
  * sboff are in kilobytes and bytes respectively.  All magics are in
@@ -1482,6 +1504,7 @@ static struct blkid_magic type_array[] = {
   { "lvm2pv",	 1,  0x018,  8, "LVM2 001",		probe_lvm2 },
   { "lvm2pv",	 1,  0x218,  8, "LVM2 001",		probe_lvm2 },
   { "btrfs",	 64,  0x40,  8, "_BHRfS_M",		probe_btrfs },
+  { "gpt",       0,  0x200,  8, "EFI PART",             probe_gpt },
   {   NULL,	 0,	 0,  0, NULL,			NULL }
 };
 
diff --git a/lib/blkid/probe.h b/lib/blkid/probe.h
index 37fc9c0..4d39b84 100644
--- a/lib/blkid/probe.h
+++ b/lib/blkid/probe.h
@@ -725,6 +725,28 @@ struct btrfs_super_block {
 	__u8 sys_chunk_array[BTRFS_SYSTEM_CHUNK_ARRAY_SIZE];
 } __attribute__ ((__packed__));
 
+struct gpt_header {
+	/* references:
+	 *   * linux/include/linux/efi.h;
+	 *   * Wikipedia entry.
+	 */
+	__u64 signature;
+	__u32 revision;
+	__u32 header_size;
+	__u32 header_crc32;
+	__u32 reserved1;
+	__u64 my_lba;
+	__u64 alternate_lba;
+	__u64 first_usable_lba;
+	__u64 last_usable_lba;
+	__u8 disk_guid[16];
+	__u64 partition_entry_lba;
+	__u32 num_partition_entries;
+	__u32 sizeof_partition_entry;
+	__u32 partition_entry_array_crc32;
+	__u8 reserved2[512 - 92];
+} __attribute__ ((__packed__));
+
 /*
  * Byte swap functions
  */


Content of type "application/pgp-signature" skipped