Add auth to local proxy

[DimaT1980]

Issue Details

Sometimes some applications (such as banking applications or others from large providers) scan local ports for open HTTP/SOCKS proxies. When such a proxy is detected, they make an unauthorized connection to it and make a request to their server through that proxy. This reveals the proxy's IP address, allowing it to be blacklisted globally on country provider level. This is currently a serious problem—the local SOCKS server is unprotected, and sometimes we need that local proxy running
Article - https://habr.com/ru/articles/1020080/
POC application - https://github.com/runetfreedom/per-app-split-bypass-poc

Proposed solution

SOCKS server authentication has been added using login and password, which can be configured in a separate settings section.

Alternative solution

No response

[08mvi54-pixel]

There is growing attention to the practice whereby mobile applications scan a device’s local ports and adjust their behavior depending on the results of such scanning (e.g. VPN detactors). This allows applications to indirectly detect the usage of a VPN-tunnel or other proxy- or traffic-routing mechanisms by identifying the availability of a local open proxy port.

At the same time, when VPN mode is enabled, it is not always necessary to continuously make some proxy port available and forward traffic through it (e.g. 127.0.0.1:1080 or any similar port).

It would be advisable to provide a dedicated toggle in the AdGuard VPN application to enable or disable traffic forwarding through the relevant local port. Such a feature would allow users, where necessary, to disable this mechanism and thereby reduce the ability of applications to detect it when attempting to determine the device’s network configuration.

[ESurina]

We will add it in the next version!

[okSashaok]

Система авторизации на прокси будет очень уместной, так как эта реальная проблема. Будет интересно увидеть, как разрешится данный вопрос, так как эта не единственная проблема в борьбе со всякими нелегалами.