Unwanted pickiness on private key format

[dimbleby]

If I provide a private key that's not of exactly the expected format, it is wrongly treated as a filename.

Here the code insists that a private key have header -----BEGIN RSA PRIVATE KEY-----.

I believe that this is effectively forcing people to use the PKCS1 format; but PKCS8 is nowadays generally preferred.

Eg openssl genpkey -out private.key -algorithm RSA will generate a key that begins -----BEGIN PRIVATE KEY----- (note no "RSA" here).

Propose that if you want to check whether a string is a private key, it would be better to do this by using a cryptographic library and trying to load it. Failing that, please allow valid keys in modern format.