A Diceware passphrase generator extension, implemented in JavaScript, accessible directly from your browser. This uses the Cryptographically Secure Pseudo Random Number Generator (CSPRNG) in your browser as its source of entropy instead of rolling physical dice.
- All random number generation is done in your browser using window.crypto.getRandomValues()
- Single page JavaScript application with no communication back to a server
- Git tags and commits are signed with my public code signing key
- Can be run without a network connection. No logging or analytics
- All assets are served locally from the addon folder
- All CSS and JS elements used have Subresource Integrity hashes
- Support for many language specific word lists
It may just be the closest thing to rolling your own dice. You can do that too of course, and just use this addon as a quick way to lookup your passphrase in the word lists.
Just open the plugin by clicking on its icon. If you choose a new language or click the green button, a new 7 words passphrase will be generated. Each generation rolls a set of five virtual dice for each word. Words are chosen from the included Diceware word lists.
By default, a 7 words passphrase is generated. This is about ~77.55 bits of entropy (~12.92 bits/word, ~10 bits/letter, and ~5.16 bits/symbol). For a professional adversary can guess passwords at the rate of a 1,000,000,000,000 keys/second, an exhaustive brute-force search on 50% of the total keyspace might take ~30,704,711 hours or ~1,279,363 days or ~3,505 years.
Depending on your security requirements, you may want to add a word or a symbol to the generated passphrase.
To improve acceptance by online services, the first letter of the first word is now capitalized.
If you are security conscious you are of course encouraged to download the source code for this addon and check the code yourself. The main part is located here.
#under a black hood with a printout of the Diceware word list available #here. No computers needed!
Not really kidding
Most, if not all, of the commits and tags in the repository for this code are signed with my PGP/GPG
code signing key. I have uploaded my code signing public keys to GitHub and you can now verify those
signatures with the GitHub UI. See this list of
commits and look for the
Verified tag next to each commit. You can click on that tag for additional information.
You can also clone the repository and verify the signatures locally using your own GnuPG installation. You can find my certificates and read about how to conduct this verification at https://keybase.io/gromain.
This addon uses a Makefile to produce the artefact for testing the addon or releasing it.
make zip creates the artefact for testing or releasing the addon. To test it, simply go to
about:debugging in your browser, chose the tab "This Firefox" and load the generated zip file.
make clean removes the artefact and make update updates the created zip file with your changes.
Bug reports and pull requests are welcome on GitHub at https://github.com/gromain/Diceware-Passphrase-Generator. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the Contributor Covenant code of conduct.
#used
(c) 2022 Romain Bazile <romain@bazile.io> (https://romain.bazile.io/)
This addon is available as open source under the terms of the MIT License.
Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the LICENSE.txt file for the specific language governing permissions and limitations under the License.
This implementation was inspired by the very nicely done https://github.com/yesiamben/diceware. I took the opportunity to upgrade some security aspects and the UI.
This addon is very largely based on the work of Glenn Rempe, available at https://github.com/grempe/diceware. Many thanks for the provided source code.