Hedroed / PyCalculator

Simple syntaxe for complexe data transformation

PyCalculator

⚠️ Aborted ⚠️ Simple syntax for complex data transformations.

Requirements

python-prompt-toolkit

Install

python3 setup.py install

Start

pycalc

Prototype

Data conversion

Classic Int to hex with keyword to

>>> 12345 to hex
hex: 3039

Base64 to ascii

>>> ZXhhbXBsZQ== to ascii
Ascii: example

Force type with key word as

>>> "30 39" as hex to int
int: 12345

Automatic recognition

Hexadecimal with 0x prefix

>>> 0x2a
hex: 2a

Binary with 0b prefix

>>> 0x1010
bit: 1010

Base64

>>> ZXhhbXBsZQ==
base64: ZXhhbXBsZQ==

Interger

>>> 12345
int: 12345

Math

>>> 1 + 1
int: 2

Math operation return value of type of the first operand

>>> 0x10 * 0b10
hex: 0x20

Crypto

TODO: Find syntax for the following

• RSA
  • private key generation
  • public key generation
• Hash (MD5, SHA1, SHA256, ...)
• Caesar
  • With key
  • Bruteforce
• ASCII Caesar
  • With key
  • Bruteforce
• XOR
  • With key
  • Known-plaintext attack
  • Xored plaintext attack (cf cryptopals)

Caesar

>>> '57 69 59 5f 5f 55 59 57 5b 69 57 68' as bytes caesar 10 to ascii
ascii: ascii_caesar

Xor bin file with known key

>>> tmp/file.crypt as binFile xor TheSecretKey write /tmp/out as binFile
bytes: \x41\x20\x62\x69\x6e...\x20\x66\x69\x6c\x65

Encoding

TODO: Find syntax for the following

• URL encode / decode
• Double encode
• Base64
• Base32
• Hex

Url encode and decode

>>> urlEncode "' or 1=1 #"
ascii: %27%20or%201%3D1%20%23

>>> urlDecode %27%20or%201%3D1%20%23
ascii: ' or 1=1 #

File

Load data from file

>>> dir/file.txt as textFile
ascii: A text file

And from binary file

>>> dir/file.txt as binFile
bytes: \x41\x20\x62\x69\x6e\x20\x66\x69\x6c\x65

Variable

Save value in variable

>>> 1 + 1 in var1
int: 2 (var1)

Use value from varable

>>> $var1 * 0xa
int: 20

List all varables

>>> $
int: 2 (var1)
bin: 1010 (tmp)
unicode: a string (f)

Types

List of possible data types:

• Int
• Ascii
• Unicode
• Bytes
• Bitarray / Bits
• Hex

• Octal ?
• binFile
• textFile

Modifier

Modifiers affect a single data, it is not an operator

List of modifiers:

• to / .
• as
• in

Operator

List of possible operator:

• +
• -
• /
• *
• xor / ^
• rsa
• `abs'
• factorial / !

Operator like python function but it can take the first parameter at this left. This allow to chain operator

>>> abs -42
int: 42

Factorial

>>> ! 0b101 to int
int: 120

chaining

>>> -4 abs factorial
int: 24

To string operator, not the same as to ascii

>>> 6162 string
ascii: 6162

>>> 6162 to ascii
ascii: ab

Because to will transform value to bytes before convert.

computation order and priority

The interpretor read code from left to right but it is possible to use parenthesis to make action prioritary.

example:

>>> 42 * (a as hex - 8)
int: 84

Escaping space

To escape space it is possible to use the \ escape charactere. Put text in " also escape space.

If you want to escape the first sentence and you have forgot to place a " at the start you can just put a " at the end to the sentence and the interpretor with automatically place a " at the start.

Types definition

Un Type est une class Python qui hérite d'une classe particulière.

Idée de méthodes à redéfinir:

• toString: appelée quand une donnée de ce type est la valeur de retour
• format: appelé par as
• detect: appelé pour détecter automatiquement si un string est de ce type. Si detect retourne True, alors la donnée est de ce type et la méthode format est appelée. (Systeme de priorité)
• toBytes and fromBytes: for default conversion

Un type aura un nom pour le différencier des autres types, par défaut il prendra le nom de sa classe mais il sera possible de le redéfinir.

Il faudrat ajouter ce type aux registres des types connus Exemple:

from pycalclib import registerType, BaseType
import re

class PCInt(BaseType):
    name = 'Int'

    def format(self, value):
        return int(value)

    def detect(self, value):
        return re.test(r'(0|[1-9][0-9]*)', value)  # ex: 12345 (/!\ 01 not work)

    def toString(self, value):
        return value

# Register an Object
registerType(Int())

Operator definition

Un *Operator est une classe Python qui hérite d'une classe particulière.

Une opération doit avoir un type par défaut pour effectuer son calcule. Il sera possible de spécifier un comportement en fonction d'un Type particulier.

Il faudra définir le symbol qui permet de reconnaitre l'operation, il pourrait y en avoir plusieurs (xor et ^)

Exemple:

from pycalclib import registerOperator, BaseOperator

class Addition(BaseOperator):
    default = 'Int'
    symbols = ['+']

    def compute(self, first, second):
        return first + second

    @self.registerOp('Hex')
    def hexOp(self, first, second):
        return first + second

    @self.registerOp('Ascii')
    def asciiConcat(self, first, second):
        return first + second

# Register an Object
registerOperator(Addition())

Stockage des données

Une donnée sera stockée dans un objet Data.

Il contiendra:

• la valeur sous n'importe quelle forme
• le nom du type de cette valeur

Les variable seront stockées dans un dictionnaire avec :

• comme clé le nom de la variable
• comme valeur l'objet Data

Interpretor

Ex: convert int to base64, save in variable and write in text file

>>> 12345678 to base64 in myVar write /tmp/file.txt as textFile
base64: vGFO (myVar)

Cut operation:

• 12345678 to base64:

1. Call detect of all Type and make list of possible Type: Here there is only 'Int'
2. Call format method of Int and save data in Data object as current value
3. Find modifier: is to for conversion
4. Find Type to convert: is base64
5. Find if there is specific method in Int to convert to base64
6. No specific method, so convert Int to default Type: Bytes
7. Call toBytes method of Int
8. Call fromBytes method of base64
9. A data of Type base64 is created

• ... in myVar

1. Find next modifier: is in for variable
2. Get varable name: myVar
3. Save current value in variable dictionnary

• ... write ...

1. Find next operator: is write, is not a modifier
2. compute the Second operand, start after write and stop at the next operator or the end of the line

• /tmp/file.txt as textFile

1. Detect the as modifier
2. Find the Type: is textFile
3. Call format of textFile
4. A data of Type textFile is created

Return at write operator

• ... write ...

1. base64 write in textFile
2. Search for specific method for base64 in write operator: there is not
3. Call compute of write
4. get the return and continue: for write the return is the first operand

• No more operations

1. get the current value
2. call toString
3. print the type name
4. print a column (:)
5. print return of toString

CLI integration (BASH)

Example:

KnownXorAttack.py /tmp/crypt ${pycalc -c "169846466316 to ascii"} > /tmp/file.decrypt