add RSA private key generation restrictions to primitive layer

1 files changed, 9 insertions, 0 deletions

diff --git a/cryptography/hazmat/primitives/asymmetric/rsa.py b/cryptography/hazmat/primitives/asymmetric/rsa.py
index a9f57838..e3ad5f1d 100644
--- a/cryptography/hazmat/primitives/asymmetric/rsa.py
+++ b/cryptography/hazmat/primitives/asymmetric/rsa.py
@@ -187,6 +187,15 @@ class RSAPrivateKey(object):
                 _Reasons.BACKEND_MISSING_INTERFACE
             )
 
+        if public_exponent < 3:
+            raise ValueError("public_exponent must be >= 3.")
+
+        if public_exponent & 1 == 0:
+            raise ValueError("public_exponent must be odd.")
+
+        if key_size < 512:
+            raise ValueError("key_size must be at least 512-bits.")
+
         return backend.generate_rsa_private_key(public_exponent, key_size)
 
     def signer(self, padding, algorithm, backend):