net: support blocklist for net.Server · nodejs/node@b47888d

**Default:** `false`.

* `pauseOnConnect` {boolean} Indicates whether the socket should be

paused on incoming connections. **Default:** `false`.

* `blockList` {net.BlockList} `blockList` can be used for disabling inbound

access to specific IP addresses, IP ranges, or IP subnets. This does not

work if the server is behind a reverse proxy, NAT, etc. because the address

checked against the block list is the address of the proxy, or the one

specified by the NAT.

* `connectionListener` {Function} Automatically set as a listener for the

[`'connection'`][] event.

this.keepAlive = Boolean(options.keepAlive);

this.keepAliveInitialDelay = ~~(options.keepAliveInitialDelay / 1000);

this.highWaterMark = options.highWaterMark ?? getDefaultHighWaterMark();

if (options.blockList) {

// TODO: use BlockList.isBlockList (https://github.com/nodejs/node/pull/56078)

if (!(options.blockList instanceof module.exports.BlockList)) {

throw new ERR_INVALID_ARG_TYPE('options.blockList', 'net.BlockList', options.blockList);

}

this.blockList = options.blockList;

}

}

ObjectSetPrototypeOf(Server.prototype, EventEmitter.prototype);

ObjectSetPrototypeOf(Server, EventEmitter);

clientHandle.close();

return;

}

if (self.blockList && typeof clientHandle.getpeername === 'function') {

const remoteInfo = { __proto__: null };

clientHandle.getpeername(remoteInfo);

const addressType = isIP(remoteInfo.address);

if (addressType && self.blockList.check(remoteInfo.address, `ipv${addressType}`)) {

clientHandle.close();

return;

}

}

const socket = new Socket({

handle: clientHandle,

allowHalfOpen: self.allowHalfOpen,

'use strict';

const common = require('../common');

const net = require('net');

const blockList = new net.BlockList();

blockList.addAddress(common.localhostIPv4);

const server = net.createServer({ blockList }, common.mustNotCall());

server.listen(0, common.localhostIPv4, common.mustCall(() => {

const adddress = server.address();

const socket = net.connect({

localAddress: common.localhostIPv4,

host: adddress.address,

port: adddress.port

});

socket.on('close', common.mustCall(() => {

server.close();

}));

}));