关于Requests交互超时的处理方式

拿 https://aes.cryptohack.org/ecb_oracle 这道题来做示范。

由于这个链接的本地服务器在外国，因此我们很容易就会连接超时。

如下一个脚本：

import requests
from tqdm import *
from Crypto.Util.number import *
known = b''

for i in range(31, 0, -1):
    text = hex(bytes_to_long(b'0' * i))[2:]
    result = s.get(f'http://aes.cryptohack.org/ecb_oracle/encrypt/{text}')
    t1 = result.json()["ciphertext"]
    print(t1)
    for j in range(0x31, 0x80):
        n = b'0' * i + known + long_to_bytes(j)
        text = hex(bytes_to_long(n))[2:]
        # print(text)
        guess = s.get(f'http://aes.cryptohack.org/ecb_oracle/encrypt/{text}')
        t2 = guess.json()["ciphertext"]
        print(t2)
        if t1[32:64] == t2[32:64]:
            known += long_to_bytes(j)
            print(known)
            break
    if known[len(known) - 1] == b'}':
        break
print(known)

我们可以通过修改 requests 参数来修改重连次数，超时时间。

# 修改最大重连次数
requests.adapters.DEFAULT_RETRIES = 100000

# 新建一个容器
s = requests.Session()

# 将 timeout 变量中连接超时时间和接收超时时间改变（默认为10）
s.timeout = (1000.0, 1000.0)

于是下面这份代码就可以较为稳定的连接了。

import requests
from tqdm import *
from Crypto.Util.number import *
known = b''

requests.adapters.DEFAULT_RETRIES = 100000
s = requests.Session()
s.timeout = (1000.0, 1000.0)

for i in range(31, 0, -1):
    text = hex(bytes_to_long(b'0' * i))[2:]
    result = s.get(f'http://aes.cryptohack.org/ecb_oracle/encrypt/{text}')
    t1 = result.json()["ciphertext"]
    print(t1)
    for j in range(0x31, 0x80):
        n = b'0' * i + known + long_to_bytes(j)
        text = hex(bytes_to_long(n))[2:]
        # print(text)
        guess = s.get(f'http://aes.cryptohack.org/ecb_oracle/encrypt/{text}')
        t2 = guess.json()["ciphertext"]
        print(t2)
        if t1[32:64] == t2[32:64]:
            known += long_to_bytes(j)
            print(known)
            break
    if known[len(known) - 1] == b'}':
        break
print(known)

# crypto{p3n6u1n5_h473_3cb}