keep GUID specific attributes

Keep GUID specific attributes when writing GPT.

Signed-off-by: Brian C. Lane <bcl@redhat.com>

3 files changed, 120 insertions, 1 deletions

diff --git a/tests/Makefile.am b/tests/Makefile.am
index f9340aa..3dc6e72 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -26,6 +26,7 @@ TESTS = \
   t0211-gpt-rewrite-header.sh \
   t0212-gpt-many-partitions.sh \
   t0213-mkpart-start-negative.sh \
+  t0215-gpt-attrs.sh \
   t0220-gpt-msftres.sh \
   t0250-gpt.sh \
   t0251-gpt-unicode.sh \
@@ -98,7 +99,7 @@ TESTS = \
 EXTRA_DIST = \
   $(TESTS) t-local.sh t-lvm.sh \
   init.cfg init.sh t-lib-helpers.sh gpt-header-munge \
-  gpt-header-move msdos-overlap
+  gpt-header-move msdos-overlap gpt-attrs
 
 check_PROGRAMS = print-align print-flags print-max dup-clobber duplicate \
   fs-resize
diff --git a/tests/gpt-attrs b/tests/gpt-attrs
new file mode 100755
index 0000000..0a01447
--- /dev/null
+++ b/tests/gpt-attrs
@@ -0,0 +1,72 @@
+#!/usr/bin/python3
+
+# Copyright (C) 2021 SUSE LLC
+
+# program to show gpt partition attributes or set attributes of
+# partition 1
+
+# only works with 512 sectors and standard GPT header layout (128
+# partition entires with 128 bytes each, secondary header at end of
+# device)
+
+
+from struct import unpack_from, pack_into
+from zipfile import crc32
+import array
+import sys
+
+
+class Gpt:
+
+    # Calculate and insert the CRCs of the partition entires and the
+    # header.
+    def calc_crcs(self, header, entries):
+        # compute crc of partition entries
+        crc2 = crc32(entries) & 0xFFFFFFFF
+        pack_into('<L', header, 88, crc2)
+
+        # compute crc of header
+        pack_into('<L', header, 16, 0)
+        crc1 = crc32(header[:92]) & 0xFFFFFFFF
+        pack_into('<L', header, 16, crc1)
+
+    def read(self, name):
+        self.name = name
+
+        file = open(name, 'rb+')
+
+        file.seek(512)
+        self.primary_header = array.array('B', file.read(512))
+        self.primary_entries = array.array('B', file.read(32 * 512))
+
+        file.seek(-33 * 512, 2)
+        self.secondary_entries = array.array('B', file.read(32 * 512))
+        self.secondary_header = array.array('B', file.read(512))
+
+    def write(self):
+        file = open(self.name, 'rb+')
+
+        self.calc_crcs(self.primary_header, self.primary_entries)
+        file.seek(512)
+        file.write(self.primary_header)
+        file.write(self.primary_entries)
+
+        self.calc_crcs(self.secondary_header, self.secondary_entries)
+        file.seek(-33 * 512, 2)
+        file.write(self.secondary_entries)
+        file.write(self.secondary_header)
+
+
+gpt = Gpt()
+
+gpt.read(sys.argv[1])
+
+if sys.argv[2] == "show":
+    attrs = unpack_from('<Q', gpt.primary_entries, 48)[0]
+    print(hex(attrs))
+
+if sys.argv[2] == "set":
+    attrs = int(sys.argv[3], 0)
+    pack_into('<Q', gpt.primary_entries, 48, attrs)
+    pack_into('<Q', gpt.secondary_entries, 48, attrs)
+    gpt.write()
diff --git a/tests/t0215-gpt-attrs.sh b/tests/t0215-gpt-attrs.sh
new file mode 100644
index 0000000..216a966
--- /dev/null
+++ b/tests/t0215-gpt-attrs.sh
@@ -0,0 +1,46 @@
+#!/bin/sh
+
+# Test that GUID specific bits are preserved
+
+# Copyright (C) 2021 SUSE LLC
+
+# This program 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.
+
+# This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.
+
+. "${srcdir=.}/init.sh"; path_prepend_ ../parted $srcdir
+require_512_byte_sector_size_
+
+dev=loop-file
+
+# create device
+truncate --size 50MiB "$dev" || fail=1
+
+# create gpt label and one partitions
+parted --script "$dev" mklabel gpt > out 2>&1 || fail=1
+parted --script "$dev" mkpart "test1" ext4 0% 10% > out 2>&1 || fail=1
+
+# set guid specific bit
+gpt-attrs "$dev" set 0x100000000000000 || fail=1
+
+# create additional partition
+parted --script "$dev" mkpart "test2" ext4 10% 20% > out 2>&1 || fail=1
+
+cat <<EOF > exp || fail=1
+0x100000000000000
+EOF
+
+# check guid specific bit
+gpt-attrs "$dev" show > out || fail=1
+compare exp out || fail=1
+
+Exit $fail