How to check if a given ip falls between a given ip range using node js

Question

Please pardon for this trival question

Given a set of Ip the set is quite large and might increase https://github.com/client9/ipcat/blob/master/datacenters.csv#L4

Small example set - first column start ip second - end ip range

I will get the user ip from the request . I need to check if the ip falls in these set of ranges . How do i accomplish this.

I have looked into ip_range_check and range_check.

But they donot check for a ip given given range . How is thhis possible in node js with utmost performance. I dont want to go for a exhaustive search as performance is a hight priority.

Please help something new and quite challenging so far to me.

Solution 1

This is quite easy if we convert the ips to simple numbers:

function IPtoNum(ip){
  return Number(
    ip.split(".")
      .map(d => ("000"+d).substr(-3) )
      .join("")
  );
}

Then we can check a certain range as:

 if( IPtoNum(min) < IPtoNum(val) &&    IPtoNum(max) > IPtoNum(val) ) alert("in range");

That can also be applied to a table:

const ranges = [
  ["..41", "192.168.45"],
  ["123.124.125"," 126.124.123"]
];

const ip = "125.12.125";
const inRange = ranges.some(
  ([min,max]) => IPtoNum(min) < IPtoNum(ip) &&   IPtoNum(max) > IPtoNum(ip)
);

Solution 2

//Use getCIDR from rangecalc
getCIDR("5.9.0.0", "5.9.255.255")
//This return 5.9.0.0/16

//You can then use ipRangeCheck from ip_range_check
ipRangeCheck("IP TO BE CHECKED", "5.9.0.0/16")
//returns true or false

Pretty sure there's other way to do this.

Comments

[INFOSYS]

This would work but this will be exhaustive right like brute force. Something more performance wise will be better as we have huge ip range dnt you think. Still a solution none the less

[Deja]

This might be helpful iptrie

[INFOSYS]

Thanks for this answer but taking into account the large ip set will it be fast or give a good performance of the ip we need to check resides at the bottom of the table

[Jonas Wilms]

@infosys one could optimize it through converting the table from ips to numbers once. ( and i think further optimizations require big memory consumtion ) And have a look at bloom filters, they might do what youre looking for.

[INFOSYS]

Thanks i will convert ip to numbers not an issue that function wont be required but what is bloom filter how to add it to that and search ?. I will up vote the answet and accept it too

[Jonas Wilms]

@infosys youre welcome ;) , as i said, if you use big tables for lookup (e.g. every ip address is stored as a boolean), then you have huge memory consumtion, but its very fast. Bloom filters do that with smaller memory but with loosing precision.

[INFOSYS]

I looked into bloom filters it like a hashtable of java. But how to insert the ip range and get the ip range this might be another question that hits my mind . Or how to search the bloom folter with min max?

[Jonas Wilms]

@infosys you cant search . the table would be huge. Thats a simple memory vs. performance discussion. And yeah, that would be a few other questions...

[INFOSYS]

may be you can check this stackoverflow.com/questions/46203516/…