48 lines
		
	
	
		
			1.1 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
			
		
		
	
	
			48 lines
		
	
	
		
			1.1 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
| "use strict";
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| 
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| const {isIP} = require("net");
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| const execa = require("execa");
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| const dests = new Set(["default", "0.0.0.0", "0.0.0.0/0", "::", "::/0"]);
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| 
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| const args = {
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|   v4: ["-rn", "-f", "inet"],
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|   v6: ["-rn", "-f", "inet6"],
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| };
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| 
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| const parse = stdout => {
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|   let result;
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| 
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|   (stdout || "").trim().split("\n").some(line => {
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|     const results = line.split(/ +/) || [];
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|     const target = results[0];
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|     const gateway = results[1];
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|     const iface = results[7];
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|     if (dests.has(target) && gateway && isIP(gateway)) {
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|       result = {gateway, interface: (iface ? iface : null)};
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|       return true;
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|     }
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|   });
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| 
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|   if (!result) {
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|     throw new Error("Unable to determine default gateway");
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|   }
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| 
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|   return result;
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| };
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| 
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| const promise = async family => {
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|   const {stdout} = await execa("netstat", args[family]);
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|   return parse(stdout);
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| };
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| 
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| const sync = family => {
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|   const {stdout} = execa.sync("netstat", args[family]);
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|   return parse(stdout);
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| };
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| 
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| module.exports.v4 = () => promise("v4");
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| module.exports.v6 = () => promise("v6");
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| 
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| module.exports.v4.sync = () => sync("v4");
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| module.exports.v6.sync = () => sync("v6");
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