"""Factory functions for asymmetric cryptography.
@sort: generateRSAKey, parseXMLKey, parsePEMKey, parseAsPublicKey,
parseAsPrivateKey
"""
from compat import *
from RSAKey import RSAKey
from Python_RSAKey import Python_RSAKey
import cryptomath
if cryptomath.m2cryptoLoaded:
from OpenSSL_RSAKey import OpenSSL_RSAKey
if cryptomath.pycryptoLoaded:
from PyCrypto_RSAKey import PyCrypto_RSAKey
# **************************************************************************
# Factory Functions for RSA Keys
# **************************************************************************
def generateRSAKey(bits, implementations=["openssl", "python"]):
"""Generate an RSA key with the specified bit length.
@type bits: int
@param bits: Desired bit length of the new key's modulus.
@rtype: L{tlslite.utils.RSAKey.RSAKey}
@return: A new RSA private key.
"""
for implementation in implementations:
if implementation == "openssl" and cryptomath.m2cryptoLoaded:
return OpenSSL_RSAKey.generate(bits)
elif implementation == "python":
return Python_RSAKey.generate(bits)
raise ValueError("No acceptable implementations")
def parseXMLKey(s, private=False, public=False, implementations=["python"]):
"""Parse an XML-format key.
The XML format used here is specific to tlslite and cryptoIDlib. The
format can store the public component of a key, or the public and
private components. For example::
4a5yzB8oGNlHo866CAspAC47M4Fvx58zwK8pou...
Aw==4a5yzB8oGNlHo866CAspAC47M4Fvx58zwK8pou...
Aw==JZ0TIgUxWXmL8KJ0VqyG1V0J3ern9pqIoB0xmy...
@type s: str
@param s: A string containing an XML public or private key.
@type private: bool
@param private: If True, a L{SyntaxError} will be raised if the private
key component is not present.
@type public: bool
@param public: If True, the private key component (if present) will be
discarded, so this function will always return a public key.
@rtype: L{tlslite.utils.RSAKey.RSAKey}
@return: An RSA key.
@raise SyntaxError: If the key is not properly formatted.
"""
for implementation in implementations:
if implementation == "python":
key = Python_RSAKey.parseXML(s)
break
else:
raise ValueError("No acceptable implementations")
return _parseKeyHelper(key, private, public)
#Parse as an OpenSSL or Python key
def parsePEMKey(s, private=False, public=False, passwordCallback=None,
implementations=["openssl", "python"]):
"""Parse a PEM-format key.
The PEM format is used by OpenSSL and other tools. The
format is typically used to store both the public and private
components of a key. For example::
-----BEGIN RSA PRIVATE KEY-----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-----END RSA PRIVATE KEY-----
To generate a key like this with OpenSSL, run::
openssl genrsa 2048 > key.pem
This format also supports password-encrypted private keys. TLS
Lite can only handle password-encrypted private keys when OpenSSL
and M2Crypto are installed. In this case, passwordCallback will be
invoked to query the user for the password.
@type s: str
@param s: A string containing a PEM-encoded public or private key.
@type private: bool
@param private: If True, a L{SyntaxError} will be raised if the
private key component is not present.
@type public: bool
@param public: If True, the private key component (if present) will
be discarded, so this function will always return a public key.
@type passwordCallback: callable
@param passwordCallback: This function will be called, with no
arguments, if the PEM-encoded private key is password-encrypted.
The callback should return the password string. If the password is
incorrect, SyntaxError will be raised. If no callback is passed
and the key is password-encrypted, a prompt will be displayed at
the console.
@rtype: L{tlslite.utils.RSAKey.RSAKey}
@return: An RSA key.
@raise SyntaxError: If the key is not properly formatted.
"""
for implementation in implementations:
if implementation == "openssl" and cryptomath.m2cryptoLoaded:
key = OpenSSL_RSAKey.parse(s, passwordCallback)
break
elif implementation == "python":
key = Python_RSAKey.parsePEM(s)
break
else:
raise ValueError("No acceptable implementations")
return _parseKeyHelper(key, private, public)
def _parseKeyHelper(key, private, public):
if private:
if not key.hasPrivateKey():
raise SyntaxError("Not a private key!")
if public:
return _createPublicKey(key)
if private:
if hasattr(key, "d"):
return _createPrivateKey(key)
else:
return key
return key
def parseAsPublicKey(s):
"""Parse an XML or PEM-formatted public key.
@type s: str
@param s: A string containing an XML or PEM-encoded public or private key.
@rtype: L{tlslite.utils.RSAKey.RSAKey}
@return: An RSA public key.
@raise SyntaxError: If the key is not properly formatted.
"""
try:
return parsePEMKey(s, public=True)
except:
return parseXMLKey(s, public=True)
def parsePrivateKey(s):
"""Parse an XML or PEM-formatted private key.
@type s: str
@param s: A string containing an XML or PEM-encoded private key.
@rtype: L{tlslite.utils.RSAKey.RSAKey}
@return: An RSA private key.
@raise SyntaxError: If the key is not properly formatted.
"""
try:
return parsePEMKey(s, private=True)
except:
return parseXMLKey(s, private=True)
def _createPublicKey(key):
"""
Create a new public key. Discard any private component,
and return the most efficient key possible.
"""
if not isinstance(key, RSAKey):
raise AssertionError()
return _createPublicRSAKey(key.n, key.e)
def _createPrivateKey(key):
"""
Create a new private key. Return the most efficient key possible.
"""
if not isinstance(key, RSAKey):
raise AssertionError()
if not key.hasPrivateKey():
raise AssertionError()
return _createPrivateRSAKey(key.n, key.e, key.d, key.p, key.q, key.dP,
key.dQ, key.qInv)
def _createPublicRSAKey(n, e, implementations = ["openssl", "pycrypto",
"python"]):
for implementation in implementations:
if implementation == "openssl" and cryptomath.m2cryptoLoaded:
return OpenSSL_RSAKey(n, e)
elif implementation == "pycrypto" and cryptomath.pycryptoLoaded:
return PyCrypto_RSAKey(n, e)
elif implementation == "python":
return Python_RSAKey(n, e)
raise ValueError("No acceptable implementations")
def _createPrivateRSAKey(n, e, d, p, q, dP, dQ, qInv,
implementations = ["pycrypto", "python"]):
for implementation in implementations:
if implementation == "pycrypto" and cryptomath.pycryptoLoaded:
return PyCrypto_RSAKey(n, e, d, p, q, dP, dQ, qInv)
elif implementation == "python":
return Python_RSAKey(n, e, d, p, q, dP, dQ, qInv)
raise ValueError("No acceptable implementations")