fix(origin): issue leaves as CA:FALSE, and trust them on the box that serves them - #18
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ralyodio merged 1 commit intoAug 9, 2026
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… serves them `openssl req -x509` defaults to basicConstraints=CA:TRUE, and setup-origin.sh never overrode it. Every origin this script has ever created is therefore serving a certificate that is marked as a certificate authority. That matters because this certificate is meant to be trusted *directly* — it is its own anchor, which is the whole point of a pinned self-signed origin. An anchor marked CA:TRUE may issue for any name in the world. The SAN bounds what the certificate speaks for; it does not bound what a key trusted as an authority may go on to sign. So trusting one of these to reach `chovy.hacker` also hands its holder google.com. CA:FALSE with a single-name SAN is the shape that makes direct trust a bounded grant. Re-running fixes an already-published certificate for free: the key is reused and the pin is over the key, so the registry needs no update and no client holding the old pin breaks. Also here: - `--all` re-issues every name the box already has a key for, so repairing a fleet is one command with nothing to type and mistype. - the certificate is trusted on this machine once it is issued. The machine serving a Moshpit name is usually one somebody browses it from, and until now `curl https://<name>` failed to verify there. The pinned-TLS proxy cannot fix that case: it works by owning 443 on loopback, and on an origin nginx already has 443 — a second bind gets EADDRINUSE. Trusting the leaf needs no port. - a name is checked against a hostname charset before it becomes a path under /etc/ssl, /etc/nginx and /usr/local/share/ca-certificates, as root. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
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vu1nz Security Review0 finding(s) in PR #? No security issues found. |
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The bug
openssl req -x509 defaults to basicConstraints=CA:TRUE, and setup-origin.sh never overrode it. Every origin this script has ever created serves a certificate marked as a certificate authority. On the dev box, all three do:
$ openssl x509 -in <served> -noout -ext basicConstraints X509v3 Basic Constraints: critical CA:TRUEThis certificate is meant to be trusted directly — it is its own anchor, which is the point of a pinned self-signed origin. An anchor marked CA:TRUE may issue for any name. The SAN bounds what the certificate speaks for; it does not bound what a key trusted as an authority may go on to sign. Trusting one of these to reach chovy.hacker also hands its holder google.com.
The fix
CA:FALSE + single-name SAN + serverAuth. That is the shape where direct trust is a bounded grant — verified in the tests to still work as its own anchor, which is what a stock client needs.
Repair is free. The key is reused and the pin is over the key, so re-issuing leaves the published pin untouched: no registry update, no flag day, no client holding the old pin breaks.
Also here
Tests
tests/setup-origin.test.ts, 8 new. The extension flags are read out of the script rather than restated, so a test cannot pass while the script mints something else — which is exactly the failure mode being guarded against. Full suite 69/69.
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