move hashes, hmac, and kdf to declarative

src/rust/src/backend/hashes.rs

@@ -2,7 +2,7 @@
 // 2.0, and the BSD License. See the LICENSE file in the root of this repository
 // for complete details.
 
-use pyo3::types::{PyAnyMethods, PyModuleMethods};
+use pyo3::types::PyAnyMethods;
 use pyo3::IntoPy;
 use std::borrow::Cow;
 
@@ -138,11 +138,8 @@ impl Hash {
     }
 }
 
-pub(crate) fn create_module(
-    py: pyo3::Python<'_>,
-) -> pyo3::PyResult<pyo3::Bound<'_, pyo3::types::PyModule>> {
-    let m = pyo3::types::PyModule::new_bound(py, "hashes")?;
-    m.add_class::<Hash>()?;
-
-    Ok(m)
+#[pyo3::pymodule]
+pub(crate) mod hashes {
+    #[pymodule_export]
+    use super::Hash;
 }

src/rust/src/backend/hmac.rs

@@ -6,7 +6,7 @@ use crate::backend::hashes::{already_finalized_error, message_digest_from_algori
 use crate::buf::CffiBuf;
 use crate::error::{CryptographyError, CryptographyResult};
 use crate::exceptions;
-use pyo3::types::{PyBytesMethods, PyModuleMethods};
+use pyo3::types::PyBytesMethods;
 
 #[pyo3::pyclass(
     module = "cryptography.hazmat.bindings._rust.openssl.hmac",
@@ -106,11 +106,8 @@ impl Hmac {
     }
 }
 
-pub(crate) fn create_module(
-    py: pyo3::Python<'_>,
-) -> pyo3::PyResult<pyo3::Bound<'_, pyo3::types::PyModule>> {
-    let m = pyo3::types::PyModule::new_bound(py, "hmac")?;
-    m.add_class::<Hmac>()?;
-
-    Ok(m)
+#[pyo3::pymodule]
+pub(crate) mod hmac {
+    #[pymodule_export]
+    use super::Hmac;
 }

src/rust/src/backend/kdf.rs

@@ -5,7 +5,6 @@
 use crate::backend::hashes;
 use crate::buf::CffiBuf;
 use crate::error::CryptographyResult;
-use pyo3::types::PyModuleMethods;
 
 #[pyo3::pyfunction]
 pub(crate) fn derive_pbkdf2_hmac<'p>(
@@ -49,14 +48,11 @@ fn derive_scrypt<'p>(
     })?)
 }
 
-pub(crate) fn create_module(
-    py: pyo3::Python<'_>,
-) -> pyo3::PyResult<pyo3::Bound<'_, pyo3::types::PyModule>> {
-    let m = pyo3::types::PyModule::new_bound(py, "kdf")?;
-
-    m.add_function(pyo3::wrap_pyfunction_bound!(derive_pbkdf2_hmac, &m)?)?;
+#[pyo3::pymodule]
+pub(crate) mod kdf {
+    #[pymodule_export]
+    use super::derive_pbkdf2_hmac;
     #[cfg(not(CRYPTOGRAPHY_IS_LIBRESSL))]
-    m.add_function(pyo3::wrap_pyfunction_bound!(derive_scrypt, &m)?)?;
-
-    Ok(m)
+    #[pymodule_export]
+    use super::derive_scrypt;
 }

src/rust/src/backend/mod.rs

@@ -43,9 +43,6 @@ pub(crate) fn add_to_module(module: &pyo3::Bound<'_, pyo3::types::PyModule>) ->
 
     module.add_submodule(&poly1305::create_module(module.py())?)?;
 
-    module.add_submodule(&hashes::create_module(module.py())?)?;
-    module.add_submodule(&hmac::create_module(module.py())?)?;
-    module.add_submodule(&kdf::create_module(module.py())?)?;
     module.add_submodule(&rsa::create_module(module.py())?)?;
 
     Ok(())

src/rust/src/lib.rs

@@ -148,6 +148,12 @@ mod _rust {
         #[pymodule_export]
         use super::super::{is_fips_enabled, openssl_version, openssl_version_text};
         #[pymodule_export]
+        use crate::backend::hashes::hashes;
+        #[pymodule_export]
+        use crate::backend::hmac::hmac;
+        #[pymodule_export]
+        use crate::backend::kdf::kdf;
+        #[pymodule_export]
         use crate::backend::keys::keys;
         #[pymodule_export]
         use crate::error::{capture_error_stack, raise_openssl_error, OpenSSLError};