locutus/golang/net/ParseCIDR.js

Locutus other languages' standard libraries to JavaScript for fun and educational purposes

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.ParseCIDR = ParseCIDR;
const ParseIP_ts_1 = require("./ParseIP.js");
function ParseCIDR(value) {
    //      discuss at: https://locutus.io/golang/net/ParseCIDR/
    // parity verified: Go 1.23
    //     original by: Kevin van Zonneveld (https://kvz.io)
    //          note 1: Parses CIDR notation and returns normalized IP plus prefix length.
    //          note 2: Returns null when either the IP or mask width is invalid.
    //       example 1: ParseCIDR('192.168.0.1/24')
    //       returns 1: {ip: '192.168.0.1', maskBits: 24}
    //       example 2: ParseCIDR('2001:db8::1/64')
    //       returns 2: {ip: '2001:db8::1', maskBits: 64}
    //       example 3: ParseCIDR('192.168.0.1/99')
    //       returns 3: null
    const input = String(value);
    const slashIndex = input.indexOf('/');
    if (slashIndex <= 0 || slashIndex !== input.lastIndexOf('/')) {
        return null;
    }
    const ipPart = input.slice(0, slashIndex);
    const maskPart = input.slice(slashIndex + 1);
    if (!/^\d+$/.test(maskPart)) {
        return null;
    }
    const normalizedIp = (0, ParseIP_ts_1.ParseIP)(ipPart);
    if (normalizedIp === null) {
        return null;
    }
    const maxBits = normalizedIp.includes(':') ? 128 : 32;
    const maskBits = Number(maskPart);
    if (!Number.isInteger(maskBits) || maskBits < 0 || maskBits > maxBits) {
        return null;
    }
    return {
        ip: normalizedIp,
        maskBits,
    };
}