[project @ Arch-1:robey@lag.net--2003-public%secsh--dev--1.0--patch-107]

fix kex_gex
fix kex_gex (group-exchange key exchange) to, *cough*, work again, and also
layout kex_group1 a little more sanely.

paramiko/kex_gex.py

@@ -72,6 +72,10 @@ class KexGex (object):
             return self._parse_kexdh_gex_reply(m)
         raise SSHException('KexGex asked to handle packet type %d' % ptype)
 
+
+    ###  internals...
+
+    
     def _generate_x(self):
         # generate an "x" (1 < x < (p-1)/2).
         q = (self.p - 1) // 2
@@ -82,7 +86,7 @@ class KexGex (object):
         while not (qhbyte & 0x80):
             qhbyte <<= 1
             qmask >>= 1
-        while 1:
+        while True:
             self.transport.randpool.stir()
             x_bytes = self.transport.randpool.get_bytes(bytes)
             x_bytes = chr(ord(x_bytes[0]) & qmask) + x_bytes[1:]
@@ -152,8 +156,15 @@ class KexGex (object):
         hm = Message()
         hm.add(self.transport.remote_version, self.transport.local_version,
                self.transport.remote_kex_init, self.transport.local_kex_init,
-               key, self.min_bits, self.preferred_bits, self.max_bits,
+               key)
-               self.p, self.g, self.e, self.f, K)
+        hm.add_int(self.min_bits)
+        hm.add_int(self.preferred_bits)
+        hm.add_int(self.max_bits)
+        hm.add_mpint(self.p)
+        hm.add_mpint(self.g)
+        hm.add_mpint(self.e)
+        hm.add_mpint(self.f)
+        hm.add_mpint(K)
         H = SHA.new(str(hm)).digest()
         self.transport._set_K_H(K, H)
         # sign it
@@ -178,8 +189,15 @@ class KexGex (object):
         hm = Message()
         hm.add(self.transport.local_version, self.transport.remote_version,
                self.transport.local_kex_init, self.transport.remote_kex_init,
-               host_key, self.min_bits, self.preferred_bits, self.max_bits,
+               host_key)
-               self.p, self.g, self.e, self.f, K)
+        hm.add_int(self.min_bits)
+        hm.add_int(self.preferred_bits)
+        hm.add_int(self.max_bits)
+        hm.add_mpint(self.p)
+        hm.add_mpint(self.g)
+        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._verify_key(host_key, sig)
         self.transport._activate_outbound()

paramiko/kex_group1.py

@@ -44,23 +44,8 @@ class KexGroup1(object):
     def __init__(self, transport):
         self.transport = transport
 
-    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. 
-        # therefore q can be approximated as a 2^1023.  we drop the subset of
-        # 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:
-            self.transport.randpool.stir()
-            x_bytes = self.transport.randpool.get_bytes(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'):
-                break
-        self.x = util.inflate_long(x_bytes)
-
     def start_kex(self):
-        self.generate_x()
+        self._generate_x()
         if self.transport.server_mode:
             # compute f = g^x mod p, but don't send it yet
             self.f = pow(G, self.x, P)
@@ -76,12 +61,31 @@ class KexGroup1(object):
 
     def parse_next(self, ptype, m):
         if self.transport.server_mode and (ptype == _MSG_KEXDH_INIT):
-            return self.parse_kexdh_init(m)
+            return self._parse_kexdh_init(m)
         elif not self.transport.server_mode and (ptype == _MSG_KEXDH_REPLY):
-            return self.parse_kexdh_reply(m)
+            return self._parse_kexdh_reply(m)
         raise SSHException('KexGroup1 asked to handle packet type %d' % ptype)
+    
 
-    def parse_kexdh_reply(self, m):
+    ###  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. 
+        # therefore q can be approximated as a 2^1023.  we drop the subset of
+        # 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:
+            self.transport.randpool.stir()
+            x_bytes = self.transport.randpool.get_bytes(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'):
+                break
+        self.x = util.inflate_long(x_bytes)
+
+    def _parse_kexdh_reply(self, m):
         # client mode
         host_key = m.get_string()
         self.f = m.get_mpint()
@@ -98,7 +102,7 @@ class KexGroup1(object):
         self.transport._verify_key(host_key, sig)
         self.transport._activate_outbound()
 
-    def parse_kexdh_init(self, m):
+    def _parse_kexdh_init(self, m):
         # server mode
         self.e = m.get_mpint()
         if (self.e < 1) or (self.e > P - 1):