|
|
- from __future__ import division
-
- from . 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, openssl_name=None):
- self.name = name
- self.openssl_name = openssl_name # maybe None
- 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), "prime192v1")
- NIST224p = Curve("NIST224p", ecdsa.curve_224, ecdsa.generator_224,
- (1, 3, 132, 0, 33), "secp224r1")
- NIST256p = Curve("NIST256p", ecdsa.curve_256, ecdsa.generator_256,
- (1, 2, 840, 10045, 3, 1, 7), "prime256v1")
- NIST384p = Curve("NIST384p", ecdsa.curve_384, ecdsa.generator_384,
- (1, 3, 132, 0, 34), "secp384r1")
- NIST521p = Curve("NIST521p", ecdsa.curve_521, ecdsa.generator_521,
- (1, 3, 132, 0, 35), "secp521r1")
- SECP256k1 = Curve("SECP256k1", ecdsa.curve_secp256k1, ecdsa.generator_secp256k1,
- (1, 3, 132, 0, 10), "secp256k1")
-
- curves = [NIST192p, NIST224p, NIST256p, NIST384p, NIST521p, SECP256k1]
-
- 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]))
|
