Arithmetic feature requires atomics about elliptic-curves HOT 13 CLOSED

The fix has been backported as bitvec 0.18.4, so you should now be able to cargo update to address this.

from elliptic-curves.

Yes, we're now pulling in bitvec by way of the ff crate.

This is actually a superfluous dependency (at least at present). I opened this issue about making bitvec an optional dependency of ff:

zkcrypto/ff#42

from elliptic-curves.

Just an update, this seems to be fixed with a PR for Radium: ferrilab/radium#4

from elliptic-curves.

The current v0.4.1 release doesn't have the dependency, so it must be a change between v0.5.0 ad v0.6.0 of elliptic-curve.

This is probably the commit that causes the requirement on atomics: RustCrypto/traits@59e67e0

It would be great if signing and other operations could be supported without atomics via a feature flag.

from elliptic-curves.

That would be great!

from elliptic-curves.

Otherwise I don't think signing is possible, I just keep getting this error when trying to call try_sign_recoverable_prehashed():

error[E0599]: no method named `try_sign_recoverable_prehashed` found for struct `ecdsa::signer::Signer<p256::NistP256>` in the current scope
   --> examples-features/ctap.rs:410:30
    |
410 |             let sig = signer.try_sign_recoverable_prehashed(data, None).unwrap();
    |                              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ method not found in `ecdsa::signer::Signer<p256::NistP256>`

error: aborting due to 2 previous errors; 6 warnings emitted

from elliptic-curves.

@alistair23 that method doesn't exist in the p256 crate (it's a private, inherent method in the k256 crate alone).

Here's a usage example:

https://docs.rs/p256/0.5.0-rc/p256/ecdsa/index.html#signingverification-example

from elliptic-curves.

Thanks @tarcieri, unfortunately the new sign() function depends on arithmetic which requires atomics.

from elliptic-curves.

Yeah, you need the ecdsa feature enabled in order to create signatures, which depends on arithmetic.

There's not that much that can be done about that immediately. I'd say stay on p256 0.4 until either ferrilab/radium#4 is merged and bitvec updated, and/or zkcrypto/ff#42 is merged and we can disable the bitvec dependency.

from elliptic-curves.

Hopefully one (or both) of those will be merged soon. Until then it looks like only sign_with_rng() is available, which doesn't appear to work without std.

from elliptic-curves.

@alistair23 sign_with_rng doesn't need std. If you're seeing std linkage, it's probably because some other dependency of yours is activating the std feature of rand_core.

However, sign_with_rng also needs the ecdsa feature (and with it arithmetic) and is documented as such:

https://docs.rs/p256/0.5.0-rc/p256/ecdsa/type.SigningKey.html

This is supported on crate features ecdsa-core and ecdsa only.

from elliptic-curves.

This has been fixed: ferrilab/radium#3

Do you mind updating the crate dependencies?

from elliptic-curves.

Unfortunately it’s a deep transitive dependency. Looks like bitvec needs to update to radium v0.5 then ff needs to update to a new release of bitvec. After that group needs to upgrade ff, and then elliptic-curve can update ff and group.

from elliptic-curves.