diff options
| -rw-r--r-- | paramiko/kex_gex.py | 13 | ||||
| -rw-r--r-- | paramiko/transport.py | 27 | ||||
| -rw-r--r-- | tests/test_kex.py | 120 | ||||
| -rw-r--r-- | tests/test_transport.py | 5 |
4 files changed, 150 insertions, 15 deletions
diff --git a/paramiko/kex_gex.py b/paramiko/kex_gex.py index cb548f33..c980b690 100644 --- a/paramiko/kex_gex.py +++ b/paramiko/kex_gex.py @@ -23,7 +23,7 @@ client side, and a **lot** more on the server side. """ import os -from hashlib import sha1 +from hashlib import sha1, sha256 from paramiko import util from paramiko.common import DEBUG @@ -44,6 +44,7 @@ class KexGex (object): min_bits = 1024 max_bits = 8192 preferred_bits = 2048 + hash_algo = sha1 def __init__(self, transport): self.transport = transport @@ -87,7 +88,7 @@ class KexGex (object): return self._parse_kexdh_gex_reply(m) elif ptype == _MSG_KEXDH_GEX_REQUEST_OLD: return self._parse_kexdh_gex_request_old(m) - raise SSHException('KexGex asked to handle packet type %d' % ptype) + raise SSHException('KexGex %s asked to handle packet type %d' % self.name, ptype) ### internals... @@ -204,7 +205,7 @@ class KexGex (object): hm.add_mpint(self.e) hm.add_mpint(self.f) hm.add_mpint(K) - H = sha1(hm.asbytes()).digest() + H = self.hash_algo(hm.asbytes()).digest() self.transport._set_K_H(K, H) # sign it sig = self.transport.get_server_key().sign_ssh_data(H) @@ -239,6 +240,10 @@ class KexGex (object): hm.add_mpint(self.e) hm.add_mpint(self.f) hm.add_mpint(K) - self.transport._set_K_H(K, sha1(hm.asbytes()).digest()) + self.transport._set_K_H(K, self.hash_algo(hm.asbytes()).digest()) self.transport._verify_key(host_key, sig) self.transport._activate_outbound() + +class KexGexSHA256(KexGex): + name = 'diffie-hellman-group-exchange-sha256' + hash_algo = sha256 diff --git a/paramiko/transport.py b/paramiko/transport.py index f80aaba5..9009f9f5 100644 --- a/paramiko/transport.py +++ b/paramiko/transport.py @@ -26,7 +26,7 @@ import sys import threading import time import weakref -from hashlib import md5, sha1 +from hashlib import md5, sha1, sha256 import paramiko from paramiko import util @@ -47,7 +47,7 @@ from paramiko.common import xffffffff, cMSG_CHANNEL_OPEN, cMSG_IGNORE, \ DEFAULT_WINDOW_SIZE, DEFAULT_MAX_PACKET_SIZE from paramiko.compress import ZlibCompressor, ZlibDecompressor from paramiko.dsskey import DSSKey -from paramiko.kex_gex import KexGex +from paramiko.kex_gex import KexGex, KexGexSHA256 from paramiko.kex_group1 import KexGroup1 from paramiko.kex_group14 import KexGroup14 from paramiko.kex_gss import KexGSSGex, KexGSSGroup1, KexGSSGroup14, NullHostKey @@ -96,9 +96,13 @@ class Transport (threading.Thread, ClosingContextManager): _preferred_ciphers = ('aes128-ctr', 'aes256-ctr', 'aes128-cbc', 'blowfish-cbc', 'aes256-cbc', '3des-cbc', 'arcfour128', 'arcfour256') - _preferred_macs = ('hmac-sha1', 'hmac-md5', 'hmac-sha1-96', 'hmac-md5-96') + _preferred_macs = ('hmac-sha1', 'hmac-md5', 'hmac-sha1-96', 'hmac-md5-96', + 'hmac-sha2-256') _preferred_keys = ('ssh-rsa', 'ssh-dss', 'ecdsa-sha2-nistp256') - _preferred_kex = ( 'diffie-hellman-group14-sha1', 'diffie-hellman-group-exchange-sha1' , 'diffie-hellman-group1-sha1') + _preferred_kex = ('diffie-hellman-group-exchange-sha256', + 'diffie-hellman-group14-sha1', + 'diffie-hellman-group-exchange-sha1' , + 'diffie-hellman-group1-sha1') _preferred_compression = ('none',) _cipher_info = { @@ -115,6 +119,7 @@ class Transport (threading.Thread, ClosingContextManager): _mac_info = { 'hmac-sha1': {'class': sha1, 'size': 20}, 'hmac-sha1-96': {'class': sha1, 'size': 12}, + 'hmac-sha2-256': {'class': sha256, 'size': 32}, 'hmac-md5': {'class': md5, 'size': 16}, 'hmac-md5-96': {'class': md5, 'size': 12}, } @@ -129,6 +134,7 @@ class Transport (threading.Thread, ClosingContextManager): 'diffie-hellman-group1-sha1': KexGroup1, 'diffie-hellman-group14-sha1': KexGroup14, 'diffie-hellman-group-exchange-sha1': KexGex, + 'diffie-hellman-group-exchange-sha256': KexGexSHA256, 'gss-group1-sha1-toWM5Slw5Ew8Mqkay+al2g==': KexGSSGroup1, 'gss-group14-sha1-toWM5Slw5Ew8Mqkay+al2g==': KexGSSGroup14, 'gss-gex-sha1-toWM5Slw5Ew8Mqkay+al2g==': KexGSSGex @@ -1495,13 +1501,14 @@ class Transport (threading.Thread, ClosingContextManager): m.add_bytes(self.H) m.add_byte(b(id)) m.add_bytes(self.session_id) - out = sofar = sha1(m.asbytes()).digest() + hash_algo = self._mac_info[self.local_mac]['class'] if self.local_mac else sha1 + out = sofar = hash_algo(m.asbytes()).digest() while len(out) < nbytes: m = Message() m.add_mpint(self.K) m.add_bytes(self.H) m.add_bytes(sofar) - digest = sha1(m.asbytes()).digest() + digest = hash_algo(m.asbytes()).digest() out += digest sofar += digest return out[:nbytes] @@ -1742,10 +1749,12 @@ class Transport (threading.Thread, ClosingContextManager): self.clear_to_send_lock.release() self.in_kex = True if self.server_mode: - if (self._modulus_pack is None) and ('diffie-hellman-group-exchange-sha1' in self._preferred_kex): + mp_required_prefix = 'diffie-hellman-group-exchange-sha' + kex_mp = [k for k in self._preferred_kex if k.startswith(mp_required_prefix)] + if (self._modulus_pack is None) and (len(kex_mp) > 0): # can't do group-exchange if we don't have a pack of potential primes - pkex = list(self.get_security_options().kex) - pkex.remove('diffie-hellman-group-exchange-sha1') + pkex = [k for k in self.get_security_options().kex + if not k.startswith(mp_required_prefix)] self.get_security_options().kex = pkex available_server_keys = list(filter(list(self.server_key_dict.keys()).__contains__, self._preferred_keys)) diff --git a/tests/test_kex.py b/tests/test_kex.py index 56f1b7c7..19804fbf 100644 --- a/tests/test_kex.py +++ b/tests/test_kex.py @@ -26,7 +26,7 @@ import unittest import paramiko.util from paramiko.kex_group1 import KexGroup1 -from paramiko.kex_gex import KexGex +from paramiko.kex_gex import KexGex, KexGexSHA256 from paramiko import Message from paramiko.common import byte_chr @@ -252,3 +252,121 @@ class KexTest (unittest.TestCase): self.assertEqual(H, hexlify(transport._H).upper()) self.assertEqual(x, hexlify(transport._message.asbytes()).upper()) self.assertTrue(transport._activated) + + def test_7_gex_sha256_client(self): + transport = FakeTransport() + transport.server_mode = False + kex = KexGexSHA256(transport) + kex.start_kex() + x = b'22000004000000080000002000' + self.assertEqual(x, hexlify(transport._message.asbytes()).upper()) + self.assertEqual((paramiko.kex_gex._MSG_KEXDH_GEX_GROUP,), transport._expect) + + msg = Message() + msg.add_mpint(FakeModulusPack.P) + msg.add_mpint(FakeModulusPack.G) + msg.rewind() + kex.parse_next(paramiko.kex_gex._MSG_KEXDH_GEX_GROUP, msg) + x = b'20000000807E2DDB1743F3487D6545F04F1C8476092FB912B013626AB5BCEB764257D88BBA64243B9F348DF7B41B8C814A995E00299913503456983FFB9178D3CD79EB6D55522418A8ABF65375872E55938AB99A84A0B5FC8A1ECC66A7C3766E7E0F80B7CE2C9225FC2DD683F4764244B72963BBB383F529DCF0C5D17740B8A2ADBE9208D4' + self.assertEqual(x, hexlify(transport._message.asbytes()).upper()) + self.assertEqual((paramiko.kex_gex._MSG_KEXDH_GEX_REPLY,), transport._expect) + + msg = Message() + msg.add_string('fake-host-key') + msg.add_mpint(69) + msg.add_string('fake-sig') + msg.rewind() + kex.parse_next(paramiko.kex_gex._MSG_KEXDH_GEX_REPLY, msg) + H = b'AD1A9365A67B4496F05594AD1BF656E3CDA0851289A4C1AFF549FEAE50896DF4' + self.assertEqual(self.K, transport._K) + self.assertEqual(H, hexlify(transport._H).upper()) + self.assertEqual((b'fake-host-key', b'fake-sig'), transport._verify) + self.assertTrue(transport._activated) + + def test_8_gex_sha256_old_client(self): + transport = FakeTransport() + transport.server_mode = False + kex = KexGexSHA256(transport) + kex.start_kex(_test_old_style=True) + x = b'1E00000800' + self.assertEqual(x, hexlify(transport._message.asbytes()).upper()) + self.assertEqual((paramiko.kex_gex._MSG_KEXDH_GEX_GROUP,), transport._expect) + + msg = Message() + msg.add_mpint(FakeModulusPack.P) + msg.add_mpint(FakeModulusPack.G) + msg.rewind() + kex.parse_next(paramiko.kex_gex._MSG_KEXDH_GEX_GROUP, msg) + x = b'20000000807E2DDB1743F3487D6545F04F1C8476092FB912B013626AB5BCEB764257D88BBA64243B9F348DF7B41B8C814A995E00299913503456983FFB9178D3CD79EB6D55522418A8ABF65375872E55938AB99A84A0B5FC8A1ECC66A7C3766E7E0F80B7CE2C9225FC2DD683F4764244B72963BBB383F529DCF0C5D17740B8A2ADBE9208D4' + self.assertEqual(x, hexlify(transport._message.asbytes()).upper()) + self.assertEqual((paramiko.kex_gex._MSG_KEXDH_GEX_REPLY,), transport._expect) + + msg = Message() + msg.add_string('fake-host-key') + msg.add_mpint(69) + msg.add_string('fake-sig') + msg.rewind() + kex.parse_next(paramiko.kex_gex._MSG_KEXDH_GEX_REPLY, msg) + H = b'518386608B15891AE5237DEE08DCADDE76A0BCEFCE7F6DB3AD66BC41D256DFE5' + self.assertEqual(self.K, transport._K) + self.assertEqual(H, hexlify(transport._H).upper()) + self.assertEqual((b'fake-host-key', b'fake-sig'), transport._verify) + self.assertTrue(transport._activated) + + def test_9_gex_sha256_server(self): + transport = FakeTransport() + transport.server_mode = True + kex = KexGexSHA256(transport) + kex.start_kex() + self.assertEqual((paramiko.kex_gex._MSG_KEXDH_GEX_REQUEST, paramiko.kex_gex._MSG_KEXDH_GEX_REQUEST_OLD), transport._expect) + + msg = Message() + msg.add_int(1024) + msg.add_int(2048) + msg.add_int(4096) + msg.rewind() + kex.parse_next(paramiko.kex_gex._MSG_KEXDH_GEX_REQUEST, msg) + x = b'1F0000008100FFFFFFFFFFFFFFFFC90FDAA22168C234C4C6628B80DC1CD129024E088A67CC74020BBEA63B139B22514A08798E3404DDEF9519B3CD3A431B302B0A6DF25F14374FE1356D6D51C245E485B576625E7EC6F44C42E9A637ED6B0BFF5CB6F406B7EDEE386BFB5A899FA5AE9F24117C4B1FE649286651ECE65381FFFFFFFFFFFFFFFF0000000102' + self.assertEqual(x, hexlify(transport._message.asbytes()).upper()) + self.assertEqual((paramiko.kex_gex._MSG_KEXDH_GEX_INIT,), transport._expect) + + msg = Message() + msg.add_mpint(12345) + msg.rewind() + kex.parse_next(paramiko.kex_gex._MSG_KEXDH_GEX_INIT, msg) + K = 67592995013596137876033460028393339951879041140378510871612128162185209509220726296697886624612526735888348020498716482757677848959420073720160491114319163078862905400020959196386947926388406687288901564192071077389283980347784184487280885335302632305026248574716290537036069329724382811853044654824945750581 + H = b'CCAC0497CF0ABA1DBF55E1A3995D17F4CC31824B0E8D95CDF8A06F169D050D80' + x = b'210000000866616B652D6B6579000000807E2DDB1743F3487D6545F04F1C8476092FB912B013626AB5BCEB764257D88BBA64243B9F348DF7B41B8C814A995E00299913503456983FFB9178D3CD79EB6D55522418A8ABF65375872E55938AB99A84A0B5FC8A1ECC66A7C3766E7E0F80B7CE2C9225FC2DD683F4764244B72963BBB383F529DCF0C5D17740B8A2ADBE9208D40000000866616B652D736967' + self.assertEqual(K, transport._K) + self.assertEqual(H, hexlify(transport._H).upper()) + self.assertEqual(x, hexlify(transport._message.asbytes()).upper()) + self.assertTrue(transport._activated) + + def test_10_gex_sha256_server_with_old_client(self): + transport = FakeTransport() + transport.server_mode = True + kex = KexGexSHA256(transport) + kex.start_kex() + self.assertEqual((paramiko.kex_gex._MSG_KEXDH_GEX_REQUEST, paramiko.kex_gex._MSG_KEXDH_GEX_REQUEST_OLD), transport._expect) + + msg = Message() + msg.add_int(2048) + msg.rewind() + kex.parse_next(paramiko.kex_gex._MSG_KEXDH_GEX_REQUEST_OLD, msg) + x = b'1F0000008100FFFFFFFFFFFFFFFFC90FDAA22168C234C4C6628B80DC1CD129024E088A67CC74020BBEA63B139B22514A08798E3404DDEF9519B3CD3A431B302B0A6DF25F14374FE1356D6D51C245E485B576625E7EC6F44C42E9A637ED6B0BFF5CB6F406B7EDEE386BFB5A899FA5AE9F24117C4B1FE649286651ECE65381FFFFFFFFFFFFFFFF0000000102' + self.assertEqual(x, hexlify(transport._message.asbytes()).upper()) + self.assertEqual((paramiko.kex_gex._MSG_KEXDH_GEX_INIT,), transport._expect) + + msg = Message() + msg.add_mpint(12345) + msg.rewind() + kex.parse_next(paramiko.kex_gex._MSG_KEXDH_GEX_INIT, msg) + K = 67592995013596137876033460028393339951879041140378510871612128162185209509220726296697886624612526735888348020498716482757677848959420073720160491114319163078862905400020959196386947926388406687288901564192071077389283980347784184487280885335302632305026248574716290537036069329724382811853044654824945750581 + H = b'3DDD2AD840AD095E397BA4D0573972DC60F6461FD38A187CACA6615A5BC8ADBB' + x = b'210000000866616B652D6B6579000000807E2DDB1743F3487D6545F04F1C8476092FB912B013626AB5BCEB764257D88BBA64243B9F348DF7B41B8C814A995E00299913503456983FFB9178D3CD79EB6D55522418A8ABF65375872E55938AB99A84A0B5FC8A1ECC66A7C3766E7E0F80B7CE2C9225FC2DD683F4764244B72963BBB383F529DCF0C5D17740B8A2ADBE9208D40000000866616B652D736967' + self.assertEqual(K, transport._K) + self.assertEqual(H, hexlify(transport._H).upper()) + self.assertEqual(x, hexlify(transport._message.asbytes()).upper()) + self.assertTrue(transport._activated) + + diff --git a/tests/test_transport.py b/tests/test_transport.py index 50b1d86b..d6884e4b 100644 --- a/tests/test_transport.py +++ b/tests/test_transport.py @@ -28,6 +28,7 @@ import socket import time import threading import random +from hashlib import sha1 import unittest from paramiko import Transport, SecurityOptions, ServerInterface, RSAKey, DSSKey, \ @@ -447,9 +448,11 @@ class TransportTest(unittest.TestCase): bytes = self.tc.packetizer._Packetizer__sent_bytes chan.send('x' * 1024) bytes2 = self.tc.packetizer._Packetizer__sent_bytes + block_size = self.tc._cipher_info[self.tc.local_cipher]['block-size'] + mac_size = self.tc._mac_info[self.tc.local_mac]['size'] # tests show this is actually compressed to *52 bytes*! including packet overhead! nice!! :) self.assertTrue(bytes2 - bytes < 1024) - self.assertEqual(52, bytes2 - bytes) + self.assertEqual(16 + block_size + mac_size, bytes2 - bytes) chan.close() schan.close() |