2

我不会在 php 中实现在 web2py 中完成的密码哈希,现在我从 massimo de piero 创建的 web2py 中得到了一些关于如何做到这一点的说明,但我仍然无法在 php 中实现它,说明如下:

逻辑非常复杂,因为它需要处理许多选项并且不破坏向后兼容性。

通常哈希密码看起来像

算法$salt$hash 算法$$hash(无盐)hash(遗留)

哈希使用算法、盐和可选的用户提供的密钥进行计算。钥匙是独一无二的。每个密码的盐是不同的。

每次调用 CRYPT()('password') 时,都会得到一个 LazyCrypt 对象。该对象可以序列化为字符串。你得到的字符串总是不同的,因为它包含一个随机的盐。您无法比较其中两个字符串,因为即使密码相同,您也总是会得到错误。然而,您可以将 LazyObject 与字符串进行比较,并且惰性对象将使用相同的算法和字符串中的相同盐来计算哈希并将其与字符串中的哈希进行比较。例子:

>>> a = CRYPT()('password')
>>> b = CRYPT()('password')
>>> sa = str(a)
>>> sb = str(b)
>>> sa == sb
False
>>> a == sb
True
>>> c = CRYPT()('wrong')
>>> c == sb
False

以下是 web2py 框架中用于实现该加密的类:

class LazyCrypt(object):
    """
    Stores a lazy password hash
    """

    def __init__(self, crypt, password):
        """
        crypt is an instance of the CRYPT validator,
        password is the password as inserted by the user
        """
        self.crypt = crypt
        self.password = password
        self.crypted = None

    def __str__(self):
        """
        Encrypted self.password and caches it in self.crypted.
        If self.crypt.salt the output is in the format <algorithm>$<salt>$<hash>
        Try get the digest_alg from the key (if it exists)
        else assume the default digest_alg. If not key at all, set key=''
        If a salt is specified use it, if salt is True, set salt to uuid
        (this should all be backward compatible)
        Options:
        key = 'uuid'
        key = 'md5:uuid'
        key = 'sha512:uuid'
        ...
        key = 'pbkdf2(1000,64,sha512):uuid' 1000 iterations and 64 chars length
        """
        if self.crypted:
            return self.crypted
        if self.crypt.key:
            if ':' in self.crypt.key:
                digest_alg, key = self.crypt.key.split(':', 1)
            else:
                digest_alg, key = self.crypt.digest_alg, self.crypt.key
        else:
            digest_alg, key = self.crypt.digest_alg, ''
        if self.crypt.salt:
            if self.crypt.salt == True:
                salt = str(web2py_uuid()).replace('-', '')[-16:]
            else:
                salt = self.crypt.salt
        else:
            salt = ''

        hashed = simple_hash(self.password, key, salt, digest_alg)
        self.crypted = '%s$%s$%s' % (digest_alg, salt, hashed)
        return self.crypted

    def __eq__(self, stored_password):
        """
        compares the current lazy crypted password with a stored password
        """
        # LazyCrypt objects comparison
        if isinstance(stored_password, self.__class__):
            return ((self is stored_password) or
                   ((self.crypt.key == stored_password.crypt.key) and
                   (self.password == stored_password.password)))

        if self.crypt.key:
            if ':' in self.crypt.key:
                key = self.crypt.key.split(':')[1]
            else:
                key = self.crypt.key
        else:
            key = ''
        if stored_password is None:
            return False
        elif stored_password.count('$') == 2:
            (digest_alg, salt, hash) = stored_password.split('$')
            h = simple_hash(self.password, key, salt, digest_alg)
            temp_pass = '%s$%s$%s' % (digest_alg, salt, h)
        else:  # no salting
            # guess digest_alg
            digest_alg = DIGEST_ALG_BY_SIZE.get(len(stored_password), None)

            if not digest_alg:
                return False
            else:
                temp_pass = simple_hash(self.password, key, '', digest_alg)
        return temp_pass == stored_password


class CRYPT(object):

    """
    example::
        INPUT(_type='text', _name='name', requires=CRYPT())
    encodes the value on validation with a digest.
    If no arguments are provided CRYPT uses the MD5 algorithm.
    If the key argument is provided the HMAC+MD5 algorithm is used.
    If the digest_alg is specified this is used to replace the
    MD5 with, for example, SHA512. The digest_alg can be
    the name of a hashlib algorithm as a string or the algorithm itself.
    min_length is the minimal password length (default 4) - IS_STRONG for serious security
    error_message is the message if password is too short

    Notice that an empty password is accepted but invalid. It will not allow login back.

    Stores junk as hashed password.
    Specify an algorithm or by default we will use sha512.
    Typical available algorithms:
      md5, sha1, sha224, sha256, sha384, sha512

    If salt, it hashes a password with a salt.
    If salt is True, this method will automatically generate one.
    Either case it returns an encrypted password string in the following format:

      <algorithm>$<salt>$<hash>

    Important: hashed password is returned as a LazyCrypt object and computed only if needed.
    The LasyCrypt object also knows how to compare itself with an existing salted password

    Supports standard algorithms

    >>> for alg in ('md5','sha1','sha256','sha384','sha512'):

    ...     print str(CRYPT(digest_alg=alg,salt=True)('test')[0])
    md5$...$...
    sha1$...$...
    sha256$...$...
    sha384$...$...
    sha512$...$...

    The syntax is always alg$salt$hash

    Supports for pbkdf2
    >>> alg = 'pbkdf2(1000,20,sha512)'
    >>> print str(CRYPT(digest_alg=alg,salt=True)('test')[0])
    pbkdf2(1000,20,sha512)$...$...

    An optional hmac_key can be specified and it is used as salt prefix
    >>> a = str(CRYPT(digest_alg='md5',key='mykey',salt=True)('test')[0])
    >>> print a
    md5$...$...

    Even if the algorithm changes the hash can still be validated
    >>> CRYPT(digest_alg='sha1',key='mykey',salt=True)('test')[0] == a
    True

    If no salt is specified CRYPT can guess the algorithms from length:
    >>> a = str(CRYPT(digest_alg='sha1',salt=False)('test')[0])
    >>> a
    'sha1$$a94a8fe5ccb19ba61c4c0873d391e987982fbbd3'
    >>> CRYPT(digest_alg='sha1',salt=False)('test')[0] == a
    True
    >>> CRYPT(digest_alg='sha1',salt=False)('test')[0] == a[6:]
    True
    >>> CRYPT(digest_alg='md5',salt=False)('test')[0] == a
    True
    >>> CRYPT(digest_alg='md5',salt=False)('test')[0] == a[6:]
    True
    """

    def __init__(self,
                 key=None,
                 digest_alg='pbkdf2(1000,20,sha512)',
                 min_length=0,
                 error_message='too short', salt=True):

        """
        important, digest_alg='md5' is not the default hashing algorithm for
        web2py. This is only an example of usage of this function.

        The actual hash algorithm is determined from the key which is
        generated by web2py in tools.py. This defaults to hmac+sha512.
        """

        self.key = key
        self.digest_alg = digest_alg
        self.min_length = min_length
        self.error_message = error_message
        self.salt = salt

    def __call__(self, value):
        if len(value) < self.min_length:
            return ('', translate(self.error_message))
        return (LazyCrypt(self, value), None) 

希望有人能指导我一点,最好的问候,

4

1 回答 1

0

您想使用password_hash()andpassword_verify()而不是crypt()直接使用。

于 2018-11-01T22:08:35.567 回答