maple3142

from Crypto.Util.number import *

p = getPrime(512)
q = getPrime(512)
e = 65537
n = p * q
dp = inverse_mod(e, p - 1)
m = 1234567894876348763
c = power_mod(m, e, n)

maple3142

from cryptography import x509
from cryptography.hazmat.primitives import hashes, serialization
from cryptography.hazmat.primitives.asymmetric import rsa
from cryptography.x509.oid import (
    NameOID,
    ExtendedKeyUsageOID,
    AuthorityInformationAccessOID,
)

def gen(ocsp_url, ca_url):

maple3142

# Based on https://utaha1228.github.io/ctf-note/2021/11/21/BalsnCTF-2021/
import random
from tqdm import tqdm


class MT19937:
    (w, n, m, r) = (32, 624, 397, 31)
    a = 0x9908B0DF
    (u, d) = (11, 0xFFFFFFFF)
    (s, b) = (7, 0x9D2C5680)

maple3142

from collections import Counter
from math import log
import json
from argparse import ArgumentParser


def get_ctr(txt, n):
    ctr = Counter("".join(x) for x in zip(*[txt[i:] for i in range(n)]))
    return ctr

maple3142

import itertools

# curl -LJO 'https://msolve.lip6.fr/downloads/msolve-v0.2.4.tar.gz'
load("msolve-v0.2.4/interfaces/msolve-to-sage-file-interface.sage")

def msolve_wrap(eqs):
    return MSolveRealRoots(eqs, mspath="msolve-v0.2.4/binary/msolve", p=0)

def all_zz(xs):
    try:

maple3142

Reversing the obfuscated js shows that you can provide payload from query string:

http://cybercook.chal.imaginaryctf.org/?action=base64&input=616263

And the payload will be decoded like this:

s=q.input // q is parsed query string object

maple3142

from tqdm import tqdm

p = 2**255 - 19
m = 314159265358979323846264338327950288419716939937510582097494459230781640628
cf = continued_fraction((m + 87 * p) / (1 + 63 * p))
s = "".join(["-" * x + "/" for x in cf])[:-1]


def calc(m, s):
    for x in s:

maple3142

p1 = 11400714785074694791
p2 = 14029467366897019727
p5 = 2870177450012600261
mask = (1 << 64) - 1


def rol(x, l):
    return ((x << l) | (x >> (64 - l))) & mask

maple3142

N := 16272263761884760913834981570237185012689016739909681724173123311027023698119382194604351367717710439423966215734773732739017169649397007886867641042574372612328200833990505826283627024383229386248616346487228543485039109194654445182620365493334393898275761693877783109565274288153742902157274464598397610141189095624484325167663863550180485641254521697139714498053575172081231983805125962891334660276966188969824322759661626822865129776818152174027045203117029331430920115554670139006395498251713151875940958179247650377893980949189098296912824643766810997471467119541508081507756798709251607976701111186991307217371;
c1 := 1154720460725595432419912121463256063636424922900002916346539904244306803589761923608560394363786646398862561339382783422777269083534736611588855079248972521208730883026494066191103047261851647563891050392249668337425632378542083085965334206476002722020036872618229677291003581600074208003837158590639907087882793309117061515575553888628795766241013386491926120093502009571319539512620135816323

maple3142

#include <memory.h>
#include <stdio.h>
#include <stdlib.h>
#include <algorithm>
#define rotr(val, r) ((val >> r) | ((val & (1L << r) - 1) << (64 - r)))
typedef unsigned long uint64;

void printhex(char *buf, size_t len) {
	for (size_t i = 0; i < len; i++)
		printf("%02hhx", buf[i]);