CERTivity is a powerful multi-platform visual tool for creating, managing, and handling different key store types (such as JKS, JCEKS, PKCS12, the Bouncy Castle types BKS and UBER, and Windows Native), public, private and secret keys in different formats (PKCS, OpenSSL, RSA/DSA, etc.), certificates (version 1 and 3), and certificates chains. It allows you to import and export keys, key pairs and certificates, manage certificate extensions, extend the validity period for self-signed certificates, test certificates, obtain revocation status, convert from one key store type to another, and much more.
A complete IPsec and IKEv2/IKEv1 implementation for Linux 2.4 and 2.6 kernels.