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From: Daniel Stenberg via curl-users <>
Date: Wed, 8 Apr 2020 10:01:04 +0200 (CEST)

On Tue, 7 Apr 2020, Joshua Abraham wrote:

>> Sure, sounds like decent thing that could be interesting to support.
> That's great to hear. I'd be open to contributing that feature!

Then I'll recommend taking further such discussions on the curl-library list
where we discuss libcurl development and related issues.

> Just a preliminary thought: this would be dependent on the underlying TLS
> library.

Yes absolutely.

> It looks like GREASE support is spotty across curl's TLS libraries.
> Examples: openssl (,
> BoringSSL:
> Should we wait until openssl has support?

My advice: if you want this feature to have a chance of landing within months
rather than years, then don't wait. I have no idea how fast the OpenSSL team
is going to work on that feature, but what you see there in github is just *an
idea* of what to implement so it might also just never happen.

curl supports 13 TLS libraries [1] and they're not all having the exact same
feature set. In fact, I they all have different pros and cons and yet curl
supports them.

If done correctly and carefully, support for feature X (like GREASE in this
case) can be implemented with and for TLS library T first, and then we can
proceed and add support for it to other backends as well over time - if/once
they offer it and if we have contributors willing and able to write the code.

Lastly: doing anything that relies on BoringSSL is of course a risk as that's
Google's TLS library explicitly done for Google with no promises to others and
they don't even do proper releases. This said, we try hard to make sure curl
remains functional with it.

[1] =

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Received on 2020-04-08