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UEFI GPT

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  UEFI GPT wolfgang kern <nowhere@never.at> - 2024-01-20 05:16 +0100
    Re: UEFI GPT Paul Edwards <mutazilah@gmail.com> - 2024-01-20 23:44 +0800
      Re: UEFI GPT wolfgang kern <nowhere@never.at> - 2024-01-21 00:56 +0100
        Re: UEFI GPT Paul Edwards <mutazilah@gmail.com> - 2024-01-21 10:04 +0800
    Re: UEFI GPT wolfgang kern <nowhere@never.at> - 2024-01-27 09:50 +0100
      Re: Secrets on UEFI GPT wolfgang kern <nowhere@never.at> - 2024-02-09 15:31 +0100
        Re: Secrets on UEFI GPT Herbert Kleebauer <klee@unibwm.de> - 2024-02-09 16:54 +0100
          Re: Secrets on UEFI GPT wolfgang kern <nowhere@never.at> - 2024-02-09 20:08 +0100
            Re: Secrets on UEFI GPT Herbert Kleebauer <klee@unibwm.de> - 2024-02-09 22:03 +0100
              Re: Secrets on UEFI GPT wolfgang kern <nowhere@never.at> - 2024-02-10 05:16 +0100
                Re: Secrets on UEFI GPT wolfgang kern <nowhere@never.at> - 2024-02-10 09:11 +0100
            Re: Secrets on UEFI GPT Paul Edwards <mutazilah@gmail.com> - 2024-02-13 13:57 +0800
              Re: Secrets on UEFI GPT wolfgang kern <nowhere@never.at> - 2024-02-13 08:40 +0100
                Re: Secrets on UEFI GPT wolfgang kern <nowhere@never.at> - 2024-02-13 08:45 +0100
        Re: Secrets on UEFI GPT scott@slp53.sl.home (Scott Lurndal) - 2024-02-09 15:59 +0000
          Re: Secrets on UEFI GPT wolfgang kern <nowhere@never.at> - 2024-02-09 20:12 +0100
            Re: Secrets on UEFI GPT wolfgang kern <nowhere@never.at> - 2024-02-09 20:30 +0100
              Re: Secrets on UEFI GPT scott@slp53.sl.home (Scott Lurndal) - 2024-02-09 20:37 +0000
                Re: Secrets on UEFI GPT wolfgang kern <nowhere@never.at> - 2024-02-10 05:25 +0100
                  Re: Secrets on UEFI GPT cross@spitfire.i.gajendra.net (Dan Cross) - 2024-02-10 19:21 +0000
                    Re: Secrets on UEFI GPT wolfgang kern <nowhere@never.at> - 2024-02-11 02:00 +0100
            Re: Secrets on UEFI GPT scott@slp53.sl.home (Scott Lurndal) - 2024-02-09 20:34 +0000
              Re: Secrets on UEFI GPT wolfgang kern <nowhere@never.at> - 2024-02-10 05:23 +0100
                Re: Secrets on UEFI GPT "Alexei A. Frounze" <alexfrunews@gmail.com> - 2024-02-09 20:45 -0800
                  Re: Secrets on UEFI GPT wolfgang kern <nowhere@never.at> - 2024-02-10 08:59 +0100
                    Re: Secrets on UEFI GPT cross@spitfire.i.gajendra.net (Dan Cross) - 2024-02-11 01:11 +0000
                      Re: Secrets on UEFI GPT wolfgang kern <nowhere@never.at> - 2024-02-11 07:04 +0100
                        Re: Secrets on UEFI GPT cross@spitfire.i.gajendra.net (Dan Cross) - 2024-02-11 20:08 +0000
                          Re: Secrets on UEFI GPT wolfgang kern <nowhere@never.at> - 2024-02-11 22:03 +0100
                          Re: Secrets on UEFI GPT Andy Valencia <vandys@vsta.org> - 2024-02-11 14:38 -0800
                            Re: Secrets on UEFI GPT wolfgang kern <nowhere@never.at> - 2024-02-12 01:48 +0100
        Re: Secrets on UEFI GPT JJ <jj4public@outlook.com> - 2024-02-10 20:10 +0700
          Re: Secrets on UEFI GPT wolfgang kern <nowhere@never.at> - 2024-02-10 17:05 +0100
          Re: Secrets on UEFI GPT wolfgang kern <nowhere@never.at> - 2024-02-14 06:37 +0100

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#18643 — Re: Secrets on UEFI GPT

On 10/02/2024 20:21, Dan Cross wrote:

>>>>>> QUESTIONS still are:  what should I enter into
>>>>>> 1. the 64 bit Disk GUID (also referred as UUID on UNIXes)?

>>> Each one is unique.  It's generated from random data when
>>> each GPT is first created.   It's different in every GPT
>>> (thus every disk on every system in the universe).  It
>>> uniquely identifies the media.

>> I'm totally confused yet,
>> where do these numbers come from and how to get them ?

> They are random numbers.  You make them up, in software, or
> taking from some kind of entropy source.

thx, as already mentioned in this thread I found a source.
but I might just use vendor&serial number of the HD instead.
__
wolfgang

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#18631 — Re: Secrets on UEFI GPT

wolfgang kern <nowhere@never.at> writes:
>On 09/02/2024 16:59, Scott Lurndal wrote:

>> yes.
>
>thanks, do you know a source where I can look up these globally unique?
>or do you know this 16 bytes for FAT32 ?

By definition, every GPT has an unique 16-byte GUID.

Generate and concatenate 2 64-bit true random numbers.

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#18635 — Re: Secrets on UEFI GPT

On 09/02/2024 21:34, Scott Lurndal wrote:
...
>> thanks, do you know a source where I can look up these globally unique?
>> or do you know this 16 bytes for FAT32 ?

> By definition, every GPT has an unique 16-byte GUID.

> Generate and concatenate 2 64-bit true random numbers.

you mean I have to create it ?
how could I make sure it's globally unique then ?
__
wolfgang

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#18637 — Re: Secrets on UEFI GPT

On Friday, February 9, 2024 at 8:23:07 PM UTC-8, wolfgang kern wrote:
> how could I make sure [GUID]'s globally unique then ? 

Probability of collision is expected to be low enough to treat the number unique in practice.
See
https://en.wikipedia.org/wiki/Universally_unique_identifier
and specifically
ITU-T Rec. X.667 or RFC 4122

Alex

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#18638 — Re: Secrets on UEFI GPT

On 10/02/2024 05:45, Alexei A. Frounze wrote:
> On Friday, February 9, 2024 at 8:23:07 PM UTC-8, wolfgang kern wrote:
>> how could I make sure [GUID]'s globally unique then ?
> 
> Probability of collision is expected to be low enough to treat the number unique in practice.
> See
> https://en.wikipedia.org/wiki/Universally_unique_identifier
> and specifically
> ITU-T Rec. X.667 or RFC 4122

thanks a lot Alex, I now can add this link to my GPT-docs

https://www.itu.int/en/ITU-T/asn1/Pages/UUID/uuids.aspx

why was it that hard to get this info :)
__
wolfgang

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#18644 — Re: Secrets on UEFI GPT

In article <uq7ac6$3369l$1@dont-email.me>,
wolfgang kern  <nowhere@never.at> wrote:
>On 10/02/2024 05:45, Alexei A. Frounze wrote:
>> On Friday, February 9, 2024 at 8:23:07 PM UTC-8, wolfgang kern wrote:
>>> how could I make sure [GUID]'s globally unique then ?
>> 
>> Probability of collision is expected to be low enough to treat the number unique in practice.
>> See
>> https://en.wikipedia.org/wiki/Universally_unique_identifier
>> and specifically
>> ITU-T Rec. X.667 or RFC 4122
>
>thanks a lot Alex, I now can add this link to my GPT-docs
>
>https://www.itu.int/en/ITU-T/asn1/Pages/UUID/uuids.aspx
>
>why was it that hard to get this info :)

...it's not?  I mean, did you try to look it up?

	- Dan C.

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#18645 — Re: Secrets on UEFI GPT

On 11/02/2024 02:11, Dan Cross wrote:
> In article <uq7ac6$3369l$1@dont-email.me>,
> wolfgang kern  <nowhere@never.at> wrote:
>> On 10/02/2024 05:45, Alexei A. Frounze wrote:
>>> On Friday, February 9, 2024 at 8:23:07 PM UTC-8, wolfgang kern wrote:
>>>> how could I make sure [GUID]'s globally unique then ?
>>>
>>> Probability of collision is expected to be low enough to treat the number unique in practice.
>>> See
>>> https://en.wikipedia.org/wiki/Universally_unique_identifier
>>> and specifically
>>> ITU-T Rec. X.667 or RFC 4122
>>
>> thanks a lot Alex, I now can add this link to my GPT-docs
>>
>> https://www.itu.int/en/ITU-T/asn1/Pages/UUID/uuids.aspx
>>
>> why was it that hard to get this info :)
> 
> ...it's not?  I mean, did you try to look it up?

of course I did.
I found several hundreds sites who mentioned globally unique ID and only 
two showed a couple of 16 byte values but nothing what I searched for.
And replies except the one from Alex missed to tell that I can download 
a never used new GUID.
__
wolfgang

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#18646 — Re: Secrets on UEFI GPT

In article <uq9o1p$j2ln$1@dont-email.me>,
wolfgang kern  <nowhere@never.at> wrote:
>On 11/02/2024 02:11, Dan Cross wrote:
>> In article <uq7ac6$3369l$1@dont-email.me>,
>> wolfgang kern  <nowhere@never.at> wrote:
>>> On 10/02/2024 05:45, Alexei A. Frounze wrote:
>>>> On Friday, February 9, 2024 at 8:23:07 PM UTC-8, wolfgang kern wrote:
>>>>> how could I make sure [GUID]'s globally unique then ?
>>>>
>>>> Probability of collision is expected to be low enough to treat the number unique in practice.
>>>> See
>>>> https://en.wikipedia.org/wiki/Universally_unique_identifier
>>>> and specifically
>>>> ITU-T Rec. X.667 or RFC 4122
>>>
>>> thanks a lot Alex, I now can add this link to my GPT-docs
>>>
>>> https://www.itu.int/en/ITU-T/asn1/Pages/UUID/uuids.aspx
>>>
>>> why was it that hard to get this info :)
>> 
>> ...it's not?  I mean, did you try to look it up?
>
>of course I did.
>I found several hundreds sites who mentioned globally unique ID and only 
>two showed a couple of 16 byte values but nothing what I searched for.
>And replies except the one from Alex missed to tell that I can download 
>a never used new GUID.

He literally linked you to Wikipedia.  Didn't you search
for "how to generate a UUID"?

	- Dan C.

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#18647 — Re: Secrets on UEFI GPT

On 11/02/2024 21:08, Dan Cross wrote:
[about globally unique]
>>>> why was it that hard to get this info :)
>>>
>>> ...it's not?  I mean, did you try to look it up?
>>
>> of course I did.
>> I found several hundreds sites who mentioned globally unique ID and only
>> two showed a couple of 16 byte values but nothing what I searched for.
>> And replies except the one from Alex missed to tell that I can download
>> a never used new GUID.

> He literally linked you to Wikipedia.
yes, but with useful patterns.

>  Didn't you search for "how to generate a UUID"?
yes, but I found just "random" rather than "unique".
timestamps algorithm are by far not guarantied to be unique.
So I could use my disk's VendorID+SerialNr+date+time, even really unique 
this wouldn't become registered then (WTF who cares?)
__
wolfgang

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#18648 — Re: Secrets on UEFI GPT

wolfgang kern <nowhere@never.at> writes:
> yes, but I found just "random" rather than "unique".
> timestamps algorithm are by far not guarantied to be unique.

And MAC addresses on your LAN interfaces _should_ be unique, except for those
vendors who cheap out and don't invest in a properly managed source of MAC
addresses to assign to their adaptors.

And crypto-hard random numbers _should_ be good enough; get 128 bytes and the
collision odds are small even to the heat death of the universe.  But you
only find out your numbers weren't "random enough" when it's far too late.

Andy Valencia
Home page: https://www.vsta.org/andy/
To contact me: https://www.vsta.org/contact/andy.html

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#18649 — Re: Secrets on UEFI GPT

On 11/02/2024 23:38, Andy Valencia wrote:
> wolfgang kern <nowhere@never.at> writes:
>> yes, but I found just "random" rather than "unique".
>> timestamps algorithm are by far not guarantied to be unique.
> 
> And MAC addresses on your LAN interfaces _should_ be unique, except for those
> vendors who cheap out and don't invest in a properly managed source of MAC
> addresses to assign to their adaptors.
> 
> And crypto-hard random numbers _should_ be good enough; get 128 bytes and the
> collision odds are small even to the heat death of the universe.  But you
> only find out your numbers weren't "random enough" when it's far too late.

128 byte might be good enough, but GPT uses only 16 bytes for GUID.
so the only save way is download from any reliable source.
I may just create whatsoever and hope UEFI doesn't choke on it.
ie: db ASCII(16) "bought on 311223"
__
wolfgang

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#18640 — Re: Secrets on UEFI GPT

On Fri, 9 Feb 2024 15:31:13 +0100, wolfgang kern wrote:
> because nobody responded to my questions and I couldn't find anything on 
> the net it seems some parts of the story are intentional well hidden.
> So now I have to try and fail, which may cost me several month.
> And whenever/if at all I find these missing info I will keep it a secret 
> as well.
> 
> On 27/01/2024 09:50, I wrote:
>> my attempt to manually create a complete UEFI startup with KESYS hexwork
>> still encounter many obstacles :)
>> QUESTIONS still are:  what should I enter into
>> 1. the 64 bit Disk GUID (also referred as UUID on UNIXes)?
>> 2. the 64 bit GUID for FAT32 start partition (first entry in LBA_2)?
>> 3. is it really required to waste 33 sectors for never used entries?
>>     or would my short (only one sector) solution work as well?

Disk and partition IDs (in whatever form they use) are mainly for the upper
level storage drivers to differentiate between them, since they don't
normally deal with storage controller and port numbers (which is a task for
the lower level driver).

Reserved sectors near start of the disk has been around since MBR disk
layout. In MBR, the reserved sector would be up to 62 sectors for disks
which are configured to use 63 sectors per side configuration.

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#18641 — Re: Secrets on UEFI GPT

On 10/02/2024 14:10, JJ wrote:
> On Fri, 9 Feb 2024 15:31:13 +0100, wolfgang kern wrote:
>> because nobody responded to my questions and I couldn't find anything on
>> the net it seems some parts of the story are intentional well hidden.
>> So now I have to try and fail, which may cost me several month.
>> And whenever/if at all I find these missing info I will keep it a secret
>> as well.
>>
>> On 27/01/2024 09:50, I wrote:
>>> my attempt to manually create a complete UEFI startup with KESYS hexwork
>>> still encounter many obstacles :)
>>> QUESTIONS still are:  what should I enter into
>>> 1. the 64 bit Disk GUID (also referred as UUID on UNIXes)?
>>> 2. the 64 bit GUID for FAT32 start partition (first entry in LBA_2)?
>>> 3. is it really required to waste 33 sectors for never used entries?
>>>      or would my short (only one sector) solution work as well?

> Disk and partition IDs (in whatever form they use) are mainly for the upper
> level storage drivers to differentiate between them, since they don't
> normally deal with storage controller and port numbers (which is a task for
> the lower level driver).

Yes I realized that, but I want to manually create an UEFI conform GPT 
start up sector with only four entries (FAT32 as the first).

> Reserved sectors near start of the disk has been around since MBR disk
> layout. In MBR, the reserved sector would be up to 62 sectors for disks
> which are configured to use 63 sectors per side configuration.

well known BS, my OS never wasted any sector. my now old KESYS used code 
in the MBR as first part of the OS core and it continued on LBA_1.
so the whole OS-image (512MB) is stored in consecutive order on disk.

I'll keep this for the new 64bit version even the start may not be on 
LBA_0 due to the UEFI/GPT stuff.
__
wolfgang

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#18655 — Re: Secrets on UEFI GPT

Hi JJ,
I can only read bot not post to CLAX anymore.
please tell Rudy to ask his question again on either ALA or AOD.
I have all answers for him.
__
wolfgang

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