Class ManagedProxyConnector

Namespace

VpnHood.Core.Proxies.Management

Assembly

VpnHood.Core.Proxies.Management.dll

Provides the VPN's connections through a managed list of proxies, kept in an IProxyEndPointStore: it rates the endpoints by their successes and failures, rotates them, checks them, and may update the list from a URL.

public class ManagedProxyConnector : IProxyConnector, IAsyncDisposable

Inheritance

object

ManagedProxyConnector

Implements

IProxyConnector

IAsyncDisposable

Inherited Members

object.Equals(object)

object.Equals(object, object)

object.GetHashCode()

object.GetType()

object.MemberwiseClone()

object.ReferenceEquals(object, object)

object.ToString()

Remarks

A connection tries the enabled endpoints in turn, the one whose turn comes soonest first: an endpoint's next turn moves back by 3 for each point of its penalty. While any endpoint succeeded last, only the first of those that did not keeps its place, and the rest go to the end. When the first endpoint in that order did not succeed last, the endpoints are checked first: the unrated ones all, the others until one succeeds.

A check connects through each enabled endpoint, up to 50 at a time, to 1.1.1.1:443, with VerifyTls also through a TLS handshake with one.one.one.one, and records each outcome; once 10 have succeeded, it checks only those never rated. An endpoint whose check fails with a ProxyClientException of ProtocolNotSupported or AccessDenied, as an AuthenticationException in the check's TLS handshake becomes, is disabled. The statuses are saved to the store every 10 seconds, after a check, and at the disposal.

Properties

IsEnabled

Gets a value indicating whether the connector has a proxy to connect through.

public bool IsEnabled { get; }

Property Value

bool

true while the store has any endpoint, as last loaded.

Progress

Gets the progress of a check of the endpoints under way, or null.

public ProgressStatus? Progress { get; }

Property Value

ProgressStatus?

Status

Gets the connector's state, made at each read.

public ProxyConnectorStatus Status { get; }

Property Value

ProxyConnectorStatus

UseRecentSucceeded

Gets or sets a value indicating whether connections use only the endpoints that have succeeded since the connector was made, where there is a list to choose from.

public bool UseRecentSucceeded { get; set; }

Property Value

bool

Methods

CheckServers(ISocketFactory, CancellationToken)

Checks the endpoints, where the connector has a list to check, and records what it finds.

public Task CheckServers(ISocketFactory socketFactory, CancellationToken cancellationToken)

Parameters

socketFactory ISocketFactory

The factory of the sockets to the proxies, which keeps them out of the tunnel.

cancellationToken CancellationToken

The token to monitor for cancellation requests.

Returns

Task

A task that represents the asynchronous operation.

Remarks

It checks the enabled endpoints, the best first, and skips the rest of those already rated once 10 have succeeded; see the class's remarks. What it recorded is saved even when it is canceled. The update from a URL checks with the last factory a caller gave.

Exceptions

OperationCanceledException

cancellationToken was canceled.

ConnectAsync(ISocketFactory, IPEndPoint, Action?, CancellationToken)

Connects to an endpoint through a proxy.

public Task<TcpClient> ConnectAsync(ISocketFactory socketFactory, IPEndPoint ipEndPoint, Action? onAttempt, CancellationToken cancellationToken)

Parameters

socketFactory ISocketFactory

The factory of the sockets to the proxies: the caller's, which keeps them out of the tunnel.

ipEndPoint IPEndPoint

The endpoint to reach through the proxy.

onAttempt Action

Called after each proxy the connector tried, or null.

cancellationToken CancellationToken

The token to monitor for cancellation requests.

Returns

Task<TcpClient>

A task whose result is the connection, through the proxy, which the caller owns. Its stream is the raw TCP one, not an HTTPS proxy's TLS tunnel.

Remarks

One connection at a time chooses its order, and waits for the check that runs when the first endpoint did not succeed last. Each success and failure is recorded, and reported to onAttempt; a failure taken for the caller's cancellation, any OperationCanceledException within the check timeout, is neither, and a cancellation during the last attempt ends in the SocketException. With RemoveDuplicateIps, a success disables the other endpoints of its host and protocol among those the connection could choose. The connector keeps the last socket factory for its checks.

Exceptions

SocketException

No endpoint could connect, with NetworkUnreachable.

ObjectDisposedException

The connector was disposed.

OperationCanceledException

cancellationToken was canceled.

Create(ProxyOptions, IProxyEndPointStore, TimeSpan?, CancellationToken)

Creates a connector with its endpoints already loaded from the store, so IsEnabled and Status hold from the start, and starts its update from a URL where the options ask for one.

public static Task<ManagedProxyConnector> Create(ProxyOptions proxyOptions, IProxyEndPointStore store, TimeSpan? serverCheckTimeout, CancellationToken cancellationToken)

Parameters

proxyOptions ProxyOptions

The options; with ResetStates, the stored statuses are cleared first, which logs a failure rather than throwing it.

store IProxyEndPointStore

The store of the endpoints, which the connector disposes with itself.

serverCheckTimeout TimeSpan?

How long a check of an endpoint may take, or null for 7 seconds.

cancellationToken CancellationToken

The token to monitor for cancellation requests.

Returns

Task<ManagedProxyConnector>

A task whose result is the connector.

Exceptions

OperationCanceledException

cancellationToken was canceled.

DisposeAsync()

Stops the update and the saving, saves the statuses not saved yet, logging a failure, and disposes the store.

public ValueTask DisposeAsync()

Returns

ValueTask

A task that represents the asynchronous operation.

Flush(CancellationToken)

Saves the endpoints' statuses not saved yet, where the connector keeps any.

public Task Flush(CancellationToken cancellationToken)

Parameters

cancellationToken CancellationToken

The token to monitor for cancellation requests.

Returns

Task

A task that represents the asynchronous operation.

Remarks

It saves the changed statuses and enabled states, and the queue position.

Exceptions

OperationCanceledException

cancellationToken was canceled.

GetEndPointInfos()

Gets the endpoints the connector holds, with their statuses.

public IReadOnlyList<ProxyEndPointInfo> GetEndPointInfos()

Returns

IReadOnlyList<ProxyEndPointInfo>

The connector's own endpoint and status objects, which later connections update.

RecordFailed(TcpClient, Exception)

Records a failure of a connection ConnectAsync(ISocketFactory, IPEndPoint, Action?, CancellationToken) made, after it was made, as in a TLS handshake over it, against the proxy that made it.

public void RecordFailed(TcpClient tcpClient, Exception ex)

Parameters

tcpClient TcpClient

The connection.

ex Exception

The failure.

Remarks

It counts once per connection: the endpoint's success is taken back and a failure recorded. A connection it did not hand out changes nothing; for an OperationCanceledException within the check timeout after the connection was made, the connection is forgotten with no failure recorded.

UpdateOptions(ProxyOptions, CancellationToken)

Takes new options.

public Task UpdateOptions(ProxyOptions proxyOptions, CancellationToken cancellationToken)

Parameters

proxyOptions ProxyOptions

The options.

cancellationToken CancellationToken

The token to monitor for cancellation requests.

Returns

Task

A task that represents the asynchronous operation.

Remarks

It saves the statuses not saved yet, or, with ResetStates, clears the stored ones instead, then loads the endpoints from the store again. The update from a URL starts again, with a download at once, only when its URL or interval changed.

Exceptions

OperationCanceledException

cancellationToken was canceled.