class _Hmac(_Hash):
"""
A **PEP 247: Cryptographic Hash Functions** compliant
**Keyed Hash Function Interface**.
"""
digest_size = None
_native_type = "Hmac *"
_native_size = _ffi.sizeof("Hmac")
def __init__(self, key, string=None): # pylint: disable=W0231
key = t2b(key)
self._native_object = _ffi.new(self._native_type)
ret = self._init(self._type, key)
if ret < 0: # pragma: no cover
raise WolfCryptError("Hmac init error (%d)" % ret)
if string:
self.update(string)
@classmethod
def new(cls, key, string=None): # pylint: disable=W0221
"""
Creates a new hashing object and returns it. **key** is
a required parameter containing a string giving the key
to use. The optional **string** parameter, if supplied,
will be immediately hashed into the object's starting
state, as if obj.update(string) was called.
"""
return cls(key, string)
def _init(self, hmac, key):
if _lib.wc_HmacInit(self._native_object, _ffi.NULL, -2) != 0:
raise WolfCryptError("wc_HmacInit error")
# If the key isn't set, don't call wc_HmacSetKey. This can happen,
# for example, when the HMAC object is being copied. See the copy
# function of _Hash.
ret = 0
if len(key) > 0:
ret = _lib.wc_HmacSetKey(self._native_object, hmac, key,
len(key))
if ret < 0:
err_str = "no error description found"
try:
err_str = _ffi.string(
_lib.wc_GetErrorString(ret)).decode()
except:
pass
raise WolfCryptError(
"wc_HmacSetKey returned {}: {}".format(ret, err_str))
return ret
def _update(self, data):
return _lib.wc_HmacUpdate(self._native_object, data, len(data))
def _final(self, obj, ret):
return _lib.wc_HmacFinal(obj, ret)
class Sha(_Hash):
"""
**SHA-1** is a cryptographic hash function standardized by **NIST**.
It produces an [ **160-bit | 20 bytes** ] message digest.
"""
digest_size = 20
_native_type = "Sha *"
_native_size = _ffi.sizeof("Sha")
def _init(self):
return _lib.wc_InitSha(self._native_object)
def _update(self, data):
return _lib.wc_ShaUpdate(self._native_object, data, len(data))
def _final(self, obj, ret):
return _lib.wc_ShaFinal(obj, ret)
class Sha512(_Hash):
"""
**SHA-512** is a cryptographic hash function from the
**SHA-2 family** and is standardized by **NIST**.
It produces a [ **512-bit | 64 bytes** ] message digest.
"""
digest_size = 64
_native_type = "Sha512 *"
_native_size = _ffi.sizeof("Sha512")
def _init(self):
return _lib.wc_InitSha512(self._native_object)
def _update(self, data):
return _lib.wc_Sha512Update(self._native_object, data, len(data))
def _final(self, obj, ret):
return _lib.wc_Sha512Final(obj, ret)
class Sha384(_Hash):
"""
**SHA-384** is a cryptographic hash function from the
**SHA-2 family** and is standardized by **NIST**.
It produces a [ **384-bit | 48 bytes** ] message digest.
"""
digest_size = 48
_native_type = "wc_Sha384 *"
_native_size = _ffi.sizeof("wc_Sha384")
def _init(self):
return _lib.wc_InitSha384(self._native_object)
def _update(self, data):
return _lib.wc_Sha384Update(self._native_object, data, len(data))
def _final(self, obj, ret):
return _lib.wc_Sha384Final(obj, ret)
class _Hmac(_Hash):
"""
A **PEP 247: Cryptographic Hash Functions** compliant
**Keyed Hash Function Interface**.
"""
digest_size = None
_native_type = "Hmac *"
_native_size = _ffi.sizeof("Hmac")
def __init__(self, key, string=None):
key = t2b(key)
self._native_object = _ffi.new(self._native_type)
ret = self._init(self._type, key)
if ret < 0:
raise WolfCryptError("Hmac init error (%d)" % ret)
if (string):
self.update(string)
@classmethod
def new(cls, key, string=None):
"""
Creates a new hashing object and returns it. **key** is
a required parameter containing a string giving the key
to use. The optional **string** parameter, if supplied,
will be immediately hashed into the object's starting
state, as if obj.update(string) was called.
"""
return cls(key, string)
def _init(self, type, key):
return _lib.wc_HmacSetKey(self._native_object, type, key, len(key))
def _update(self, data):
return _lib.wc_HmacUpdate(self._native_object, data, len(data))
def _final(self, obj, ret):
return _lib.wc_HmacFinal(obj, ret)
class Sha3(_Hash):
"""
**SHA3 ** is a cryptographic hash function family
standardized by **NIST**.
It produces from [ **224-bit | 28 bytes** ] up to [ **512-bit | 64 bytes] message digests.
Using SHA3-384 by default, unless a different digest size is passed through __init__.
"""
_native_type = "wc_Sha3 *"
_native_size = _ffi.sizeof("wc_Sha3")
SHA3_224_DIGEST_SIZE = 28
SHA3_256_DIGEST_SIZE = 32
SHA3_384_DIGEST_SIZE = 48
SHA3_512_DIGEST_SIZE = 64
def __init__(self): # pylint: disable=W0231
self._native_object = _ffi.new(self._native_type)
self.digest_size = SHA3_384_DIGEST_SIZE
ret = self._init()
if ret < 0: # pragma: no cover
raise WolfCryptError("Sha3 init error (%d)" % ret)
def __init__(self, string, size=SHA3_384_DIGEST_SIZE): # pylint: disable=W0231
self._native_object = _ffi.new(self._native_type)
self.digest_size = size
ret = self._init()
if ret < 0: # pragma: no cover
raise WolfCryptError("Sha3 init error (%d)" % ret)
if string:
self.update(string)
def _init(self):
if (self.digest_size != Sha3.SHA3_224_DIGEST_SIZE
and self.digest_size != Sha3.SHA3_256_DIGEST_SIZE
and self.digest_size != Sha3.SHA3_384_DIGEST_SIZE
and self.digest_size != Sha3.SHA3_512_DIGEST_SIZE):
return -1
if self.digest_size == Sha3.SHA3_224_DIGEST_SIZE:
return _lib.wc_InitSha3_224(self._native_object, _ffi.NULL, 0)
if self.digest_size == Sha3.SHA3_256_DIGEST_SIZE:
return _lib.wc_InitSha3_256(self._native_object, _ffi.NULL, 0)
if self.digest_size == Sha3.SHA3_384_DIGEST_SIZE:
return _lib.wc_InitSha3_384(self._native_object, _ffi.NULL, 0)
if self.digest_size == Sha3.SHA3_512_DIGEST_SIZE:
return _lib.wc_InitSha3_512(self._native_object, _ffi.NULL, 0)
def _update(self, data):
if self.digest_size == Sha3.SHA3_224_DIGEST_SIZE:
return _lib.wc_Sha3_224_Update(self._native_object, data,
len(data))
if self.digest_size == Sha3.SHA3_256_DIGEST_SIZE:
return _lib.wc_Sha3_256_Update(self._native_object, data,
len(data))
if self.digest_size == Sha3.SHA3_384_DIGEST_SIZE:
return _lib.wc_Sha3_384_Update(self._native_object, data,
len(data))
if self.digest_size == Sha3.SHA3_512_DIGEST_SIZE:
return _lib.wc_Sha3_512_Update(self._native_object, data,
len(data))
def _final(self, obj, ret):
if self.digest_size == Sha3.SHA3_224_DIGEST_SIZE:
return _lib.wc_Sha3_224_Final(obj, ret)
if self.digest_size == Sha3.SHA3_256_DIGEST_SIZE:
return _lib.wc_Sha3_256_Final(obj, ret)
if self.digest_size == Sha3.SHA3_384_DIGEST_SIZE:
return _lib.wc_Sha3_384_Final(obj, ret)
if self.digest_size == Sha3.SHA3_512_DIGEST_SIZE:
return _lib.wc_Sha3_512_Final(obj, ret)
