You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
41 lines
1.4 KiB
41 lines
1.4 KiB
import der, ecdsa
|
|
|
|
class UnknownCurveError(Exception):
|
|
pass
|
|
|
|
def orderlen(order):
|
|
return (1+len("%x"%order))//2 # bytes
|
|
|
|
# the NIST curves
|
|
class Curve:
|
|
def __init__(self, name, curve, generator, oid):
|
|
self.name = name
|
|
self.curve = curve
|
|
self.generator = generator
|
|
self.order = generator.order()
|
|
self.baselen = orderlen(self.order)
|
|
self.verifying_key_length = 2*self.baselen
|
|
self.signature_length = 2*self.baselen
|
|
self.oid = oid
|
|
self.encoded_oid = der.encode_oid(*oid)
|
|
|
|
NIST192p = Curve("NIST192p", ecdsa.curve_192, ecdsa.generator_192,
|
|
(1, 2, 840, 10045, 3, 1, 1))
|
|
NIST224p = Curve("NIST224p", ecdsa.curve_224, ecdsa.generator_224,
|
|
(1, 3, 132, 0, 33))
|
|
NIST256p = Curve("NIST256p", ecdsa.curve_256, ecdsa.generator_256,
|
|
(1, 2, 840, 10045, 3, 1, 7))
|
|
NIST384p = Curve("NIST384p", ecdsa.curve_384, ecdsa.generator_384,
|
|
(1, 3, 132, 0, 34))
|
|
NIST521p = Curve("NIST521p", ecdsa.curve_521, ecdsa.generator_521,
|
|
(1, 3, 132, 0, 35))
|
|
|
|
curves = [NIST192p, NIST224p, NIST256p, NIST384p, NIST521p]
|
|
|
|
def find_curve(oid_curve):
|
|
for c in curves:
|
|
if c.oid == oid_curve:
|
|
return c
|
|
raise UnknownCurveError("I don't know about the curve with oid %s."
|
|
"I only know about these: %s" %
|
|
(oid_curve, [c.name for c in curves]))
|
|
|