https://github.com/wapiflapi/villoc

Visualization of heap operations.
https://github.com/wapiflapi/villoc

Last synced: 3 months ago
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Visualization of heap operations.

• Host: GitHub
• URL: https://github.com/wapiflapi/villoc
• Owner: wapiflapi
• License: mit
• Created: 2015-04-19T13:41:10.000Z (almost 10 years ago)
• Default Branch: master
• Last Pushed: 2020-07-07T21:59:48.000Z (over 4 years ago)
• Last Synced: 2024-08-01T09:23:23.067Z (6 months ago)
• Language: Python
• Size: 52.7 KB
• Stars: 600
• Watchers: 33
• Forks: 72
• Open Issues: 5
• Metadata Files:
  • Readme: README.md
  • License: LICENSE.md

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• awesome-rainmana - wapiflapi/villoc - Visualization of heap operations. (Python)

README

        
# Villoc

Villoc is a heap visualisation tool, it's a python script that renders a static

html file. An example can be seen here: http://wapiflapi.github.io/villoc/, this

is villoc running on an exploit of PlaidCTF 2015's challenge PlaidDB.

## How to

The easiest way to use villoc is probably to run the following command and open

out.html in a browser.

```shell

ltrace ./target |& villoc.py - out.html;

```

It is probably a good idea to disable ASLR for repeatable results and to use a

file to pass the ltrace to villoc because otherwise the target's error output

will be interleaved and might confuse villoc sometimes.

```shell

setarch x86_64 -R ltrace -o trace ./target; villoc.py trace out.html;

```

## Using DynamoRIO

The problem with ltrace is that it doesn't track calls to malloc from

other libraries or from within libc itself.

Please check https://github.com/wapiflapi/villoc/tree/master/tracers/dynamorio

for (easy!) instructions for using a DynamoRIO tool to achieve full tracing.

## Annotations

Villoc's input should look like ltrace's output, other tracers should output

compatible logs. Villoc also listens to annotations of the following form:

``` text

@villoc(comma separated annotations) = `

```

When using this it's possible to mark certain block as being significant which

makes analyzing villoc's output that much easier.

### Annotations from C code through DynamoRIO.

When using the dynamorio tracer there is a hack to easily inject annotations

from a target's source code:

``` C

sscanf("Format string %d %d, FOO %s", "@villoc", 1, 2, "BAR");

```

Will inject `Format string 1 2` into villoc's log and add the `FOO`

and `BAR` tags to the block affected by the next memory operation.

![image](https://pbs.twimg.com/media/DxnUnRzWwAU4kcD?format=jpg&name=large)

## Which malloc

This has been made with glibc's dl_malloc in mind. But it should work for other

implementations, especially if you play with the `--header` and `--footer`

options to indicate how much overhead the targeted malloc adds to the user data.