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Hack the planet!

David Buchanan DavidBuchanan314

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Hack the planet!
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DavidBuchanan314 / vxworks_help.txt
Created March 10, 2025 17:45
No ethernet available
Adding Xtra Brick Ram @0xa000000, Size = 6291264 - 12 cards.
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DavidBuchanan314 / very_equal.py
Created January 20, 2025 14:52
import unsafe # https://github.com/DavidBuchanan314/unsafe-python
mem = unsafe.getmem()
def very_equal(a: int, b: int) -> None:
addr = id(a)
mem[addr+24:addr+32] = b.to_bytes(8, "little")
very_equal(2 + 2, 5)
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DavidBuchanan314 / demo.py
Last active December 6, 2024 18:21
magically import magic number constants (edit: moved to github https://github.com/DavidBuchanan314/magic-numbers (and pypi(!)))
from magic_numbers import FORTY_TWO, SIXTY_NINE, FOUR_HUNDRED_AND_TWENTY
from magic_numbers import ONE_THOUSAND_THREE_HUNDRED_AND_TWELVE
print(f"{FORTY_TWO = }")
print(f"{SIXTY_NINE = }")
print(f"{FOUR_HUNDRED_AND_TWENTY = }")
print(f"{ONE_THOUSAND_THREE_HUNDRED_AND_TWELVE = }")
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DavidBuchanan314 / phc_string.py
Created December 3, 2024 06:54
# https://github.com/P-H-C/phc-string-format/blob/master/phc-sf-spec.md
import re
import base64
PHC_STRING_RE = re.compile(r"""
\$(?P<id>[a-z0-9-]{1,32})
(\$v=(?P<version>[0-9]+))?
(\$(?P<params>[a-z0-9-]{1,32}=[a-zA-Z0-9/+.-=,]*))? # NOTE: full param parse happens later, this just checks at least one param exists
(
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DavidBuchanan314 / indentless_exceptions.py
Last active December 1, 2024 06:50
[
(try_except := (lambda fn, exception_callback:
type("mycontext", (__import__("contextlib").ContextDecorator,), {
"__enter__": lambda self: self,
"__exit__": lambda self, a, b, c: (a and exception_callback(a, b, c)) or True
})()(fn)()
)),
(throw := lambda e:
(_ for _ in ()).throw(e)
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DavidBuchanan314 / aoc_2024_01.py
Last active December 1, 2024 06:50
(
solve := lambda data: sum(
abs(a - b) for a, b in
zip(*map(sorted,zip(*(
map(int, line.split())
for line in data.split("\n")
))))
),
example := """\
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DavidBuchanan314 / arch-chroot-kindle.sh
Created November 23, 2024 19:24
arch-chroot from the arch-install-scripts package, hacked up to work from a kindle
#!/bin/bash
# SPDX-License-Identifier: GPL-2.0-only
shopt -s extglob
unshare=0
keepresolvconf=0
#!/hint/bash
# SPDX-License-Identifier: GPL-2.0-only
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DavidBuchanan314 / merkle_search_trees.md
Last active January 15, 2025 17:49
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DavidBuchanan314 / notes.md
Last active April 15, 2025 14:01
JNIC Reversing Notes https://jnic.dev/

I looked at a JAR file protected using JNIC, version jnic.dev v3.6.0. I haven't written a full-auto deobfuscater yet, but these notes should be useful for anyone reversing it.

The first layer is a LZMA2 compressed .dat file, from which a native library is extracted into a temp dir, and then loaded using System.load.

The sample I looked at had 4 different library versions (for different platforms/architectures), and the script I wrote to extract them looks like this:

import lzma

# from JNICLoader.java
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DavidBuchanan314 / mtk_geniezone_decrypt.py
Created July 7, 2024 18:01
from cryptography.hazmat.primitives.ciphers import Cipher, algorithms, modes
KEY = bytes.fromhex("5c0e349a27dc46034c7b6744a378bd17")
IV = bytes.fromhex("a0b0924686447109f2d51dcddc93458a")
img = open("gz_a.bin", "rb")
img.seek(4)
length = int.from_bytes(img.read(4), "little")
img.seek(0x34)
offset = int.from_bytes(img.read(4), "little")