Byakugan - Increase Your Sight
Pusscat Lin0xx
NOTE: If you trust me, skip to 4. - I've already included built libs.
A. Building / Installation
1. Requirements
a. WDK
b. Debugging Tools For Windows
- Install to C:\windbg\ - or injectsu will not be found
- Make sure to install with the custom setting
- Explicitly choose to install the SDK
2. Building the libraries
a. Open a WDK build environment for the proper windows version
b. Go to the byakugan base directory
c. type: setup
3. Installation (self built)
a. copy injectsu\i386\injectsu.dll C:\windbg\
b. copy bin\detoured.dll C:\windows\system32\
c. copy i386\byakugan.dll C:\windbg\
4. Installation (Prebuilt binaries)
a. copy bin\<platform>\injectsu.dll C:\windbg\
b. copy bin\<platform>\detoured.dll C:\windows\system32\
c. copy bin\<platform>\byakugan.dll C:\windbg\
B. Deployment:
1. Start up windbg and attach to (or start up) a new process
a. Ensure that both process are at the same priv level,
so they can both access the named pipe
b. Load the byakugan dll:
!load byakugan.dll
c. Display options with !byakugan command if desired
C. Testing:
1. testPattern
a. This tests the pattern matcher in byakugan
b. Build and run in windbg
c. on crash you should be able to type:
!pattern_offset 500
And have it give you the registers you control,
and at what offset into the buffer they occur
2. testTenketsu
a. This tests the heap visualization in byakugan
b. Build and run in windbg
c. On the first break, type
!tenketsu listHeaps
to find the heap containing the chunks you see (should say 11),
then type
!tenketsu listChunks <heap base>
to list the chunks information
d. Let it go, then when it breaks again, check the chunks again,
and it should show half of them as freed. You can for fun try to
find out what that extra allocation is for. Should be pretty simple.
D. Usage:
1. Tenketsu (Heap Visualization)
a1. Load tenketsu heap logging with:
!tenketsu log <logname.xml>
OR
a2. Load tenketsu heap modeling with:
!tenketsu model
b. When process is broken, display heaps with
!tenketsu listHeaps
c. Display chunks with
!tenketsu listChunks <heap base>
2. Jutsu (Buffer Handling)
a. Register input with !jutsu identBuf <bufType> <bufname> <VALUE> <size>
1. Viable types are ascii, msfpattern, and file
ascii requires a name, and pattern, but no size
file takes the file path as a VALUE and requires a size argument
msfpattern requires no value argument
Depending on the TYPE, the rest of the command may have different parts.
Lets examine the currently supported types:
ASCII
The ascii type acts in the same way as you're used to. It requires a name,
and a value which will be tracked, but no size. The string will be null terminated as normal.
!jutsu identBuf ascii myAsciiBuf CatImAKittyCatAndIDanceDanceDance
msfPattern
The msfpattern input type has been enhanced to allow for you to provide a custom
name. It requires a name and a size, but no value. Future enhancements may involve
multiple msfpatterns starting where the last left off in the pattern so as to not
confuse multiple pattern buffers with one another. The format looks like this:
!jutsu identBuf msfpattern myMsfPattern 16
File
The file input type will suck in a file of any format and register it as a tracked
buffer. It requires a name, and takes the file path as a value. It also requires a
size to be input. Future enhancements may include ability to provide an offset into
the file to start reading from. Let me know if you'd like to see this. Currently
though, the format looks like:
!jutsu identBuf file myFileBuf C:\msf3\input.bin 64
Note that listing non-ascii buffers with !jutsu listBuf may result in some funny output,
but this wont break anything...
To load an 010 map file, (the output from a parsed file), use identBufFile:
!jutsu identBufFile inputFile mapFile
This will load the inputFile as many seperate buffers broken up as the 010 template has parsed
it, naming it as the template has named each part.
c. List registered buffers with !jutsu listBuf
d. Remove registered buffers with !jutsu rmBuf <name>
e. After crash, type !jutsu hunt to find out:
1. What buffer caused a crash
2. What registers you've overwritten (and if pattern, at what offset)
3. What registers point at what buffers
4. What corruption has occured (toupper, tolower, etc)
f. Use !jutsu findReturn to find valid return addresses
1. hunt will use all knowledge about controlled registers and buffer offsets
to find all possible usable return addresses
g. Use !jutsu searchOpcode to find opcodes in executable memory
1. delimit instructions with pipes - example:
0:000> !jutsu searchOpcode pop ecx | pop ecx | ret
[J] Searching for:
> pop ecx
> pop ecx
> ret
[J] Machine Code:
> 59 59 c3
[J] Opcode sequence found at: 0x004012f9
h. Use !jutsu searchVtptr to find ptr -> ptr - x -> ptr -> opcodes
Use this just like searchOpcode, except with the second ptr offset
as the first argument:
if your crash looks like:
mov eax, [ebx]
push ebx
call [eax+4]
Where you control ebx, and esp+0x14 points at a buffer you own,
you would use:
!jutsu searchVtptr 4 add esp, 0x14 | ret
0x75cb4b36 -> 0x10450107 -> 0x100ffc08 -> sequence
0x6bb322a6 -> 0x1045891b -> 0x100ffc08 -> sequence
You may then use 0x75cb4b36 or 0x6bb322a6 for your vtable overwrite
i. use !jutsu trackVal to find and primitive values in memory
3. Mushishi (Anti-debugging detection / removal)
a. Not much in here now, but growing
b. !mushishi detect - detects several methods
c. !mushishi defeat - defeats known defeatable methods
4. Symport (Import IDA map files into windbg - map files contain all custom names)
a. !symport moduleName mapFilePath
0:001> !symport calc C:\Users\lgrenier\calc.map
[S] Adjusting symbols to base address of: 0x calc (00680000)
[S] Failed to add synthetic symbol: ?bFocus@@3HA
[S] Failed to add synthetic symbol: ?machine@@3PAY04DA
[S] Failed to add synthetic symbol: ?init_num_ten@@3U_number@@A
[S] Failed to add synthetic symbol: ?init_p_rat_exp@@3U_number@@A
[S] Successfully imported 566 symbols.
4eb35b5c1d