diff options
Diffstat (limited to 'paramiko/dsskey.py')
| -rw-r--r-- | paramiko/dsskey.py | 68 |
1 files changed, 35 insertions, 33 deletions
diff --git a/paramiko/dsskey.py b/paramiko/dsskey.py index f6ecb2a..1901596 100644 --- a/paramiko/dsskey.py +++ b/paramiko/dsskey.py @@ -17,14 +17,17 @@ # 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. """ -L{DSSKey} +DSS keys. """ +import os +from hashlib import sha1 + from Crypto.PublicKey import DSA -from Crypto.Hash import SHA -from paramiko.common import * from paramiko import util +from paramiko.common import zero_byte +from paramiko.py3compat import long from paramiko.ssh_exception import SSHException from paramiko.message import Message from paramiko.ber import BER, BERException @@ -56,7 +59,7 @@ class DSSKey (PKey): else: if msg is None: raise SSHException('Key object may not be empty') - if msg.get_string() != 'ssh-dss': + if msg.get_text() != 'ssh-dss': raise SSHException('Invalid key') self.p = msg.get_mpint() self.q = msg.get_mpint() @@ -64,14 +67,17 @@ class DSSKey (PKey): self.y = msg.get_mpint() self.size = util.bit_length(self.p) - def __str__(self): + def asbytes(self): m = Message() m.add_string('ssh-dss') m.add_mpint(self.p) m.add_mpint(self.q) m.add_mpint(self.g) m.add_mpint(self.y) - return str(m) + return m.asbytes() + + def __str__(self): + return self.asbytes() def __hash__(self): h = hash(self.get_name()) @@ -87,17 +93,17 @@ class DSSKey (PKey): def get_bits(self): return self.size - + def can_sign(self): return self.x is not None - def sign_ssh_data(self, rng, data): - digest = SHA.new(data).digest() + def sign_ssh_data(self, data): + digest = sha1(data).digest() dss = DSA.construct((long(self.y), long(self.g), long(self.p), long(self.q), long(self.x))) # generate a suitable k qsize = len(util.deflate_long(self.q, 0)) while True: - k = util.inflate_long(rng.read(qsize), 1) + k = util.inflate_long(os.urandom(qsize), 1) if (k > 2) and (k < self.q): break r, s = dss.sign(util.inflate_long(digest, 1), k) @@ -107,26 +113,26 @@ class DSSKey (PKey): rstr = util.deflate_long(r, 0) sstr = util.deflate_long(s, 0) if len(rstr) < 20: - rstr = '\x00' * (20 - len(rstr)) + rstr + rstr = zero_byte * (20 - len(rstr)) + rstr if len(sstr) < 20: - sstr = '\x00' * (20 - len(sstr)) + sstr + sstr = zero_byte * (20 - len(sstr)) + sstr m.add_string(rstr + sstr) return m def verify_ssh_sig(self, data, msg): - if len(str(msg)) == 40: + if len(msg.asbytes()) == 40: # spies.com bug: signature has no header - sig = str(msg) + sig = msg.asbytes() else: - kind = msg.get_string() + kind = msg.get_text() if kind != 'ssh-dss': return 0 - sig = msg.get_string() + sig = msg.get_binary() # pull out (r, s) which are NOT encoded as mpints sigR = util.inflate_long(sig[:20], 1) sigS = util.inflate_long(sig[20:], 1) - sigM = util.inflate_long(SHA.new(data).digest(), 1) + sigM = util.inflate_long(sha1(data).digest(), 1) dss = DSA.construct((long(self.y), long(self.g), long(self.p), long(self.q))) return dss.verify(sigM, (sigR, sigS)) @@ -134,13 +140,13 @@ class DSSKey (PKey): def _encode_key(self): if self.x is None: raise SSHException('Not enough key information') - keylist = [ 0, self.p, self.q, self.g, self.y, self.x ] + keylist = [0, self.p, self.q, self.g, self.y, self.x] try: b = BER() b.encode(keylist) except BERException: raise SSHException('Unable to create ber encoding of key') - return str(b) + return b.asbytes() def write_private_key_file(self, filename, password=None): self._write_private_key_file('DSA', filename, self._encode_key(), password) @@ -153,39 +159,35 @@ class DSSKey (PKey): Generate a new private DSS key. This factory function can be used to generate a new host key or authentication key. - @param bits: number of bits the generated key should be. - @type bits: int - @param progress_func: an optional function to call at key points in - key generation (used by C{pyCrypto.PublicKey}). - @type progress_func: function - @return: new private key - @rtype: L{DSSKey} + :param int bits: number of bits the generated key should be. + :param function progress_func: + an optional function to call at key points in key generation (used + by ``pyCrypto.PublicKey``). + :return: new `.DSSKey` private key """ - dsa = DSA.generate(bits, rng.read, progress_func) + dsa = DSA.generate(bits, os.urandom, progress_func) key = DSSKey(vals=(dsa.p, dsa.q, dsa.g, dsa.y)) key.x = dsa.x return key generate = staticmethod(generate) - ### internals... - def _from_private_key_file(self, filename, password): data = self._read_private_key_file('DSA', filename, password) self._decode_key(data) - + def _from_private_key(self, file_obj, password): data = self._read_private_key('DSA', file_obj, password) self._decode_key(data) - + def _decode_key(self, data): # private key file contains: # DSAPrivateKey = { version = 0, p, q, g, y, x } try: keylist = BER(data).decode() - except BERException, x: - raise SSHException('Unable to parse key file: ' + str(x)) + except BERException as e: + raise SSHException('Unable to parse key file: ' + str(e)) if (type(keylist) is not list) or (len(keylist) < 6) or (keylist[0] != 0): raise SSHException('not a valid DSA private key file (bad ber encoding)') self.p = keylist[1] |