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remove binary curve support (#14291)
* remove binary curve support binary curves are rarely used, contain additional dangers, and may not be supported in some of our alternate backends. * more sect * better assert * unwrap :feelsbadman:
1 parent de9dae3 commit 341dc6a

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Lines changed: 37 additions & 516 deletions

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‎CHANGELOG.rst‎

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@@ -10,6 +10,9 @@ Changelog
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* Support for Python 3.8 is deprecated and will be removed in the next
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``cryptography`` release.
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* **BACKWARDS INCOMPATIBLE:** Support for binary elliptic curves
14+
(``SECT*`` classes) has been removed. These curves are rarely used and
15+
have additional security considerations that make them undesirable.
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* **BACKWARDS INCOMPATIBLE:** Support for OpenSSL 1.1.x has been removed.
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OpenSSL 3.0.0 or later is now required. LibreSSL, BoringSSL, and AWS-LC
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continue to be supported.

‎docs/hazmat/primitives/asymmetric/ec.rst‎

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@@ -395,87 +395,6 @@ All named curves are instances of :class:`EllipticCurve`.
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Brainpool curve specified in :rfc:`5639`. These curves are discouraged
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for new systems.
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.. class:: SECT571K1
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.. versionadded:: 0.5
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SECG curve ``sect571k1``. Also called NIST K-571. These binary curves are
403-
discouraged for new systems.
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.. class:: SECT409K1
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.. versionadded:: 0.5
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SECG curve ``sect409k1``. Also called NIST K-409. These binary curves are
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discouraged for new systems.
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.. class:: SECT283K1
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.. versionadded:: 0.5
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SECG curve ``sect283k1``. Also called NIST K-283. These binary curves are
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discouraged for new systems.
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.. class:: SECT233K1
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.. versionadded:: 0.5
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SECG curve ``sect233k1``. Also called NIST K-233. These binary curves are
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discouraged for new systems.
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.. class:: SECT163K1
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.. versionadded:: 0.5
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SECG curve ``sect163k1``. Also called NIST K-163. These binary curves are
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discouraged for new systems.
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.. class:: SECT571R1
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.. versionadded:: 0.5
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SECG curve ``sect571r1``. Also called NIST B-571. These binary curves are
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discouraged for new systems.
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.. class:: SECT409R1
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.. versionadded:: 0.5
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SECG curve ``sect409r1``. Also called NIST B-409. These binary curves are
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discouraged for new systems.
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.. class:: SECT283R1
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.. versionadded:: 0.5
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SECG curve ``sect283r1``. Also called NIST B-283. These binary curves are
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discouraged for new systems.
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.. class:: SECT233R1
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.. versionadded:: 0.5
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SECG curve ``sect233r1``. Also called NIST B-233. These binary curves are
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discouraged for new systems.
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.. class:: SECT163R2
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.. versionadded:: 0.5
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SECG curve ``sect163r2``. Also called NIST B-163. These binary curves are
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discouraged for new systems.
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Key Interfaces
481400
~~~~~~~~~~~~~~
@@ -832,66 +751,6 @@ Elliptic Curve Object Identifiers
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833752
Corresponds to the dotted string ``"1.3.36.3.3.2.8.1.1.13"``.
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835-
.. attribute:: SECT163K1
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.. versionadded:: 2.5
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Corresponds to the dotted string ``"1.3.132.0.1"``.
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.. attribute:: SECT163R2
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.. versionadded:: 2.5
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Corresponds to the dotted string ``"1.3.132.0.15"``.
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.. attribute:: SECT233K1
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.. versionadded:: 2.5
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Corresponds to the dotted string ``"1.3.132.0.26"``.
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.. attribute:: SECT233R1
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.. versionadded:: 2.5
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Corresponds to the dotted string ``"1.3.132.0.27"``.
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.. attribute:: SECT283K1
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.. versionadded:: 2.5
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Corresponds to the dotted string ``"1.3.132.0.16"``.
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.. attribute:: SECT283R1
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.. versionadded:: 2.5
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Corresponds to the dotted string ``"1.3.132.0.17"``.
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.. attribute:: SECT409K1
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.. versionadded:: 2.5
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Corresponds to the dotted string ``"1.3.132.0.36"``.
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.. attribute:: SECT409R1
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.. versionadded:: 2.5
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Corresponds to the dotted string ``"1.3.132.0.37"``.
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.. attribute:: SECT571K1
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.. versionadded:: 2.5
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Corresponds to the dotted string ``"1.3.132.0.38"``.
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.. attribute:: SECT571R1
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.. versionadded:: 2.5
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Corresponds to the dotted string ``"1.3.132.0.39"``.
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895754
.. function:: get_curve_for_oid(oid)
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.. versionadded:: 2.6

‎src/cryptography/hazmat/primitives/asymmetric/ec.py‎

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@@ -25,16 +25,6 @@ class EllipticCurveOID:
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BRAINPOOLP256R1 = ObjectIdentifier("1.3.36.3.3.2.8.1.1.7")
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BRAINPOOLP384R1 = ObjectIdentifier("1.3.36.3.3.2.8.1.1.11")
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BRAINPOOLP512R1 = ObjectIdentifier("1.3.36.3.3.2.8.1.1.13")
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SECT163K1 = ObjectIdentifier("1.3.132.0.1")
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SECT163R2 = ObjectIdentifier("1.3.132.0.15")
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SECT233K1 = ObjectIdentifier("1.3.132.0.26")
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SECT233R1 = ObjectIdentifier("1.3.132.0.27")
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SECT283K1 = ObjectIdentifier("1.3.132.0.16")
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SECT283R1 = ObjectIdentifier("1.3.132.0.17")
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SECT409K1 = ObjectIdentifier("1.3.132.0.36")
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SECT409R1 = ObjectIdentifier("1.3.132.0.37")
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SECT571K1 = ObjectIdentifier("1.3.132.0.38")
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SECT571R1 = ObjectIdentifier("1.3.132.0.39")
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class EllipticCurve(metaclass=abc.ABCMeta):
@@ -227,66 +217,6 @@ def __deepcopy__(self, memo: dict) -> EllipticCurvePublicKey:
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EllipticCurvePublicNumbers = rust_openssl.ec.EllipticCurvePublicNumbers
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class SECT571R1(EllipticCurve):
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name = "sect571r1"
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key_size = 570
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group_order = 0x3FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFE661CE18FF55987308059B186823851EC7DD9CA1161DE93D5174D66E8382E9BB2FE84E47 # noqa: E501
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class SECT409R1(EllipticCurve):
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name = "sect409r1"
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key_size = 409
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group_order = 0x10000000000000000000000000000000000000000000000000001E2AAD6A612F33307BE5FA47C3C9E052F838164CD37D9A21173 # noqa: E501
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class SECT283R1(EllipticCurve):
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name = "sect283r1"
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key_size = 282
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group_order = 0x3FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEF90399660FC938A90165B042A7CEFADB307 # noqa: E501
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class SECT233R1(EllipticCurve):
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name = "sect233r1"
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key_size = 233
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group_order = 0x1000000000000000000000000000013E974E72F8A6922031D2603CFE0D7
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class SECT163R2(EllipticCurve):
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name = "sect163r2"
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key_size = 163
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group_order = 0x40000000000000000000292FE77E70C12A4234C33
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class SECT571K1(EllipticCurve):
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name = "sect571k1"
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key_size = 570
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group_order = 0x20000000000000000000000000000000000000000000000000000000000000000000000131850E1F19A63E4B391A8DB917F4138B630D84BE5D639381E91DEB45CFE778F637C1001 # noqa: E501
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class SECT409K1(EllipticCurve):
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name = "sect409k1"
268-
key_size = 407
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group_order = 0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFE5F83B2D4EA20400EC4557D5ED3E3E7CA5B4B5C83B8E01E5FCF # noqa: E501
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class SECT283K1(EllipticCurve):
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name = "sect283k1"
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key_size = 281
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group_order = 0x1FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFE9AE2ED07577265DFF7F94451E061E163C61 # noqa: E501
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class SECT233K1(EllipticCurve):
279-
name = "sect233k1"
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key_size = 232
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group_order = 0x8000000000000000000000000000069D5BB915BCD46EFB1AD5F173ABDF
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class SECT163K1(EllipticCurve):
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name = "sect163k1"
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key_size = 163
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group_order = 0x4000000000000000000020108A2E0CC0D99F8A5EF
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290220
class SECP521R1(EllipticCurve):
291221
name = "secp521r1"
292222
key_size = 521
@@ -356,16 +286,6 @@ class BrainpoolP512R1(EllipticCurve):
356286
"secp384r1": SECP384R1(),
357287
"secp521r1": SECP521R1(),
358288
"secp256k1": SECP256K1(),
359-
"sect163k1": SECT163K1(),
360-
"sect233k1": SECT233K1(),
361-
"sect283k1": SECT283K1(),
362-
"sect409k1": SECT409K1(),
363-
"sect571k1": SECT571K1(),
364-
"sect163r2": SECT163R2(),
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"sect233r1": SECT233R1(),
366-
"sect283r1": SECT283R1(),
367-
"sect409r1": SECT409R1(),
368-
"sect571r1": SECT571R1(),
369289
"brainpoolP256r1": BrainpoolP256R1(),
370290
"brainpoolP384r1": BrainpoolP384R1(),
371291
"brainpoolP512r1": BrainpoolP512R1(),
@@ -436,16 +356,6 @@ class ECDH:
436356
EllipticCurveOID.BRAINPOOLP256R1: BrainpoolP256R1,
437357
EllipticCurveOID.BRAINPOOLP384R1: BrainpoolP384R1,
438358
EllipticCurveOID.BRAINPOOLP512R1: BrainpoolP512R1,
439-
EllipticCurveOID.SECT163K1: SECT163K1,
440-
EllipticCurveOID.SECT163R2: SECT163R2,
441-
EllipticCurveOID.SECT233K1: SECT233K1,
442-
EllipticCurveOID.SECT233R1: SECT233R1,
443-
EllipticCurveOID.SECT283K1: SECT283K1,
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EllipticCurveOID.SECT283R1: SECT283R1,
445-
EllipticCurveOID.SECT409K1: SECT409K1,
446-
EllipticCurveOID.SECT409R1: SECT409R1,
447-
EllipticCurveOID.SECT571K1: SECT571K1,
448-
EllipticCurveOID.SECT571R1: SECT571R1,
449359
}
450360

451361

‎src/rust/cryptography-key-parsing/src/ec.rs‎

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@@ -29,16 +29,6 @@ pub(crate) fn group_to_curve_oid(
2929
openssl::nid::Nid::SECP384R1 => Some(cryptography_x509::oid::EC_SECP384R1),
3030
openssl::nid::Nid::SECP521R1 => Some(cryptography_x509::oid::EC_SECP521R1),
3131
openssl::nid::Nid::SECP256K1 => Some(cryptography_x509::oid::EC_SECP256K1),
32-
openssl::nid::Nid::SECT233R1 => Some(cryptography_x509::oid::EC_SECT233R1),
33-
openssl::nid::Nid::SECT283R1 => Some(cryptography_x509::oid::EC_SECT283R1),
34-
openssl::nid::Nid::SECT409R1 => Some(cryptography_x509::oid::EC_SECT409R1),
35-
openssl::nid::Nid::SECT571R1 => Some(cryptography_x509::oid::EC_SECT571R1),
36-
openssl::nid::Nid::SECT163R2 => Some(cryptography_x509::oid::EC_SECT163R2),
37-
openssl::nid::Nid::SECT163K1 => Some(cryptography_x509::oid::EC_SECT163K1),
38-
openssl::nid::Nid::SECT233K1 => Some(cryptography_x509::oid::EC_SECT233K1),
39-
openssl::nid::Nid::SECT283K1 => Some(cryptography_x509::oid::EC_SECT283K1),
40-
openssl::nid::Nid::SECT409K1 => Some(cryptography_x509::oid::EC_SECT409K1),
41-
openssl::nid::Nid::SECT571K1 => Some(cryptography_x509::oid::EC_SECT571K1),
4232
#[cfg(not(any(CRYPTOGRAPHY_IS_BORINGSSL, CRYPTOGRAPHY_IS_AWSLC)))]
4333
openssl::nid::Nid::BRAINPOOL_P256R1 => Some(cryptography_x509::oid::EC_BRAINPOOLP256R1),
4434
#[cfg(not(any(CRYPTOGRAPHY_IS_BORINGSSL, CRYPTOGRAPHY_IS_AWSLC)))]
@@ -63,19 +53,6 @@ pub(crate) fn ec_params_to_group(
6353

6454
&cryptography_x509::oid::EC_SECP256K1 => openssl::nid::Nid::SECP256K1,
6555

66-
&cryptography_x509::oid::EC_SECT233R1 => openssl::nid::Nid::SECT233R1,
67-
&cryptography_x509::oid::EC_SECT283R1 => openssl::nid::Nid::SECT283R1,
68-
&cryptography_x509::oid::EC_SECT409R1 => openssl::nid::Nid::SECT409R1,
69-
&cryptography_x509::oid::EC_SECT571R1 => openssl::nid::Nid::SECT571R1,
70-
71-
&cryptography_x509::oid::EC_SECT163R2 => openssl::nid::Nid::SECT163R2,
72-
73-
&cryptography_x509::oid::EC_SECT163K1 => openssl::nid::Nid::SECT163K1,
74-
&cryptography_x509::oid::EC_SECT233K1 => openssl::nid::Nid::SECT233K1,
75-
&cryptography_x509::oid::EC_SECT283K1 => openssl::nid::Nid::SECT283K1,
76-
&cryptography_x509::oid::EC_SECT409K1 => openssl::nid::Nid::SECT409K1,
77-
&cryptography_x509::oid::EC_SECT571K1 => openssl::nid::Nid::SECT571K1,
78-
7956
#[cfg(not(any(CRYPTOGRAPHY_IS_BORINGSSL, CRYPTOGRAPHY_IS_AWSLC)))]
8057
&cryptography_x509::oid::EC_BRAINPOOLP256R1 => openssl::nid::Nid::BRAINPOOL_P256R1,
8158
#[cfg(not(any(CRYPTOGRAPHY_IS_BORINGSSL, CRYPTOGRAPHY_IS_AWSLC)))]

‎src/rust/cryptography-x509/src/oid.rs‎

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Original file line numberDiff line numberDiff line change
@@ -58,19 +58,6 @@ pub const EC_SECP521R1: asn1::ObjectIdentifier = asn1::oid!(1, 3, 132, 0, 35);
5858

5959
pub const EC_SECP256K1: asn1::ObjectIdentifier = asn1::oid!(1, 3, 132, 0, 10);
6060

61-
pub const EC_SECT233R1: asn1::ObjectIdentifier = asn1::oid!(1, 3, 132, 0, 27);
62-
pub const EC_SECT283R1: asn1::ObjectIdentifier = asn1::oid!(1, 3, 132, 0, 17);
63-
pub const EC_SECT409R1: asn1::ObjectIdentifier = asn1::oid!(1, 3, 132, 0, 37);
64-
pub const EC_SECT571R1: asn1::ObjectIdentifier = asn1::oid!(1, 3, 132, 0, 39);
65-
66-
pub const EC_SECT163R2: asn1::ObjectIdentifier = asn1::oid!(1, 3, 132, 0, 15);
67-
68-
pub const EC_SECT163K1: asn1::ObjectIdentifier = asn1::oid!(1, 3, 132, 0, 1);
69-
pub const EC_SECT233K1: asn1::ObjectIdentifier = asn1::oid!(1, 3, 132, 0, 26);
70-
pub const EC_SECT283K1: asn1::ObjectIdentifier = asn1::oid!(1, 3, 132, 0, 16);
71-
pub const EC_SECT409K1: asn1::ObjectIdentifier = asn1::oid!(1, 3, 132, 0, 36);
72-
pub const EC_SECT571K1: asn1::ObjectIdentifier = asn1::oid!(1, 3, 132, 0, 38);
73-
7461
pub const EC_BRAINPOOLP256R1: asn1::ObjectIdentifier = asn1::oid!(1, 3, 36, 3, 3, 2, 8, 1, 1, 7);
7562
pub const EC_BRAINPOOLP384R1: asn1::ObjectIdentifier = asn1::oid!(1, 3, 36, 3, 3, 2, 8, 1, 1, 11);
7663
pub const EC_BRAINPOOLP512R1: asn1::ObjectIdentifier = asn1::oid!(1, 3, 36, 3, 3, 2, 8, 1, 1, 13);

‎src/rust/src/backend/ec.rs‎

Lines changed: 12 additions & 17 deletions
Original file line numberDiff line numberDiff line change
@@ -47,19 +47,6 @@ fn curve_from_py_curve(
4747

4848
"secp256k1" => openssl::nid::Nid::SECP256K1,
4949

50-
"sect233r1" => openssl::nid::Nid::SECT233R1,
51-
"sect283r1" => openssl::nid::Nid::SECT283R1,
52-
"sect409r1" => openssl::nid::Nid::SECT409R1,
53-
"sect571r1" => openssl::nid::Nid::SECT571R1,
54-
55-
"sect163r2" => openssl::nid::Nid::SECT163R2,
56-
57-
"sect163k1" => openssl::nid::Nid::SECT163K1,
58-
"sect233k1" => openssl::nid::Nid::SECT233K1,
59-
"sect283k1" => openssl::nid::Nid::SECT283K1,
60-
"sect409k1" => openssl::nid::Nid::SECT409K1,
61-
"sect571k1" => openssl::nid::Nid::SECT571K1,
62-
6350
#[cfg(not(any(CRYPTOGRAPHY_IS_BORINGSSL, CRYPTOGRAPHY_IS_AWSLC)))]
6451
"brainpoolP256r1" => openssl::nid::Nid::BRAINPOOL_P256R1,
6552
#[cfg(not(any(CRYPTOGRAPHY_IS_BORINGSSL, CRYPTOGRAPHY_IS_AWSLC)))]
@@ -249,9 +236,11 @@ impl ECPrivateKey {
249236

250237
let len = deriver.len()?;
251238
Ok(pyo3::types::PyBytes::new_with(py, len, |b| {
252-
let n = py.detach(|| deriver.derive(b)).map_err(|_| {
253-
pyo3::exceptions::PyValueError::new_err("Error computing shared key.")
254-
})?;
239+
// Previously it was possible to have derive return an error
240+
// if a public key was in a subgroup. Now that we only
241+
// support cofactor 1 curves this should be unreachable
242+
// so we unwrap.
243+
let n = py.detach(|| deriver.derive(b)).unwrap();
255244
assert_eq!(n, b.len());
256245
Ok(())
257246
})?)
@@ -389,7 +378,13 @@ impl ECPublicKey {
389378
) -> CryptographyResult<ECPublicKey> {
390379
let ec = pkey.ec_key()?;
391380
check_key_infinity(&ec)?;
392-
381+
let mut bn_ctx = openssl::bn::BigNumContext::new()?;
382+
let mut cofactor = openssl::bn::BigNum::new()?;
383+
ec.group().cofactor(&mut cofactor, &mut bn_ctx)?;
384+
let one = openssl::bn::BigNum::from_u32(1)?;
385+
// We only support curves with a cofactor of 1.
386+
// Any change here requires more careful key checking
387+
assert_eq!(cofactor, one, "cofactor must be 1");
393388
Ok(ECPublicKey { pkey, curve })
394389
}
395390
}

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