Hello Community,
I was able to build this out.
This solution is dependent on how you want to capture the SSL Cert information for your server.
- You can either run a command internally on the server to see the certs installed and capture that information, or
- You can run an external command that will capture the SSL cert information via externally connecting to the ssl port to request the header/thumbprint/output of the ssl cert. (This method will prove tricky because you would have to manually change the script on the probe to execute on every server, unless there is a script that can loop through all the known IPs/URLs to extract the Certs and associate them to the targeted CI)
For now I will use use case # 1 as an example:
- to check for certs installed locally/internally on the server we would have to know where the certs install files are located, we can do this by creating a probe to capture all locations of where .crt files are located (if needed, we can create a sensor to parse through the output to capture all the installed locations of the .crt file to populate the CI but I did not complete this step but when you read through this write up, you can tweak the script i have to collect cert expiration date to meet this need):
locate *.crt
- Once you get the output locations of where local certs are installed on the server, run this command while swapping out the files location with your own:
openssl x509 -text -noout -in /etc/pki/tls/certs/localhost.crt
You can use these commands that are referenced/explained in the following URLs
Windows based servers:
How can I get a list of installed certificates on Windows? - Super User
Linux based servers:
The Most Common OpenSSL Commands - After I created my probe, I then created the corresponding sensor to parse the output and relate them to the CI.
- I then created this java script for the sensor to parse through the output and grab the "End date" of the ssl cmd.
/*
new DiscoverySensor({
process: function(result) {
var ssloutput = result."Not After : ";
var ssldate = new setDisplayValue();
ssldate.addSeconds(-ssloutput);
current.u_ssl_exp = ssldate;
},
type: "DiscoverySensor"
});
*/
new DiscoverySensor({
process: function(result) {
if (gs.nil(result.output))
return;
this.parseOutput(result.output);
},
parseOutput: function(output) {
var updated = false;
var lines = output.split(/\n/);
gs.log("This is the output for lines: "+lines);
gs.log("Not After Index check >>>> "+output.indexOf("Not After"));
var na = output.indexOf("Not After");
gs.log(output.substring(na + 12, na + 32)); //to grab full date output
gs.log(output.substring(na + 28, na + 32)); //to grab year
gs.log(output.substring(na + 12, na + 15)); //to grab month
gs.log(output.substring(na + 16, na + 18)); //to grab day
gs.log(output.substring(na + 19, na + 27)); //to grab time
var yyyy = output.substring(na + 28, na + 32);
var mmm = output.substring(na + 12, na + 15);
var dd = output.substring(na + 16, na + 18);
var time = output.substring(na + 19, na + 27);
//convert cert output date to match servicenow date format.
var mn;
if (mmm == "Jan"){
mn = "01";
} else if(mmm == "Feb"){
mn = "02";
}else if(mmm == "Mar"){
mn = "03";
}else if(mmm == "Apr"){
mn = "04";
}else if(mmm == "May"){
mn = "05";
}else if(mmm == "Jun"){
mn = "06";
}else if(mmm == "Jul"){
mn = "07";
}else if(mmm == "Aug"){
mn = "08";
}else if(mmm == "Sep"){
mn = "09";
}else if(mmm == "Oct"){
mn = "10";
}else if(mmm == "Nov"){
mn = "11";
}else if(mmm == "Dec"){
mn = "12";
}
gs.log("This is the output for mn: "+mn);
//gs.log(yyyy+"-"+mn+"-"+dd+" "+time);
var sslexpdate = yyyy+"-"+mn+"-"+dd+" "+time;
gs.log(sslexpdate);
updated = true;
if (updated) //Only update it if the output has good value
current.u_ssl_exp = sslexpdate;
//gs.log("The month number is "+mn);
//for (var i = 0; i < lines.length; i++) {
//var line = lines[i];
//gs.log("This is the output for line: "+line);
//var parts = line.split(":");
//var name = parts[0].trim();
//var value = parts[1].trim();
//gs.log("Not After Index check >>>> "+output.indexOf("Not After"));
//if (name == "Not After")
//current.u_ssl_exp = value;
//gs.log("The name is "+name+" and value is "+ value);
//gs.log("Not After Index check >>>> "+output.indexOf("Not After"));
//gs.log("The name is "+name+" and length is "+ name.length);
//}
},
type: "DiscoverySensor"
});
5. Take notice that I also had to convert the output of the SSL cert date to match servicenow's date format i.e. variables "mmm", "mn" (for month number), and rearranging the date.
6. Attach the sensor to the probe.
7. Test the probe to see if there are any errors to re-mediate.
i.e. of error
i.e. of working probe:
8. For trouble shooting of the script you can make your way to Script Log Statements to see how your sensor code is parsing through the output.
9. I then created the corresponding variable on the CI called "u_ssl_exp" that is referenced on line 75 of my sensor code.
9. create a discovery schedule.
10. Scan will run, check with Discovery status, event logs, all (logs), script log statements, etc. to see status
11. Verify the CI field has been updated with the SSL expiration date:
12. Now that we have a servicenow format for a tangible date for the ssl cert, we can now have servicenow automate notifications based on cert expiration etc.
Note: The commented out portions of my code also has portions that increment, or loop, through the ssl cert output to grab any other information if needed (it is separated by ":"). Please feel free to update the code and post here to share with the rest of the community any updated codes, practices, or methods, etc.
I hope this helps you all as much as it has helped me.
Thank you.
