joern-lib 0.9.1

Python library to interact with Joern server

Introduction

This project offers a high level python library to interact with a Joern server. Several API methods including integration with NetworkX are offered to perform code analysis and research on complex code bases in a pythonic manner from cli and from notebooks.

pip install joern-lib

The repository includes docker compose configuration to interactively query the joern server with polynote notebooks.

Usage

Run joern server and polynote locally.

git clone https://github.com/appthreat/joern-lib.git
# Edit docker-compose.yml to set sources directory
docker compose up -d

# podman-compose up --build

Navigate to http://localhost:8192 for an interactive polynote notebook. You could open one of the sample notebooks from the contrib directory to learn about Joern server and this library.

Common steps

python -m asyncio

Execute single query

from joern_lib import client, workspace, utils
from joern_lib.detectors import common as cpg

connection = await client.get("http://localhost:9000", "http://localhost:7072", "admin", "admin")

# connection = await client.get("http://localhost:9000")

res = await client.q(connection, "val a=1");

# {'response': 'a: Int = 1\n'}

Execute bulk query

res = await client.bulk_query(connection, ["val a=1", "val b=2", "val c=a+b"]);
# [{'response': 'a: Int = 1\n'}, {'response': 'b: Int = 2\n'}, {'response': 'c: Int = 3\n'}]

Workspace

List workspaces

res = await workspace.ls(connection)

Get workspace path

res = await workspace.get_path(connection)
# /workspace (Response would be parsed)

Check if cpg exists

await workspace.cpg_exists(connection, "NodeGoat")

Import code for analysis

res = await workspace.import_code(connection, "/app", "NodeGoat")
# True

Import an existing CPG for analysis

res = await workspace.import_cpg(connection, "/app/sandbox/crAPI/cpg_out/crAPI-python-cpg.bin.zip", "crAPI-python")

Create a CPG with a remote cpggen server

res = await workspace.create_cpg(connection, "/app/sandbox/crAPI", out_dir="/app/sandbox/crAPI/cpg_out", languages="python", project_name="crAPI-python")

CPG core

List files

res = await cpg.list_files(connection)
# list of files

Print call tree

res = await cpg.get_call_tree(connection, "com.example.vulnspring.WebController.issue:java.lang.String(org.springframework.ui.Model,java.lang.String)")
utils.print_tree(res)

Java specific

from joern_lib.detectors import java

List http routes

await java.list_http_routes(connection)

JavaScript specific

from joern_lib.detectors import js

List http routes

await js.list_http_routes(connection)

Name of the variable containing express()

await js.get_express_appvar(connection)

List of require statements

await js.list_requires(connection)

List of import statements

await js.list_imports(connection)

List of NoSQL DB collection names

await js.list_nosql_collections(connection)

Get HTTP sources

await js.get_http_sources(connection)
await js.get_http_sinks(connection)

AWS

Requires TypeScript project

await js.list_aws_modules(connection)

Troubleshooting

No response from server

If Joern server stops responding after a while restart docker.

docker compose down
docker compose up -d

Websockets connection closed error

Adding asyncio.sleep(0) seems to fix such errors.

# Workaround to fix websockets.exceptions.ConnectionClosedError
await asyncio.sleep(0)

pygraphviz refuses to install

pygraphviz/graphviz_wrap.c:2711:10: fatal error: graphviz/cgraph.h: No such file or directory
   2711 | #include "graphviz/cgraph.h"
        |          ^~~~~~~~~~~~~~~~~~~
  compilation terminated.
  error: command '/usr/bin/gcc' failed with exit code 1

Install graphviz-devel or graphviz-dev package for your OS. See here