From 56255de6b2d1a2d2e502b0275231ca81907f33f1 Mon Sep 17 00:00:00 2001 From: Paul Kehrer Date: Wed, 24 Jan 2024 19:02:37 -0700 Subject: [PATCH] allow SPKI RSA keys to be parsed even if they have an incorrect delimiter (#10248) (#10251) * allow SPKI RSA keys to be parsed even if they have an incorrect delimiter This allows RSA SPKI keys (typically delimited with PUBLIC KEY) to be parsed even if they are using the RSA PUBLIC KEY delimiter. * formatting * use original error if nothing parses, don't let it parse non-RSA --- docs/development/test-vectors.rst | 6 ++++++ src/rust/src/backend/keys.rs | 21 ++++++++++++++++++- tests/hazmat/primitives/test_serialization.py | 16 ++++++++++++++ .../ec_public_key_rsa_delimiter.pem | 4 ++++ .../rsa_wrong_delimiter_public_key.pem | 9 ++++++++ 5 files changed, 55 insertions(+), 1 deletion(-) create mode 100644 vectors/cryptography_vectors/asymmetric/PEM_Serialization/ec_public_key_rsa_delimiter.pem create mode 100644 vectors/cryptography_vectors/asymmetric/PEM_Serialization/rsa_wrong_delimiter_public_key.pem diff --git a/docs/development/test-vectors.rst b/docs/development/test-vectors.rst index 1255688840f3..0b1f238ffaa2 100644 --- a/docs/development/test-vectors.rst +++ b/docs/development/test-vectors.rst @@ -72,12 +72,18 @@ Custom asymmetric vectors * ``asymmetric/PEM_Serialization/ec_public_key.pem`` and ``asymmetric/DER_Serialization/ec_public_key.der``- Contains the public key corresponding to ``ec_private_key.pem``, generated using OpenSSL. +* ``asymmetric/PEM_Serialization/ec_public_key_rsa_delimiter.pem`` - Contains + the public key corresponding to ``ec_private_key.pem``, but with the wrong PEM + delimiter (``RSA PUBLIC KEY`` when it should be ``PUBLIC KEY``). * ``asymmetric/PEM_Serialization/rsa_private_key.pem`` - Contains an RSA 2048 bit key generated using OpenSSL, protected by the secret "123456" with DES3 encryption. * ``asymmetric/PEM_Serialization/rsa_public_key.pem`` and ``asymmetric/DER_Serialization/rsa_public_key.der``- Contains an RSA 2048 bit public generated using OpenSSL from ``rsa_private_key.pem``. +* ``asymmetric/PEM_Serialization/rsa_wrong_delimiter_public_key.pem`` - Contains + an RSA 2048 bit public key generated from ``rsa_private_key.pem``, but with + the wrong PEM delimiter (``RSA PUBLIC KEY`` when it should be ``PUBLIC KEY``). * ``asymmetric/PEM_Serialization/dsa_4096.pem`` - Contains a 4096-bit DSA private key generated using OpenSSL. * ``asymmetric/PEM_Serialization/dsaparam.pem`` - Contains 2048-bit DSA diff --git a/src/rust/src/backend/keys.rs b/src/rust/src/backend/keys.rs index bd3e8eb28e3b..ecdff5db6dcb 100644 --- a/src/rust/src/backend/keys.rs +++ b/src/rust/src/backend/keys.rs @@ -165,7 +165,26 @@ fn load_pem_public_key( let _ = backend; let p = pem::parse(data.as_bytes())?; let pkey = match p.tag() { - "RSA PUBLIC KEY" => cryptography_key_parsing::rsa::parse_pkcs1_public_key(p.contents())?, + "RSA PUBLIC KEY" => { + // We try to parse it as a PKCS1 first since that's the PEM delimiter, and if + // that fails we try to parse it as an SPKI. This is to match the permissiveness + // of OpenSSL, which doesn't care about the delimiter. + match cryptography_key_parsing::rsa::parse_pkcs1_public_key(p.contents()) { + Ok(pkey) => pkey, + Err(err) => { + let pkey = cryptography_key_parsing::spki::parse_public_key(p.contents()) + .map_err(|_| err)?; + if pkey.id() != openssl::pkey::Id::RSA { + return Err(CryptographyError::from( + pyo3::exceptions::PyValueError::new_err( + "Incorrect PEM delimiter for key type.", + ), + )); + } + pkey + } + } + } "PUBLIC KEY" => cryptography_key_parsing::spki::parse_public_key(p.contents())?, _ => return Err(CryptographyError::from(pem::PemError::MalformedFraming)), }; diff --git a/tests/hazmat/primitives/test_serialization.py b/tests/hazmat/primitives/test_serialization.py index 58693a4912d2..51fcc3563d8a 100644 --- a/tests/hazmat/primitives/test_serialization.py +++ b/tests/hazmat/primitives/test_serialization.py @@ -506,6 +506,11 @@ def test_load_pem_ec_private_key(self, key_path, password, backend): "asymmetric", "PEM_Serialization", "rsa_public_key.pem" ), os.path.join("asymmetric", "public", "PKCS1", "rsa.pub.pem"), + os.path.join( + "asymmetric", + "PEM_Serialization", + "rsa_wrong_delimiter_public_key.pem", + ), ], ) def test_load_pem_rsa_public_key(self, key_file, backend): @@ -520,6 +525,17 @@ def test_load_pem_rsa_public_key(self, key_file, backend): numbers = key.public_numbers() assert numbers.e == 65537 + def test_load_pem_public_fails_with_ec_key_with_rsa_delimiter(self): + with pytest.raises(ValueError): + load_vectors_from_file( + os.path.join( + "asymmetric", + "PEM_Serialization", + "ec_public_key_rsa_delimiter.pem", + ), + lambda pemfile: load_pem_public_key(pemfile.read().encode()), + ) + def test_load_priv_key_with_public_key_api_fails( self, rsa_key_2048, backend ): diff --git a/vectors/cryptography_vectors/asymmetric/PEM_Serialization/ec_public_key_rsa_delimiter.pem b/vectors/cryptography_vectors/asymmetric/PEM_Serialization/ec_public_key_rsa_delimiter.pem new file mode 100644 index 000000000000..565ece176bf5 --- /dev/null +++ b/vectors/cryptography_vectors/asymmetric/PEM_Serialization/ec_public_key_rsa_delimiter.pem @@ -0,0 +1,4 @@ +-----BEGIN RSA PUBLIC KEY----- +MFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAEJLzzbuz2tRnLFlOL+6bTX6giVavA +sc6NDFFT0IMCd2ibTTNUDDkFGsgq0cH5JYPg/6xUlMBFKrWYe3yQ4has9w== +-----END RSA PUBLIC KEY----- diff --git a/vectors/cryptography_vectors/asymmetric/PEM_Serialization/rsa_wrong_delimiter_public_key.pem b/vectors/cryptography_vectors/asymmetric/PEM_Serialization/rsa_wrong_delimiter_public_key.pem new file mode 100644 index 000000000000..78053b4e6ed9 --- /dev/null +++ b/vectors/cryptography_vectors/asymmetric/PEM_Serialization/rsa_wrong_delimiter_public_key.pem @@ -0,0 +1,9 @@ +-----BEGIN RSA PUBLIC KEY----- +MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAnR4AZ+tgWYql+S3MaTQ6 +zeIO1fKzFIoau9Q0zGuv/1oCAewXwxeDSSxw+/Z3GL1NpuuS9CpbR5EQ3d71bD0v +0G+Sf+mShSl0oljG7YqnNSPzKl+EQ3/KE+eEButcwas6KGof2BA4bFNCw/fPbuhk +u/d8sIIEgdzBMiGRMdW33uci3rsdOenMZQA7uWsM/q/pu85YLAVOxq6wlUCzP4FM +Tw/RKzayrPkn3Jfbqcy1aM2HDlFVx24vaN+RRbPSnVoQbo5EQYkUMXE8WmadSyHl +pXGRnWsJSV9AdGyDrbU+6tcFwcIwnW22jb/OJy8swHdqKGkuR1kQ0XqokK1yGKFZ +8wIDAQAB +-----END RSA PUBLIC KEY-----