Questions about cryptography implementations
<p>I would like to know if implementing a hash function (such as MD5, SHA1 or SHA256) is legal.</p>

<ul>
<li><p>Is it legal in the UK to implement a hash function and release it? (I know there's Regulation of Investigatory Powers Act but can it be released?)</p></li>
<li><p>In the US, do you just have to comply with exportation requirements or get your implementation licensed?</p></li>
</ul>

<p>I am planning make a software but don't want to get involved with legal stuff.</p>

<p>It is legal in the UK. In theory the government could demand that you insert a backdoor, but it isn't clear how it would work if you didn't have the technical ability to do it and what the liability would be when it was inevitably abused.</p>

united-states united-kingdom cryptography