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Basic conversions

int to bytes, byte to int

from Crypto.Util.number import *

a = b"blahblah"
b = bytes_to_long(a)
c = long_to_bytes(b)

bytes to hex, hex to bytes

from Crypto.Util.number import *

a = "deadbeef"
b = bytes.fromhex(a)
c = hex(bytes_to_long(b))

base64, 58 whatever

import base64

a = "d293IHUgZGVjb2RlZCB0aGlzLiBjcmF6eS4gdXIgc28gdGFsZW50ZWQuIHNvIHNtYXJ0IA=="
b = base64.b64decode(a).decode()
c = base64.b58decode(a).decode()

individual byte list to bytestring ?

a = [101, 234, 255, 10, 11, 12]
b = bytearray(a)

Basic factoring

factordb

goated.
alternatively visit the site. but scripting encouraged.
use pip install factordb-pycli for the module.

from factordb.factordb import FactorDB

N = # number to be factored
f = FactorDB(N)
f.connect()
primes = f.get_factor_list()

sympy

less goated. Use for smaller numbers ig.

from sympy import *

N = # number to be factored
factors = factorint(N).keys()

ALPERTRON

other algorithms for factoring may include :

  • lenstras ecm
  • pollard's p-1
  • Quadratic Sieve
    // to be implemented and logged

solving a set of equations

sympy

from sympy import *  # pip install sympy

x,y,z = symbols('x y z')
eq1 = Eq( # LHS, # RHS )
eq2 = Eq( # LHS, # RHS )
eq3 = Eq( # LHS, # RHS )

# for n unknowns, n equations only.

z3

from z3 import *   # pip install z3-solver

solver = Solver()
x = Int('x')
y = Int('y')
z = Int('z')

solver.add( # first equation in the form : LHS == RHS )
solver.add( # second equation in the form : LHS == RHS )
solver.add( # third equation in the form : LHS == RHS )

# can also add conditions in z3 such that :
solver.add( x > y )
solver.add( y > z )

learn z3 -> https://github.com/ViRb3/z3-python-ctf

cheating basically

cyber chef - https://gchq.github.io/CyberChef/
dcode - https://www.dcode.fr/en
enigma - https://cryptii.com/pipes/enigma-machine
morse - https://morsecode.world/international/translator.html
citrix ctx1 - https://asecuritysite.com/cipher/citrix