X-Git-Url: http://wagner.pp.ru/gitweb/?a=blobdiff_plain;f=ctypescrypto%2Fpkey.py;h=10366ee0b318e1947b4448a1be4f9419884af5b3;hb=766de77591d848bb229ec25ab6b19fb902ee7971;hp=a561ddf23df08bbb7daea0e777ffe00c690b9595;hpb=2f721f8751a08e35ae3a8a63dd53e2d9ab216c47;p=oss%2Fctypescrypto.git

diff --git a/ctypescrypto/pkey.py b/ctypescrypto/pkey.py
index a561ddf..10366ee 100644
--- a/ctypescrypto/pkey.py
+++ b/ctypescrypto/pkey.py
@@ -1,3 +1,10 @@
+"""
+This module provides interface for low-level private/public keypair operation
+
+PKey object of this module is wrapper around OpenSSL EVP_PKEY object.
+"""
+
+
 from ctypes import c_char_p,c_void_p,byref,c_int,c_long, c_longlong, create_string_buffer,CFUNCTYPE,POINTER
 from ctypescrypto import libcrypto
 from ctypescrypto.exception import LibCryptoError,clear_err_stack
@@ -8,6 +15,11 @@ class PKeyError(LibCryptoError):
 
 CALLBACK_FUNC=CFUNCTYPE(c_int,c_char_p,c_int,c_int,c_char_p)
 def password_callback(buf,length,rwflag,u):
+	"""
+	Example password callback for private key. Assumes that 
+	password is store in the userdata parameter, so allows to pass password
+	from constructor arguments to the libcrypto keyloading functions
+	"""
 	cnt=len(u)
 	if length<cnt:
 		cnt=length
@@ -175,6 +187,42 @@ class PKey:
 			raise PKeyError("Error generating key")
 		libcrypto.EVP_PKEY_CTX_free(ctx)
 		return PKey(ptr=key,cansign=True)
+	def exportpub(self,format="PEM"):
+		"""
+			Returns public key as PEM or DER structure.
+		"""
+		b=Membio()
+		if format == "PEM":
+			r=libcrypto.PEM_write_bio_PUBKEY(b.bio,self.key)
+		else:
+			r=libcrypto.i2d_PUBKEY_bio(b.bio,self.key)
+		if r==0:
+			raise PKeyError("error serializing public key")
+		return str(b)
+	def exportpriv(self,format="PEM",password=None,cipher=None):
+		"""
+			Returns private key as PEM or DER Structure.
+			If password and cipher are specified, encrypts key
+			on given password, using given algorithm. Cipher must be
+			an ctypescrypto.cipher.CipherType object
+		"""
+		b=Membio()
+		if cipher is None:
+			evp_cipher=None
+		else:
+			if password is None:
+				raise NotImplementedError("Interactive password entry is not supported")
+			evp_cipher=cipher.cipher
+		if format == "PEM":
+			r=libcrypto.PEM_write_bio_PrivateKey(b.bio,self.key,evp_cipher,None,0,_cb,
+				password)
+		else:
+			if cipher is not None:
+				raise NotImplementedError("Der-formatted encrypted keys are not supported")
+			r=libcrypto.i2d_PrivateKey_bio(b.bio,self.key)
+		if r==0:
+			raise PKeyError("error serializing private key")
+		return str(b)
 	@staticmethod
 	def _configure_context(ctx,opts,skip=[]):
 		"""
@@ -237,4 +285,7 @@ libcrypto.EVP_PKEY_verify.restype=c_int
 libcrypto.EVP_PKEY_verify.argtypes=(c_void_p,c_char_p,c_long,c_char_p,c_long)
 libcrypto.EVP_PKEY_verify_init.restype=c_int
 libcrypto.EVP_PKEY_verify_init.argtypes=(c_void_p,)
-
+libcrypto.PEM_write_bio_PrivateKey.argtypes=(c_void_p,c_void_p,c_void_p,c_char_p,c_int,CALLBACK_FUNC,c_char_p)
+libcrypto.PEM_write_bio_PUBKEY.argtypes=(c_void_p,c_void_p)
+libcrypto.i2d_PUBKEY_bio.argtypes=(c_void_p,c_void_p)
+libcrypto.i2d_PrivateKey_bio.argtypes=(c_void_p,c_void_p)