[project @ Arch-1:robey@lag.net--2003-public%secsh--dev--1.0--patch-111]

fix extremely unlikely channel counter wrapping
Transport's channel counter can overflow after 4 billion some channels are
created.  make it wrap back around after 16 million instead.  also allow the
logging channel to be set manually.  fix some comments elsewhere.

3 files changed, 25 insertions, 11 deletions

diff --git a/paramiko/channel.py b/paramiko/channel.py
index 9b7384e3..b725a030 100644
--- a/paramiko/channel.py
+++ b/paramiko/channel.py
@@ -592,11 +592,6 @@ class Channel (object):
             self._send_eof()
 
 
-    ###  overrides
-
-
-
-
     ###  calls from Transport
 
 
diff --git a/paramiko/primes.py b/paramiko/primes.py
index 8c7e0a61..f3809950 100644
--- a/paramiko/primes.py
+++ b/paramiko/primes.py
@@ -29,7 +29,7 @@ import util
 def _generate_prime(bits, randpool):
     "primtive attempt at prime generation"
     hbyte_mask = pow(2, bits % 8) - 1
-    while 1:
+    while True:
         # loop catches the case where we increment n into a higher bit-range
         x = randpool.get_bytes((bits+7) // 8)
         if hbyte_mask > 0:
@@ -54,7 +54,7 @@ def _roll_random(randpool, n):
     # power of 2), we have slightly better than 50% odds of getting one that
     # fits, so i can't guarantee that this loop will ever finish, but the odds
     # of it looping forever should be infinitesimal.
-    while 1:
+    while True:
         x = randpool.get_bytes(bytes)
         if hbyte_mask > 0:
             x = chr(ord(x[0]) & hbyte_mask) + x[1:]
diff --git a/paramiko/transport.py b/paramiko/transport.py
index 678cb6dc..0eb9c7c0 100644
--- a/paramiko/transport.py
+++ b/paramiko/transport.py
@@ -511,10 +511,13 @@ class BaseTransport (threading.Thread):
         if not self.active:
             # don't bother trying to allocate a channel
             return None
+        self.lock.acquire()
         try:
-            self.lock.acquire()
             chanid = self.channel_counter
-            self.channel_counter += 1
+            while self.channels.has_key(chanid):
+                self.channel_counter = (self.channel_counter + 1) & 0xffffff
+                chanid = self.channel_counter
+            self.channel_counter = (self.channel_counter + 1) & 0xffffff
             m = Message()
             m.add_byte(chr(MSG_CHANNEL_OPEN))
             m.add_string(kind)
@@ -800,6 +803,19 @@ class BaseTransport (threading.Thread):
         finally:
             self.lock.release()
 
+    def set_log_channel(self, name):
+        """
+        Set the channel for this transport's logging.  The default is
+        C{"paramiko.transport"} but it can be set to anything you want.
+        (See the C{logging} module for more info.)
+
+        @param name: new channel name for logging.
+        @type name: str
+
+        @since: 1.1
+        """
+        self.logger = logging.getLogger(name)
+
 
     ###  internals...
 
@@ -1437,10 +1453,13 @@ class BaseTransport (threading.Thread):
             reject = True
             reason = OPEN_FAILED_ADMINISTRATIVELY_PROHIBITED
         else:
+            self.lock.acquire()
             try:
-                self.lock.acquire()
                 my_chanid = self.channel_counter
-                self.channel_counter += 1
+                while self.channels.has_key(my_chanid):
+                    self.channel_counter = (self.channel_counter + 1) & 0xffffff
+                    my_chanid = self.channel_counter
+                self.channel_counter = (self.channel_counter + 1) & 0xffffff
             finally:
                 self.lock.release()
             reason = self.server_object.check_channel_request(kind, my_chanid)