public sub main()
dim key as string
for i = 1 to 16
randomize
key = key & chr(rnd * 255)
next i
msgbox rc4(rc4("welcome to plindge studio!", key), key)
end sub
public function rc4(inp as string, key as string) as string
dim s(0 to 255) as byte, k(0 to 255) as byte, i as long
dim j as long, temp as byte, y as byte, t as long, x as long
dim outp as string
for i = 0 to 255
s(i) = i
next
j = 1
for i = 0 to 255
if j > len(key) then j = 1
k(i) = asc(mid(key, j, 1))
j = j + 1
next i
j = 0
for i = 0 to 255
j = (j + s(i) + k(i)) mod 256
temp = s(i)
s(i) = s(j)
s(j) = temp
next i
i = 0
j = 0
for x = 1 to len(inp)
i = (i + 1) mod 256
j = (j + s(i)) mod 256
temp = s(i)
s(i) = s(j)
s(j) = temp
t = (s(i) + (s(j) mod 256)) mod 256
y = s(t)
outp = outp & chr(asc(mid(inp, x, 1)) xor y)
next
rc4 = outp
end function
一个简单实用的 vb 加密/解密算法
Function UserCode(password As String) As String
'用户口令加密
Dim il_bit, il_x, il_y, il_z, il_len, i As Long
Dim is_out As String
il_len = Len(password)
il_x = 0
il_y = 0
is_out = ""
For i = 1 To il_len
il_bit = AscW(Mid(password, i, 1)) 'W系列支持unicode
password = is_out
il_len = Len(password)
il_x = 0
il_y = 0
is_out = ""
For i = 1 To il_len
il_bit = AscW(Mid(password, i, 1))
'取前4位值
il_y = il_bit / 16 + 64
is_out = is_out & ChrW(Fix(il_y))
'取后4位值
il_y = (il_bit Mod 16) + 64
is_out = is_out & ChrW(Fix(il_y))
Next
UserCode = is_out
End Function
Function UserDeCode(password As String) As String
'口令解密
Dim is_out As String
Dim il_x, il_y, il_len, i, il_bit As Long
il_len = Len(password)
il_x = 0
il_y = 0
is_out = ""
For i = 1 To il_len Step 2
il_bit = AscW(Mid(password, i, 1))
'取前4位值
il_y = (il_bit - 64) * 16
'取后4位值
'dd = AscW(Mid(password, i + 1, 1)) - 64
il_y = il_y + AscW(Mid(password, i + 1, 1)) - 64
is_out = is_out & ChrW(il_y)
Next
For i = (il_len - 1) To 1 Step -1
il_y = il_x * 256 + AscW(Mid(password, i, 1))
il_x = il_y Mod 13
is_out = ChrW(Fix(il_y / 13)) & is_out
Next
UserDeCode = is_out
End Function