0xf4b / f4bctf

Capitalization of CTF stuff

f4bctf

Available commands

Math / Crypto

• RC4 class: RC4("key").crypt("blah")
• discrete_log(): outputs Pari/GP syntax
• discrete_log_ecdh(): outputs Sage syntax
• RSA_padding_oracle(n, e, bits, c0, oracle, verbose=True): RSA PKCS1.5 padding oracle attack

Stego

• stego_wave_lsb(filename, little_endian=True): get lsb from a wave file

Encoding

• base64_encode(a, alphabet="ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/")
• base64_decode(a, alphabet="ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/")

Basic operations

• ror(x, y, size=32)
• rol(x, y, size=32)

Python bytecode manipulation

• py_get_pyc_bytecode(filename): returns a code object from a .pyc file
• py_exec_bytecode(co, bytecode): edit the co_code of a given code object

ELF

• elf_hash(mystr): GNU ELF function name hashing