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<head>
<meta charset="utf-8" />
<meta name="viewport" content="width=device-width, initial-scale=1" />
<title>Proof-of-work challenge</title>
<link rel="stylesheet" href="/.powxy/static/style.css" />
<script>
/*
@licstart The following is the entire license notice for the
JavaScript code in this page.
Copyright (C) 2025 Runxi Yu
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are
met:
1. Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS "AS IS" AND ANY
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IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
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SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
@licend The above is the entire license notice
for the JavaScript code in this page.
*/
</script>
</head>
<body data-identifier="{{ .Identifier }}" data-difficulty="{{ .Global.NeedBits }}">
<main>
<header>
<h1>Proof-of-work challenge</h1>
</header>
<section>
<p>This site is protected by <a href="{{ .Global.SourceURL }}">Powxy</a>{{ if .Global.Version }} {{ .Global.Version }}{{ end }}.</p>
<p>You must complete this proof-of-work challenge before you can access this site.</p>
</section>
<section>
<p>Find an nonce that, when appended to the following string, results in a SHA-256 hash that begins with at least {{ .Global.NeedBits }} zero bits.</p>
<pre id="identifier">{{ .Identifier }}</pre>
</section>
<section>
<form method="POST">
<label for="nonce">Your selected nonce, base64-encoded:</label>
<input id="nonce" name="powxy" type="text" />
<input type="submit" value="Submit" />
<p>Please note that if your submission is successful, you will be given a cookie that will allow you to access this site for a period of time without having to complete the challenge again. By pressing the submit button, you agree to be given cookies for this purpose.</p>
</form>
</section>
{{- if .Message }}
<section>
<p><strong>{{ .Message }}</strong></p>
</section>
{{- end }}
<section>
<p class="somewhat-transparent" id="solver_status">JavaScript seems to be disabled. You must solve the challenge externally.</p>
</section>
<section>
<p class="somewhat-transparent"><a href="/.powxy/static/solver.c">A C implementation of the challenge solver</a> is available.</p>
</section>
</main>
<script src="/.powxy/static/main.js">
</script>
</body>
</html>