Skip to content

Commit b2cb36b

Browse files
arjanvanhuizenRon Petrusha
arjanvanhuizen
authored and
Ron Petrusha
committed
VB sample added (#735)
* VB sample added * Update serversync.vb
1 parent e5bb7b6 commit b2cb36b

File tree

1 file changed

+177
-0
lines changed
  • snippets/visualbasic/VS_Snippets_Remoting/NclSslServerSync/VB

1 file changed

+177
-0
lines changed

‎snippets/visualbasic/VS_Snippets_Remoting/NclSslServerSync/VB/serversync.vb‎

Lines changed: 177 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,177 @@
1+
' NclSslServerSync
2+
3+
' <snippet0>
4+
Imports System.Collections
5+
Imports System.Net
6+
Imports System.Net.Sockets
7+
Imports System.Net.Security
8+
Imports System.Security.Authentication
9+
Imports System.Text
10+
Imports System.Security.Cryptography.X509Certificates
11+
Imports System.IO
12+
13+
Namespace Examples.System.Net
14+
Public NotInheritable Class SslTcpServer
15+
Shared serverCertificate As X509Certificate = Nothing
16+
17+
' The certificate parameter specifies the name of the file
18+
' containing the machine certificate.
19+
Public Shared Sub RunServer(certificate As String)
20+
serverCertificate = X509Certificate.CreateFromCertFile(certificate)
21+
' Create a TCP/IP (IPv4) socket And listen for incoming connections.
22+
Dim listener = New TcpListener(IPAddress.Any, 8080)
23+
listener.Start()
24+
25+
While True
26+
Console.WriteLine("Waiting for a client to connect...")
27+
' Application blocks while waiting for an incoming connection.
28+
' Type CNTL-C to terminate the server.
29+
Dim client As TcpClient = listener.AcceptTcpClient()
30+
ProcessClient(client)
31+
End While
32+
End Sub
33+
'<snippet1
34+
Private Shared Sub ProcessClient(client As TcpClient)
35+
' A client has connected. Create the
36+
' SslStream using the client's network stream.
37+
Dim sslStream = New SslStream(client.GetStream(), False)
38+
39+
Try
40+
41+
sslStream.AuthenticateAsServer(serverCertificate, clientCertificateRequired:=False, checkCertificateRevocation:=True)
42+
' Display the properties And settings for the authenticated stream.
43+
DisplaySecurityLevel(sslStream)
44+
DisplaySecurityServices(sslStream)
45+
DisplayCertificateInformation(sslStream)
46+
DisplayStreamProperties(sslStream)
47+
48+
' Set timeouts for the read and write to 5 seconds.
49+
sslStream.ReadTimeout = 5000
50+
sslStream.WriteTimeout = 5000
51+
52+
' Read a message from the client.
53+
Console.WriteLine("Waiting for client message...")
54+
Dim messageData As String = ReadMessage(sslStream)
55+
Console.WriteLine("Received: {0}", messageData)
56+
57+
' Write a message to the client.
58+
Dim message As Byte() = Encoding.UTF8.GetBytes("Hello from the server.<EOF>")
59+
Console.WriteLine("Sending hello message.")
60+
sslStream.Write(message)
61+
Catch e As AuthenticationException
62+
Console.WriteLine("Exception: {0}", e.Message)
63+
64+
If e.InnerException IsNot Nothing Then
65+
Console.WriteLine("Inner exception: {0}", e.InnerException.Message)
66+
End If
67+
68+
Console.WriteLine("Authentication failed - closing the connection.")
69+
sslStream.Close()
70+
client.Close()
71+
Return
72+
Finally
73+
' The client stream will be closed with the sslStream
74+
' because we specified this behavior when creating
75+
' the sslStream.
76+
sslStream.Close()
77+
client.Close()
78+
End Try
79+
End Sub
80+
81+
'</snippet1>
82+
'<snippet2>
83+
Private Shared Function ReadMessage(sslStream As SslStream) As String
84+
85+
' Read the message sent by the client.
86+
' The client signals the end of the message using the
87+
' "<EOF>" marker.
88+
Dim buffer As Byte() = New Byte(2048) {}
89+
Dim messageData As StringBuilder = New StringBuilder()
90+
Dim bytes As Integer = -1
91+
92+
Do
93+
' Read the client's test message.
94+
bytes = sslStream.Read(buffer, 0, buffer.Length)
95+
96+
' Use decoder class to convert from bytes to UTF8
97+
' in case a character spans two buffers.
98+
Dim decoder As Decoder = Encoding.UTF8.GetDecoder()
99+
Dim chars As Char() = New Char(decoder.GetCharCount(buffer, 0, bytes) - 1) {}
100+
decoder.GetChars(buffer, 0, bytes, chars, 0)
101+
messageData.Append(chars)
102+
103+
' Check for EOF or an empty message.
104+
If messageData.ToString().IndexOf("<EOF>") <> -1 Then
105+
Exit Do
106+
End If
107+
Loop While bytes <> 0
108+
109+
Return messageData.ToString()
110+
End Function
111+
112+
' </snippet2>
113+
' <snippet3>
114+
Private Shared Sub DisplaySecurityLevel(stream As SslStream)
115+
Console.WriteLine("Cipher: {0} strength {1}", stream.CipherAlgorithm, stream.CipherStrength)
116+
Console.WriteLine("Hash: {0} strength {1}", stream.HashAlgorithm, stream.HashStrength)
117+
Console.WriteLine("Key exchange: {0} strength {1}", stream.KeyExchangeAlgorithm, stream.KeyExchangeStrength)
118+
Console.WriteLine("Protocol: {0}", stream.SslProtocol)
119+
End Sub
120+
'</snippet3>
121+
'<snippet4>
122+
123+
Private Shared Sub DisplaySecurityServices(stream As SslStream)
124+
Console.WriteLine("Is authenticated: {0} as server? {1}", stream.IsAuthenticated, stream.IsServer)
125+
Console.WriteLine("IsSigned: {0}", stream.IsSigned)
126+
Console.WriteLine("Is Encrypted: {0}", stream.IsEncrypted)
127+
End Sub
128+
' </snippet4>
129+
' <snippet5>
130+
Private Shared Sub DisplayStreamProperties(stream As SslStream)
131+
Console.WriteLine("Can read: {0}, write {1}", stream.CanRead, stream.CanWrite)
132+
Console.WriteLine("Can timeout: {0}", stream.CanTimeout)
133+
End Sub
134+
135+
' </snippet5>
136+
' <snippet6>
137+
Private Shared Sub DisplayCertificateInformation(stream As SslStream)
138+
Console.WriteLine("Certificate revocation list checked: {0}", stream.CheckCertRevocationStatus)
139+
Dim localCertificate As X509Certificate = stream.LocalCertificate
140+
141+
If stream.LocalCertificate IsNot Nothing Then
142+
Console.WriteLine("Local cert was issued to {0} and is valid from {1} until {2}.", localCertificate.Subject, localCertificate.GetEffectiveDateString(), localCertificate.GetExpirationDateString())
143+
Else
144+
Console.WriteLine("Local certificate is null.")
145+
End If
146+
147+
' Display the properties of the client's certificate.
148+
Dim remoteCertificate As X509Certificate = stream.RemoteCertificate
149+
150+
If stream.RemoteCertificate IsNot Nothing Then
151+
Console.WriteLine("Remote cert was issued to {0} and is valid from {1} until {2}.", remoteCertificate.Subject, remoteCertificate.GetEffectiveDateString(), remoteCertificate.GetExpirationDateString())
152+
Else
153+
Console.WriteLine("Remote certificate is null.")
154+
End If
155+
End Sub
156+
157+
' </snippet6>
158+
Private Shared Sub DisplayUsage()
159+
Console.WriteLine("To start the server specify:")
160+
Console.WriteLine("serverSync certificateFile.cer")
161+
Environment.[Exit](1)
162+
End Sub
163+
164+
Public Shared Function Main(ByVal args As String()) As Integer
165+
Dim certificate As String
166+
167+
If args Is Nothing OrElse args.Length < 1 Then
168+
DisplayUsage()
169+
End If
170+
171+
certificate = args(0)
172+
RunServer(certificate)
173+
Return 0
174+
End Function
175+
End Class
176+
End Namespace
177+
'</snippet0>

0 commit comments

Comments
 (0)