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-rw-r--r--perl-install/partition_table_gpt.pm174
1 files changed, 174 insertions, 0 deletions
diff --git a/perl-install/partition_table_gpt.pm b/perl-install/partition_table_gpt.pm
new file mode 100644
index 000000000..d908a8103
--- /dev/null
+++ b/perl-install/partition_table_gpt.pm
@@ -0,0 +1,174 @@
+package partition_table_gpt; # $Id$
+
+use diagnostics;
+use strict;
+use vars qw(@ISA);
+
+@ISA = qw(partition_table_raw);
+
+use common;
+use partition_table_raw;
+use partition_table_dos;
+use partition_table;
+use c;
+
+my %gpt_types = (
+ 0x00 => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00",
+ 0x82 => "\x6d\xfd\x57\x06\xab\xa4\xc4\x43\x84\xe5\x09\x33\xc8\x4b\x4f\x4f",
+ 0x83 => "\xA2\xA0\xD0\xEB\xE5\xB9\x33\x44\x87\xC0\x68\xB6\xB7\x26\x99\xC7",
+ 0x8e => "\x79\xd3\xd6\xe6\x07\xf5\xc2\x44\xa2\x3c\x23\x8f\x2a\x3d\xf9\x28",
+ 0xfd => "\x0f\x88\x9d\xa1\xfc\x05\x3b\x4d\xa0\x06\x74\x3f\x0f\x84\x91\x1e",
+ 0xef => "\x28\x73\x2A\xC1\x1F\xF8\xd2\x11\xBA\x4B\x00\xA0\xC9\x3E\xC9\x3B",
+ # legacy_partition_table => "\x41\xEE\x4D\x02\xE7\x33\xd3\x11\x9D\x69\x00\x08\xC7\x81\xF3\x9F"
+ # PARTITION_MSFT_RESERVED_GUID "\x16\xE3\xC9\xE3\x5C\x0B\xB8\x4D\x81\x7D\xF9\x2D\xF0\x02\x15\xAE"
+ #PARTITION_RESERVED_GUID "\x39\x33\xa6\x8d\x07\x00\xc0\x60\xc4\x36\x08\x3a\xc8\x23\x09\x08"
+);
+
+my $current_revision = 0x00010200;
+my ($main_format, $main_fields) = list2kv(
+ a8 => 'magic',
+ V => 'revision',
+ V => 'headerSize',
+ V => 'headerCRC32',
+ a4 => 'blank1',
+ Q => 'myLBA',
+ Q => 'alternateLBA',
+ Q => 'firstUsableLBA',
+ Q => 'lastUsableLBA',
+ a16 => 'guid',
+ Q => 'partitionEntriesLBA',
+ V => 'nbPartitions',
+ V => 'partitionEntrySize',
+ V => 'partitionEntriesCRC32',
+);
+
+my ($partitionEntry_format, $partitionEntry_fields) = list2kv(
+ a16 => 'gpt_type',
+ a16 => 'guid',
+ Q => 'start',
+ Q => 'ending',
+ a8 => 'efi_attributes',
+ a72 => 'name',
+);
+
+$_ = join('', @$_) foreach $main_format, $partitionEntry_format;
+
+my $magic = "EFI PART";
+
+sub crc32 {
+ my ($buffer) = @_;
+
+ my $crc = 0xFFFFFFFF;
+ foreach (unpack "C*", $buffer) {
+ my $subcrc = ($crc ^ $_) & 0xFF;
+ for (my $j = 8; $j > 0; $j--){
+ my $b = $subcrc & 1;
+ $subcrc = ($subcrc >> 1) & 0x7FFFFFFF;
+ $subcrc = $subcrc ^ 0xEDB88320 if $b;
+ }
+ $crc = ($crc >> 8) ^ $subcrc;
+ }
+ $crc;
+}
+
+sub compute_crc {
+ my ($info) = @_;
+ local $info->{headerCRC32} = 0;
+ my $tmp = pack($main_format, @$info{@$main_fields});
+ crc32($tmp) ^ 0xFFFFFFFF;
+}
+
+sub read {
+ my ($hd, $sector) = @_;
+ my $tmp;
+
+ my $l = partition_table_dos::read($hd, $sector);
+ my @l = grep { $_->{size} && $_->{type} && !partition_table::isExtended($_) } @$l;
+ @l == 1 or die "bad PMBR";
+ $l[0]{type} == 0xee or die "bad PMBR";
+ my $myLBA = $l[0]{start};
+
+ local *F; partition_table_raw::openit($hd, *F) or die "failed to open device";
+ c::lseek_sector(fileno(F), $myLBA, 0) or die "reading of partition in sector $sector failed";
+
+ sysread F, $tmp, psizeof($main_format) or die "error while reading partition table in sector $sector";
+ my %info; @info{@$main_fields} = unpack $main_format, $tmp;
+
+ $info{magic} eq $magic or die "bad magic number";
+ $info{myLBA} == $myLBA or die "myLBA is not the same";
+ $info{headerSize} == psizeof($main_format) or die "bad partition table header size";
+ $info{partitionEntrySize} == psizeof($partitionEntry_format) or die "bad partitionEntrySize";
+ $info{revision} <= $current_revision or log::l("oops, this is a new GPT revision ($info{revision} > $current_revision)");
+
+ my $chksum = compute_crc(\%info);
+ $chksum == $info{headerCRC32} or die "bad checksum";
+
+ c::lseek_sector(fileno(F), $info{partitionEntriesLBA}, 0) or die "can't seek to sector partitionEntriesLBA";
+ my %gpt_types_rev = reverse %gpt_types;
+ my @pt = map {
+ sysread F, $tmp, psizeof($partitionEntry_format) or die "error while reading partition table in sector $sector";
+ my %h; @h{@$partitionEntry_fields} = unpack $partitionEntry_format, $tmp;
+ $h{size} = $h{ending} - $h{start};
+ $h{type} = $gpt_types_rev{$h{gpt_type}};
+ $h{type} = 0x100 if !defined $h{type};
+ \%h;
+ } (1 .. $info{nbPartitions});
+
+ [ @pt ], \%info;
+}
+
+# write the partition table (and extended ones)
+# for each entry, it uses fields: start, size, type, active
+sub write {
+ my ($hd, undef, $pt, $info) = @_;
+
+ local *F;
+ partition_table_raw::openit($hd, *F, 2) or die "error opening device $hd->{device} for writing";
+
+ foreach (@$pt) {
+ $_->{ending} = $_->{start} + $_->{size};
+ $_->{gpt_type} = $gpt_types{$_->{type}} || $gpt_types{0x83};
+ }
+
+ $info->{csum} = compute_crc($info);
+
+ c::lseek_sector(fileno(F), $info->{myLBA}, 0) or return 0;
+ #- pad with 0's
+ syswrite F, pack($main_format, @$info{@$main_fields}) . "\0" x 512, 512 or return 0;
+
+ c::lseek_sector(fileno(F), $info->{myLBA}, 0) or return 0;
+
+
+ common::sync();
+ 1;
+}
+
+sub info {
+ my ($hd) = @_;
+
+ #- build a default suitable partition table,
+ #- checksum will be built when writing on disk.
+ my $info = {
+ magic => $magic,
+ revision => $current_revision
+ };
+
+ $info;
+}
+
+sub clear_raw {
+ my ($hd) = @_;
+ my $pt = { raw => [ ({}) x 128 ], info => info($hd) };
+
+ #- handle special case for partition 2 which is whole disk.
+ $pt->{raw}[2] = {
+ type => 5, #- the whole disk type.
+ flags => 0,
+ start_cylinder => 0,
+ size => $hd->{geom}{cylinders} * $hd->cylinder_size(),
+ };
+
+ $pt;
+}
+
+1;