def getPublicKeyHexifiedString(self):
"""Returns the EC public key as a hex string using the uncompressed
point representation. This is intended to be used in the encoder
functions, as it surrounds the value with ''H to indicate its type."""
# We need to extract the point that represents this key.
# The library encoding of the key is an 8-byte id, followed by 2
# bytes for the key length in bits, followed by the point on the
# curve (represented by two python longs). There appear to also
# be 2 bytes indicating the length of the point as encoded, but
# Decoder takes care of that.
encoded = self.key.encode()
_, _, points = encoding.Decoder(encoded).int(8).int(2).point(2).out()
# '04' indicates that the points are in uncompressed form.
return "'%s%s%s'H" % ('04', longToEvenLengthHexString(
points[0]), longToEvenLengthHexString(points[1]))
def asSubjectPublicKeyInfo(self):
"""Returns a subject public key info representing
this key for use by pyasn1."""
algorithmIdentifier = rfc2459.AlgorithmIdentifier()
algorithmIdentifier['algorithm'] = ecPublicKey
algorithmIdentifier['parameters'] = self.keyOID
spki = rfc2459.SubjectPublicKeyInfo()
spki['algorithm'] = algorithmIdentifier
# We need to extract the point that represents this key.
# The library encoding of the key is an 8-byte id, followed by 2
# bytes for the key length in bits, followed by the point on the
# curve (represented by two python longs). There appear to also
# be 2 bytes indicating the length of the point as encoded, but
# Decoder takes care of that.
encoded = self.key.encode()
_, _, points = encoding.Decoder(encoded).int(8).int(2).point(2).out()
# '04' indicates that the points are in uncompressed form.
hexifiedBitString = "'%s%s%s'H" % ('04', longToEvenLengthHexString(points[0]),
longToEvenLengthHexString(points[1]))
subjectPublicKey = univ.BitString(hexifiedBitString)
spki['subjectPublicKey'] = subjectPublicKey
return spki