Add support for dummy PQ padding.

This extension will be used to measure the latency impact of potentially
sending a post-quantum key share by default. At this time it's purely
measuring the impact of the client sending the key share, not the server
replying with a ciphertext.

We could use the existing padding extension for this but that extension
doesn't allow the server to echo it, so we would need a different
extension in the future anyway. Thus we just create one now.

We can assume that modern clients will be using TLS 1.3 by the time that
PQ key-exchange is established and thus the key share will be sent in
all ClientHello messages. However, since TLS 1.3 isn't quite here yet,
this extension is also sent for TLS 1.0–1.2 ClientHellos. The latency
impact should be the same either way.

Change-Id: Ie4a17551f6589b28505797e8c54cddbe3338dfe5
Commit-Queue: Adam Langley <>
CQ-Verified: CQ bot account: <>
Reviewed-by: David Benjamin <>
12 files changed
tree: ade7a7e8511730a88f50340a6e7fb14af035881d
  1. .clang-format
  2. .github/
  3. .gitignore
  6. CMakeLists.txt
  14. codereview.settings
  15. crypto/
  16. decrepit/
  17. fipstools/
  18. fuzz/
  19. include/
  20. infra/
  21. sources.cmake
  22. ssl/
  23. third_party/
  24. tool/
  25. util/


BoringSSL is a fork of OpenSSL that is designed to meet Google's needs.

Although BoringSSL is an open source project, it is not intended for general use, as OpenSSL is. We don't recommend that third parties depend upon it. Doing so is likely to be frustrating because there are no guarantees of API or ABI stability.

Programs ship their own copies of BoringSSL when they use it and we update everything as needed when deciding to make API changes. This allows us to mostly avoid compromises in the name of compatibility. It works for us, but it may not work for you.

BoringSSL arose because Google used OpenSSL for many years in various ways and, over time, built up a large number of patches that were maintained while tracking upstream OpenSSL. As Google's product portfolio became more complex, more copies of OpenSSL sprung up and the effort involved in maintaining all these patches in multiple places was growing steadily.

Currently BoringSSL is the SSL library in Chrome/Chromium, Android (but it's not part of the NDK) and a number of other apps/programs.

There are other files in this directory which might be helpful: