tree 45271b44c3584e39af3902345587ef58cc8dd502
parent 20462a717970cb811ecbb42650dd7bcb18561eb8
author David Brown <david.brown@linaro.org> 1511302384 -0700
committer David Brown <davidb@davidb.org> 1515516090 -0700

fix: Add back ECDSA signature support

Replace the (now broken) ECDSA code with code using the python
'cryptography' library.

Similar to the change to RSA, this changes the format that private keys
are stored, again using PKCS#8.  This supports the stronger password
protection as well.

Again, this code will still support reading the older style of public
keys, but other tools that use keys generated by this change will need
to be updated to work with the new format.

Signed-off-by: David Brown <david.brown@linaro.org>