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KaKi87/isIpInCidr.js

Created February 20, 2020 17:36
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Is IP in CIDR ?
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isIpInCidr.js
const isIpInCidr = (ip, cidr) => {
const [range, bits = 32] = cidr.split('/');
const mask = ~(2 ** (32 - bits) - 1);
const ip4ToInt = ip => ip.split('.').reduce((int, oct) => (int << 8) + parseInt(oct, 10), 0) >>> 0;
return (ip4ToInt(ip) & mask) === (ip4ToInt(range) & mask);
};
/*
Source : https://tech.mybuilder.com/determining-if-an-ipv4-address-is-within-a-cidr-range-in-javascript/
*/
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