Fix server 'hostname' option to mitigate DNS rebinding attack #1678
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feross
commented
Jul 30, 2019
lib/server.js
Outdated
| @@ -218,6 218,11 @@ function Server (torrent, opts = {}) { | |||
| const html = getPageHTML('405 - Method Not Allowed', '<h1>405 - Method Not Allowed</h1>') | |||
| res.end(html) | |||
| } | |||
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| function serveEmptyResponse () { | |||
| res.statusCode = 204 | |||
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Ideally, we'd just kill the whole TCP connection without responding at all but I'm not sure if there's a clean way to do this from the http layer. Looking into it.
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lgtm |
It appears that this feature, originally added in #1260, never worked correctly. When the request hostname does not match the user-provided opts.hostname value, we should stop processing the request and return nothing. Instead, what was happening was that we'd simply omit the Access-Control-Allow-Origin header, which is not sufficient since the whole point of DNS rebinding attacks is that they appear same origin and therefore don't require a CORS header.
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Nice, figured out how to kill the connection without sending a response. Merging now. |
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0.105.2 |
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It appears that this feature, originally added in #1260, may have never worked correctly.
When the request hostname does not match the user-provided opts.hostname value, we should stop processing the request and return nothing. Instead, what was happening was that we'd simply omit the Access-Control-Allow-Origin header, which is not sufficient since the whole point of DNS rebinding attacks is that they appear to be same origin and therefore don't require a CORS header.
cc @diracdeltas @yrliou