api_py/xhs/shield.py

import base64

from xhs.shield_aes import get_key
from xhs.shield_md5 import md5sum
from xhs.shield_rc4 import RC4


def hex_string(num, step=2):
    """
    step 控制二进制的长度 避免有些少零了
    """
    tmp_string = hex(num)[2:]

    if len(tmp_string) < step:
        tmp_string = '0' + tmp_string

    return tmp_string


def expand_keys(keys, m):
    md5_str1_list = [hex_string(int(keys[i] + keys[i + 1], 16) ^ m) for i in range(0, len(keys), 2)]
    md5_str1 = "".join(md5_str1_list)
    return md5_str1


def char2hex(char):
    return hex_string(ord(char))


def get_md5(keys, params):
    """
    标准 hmac 操作
    :param keys:
    :param params:
    :return:
    """

    # 拓展key1 0x36
    md5_str1 = expand_keys(keys, 54)
    # 拓展key2 0x5c
    md5_str2 = expand_keys(keys, 92)

    data = bytes.fromhex(md5_str1) + params.encode("utf-8")
    md1 = md5sum(data)

    data1 = bytes.fromhex(md5_str2 + md1)
    md2 = md5sum(data1)  # 获得最终结果

    return md2


def get_rc4(params):
    """
    标准rc4运算
    :param params:
    :return:
    """
    key = "std::abort();"
    result = RC4(key.encode("utf-8"), bytes.fromhex(params))
    return result.hex()


def get_shield(keys, params, deviceId):
    """
    shield生成核心部分
    固定版本 和 app_id
    :param keys:
    :param params:
    :param deviceId:
    :return:
    """
    version = "6970181"
    app_id = "ecfaaf01"
    p7 = "".join([char2hex(m) for m in version])
    p8 = "".join([char2hex(m) for m in deviceId])
    p9 = get_md5(keys, params)  # 魔改md5 16位md5
    rc4_plaintext = f"00000001{app_id}00000002000000{hex_string(len(version))}000000{hex_string(len(deviceId))}000000{hex_string(len(p9) // 2)}{p7}{p8}{p9}"
    result = get_rc4(rc4_plaintext)
    _tmp = len(version) + len(deviceId) + len(p9) // 2 + 24
    tmp = f"0000000100000001000000{hex_string(_tmp)}000000{hex_string(_tmp)}"  # 固定 0x53是上述 几个固定的值算出来的
    _shield = "XY" + base64.b64encode(bytes.fromhex(tmp + result)).decode()
    return _shield


def shield(node_id, xy_common_params, xy_platform_info):
    """

    """
    # 设备一
    deviceId = "2fe75062-a528-3340-bed3-220a67f7f240"
    keys = "aa82da57410dddd5b2860e534f7c0602f589c20ec8e8830baa239360c89cce62bdc304d8a1aa988d620917dbefc2a1154692fad24294f4419ea19c7dc069897b"

    api = "/api/sns/v1/note/feed"
    param = f"note_id={node_id}&page=1&num=5&fetch_mode=1&source=&ads_track_id="
    plaintext = api + param + xy_common_params + xy_platform_info
    return get_shield(keys, plaintext, deviceId)


def shield_run(url, keys, xy_common_params, deviceId, api="/api/sns/v1/note/feed"):
    """
    对外暴露接口
    :param url: 请求的链接
    :param keys: 参与运算的 hmac_main
    :param xy_common_params: 对应header中字段
    :param deviceId: 对应设备号
    :param api: 对应接口 目前默认为feed流接口
    :return:
    """
    param = url[url.index("?") + 1:]
    xy_platform_info = f"platform=android&build=6970181&deviceId={deviceId}"
    plaintext = api + param + xy_common_params + xy_platform_info
    # print(plaintext)
    return get_shield(keys, plaintext, deviceId)


if __name__ == '__main__':
    # 先获得 main_hmac 处理后的key
    # XYAAAAAQAAAAEAAABTAAAAUzUWEe0xG1IbD9/c+qCLOlKGmTtFa+lG43AHe+FXTKxDxI2yn7IxH534qbVaz8N7icV+2KNmRAwcQDSAZrqn3SpjhOCLuaGTuDRgbpA0sNhU/xUP 结果
    # XYAAAAAQAAAAEAAABTAAAAUzUWEe0xG1IbD9/c+qCLOlKGmTtFa+lG43AHe+FXTKxDxI2yn7IxH534qbVaz8N7icV+2KNmRAwcQDSAZrqn3SpjhOCLuaGTuDRgbpA0sNhU/xUP
    # keys = "aa82da57410dddd5b2860e534f7c0602f589c20ec8e8830baa239360c89cce62bdc304d8a1aa988d620917dbefc2a1154692fad24294f4419ea19c7dc069897b"
    # get_shield(keys)
    url = "https://edith.xiaohongshu.com/api/sns/v1/note/feed?note_id=66ceeabe000000001d03b546&page=1&num=5&fetch_mode=1&source=&ads_track_id="

    hmac = "NqLx0YFKNb4KraYq524SgzVpepYQ0SwhZLRs7eyxe6A26c/b1b+d6OU2LfAPwh8zpt3fkR/jsR5yzVzIqXe66EWhGJ8iWV36KKSIz0mVt436sTqt3eUYUZwb5TzpSYDa"
    deviceId = "119214fc-0fe5-3ae8-91dd-baa821c11324"
    xy_platform_info = "platform=android&build=6970181&deviceId=119214fc-0fe5-3ae8-91dd-baa821c11324"
    xy_common_params = "fid=1721639154103483c0daaace2ca9266cba37ac9fe114&device_fingerprint=202407221758192809006e7e334e46628620f6768bcf3b0153b1977b9f6cd6&device_fingerprint1=202407221758192809006e7e334e46628620f6768bcf3b0153b1977b9f6cd6&cpu_name=Qualcomm+Technologies%2C+Inc+SM8150&device_model=phone&launch_id=1727578036&tz=Asia%2FShanghai&channel=CPA-3DSP-N3-ZSKJ&versionName=6.97.0.1&overseas_channel=0&deviceId=119214fc-0fe5-3ae8-91dd-baa821c11324&platform=android&sid=session.1721639201142076381131&identifier_flag=4&t=1727590998&project_id=ECFAAF&build=6970181&lang=zh-Hans&app_id=ECFAAF01&uis=dark&teenager=0"

    keys = get_key(deviceId, hmac)

    result = sheild_run(url, keys, xy_common_params, deviceId)
    print(result)