rename get_null_for_ecb to get_iv_for_ecb per alex's comments
diff --git a/cryptography/bindings/openssl/api.py b/cryptography/bindings/openssl/api.py
index 02957d7..fd54a8f 100644
--- a/cryptography/bindings/openssl/api.py
+++ b/cryptography/bindings/openssl/api.py
@@ -86,7 +86,7 @@
         self._lib.EVP_CIPHER_CTX_set_padding(ctx, 0)
         return ctx
 
-    def get_null_for_ecb(self):
+    def get_iv_for_ecb(self):
         return self._ffi.NULL
 
     def update_encrypt_context(self, ctx, plaintext):
diff --git a/cryptography/primitives/block/modes.py b/cryptography/primitives/block/modes.py
index 8214143..e4fc886 100644
--- a/cryptography/primitives/block/modes.py
+++ b/cryptography/primitives/block/modes.py
@@ -29,4 +29,4 @@
     name = "ECB"
 
     def get_iv_or_nonce(self, api):
-        return api.get_null_for_ecb()
+        return api.get_iv_for_ecb()
diff --git a/tests/bindings/test_openssl.py b/tests/bindings/test_openssl.py
index c5927b7..f25236c 100644
--- a/tests/bindings/test_openssl.py
+++ b/tests/bindings/test_openssl.py
@@ -29,5 +29,5 @@
         """
         assert api.openssl_version_text().startswith("OpenSSL")
 
-    def test_get_null_for_ecb(self):
-        assert api.get_null_for_ecb() == api._ffi.NULL
+    def test_get_iv_for_ecb(self):
+        assert api.get_iv_for_ecb() == api._ffi.NULL