experiment: start implementing checks in wasm (client side only so far)

Signed-off-by: Xe Iaso <me@xeiaso.net>

7 files changed, 198 insertions, 20 deletions

diff --git a/web/js/proof-of-work.mjs b/web/js/algos/fast.mjs
index 5ef3a8a..a077c22 100644
--- a/web/js/proof-of-work.mjs
+++ b/web/js/algos/fast.mjs
@@ -5,7 +5,6 @@ export default function process(
   progressCallback = null,
   threads = (navigator.hardwareConcurrency || 1),
 ) {
-  console.debug("fast algo");
   return new Promise((resolve, reject) => {
     let webWorkerURL = URL.createObjectURL(new Blob([
       '(', processTask(), ')()'
@@ -99,7 +98,6 @@ function processTask() {
 
         if (valid) {
           hash = uint8ArrayToHexString(thisHash);
-          console.log(hash);
           break;
         }
 
diff --git a/web/js/algos/sha256.mjs b/web/js/algos/sha256.mjs
new file mode 100644
index 0000000..cfea876
--- /dev/null
+++ b/web/js/algos/sha256.mjs
@@ -0,0 +1,160 @@
+import { u } from "../xeact.mjs";
+
+export default function process(
+  data,
+  difficulty = 16,
+  signal = null,
+  pc = null,
+  threads = (navigator.hardwareConcurrency || 1),
+) {
+  return new Promise(async (resolve, reject) => {
+    let webWorkerURL = URL.createObjectURL(new Blob([
+      '(', processTask(), ')()'
+    ], { type: 'application/javascript' }));
+
+    const module = await fetch(u("/.within.website/x/cmd/anubis/static/wasm/sha256.wasm"))
+      .then(resp => WebAssembly.compileStreaming(resp));
+
+    const workers = [];
+    const terminate = () => {
+      workers.forEach((w) => w.terminate());
+      if (signal != null) {
+        // clean up listener to avoid memory leak
+        signal.removeEventListener("abort", terminate);
+        if (signal.aborted) {
+          console.log("PoW aborted");
+          reject(false);
+        }
+      }
+    };
+    if (signal != null) {
+      signal.addEventListener("abort", terminate, { once: true });
+    }
+
+    for (let i = 0; i < threads; i++) {
+      let worker = new Worker(webWorkerURL);
+
+      worker.onmessage = (event) => {
+        if (typeof event.data === "number") {
+          pc?.(event.data);
+        } else {
+          terminate();
+          resolve(event.data);
+        }
+      };
+
+      worker.onerror = (event) => {
+        terminate();
+        reject(event);
+      };
+
+      worker.postMessage({
+        data,
+        difficulty,
+        nonce: i,
+        threads,
+        module,
+      });
+
+      workers.push(worker);
+    }
+
+    URL.revokeObjectURL(webWorkerURL);
+  });
+}
+
+function processTask() {
+  return function () {
+    addEventListener('message', async (event) => {
+      const importObject = {
+        anubis: {
+          anubis_update_nonce: (nonce) => postMessage(nonce),
+        }
+      };
+
+      const instance = await WebAssembly.instantiate(event.data.module, importObject);
+
+      // Get exports
+      const {
+        anubis_work,
+        data_ptr,
+        result_hash_ptr,
+        result_hash_size,
+        set_data_length,
+        memory
+      } = instance.exports;
+
+      function uint8ArrayToHex(arr) {
+        return Array.from(arr)
+          .map((c) => c.toString(16).padStart(2, "0"))
+          .join("");
+      }
+
+      function hexToUint8Array(hexString) {
+        // Remove whitespace and optional '0x' prefix
+        hexString = hexString.replace(/\s+/g, '').replace(/^0x/, '');
+
+        // Check for valid length
+        if (hexString.length % 2 !== 0) {
+          throw new Error('Invalid hex string length');
+        }
+
+        // Check for valid characters
+        if (!/^[0-9a-fA-F]+$/.test(hexString)) {
+          throw new Error('Invalid hex characters');
+        }
+
+        // Convert to Uint8Array
+        const byteArray = new Uint8Array(hexString.length / 2);
+        for (let i = 0; i < byteArray.length; i++) {
+          const byteValue = parseInt(hexString.substr(i * 2, 2), 16);
+          byteArray[i] = byteValue;
+        }
+
+        return byteArray;
+      }
+
+      // Write data to buffer
+      function writeToBuffer(data) {
+        if (data.length > 1024) throw new Error("Data exceeds buffer size");
+
+        // Get pointer and create view
+        const offset = data_ptr();
+        const buffer = new Uint8Array(memory.buffer, offset, data.length);
+
+        // Copy data
+        buffer.set(data);
+
+        // Set data length
+        set_data_length(data.length);
+      }
+
+      function readFromChallenge() {
+        const offset = result_hash_ptr();
+        const buffer = new Uint8Array(memory.buffer, offset, result_hash_size());
+
+        return buffer;
+      }
+
+      let data = event.data.data;
+      let difficulty = event.data.difficulty;
+      let hash;
+      let nonce = event.data.nonce;
+      let interand = event.data.threads;
+
+      writeToBuffer(hexToUint8Array(data));
+
+      nonce = anubis_work(difficulty, nonce, interand);
+      const challenge = readFromChallenge();
+
+      data = uint8ArrayToHex(challenge);
+
+      postMessage({
+        hash: data,
+        difficulty,
+        nonce,
+      });
+    });
+  }.toString();
+}
+
diff --git a/web/js/proof-of-work-slow.mjs b/web/js/algos/slow.mjs
index 0bdc146..2304859 100644
--- a/web/js/proof-of-work-slow.mjs
+++ b/web/js/algos/slow.mjs
@@ -7,7 +7,6 @@ export default function process(
   progressCallback = null,
   _threads = 1,
 ) {
-  console.debug("slow algo");
   return new Promise((resolve, reject) => {
     let webWorkerURL = URL.createObjectURL(new Blob([
       '(', processTask(), ')()'
diff --git a/web/js/bench.mjs b/web/js/bench.mjs
index c8c69bd..93daa90 100644
--- a/web/js/bench.mjs
+++ b/web/js/bench.mjs
@@ -1,10 +1,12 @@
-import processFast from "./proof-of-work.mjs";
-import processSlow from "./proof-of-work-slow.mjs";
+import fast from "./algos/fast.mjs";
+import slow from "./algos/slow.mjs";
+import sha256 from "./algos/sha256.mjs";
 
-const defaultDifficulty = 4;
+const defaultDifficulty = 16;
 const algorithms = {
-  fast: processFast,
-  slow: processSlow,
+  sha256: sha256,
+  fast: fast,
+  slow: slow,
 };
 
 const status = document.getElementById("status");
@@ -41,10 +43,13 @@ const benchmarkTrial = async (stats, difficulty, algorithm, signal) => {
     .map((c) => c.toString(16).padStart(2, "0"))
     .join("");
 
+  if (algorithm != "sha256") {
+    difficulty = Math.round(difficulty / 4);
+  }
+
   const t0 = performance.now();
   const { hash, nonce } = await process(challenge, Number(difficulty), signal);
   const t1 = performance.now();
-  console.log({ hash, nonce });
 
   stats.time += t1 - t0;
   stats.iters += nonce;
diff --git a/web/js/main.mjs b/web/js/main.mjs
index a093c74..79d62e9 100644
--- a/web/js/main.mjs
+++ b/web/js/main.mjs
@@ -1,17 +1,13 @@
-import processFast from "./proof-of-work.mjs";
-import processSlow from "./proof-of-work-slow.mjs";
+import fast from "./algos/fast.mjs";
+import slow from "./algos/slow.mjs";
+import sha256 from "./algos/sha256.mjs";
 import { testVideo } from "./video.mjs";
+import { u } from "./xeact.mjs";
 
 const algorithms = {
-  "fast": processFast,
-  "slow": processSlow,
-};
-
-// from Xeact
-const u = (url = "", params = {}) => {
-  let result = new URL(url, window.location.href);
-  Object.entries(params).forEach(([k, v]) => result.searchParams.set(k, v));
-  return result.toString();
+  "fast": fast,
+  "slow": slow,
+  "sha256": sha256,
 };
 
 const imageURL = (mood, cacheBuster) =>
@@ -28,6 +24,11 @@ const dependencies = [
     msg: "Your browser doesn't support web workers (Anubis uses this to avoid freezing your browser). Do you have a plugin like JShelter installed?",
     value: window.Worker,
   },
+  {
+    name: "WebAssembly",
+    msg: "Your browser doesn't have WebAssembly support. If you are running a big endian system, I'm sorry but this is something we can't work around with a polyfill.",
+    value: window.WebAssembly,
+  },
 ];
 
 function showContinueBar(hash, nonce, t0, t1) {
diff --git a/web/js/xeact.mjs b/web/js/xeact.mjs
new file mode 100644
index 0000000..5d5e8e3
--- /dev/null
+++ b/web/js/xeact.mjs
@@ -0,0 +1,13 @@
+/**
+ * Generate a relative URL from `url`, appending all key-value pairs from `params` as URL-encoded parameters.
+ *
+ * @type{function(string=, Object=): string}
+ */
+export const u = (url = "", params = {}) => {
+  let result = new URL(url, window.location.href);
+  Object.entries(params).forEach((kv) => {
+    let [k, v] = kv;
+    result.searchParams.set(k, v);
+  });
+  return result.toString();
+};
\ No newline at end of file
diff --git a/web/static/wasm/.gitignore b/web/static/wasm/.gitignore
new file mode 100644
index 0000000..c96a04f
--- /dev/null
+++ b/web/static/wasm/.gitignore
@@ -0,0 +1,2 @@
+*
+!.gitignore
\ No newline at end of file