From c4d90bf4ea0c5b7a016028ed994de19638d3113b Mon Sep 17 00:00:00 2001 From: Determinant Date: Tue, 17 Nov 2020 20:04:09 -0500 Subject: support saving as a keystore file --- frozen_deps/Cryptodome/PublicKey/RSA.py | 796 ++++++++++++++++++++++++++++++++ 1 file changed, 796 insertions(+) create mode 100644 frozen_deps/Cryptodome/PublicKey/RSA.py (limited to 'frozen_deps/Cryptodome/PublicKey/RSA.py') diff --git a/frozen_deps/Cryptodome/PublicKey/RSA.py b/frozen_deps/Cryptodome/PublicKey/RSA.py new file mode 100644 index 0000000..27331ca --- /dev/null +++ b/frozen_deps/Cryptodome/PublicKey/RSA.py @@ -0,0 +1,796 @@ +# -*- coding: utf-8 -*- +# =================================================================== +# +# Copyright (c) 2016, Legrandin +# All rights reserved. +# +# Redistribution and use in source and binary forms, with or without +# modification, are permitted provided that the following conditions +# are met: +# +# 1. Redistributions of source code must retain the above copyright +# notice, this list of conditions and the following disclaimer. +# 2. Redistributions in binary form must reproduce the above copyright +# notice, this list of conditions and the following disclaimer in +# the documentation and/or other materials provided with the +# distribution. +# +# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS +# FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE +# COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, +# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, +# BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; +# LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER +# CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN +# ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE +# POSSIBILITY OF SUCH DAMAGE. +# =================================================================== + +__all__ = ['generate', 'construct', 'import_key', + 'RsaKey', 'oid'] + +import binascii +import struct + +from Cryptodome import Random +from Cryptodome.Util.py3compat import tobytes, bord, tostr +from Cryptodome.Util.asn1 import DerSequence + +from Cryptodome.Math.Numbers import Integer +from Cryptodome.Math.Primality import (test_probable_prime, + generate_probable_prime, COMPOSITE) + +from Cryptodome.PublicKey import (_expand_subject_public_key_info, + _create_subject_public_key_info, + _extract_subject_public_key_info) + + +class RsaKey(object): + r"""Class defining an actual RSA key. + Do not instantiate directly. + Use :func:`generate`, :func:`construct` or :func:`import_key` instead. + + :ivar n: RSA modulus + :vartype n: integer + + :ivar e: RSA public exponent + :vartype e: integer + + :ivar d: RSA private exponent + :vartype d: integer + + :ivar p: First factor of the RSA modulus + :vartype p: integer + + :ivar q: Second factor of the RSA modulus + :vartype q: integer + + :ivar u: Chinese remainder component (:math:`p^{-1} \text{mod } q`) + :vartype q: integer + """ + + def __init__(self, **kwargs): + """Build an RSA key. + + :Keywords: + n : integer + The modulus. + e : integer + The public exponent. + d : integer + The private exponent. Only required for private keys. + p : integer + The first factor of the modulus. Only required for private keys. + q : integer + The second factor of the modulus. Only required for private keys. + u : integer + The CRT coefficient (inverse of p modulo q). Only required for + private keys. + """ + + input_set = set(kwargs.keys()) + public_set = set(('n', 'e')) + private_set = public_set | set(('p', 'q', 'd', 'u')) + if input_set not in (private_set, public_set): + raise ValueError("Some RSA components are missing") + for component, value in kwargs.items(): + setattr(self, "_" + component, value) + if input_set == private_set: + self._dp = self._d % (self._p - 1) # = (e⁻¹) mod (p-1) + self._dq = self._d % (self._q - 1) # = (e⁻¹) mod (q-1) + + @property + def n(self): + return int(self._n) + + @property + def e(self): + return int(self._e) + + @property + def d(self): + if not self.has_private(): + raise AttributeError("No private exponent available for public keys") + return int(self._d) + + @property + def p(self): + if not self.has_private(): + raise AttributeError("No CRT component 'p' available for public keys") + return int(self._p) + + @property + def q(self): + if not self.has_private(): + raise AttributeError("No CRT component 'q' available for public keys") + return int(self._q) + + @property + def u(self): + if not self.has_private(): + raise AttributeError("No CRT component 'u' available for public keys") + return int(self._u) + + def size_in_bits(self): + """Size of the RSA modulus in bits""" + return self._n.size_in_bits() + + def size_in_bytes(self): + """The minimal amount of bytes that can hold the RSA modulus""" + return (self._n.size_in_bits() - 1) // 8 + 1 + + def _encrypt(self, plaintext): + if not 0 <= plaintext < self._n: + raise ValueError("Plaintext too large") + return int(pow(Integer(plaintext), self._e, self._n)) + + def _decrypt(self, ciphertext): + if not 0 <= ciphertext < self._n: + raise ValueError("Ciphertext too large") + if not self.has_private(): + raise TypeError("This is not a private key") + + # Blinded RSA decryption (to prevent timing attacks): + # Step 1: Generate random secret blinding factor r, + # such that 0 < r < n-1 + r = Integer.random_range(min_inclusive=1, max_exclusive=self._n) + # Step 2: Compute c' = c * r**e mod n + cp = Integer(ciphertext) * pow(r, self._e, self._n) % self._n + # Step 3: Compute m' = c'**d mod n (normal RSA decryption) + m1 = pow(cp, self._dp, self._p) + m2 = pow(cp, self._dq, self._q) + h = ((m2 - m1) * self._u) % self._q + mp = h * self._p + m1 + # Step 4: Compute m = m**(r-1) mod n + result = (r.inverse(self._n) * mp) % self._n + # Verify no faults occurred + if ciphertext != pow(result, self._e, self._n): + raise ValueError("Fault detected in RSA decryption") + return result + + def has_private(self): + """Whether this is an RSA private key""" + + return hasattr(self, "_d") + + def can_encrypt(self): # legacy + return True + + def can_sign(self): # legacy + return True + + def publickey(self): + """A matching RSA public key. + + Returns: + a new :class:`RsaKey` object + """ + return RsaKey(n=self._n, e=self._e) + + def __eq__(self, other): + if self.has_private() != other.has_private(): + return False + if self.n != other.n or self.e != other.e: + return False + if not self.has_private(): + return True + return (self.d == other.d) + + def __ne__(self, other): + return not (self == other) + + def __getstate__(self): + # RSA key is not pickable + from pickle import PicklingError + raise PicklingError + + def __repr__(self): + if self.has_private(): + extra = ", d=%d, p=%d, q=%d, u=%d" % (int(self._d), int(self._p), + int(self._q), int(self._u)) + else: + extra = "" + return "RsaKey(n=%d, e=%d%s)" % (int(self._n), int(self._e), extra) + + def __str__(self): + if self.has_private(): + key_type = "Private" + else: + key_type = "Public" + return "%s RSA key at 0x%X" % (key_type, id(self)) + + def export_key(self, format='PEM', passphrase=None, pkcs=1, + protection=None, randfunc=None): + """Export this RSA key. + + Args: + format (string): + The format to use for wrapping the key: + + - *'PEM'*. (*Default*) Text encoding, done according to `RFC1421`_/`RFC1423`_. + - *'DER'*. Binary encoding. + - *'OpenSSH'*. Textual encoding, done according to OpenSSH specification. + Only suitable for public keys (not private keys). + + passphrase (string): + (*For private keys only*) The pass phrase used for protecting the output. + + pkcs (integer): + (*For private keys only*) The ASN.1 structure to use for + serializing the key. Note that even in case of PEM + encoding, there is an inner ASN.1 DER structure. + + With ``pkcs=1`` (*default*), the private key is encoded in a + simple `PKCS#1`_ structure (``RSAPrivateKey``). + + With ``pkcs=8``, the private key is encoded in a `PKCS#8`_ structure + (``PrivateKeyInfo``). + + .. note:: + This parameter is ignored for a public key. + For DER and PEM, an ASN.1 DER ``SubjectPublicKeyInfo`` + structure is always used. + + protection (string): + (*For private keys only*) + The encryption scheme to use for protecting the private key. + + If ``None`` (default), the behavior depends on :attr:`format`: + + - For *'DER'*, the *PBKDF2WithHMAC-SHA1AndDES-EDE3-CBC* + scheme is used. The following operations are performed: + + 1. A 16 byte Triple DES key is derived from the passphrase + using :func:`Cryptodome.Protocol.KDF.PBKDF2` with 8 bytes salt, + and 1 000 iterations of :mod:`Cryptodome.Hash.HMAC`. + 2. The private key is encrypted using CBC. + 3. The encrypted key is encoded according to PKCS#8. + + - For *'PEM'*, the obsolete PEM encryption scheme is used. + It is based on MD5 for key derivation, and Triple DES for encryption. + + Specifying a value for :attr:`protection` is only meaningful for PKCS#8 + (that is, ``pkcs=8``) and only if a pass phrase is present too. + + The supported schemes for PKCS#8 are listed in the + :mod:`Cryptodome.IO.PKCS8` module (see :attr:`wrap_algo` parameter). + + randfunc (callable): + A function that provides random bytes. Only used for PEM encoding. + The default is :func:`Cryptodome.Random.get_random_bytes`. + + Returns: + byte string: the encoded key + + Raises: + ValueError:when the format is unknown or when you try to encrypt a private + key with *DER* format and PKCS#1. + + .. warning:: + If you don't provide a pass phrase, the private key will be + exported in the clear! + + .. _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 randfunc is None: + randfunc = Random.get_random_bytes + + if format == 'OpenSSH': + e_bytes, n_bytes = [x.to_bytes() for x in (self._e, self._n)] + if bord(e_bytes[0]) & 0x80: + e_bytes = b'\x00' + e_bytes + if bord(n_bytes[0]) & 0x80: + n_bytes = b'\x00' + n_bytes + keyparts = [b'ssh-rsa', e_bytes, n_bytes] + keystring = b''.join([struct.pack(">I", len(kp)) + kp for kp in keyparts]) + return b'ssh-rsa ' + binascii.b2a_base64(keystring)[:-1] + + # DER format is always used, even in case of PEM, which simply + # encodes it into BASE64. + if self.has_private(): + binary_key = DerSequence([0, + self.n, + self.e, + self.d, + self.p, + self.q, + self.d % (self.p-1), + self.d % (self.q-1), + Integer(self.q).inverse(self.p) + ]).encode() + if pkcs == 1: + key_type = 'RSA PRIVATE KEY' + if format == 'DER' and passphrase: + raise ValueError("PKCS#1 private key cannot be encrypted") + else: # PKCS#8 + from Cryptodome.IO import PKCS8 + + if format == 'PEM' and protection is None: + key_type = 'PRIVATE KEY' + binary_key = PKCS8.wrap(binary_key, oid, None) + else: + key_type = 'ENCRYPTED PRIVATE KEY' + if not protection: + protection = 'PBKDF2WithHMAC-SHA1AndDES-EDE3-CBC' + binary_key = PKCS8.wrap(binary_key, oid, + passphrase, protection) + passphrase = None + else: + key_type = "PUBLIC KEY" + binary_key = _create_subject_public_key_info(oid, + DerSequence([self.n, + self.e]) + ) + + if format == 'DER': + return binary_key + if format == 'PEM': + from Cryptodome.IO import PEM + + pem_str = PEM.encode(binary_key, key_type, passphrase, randfunc) + return tobytes(pem_str) + + raise ValueError("Unknown key format '%s'. Cannot export the RSA key." % format) + + # Backward compatibility + exportKey = export_key + + # Methods defined in PyCryptodome that we don't support anymore + def sign(self, M, K): + raise NotImplementedError("Use module Cryptodome.Signature.pkcs1_15 instead") + + def verify(self, M, signature): + raise NotImplementedError("Use module Cryptodome.Signature.pkcs1_15 instead") + + def encrypt(self, plaintext, K): + raise NotImplementedError("Use module Cryptodome.Cipher.PKCS1_OAEP instead") + + def decrypt(self, ciphertext): + raise NotImplementedError("Use module Cryptodome.Cipher.PKCS1_OAEP instead") + + def blind(self, M, B): + raise NotImplementedError + + def unblind(self, M, B): + raise NotImplementedError + + def size(self): + raise NotImplementedError + + +def generate(bits, randfunc=None, e=65537): + """Create a new RSA key pair. + + The algorithm closely follows NIST `FIPS 186-4`_ in its + sections B.3.1 and B.3.3. The modulus is the product of + two non-strong probable primes. + Each prime passes a suitable number of Miller-Rabin tests + with random bases and a single Lucas test. + + Args: + bits (integer): + Key length, or size (in bits) of the RSA modulus. + It must be at least 1024, but **2048 is recommended.** + The FIPS standard only defines 1024, 2048 and 3072. + randfunc (callable): + Function that returns random bytes. + The default is :func:`Cryptodome.Random.get_random_bytes`. + e (integer): + 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 FIPS standard requires the public exponent to be + at least 65537 (the default). + + Returns: an RSA key object (:class:`RsaKey`, with private key). + + .. _FIPS 186-4: http://nvlpubs.nist.gov/nistpubs/FIPS/NIST.FIPS.186-4.pdf + """ + + if bits < 1024: + raise ValueError("RSA modulus length must be >= 1024") + if e % 2 == 0 or e < 3: + raise ValueError("RSA public exponent must be a positive, odd integer larger than 2.") + + if randfunc is None: + randfunc = Random.get_random_bytes + + d = n = Integer(1) + e = Integer(e) + + while n.size_in_bits() != bits and d < (1 << (bits // 2)): + # Generate the prime factors of n: p and q. + # By construciton, their product is always + # 2^{bits-1} < p*q < 2^bits. + size_q = bits // 2 + size_p = bits - size_q + + min_p = min_q = (Integer(1) << (2 * size_q - 1)).sqrt() + if size_q != size_p: + min_p = (Integer(1) << (2 * size_p - 1)).sqrt() + + def filter_p(candidate): + return candidate > min_p and (candidate - 1).gcd(e) == 1 + + p = generate_probable_prime(exact_bits=size_p, + randfunc=randfunc, + prime_filter=filter_p) + + min_distance = Integer(1) << (bits // 2 - 100) + + def filter_q(candidate): + return (candidate > min_q and + (candidate - 1).gcd(e) == 1 and + abs(candidate - p) > min_distance) + + q = generate_probable_prime(exact_bits=size_q, + randfunc=randfunc, + prime_filter=filter_q) + + n = p * q + lcm = (p - 1).lcm(q - 1) + d = e.inverse(lcm) + + if p > q: + p, q = q, p + + u = p.inverse(q) + + return RsaKey(n=n, e=e, d=d, p=p, q=q, u=u) + + +def construct(rsa_components, consistency_check=True): + r"""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: + + .. math:: + + \begin{align} + p*q &= n \\ + e*d &\equiv 1 ( \text{mod lcm} [(p-1)(q-1)]) \\ + p*u &\equiv 1 ( \text{mod } q) + \end{align} + + Args: + rsa_components (tuple): + A tuple of 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, but the other factor *q* must also be present. + 5. Second factor of *n* (*q*). Optional. + 6. CRT coefficient *q*, that is :math:`p^{-1} \text{mod }q`. Optional. + + consistency_check (boolean): + If ``True``, the library will verify that the provided components + fulfil the main RSA properties. + + Raises: + ValueError: when the key being imported fails the most basic RSA validity checks. + + Returns: An RSA key object (:class:`RsaKey`). + """ + + class InputComps(object): + pass + + input_comps = InputComps() + for (comp, value) in zip(('n', 'e', 'd', 'p', 'q', 'u'), rsa_components): + setattr(input_comps, comp, Integer(value)) + + n = input_comps.n + e = input_comps.e + if not hasattr(input_comps, 'd'): + key = RsaKey(n=n, e=e) + else: + d = input_comps.d + if hasattr(input_comps, 'q'): + p = input_comps.p + q = input_comps.q + else: + # Compute factors p and q from the private exponent d. + # We assume that n has no more than two factors. + # See 8.2.2(i) in Handbook of Applied Cryptography. + ktot = d * e - 1 + # The quantity d*e-1 is a multiple of phi(n), even, + # and can be represented as t*2^s. + t = ktot + while t % 2 == 0: + t //= 2 + # Cycle through all multiplicative inverses in Zn. + # The algorithm is non-deterministic, but there is a 50% chance + # any candidate a leads to successful factoring. + # See "Digitalized Signatures and Public Key Functions as Intractable + # as Factorization", M. Rabin, 1979 + spotted = False + a = Integer(2) + while not spotted and a < 100: + k = Integer(t) + # Cycle through all values a^{t*2^i}=a^k + while k < ktot: + cand = pow(a, k, n) + # Check if a^k is a non-trivial root of unity (mod n) + if cand != 1 and cand != (n - 1) and pow(cand, 2, n) == 1: + # We have found a number such that (cand-1)(cand+1)=0 (mod n). + # Either of the terms divides n. + p = Integer(n).gcd(cand + 1) + spotted = True + break + k *= 2 + # This value was not any good... let's try another! + a += 2 + if not spotted: + raise ValueError("Unable to compute factors p and q from exponent d.") + # Found ! + assert ((n % p) == 0) + q = n // p + + if hasattr(input_comps, 'u'): + u = input_comps.u + else: + u = p.inverse(q) + + # Build key object + key = RsaKey(n=n, e=e, d=d, p=p, q=q, u=u) + + # Verify consistency of the key + if consistency_check: + + # Modulus and public exponent must be coprime + if e <= 1 or e >= n: + raise ValueError("Invalid RSA public exponent") + if Integer(n).gcd(e) != 1: + raise ValueError("RSA public exponent is not coprime to modulus") + + # For RSA, modulus must be odd + if not n & 1: + raise ValueError("RSA modulus is not odd") + + if key.has_private(): + # Modulus and private exponent must be coprime + if d <= 1 or d >= n: + raise ValueError("Invalid RSA private exponent") + if Integer(n).gcd(d) != 1: + raise ValueError("RSA private exponent is not coprime to modulus") + # Modulus must be product of 2 primes + if p * q != n: + raise ValueError("RSA factors do not match modulus") + if test_probable_prime(p) == COMPOSITE: + raise ValueError("RSA factor p is composite") + if test_probable_prime(q) == COMPOSITE: + raise ValueError("RSA factor q is composite") + # See Carmichael theorem + phi = (p - 1) * (q - 1) + lcm = phi // (p - 1).gcd(q - 1) + if (e * d % int(lcm)) != 1: + raise ValueError("Invalid RSA condition") + if hasattr(key, 'u'): + # CRT coefficient + if u <= 1 or u >= q: + raise ValueError("Invalid RSA component u") + if (p * u % q) != 1: + raise ValueError("Invalid RSA component u with p") + + return key + + +def _import_pkcs1_private(encoded, *kwargs): + # RSAPrivateKey ::= SEQUENCE { + # version Version, + # modulus INTEGER, -- n + # publicExponent INTEGER, -- e + # privateExponent INTEGER, -- d + # prime1 INTEGER, -- p + # prime2 INTEGER, -- q + # exponent1 INTEGER, -- d mod (p-1) + # exponent2 INTEGER, -- d mod (q-1) + # coefficient INTEGER -- (inverse of q) mod p + # } + # + # Version ::= INTEGER + der = DerSequence().decode(encoded, nr_elements=9, only_ints_expected=True) + if der[0] != 0: + raise ValueError("No PKCS#1 encoding of an RSA private key") + return construct(der[1:6] + [Integer(der[4]).inverse(der[5])]) + + +def _import_pkcs1_public(encoded, *kwargs): + # RSAPublicKey ::= SEQUENCE { + # modulus INTEGER, -- n + # publicExponent INTEGER -- e + # } + der = DerSequence().decode(encoded, nr_elements=2, only_ints_expected=True) + return construct(der) + + +def _import_subjectPublicKeyInfo(encoded, *kwargs): + + algoid, encoded_key, params = _expand_subject_public_key_info(encoded) + if algoid != oid or params is not None: + raise ValueError("No RSA subjectPublicKeyInfo") + return _import_pkcs1_public(encoded_key) + + +def _import_x509_cert(encoded, *kwargs): + + sp_info = _extract_subject_public_key_info(encoded) + return _import_subjectPublicKeyInfo(sp_info) + + +def _import_pkcs8(encoded, passphrase): + from Cryptodome.IO import PKCS8 + + k = PKCS8.unwrap(encoded, passphrase) + if k[0] != oid: + raise ValueError("No PKCS#8 encoded RSA key") + return _import_keyDER(k[1], passphrase) + + +def _import_keyDER(extern_key, passphrase): + """Import an RSA key (public or private half), encoded in DER form.""" + + decodings = (_import_pkcs1_private, + _import_pkcs1_public, + _import_subjectPublicKeyInfo, + _import_x509_cert, + _import_pkcs8) + + for decoding in decodings: + try: + return decoding(extern_key, passphrase) + except ValueError: + pass + + raise ValueError("RSA key format is not supported") + + +def _import_openssh_private_rsa(data, password): + + from ._openssh import (import_openssh_private_generic, + read_bytes, read_string, check_padding) + + ssh_name, decrypted = import_openssh_private_generic(data, password) + + if ssh_name != "ssh-rsa": + raise ValueError("This SSH key is not RSA") + + n, decrypted = read_bytes(decrypted) + e, decrypted = read_bytes(decrypted) + d, decrypted = read_bytes(decrypted) + iqmp, decrypted = read_bytes(decrypted) + p, decrypted = read_bytes(decrypted) + q, decrypted = read_bytes(decrypted) + + _, padded = read_string(decrypted) # Comment + check_padding(padded) + + build = [Integer.from_bytes(x) for x in (n, e, d, q, p, iqmp)] + return construct(build) + + +def import_key(extern_key, passphrase=None): + """Import an RSA key (public or private). + + Args: + extern_key (string or byte string): + The RSA key to import. + + The following formats are supported for an RSA **public key**: + + - X.509 certificate (binary or PEM format) + - X.509 ``subjectPublicKeyInfo`` DER SEQUENCE (binary or PEM + encoding) + - `PKCS#1`_ ``RSAPublicKey`` DER SEQUENCE (binary or PEM encoding) + - An OpenSSH line (e.g. the content of ``~/.ssh/id_ecdsa``, ASCII) + + The following formats are supported for an RSA **private key**: + + - PKCS#1 ``RSAPrivateKey`` DER SEQUENCE (binary or PEM encoding) + - `PKCS#8`_ ``PrivateKeyInfo`` or ``EncryptedPrivateKeyInfo`` + DER SEQUENCE (binary or PEM encoding) + - OpenSSH (text format, introduced in `OpenSSH 6.5`_) + + For details about the PEM encoding, see `RFC1421`_/`RFC1423`_. + + passphrase (string or byte string): + For private keys only, the pass phrase that encrypts the key. + + Returns: An RSA key object (:class:`RsaKey`). + + Raises: + 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 + .. _`OpenSSH 6.5`: https://flak.tedunangst.com/post/new-openssh-key-format-and-bcrypt-pbkdf + """ + + from Cryptodome.IO import PEM + + extern_key = tobytes(extern_key) + if passphrase is not None: + passphrase = tobytes(passphrase) + + if extern_key.startswith(b'-----BEGIN OPENSSH PRIVATE KEY'): + text_encoded = tostr(extern_key) + openssh_encoded, marker, enc_flag = PEM.decode(text_encoded, passphrase) + result = _import_openssh_private_rsa(openssh_encoded, passphrase) + return result + + if extern_key.startswith(b'-----'): + # This is probably a PEM encoded key. + (der, marker, enc_flag) = PEM.decode(tostr(extern_key), passphrase) + if enc_flag: + passphrase = None + return _import_keyDER(der, passphrase) + + if extern_key.startswith(b'ssh-rsa '): + # This is probably an OpenSSH key + keystring = binascii.a2b_base64(extern_key.split(b' ')[1]) + keyparts = [] + while len(keystring) > 4: + length = struct.unpack(">I", keystring[:4])[0] + keyparts.append(keystring[4:4 + length]) + keystring = keystring[4 + length:] + e = Integer.from_bytes(keyparts[1]) + n = Integer.from_bytes(keyparts[2]) + return construct([n, e]) + + if len(extern_key) > 0 and bord(extern_key[0]) == 0x30: + # This is probably a DER encoded key + return _import_keyDER(extern_key, passphrase) + + raise ValueError("RSA key format is not supported") + + +# Backward compatibility +importKey = import_key + +#: `Object ID`_ for the RSA encryption algorithm. This OID often indicates +#: a generic RSA key, even when such key will be actually used for digital +#: signatures. +#: +#: .. _`Object ID`: http://www.alvestrand.no/objectid/1.2.840.113549.1.1.1.html +oid = "1.2.840.113549.1.1.1" -- cgit v1.2.3