diff --git a/python-cryptography.spec b/python-cryptography.spec
index 2014eb6..affdc2d 100644
--- a/python-cryptography.spec
+++ b/python-cryptography.spec
@@ -7,7 +7,7 @@
 
 Name:           python-%{srcname}
 Version:        3.4.1
-Release:        1%{?dist}
+Release:        2%{?dist}
 Summary:        PyCA's cryptography library
 
 License:        ASL 2.0 or BSD
@@ -24,9 +24,6 @@ BuildRequires:  openssl-devel
 BuildRequires:  gcc
 BuildRequires:  gnupg2
 BuildRequires:  rust-packaging
-BuildRequires:  rust-pyo3+default-devel >= %{pyo3_version}
-BuildRequires:  rust-pyo3+extension-module-devel >= %{pyo3_version}
-BuildRequires:  rust-pyo3+abi3-py36-devel >= %{pyo3_version}
 
 BuildRequires:  python%{python3_pkgversion}-cffi >= 1.7
 BuildRequires:  python%{python3_pkgversion}-devel
@@ -67,8 +64,12 @@ recipes to Python developers.
 %cargo_prep
 rm -f src/rust/Cargo.lock
 
+%generate_buildrequires
+cd src/rust
+%cargo_generate_buildrequires
+cd ../..
+
 %build
-export CARGO_NET_OFFLINE=true
 %py3_build
 
 %install
@@ -91,6 +92,10 @@ PYTHONPATH=%{buildroot}%{python3_sitearch} %{__python3} -m pytest -k "not (test_
 %{python3_sitearch}/%{srcname}-%{version}-py*.egg-info
 
 %changelog
+* Mon Feb 08 2021 Fabio Valentini <decathorpe@gmail.com> - 3.4.1-2
+- Use dynamically generated BuildRequires for PyO3 Rust module.
+- Drop unnecessary CARGO_NET_OFFLINE environment variable.
+
 * Sun Feb 07 2021 Christian Heimes <cheimes@redhat.com> - 3.4.1-1
 - Update to 3.4.1 (#1925953)