In ed25519.zig, we checked if a test succeeds, in which case we
returned an error. This was confusing, and Andrew pointed out that
Zig weights branches against errors by default.
Add verifyStrict() functions for cofactorless verification.
Also:
- Support messages < 64 characters in the test vectors
- Allow mulDoubleBasePublic to return the identity as a regular
value. There are valid use cases for this.
added adapter to AnyWriter and GenericWriter to help bridge the gap
between old and new API
make std.testing.expectFmt work at compile-time
std.fmt no longer has a dependency on std.unicode. Formatted printing
was never properly unicode-aware. Now it no longer pretends to be.
Breakage/deprecations:
* std.fs.File.reader -> std.fs.File.deprecatedReader
* std.fs.File.writer -> std.fs.File.deprecatedWriter
* std.io.GenericReader -> std.io.Reader
* std.io.GenericWriter -> std.io.Writer
* std.io.AnyReader -> std.io.Reader
* std.io.AnyWriter -> std.io.Writer
* std.fmt.format -> std.fmt.deprecatedFormat
* std.fmt.fmtSliceEscapeLower -> std.ascii.hexEscape
* std.fmt.fmtSliceEscapeUpper -> std.ascii.hexEscape
* std.fmt.fmtSliceHexLower -> {x}
* std.fmt.fmtSliceHexUpper -> {X}
* std.fmt.fmtIntSizeDec -> {B}
* std.fmt.fmtIntSizeBin -> {Bi}
* std.fmt.fmtDuration -> {D}
* std.fmt.fmtDurationSigned -> {D}
* {} -> {f} when there is a format method
* format method signature
- anytype -> *std.io.Writer
- inferred error set -> error{WriteFailed}
- options -> (deleted)
* std.fmt.Formatted
- now takes context type explicitly
- no fmt string
When runtime safety is turned on, `Ed25519.fromSecretKey()` can
currently hit an assertion if the format of the secret key is
invalid.
Return an error instead, so that applications can recover.
Our key pair creation API was ugly and inconsistent between ecdsa
keys and other keys.
The same `generate()` function can now be used to generate key pairs,
and that function cannot fail.
For deterministic keys, a `generateDeterministic()` function is
available for all key types.
Fix comments and compilation of the benchmark by the way.
Fixes#21002
The old `CallingConvention` type is replaced with the new
`NewCallingConvention`. References to `NewCallingConvention` in the
compiler are updated accordingly. In addition, a few parts of the
standard library are updated to use the new type correctly.
Most of the functions related to points on the Edwards25519 curve
check that input points are not in a small-order subgroup.
They don't check that points are on the prime-order subgroup,
because this is expensive, and not always necessary.
However, applications may require such a check in order to
ensure that a public key is valid, and that a secret key counterpart
exists.
Many functions in the public API of libsodium related to arithmetic
over Edwards25519 also do that check unconditionally. This is
expensive, but a good way to catch bugs in protocols and
implementations.
So, add a `rejectUnexpectedSubgroup()` function to achieve this.
The documentation on the edwards25519->curve25519 conversion
function was also updated, in order to explain how to match
libsodium's behavior if necessary.
We use an addition chain to multiply the point by the order of
the prime group.
An alternative we may implement later is Pornin's point halving
technique: https://eprint.iacr.org/2022/1164.pdf
Follow up to #19079, which made test names fully qualified.
This fixes tests that now-redundant information in their test names. For example here's a fully qualified test name before the changes in this commit:
"priority_queue.test.std.PriorityQueue: shrinkAndFree"
and the same test's name after the changes in this commit:
"priority_queue.test.shrinkAndFree"
The low-level `Curve25519.fromEdwards25519()` function assumed
that the X/Y coordinates were not scaled (Z=1).
But this is not guaranteed to be the case.
In most real-world applications, the coordinates are freshly decoded,
either directly or via the `X25519.fromEd25519()` function, so this
is not an issue.
However, since we offer the ability to do that conversion after
arbitrary computations, the assertion was not correct.
Use inline to vastly simplify the exposed API. This allows a
comptime-known endian parameter to be propogated, making extra functions
for a specific endianness completely unnecessary.
* 128-bit integer multiplication with overflow
* more instruction encodings used by std inline asm
* implement the `try_ptr` air instruction
* follow correct stack frame abi
* enable full panic handler
* enable stack traces
This reverts commit 0c99ba1eab, reversing
changes made to 5f92b070bf.
This caused a CI failure when it landed in master branch due to a
128-bit `@byteSwap` in std.mem.
Most of this migration was performed automatically with `zig fmt`. There
were a few exceptions which I had to manually fix:
* `@alignCast` and `@addrSpaceCast` cannot be automatically rewritten
* `@truncate`'s fixup is incorrect for vectors
* Test cases are not formatted, and their error locations change
The majority of these are in comments, some in doc comments which might
affect the generated documentation, and a few in parameter names -
nothing that should be breaking, however.
Does what the name says: rejects generators of low-order groups.
`clearCofactor()` was previously used to do it, but for e.g.
cofactored signature verification, we don't need the result of an
actual multiplication. Only check that we didn't end up with a
low-order point, which is a faster operation.
If the noise parameter was null, we didn't use any noise at all.
We unconditionally generated random noise (`noise2`) but didn't use it.
Spotted by @cryptocode, thanks!
Key blinding allows public keys to be augmented with a secret
scalar, making multiple signatures from the same signer unlinkable.
https://datatracker.ietf.org/doc/draft-dew-cfrg-signature-key-blinding/
This is required by privacy-preserving applications such as Tor
onion services and the PrivacyPass protocol.
For 25519, it's very likely that applications would ever need the
serialized representation. Expose the value as an integer as in
other curves. Rename the internal representation from `field_size`
to `field_order` for consistency.
Also fix a common typo in `scalar.sub()`.
This valid zig code produces reasonable LLVM IR, however, on the
wasm32-wasi target, when using the wasmtime runtime, the number of
locals of the `isSquare` function exceeds 50000, causing wasmtime
to refuse to execute the binary.
The `inline` keyword in Zig is intended to be used only where it is
semantically necessary; not as an optimization hint. Otherwise, this may
produce unwanted binary bloat for the -OReleaseSmall use case.
In the future, it is possible that we may end up with both `inline`
keyword, which operates as it does in status quo, and additionally
`callconv(.inline_hint)` which has no semantic impact, but may be
observed by optimization passes.
In this commit, I also cleaned up `isSquare` by eliminating an
unnecessary mutable variable, replacing it with several local constants.
Closes#11947.
Add the ability to generate a random, canonical curve25519 scalar,
like we do for p256.
Also leverage the existing CompressedScalar type to represent these
scalars.
Frank Denis