test/test_pkey_rsa: fix test failure with OpenSSL 1.1.1

OpenSSL 1.1.1 raised the minimum size for RSA keys to 512 bits.

Author: rhenium

test/test_pkey_rsa.rb

@@ -60,6 +60,13 @@ def test_new_with_exponent
     end
   end
 
+  def test_generate
+    key = OpenSSL::PKey::RSA.generate(512, 17)
+    assert_equal 512, key.n.num_bits
+    assert_equal 17, key.e
+    assert_not_nil key.d
+  end
+
   def test_new_break
     assert_nil(OpenSSL::PKey::RSA.new(1024) { break })
     assert_raise(RuntimeError) do
@@ -256,7 +263,7 @@ def test_pem_passwd
   end
 
   def test_dup
-    key = OpenSSL::PKey::RSA.generate(256, 17)
+    key = Fixtures.pkey("rsa1024")
     key2 = key.dup
     assert_equal key.params, key2.params
     key2.set_key(key2.n, 3, key2.d)