def test_rsa_pkcs1v15_encrypt(self): original_data = b'This is data to encrypt' private = asymmetric.load_private_key(os.path.join(fixtures_dir, 'keys/test.key')) public = asymmetric.load_public_key(os.path.join(fixtures_dir, 'keys/test.crt')) ciphertext = asymmetric.rsa_pkcs1v15_encrypt(public, original_data) self.assertIsInstance(ciphertext, byte_cls) plaintext = asymmetric.rsa_pkcs1v15_decrypt(private, ciphertext) self.assertEqual(original_data, plaintext)
def test_terrible_hybrid_file_encryption_app(self): # Proof of concept code only! import io from oscrypto.asymmetric import load_public_key, rsa_pkcs1v15_encrypt from oscrypto.symmetric import ( aes_cbc_pkcs7_encrypt, aes_cbc_pkcs7_decrypt, ) # A key we generated earlier self.session.generate_keypair(KeyType.RSA, 1024) pub = self.session.get_key(key_type=KeyType.RSA, object_class=ObjectClass.PUBLIC_KEY) pub = load_public_key(encode_rsa_public_key(pub)) key = self.session.generate_random(256) iv = self.session.generate_random(128) source = b'This is my amazing file' with io.BytesIO() as dest: # Write a 128-byte header containing our key and our IV # strictly speaking we don't need to keep the IV secure but # we may as well. # # FIXME: Because this is RSA 1.5, we should fill the rest of the # frame with nonsense self.assertEqual(dest.write(rsa_pkcs1v15_encrypt(pub, key + iv)), 128) _, ciphertext = aes_cbc_pkcs7_encrypt(key, source, iv) dest.write(ciphertext) # Time passes dest.seek(0) # Look up our private key priv = self.session.get_key(key_type=KeyType.RSA, object_class=ObjectClass.PRIVATE_KEY) # Read the header header = dest.read(priv.key_length // 8) header = priv.decrypt(header, mechanism=Mechanism.RSA_PKCS) # The first 32 bytes is our key key, header = header[:32], header[32:] # The next 16 bytes is the IV iv = header[:16] # We can ignore the rest plaintext = aes_cbc_pkcs7_decrypt(key, dest.read(), iv) self.assertEqual(source, plaintext)
def public_encrypt(key, data, oaep): """ public key encryption using rsa with pkcs1-oaep padding. returns the base64-encoded encrypted data data: the data to be encrypted, bytes key: pem-formatted key string or bytes oaep: whether to use oaep padding or not """ if isinstance(key, str): key = key.encode("ascii") pubkey = load_public_key(key) if oaep: encrypted = rsa_oaep_encrypt(pubkey, data) else: encrypted = rsa_pkcs1v15_encrypt(pubkey, data) return b64encode(encrypted).decode("ascii")
def test_rsa(self): # A key we generated earlier self.session.generate_keypair(KeyType.RSA, 1024) pub = self.session.get_key(key_type=KeyType.RSA, object_class=ObjectClass.PUBLIC_KEY) pub = encode_rsa_public_key(pub) from oscrypto.asymmetric import load_public_key, rsa_pkcs1v15_encrypt pub = load_public_key(pub) crypttext = rsa_pkcs1v15_encrypt(pub, b'Data to encrypt') priv = self.session.get_key(key_type=KeyType.RSA, object_class=ObjectClass.PRIVATE_KEY) plaintext = priv.decrypt(crypttext, mechanism=Mechanism.RSA_PKCS) self.assertEqual(plaintext, b'Data to encrypt')
def on_get(self, req, resp): operation = req.get_param("operation", required=True) if operation.lower() == "getcacert": resp.body = keys.parse_certificate( self.authority.certificate_buf).dump() resp.append_header("Content-Type", "application/x-x509-ca-cert") return # If we bump into exceptions later encrypted_container = b"" attr_list = [ cms.CMSAttribute({ 'type': "message_type", 'values': ["3"] }), cms.CMSAttribute({ 'type': "pki_status", 'values': ["2"] # rejected }) ] try: info = cms.ContentInfo.load( b64decode(req.get_param("message", required=True))) ############################################### ### Verify signature of the outer container ### ############################################### signed_envelope = info['content'] encap_content_info = signed_envelope['encap_content_info'] encap_content = encap_content_info['content'] # TODO: try except current_certificate, = signed_envelope["certificates"] signer, = signed_envelope["signer_infos"] # TODO: compare cert to current one if we are renewing assert signer["digest_algorithm"]["algorithm"].native == "md5" assert signer["signature_algorithm"][ "algorithm"].native == "rsassa_pkcs1v15" message_digest = None transaction_id = None sender_nonce = None for attr in signer["signed_attrs"]: if attr["type"].native == "sender_nonce": sender_nonce, = attr["values"] elif attr["type"].native == "trans_id": transaction_id, = attr["values"] elif attr["type"].native == "message_digest": message_digest, = attr["values"] if hashlib.md5(encap_content.native).digest( ) != message_digest.native: raise SCEPBadMessageCheck() assert message_digest msg = signer["signed_attrs"].dump(force=True) assert msg[0] == 160 # Verify signature try: asymmetric.rsa_pkcs1v15_verify( asymmetric.load_certificate(current_certificate.dump()), signer["signature"].native, b"\x31" + msg[1:], # wtf?! "md5") except SignatureError: raise SCEPBadMessageCheck() ############################### ### Decrypt inner container ### ############################### info = cms.ContentInfo.load(encap_content.native) encrypted_envelope = info['content'] encrypted_content_info = encrypted_envelope[ 'encrypted_content_info'] iv = encrypted_content_info['content_encryption_algorithm'][ 'parameters'].native if encrypted_content_info['content_encryption_algorithm'][ "algorithm"].native != "des": raise SCEPBadAlgo() encrypted_content = encrypted_content_info[ 'encrypted_content'].native recipient, = encrypted_envelope['recipient_infos'] if recipient.native["rid"][ "serial_number"] != self.authority.certificate.serial_number: raise SCEPBadCertId() # Since CA private key is not directly readable here, we'll redirect it to signer socket key = asymmetric.rsa_pkcs1v15_decrypt( self.authority.private_key, recipient.native["encrypted_key"]) if len(key) == 8: key = key * 3 # Convert DES to 3DES buf = symmetric.tripledes_cbc_pkcs5_decrypt( key, encrypted_content, iv) _, _, common_name = self.authority.store_request(buf, overwrite=True) cert, buf = self.authority.sign(common_name, overwrite=True) signed_certificate = asymmetric.load_certificate(buf) content = signed_certificate.asn1.dump() except SCEPError as e: attr_list.append( cms.CMSAttribute({ 'type': "fail_info", 'values': ["%d" % e.code] })) else: ################################## ### Degenerate inner container ### ################################## degenerate = cms.ContentInfo({ 'content_type': "signed_data", 'content': cms.SignedData({ 'version': "v1", 'certificates': [signed_certificate.asn1], 'digest_algorithms': [cms.DigestAlgorithm({'algorithm': "md5"})], 'encap_content_info': { 'content_type': "data", 'content': cms.ContentInfo({ 'content_type': "signed_data", 'content': None }).dump() }, 'signer_infos': [] }) }) ################################ ### Encrypt middle container ### ################################ key = os.urandom(8) iv, encrypted_content = symmetric.des_cbc_pkcs5_encrypt( key, degenerate.dump(), os.urandom(8)) assert degenerate.dump() == symmetric.tripledes_cbc_pkcs5_decrypt( key * 3, encrypted_content, iv) ri = cms.RecipientInfo({ 'ktri': cms.KeyTransRecipientInfo({ 'version': "v0", 'rid': cms.RecipientIdentifier({ 'issuer_and_serial_number': cms.IssuerAndSerialNumber({ 'issuer': current_certificate.chosen["tbs_certificate"] ["issuer"], 'serial_number': current_certificate.chosen["tbs_certificate"] ["serial_number"], }), }), 'key_encryption_algorithm': { 'algorithm': "rsa" }, 'encrypted_key': asymmetric.rsa_pkcs1v15_encrypt( asymmetric.load_certificate( current_certificate.chosen.dump()), key) }) }) encrypted_container = cms.ContentInfo({ 'content_type': "enveloped_data", 'content': cms.EnvelopedData({ 'version': "v1", 'recipient_infos': [ri], 'encrypted_content_info': { 'content_type': "data", 'content_encryption_algorithm': { 'algorithm': "des", 'parameters': iv }, 'encrypted_content': encrypted_content } }) }).dump() attr_list = [ cms.CMSAttribute({ 'type': "message_digest", 'values': [hashlib.sha1(encrypted_container).digest()] }), cms.CMSAttribute({ 'type': "message_type", 'values': ["3"] }), cms.CMSAttribute({ 'type': "pki_status", 'values': ["0"] # ok }) ] finally: ############################## ### Signed outer container ### ############################## attrs = cms.CMSAttributes(attr_list + [ cms.CMSAttribute({ 'type': "recipient_nonce", 'values': [sender_nonce] }), cms.CMSAttribute({ 'type': "trans_id", 'values': [transaction_id] }) ]) signer = cms.SignerInfo({ "signed_attrs": attrs, 'version': "v1", 'sid': cms.SignerIdentifier({ 'issuer_and_serial_number': cms.IssuerAndSerialNumber({ 'issuer': self.authority.certificate.issuer, 'serial_number': self.authority.certificate.serial_number, }), }), 'digest_algorithm': algos.DigestAlgorithm({'algorithm': "sha1"}), 'signature_algorithm': algos.SignedDigestAlgorithm({'algorithm': "rsassa_pkcs1v15"}), 'signature': asymmetric.rsa_pkcs1v15_sign(self.authority.private_key, b"\x31" + attrs.dump()[1:], "sha1") }) resp.append_header("Content-Type", "application/x-pki-message") resp.body = cms.ContentInfo({ 'content_type': "signed_data", 'content': cms.SignedData({ 'version': "v1", 'certificates': [self.authority.certificate], 'digest_algorithms': [cms.DigestAlgorithm({'algorithm': "sha1"})], 'encap_content_info': { 'content_type': "data", 'content': encrypted_container }, 'signer_infos': [signer] }) }).dump()
def encrypt_message(data_to_encrypt, enc_alg, encryption_cert): """Function encrypts data and returns the generated ASN.1 :param data_to_encrypt: A byte string of the data to be encrypted :param enc_alg: The algorithm to be used for encrypting the data :param encryption_cert: The certificate to be used for encrypting the data :return: A CMS ASN.1 byte string of the encrypted data. """ enc_alg_list = enc_alg.split('_') cipher, key_length, mode = enc_alg_list[0], enc_alg_list[1], enc_alg_list[ 2] enc_alg_asn1, encrypted_content = None, None # Generate the symmetric encryption key and encrypt the message key = util.rand_bytes(int(key_length) // 8) if cipher == 'tripledes': algorithm_id = '1.2.840.113549.3.7' iv, encrypted_content = symmetric.tripledes_cbc_pkcs5_encrypt( key, data_to_encrypt, None) enc_alg_asn1 = algos.EncryptionAlgorithm({ 'algorithm': algorithm_id, 'parameters': cms.OctetString(iv) }) elif cipher == 'rc2': algorithm_id = '1.2.840.113549.3.2' iv, encrypted_content = symmetric.rc2_cbc_pkcs5_encrypt( key, data_to_encrypt, None) enc_alg_asn1 = algos.EncryptionAlgorithm({ 'algorithm': algorithm_id, 'parameters': algos.Rc2Params({'iv': cms.OctetString(iv)}) }) elif cipher == 'rc4': algorithm_id = '1.2.840.113549.3.4' encrypted_content = symmetric.rc4_encrypt(key, data_to_encrypt) enc_alg_asn1 = algos.EncryptionAlgorithm({ 'algorithm': algorithm_id, }) elif cipher == 'aes': if key_length == '128': algorithm_id = '2.16.840.1.101.3.4.1.2' elif key_length == '192': algorithm_id = '2.16.840.1.101.3.4.1.22' else: algorithm_id = '2.16.840.1.101.3.4.1.42' iv, encrypted_content = symmetric.aes_cbc_pkcs7_encrypt( key, data_to_encrypt, None) enc_alg_asn1 = algos.EncryptionAlgorithm({ 'algorithm': algorithm_id, 'parameters': cms.OctetString(iv) }) # Encrypt the key and build the ASN.1 message encrypted_key = asymmetric.rsa_pkcs1v15_encrypt(encryption_cert, key) return cms.ContentInfo({ 'content_type': cms.ContentType('enveloped_data'), 'content': cms.EnvelopedData({ 'version': cms.CMSVersion('v0'), 'recipient_infos': [ cms.KeyTransRecipientInfo({ 'version': cms.CMSVersion('v0'), 'rid': cms.RecipientIdentifier({ 'issuer_and_serial_number': cms.IssuerAndSerialNumber({ 'issuer': encryption_cert.asn1['tbs_certificate']['issuer'], 'serial_number': encryption_cert.asn1['tbs_certificate'] ['serial_number'] }) }), 'key_encryption_algorithm': cms.KeyEncryptionAlgorithm( {'algorithm': cms.KeyEncryptionAlgorithmId('rsa')}), 'encrypted_key': cms.OctetString(encrypted_key) }) ], 'encrypted_content_info': cms.EncryptedContentInfo({ 'content_type': cms.ContentType('data'), 'content_encryption_algorithm': enc_alg_asn1, 'encrypted_content': encrypted_content }) }) }).dump()
def encrypt_message(data_to_encrypt, enc_alg, encryption_cert): """Function encrypts data and returns the generated ASN.1 :param data_to_encrypt: A byte string of the data to be encrypted :param enc_alg: The algorithm to be used for encrypting the data :param encryption_cert: The certificate to be used for encrypting the data :return: A CMS ASN.1 byte string of the encrypted data. """ enc_alg_list = enc_alg.split("_") cipher, key_length, _ = enc_alg_list[0], enc_alg_list[1], enc_alg_list[2] # Generate the symmetric encryption key and encrypt the message key = util.rand_bytes(int(key_length) // 8) if cipher == "tripledes": algorithm_id = "1.2.840.113549.3.7" iv, encrypted_content = symmetric.tripledes_cbc_pkcs5_encrypt( key, data_to_encrypt, None) enc_alg_asn1 = algos.EncryptionAlgorithm({ "algorithm": algorithm_id, "parameters": cms.OctetString(iv) }) elif cipher == "rc2": algorithm_id = "1.2.840.113549.3.2" iv, encrypted_content = symmetric.rc2_cbc_pkcs5_encrypt( key, data_to_encrypt, None) enc_alg_asn1 = algos.EncryptionAlgorithm({ "algorithm": algorithm_id, "parameters": algos.Rc2Params({"iv": cms.OctetString(iv)}), }) elif cipher == "rc4": algorithm_id = "1.2.840.113549.3.4" encrypted_content = symmetric.rc4_encrypt(key, data_to_encrypt) enc_alg_asn1 = algos.EncryptionAlgorithm({ "algorithm": algorithm_id, }) elif cipher == "aes": if key_length == "128": algorithm_id = "2.16.840.1.101.3.4.1.2" elif key_length == "192": algorithm_id = "2.16.840.1.101.3.4.1.22" else: algorithm_id = "2.16.840.1.101.3.4.1.42" iv, encrypted_content = symmetric.aes_cbc_pkcs7_encrypt( key, data_to_encrypt, None) enc_alg_asn1 = algos.EncryptionAlgorithm({ "algorithm": algorithm_id, "parameters": cms.OctetString(iv) }) elif cipher == "des": algorithm_id = "1.3.14.3.2.7" iv, encrypted_content = symmetric.des_cbc_pkcs5_encrypt( key, data_to_encrypt, None) enc_alg_asn1 = algos.EncryptionAlgorithm({ "algorithm": algorithm_id, "parameters": cms.OctetString(iv) }) else: raise AS2Exception("Unsupported Encryption Algorithm") # Encrypt the key and build the ASN.1 message encrypted_key = asymmetric.rsa_pkcs1v15_encrypt(encryption_cert, key) return cms.ContentInfo({ "content_type": cms.ContentType("enveloped_data"), "content": cms.EnvelopedData({ "version": cms.CMSVersion("v0"), "recipient_infos": [ cms.KeyTransRecipientInfo({ "version": cms.CMSVersion("v0"), "rid": cms.RecipientIdentifier({ "issuer_and_serial_number": cms.IssuerAndSerialNumber({ "issuer": encryption_cert.asn1["tbs_certificate"]["issuer"], "serial_number": encryption_cert.asn1["tbs_certificate"] ["serial_number"], }) }), "key_encryption_algorithm": cms.KeyEncryptionAlgorithm( {"algorithm": cms.KeyEncryptionAlgorithmId("rsa")}), "encrypted_key": cms.OctetString(encrypted_key), }) ], "encrypted_content_info": cms.EncryptedContentInfo({ "content_type": cms.ContentType("data"), "content_encryption_algorithm": enc_alg_asn1, "encrypted_content": encrypted_content, }), }), }).dump()
def encrypt(self, user, message): return asymmetric.rsa_pkcs1v15_encrypt(user.public_key, message)
def on_get(self, req, resp): operation = req.get_param("operation", required=True) if operation == "GetCACert": resp.body = keys.parse_certificate( self.authority.certificate_buf).dump() resp.append_header("Content-Type", "application/x-x509-ca-cert") return elif operation == "GetCACaps": # TODO: return renewal flag based on renewal subnets config option resp.body = "Renewal\nMD5\nSHA-1\nSHA-256\nSHA-512\nDES3\n" return elif operation == "PKIOperation": pass else: raise falcon.HTTPBadRequest("Bad request", "Unknown operation %s" % operation) # If we bump into exceptions later encrypted_container = b"" attr_list = [ cms.CMSAttribute({ 'type': "message_type", 'values': ["3"] }), cms.CMSAttribute({ 'type': "pki_status", 'values': ["2"] # rejected }) ] try: info = cms.ContentInfo.load( b64decode(req.get_param("message", required=True))) ############################################### ### Verify signature of the outer container ### ############################################### signed_envelope = info['content'] encap_content_info = signed_envelope['encap_content_info'] encap_content = encap_content_info['content'] # TODO: try except current_certificate, = signed_envelope["certificates"] signer, = signed_envelope["signer_infos"] # TODO: compare cert to current one if we are renewing digest_algorithm = signer["digest_algorithm"]["algorithm"].native signature_algorithm = signer["signature_algorithm"][ "algorithm"].native if digest_algorithm not in ("md5", "sha1", "sha256", "sha512"): raise SCEPBadAlgo() if signature_algorithm != "rsassa_pkcs1v15": raise SCEPBadAlgo() message_digest = None transaction_id = None sender_nonce = None for attr in signer["signed_attrs"]: if attr["type"].native == "sender_nonce": sender_nonce, = attr["values"] elif attr["type"].native == "trans_id": transaction_id, = attr["values"] elif attr["type"].native == "message_digest": message_digest, = attr["values"] if getattr(hashlib, digest_algorithm)(encap_content.native).digest( ) != message_digest.native: raise SCEPDigestMismatch() if not sender_nonce: raise SCEPBadRequest() if not transaction_id: raise SCEPBadRequest() assert message_digest msg = signer["signed_attrs"].dump(force=True) assert msg[0] == 160 # Verify signature try: asymmetric.rsa_pkcs1v15_verify( asymmetric.load_certificate(current_certificate.dump()), signer["signature"].native, b"\x31" + msg[1:], # wtf?! "md5") except SignatureError: raise SCEPSignatureMismatch() ############################### ### Decrypt inner container ### ############################### info = cms.ContentInfo.load(encap_content.native) encrypted_envelope = info['content'] encrypted_content_info = encrypted_envelope[ 'encrypted_content_info'] iv = encrypted_content_info['content_encryption_algorithm'][ 'parameters'].native if encrypted_content_info['content_encryption_algorithm'][ "algorithm"].native != "des": raise SCEPBadAlgo() encrypted_content = encrypted_content_info[ 'encrypted_content'].native recipient, = encrypted_envelope['recipient_infos'] if recipient.native["rid"][ "serial_number"] != self.authority.certificate.serial_number: raise SCEPBadCertId() key = asymmetric.rsa_pkcs1v15_decrypt( self.authority.private_key, recipient.native["encrypted_key"]) if len(key) == 8: key = key * 3 # Convert DES to 3DES buf = symmetric.tripledes_cbc_pkcs5_decrypt( key, encrypted_content, iv) _, _, common_name = self.authority.store_request(buf, overwrite=True) logger.info( "SCEP client from %s requested with %s digest algorithm, %s signature", req.context["remote_addr"], digest_algorithm, signature_algorithm) cert, buf = self.authority.sign(common_name, profile=config.PROFILES["gw"], overwrite=True) signed_certificate = asymmetric.load_certificate(buf) content = signed_certificate.asn1.dump() except SCEPError as e: attr_list.append( cms.CMSAttribute({ 'type': "fail_info", 'values': ["%d" % e.code] })) logger.info("Failed to sign SCEP request due to: %s" % e.explaination) else: ################################## ### Degenerate inner container ### ################################## degenerate = cms.ContentInfo({ 'content_type': "signed_data", 'content': cms.SignedData({ 'version': "v1", 'certificates': [signed_certificate.asn1], 'digest_algorithms': [cms.DigestAlgorithm({'algorithm': digest_algorithm})], 'encap_content_info': { 'content_type': "data", 'content': cms.ContentInfo({ 'content_type': "signed_data", 'content': None }).dump() }, 'signer_infos': [] }) }) ################################ ### Encrypt middle container ### ################################ key = os.urandom(8) iv, encrypted_content = symmetric.des_cbc_pkcs5_encrypt( key, degenerate.dump(), os.urandom(8)) assert degenerate.dump() == symmetric.tripledes_cbc_pkcs5_decrypt( key * 3, encrypted_content, iv) ri = cms.RecipientInfo({ 'ktri': cms.KeyTransRecipientInfo({ 'version': "v0", 'rid': cms.RecipientIdentifier({ 'issuer_and_serial_number': cms.IssuerAndSerialNumber({ 'issuer': current_certificate.chosen["tbs_certificate"] ["issuer"], 'serial_number': current_certificate.chosen["tbs_certificate"] ["serial_number"], }), }), 'key_encryption_algorithm': { 'algorithm': "rsa" }, 'encrypted_key': asymmetric.rsa_pkcs1v15_encrypt( asymmetric.load_certificate( current_certificate.chosen.dump()), key) }) }) encrypted_container = cms.ContentInfo({ 'content_type': "enveloped_data", 'content': cms.EnvelopedData({ 'version': "v1", 'recipient_infos': [ri], 'encrypted_content_info': { 'content_type': "data", 'content_encryption_algorithm': { 'algorithm': "des", 'parameters': iv }, 'encrypted_content': encrypted_content } }) }).dump() attr_list = [ cms.CMSAttribute({ 'type': "message_digest", 'values': [ getattr( hashlib, digest_algorithm)(encrypted_container).digest() ] }), cms.CMSAttribute({ 'type': "message_type", 'values': ["3"] }), cms.CMSAttribute({ 'type': "pki_status", 'values': ["0"] # ok }) ] finally: ############################## ### Signed outer container ### ############################## attrs = cms.CMSAttributes(attr_list + [ cms.CMSAttribute({ 'type': "recipient_nonce", 'values': [sender_nonce] }), cms.CMSAttribute({ 'type': "trans_id", 'values': [transaction_id] }) ]) signer = cms.SignerInfo({ "signed_attrs": attrs, 'version': "v1", 'sid': cms.SignerIdentifier({ 'issuer_and_serial_number': cms.IssuerAndSerialNumber({ 'issuer': self.authority.certificate.issuer, 'serial_number': self.authority.certificate.serial_number, }), }), 'digest_algorithm': algos.DigestAlgorithm({'algorithm': digest_algorithm}), 'signature_algorithm': algos.SignedDigestAlgorithm({'algorithm': "rsassa_pkcs1v15"}), 'signature': asymmetric.rsa_pkcs1v15_sign(self.authority.private_key, b"\x31" + attrs.dump()[1:], digest_algorithm) }) resp.append_header("Content-Type", "application/x-pki-message") resp.body = cms.ContentInfo({ 'content_type': "signed_data", 'content': cms.SignedData({ 'version': "v1", 'certificates': [self.authority.certificate], 'digest_algorithms': [cms.DigestAlgorithm({'algorithm': digest_algorithm})], 'encap_content_info': { 'content_type': "data", 'content': encrypted_container }, 'signer_infos': [signer] }) }).dump()
def encrypt(self, message): return asymmetric.rsa_pkcs1v15_encrypt(self.server_public_key, message)