base64位加解密专题研究

实现破解自定义加解密的破解方法

import base64

def custom_base64_encode(data, custom_charset):
    encoded_chars = []
    for byte in data:
        encoded_chars.append(custom_charset[byte >> 2 & 0x3F])
        encoded_chars.append(custom_charset[(byte & 0x03) << 4])
    return ''.join(encoded_chars)

def custom_base64_decode(data, custom_charset):
    decoded_chars = []
    for i in range(0, len(data), 2):
        char1 = custom_charset.index(data[i])
        char2 = custom_charset.index(data[i+1])
        byte = (char1 << 2) | (char2 >> 4)
        decoded_chars.append(byte)
    return bytes(decoded_chars)

# 自定义base64字符集
custom_charset = "123456ertyuytdf456ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz+"

# 原始数据
original_data = b"Hello, World!"

# 标准base64编码
standard_encoded_data = base64.b64encode(original_data).decode()

# 自定义base64编码
custom_encoded_data = custom_base64_encode(original_data, custom_charset)

# 标准base64解码
standard_decoded_data = base64.b64decode(standard_encoded_data)

# 自定义base64解码
custom_decoded_data = custom_base64_decode(custom_encoded_data, custom_charset)

print("原始数据:", original_data)
print("标准base64编码:", standard_encoded_data)
print("自定义base64编码:", custom_encoded_data)
print("标准base64解码:", standard_decoded_data)