This adds support for parsing OpenSSH ECDSA private keys. It implements parsing for P-256, P-384, and P-521 keys. Fixes golang/go#36722 Change-Id: I77c8e0a23ed6353f6667686cc79ec14661cb10db GitHub-Last-Rev: 2324b920d080fc7ac35fbcf0a79e25161b6a7f82 GitHub-Pull-Request: golang/crypto#114 Reviewed-on: https://go-review.googlesource.com/c/crypto/+/215540 Reviewed-by: Filippo Valsorda <filippo@golang.org> Run-TryBot: Filippo Valsorda <filippo@golang.org> TryBot-Result: Gobot Gobot <gobot@golang.org>