Remove dynamic X509_TRUST and X509_PURPOSE registration

This is not thread-safe. Even if made thread-safe, it involves
registering globals, so it's just not a good API.

Note this means that there is no longer a way to configure custom trust
OIDs or purpose checks. Evidently no one was doing that. Should a use
case arise, I don't think it should be met by this API. The things one
might want to configure here are:

- Which OID to match against X509_add1_trust_object and
  X509_add1_reject_object

- Whether self-signed certificates, if no trust objects are configured,
  also count as trust anchors

- Which EKU OID to look for up the chain

- Which legacy Netscape certificate type to look for (can we remove
  this?)

- Which key usage bits to look for in the leaf

We can simply add APIs for specifying those if we need them.

Interestingly, there's a call to check_ca inside the purpose checks
(which gets skipped if you don't configure a purpose!), but I think it
may be redundant with the X509_check_ca call in the path verifier.

Change-Id: If71ee3d0768b5fc71422852b4fcf7eb23e937dd2
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/64507
Reviewed-by: Bob Beck <bbe@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
3 files changed
tree: 8e07780ce40bc8dc7683e9dd6dceabcb212687af
  1. .github/
  2. cmake/
  3. crypto/
  4. decrepit/
  5. fuzz/
  6. include/
  7. pki/
  8. rust/
  9. ssl/
  10. third_party/
  11. tool/
  12. util/
  13. .clang-format
  14. .gitignore
  15. API-CONVENTIONS.md
  16. BREAKING-CHANGES.md
  17. BUILDING.md
  18. CMakeLists.txt
  19. codereview.settings
  20. CONTRIBUTING.md
  21. FUZZING.md
  22. go.mod
  23. go.sum
  24. INCORPORATING.md
  25. LICENSE
  26. PORTING.md
  27. README.md
  28. SANDBOXING.md
  29. sources.cmake
  30. 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.

Project links:

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