Add content verification
Signed-off-by: Jacob Kiers <jacob@jacobkiers.net>
This commit is contained in:
parent
4b117a4743
commit
2d477bb77e
@ -73,7 +73,7 @@ In short: just because I could. It was one of those ideas I was wondering idly a
|
||||
### Has it any practical use?
|
||||
|
||||
It is not intended to have any. Since DNS records are fairly small, serving images or something would quickly start
|
||||
consuming 100s of requests per second. I wouldn't want to do that to Cloudflare 😉
|
||||
consuming 100s of requests per second. I wouldn't want to do that to Cloudflare.
|
||||
|
||||
It would be an interesting experiment to see how feasible that is.
|
||||
|
||||
|
21
content/scripts/verifier.js
Normal file
21
content/scripts/verifier.js
Normal file
@ -0,0 +1,21 @@
|
||||
class Verifier {
|
||||
/***
|
||||
* @param content Content
|
||||
*/
|
||||
async verify(content) {
|
||||
if (!window.isSecureContext) return;
|
||||
if (typeof TextEncoder === "undefined") return;
|
||||
if (typeof crypto === "undefined") return;
|
||||
const encoder = new TextEncoder();
|
||||
const digestBuffer = await crypto.subtle.digest(content.index.hashAlgorithm, encoder.encode(content.content));
|
||||
|
||||
const hashArray = Array.from(new Uint8Array(digestBuffer)); // convert buffer to byte array
|
||||
const digest = hashArray.map(b => b.toString(16).padStart(2, '0')).join(''); // convert bytes to hex string
|
||||
|
||||
if (content.index.hash === digest) {
|
||||
document.getElementById("verification").innerHTML =
|
||||
"The hash of the content is verified to correspond with the hash" +
|
||||
" in the metadata. You are now reading exactly what was intended.";
|
||||
}
|
||||
}
|
||||
}
|
49
index.html
49
index.html
@ -10,13 +10,20 @@
|
||||
class Content {
|
||||
content = "";
|
||||
type = "";
|
||||
metaData = {}
|
||||
metaData = {};
|
||||
index;
|
||||
|
||||
constructor(content, type, metaData = {})
|
||||
/***
|
||||
* @param content string
|
||||
* @param type string
|
||||
* @param index Index
|
||||
*/
|
||||
constructor(content, type, index)
|
||||
{
|
||||
this.content = content;
|
||||
this.type = type;
|
||||
this.metaData = metaData;
|
||||
this.index = index;
|
||||
this.metaData = index.metaData;
|
||||
}
|
||||
}
|
||||
|
||||
@ -24,13 +31,15 @@ class Index
|
||||
{
|
||||
mimeType = "";
|
||||
chunks = 0;
|
||||
hashAlgorithm = "";
|
||||
hash = "";
|
||||
metaData = {};
|
||||
|
||||
constructor(mimeType, chunks, hash, metaData = {})
|
||||
constructor(mimeType, chunks, hash, hashAlgorithm, metaData = {})
|
||||
{
|
||||
this.mimeType = mimeType;
|
||||
this.chunks = chunks;
|
||||
this.hashAlgorithm = hashAlgorithm;
|
||||
this.hash = hash;
|
||||
this.metaData = metaData
|
||||
}
|
||||
@ -51,7 +60,8 @@ async function readUrl(domain) {
|
||||
const chunks = await Promise.all(chunk_promises);
|
||||
const base64 = chunks.reduce((built, current) => built += current);
|
||||
|
||||
return handleContent(new Content(atob(content), index.mimeType, index.metaData));
|
||||
const content = atob(base64);
|
||||
return handleContent(new Content(content, index.mimeType, index));
|
||||
}
|
||||
|
||||
async function fetchChunk(id, hash)
|
||||
@ -84,7 +94,7 @@ async function fetchIndex(domain)
|
||||
});
|
||||
|
||||
const metadata = JSON.parse(atob(ret["m"]));
|
||||
return new Index(ret["t"], ret["c"], ret["h"], metadata);
|
||||
return new Index(ret["t"], ret["c"], ret["h"], ret["ha"], metadata);
|
||||
}
|
||||
|
||||
function handleContent(content)
|
||||
@ -110,7 +120,12 @@ function handleContent(content)
|
||||
|
||||
function handleJavascript(content)
|
||||
{
|
||||
console.log("Got some javascript!", content.content);
|
||||
console.log("Got some javascript!");
|
||||
const scripts = document.getElementById("scripts");
|
||||
const new_script = document.createElement("script");
|
||||
new_script.text = content.content;
|
||||
|
||||
scripts.appendChild(new_script);
|
||||
}
|
||||
|
||||
async function handleMarkdown(content)
|
||||
@ -128,20 +143,28 @@ async function handleMarkdown(content)
|
||||
let title = document.createElement("h1");
|
||||
title.innerHTML = content.metaData.title;
|
||||
document.getElementById("post").prepend(title)
|
||||
document.getElementById("nojs").style.visibility = "hidden";
|
||||
document.getElementById("nojs").remove();
|
||||
|
||||
if (typeof Verifier !== "undefined") {
|
||||
await (new Verifier()).verify(content);
|
||||
}
|
||||
}
|
||||
</script>
|
||||
</head>
|
||||
<body>
|
||||
<script>
|
||||
readUrl("posts-2021-08-17-serving-blog-content-over-dns-md");
|
||||
|
||||
</script>
|
||||
<div id="post"></div>
|
||||
<div id="post"></div>
|
||||
<div id="verification"></div>
|
||||
<div id="nojs">
|
||||
<h1>HTML over DNS</h1>
|
||||
<p>The content of this page is fetched using DNS over HTTP. Since that requires Javascript, please enable that to see the content.</p>
|
||||
</div>
|
||||
<div id="scripts">
|
||||
<script>
|
||||
readUrl("scripts-verifier-js").then(
|
||||
() => readUrl("posts-2021-08-17-serving-blog-content-over-dns-md")
|
||||
);
|
||||
</script>
|
||||
</div>
|
||||
</body>
|
||||
|
||||
</html>
|
Loading…
Reference in New Issue
Block a user