Generated with:

openssl ecparam -name prime256v1 -genkey | openssl pkcs8 -topk8 -nocrypt > entropic_ecdsa.key
openssl req -new -x509 -key entropic_ecdsa.key -out entropic_ecdsa.pem -days 1000 -subj /CN=entropic\ ECDSA

openssl req -new -newkey rsa:2048 -nodes -x509 -keyout silly_signer.key -out silly_signer.pem -days 1000 -subj /CN=silly\ signer
