self-signed-cert.lua

--[[
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Stamus Networks

Self-signed certificate rule example below
alert tls any any -> any any (msg:"SURICATA TLS Self Signed Certificate"; flow:established; luajit:self-signed-cert.lua;  classtype:protocol-command-decode; sid:999666111; rev:1;)

This script is possible thanks to - 
https://github.com/inliniac/suricata/pull/1585
]]

function init (args)
    local needs = {}
    needs["tls"] = tostring(true)
    return needs
end

function match(args)
    version, subject, issuer, fingerprint = TlsGetCertInfo();
    
    if subject == issuer then
        --[[selfSigned = string.format("\nIssuer: %s\nSubject: %s\n are the same.\nSelf Signed Certificate!\n",
                        issuer, subject)
        print(string.format("\nIssuer: %s\nSubject: %s\nare the same.\nSelf Signed Certificate!\n",
                        issuer, subject))]]
        return 1
    else
        return 0
    end
    --[[str = string.format("\nVersion %s\nIssuer %s\nSubject %s\nFingerprint %s",
                        version, issuer, subject, fingerprint)
    SCLogInfo(str);]]
end