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https://github.com/mdn/dom-examples/blob/224c7f14cd824fb589404ed0048e2fd1edd5bddc/web-crypto/derive-key/ecdh.js#L85

when CryptoKey (shared secret) is made and exported, it is 32 byte sequence with first zero-byte? So,

1. Why zero-byte?
2. How to get full/longer byte-sequence?

Here is the keys (a is made on server, b in browser):

1. Oookey, it not always starts with zerobyte... usually first 4 bits are zeroes.
2. These:

deriveParams: {
	name: 'HMAC'
	hash: 'SHA-512'
	length: 528
}

may be used to export full byte sequence later, but keyUsage parameter in deriveKey may not be empty, so I've used ['sign']...

Also, sometimes derived & exported key is smaller than 528, can be 520. that's strange but maybe i did something wrong again...

@wbamberg , can you comment on this one? Thanks!

@chrisdavidmills hey,

check this out: http://raw.githack.com/determin1st/httpFetch/master/test-7/index.html

works in firefox, but not in chrome :/

Due to the age of this issue I'm closing it 👍