Open Source C Security Software

libsodium is a modern, portable, and easy-to-use cryptographic library that serves as an API-compatible fork of NaCl. Consistent behavior and formats across supported platforms. It enhances the original design with build and portability improvements, making it widely deployable across platforms for secure encryption, signatures, hashing, and key derivation. Digital signature creation and verification support. Adds extended cryptographic primitives like BLAKE2 and ChaCha20-Poly1305 beyond NaCl.

Shadowsocks-libev is a lightweight secured SOCKS5 proxy for embedded devices and low-end boxes. Shadowsocks-libev is written in pure C and depends on libev. It's designed to be a lightweight implementation of shadowsocks protocol, in order to keep the resource usage as low as possible. Snap is the recommended way to install the latest binaries. You can build shadowsocks-libev and all its dependencies by script. The latest shadowsocks-libev has provided a redir mode. You can configure your Linux-based box or router to proxy all TCP traffic transparently, which is handy if you use an OpenWRT-powered router. Although shadowsocks-libev can handle thousands of concurrent connections nicely, we still recommend setting up your server's firewall rules to limit connections from each user. We strongly encourage you to install shadowsocks-libev from jessie-backports-sloppy.

The wolfSSL embedded SSL library (formerly CyaSSL) is a lightweight, portable, C-language-based SSL/TLS library targeted at IoT, embedded, and RTOS environments primarily because of its size, speed, and feature set. It works seamlessly in desktop, enterprise, and cloud environments as well. wolfSSL supports industry standards up to the current TLS 1.2 and DTLS 1.2, is up to 20 times smaller than OpenSSL, offers a simple API, an OpenSSL compatibility layer, OCSP and CRL support, is backed by the robust wolfCrypt cryptography library, and much more. wolfSSL relies on the FIPS 140-2 validated wolfCrypt library for all cryptographic functionality. Visit http://wolfssl.com/wolfSSL/fips.html for more info!

yaSSL, or yet another SSL, is an embedded ssl library for programmers building security functionality into their applications and devices. yaSSL is highly portable, and runs on standard as well as embedded platforms(QNX, ThreadX, VxWorks, Tron) yaSSL is still available but no longer being developed. Current development on the same project continues under wolfSSL. Visit yaSSL Home above for the latest stable release.

OmniEdge is an Open source p2p layer 2 , zero-config mesh VPN infrastructure, a traditional VPN, AWS VPC, Ngrok, DDNS alternative. No central server, easy to scale with less maintenance. What happens in intranet, stays in in intranet.