Improved documentation to reflect sytle information obtained.
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Jeremiah Orians
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README
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README
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@ -1,7 +1,13 @@
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This is a set of manually created hex programs in a Cthulhu Path to madness fashion.
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Which only have the goal of creating a bootstrapping path to a C compiler capable of
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Which only have the goal of creating a bootstrapping path to a C compiler capable of
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Compiling GCC, with only the explicit requirement of a single 1 KByte binary or less.
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Additionally, all code must be able to be understood by 70% of the population of programmers.
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If the code can not be understood by that volume, it needs to be altered until it satifies the above requirement.
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WE DON'T WANT YOUR CLEVER CODE. Only stupidly simple code will be accepted.
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The Madness must be satisfied and only with the Blood ritual of code we perform here.
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This repo contains a few of my false start pieces that may be of interest to people who
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want to independently create the root binary, I welcome all bug fixes and code that aids
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in the above stated goal.
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73
notes.org
73
notes.org
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@ -6,26 +6,31 @@ BE VERY VERY THANKFUL for those that came before us and made such wonderful
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things as assemblers and C compilers that hide most of the horrible darkness from our eyes...
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*** Default memory map
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16-bit mem map (seg:off)
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0x0000:0x0000 -> 0x0000:0x0500 BIOS stuff
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0x0000:0x0500 -> 0x0000:0x2100 root
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0x0000:0x2100 -> 0x0000:0x3300 fat
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0x0000:0x3300 -> 0x0000:0x6c00 14,25kb free space
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0x0000:0x6c00 -> 0x0000:0x7c00 IDT and GDT (256 desc. eatch)
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0x0000:0x7c00 -> 0x0000:0x7e00 bootsector
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0x0000:0x7e00 <- 0x0000:0xffff ~32,5kb stack for boot
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0x1000:0x0000 -> 0x9000:0xffff 576kb free space
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0xa000:0x0000 -> ............. VGA mem etc.
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| 16-bit mem map (seg:off) | What is there |
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|--------------------------------+-------------------------------|
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| 0x0000:0x0000 -> 0x0000:0x0500 | BIOS stuff |
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| 0x0000:0x0500 -> 0x0000:0x2100 | root |
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| 0x0000:0x2100 -> 0x0000:0x3300 | fat |
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| 0x0000:0x3300 -> 0x0000:0x6c00 | 14,25kb free space |
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| 0x0000:0x6c00 -> 0x0000:0x7c00 | IDT and GDT (256 desc. eatch) |
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| 0x0000:0x7c00 -> 0x0000:0x7e00 | bootsector |
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| 0x0000:0x7e00 <- 0x0000:0xffff | ~32,5kb stack for boot |
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| 0x1000:0x0000 -> 0x9000:0xffff | 576kb free space |
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| 0xa000:0x0000 -> ............. | VGA mem etc. |
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*** Restart code
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To restart the segment loaded from the bootsector:
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68007C ; push 7C00
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C3 ; ret
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| Hex | Assembly Equivelent |
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|--------+---------------------|
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| 68007C | push 7C00 |
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| C3 | ret |
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For an intersegment restart:
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6A00 ; push 0
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68007C ; push 7C00
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CF ; iret
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| Hex | Assembly Equivelent |
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|--------+---------------------|
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| 6A00 | push 0 |
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| 68007C | push 7C00 |
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| CF | iret |
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* Testing notes
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** Making blank floppy disk images
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@ -45,49 +50,65 @@ change floppy0 blank_floppy.img
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** Building binaries for testing
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*** stage0_monitor
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There are literally hundreds of ways of building the root bootstrap binary.
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All that is required is a simply hex compiler written in any language on
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any system available to the user.
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This repository contains a hex compiler written for Linux in hex and assembly as
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well as a platform independent C implementation.
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Then to complete the build process write to the master boot record of a floppy disk.
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Or should you desire simply use qemu to boot the compiled file directly.
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* Creation journal
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** Linux bootstrap
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The initial prototyping was done on linux with the goal of not
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requiring anything other than the linux kernel.
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However it was pointed out to me that should a trusting trust attack be in the compiled kernel,
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there would be no way to even trust the binaries produced by these programs.
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The initial prototyping was done on linux with the goal of not requiring anything other than the linux kernel.
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However it was pointed out to me that should a trusting trust attack be in the compiled kernel, there would be no way to even trust the binaries produced by these programs.
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That being said they may be of some use to you.
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** Stage 0
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Lacking a good basis for reducing the trusting trust attack, it was decided to reduce the scope down.
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By writing the stage 0 code in commented hex, it becomes possible for universal cross compilation and verification.
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The only real problem is that the commented hex has to be manually validated [An insanely painful process] and
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each and every single platform has to perform the exact same tasks.
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The only real problem is that the commented hex has to be manually validated [An insanely painful process] and each and every single platform has to perform the exact same tasks.
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Since all such projects have to start somewhere, I have choosen to do it myself and with the 8088.
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To make my work easier, I first created the working code in 16bit assembly. Then after testing is validated,
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I begin the pain staking process of manually converting the code to hex [With usually a dozen bugs along the way].
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To make my work easier, I first created the working code in 16bit assembly.
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Then after testing is validated, I begin the pain staking process of manually converting the code to hex [With usually a dozen bugs along the way].
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What I however require is someone with a completely alien platform verify the compiled hex for the stage0_monitor.
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Which has the following checksum values:
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md5: 9e29544f0220636437741cb5092cc411
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sha1: b26c72762d2f77d8634cb532d581c1e76adceb3f
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sha256: 045ef96e1c8fb011cba89f268f823c06b21f91270fb9afb0af42a1ac8c3ee44b
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| Name | Value |
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|--------+------------------------------------------------------------------|
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| md5 | 9e29544f0220636437741cb5092cc411 |
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| sha1 | b26c72762d2f77d8634cb532d581c1e76adceb3f |
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| sha256 | 045ef96e1c8fb011cba89f268f823c06b21f91270fb9afb0af42a1ac8c3ee44b |
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If your compiled hex is different in any way, please let me know as the process should produce bit idential binaries.
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** Stage 1
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Stage 1 attempts to save myself from alot of manual typing and the inevitable errors that occur.
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It simply provides the functionality required to produce 32KB or smaller binaries from Commented Hex files.
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This is a minor stopping point of functionality that provides a stable nub for our much more ambitious stages that come later.
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The editors lack the ability to correct mistakes and always writes a 64KB file onto the B: floppy.
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The loader is so stupid is only loads 64KB from the A: Floppy and doesn't even prompt the user.
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However despite those stupid limitations, they have saved alot of manual work compared to stage0.
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Having these binaries are a huge step forward compared to not having them but they assume you don't make mistakes.
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** Stage 2
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Stage 2 will be introducing enhancements to Stage 1 programs that allow you to fix the problems you accidentially introduce.
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We will also begin to introduce programs that make software development alot easier.
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