# [RustCrypto]: ECDSA

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[Elliptic Curve Digital Signature Algorithm (ECDSA)][1] as specified in
[FIPS 186-4][2] (Digital Signature Standard).

[Documentation][docs-link]

## About

This crate provides generic ECDSA support which can be used in the following
ways:

- Generic implementation of ECDSA usable with the following crates:
  - [`k256`] (secp256k1)
  - [`p256`] (NIST P-256)
  - [`p384`] (NIST P-384)
- Other crates which provide their own complete implementations of ECDSA can
  also leverage the types from this crate to export ECDSA functionality in a
  generic, interoperable way by leveraging [`ecdsa::Signature`] with the
  [`signature::Signer`] and [`signature::Verifier`] traits.

## ⚠️ Security Warning

The ECDSA implementation contained in this crate has never been independently
audited for security!

This crate contains a generic implementation of ECDSA which must be
instantiated using a separate crate providing a concrete implementation of
arithmetic for a particular curve. It's possible timing variability can exist
in concrete curve implementations, and thus this crate's security can only be
properly assessed for a specific elliptic curve.

USE AT YOUR OWN RISK!

## Minimum Supported Rust Version

This crate requires **Rust 1.65** at a minimum.

We may change the MSRV in the future, but it will be accompanied by a minor
version bump.

## License

All crates licensed under either of

- [Apache License, Version 2.0](http://www.apache.org/licenses/LICENSE-2.0)
- [MIT license](http://opensource.org/licenses/MIT)

at your option.

### Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted
for inclusion in the work by you, as defined in the Apache-2.0 license, shall be
dual licensed as above, without any additional terms or conditions.

[//]: # (badges)

[crate-image]: https://buildstats.info/crate/ecdsa
[crate-link]: https://crates.io/crates/ecdsa
[docs-image]: https://docs.rs/ecdsa/badge.svg
[docs-link]: https://docs.rs/ecdsa/
[build-image]: https://github.com/RustCrypto/signatures/actions/workflows/ecdsa.yml/badge.svg
[build-link]: https://github.com/RustCrypto/signatures/actions/workflows/ecdsa.yml
[license-image]: https://img.shields.io/badge/license-Apache2.0/MIT-blue.svg
[rustc-image]: https://img.shields.io/badge/rustc-1.65+-blue.svg
[chat-image]: https://img.shields.io/badge/zulip-join_chat-blue.svg
[chat-link]: https://rustcrypto.zulipchat.com/#narrow/stream/260048-signatures

[//]: # (links)

[RustCrypto]: https://github.com/RustCrypto

[//]: # (footnotes)

[1]: https://en.wikipedia.org/wiki/Elliptic_Curve_Digital_Signature_Algorithm
[2]: https://csrc.nist.gov/publications/detail/fips/186/4/final

[//]: # (docs.rs definitions)

[`ecdsa::Signature`]: https://docs.rs/ecdsa/latest/ecdsa/struct.Signature.html
[`k256`]: https://docs.rs/k256
[`p256`]: https://docs.rs/p256
[`p384`]: https://docs.rs/p384
[`signature::Signer`]: https://docs.rs/signature/latest/signature/trait.Signer.html
[`signature::Verifier`]: https://docs.rs/signature/latest/signature/trait.Verifier.html