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2026-09-29 14:21:04 +02:00 · 2026-09-29 14:21:04 +02:00 · ce8bdcf09d
parent 591bbc701e
commit ce8bdcf09d
12 changed files with 3448 additions and 38 deletions
--- a/.gitignore
+++ b/.gitignore
@ -1 +1,2 @@
-/target
+target/
+/data
--- a/Cargo.lock
+++ b/Cargo.lock
--- a/Cargo.toml
+++ b/Cargo.toml
@ -4,9 +4,21 @@ version = "0.1.0"
 edition = "2024"

 [dependencies]
+axum = { version = "0.8", features = ["ws"] }
+axum-server = { version = "0.8", default-features = false, features = ["tls-rustls-no-provider"] }
+base64 = "0.22"
+clap = { version = "4.6.7", features = ["derive", "env"] }
 extism = { version = "1.30", default-features = false, features = ["wasmtime-default-features"] }
+rcgen = { version = "0.14", features = ["x509-parser"] }
+reqwest = { version = "0.13", default-features = false, features = ["rustls-no-provider"] }
+ring = "0.17"
+rusqlite = { version = "0.40", features = ["bundled"] }
+rustls = { version = "0.23", default-features = false, features = ["ring", "std", "tls12"] }
 serde = { version = "1", features = ["derive"] }
 serde_json = "1"
+tokio = { version = "1", features = ["full"] }
+uuid = { version = "1", features = ["v4"] }

 [dev-dependencies]
+tempfile = "3"
 wat = "1"
--- a/README.md
+++ b/README.md
@ -0,0 +1,161 @@
+# Wolloseum
+
+Wolloseum is a deterministic, procedurally generated game server. Players
+upload untrusted WASM agents (run in a sandboxed Extism/Wasmtime runtime with
+fuel and memory limits) that control spawned agents in a tick-based
+simulation. All identity and request authentication is certificate-based
+(Ed25519 client certificates signed by a locally issued root CA); there are no
+passwords or bearer tokens.
+
+## Building the server
+
+```sh
+cargo build --release
+```
+
+The binary is produced at `target/release/wolloseum`.
+
+## Configuration
+
+The server takes its configuration from CLI flags (each with an environment
+variable fallback), defined in [src/cli.rs](src/cli.rs):
+
+| Flag         | Env var              | Default          | Purpose                                            |
+| ------------ | -------------------- | ---------------- | -------------------------------------------------- |
+| `--data-dir` | `WOLLOSEUM_DATA_DIR` | `data`           | Directory for certificates and the SQLite database |
+| `--bind`     | `WOLLOSEUM_BIND`     | `127.0.0.1:8080` | HTTP listener address                              |
+
+On first start the server bootstraps a PKI under `<data-dir>/certificates/`:
+
+- `root-ca.pem` / `root-ca-key.pem` — self-signed root CA
+- `server.pem` / `server-key.pem` — HTTP server certificate (issued for `localhost`)
+- `admin-client.pem` / `admin-client-key.pem` — the initial admin client identity
+
+The SQLite database is created at `<data-dir>/wolloseum.sqlite3` and stores
+identities, used request nonces, per-player agent WASM, and the core
+simulation WASM module. Private key files and the certificate directory are
+written with restrictive (owner-only) permissions on Unix.
+
+## Running the server
+
+```sh
+cargo run --release -- serve --data-dir data --bind 127.0.0.1:8080
+```
+
+On startup the server prints the admin certificate ID and the paths to the
+admin client certificate/key and root CA certificate — you'll need these to
+issue authenticated CLI/API requests.
+
+## API endpoints
+
+All `/api/*` endpoints except `/api/status` and `/api/events` require request
+signing. Each signed request must include:
+
+```
+X-Client-Id:          <sha256 hex of the client's certificate PEM>
+X-Request-Timestamp:  <unix seconds, within 60s of server time>
+X-Request-Nonce:      <unique, ASCII alphanumeric/-/_, replay-checked>
+X-Request-Signature:  <base64 Ed25519 signature>
+```
+
+The signed message is `METHOD\nPATH\nTIMESTAMP\nNONCE\n` followed by the raw
+request body bytes.
+
+| Method | Path                | Auth                | Description                                                 |
+| ------ | ------------------- | ------------------- | ----------------------------------------------------------- |
+| GET    | `/`                 | none                | Player web UI                                               |
+| GET    | `/admin`            | none                | Admin web UI                                                |
+| GET    | `/api/status`       | none                | Current game running state                                  |
+| GET    | `/api/events`       | none (WebSocket)    | Live game/agent/core state change events                    |
+| POST   | `/api/create_user`  | admin               | Create a player identity, returns certificate + private key |
+| POST   | `/api/delete_user`  | admin               | Delete a player identity and their uploaded agent           |
+| POST   | `/api/start_game`   | admin               | Resume the simulation                                       |
+| POST   | `/api/stop_game`    | admin               | Pause the simulation                                        |
+| POST   | `/api/update_agent` | any active identity | Upload/replace the caller's agent WASM module               |
+| POST   | `/api/upload_core`  | admin               | Upload/replace the core simulation WASM module              |
+
+### `/api/upload_core`
+
+Replaces the core simulation logic module. The request body is the raw WASM
+bytes (not JSON), following the same conventions as `/api/update_agent`:
+
+- Body limit: 1 MiB (`Content-Length` over the limit is rejected)
+- The module is sandboxed-loaded (no WASI imports, bounded memory) to confirm
+  it is valid before being persisted
+- Requires admin authentication (signed request headers as above)
+- On success the module is stored in the `core_module` table (single active
+  row) and a `core_uploaded` event is published over `/api/events`
+
+```sh
+curl -k http://127.0.0.1:8080/api/upload_core \
+  -X POST \
+  --data-binary @core_simulation.wasm \
+  -H "x-client-id: $ADMIN_ID" \
+  -H "x-request-timestamp: $TS" \
+  -H "x-request-nonce: $NONCE" \
+  -H "x-request-signature: $SIGNATURE"
+```
+
+In practice, use the CLI (below) rather than constructing signatures by hand.
+
+## Using the CLI client
+
+The same binary provides a signing HTTP client:
+
+```sh
+cargo run --release -- cli \
+  --server http://127.0.0.1:84080\
+  --root-ca data/certificates/root-ca.pem \
+  --client-cert data/certificates/admin-client.pem \
+  --client-key data/certificates/admin-client-key.pem \
+  status
+```
+
+Available subcommands (see [src/cli.rs](src/cli.rs)): `status`,
+`create-user <username>`, `delete-user <client_id>`, `stop-game`,
+`start-game`, `update-agent <path>`.
+
+## Building the example WASM agent
+
+[example-wasm-agent/](example-wasm-agent) is a standalone crate implementing
+a minimal Extism plugin agent matching the ABI expected by
+[src/wasm_agent.rs](src/wasm_agent.rs) (a JSON `decide` call taking
+`{abi_version, tick, x, y, adjacent_terrain}` and returning
+`{abi_version, action}`). Movement is a deterministic function of the tick
+and position — no RNG, clock, or host access is used, so replays are
+reproducible.
+
+Build it to a `.wasm` file:
+
+```sh
+cd example-wasm-agent
+rustup target add wasm32-unknown-unknown # if not already installed
+cargo build --release --target wasm32-unknown-unknown
+```
+
+The compiled module is at
+`example-wasm-agent/target/wasm32-unknown-unknown/release/example_wasm_agent.wasm`.
+
+## Uploading the example agent
+
+First create a player identity (as admin), then upload the agent WASM signed
+with that player's own certificate:
+
+```sh
+# As admin, create a player and save the returned certificate/private key:
+cargo run --release -- cli \
+  --client-cert data/certificates/admin-client.pem \
+  --client-key data/certificates/admin-client-key.pem \
+  create-user alice
+# -> write the returned certificate_pem/private_key_pem to alice.pem / alice-key.pem
+
+# As alice, upload the compiled agent:
+cargo run --release -- cli \
+  --client-cert alice.pem \
+  --client-key alice-key.pem \
+  update-agent example-wasm-agent/target/wasm32-unknown-unknown/release/example_wasm_agent.wasm
+```
+
+Core simulation WASM can be uploaded the same way by an admin using
+`POST /api/upload_core` (no dedicated CLI subcommand yet — use `curl` as shown
+above, or extend the CLI client following the same pattern as `update-agent`).
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+
+[dependencies]
+extism-pdk = "1"
+serde = { version = "1", features = ["derive"] }
+
+[profile.release]
+opt-level = "z"
+lto = true
+codegen-units = 1
+panic = "abort"
+strip = true
--- a/example-wasm-agent/src/lib.rs
+++ b/example-wasm-agent/src/lib.rs
@ -0,0 +1,65 @@
+use extism_pdk::*;
+use serde::{Deserialize, Serialize};
+
+const ABI_VERSION: u16 = 1;
+const BOUNDARY_TERRAIN: i32 = 3;
+
+#[derive(Deserialize)]
+struct DecisionInput {
+    #[allow(dead_code)]
+    abi_version: u16,
+    tick: u64,
+    x: u16,
+    y: u16,
+    adjacent_terrain: [i32; 4],
+}
+
+#[derive(Serialize)]
+struct DecisionOutput {
+    abi_version: u16,
+    action: i32,
+}
+
+/// Deterministic decision function called once per simulation tick.
+///
+/// The host provides the full observation as JSON input and expects a JSON
+/// decision back; no filesystem, network, clock, or RNG access is available.
+/// Movement here is a reproducible function of (tick, x, y) alone, so replay
+/// with the same seed and inputs always yields the same actions.
+#[plugin_fn]
+pub fn decide(input: Json<DecisionInput>) -> FnResult<Json<DecisionOutput>> {
+    let input = input.0;
+
+    // Action codes: 1=North, 2=East, 3=South, 4=West, matching adjacent_terrain order.
+    let open_directions: Vec<i32> = input
+        .adjacent_terrain
+        .iter()
+        .enumerate()
+        .filter(|(_, terrain)| **terrain != BOUNDARY_TERRAIN)
+        .map(|(index, _)| (index + 1) as i32)
+        .collect();
+
+    let action = if open_directions.is_empty() {
+        0 // Wait
+    } else {
+        let seed = deterministic_seed(input.tick, input.x, input.y);
+        open_directions[(seed as usize) % open_directions.len()]
+    };
+
+    Ok(Json(DecisionOutput {
+        abi_version: ABI_VERSION,
+        action,
+    }))
+}
+
+/// SplitMix64-style mix so the same (tick, x, y) always yields the same choice.
+fn deterministic_seed(tick: u64, x: u16, y: u16) -> u64 {
+    let mut state = tick
+        .wrapping_mul(0x9E37_79B9_7F4A_7C15)
+        .wrapping_add(u64::from(x).wrapping_mul(0xBF58_476D_1CE4_E5B9))
+        .wrapping_add(u64::from(y).wrapping_mul(0x94D0_49BB_1331_11EB));
+    state ^= state >> 33;
+    state = state.wrapping_mul(0xFF51_AFD7_ED55_8CCD);
+    state ^= state >> 33;
+    state
+}
--- a/src/cli.rs
+++ b/src/cli.rs
@ -0,0 +1,220 @@
+use std::error::Error;
+use std::fs;
+use std::net::SocketAddr;
+use std::path::PathBuf;
+use std::time::{SystemTime, UNIX_EPOCH};
+
+use base64::Engine as _;
+use base64::engine::general_purpose::STANDARD as BASE64;
+use clap::{Args, Parser, Subcommand};
+use rcgen::KeyPair;
+use reqwest::{Client, Method};
+use ring::signature::Ed25519KeyPair;
+use serde::Serialize;
+
+#[derive(Debug, Parser)]
+#[command(
+    name = "wolloseum",
+    version,
+    about = "Wolloseum game server and client"
+)]
+pub struct Arguments {
+    #[command(subcommand)]
+    command: TopLevelCommand,
+}
+
+#[derive(Debug, Subcommand)]
+enum TopLevelCommand {
+    /// Start the HTTP game server.
+    Serve(ServeArguments),
+    /// Send authenticated requests to a Wolloseum server.
+    Cli(ClientArguments),
+}
+
+#[derive(Debug, Args)]
+struct ServeArguments {
+    /// Directory for certificates and the SQLite database.
+    #[arg(long, env = "WOLLOSEUM_DATA_DIR", default_value = "data")]
+    data_dir: PathBuf,
+    /// HTTP listener address.
+    #[arg(long, env = "WOLLOSEUM_BIND", default_value = "127.0.0.1:8080")]
+    bind: SocketAddr,
+}
+
+#[derive(Debug, Args)]
+struct ClientArguments {
+    /// HTTP base URL for the server.
+    #[arg(
+        long,
+        global = true,
+        env = "WOLLOSEUM_SERVER",
+        default_value = "http://127.0.0.1:8080"
+    )]
+    server: String,
+    /// Client certificate whose PEM fingerprint is the identity ID.
+    #[arg(
+        long,
+        global = true,
+        env = "WOLLOSEUM_CLIENT_CERT",
+        default_value = "data/certificates/admin-client.pem"
+    )]
+    client_cert: PathBuf,
+    /// Private key for the selected client certificate.
+    #[arg(
+        long,
+        global = true,
+        env = "WOLLOSEUM_CLIENT_KEY",
+        default_value = "data/certificates/admin-client-key.pem"
+    )]
+    client_key: PathBuf,
+    #[command(subcommand)]
+    command: ClientCommand,
+}
+
+#[derive(Debug, Subcommand)]
+enum ClientCommand {
+    /// Read the current game status.
+    Status,
+    /// Create a user and print their certificate and private key as JSON.
+    CreateUser { username: String },
+    /// Delete a player by certificate ID.
+    DeleteUser { client_id: String },
+    /// Pause the game.
+    StopGame,
+    /// Resume the game.
+    StartGame,
+    /// Upload or update this client identity's Extism WASM agent.
+    UpdateAgent { path: PathBuf },
+}
+
+pub async fn run(arguments: Arguments) -> Result<(), Box<dyn Error>> {
+    match arguments.command {
+        TopLevelCommand::Serve(arguments) => {
+            crate::server::run(arguments.data_dir, arguments.bind).await
+        }
+        TopLevelCommand::Cli(arguments) => run_client(arguments).await,
+    }
+}
+
+async fn run_client(arguments: ClientArguments) -> Result<(), Box<dyn Error>> {
+    let client = Client::builder().build()?;
+
+    let (method, path, body, needs_signature) = match arguments.command {
+        ClientCommand::Status => (Method::GET, "/api/status", Vec::new(), false),
+        ClientCommand::CreateUser { username } => (
+            Method::POST,
+            "/api/create_user",
+            serde_json::to_vec(&CreateUserBody { username })?,
+            true,
+        ),
+        ClientCommand::DeleteUser { client_id } => (
+            Method::POST,
+            "/api/delete_user",
+            serde_json::to_vec(&DeleteUserBody { client_id })?,
+            true,
+        ),
+        ClientCommand::StopGame => (Method::POST, "/api/stop_game", Vec::new(), true),
+        ClientCommand::StartGame => (Method::POST, "/api/start_game", Vec::new(), true),
+        ClientCommand::UpdateAgent { path } => {
+            (Method::POST, "/api/update_agent", fs::read(path)?, true)
+        }
+    };
+
+    let url = format!("{}{}", arguments.server.trim_end_matches('/'), path);
+    let mut request = client.request(method.clone(), url).body(body.clone());
+    if needs_signature {
+        let certificate_pem = fs::read_to_string(&arguments.client_cert)?;
+        let key = KeyPair::from_pem(&fs::read_to_string(&arguments.client_key)?)?;
+        let signer = Ed25519KeyPair::from_pkcs8(&key.serialize_der())
+            .map_err(|_| "client private key is not a valid Ed25519 PKCS#8 key")?;
+        let client_id = certificate_id(&certificate_pem);
+        let timestamp = SystemTime::now().duration_since(UNIX_EPOCH)?.as_secs();
+        let nonce = uuid::Uuid::new_v4().to_string();
+        let message = signature_message(method.as_str(), path, timestamp, &nonce, &body);
+        let signature = BASE64.encode(signer.sign(&message).as_ref());
+        request = request
+            .header("x-client-id", client_id)
+            .header("x-request-timestamp", timestamp.to_string())
+            .header("x-request-nonce", nonce)
+            .header("x-request-signature", signature);
+    }
+
+    let response = request.send().await?;
+    let status = response.status();
+    let body = response.bytes().await?;
+    if !status.is_success() {
+        return Err(format!(
+            "server returned {status}: {}",
+            String::from_utf8_lossy(&body)
+        )
+        .into());
+    }
+    if body.is_empty() {
+        println!("HTTP {status}");
+    } else if let Ok(json) = serde_json::from_slice::<serde_json::Value>(&body) {
+        println!("{}", serde_json::to_string_pretty(&json)?);
+    } else {
+        println!("{}", String::from_utf8_lossy(&body));
+    }
+    Ok(())
+}
+
+#[derive(Serialize)]
+struct CreateUserBody {
+    username: String,
+}
+
+#[derive(Serialize)]
+struct DeleteUserBody {
+    client_id: String,
+}
+
+fn signature_message(
+    method: &str,
+    path: &str,
+    timestamp: u64,
+    nonce: &str,
+    body: &[u8],
+) -> Vec<u8> {
+    let mut message = format!("{method}\n{path}\n{timestamp}\n{nonce}\n").into_bytes();
+    message.extend_from_slice(body);
+    message
+}
+
+fn certificate_id(certificate_pem: &str) -> String {
+    ring::digest::digest(&ring::digest::SHA256, certificate_pem.as_bytes())
+        .as_ref()
+        .iter()
+        .map(|byte| format!("{byte:02x}"))
+        .collect()
+}
+
+#[cfg(test)]
+mod tests {
+    use super::Arguments;
+    use clap::Parser;
+
+    #[test]
+    fn serve_and_cli_are_explicit_top_level_commands() {
+        assert!(Arguments::try_parse_from(["wolloseum"]).is_err());
+        assert!(Arguments::try_parse_from(["wolloseum", "serve"]).is_ok());
+        assert!(Arguments::try_parse_from(["wolloseum", "cli", "status"]).is_ok());
+    }
+
+    #[test]
+    fn cli_can_select_user_credentials_for_upload() {
+        assert!(
+            Arguments::try_parse_from([
+                "wolloseum",
+                "cli",
+                "--client-cert",
+                "player.pem",
+                "--client-key",
+                "player-key.pem",
+                "update-agent",
+                "agent.wasm",
+            ])
+            .is_ok()
+        );
+    }
+}
--- a/src/lib.rs
+++ b/src/lib.rs
@ -1,2 +1,4 @@
+pub mod cli;
+pub mod server;
 pub mod simulation;
 pub mod wasm_agent;
--- a/src/main.rs
+++ b/src/main.rs
@ -1,25 +1,6 @@
-use std::collections::BTreeMap;
-use wolloseum::simulation::{Action, AgentId, World};
+use clap::Parser;

-fn main() -> Result<(), Box<dyn std::error::Error>> {
-    let mut world = World::generate(0x574F4C4C, 32, 32)?;
-    let agent_id = AgentId(1);
-    world.spawn_agent(agent_id)?;
-    world.step(&BTreeMap::from([(agent_id, Action::Wait)]))?;
-
-    let (grass, water, rock) = world.terrain_counts();
-    let agent = world.agent(agent_id).expect("agent was just spawned");
-    println!(
-        "Wolloseum seed={} map={}x{} tick={} terrain=({} grass, {} water, {} rock) agent={} at {:?}",
-        world.seed(),
-        world.dimensions().0,
-        world.dimensions().1,
-        world.tick(),
-        grass,
-        water,
-        rock,
-        agent.id().0,
-        agent.position(),
-    );
-    Ok(())
+#[tokio::main]
+async fn main() -> Result<(), Box<dyn std::error::Error>> {
+    wolloseum::cli::run(wolloseum::cli::Arguments::parse()).await
 }
--- a/src/server.rs
+++ b/src/server.rs
--- a/src/wasm_agent.rs
+++ b/src/wasm_agent.rs
@ -7,7 +7,7 @@ use serde::{Deserialize, Serialize};
 use crate::simulation::{Action, AgentObservation, Direction, ObservedTerrain};

 const MAX_MODULE_BYTES: usize = 1_048_576;
-const MAX_MEMORY_PAGES: u32 = 16;
+const MAX_MEMORY_PAGES: u32 = 32;
 pub const FUEL_PER_DECISION: u64 = 100_000;
 pub const AGENT_ABI_VERSION: u16 = 1;

@ -147,7 +147,7 @@ mod tests {
            })
            .collect::<String>();
        let memory_check = if check_memory_limit {
-            "(local.set $previous (memory.grow (i32.const 16))) (local.get $previous) (i32.const -1) (i32.ne) (if (then (unreachable)))"
+            "(local.set $previous (memory.grow (i32.const 64))) (local.get $previous) (i32.const -1) (i32.ne) (if (then (unreachable)))"
        } else {
            ""
        };