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diff --git a/ctypescrypto/mac.py b/ctypescrypto/mac.py
new file mode 100644
index 0000000..e5e8f55
--- /dev/null
+++ b/ctypescrypto/mac.py
@@ -0,0 +1,95 @@
+# -*- encoding: utf-8 -*-
+"""
+This module provides interface to OpenSSL MAC functions.
+
+It has not only HMAC support, but can support other types of MAC.
+
+"""
+
+from ctypescrypto.digest import Digest,DigestType,DigestError
+from ctypescrypto.oid import Oid
+from ctypescrypto import libcrypto
+from ctypes import c_int,c_char_p, c_void_p, c_size_t,POINTER,create_string_buffer,pointer
+
+__all__ = ['MAC','DigestError']
+class MAC(Digest):
+	"""
+		This object represents MAC context. It is quite simular
+		to digest algorithm. It is simular to hmac objects provided
+		by standard library
+	"""
+	def __init__(self,algorithm,key,digest=None,**kwargs):
+		"""
+		Constructor has to obligatory arguments:
+			
+			@param algorithm - which is name of MAC algorithm i.e 'hmac' or 
+					'gost-mac' or equivalent Oid object
+			@param key - byte buffer with key.
+
+		Optional parameters are:
+			digest - Oid or name of the digest algorithm to use. If none
+				specified, OpenSSL will try to derive one from the MAC
+				algorithm (or if algorithm is hmac, we'll substititute md5
+				for compatibility with standard hmac module
+
+			any other keyword argument is passed to EVP_PKEY_CTX as string
+			option.
+
+		"""
+		if isinstance(algorithm,str):
+			self.algorithm=Oid(algorithm)
+		elif isinstance(algorithm,Oid):
+			self.algorithm=algorithm
+		else:
+			raise TypeError("Algorthm must be string or Oid")
+		if self.algorithm==Oid('hmac') and digest is None:
+				digest='md5'
+		self.name=self.algorithm.shortname().lower()
+		if digest is not None:
+			self.digest_type=DigestType(digest)
+			self.name+='-'+self.digest_type.digest_name
+			d=self.digest_type.digest
+		else:
+			self.digest_type=None
+			d=None
+		self.key=libcrypto.EVP_PKEY_new_mac_key(self.algorithm.nid,None,key,len(key))
+		if self.key is None:
+			raise DigestError("EVP_PKEY_new_mac_key")
+		pctx=c_void_p()
+		self.ctx = libcrypto.EVP_MD_CTX_create()
+		if self.ctx == 0:
+			raise DigestError("Unable to create digest context")
+		if libcrypto.EVP_DigestSignInit(self.ctx,pointer(pctx),d,None,self.key) <= 0:
+			raise DigestError("Unable to intialize digest context")
+		self.digest_finalized=False
+		if self.digest_type is None:
+			self.digest_type=DigestType(Oid(libcrypto.EVP_MD_type(libcrypto.EVP_MD_CTX_md(self.ctx))))
+		for (name,val) in kwargs.items():
+			if EVP_PKEY_CTX_ctrl_str(ctx,name,val)<=0:
+				raise DigestError("Unable to set mac parameter")
+		self.digest_size = self.digest_type.digest_size()
+		self.block_size = self.digest_type.block_size()
+	def digest(self,data=None):
+		"""
+		Method digest is redefined to return keyed MAC value instead of
+		just digest.
+		"""
+		if data is not None:
+			self.update(data)
+		b=create_string_buffer(256)
+		size=c_size_t(256)
+		if libcrypto.EVP_DigestSignFinal(self.ctx,b,pointer(size))<=0:
+			raise DigestError('SignFinal')
+		self.digest_finalized=True
+		return b.raw[:size.value]
+
+libcrypto.EVP_DigestSignFinal.argtypes=(c_void_p,c_char_p,POINTER(c_size_t))
+libcrypto.EVP_DigestSignFinal.restype=c_int
+libcrypto.EVP_DigestSignInit.argtypes=(c_void_p,POINTER(c_void_p),c_void_p,c_void_p,c_void_p)
+libcrypto.EVP_DigestSignInit.restype=c_int
+libcrypto.EVP_PKEY_CTX_ctrl_str.argtypes=(c_void_p,c_char_p,c_char_p)
+libcrypto.EVP_PKEY_CTX_ctrl_str.restype=c_int
+libcrypto.EVP_PKEY_new_mac_key.argtypes=(c_int,c_void_p,c_char_p,c_int)
+libcrypto.EVP_PKEY_new_mac_key.restype=c_void_p
+libcrypto.EVP_MD_CTX_md.argtypes=(c_void_p,)
+libcrypto.EVP_MD_CTX_md.restype=c_void_p