The Geomys testing Mirroring Cosigner

[Filippo Valsorda]

Hello fellow humans,

Geomys is happy to announce a testing Mirroring Cosigner, which can be used from today to test tlog-mirror clients and MTC CAs, and that we plan to submit to the Chrome Testing and Validation Trust Store once that process is ready.

Cosigner ID: 66252.128.0

Submission prefix: https://witness.navigli.sunlight.geomys.org/

Monitoring prefix: https://witness.navigli.skylight.geomys.org/mirror/ 

JSON (w/ key): https://witness.navigli.sunlight.geomys.org/mirror/mirror.v0.json

Accepted logs: https://github.com/geomys/magnolia/blob/main/staging/mirror.log-list.txt

This Mirroring Cosigner runs the main branch of Sunlight, which now includes implementations of c2sp.org/tlog-mirror, and of the read endpoint and sign-subtree extensions of c2sp.org/tlog-witness, as well as the new ML-DSA-44 c2sp.org/tlog-cosignature.

Accepted logs are configured using the Witness Network log-list format, and are fetched every 15 minutes from the specified file, which you can send PRs to! We expect the mechanism to change once the ecosystem develops an official way to broadcast issuers and logs.

To make it easier to add an MTC issuance log to that log-list, we—well, Sol—made a quick client-side tool: https://htmlpreview.github.io/?https://github.com/FiloSottile/mostly-harmless/blob/main/mtc-log-list/index.html

The mirror shares state with a witness named witness.navigli.sunlight.geomys.org, which signs (with a separate key), the checkpoints submitted via add-checkpoint, and serves them with a https://witness.navigli.skylight.geomys.org/ monitoring prefix. That witness is part of the staging Public Witness Network.

This being testing/staging, you should expect it to break sometimes as it will run the development branch of Sunlight, and state might be wiped if necessary.

Alla prossima,

Filippo