⚠️ Installers live on Cloudflare R2 (download-osh.moninotes.com) · iOS TestFlight link pending Beta Review approval
Zero-Trust SSH

Log in to servers
with no passwords.

Short-lived SSH certificates — requested by your laptop, approved on your iPhone, signed by a YubiKey-backed CA. Nothing static to steal.

zero-trust-flow
[ OSH Approver · iPhone ] [ CA Signer · YubiKey ] │ approve (Face ID) │ sign cert (PIV 9c) ▼ ▼ [ OSH Client ] ──▶ [ Gateway ] ──────────────┘ │ request cert │ issue short-lived cert └──────────────────┴──────────▶ [ Target server ] # TrustedUserCAKey

Download

Pick your role in the system

macOS builds are signed & notarized — open them directly. Always download through a browser to keep the signature intact.

Gateway Available

Server (Linux) — the broker that issues certs

Ubuntu / Debian · amd64 .deb Download
Ubuntu / Debian · arm64 .deb Download
RHEL / Rocky · x86_64 .rpm Download
RHEL / Rocky · aarch64 .rpm Download

OSH Approver Pending review

iOS — approves & signs requests (Secure Enclave + Face ID)

iPhone · TestFlight TestFlight

Public build is pending Beta App Review (~24–48h). Until then, invite testers via Internal (send your Apple ID).

CA Signer Cross-platform

Signs certificates with a YubiKey (PIV slot 9c)

macOS · Apple Silicon .dmg Download
Windows .exe Download
Ubuntu · amd64 .deb Download

OSH Client Cross-platform

Workstation — where you run ssh to get a cert

macOS · Apple Silicon .pkg · GUI + CLI Download
Windows .exe Download
Ubuntu · amd64 .deb Download

OSH CLI Terminal

Just the osh command — servers / headless / scripts (no GUI)

Ubuntu/Debian · amd64 .deb Download
Ubuntu/Debian · arm64 .deb Download
RHEL/Rocky · x86_64 .rpm Download
RHEL/Rocky · aarch64 .rpm Download
Windows · x64 .zip Download

macOS: osh is already inside the OSH Client .pkg above.

Install

Get running in a few steps

Four pieces on four machines. The Gateway is a Linux server (the broker); the OSH Client, CA Signer & iPhone Approver are cross-platform — see the apps block below. Copy-paste per platform.

gateway — linux server
# 1) Download the .deb / .rpm above (your OS + arch), then install it sudo apt install ./pam-zta-gateway_0.1.0_amd64.deb # Ubuntu / Debian sudo yum install ./pam-zta-gateway-0.1.0-1.x86_64.rpm # RHEL / Rocky / Fedora (dnf works too) # 2) Point it at SQLite (no PostgreSQL) + set a CA token — edit /etc/pam-zta/gateway.toml: # [database] driver = "sqlite" path = "/var/lib/pam-zta/gateway.db" # [ca] token = "PASTE" # openssl rand -hex 32 — hand this token to the CA operator sudo systemctl enable --now pam-zta-gateway sudo journalctl -u pam-zta-gateway -f # watch for the root-enroll QR # 3) Connect to this gateway: # OSH client → http://SERVER:8443 (osh --gateway http://SERVER:8443) # CA Signer → ws://SERVER:8443/v1/ca/ws + the [ca].token you set above # HA / multi-node? Use PostgreSQL instead of SQLite ([database] host/user/... ).
desktop & ios — apps
# macOS — CA Signer (.dmg) Open the .dmg ▸ drag "PAM-ZTA CA" to Applications ▸ open ▸ plug YubiKey ▸ enter PIN (PIV 9c) ▸ "Save PIN to Keychain". # macOS — OSH Client (.pkg · all-in-one: GUI app + `osh` command) Double-click OSH-1.1.0-arm64.pkg ▸ Install. # notarized · installs the OSH app + the `osh` CLI into PATH osh connect dev@your-server # or open the OSH app and click Connect · (new terminal: run `rehash`) # Windows — CA Signer / OSH Client (.exe · not yet code-signed) Run the .exe ▸ on SmartScreen "Windows protected your PC" ▸ More info ▸ Run anyway. # Ubuntu/Debian — CA Signer / OSH Client (.deb · amd64) sudo apt install ./CA-0.1.0-amd64.deb # CA Signer (Operator Console) sudo apt install ./OSH-0.1.0-amd64.deb # OSH Client # iOS (OSH Approver) 1. Install TestFlight from the App Store. 2. Open the TestFlight link above ▸ Install OSH. 3. Open OSH ▸ scan the enrollment QR from the Gateway ▸ approve with Face ID.
using osh — enroll once, then connect
# 1) First time on a gateway: point osh at it, then enroll this device (an admin approves it once). export OSH_GATEWAY=https://your-gateway:8443 # add to ~/.bashrc → skip --gateway every time osh enroll --force # registers this device · an admin approves it in the App Signer osh status # optional: expect status:ok, ca_connected:true # 2) Log in — ONE command. The login user must MATCH an access rule (e.g. root — not just any name): osh root@10.0.0.5 # short for: osh connect root@10.0.0.5 # • osh asks the Gateway for a certificate for root@10.0.0.5 # • your iPhone buzzes → review who / where / what → Approve with Face ID # • the CA (YubiKey) signs a short-lived cert → you land in the SSH session ✅ # (session recorded to ~/.osh/sessions/ · cert expires in minutes · nothing static left behind) # Rejected? 401 = device not enrolled on THIS gateway → re-run osh enroll --force # 403 = device not approved yet, or the login user doesn't match a rule
🔐CA Signer requires a YubiKey (hardware-only, fail-closed). Pull the YubiKey and signing stops — exactly by zero-trust design.