Add some ECDSA test cases where the hash is shorter or longer than the
key length, to check that the API doesn't enforce a relationship
between the two.
For the sign_deterministic tests, the keys are
tests/data_files/ec_256_prv.pem and tests/data_files/ec_384_prv.pem
and the signatures were obtained with Python Cryptodome:
from binascii import hexlify, unhexlify
from Crypto.Hash import SHA256, SHA384
from Crypto.PublicKey import ECC
from Crypto.Signature import DSS
k2 = ECC.import_key(unhexlify("3077020101042049c9a8c18c4b885638c431cf1df1c994131609b580d4fd43a0cab17db2f13eeea00a06082a8648ce3d030107a144034200047772656f814b399279d5e1f1781fac6f099a3c5ca1b0e35351834b08b65e0b572590cdaf8f769361bcf34acfc11e5e074e8426bdde04be6e653945449617de45"))
SHA384.new(b'hello').hexdigest()
hexlify(DSS.new(k2, 'deterministic-rfc6979').sign(SHA384.new(b'hello')))
k3 = ECC.import_key(unhexlify("3081a402010104303f5d8d9be280b5696cc5cc9f94cf8af7e6b61dd6592b2ab2b3a4c607450417ec327dcdcaed7c10053d719a0574f0a76aa00706052b81040022a16403620004d9c662b50ba29ca47990450e043aeaf4f0c69b15676d112f622a71c93059af999691c5680d2b44d111579db12f4a413a2ed5c45fcfb67b5b63e00b91ebe59d09a6b1ac2c0c4282aa12317ed5914f999bc488bb132e8342cc36f2ca5e3379c747"))
SHA256.new(b'hello').hexdigest()
hexlify(DSS.new(k3, 'deterministic-rfc6979').sign(SHA256.new(b'hello')))
cb25cdd53a