Beberapa Contoh Program Kriptografi
Pengertian Kriptografi - Secara etimologi (ilmu asal usul kata),
kata kriptografi berasal dari gabungan dua kata dalam bahasa Yunani
yaitu “kriptos” dan “graphia”. Kata kriptos digunakan untuk
mendeskripsikan sesuatu yang disembunyikan, rahasia atau misterius.
Sedangkan kata graphia berarti tulisan. Kriptografi didefinisikan
sebagai ilmu dan pelajaran untuk tulisan rahasia dengan pertimbangan
bahwa komunikasi dan data dapat dikodekan untuk mencegah dari mata-mata
atau orang lain yang ingin mengetahui isinya, dengan menggunakan
kode-kode dan aturan-aturan tertentu dan metode lainnya sehingga hanya
orang yang berhak yang dapat mengetahui isi pesan sebenarnya.
1.Caesar Chiper
Dibawah
ini Listing programnya Untuk form menu :
Public Class Form1
Private Sub CaesarChiperToolStripMenuItem_Click(ByVal sender As
System.Object, ByVal e As
System.EventArgs) Handles
CaesarChiperToolStripMenuItem.Click
Caesar_Chiper.Show()
Me.Hide()
End Sub
Private Sub VigenereChiperToolStripMenuItem_Click(ByVal sender As
System.Object, ByVal e As
System.EventArgs) Handles
VigenereChiperToolStripMenuItem.Click
Vigenera.Show()
Me.Hide()
End Sub
Private Sub VernamChiperToolStripMenuItem_Click(ByVal sender As
System.Object, ByVal e As
System.EventArgs) Handles
VernamChiperToolStripMenuItem.Click
Vernam.Show()
Me.Hide()
End Sub
Private Sub DesChiperToolStripMenuItem_Click(ByVal sender As
System.Object, ByVal e As
System.EventArgs) Handles
DesChiperToolStripMenuItem.Click
Des_Chiper.Show()
Me.Hide()
End Sub
Private Sub RC4ToolStripMenuItem_Click(ByVal sender As
System.Object, ByVal e As
System.EventArgs) Handles
RC4ToolStripMenuItem.Click
End Sub
Private Sub KeluarToolStripMenuItem_Click(ByVal sender As
System.Object, ByVal e As
System.EventArgs) Handles
KeluarToolStripMenuItem.Click
Me.Close()
End Sub
End Class
Dan
ini untuk listing program caesar chiper :
Public Class Caesar_Chiper
Private Sub Btn_Enkrip_Click(ByVal
sender As System.Object, ByVal e As
System.EventArgs) Handles Btn_Enkrip.Click
Dim
jumlah As Double
= Len(Chiperteks.Text)
Dim x As String
Dim
xkalimat As String
= ""
Dim i As Double
Dim bil
As Integer
For i =
1 To jumlah
x = Mid(Chiperteks.Text, i, 1)
bil = Asc(x) + 1
x = Chr(bil)
xkalimat = xkalimat + x
Next i
Plainteks.Text = xkalimat
End Sub
Private Sub Btn_Hapus_Click(ByVal
sender As System.Object, ByVal e As
System.EventArgs) Handles Btn_Hapus.Click
Plainteks.Text = ""
Chiperteks.Text = ""
End Sub
Private Sub Btn_keluar_Click(ByVal
sender As System.Object, ByVal e As
System.EventArgs) Handles Btn_keluar.Click
End
End Sub
Private Sub Caesar_Chiper_Load(ByVal
sender As System.Object, ByVal e As
System.EventArgs) Handles MyBase.Load
Plainteks.Text = ""
Chiperteks.Text = ""
End Sub
End Class
2. Gronsfeld Chiper
3.Vernam Chiper
Dibawah ini Listing
programnya :
Public Class Vernam
Private Sub Plainteks_KeyPress(ByVal
sender As Object,
ByVal e As
System.Windows.Forms.KeyPressEventArgs) Handles
Plainteks.KeyPress
e.KeyChar = UCase(e.KeyChar)
Dim
tombol As Integer
= Asc(e.KeyChar)
If Not (((tombol >= 65) And
(tombol <= 90)) Or (tombol = 8)) Then
e.Handled = True
End If
End Sub
Private Sub Btn_Enkrip_Click(ByVal
sender As System.Object, ByVal e As
System.EventArgs) Handles Btn_Enkrip.Click
Dim j As Integer
Dim jum
As Integer
Dim
sKey As String
Dim
nKata As Integer
Dim
nKunci As Integer
Dim
sKata As String
Dim
sPlain As String
= ""
Dim
nEnc As Integer
j = 0
sKata = Plainteks.Text
jum = Len(sKata)
sKey = Kunci.Text
For i =
1 To jum
If
j = Len(sKey) Then
j = 1
Else
j = j + 1
End
If
nKata = Asc(Mid(sKata, i, 1)) - 65
nKunci = Asc(Mid(sKey, j, 1)) - 65
nEnc = ((nKata + nKunci) Mod 26)
sPlain = sPlain & Chr((nEnc) +
65)
Next i
Chiperteks.Text = sPlain
End Sub
Private Sub Btn_kunci_KeyPress(ByVal
sender As Object,
ByVal e As
System.Windows.Forms.KeyPressEventArgs) Handles
Btn_kunci.KeyPress
e.KeyChar = UCase(e.KeyChar)
Dim
tombol As Integer
= Asc(e.KeyChar)
If Not (((tombol >= 65) And
(tombol <= 90)) Or (tombol = 8)) Then
e.Handled = True
End If
End Sub
Private Sub Vernam_Load(ByVal
sender As System.Object, ByVal e As
System.EventArgs) Handles MyBase.Load
Plainteks.Text = ""
Kunci.Text = ""
Chiperteks.Text = ""
End Sub
Private Sub Btn_Hapus_Click(ByVal
sender As System.Object, ByVal e As
System.EventArgs) Handles Btn_Hapus.Click
Plainteks.Text = ""
Kunci.Text = ""
Chiperteks.Text = ""
End Sub
Private Sub Btn_keluar_Click(ByVal
sender As System.Object, ByVal e As
System.EventArgs) Handles Btn_keluar.Click
End
End Sub
End Class
4.Vegenere Chiper
Listing
programnya :
Public Class Vigenera
Private Sub Btn_Proses_Click(ByVal
sender As System.Object, ByVal e As
System.EventArgs) Handles Btn_Proses.Click
Dim j As Integer
Dim jum
As Integer
Dim
sKey As String
Dim
nKata As Integer
Dim
nKunci As Integer
Dim
sKata As String
Dim
sPlain As String
= ""
Dim
nEnc As Integer
j = 0
sKata = Plainteks.Text
jum = Len(sKata)
sKey = Kunci.Text
For i =
1 To jum
If
j = Len(sKey) Then
j = 1
Else
j = j + 1
End
If
nKata = Asc(Mid(sKata, i, 1)) - 65
nKunci = Asc(Mid(sKey, j, 1)) - 65
nEnc = ((nKata + nKunci) Mod 26)
sPlain = sPlain & Chr((nEnc) +
65)
Next i
Chiperteks.Text = sPlain
End Sub
Private Sub Btn_Hapus_Click(ByVal
sender As System.Object, ByVal e As
System.EventArgs) Handles Btn_Hapus.Click
Plainteks.Text = ""
Kunci.Text = ""
Chiperteks.Text = ""
End Sub
Private Sub Btn_keluar_Click(ByVal
sender As System.Object, ByVal e As
System.EventArgs) Handles Btn_keluar.Click
End
End Sub
Private Sub Btn_kunci_KeyPress(ByVal
sender As Object,
ByVal e As
System.Windows.Forms.KeyPressEventArgs) Handles
Btn_kunci.KeyPress
e.KeyChar = UCase(e.KeyChar)
Dim
tombol As Integer
= Asc(e.KeyChar)
If Not (((tombol >= 65) And
(tombol <= 90)) Or (tombol = 8)) Then
e.Handled = True
End If
End Sub
End Class
5.Des Chiper
Listing
programnya :
Public Class Des_Chiper
Private Sub Btn_Hapus_Click(ByVal
sender As System.Object, ByVal e As
System.EventArgs) Handles Btn_Hapus.Click
Plainteks.Text = ""
Chiperteks.Text = ""
End Sub
Private Sub Btn_keluar_Click(ByVal
sender As System.Object, ByVal e As
System.EventArgs) Handles Btn_keluar.Click
End
End Sub
Private Sub Btn_Deskrip_Click(ByVal
sender As System.Object, ByVal e As
System.EventArgs) Handles Btn_Deskrip.Click
Dim x As String = ""
Dim
xkalimat As String
= ""
For i =
1 To Len(Chiperteks.Text)
x = Mid(Chiperteks.Text, i, i)
x = Chr(Asc(x) - 3)
xkalimat = xkalimat + x
Next
Plainteks.Text = xkalimat
End Sub
End Class
