cmd/anubis: configurable difficulty per-bot rule (#53)

Closes #30

Introduces the "challenge" field in bot rule definitions:

```json
{
  "name": "generic-bot-catchall",
  "user_agent_regex": "(?i:bot|crawler)",
  "action": "CHALLENGE",
  "challenge": {
    "difficulty": 16,
    "report_as": 4,
    "algorithm": "slow"
  }
}
```

This makes Anubis return a challenge page for every user agent with
"bot" or "crawler" in it (case-insensitively) with difficulty 16 using
the old "slow" algorithm but reporting in the client as difficulty 4.

This is useful when you want to make certain clients in particular
suffer.

Additional validation and testing logic has been added to make sure
that users do not define "impossible" challenge settings.

If no algorithm is specified, Anubis defaults to the "fast" algorithm.

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

5 files changed, 5 insertions, 5 deletions

diff --git a/cmd/anubis/static/js/main.mjs b/cmd/anubis/static/js/main.mjs
index d1e1b86..a934289 100644
--- a/cmd/anubis/static/js/main.mjs
+++ b/cmd/anubis/static/js/main.mjs
@@ -1,2 +1,2 @@
-(()=>{function m(n,s=5,e=(navigator.hardwareConcurrency||1)){return new Promise((t,l)=>{let a=URL.createObjectURL(new Blob(["(",g(),")()"],{type:"application/javascript"})),r=[];for(let d=0;d<e;d++){let i=new Worker(a);i.onmessage=c=>{r.forEach(u=>u.terminate()),i.terminate(),t(c.data)},i.onerror=c=>{i.terminate(),l()},i.postMessage({data:n,difficulty:s,nonce:d,threads:e}),r.push(i)}URL.revokeObjectURL(a)})}function g(){return function(){let n=e=>{let t=new TextEncoder().encode(e);return crypto.subtle.digest("SHA-256",t.buffer)};function s(e){return Array.from(e).map(t=>t.toString(16).padStart(2,"0")).join("")}addEventListener("message",async e=>{let t=e.data.data,l=e.data.difficulty,a,r=e.data.nonce,d=e.data.threads;for(;;){let i=await n(t+r),c=new Uint8Array(i),u=!0;for(let o=0;o<l;o++){let f=Math.floor(o/2),p=o%2;if((c[f]>>(p===0?4:0)&15)!==0){u=!1;break}}if(u){a=s(c),console.log(a);break}r+=d}postMessage({hash:a,data:t,difficulty:l,nonce:r})})}.toString()}var w=(n="",s={})=>{let e=new URL(n,window.location.href);return Object.entries(s).forEach(t=>{let[l,a]=t;e.searchParams.set(l,a)}),e.toString()},h=(n,s)=>w(`/.within.website/x/cmd/anubis/static/img/${n}.webp`,{cacheBuster:s});(async()=>{let n=document.getElementById("status"),s=document.getElementById("image"),e=document.getElementById("title"),t=document.getElementById("spinner"),l=JSON.parse(document.getElementById("anubis_version").textContent);n.innerHTML="Calculating...";let{challenge:a,difficulty:r}=await fetch("/.within.website/x/cmd/anubis/api/make-challenge",{method:"POST"}).then(o=>{if(!o.ok)throw new Error("Failed to fetch config");return o.json()}).catch(o=>{throw e.innerHTML="Oh no!",n.innerHTML=`Failed to fetch config: ${o.message}`,s.src=h("sad"),t.innerHTML="",t.style.display="none",o});n.innerHTML=`Calculating...<br/>Difficulty: ${r}`;let d=Date.now(),{hash:i,nonce:c}=await m(a,r),u=Date.now();console.log({hash:i,nonce:c}),e.innerHTML="Success!",n.innerHTML=`Done! Took ${u-d}ms, ${c} iterations`,s.src=h("happy",l),t.innerHTML="",t.style.display="none",setTimeout(()=>{let o=window.location.href;window.location.href=w("/.within.website/x/cmd/anubis/api/pass-challenge",{response:i,nonce:c,redir:o,elapsedTime:u-d})},250)})();})();
+(()=>{function p(r,n=5,t=navigator.hardwareConcurrency||1){return console.debug("fast algo"),new Promise((e,o)=>{let s=URL.createObjectURL(new Blob(["(",y(),")()"],{type:"application/javascript"})),a=[];for(let i=0;i<t;i++){let c=new Worker(s);c.onmessage=d=>{a.forEach(u=>u.terminate()),c.terminate(),e(d.data)},c.onerror=d=>{c.terminate(),o()},c.postMessage({data:r,difficulty:n,nonce:i,threads:t}),a.push(c)}URL.revokeObjectURL(s)})}function y(){return function(){let r=t=>{let e=new TextEncoder().encode(t);return crypto.subtle.digest("SHA-256",e.buffer)};function n(t){return Array.from(t).map(e=>e.toString(16).padStart(2,"0")).join("")}addEventListener("message",async t=>{let e=t.data.data,o=t.data.difficulty,s,a=t.data.nonce,i=t.data.threads;for(;;){let c=await r(e+a),d=new Uint8Array(c),u=!0;for(let m=0;m<o;m++){let l=Math.floor(m/2),g=m%2;if((d[l]>>(g===0?4:0)&15)!==0){u=!1;break}}if(u){s=n(d),console.log(s);break}a+=i}postMessage({hash:s,data:e,difficulty:o,nonce:a})})}.toString()}function f(r,n=5,t=1){return console.debug("slow algo"),new Promise((e,o)=>{let s=URL.createObjectURL(new Blob(["(",b(),")()"],{type:"application/javascript"})),a=new Worker(s);a.onmessage=i=>{a.terminate(),e(i.data)},a.onerror=i=>{a.terminate(),o()},a.postMessage({data:r,difficulty:n}),URL.revokeObjectURL(s)})}function b(){return function(){let r=n=>{let t=new TextEncoder().encode(n);return crypto.subtle.digest("SHA-256",t.buffer).then(e=>Array.from(new Uint8Array(e)).map(o=>o.toString(16).padStart(2,"0")).join(""))};addEventListener("message",async n=>{let t=n.data.data,e=n.data.difficulty,o,s=0;do o=await r(t+s++);while(o.substring(0,e)!==Array(e+1).join("0"));s-=1,postMessage({hash:o,data:t,difficulty:e,nonce:s})})}.toString()}var L={fast:p,slow:f},w=(r="",n={})=>{let t=new URL(r,window.location.href);return Object.entries(n).forEach(e=>{let[o,s]=e;t.searchParams.set(o,s)}),t.toString()},h=(r,n)=>w(`/.within.website/x/cmd/anubis/static/img/${r}.webp`,{cacheBuster:n});(async()=>{let r=document.getElementById("status"),n=document.getElementById("image"),t=document.getElementById("title"),e=document.getElementById("spinner"),o=JSON.parse(document.getElementById("anubis_version").textContent);r.innerHTML="Calculating...";let{challenge:s,rules:a}=await fetch("/.within.website/x/cmd/anubis/api/make-challenge",{method:"POST"}).then(l=>{if(!l.ok)throw new Error("Failed to fetch config");return l.json()}).catch(l=>{throw t.innerHTML="Oh no!",r.innerHTML=`Failed to fetch config: ${l.message}`,n.src=h("sad",o),e.innerHTML="",e.style.display="none",l}),i=L[a.algorithm];if(!i){t.innerHTML="Oh no!",r.innerHTML="Failed to resolve check algorithm. You may want to reload the page.",n.src=h("sad",o),e.innerHTML="",e.style.display="none";return}r.innerHTML=`Calculating...<br/>Difficulty: ${a.report_as}`;let c=Date.now(),{hash:d,nonce:u}=await i(s,a.difficulty),m=Date.now();console.log({hash:d,nonce:u}),t.innerHTML="Success!",r.innerHTML=`Done! Took ${m-c}ms, ${u} iterations`,n.src=h("happy",o),e.innerHTML="",e.style.display="none",setTimeout(()=>{let l=window.location.href;window.location.href=w("/.within.website/x/cmd/anubis/api/pass-challenge",{response:d,nonce:u,redir:l,elapsedTime:m-c})},250)})();})();
 //# sourceMappingURL=main.mjs.map
diff --git a/cmd/anubis/static/js/main.mjs.br b/cmd/anubis/static/js/main.mjs.br
index a7b35e9..6bfd987 100644
--- a/cmd/anubis/static/js/main.mjs.br
+++ b/cmd/anubis/static/js/main.mjs.br
diff --git a/cmd/anubis/static/js/main.mjs.gz b/cmd/anubis/static/js/main.mjs.gz
index e0b648c..0e8d735 100644
--- a/cmd/anubis/static/js/main.mjs.gz
+++ b/cmd/anubis/static/js/main.mjs.gz
diff --git a/cmd/anubis/static/js/main.mjs.map b/cmd/anubis/static/js/main.mjs.map
index 3a0d564..7cad28b 100644
--- a/cmd/anubis/static/js/main.mjs.map
+++ b/cmd/anubis/static/js/main.mjs.map
@@ -1,7 +1,7 @@
 {
   "version": 3,
-  "sources": ["../../js/proof-of-work.mjs", "../../js/main.mjs"],
-  "sourcesContent": ["// https://dev.to/ratmd/simple-proof-of-work-in-javascript-3kgm\n\nexport function process(data, difficulty = 5, threads = navigator.hardwareConcurrency) {\n  return new Promise((resolve, reject) => {\n    let webWorkerURL = URL.createObjectURL(new Blob([\n      '(', processTask(), ')()'\n    ], { type: 'application/javascript' }));\n\n    const workers = [];\n\n    for (let i = 0; i < threads; i++) {\n      let worker = new Worker(webWorkerURL);\n\n      worker.onmessage = (event) => {\n        workers.forEach(worker => worker.terminate());\n        worker.terminate();\n        resolve(event.data);\n      };\n\n      worker.onerror = (event) => {\n        worker.terminate();\n        reject();\n      };\n\n      worker.postMessage({\n        data,\n        difficulty,\n        nonce: i,\n        threads,\n      });\n\n      workers.push(worker);\n    }\n\n    URL.revokeObjectURL(webWorkerURL);\n  });\n}\n\nfunction processTask() {\n  return function () {\n    const sha256 = (text) => {\n      const encoded = new TextEncoder().encode(text);\n      return crypto.subtle.digest(\"SHA-256\", encoded.buffer);\n    };\n\n    function uint8ArrayToHexString(arr) {\n      return Array.from(arr)\n        .map((c) => c.toString(16).padStart(2, \"0\"))\n        .join(\"\");\n    }\n\n    addEventListener('message', async (event) => {\n      let data = event.data.data;\n      let difficulty = event.data.difficulty;\n      let hash;\n      let nonce = event.data.nonce;\n      let threads = event.data.threads;\n\n      while (true) {\n        const currentHash = await sha256(data + nonce);\n        const thisHash = new Uint8Array(currentHash);\n        let valid = true;\n\n        for (let j = 0; j < difficulty; j++) {\n          const byteIndex = Math.floor(j / 2); // which byte we are looking at\n          const nibbleIndex = j % 2; // which nibble in the byte we are looking at (0 is high, 1 is low)\n\n          let nibble = (thisHash[byteIndex] >> (nibbleIndex === 0 ? 4 : 0)) & 0x0F; // Get the nibble\n\n          if (nibble !== 0) {\n            valid = false;\n            break;\n          }\n        }\n\n        if (valid) {\n          hash = uint8ArrayToHexString(thisHash);\n          console.log(hash);\n          break;\n        }\n\n        nonce += threads;\n      }\n\n      postMessage({\n        hash,\n        data,\n        difficulty,\n        nonce,\n      });\n    });\n  }.toString();\n}\n\n", "import { process } from './proof-of-work.mjs';\nimport { testVideo } from './video.mjs';\n\n// from Xeact\nconst u = (url = \"\", params = {}) => {\n  let result = new URL(url, window.location.href);\n  Object.entries(params).forEach((kv) => {\n    let [k, v] = kv;\n    result.searchParams.set(k, v);\n  });\n  return result.toString();\n};\n\nconst imageURL = (mood, cacheBuster) =>\n  u(`/.within.website/x/cmd/anubis/static/img/${mood}.webp`, { cacheBuster });\n\n(async () => {\n  const status = document.getElementById('status');\n  const image = document.getElementById('image');\n  const title = document.getElementById('title');\n  const spinner = document.getElementById('spinner');\n  const anubisVersion = JSON.parse(document.getElementById('anubis_version').textContent);\n\n  // const testarea = document.getElementById('testarea');\n\n  // const videoWorks = await testVideo(testarea);\n  // console.log(`videoWorks: ${videoWorks}`);\n\n  // if (!videoWorks) {\n  //   title.innerHTML = \"Oh no!\";\n  //   status.innerHTML = \"Checks failed. Please check your browser's settings and try again.\";\n  //   image.src = imageURL(\"sad\");\n  //   spinner.innerHTML = \"\";\n  //   spinner.style.display = \"none\";\n  //   return;\n  // }\n\n  status.innerHTML = 'Calculating...';\n\n  const { challenge, difficulty } = await fetch(\"/.within.website/x/cmd/anubis/api/make-challenge\", { method: \"POST\" })\n    .then(r => {\n      if (!r.ok) {\n        throw new Error(\"Failed to fetch config\");\n      }\n      return r.json();\n    })\n    .catch(err => {\n      title.innerHTML = \"Oh no!\";\n      status.innerHTML = `Failed to fetch config: ${err.message}`;\n      image.src = imageURL(\"sad\");\n      spinner.innerHTML = \"\";\n      spinner.style.display = \"none\";\n      throw err;\n    });\n\n  status.innerHTML = `Calculating...<br/>Difficulty: ${difficulty}`;\n\n  const t0 = Date.now();\n  const { hash, nonce } = await process(challenge, difficulty);\n  const t1 = Date.now();\n  console.log({ hash, nonce });\n\n  title.innerHTML = \"Success!\";\n  status.innerHTML = `Done! Took ${t1 - t0}ms, ${nonce} iterations`;\n  image.src = imageURL(\"happy\", anubisVersion);\n  spinner.innerHTML = \"\";\n  spinner.style.display = \"none\";\n\n  setTimeout(() => {\n    const redir = window.location.href;\n    window.location.href = u(\"/.within.website/x/cmd/anubis/api/pass-challenge\", { response: hash, nonce, redir, elapsedTime: t1 - t0 });\n  }, 250);\n})();"],
-  "mappings": "MAEO,SAASA,EAAQC,EAAMC,EAAa,EAAGC,EAAU,UAAU,oBAAqB,CACrF,OAAO,IAAI,QAAQ,CAACC,EAASC,IAAW,CACtC,IAAIC,EAAe,IAAI,gBAAgB,IAAI,KAAK,CAC9C,IAAKC,EAAY,EAAG,KACtB,EAAG,CAAE,KAAM,wBAAyB,CAAC,CAAC,EAEhCC,EAAU,CAAC,EAEjB,QAASC,EAAI,EAAGA,EAAIN,EAASM,IAAK,CAChC,IAAIC,EAAS,IAAI,OAAOJ,CAAY,EAEpCI,EAAO,UAAaC,GAAU,CAC5BH,EAAQ,QAAQE,GAAUA,EAAO,UAAU,CAAC,EAC5CA,EAAO,UAAU,EACjBN,EAAQO,EAAM,IAAI,CACpB,EAEAD,EAAO,QAAWC,GAAU,CAC1BD,EAAO,UAAU,EACjBL,EAAO,CACT,EAEAK,EAAO,YAAY,CACjB,KAAAT,EACA,WAAAC,EACA,MAAOO,EACP,QAAAN,CACF,CAAC,EAEDK,EAAQ,KAAKE,CAAM,CACrB,CAEA,IAAI,gBAAgBJ,CAAY,CAClC,CAAC,CACH,CAEA,SAASC,GAAc,CACrB,OAAO,UAAY,CACjB,IAAMK,EAAUC,GAAS,CACvB,IAAMC,EAAU,IAAI,YAAY,EAAE,OAAOD,CAAI,EAC7C,OAAO,OAAO,OAAO,OAAO,UAAWC,EAAQ,MAAM,CACvD,EAEA,SAASC,EAAsBC,EAAK,CAClC,OAAO,MAAM,KAAKA,CAAG,EAClB,IAAKC,GAAMA,EAAE,SAAS,EAAE,EAAE,SAAS,EAAG,GAAG,CAAC,EAC1C,KAAK,EAAE,CACZ,CAEA,iBAAiB,UAAW,MAAON,GAAU,CAC3C,IAAIV,EAAOU,EAAM,KAAK,KAClBT,EAAaS,EAAM,KAAK,WACxBO,EACAC,EAAQR,EAAM,KAAK,MACnBR,EAAUQ,EAAM,KAAK,QAEzB,OAAa,CACX,IAAMS,EAAc,MAAMR,EAAOX,EAAOkB,CAAK,EACvCE,EAAW,IAAI,WAAWD,CAAW,EACvCE,EAAQ,GAEZ,QAASC,EAAI,EAAGA,EAAIrB,EAAYqB,IAAK,CACnC,IAAMC,EAAY,KAAK,MAAMD,EAAI,CAAC,EAC5BE,EAAcF,EAAI,EAIxB,IAFcF,EAASG,CAAS,IAAMC,IAAgB,EAAI,EAAI,GAAM,MAErD,EAAG,CAChBH,EAAQ,GACR,KACF,CACF,CAEA,GAAIA,EAAO,CACTJ,EAAOH,EAAsBM,CAAQ,EACrC,QAAQ,IAAIH,CAAI,EAChB,KACF,CAEAC,GAAShB,CACX,CAEA,YAAY,CACV,KAAAe,EACA,KAAAjB,EACA,WAAAC,EACA,MAAAiB,CACF,CAAC,CACH,CAAC,CACH,EAAE,SAAS,CACb,CCxFA,IAAMO,EAAI,CAACC,EAAM,GAAIC,EAAS,CAAC,IAAM,CACnC,IAAIC,EAAS,IAAI,IAAIF,EAAK,OAAO,SAAS,IAAI,EAC9C,cAAO,QAAQC,CAAM,EAAE,QAASE,GAAO,CACrC,GAAI,CAACC,EAAGC,CAAC,EAAIF,EACbD,EAAO,aAAa,IAAIE,EAAGC,CAAC,CAC9B,CAAC,EACMH,EAAO,SAAS,CACzB,EAEMI,EAAW,CAACC,EAAMC,IACtBT,EAAE,4CAA4CQ,CAAI,QAAS,CAAE,YAAAC,CAAY,CAAC,GAE3E,SAAY,CACX,IAAMC,EAAS,SAAS,eAAe,QAAQ,EACzCC,EAAQ,SAAS,eAAe,OAAO,EACvCC,EAAQ,SAAS,eAAe,OAAO,EACvCC,EAAU,SAAS,eAAe,SAAS,EAC3CC,EAAgB,KAAK,MAAM,SAAS,eAAe,gBAAgB,EAAE,WAAW,EAgBtFJ,EAAO,UAAY,iBAEnB,GAAM,CAAE,UAAAK,EAAW,WAAAC,CAAW,EAAI,MAAM,MAAM,mDAAoD,CAAE,OAAQ,MAAO,CAAC,EACjH,KAAKC,GAAK,CACT,GAAI,CAACA,EAAE,GACL,MAAM,IAAI,MAAM,wBAAwB,EAE1C,OAAOA,EAAE,KAAK,CAChB,CAAC,EACA,MAAMC,GAAO,CACZ,MAAAN,EAAM,UAAY,SAClBF,EAAO,UAAY,2BAA2BQ,EAAI,OAAO,GACzDP,EAAM,IAAMJ,EAAS,KAAK,EAC1BM,EAAQ,UAAY,GACpBA,EAAQ,MAAM,QAAU,OAClBK,CACR,CAAC,EAEHR,EAAO,UAAY,kCAAkCM,CAAU,GAE/D,IAAMG,EAAK,KAAK,IAAI,EACd,CAAE,KAAAC,EAAM,MAAAC,CAAM,EAAI,MAAMC,EAAQP,EAAWC,CAAU,EACrDO,EAAK,KAAK,IAAI,EACpB,QAAQ,IAAI,CAAE,KAAAH,EAAM,MAAAC,CAAM,CAAC,EAE3BT,EAAM,UAAY,WAClBF,EAAO,UAAY,cAAca,EAAKJ,CAAE,OAAOE,CAAK,cACpDV,EAAM,IAAMJ,EAAS,QAASO,CAAa,EAC3CD,EAAQ,UAAY,GACpBA,EAAQ,MAAM,QAAU,OAExB,WAAW,IAAM,CACf,IAAMW,EAAQ,OAAO,SAAS,KAC9B,OAAO,SAAS,KAAOxB,EAAE,mDAAoD,CAAE,SAAUoB,EAAM,MAAAC,EAAO,MAAAG,EAAO,YAAaD,EAAKJ,CAAG,CAAC,CACrI,EAAG,GAAG,CACR,GAAG",
-  "names": ["process", "data", "difficulty", "threads", "resolve", "reject", "webWorkerURL", "processTask", "workers", "i", "worker", "event", "sha256", "text", "encoded", "uint8ArrayToHexString", "arr", "c", "hash", "nonce", "currentHash", "thisHash", "valid", "j", "byteIndex", "nibbleIndex", "u", "url", "params", "result", "kv", "k", "v", "imageURL", "mood", "cacheBuster", "status", "image", "title", "spinner", "anubisVersion", "challenge", "difficulty", "r", "err", "t0", "hash", "nonce", "process", "t1", "redir"]
+  "sources": ["../../js/proof-of-work.mjs", "../../js/proof-of-work-slow.mjs", "../../js/main.mjs"],
+  "sourcesContent": ["export default function process(data, difficulty = 5, threads = (navigator.hardwareConcurrency || 1)) {\n  console.debug(\"fast algo\");\n  return new Promise((resolve, reject) => {\n    let webWorkerURL = URL.createObjectURL(new Blob([\n      '(', processTask(), ')()'\n    ], { type: 'application/javascript' }));\n\n    const workers = [];\n\n    for (let i = 0; i < threads; i++) {\n      let worker = new Worker(webWorkerURL);\n\n      worker.onmessage = (event) => {\n        workers.forEach(worker => worker.terminate());\n        worker.terminate();\n        resolve(event.data);\n      };\n\n      worker.onerror = (event) => {\n        worker.terminate();\n        reject();\n      };\n\n      worker.postMessage({\n        data,\n        difficulty,\n        nonce: i,\n        threads,\n      });\n\n      workers.push(worker);\n    }\n\n    URL.revokeObjectURL(webWorkerURL);\n  });\n}\n\nfunction processTask() {\n  return function () {\n    const sha256 = (text) => {\n      const encoded = new TextEncoder().encode(text);\n      return crypto.subtle.digest(\"SHA-256\", encoded.buffer);\n    };\n\n    function uint8ArrayToHexString(arr) {\n      return Array.from(arr)\n        .map((c) => c.toString(16).padStart(2, \"0\"))\n        .join(\"\");\n    }\n\n    addEventListener('message', async (event) => {\n      let data = event.data.data;\n      let difficulty = event.data.difficulty;\n      let hash;\n      let nonce = event.data.nonce;\n      let threads = event.data.threads;\n\n      while (true) {\n        const currentHash = await sha256(data + nonce);\n        const thisHash = new Uint8Array(currentHash);\n        let valid = true;\n\n        for (let j = 0; j < difficulty; j++) {\n          const byteIndex = Math.floor(j / 2); // which byte we are looking at\n          const nibbleIndex = j % 2; // which nibble in the byte we are looking at (0 is high, 1 is low)\n\n          let nibble = (thisHash[byteIndex] >> (nibbleIndex === 0 ? 4 : 0)) & 0x0F; // Get the nibble\n\n          if (nibble !== 0) {\n            valid = false;\n            break;\n          }\n        }\n\n        if (valid) {\n          hash = uint8ArrayToHexString(thisHash);\n          console.log(hash);\n          break;\n        }\n\n        nonce += threads;\n      }\n\n      postMessage({\n        hash,\n        data,\n        difficulty,\n        nonce,\n      });\n    });\n  }.toString();\n}\n\n", "// https://dev.to/ratmd/simple-proof-of-work-in-javascript-3kgm\n\nexport default function process(data, difficulty = 5, _threads = 1) {\n  console.debug(\"slow algo\");\n  return new Promise((resolve, reject) => {\n    let webWorkerURL = URL.createObjectURL(new Blob([\n      '(', processTask(), ')()'\n    ], { type: 'application/javascript' }));\n\n    let worker = new Worker(webWorkerURL);\n\n    worker.onmessage = (event) => {\n      worker.terminate();\n      resolve(event.data);\n    };\n\n    worker.onerror = (event) => {\n      worker.terminate();\n      reject();\n    };\n\n    worker.postMessage({\n      data,\n      difficulty\n    });\n\n    URL.revokeObjectURL(webWorkerURL);\n  });\n}\n\nfunction processTask() {\n  return function () {\n    const sha256 = (text) => {\n      const encoded = new TextEncoder().encode(text);\n      return crypto.subtle.digest(\"SHA-256\", encoded.buffer)\n        .then((result) =>\n          Array.from(new Uint8Array(result))\n            .map((c) => c.toString(16).padStart(2, \"0\"))\n            .join(\"\"),\n        );\n    };\n\n    addEventListener('message', async (event) => {\n      let data = event.data.data;\n      let difficulty = event.data.difficulty;\n\n      let hash;\n      let nonce = 0;\n      do {\n        hash = await sha256(data + nonce++);\n      } while (hash.substring(0, difficulty) !== Array(difficulty + 1).join('0'));\n\n      nonce -= 1; // last nonce was post-incremented\n\n      postMessage({\n        hash,\n        data,\n        difficulty,\n        nonce,\n      });\n    });\n  }.toString();\n}", "import processFast from \"./proof-of-work.mjs\";\nimport processSlow from \"./proof-of-work-slow.mjs\";\nimport { testVideo } from \"./video.mjs\";\n\nconst algorithms = {\n  \"fast\": processFast,\n  \"slow\": processSlow,\n}\n\n// from Xeact\nconst u = (url = \"\", params = {}) => {\n  let result = new URL(url, window.location.href);\n  Object.entries(params).forEach((kv) => {\n    let [k, v] = kv;\n    result.searchParams.set(k, v);\n  });\n  return result.toString();\n};\n\nconst imageURL = (mood, cacheBuster) =>\n  u(`/.within.website/x/cmd/anubis/static/img/${mood}.webp`, { cacheBuster });\n\n(async () => {\n  const status = document.getElementById('status');\n  const image = document.getElementById('image');\n  const title = document.getElementById('title');\n  const spinner = document.getElementById('spinner');\n  const anubisVersion = JSON.parse(document.getElementById('anubis_version').textContent);\n\n  // const testarea = document.getElementById('testarea');\n\n  // const videoWorks = await testVideo(testarea);\n  // console.log(`videoWorks: ${videoWorks}`);\n\n  // if (!videoWorks) {\n  //   title.innerHTML = \"Oh no!\";\n  //   status.innerHTML = \"Checks failed. Please check your browser's settings and try again.\";\n  //   image.src = imageURL(\"sad\");\n  //   spinner.innerHTML = \"\";\n  //   spinner.style.display = \"none\";\n  //   return;\n  // }\n\n  status.innerHTML = 'Calculating...';\n\n  const { challenge, rules } = await fetch(\"/.within.website/x/cmd/anubis/api/make-challenge\", { method: \"POST\" })\n    .then(r => {\n      if (!r.ok) {\n        throw new Error(\"Failed to fetch config\");\n      }\n      return r.json();\n    })\n    .catch(err => {\n      title.innerHTML = \"Oh no!\";\n      status.innerHTML = `Failed to fetch config: ${err.message}`;\n      image.src = imageURL(\"sad\", anubisVersion);\n      spinner.innerHTML = \"\";\n      spinner.style.display = \"none\";\n      throw err;\n    });\n\n  const process = algorithms[rules.algorithm];\n  if (!process) {\n    title.innerHTML = \"Oh no!\";\n    status.innerHTML = `Failed to resolve check algorithm. You may want to reload the page.`;\n    image.src = imageURL(\"sad\", anubisVersion);\n    spinner.innerHTML = \"\";\n    spinner.style.display = \"none\";\n    return;\n  }\n\n  status.innerHTML = `Calculating...<br/>Difficulty: ${rules.report_as}`;\n\n  const t0 = Date.now();\n  const { hash, nonce } = await process(challenge, rules.difficulty);\n  const t1 = Date.now();\n  console.log({ hash, nonce });\n\n  title.innerHTML = \"Success!\";\n  status.innerHTML = `Done! Took ${t1 - t0}ms, ${nonce} iterations`;\n  image.src = imageURL(\"happy\", anubisVersion);\n  spinner.innerHTML = \"\";\n  spinner.style.display = \"none\";\n\n  setTimeout(() => {\n    const redir = window.location.href;\n    window.location.href = u(\"/.within.website/x/cmd/anubis/api/pass-challenge\", { response: hash, nonce, redir, elapsedTime: t1 - t0 });\n  }, 250);\n})();"],
+  "mappings": "MAAe,SAARA,EAAyBC,EAAMC,EAAa,EAAGC,EAAW,UAAU,qBAAuB,EAAI,CACpG,eAAQ,MAAM,WAAW,EAClB,IAAI,QAAQ,CAACC,EAASC,IAAW,CACtC,IAAIC,EAAe,IAAI,gBAAgB,IAAI,KAAK,CAC9C,IAAKC,EAAY,EAAG,KACtB,EAAG,CAAE,KAAM,wBAAyB,CAAC,CAAC,EAEhCC,EAAU,CAAC,EAEjB,QAAS,EAAI,EAAG,EAAIL,EAAS,IAAK,CAChC,IAAIM,EAAS,IAAI,OAAOH,CAAY,EAEpCG,EAAO,UAAaC,GAAU,CAC5BF,EAAQ,QAAQC,GAAUA,EAAO,UAAU,CAAC,EAC5CA,EAAO,UAAU,EACjBL,EAAQM,EAAM,IAAI,CACpB,EAEAD,EAAO,QAAWC,GAAU,CAC1BD,EAAO,UAAU,EACjBJ,EAAO,CACT,EAEAI,EAAO,YAAY,CACjB,KAAAR,EACA,WAAAC,EACA,MAAO,EACP,QAAAC,CACF,CAAC,EAEDK,EAAQ,KAAKC,CAAM,CACrB,CAEA,IAAI,gBAAgBH,CAAY,CAClC,CAAC,CACH,CAEA,SAASC,GAAc,CACrB,OAAO,UAAY,CACjB,IAAMI,EAAUC,GAAS,CACvB,IAAMC,EAAU,IAAI,YAAY,EAAE,OAAOD,CAAI,EAC7C,OAAO,OAAO,OAAO,OAAO,UAAWC,EAAQ,MAAM,CACvD,EAEA,SAASC,EAAsBC,EAAK,CAClC,OAAO,MAAM,KAAKA,CAAG,EAClB,IAAKC,GAAMA,EAAE,SAAS,EAAE,EAAE,SAAS,EAAG,GAAG,CAAC,EAC1C,KAAK,EAAE,CACZ,CAEA,iBAAiB,UAAW,MAAON,GAAU,CAC3C,IAAIT,EAAOS,EAAM,KAAK,KAClBR,EAAaQ,EAAM,KAAK,WACxBO,EACAC,EAAQR,EAAM,KAAK,MACnBP,EAAUO,EAAM,KAAK,QAEzB,OAAa,CACX,IAAMS,EAAc,MAAMR,EAAOV,EAAOiB,CAAK,EACvCE,EAAW,IAAI,WAAWD,CAAW,EACvCE,EAAQ,GAEZ,QAASC,EAAI,EAAGA,EAAIpB,EAAYoB,IAAK,CACnC,IAAMC,EAAY,KAAK,MAAMD,EAAI,CAAC,EAC5BE,EAAcF,EAAI,EAIxB,IAFcF,EAASG,CAAS,IAAMC,IAAgB,EAAI,EAAI,GAAM,MAErD,EAAG,CAChBH,EAAQ,GACR,KACF,CACF,CAEA,GAAIA,EAAO,CACTJ,EAAOH,EAAsBM,CAAQ,EACrC,QAAQ,IAAIH,CAAI,EAChB,KACF,CAEAC,GAASf,CACX,CAEA,YAAY,CACV,KAAAc,EACA,KAAAhB,EACA,WAAAC,EACA,MAAAgB,CACF,CAAC,CACH,CAAC,CACH,EAAE,SAAS,CACb,CCzFe,SAARO,EAAyBC,EAAMC,EAAa,EAAGC,EAAW,EAAG,CAClE,eAAQ,MAAM,WAAW,EAClB,IAAI,QAAQ,CAACC,EAASC,IAAW,CACtC,IAAIC,EAAe,IAAI,gBAAgB,IAAI,KAAK,CAC9C,IAAKC,EAAY,EAAG,KACtB,EAAG,CAAE,KAAM,wBAAyB,CAAC,CAAC,EAElCC,EAAS,IAAI,OAAOF,CAAY,EAEpCE,EAAO,UAAaC,GAAU,CAC5BD,EAAO,UAAU,EACjBJ,EAAQK,EAAM,IAAI,CACpB,EAEAD,EAAO,QAAWC,GAAU,CAC1BD,EAAO,UAAU,EACjBH,EAAO,CACT,EAEAG,EAAO,YAAY,CACjB,KAAAP,EACA,WAAAC,CACF,CAAC,EAED,IAAI,gBAAgBI,CAAY,CAClC,CAAC,CACH,CAEA,SAASC,GAAc,CACrB,OAAO,UAAY,CACjB,IAAMG,EAAUC,GAAS,CACvB,IAAMC,EAAU,IAAI,YAAY,EAAE,OAAOD,CAAI,EAC7C,OAAO,OAAO,OAAO,OAAO,UAAWC,EAAQ,MAAM,EAClD,KAAMC,GACL,MAAM,KAAK,IAAI,WAAWA,CAAM,CAAC,EAC9B,IAAKC,GAAMA,EAAE,SAAS,EAAE,EAAE,SAAS,EAAG,GAAG,CAAC,EAC1C,KAAK,EAAE,CACZ,CACJ,EAEA,iBAAiB,UAAW,MAAOL,GAAU,CAC3C,IAAIR,EAAOQ,EAAM,KAAK,KAClBP,EAAaO,EAAM,KAAK,WAExBM,EACAC,EAAQ,EACZ,GACED,EAAO,MAAML,EAAOT,EAAOe,GAAO,QAC3BD,EAAK,UAAU,EAAGb,CAAU,IAAM,MAAMA,EAAa,CAAC,EAAE,KAAK,GAAG,GAEzEc,GAAS,EAET,YAAY,CACV,KAAAD,EACA,KAAAd,EACA,WAAAC,EACA,MAAAc,CACF,CAAC,CACH,CAAC,CACH,EAAE,SAAS,CACb,CC1DA,IAAMC,EAAa,CACjB,KAAQC,EACR,KAAQA,CACV,EAGMC,EAAI,CAACC,EAAM,GAAIC,EAAS,CAAC,IAAM,CACnC,IAAIC,EAAS,IAAI,IAAIF,EAAK,OAAO,SAAS,IAAI,EAC9C,cAAO,QAAQC,CAAM,EAAE,QAASE,GAAO,CACrC,GAAI,CAACC,EAAGC,CAAC,EAAIF,EACbD,EAAO,aAAa,IAAIE,EAAGC,CAAC,CAC9B,CAAC,EACMH,EAAO,SAAS,CACzB,EAEMI,EAAW,CAACC,EAAMC,IACtBT,EAAE,4CAA4CQ,CAAI,QAAS,CAAE,YAAAC,CAAY,CAAC,GAE3E,SAAY,CACX,IAAMC,EAAS,SAAS,eAAe,QAAQ,EACzCC,EAAQ,SAAS,eAAe,OAAO,EACvCC,EAAQ,SAAS,eAAe,OAAO,EACvCC,EAAU,SAAS,eAAe,SAAS,EAC3CC,EAAgB,KAAK,MAAM,SAAS,eAAe,gBAAgB,EAAE,WAAW,EAgBtFJ,EAAO,UAAY,iBAEnB,GAAM,CAAE,UAAAK,EAAW,MAAAC,CAAM,EAAI,MAAM,MAAM,mDAAoD,CAAE,OAAQ,MAAO,CAAC,EAC5G,KAAKC,GAAK,CACT,GAAI,CAACA,EAAE,GACL,MAAM,IAAI,MAAM,wBAAwB,EAE1C,OAAOA,EAAE,KAAK,CAChB,CAAC,EACA,MAAMC,GAAO,CACZ,MAAAN,EAAM,UAAY,SAClBF,EAAO,UAAY,2BAA2BQ,EAAI,OAAO,GACzDP,EAAM,IAAMJ,EAAS,MAAOO,CAAa,EACzCD,EAAQ,UAAY,GACpBA,EAAQ,MAAM,QAAU,OAClBK,CACR,CAAC,EAEGnB,EAAUD,EAAWkB,EAAM,SAAS,EAC1C,GAAI,CAACjB,EAAS,CACZa,EAAM,UAAY,SAClBF,EAAO,UAAY,sEACnBC,EAAM,IAAMJ,EAAS,MAAOO,CAAa,EACzCD,EAAQ,UAAY,GACpBA,EAAQ,MAAM,QAAU,OACxB,MACF,CAEAH,EAAO,UAAY,kCAAkCM,EAAM,SAAS,GAEpE,IAAMG,EAAK,KAAK,IAAI,EACd,CAAE,KAAAC,EAAM,MAAAC,CAAM,EAAI,MAAMtB,EAAQgB,EAAWC,EAAM,UAAU,EAC3DM,EAAK,KAAK,IAAI,EACpB,QAAQ,IAAI,CAAE,KAAAF,EAAM,MAAAC,CAAM,CAAC,EAE3BT,EAAM,UAAY,WAClBF,EAAO,UAAY,cAAcY,EAAKH,CAAE,OAAOE,CAAK,cACpDV,EAAM,IAAMJ,EAAS,QAASO,CAAa,EAC3CD,EAAQ,UAAY,GACpBA,EAAQ,MAAM,QAAU,OAExB,WAAW,IAAM,CACf,IAAMU,EAAQ,OAAO,SAAS,KAC9B,OAAO,SAAS,KAAOvB,EAAE,mDAAoD,CAAE,SAAUoB,EAAM,MAAAC,EAAO,MAAAE,EAAO,YAAaD,EAAKH,CAAG,CAAC,CACrI,EAAG,GAAG,CACR,GAAG",
+  "names": ["process", "data", "difficulty", "threads", "resolve", "reject", "webWorkerURL", "processTask", "workers", "worker", "event", "sha256", "text", "encoded", "uint8ArrayToHexString", "arr", "c", "hash", "nonce", "currentHash", "thisHash", "valid", "j", "byteIndex", "nibbleIndex", "process", "data", "difficulty", "_threads", "resolve", "reject", "webWorkerURL", "processTask", "worker", "event", "sha256", "text", "encoded", "result", "c", "hash", "nonce", "algorithms", "process", "u", "url", "params", "result", "kv", "k", "v", "imageURL", "mood", "cacheBuster", "status", "image", "title", "spinner", "anubisVersion", "challenge", "rules", "r", "err", "t0", "hash", "nonce", "t1", "redir"]
 }
diff --git a/cmd/anubis/static/js/main.mjs.zst b/cmd/anubis/static/js/main.mjs.zst
index 8903e1e..4ed5ca7 100644
--- a/cmd/anubis/static/js/main.mjs.zst
+++ b/cmd/anubis/static/js/main.mjs.zst