from ecdsa import SigningKey, NIST521p
from hashlib import sha512
from Crypto.Util.number import long_to_bytes
import random
import binascii
import sys
digest_int = int.from_bytes(sha512(b"Welcome to this challenge!").digest(), "big")
curve_order = NIST521p.order
priv_int = digest_int % curve_order
priv_bytes = long_to_bytes(priv_int, 66)
sk = SigningKey.from_string(priv_bytes, curve=NIST521p)
vk = sk.verifying_key
f_pub = open("public.pem", "wb")
f_pub.write(vk.to_pem())
f_pub.close()

msgs = [b"message-" + bytes([i]) for i in range(60)]
sigs = []
def nonce(i):
    seed = sha512(b"bias" + bytes([i])).digest()
    k = int.from_bytes(seed, "big")
    return k

for i, msg in enumerate(msgs):
    k = nonce(i)
    sig = sk.sign(msg, k=k)
    sigs.append((binascii.hexlify(msg).decode(), binascii.hexlify(sig).decode()))

f_sig = open("signatures.txt", "w")
for m, s in sigs:
    f_sig.write("%s:%s\n" % (m, s))
f_sig.close()

from hashlib import sha512, md5

msg = b"Welcome to this challenge!"
digest = sha512(msg).digest()
priv_int = int.from_bytes(digest, "big")
flag_md5 = md5(str(priv_int).encode()).hexdigest()
print(f"flag{{{flag_md5}}}")

# f() 函数验证脚本 
a1 = 100
v5 = 0
v4 = 1
for i in range(a1):
    v2 = v4
    v4 = (v5 + v4) & 0xF
    v5 = v2
    print(v5, end=' ')

import base64
import zlib

__ = '=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'
while True:
    try:
        b = base64.b64decode(__[::-1])
        e = zlib.decompress(b).decode()
        s = e.split("'")
        __ = s[1]
    except:
        print("'".join(s))
        break

import pandas as pd
import numpy as np
import socket
import time

def solve():
    df = pd.read_csv('misc\public_ledger.csv')
    df.columns = [f'feat_{i}' for i in range(20)]
    means = df.mean()
    cov_matrix = df.cov()

    shrink_factor = 0.2
    num_to_generate = 7000
    
    samples = np.random.multivariate_normal(means, cov_matrix * shrink_factor, num_to_generate)

    dist = np.linalg.norm(samples - means.values, axis=1)
    safe_indices = np.argsort(dist)[:6200]
    final_samples = samples[safe_indices]
    
    fake_df = pd.DataFrame(final_samples, columns=df.columns)
    fake_df[fake_df < 0] = 0

    payload = fake_df.to_csv(index=False) + "\nEOF\n"

    host = "39.105.197.135"
    port = 22541
    
    try:
        with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s:
            s.settimeout(60)
            print(f"连接 {host}:{port}...")
            s.connect((host, port))
            
            time.sleep(1)
            try:
                print(s.recv(1024).decode(errors='ignore'))
            except:
                pass
            s.sendall(payload.encode())
            
            response = ""
            while True:
                chunk = s.recv(4096).decode(errors='ignore')
                if not chunk: break
                response += chunk
                print(chunk, end="", flush=True)
                if "flag{" in response.lower():
                    print("\n获取 Flag")
                    break
                if "ALARM" in response:
                    print("\n错误")
                    break
    except Exception as e:
        print(f"\n[!] 连接异常: {e}")

if __name__ == "__main__":
    solve()

from Crypto.Cipher import AES
import base64
# from FLAG  import flag

def pkcs7_pad(data):
    block = 16
    padding_len = block - len(data) % block
    return data + bytes([padding_len]) * padding_len

key_l3 = [65, 65, 65]

def main():
    while key_l3[0] != 0x7e:
        key_l3[2] += 1
        if (key_l3[2] > 0x7e):
            key_l3[2] = 65
            key_l3[1] += 1
        if (key_l3[1] > 0x7e):
            key_l3[1] = 65
            key_l3[0] += 1
        key = "ZJTIE-CTF-IS-" + chr(key_l3[0]) + chr(key_l3[1]) + chr(key_l3[2])
        print(key)
        cipher = AES.new(key.encode(), AES.MODE_ECB)
        encode_text = base64.b64decode('patCICFf4hK+vmHQaDhaqn+j+/dHGsfkoky0TUDjSsVOe/PQcEgznf9F65BgH5Ek')
        try:
            plain_text = cipher.decrypt(encode_text).decode()

            print(plain_text)
            break
        except:
            continue
if __name__ == "__main__":
    main()

text = b'ZKVJA~6e::?;;9#9qw\"> $$$5!x)(0*-FG\x17'
_hex = 0x571C4B11101D4246
b = _hex.to_bytes(8, byteorder='little')
text += b

for i in range(len(text)):
    print(chr(text[i] ^ i), end='')
print()

import libnum
sum = 15870713655456272818998868095126610389501417235762009793315127525027164306871912572802442396878309282140184445917718237547340279497682840149930939938364752
dif = 836877201325346306269647062252443025692393860257609240213263622058769344319275021861627524327674665653956022396760961371531780934904914806513684926008590
p = (sum + dif) // 2
q = sum - p
n = p * q
phi_n = (q - 1) * (p - 1)
e = 65537
c = 24161337439375469726924397660125738582989340535865292626109110404205047138648291988394300469831314677804449487707306159537988907383165388647811395995713768215918986950780552907040433887058197369446944754008620731946047814491450890197003594397567524722975778515304899628035385825818809556412246258855782770070

d = pow(e, -1, phi_n)

m = pow(c, d, n)

flag = libnum.n2s(m)
flag = flag.decode('utf-8')
print(flag)

import base64
from Crypto.Cipher import AES
from Crypto.Util.Padding import unpad
import hashlib

def decrypt_aes_cbc(ciphertext_b64, password, iv):
    key = hashlib.md5(password.encode()).digest()[:16]

    cipher = AES.new(key, AES.MODE_CBC, iv.encode())

    ciphertext = base64.b64decode(ciphertext_b64)

    plaintext_padded = cipher.decrypt(ciphertext)
    plaintext = unpad(plaintext_padded, AES.block_size)

    return plaintext.decode('utf-8')

if __name__ == "__main__":
    ciphertext = "H4vkfGfsU+qBEwaa7ea9gBkRcraMqbe4BGaxDb/9JG4zGleqT1VxyzGbDj/yuQn8"
    password = "Cryptography"
    iv = "0123456789abcdef"

    plain = decrypt_aes_cbc(ciphertext, password, iv)
    print(plain)

import base64

a = list(base64.b32decode('NBWX633YNJLU2QSILZBUKSDTJVBFQRLTJVBEQ42YJFPVQ42FL5ZUKQSYJFPESX2YIVBEWUI='))

for i in a:
    print(chr(i ^ 44), end='')

external = '26c39cf8-55fb-4899-82bc-442cf4627d95.jpg+6e17fffa-b696-4769-9b43-e0f453f8098d.jpg+7a19da17-9f4a-411b-bac7-83d2454d868a.jpg+897a3a87-dfcf-4233-8097-6bba2e6507ba.jpg+c6b1099a-d626-4cbd-94fc-32aa46ffb02b.jpg+d5117480-7943-48f8-9e79-67fdd51092d2.jpg'

import hashlib

# 创建md5对象
md5_obj = hashlib.md5()
md5_obj.update(external.encode())
print(md5_obj.hexdigest())

def id_check(id):
    if len(id) != 18: return False
    if id[-1].upper() == 'X':
        if not id[:-1].isdigit(): return False
    else:
        if not id.isdigit(): return False
    if id_verify(id) != id[-1].upper(): return False
    return True

def id_verify(id):
    c = [7, 9, 10, 5, 8, 4, 2, 1, 6, 3, 7, 9, 10, 5, 8, 4, 2]
    b = [int(id[i]) * c[i] for i in range(17)]
    a = sum(b) % 11
    m = ['1', '0', 'X', '9', '8', '7', '6', '5', '4', '3', '2']
    return m[a]

def sex_verify(id, sex):
    sex_id = id[-2]
    if int(sex_id) % 2 == 0:
        return sex == '女'
    else:
        return sex == '男'

def birth_check(id, birthday):
    id_birth_year = id[6:10]
    id_birth_month = id[10:12]
    id_birth_day = id[12:14]
    birthday_from_info = birthday.split('-')
    return int(id_birth_year) == int(birthday_from_info[0]) and int(id_birth_month) == int(birthday_from_info[1]) and int(id_birth_day) == int(birthday_from_info[2])

def mobile_check(mobile):
    if len(mobile) != 11: return False
    if not mobile.startswith('1'): return False
    if not mobile.isdigit(): return False
    return True

from datetime import datetime
def time_logic_check(birthday, register, last_login):
    birth_date = datetime.strptime(birthday, '%Y-%m-%d')
    register_date = datetime.strptime(register, '%Y-%m-%d %H:%M:%S')
    last_login_date = datetime.strptime(last_login, '%Y-%m-%d %H:%M:%S')
    return (birth_date < register_date) and (register_date <= last_login_date)

def name_check(name):
    if len(name) < 2 or len(name) > 4: return False
    if not name.isalpha(): return False
    return True

import csv

info_legal = []
with open('data.csv', 'r', encoding='utf-8') as file:
    reader = csv.reader(file)
    for row in reader:
        # 1.身份证号格式验证
        if not id_check(row[2]):
            continue
        if not id_verify(row[2]):
            continue
        # 2.性别一致性验证
        if not sex_verify(row[2], row[3]):
            continue
        # 3.出生日期一致性验证
        if not birth_check(row[2], row[5]):
            continue
        # 4.手机号格式验证
        if not mobile_check(row[4]):
            continue
        if not time_logic_check(row[5], row[6], row[7]):
            continue
        # 6.姓名格式验证
        if not name_check(row[1]):
            continue
        info_legal.append(row)

with open('legals.csv', 'w', encoding='utf-8', newline='') as file:
    writer = csv.writer(file)
    writer.writerow(['客户ID','姓名','身份证号','性别','手机号','出生日期','注册时间','最后登录时间'])
    for row in info_legal:
        writer.writerow(row)

balance_error = []
bank_error = []
frequent_error = []

price_area = {
    '电子产品': [100, 5000],
    '服装鞋包': [50, 1000],
    '家居用品': [30, 2000],
    '美妆护肤': [20, 800],
    '食品饮料': [5, 300],
    '图书文具': [5, 200],
    '运动户外': [50, 3000]
}
def balance_check(goods_type, price):
    return not (float(price) < price_area[goods_type][0] or float(price) > price_area[goods_type][1])

def bank_check(bank):
    if len(bank) < 16 or len(bank) > 19 or not bank.isdigit(): return False
    s = 0
    for i in range(len(bank) - 1, -1, -1):
        t = int(bank[i])
        if (len(bank) - i) % 2 == 0:
            t = t * 2
        t = t % 9
        s += t
    return (s % 10 == 0)


usage_analyze = {
    '': {
        '0000000000000000': []
    }
}
def usage_check(row):
    order_hour = row[3].split(':')[0]
    if usage_analyze.get(order_hour) == None:
        usage_analyze.update({order_hour: dict()})
    if usage_analyze[order_hour].get(row[6]) == None: # row[6] = 银行卡号
        usage_analyze[order_hour].update({row[6]: list()})
    usage_analyze[order_hour][row[6]].append(row[1])

order_analyze = {
}
def order_check(row):
    order_hour = row[3].split(':')[0]
    if order_analyze.get(order_hour) == None:
        order_analyze.update({order_hour: dict()})
    if order_analyze[order_hour].get(row[1]) == None: # row[1] = 用户ID
        order_analyze[order_hour].update({row[1]: 0})
    order_analyze[order_hour][row[1]] += 1

import csv
from datetime import datetime
with open('data.csv', 'r', encoding='utf-8') as file:
    reader = csv.reader(file)
    for row in reader:
        # 1.金额异常检测
        if not balance_check(row[4], row[2]):
            balance_error.append(row[1])
        # 2.银行卡异常检测
        if not bank_check(row[6]):
            bank_error.append(row[1])
        # 2.3使用异常检测
        usage_check(row)
        # 3.频率异常检测
        order_check(row)

for hour in usage_analyze.keys():
    for card in usage_analyze[hour].keys():
        if len(usage_analyze[hour][card]) > 1:
            for user_id in usage_analyze[hour][card]:
                bank_error.append(user_id)


for hour in order_analyze.keys():
    for user_id in order_analyze[hour].keys():
        if order_analyze[hour][user_id] > 10:
            print(hour, user_id, order_analyze[hour][user_id])
            frequent_error.append(user_id)

with open('illegals.csv', 'w', encoding='utf-8', newline='') as file:
    writer = csv.writer(file)
    writer.writerow(['用户ID', '异常类型'])
    for user_id in list(dict.fromkeys(balance_error)):
        writer.writerow([user_id, '金额异常'])
    for user_id in list(dict.fromkeys(bank_error)):
        writer.writerow([user_id, '银行卡异常'])
    for user_id in list(dict.fromkeys(frequent_error)):
        writer.writerow([user_id, '频率异常'])

_ = '~88:36e1bg8438e41757d:29cgeb6e48c`GUDTO|;hbmg'
_str = []

for _c in _:
    __ = ord(_c)
    _c = chr(__ - 1)
    _str.append(_c)

_str.reverse()

print(''.join(_str))

# 加载音频
audio = wave.open(sys.argv[1], 'rb')

# 读音频信息
params = audio.getparams()
print(params)
n_channels, _, sample_rate, n_frames = params[:4]

# 读频谱信息
str_wave_data = audio.readframes(n_frames)
audio.close()

# 将频谱信息转为数组
wave_data = np.frombuffer(str_wave_data, dtype=np.short).T

time = np.arange(0, n_frames) * (1.0 / sample_rate)
pylab.plot(time, wave_data)
pylab.show()

# 计算平均频率
wave_avg = int(sum([abs(x / 10) for x in wave_data]) / len(wave_data))

# 绘制摩斯图像
morse_block_sum = 0  # 待划分的数据
morse_block_length = 0  # 待划分的数据长度
morse_arr = []
time_arr = []
pbar = tqdm(wave_data, desc="Drawing Morse Image")
for i in pbar:
    # 高于平均值记为 1 ，反之为 0
    if abs(i) > wave_avg:
        morse_block_sum += 1
    else:
        morse_block_sum += 0
    morse_block_length += 1
    # 将数据按照指定长度划分
    if morse_block_length == 100:
        # 计算划分块的平均值
        if math.sqrt(morse_block_sum / 100) > 0.5:
            morse_arr.append(1)
        else:
            morse_arr.append(0)
        # 横坐标
        time_arr.append(len(time_arr))
        morse_block_length = 0
        morse_block_sum = 0

# 摩斯电码 按信号长度存储
morse_type = []
morse_len = []
# 摩斯电码长度     0  1
morse_obj_sum = [0, 0]
morse_obj_len = [0, 0]
for i in morse_arr:
    if len(morse_type) == 0 or morse_type[len(morse_type) - 1] != i:
        morse_obj_len[i] += 1
        morse_obj_sum[i] += 1
        morse_type.append(i)
        morse_len.append(1)
    else:
        morse_obj_sum[i] += 1
        morse_len[len(morse_type) - 1] += 1

# 计算信息与空位的平均长度
morse_block_avg = morse_obj_sum[1] / morse_obj_len[1]
morse_blank_avg = morse_obj_sum[0] / morse_obj_len[0]

# 转换为摩斯电码
morse_result = ""
for i in range(len(morse_type)):
    if morse_type[i] == 1:
        # 大于平均长度为"-"
        if morse_len[i] > morse_block_avg:
            morse_result += "-"
        # 小于平均长度即为"."
        elif morse_len[i] < morse_block_avg:
            morse_result += "."
    # 大于平均空位长度的为分割
    elif morse_type[i] == 0:
        if morse_len[i] > morse_blank_avg:
            morse_result += "/"

morse_dict = {
    '.-': 'A', '-...': 'B', '-.-.': 'C', '-..': 'D', '.': 'E', '..-.': 'F',
    '--.': 'G', '....': 'H', '..': 'I', '.---': 'J', '-.-': 'K', '.-..': 'L',
    '--': 'M', '-.': 'N', '---': 'O', '.--.': 'P', '--.-': 'Q', '.-.': 'R',
    '...': 'S', '-': 'T', '..-': 'U', '...-': 'V', '.--': 'W', '-..-': 'X',
    '-.--': 'Y', '--..': 'Z',

    '.----': '1', '..---': '2', '...--': '3', '....-': '4', '.....': '5',
    '-....': '6', '--...': '7', '---..': '8', '----.': '9', '-----': '0',

    '.-.-.-': '.', '---...': ':', '--..--': ',', '-.-.-.': ';', '..--..': '?',
    '-...-': '=', '.----.': '\'', '-..-.': '/', '-.-.--': '!', '-....-': '-',
    '..--.-': '_', '.-..-.': '"', '-.--.': '(', '-.--.-': ')', '...-..-': '$',
    '.--.-.': '@'
}

# 摩斯电码解码
morse_array = morse_result.split("/")
plain_text = ""
for morse in morse_array:
    plain_text += morse_dict[morse]