SoftHSM is an implementation of a cryptographic store accessible through a PKCS#11 interface. You can use it to explore PKCS#11 without having a Hardware Security Module. It is being developed as a part of the OpenDNSSEC project. SoftHSM uses Botan for its cryptographic operations.
php_mt_seed finds possible seeds given the very first PHP mt_rand() output after possible seeding with mt_srand(). With advanced invocation modes, php_mt_seed is also able to match multiple, non-first, and/or inexact mt_rand() outputs to possible seed values. php_mt_seed is written in C with optional SIMD intrinsics (SSE4.1/AVX, XOP, AVX2, MIC) and OpenMP. On a modern quad-core CPU, it is able to search the full 32-bit seed space in one minute (or in just seven seconds on Xeon Phi).
The OpenCA OCSP Responder is an RFC 2560 compliant OCSPD responder. It can be used to verify the status of a certificate using OCSP clients (such as Mozilla/Netscape7). The Responder is actually included in the main OpenCA distribution package. It is also possible to install the daemon as a stand-alone application, in which case you will need a CRL (or access to an LDAP server where the CRL can be obtained).
passwdqc is a password/passphrase strength checking and policy enforcement tool set, including an optional PAM module (pam_passwdqc), command-line programs (pwqcheck and pwqgen), and a library (libpasswdqc). On systems with PAM, pam_passwdqc is normally invoked on password changes by programs such as passwd(1). It is capable of checking password or passphrase strength, enforcing a policy, and offering randomly-generated passphrases, with all of these features being optional and easily (re-)configurable. pwqcheck and pwqgen are standalone password/passphrase strength checking and random passphrase generator programs, respectively, and are usable from scripts. libpasswdqc is the underlying library, which may also be used from third-party programs.
Botan is a crypto library written in C++. It provides a variety of cryptographic algorithms, including common ones such as AES, MD5, SHA, HMAC, RSA, Diffie-Hellman, DSA, and ECDSA, as well as many others that are more obscure or specialized. It also offers SSL/TLS (client and server), X.509v3 certificates and CRLs, and PKCS #10 certificate requests. A message processing system that uses a filter/pipeline metaphor allows for many common cryptographic tasks to be completed with just a few lines of code. Assembly and SIMD optimizations for common CPUs offers speedups for critical algorithms like AES and SHA-1.
XCA is an interface for managing RSA and DSA keys, certificates, certificate signing requests, revocation lists and templates. It uses the OpenSSL and Qt4 libraries. Certificates and requests can be created and signed and many x509v3 extensions can be added. XCA supports multiple root and intermediate Certificate authorities. The CAs can be used to create CRLs and extend certificates. The following file-formats are supported: PEM, DER, PKCS#7, PKCS#8, PKCS#10, PKCS#12, and SPKAC.