Implementasi Super Enkripsi Algoritma Elgamal Dengan Teknik Transposisi Segitiga

A-1
LISTING PROGRAM

1. Listing Program untuk Mainform
Public Class Form1
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles
MyBase.Load
Infragistics.Win.AppStyling.StyleManager.Load("MyStyleSet3.isl")
Timer1.Start()
End Sub
Private Sub UltraToolbarsManager1_ToolClick(ByVal sender As System.Object, ByVal e As
Infragistics.Win.UltraWinToolbars.ToolClickEventArgs) Handles UltraToolbarsManager1.ToolClick
If (e.Tool.Key = "Encryption") Then
Dim ctrl As New EncryptControl
UltraPanel1.ClientArea.Controls.Clear()
UltraPanel1.ClientArea.Controls.Add(ctrl)
UltraStatusBar1.Panels(0).Text = e.Tool.Key
ElseIf (e.Tool.Key = "Decryption") Then
Dim ctrl As New DecryptControl
UltraPanel1.ClientArea.Controls.Clear()
UltraPanel1.ClientArea.Controls.Add(ctrl)

UltraStatusBar1.Panels(0).Text = e.Tool.Key
ElseIf (e.Tool.Key = "Help") Then
System.Diagnostics.Process.Start(Application.StartupPath & "\HelpSystem.chm")
ElseIf (e.Tool.Key = "About") Then
Dim ctrl As New AboutForm
ctrl.ShowDialog()
UltraStatusBar1.Panels(0).Text = e.Tool.Key
ElseIf (e.Tool.Key = "Light") Then
Infragistics.Win.AppStyling.StyleManager.Load("MyStyleSet2.isl")
ElseIf (e.Tool.Key = "Dark") Then
Infragistics.Win.AppStyling.StyleManager.Load("MyStyleSet.isl")
ElseIf (e.Tool.Key = "Purple") Then
Infragistics.Win.AppStyling.StyleManager.Load("MyStyleSet3.isl")
ElseIf (e.Tool.Key = "Exit") Then
Me.Close()
End If
End Sub
Private Sub Timer1_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles
Timer1.Tick
UltraStatusBar1.Panels(1).Text = Date.Now.ToString("dddd, d-MMMM-yyyy hh:mm:ss tt")

End Sub
Private Sub Form1_FormClosing(ByVal sender As System.Object, ByVal e As
System.Windows.Forms.FormClosingEventArgs) Handles MyBase.FormClosing

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If (MessageBox.Show("Exit Application?", "Exit?", MessageBoxButtons.YesNo,
MessageBoxIcon.Question) = DialogResult.No) Then
e.Cancel = True
Else
Dim frm = Application.OpenForms("SplashScreen")
frm.Close()
End If
End Sub
End Class

2. Listing Program untuk Form Encrypt
Imports System.Numerics
Imports System.IO

Imports Infragistics.Win.UltraWinGrid
Imports System.Diagnostics
Public Class EncryptControl
Private isLarge As Boolean = False
Private Sub txtPlaintext_ValueChanged(ByVal sender As System.Object, ByVal e As
System.EventArgs) Handles txtPlaintext.ValueChanged
lblChar.Text = ": " & txtPlaintext.TextLength & " Char"
End Sub
Private Function checkKey() As Boolean
Dim retValue As Boolean = True
For Each ctrl In UltraGroupBox3.Controls
If TypeName(ctrl) = "UltraTextEditor" Then
If ctrl.Text = "" Then
retValue = False
End If
End If
Next
Return retValue
End Function
Private Sub btnEncrypt_Click(ByVal sender As System.Object, ByVal e As System.EventArgs)

Handles btnEncrypt.Click
If (txtPlaintext.Text = "") Then
MessageBox.Show("Input your Plaintext!", "Encrypt Error", MessageBoxButtons.OK,
MessageBoxIcon.Error)
txtPlaintext.Focus()
Exit Sub
ElseIf (Not checkKey()) Then
MessageBox.Show("Your Key is missing!", "Encrypt Error", MessageBoxButtons.OK,
MessageBoxIcon.Error)
txtPrime.Focus()
Exit Sub

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End If
Dim EncryptTime As Stopwatch = New Stopwatch()
Dim time As String = ""
EncryptTime.Start()
ciphertext = ""

Dim trans As Transpose = New Transpose
txtTransCipher.Text = trans.TransposeEncrypt(txtPlaintext.Text)
TriGrid.DataSource = trans.getTriangle()
TriGrid.DisplayLayout.Override.DefaultColWidth = 25
TriGrid.DisplayLayout.Override.HeaderClickAction = HeaderClickAction.Select
TriGrid.DisplayLayout.Override.SelectTypeCol = SelectType.None
TriGrid.DisplayLayout.Override.CellClickAction = CellClickAction.RowSelect
txtCiphertext.Text = Elgamal.Encrypt(txtTransCipher.Text)
EncryptTime.Stop()
If EncryptTime.ElapsedMilliseconds < 1000 Then
time = EncryptTime.ElapsedMilliseconds.ToString & " miliseconds"
ElseIf EncryptTime.ElapsedMilliseconds < 60000 Then
time = Math.Round((EncryptTime.ElapsedMilliseconds / 1000), 3).ToString & " seconds"
Else
time = Math.Round((EncryptTime.ElapsedMilliseconds / 60000), 3).ToString & " minutes"
End If
lblTimeEncrypt.Text = "Time to Encrypt File : " & time
End Sub
Private Sub btnGetPrime_Click(ByVal sender As System.Object, ByVal e As System.EventArgs)
Handles btnGetPrime.Click

txtPrime.Text = Elgamal.getPrime(optBit.Value).ToString()
End Sub
Private Sub btnGenerate_Click(ByVal sender As System.Object, ByVal e As System.EventArgs)
Handles btnGenerate.Click
If txtPrime.Text = "" Then
MessageBox.Show("Choose Prime Number First", "Generate Key", MessageBoxButtons.OK,
MessageBoxIcon.Exclamation)
txtPrime.Focus()
Exit Sub
End If
Dim GenerateTime As Stopwatch = New Stopwatch()
GenerateTime.Start()
Elgamal.GenerateKey(BigInteger.Parse(txtPrime.Text))
If Elgamal.isInputPrime = True Then
txtAlpha.Text = alpha
txtA.Text = a
txtAlphaA.Text = alphaA
Else
txtAlpha.Text = ""
txtA.Text = ""

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txtAlphaA.Text = ""
txtPrime.Focus()
End If
GenerateTime.Stop()
Dim time As String = ""
If GenerateTime.ElapsedMilliseconds < 1000 Then
time = GenerateTime.ElapsedMilliseconds.ToString & " miliseconds"
ElseIf GenerateTime.ElapsedMilliseconds < 60000 Then
time = Math.Round((GenerateTime.ElapsedMilliseconds / 1000), 3).ToString & " seconds"
Else
time = Math.Round((GenerateTime.ElapsedMilliseconds / 60000), 3).ToString & " minutes"
End If
lblTimeGenerate.Text = "Time to Generate Key : " & time
End Sub
Private Sub btnOpen_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles
btnOpen.Click

Dim open As OpenFileDialog = New OpenFileDialog()
open.Filter = "txt Files|*.txt"
open.FileName = "*.txt"
If (open.ShowDialog() = DialogResult.OK) Then
Dim fstream As FileStream = New FileStream(open.FileName, FileMode.Open,
FileAccess.ReadWrite)
Dim sreader As StreamReader = New StreamReader(fstream)
sreader.BaseStream.Seek(0, SeekOrigin.Begin)
txtPlaintext.Text = sreader.ReadToEnd()
sreader.Close()
lblFilename.Text = ": " & Path.GetFileName(open.FileName)
lblLocation.Text = ": " & Path.GetFullPath(open.FileName)
End If
End Sub
Private Sub btnSave_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles
btnSave.Click
Dim saveFileDialog1 As SaveFileDialog = New SaveFileDialog
saveFileDialog1.Filter = "txt files |*.txt|All files |*.*"
saveFileDialog1.Title = "Save File"
saveFileDialog1.FileName = "*.txt"

If (saveFileDialog1.ShowDialog() = DialogResult.OK) Then
Dim filename As String = saveFileDialog1.FileName
Dim fstream As FileStream = New FileStream(filename, FileMode.OpenOrCreate)
Dim sw As StreamWriter = New StreamWriter(fstream)
Dim seekorigin As SeekOrigin = New SeekOrigin()
sw.BaseStream.Seek(0, seekorigin)
sw.WriteLine(txtCiphertext.Text)
sw.Flush()
sw.Close()
End If

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End Sub
Private Sub TriGrid_MouseHover(ByVal sender As System.Object, ByVal e As System.EventArgs)
Handles TriGrid.MouseHover
If TriGrid.Dock = DockStyle.None Then
ToolTip1.Show("Double Click to Enlarge", Me.TriGrid, 1000)
Else

ToolTip1.Hide(Me.TriGrid)
End If
End Sub
Private Sub TriGrid_DoubleClick(ByVal sender As System.Object, ByVal e As System.EventArgs)
Handles TriGrid.DoubleClick
If TriGrid.Dock = DockStyle.Fill Then
isLarge = False
UltraGroupBox4.Dock = DockStyle.None
TriGrid.Dock = DockStyle.None
Else
isLarge = True
UltraGroupBox4.Dock = DockStyle.Fill
TriGrid.Dock = DockStyle.Fill
UltraGroupBox4.BringToFront()
TriGrid.BringToFront()
EscSplash.Show()
ToolTip1.Hide(Me.TriGrid)
End If
End Sub
Private Sub TriGrid_KeyDown(ByVal sender As System.Object, ByVal e As

System.Windows.Forms.KeyEventArgs) Handles TriGrid.KeyDown
If e.KeyCode = Keys.Escape Then
isLarge = False
UltraGroupBox4.Dock = DockStyle.None
TriGrid.Dock = DockStyle.None
End If
End Sub
Private Sub TriGrid_MouseLeave(ByVal sender As Object, ByVal e As System.EventArgs) Handles
TriGrid.MouseLeave
isLarge = True
End Sub
Private Sub EncryptControl_Load(ByVal sender As System.Object, ByVal e As System.EventArgs)
Handles MyBase.Load
primeNumber = 0
alpha = 0
a=0
b=0
alphaA = 0
plaintext = 0
ciphertext = 0

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End Sub
Private Sub txtPrime_ValueChanged(ByVal sender As System.Object, ByVal e As System.EventArgs)
Handles txtPrime.ValueChanged
If txtPrime.Text "" Then
primeNumber = txtPrime.Text
End If
End Sub
End Class

3.

Listing Program untuk Form Decrypt

Imports System.Numerics
Imports System.IO
Imports Infragistics.Win.UltraWinGrid
Public Class DecryptControl
Private isLarge As Boolean = False
Private Sub btnDecrypt_Click(ByVal sender As System.Object, ByVal e As System.EventArgs)
Handles btnDecrypt.Click
If (txtCiphertext.Text = "") Then
MessageBox.Show("Input your Ciphertext", "", MessageBoxButtons.OK,
MessageBoxIcon.Warning)
txtCiphertext.Focus()
Exit Sub
End If
If (txtPrime.Text = "") Then
MessageBox.Show("Prime number is missing", "", MessageBoxButtons.OK,
MessageBoxIcon.Warning)
txtPrime.Focus()
Exit Sub
End If
If (txtA.Text = "") Then
MessageBox.Show("Private Key is missing", "", MessageBoxButtons.OK,
MessageBoxIcon.Warning)
txtA.Focus()
Exit Sub
End If
If (Not (Elgamal.Fermat(primeNumber))) Then
MessageBox.Show("Number is not Prime", "", MessageBoxButtons.OK,
MessageBoxIcon.Warning)
txtPrime.Focus()
Exit Sub
End If
Dim EncryptTime As Stopwatch = New Stopwatch()

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Dim time As String = ""
EncryptTime.Start()
txtPlaintext.Text = Elgamal.Decrypt(txtCiphertext.Text)
Dim trans As Transpose = New Transpose
txtTransPlain.Text = trans.TransposeDecrypt(txtPlaintext.Text)
TriGrid.DataSource = trans.getTriangle()
TriGrid.DisplayLayout.Override.DefaultColWidth = 25
TriGrid.DisplayLayout.Override.HeaderClickAction = HeaderClickAction.Select
TriGrid.DisplayLayout.Override.SelectTypeCol = SelectType.None
TriGrid.DisplayLayout.Override.CellClickAction = CellClickAction.RowSelect
EncryptTime.Stop()
If EncryptTime.ElapsedMilliseconds < 1000 Then
time = EncryptTime.ElapsedMilliseconds.ToString & " miliseconds"
ElseIf EncryptTime.ElapsedMilliseconds < 60000 Then
time = Math.Round((EncryptTime.ElapsedMilliseconds / 1000), 3).ToString & " seconds"
Else
time = Math.Round((EncryptTime.ElapsedMilliseconds / 60000), 3).ToString & " minutes"
End If
lblTimeDecrypt.Text = "Time to Decrypt File : " & time
End Sub
Private Sub txtPrime_ValueChanged(ByVal sender As System.Object, ByVal e As System.EventArgs)
Handles txtPrime.ValueChanged
If (txtPrime.Text "") Then
primeNumber = BigInteger.Parse(txtPrime.Text)
End If
End Sub
Private Sub txtA_ValueChanged(ByVal sender As System.Object, ByVal e As System.EventArgs)
Handles txtA.ValueChanged
If txtA.Text "" Then
a = BigInteger.Parse(txtA.Text)
End If
End Sub
Private Sub btnSave_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles
btnSave.Click
Dim saveFileDialog1 As SaveFileDialog = New SaveFileDialog
saveFileDialog1.Filter = "txt files |*.txt|All files |*.*"
saveFileDialog1.Title = "Save File"
saveFileDialog1.FileName = "*.txt"
If (saveFileDialog1.ShowDialog() = DialogResult.OK) Then
Dim filename As String = saveFileDialog1.FileName
Dim fstream As FileStream = New FileStream(filename, FileMode.OpenOrCreate)
Dim sw As StreamWriter = New StreamWriter(fstream)
Dim seekorigin As SeekOrigin = New SeekOrigin()

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sw.BaseStream.Seek(0, seekorigin)
sw.WriteLine(txtTransPlain.Text)
sw.Flush()
sw.Close()
End If
End Sub
Private Sub btnOpen_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles
btnOpen.Click
Dim open As OpenFileDialog = New OpenFileDialog()
open.Filter = "txt Files|*.txt"
open.FileName = "*.txt"
If (open.ShowDialog() = DialogResult.OK) Then
Dim fstream As FileStream = New FileStream(open.FileName, FileMode.Open,
FileAccess.ReadWrite)
Dim sreader As StreamReader = New StreamReader(fstream)
sreader.BaseStream.Seek(0, SeekOrigin.Begin)
txtCiphertext.Text = sreader.ReadToEnd()
sreader.Close()
lblFilename.Text = ": " & Path.GetFileName(open.FileName)
lblLocation.Text = ": " & Path.GetFullPath(open.FileName)
End If
End Sub
Private Sub txtCiphertext_ValueChanged(ByVal sender As System.Object, ByVal e As
System.EventArgs) Handles txtCiphertext.ValueChanged
lblChar.Text = ": " & txtCiphertext.Text.Split(" ").Length - 1 & " Char"
End Sub
Private Sub TriGrid_MouseHover(ByVal sender As System.Object, ByVal e As System.EventArgs)
Handles TriGrid.MouseHover
If TriGrid.Dock = DockStyle.None Then
ToolTip1.Show("Double Click to Enlarge", Me.TriGrid, 1000)
Else
ToolTip1.Hide(Me.TriGrid)
End If
End Sub
Private Sub TriGrid_DoubleClick(ByVal sender As System.Object, ByVal e As System.EventArgs)
Handles TriGrid.DoubleClick
If TriGrid.Dock = DockStyle.Fill Then
isLarge = False
UltraGroupBox4.Dock = DockStyle.None
TriGrid.Dock = DockStyle.None
Else
isLarge = True
UltraGroupBox4.Dock = DockStyle.Fill
TriGrid.Dock = DockStyle.Fill
UltraGroupBox4.BringToFront()
TriGrid.BringToFront()
EscSplash.Show()

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ToolTip1.Hide(Me.TriGrid)
End If
End Sub
Private Sub TriGrid_KeyDown(ByVal sender As System.Object, ByVal e As
System.Windows.Forms.KeyEventArgs) Handles TriGrid.KeyDown
If e.KeyCode = Keys.Escape Then
isLarge = False
UltraGroupBox4.Dock = DockStyle.None
TriGrid.Dock = DockStyle.None
End If
End Sub
Private Sub DecryptControl_MouseLeave(ByVal sender As Object, ByVal e As System.EventArgs)
Handles Me.MouseLeave
isLarge = True
End Sub
Private Sub DecryptControl_Load(ByVal sender As System.Object, ByVal e As System.EventArgs)
Handles MyBase.Load
alpha = 0
b=0
alphaA = 0
plaintext = 0
ciphertext = 0
txtPrime.Text = primeNumber.ToString()
txtA.Text = a.ToString()
End Sub
End Class

4. Listing Program untuk Class ElGamal
Imports System.Numerics
Imports System.IO
Public Class Elgamal
Public Shared isInputPrime As Boolean
Private Shared primitiveRoots As New ArrayList
Dim r As BigInteger()
Private Shared Rnd As Random = New Random()
Private Shared primitiveRootsTotal As Integer
Private Shared KeyLimit As Integer
Public Shared Function Fermat(ByVal prime As BigInteger) As Boolean
Dim a As BigInteger = 0
For i = 0 To prime.ToString().Length
a = Random(prime)
If (Not (BigInteger.ModPow(a, prime - 1, prime).IsOne)) Then
Return False

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End If
Next
Return True
End Function
Public Shared Function Random(ByVal prime As BigInteger) As BigInteger
Dim bigVal As BigInteger
Dim limit As Integer = Rnd.Next(2, prime.ToString().Length)
Do
Dim strVal As String = ""
If (prime.ToString().Length = 1) Then
For i = 0 To prime.ToString().Length - 1
Dim val = Rnd.Next(2, 10)
strVal += val.ToString()
Next
bigVal = BigInteger.Parse(strVal)
Else
Dim val As Integer
For i = 0 To limit - 1
If (i = 0) Then
val = Rnd.Next(0, Convert.ToInt32(prime.ToString().Substring(0, 1)))
strVal += val.ToString()
Else
val = Rnd.Next(0, 10)
strVal += val.ToString()
End If
Next
bigVal = BigInteger.Parse(strVal)
End If
Loop While (bigVal < 2 Or bigVal >= prime)
Return bigVal
End Function
Public Shared Function orderNumber(ByVal prime As Integer, ByVal n As Integer) As BigInteger
Dim hasil As BigInteger = 0
Dim i As Integer = 1
While hasil 1
hasil = BigInteger.ModPow(n, i, prime)
i += 1
End While
Return i - 1
End Function
Public Shared Function getTotien(ByVal value As Integer) As Integer
Dim retValue As Integer = 0
For i = 1 To value
If (BigInteger.GreatestCommonDivisor(i, value).IsOne) Then
retValue += 1
End If
Next

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Return retValue
End Function
Public Shared Function getPrimitiveRoot(ByVal prime As BigInteger) As Integer
Dim totienP As Integer = prime - 1
Dim leastPrimitive As Integer = 0
Dim hasil As BigInteger = 0
Dim powers As Integer = 2
Dim factor As List(Of Long) = FindFactors(prime - 1)
Dim nilaiRandom As Integer
leastPrimitive = powerTest(factor)
primitiveRoots.Add(leastPrimitive)
If prime < 9999 Then
For i = leastPrimitive To prime - 1
If (BigInteger.GreatestCommonDivisor(i, prime - 1).IsOne) Then
primitiveRoots.Add(i)
End If
Next
Dim ordNum As BigInteger
Do
nilaiRandom = Rnd.Next(0, primitiveRoots.Count - 1)
ordNum = orderNumber(prime, Integer.Parse(primitiveRoots(nilaiRandom).ToString()))
If totienP = ordNum Then
hasil = BigInteger.Parse(primitiveRoots(nilaiRandom).ToString())
End If
Loop While totienP ordNum
Else
While prime > hasil
If (BigInteger.GreatestCommonDivisor(powers, prime - 1).IsOne) Then
hasil = Math.Pow(leastPrimitive, powers)
primitiveRoots.Add(hasil)
End If
powers += 1
End While
primitiveRoots.RemoveAt(primitiveRoots.Count - 1)
nilaiRandom = Rnd.Next(0, primitiveRoots.Count - 1)
If (BigInteger.ModPow(BigInteger.Parse(primitiveRoots(nilaiRandom).ToString()),
BigInteger.Parse(totienP.ToString()), prime).IsOne) Then
hasil = BigInteger.Parse(primitiveRoots(nilaiRandom).ToString())
End If
End If
Return hasil
End Function
Public Shared Function getPrime(ByVal bit As Integer) As BigInteger

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Dim isPrime As Boolean = False
Dim prime As BigInteger = 0
While (Not isPrime)
Dim value As BigInteger = Rnd.Next(100, bit)
If (Fermat(value)) Then
isPrime = True
prime = value.ToString()
End If
End While
Return prime
End Function
Public Shared Sub GenerateKey(ByVal prime As BigInteger)
primitiveRoots.Clear()
primeNumber = prime
If primeNumber > 9999 Then
KeyLimit = 9999
Else
KeyLimit = primeNumber
End If
If (Fermat(primeNumber)) Then
alpha = getPrimitiveRoot(primeNumber)
a = Rnd.Next(2, KeyLimit - 1)
alphaA = BigInteger.ModPow(alpha, a, primeNumber)
isInputPrime = True
Else
MessageBox.Show("The Number is not Prime", "Generate Key", MessageBoxButtons.OK,
MessageBoxIcon.Warning)
isInputPrime = False
End If
End Sub
Public Shared Function Encrypt(ByVal plain As String) As String
Dim cipher1 As BigInteger()
Dim cipher2 As BigInteger()
Dim m As Integer
plaintext = plain
Dim idx As Integer = 0
cipher1 = New BigInteger(plaintext.Length) {}
cipher2 = New BigInteger(plaintext.Length) {}
Dim rnd As New Random
For Each c In plaintext
m = System.Convert.ToInt32(c)
b = rnd.Next(2, KeyLimit - 1)
cipher1(idx) = BigInteger.ModPow(alpha, b, primeNumber)
cipher2(idx) = (m * (BigInteger.Pow(alphaA, b))) Mod primeNumber
idx += 1
Next
For i = 0 To cipher1.Length - 2

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ciphertext &= cipher1(i).ToString() & " "
Next
ciphertext += "/"
For i = 0 To cipher2.Length - 2
ciphertext &= cipher2(i).ToString() & " "
Next
Return ciphertext
End Function
Public Shared Function Decrypt(ByVal cipher As String) As String
Dim cipher1 As BigInteger()
Dim cipher2 As BigInteger()
Dim ciphertext = cipher.Split("/")
Dim m1, m2 As BigInteger
Dim plaintext As String = ""
Dim cip1 = ciphertext(0).Split(" ")
cipher1 = New BigInteger(cip1.Length - 2) {}
For i = 0 To cip1.Length - 2
cipher1(i) = cip1(i)
Next
Dim cip2 = ciphertext(1).Split(" ")
cipher2 = New BigInteger(cip2.Length - 2) {}
For i = 0 To cip2.Length - 2
cipher2(i) = cip2(i)
Next
For i = 0 To cipher1.Length - 1
m1 = BigInteger.ModPow(cipher1(i), (primeNumber - 1 - a), primeNumber)
m2 = (m1 * cipher2(i)) Mod primeNumber
plaintext &= Char.ConvertFromUtf32(m2)
Next
Return plaintext
End Function
Public Shared Function FindFactors(ByVal num As Long) As List(Of Long)
Dim result As List(Of Long) = New List(Of Long)()
Do While (num Mod 2 = 0)
result.Add(2)
num \= 2
Loop
Dim factor As Long = 3
Do While (factor * factor 1) Then result.Add(num)
Dim flag As Integer = 0
For i = 1 To result.Count - 1
If (result(flag) = result(i)) Then
result(i) = 0
Else
flag = i
End If
Next
For i = 1 To result.Count - 1
result.Remove(0)
Next
Return result
End Function
Public Shared Function powerTest(ByVal factors As List(Of Long)) As Integer
Dim hasil As Integer = 1
Dim value As Integer = 2
Dim powertes As List(Of Long) = New List(Of Long)()
For i = 0 To factors.Count - 1
powertes.Add(((primeNumber - 1) / factors(i)))
Next
While hasil = 1
For i = 0 To powertes.Count - 1
hasil = BigInteger.ModPow(value, powertes(i), primeNumber)
If hasil = 1 Then
Exit For
End If
Next
value += 1
End While
Return value - 1
End Function
End Class

5. Listing Program untuk Class Transpose
Public Class Transpose
#Region "Variable"

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Public ciphertext As String = ""
Public plaintext As String = ""
Dim pola As String = ""
Dim textLength As Integer = 0
Dim j As Integer = 1
Dim limit As Integer = 1
Dim row As Integer = 1
Dim col As Integer = 0
Dim triangle As String(,)
#End Region
Public Function TransposeEncrypt(ByVal plain As String) As String
plaintext = plain
textLength = plain.Length
limit = 1
row = 1
j=1
For i = 1 To textLength
If textLength > limit Then
j += 2
limit += j
row += 1
End If
Next
j=1
col = 0
For i = 1 To row
col += j
j=2
Next
row -= 1
col -= 1
triangle = New String(row, col) {}
Dim mid As Integer = Math.Floor((col + 1) / 2)
Dim idx As Integer = 0
For i = 0 To row
For j = (mid - i) To (mid + i)
If (textLength limit Then
j += 2
limit += j
row += 1
End If
Next
j=1
col = 0
For i = 1 To row
col += j
j=2
Next
row -= 1
col -= 1
triangle = New String(row, col) {}
Dim mid As Integer = col / 2
Dim idx As Integer = 0
For i = 0 To col
If i > mid Then
For j = i - row To row
triangle(j, i) = ciphertext(idx)
idx += 1
Next
Else
For j = (row - i) To row
triangle(j, i) = ciphertext(idx)
idx += 1
Next
End If

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Next
For i = 0 To row
For j = 0 To col
If (triangle(i, j) "") Then
plain += triangle(i, j)
End If
Next
Next
plaintext = plain.Trim(Chr(191))
Return plaintext
End Function
Public Function getTriangle() As DataTable
Dim dt As DataTable = New DataTable()
For i = 0 To col
dt.Columns.Add(New DataColumn(i + 1))
Next
For i = 0 To row
dt.Rows.Add()
Next
For i = 0 To row
For j = 0 To col
dt.Rows(i)(j) = triangle(i, j)
Next
Next
Return dt
End Function
End Class

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CURRICULUM VITAE

Nama

: Ismail Fata Lubis

Tempat/Tanggal Lahir : Sibolga, 5 Oktober 1990
Agama

: Islam

Alamat Sekarang

: Jl. Jalak 12 No. 195 P. Mandala Medan

Alamat Orang Tua

: Jl. Jalak 12 No. 195 P. Mandala Medan

Telp/ Hp

: 081375530101

Email

: ismailfatalubis@yahoo.co.id

Riwayat Pendidikan
2009 – 2015

: S1 Ilmu Komputer Universitas Sumatera Utara, Medan

2005 – 2008

: SMA Negeri 8 Medan

2002 – 2005

: SMP Negeri 13 Medan

1996 – 2002

: SDN 067980 Medan

Pengalaman Organisasi dan Kegiatan Ilmiah

 Anggota Departemen Komunikasi dan Informasi Pemerintahan Mahasiswa Fakultas
Matematika dan Ilmu Pengetahuan Alam (PEMA FMIPA) periode 2010-2011

 Anggota Departemen Seni & Olahraga Ikatan Mahasiswa S1 Ilmu Komputer
(IMILKOM) periode 2011-2012

 Anggota Departemen Sumber Daya Mahasiswa Pemerintahan Mahasiswa Fakultas
Ilmu Komputer dan Teknologi Informasi (PEMA FASILKOM-TI) periode 20122013

 Anggota bidang Programming kepanitiaan ARTechno 2013

 Ketua bidang Humas kepanitiaan Penerimaan Mahasiswa Baru (PMB) Ilmu
Komputer USU Tahun 2011

Universitas Sumatera Utara