Chromium

Chromium is an open-source browser project that aims to build a safer, faster, and more stable way for all users to experience the web.

The project's web site is https://www.chromium.org.

Documentation in the source is rooted in docs/README.md.

Learn how to Get Around the Chromium Source Code Directory Structure .

For historical reasons, there are some small top level directories. Now the guidance is that new top level directories are for product (e.g. Chrome, Android WebView, Ash). Even if these products have multiple executables, the code should be in subdirectories of the product.

JSCapsule

Chromium Version

Chromium=83.0.4103.97
V8=8.3.110.9

Code Repo

We now have two branches. One is master which only contains the instrumented files. The other is dev which is an orphan branch of Chromium version stated at the beginning.

Master

The structure of the master is as below. The ./src directory is exactly the same structure of path/to/chromium/src but only has instrumented files.

.
|-- src/
|-- utils/

Dev

We don't keep the git history of Chromium in this branch, so we need a procedure to work with this branch, AKA, the working branch.

1. Fetch the Chromium code by following the instruction.
2. Checkout to the correct version by git checkout tags/83.0.4103.97 and run gclient sync -D afterwards.
3. Then add one more remote to Chromium's repo by git remote add github git@github.com:jallen89/JSCapsule.git.
4. Do a git fetch github dev to get the information of the added repo.
5. Now you can checkout to the dev branch by doing git checkout -b dev github/dev.
6. When you need to pull/push changes, remember to do git pull/push dev github/dev.
7. If you want to work in a different branch, just branch from the github/dev. When you finish the work, please submit a Pull Request and merge the changes into github/dev.

It's important that every time you need to run gclient sync -D in tags/83.0.4103.97 when you switch to other Chromium tags or master

Misc

1. The log now writes to file. chromium/src/out/[Debug|Release|Default]/path/to/chromium --no-sandbox --forensic-log-file=/path/to/logfile to start recording. /path/to/logfile should be accessible from chromium. If --forensic-log-file is not provided, it writes to /tmp/jscapsule.log by default.

2. JSCapsule cannot be compiled using component builds. You need to update the args.gn file to disable component builds. In args.gn set is_component_build=false.

Recording

The script record.sh is used for recording a website:

./record.sh https://www.example.com example

This would record https://www.example.com (NOTE: always used the entire URL) and store the logs in example<pid>.

Replaying

To replay a website, open two terminals.

In the first terminal, run the following command:

./replay.sh example.replay &> example.logs

In the second terminal, run the following command in the forensic_utils directory:

./run.py load-logs ../example<pid>

NOTE: If the recording used multiple process (e.g., multiple tabs or iframes in w/ different origins), you will need to run the following command

./run.py load-logs --merge ../example<pid>*