<%
'------------------
'圖片驗證碼
'netdust
'05-8-29 發布
'以前的圖片驗證碼很容易被破解,所以在其基礎上進行改進,即使知道原始碼
'也很難破解。
'幹擾次數每加一 -> 窮舉法的代價提高約100*100倍
'適當設定雜點幾率可以有效降低軟體識別正確率
'05-12-20 修正了一個錯誤
'------------------
Option Explicit
Call Com_CreatValidCode("GetCode")
Rem 產生驗證碼圖片
Sub Com_CreatValidCode(pSN)
Const codeLen = 4 '驗證碼位元
Const cOdds = 3 '雜點出現的機率
Const dbtTimes = 1 '幹擾次數(安全考慮,最好不要小於3)
Const cAmount = 10 '字型檔數量
Const cCode = "0123456789" '字型檔對應的字元
Const UnitWidth = 16 '字寬(要為4的倍數)
Const UnitHeight = 13 '字高
Const DotsLimit = 5 '每次刪除有效點的上限(避免無法人為識別)
Const tryCount = 5 '避免刪除有效點超過上限的嘗試次數限制
'-----------
Randomize
Dim i, ii, iii
' 禁止緩衝
Response.Expires = -9999
Response.AddHeader "Pragma","no-cache"
Response.AddHeader "cache-ctrol","no-cache"
Response.ContentType = "Image/BMP"
' 顏色的數?字元,背景)
Dim vColorData(1)
vColorData(0) = ChrB(0) & ChrB(0) & ChrB(0) ' 藍0,綠0,紅0(黑色)
vColorData(1) = ChrB(255) & ChrB(255) & ChrB(255) ' 藍250,綠236,紅211(淺藍色)
' 字元的資料(可以自己修改,如果修改了尺寸,記得把前面的設定也改了)
Dim vNumberData(9)
vNumberData(0) = "1111000000001111111000000000011111100111111001111110011111100111111001111110011111100111111001111110011111100111111001111110011111100111111001111110011111100111111001111110011111100000000001111111000000001111"
vNumberData(1) = "1111110001111111111100000111111111100000011111111100110001111111111111000111111111111100011111111111110001111111111111000111111111111100011111111111110001111111111111000111111111100000000011111110000000001111"
vNumberData(2) = "1111110000011111111110000000111111110001110011111110001111001111111111111001111111111111001111111111111001111111111111001111111111111001111111111111001111001111111001111100111111100000000011111110000000001111"
vNumberData(3) = "1111100000011111111100000000111111100111111001111110011111001111111111111001111111111110001111111111111000111111111111111001111111111111110011111110011111100111111001111110011111110000000011111111100000011111"
vNumberData(4) = "1111111100111111111110110011111111110011001111111111001100111111111001110011111111001111001111111000000000000011100000000000001111111111001111111111111100111111111111110011111111111111001111111111111100111111"
vNumberData(5) = "1110000000000111110011111111111111001111111111111100111111111111110011111111111111001100000011111100000111100111111111111110011111111111111001111111111111100111110011111110011111001111111001111110000000001111"
vNumberData(6) = "1111110000011111111110000000111111110011111001111110011111111111111001111111111111100100000111111110000000001111111000111110011111100111111001111110011111100111111001111110011111110000000011111111100000011111"
vNumberData(7) = "1110000000000111111000000000011111100111111001111110011111100111111111111100111111111111110011111111111110011111111111110011111111111111001111111111111100111111111111110011111111111111001111111111111100111111"
vNumberData(8) = "1111100000011111111100000000111111100111111001111110011111100111111001111110011111110000000011111111000000001111111100111100111111100111111001111110011111100111111001111110011111110000000011111111100000011111"
vNumberData(9) = "1111100000011111111100000000111111100111111001111110011111100111111001111110011111110000000001111111000000100111111111111110011111111111111001111111111111100111111001111100111111110000000011111111100000011111"
' 隨機產生字元
Dim vCodes
ReDim vCode(codeLen-1)
For i = 0 To codeLen-1
vCode(i) = Int(Rnd * cAmount)
vCodes = vCodes & Mid(cCode, vCode(i) + 1, 1)
vCode(i) = pcd_doubter(vNumberData(vCode(i)),UnitWidth,UnitHeight,DotsLimit,tryCount,dbtTimes)
Next
Session(pSN) = vCodes '記錄入Session
' 輸出影像檔頭
Response.BinaryWrite ChrB(66) & ChrB(77) & Num2ChrB(54+UnitWidth*UnitHeight*CodeLen*3,4) & ChrB(0) & ChrB(0) &_
ChrB(0) & ChrB(0) & ChrB(54) & ChrB(0) & ChrB(0) & ChrB(0) & ChrB(40) & ChrB(0) &_
ChrB(0) & ChrB(0) & Num2ChrB(UnitWidth*CodeLen,4) & Num2ChrB(UnitHeight,4) &_
ChrB(1) & ChrB(0)
' 輸出映像資訊頭
Response.BinaryWrite ChrB(24) & ChrB(0) & ChrB(0) & ChrB(0) & ChrB(0) & ChrB(0) & Num2ChrB(UnitWidth*UnitHeight*CodeLen*3,4) &_
ChrB(18) & ChrB(11) & ChrB(0) & ChrB(0) & ChrB(18) & ChrB(11) &_
ChrB(0) & ChrB(0) & ChrB(0) & ChrB(0) & ChrB(0) & ChrB(0) & ChrB(0) & ChrB(0) &_
ChrB(0) & ChrB(0)
For i = UnitHeight-1 To 0 Step -1 ' 曆經所有行
For ii = 0 To codeLen-1 ' 曆經所有字
For iii = 1 To UnitWidth ' 曆經所有像素
If Rnd * 99 + 1 >= cOdds Then ' 逐行、逐字、逐像素地輸出映像資料
Response.BinaryWrite vColorData(Mid(vCode(ii), i * UnitWidth + iii, 1))
Else ' 隨機產生雜點
Response.BinaryWrite vColorData(1-CInt(Mid(vCode(ii), i * UnitWidth + iii, 1)))
End If
Next
Next
Next
End Sub
Rem 對單個字的點陣進行幹擾
Rem 幹擾思想:在點陣範圍內隨機產生2個端點,進行連線,以位移較大的一方做橫軸,先將連線上的點刪除,再將被刪除點的縱軸方向上方或下方的點(隨機確定)移向被刪除點,移動後的空白用背景色補充
Function pcd_doubter(ByVal str,UnitWidth,UnitHeight,DotsLimit,tryCount,dbtTimes)
Randomize
Dim x1,x2,y1,y2,xOffSet,yOffSet,direction,flag,rows,step,yu,yuStr,i,ii,iii,f1,f2
For f1=1 To dbtTimes '幹擾次數
For f2=1 To tryCount '避免刪除有效點超過上限的嘗試次數限制
'隨機確定2個端點
x1 = int(Rnd*UnitWidth)
x2 = int(Rnd*UnitWidth)
y1 = int(Rnd*UnitHeight)
y2 = int(Rnd*UnitHeight)
'x,y位移量
xOffSet = Abs(x2-x1)
yOffSet = Abs(y2-y1)
If xOffSet >= yOffSet Then '以位移量較大方做橫軸
direction = "x"
ReDim ary(xOffSet) '用來記錄連線各點y值
'x2,y2儲存x值較大的點
If x2 < x1 Then
i = x1
x1 = x2
x2 = i
i = y1
y1 = y2
y2 = i
End If
'判斷從x1->x2在縱軸方向上是增是減
If y2 >= y1 Then
flag = 1
Else
flag = -1
End If
'下面計算連線上點的分布(先是平均分配各行的點,然後隨機分配剩餘的點到各行)
rows = yOffSet + 1 '所佔行數
step = (xOffSet+1) / rows '各行平均分配的點
yu = (xOffSet+1) Mod rows '剩餘的點數
ReDim ary2(rows-1) '用來記錄剩餘點的隨機分配
While yu > 0
i = int(Rnd*rows)
ary2(i) = ary2(i)&"." '被分配到的行則加一個字元"."
yu = yu - 1
WEnd
iii = 0
'將連線的點資訊記錄到數組
For i=0 To rows-1
For ii=1 To step+Len(ary2(i))
ary(iii) = y1 + i*flag
iii = iii + 1
Next
Next
ii = 0
'統計連線上有效點的數量
For i=0 To xOffSet
If pcd_getDot(x1+i,ary(i),str,UnitWidth) = "0" Then ii = ii + 1
Next
Else
'這裡是以y為橫軸,原理與x時相同
direction = "y"
ReDim ary(yOffSet)
If y2 < y1 Then
i = x1
x1 = x2
x2 = i
i = y1
y1 = y2
y2 = i
End If
If x2 >= x1 Then
flag = 1
Else
flag = -1
End If
rows = xOffSet + 1
step = (yOffSet+1) / rows
yu = (yOffSet+1) Mod rows
ReDim ary2(rows-1)
While yu > 0
i = int(Rnd*10)
If i < rows Then
ary2(i) = ary2(i)&"."
yu = yu - 1
End If
WEnd
iii = 0
For i=0 To rows-1
For ii=1 To step+Len(ary2(i))
ary(iii) = x1 + i*flag
iii = iii + 1
Next
Next
ii = 0
For i=0 To yOffSet
If pcd_getDot(ary(i),y1+i,str,UnitWidth) = "0" Then ii = ii + 1
Next
End If
'如未超過有效點上限則跳出迴圈,執行幹擾
If ii <= DotsLimit Then Exit For
Next
If direction = "x" Then
'隨機確定在縱軸方向上或下進行移動
If int(Rnd*10) > 4 Then
'變數連線上的點
For i=0 To xOffSet
'遍曆移動
For ii=ary(i) To 1 Step -1
Call pcd_setDot(x1+i,ii,str,pcd_getDot(x1+i,ii-1,str,UnitWidth),UnitWidth)
Next
'添補空白
Call pcd_setDot(x1+i,0,str,"1",UnitWidth)
Next
Else
For i=0 To xOffSet
For ii=ary(i) To UnitHeight-2
Call pcd_setDot(x1+i,ii,str,pcd_getDot(x1+i,ii+1,str,UnitWidth),UnitWidth)
Next
Call pcd_setDot(x1+i,UnitHeight-1,str,"1",UnitWidth)
Next
End If
Else
If int(Rnd*10) > 4 Then
For i=0 To yOffSet
For ii=ary(i) To 1 Step -1
Call pcd_setDot(ii,y1+i,str,pcd_getDot(ii-1,y1+i,str,UnitWidth),UnitWidth)
Next
Call pcd_setDot(0,y1+i,str,"1",UnitWidth)
Next
Else
For i=0 To yOffSet
For ii=ary(i) To UnitWidth-2
Call pcd_setDot(ii,y1+i,str,pcd_getDot(ii+1,y1+i,str,UnitWidth),UnitWidth)
Next
Call pcd_setDot(UnitWidth-1,y1+i,str,"1",UnitWidth)
Next
End If
End If
Next
pcd_doubter = str
End Function
Rem 得到某點的字元
Function pcd_getDot(x,y,str,UnitWidth)
pcd_getDot = Mid(str,x+1+y*UnitWidth,1)
End Function
Rem 設定某點的字元
Sub pcd_setDot(x,y,ByRef str,newDot,UnitWidth)
str = Left(str,x+y*UnitWidth) & newDot & Right(str,Len(str)-x-y*UnitWidth-1)
End Sub
Rem 將數字轉為bmp需要的格式 lens是目標位元組長度
Function Num2ChrB(num,lens)
Dim ret,i
ret = ""
While (num>0)
ret = ret & ChrB(num mod 256)
num = num / 256
WEnd
For i=Lenb(ret) To lens-1
ret = ret & chrB(0)
Next
Num2ChrB = ret
End Function
%>
儲存為code.asp
使用
<img src="code.asp" style="cursor:hand" id="code" onclick="document.getElementById('code').src='../inc/code.asp?pp='+ Math.random();" alt="看不清?點一下" />
驗證函式
CODE: Function codepass()
Dim CodeStr
CodeStr = Trim(request("CodeStr"))
If CStr(Session("GetCode")) = CStr(CodeStr) And CodeStr <> "" Then
codepass = True
'Session("GetCode")=empty
Else
codepass = False
'Session("GetCode")=empty
End If
End Function在伺服器端驗證的時候 <%If Trim(Request.Form("validate_code"))=Empty Or Trim(Session("getCode")) <>Trim(Request.Form("validate_code")) Then
response.write(" <script language=javascript>alert('請注意正確輸入驗證碼');Javascript:window.history.go(-1); </script>")
response.end
end if%>
<%
Option Explicit
Response.buffer = True
NumCode (8) '註:1,4,7,10,13,16為彩色背景型 2,5,8,11,14,17為黑白型 3,6,9,12,15,18為噪點型
Function NumCode(CodeType)
Response.Expires = -1
Response.AddHeader "Pragma", "no-cache"
Response.AddHeader "cache-ctrol", "no-cache"
On Error Resume Next
Dim zNum, rNum, i, j, listnum, listcode
Dim Ados, Ados1
listcode = "0123456789abcdefghijklmnopqrstuvwxyz"
Randomize Timer
Dim zimg(6), NStr
For i = 0 To 5
rNum = CStr(CInt(35 * Rnd)) '將35改為9即為使用純數字密碼
zimg(i) = rNum
listnum = listnum & Mid(listcode, rNum + 1, 1)
Next
Session("CheckCode") = listnum
Dim Pos
Set Ados = Server.CreateObject("Adodb.Stream")
Ados.Mode = 3
Ados.Type = 1
Ados.Open
Set Ados1 = Server.CreateObject("Adodb.Stream")
Ados1.Mode = 3
Ados1.Type = 1
Ados1.Open
Ados.LoadFromFile (Server.mappath("../images/body" & CodeType & ".Fix"))
Ados1.write Ados.read(2880)
For i = 0 To 5
Ados.Position = (35 - zimg(i)) * 480
Ados1.Position = i * 480
Ados1.write Ados.read(480)
Next
Ados.LoadFromFile (Server.mappath("../images/head.fix"))
Pos = LenB(Ados.read())
Ados.Position = Pos
For i = 0 To 15 Step 1
For j = 0 To 5
Ados1.Position = i * 32 + j * 480
Ados.Position = Pos + 30 * j + i * 270
Ados.write Ados1.read(30)
Next
Next
Response.ContentType = "image/BMP"
Ados.Position = 0
Response.BinaryWrite Ados.read()
Ados.Close: Set Ados = Nothing
Ados1.Close: Set Ados1 = Nothing
'If Err Then Session("CheckCode") = "999999"
End Function
%>