RSA code: Difference between revisions

=={{header|Visual Basic .NET}}==

{{trans|C#}}

{{libheader|System.Numerics}}

<lang vbnet>Imports System

Imports System.Numerics

Imports System.Text

Module Module1

Sub Main()

Dim n As BigInteger = BigInteger.Parse("9516311845790656153499716760847001433441357")

Dim e As BigInteger = 65537

Dim d As BigInteger = BigInteger.Parse("5617843187844953170308463622230283376298685")

Dim plainTextStr As String = "Hello, Rosetta!"

Dim plainTextBA As Byte() = ASCIIEncoding.ASCII.GetBytes(plainTextStr)

Dim pt As BigInteger = New BigInteger(plainTextBA)

If pt > n Then Throw New Exception() ' Blocking not implemented

Dim ct As BigInteger = BigInteger.ModPow(pt, e, n)

Console.WriteLine(" Encoded: " & ct.ToString("X"))

Dim dc As BigInteger = BigInteger.ModPow(ct, d, n)

Console.WriteLine(" Decoded: " & dc.ToString("X"))

Dim decoded As String = ASCIIEncoding.ASCII.GetString(dc.ToByteArray())

Console.WriteLine("As ASCII: " & decoded)

End Sub

End Module</lang>

{{out}}

<pre> Encoded: 6219A470D8B319A31C8E13F612B31337098F

Decoded: 2161747465736F52202C6F6C6C6548

As ASCII: Hello, Rosetta!</pre>