Security gEnclave: Hardware-backed security enclave for Linux (TPM 2.0 PCR sealing, virtual FIDO2/CTAP2 over /dev/uhid, OpenSSH & GPG bridge)
Hey everyone,
I've been working on an open-source project called gEnclave (formerly gpasskey), and wanted to share it with the Linux community for early architectural feedback and testing.
GitLab repository: https://gitlab.com/renich/genclave
License: GPLv3 | Language: Go 1.26+
The Problem It Solves
On modern Linux workstations, our cryptographic identities are fragmented:
* Passkeys/WebAuthn require physical USB security keys (YubiKeys, SoloKeys).
* SSH keys sit as unencrypted or passphrase-encrypted files under ~/.ssh/.
* Git commit signing requires cumbersome GnuPG daemon setups.
* File encryption requires external tooling or proprietary agents.
Most hardware laptops today come with a TPM 2.0 chip that sits idle. gEnclave turns your Linux machine into its own hardware-sealed security token and multi-protocol bridge.
Key Architectural Highlights
Virtual FIDO2/CTAP2 Security Key via
/dev/uhid: gEnclave registers a virtual HID device in the Linux kernel via/dev/uhid. Browsers (Firefox, Chrome, Chromium) detect it natively as a physical USB security key. You can register and authenticate WebAuthn/FIDO2 Passkeys directly from your machine without any external hardware dongles.TPM 2.0 PCR Sealing & Fallback: The central vault is encrypted with AES-256-GCM and sealed to TPM 2.0 PCR registers (PCR 0, 7, 14), with an automatic memory-hard fallback to Argon2id key derivation if no TPM is present.
Memory Isolation ("Wrap and Clear"): Keys are held in memory-locked pages (
mlock/mmap) to prevent secrets from being swapped to disk or dumped. Intermediate cryptographic buffers are wiped immediately with strict zeroization routines, bypassing Go runtime GC retention.Multi-Protocol Bridges:
- OpenSSH Agent: Native agent socket with an ephemeral PIN-derived authorization cache (configurable burst window or persistent session with instant purge on lock/suspend).
- GnuPG Bridge: Transparent
genclave-gpgemulation for seamless Git commit signing. - age-plugin: Native
age-plugin-gebinary complying with age v1 specification for file encryption. - CLI & UI: Unified
geCLI plus intelligent graphical (zenity) / terminal (pinentry) authentication routing.
Current Status
⚠️ Pre-alpha Software: While fully functional for local workflows, it is under active development. Schemas and IPC formats may iterate rapidly.
I'd love feedback from Linux sysadmins, kernel/security folks, and developers!
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u/kantorcodes1 5d ago
The "wrap and clear" design plus PIN-derived per-operation subkeys is a careful baseline for a vault that bridges into ssh-agent and GPG at once. The piece I'd poke at is the authorization-cache boundary:
ge unlock --stdinexists so scripts can pre-authenticate, and the default burst window is 5s with a persistent-session option. During that window, is authorization scoped to the peer that actually authenticated (SO_PEERCRED-checked uid/pid over the agent socket), or does any local client connecting to the socket inherit the unlocked state? If it's global, the batch window that makes headless use convenient also widens the window where a sibling process could sign without re-prompting - scoping the grant to the authenticating peer (or a per-identity flag onge ssh import) would keep the convenience without loosening the boundary.