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SHA1算法的源代码是如何实现加密过程的?

SHA1是一种密码散列函数,用于生成消息摘要。它接收输入并产生一个160位的哈希值。

SHA1是一种密码散列函数,它可以将任意长度的数据转换为固定长度的哈希值,以下是一个简单的Python实现:

SHA1算法的源代码是如何实现加密过程的?  第1张

import struct
def left_rotate(n, b):
    return ((n << b) | (n >> (32  b))) & 0xffffffff
def sha1(data):
    bytes = ""
    h0 = 0x67452301
    h1 = 0xEFCDAB89
    h2 = 0x98BADCFE
    h3 = 0x10325476
    h4 = 0xC3D2E1F0
    for n in range(len(data)):
        bytes += '{0:08b}'.format(ord(data[n]))
    bits = bytes + "1"
    pBits = bits
    while len(pBits) % 512 != 448:
        pBits += "0"
    pBits += '{0:064b}'.format(len(bits)  1)
    for c in range(len(pBits) // 512):
        words = [0] * 80
        chunk = pBits[c * 512:(c + 1) * 512]
        for i in range(16):
            words[i] = int(chunk[i * 32:i * 32 + 32], 2)
        for i in range(16, 80):
            words[i] = left_rotate(words[i  3] ^ words[i  8] ^ words[i  14] ^ words[i  16], 1)
        a = h0
        b = h1
        c = h2
        d = h3
        e = h4
        for i in range(80):
            if 0 <= i <= 19:
                f = (b & c) | ((~b) & d)
                k = 0x5A827999
            elif 20 <= i <= 39:
                f = b ^ c ^ d
                k = 0x6ED9EBA1
            elif 40 <= i <= 59:
                f = (b & c) | (b & d) | (c & d)
                k = 0x8F1BBCDC
            elif 60 <= i <= 79:
                f = b ^ c ^ d
                k = 0xCA62C1D6
            temp = left_rotate(a, 5) + f + e + k + words[i] & 0xffffffff
            e = d
            d = c
            c = left_rotate(b, 30)
            b = a
            a = temp
        h0 = h0 + a & 0xffffffff
        h1 = h1 + b & 0xffffffff
        h2 = h2 + c & 0xffffffff
        h3 = h3 + d & 0xffffffff
        h4 = h4 + e & 0xffffffff
    return '%08x%08x%08x%08x%08x' % (h0, h1, h2, h3, h4)
if __name__ == "__main__":
    data = "Hello, World!"
    print("SHA1 hash of '{}': {}".format(data, sha1(data)))

这个代码实现了SHA1算法,首先将输入数据转换为二进制字符串,然后按照SHA1算法的规则进行填充和处理,将计算得到的哈希值以十六进制字符串的形式返回。

以上内容就是解答有关“sha1源码”的详细内容了,我相信这篇文章可以为您解决一些疑惑,有任何问题欢迎留言反馈,谢谢阅读。

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