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.
As documented in the comment right above the finalization function,
Gimli can be used as a XOF, i.e. the output doesn't have a fixed
length.
So, allow it to be used that way, just like BLAKE3.
We read and write bytes directly from the state, but in the init
function, we potentially endian-swap them.
Initialize bytes in native format since we will be reading them
in native format as well later.
Also use the public interface in the "permute" test rather than an
internal interface. The state itself is not meant to be accessed directly,
even in tests.
- use `PascalCase` for all types. So, AES256GCM is now Aes256Gcm.
- consistently use `_length` instead of mixing `_size` and `_length` for the
constants we expose
- Use `minimum_key_length` when it represents an actual minimum length.
Otherwise, use `key_length`.
- Require output buffers (for ciphertexts, macs, hashes) to be of the right
size, not at least of that size in some functions, and the exact size elsewhere.
- Use a `_bits` suffix instead of `_length` when a size is represented as a
number of bits to avoid confusion.
- Functions returning a constant-sized slice are now defined as a slice instead
of a pointer + a runtime assertion. This is the case for most hash functions.
- Use `camelCase` for all functions instead of `snake_case`.
No functional changes, but these are breaking API changes.
`DefaultCsprng` is documented as a cryptographically secure RNG.
While `ISAAC` is a CSPRNG, the variant we have, `ISAAC64` is not.
A 64 bit seed is a bit small to satisfy that claim.
We also saw it being used with the current date as a seed, that
also defeats the point of a CSPRNG.
Set `DefaultCsprng` to `Gimli` instead of `ISAAC64`, rename
the parameter from `init_s` to `secret_seed` + add a comment to
clarify what kind of seed is expected here.
Instead of directly touching the internals of the Gimli implementation
(which can change/be architecture-specific), add an `init()` function
to the state.
Our Gimli-based CSPRNG was also not backtracking resistant. Gimli
is a permutation; it can be reverted. So, if the state was ever leaked,
future secrets, but also all the previously generated ones could be
recovered. Clear the rate after a squeeze in order to prevent this.
Finally, a dumb test was added just to exercise `DefaultCsprng` since
we don't use it anywhere.
Before:
gimli-hash: 120 MiB/s
gimli-aead: 130 MiB/s
After:
gimli-hash: 195 MiB/s
gimli-aead: 208 MiB/s
Also fixes in-place decryption by the way.
If the input & output buffers were the same, decryption used to fail.
Return on decryption error in the benchmark to detect similar issues
in future AEADs even in non release-fast mode.
- 1MiB objects on the stack doesn't play well with wasmtime.
Reduce these to 512KiB so that the webassembly benchmarks can run.
- Pass expected results to a blackBox() function. Without this, in
release-fast mode, the compiler could detected unused return values,
and would produce results that didn't make sense for siphash.
- Add AEAD constructions to the benchmarks.
- Inline chacha20Core() makes it 4 times faster.
- benchmarkSignatures() -> benchmarkSignature() for consistency.
- This avoids having multiple `init()` functions for every combination
of optional parameters
- The API is consistent across all hash functions
- New options can be added later without breaking existing applications.
For example, this is going to come in handy if we implement parallelization
for BLAKE2 and BLAKE3.
- We don't have a mix of snake_case and camelCase functions any more, at
least in the public crypto API
Support for BLAKE2 salt and personalization (more commonly called context)
parameters have been implemented by the way to illustrate this.
Justification:
- reset() is unnecessary; states that have to be reused can be copied
- reset() is error-prone. Copying a previous state prevents forgetting
struct members.
- reset() forces implementation to store sensitive data (key, initial state)
in memory even when they are not needed.
- reset() is confusing as it has a different meaning elsewhere in Zig.
Instead of having all primitives and constructions share the same namespace,
they are now organized by category and function family.
Types within the same category are expected to share the exact same API.
* Implements #3768. This is a sweeping breaking change that requires
many (trivial) edits to Zig source code. Array values no longer
coerced to slices; however one may use `&` to obtain a reference to
an array value, which may then be coerced to a slice.
* Adds `IrInstruction::dump`, for debugging purposes. It's useful to
call to inspect the instruction when debugging Zig IR.
* Fixes bugs with result location semantics. See the new behavior test
cases, and compile error test cases.
* Fixes bugs with `@typeInfo` not properly resolving const values.
* Behavior tests are passing but std lib tests are not yet. There
is more work to do before merging this branch.
