Author Topic: When can I see support for DualBoot ?  (Read 11446 times)

Rajiv

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When can I see support for DualBoot ?
« on: March 27, 2008, 10:05:58 am »
I am waiting for the version which will support Dual Boot (2 independent XP on primary partitions), what is the expected release date.

Thanks.

ntldr

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Re: When can I see support for DualBoot ?
« Reply #1 on: March 27, 2008, 10:10:17 am »
DualBoot without third-party boot manegers are supported in current version.

Rajiv

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Re: When can I see support for DualBoot ?
« Reply #2 on: March 27, 2008, 10:21:42 am »
DualBoot without third-party boot manegers are supported in current version.

I have a laptop with 2 Primary Partitions & 1 Extended Partition with a Logical Drive all the 3 Partitions are formated with NTFS. The 2 Primary Partitions contain WinXP which are independent of each other (One XP cannot see the other when booted as the other Primary Partition is automatically hidden) I use GAG as my bootmanager for this now. Can the current version of diskcryptor help me encrypt my system ? If it can, I would like to know how ?

Thanks
« Last Edit: March 27, 2008, 10:23:13 am by Rajiv »

ntldr

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Re: When can I see support for DualBoot ?
« Reply #3 on: March 27, 2008, 11:48:33 am »
DiskCryptor 0.2.6 not tested with third-party bootmanagers. I not know whether it will work with GAG, please create backups and test it youself.

Rajiv

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Re: When can I see support for DualBoot ?
« Reply #4 on: March 30, 2008, 02:16:06 pm »
DiskCryptor 0.2.6 not tested with third-party bootmanagers. I not know whether it will work with GAG, please create backups and test it youself.

I don't have sufficient HDD Space to completely Image my Laptop's 40 GB HDD so I decided to do a test in VMWare Workstation 5.5.

I made a 6 GB HDD comprising 2 Primary Partitions with 2 GB each and 1 Extended with 2 GB, all formated as NTFS. (My Laptop has 7.2 GB Primary, 2GB Primary, 28 GB Extended)

To test I installed WinXP Pro SP2 on both Primary Partitions and GAG 4.6 as my Boot manager.

In GAG I set the option to boot 1st Primary Partition by default after 5 Seconds as in my Laptop.

I installed DiskCryptor on 1st Primary Partition and Encrypted it.

Then I rebooted the Virtual Machine.

On reboot I was asked for the password, I entered the correct Password and then I got the GAG Screen I Selected the 1st (Encrypted) Partition and it booted successfully.

I rebooted again but this time I gave an incorrect password and then I again got the GAG Screen, I selected the 1st Primary Partition and GAG complained that it could not find the boot sector for it, then I selected the 2nd (Unencrypted) partition and it booted without any problem.

Then I again rebooted the system gave the correct password and in the GAG screen again choose the 1st Partition and voila it booted without any problem (This is where most WDE programmes fail)

I then did random boots to both the partitions and it was working.

Now I want to ask is there anything I must ensure before trying it on my actual Laptop ? I also did not change GAG configuration after using DiskCryptor because I think it will write directly to the boot sector and corrupt DiskCryptor boot loader am I correct ?

What enhancement is expected in 0.3 for dual boot configuration like mine ?

Thanks
« Last Edit: April 04, 2008, 03:48:10 pm by Rajiv »

Rajiv

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Re: When can I see support for DualBoot ?
« Reply #5 on: April 01, 2008, 11:52:30 am »
Can I have a reply please,

Thanks

ntldr

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Re: When can I see support for DualBoot ?
« Reply #6 on: April 01, 2008, 12:36:57 pm »
Now I want to ask is there anything I must ensure before trying it on my actual Laptop ? I also did not change GAG configuration after using Drivecrypt because I think it will write directly to the boot sector and corrupt Drivecrypt boot loader am I correct ?
if GAG gonfigurator write to MBR, you should not change configuration after dc installing.
What enhancement is expected in 0.3 for dual boot configuration like mine ?
In version 0.3 i create bootloaders compatible base, and test dc with various bootloaders
 

Rajiv

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Re: When can I see support for DualBoot ?
« Reply #7 on: April 04, 2008, 03:43:17 pm »
if GAG gonfigurator write to MBR, you should not change configuration after dc installing.

Further testing my VM (from reply no. 4) I changed the configuration of GAG and saved it. However I was surprised when DiskCryptor (Bootloader) was still working flawlessly.

I wanted to know where does DiskCryptor stores its bootloader, and what happens to the data already on the MBR & the first 63 sectors of the HDD (Head No. 1 of HDD) as GAG uses the first 42 sectors of the HDD to store itself and it's configuration.

When I changed the configuration in GAG (It was small like changing default boot time & partition only) it wrote it to the 1st Head of the HDD but still did not corrupt anything. (I even copied the first Head before & after changing the configuration and they were not 100 % identical.

Can you please explain this.

Thanks for the wonderful programmes as well as fast & prompt reply.
« Last Edit: April 04, 2008, 03:49:05 pm by Rajiv »

ntldr

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Re: When can I see support for DualBoot ?
« Reply #8 on: April 04, 2008, 04:08:28 pm »
I wanted to know where does DiskCryptor stores its bootloader
DiskCryptor store bootloader body to hidden cylinder with the end of the disk, and store stage0 boot code to MBR. Old MBR copy saved to bootloader body and executed from it.
If hidden cylinder not present, DiskCryptor store bootloader to first track and boot OS from active partition.

For more details please view dcrypt-0.2.6-src\exe\mbrinst.c, function dc_set_mbr

Rajiv

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Re: When can I see support for DualBoot ?
« Reply #9 on: April 10, 2008, 04:55:57 pm »
After gathering enough courage I made up my mind to try DiskCryptor on my Laptop. I installed DiskCryptor 0.2.6 on my Laptop and then rebooted.

After reboot I started DiskCryptor and selected to encrypt my C: drive (1st Primary Partition of my HDD). It is about 7.3 gb and took approximately 10 min. to fully encrypt. Then I rebooted the system and got the password prompt, I entered the correct password and hit enter, However at this point my system hanged with the message "GAG:3". I believe it was a GAG error.

On further investigation I found that DiskCryptor bootcode has overwritten the first 30 sectors of my HDD and so corrupted the GAG bootcode which uses the first 42 sectors of the HDD. It didn't store its data on any hidden cylinder with the end of the disk.

However from the above experience I am made to believe that if DiskCryptor is able to store its boot code to any other location other than the 1st Head of the HDD it might work with a lot of 3rd party bootloader.

I would like to ask is there any way I can make DiskCryptor write its boot code to the Hidden Cylinder at the end of the disk ? Can it be created if not available ? Is it not possible to shift all the data from 2nd Head of the HDD and put it on the 3rd head of the HDD and Diskcryptor use the 2nd Head to store its configuration.

I would also like to point out one very important shortcoming of the programme. At present it only backs up the 1st sector of the HDD when we install DiskCryptor bootloader. Instead it should store the entire 1st head of the HDD which can then be restored. Since it restores only the MBR, system having 3rd party code on the 1st head will not boot even after decryption and removal of DiskCryptor bootcode.

Waiting for a reply,
Thanks,
Rajiv

Rajiv

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Re: When can I see support for DualBoot ?
« Reply #10 on: April 12, 2008, 11:14:41 am »
Can I have a reply please,

Thanks

...

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Re: When can I see support for DualBoot ?
« Reply #11 on: April 12, 2008, 02:33:25 pm »
At present it only backs up the 1st sector of the HDD .. Instead it should store the entire 1st head of the HDD

I do not agree with that. Only the first sector is specific to your installation, the rest can be restore from installation medias or should be backed up by yourself before the installation.

I found that DiskCryptor bootcode has overwritten the first 30 sectors of my HDD and so corrupted the GAG bootcode
I see another solution: Why has GAG to use exactly these sectors? Can't you copy these sectors into a file and let ntldr use these as chainloader (like with grub or syslinux)?

Look, 1 sector is the MBR, and there is the Partition table. The partition table tells you where the first partiton begins. This could theoretically be the second sector. There is no standard inhibiting this. It is only an unwritten law, that everybody puts the start of the first partiton on the second track. That is, neither DiskCryptor nor GAG not TrueCrypt has the legitimate right to use these sectors, or they document this. As soon as it is documented, then either you can use it like that, or "leave it", or in the case of DiskCryptor, change it yourself. You have the source, so change it to eg to use the second track for the boot code, then GAG can use the first track.
I do not see any reason, why GAG has more rights to use these sectors than DiskCryptor.

Regards
Tom

Rajiv

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Re: When can I see support for DualBoot ?
« Reply #12 on: April 13, 2008, 01:28:07 pm »
I do not agree with that. Only the first sector is specific to your installation, the rest can be restore from installation medias or should be backed up by yourself before the installation.

It is only logical to think that when DiskCryptor is writing some data to a certain part of the HDD, it should be able to restore the same to its original when it is being uninstalled.

However if you continue to think that the end user should be responsible to backup non data areas of the HDD then DiskCryptor should not even backup the MBR, and should leave it to the end user who are often novice and not as knowledgable as yourself.

I see another solution: Why has GAG to use exactly these sectors? Can't you copy these sectors into a file and let ntldr use these as chainloader (like with grub or syslinux)?

Look, 1 sector is the MBR, and there is the Partition table. The partition table tells you where the first partition begins. This could theoretically be the second sector. There is no standard inhibiting this. It is only an unwritten law, that everybody puts the start of the first partition on the second track. That is, neither DiskCryptor nor GAG not TrueCrypt has the legitimate right to use these sectors, or they document this. As soon as it is documented, then either you can use it like that, or "leave it", or in the case of DiskCryptor, change it yourself. You have the source, so change it to eg to use the second track for the boot code, then GAG can use the first track.
I do not see any reason, why GAG has more rights to use these sectors than DiskCryptor.

I am not a programmer nor do I have any experience of working with source codes, or else may be I would have been answering rather than asking questions.

Secondly as far as I know, no other FDE software provides proper DualBoot support, something the developer of DiskCryptor has already indicated would be implementing in DiskCryptor, I was only informing him about my experience on a simple DualBoot system I have. If the author does not want to implement or get feedback regarding this it is his choice.

Thirdly it is not about rights of a certain programme to use certain sectors but about the flexibility of DiskCryptor working on majority of systems with all kinds of different softwares combinations on them.

Regards,
Rajiv

Tom

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Re: When can I see support for DualBoot ?
« Reply #13 on: April 14, 2008, 10:41:07 am »
Hello ntldr

another possibility than using these first sectors (a disadvantage of this approach is the limited space you have) would be to write the bootcode into a (contigous) file in the filesystem. Then
1) the starting sector of this file has to be written into the MBR (like "lilo" does).
2) the file has to be protected against modifications, like defrag. One possibility would be to mark these sectors as badblocks (as badblocks are "ignored" by the filesystem).

Regards
Tom

Rajiv

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Re: When can I see support for DualBoot ?
« Reply #14 on: April 16, 2008, 10:44:36 am »
Hello ntldr,

After my previous experience I started the hunt for a more suitable Boot Manager for my system that can possibly work with DiskCryptor 0.2.6.

I was able to short list 2 possible candidate:-

1. Grub4Dos available at http://sourceforge.net/projects/grub4dos
2. mbldr (Master Boot LoaDeR) available at http://mbldr.sourceforge.net/ is a very small feature rich Boot Loader taking only 446 bytes of MBR space.

I have tested Grub4Dos in my Virtual Machine & it is working properly, and since MBLDR resides within the MBR I see no reason it should not work with DiskCryptor but I have yet to test that.

I would also like to ask if it is possible to integrate a basic boot manager within the bootcode of DiskCryptor particularly like MBLDR as it has the smallest possible footprint and it is open source as well.

Please let me know your thoughts on this,

Best Regards,
Rajiv