48 lines
1.5 KiB
JavaScript
48 lines
1.5 KiB
JavaScript
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async function sha256(message) {
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const msgBuffer = new TextEncoder().encode(message);
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const hashBuffer = await crypto.subtle.digest('SHA-256', msgBuffer);
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const hashArray = Array.from(new Uint8Array(hashBuffer));
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const hashHex = hashArray.map(b => b.toString(16).padStart(2, '0')).join('');
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return hashHex;
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}
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async function startPoW() {
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document.getElementById('status').innerText = "Starting PoW...";
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// Fetch challenge from the server
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const response = await fetch('/get-challenge');
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const challenge = await response.json();
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const { nonce, difficulty } = challenge;
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let solution = 0;
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let hash = '';
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// Brute-force to find a solution
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while (true) {
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hash = await sha256(nonce + solution);
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if (hash.startsWith('0'.repeat(difficulty))) {
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break;
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}
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solution++;
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}
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document.getElementById('status').innerText = `Solution found: ${solution} (Hash: ${hash})`;
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// Send the solution back to the server for verification
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const verifyResponse = await fetch('/verify', {
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method: 'POST',
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headers: {
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'Content-Type': 'application/json',
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},
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body: JSON.stringify({ nonce, solution: solution.toString(), difficulty })
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});
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if (verifyResponse.status === 200) {
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document.getElementById('status').innerText += " - Verified!";
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} else {
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document.getElementById('status').innerText += " - Verification failed!";
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}
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}
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document.getElementById('start-pow').addEventListener('click', startPoW);
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