diff options
| -rw-r--r-- | cryptography/hazmat/backends/openssl/backend.py | 14 | ||||
| -rw-r--r-- | tests/hazmat/primitives/test_rsa.py | 63 | ||||
| -rw-r--r-- | tests/hazmat/primitives/utils.py | 32 |
3 files changed, 47 insertions, 62 deletions
diff --git a/cryptography/hazmat/backends/openssl/backend.py b/cryptography/hazmat/backends/openssl/backend.py index e3f421a5..d2744cf3 100644 --- a/cryptography/hazmat/backends/openssl/backend.py +++ b/cryptography/hazmat/backends/openssl/backend.py @@ -734,7 +734,8 @@ class _RSASignatureContext(object): # PSS signature length (salt length is checked later) key_size_bytes = int(math.ceil(private_key.key_size / 8.0)) if key_size_bytes - algorithm.digest_size - 2 < 0: - raise ValueError("Digest too large for key size.") + raise ValueError("Digest too large for key size. Use a larger " + "key.") if not self._backend.mgf1_hash_supported(padding._mgf._algorithm): raise UnsupportedHash( @@ -830,7 +831,8 @@ class _RSASignatureContext(object): assert errors[0].lib == self._backend._lib.ERR_LIB_RSA assert (errors[0].reason == self._backend._lib.RSA_R_DATA_TOO_LARGE_FOR_KEY_SIZE) - raise ValueError("Salt length too long for key size") + raise ValueError("Salt length too long for key size. Try using " + "MAX_LENGTH instead.") return self._backend._ffi.buffer(buf)[:] @@ -872,7 +874,8 @@ class _RSASignatureContext(object): assert errors[0].lib == self._backend._lib.ERR_LIB_RSA assert (errors[0].reason == self._backend._lib.RSA_R_DATA_TOO_LARGE_FOR_KEY_SIZE) - raise ValueError("Salt length too long for key size") + raise ValueError("Salt length too long for key size. Try using " + "MAX_LENGTH instead.") sig_buf = self._backend._ffi.new("char[]", pkey_size) sig_len = self._backend._lib.RSA_private_encrypt( @@ -913,7 +916,10 @@ class _RSAVerificationContext(object): # PSS signature length (salt length is checked later) key_size_bytes = int(math.ceil(public_key.key_size / 8.0)) if key_size_bytes - algorithm.digest_size - 2 < 0: - raise ValueError("Digest too large for key size.") + raise ValueError( + "Digest too large for key size. Check that you have the " + "correct key and digest algorithm." + ) if not self._backend.mgf1_hash_supported(padding._mgf._algorithm): raise UnsupportedHash( diff --git a/tests/hazmat/primitives/test_rsa.py b/tests/hazmat/primitives/test_rsa.py index 957e70a3..eb7e1e60 100644 --- a/tests/hazmat/primitives/test_rsa.py +++ b/tests/hazmat/primitives/test_rsa.py @@ -28,7 +28,7 @@ from cryptography.exceptions import ( from cryptography.hazmat.primitives import hashes, interfaces from cryptography.hazmat.primitives.asymmetric import padding, rsa -from .utils import generate_rsa_verification_test, rsa_pss_signing_test +from .utils import generate_rsa_verification_test from ...utils import ( load_pkcs1_vectors, load_rsa_nist_vectors, load_vectors_from_file ) @@ -483,33 +483,42 @@ class TestRSASignature(object): verifier.update(binascii.unhexlify(example["message"])) verifier.verify() - @pytest.mark.supported( - only_if=lambda backend: backend.mgf1_hash_supported(hashes.SHA224()), - skip_message="Does not support SHA224 with MGF1." - ) - def test_pss_signing_sha224(self, backend): - rsa_pss_signing_test(backend, hashes.SHA224()) - - @pytest.mark.supported( - only_if=lambda backend: backend.mgf1_hash_supported(hashes.SHA256()), - skip_message="Does not support SHA256 with MGF1." - ) - def test_pss_signing_sha256(self, backend): - rsa_pss_signing_test(backend, hashes.SHA256()) - - @pytest.mark.supported( - only_if=lambda backend: backend.mgf1_hash_supported(hashes.SHA384()), - skip_message="Does not support SHA384 with MGF1." - ) - def test_pss_signing_sha384(self, backend): - rsa_pss_signing_test(backend, hashes.SHA384()) - - @pytest.mark.supported( - only_if=lambda backend: backend.mgf1_hash_supported(hashes.SHA512()), - skip_message="Does not support SHA512 with MGF1." + @pytest.mark.parametrize( + "hash_alg", + [hashes.SHA224(), hashes.SHA256(), hashes.SHA384(), hashes.SHA512()] ) - def test_pss_signing_sha512(self, backend): - rsa_pss_signing_test(backend, hashes.SHA512()) + def test_pss_signing_sha2(self, hash_alg, backend): + if not backend.mgf1_hash_supported(hash_alg): + pytest.skip( + "Does not support {0} with MGF1.".format(hash_alg.name) + ) + private_key = rsa.RSAPrivateKey.generate( + public_exponent=65537, + key_size=768, + backend=backend + ) + public_key = private_key.public_key() + pss = padding.PSS( + mgf=padding.MGF1( + algorithm=hash_alg, + salt_length=padding.MGF1.MAX_LENGTH + ) + ) + signer = private_key.signer( + pss, + hash_alg, + backend + ) + signer.update(b"testing signature") + signature = signer.finalize() + verifier = public_key.verifier( + signature, + pss, + hash_alg, + backend + ) + verifier.update(b"testing signature") + verifier.verify() @pytest.mark.supported( only_if=lambda backend: backend.hash_supported(hashes.SHA512()), diff --git a/tests/hazmat/primitives/utils.py b/tests/hazmat/primitives/utils.py index 76212daa..2e838474 100644 --- a/tests/hazmat/primitives/utils.py +++ b/tests/hazmat/primitives/utils.py @@ -24,7 +24,7 @@ from cryptography.exceptions import ( NotYetFinalized ) from cryptography.hazmat.primitives import hashes, hmac -from cryptography.hazmat.primitives.asymmetric import padding, rsa +from cryptography.hazmat.primitives.asymmetric import rsa from cryptography.hazmat.primitives.ciphers import Cipher from cryptography.hazmat.primitives.kdf.hkdf import HKDF from cryptography.hazmat.primitives.kdf.pbkdf2 import PBKDF2HMAC @@ -406,33 +406,3 @@ def rsa_verification_test(backend, params, hash_alg, pad_factory): verifier.verify() else: verifier.verify() - - -def rsa_pss_signing_test(backend, hash_alg): - private_key = rsa.RSAPrivateKey.generate( - public_exponent=65537, - key_size=768, - backend=backend - ) - public_key = private_key.public_key() - pss = padding.PSS( - mgf=padding.MGF1( - algorithm=hash_alg, - salt_length=padding.MGF1.MAX_LENGTH - ) - ) - signer = private_key.signer( - pss, - hash_alg, - backend - ) - signer.update(b"testing signature") - signature = signer.finalize() - verifier = public_key.verifier( - signature, - pss, - hash_alg, - backend - ) - verifier.update(b"testing signature") - verifier.verify() |