From a6358f8d131b2c29babc82fc3d97cd3178d9638d Mon Sep 17 00:00:00 2001 From: Jeff Forcier Date: Wed, 16 May 2012 15:51:27 -0700 Subject: [PATCH] Merge #63 --- paramiko/packet.py | 20 +++++++++++++++----- 1 file changed, 15 insertions(+), 5 deletions(-) diff --git a/paramiko/packet.py b/paramiko/packet.py index 391c5d5..2f6d692 100644 --- a/paramiko/packet.py +++ b/paramiko/packet.py @@ -57,8 +57,11 @@ class Packetizer (object): # READ the secsh RFC's before raising these values. if anything, # they should probably be lower. - REKEY_PACKETS = pow(2, 30) - REKEY_BYTES = pow(2, 30) + REKEY_PACKETS = pow(2, 29) + REKEY_BYTES = pow(2, 29) + + REKEY_PACKETS_OVERFLOW_MAX = pow(2,29) # Allow receiving this many packets after a re-key request before terminating + REKEY_BYTES_OVERFLOW_MAX = pow(2,29) # Allow receiving this many bytes after a re-key request before terminating def __init__(self, socket): self.__socket = socket @@ -74,6 +77,7 @@ class Packetizer (object): self.__sent_packets = 0 self.__received_bytes = 0 self.__received_packets = 0 + self.__received_bytes_overflow = 0 self.__received_packets_overflow = 0 # current inbound/outbound ciphering: @@ -134,6 +138,7 @@ class Packetizer (object): self.__mac_key_in = mac_key self.__received_bytes = 0 self.__received_packets = 0 + self.__received_bytes_overflow = 0 self.__received_packets_overflow = 0 # wait until the reset happens in both directions before clearing rekey flag self.__init_count |= 2 @@ -316,6 +321,7 @@ class Packetizer (object): # only ask once for rekeying self._log(DEBUG, 'Rekeying (hit %d packets, %d bytes sent)' % (self.__sent_packets, self.__sent_bytes)) + self.__received_bytes_overflow = 0 self.__received_packets_overflow = 0 self._trigger_rekey() finally: @@ -368,19 +374,23 @@ class Packetizer (object): self.__sequence_number_in = (self.__sequence_number_in + 1) & 0xffffffffL # check for rekey - self.__received_bytes += packet_size + self.__mac_size_in + 4 + raw_packet_size = packet_size + self.__mac_size_in + 4 + self.__received_bytes += raw_packet_size self.__received_packets += 1 if self.__need_rekey: - # we've asked to rekey -- give them 20 packets to comply before + # we've asked to rekey -- give them some packets to comply before # dropping the connection + self.__received_bytes_overflow += raw_packet_size self.__received_packets_overflow += 1 - if self.__received_packets_overflow >= 20: + if (self.__received_packets_overflow >= self.REKEY_PACKETS_OVERFLOW_MAX) or \ + (self.__received_bytes_overflow >= self.REKEY_BYTES_OVERFLOW_MAX): raise SSHException('Remote transport is ignoring rekey requests') elif (self.__received_packets >= self.REKEY_PACKETS) or \ (self.__received_bytes >= self.REKEY_BYTES): # only ask once for rekeying self._log(DEBUG, 'Rekeying (hit %d packets, %d bytes received)' % (self.__received_packets, self.__received_bytes)) + self.__received_bytes_overflow = 0 self.__received_packets_overflow = 0 self._trigger_rekey()