Add an API to disable RSA-PSS for certificates.

Chrome uses the platform certificate verifier and thus cannot reliably
expect PSS signatures to work in all configurations. Add an API for the
consumer to inform BoringSSL of this ability. We will then adjust our
advertisements accordingly.

Note that, because TLS 1.2 does not have the signature_algorithms_cert
extension, turning off TLS 1.3 and using this API will stop advertising
RSA-PSS. I believe this is the correct behavior given the semantics of
that code point.

The tests check the various combinations here, as well as checking that
the peer never sends signature_algorithms_cert identical to

Bug: 229
Change-Id: I8c33a93efdc9252097e3899425b49548fc42a93a
Commit-Queue: David Benjamin <>
CQ-Verified: CQ bot account: <>
Reviewed-by: Steven Valdez <>
15 files changed
tree: 499c0593a0459388f0de1952b347a8c3a2c969c8
  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: