Remove ex_data's dup hook.

The only place it is used is EC_KEY_{dup,copy} and no one calls that
function on an EC_KEY with ex_data. This aligns with functions like
RSAPublicKey_dup which do not copy ex_data. The logic is also somewhat
subtle in the face of malloc errors (upstream's PR 3323).

In fact, we'd even changed the function pointer signature from upstream,
so BoringSSL-only code is needed to pass this pointer in anyway. (I
haven't switched it to CRYPTO_EX_unused because there are some callers
which pass in an implementation anyway.)

Note, in upstream, the dup hook is also used for SSL_SESSIONs when those
are duplicated (for TLS 1.2 ticket renewal or TLS 1.3 resumption). Our
interpretation is that callers should treat those SSL_SESSIONs
equivalently to newly-established ones. This avoids every consumer
providing a dup hook and simplifies the interface.

(I've gone ahead and removed the TODO(fork). I don't think we'll be able
to change this API. Maybe introduce a new one, but it may not be worth
it? Then again, this API is atrocious... I've never seen anyone use argl
and argp even.)

BUG=21

Change-Id: I6c9e9d5a02347cb229d4c084c1e85125bd741d2b
Reviewed-on: https://boringssl-review.googlesource.com/16344
Reviewed-by: Adam Langley <agl@google.com>
Commit-Queue: Adam Langley <agl@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>
18 files changed
tree: 1fb6ccd386afa25e5b554e0223533eb658adefe6
  1. .github/
  2. crypto/
  3. decrepit/
  4. fipstools/
  5. fuzz/
  6. include/
  7. infra/
  8. ssl/
  9. third_party/
  10. tool/
  11. util/
  12. .clang-format
  13. .gitignore
  14. API-CONVENTIONS.md
  15. BUILDING.md
  16. CMakeLists.txt
  17. codereview.settings
  18. CONTRIBUTING.md
  19. FUZZING.md
  20. INCORPORATING.md
  21. LICENSE
  22. PORTING.md
  23. README.md
  24. sources.cmake
  25. STYLE.md
README.md

BoringSSL

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: