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funcap.py
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'''
Created on Nov 21, 2012
@author: [email protected]
@contributors: Bartol0 @ github
@version: 0.91
FunCap. A script to capture function calls during a debug session in IDA.
It is created to help quickly importing some runtime data into static IDA database to boost static analysis.
Was meant to be multi-modular but seems IDA does not like scripts broken in several files/modules.
So we got one fat script file atm.
'''
# 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; either version 2 of the License, or (at your option) any later
# version.
#
# 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
#
## BUGS:
# - need to cancel "Analyze Area" if it takes too long - code analysis problem in IDA ?
#
## TODO LIST:
# - better call and ret association: build a call tree for each thread instead of current stack pointer-based hashing (this turns out not reliable).
# - function call capture using tracing (thinking here about PIN as only this one is fast enough).
# We will probably have to calculate the destination jump address instead of using single stepping - it will be much more stable
# - instead of simple arg frame size calculation (get_num_args_stack()) + argument primitive type guessing (string, int),
# we need to read in function prototypes guessed by IDA (or even HexRays decompiler plugin...) and match arguments to them
# maybe it could be possible by getting some info from underlying debugger symbols via WinDbg/GDB, IDA pro static arg list analysis
# - some database interface for collected data + UI plugin in IDA - so that right click on a function call in IDA will show
# the table with links to different captures for that particular call. This would be really cool.
# - amd64 stack-based arguments are not always well captured
# IDA imports
import sys
from idaapi import *
from idautils import *
from idc import *
# utility functions
def format_name(ea):
name = GetFunctionName(ea)
if name == "" or name == None:
name = "0x%x" % ea
return name
def format_offset(ea):
offset = GetFuncOffset(ea)
if offset == "" or offset == None:
offset = "0x%x" % ea
return offset
def get_arch():
'''
Get the target architecture.
Supported archs: x86 32-bit, x86 64-bit, ARM 32-bit
'''
(arch, bits) = (None, None)
for x in idaapi.dbg_get_registers():
name = x[0]
if name == 'RAX':
arch = 'amd64'
bits = 64
break
elif name == 'EAX':
arch = 'x86'
bits = 32
break
elif name == 'R0':
arch = 'arm'
bits = 32
break
return (arch, bits)
class FunCapHook(DBG_Hooks):
'''
Main class to implementing DBG_Hooks
'''
## CONSTANTS
# minimum length requirement to be ascii
STRING_EXPLORATION_MIN_LENGTH = 4
# length of discovered strings outputted to file and console
STRING_LENGTH = 164
# length of the same strings inserted in IDA code
STRING_LENGTH_IN_COMMENTS = 82
# length of single-line hexdumps in hexdump mode outputted to file and console
HEXMODE_LENGTH = 164
# length of the same hexdumps inserted in IDA code
HEXMODE_LENGTH_IN_COMMENTS = 82
# visited functions will be tagged as follows
FUNC_COLOR = 0xF7CBEA
# visited items (except call instructions) will be tagged as follows
ITEM_COLOR = 0x70E01B
# calls will be tagged as follows
CALL_COLOR = 0x99CCCC
# maximum comment lines inserted after/before call instructions
CMT_MAX = 5
def __init__(self, **kwargs):
'''
@param outfile: log file where the output dump will be written (default: %USERPROFILE%\funcap.txt)
@param delete_breakpoints: delete a breakpoint after first pass ? (default: yes)
@param hexdump: include hexdump instead of ascii in outfile and IDA comments ? (default: no)
@param comments: add IDA comments ? (default: yes)
@param resume: resume program after hitting a breakpoint ? (default: yes)
@param depth: current stack depth capture for non-function hits (default: 0)
@param colors: mark the passage with colors ? (default: yes)
@param output_console: print everything to the console ? (default: yes)
@param overwrite_existing: overwrite existing capture comment in IDA when the same function is called ? (default: no)
@param recursive: when breaking on a call - are we recursively hooking all call instructions in the new function ? (default: no)
@param code_discovery: enable discovery of a dynamically created code - for obfuscators and stuff like that (default: no)
@param no_dll: disable API calls capturing (default: no)
@param strings_file: file containing strings dump on captured function arguments (default: %USERPROFILE%\funcap_strings.txt)
@param multiple_dereferences: dereference each pointer resursively ? (default: 3 levels, 0 - off)
'''
self.outfile = kwargs.get('outfile', os.path.expanduser('~') + "/funcap.txt")
self.delete_breakpoints = kwargs.get('delete_breakpoints', True)
self.hexdump = kwargs.get('hexdump', False)
self.comments = kwargs.get('comments', True)
self.resume = kwargs.get('resume', True)
self.depth = kwargs.get('depth', 0)
self.colors = kwargs.get('colors', True)
self.output_console = kwargs.get('output_console', True)
self.overwrite_existing = kwargs.get('overwrite_existing', False)
self.recursive = kwargs.get('recursive', False)
self.code_discovery = kwargs.get('code_discovery', False) # for obfuscators
self.no_dll = kwargs.get('no_dll', False)
self.strings_file = kwargs.get('strings', os.path.expanduser('~') + "/funcap_strings.txt")
self.multiple_dereferences = kwargs.get('multiple_dereferences', 3)
self.visited = [] # functions visited already
self.saved_contexts = {} # saved stack contexts - to re-dereference arguments when the function exits
self.function_calls = {} # recorded function calls - used for several purposes
self.stop_points = [] # brekpoints where FunCap will pause the process to let user start the analysis
self.calls_graph = {} # graph nodes prepared for call graphs
self.hooked = [] # functions that were already hooked
self.stub_steps = 0
self.stub_name = None
self.current_caller = None # for single step - before-call context
self.delayed_caller = None # needed in case where single step lands on breakpoint (brekpoint fires first - which is bad...)
DBG_Hooks.__init__(self)
self.out = None
self.strings_out = None
###
# This a is public interface
# Switches are to be set manually - too lazy to implement setters and getters
# I started to implement GUI as well but it did not work as expected so it won't be implemented...
###
def on(self):
'''
Turn the script on
'''
if self.outfile:
self.out = open(self.outfile, 'w')
if self.strings_file:
self.strings_out = open(self.strings_file, 'w')
self.hook()
print "FunCap is ON"
def off(self):
'''
Turn the script off
'''
if self.out != None:
self.out.close()
self.unhook()
print "FunCap is OFF"
def addFuncStart(self):
'''
Add breakpoints on all function starts
'''
for f in list(Functions()):
AddBpt(f)
def addFuncRet(self):
'''
Add breakpoints on all return from subroutine instructions
'''
for seg_ea in Segments():
# For each of the defined elements
for head in Heads(seg_ea, SegEnd(seg_ea)):
# If it's an instruction
if isCode(GetFlags(head)):
if self.is_ret(head):
AddBpt(head)
def addCallee(self):
'''
Add breakpoints on both function starts and return instructions
'''
self.addFuncStart()
self.addFuncRet()
def hookFunc(self, jump = False, func = ""):
'''
Add breakpoints on call instructions within a function
@param jump: if True, jump instructions will also be hooked in addition to calls - used in code discovery mode
@param func: this should be a function name. If null, the function that UI cursor points to will be processed
'''
if func:
ea = LocByName(func)
else:
ea = ScreenEA()
func = GetFunctionName(ea)
self.output("hooking function: %s()" % func)
f = get_func(ea)
start_ea = f.startEA
end_ea = f.endEA
if jump:
self.add_call_and_jump_bp(start_ea, end_ea)
else:
self.add_call_bp(start_ea, end_ea)
self.hooked.append(func)
def hookSeg(self, seg = "", jump = False):
'''
Add breakpoints on call instructions within a given segment
@param jump: if True, jump instructions will also be hooked in addition to calls - used in code discovery mode
@param seg: this should be a segment name. If null, the segment that UI cursor points to will be processed
'''
if seg:
ea = None
for s in Segments():
if seg == SegName(s):
ea = s
break
if ea == None:
self.output("WARNING: cannot hook segment %s" % seg)
return
else:
ea = ScreenEA()
seg = SegName(ea)
self.output("hooking segment: %s" % seg)
start_ea = SegStart(ea)
end_ea = SegEnd(ea)
if jump:
self.add_call_and_jump_bp(start_ea, end_ea)
else:
self.add_call_bp(start_ea, end_ea)
def addCJ(self, func = ""):
'''
Hook all call and jump instructions
@param func: name of the function to hook
'''
self.hookFunc(jump = True, func = func)
def delAll(self):
'''
Delete all breakpoints
'''
for bp in range(GetBptQty(), 0, -1):
DelBpt(GetBptEA(bp))
def graph(self, exact_offsets = False):
'''
Draw the graph
@param exact_offsets: if enabled each function call with offset(e.g. function+0x12) will be treated as graph node
if disabled, only function name will be presented as node (more regular graph but less precise information)
'''
CallGraph("FunCap: function calls", self.calls_graph, exact_offsets).Show()
def addStop(self, ea):
'''
Add a stop point - the script will pause the process when this is reached
@param ea: address of the new stop point to add
'''
self.stop_points.append(ea)
AddBpt(ea)
###
# END of public interface
###
def add_call_bp(self, start_ea, end_ea):
'''
Add breakpoints on every subrountine call instruction within the given scope (start_ea, end_ea)
@param start_ea:
@param end_ea:
'''
for head in Heads(start_ea, end_ea):
# If it's an instruction
if isCode(GetFlags(head)):
if self.is_call(head):
AddBpt(head)
def add_call_and_jump_bp(self, start_ea, end_ea):
'''
Add breakpoints on every subrountine call instruction and jump instruction within the given scope (start_ea, end_ea)
@param start_ea:
@param end_ea:
'''
for head in Heads(start_ea, end_ea):
# If it's an instruction
if isCode(GetFlags(head)):
if (self.is_call(head) or self.is_jump(head)):
AddBpt(head)
def get_num_args_stack(self, addr):
'''
Get the size of arguments frame
@param addr: address belonging to a function
'''
argFrameSize = GetStrucSize(GetFrame(addr)) - GetFrameSize(addr) + GetFrameArgsSize(addr)
return argFrameSize / (self.bits/8)
def get_caller(self):
return self.prev_ins(self.return_address())
def format_caller(self, ret):
return format_offset(ret) + " (0x%x)" % ret
def getRegValueFromCtx(self, name, context):
'''
Extract the value of a single register from the saved context
@param name: name of the register to extract
@param context: saved execution context
'''
for reg in context:
if reg['name'] == name:
return reg['value']
def add_comments(self, ea, lines, every = False):
'''
Insert lines (posterior and anterior lines which are referred to as "comments" in this code) into IDA assembly listing
@param ea: address where to insert the comments
@param lines: array of strings to be inserted as multiple lines using ExtLinA()
@param every: if set to True, the maximum number of lines per address (self.CMT_MAX) will not be respected
'''
idx = 0
for line in lines:
# workaround with Eval() - ExtLinA() doesn't work well in idapython
line_sanitized = line.replace('"', '\\"')
ret = idc.Eval('ExtLinA(%d, %d, "%s");' % (ea, idx, line_sanitized))
if ret:
self.output("idc.Eval() returned an error: %s" % ret)
idx += 1
if every == False and idx > self.CMT_MAX: break
def format_normal(self, regs):
'''
Returns two lists of formatted values and derefs of registers, one for console/file dump, and another for IDA comments (tha latter is less complete)
Used for everything besides calling and returning from function.
@param regs: dictionary returned by get_context()
'''
full_ctx = []
cmt_ctx = []
maxdepth = self.multiple_dereferences
if self.bits == 32:
format_string = "%3s: 0x%08x"
format_string_append = " -> 0x%08x"
getword = DbgDword
else:
format_string = "%3s: 0x%016x"
format_string_append = " -> 0x%016x"
getword = DbgQword
memval = None
next_memval = None
prev_memval = None
valchain_full = ""
valchain_cmt = ""
for reg in regs:
valchain_full = format_string % (reg['name'], reg['value'])
valchain_cmt = format_string % (reg['name'], reg['value'])
prev_memval = reg['value']
memval=getword(reg['value'])
next_memval = getword(memval)
if (self.multiple_dereferences):
while (next_memval): #memval is a proper pointer
valchain_full += format_string_append % memval
valchain_cmt += format_string_append % memval
if (prev_memval == memval):#points at itself
break
if (maxdepth == 0):
break
maxdepth-=1
prev_memval = memval
memval = next_memval
next_memval = getword(memval)
function_name=GetFuncOffset(prev_memval)#no more dereferencing. is this a function ?
if (function_name):
valchain_full += " (%s)" % function_name
valchain_cmt += " (%s)" % function_name
else: #no, dump data
if (self.hexdump):
valchain_full_left = (self.HEXMODE_LENGTH - len(valchain_full) - 1) / 4
valchain_cmt_left = (self.HEXMODE_LENGTH_IN_COMMENTS - len(valchain_cmt) - 1) / 4
format_string_dump = " (%s)"
else:
valchain_full_left = self.STRING_LENGTH - len(valchain_full)
valchain_cmt_left = self.STRING_LENGTH_IN_COMMENTS - len(valchain_cmt)
format_string_dump = " (\"%s\")"
if (valchain_full_left <4): valchain_full_left = 4 #allways dump at least 4 bytes
if (valchain_cmt_left <4): valchain_cmt_left = 4 #allways dump at least 4 bytes
valchain_full += format_string_dump % self.smart_format(self.dereference(prev_memval,2 * valchain_full_left), valchain_full_left)
valchain_cmt += format_string_dump % self.smart_format_cmt(self.dereference(prev_memval,2 * valchain_cmt_left),valchain_cmt_left)
full_ctx.append(valchain_full)
cmt_ctx.append(valchain_cmt)
return (full_ctx, cmt_ctx)
def format_call(self, regs):
'''
Returns two lists of formatted values and derefs of registers, one for console/file dump, and another for IDA comments
Used when calling a function.
@param regs: dictionary returned by get_context()
'''
full_ctx = []
cmt_ctx = []
maxdepth = self.multiple_dereferences
if self.bits == 32:
format_string_full = "%3s: 0x%08x"
format_string_cmt = " %3s: 0x%08x"
format_string_append = " -> 0x%08x"
getword = DbgDword
else:
format_string_full = "%3s: 0x%016x"
format_string_cmt = " %3s: 0x%016x"
format_string_append = " -> 0x%016x"
getword = DbgQword
memval = None
next_memval = None
prev_memval = None
valchain_full = ""
valchain_cmt = ""
for reg in regs:
valchain_full = format_string_full % (reg['name'], reg['value'])
valchain_cmt = format_string_cmt % (reg['name'], reg['value'])
prev_memval = reg['value']
memval=getword(reg['value'])
next_memval = getword(memval)
if (self.multiple_dereferences):
while (next_memval): #memval is a proper pointer
valchain_full += format_string_append % memval
valchain_cmt += format_string_append % memval
if (prev_memval == memval):#points at itself
break
if (maxdepth == 0):
break
maxdepth-=1
prev_memval = memval
memval = next_memval
next_memval = getword(memval)
function_name=GetFuncOffset(prev_memval)#no more dereferencing. is this a function ?
if (function_name):
valchain_full += " (%s)" % function_name
valchain_cmt += " (%s)" % function_name
else: #no, dump data
if (self.hexdump):
valchain_full_left = (self.HEXMODE_LENGTH - len(valchain_full) - 1) / 4
valchain_cmt_left = (self.HEXMODE_LENGTH_IN_COMMENTS - len(valchain_cmt) - 1) / 4
format_string_dump = " (%s)"
else:
valchain_full_left = self.STRING_LENGTH - len(valchain_full)
valchain_cmt_left = self.STRING_LENGTH_IN_COMMENTS - len(valchain_cmt)
format_string_dump = " (\"%s\")"
if (valchain_full_left <4): valchain_full_left = 4 #allways dump at least 4 bytes
if (valchain_cmt_left <4): valchain_cmt_left = 4 #allways dump at least 4 bytes
valchain_full += format_string_dump % self.smart_format(self.dereference(prev_memval,2 * valchain_full_left), valchain_full_left)
valchain_cmt += format_string_dump % self.smart_format_cmt(self.dereference(prev_memval,2 * valchain_cmt_left),valchain_cmt_left)
full_ctx.append(valchain_full)
if any(regex.match(reg['name']) for regex in self.CMT_CALL_CTX):
cmt_ctx.append(valchain_cmt)
return (full_ctx, cmt_ctx)
def format_return(self, regs, saved_regs):
'''
Returns two lists of formatted values and derefs of registers, one for console/file dump, and another for IDA comments
Used when returning from function.
@param regs: dictionary returned by get_context()
@param saved_regs: dictionary in the format returned by get_context()
'''
full_ctx = []
cmt_ctx = []
maxdepth = self.multiple_dereferences
if self.bits == 32:
format_string_append = " -> 0x%08x"
format_string_full = "%3s: 0x%08x"
format_string_cmt = " %3s: 0x%08x"
getword = DbgDword
else:
format_string_full = "%3s: 0x%016x"
format_string_cmt = " %3s: 0x%016x"
format_string_append = " -> 0x%016x"
getword = DbgQword
memval = None
next_memval = None
prev_memval = None
valchain_full = ""
valchain_cmt = ""
for reg in regs:
valchain_full = format_string_full % (reg['name'], reg['value'])
valchain_cmt = format_string_cmt % (reg['name'], reg['value'])
prev_memval = reg['value']
memval=getword(reg['value'])
next_memval = getword(memval)
if (self.multiple_dereferences):
while (next_memval): #memval is a proper pointer
valchain_full += format_string_append % memval
valchain_cmt += format_string_append % memval
if (prev_memval == memval):#points at itself
break
if (maxdepth == 0):
break
maxdepth-=1
prev_memval = memval
memval = next_memval
next_memval = getword(memval)
function_name=GetFuncOffset(prev_memval)#no more dereferencing. is this a function ?
if (function_name):
valchain_full += " (%s)" % function_name
valchain_cmt += " (%s)" % function_name
else: #no, dump data
if (self.hexdump):
valchain_full_left = (self.HEXMODE_LENGTH - len(valchain_full) - 1) / 4
valchain_cmt_left = (self.HEXMODE_LENGTH_IN_COMMENTS - len(valchain_cmt) - 1) / 4
format_string_dump = " (%s)"
else:
valchain_full_left = self.STRING_LENGTH - len(valchain_full)
valchain_cmt_left = self.STRING_LENGTH_IN_COMMENTS - len(valchain_cmt)
format_string_dump = " (\"%s\")"
if (valchain_full_left <4): valchain_full_left = 4 #allways dump at least 4 bytes
if (valchain_cmt_left <4): valchain_cmt_left = 4 #allways dump at least 4 bytes
valchain_full += format_string_dump % self.smart_format(self.dereference(prev_memval,2 * valchain_full_left), valchain_full_left)
valchain_cmt += format_string_dump % self.smart_format_cmt(self.dereference(prev_memval,2 * valchain_cmt_left),valchain_cmt_left)
full_ctx.append(valchain_full)
if any(regex.match(reg['name']) for regex in self.CMT_RET_CTX):
cmt_ctx.append(valchain_cmt)
if saved_regs:
for reg in saved_regs:
if any(regex.match(reg['name']) for regex in self.CMT_RET_SAVED_CTX):
valchain_full = format_string_full % (reg['name'], reg['value'])
valchain_cmt = format_string_cmt % (reg['name'], reg['value'])
prev_memval = reg['value']
memval=getword(reg['value'])
next_memval = getword(memval)
if (self.multiple_dereferences):
while (next_memval): #memval is a proper pointer
valchain_full += format_string_append % memval
valchain_cmt += format_string_append % memval
if (prev_memval == memval):#points at itself
break
if (maxdepth == 0):
break
maxdepth-=1
prev_memval = memval
memval = next_memval
next_memval = getword(memval)
function_name=GetFuncOffset(prev_memval)#no more dereferencing. is this a function ?
if (function_name):
valchain_full += " (%s)" % function_name
valchain_cmt += " (%s)" % function_name
else: #no, dump data
if (self.hexdump):
valchain_full_left = (self.HEXMODE_LENGTH - len(valchain_full) - 1) / 4
valchain_cmt_left = (self.HEXMODE_LENGTH_IN_COMMENTS - len(valchain_cmt) - 1) / 4
format_string_dump = " (%s)"
else:
valchain_full_left = self.STRING_LENGTH - len(valchain_full)
valchain_cmt_left = self.STRING_LENGTH_IN_COMMENTS - len(valchain_cmt)
format_string_dump = " (\"%s\")"
if (valchain_full_left <4): valchain_full_left = 4 #allways dump at least 4 bytes
if (valchain_cmt_left <4): valchain_cmt_left = 4 #allways dump at least 4 bytes
valchain_full += format_string_dump % self.smart_format(self.dereference(prev_memval,2 * valchain_full_left), valchain_full_left)
valchain_cmt += format_string_dump % self.smart_format_cmt(self.dereference(prev_memval,2 * valchain_cmt_left),valchain_cmt_left)
full_ctx.append(valchain_full)
cmt_ctx.append(valchain_cmt)
return (full_ctx, cmt_ctx)
def output(self, line):
'''
Standard "print" function used across the whole script
@param line: line to print
'''
if self.outfile:
self.out.write(line + "\n")
if self.output_console:
print line
if self.outfile:
self.out.flush()
def output_lines(self, lines):
'''
This prints a list, line by line
@param lines: lines to print
'''
for line in lines:
if self.outfile:
self.out.write(line + "\n")
if self.output_console:
print line
if self.outfile:
self.out.flush()
# the following few functions are adopted from PaiMei by Pedram Amini
# they are here to format and present data in a nice way
def get_ascii_string (self, data):
'''
Retrieve the ASCII string, if any, from data. Ensure that the string is valid by checking against the minimum
length requirement defined in self.STRING_EXPLORATION_MIN_LENGTH.
@type data: Raw
@param data: Data to explore for printable ascii string
@rtype: String
@return: False on failure, ascii string on discovered string.
'''
discovered = ""
for char in data:
# if we've hit a non printable char, break
if ord(char) < 32 or ord(char) > 126:
break
discovered += char
if len(discovered) < self.STRING_EXPLORATION_MIN_LENGTH:
return False
return discovered
def get_printable_string (self, data, print_dots=True):
'''
description
@type data: Raw
@param data: Data to explore for printable ascii string
@type print_dots: Bool
@param print_dots: (Optional, def:True) Controls suppression of dot in place of non-printable
@rtype: String
@return: False on failure, discovered printable chars in string otherwise.
'''
discovered = ""
for char in data:
if ord(char) >= 32 and ord(char) <= 126:
discovered += char
elif print_dots:
discovered += "."
return discovered
def get_unicode_string (self, data):
'''
description
@type data: Raw
@param data: Data to explore for printable unicode string
@rtype: String
@return: False on failure, ascii-converted unicode string on discovered string.
'''
discovered = ""
every_other = True
for char in data:
if every_other:
# if we've hit a non printable char, break
if ord(char) < 32 or ord(char) > 126:
break
discovered += char
every_other = not every_other
if len(discovered) < self.STRING_EXPLORATION_MIN_LENGTH:
return False
return discovered
def hex_dump(self, data):
'''
Utility function that converts data into one-line hex dump format.
@type data: Raw Bytes
@param data: Raw bytes to view in hex dump
@rtype: String
@return: Hex dump of data.
'''
dump = ""
for byte in data:
dump += "%02x " % ord(byte)
for byte in data:
if ord(byte) >= 32 and ord(byte) <= 126:
dump += byte
else:
dump += "."
return dump
def dereference(self, address, size):
return GetManyBytes(address, size, use_dbg=True)
def smart_format(self, raw_data, maxlen, print_dots=True):
'''
"Intelligently" discover data behind an address. The address is dereferenced and explored in search of an ASCII
or Unicode string. In the absense of a string the printable characters are returned with non-printables
represented as dots (.). The location of the discovered data is returned as well as either "heap", "stack" or
the name of the module it lies in (global data).
@param raw_data: Binary data to format
@type print_dots: Bool
@param print_dots: (Optional, def:True) Controls suppression of dot in place of non-printable
@rtype: String
@return: String of data discovered behind dereference.
'''
if not raw_data:
return 'N/A'
try_unicode = raw_data[:maxlen * 2]
try_ascii = raw_data[:maxlen]
data = raw_data[:maxlen]
data_string = self.get_ascii_string(try_ascii)
if not data_string:
data_string = self.get_unicode_string(try_unicode)
if not data_string and self.hexdump:
data_string = self.hex_dump(data)
if not data_string:
data_string = self.get_printable_string(data, print_dots)
# shouldn't have been here but the idea of string dumping came out to me later on
# TODO: re-implement. We could also take much longer strings
if self.strings_file:
self.strings_out.write(self.get_printable_string(raw_data, False) + "\n")
self.strings_out.flush()
return data_string
def smart_format_cmt(self, raw_data, maxlen, print_dots=True):
'''
Same as smart_format() but for IDA comments
'''
if not raw_data:
return 'N/A'
try_unicode = raw_data[:maxlen * 2]
try_ascii = raw_data[:maxlen]
data = raw_data[:maxlen]
data_string = self.get_ascii_string(try_ascii)
if not data_string:
data_string = self.get_unicode_string(try_unicode)
if not data_string and self.hexdump:
data_string = self.hex_dump(data)
if not data_string:
data_string = self.get_printable_string(data, print_dots)
return repr(data_string).strip("'")
def next_ins(self, ea):
'''
Return next instruction to ea
'''
end = idaapi.cvar.inf.maxEA
return idaapi.next_head(ea, end)
def prev_ins(self, ea):
'''
Return previous instruction to ea
'''
start = idaapi.cvar.inf.minEA
return idaapi.prev_head(ea, start)
# handlers called from within debug hooks
def handle_function_end(self, ea):
'''
Called when breakpoint hit on ret instruction
'''
function_name = GetFunctionName(ea)
caller = self.format_caller(self.get_caller())
if function_name:
header = "At function end: %s (0x%x) " % (function_name,ea) + "to " + caller
raw_context = self.get_context(ea=ea)
else:
header = "At function end - unknown function (0x%x) " % ea + "to " + caller
raw_context = self.get_context(ea=ea, depth=0)
if self.colors:
SetColor(ea, CIC_ITEM, self.ITEM_COLOR)
(context_full, context_comments) = self.format_normal(raw_context)
if self.delete_breakpoints:
DelBpt(ea)
if self.comments and (self.overwrite_existing or ea not in self.visited):
self.add_comments(ea, context_comments, every = True)
self.visited.append(ea)
self.output_lines([ header ] + context_full + [ "" ])
def handle_return(self, ea):
'''
Called when breakpoint hit on next-to-call instruction
'''
# need to get context from within a called function
function_call = self.function_calls[ea]
ret_shift = function_call['ret_shift']
raw_context = self.get_context()
#raw_context = self.get_context(stack_offset = 0 - ret_shift, depth=function_call['num_args'] - ret_shift) # no stack here ?
sp = self.get_sp()
sp = sp - ret_shift
if self.saved_contexts.has_key(sp):
saved_context = self.saved_contexts[sp]['ctx']
func_name = self.saved_contexts[sp]['func_name']
del self.saved_contexts[sp]
else:
func_name = function_call['func_name']
self.output("WARNING: saved context not found for stack pointer 0x%x, assuming function %s" % (sp, function_call['func_name']))
saved_context = None
header = "Returning from call to %s(), execution resumed at %s (0x%x)" % (func_name, format_offset(ea), ea)
(context_full, context_comments) = self.format_return(raw_context, saved_context)
if self.comments and (self.overwrite_existing or ea not in self.visited):
self.add_comments(ea, context_comments)
self.visited.append(ea)
self.output_lines([ header ] + context_full + [ "" ])
def handle_function_start(self, ea):
'''
Called when breakpoint hit on the beginning of a function
'''
name = GetFunctionName(ea)
caller_ea = self.get_caller()
caller_offset = self.format_caller(caller_ea)
caller_name = format_name(caller_ea)
header = "At function start: %s (0x%x) " % (name,ea) + "called by %s" % caller_offset
raw_context= self.get_context(ea=ea)
if self.colors:
SetColor(ea, CIC_FUNC, self.FUNC_COLOR)
# update data for graph
if not self.calls_graph.has_key(ea):
self.calls_graph[ea] = {}
self.calls_graph[ea]['callers'] = []
self.calls_graph[ea]['callers'].append({ 'name' : caller_name, 'ea' : caller_ea, 'offset' : caller_offset })
self.calls_graph[ea]['name'] = name
(context_full, context_comments) = self.format_normal(raw_context)
if self.comments and (self.overwrite_existing or ea not in self.visited):
self.add_comments(ea, context_comments, every = True)
self.visited.append(ea)
self.visited.append(ea)
self.output_lines([ header ] + context_full + [ "" ])
def handle_generic(self, ea):
'''
Called when breakpoint hit on anything else besides the above and below
'''
header = "Address: 0x%x" % ea
# no argument dumping if not function
raw_context = self.get_context(ea=ea, depth=self.depth)
(context_full, context_comments) = self.format_normal(raw_context)
if self.colors:
SetColor(ea, CIC_ITEM, self.ITEM_COLOR)
if self.comments and (self.overwrite_existing or ea not in self.visited):
self.add_comments(ea, context_comments)
self.visited.append(ea)