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feat(canokey): sudo, SSH, LUKS and OpenPGP setup for daily use (#516)
Use the CanoKey for daily authentication on idols-ai and shoukei, with the existing passwords, passphrases and per-host SSH keys as fallback. - sudo: pam_u2f with a shared origin (pam://ryan4yin) and a Nix-store authfile built from myvars.canokeyU2fKeys; the primary key is registered and touch-to-sudo works on idols-ai. - SSH: one resident ed25519-sk key (application=ssh:ryan4yin) exported to ~/.ssh/id_ed25519_sk; GitHub tries it before the per-host key. - shoukei LUKS: fido2-device=auto with token-timeout=10s. Update nixos-apple-silicon (linux-asahi 7.2.14), whose initrd adds thunderbolt_apple and reset_apple_cio so USB-C comes up before unlock. - GPG: scdaemon disable-ccid so it uses pcscd. - docs/security-keys.md: setup, PINs, enrollment, backup key and recovery; deduplicate the FIDO notes left by #515. Assisted-by: Claude Code (claude-opus-5-5)
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@@ -17,6 +17,7 @@ those entry points.
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- [Security](SECURITY.md) — threat model, trust boundaries, implemented controls and audits.
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- [Backups](BACKUP.md) — backup layers, password model, retention and restore procedure.
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- [Hardware security keys](security-keys.md) — CanoKey/YubiKey setup, backup keys and recovery.
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- [Workarounds and known gaps](WORKAROUNDS.md) — pins, temporary workarounds and removal conditions.
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- [BIOS settings](bios.md) — firmware settings for the physical hosts.
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- [Wake-on-LAN](wake-on-lan.md) — firmware prerequisites, NixOS setup and wake commands.
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+18
-22
@@ -33,18 +33,19 @@ small, reversible controls and narrow exceptions; benchmark before adopting expe
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## Architecture and trust boundaries
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| Boundary | Current design | Limitation |
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| --------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
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| Administration | Key-based SSH; root key login retained for Colmena/MicroVM deployment; only keys declared in Nix are honoured, and no password or keyboard-interactive login; remote-builder host keys only reach `nix-daemon` | Deployment credentials are root-equivalent file keys, usable by any same-user process through the desktop SSH agent; one stolen key reaches every host |
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| Host network | Shared nftables firewall trusts the home LAN, tailnet interface and local Podman bridge; IPv6 link-local is accepted | These are broad trust zones, not service-level least privilege; router exposure and tailnet ACLs require separate verification |
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| Monitoring | node/smartctl exporters bind the host LAN IPv4 (9100/9633); firewall rules restrict exporter ports 9100, 9835 and 9633 to the monitoring host over IPv4. RAPL counters are exposed only on x86 server hosts, to `node-exporter` through the `rapl` group. | nvidia_gpu_exporter (9835) still binds wildcard; the IPv6 denial for those three ports is in the shared firewall; current running hosts require separate verification. The node_exporter account can measure package energy for local side channels; interactive users, desktops, and guests keep the kernel-default root-only permission. |
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| VM hosts | shoryu, shushou and youko run guests behind `br0`; ruby/kana are libvirt guests | A bridge is not network isolation; host compromise affects its guests |
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| k3s | Three control-plane and three worker MicroVMs; Cilium, API VIP and NFS CSI | Cluster-admin, privileged/host-mounted pods and writable NFS data are powerful trust boundaries |
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| MicroVM storage | Host store shared read-only through virtiofs; guest `/etc`, `/var` and `/home` persisted in separate images | Read-only store does not isolate the host-side virtiofs implementation or protect writable guest state |
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| Desktop apps | Selected apps use nixpak/bubblewrap; Podman is rootless | Rules and shared directories vary per app; user namespaces are needed for these sandboxes |
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| Secrets | agenix declarations here, encrypted data in the private nix-secrets repository | Recipients and plaintext file permissions must be reviewed; root on a recipient can read its decrypted secrets |
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| Supply chain | Locked flake inputs; explicit binary-cache trust keys on NixOS; normal user is not a Nix trusted-user | A trusted cache or imported Nix module can supply code executed as root; a lock file is not a security audit |
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| Recovery | NixOS generations, btrbk/restic, hourly read-only snapshots of the REST store, and documented backup procedures | A rollback does not undo compromised data or secrets; backup configuration alone does not prove restore works; the offsite immutable copy is still planned |
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| Boundary | Current design | Limitation |
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| --------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
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| Administration | Key-based SSH; root key login retained for Colmena/MicroVM deployment; only keys declared in Nix are honoured, and no password or keyboard-interactive login; remote-builder host keys only reach `nix-daemon` | Deployment credentials are root-equivalent file keys, usable by any same-user process through the desktop SSH agent; one stolen key reaches every host |
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| Host network | Shared nftables firewall trusts the home LAN, tailnet interface and local Podman bridge; IPv6 link-local is accepted | These are broad trust zones, not service-level least privilege; router exposure and tailnet ACLs require separate verification |
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| Monitoring | node/smartctl exporters bind the host LAN IPv4 (9100/9633); firewall rules restrict exporter ports 9100, 9835 and 9633 to the monitoring host over IPv4. RAPL counters are exposed only on x86 server hosts, to `node-exporter` through the `rapl` group. | nvidia_gpu_exporter (9835) still binds wildcard; the IPv6 denial for those three ports is in the shared firewall; current running hosts require separate verification. The node_exporter account can measure package energy for local side channels; interactive users, desktops, and guests keep the kernel-default root-only permission. |
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| VM hosts | shoryu, shushou and youko run guests behind `br0`; ruby/kana are libvirt guests | A bridge is not network isolation; host compromise affects its guests |
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| k3s | Three control-plane and three worker MicroVMs; Cilium, API VIP and NFS CSI | Cluster-admin, privileged/host-mounted pods and writable NFS data are powerful trust boundaries |
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| MicroVM storage | Host store shared read-only through virtiofs; guest `/etc`, `/var` and `/home` persisted in separate images | Read-only store does not isolate the host-side virtiofs implementation or protect writable guest state |
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| Desktop apps | Selected apps use nixpak/bubblewrap; Podman is rootless | Rules and shared directories vary per app; user namespaces are needed for these sandboxes |
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| Security keys | idols-ai/shoukei use a CanoKey for touch-based sudo (pam_u2f, password fallback), one resident `ed25519-sk` SSH key for GitHub and all hosts, FIDO2 LUKS unlock on shoukei and on-card OpenPGP subkeys; key management happens only in the phone app ([setup](./security-keys.md)) | Touch-only sudo can be triggered by any same-user process; per-host file SSH keys and passphrases stay valid as fallback, so their weaknesses remain until retired |
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| Secrets | agenix declarations here, encrypted data in the private nix-secrets repository | Recipients and plaintext file permissions must be reviewed; root on a recipient can read its decrypted secrets |
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| Supply chain | Locked flake inputs; explicit binary-cache trust keys on NixOS; normal user is not a Nix trusted-user | A trusted cache or imported Nix module can supply code executed as root; a lock file is not a security audit |
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| Recovery | NixOS generations, btrbk/restic, hourly read-only snapshots of the REST store, and documented backup procedures | A rollback does not undo compromised data or secrets; backup configuration alone does not prove restore works; the offsite immutable copy is still planned |
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Sources: [host layout](../hosts/README.md), [k3s deployment](../hosts/k8s/README.md),
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[firewall](../modules/nixos/base/networking/firewall.nix), [SSH](../modules/nixos/base/ssh.nix),
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@@ -332,13 +333,9 @@ isolation. Source review and socket metadata—not reads of private credentials
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Browser media and browserpass are enabled only for Firefox/Chromium/Chrome. Brave Origin and Edge
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are backup browsers with no media grants. browserpass exposes password-store/GPG data and agent
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operations.
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- Firefox/Chromium/Chrome receive FIDO2 security-key passthrough for WebAuthn/passkeys. Host udev
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rules hard-link only FIDO-tagged hidraw nodes into `/dev/fido-hidraw` and remove them on unplug;
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the sandbox binds that directory plus read-only `/sys/class/hidraw` and the udev database. The
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CanoKey KBD and CCID interfaces, other HID devices and raw USB stay outside the sandbox; Brave
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Origin and Edge receive no FIDO2 passthrough. A compromised browser can use the key's FIDO
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interface; the key's PIN and touch policy remain the authentication boundary. Hotplug works for
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host-network Firefox/Chromium; pasta-isolated Chrome needs the key present at launch.
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- Firefox/Chromium/Chrome receive only a security key's FIDO interface (mechanism and limits in the
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[hardening README](../hardening/README.md#limits)). A compromised browser can use that interface;
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the key's PIN and touch policy remain the authentication boundary.
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- Nixpak supplements Chromium's renderer sandbox, which remains enabled. Zoom/WeChat retain their
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FHS runtimes inside the outer boundary; inner mounts cannot recover hidden host resources.
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- Desktop access has limits: GPU drivers remain exposed, PulseAudio permits recording, read-only
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@@ -355,9 +352,8 @@ isolation. Source review and socket metadata—not reads of private credentials
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- Policy/build passes for all nine wrappers. Interactive validation passed for Firefox, Chrome,
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Chromium, Brave Origin, Edge, QQ, Telegram and Zoom; the Chromium smoke test also validates
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renderer sandboxing, environment clearing, bind scope and profile persistence. WeChat's
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interactive Wayland check remains pending. FIDO2 browser passthrough passed WebAuthn with the
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CanoKey in Firefox and Chrome; Chromium and plugging the key in after launch still need
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validation. See the [runtime validation](../hardening/tests/runtime-validation.md).
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interactive Wayland check remains pending. See the
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[runtime validation](../hardening/tests/runtime-validation.md).
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#### Agent-first diagnostics by host role
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@@ -0,0 +1,235 @@
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# Hardware security keys
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How the CanoKey (or a YubiKey) is set up and used on the desktops: initial setup, adding a backup
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key, and recovery. Commands here are the single source; the Nix files only point to this page.
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Scope: **idols-ai** and **shoukei** (`modules.desktop.canokey.enable`). frieren only shares the
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GnuPG `scdaemon` setting; servers never use a key.
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## Principle
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Management and use happen on different devices.
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- **PCs only use the key:** WebAuthn/passkeys, sudo, SSH, LUKS unlock and OpenPGP (pass).
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- **Management happens only in the phone app** (CanoKey Console on iOS/Android): every PIN change,
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touch policies, application and factory reset, device settings. The CanoKey Admin PIN is never
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typed on a PC; the OpenPGP Admin PIN is typed once, for `keytocard`.
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- Sandboxed browsers see only the FIDO HID interface, never raw USB or CCID, so the WebUSB console
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is unreachable from them ([hardening](../hardening/README.md)). Unsandboxed software is trusted;
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if it is malicious, the PC is compromised regardless.
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| Use | Config | Daily use | Fallback without the key |
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| ------------ | ------------------------------------------------------------------------------------------------------------------ | ---------------------------------------- | ----------------------------------------- |
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| Browsers | [nixpak FIDO2 passthrough](../hardening/nixpaks/default.nix) | FIDO2 PIN and/or touch, as the site asks | site recovery codes, other registered key |
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| sudo | [canokey.nix](../modules/nixos/desktop/canokey.nix), registrations in [vars](../vars/default.nix) `canokeyU2fKeys` | touch | password |
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| SSH | [ssh.nix](../home/base/tui/ssh.nix), public keys in [vars](../vars/default.nix) `mainSshAuthorizedKeys` | touch per connection | per-host file keys |
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| shoukei LUKS | [hardware-configuration.nix](../hosts/12kingdoms-shoukei/hardware-configuration.nix) `crypttabExtraOpts` | FIDO2 PIN + touch | passphrase (prompted after 10 s) |
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| pass / GPG | [gpg](../home/base/tui/gpg/default.nix) `scdaemonSettings.disable-ccid` | OpenPGP PIN once per plug-in, then touch | off-card subkey backup |
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Login (greetd) stays password-based: the password also unlocks GNOME Keyring.
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## 1. Device setup
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### 1.1 Replace every default secret first
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Each application has its own secrets: separate values, separate retry counters (3 on released
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firmware), and blocking one does not affect the others. The defaults are public (from the
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[CanoKey user guide](https://docs.canokeys.org/userguide/)), so change all of them in the phone app
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(CanoKey Console) **before using the key for anything**, including applications you do not use: with
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a default PIN or management key, anyone holding the key can use or rewrite that application.
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| Application | Secret | Default | Protects | Set it to | Typed |
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| ----------- | ----------------- | ---------------------- | ---------------------------------------------------------- | --------------------------------------------------------------------- | --------------- |
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| Device | CanoKey Admin PIN | `123456` | settings, per-application and factory reset | random, 12+ characters (6–64); save offline | phone only |
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| WebAuthn | FIDO2 PIN | unset | passkeys, LUKS unlock, SSH key creation and export | memorable, 8+ characters (4–63); memorize | daily, browsers |
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| OpenPGP | PIN | `123456` | decrypt (pass), sign, authenticate | memorable, 8+ characters (6–64), not the FIDO2 PIN; memorize | daily, pinentry |
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| OpenPGP | Admin PIN | `12345678` | key import (`keytocard`), touch policy, unblocking the PIN | random, 12+ characters (8–64); save offline | setup only |
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| OpenPGP | Reset Code | unset | unblocking the PIN without the Admin PIN | leave unset (the Admin PIN also unblocks), or random and save offline | recovery only |
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| PIV | PIN / PUK | `123456` / `12345678` | PIV keys / unblocking the PIV PIN | 8 random digits each (maximum 8); do not save | never |
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| PIV | management key | `0102030405060708` × 3 | writing PIV keys and certificates | the app's random management key button; do not save | never |
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| OATH | none: no password | — | anyone holding the key can read its TOTP/HOTP codes | — | — |
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Every PIN locks after 3 wrong attempts, so length matters less than not reusing a value. Generate
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the random values with the phone's password manager; "save offline" means that password manager or
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paper, never `pass`: `pass` itself is decrypted by this key. The FIDO2 PIN is typed into browsers,
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the least trusted place, so it must not also unlock pass.
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PIV is unused, so its secrets are random and discarded: PIV is then locked rather than open with
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public defaults. To use PIV later, reset just the PIV application in the phone app (needs only the
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CanoKey Admin PIN), which restores the defaults.
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### 1.2 Firmware and settings (phone app)
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Touch policies are enforced **only over USB, not NFC**. OpenPGP and PIV stay reachable over NFC on
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released firmware, but each NFC tap is a new card session, so their PINs are still required.
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1. Check the firmware version. U2F (sudo) does not work on 3.0.0; 3.0.2 and later are fine. The
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newest public release is canokey-core [3.0.3](https://github.com/canokeys/canokey-core/tags).
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2. Settings on released firmware (the user guide lists LED, NDEF and WebUSB login page):
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| Setting | Choice | Why |
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| ----------------- | -------------------------------------- | ------------------------------------------------------------------------- |
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| LED | on | an unexpected blink means something requested a touch |
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| WebUSB login page | off | the console is not used on PCs |
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| NDEF | off, or read-only if the app offers it | default is enabled; anyone nearby can read it, and rewrite it if writable |
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3. The user guide also documents options for **firmware 3.1.0**, which has no public release yet
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(only the docs mention it; canokey-core's `dev` branch is unversioned). If the app shows them:
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| Option | Choice | Why |
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| ------------------------------------------- | --------------------------------------------- | ------------------------------------------ |
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| OpenPGP / PIV over NFC | off, unless the phone needs OpenPGP | touch is not enforced over NFC |
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| Password/HOTP keyboard output, PIV switches | off unless used | smaller attack surface |
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| WebAuthn `alwaysUv` | off | on breaks U2F, which sudo uses |
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| WebAuthn minimum PIN length | 6–8 | the PIN locks after a few failures |
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| Long-press reset | off, unless the app documents it as PIN-gated | keeps reset a phone-side management action |
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## 2. Enroll a key
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Only after section 1.1. Do these in order; each step can be rolled back on its own. Only the OpenPGP
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step is irreversible.
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### Browsers (WebAuthn / passkeys)
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Nothing to enroll on the PC. Register the key on each site, preferably as a passkey. After a first
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deploy via `switch` without reboot, see the FIDO2 notes in the
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[hardening README](../hardening/README.md#limits).
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### sudo
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```bash
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# pamu2fcfg is installed once canokey.nix is deployed; before that:
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# Long options: some nix versions expand short flags such as -i after --command.
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nix shell nixpkgs#pam_u2f --command \
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pamu2fcfg --nouser --origin=pam://ryan4yin # touch the key
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```
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Add the printed `KeyHandle,PublicKey,es256,+presence` string to `canokeyU2fKeys` in
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[vars/default.nix](../vars/default.nix) (public data; a leading `:` is accepted) and deploy. sudo
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then shows "Please touch the device"; without the key it asks for the password. While the list is
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empty, sudo is unchanged.
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Every host shares the origin `pam://ryan4yin`, so one registration covers idols-ai and shoukei.
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### SSH
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One SSH key, used for GitHub and every host, lives on the key as a resident credential:
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```bash
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ssh-keygen -t ed25519-sk -O resident -O application=ssh:ryan4yin -C ryan@canokey
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```
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This writes `~/.ssh/id_ed25519_sk` on the machine that runs it. On each other desktop, export the
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key handle to ssh's default identity:
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```bash
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cd ~/.ssh && ssh-keygen -K \
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&& mv id_ed25519_sk_rk_ryan4yin id_ed25519_sk && mv id_ed25519_sk_rk_ryan4yin.pub id_ed25519_sk.pub
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```
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How it works, and what the prompts mean:
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- The private key never leaves the CanoKey. `~/.ssh/id_ed25519_sk` holds only the credential ID,
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application and public key. Every authentication sends the server's challenge to the key, which
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signs it after a touch; with the key unplugged, ssh skips this identity and tries the next one.
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- **FIDO2 PIN:** asked only when creating the credential and when exporting it with `-K`, not for
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each login. Adding `-O verify-required` at creation would require the PIN for every login too.
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- **Touch:** required for every new connection, including each `git push`/`fetch`. Existing sessions
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and reused connections need none: LAN hosts multiplex for 30 minutes (`ControlMaster` in
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[ssh.nix](../home/base/tui/ssh.nix)). A deploy that opens one connection per host needs one touch
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per host.
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- **File passphrase:** leave it empty. Reading the file already takes your user session, and
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software running as you is trusted (see [Principle](#principle)); it could also capture the
|
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passphrase the next time you type it. A passphrase would cost one prompt per login, not per
|
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connection: `AddKeysToAgent yes` keeps the unlocked handle in the agent, which still asks the key
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for each signature.
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Add the public key to `mainSshAuthorizedKeys` in [vars/default.nix](../vars/default.nix) and to
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GitHub. GitHub tries `id_ed25519_sk` before the per-host key; other hosts try it as a default
|
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identity. Keys already loaded in `ssh-agent` are offered first, so the per-host keys can still win
|
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until they are retired.
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|
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### shoukei LUKS
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|
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Enroll before deploying the crypttab change:
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|
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```bash
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systemd-cryptenroll --fido2-device=list # as the user: shows the key's hidraw node
|
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sudo systemd-cryptenroll --fido2-device=/dev/hidrawN /dev/disk/by-uuid/1c37820e-2501-46e4-bec4-27c28691a5b4
|
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sudo systemd-cryptenroll /dev/disk/by-uuid/1c37820e-2501-46e4-bec4-27c28691a5b4 # list slots
|
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```
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|
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Name the hidraw node instead of `--fido2-device=auto`: libfido2 is built with PC/SC support, so root
|
||||
also finds the key's FIDO applet through pcscd (`pcsc://slot0`) and `auto` stops with "More than one
|
||||
FIDO device found". Unlocking at boot is unaffected: pcscd does not run in the initrd.
|
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|
||||
The default enrollment requires the FIDO2 PIN and a touch; keep it that way, since the key often
|
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travels with the laptop. The passphrase slot stays. Reboot to verify.
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|
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### pass (OpenPGP)
|
||||
|
||||
The password store is encrypted to the `[E]` subkey `0xEF824EB73CFD6CC7`; the primary key is
|
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offline.
|
||||
|
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1. Verify the **off-card backup** of all three subkeys first: `keytocard` replaces the on-disk copy
|
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with a stub.
|
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2. Move the subkeys: `gpg --edit-key 0xCC88591C033F1924`, then `key 1` → `keytocard` (encryption),
|
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and likewise for the signing and authentication subkeys; `save`.
|
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3. Require touch for SIG, DEC and AUT in the phone app's OpenPGP page (or on the PC:
|
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`gpg --card-edit` → `admin` → `uif 1 on`, `uif 2 on`, `uif 3 on`). Decrypt touch matters most:
|
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browserpass gives browsers the GPG agent socket, and without touch a compromised browser could
|
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decrypt the whole store silently after the first PIN.
|
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4. On other machines that still hold on-disk copies, delete them
|
||||
(`gpg --delete-secret-keys '<subkey-fingerprint>!'`) and run `gpg --card-status` so gpg records
|
||||
stubs for the card.
|
||||
|
||||
`keytocard` is the only step that types the OpenPGP Admin PIN on a PC; change it again in the phone
|
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app afterwards.
|
||||
|
||||
## 3. Add a backup key
|
||||
|
||||
A second CanoKey or a YubiKey works the same way; the module name is CanoKey-specific but nothing in
|
||||
it is. On a YubiKey, manage settings with Yubico Authenticator or `ykman`; OpenPGP touch is
|
||||
`ykman openpgp keys set-touch dec on` (and `sig`, `aut`).
|
||||
|
||||
| Use | Backup key step |
|
||||
| ------------ | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
|
||||
| Device | Section 1 again |
|
||||
| Browsers | Register it on every site as an additional security key |
|
||||
| sudo | `pamu2fcfg --nouser --origin=pam://ryan4yin` with only the backup plugged in; append to `canokeyU2fKeys` |
|
||||
| SSH | Create a resident key on it with the same command; add its public key to `mainSshAuthorizedKeys` and GitHub. Use it with `ssh-add -K` (loads resident keys into the agent) instead of exporting a file |
|
||||
| shoukei LUKS | Run the same `systemd-cryptenroll --fido2-device=auto` with only the backup plugged in; it takes the next slot |
|
||||
| OpenPGP | Import the subkeys from the backup into a fresh, temporary `GNUPGHOME`, `keytocard` them onto the backup key, then delete that `GNUPGHOME`. The stubs remember the card serial; after swapping cards run `gpg-connect-agent "scd serialno" "learn --force" /bye` |
|
||||
|
||||
## 4. Lost key or reset
|
||||
|
||||
| Situation | Action | Lost |
|
||||
| ------------------------------------ | ------------------------------------------------------------------------------------------------------------------- | ----------------------------------------------------------------------------- |
|
||||
| Key lost | Remove its `canokeyU2fKeys` entry and SSH public key; `systemd-cryptenroll --wipe-slot=<n>`; remove it on each site | nothing, if a backup key or the passwords remain |
|
||||
| FIDO2 PIN forgotten or locked | Phone app: reset the WebAuthn application (needs the Admin PIN) | all passkeys, the SSH resident key, LUKS and sudo enrollments; redo section 2 |
|
||||
| OpenPGP PIN locked | `gpg --card-edit` → `admin` → `passwd`, unblock with the OpenPGP Admin PIN or Reset Code | nothing |
|
||||
| All OpenPGP PINs and Reset Code lost | Phone app: reset the OpenPGP application | on-card subkeys; re-import from the backup |
|
||||
| Admin PIN forgotten | Exhaust the Admin PIN, then in the app tap Reset and touch the key while the LED blinks, repeating until it stops | all user data; serial and attestation keys stay |
|
||||
|
||||
After any reset, rerun sections 1 and 2 for the affected applications.
|
||||
|
||||
## Enrollment status
|
||||
|
||||
| Key | Firmware | sudo | SSH | shoukei LUKS | OpenPGP | Browsers |
|
||||
| ------------------------ | -------- | ----------------- | ---------------------------------------------------------- | ----------------------------- | -------- | -------------------------------- |
|
||||
| CanoKey Canary (primary) | 3.0.3 | works on idols-ai | key created; public key not yet in `mainSshAuthorizedKeys` | enrolled; unlock not verified | deferred | WebAuthn works in Firefox/Chrome |
|
||||
|
||||
shoukei's first boots with the FIDO2 slot asked for the PIN, then fell back to the passphrase: USB
|
||||
only came up after switch-root, because on linux-asahi 7.2 its dwc3/PHY depend on the Thunderbolt
|
||||
(ACIO) nodes, whose `thunderbolt_apple` and `reset_apple_cio` drivers were missing from the initrd.
|
||||
nixos-apple-silicon added both upstream (`275e570ea8`), and the input now includes it; unlocking
|
||||
with the key is not yet verified. Also not verified: the CanoKey Admin PIN retry count, and how
|
||||
touch is performed when resetting over NFC.
|
||||
|
||||
## References
|
||||
|
||||
- [CanoKey user guide](https://docs.canokeys.org/userguide/): settings, WebAuthn, OpenPGP, PIV
|
||||
- [NixOS wiki: YubiKey](https://wiki.nixos.org/wiki/Yubikey): pam_u2f, `disable-ccid`
|
||||
- [pam-u2f](https://developers.yubico.com/pam-u2f/), `systemd-cryptenroll(1)`, `crypttab(5)`
|
||||
- Comparable NixOS configs: cloud-gouv/securix (`modules/pam/u2f.nix`), kclejeune/system,
|
||||
joshsymonds/nix-config, wimpysworld/nix-config
|
||||
Generated
+3
-3
@@ -598,11 +598,11 @@
|
||||
]
|
||||
},
|
||||
"locked": {
|
||||
"lastModified": 1792772387,
|
||||
"narHash": "sha256-MK6/UsOv1Ii71c+2U28GpmKn+Fm4MZG2TmIscuvUERw=",
|
||||
"lastModified": 1793626980,
|
||||
"narHash": "sha256-U98lLEsMqZUE9cp0gQTVlZdWSUBi+59OmwS7aB5txdo=",
|
||||
"owner": "nix-community",
|
||||
"repo": "nixos-apple-silicon",
|
||||
"rev": "46e80bc641f5aaee6ed7ef90a12314a81492f48f",
|
||||
"rev": "481cf53add16849ecd02c4419a1794ce70bfc0eb",
|
||||
"type": "github"
|
||||
},
|
||||
"original": {
|
||||
|
||||
+11
-14
@@ -18,12 +18,10 @@ workflow.
|
||||
browsers share an app-specific `/tmp` so external URLs reuse one browser instance.
|
||||
- Read-only `/nix/store`; GPU and display; fonts and themes; LAN and Internet.
|
||||
- Portals for file chooser, URI opening, notifications, input methods and document exports.
|
||||
- No whole host home, system D-Bus, SSH agent, raw USB/serial or raw camera. For
|
||||
Firefox/Chromium/Chrome, the only device passthrough is the FIDO HID interface of a security key:
|
||||
host udev rules hard-link FIDO-tagged hidraw nodes into `/dev/fido-hidraw`, which the sandbox
|
||||
binds together with read-only `/sys/class/hidraw` and the udev database, so keys can be plugged in
|
||||
after launch. Other HID interfaces, CCID and raw USB stay hidden. Raw PipeWire is granted only to
|
||||
MuseScore for its ALSA-via-PipeWire audio path; see [Limits](#limits).
|
||||
- No whole host home, system D-Bus, SSH agent, raw USB/serial or raw camera. The only device
|
||||
passthrough is a security key's FIDO interface for Firefox/Chromium/Chrome; see [Limits](#limits).
|
||||
Raw PipeWire is granted only to MuseScore for its ALSA-via-PipeWire audio path; see
|
||||
[Limits](#limits).
|
||||
- Host loopback only for Firefox/Chromium; all other apps use pasta-isolated loopback. Chromium is
|
||||
an intentional development exception. Brave Origin and Edge are backup browsers and receive no
|
||||
media grants.
|
||||
@@ -77,16 +75,15 @@ All browsers get read-only NSS certificates, printing, native notifications and
|
||||
- PulseAudio grants recording authority. Read-only GPG sockets still permit signing and decryption.
|
||||
- pasta isolates loopback, not LAN access. Chromecast discovery is unverified.
|
||||
- Brave Origin and Edge intentionally have no PulseAudio, Camera, ScreenCast or MPRIS grants. They
|
||||
are backup browsers, not media browsers. They also receive no FIDO2 passthrough.
|
||||
- FIDO2 passthrough is limited to the hidraw interface whose report descriptor declares the FIDO
|
||||
usage page. On the CanoKey that is the FIDO interface only: its KBD and CCID interfaces, other HID
|
||||
devices and raw USB stay outside the sandbox. A compromised browser process can send raw CTAP to
|
||||
the key; the key's PIN and touch policy remain the authentication boundary. The read-only udev
|
||||
are backup browsers, not media browsers.
|
||||
- FIDO2 passthrough: host udev rules hard-link only hidraw nodes whose report descriptor declares
|
||||
the FIDO usage page into `/dev/fido-hidraw`; the sandbox binds that directory plus read-only
|
||||
`/sys/class/hidraw` and the udev database. The CanoKey's KBD and CCID interfaces, other HID
|
||||
devices and raw USB stay outside, so the WebUSB console is unreachable by design
|
||||
([key policy](../docs/security-keys.md)). A compromised browser process can send raw CTAP to the
|
||||
key; the key's PIN and touch policy remain the authentication boundary. The read-only udev
|
||||
database exposes properties of all host devices, much of which is already readable via the sysfs
|
||||
device binds.
|
||||
- CanoKey management (CanoKey Console over WebUSB) is intentionally unavailable: Firefox has no
|
||||
WebUSB and the sandbox exposes no raw USB. PCs only use the key; management happens in the phone
|
||||
app. See [canokey.nix](../modules/nixos/desktop/canokey.nix) for the policy and its limits.
|
||||
- FIDO2 hotplug relies on udev events, which only reach the host network namespace. Firefox and
|
||||
Chromium therefore detect keys plugged in after launch; pasta-isolated Chrome needs the key
|
||||
present before launch. `/dev/fido-hidraw` is created at boot. When first deploying with `switch`
|
||||
|
||||
@@ -19,8 +19,7 @@ in
|
||||
# FIDO2 hotplug for sandboxed browsers (see modules/fido-bwrap.nix). The
|
||||
# directory is created at boot, before udevd starts, so the browser bind
|
||||
# succeeds even with no key present. NixOS applies /dev tmpfiles entries only
|
||||
# at boot; after a switch without reboot, run
|
||||
# `sudo systemd-tmpfiles --create --prefix=/dev/fido-hidraw` once.
|
||||
# at boot; for a first deploy via switch, see hardening/README.md (Limits).
|
||||
# Hard links share the device inode, so logind's uaccess ACLs stay
|
||||
# authoritative, and removal on unplug leaves no stale node for a reused
|
||||
# hidraw minor. 60-fido-id.rules sets ID_FIDO_TOKEN from the report
|
||||
|
||||
@@ -32,8 +32,8 @@ Currently I use both age & GnuPG:
|
||||
1. Age for secrets encryption(ssh key & other secret files), it's simple and easy to use.
|
||||
2. GnuPG for password-store and email encryption.
|
||||
|
||||
> At present, the safe and efficient use of GPG is probably combined with hardware keys such as
|
||||
> yubikey. but I don't have one, so I won't talk about it here.
|
||||
> Moving the subkeys onto a hardware key (CanoKey/YubiKey) is covered in
|
||||
> [hardware security keys](../../../../docs/security-keys.md#pass-openpgp).
|
||||
|
||||
## Practical Cryptography for Developers
|
||||
|
||||
|
||||
@@ -78,5 +78,8 @@
|
||||
# Specify how many times the passphrases mangling for symmetric encryption is repeated
|
||||
s2k-count = "65011712";
|
||||
};
|
||||
# Reach the CanoKey through pcscd instead of scdaemon's own CCID driver,
|
||||
# which would grab the USB interface exclusively (CanoKey OpenPGP FAQ).
|
||||
scdaemonSettings.disable-ccid = true;
|
||||
};
|
||||
}
|
||||
@@ -26,6 +26,10 @@ in
|
||||
{
|
||||
home.file.".ssh/romantic.pub".source = "${mysecrets}/public/romantic.pub";
|
||||
|
||||
# One SSH key for GitHub and every host lives on the CanoKey as a resident
|
||||
# FIDO2 credential, exported on each desktop to ~/.ssh/id_ed25519_sk (ssh's
|
||||
# default identity); every use needs a touch. The per-host keys stay
|
||||
# authorized as the backup. Setup: docs/security-keys.md.
|
||||
programs.ssh = {
|
||||
enable = true;
|
||||
|
||||
|
||||
@@ -11,7 +11,11 @@ in
|
||||
|
||||
modules.desktop.vinput.enable = true;
|
||||
|
||||
programs.ssh.settings."github.com".IdentityFile = "${config.home.homeDirectory}/.ssh/${hostName}";
|
||||
# CanoKey key first (docs/security-keys.md), this host's key as backup.
|
||||
programs.ssh.settings."github.com".IdentityFile = [
|
||||
"${config.home.homeDirectory}/.ssh/id_ed25519_sk"
|
||||
"${config.home.homeDirectory}/.ssh/${hostName}"
|
||||
];
|
||||
|
||||
modules.desktop.gaming.enable = false;
|
||||
modules.desktop.niri.enable = true;
|
||||
|
||||
@@ -12,7 +12,11 @@ in
|
||||
|
||||
modules.desktop.vinput.enable = true;
|
||||
|
||||
programs.ssh.settings."github.com".IdentityFile = "${config.home.homeDirectory}/.ssh/idols-ai";
|
||||
# CanoKey key first (docs/security-keys.md), this host's key as backup.
|
||||
programs.ssh.settings."github.com".IdentityFile = [
|
||||
"${config.home.homeDirectory}/.ssh/id_ed25519_sk"
|
||||
"${config.home.homeDirectory}/.ssh/idols-ai"
|
||||
];
|
||||
|
||||
modules.desktop.gaming.enable = true;
|
||||
modules.desktop.niri.enable = true;
|
||||
|
||||
@@ -53,6 +53,13 @@ in
|
||||
# Enabling this should improve performance on SSDs;
|
||||
# https://wiki.archlinux.org/index.php/Dm-crypt/Specialties#Disable_workqueue_for_increased_solid_state_drive_(SSD)_performance
|
||||
bypassWorkqueues = true;
|
||||
# Unlock with the CanoKey (FIDO2 PIN + touch); the passphrase slot stays.
|
||||
# Without the key, the passphrase prompt appears after token-timeout.
|
||||
# Enroll before deploying: docs/security-keys.md.
|
||||
crypttabExtraOpts = [
|
||||
"fido2-device=auto"
|
||||
"token-timeout=10s"
|
||||
];
|
||||
};
|
||||
};
|
||||
|
||||
|
||||
@@ -2,6 +2,7 @@
|
||||
pkgs,
|
||||
config,
|
||||
lib,
|
||||
myvars,
|
||||
...
|
||||
}:
|
||||
let
|
||||
@@ -12,26 +13,31 @@ in
|
||||
enable = lib.mkEnableOption "CanoKey hardware security key support";
|
||||
};
|
||||
|
||||
# CanoKey docs: https://docs.canokeys.org/userguide/
|
||||
#
|
||||
# Principle: management and use happen on different devices. Linux PCs only
|
||||
# use the key (WebAuthn/passkeys, OpenPGP, SSH). CanoKey Console management
|
||||
# (Admin PIN, application/factory reset, device settings) happens only in the
|
||||
# phone app (https://docs.canokeys.org/userguide/admin/), so the Admin PIN is
|
||||
# never typed on a PC.
|
||||
#
|
||||
# Sandboxed browsers back this up: they see only the FIDO HID interface
|
||||
# (hardening/nixpaks), not raw USB or CCID, so the WebUSB console cannot reach
|
||||
# the key, and the vendor's WebUSB udev rule (MODE 0666 on the raw USB node)
|
||||
# is deliberately not installed. Unsandboxed software is trusted; if it is
|
||||
# malicious, the PC is compromised regardless.
|
||||
# Usage policy, setup, backup keys and recovery: docs/security-keys.md.
|
||||
# PCs only use the key and the phone app manages it, so the vendor's WebUSB
|
||||
# udev rule (MODE 0666 on the raw USB node) is deliberately not installed.
|
||||
config = lib.mkIf cfg.enable {
|
||||
# systemd tags FIDO/CCID devices uaccess (60-fido-id.rules); pcscd covers OpenPGP.
|
||||
services.pcscd.enable = true;
|
||||
|
||||
# sudo accepts a key touch instead of the password; without the key it asks
|
||||
# for the password as before. Login keeps the password, which also unlocks
|
||||
# GNOME Keyring. sudo is unchanged until myvars.canokeyU2fKeys has an entry
|
||||
# (registration: docs/security-keys.md).
|
||||
security.pam.u2f.settings = {
|
||||
authfile = pkgs.writeText "u2f-keys" ''
|
||||
${myvars.username}:${lib.concatMapStringsSep ":" (lib.removePrefix ":") myvars.canokeyU2fKeys}
|
||||
'';
|
||||
# Shared by all hosts, so one registration works on idols-ai and shoukei.
|
||||
origin = "pam://ryan4yin";
|
||||
cue = true;
|
||||
};
|
||||
security.pam.services.sudo.u2f.enable = myvars.canokeyU2fKeys != [ ];
|
||||
|
||||
environment.systemPackages = with pkgs; [
|
||||
ccid
|
||||
pcsc-tools
|
||||
pam_u2f # pamu2fcfg
|
||||
];
|
||||
};
|
||||
}
|
||||
@@ -29,6 +29,12 @@
|
||||
"ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIJwoI5MAogEa726jwwHL5EgM1X/i2A5d2pgV7i7t8fzB ryan@shoukei"
|
||||
"ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIDc1PNTXzzvd93E+e9LXvnEzqgUI5gMTEF/IitvzgmL+ ryan@frieren"
|
||||
];
|
||||
# CanoKey U2F registrations for sudo (modules/nixos/desktop/canokey.nix).
|
||||
# Key handles and public keys only, so they are safe to commit.
|
||||
canokeyU2fKeys = [
|
||||
# CanoKey Canary (primary)
|
||||
"DwXDxVU+NDTUZs/d2EjpsPAh4mrg7dqdg/mAozkw/mUAAdEYDZIbm8kTBUGA49wXW0ZvSpF9VNYh2w84Xz9nAIAW////+Q==,6hqEjWBJ+ueBKBJaNijNkUsmlgEHMgv0KdpprqdJjHKoU/FKpeqo12SWlvdgiIVWvqTaGfe4fNu/ckcGY5mlsA==,es256,+presence"
|
||||
];
|
||||
secondaryAuthorizedKeys = [
|
||||
# the backup ssh keys for disaster recovery
|
||||
"ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIMzYT0Fpcp681eHY5FJV2G8Mve53iX3hMOLGbVvfL+TF ryan@romantic"
|
||||
|
||||
Reference in new issue
Block a user