/// <summary>
/// Establishes a connection to the specified SMTP server.
/// </summary>
/// <remarks>
/// <para>Establishes a connection to an SMTP or SMTP/S server. If the schema
/// in the uri is "smtp", a clear-text connection is made and defaults to using
/// port 25 if no port is specified in the URI. However, if the schema in the
/// uri is "smtps", an SSL connection is made using the
/// <see cref="ClientCertificates"/> and defaults to port 465 unless a port
/// is specified in the URI.</para>
/// <para>It should be noted that when using a clear-text SMTP connection,
/// if the server advertizes support for the STARTTLS extension, the client
/// will automatically switch into TLS mode before authenticating unless the
/// <paramref name="uri"/> contains a query string to disable it.</para>
/// If a successful connection is made, the <see cref="AuthenticationMechanisms"/>
/// and <see cref="Capabilities"/> properties will be populated.
/// </remarks>
/// <param name="uri">The server URI. The <see cref="System.Uri.Scheme"/> should either
/// be "smtp" to make a clear-text connection or "smtps" to make an SSL connection.</param>
/// <param name="cancellationToken">A cancellation token.</param>
/// <exception cref="System.ArgumentNullException">
/// <para>The <paramref name="uri"/> is <c>null</c>.</para>
/// </exception>
/// <exception cref="System.ArgumentException">
/// The <paramref name="uri"/> is not an absolute URI.
/// </exception>
/// <exception cref="System.ObjectDisposedException">
/// The <see cref="SmtpClient"/> has been disposed.
/// </exception>
/// <exception cref="System.InvalidOperationException">
/// The <see cref="SmtpClient"/> is already connected.
/// </exception>
/// <exception cref="System.OperationCanceledException">
/// The operation was canceled.
/// </exception>
/// <exception cref="System.IO.IOException">
/// An I/O error occurred.
/// </exception>
/// <exception cref="SmtpCommandException">
/// An SMTP command failed.
/// </exception>
/// <exception cref="SmtpProtocolException">
/// An SMTP protocol error occurred.
/// </exception>
public void Connect(Uri uri, CancellationToken cancellationToken = default (CancellationToken))
{
CheckDisposed ();
if (uri == null)
throw new ArgumentNullException ("uri");
if (!uri.IsAbsoluteUri)
throw new ArgumentException ("The uri must be absolute.", "uri");
if (IsConnected)
throw new InvalidOperationException ("The SmtpClient is already connected.");
capabilities = SmtpCapabilities.None;
authmechs.Clear ();
MaxSize = 0;
var smtps = uri.Scheme.ToLowerInvariant () == "smtps";
var port = uri.Port > 0 ? uri.Port : (smtps ? 465 : 25);
var query = uri.ParsedQuery ();
SmtpResponse response = null;
string value;
var starttls = !smtps && (!query.TryGetValue ("starttls", out value) || Convert.ToBoolean (value));
#if !NETFX_CORE
var ipAddresses = Dns.GetHostAddresses (uri.DnsSafeHost);
Socket socket = null;
for (int i = 0; i < ipAddresses.Length; i++) {
socket = new Socket (ipAddresses[i].AddressFamily, SocketType.Stream, ProtocolType.Tcp);
cancellationToken.ThrowIfCancellationRequested ();
try {
socket.Connect (ipAddresses[i], port);
localEndPoint = socket.LocalEndPoint;
break;
} catch {
if (i + 1 == ipAddresses.Length)
throw;
}
}
if (smtps) {
var ssl = new SslStream (new NetworkStream (socket, true), false, ValidateRemoteCertificate);
ssl.AuthenticateAsClient (uri.Host, ClientCertificates, SslProtocols.Default, true);
stream = ssl;
} else {
stream = new NetworkStream (socket, true);
}
#else
socket = new StreamSocket ();
cancellationToken.ThrowIfCancellationRequested ();
socket.ConnectAsync (new HostName (uri.DnsSafeHost), port.ToString (), smtps ? SocketProtectionLevel.Tls12 : SocketProtectionLevel.PlainSocket)
.AsTask (cancellationToken)
.GetAwaiter ()
.GetResult ();
stream = new DuplexStream (socket.InputStream.AsStreamForRead (), socket.OutputStream.AsStreamForWrite ());
#endif
if (stream.CanTimeout) {
stream.WriteTimeout = timeout;
stream.ReadTimeout = timeout;
}
host = uri.Host;
logger.LogConnect (uri);
try {
// read the greeting
response = ReadResponse (cancellationToken);
if (response.StatusCode != SmtpStatusCode.ServiceReady)
throw new SmtpCommandException (SmtpErrorCode.UnexpectedStatusCode, response.StatusCode, response.Response);
// Send EHLO and get a list of supported extensions
Ehlo (cancellationToken);
if (starttls && (capabilities & SmtpCapabilities.StartTLS) != 0) {
response = SendCommand ("STARTTLS", cancellationToken);
if (response.StatusCode != SmtpStatusCode.ServiceReady)
throw new SmtpCommandException (SmtpErrorCode.UnexpectedStatusCode, response.StatusCode, response.Response);
#if !NETFX_CORE
var tls = new SslStream (stream, false, ValidateRemoteCertificate);
tls.AuthenticateAsClient (uri.Host, ClientCertificates, SslProtocols.Tls, true);
stream = tls;
#else
socket.UpgradeToSslAsync (SocketProtectionLevel.Tls12, new HostName (uri.DnsSafeHost))
.AsTask (cancellationToken)
.GetAwaiter ()
.GetResult ();
#endif
// Send EHLO again and get the new list of supported extensions
Ehlo (cancellationToken);
}
IsConnected = true;
} catch {
stream.Dispose ();
stream = null;
throw;
}
}
/// <summary>
/// Establishes a connection to the specified POP3 server.
/// </summary>
/// <remarks>
/// <para>Establishes a connection to an POP3 or POP3/S server. If the schema
/// in the uri is "pop", a clear-text connection is made and defaults to using
/// port 110 if no port is specified in the URI. However, if the schema in the
/// uri is "pops", an SSL connection is made using the
/// <see cref="ClientCertificates"/> and defaults to port 995 unless a port
/// is specified in the URI.</para>
/// <para>It should be noted that when using a clear-text POP3 connection,
/// if the server advertizes support for the STLS extension, the client
/// will automatically switch into TLS mode before authenticating unless
/// the <paramref name="uri"/> contains a query string to disable it.</para>
/// If a successful connection is made, the <see cref="AuthenticationMechanisms"/>
/// and <see cref="Capabilities"/> properties will be populated.
/// </remarks>
/// <param name="uri">The server URI. The <see cref="System.Uri.Scheme"/> should either
/// be "pop" to make a clear-text connection or "pops" to make an SSL connection.</param>
/// <param name="cancellationToken">A cancellation token.</param>
/// <exception cref="System.ArgumentNullException">
/// The <paramref name="uri"/> is <c>null</c>.
/// </exception>
/// <exception cref="System.ArgumentException">
/// The <paramref name="uri"/> is not an absolute URI.
/// </exception>
/// <exception cref="System.ObjectDisposedException">
/// The <see cref="Pop3Client"/> has been disposed.
/// </exception>
/// <exception cref="System.InvalidOperationException">
/// The <see cref="Pop3Client"/> is already connected.
/// </exception>
/// <exception cref="System.OperationCanceledException">
/// The operation was canceled via the cancellation token.
/// </exception>
/// <exception cref="System.IO.IOException">
/// An I/O error occurred.
/// </exception>
/// <exception cref="Pop3CommandException">
/// A POP3 command failed.
/// </exception>
/// <exception cref="Pop3ProtocolException">
/// A POP3 protocol error occurred.
/// </exception>
public void Connect(Uri uri, CancellationToken cancellationToken)
{
CheckDisposed ();
if (uri == null)
throw new ArgumentNullException ("uri");
if (!uri.IsAbsoluteUri)
throw new ArgumentException ("The uri must be absolute.", "uri");
if (IsConnected)
throw new InvalidOperationException ("The Pop3Client is already connected.");
var scheme = uri.Scheme.ToLowerInvariant ();
var pops = scheme == "pops" || scheme == "pop3s";
var port = uri.Port > 0 ? uri.Port : (pops ? 995 : 110);
var query = uri.ParsedQuery ();
#if !NETFX_CORE && !WINDOWS_APP && !WINDOWS_PHONE_APP
var ipAddresses = Dns.GetHostAddresses (uri.DnsSafeHost);
Socket socket = null;
#endif
Stream stream;
string value;
var starttls = !pops && (!query.TryGetValue ("starttls", out value) || Convert.ToBoolean (value));
#if !NETFX_CORE && !WINDOWS_APP && !WINDOWS_PHONE_APP
for (int i = 0; i < ipAddresses.Length; i++) {
socket = new Socket (ipAddresses[i].AddressFamily, SocketType.Stream, ProtocolType.Tcp);
cancellationToken.ThrowIfCancellationRequested ();
try {
socket.Connect (ipAddresses[i], port);
break;
} catch (Exception) {
if (i + 1 == ipAddresses.Length)
throw;
}
}
if (pops) {
var ssl = new SslStream (new NetworkStream (socket, true), false, ValidateRemoteCertificate);
ssl.AuthenticateAsClient (uri.Host, ClientCertificates, SslProtocols.Default, true);
stream = ssl;
} else {
stream = new NetworkStream (socket, true);
}
#else
socket = new StreamSocket ();
cancellationToken.ThrowIfCancellationRequested ();
socket.ConnectAsync (new HostName (uri.DnsSafeHost), port.ToString (), pops ? SocketProtectionLevel.Tls12 : SocketProtectionLevel.PlainSocket)
.AsTask (cancellationToken)
.GetAwaiter ()
.GetResult ();
stream = new DuplexStream (socket.InputStream.AsStreamForRead (), socket.OutputStream.AsStreamForWrite ());
#endif
probed = ProbedCapabilities.None;
host = uri.Host;
logger.LogConnect (uri);
engine.Connect (new Pop3Stream (stream, logger), cancellationToken);
engine.QueryCapabilities (cancellationToken);
if (starttls && (engine.Capabilities & Pop3Capabilities.StartTLS) != 0) {
SendCommand (cancellationToken, "STLS");
#if !NETFX_CORE && !WINDOWS_APP && !WINDOWS_PHONE_APP
var tls = new SslStream (stream, false, ValidateRemoteCertificate);
tls.AuthenticateAsClient (uri.Host, ClientCertificates, SslProtocols.Tls, true);
engine.Stream.Stream = tls;
#else
socket.UpgradeToSslAsync (SocketProtectionLevel.Tls12, new HostName (uri.DnsSafeHost))
.AsTask (cancellationToken)
.GetAwaiter ()
.GetResult ();
#endif
// re-issue a CAPA command
engine.QueryCapabilities (cancellationToken);
}
}
/// <summary>
/// Establishes a connection to the specified SMTP or SMTP/S server.
/// </summary>
/// <remarks>
/// <para>Establishes a connection to the specified SMTP or SMTP/S server.</para>
/// <para>If the <paramref name="port"/> has a value of <c>0</c>, then the
/// <paramref name="options"/> parameter is used to determine the default port to
/// connect to. The default port used with <see cref="SecureSocketOptions.SslOnConnect"/>
/// is <c>465</c>. All other values will use a default port of <c>25</c>.</para>
/// <para>If the <paramref name="options"/> has a value of
/// <see cref="SecureSocketOptions.Auto"/>, then the <paramref name="port"/> is used
/// to determine the default security options. If the <paramref name="port"/> has a value
/// of <c>465</c>, then the default options used will be
/// <see cref="SecureSocketOptions.SslOnConnect"/>. All other values will use
/// <see cref="SecureSocketOptions.StartTlsWhenAvailable"/>.</para>
/// <para>Once a connection is established, properties such as
/// <see cref="AuthenticationMechanisms"/> and <see cref="Capabilities"/> will be
/// populated.</para>
/// <para>Note: The connection established by any of the
/// <a href="Overload_MailKit_Net_Smtp_SmtpClient_Connect.htm">Connect</a>
/// methods may be re-used if an application wishes to send multiple messages
/// to the same SMTP server. Since connecting and authenticating can be expensive
/// operations, re-using a connection can significantly improve performance when
/// sending a large number of messages to the same SMTP server over a short
/// period of time.</para>
/// </remarks>
/// <example>
/// <code language="c#" source="Examples\SmtpExamples.cs" region="SendMessage"/>
/// </example>
/// <param name="host">The host name to connect to.</param>
/// <param name="port">The port to connect to. If the specified port is <c>0</c>, then the default port will be used.</param>
/// <param name="options">The secure socket options to when connecting.</param>
/// <param name="cancellationToken">The cancellation token.</param>
/// <exception cref="System.ArgumentNullException">
/// <paramref name="host"/> is <c>null</c>.
/// </exception>
/// <exception cref="System.ArgumentOutOfRangeException">
/// <paramref name="port"/> is not between <c>0</c> and <c>65535</c>.
/// </exception>
/// <exception cref="System.ArgumentException">
/// The <paramref name="host"/> is a zero-length string.
/// </exception>
/// <exception cref="System.ObjectDisposedException">
/// The <see cref="SmtpClient"/> has been disposed.
/// </exception>
/// <exception cref="System.InvalidOperationException">
/// The <see cref="SmtpClient"/> is already connected.
/// </exception>
/// <exception cref="System.NotSupportedException">
/// <paramref name="options"/> was set to
/// <see cref="MailKit.Security.SecureSocketOptions.StartTls"/>
/// and the SMTP server does not support the STARTTLS extension.
/// </exception>
/// <exception cref="System.OperationCanceledException">
/// The operation was canceled.
/// </exception>
/// <exception cref="System.IO.IOException">
/// An I/O error occurred.
/// </exception>
/// <exception cref="SmtpCommandException">
/// An SMTP command failed.
/// </exception>
/// <exception cref="SmtpProtocolException">
/// An SMTP protocol error occurred.
/// </exception>
public override void Connect (string host, int port = 0, SecureSocketOptions options = SecureSocketOptions.Auto, CancellationToken cancellationToken = default (CancellationToken))
{
if (host == null)
throw new ArgumentNullException ("host");
if (host.Length == 0)
throw new ArgumentException ("The host name cannot be empty.", "host");
if (port < 0 || port > 65535)
throw new ArgumentOutOfRangeException ("port");
CheckDisposed ();
if (IsConnected)
throw new InvalidOperationException ("The SmtpClient is already connected.");
capabilities = SmtpCapabilities.None;
AuthenticationMechanisms.Clear ();
MaxSize = 0;
SmtpResponse response;
Stream stream;
bool starttls;
Uri uri;
ComputeDefaultValues (host, ref port, ref options, out uri, out starttls);
#if !NETFX_CORE
var ipAddresses = Dns.GetHostAddresses (host);
Socket socket = null;
for (int i = 0; i < ipAddresses.Length; i++) {
socket = new Socket (ipAddresses[i].AddressFamily, SocketType.Stream, ProtocolType.Tcp);
try {
cancellationToken.ThrowIfCancellationRequested ();
if (LocalEndPoint != null)
socket.Bind (LocalEndPoint);
socket.Connect (ipAddresses[i], port);
break;
} catch (OperationCanceledException) {
socket.Dispose ();
socket = null;
throw;
} catch {
socket.Dispose ();
socket = null;
if (i + 1 == ipAddresses.Length)
throw;
}
}
if (socket == null)
throw new IOException (string.Format ("Failed to resolve host: {0}", host));
this.host = host;
if (options == SecureSocketOptions.SslOnConnect) {
var ssl = new SslStream (new NetworkStream (socket, true), false, ValidateRemoteCertificate);
ssl.AuthenticateAsClient (host, ClientCertificates, SslProtocols, true);
stream = ssl;
} else {
stream = new NetworkStream (socket, true);
}
#else
var protection = options == SecureSocketOptions.SslOnConnect ? SocketProtectionLevel.Tls12 : SocketProtectionLevel.PlainSocket;
var socket = new StreamSocket ();
try {
cancellationToken.ThrowIfCancellationRequested ();
socket.ConnectAsync (new HostName (host), port.ToString (), protection)
.AsTask (cancellationToken)
.GetAwaiter ()
.GetResult ();
} catch {
socket.Dispose ();
throw;
}
stream = new DuplexStream (socket.InputStream.AsStreamForRead (0), socket.OutputStream.AsStreamForWrite (0));
#endif
if (stream.CanTimeout) {
stream.WriteTimeout = timeout;
stream.ReadTimeout = timeout;
}
ProtocolLogger.LogConnect (uri);
Stream = new SmtpStream (stream, socket, ProtocolLogger);
try {
// read the greeting
response = Stream.ReadResponse (cancellationToken);
if (response.StatusCode != SmtpStatusCode.ServiceReady)
throw new SmtpCommandException (SmtpErrorCode.UnexpectedStatusCode, response.StatusCode, response.Response);
// Send EHLO and get a list of supported extensions
Ehlo (cancellationToken);
if (options == SecureSocketOptions.StartTls && (capabilities & SmtpCapabilities.StartTLS) == 0)
throw new NotSupportedException ("The SMTP server does not support the STARTTLS extension.");
if (starttls && (capabilities & SmtpCapabilities.StartTLS) != 0) {
response = SendCommand ("STARTTLS", cancellationToken);
if (response.StatusCode != SmtpStatusCode.ServiceReady)
throw new SmtpCommandException (SmtpErrorCode.UnexpectedStatusCode, response.StatusCode, response.Response);
#if !NETFX_CORE
var tls = new SslStream (stream, false, ValidateRemoteCertificate);
tls.AuthenticateAsClient (host, ClientCertificates, SslProtocols, true);
Stream.Stream = tls;
#else
socket.UpgradeToSslAsync (SocketProtectionLevel.Tls12, new HostName (host))
.AsTask (cancellationToken)
.GetAwaiter ()
.GetResult ();
#endif
// Send EHLO again and get the new list of supported extensions
Ehlo (cancellationToken);
}
connected = true;
} catch {
Stream.Dispose ();
Stream = null;
throw;
}
OnConnected ();
}
/// <summary>
/// Establish a connection to the specified IMAP server.
/// </summary>
/// <remarks>
/// <para>Establishes a connection to the specified IMAP or IMAP/S server.</para>
/// <para>If the <paramref name="port"/> has a value of <c>0</c>, then the
/// <paramref name="options"/> parameter is used to determine the default port to
/// connect to. The default port used with <see cref="SecureSocketOptions.SslOnConnect"/>
/// is <c>993</c>. All other values will use a default port of <c>143</c>.</para>
/// <para>If the <paramref name="options"/> has a value of
/// <see cref="SecureSocketOptions.Auto"/>, then the <paramref name="port"/> is used
/// to determine the default security options. If the <paramref name="port"/> has a value
/// of <c>993</c>, then the default options used will be
/// <see cref="SecureSocketOptions.SslOnConnect"/>. All other values will use
/// <see cref="SecureSocketOptions.StartTlsWhenAvailable"/>.</para>
/// <para>Once a connection is established, properties such as
/// <see cref="AuthenticationMechanisms"/> and <see cref="Capabilities"/> will be
/// populated.</para>
/// </remarks>
/// <example>
/// <code language="c#" source="Examples\ImapExamples.cs" region="DownloadMessages"/>
/// </example>
/// <param name="host">The host name to connect to.</param>
/// <param name="port">The port to connect to. If the specified port is <c>0</c>, then the default port will be used.</param>
/// <param name="options">The secure socket options to when connecting.</param>
/// <param name="cancellationToken">The cancellation token.</param>
/// <exception cref="System.ArgumentNullException">
/// <paramref name="host"/> is <c>null</c>.
/// </exception>
/// <exception cref="System.ArgumentOutOfRangeException">
/// <paramref name="port"/> is not between <c>0</c> and <c>65535</c>.
/// </exception>
/// <exception cref="System.ArgumentException">
/// The <paramref name="host"/> is a zero-length string.
/// </exception>
/// <exception cref="System.ObjectDisposedException">
/// The <see cref="ImapClient"/> has been disposed.
/// </exception>
/// <exception cref="System.InvalidOperationException">
/// The <see cref="ImapClient"/> is already connected.
/// </exception>
/// <exception cref="System.NotSupportedException">
/// <paramref name="options"/> was set to
/// <see cref="MailKit.Security.SecureSocketOptions.StartTls"/>
/// and the IMAP server does not support the STARTTLS extension.
/// </exception>
/// <exception cref="System.OperationCanceledException">
/// The operation was canceled via the cancellation token.
/// </exception>
/// <exception cref="System.IO.IOException">
/// An I/O error occurred.
/// </exception>
/// <exception cref="ImapProtocolException">
/// An IMAP protocol error occurred.
/// </exception>
public override void Connect (string host, int port = 0, SecureSocketOptions options = SecureSocketOptions.Auto, CancellationToken cancellationToken = default (CancellationToken))
{
if (host == null)
throw new ArgumentNullException ("host");
if (host.Length == 0)
throw new ArgumentException ("The host name cannot be empty.", "host");
if (port < 0 || port > 65535)
throw new ArgumentOutOfRangeException ("port");
CheckDisposed ();
if (IsConnected)
throw new InvalidOperationException ("The ImapClient is already connected.");
Stream stream;
bool starttls;
Uri uri;
ComputeDefaultValues (host, ref port, ref options, out uri, out starttls);
#if !NETFX_CORE
var ipAddresses = Dns.GetHostAddresses (host);
Socket socket = null;
for (int i = 0; i < ipAddresses.Length; i++) {
socket = new Socket (ipAddresses[i].AddressFamily, SocketType.Stream, ProtocolType.Tcp);
try {
cancellationToken.ThrowIfCancellationRequested ();
socket.Connect (ipAddresses[i], port);
break;
} catch (OperationCanceledException) {
socket.Dispose ();
throw;
} catch {
socket.Dispose ();
if (i + 1 == ipAddresses.Length)
throw;
}
}
if (socket == null)
throw new IOException (string.Format ("Failed to resolve host: {0}", host));
engine.Uri = uri;
if (options == SecureSocketOptions.SslOnConnect) {
var ssl = new SslStream (new NetworkStream (socket, true), false, ValidateRemoteCertificate);
ssl.AuthenticateAsClient (host, ClientCertificates, DefaultSslProtocols, true);
stream = ssl;
} else {
stream = new NetworkStream (socket, true);
}
#else
var protection = options == SecureSocketOptions.SslOnConnect ? SocketProtectionLevel.Tls12 : SocketProtectionLevel.PlainSocket;
socket = new StreamSocket ();
try {
cancellationToken.ThrowIfCancellationRequested ();
socket.ConnectAsync (new HostName (host), port.ToString (), protection)
.AsTask (cancellationToken)
.GetAwaiter ()
.GetResult ();
} catch {
socket.Dispose ();
socket = null;
throw;
}
stream = new DuplexStream (socket.InputStream.AsStreamForRead (0), socket.OutputStream.AsStreamForWrite (0));
engine.Uri = uri;
#endif
if (stream.CanTimeout) {
stream.WriteTimeout = timeout;
stream.ReadTimeout = timeout;
}
ProtocolLogger.LogConnect (uri);
engine.Connect (new ImapStream (stream, socket, ProtocolLogger), cancellationToken);
try {
// Only query the CAPABILITIES if the greeting didn't include them.
if (engine.CapabilitiesVersion == 0)
engine.QueryCapabilities (cancellationToken);
if (options == SecureSocketOptions.StartTls && (engine.Capabilities & ImapCapabilities.StartTLS) == 0)
throw new NotSupportedException ("The IMAP server does not support the STARTTLS extension.");
if (starttls && (engine.Capabilities & ImapCapabilities.StartTLS) != 0) {
var ic = engine.QueueCommand (cancellationToken, null, "STARTTLS\r\n");
engine.Wait (ic);
if (ic.Response == ImapCommandResponse.Ok) {
#if !NETFX_CORE
var tls = new SslStream (stream, false, ValidateRemoteCertificate);
tls.AuthenticateAsClient (host, ClientCertificates, DefaultSslProtocols, true);
engine.Stream.Stream = tls;
#else
socket.UpgradeToSslAsync (SocketProtectionLevel.Tls12, new HostName (host))
.AsTask (cancellationToken)
.GetAwaiter ()
.GetResult ();
#endif
// Query the CAPABILITIES again if the server did not include an
// untagged CAPABILITIES response to the STARTTLS command.
if (engine.CapabilitiesVersion == 1)
engine.QueryCapabilities (cancellationToken);
} else if (options == SecureSocketOptions.StartTls) {
throw ImapCommandException.Create ("STARTTLS", ic);
}
}
} catch {
engine.Disconnect ();
throw;
}
engine.Disconnected += OnEngineDisconnected;
OnConnected ();
}
/// <summary>
/// Establishes a connection to the specified IMAP server.
/// </summary>
/// <remarks>
/// <para>Establishes a connection to an IMAP or IMAP/S server. If the schema
/// in the uri is "imap", a clear-text connection is made and defaults to using
/// port 143 if no port is specified in the URI. However, if the schema in the
/// uri is "imaps", an SSL connection is made using the
/// <see cref="ClientCertificates"/> and defaults to port 993 unless a port
/// is specified in the URI.</para>
/// <para>It should be noted that when using a clear-text IMAP connection,
/// if the server advertizes support for the STARTTLS extension, the client
/// will automatically switch into TLS mode before authenticating unless the
/// <paramref name="uri"/> contains a query string to disable it.</para>
/// <para>If the IMAP server advertizes the COMPRESS extension and either does not
/// support the STARTTLS extension or the <paramref name="uri"/> explicitly disabled
/// the use of the STARTTLS extension, then the client will automatically opt into
/// using a compressed data connection to optimize bandwidth usage unless the
/// <paramref name="uri"/> contains a query string to explicitly disable it.</para>
/// <para>If a successful connection is made, the <see cref="AuthenticationMechanisms"/>
/// and <see cref="Capabilities"/> properties will be populated.</para>
/// </remarks>
/// <param name="uri">The server URI. The <see cref="System.Uri.Scheme"/> should either
/// be "imap" to make a clear-text connection or "imaps" to make an SSL connection.</param>
/// <param name="cancellationToken">A cancellation token.</param>
/// <exception cref="System.ArgumentNullException">
/// The <paramref name="uri"/> is <c>null</c>.
/// </exception>
/// <exception cref="System.ArgumentException">
/// The <paramref name="uri"/> is not an absolute URI.
/// </exception>
/// <exception cref="System.ObjectDisposedException">
/// The <see cref="ImapClient"/> has been disposed.
/// </exception>
/// <exception cref="System.InvalidOperationException">
/// The <see cref="ImapClient"/> is already connected.
/// </exception>
/// <exception cref="System.OperationCanceledException">
/// The operation was canceled via the cancellation token.
/// </exception>
/// <exception cref="System.IO.IOException">
/// An I/O error occurred.
/// </exception>
/// <exception cref="ImapProtocolException">
/// An IMAP protocol error occurred.
/// </exception>
public void Connect(Uri uri, CancellationToken cancellationToken)
{
CheckDisposed ();
if (uri == null)
throw new ArgumentNullException ("uri");
if (!uri.IsAbsoluteUri)
throw new ArgumentException ("The uri must be absolute.", "uri");
if (IsConnected)
throw new InvalidOperationException ("The ImapClient is already connected.");
var imaps = uri.Scheme.ToLowerInvariant () == "imaps";
var port = uri.Port > 0 ? uri.Port : (imaps ? 993 : 143);
var query = uri.ParsedQuery ();
Stream stream;
string value;
var starttls = !imaps && (!query.TryGetValue ("starttls", out value) || Convert.ToBoolean (value));
var compress = !imaps && (!query.TryGetValue ("compress", out value) || Convert.ToBoolean (value));
#if !NETFX_CORE
var ipAddresses = Dns.GetHostAddresses (uri.DnsSafeHost);
Socket socket = null;
for (int i = 0; i < ipAddresses.Length; i++) {
socket = new Socket (ipAddresses[i].AddressFamily, SocketType.Stream, ProtocolType.Tcp);
cancellationToken.ThrowIfCancellationRequested ();
try {
socket.Connect (ipAddresses[i], port);
break;
} catch {
if (i + 1 == ipAddresses.Length)
throw;
}
}
if (imaps) {
var ssl = new SslStream (new NetworkStream (socket, true), false, ValidateRemoteCertificate);
ssl.AuthenticateAsClient (uri.Host, ClientCertificates, SslProtocols.Default, true);
stream = ssl;
} else {
stream = new NetworkStream (socket, true);
}
#else
socket = new StreamSocket ();
cancellationToken.ThrowIfCancellationRequested ();
socket.ConnectAsync (new HostName (uri.DnsSafeHost), port.ToString (), imaps ? SocketProtectionLevel.Tls12 : SocketProtectionLevel.PlainSocket)
.AsTask (cancellationToken)
.GetAwaiter ()
.GetResult ();
stream = new DuplexStream (socket.InputStream.AsStreamForRead (), socket.OutputStream.AsStreamForWrite ());
#endif
host = uri.Host;
logger.LogConnect (uri);
engine.Connect (new ImapStream (stream, logger), cancellationToken);
// Only query the CAPABILITIES if the greeting didn't include them.
if (engine.CapabilitiesVersion == 0)
engine.QueryCapabilities (cancellationToken);
if (starttls && (engine.Capabilities & ImapCapabilities.StartTLS) != 0) {
var ic = engine.QueueCommand (cancellationToken, null, "STARTTLS\r\n");
engine.Wait (ic);
if (ic.Result == ImapCommandResult.Ok) {
#if !NETFX_CORE
var tls = new SslStream (stream, false, ValidateRemoteCertificate);
tls.AuthenticateAsClient (uri.Host, ClientCertificates, SslProtocols.Tls, true);
engine.Stream.Stream = tls;
#else
socket.UpgradeToSslAsync (SocketProtectionLevel.Tls12, new HostName (uri.DnsSafeHost))
.AsTask (cancellationToken)
.GetAwaiter ()
.GetResult ();
#endif
// Query the CAPABILITIES again if the server did not include an
// untagged CAPABILITIES response to the STARTTLS command.
if (engine.CapabilitiesVersion == 1)
engine.QueryCapabilities (cancellationToken);
}
} else if (compress && (engine.Capabilities & ImapCapabilities.Compress) != 0) {
var ic = engine.QueueCommand (cancellationToken, null, "COMPRESS DEFLATE\r\n");
engine.Wait (ic);
if (ic.Result == ImapCommandResult.Ok) {
var unzip = new DeflateStream (stream, CompressionMode.Decompress);
var zip = new DeflateStream (stream, CompressionMode.Compress);
engine.Stream.Stream = new DuplexStream (unzip, zip);
// Query the CAPABILITIES again if the server did not include an
// untagged CAPABILITIES response to the COMPRESS command.
if (engine.CapabilitiesVersion == 1)
engine.QueryCapabilities (cancellationToken);
}
}
}
//------------------------------------------------------------------------------------------------------------------------
SimpleActionResult _sockConnection(string RemoteHost, int RemotePort)
{
//declares
bool isSecured = false;
string sslProtocol = "";
var result = new SimpleActionResult()
{
IsSuccessful = false,
Message = "",
};
lock (this)
{
//create socket
#if NETFX
_sock = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
#elif UNIVERSAL
_sock = new StreamSocket();
#endif
//Try to connect
try
{
//attemp connection
#if NETFX
_sock.Connect(RemoteHost, RemotePort);
#elif UNIVERSAL
SocketSetup?.Invoke(this, _sock);
_sock.Control.KeepAlive = true;
_sock.ConnectAsync(new Windows.Networking.HostName(RemoteHost), RemotePort.ToStringInvariant(), SocketProtectionLevel.PlainSocket).AsTask().Wait();
#endif
}
catch (Exception ex)
{
DebugEx.TraceError(ex, "Connection Error");
result.Message = ex.Message;
try { Close("Connection Error"); } catch { }
return result;
}
//create network stream
#if NETFX
//Stream _netstream = new BufferedStream(new NetworkStream(_sock, true));
Stream _netstream = new NetworkStream(_sock, true);
#endif
//Wrap with a secure stream?
if (Secure)
{
#if NETFX
//create ssl stream
var sslstream = new SslStream(_netstream, false);
#endif
//decide on certifacte server name
var remCertHostName = !string.IsNullOrWhiteSpace(CertificateServerName) ? CertificateServerName : RemoteHost;
try
{
#if NETFX
//collect certificates
var certs = Yodiwo.Tools.Certificates.CollectCertificates();
if (CustomCertificates != null)
foreach (var c in CustomCertificates)
certs.Add(c);
//try authenticate
sslstream.AuthenticateAsClient(remCertHostName,
certs,
System.Security.Authentication.SslProtocols.Tls | System.Security.Authentication.SslProtocols.Tls11 | System.Security.Authentication.SslProtocols.Tls12,
true
);
//checks
if (!sslstream.IsAuthenticated)
{
DebugEx.Assert("Not authenticated");
throw new Exception("Not authenticated");
}
if (!sslstream.IsEncrypted)
{
DebugEx.Assert("No encryption");
throw new Exception("Not encryption");
}
//get info
isSecured = true;
sslProtocol = sslstream.SslProtocol.ToStringInvariant();
//use this stream from now on
_netstream = sslstream;
#elif UNIVERSAL
_sock.UpgradeToSslAsync(SocketProtectionLevel.Tls12, new Windows.Networking.HostName(remCertHostName)).AsTask().Wait();
var _isSecured = _sock.Information.ProtectionLevel == SocketProtectionLevel.Tls10 ||
_sock.Information.ProtectionLevel == SocketProtectionLevel.Tls11 ||
_sock.Information.ProtectionLevel == SocketProtectionLevel.Tls12;
if (!_isSecured)
throw new Exception("Connection not secured (" + _sock.Information.ProtectionLevel + ")");
#endif
}
catch (Exception ex)
{
DebugEx.TraceError(ex, "Certificate not accepted, " + ex.Message);
result.Message = "Certificate not accepted, " + ex.Message;
if (ex.InnerException != null)
result.Message += " (inner msg=" + ex.InnerException.Message + ")";
try { Close("Certificate not accepted, " + ex.Message); } catch { }
#if NETFX
try { _netstream?.Close(); _netstream?.Dispose(); } catch { }
try { sslstream?.Close(); sslstream?.Dispose(); } catch { }
try { _sock?.Close(); } catch { }
#endif
try { _sock?.Dispose(); } catch { }
return result;
}
}
//write packers
#if NETFX
var _nodelay = _sock.NoDelay;
_sock.NoDelay = true; //Disable the Nagle Algorithm
_netstream.WriteByte((byte)this.SupportedChannelSerializationModes);
_netstream.WriteByte((byte)this.PreferredChannelSerializationModes);
_sock.NoDelay = _nodelay; //Restore (default:enable) the Nagle Algorithm
#elif UNIVERSAL
{
var wStream = _sock.OutputStream.AsStreamForWrite();
wStream.WriteByte((byte)this.SupportedChannelSerializationModes);
wStream.WriteByte((byte)this.PreferredChannelSerializationModes);
wStream.Flush();
}
#endif
//read final packer
var packerType = ChannelSerializationMode.Unkown;
#if NETFX
packerType = (ChannelSerializationMode)_netstream.ReadByte();
#elif UNIVERSAL
packerType = (ChannelSerializationMode)_sock.InputStream.AsStreamForRead().ReadByte();
#endif
if (!this.SupportedChannelSerializationModes.HasFlag(packerType))
{
DebugEx.Assert("Invalid ChannelSerializationMode. Server uses " + packerType);
result.Message = "Invalid ChannelSerializationMode. Server uses " + packerType;
try { Close("Invalid ChannelSerializationMode. Server uses " + packerType); } catch { }
#if NETFX
try { _netstream?.Close(); _netstream?.Dispose(); } catch { }
try { _sock?.Close(); } catch { }
#endif
try { _sock?.Dispose(); } catch { }
return result;
}
//select serialization mode
_ChannelSerializationMode = packerType;
//setup info
try
{
#if NETFX
this.LocalHost = _sock.LocalEndPoint.GetIPAddress().ToString();
this.RemotePort = _sock.LocalEndPoint.GetPort().ToStringInvariant();
#elif UNIVERSAL
this.LocalHost = _sock.Information.LocalAddress.ToString();
this.RemotePort = _sock.Information.LocalPort;
#endif
}
catch { }
//setup info
this.RemoteHost = RemoteHost;
this.RemotePort = RemotePort.ToStringInvariant();
//log
DebugEx.TraceLog("YPClient (socks) new connection to " + RemoteHost + ":" + RemotePort + " (Secure=" + isSecured + ",SSL=" + sslProtocol + ")");
//create stream
#if NETFX
SetupStream(_netstream);
#elif UNIVERSAL
SetupStream();
#endif
result.IsSuccessful = true;
return result;
}
}