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#933 was closed with reference to the pluggable crypto providers. But aws-lc-rs is now supported but without P-521 support.

Is your feature request related to a problem? Please describe.

rustls should support certificates signed with P-521 when using the aws-lc-rs backend.

Describe the solution you'd like

When using rustls with default options and the aws-lc-rs provider, P-521 signatures should get verified correctly.

Describe alternatives you've considered

I'm not aware of any alternatives. Support for P-521 could be opt in, but currently there is no way to do this either.

Additional context

AIUI aws-lc-rs has support for P-521 but the necessary constants are not defined in the webpki crate and the scheme is not part of the SUPPORTED_SIG_ALGS constant in the aws-lc-rs backend.