JWK sets (#809)

Co-authored-by: Luke Curley <kixelated@gmail.com>

Author: einrobin

Cargo.lock

@@ -0,0 +1,133 @@
+---
+title: moq-authentication
+description: Authentication for the moq-relay
+---
+
+# MoQ authentication
+
+The MoQ Relay authenticates via JWT-based tokens. Generally there are two different approaches you can choose from:
+- asymmetric keys: using a public and private key to separate signing and verifying keys for more security
+- symmetric key: using a single secret key for signing and verifying, less secure
+
+## Symmetric key
+
+1. Generate a secret key:
+```bash
+moq-token --key root.jwk generate --algorithm HS256
+```
+:::details You can also choose a different algorithm
+- HS256
+- HS384
+- HS512
+:::
+
+2. Configure relay:
+:::code-group
+```toml [relay.toml]
+[auth]
+# public = "anon"     # Optional: allow anonymous access to anon/**
+key = "root.jwk"    # JWT key for authenticated paths
+```
+:::
+
+3. Generate tokens:
+```bash
+moq-token --key root.jwk sign \
+  --root "rooms/123" \
+  --publish "alice" \
+  --subscribe "" \
+  --expires 1735689600 > alice.jwt
+```
+
+## Asymmetric keys
+
+Generally asymmetric keys can be more secure because you don't need to distribute the signing key to every relay instance, the relays only need to verifying (public) key.
+
+1. Generate a public and private key:
+```bash
+moq-token --key private.jwk generate --public public.jwk --algorithm RS256
+```
+:::details You can also choose a different algorithm
+- RS256
+- RS384
+- RS512
+- PS256
+- PS384
+- PS512
+- EC256
+- EC384
+- EdDSA
+:::
+
+2. Now the relay only requires the public key:
+:::code-group
+```toml [relay.toml]
+[auth]
+# public = "anon"     # Optional: allow anonymous access to anon/**
+key = "public.jwk"    # JWT key for authenticated paths
+```
+:::
+
+3. Generate tokens using the private key:
+```bash
+moq-token --key private.jwk sign \
+  --root "rooms/123" \
+  --publish "alice" \
+  --subscribe "" \
+  --expires 1735689600 > alice.jwt
+```
+
+## JWK set authentication
+
+Instead of storing a public key locally in a file, it may also be retrieved from a server hosting a JWK set. This can be a simple static site serving a JSON file, or a fully OIDC compliant Identity Provider. That way you can easily implement automatic key rotation.
+
+::: info
+This approach only works with asymmetric authentication.
+:::
+
+To set this up, you need to have an HTTPS server hosting a JWK set that looks like this:
+```json
+{
+  "keys": [
+    {
+      "kid": "2026-01-01",
+      "alg": "RS256",
+      "key_ops": [
+        "verify"
+      ],
+      "kty": "RSA",
+      "n": "zMsjX1oDV2SMQKZFTx4_qCaD3iIek9s1lvVaymr8bEGzO4pe6syCwBwLmFwaixRv7MMsuZ0nIpoR3Slpo-ZVyRxOc8yc3DcBZx49S_UQcM76E4MYbH6oInrEP8QL2bsstHrYTqTyPPjGwQJVp_sZdkjKlF5N-v5ohpn36sI8PXELvfRY3O3bad-RmSZ8ZOG8CYnJvMj_g2lYtGMMThnddnJ49560ahUNqAbH6ru---sHtdYHcjTIaWX4HYP6Y_KjA6siDZTGTThpaEW45LKcDQWM9sYvx_eAstaC-1rz8Z_6fDgKFWr7qcP5U2NmJ0c-IGSu_8OkftgRH4--Z5mzBQ",
+      "e": "AQAB"
+    },
+    {
+      "kid": "2025-12-01",
+      "alg": "EdDSA",
+      "key_ops": [
+        "verify"
+      ],
+      "kty": "OKP",
+      "crv": "Ed25519",
+      "x": "2FSK2q_o_d5ernBmNQLNMFxiA4-ypBSa4LsN30ZjUeU"
+    }
+  ]
+}
+```
+
+:::tip The following must be considered:
+- Every JWK MUST be public and contain no private key information
+- If your JWK set contains more than one key:
+  1. Every JWK MUST have a `kid` so they can be identified on verification
+  2. Your JWT tokens MUST contain a `kid` in their header
+  3. `kid` can be an arbitrary string
+:::
+
+Configure the relay:
+:::code-group
+```toml [relay.toml]
+[auth]
+# public = "anon"                                               # Optional: allow anonymous access to anon/**
+
+key = "https://auth.example.com/keys.json"                      # JWK set URL for authenticated paths
+refresh_interval = 86400                                   # Optional: refresh the JWK set every N seconds, no refreshing if omitted
+```
+:::

doc/guide/authentication.md

@@ -30,7 +30,7 @@ futures = "0.3"
 http-body = "1"
 moq-lite = { workspace = true, features = ["serde"] }
 moq-native = { workspace = true, features = ["aws-lc-rs"] }
-moq-token = { workspace = true }
+moq-token = { workspace = true, features = ["jwks-loader"] }
 rustls = { version = "0.23", features = [
 	"aws-lc-rs",
 ], default-features = false }