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diff --git a/frozen_deps/Crypto/PublicKey/RSA.py b/frozen_deps/Crypto/PublicKey/RSA.py new file mode 100644 index 0000000..debe39e --- /dev/null +++ b/frozen_deps/Crypto/PublicKey/RSA.py @@ -0,0 +1,719 @@ +# -*- coding: utf-8 -*- +# +# PublicKey/RSA.py : RSA public key primitive +# +# Written in 2008 by Dwayne C. Litzenberger <dlitz@dlitz.net> +# +# =================================================================== +# The contents of this file are dedicated to the public domain. To +# the extent that dedication to the public domain is not available, +# everyone is granted a worldwide, perpetual, royalty-free, +# non-exclusive license to exercise all rights associated with the +# contents of this file for any purpose whatsoever. +# No rights are reserved. +# +# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, +# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF +# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND +# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS +# BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN +# ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN +# CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE +# SOFTWARE. +# =================================================================== + +"""RSA public-key cryptography algorithm (signature and encryption). + +RSA_ is the most widespread and used public key algorithm. Its security is +based on the difficulty of factoring large integers. The algorithm has +withstood attacks for 30 years, and it is therefore considered reasonably +secure for new designs. + +The algorithm can be used for both confidentiality (encryption) and +authentication (digital signature). It is worth noting that signing and +decryption are significantly slower than verification and encryption. +The cryptograhic strength is primarily linked to the length of the modulus *n*. +In 2012, a sufficient length is deemed to be 2048 bits. For more information, +see the most recent ECRYPT_ report. + +Both RSA ciphertext and RSA signature are as big as the modulus *n* (256 +bytes if *n* is 2048 bit long). + +This module provides facilities for generating fresh, new RSA keys, constructing +them from known components, exporting them, and importing them. + + >>> from Crypto.PublicKey import RSA + >>> + >>> key = RSA.generate(2048) + >>> f = open('mykey.pem','w') + >>> f.write(RSA.exportKey('PEM')) + >>> f.close() + ... + >>> f = open('mykey.pem','r') + >>> key = RSA.importKey(f.read()) + +Even though you may choose to directly use the methods of an RSA key object +to perform the primitive cryptographic operations (e.g. `_RSAobj.encrypt`), +it is recommended to use one of the standardized schemes instead (like +`Crypto.Cipher.PKCS1_v1_5` or `Crypto.Signature.PKCS1_v1_5`). + +.. _RSA: http://en.wikipedia.org/wiki/RSA_%28algorithm%29 +.. _ECRYPT: http://www.ecrypt.eu.org/documents/D.SPA.17.pdf + +:sort: generate,construct,importKey,error +""" + +__revision__ = "$Id$" + +__all__ = ['generate', 'construct', 'error', 'importKey', 'RSAImplementation', '_RSAobj'] + +import sys +if sys.version_info[0] == 2 and sys.version_info[1] == 1: + from Crypto.Util.py21compat import * +from Crypto.Util.py3compat import * +#from Crypto.Util.python_compat import * +from Crypto.Util.number import getRandomRange, bytes_to_long, long_to_bytes + +from Crypto.PublicKey import _RSA, _slowmath, pubkey +from Crypto import Random + +from Crypto.Util.asn1 import DerObject, DerSequence, DerNull +import binascii +import struct + +from Crypto.Util.number import inverse + +from Crypto.Util.number import inverse + +try: + from Crypto.PublicKey import _fastmath +except ImportError: + _fastmath = None + +class _RSAobj(pubkey.pubkey): + """Class defining an actual RSA key. + + :undocumented: __getstate__, __setstate__, __repr__, __getattr__ + """ + #: Dictionary of RSA parameters. + #: + #: A public key will only have the following entries: + #: + #: - **n**, the modulus. + #: - **e**, the public exponent. + #: + #: A private key will also have: + #: + #: - **d**, the private exponent. + #: - **p**, the first factor of n. + #: - **q**, the second factor of n. + #: - **u**, the CRT coefficient (1/p) mod q. + keydata = ['n', 'e', 'd', 'p', 'q', 'u'] + + def __init__(self, implementation, key, randfunc=None): + self.implementation = implementation + self.key = key + if randfunc is None: + randfunc = Random.new().read + self._randfunc = randfunc + + def __getattr__(self, attrname): + if attrname in self.keydata: + # For backward compatibility, allow the user to get (not set) the + # RSA key parameters directly from this object. + return getattr(self.key, attrname) + else: + raise AttributeError("%s object has no %r attribute" % (self.__class__.__name__, attrname,)) + + def encrypt(self, plaintext, K): + """Encrypt a piece of data with RSA. + + :Parameter plaintext: The piece of data to encrypt with RSA. It may not + be numerically larger than the RSA module (**n**). + :Type plaintext: byte string or long + + :Parameter K: A random parameter (*for compatibility only. This + value will be ignored*) + :Type K: byte string or long + + :attention: this function performs the plain, primitive RSA encryption + (*textbook*). In real applications, you always need to use proper + cryptographic padding, and you should not directly encrypt data with + this method. Failure to do so may lead to security vulnerabilities. + It is recommended to use modules + `Crypto.Cipher.PKCS1_OAEP` or `Crypto.Cipher.PKCS1_v1_5` instead. + + :Return: A tuple with two items. The first item is the ciphertext + of the same type as the plaintext (string or long). The second item + is always None. + """ + return pubkey.pubkey.encrypt(self, plaintext, K) + + def decrypt(self, ciphertext): + """Decrypt a piece of data with RSA. + + Decryption always takes place with blinding. + + :attention: this function performs the plain, primitive RSA decryption + (*textbook*). In real applications, you always need to use proper + cryptographic padding, and you should not directly decrypt data with + this method. Failure to do so may lead to security vulnerabilities. + It is recommended to use modules + `Crypto.Cipher.PKCS1_OAEP` or `Crypto.Cipher.PKCS1_v1_5` instead. + + :Parameter ciphertext: The piece of data to decrypt with RSA. It may + not be numerically larger than the RSA module (**n**). If a tuple, + the first item is the actual ciphertext; the second item is ignored. + + :Type ciphertext: byte string, long or a 2-item tuple as returned by + `encrypt` + + :Return: A byte string if ciphertext was a byte string or a tuple + of byte strings. A long otherwise. + """ + return pubkey.pubkey.decrypt(self, ciphertext) + + def sign(self, M, K): + """Sign a piece of data with RSA. + + Signing always takes place with blinding. + + :attention: this function performs the plain, primitive RSA decryption + (*textbook*). In real applications, you always need to use proper + cryptographic padding, and you should not directly sign data with + this method. Failure to do so may lead to security vulnerabilities. + It is recommended to use modules + `Crypto.Signature.PKCS1_PSS` or `Crypto.Signature.PKCS1_v1_5` instead. + + :Parameter M: The piece of data to sign with RSA. It may + not be numerically larger than the RSA module (**n**). + :Type M: byte string or long + + :Parameter K: A random parameter (*for compatibility only. This + value will be ignored*) + :Type K: byte string or long + + :Return: A 2-item tuple. The first item is the actual signature (a + long). The second item is always None. + """ + return pubkey.pubkey.sign(self, M, K) + + def verify(self, M, signature): + """Verify the validity of an RSA signature. + + :attention: this function performs the plain, primitive RSA encryption + (*textbook*). In real applications, you always need to use proper + cryptographic padding, and you should not directly verify data with + this method. Failure to do so may lead to security vulnerabilities. + It is recommended to use modules + `Crypto.Signature.PKCS1_PSS` or `Crypto.Signature.PKCS1_v1_5` instead. + + :Parameter M: The expected message. + :Type M: byte string or long + + :Parameter signature: The RSA signature to verify. The first item of + the tuple is the actual signature (a long not larger than the modulus + **n**), whereas the second item is always ignored. + :Type signature: A 2-item tuple as return by `sign` + + :Return: True if the signature is correct, False otherwise. + """ + return pubkey.pubkey.verify(self, M, signature) + + def _encrypt(self, c, K): + return (self.key._encrypt(c),) + + def _decrypt(self, c): + #(ciphertext,) = c + (ciphertext,) = c[:1] # HACK - We should use the previous line + # instead, but this is more compatible and we're + # going to replace the Crypto.PublicKey API soon + # anyway. + + # Blinded RSA decryption (to prevent timing attacks): + # Step 1: Generate random secret blinding factor r, such that 0 < r < n-1 + r = getRandomRange(1, self.key.n-1, randfunc=self._randfunc) + # Step 2: Compute c' = c * r**e mod n + cp = self.key._blind(ciphertext, r) + # Step 3: Compute m' = c'**d mod n (ordinary RSA decryption) + mp = self.key._decrypt(cp) + # Step 4: Compute m = m**(r-1) mod n + return self.key._unblind(mp, r) + + def _blind(self, m, r): + return self.key._blind(m, r) + + def _unblind(self, m, r): + return self.key._unblind(m, r) + + def _sign(self, m, K=None): + return (self.key._sign(m),) + + def _verify(self, m, sig): + #(s,) = sig + (s,) = sig[:1] # HACK - We should use the previous line instead, but + # this is more compatible and we're going to replace + # the Crypto.PublicKey API soon anyway. + return self.key._verify(m, s) + + def has_private(self): + return self.key.has_private() + + def size(self): + return self.key.size() + + def can_blind(self): + return True + + def can_encrypt(self): + return True + + def can_sign(self): + return True + + def publickey(self): + return self.implementation.construct((self.key.n, self.key.e)) + + def __getstate__(self): + d = {} + for k in self.keydata: + try: + d[k] = getattr(self.key, k) + except AttributeError: + pass + return d + + def __setstate__(self, d): + if not hasattr(self, 'implementation'): + self.implementation = RSAImplementation() + t = [] + for k in self.keydata: + if k not in d: + break + t.append(d[k]) + self.key = self.implementation._math.rsa_construct(*tuple(t)) + + def __repr__(self): + attrs = [] + for k in self.keydata: + if k == 'n': + attrs.append("n(%d)" % (self.size()+1,)) + elif hasattr(self.key, k): + attrs.append(k) + if self.has_private(): + attrs.append("private") + # PY3K: This is meant to be text, do not change to bytes (data) + return "<%s @0x%x %s>" % (self.__class__.__name__, id(self), ",".join(attrs)) + + def exportKey(self, format='PEM', passphrase=None, pkcs=1): + """Export this RSA key. + + :Parameter format: The format to use for wrapping the key. + + - *'DER'*. Binary encoding, always unencrypted. + - *'PEM'*. Textual encoding, done according to `RFC1421`_/`RFC1423`_. + Unencrypted (default) or encrypted. + - *'OpenSSH'*. Textual encoding, done according to OpenSSH specification. + Only suitable for public keys (not private keys). + :Type format: string + + :Parameter passphrase: In case of PEM, the pass phrase to derive the encryption key from. + :Type passphrase: string + + :Parameter pkcs: The PKCS standard to follow for assembling the key. + You have two choices: + + - with **1**, the public key is embedded into an X.509 `SubjectPublicKeyInfo` DER SEQUENCE. + The private key is embedded into a `PKCS#1`_ `RSAPrivateKey` DER SEQUENCE. + This mode is the default. + - with **8**, the private key is embedded into a `PKCS#8`_ `PrivateKeyInfo` DER SEQUENCE. + This mode is not available for public keys. + + PKCS standards are not relevant for the *OpenSSH* format. + :Type pkcs: integer + + :Return: A byte string with the encoded public or private half. + :Raise ValueError: + When the format is unknown. + + .. _RFC1421: http://www.ietf.org/rfc/rfc1421.txt + .. _RFC1423: http://www.ietf.org/rfc/rfc1423.txt + .. _`PKCS#1`: http://www.ietf.org/rfc/rfc3447.txt + .. _`PKCS#8`: http://www.ietf.org/rfc/rfc5208.txt + """ + if passphrase is not None: + passphrase = tobytes(passphrase) + if format=='OpenSSH': + eb = long_to_bytes(self.e) + nb = long_to_bytes(self.n) + if bord(eb[0]) & 0x80: eb=bchr(0x00)+eb + if bord(nb[0]) & 0x80: nb=bchr(0x00)+nb + keyparts = [ 'ssh-rsa', eb, nb ] + keystring = ''.join([ struct.pack(">I",len(kp))+kp for kp in keyparts]) + return 'ssh-rsa '+binascii.b2a_base64(keystring)[:-1] + + # DER format is always used, even in case of PEM, which simply + # encodes it into BASE64. + der = DerSequence() + if self.has_private(): + keyType= { 1: 'RSA PRIVATE', 8: 'PRIVATE' }[pkcs] + der[:] = [ 0, self.n, self.e, self.d, self.p, self.q, + self.d % (self.p-1), self.d % (self.q-1), + inverse(self.q, self.p) ] + if pkcs==8: + derkey = der.encode() + der = DerSequence([0]) + der.append(algorithmIdentifier) + der.append(DerObject('OCTET STRING', derkey).encode()) + else: + keyType = "PUBLIC" + der.append(algorithmIdentifier) + bitmap = DerObject('BIT STRING') + derPK = DerSequence( [ self.n, self.e ] ) + bitmap.payload = bchr(0x00) + derPK.encode() + der.append(bitmap.encode()) + if format=='DER': + return der.encode() + if format=='PEM': + pem = b("-----BEGIN " + keyType + " KEY-----\n") + objenc = None + if passphrase and keyType.endswith('PRIVATE'): + # We only support 3DES for encryption + import Crypto.Hash.MD5 + from Crypto.Cipher import DES3 + from Crypto.Protocol.KDF import PBKDF1 + salt = self._randfunc(8) + key = PBKDF1(passphrase, salt, 16, 1, Crypto.Hash.MD5) + key += PBKDF1(key+passphrase, salt, 8, 1, Crypto.Hash.MD5) + objenc = DES3.new(key, Crypto.Cipher.DES3.MODE_CBC, salt) + pem += b('Proc-Type: 4,ENCRYPTED\n') + pem += b('DEK-Info: DES-EDE3-CBC,') + binascii.b2a_hex(salt).upper() + b('\n\n') + + binaryKey = der.encode() + if objenc: + # Add PKCS#7-like padding + padding = objenc.block_size-len(binaryKey)%objenc.block_size + binaryKey = objenc.encrypt(binaryKey+bchr(padding)*padding) + + # Each BASE64 line can take up to 64 characters (=48 bytes of data) + chunks = [ binascii.b2a_base64(binaryKey[i:i+48]) for i in range(0, len(binaryKey), 48) ] + pem += b('').join(chunks) + pem += b("-----END " + keyType + " KEY-----") + return pem + return ValueError("Unknown key format '%s'. Cannot export the RSA key." % format) + +class RSAImplementation(object): + """ + An RSA key factory. + + This class is only internally used to implement the methods of the `Crypto.PublicKey.RSA` module. + + :sort: __init__,generate,construct,importKey + :undocumented: _g*, _i* + """ + + def __init__(self, **kwargs): + """Create a new RSA key factory. + + :Keywords: + use_fast_math : bool + Specify which mathematic library to use: + + - *None* (default). Use fastest math available. + - *True* . Use fast math. + - *False* . Use slow math. + default_randfunc : callable + Specify how to collect random data: + + - *None* (default). Use Random.new().read(). + - not *None* . Use the specified function directly. + :Raise RuntimeError: + When **use_fast_math** =True but fast math is not available. + """ + use_fast_math = kwargs.get('use_fast_math', None) + if use_fast_math is None: # Automatic + if _fastmath is not None: + self._math = _fastmath + else: + self._math = _slowmath + + elif use_fast_math: # Explicitly select fast math + if _fastmath is not None: + self._math = _fastmath + else: + raise RuntimeError("fast math module not available") + + else: # Explicitly select slow math + self._math = _slowmath + + self.error = self._math.error + + self._default_randfunc = kwargs.get('default_randfunc', None) + self._current_randfunc = None + + def _get_randfunc(self, randfunc): + if randfunc is not None: + return randfunc + elif self._current_randfunc is None: + self._current_randfunc = Random.new().read + return self._current_randfunc + + def generate(self, bits, randfunc=None, progress_func=None, e=65537): + """Randomly generate a fresh, new RSA key. + + :Parameters: + bits : int + Key length, or size (in bits) of the RSA modulus. + It must be a multiple of 256, and no smaller than 1024. + + randfunc : callable + Random number generation function; it should accept + a single integer N and return a string of random data + N bytes long. + If not specified, a new one will be instantiated + from ``Crypto.Random``. + + progress_func : callable + Optional function that will be called with a short string + containing the key parameter currently being generated; + it's useful for interactive applications where a user is + waiting for a key to be generated. + + e : int + Public RSA exponent. It must be an odd positive integer. + It is typically a small number with very few ones in its + binary representation. + The default value 65537 (= ``0b10000000000000001`` ) is a safe + choice: other common values are 5, 7, 17, and 257. + + :attention: You should always use a cryptographically secure random number generator, + such as the one defined in the ``Crypto.Random`` module; **don't** just use the + current time and the ``random`` module. + + :attention: Exponent 3 is also widely used, but it requires very special care when padding + the message. + + :Return: An RSA key object (`_RSAobj`). + + :Raise ValueError: + When **bits** is too little or not a multiple of 256, or when + **e** is not odd or smaller than 2. + """ + if bits < 1024 or (bits & 0xff) != 0: + # pubkey.getStrongPrime doesn't like anything that's not a multiple of 256 and >= 1024 + raise ValueError("RSA modulus length must be a multiple of 256 and >= 1024") + if e%2==0 or e<3: + raise ValueError("RSA public exponent must be a positive, odd integer larger than 2.") + rf = self._get_randfunc(randfunc) + obj = _RSA.generate_py(bits, rf, progress_func, e) # TODO: Don't use legacy _RSA module + key = self._math.rsa_construct(obj.n, obj.e, obj.d, obj.p, obj.q, obj.u) + return _RSAobj(self, key) + + def construct(self, tup): + """Construct an RSA key from a tuple of valid RSA components. + + The modulus **n** must be the product of two primes. + The public exponent **e** must be odd and larger than 1. + + In case of a private key, the following equations must apply: + + - e != 1 + - p*q = n + - e*d = 1 mod (p-1)(q-1) + - p*u = 1 mod q + + :Parameters: + tup : tuple + A tuple of long integers, with at least 2 and no + more than 6 items. The items come in the following order: + + 1. RSA modulus (n). + 2. Public exponent (e). + 3. Private exponent (d). Only required if the key is private. + 4. First factor of n (p). Optional. + 5. Second factor of n (q). Optional. + 6. CRT coefficient, (1/p) mod q (u). Optional. + + :Return: An RSA key object (`_RSAobj`). + """ + key = self._math.rsa_construct(*tup) + return _RSAobj(self, key) + + def _importKeyDER(self, externKey): + """Import an RSA key (public or private half), encoded in DER form.""" + + try: + + der = DerSequence() + der.decode(externKey, True) + + # Try PKCS#1 first, for a private key + if len(der)==9 and der.hasOnlyInts() and der[0]==0: + # ASN.1 RSAPrivateKey element + del der[6:] # Remove d mod (p-1), d mod (q-1), and q^{-1} mod p + der.append(inverse(der[4],der[5])) # Add p^{-1} mod q + del der[0] # Remove version + return self.construct(der[:]) + + # Keep on trying PKCS#1, but now for a public key + if len(der)==2: + # The DER object is an RSAPublicKey SEQUENCE with two elements + if der.hasOnlyInts(): + return self.construct(der[:]) + # The DER object is a SubjectPublicKeyInfo SEQUENCE with two elements: + # an 'algorithm' (or 'algorithmIdentifier') SEQUENCE and a 'subjectPublicKey' BIT STRING. + # 'algorithm' takes the value given a few lines above. + # 'subjectPublicKey' encapsulates the actual ASN.1 RSAPublicKey element. + if der[0]==algorithmIdentifier: + bitmap = DerObject() + bitmap.decode(der[1], True) + if bitmap.isType('BIT STRING') and bord(bitmap.payload[0])==0x00: + der.decode(bitmap.payload[1:], True) + if len(der)==2 and der.hasOnlyInts(): + return self.construct(der[:]) + + # Try unencrypted PKCS#8 + if der[0]==0: + # The second element in the SEQUENCE is algorithmIdentifier. + # It must say RSA (see above for description). + if der[1]==algorithmIdentifier: + privateKey = DerObject() + privateKey.decode(der[2], True) + if privateKey.isType('OCTET STRING'): + return self._importKeyDER(privateKey.payload) + + except ValueError as IndexError: + pass + + raise ValueError("RSA key format is not supported") + + def importKey(self, externKey, passphrase=None): + """Import an RSA key (public or private half), encoded in standard form. + + :Parameter externKey: + The RSA key to import, encoded as a string. + + An RSA public key can be in any of the following formats: + + - X.509 `subjectPublicKeyInfo` DER SEQUENCE (binary or PEM encoding) + - `PKCS#1`_ `RSAPublicKey` DER SEQUENCE (binary or PEM encoding) + - OpenSSH (textual public key only) + + An RSA private key can be in any of the following formats: + + - PKCS#1 `RSAPrivateKey` DER SEQUENCE (binary or PEM encoding) + - `PKCS#8`_ `PrivateKeyInfo` DER SEQUENCE (binary or PEM encoding) + - OpenSSH (textual public key only) + + For details about the PEM encoding, see `RFC1421`_/`RFC1423`_. + + In case of PEM encoding, the private key can be encrypted with DES or 3TDES according to a certain ``pass phrase``. + Only OpenSSL-compatible pass phrases are supported. + :Type externKey: string + + :Parameter passphrase: + In case of an encrypted PEM key, this is the pass phrase from which the encryption key is derived. + :Type passphrase: string + + :Return: An RSA key object (`_RSAobj`). + + :Raise ValueError/IndexError/TypeError: + When the given key cannot be parsed (possibly because the pass phrase is wrong). + + .. _RFC1421: http://www.ietf.org/rfc/rfc1421.txt + .. _RFC1423: http://www.ietf.org/rfc/rfc1423.txt + .. _`PKCS#1`: http://www.ietf.org/rfc/rfc3447.txt + .. _`PKCS#8`: http://www.ietf.org/rfc/rfc5208.txt + """ + externKey = tobytes(externKey) + if passphrase is not None: + passphrase = tobytes(passphrase) + + if externKey.startswith(b('-----')): + # This is probably a PEM encoded key + lines = externKey.replace(b(" "),b('')).split() + keyobj = None + + # The encrypted PEM format + if lines[1].startswith(b('Proc-Type:4,ENCRYPTED')): + DEK = lines[2].split(b(':')) + if len(DEK)!=2 or DEK[0]!=b('DEK-Info') or not passphrase: + raise ValueError("PEM encryption format not supported.") + algo, salt = DEK[1].split(b(',')) + salt = binascii.a2b_hex(salt) + import Crypto.Hash.MD5 + from Crypto.Cipher import DES, DES3 + from Crypto.Protocol.KDF import PBKDF1 + if algo==b("DES-CBC"): + # This is EVP_BytesToKey in OpenSSL + key = PBKDF1(passphrase, salt, 8, 1, Crypto.Hash.MD5) + keyobj = DES.new(key, Crypto.Cipher.DES.MODE_CBC, salt) + elif algo==b("DES-EDE3-CBC"): + # Note that EVP_BytesToKey is note exactly the same as PBKDF1 + key = PBKDF1(passphrase, salt, 16, 1, Crypto.Hash.MD5) + key += PBKDF1(key+passphrase, salt, 8, 1, Crypto.Hash.MD5) + keyobj = DES3.new(key, Crypto.Cipher.DES3.MODE_CBC, salt) + else: + raise ValueError("Unsupport PEM encryption algorithm.") + lines = lines[2:] + + der = binascii.a2b_base64(b('').join(lines[1:-1])) + if keyobj: + der = keyobj.decrypt(der) + padding = bord(der[-1]) + der = der[:-padding] + return self._importKeyDER(der) + + if externKey.startswith(b('ssh-rsa ')): + # This is probably an OpenSSH key + keystring = binascii.a2b_base64(externKey.split(b(' '))[1]) + keyparts = [] + while len(keystring)>4: + l = struct.unpack(">I",keystring[:4])[0] + keyparts.append(keystring[4:4+l]) + keystring = keystring[4+l:] + e = bytes_to_long(keyparts[1]) + n = bytes_to_long(keyparts[2]) + return self.construct([n, e]) + if bord(externKey[0])==0x30: + # This is probably a DER encoded key + return self._importKeyDER(externKey) + + raise ValueError("RSA key format is not supported") + +#: This is the ASN.1 DER object that qualifies an algorithm as +#: compliant to PKCS#1 (that is, the standard RSA). +# It is found in all 'algorithm' fields (also called 'algorithmIdentifier'). +# It is a SEQUENCE with the oid assigned to RSA and with its parameters (none). +# 0x06 0x09 OBJECT IDENTIFIER, 9 bytes of payload +# 0x2A 0x86 0x48 0x86 0xF7 0x0D 0x01 0x01 0x01 +# rsaEncryption (1 2 840 113549 1 1 1) (PKCS #1) +# 0x05 0x00 NULL +algorithmIdentifier = DerSequence( + [ b('\x06\x09\x2A\x86\x48\x86\xF7\x0D\x01\x01\x01'), + DerNull().encode() ] + ).encode() + +_impl = RSAImplementation() +#: +#: Randomly generate a fresh, new RSA key object. +#: +#: See `RSAImplementation.generate`. +#: +generate = _impl.generate +#: +#: Construct an RSA key object from a tuple of valid RSA components. +#: +#: See `RSAImplementation.construct`. +#: +construct = _impl.construct +#: +#: Import an RSA key (public or private half), encoded in standard form. +#: +#: See `RSAImplementation.importKey`. +#: +importKey = _impl.importKey +error = _impl.error + +# vim:set ts=4 sw=4 sts=4 expandtab: + |