Native Secure Enclave backed SSH keys on macOS

📝 Discussion Summary (Click to expand)

The Hacker News discussion revolves around the use of hardware-backed keys (specifically macOS Secure Enclave integration) for SSH and GPG, often in comparison to other security methods like YubiKeys or traditional passphrases.

Here are the three most prevalent themes:

1. Debate Over the Security and Practicality of Backing Up Software-Protected Keys

A significant portion of the discussion focuses on whether private keys stored in the Secure Enclave (SE) should be exportable, and how this contrasts with the desire for backups versus the security principle of non-exportability. Users who prioritize operational continuity argue for exportability for disaster recovery, while others insist that allowing export negates the primary security benefit of the SE.

Supporting Quote (Concern over exportability): "If I understand correctly, this means you can't back up the private key, correct? It's in the Secure Enclave, so if you lose your laptop, you also lose the key?" asked user "jedberg".
Supporting Quote (Counterargument): "The advantage of non-exportable, HSM-backed keys is that you are guaranteed that the only way to use that key is to have online access to the HSM, and you can recover from HSM access compromise without having to replace the keys," argued user "Nextgrid".

2. Preference for Native/Built-in Solutions Over Third-Party Tools

There is clear enthusiasm for Apple's native integration of SSH key management with the Secure Enclave (using tools like sc_auth), viewing it as superior to relying on third-party software that requires installation and adds complexity or friction.

Supporting Quote (Native vs. Third-Party): User "traceroute66" stated the new method is better because "Secretive required installation, which is both friction and security-sensitive tool written by a third party. This is native, written by Apple, available out-of-the-box in Tahoe."
Supporting Quote (Convenience): User "cedws" noted, "Secretive is a bit friendlier to set up but I'll probably switch to this anyway so I have one less app on my computer."

3. Key Management Strategy: Per-Device vs. Portable Keys (SSH Certificates as a Solution)

Users diverge on the best structural approach for managing SSH keys, specifically whether to use separate keys for every device (making backups difficult) or a single, centralized key/identity. SSH Certificate Authorities (CAs) are frequently brought up as the preferred method to handle infrastructure scalability shortcomings associated with managing many individual public keys across many servers.

Supporting Quote (Challenge of multiple keys): User "morshu9001" lamented the process of securing new devices: "If you get a new device, you have to go add its pubkey to every server you ever use... it was way easier to just copy .ssh onto it rather than hunting everything down."
Supporting Quote (SSH CA solution): User "yjftsjthsd-h" suggested a scalable alternative: "There is an easier way: Create a SSH CA, add that to your authorized_keys everywhere, use it to sign the individual public keys."

🚀 Project Ideas

Secure Enclave Key Activity Listener (SE-KAL)

Summary

A lightweight monitoring service for macOS that registers for authentication events originating from the Secure Enclave (like SSH key usage or GPG signing) and provides transparent, low-friction user notifications without blocking the operation.
Solves the usability friction of repeated, mandatory biometrics required for frequent operations (like Git commits) when using Secure Enclave-backed keys, by providing passive confirmation instead of active gatekeeping.

Details

Key	Value
Target Audience	Mac users adopting native SE-backed SSH/GPG keys who find constant TouchID prompts disruptive for high-frequency tasks (e.g., Git commits, `ssh-agent` usage).
Core Feature	Daemon that listens to system-level Secure Enclave usage logs or utilizes CryptoTokenKit callbacks to detect private key operations, triggering local (non-blocking) notifications (e.g., via Notification Center or a simple status bar indicator).
Tech Stack	Swift/Objective-C for native macOS daemon, leveraging CryptoTokenKit (CTK) or related entitlements/APIs for Secure Enclave event monitoring.
Difficulty	Medium (Accessing secure event logs/hooks might require specific entitlements or kernel extensions, though passive monitoring should be easier than interception).
Monetization	Hobby

Notes

Why HN commenters would love it (quote users if possible): Responds directly to n0ot: "The one thing holding me back is that I like that Secretive allows you to create keys that don't require TouchID, yet still notifies you when they are used... I'd at least like to know when my git signing key is being used."
Potential for discussion or practical utility: Enables users to leverage the highest security (non-exportable SE keys) while mitigating the primary usability complaint (constant biometric requirement for high-frequency tasks).

Exportable Secure Enclave Key Management Utility (SE-Migrator)

Summary

A command-line tool that facilitates secure, one-time migration of a non-exportable Secure Enclave SSH key to a new device or a true offline backup (like a YubiKey). It automates the process involving TouchID prompts for key export/re-enrollment, which currently requires multiple complex manual steps.
Addresses the operational requirements of replacing or backing up devices, which commenters noted is a major gap compared to traditional key management.

Details

Key	Value
Target Audience	Power users, sysadmins, and individuals frequently upgrading hardware or needing robust disaster recovery plans for their primary identity keys locked in the Secure Enclave.
Core Feature	Wrapper around `sc_auth` to securely trigger the exportable key creation path, handling the TouchID challenge once, encrypting the resulting artifact with a user-provided passphrase, and optionally providing utility functions to re-import or wipe the local reference.
Tech Stack	Swift/Shell script leveraging existing `sc_auth` CLI functions, utilizing `openssl` or symmetric encryption libraries (ChaCha20 recommended) for the final migration bundle encryption.
Difficulty	Medium/High (Requires careful handling of the export flow and robust error handling if Apple's underlying CLI changes.)
Monetization	Hobby

Notes

Why HN commenters would love it (quote users if possible): Solves the "hole" identified by jedberg: "If I understand correctly, this means you can't back up the private key, correct? It's in the Secure Enclave, so if you lose your laptop, you also lose the key?" This tool provides a controlled pathway for that backup via the user's own discretion.
Potential for discussion or practical utility: Spurs debate on the philosophical utility of exportable vs. non-exportable keys, while providing a practical bridge for users who must manage key lifecycle across devices.

Cross-Platform SSH Key Status Monitor (KeyStatusHub)

Summary

A cross-platform (macOS/Linux/Windows) desktop application that abstracts the differences in hardware-backed key management (SE, TPM, YubiKey) into a unified UI, checking the operational status and distribution of the primary SSH public key.
Simplifies the complexity developers face when managing keys across multiple hardware contexts and ensures the public key is present where needed.

Details

Key	Value
Target Audience	Developers who use a mix of macOS (SE), Linux (TPM via `ssh-tpm-agent`), and/or YubiKeys, and struggle with key distribution across heterogeneous servers.
Core Feature	Connects via SSH or configuration file inspection (where available) to a defined list of servers/Git hosts, cross-referencing the local active public key ID against the remote `authorized_keys` or server trust list, flagging missing or mismatched keys.
Tech Stack	Electron/Tauri (for cross-platform desktop UI), focused on simple remote connectivity (SSH/API calls) and integrating platform-specific commands (`ssh-add -l`, reading SE identity status via helper CLI, querying TPM agent status).
Difficulty	High (Requires writing/integrating platform-specific drivers for SE, TPM, and YubiKey status retrieval, while maintaining server connection logic.)
Monetization	Hobby

Notes

Why HN commenters would love it (quote users if possible): Addresses the operational pain points expressed by morshu9001: "when I got a new laptop, it was way easier to just copy .ssh onto it rather than hunting everything down." and QuantumNomad_: "...if you have very many servers you’d probably want to use a configuration management tool...". This acts as a personal, lightweight CM for public key distribution status.
Potential for discussion or practical utility: It turns key management from a system-level headache into a desktop application dashboard, appealing to the HN preference for visibility and control over complex infrastructure.