a684152a2f
We only ever compute it for odd (actually, prime) modulus as part of BN_mod_sqrt. If we cared, we could probably drop this from most binaries. This is used to when modular square root needs Tonelli-Shanks. Modular square root is only used for compressed coordinates. Of our supported curves (I'm handwaiving away EC_GROUP_new_curve_GFp here[*]), only P-224 needs the full Tonelli-Shanks algorithm (p is 1 mod 8). That computes the Legendre symbol a bunch to find a non-square mod p. But p is known at compile-time, so we can just hard-code a sample non-square. Sadly, BN_mod_sqrt has some callers outside of crypto/ec, so there's also that. Anyway, it's also not that large of a function. [*] Glancing through SEC 2 and Brainpool, secp224r1 is the only curve listed in either document whose prime is not either 3 mod 4 or 5 mod 8. Even 5 mod 8 is rare: only secp224k1. It's unlikely anyone would notice if we broke annoying primes. Though OpenSSL does support "WTLS" curves which has an additional 1 mod 8 case. Change-Id: If36aa78c0d41253ec024f2d90692949515356cd1 Reviewed-on: https://boringssl-review.googlesource.com/15425 Reviewed-by: Adam Langley <agl@google.com> |
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| .github | ||
| crypto | ||
| decrepit | ||
| fuzz | ||
| include/openssl | ||
| infra/config | ||
| ssl | ||
| third_party | ||
| tool | ||
| util | ||
| .clang-format | ||
| .gitignore | ||
| API-CONVENTIONS.md | ||
| BUILDING.md | ||
| CMakeLists.txt | ||
| codereview.settings | ||
| CONTRIBUTING.md | ||
| FUZZING.md | ||
| INCORPORATING.md | ||
| LICENSE | ||
| PORTING.md | ||
| README.md | ||
| STYLE.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:
- PORTING.md: how to port OpenSSL-using code to BoringSSL.
- BUILDING.md: how to build BoringSSL
- INCORPORATING.md: how to incorporate BoringSSL into a project.
- API-CONVENTIONS.md: general API conventions for BoringSSL consumers and developers.
- STYLE.md: rules and guidelines for coding style.
- include/openssl: public headers with API documentation in comments. Also available online.
- FUZZING.md: information about fuzzing BoringSSL.
- CONTRIBUTING.md: how to contribute to BoringSSL.