Attachment 48582 Details for Bug 114429

script with lilo mbr

tp_mbr (text/plain), 3.49 KB, created by Steffen Winterfeldt on 2005-09-02 11:08:13 UTC

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Creator: Steffen Winterfeldt

Created: 2005-09-02 11:08:13 UTC

Size: 3.49 KB

patch

obsolete

>#! /usr/bin/perl
>
>#
># Install MBR on Thinkpads.
>#
># TPs have a special boot loader to manage the rescue stuff. It keeps the
># orignal MBR stored somewhere and uses it to boot the normal OSes.
>#
># MBR[6]: 1 byte CRC over original MBR
># MBR[7]: sector number of original MBR
>#
>
>sub crc;
>
># lilo mbr
>$new_mbr =
>  "\xfa\xeb\x31\x12\x00\x00\x4c\x49\x4c\x4f\x16\x07\x10\x00\x01\x00" .
>  "\x00\x7c\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x5e\xac\x08\xc0" .
>  "\x74\x09\xb4\x0e\xbb\x07\x00\xcd\x10\xeb\xf2\xb9\x13\x00\xb4\x86" .
>  "\xcd\x15\xcd\x18\x31\xc0\x8e\xd0\xbc\x00\x7c\xfb\x89\xe1\x06\x53" .
>  "\x56\x52\x89\xce\xfc\x8e\xd8\x8e\xc0\xbf\x00\x06\xb9\x00\x01\xf3" .
>  "\xa5\xea\x56\x06\x00\x00\x60\xb8\x00\x12\xb3\x36\xcd\x10\x61\x66" .
>  "\x8b\x3e\xb8\x07\x66\x09\xff\x74\x1b\xb4\x08\xb2\x80\xcd\x13\x0f" .
>  "\xb6\xca\x92\xba\x80\x00\xe8\x9a\x00\x66\x3b\x3e\xb8\x7d\x74\x04" .
>  "\x42\xe2\xf3\x92\xbe\xbe\x07\xb9\x04\x00\xf6\x04\x80\x89\xf5\x78" .
>  "\x33\x83\xc6\x10\xe2\xf4\xe8\x83\xff\x4e\x6f\x20\x70\x61\x72\x74" .
>  "\x69\x74\x69\x6f\x6e\x20\x61\x63\x74\x69\x76\x65\x0d\x0a\x00\xf6" .
>  "\x04\x80\x79\x10\xe8\x65\xff\x49\x6e\x76\x61\x6c\x69\x64\x20\x50" .
>  "\x54\x0d\x0a\x00\x83\xc6\x10\xe2\xe6\x89\xee\x66\x8b\x44\x08\x66" .
>  "\xa3\x14\x06\xe8\x3d\x00\x81\x3e\xfe\x7d\x55\xaa\x75\x11\x31\xc0" .
>  "\x58\x3c\xfe\x75\x06\x88\xd4\x5e\x5b\x07\x92\xff\x2e\x10\x06\xe8" .
>  "\x2a\xff\x4e\x6f\x20\x62\x6f\x6f\x74\x20\x73\x69\x67\x6e\x61\x74" .
>  "\x75\x72\x65\x20\x69\x6e\x20\x70\x61\x72\x74\x69\x74\x69\x6f\x6e" .
>  "\x0d\x0a\x00\x60\xbd\x0c\x00\xbe\x0c\x06\xbb\xaa\x55\xb4\x41\xcd" .
>  "\x13\x72\x0f\x81\xfb\x55\xaa\x75\x09\xf6\xc1\x01\x74\x04\xb4\x42" .
>  "\xeb\x3f\x52\xb4\x08\xcd\x13\x72\x43\x51\xc0\xe9\x06\x86\xe9\x89" .
>  "\xcf\x59\xc1\xea\x08\x92\x40\x83\xe1\x3f\xf7\xe1\x93\xa1\x14\x06" .
>  "\x8b\x16\x16\x06\x39\xda\x73\x22\xf7\xf3\x39\xf8\x77\x1c\xc0\xe4" .
>  "\x06\x86\xe0\x92\xf6\xf1\x08\xe2\x89\xd1\x41\x5a\x88\xc6\xb8\x01" .
>  "\x02\xc4\x5c\x04\xcd\x13\x72\x05\x61\xc3\xb4\x40\x5a\x4d\x74\x06" .
>  "\x30\xe4\xcd\x13\xeb\x91\xe8\x93\xfe\x44\x69\x73\x6b\x20\x72\x65" .
>  "\x61\x64\x20\x65\x72\x72\x6f\x72\x0d\x0a\x00\x00\x00\x00\x00\x00" .
>  "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" .
>  "\x00\x00\x00\x00\x00\x00\x00\x00\xcd\xcc\xcd\xcc\x00\x00";
>
>
>$disk = shift;
>
>die "usage: tp_mbr device\n" unless $disk && (-f($disk) || -b($disk));
>
>open F, $disk;
>sysread F, $mbr, 0x200;
>
>@mbr = unpack "C512", $mbr;
>
>die "$disk: no mbr\n" unless @mbr == 0x200 && $mbr[0x1fe] == 0x55 && $mbr[0x1ff] == 0xaa;
>
>$old_mbr_sec = $mbr[7];
>
># just a quick check
>die "$disk: np tp mbr\n" unless
>  $mbr[0x17b] == 0x50 &&
>  $mbr[0x17c] == 0xe4 &&
>  $mbr[0x17d] == 0x61 &&
>  $mbr[0x17e] == 0x24 &&
>  $old_mbr_sec > 1;
>
>
># read original mbr
>
>seek F, ($old_mbr_sec - 1) << 9, 0 or die "$disk: $!\n";
>
>sysread F, $old_mbr, 0x200;
>
>@old_mbr = unpack "C512", $old_mbr;
>
>die "$disk: no orig mbr\n" unless @old_mbr == 0x200 && $old_mbr[0x1fe] == 0x55 && $mbr[0x1ff] == 0xaa;
>
>close F;
>
>
># verify crc
>
>if($mbr[6] == 0) {
>  print STDERR "$disk: orig mbr crc not checked\n" if $mbr[6] == 0;
>}
>else {
>  die "$disk: orig mbr crc failure\n" unless crc(\@old_mbr) == $mbr[6];
>}
>
>
># store new mbr & update crc
>
>substr($old_mbr, 0, length $new_mbr) = $new_mbr;
>
>@old_mbr = unpack "C512", $old_mbr;
>
>$mbr[6] = crc \@old_mbr;
>
>$mbr = pack "C512", @mbr;
>
>
># write it
>
>open F, "+<$disk";
>syswrite F, $mbr, 0x200;
>seek F, ($old_mbr_sec - 1) << 9, 0;
>syswrite F, $old_mbr;
>close F;
>
>
># crc function
>sub crc
>{
>  my $c = 0;
>  local $_;
>
>  $c ^= $_ for @{$_[0]};
>
>  return $c;
>}
>

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Attachments on bug 114429: 48386 | 48506 | 48582 | 48596