Introduce ossl_ssize_t and use it in ASN1_STRING_set.

We have a number of APIs that cannot migrate to size_t because OpenSSL
used negative numbers as some special indicator. This makes it hard to
become size_t-clean.

However, in reality, the largest buffer size is SSIZE_MAX, or, more
accurately PTRDIFF_MAX. But every platform I've ever seen make ptrdiff_t
and size_t the same size. malloc is just obligated to fail allocations
that don't fit in ssize_t. ssize_t itself is not portable (Windows
doesn't have it), but we can define ossl_ssize_t to be ptrdiff_t.
OpenSSL also has an ossl_ssize_t (though they don't use it much), so
we're also improving compatibility.

Start this out with ASN1_STRING_set. It still internally refuses to
construct a string bigger than INT_MAX; the struct can't hold this and
even if we fix the struct, no other code, inside or outside the library,
can tolerate it. But now code which passes in a size_t (including our
own) can do so without overflow.

Bug: 428, 516
Change-Id: I17aa6971733f34dfda7d971882d0f062e92340e9
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/54953
Commit-Queue: Bob Beck <bbe@google.com>
Auto-Submit: David Benjamin <davidben@google.com>
Reviewed-by: Bob Beck <bbe@google.com>
5 files changed
tree: 819604b2c4ee4581a72469bf195b0680fbd299ee
  1. .github/
  2. crypto/
  3. decrepit/
  4. fuzz/
  5. include/
  6. rust/
  7. ssl/
  8. third_party/
  9. tool/
  10. util/
  11. .clang-format
  12. .gitignore
  13. API-CONVENTIONS.md
  14. BREAKING-CHANGES.md
  15. BUILDING.md
  16. CMakeLists.txt
  17. codereview.settings
  18. CONTRIBUTING.md
  19. FUZZING.md
  20. go.mod
  21. go.sum
  22. INCORPORATING.md
  23. LICENSE
  24. OpenSSLConfig.cmake
  25. PORTING.md
  26. README.md
  27. SANDBOXING.md
  28. sources.cmake
  29. 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: