ASP.NET Tutorial/Development/Cryptography
Cryptography.SHA1Managed
<source lang="csharp">
<%@ Page %> <script Language="vb" runat="server"> Private Sub Page_Load(sender As Object, e As System.EventArgs)
Dim clearText As String = "Try not. Do. Or do not. There is no try."
Dim encoder As New System.Text.UTF8Encoding()
Response.Write(("Clear Text: " + clearText))
Response.Write("")
Dim sha As New System.Security.Cryptography.SHA1Managed()
Dim input As Byte() = encoder.GetBytes(clearText)
Dim output As Byte() = sha.ruputeHash(input)
Response.Write(("Encrypted Text: " + encoder.GetString(output)))
End Sub </script></source>
Decrypt / Encrypt
<source lang="csharp">
<%@ Page Language="VB" AutoEventWireup="false" CodeFile="Default.aspx.vb" Inherits="Default_aspx" %> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd"> <html xmlns="http://www.w3.org/1999/xhtml" > <head runat="server">
<title>Untitled Page</title>
</head> <body>
<form id="form1" runat="server">
<asp:GridView ID="GridView1" runat="server" DataSourceID="SqlDataSource1" AutoGenerateColumns="False"
DataKeyNames="au_id">
<Columns>
<asp:BoundField DataField="au_id" HeaderText="au_id" ReadOnly="True" SortExpression="au_id" />
<asp:BoundField DataField="au_lname" HeaderText="au_lname" SortExpression="au_lname" />
<asp:BoundField DataField="au_fname" HeaderText="au_fname" SortExpression="au_fname" />
<asp:BoundField DataField="phone" HeaderText="phone" SortExpression="phone" />
<asp:BoundField DataField="address" HeaderText="address" SortExpression="address" />
<asp:BoundField DataField="city" HeaderText="city" SortExpression="city" />
<asp:BoundField DataField="state" HeaderText="state" SortExpression="state" />
<asp:BoundField DataField="zip" HeaderText="zip" SortExpression="zip" />
<asp:CheckBoxField DataField="contract" HeaderText="contract" SortExpression="contract" />
</Columns>
</asp:GridView>
<asp:SqlDataSource ID="SqlDataSource1" runat="server" ConnectionString="<%$ ConnectionStrings:pubsConnectionString %>"
SelectCommand="SELECT * FROM [authors]"></asp:SqlDataSource>
</form>
</body> </html> File: Default.aspx.vb Imports System.Configuration "Imports System.Web "Imports System.Web.Security Imports System.Web.Security Partial Class Default_aspx
Inherits System.Web.UI.Page
Protected Sub Page_Load(ByVal sender As Object, _
ByVal e As System.EventArgs) _
Handles Me.Load
"Encrypt("DataProtectionConfigurationProvider")
"--or--
Decrypt()
"Encrypt("RSAProtectedConfigurationProvider")
" Decrypt()
"AddConnString()
"---retrieve the newly added string
Dim connect As String = _
ConfigurationManager.ConnectionStrings _
("PubsConnectionString").ConnectionString
Response.Write(connect)
End Sub
Public Sub Encrypt(ByVal protectionProvider As String)
Dim config As Configuration = _
System.Web.Configuration.WebConfigurationManager.OpenWebConfiguration( _
Request.ApplicationPath)
Dim section As ConfigurationSection = config.Sections("connectionStrings")
If Not section.SectionInformation.IsProtected Then
section.SectionInformation.ProtectSection(protectionProvider)
config.Save()
End If
End Sub
Public Sub Decrypt()
Dim config As Configuration = System.Web.Configuration.WebConfigurationManager.OpenWebConfiguration( _
Request.ApplicationPath)
Dim section As ConfigurationSection = config.Sections("connectionStrings")
section.SectionInformation.UnProtectSection()
config.Save()
End Sub
Public Sub AddConnString()
Dim config As Configuration = System.Web.Configuration.WebConfigurationManager.OpenWebConfiguration( _
Request.ApplicationPath)
config.ConnectionStrings.ConnectionStrings.Add _
(New ConnectionStringSettings("NorthwindConnectionString", _
"server=localhost;database=northwind;integrated security=true"))
config.Save()
End Sub
End Class</source>
Generate Keys
<source lang="csharp">
<%@ Page Language="C#" %> <%@ Import Namespace="System.Security.Cryptography" %> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <script runat="server">
void Page_Load()
{
lblAES.Text = GetSequence(64);
lblSHA1.Text = GetSequence(128);
}
private string GetSequence(int length)
{
byte[] buffer = new byte[length/2];
RNGCryptoServiceProvider provider = new RNGCryptoServiceProvider();
provider.GetBytes(buffer);
StringBuilder builder = new StringBuilder(length);
for (int i = 0; i < buffer.Length; i++)
builder.Append(string.Format("{0:X2}", buffer[i]));
return builder.ToString();
}
</script> <html xmlns="http://www.w3.org/1999/xhtml" > <head id="Head1" runat="server">
<title>Generate Keys</title>
</head> <body>
<form id="form1" runat="server">
AES:
<asp:Label
id="lblAES"
Runat="server" />
SHA1:
<asp:Label
id="lblSHA1"
Runat="server" />
</form>
</body> </html></source>
