Require that EC points are on the curve.

This removes a sharp corner in the API where |ECDH_compute_key| assumed
that callers were either using ephemeral keys, or else had already
checked that the public key was on the curve.

A public key that's not on the curve can be in a small subgroup and thus
the result can leak information about the private key.

This change causes |EC_POINT_set_affine_coordinates_GFp| to require that
points are on the curve. |EC_POINT_oct2point| already does this.

Change-Id: I77d10ce117b6efd87ebb4a631be3a9630f5e6636
Reviewed-by: Adam Langley <>
3 files changed
tree: 73ab20469ed88f267315ea8fc62859cee2d6a5f0
  1. .clang-format
  2. .gitignore
  4. CMakeLists.txt
  9. codereview.settings
  10. crypto/
  11. decrepit/
  12. include/
  13. ssl/
  14. tool/
  15. 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:

  • how to port OpenSSL-using code to BoringSSL.
  • how to build BoringSSL
  • rules and guidelines for coding style.
  • include/openssl: public headers with API documentation in comments. Also available online.