ToolTip1.HideMe.TriGrid End If
End Sub Private Sub TriGrid_KeyDownByVal 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_MouseLeaveByVal sender As Object, ByVal e As System.EventArgs
Handles Me.MouseLeave isLarge = True
End Sub Private Sub DecryptControl_LoadByVal 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 FermatByVal prime As BigInteger As Boolean
Dim a As BigInteger = 0 For i = 0 To prime.ToString.Length
a = Randomprime If Not BigInteger.ModPowa, prime - 1, prime.IsOne Then
Return False
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End If Next
Return True End Function
Public Shared Function RandomByVal prime As BigInteger As BigInteger Dim bigVal As BigInteger
Dim limit As Integer = Rnd.Next2, 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.Next2, 10
strVal += val.ToString Next
bigVal = BigInteger.ParsestrVal Else
Dim val As Integer For i = 0 To limit - 1
If i = 0 Then val = Rnd.Next0, Convert.ToInt32prime.ToString.Substring0, 1
strVal += val.ToString Else
val = Rnd.Next0, 10 strVal += val.ToString
End If Next
bigVal = BigInteger.ParsestrVal End If
Loop While bigVal 2 Or bigVal = prime Return bigVal
End Function Public Shared Function orderNumberByVal prime As Integer, ByVal n As Integer As BigInteger
Dim hasil As BigInteger = 0 Dim i As Integer = 1
While hasil 1 hasil = BigInteger.ModPown, i, prime
i += 1 End While
Return i - 1 End Function
Public Shared Function getTotienByVal value As Integer As Integer Dim retValue As Integer = 0
For i = 1 To value If BigInteger.GreatestCommonDivisori, value.IsOne Then
retValue += 1 End If
Next
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Return retValue End Function
Public Shared Function getPrimitiveRootByVal 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 ListOf Long = FindFactorsprime - 1
Dim nilaiRandom As Integer leastPrimitive = powerTestfactor
primitiveRoots.AddleastPrimitive If prime 9999 Then
For i = leastPrimitive To prime - 1 If BigInteger.GreatestCommonDivisori, prime - 1.IsOne Then
primitiveRoots.Addi End If
Next Dim ordNum As BigInteger
Do nilaiRandom = Rnd.Next0, primitiveRoots.Count - 1
ordNum = orderNumberprime, Integer.ParseprimitiveRootsnilaiRandom.ToString If totienP = ordNum Then
hasil = BigInteger.ParseprimitiveRootsnilaiRandom.ToString End If
Loop While totienP ordNum Else
While prime hasil If BigInteger.GreatestCommonDivisorpowers, prime - 1.IsOne Then
hasil = Math.PowleastPrimitive, powers primitiveRoots.Addhasil
End If powers += 1
End While primitiveRoots.RemoveAtprimitiveRoots.Count - 1
nilaiRandom = Rnd.Next0, primitiveRoots.Count - 1 If BigInteger.ModPowBigInteger.ParseprimitiveRootsnilaiRandom.ToString,
BigInteger.ParsetotienP.ToString, prime.IsOne Then hasil = BigInteger.ParseprimitiveRootsnilaiRandom.ToString
End If End If
Return hasil End Function
Public Shared Function getPrimeByVal 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.Next100, bit
If Fermatvalue Then isPrime = True
prime = value.ToString End If
End While Return prime
End Function Public Shared Sub GenerateKeyByVal prime As BigInteger
primitiveRoots.Clear primeNumber = prime
If primeNumber 9999 Then KeyLimit = 9999
Else KeyLimit = primeNumber
End If If FermatprimeNumber Then
alpha = getPrimitiveRootprimeNumber a = Rnd.Next2, KeyLimit - 1
alphaA = BigInteger.ModPowalpha, a, primeNumber isInputPrime = True
Else MessageBox.ShowThe Number is not Prime, Generate Key, MessageBoxButtons.OK,
MessageBoxIcon.Warning isInputPrime = False
End If End Sub
Public Shared Function EncryptByVal 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 BigIntegerplaintext.Length {} cipher2 = New BigIntegerplaintext.Length {}
Dim rnd As New Random For Each c In plaintext
m = System.Convert.ToInt32c b = rnd.Next2, KeyLimit - 1
cipher1idx = BigInteger.ModPowalpha, b, primeNumber cipher2idx = m BigInteger.PowalphaA, b Mod primeNumber
idx += 1 Next
For i = 0 To cipher1.Length - 2
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ciphertext = cipher1i.ToString Next
ciphertext += For i = 0 To cipher2.Length - 2
ciphertext = cipher2i.ToString Next
Return ciphertext End Function
Public Shared Function DecryptByVal 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 = ciphertext0.Split cipher1 = New BigIntegercip1.Length - 2 {}
For i = 0 To cip1.Length - 2 cipher1i = cip1i
Next Dim cip2 = ciphertext1.Split
cipher2 = New BigIntegercip2.Length - 2 {} For i = 0 To cip2.Length - 2
cipher2i = cip2i Next
For i = 0 To cipher1.Length - 1 m1 = BigInteger.ModPowcipher1i, primeNumber - 1 - a, primeNumber
m2 = m1 cipher2i Mod primeNumber plaintext = Char.ConvertFromUtf32m2
Next Return plaintext
End Function Public Shared Function FindFactorsByVal num As Long As ListOf Long
Dim result As ListOf Long = New ListOf Long Do While num Mod 2 = 0
result.Add2 num \= 2
Loop Dim factor As Long = 3
Do While factor factor = num If num Mod factor = 0 Then
result.Addfactor num \= factor
Else factor += 2
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End If Loop
If num 1 Then result.Addnum Dim flag As Integer = 0
For i = 1 To result.Count - 1 If resultflag = resulti Then
resulti = 0 Else
flag = i End If
Next For i = 1 To result.Count - 1
result.Remove0 Next
Return result End Function
Public Shared Function powerTestByVal factors As ListOf Long As Integer Dim hasil As Integer = 1
Dim value As Integer = 2 Dim powertes As ListOf Long = New ListOf Long
For i = 0 To factors.Count - 1 powertes.AddprimeNumber - 1 factorsi
Next While hasil = 1
For i = 0 To powertes.Count - 1 hasil = BigInteger.ModPowvalue, powertesi, 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
