Represents a signature algorithm and other information
necessary to verify signatures with a given public key. This is
based primarily on the public key types supported by Tink's
PemKeyType, which is in turn based on KMS's supported signing
algorithms. See https://cloud.google.com/kms/docs/algorithms. In
the future, BinAuthz might support additional public key types
independently of Tink and/or KMS.
Values:
SIGNATURE_ALGORITHM_UNSPECIFIED (0):
Not specified.
RSA_PSS_2048_SHA256 (1):
RSASSA-PSS 2048 bit key with a SHA256 digest.
RSA_PSS_3072_SHA256 (2):
RSASSA-PSS 3072 bit key with a SHA256 digest.
RSA_PSS_4096_SHA256 (3):
RSASSA-PSS 4096 bit key with a SHA256 digest.
RSA_PSS_4096_SHA512 (4):
RSASSA-PSS 4096 bit key with a SHA512 digest.
RSA_SIGN_PKCS1_2048_SHA256 (5):
RSASSA-PKCS1-v1_5 with a 2048 bit key and a SHA256 digest.
RSA_SIGN_PKCS1_3072_SHA256 (6):
RSASSA-PKCS1-v1_5 with a 3072 bit key and a SHA256 digest.
RSA_SIGN_PKCS1_4096_SHA256 (7):
RSASSA-PKCS1-v1_5 with a 4096 bit key and a SHA256 digest.
RSA_SIGN_PKCS1_4096_SHA512 (8):
RSASSA-PKCS1-v1_5 with a 4096 bit key and a SHA512 digest.
ECDSA_P256_SHA256 (9):
ECDSA on the NIST P-256 curve with a SHA256
digest.
EC_SIGN_P256_SHA256 (9):
ECDSA on the NIST P-256 curve with a SHA256
digest.
ECDSA_P384_SHA384 (10):
ECDSA on the NIST P-384 curve with a SHA384
digest.
EC_SIGN_P384_SHA384 (10):
ECDSA on the NIST P-384 curve with a SHA384
digest.
ECDSA_P521_SHA512 (11):
ECDSA on the NIST P-521 curve with a SHA512
digest.
EC_SIGN_P521_SHA512 (11):
ECDSA on the NIST P-521 curve with a SHA512
digest.
