Chain booting Linux from Windows using Darwin chain0

EasyBCD can create a Windows boot menu entry for Linux, using GRUB installed in its partition. This copies the boot sector of the selected partition to C:\NST\nst_linux.mbr and sets up an entry to boot via that file. This works, but it can stop working if upgrades are installed in Linux and the boot sector changes. In that case, the boot sector needs to be copied to that file again. Deleting and re-creating the menu entry in EasyBCD will accomplish that.

It would be better to read the boot sector directly, but I don't think Windows supports that. Another alternative is to use a boot sector file which finds and loads the real boot sector. This approach is used when loading Mac OS X or Darwin via chain0. You can obtain a version of chain0 at C:\NST\nst_mac.mbr by setting up a Mac OS X MBR boot entry in EasyBCD. The version I have has an MD5 value of cfca64f400ef99e89b51e59bcb697137. I patched it to search for the Linux partition instead of OS X and used that version as nst_linux.mbr:

C:\NST>fc /b nst_mac.mbr nst_linux.mbr
Comparing files nst_mac.mbr and NST_LINUX.MBR
0000008A: AB 83
00000090: A8 83
00000096: AF 83

It can search for three different partition types, but I only need to search for one so I set them all to 83 hex. This can successfully boot Linux from the first partition in my extended partition. If you have a more complicated setup, you may need a different version of chain0 with a fix for accessing other partitions in the extended partition.

Download the modified chain0 here.