diff options
Diffstat (limited to 'paramiko/kex_group1.py')
| -rw-r--r-- | paramiko/kex_group1.py | 44 |
1 files changed, 24 insertions, 20 deletions
diff --git a/paramiko/kex_group1.py b/paramiko/kex_group1.py index 6e89b6d..7ccceea 100644 --- a/paramiko/kex_group1.py +++ b/paramiko/kex_group1.py @@ -21,20 +21,26 @@ Standard SSH key exchange ("kex" if you wanna sound cool). Diffie-Hellman of 1024 bit key halves, using a known "p" prime and "g" generator. """ -from Crypto.Hash import SHA +import os +from hashlib import sha1 -from paramiko.common import * from paramiko import util +from paramiko.common import max_byte, zero_byte from paramiko.message import Message +from paramiko.py3compat import byte_chr, long, byte_mask from paramiko.ssh_exception import SSHException _MSG_KEXDH_INIT, _MSG_KEXDH_REPLY = range(30, 32) +c_MSG_KEXDH_INIT, c_MSG_KEXDH_REPLY = [byte_chr(c) for c in range(30, 32)] # draft-ietf-secsh-transport-09.txt, page 17 -P = 0xFFFFFFFFFFFFFFFFC90FDAA22168C234C4C6628B80DC1CD129024E088A67CC74020BBEA63B139B22514A08798E3404DDEF9519B3CD3A431B302B0A6DF25F14374FE1356D6D51C245E485B576625E7EC6F44C42E9A637ED6B0BFF5CB6F406B7EDEE386BFB5A899FA5AE9F24117C4B1FE649286651ECE65381FFFFFFFFFFFFFFFFL +P = 0xFFFFFFFFFFFFFFFFC90FDAA22168C234C4C6628B80DC1CD129024E088A67CC74020BBEA63B139B22514A08798E3404DDEF9519B3CD3A431B302B0A6DF25F14374FE1356D6D51C245E485B576625E7EC6F44C42E9A637ED6B0BFF5CB6F406B7EDEE386BFB5A899FA5AE9F24117C4B1FE649286651ECE65381FFFFFFFFFFFFFFFF G = 2 +b7fffffffffffffff = byte_chr(0x7f) + max_byte * 7 +b0000000000000000 = zero_byte * 8 + class KexGroup1(object): @@ -42,9 +48,9 @@ class KexGroup1(object): def __init__(self, transport): self.transport = transport - self.x = 0L - self.e = 0L - self.f = 0L + self.x = long(0) + self.e = long(0) + self.f = long(0) def start_kex(self): self._generate_x() @@ -56,7 +62,7 @@ class KexGroup1(object): # compute e = g^x mod p (where g=2), and send it self.e = pow(G, self.x, P) m = Message() - m.add_byte(chr(_MSG_KEXDH_INIT)) + m.add_byte(c_MSG_KEXDH_INIT) m.add_mpint(self.e) self.transport._send_message(m) self.transport._expect_packet(_MSG_KEXDH_REPLY) @@ -67,11 +73,9 @@ class KexGroup1(object): elif not self.transport.server_mode and (ptype == _MSG_KEXDH_REPLY): return self._parse_kexdh_reply(m) raise SSHException('KexGroup1 asked to handle packet type %d' % ptype) - ### internals... - def _generate_x(self): # generate an "x" (1 < x < q), where q is (p-1)/2. # p is a 128-byte (1024-bit) number, where the first 64 bits are 1. @@ -79,10 +83,10 @@ class KexGroup1(object): # potential x where the first 63 bits are 1, because some of those will be # larger than q (but this is a tiny tiny subset of potential x). while 1: - x_bytes = self.transport.rng.read(128) - x_bytes = chr(ord(x_bytes[0]) & 0x7f) + x_bytes[1:] - if (x_bytes[:8] != '\x7F\xFF\xFF\xFF\xFF\xFF\xFF\xFF') and \ - (x_bytes[:8] != '\x00\x00\x00\x00\x00\x00\x00\x00'): + x_bytes = os.urandom(128) + x_bytes = byte_mask(x_bytes[0], 0x7f) + x_bytes[1:] + if (x_bytes[:8] != b7fffffffffffffff and + x_bytes[:8] != b0000000000000000): break self.x = util.inflate_long(x_bytes) @@ -92,7 +96,7 @@ class KexGroup1(object): self.f = m.get_mpint() if (self.f < 1) or (self.f > P - 1): raise SSHException('Server kex "f" is out of range') - sig = m.get_string() + sig = m.get_binary() K = pow(self.f, self.x, P) # okay, build up the hash H of (V_C || V_S || I_C || I_S || K_S || e || f || K) hm = Message() @@ -102,7 +106,7 @@ class KexGroup1(object): hm.add_mpint(self.e) hm.add_mpint(self.f) hm.add_mpint(K) - self.transport._set_K_H(K, SHA.new(str(hm)).digest()) + self.transport._set_K_H(K, sha1(hm.asbytes()).digest()) self.transport._verify_key(host_key, sig) self.transport._activate_outbound() @@ -112,7 +116,7 @@ class KexGroup1(object): if (self.e < 1) or (self.e > P - 1): raise SSHException('Client kex "e" is out of range') K = pow(self.e, self.x, P) - key = str(self.transport.get_server_key()) + key = self.transport.get_server_key().asbytes() # okay, build up the hash H of (V_C || V_S || I_C || I_S || K_S || e || f || K) hm = Message() hm.add(self.transport.remote_version, self.transport.local_version, @@ -121,15 +125,15 @@ class KexGroup1(object): hm.add_mpint(self.e) hm.add_mpint(self.f) hm.add_mpint(K) - H = SHA.new(str(hm)).digest() + H = sha1(hm.asbytes()).digest() self.transport._set_K_H(K, H) # sign it - sig = self.transport.get_server_key().sign_ssh_data(self.transport.rng, H) + sig = self.transport.get_server_key().sign_ssh_data(H) # send reply m = Message() - m.add_byte(chr(_MSG_KEXDH_REPLY)) + m.add_byte(c_MSG_KEXDH_REPLY) m.add_string(key) m.add_mpint(self.f) - m.add_string(str(sig)) + m.add_string(sig) self.transport._send_message(m) self.transport._activate_outbound() |