Install sslsplit with Homebrew

Project links

• Homepage
• Repository

Commands and aliases

• sslsplit

Project history

The official project page says SSLsplit is developed by Daniel Roethlisberger and contributors and was first publicly released as 0.4.2 in 2012. Its README says it was inspired by Claes M. Nyberg's mitm-ssl and Moxie Marlinspike's sslsniff, while sharing no source code with them.

SSLsplit is designed to transparently terminate NAT-redirected connections, create a new SSL/TLS connection to the original destination, and log transmitted data. Over time it added defenses against mechanisms that complicate interception, including OCSP handling, HSTS and HPKP header mangling, Expect-CT suppression, and prevention of protocol upgrades such as QUIC, SPDY, HTTP/2, and WebSockets.

Adoption history

The official project page lists package or port availability across FreeBSD, OpenBSD, NetBSD, DragonFly BSD, Homebrew, Arch Linux, Debian, Ubuntu, Gentoo, Fedora/RHEL/CentOS, openSUSE, Mageia, BlackArch, Kali Linux, and related security distributions or appliances. The supplied package metadata also shows Homebrew, Debian, Fedora, Nix, Arch, and Ubuntu packaging.

Its packaging footprint follows from its role in labs and security distributions: users need a reproducible build of a sensitive interception tool with OpenSSL, libevent, libpcap, libnet, NAT engine support, and platform-specific behavior aligned.

How it is used

Typical usage requires redirecting traffic with a platform NAT engine, then running sslsplit with proxy specifications such as http, https, tcp, ssl, or autossl, CA certificate/key material, and logging destinations. The tool can write connection logs, content logs, PCAP output, mirrored packets, generated certificates, master secrets, and local process information.

Supported NAT mechanisms in official documentation include FreeBSD pf rdr and divert-to, ipfw fwd, ipfilter rdr; OpenBSD pf rdr-to and divert-to; Linux netfilter REDIRECT and TPROXY; and macOS pf rdr and ipfw fwd.

Why package nerds care

SSLsplit is package-nerd significant because it is deeply coupled to OS networking facilities. A useful package is not only the binary; it is the right combination of OpenSSL compatibility, NAT-engine support, privilege behavior, man pages, sample configuration, and logging defaults.

It also belongs to the family of security tools whose value is inseparable from ethical context. Distributions package it for legitimate forensics, testing, and education, but its capability is explicitly man-in-the-middle interception.

Timeline

• 2012: SSLsplit 0.4.2 was the first public release.
• 2013: Version 0.4.7 filtered HPKP headers and added HTTP status and content length to connection logs.
• 2014: Versions 0.4.8 through 0.4.10 improved pf support on macOS, added protocol forcing options, and added separate file logging with process information.
• 2016: Version 0.5.0 added generic STARTTLS support through the autossl proxy specification and introduced privilege separation.
• 2018: Version 0.5.4 added PCAP and packet-mirroring content log modes and the sslsplit.conf manual page.
• 2019: Version 0.5.5 fixed packaging and install-path behavior, including SYSCONFDIR-controlled installation of sample config files.

Related projects

• Official README names mitm-ssl and sslsniff as inspirations.
• Related operational tools include OpenSSL, libevent, libpcap, libnet, platform NAT engines, Wireshark via PCAP or SSLKEYLOGFILE-style outputs, and security distributions such as Kali and BlackArch.

Sources

• https://github.com/droe/sslsplit#readme
• https://github.com/droe/sslsplit/blob/master/NEWS.md
• https://www.roe.ch/SSLsplit
• input source_facts.package-manager