...instead of hard-coding it to 20.
- This is consistent with the ChaCha implementation
- NaCl and libsodium, that this API is designed to interop with,
also support 8 and 12 round variants. The 12 round variant, in
particular, provides the same security level as the 20 round variant,
but is obviously faster.
- scrypt currently uses its own non optimized version of Salsa, just
because it use 8 rounds instead of 20. This will help remove code
duplication.
No behavior nor public API changes. The Salsa20 and XSalsa20 still
represent the 20-round variant.
We already have a LICENSE file that covers the Zig Standard Library. We
no longer need to remind everyone that the license is MIT in every single
file.
Previously this was introduced to clarify the situation for a fork of
Zig that made Zig's LICENSE file harder to find, and replaced it with
their own license that required annual payments to their company.
However that fork now appears to be dead. So there is no need to
reinforce the copyright notice in every single file.
std/crypto: use finer-grained error sets in function signatures
Returning the `crypto.Error` error set for all crypto operations
was very convenient to ensure that errors were used consistently,
and to avoid having multiple error names for the same thing.
The flipside is that callers were forced to always handle all
possible errors, even those that could never be returned by a
function.
This PR makes all functions return union sets of the actual errors
they can return.
The error sets themselves are all limited to a single error.
Larger sets are useful for platform-specific APIs, but we don't have
any of these in `std/crypto`, and I couldn't find any meaningful way
to build larger sets.
std.crypto.random
* cross platform, even freestanding
* can't fail. on initialization for some systems requires calling
os.getrandom(), in which case there are rare but theoretically
possible errors. The code panics in these cases, however the
application may choose to override the default seed function and then
handle the failure another way.
* thread-safe
* supports the full Random interface
* cryptographically secure
* no syscall required to initialize on Linux (AT_RANDOM)
* calls arc4random on systems that support it
`std.crypto.randomBytes` is removed in favor of `std.crypto.random.bytes`.
I moved some of the Random implementations into their own files in the
interest of organization.
stage2 no longer requires passing a RNG; instead it uses this API.
Closes#6704
This is a trivial implementation that just does a or[xor] loop.
However, this pattern is used by virtually all crypto libraries and
in practice, even without assembly barriers, LLVM never turns it into
code with conditional jumps, even if one of the parameters is constant.
This has been verified to still be the case with LLVM 11.0.0.
Leverage result location semantics for X25519 like we do everywhere
else in 25519/*
Also add the edwards25519->curve25519 map by the way since many
applications seem to use this to share the same key pair for encryption
and signature.
The NaCl constructions are available in pretty much all programming
languages, making them a solid choice for applications that require
interoperability.
Go includes them in the standard library, JavaScript has the popular
tweetnacl.js module, and reimplementations and ports of TweetNaCl
have been made everywhere.
Zig has almost everything that NaCl has at this point, the main
missing component being the Salsa20 cipher, on top on which NaCl's
secretboxes, boxes, and sealedboxes can be implemented.
So, here they are!
And clean the X25519 API up a little bit by the way.
