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unpack.py
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unpack.py
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##############################################################
# Python script to attempt automatic unpacking/decrypting of #
# malware samples using WinAppDbg. #
# #
# unpack.py v2016.01.25 #
# http://malwaremusings.com/scripts/unpack.py #
##############################################################
import sys
import traceback
import winappdbg
import time
import struct
import ctypes
# Log file which we log info to
logfile = None
class MyEventHandler(winappdbg.EventHandler):
###
# A. Declaring variables
###
# A.1 used to keep track of allocated executable memory
allocedmem = {}
# A.2 used to indicate that we've found the entry point
entrypt = 0x00000000
#
# variables used to find and disassemble unpacking loop
#
# A.3 used to indicate that we're single stepping
tracing = -1
# A.4 remember the last two eip values
lasteip = [0x00000000,0x00000000]
# A.5 lowest eip address we see
lowesteip = 0xffffffff
# A.6 highest eip address we see
highesteip = 0x00000000
# A.7 list of addresses which we've disassembled
disasmd = []
# A.8 keeps track of addresses and instructions
# that write to the allocated memory block(s)
writeaddrs = {}
#
# variables used to keep track of created processes
#
# A.9 keeps track of created processes to map
# hProcess from WriteProcessMemory() back to
# process name
createdprocesses = {}
# A.10 keeps track of processes that were created
# with the CREATE_SUSPENDED flag set
createsuspended = {}
#
# variables used for logging
#
# A.11 used to keep a log of events
eventlog = []
###
# B. Class methods (functions)
###
### B.1
# get_funcargs(event)
# query winappdbg to get the function arguments
#
# return a tuple consisting of the return address
# and a sub-tuple of function arguments
###
def get_funcargs(self,event):
h = event.hook
t = event.get_thread()
tid = event.get_tid()
return (t.get_pc(),h.get_params(tid))
### B.2
# guarded_read(d,t,addr,size)
# read memory after checking for, and if necessary,
# disabling memory breakpoints
#
# returns a string of data
###
def guarded_read(self,d,t,addr,size):
# keep track of breakpoints that we disabled
# so that we can enable them again after we've
# finished
reenablebps = []
# initialise the variable to hold the read
# memory data
data = ""
# check that the requested size is sane
if (size > 0):
p = t.get_process()
# check to see if the requested address falls within
# any of the existing memory breakpoints by checking
# if either the requested start address or end address
# is covered by any breakpoint
mem_bps = d.get_all_page_breakpoints()
for (pid,pgbp) in mem_bps:
(startaddr,endaddr) = pgbp.get_span()
if (pid == p.get_pid()) and (pgbp.is_here(addr) or pgbp.is_here(addr + size - 1)):
log("[D] Memory read in guarded memory. Disabling breakpoint: %s" % pgbp)
pgbp.disable(p,t)
reenablebps.append(pgbp)
# read the memory
data = p.read(addr,size)
# enable all of the breakpoints that we disabled
if (len(reenablebps) > 0):
for pgbp in reenablebps:
log("[D] Re-enabling breakpoint: %s" % pgbp)
pgbp.enable(p,t)
# return the read memory as a string
return data
###
# C. API Hooks
###
### C.1
# apiHooks: winappdbg defined hash of API calls to hook
#
# Each entry is indexed by library name and is an array of
# tuples consisting of API call name and number of args
###
apiHooks = {
"kernel32.dll":[
("VirtualAlloc",4),
("VirtualAllocEx",5),
("IsDebuggerPresent",0),
("CreateProcessA",10),
("CreateProcessW",10),
("WriteProcessMemory",5)
],
"advapi32.dll":[
("CryptDecrypt",6)
],
"wininet.dll":[
("InternetOpenA",5),
("InternetOpenW",5)
],
"ntdll.dll":[
("RtlDecompressBuffer",6)
],
"secur32.dll":[
("EncryptMessage",4),
("DecryptMessage",4)
]
}
###
# API hook callback functions
#
# These are defined by winappdbg and consist of functions
# named pre_<apifuncname> and post_<apifuncname> which are
# called on entry to, and on exit from, the given API
# function (<apifuncname>), respectively.
###
# C.2
# VirtualAlloc() hook(s)
#
def post_VirtualAllocEx(self,event,retval):
try:
# C.2.1 Get the return address and arguments
(ra,(hProcess,lpAddress,dwSize,flAllocationType,flProtect)) = self.get_funcargs(event)
# Get an instance to the debugger which triggered the event
# and also the process id and thread id of the process to which
# the event pertains
d = event.debug
pid = event.get_pid()
tid = event.get_tid()
# Log the fact that we've seen a VirtualAllocEx() call
log("[*] <%d:%d> 0x%x: VirtualAllocEx(0x%x,0x%x,0x%x (%d),0x%x,0x%03x) = 0x%x" % (pid,tid,ra,hProcess,lpAddress,dwSize,dwSize,flAllocationType,flProtect,retval))
# C.2.2 All the memory protection bits which include EXECUTE
# permission use bits 4 - 7, which is nicely matched
# by masking (ANDing) it with 0xf0 and checking for a
# non-zero result
if (flProtect & 0x0f0):
log("[-] Request for EXECUTEable memory")
# We can only set page guards on our own process
# otherwise page guard exception will occur in
# system code when this process attempts to write
# to the allocated memory.
# This causes ZwWriteVirtualMemory() to fail
# We can, however, set a page guard on it when
# this process creates the remote thread, as it
# will have presumably stopped writing to the
# other process' memory at that point.
# C.2.2.1 Check that this VirtualAllocEx() call is for
# the current process (hProcess == -1), and if
# so, ask the winappdbg debugger instance to
# create a page guard on the memory region.
# Also add information about the allocated region
# to our allocedmem hash, indexed by pid and
# base address.
if (hProcess == 0xffffffff):
d.watch_buffer(pid,retval,dwSize - 1,self.guard_page_exemem)
self.allocedmem[(pid,retval)] = dwSize
# C.2.3 Create a JSON event log entry
self.eventlog.append({
"time": time.time(),
"name": "VirtualAllocEx",
"type": "Win32 API",
"pid": pid,
"tid": tid,
"addr": ra,
"args": {
"hProcess": hProcess,
"lpAddress": lpAddress,
"dwSize": dwSize,
"flAllocationType": flAllocationType,
"flProtect": flProtect
},
"ret": retval
})
except:
traceback.print_exc()
raise
def post_VirtualAlloc(self,event,retval):
try:
# C.2.4 Get the return address and arguments
(ra,(lpAddress,dwSize,flAllocationType,flProtect)) = self.get_funcargs(event)
# Get an instance to the debugger which triggered the event
# and also the process id and thread id of the process to which
# the event pertains
d = event.debug
pid = event.get_pid()
tid = event.get_tid()
# Log the fact that we've seen a VirtualAlloc() call
# This is so that we get the address in the debuggee code from which it was called
# where as if we just let the VirtualAllocEx() hook log it, the address from
# which it was called is inside the VirtualAlloc() code in kernel32.dll
log("[*] <%d:%d> 0x%x: VirtualAlloc(0x%x,0x%x (%d),0x%x,0x%03x) = 0x%x" % (pid,tid,ra,lpAddress,dwSize,dwSize,flAllocationType,flProtect,retval))
# C.2.5 Create a JSON event log entry
self.eventlog.append({
"time": time.time(),
"name": "VirtualAlloc",
"type": "Win32 API",
"pid": pid,
"tid": tid,
"addr": ra,
"args": {
"lpAddress": lpAddress,
"dwSize": dwSize,
"flAllocationType": flAllocationType,
"flProtect": flProtect
},
"ret": retval
})
except:
traceback.print_exc()
raise
# C.3
# CryptDecrypt() hook(s)
#
def pre_CryptDecrypt(self,event,*args):
# C.3.1 Get the return address and arguments
(ra,hKey,hHash,Final,dwFlags,pbData,pdwDataLen) = (args[0],args[1],args[2],args[3],args[4],args[5],args[6])
# C.3.2 Get a Process object and dereference the pdwDataLen argument to read the buffer size
p = event.get_process()
buffsize = p.read_uint(pdwDataLen)
# C.3.3 Save a copy of the encrypted data
filename = "%s.memblk0x%x.enc" % (sys.argv[1],pbData)
log("[-] Dumping %d bytes of encrypted memory at 0x%x to %s" % (buffsize,pbData,filename))
databuff = open(filename,"wb")
databuff.write(p.read(pbData,buffsize));
databuff.close()
def post_CryptDecrypt(self,event,retval):
# C.3.4 Get the return address and arguments
(ra,(hKey,hHash,Final,dwFlags,pbData,pdwDataLen)) = self.get_funcargs(event)
# Get a Process object, and dereference the pdwDataLen argument
p = event.get_process()
buffsize = p.read_uint(pdwDataLen)
pid = event.get_pid()
tid = event.get_tid()
log("[*] <%d:%d> 0x%x: CryptDecrypt(0x%x,0x%x,0x%x,0x%x,0x%x,0x%x (%d)) = %d" % (pid,tid,ra,hKey,hHash,Final,dwFlags,pbData,buffsize,buffsize,retval))
# C.3.5 Save a copy of the decrypted data
filename_enc = "%s.memblk0x%x.enc" % (sys.argv[1],pbData)
filename = "%s.memblk0x%x.dec" % (sys.argv[1],pbData)
log("[-] Dumping %d bytes of decrypted memory at 0x%x to %s" % (buffsize,pbData,filename))
databuff = open(filename,"wb")
databuff.write(p.read(pbData,buffsize))
databuff.close()
# C.3.6 Create a JSON event log entry
pid = event.get_pid()
tid = event.get_tid()
self.eventlog.append({
"time": time.time(),
"name": "CryptDecrypt",
"type": "Win32 API",
"pid": pid,
"tid": tid,
"addr": ra,
"args": {
"hKey": hKey,
"hHash": hHash,
"Final": Final,
"dwFlags": dwFlags,
"pbData": pdwDataLen
},
"ret": retval,
"info": {
"filename_enc": filename_enc,
"filename_dec": filename
}
})
# C.4
# RtlDecompressBuffer() hook(s)
#
def pre_RtlDecompressBuffer(self,event,*args):
try:
# C.4.1 Get the return address and arguments
(ra,CompressionFormat,UncompressedBuffer,UncompressedBufferSize,CompressedBuffer,CompressedBufferSize,FinalUncompressedSize) = (args[0],args[1],args[2],args[3],args[4],args[5],args[6])
p = event.get_process()
# C.4.2 Save a copy of the compressed data
filename = "%s.memblk0x%x.comp" % (sys.argv[1],CompressedBuffer)
log("[-] Dumping %d bytes of compressed memory at 0x%x to %s" % (CompressedBufferSize,CompressedBuffer,filename))
databuff = open(filename,"wb")
databuff.write(p.read(CompressedBuffer,CompressedBufferSize));
databuff.close()
except:
traceback.print_exc()
raise
def post_RtlDecompressBuffer(self,event,retval):
try:
# C.4.3 Get the return address and arguments
(ra,(CompressionFormat,UncompressedBuffer,UncompressedBufferSize,CompressedBuffer,CompressedBufferSize,FinalUncompressedSize)) = self.get_funcargs(event)
pid = event.get_pid()
tid = event.get_tid()
log("[*] <%d:%d> 0x%x: RtlDecompressBuffer(0x%x,0x%x,0x%x,0x%x,0x%x,0x%x): %d" % (pid,tid,ra,CompressionFormat,UncompressedBuffer,UncompressedBufferSize,CompressedBuffer,CompressedBufferSize,FinalUncompressedSize,retval))
# Get a Process object, and dereference the FinalUncompressedSize argument
p = event.get_process()
buffsize = p.read_uint(FinalUncompressedSize)
# C.4.4 save a copy of the decompressed data
filename_comp = "%s.memblk0x%x.comp" % (sys.argv[1],CompressedBuffer)
filename = "%s.memblk0x%x.decomp" % (sys.argv[1],UncompressedBuffer)
log("[-] Dumping %d bytes of decompressed memory at 0x%x to %s" % (buffsize,UncompressedBuffer,filename))
databuff = open(filename,"wb")
databuff.write(p.read(UncompressedBuffer,buffsize))
databuff.close()
# C.4.5 Create a JSON event log entry
self.eventlog.append({
"time": time.time(),
"name": "RtlDecompressBuffer",
"type": "Win32 API",
"pid": pid,
"tid": tid,
"addr": ra,
"args": {
"CompressionFormat": CompressionFormat,
"UncompressedBuffer": UncompressedBuffer,
"UncompressedBufferSize": UncompressedBufferSize,
"CompressedBuffer": CompressedBuffer,
"CompressedBufferSize": CompressedBufferSize,
"FinalUncompressedSize": FinalUncompressedSize
},
"ret": retval,
"info": {
"filename_comp": filename_comp,
"filename_decomp": filename
}
})
except:
traceback.print_exc()
raise
# C.5
# CreateProcess() hook(s)
#
def post_CreateProcess(self,event,retval,fUnicode):
try:
# C.5.1 Get the return address and arguments
(ra,(lpApplicationName,lpCommandLine,lpProcessAttributes,lpThreadAttributes,bInheritHandles,dwCreationFlags,lpEnvironment,lpCurrentDirectory,lpStartupInfo,lpProcessInformation)) = self.get_funcargs(event)
p = event.get_process()
t = event.get_thread()
pid = event.get_pid()
tid = event.get_tid()
# C.5.2 Dereference arguments
# Use the Process object to dereference the lpApplicationName and lpCommandLine arguments
# as either ASCII or WCHAR depending on the fUnicode argument
# (and hence whether we were called from post_CreateProcessA() or post_CreateProcessW() respectively
szApplicationName = p.peek_string(lpApplicationName,fUnicode)
szCommandLine = p.peek_string(lpCommandLine,fUnicode)
# If the lpProcessInformation argument is a valid pointer...
if (lpProcessInformation):
# ... dereference it to get the ProcessInformation structure
d = event.debug
ProcessInformation = self.guarded_read(d,t,lpProcessInformation,16)
# Extract the various fields from the ProcessInformation structure
hProcess = struct.unpack("<L",ProcessInformation[0:4])[0]
hThread = struct.unpack("<L",ProcessInformation[4:8])[0]
dwProcessId = struct.unpack("<L",ProcessInformation[8:12])[0]
dwThreadId = struct.unpack("<L",ProcessInformation[12:16])[0]
else:
log("[E] lpProcessInformation is null")
log("[*] <%d:%d> 0x%x: CreateProcess(\"%s\",\"%s\",0x%x): %d (0x%x, 0x%x, <%d:%d>)" % (pid,tid,ra,szApplicationName,szCommandLine,dwCreationFlags,retval,hProcess,hThread,dwProcessId,dwThreadId))
# C.5.3 Check if the process is being created in a suspended state (CREATE_SUSPENDED flag)...
if (dwCreationFlags & 0x4):
# ... hook the ResumeThread() API call
# so that we are notified when it is resumed
d = event.debug
stat = d.hook_function(pid,"ResumeThread",preCB = self.hook_createsuspendedresume,paramCount = 1)
self.createsuspended[(pid,hThread)] = dwProcessId
log("[-] CREATE_SUSPENDED. Hooking ResumeThread() (%d)" % stat)
# C.5.4 Keep track of processes that were created, so we know which
# process any WriteProcessMemory() calls are writing to
self.createdprocesses[hProcess] = {
"time": time.time(),
"ppid": pid,
"ptid": tid,
"paddr": ra,
"ApplicationName":szApplicationName,
"CommandLine": szCommandLine,
"CreationFlags": dwCreationFlags,
"hProcess": hProcess,
"hThread": hThread,
"ProcessId": dwProcessId,
"ThreadId": dwThreadId
}
# C.5.5 Create a JSON event log entry
self.eventlog.append({
"time": time.time(),
"name": "CreateProcess",
"type": "Win32 API",
"pid": pid,
"tid": tid,
"addr": ra,
"args": {
"ApplicationName":szApplicationName,
"CommandLine": szCommandLine,
"CreationFlags": dwCreationFlags,
"hProcess": hProcess,
"hThread": hThread,
"ProcessId": dwProcessId,
"ThreadId": dwThreadId
},
"info": {
"fUnicode":fUnicode
},
"ret": retval
})
except:
traceback.print_exc()
raise
# C.5.6 post_CreateProcessA() and post_CreateProcessW()
# Actual hook call-back function called by WinAppDbg
# To save duplicating code between this and post_CreateProcessW()
# both of them call post_CreateProcess() with a parameter, fUnicode,
# which specifies whether the strings are ASCII (CreateProcessA())
# or WCHAR (CreateProcessW())
def post_CreateProcessA(self,event,retval):
self.post_CreateProcess(event,retval,False)
def post_CreateProcessW(self,event,retval):
self.post_CreateProcess(event,retval,True)
# hook_createsuspendedresume() is a call-back function called when
# ResumeThread() is call by a process which has created a suspended
# process
def hook_createsuspendedresume(self,event,*args):
# C.5.7 Get the return address and arguments
(ra,(hThread,)) = self.get_funcargs(event)
pid = event.get_pid()
tid = event.get_tid()
log("[*] <%d:%d> 0x%x: ResumeThread(0x%x)" % (pid,tid,ra,hThread))
# C.5.8 Find the process id of the resumed process
if ((pid,hThread) in self.createsuspended):
pidresumed = self.createsuspended[(pid,hThread)]
log("[-] New suspended process (pid %d) resumed" % pidresumed)
# C.6
# WriteProcessMemory() hook(s)
#
def post_WriteProcessMemory(self,event,retval):
# C.6.1 Get the return address and arguments
try:
(ra,(hProcess,lpBaseAddress,lpBuffer,nSize,lpNumberOfBytesWritten)) = self.get_funcargs(event)
pid = event.get_pid()
tid = event.get_tid()
log("[*] <%d:%d> 0x%x: WriteProcessMemory(0x%x,0x%x,0x%x,0x%x,0x%x): %d" % (pid,tid,ra,hProcess,lpBaseAddress,lpBuffer,nSize,lpNumberOfBytesWritten,retval))
d = event.debug
t = event.get_thread()
# C.6.2 Dereference lpNumberOfBytesWritten to get the number of bytes written to the target process'
# address space
if (lpNumberOfBytesWritten):
NumberOfBytesWritten = struct.unpack("<L",self.guarded_read(d,t,lpNumberOfBytesWritten,4))[0]
else:
NumberOfBytesWritten = None
# C.6.3 Get process information that was saved by CreateProcess() hook
if (hProcess in self.createdprocesses):
ProcessId = self.createdprocesses[hProcess]["ProcessId"]
ApplicationName = self.createdprocesses[hProcess]["ApplicationName"]
CommandLine = self.createdprocesses[hProcess]["CommandLine"]
else:
log("[W] hProcess not in createdprocesses[]")
ProcessId = None
ApplicationName = None
CommandLine = None
d = event.debug
t = event.get_thread()
# C.6.4 Save a copy of the written memory
pid = event.get_pid()
tid = event.get_tid()
filename = "%s.memblk0x%x-%d.wpm" % (sys.argv[1],lpBaseAddress,ProcessId)
log("[-] Dumping %d bytes of memory at %d:0x%x written to %d:0x%x to %s" % (nSize,pid,lpBuffer,ProcessId,lpBaseAddress,filename))
databuff = open(filename,"wb")
databuff.write(self.guarded_read(d,t,lpBuffer,nSize))
databuff.close()
# C.6.5 Create a JSON event log entry
self.eventlog.append({
"time": time.time(),
"name": "WriteProcessMemory",
"type": "Win32 API",
"pid": pid,
"tid": tid,
"addr": ra,
"args": {
"hProcess": hProcess,
"lpBaseAddress": lpBaseAddress,
"lpBuffer": lpBuffer,
"nSize": nSize,
"lpNumberOfBytesWritten": lpNumberOfBytesWritten,
"NumberOfBytesWritten": NumberOfBytesWritten
},
"ret": retval,
"info": {
"filename": filename,
"targetprocesspid": ProcessId,
"targetprocessname": ApplicationName,
"targetprocesscmdline": CommandLine
}
})
except:
traceback.print_exc()
raise
# C.7
# IsDebuggerPresent() hook(s)
# (mainly added so that AutoIt compiled scripts would run, but also useful
# as an anti-anti-malware technique)
#
def post_IsDebuggerPresent(self,event,retval):
# C.7.1 Get the return address and arguments
(ra,noargs) = self.get_funcargs(event)
pid = event.get_pid()
tid = event.get_tid()
log("[*] <%d:%d> 0x%x: IsDebuggerPresent(): 0x%x" % (pid,tid,ra,retval))
log("[-] Returning 0")
# C.7.2 Changed the 'eax' register (return value) to '0' (no debugger present)
# just before we continue running the calling thread
t = event.get_thread()
t.set_register("Eax",0x0)
# C.7.3 Create a JSON event log entry
self.eventlog.append({
"time": time.time(),
"name": "IsDebuggerPresent",
"type": "Win32 API",
"pid": pid,
"tid": tid,
"addr": ra,
"args": {},
"ret": retval,
"info": {}
})
# C.8
# InternetOpen() hook(s)
#
def post_InternetOpen(self,event,retval,fUnicode):
# C.8.1 Get the return address and arguments
(ra,(lpszAgent,dwAccessType,lpszProxyName,lpszProxyBypass,dwFlags)) = self.get_funcargs(event)
pid = event.get_pid()
tid = event.get_tid()
# C.8.2 Dereference arguments
p = event.get_process()
szAgent = p.peek_string(lpszAgent,fUnicode)
szProxyName = p.peek_string(lpszProxyName,fUnicode)
szProxyBypass = p.peek_string(lpszProxyBypass,fUnicode)
log("[*] <%d:%d> 0x%x: InternetOpen(\"%s\",0x%x,\"%s\",\"%s\",0x%x) = 0x%x" % (pid,tid,ra,szAgent,dwAccessType,szProxyName,szProxyBypass,dwFlags,retval))
# C.8.3 Create a JSON event log entry
self.eventlog.append({
"time": time.time(),
"name": "InternetOpen",
"type": "Win32 API",
"pid": pid,
"tid": tid,
"addr": ra,
"args": {},
"ret": retval,
"info": {}
})
def post_InternetOpenA(self,event,retval):
self.post_InternetOpen(event,retval,False)
def post_InternetOpenW(self,event,retval):
self.post_InternetOpen(event,retval,True)
def pre_EncryptMessage(self,event,*args):
# C.?.1 Get the return address and arguments
try:
(ra,phContext,fQOP,pMessage,MessageSeqNo) = (args[0],args[1],args[2],args[3],args[4])
pid = event.get_pid()
tid = event.get_tid()
# Right -- this is going to get annoying
# pMessage is a pointer to a SecBufferDesc structure
# which describes an array of SecBuffer structures
p = event.get_process()
l = p.get_label_at_address(ra)
# really ought to use a ctypes struct for this!
ulVersion = p.peek_uint(pMessage)
cBuffers = p.peek_uint(pMessage + 4)
pBuffers = p.peek_uint(pMessage + 8)
log("[*] <%d:%d> %s 0x%x: EncryptMessage(...)" % (pid,tid,l,ra))
log("[D] ulVersion: %d" % ulVersion)
log("[D] cBuffers: %d" % cBuffers)
log("[D] pBuffers: 0x%x" % pBuffers)
# dump buffer list
for i in range(0,cBuffers):
cbBuffer = p.peek_uint(pBuffers + (i * 12) + 0)
BufferType = p.peek_uint(pBuffers + (i * 12) + 4)
pvBuffer = p.peek_uint(pBuffers + (i * 12) + 8)
if (BufferType == 1): # SECBUFFER_DATA
# we have data to save
filename = sys.argv[1] + ".encmsg0x%08x-%d" % (pvBuffer,pid)
f = open(filename,"ab")
f.write(p.peek(pvBuffer,cbBuffer))
f.close()
log("[D]")
log("[D] cbBuffer: 0x%x (%d)" % (cbBuffer,cbBuffer))
log("[D] BufferType: 0x%x" % BufferType)
log("[D] pvBuffer: 0x%x" % pvBuffer)
except:
traceback.print_exc()
raise
def post_DecryptMessage(self,event,retval):
# C.?.1 Get the return address and arguments
try:
(ra,(phContext,pMessage,MessageSeqNo,pfQOP)) = self.get_funcargs(event)
pid = event.get_pid()
tid = event.get_tid()
# Right -- this is going to get annoying
# pMessage is a pointer to a SecBufferDesc structure
# which describes an array of SecBuffer structures
p = event.get_process()
# really ought to use a ctypes struct for this!
ulVersion = p.peek_uint(pMessage)
cBuffers = p.peek_uint(pMessage + 4)
pBuffers = p.peek_uint(pMessage + 8)
log("[*] <%d:%d> 0x%x: DecryptMessage(...)" % (pid,tid,ra))
log("[D] ulVersion: %d" % ulVersion)
log("[D] cBuffers: %d" % cBuffers)
log("[D] pBuffers: 0x%x" % pBuffers)
# dump buffer list
for i in range(0,cBuffers):
cbBuffer = p.peek_uint(pBuffers + (i * 12) + 0)
BufferType = p.peek_uint(pBuffers + (i * 12) + 4)
pvBuffer = p.peek_uint(pBuffers + (i * 12) + 8)
if (BufferType == 1): # SECBUFFER_DATA
# we have data to save
filename = sys.argv[1] + ".decmsg0x%08x-%d" % (pvBuffer,pid)
f = open(filename,"ab")
f.write(p.peek(pvBuffer,cbBuffer))
f.close()
log("[D]")
log("[D] cbBuffer: 0x%x (%d)" % (cbBuffer,cbBuffer))
log("[D] BufferType: 0x%x" % BufferType)
log("[D] pvBuffer: 0x%x" % pvBuffer)
except:
traceback.print_exc()
raise
###
# D. winappdbg debug event handlers
###
### D.1
# create_process
#
# winappdbg defined callback function to handle process creation events
###
def create_process(self,event):
p = event.get_process()
pid = event.get_pid()
tid = event.get_tid()
log("[*] <%d:%d> Create process event for pid %d (%s)" % (pid,tid,p.get_pid(),p.get_image_name()))
log("[-] command line: %s" % p.get_command_line())
#log("[D] Create process event for pid %d (%d)" % (pid,tid))
self.eventlog.append({
"time": time.time(),
"name": event.get_event_name(),
"type": "WinAppDbg Event",
"pid": pid,
"tid": tid,
"info": {
"pid": p.get_pid(),
"module_base": event.get_module_base(),
"filename": event.get_filename(),
"cmdline": p.get_command_line()
},
})
### D.2
# exit_process
#
# winappdbg defined callback function to handle process exit events
###
def exit_process(self,event):
pid = event.get_pid()
tid = event.get_tid()
log("[*] <%d:%d> Exit process event for %s: 0x%x" % (pid,tid,event.get_filename(),event.get_exit_code()))
self.eventlog.append({
"time": time.time(),
"name": event.get_event_name(),
"type": "WinAppDbg Event",
"pid": pid,
"tid": tid,
"info": {
"module_base": event.get_module_base(),
"filename": event.get_filename(),
"exitcode": event.get_exit_code()
},
})
### D.3
# create_thread
#
# winappdbg defined callback function to handle thread creation events
###
def create_thread(self,event):
pid = event.get_pid()
tid = event.get_tid()
t = event.get_thread()
name = t.get_name()
log("[*] <%d:%d> Create thread event \"%s\" @ 0x%x" % (pid,tid,name,event.get_start_address()))
self.eventlog.append({
"time": time.time(),
"name": event.get_event_name(),
"type": "WinAppDbg Event",
"pid": pid,
"tid": tid,
"info": {
"startaddress": event.get_start_address(),
"threadname": name
},
})
### D.4
# exit_thread
#
# winappdbg defined callback function to handle thread exit events
###
def exit_thread(self,event):
pid = event.get_pid()
tid = event.get_tid()
t = event.get_thread()
name = t.get_name()
log("[*] <%d:%d> Exit thread event \"%s\"" % (pid,tid,name,))
self.eventlog.append({
"time": time.time(),
"name": event.get_event_name(),
"type": "WinAppDbg Event",
"pid": pid,
"tid": tid,
"info": {
"threadname": name
},
})
### D.5
# load_dll
#
# winappdbg defined callback function to handle DLL load events
###
def load_dll(self,event):
pid = event.get_pid()
tid = event.get_tid()
log("[*] <%d:%d> Load DLL event: %s" % (pid,tid,event.get_filename()))
self.eventlog.append({
"time": time.time(),
"name": event.get_event_name(),
"type": "WinAppDbg Event",
"pid": pid,
"tid": tid,
"info": {
"module_base": event.get_module_base(),
"filename": event.get_filename(),
},
})
### D.6
# event
#
# winappdbg defined callback function to handle any remaining events
###
def event(self,event):
pid = event.get_pid()
tid = event.get_tid()