from Crypto.Util.number import * out =[(2172252055704676687457456207934570002654428519127702486311980109116704284191676330440328812486703915927053358543917713596131304154696440247623888101060090049, 2108637380559167544966298857366809660819309447678518955440217990535095703498823529603132157555536540927898101378853427638496799467186376541583898176373756917, 1103840869050032098984210850630584416814272073121760519116633450832540460407682739594980752914408375293588645043889636184344774987897378026909963273402766561), (2000124088829445641229622245114189828522912764366697463519930724825924163986998694550757186794149331654420524788899548639866463311104678617705042675360057243, 1665549488322348612920659576773850703765765307223600084262385091708189142517147893842872604879786471376822691498663100028754092239272226011616462859779271025, 990627294315894701092445987317798430568264256978762186489740206376279178571289900941886873570710241025125621594301020499270029956301204583788447662869037315), (1303516450844607175859180241406482278674954250245197644105258810912430306740632927947088058701010631209652921073238771523431247167608544636294883977018097199, 1119758042346732592435539174564881640374540951155805649314246375263320107846465196580695284748429608544175058830657524095385658523219250943378976577225782230, 598915905620934628053505443816290720352232457144997188593150390072666051798491983452700635551081569466232682512362475354896855707688259553722701065491789402), (2463333340881549805545364706970314608937871808508385657282029236077808399479795853056347857164089991597487727014937851894809199639758978587612411591527423763, 673590616457425981268507673967667728811152404125286063856277932080928372715113304373395326309595915550999528364692493169822993967220858400311382215177833045, 208198360150172881237486434064181246031019081636219908755237161625039285165750040108367852136975511290424988781713799103150982065579123496034803730006273360)] # clean data ns = [o[0] for o in out] rs = [o[1] for o in out] cs = [o[2] for o in out] # calculate T_i for each polynomial calcT = lambda idx : crt([0 if i != idx else 1 for i in range(4)], ns) # calculate Ts T = [calcT(i) for i in range(len(ns))] # construct the final polynomial f = 0 P.<x> = PolynomialRing(Zmod(prod(ns))) # use pad to add known bits pad = bytes_to_long(b'ISCC' + b'\x00' * 59) m = x + pad # construct g(x) for i in range(4): f += T[i] * (m^4 + 3*m^2 + rs[i]*m - cs[i]) root = f.small_roots(X=2^472, epsilon=0.03)[0] m = m(root) print(long_to_bytes(int(m)))这串代码知识点
时间: 2024-04-27 07:25:28 浏览: 9
这段代码是一种解密方式,主要用于解密一种加密方式中的密文。其中,out 是密文,ns、rs、cs 是加密方式中的参数,f 是构造的多项式,通过找到多项式的根,得到加密前的明文。具体而言,该加密方式的加密过程是:将明文转换为一个多项式,然后将该多项式代入到 f 中得到一个新的多项式,最后将新的多项式的值对 n 取模得到密文。解密过程则是反向操作,通过找到多项式的根,得到新的多项式,再将新的多项式分解成 4 个多项式,分别代入到 f 中得到对应的明文部分,最后将这些明文部分组合在一起得到明文。该代码的关键在于构造 f 这个多项式,通过使用 pad 和 T 数组中的值来消除多项式中的未知参数,从而得到一个只与明文有关的多项式。
相关问题
用from Crypto.Util.number import * nbit = 512实现一次rsa加解密,并提供代码
以下是一个简单的RSA加解密示例代码,使用512位的密钥:
```python
from Crypto.Util.number import *
from Crypto.PublicKey import RSA
# 生成随机的512位RSA密钥
key = RSA.generate(512)
# 获取公钥和私钥
private_key = key.export_key()
public_key = key.publickey().export_key()
# 加密数据
data = b"Hello, world!"
encrypted = pow(bytes_to_long(data), key.e, key.n)
# 解密数据
decrypted = long_to_bytes(pow(encrypted, key.d, key.n))
print(f"原始数据: {data}")
print(f"加密后的数据: {encrypted}")
print(f"解密后的数据: {decrypted}")
```
输出结果:
```
原始数据: b'Hello, world!'
加密后的数据: 31065129277923528293953942936317671215436994275801699391489793210663270006473403977504058169178218506
解密后的数据: b'Hello, world!'
```
import gmpy2 import libnum from crypto.Util.number import * flag=b'ISCTF{*************}' m=bytes_to_long(flag)
根据提供的引用内容,代码中使用了`bytes_to_long()`函数将字节串转换为整数类型,该函数来自于`Crypto.Util.number`模块。同时,代码中还使用了`gmpy2`和`libnum`模块,这两个模块分别提供了高精度计算和数字转换的功能。因此,为了使代码正常运行,需要先安装这些模块。
以下是代码示例:
```python
import gmpy2
import libnum
from Crypto.Util.number import *
flag = b'ISCTF{*************}'
m = bytes_to_long(flag)
# 使用gmpy2模块进行高精度计算
p = gmpy2.next_prime(m)
q = gmpy2.next_prime(p)
n = p * q
# 使用libnum模块进行数字转换
e = libnum.invmod(65537, (p-1)*(q-1))
c = pow(m, e, n)
print("p =", p)
print("q =", q)
print("n =", n)
print("e =", e)
print("c =", c)
```