- Improve security by removing support for modp1024 (DH group 2),
which is less secure and no longer enabled in Libreswan by default.
- The native VPN client on Android devices uses modp1024 for the
IPsec/L2TP and IPsec/XAuth ("Cisco IPsec") modes. After this change,
Android users should instead connect using IKEv2 mode (recommended).