Files
chipsec-chipsec/chipsec/modules/common/remap.py
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brentholtsclaw f7fe1be074 More whitespace cleanup
E231, E201, E226

Signed-off-by: brentholtsclaw <brent.holtsclaw@intel.com>
2020-07-31 13:46:13 -07:00

149 lines
6.4 KiB
Python

#CHIPSEC: Platform Security Assessment Framework
#Copyright (c) 2010-2020, Intel Corporation
#
#This program is free software; you can redistribute it and/or
#modify it under the terms of the GNU General Public License
#as published by the Free Software Foundation; Version 2.
#
#This program is distributed in the hope that it will be useful,
#but WITHOUT ANY WARRANTY; without even the implied warranty of
#MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
#GNU General Public License for more details.
#
#You should have received a copy of the GNU General Public License
#along with this program; if not, write to the Free Software
#Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
#
#Contact information:
#chipsec@intel.com
#
"""
`Preventing & Detecting Xen Hypervisor Subversions <http://www.invisiblethingslab.com/resources/bh08/part2-full.pdf>`_ by Joanna Rutkowska & Rafal Wojtczuk
Check Memory Remapping Configuration
"""
from chipsec.module_common import BaseModule, ModuleResult, MTAG_HWCONFIG, MTAG_SMM
from chipsec.defines import BIT32, ALIGNED_1MB
_MODULE_NAME = 'remap'
TAGS = [MTAG_SMM, MTAG_HWCONFIG]
_REMAP_ADDR_MASK = 0x7FFFF00000
_TOLUD_MASK = 0xFFFFF000
class remap(BaseModule):
def __init__(self):
BaseModule.__init__(self)
def is_supported(self):
if self.cs.is_core():
return True
self.res = ModuleResult.NOTAPPLICABLE
return False
def check_remap_config(self):
self.logger.start_test( "Memory Remapping Configuration" )
if not self.cs.is_register_defined( 'PCI0.0.0_REMAPBASE' ) or \
not self.cs.is_register_defined( 'PCI0.0.0_REMAPLIMIT' ) or \
not self.cs.is_register_defined( 'PCI0.0.0_TOUUD' ) or \
not self.cs.is_register_defined( 'PCI0.0.0_TOLUD' ) or \
not self.cs.is_register_defined( 'PCI0.0.0_TSEGMB' ):
self.logger.error( "Couldn't find definition of required registers (REMAP*, TOLUD, TOUUD, TSEGMB)" )
return ModuleResult.ERROR
remapbase = self.cs.read_register( 'PCI0.0.0_REMAPBASE' )
remaplimit = self.cs.read_register( 'PCI0.0.0_REMAPLIMIT' )
touud = self.cs.read_register( 'PCI0.0.0_TOUUD' )
tolud = self.cs.read_register( 'PCI0.0.0_TOLUD' )
tsegmb = self.cs.read_register( 'PCI0.0.0_TSEGMB' )
self.logger.log( "[*] Registers:" )
self.logger.log( "[*] TOUUD : 0x{:016X}".format(touud) )
self.logger.log( "[*] REMAPLIMIT: 0x{:016X}".format(remaplimit) )
self.logger.log( "[*] REMAPBASE : 0x{:016X}".format(remapbase) )
self.logger.log( "[*] TOLUD : 0x{:08X}".format(tolud) )
self.logger.log( "[*] TSEGMB : 0x{:08X}\n".format(tsegmb) )
ia_untrusted = 0
if self.cs.is_register_defined('MSR_BIOS_DONE') and self.cs.register_has_field('MSR_BIOS_DONE', 'IA_UNTRUSTED'):
ia_untrusted = self.cs.read_register_field('MSR_BIOS_DONE', 'IA_UNTRUSTED')
remapbase_lock = remapbase & 0x1
remaplimit_lock = remaplimit & 0x1
touud_lock = touud & 0x1
tolud_lock = tolud & 0x1
tsegmb_lock = tsegmb & 0x1
remapbase &= _REMAP_ADDR_MASK
remaplimit &= _REMAP_ADDR_MASK
#remaplimit |= 0xFFFFF
touud &= _REMAP_ADDR_MASK
tolud &= _TOLUD_MASK
tsegmb &= _TOLUD_MASK
self.logger.log( "[*] Memory Map:" )
self.logger.log( "[*] Top Of Upper Memory: 0x{:016X}".format(touud) )
self.logger.log( "[*] Remap Limit Address: 0x{:016X}".format(remaplimit|0xFFFFF) )
self.logger.log( "[*] Remap Base Address : 0x{:016X}".format(remapbase) )
self.logger.log( "[*] 4GB : 0x{:016X}".format(BIT32) )
self.logger.log( "[*] Top Of Low Memory : 0x{:016X}".format(tolud) )
self.logger.log( "[*] TSEG (SMRAM) Base : 0x{:016X}\n".format(tsegmb) )
remap_ok = True
self.logger.log( "[*] checking memory remap configuration.." )
if remapbase > remaplimit:
self.logger.log( "[*] Memory Remap is disabled" )
else:
self.logger.log( "[*] Memory Remap is enabled" )
remaplimit_addr = (remaplimit|0xFFFFF)
ok = ((remaplimit_addr + 1) == touud)
remap_ok = remap_ok and ok
if ok: self.logger.log_good( " Remap window configuration is correct: REMAPBASE <= REMAPLIMIT < TOUUD" )
else: self.logger.log_bad( " Remap window configuration is not correct" )
ok = (0 == tolud & ALIGNED_1MB) and \
(0 == touud & ALIGNED_1MB) and \
(0 == remapbase & ALIGNED_1MB) and \
(0 == remaplimit & ALIGNED_1MB)
remap_ok = remap_ok and ok
if ok: self.logger.log_good( " All addresses are 1MB aligned" )
else: self.logger.log_bad( " Not all addresses are 1MB aligned" )
self.logger.log( "[*] checking if memory remap configuration is locked.." )
ok = (0 != touud_lock) or (0 != ia_untrusted)
remap_ok = remap_ok and ok
if ok: self.logger.log_good( " TOUUD is locked" )
else: self.logger.log_bad( " TOUUD is not locked" )
ok = (0 != tolud_lock) or (0 != ia_untrusted)
remap_ok = remap_ok and ok
if ok: self.logger.log_good( " TOLUD is locked" )
else: self.logger.log_bad( " TOLUD is not locked" )
ok = ((0 != remapbase_lock) and (0 != remaplimit_lock)) or (0 != ia_untrusted)
remap_ok = remap_ok and ok
if ok: self.logger.log_good( " REMAPBASE and REMAPLIMIT are locked" )
else: self.logger.log_bad( " REMAPBASE and REMAPLIMIT are not locked" )
if remap_ok:
res = ModuleResult.PASSED
self.logger.log_passed_check( "Memory Remap is configured correctly and locked" )
else:
res = ModuleResult.FAILED
self.logger.log_failed_check( "Memory Remap is not properly configured/locked. Remaping attack may be possible" )
return res
# --------------------------------------------------------------------------
# run( module_argv )
# Required function: run here all tests from this module
# --------------------------------------------------------------------------
def run( self, module_argv ):
self.res = self.check_remap_config()
return self.res