username and password validation

[Eugene Anthony]

Is this method of validation for password and username considered to be
secured. In my previous post I was given a solution that uses command
object and the values are parsed by parameters. But the solution only
worked well for insert and delete, but not select.

<%
if Request.QuerySt ring("Action") = 1 then
username = Trim(request.fo rm("username") )
password = Trim(request.fo rm("password") )
if username <> "" and password <> "" then
set conn = server.CreateOb ject("ADODB.Con nection")
conn.connection string = "Provider=Micro soft.Jet.OLEDB. 4.0;Data
Source=" & Server.MapPath( "/db/upload/stelladb.mdb") & ";"
conn.open
set rs = server.CreateOb ject("ADODB.Rec ordset")
sql = "SELECT Count(*) FROM Account WHERE username='" &
username & "' AND password='" & password & "'"
rs.open sql,conn,3,3
if rs.Fields(0) = 1 then
session("boolea n") = "true"
response.redire ct "main.asp"
else
session("boolea n") = "false"
response.write "<center><f ont class='error'>E rror: Invalid
Authentication</font></center><br><br> "
end if
conn.close
Set conn = nothing
end if
end if
%>

Eugene Anthony

*** Sent via Developersdex http://www.developersdex.com ***

[Kyle Peterson]

well, your not requiring a case sensative password and I think your open to
SQL injection attacks even with using a count statement so probably no

"Eugene Anthony" <so***********@ yahoo.com> wrote in message
news:%2******** ********@TK2MSF TNGP04.phx.gbl. ..

Is this method of validation for password and username considered to be
secured. In my previous post I was given a solution that uses command
object and the values are parsed by parameters. But the solution only
worked well for insert and delete, but not select.

<%
if Request.QuerySt ring("Action") = 1 then
username = Trim(request.fo rm("username") )
password = Trim(request.fo rm("password") )
if username <> "" and password <> "" then
set conn = server.CreateOb ject("ADODB.Con nection")
conn.connection string = "Provider=Micro soft.Jet.OLEDB. 4.0;Data
Source=" & Server.MapPath( "/db/upload/stelladb.mdb") & ";"
conn.open
set rs = server.CreateOb ject("ADODB.Rec ordset")
sql = "SELECT Count(*) FROM Account WHERE username='" &
username & "' AND password='" & password & "'"
rs.open sql,conn,3,3
if rs.Fields(0) = 1 then
session("boolea n") = "true"
response.redire ct "main.asp"
else
session("boolea n") = "false"
response.write "<center><f ont class='error'>E rror: Invalid
Authentication</font></center><br><br> "
end if
conn.close
Set conn = nothing
end if
end if
%>

Eugene Anthony

*** Sent via Developersdex http://www.developersdex.com ***

[Justin Piper]

On Fri, 16 Jun 2006 13:24:07 -0500, Eugene Anthony
<so***********@ yahoo.com> wrote:

Is this method of validation for password and username considered to be
secured.
No, I'm afraid it is not. Your code as written is vulnerable to a
widely-known attack which would allow an attacker to easily log in as any
arbitrary user. The problem is with these lines:
set rs = server.CreateOb ject("ADODB.Rec ordset")
sql = "SELECT Count(*) FROM Account WHERE username='" &
username & "' AND password='" & password & "'"
rs.open sql,conn,3,3

By directly embedding the values of the ``username`` and ``password``
variables in your SQL statement, you are effectively executing arbitrary
code supplied by the client. Instead, you should use the ADO Command
object to pass arguments to a query.

Set cmd = CreateObject("A DODB.Command")
With cmd
Set .ActiveConnecti on = conn
.CommandType = adCmdText
.CommandText = "SELECT COUNT(*) FROM Account WHERE username=? AND
password=?"
.Parameters.App end cmd.CreateParam eter("username" , adVarChar,
adParamInput, 50, username)
.Parameters.App end cmd.CreateParam eter("password" , adVarChar,
adParamInput, 50, password)
Set rst = .Execute()
End With

Note that for this example you'll need to declare the ADO constants if you
haven't already. See http://www.aspfaq.com/show.asp?id=2112 if you aren't
familiar with the ADO constants.

--
Justin Piper
Bizco Technologies
http://www.bizco.com/

[Mike Brind]

Eugene Anthony wrote:

Is this method of validation for password and username considered to be
secured. In my previous post I was given a solution that uses command
object and the values are parsed by parameters. But the solution only
worked well for insert and delete, but not select.

<%
if Request.QuerySt ring("Action") = 1 then
username = Trim(request.fo rm("username") )
password = Trim(request.fo rm("password") )
if username <> "" and password <> "" then
set conn = server.CreateOb ject("ADODB.Con nection")
conn.connection string = "Provider=Micro soft.Jet.OLEDB. 4.0;Data
Source=" & Server.MapPath( "/db/upload/stelladb.mdb") & ";"
conn.open
set rs = server.CreateOb ject("ADODB.Rec ordset")
sql = "SELECT Count(*) FROM Account WHERE username='" &
username & "' AND password='" & password & "'"
rs.open sql,conn,3,3
if rs.Fields(0) = 1 then
session("boolea n") = "true"
response.redire ct "main.asp"
else
session("boolea n") = "false"
response.write "<center><f ont class='error'>E rror: Invalid
Authentication</font></center><br><br> "
end if
conn.close
Set conn = nothing
end if
end if
%>

If you are uncomfortable using the command object with parameters,
there is a much easier way to do this - use a saved parameter query.

Open your Access database, and go to the Query tab. Choose "Create
Query in Design View". A dialogue box appears offering you to select
tables. Close it. In the top left corner of your menus, you see
"SQL". Click that.

In the new pane that just opened, type (or copy and paste):

SELECT Count(*) FROM Account WHERE username=[p1] AND password=[p2]

Save it as qGetUser.

In your code do this:

<%
if Request.QuerySt ring("Action") = 1 then
p1= Trim(request.fo rm("username") )
p2= Trim(request.fo rm("password") )
if p1<> "" and p2<> "" then
set conn = server.CreateOb ject("ADODB.Con nection")
conn.connection string = "Provider=Micro soft.Jet.OLEDB. 4.0;Data
Source=" & Server.MapPath( "/db/upload/stelladb.mdb") & ";"
conn.open
set rs = server.CreateOb ject("ADODB.Rec ordset")
conn.qGetUser p1,p2,rs
If rs(0) = 1 Then
session("boolea n") = "true"
.....
etc

Doing it this way means you still don't have to delimit values in
concatenated dynamic sql (same as the command and parameters), and you
are protected from sql injection in the same way. It's a lot less code
that the command object version, and if you ever feel the need to
change the name of one of your database fileds, you only have ot go to
the database to do it - you son't have ot chase around ASP code finding
all instances of the old field name.

Saved parameter queries work just as easily for inserts and updates
too.

--
Mike Brind

[Eugene Anthony]

In asp I did this:

<%
if Request.QuerySt ring("Action") = 1 then
on error resume next
p1 = Trim(request.fo rm("username") )
p2 = Trim(request.fo rm("password") )
if username <> "" and password <> "" then
set conn = Server.CreateOb ject("ADODB.Con nection")
conn.open "Provider=Micro soft.Jet.OLEDB. 4.0;Data Source=" &
Server.MapPath( "/db/upload/stelladb.mdb") & ";"
set rs = Server.CreateOb ject("ADODB.Rec ordset")
conn.qGetUser p1,p2,rs
if rs(0) = 1 then
session("boolea n") = "true"
response.redire ct "main.asp"
else
session("boolea n") = "false"
response.write "<center><f ont class='error'>E rror: Invalid
authentication</font></center><br><br> "
end if
if Err.number <> 0 then
Response.Write( Err.number & ":" & Err.Description & "<br>")
end if
on Error goto 0
conn.close
Set conn = nothing
end if
end if
%>
and in ms access I created the sql query:

SELECT Count(*) FROM Account WHERE username=[p1] AND password=[p2]
but when I access the page its going into a loop.

Eugene Anthony

*** Sent via Developersdex http://www.developersdex.com ***

[Eugene Anthony]

I did test qGetUser in MS Access, supplied the values and it works.
However using asp it is going into a loop.

Eugene Anthony

*** Sent via Developersdex http://www.developersdex.com ***

[Mike Brind]

Eugene Anthony wrote:

I did test qGetUser in MS Access, supplied the values and it works.
However using asp it is going into a loop.

Get rid of on error resume next to see where it goes wrong. On Error
Resume Next has no place in code until it has been fully tested and is
working properly. It hides errors.

Look, the easiest way I find to produce ASP pages is the following:

1. Add Option Explicit statement to the top of a page.
2. Produce ASP code without any html
3. Test and debug
4. Once it's working as it should, add error handling
5. Test and debug
6. Add html (or move tested code to html page already constructed)
7. Test and debug.
8. Once working and ready for deployment, remove Option Explicit
statement

What's the name of the page you have put this code in? Is it main.asp?
Where is the loop? On the Redirect?

--
Mike Brind

[Eugene Anthony]

This is the complete code for login.asp. inc_Common.asp contains all the
variable.
<%Option Explicit%>
<!--#INCLUDE FILE="inc_Commo n.asp" -->
<%
if Request.QuerySt ring("Action") = 1 then
'on error resume next
p1 = Trim(request.fo rm("username") )
p2 = Trim(request.fo rm("password") )
if username <> "" and password <> "" then
set conn = Server.CreateOb ject("ADODB.Con nection")
conn.open "Provider=Micro soft.Jet.OLEDB. 4.0;Data Source=" &
Server.MapPath( "/db/upload/stelladb.mdb") & ";"
set rs = Server.CreateOb ject("ADODB.Rec ordset")
conn.qGetUser p1,p2,rs
if rs(0) = 1 then
session("boolea n") = "true"
response.redire ct "main.asp"
else
session("boolea n") = "false"
response.write "<center><f ont class='error'>E rror: Invalid
authentication</font></center><br><br> "
end if
' if Err.number <> 0 then
' Response.Write( Err.number & ":" & Err.Description & "<br>")
' end if
'on Error goto 0
conn.close
Set conn = nothing
end if
end if
%>
<html>
<head>
<title>Login</title>
</head>
<body bgcolor="#FFFFF F">
<center>
<table width="291" border="0" cellpadding="0" cellspacing="0"
height="20">
<tr>
<td class="header" width="420"><fo nt
class="PopTitle "><center>Login </center></font></td>
</tr>
<tr>
<td height="50">
<br>
<center>
<form name="form1" method="post" action="login.a sp?Action=1">
<table border="0" cellpadding="2" cellspacing="0" width="223">
<tr>
<td width="150">Use rname</td>
<td width="148">
<input type="text" name="username"
style="backgrou nd:FFFFF9; border:1px solid; size="20" size="20">
</td>
</tr>
<tr>
<td width="150">Pas sword</td>
<td width="148">
<input type="password" name="password"
style="backgrou nd:FFFFF9; border:1px solid; size="20" size="20">
</td>
</tr>
<tr>
<td width="298" colspan="2">
<table border="0" cellpadding="2" cellspacing="0"
width="100%">
<tr>
<td width="25%"></td>
<td width="25%">
<input type="Submit" style="backgrou nd:EEEEEE;
border:1px solid; " value="Submit" name="Submit">
</td>
<td width="22%">
<input type="Reset" value="Reset"
style="backgrou nd:EEEEEE; border:1px solid; " size="20" name="Reset">
</td>
<td width="28%"></td>
</tr>
</table>
</td>
</tr>
</table>
</form>
</center>
</td>
</tr>
</table>
</center>
</body>
</html>
Eugene Anthony

*** Sent via Developersdex http://www.developersdex.com ***

[Eugene Anthony]

I found the error:

In my <!--#INCLUDE FILE="inc_Commo n.asp" -->

I have this code

<%
if session("boolea n") = "false" or session("boolea n") = "" then
response.redire ct "login.asp"
end if
%>

and this caused the problem.

Eugene Anthony

*** Sent via Developersdex http://www.developersdex.com ***

[Bob Barrows [MVP]]

Justin Piper wrote:

By directly embedding the values of the ``username`` and ``password``
variables in your SQL statement, you are effectively executing
arbitrary code supplied by the client. Instead, you should use the
ADO Command object to pass arguments to a query.

Set cmd = CreateObject("A DODB.Command")
With cmd
Set .ActiveConnecti on = conn
.CommandType = adCmdText
.CommandText = "SELECT COUNT(*) FROM Account WHERE username=?
AND password=?"
.Parameters.App end cmd.CreateParam eter("username" , adVarChar,
adParamInput, 50, username)
.Parameters.App end cmd.CreateParam eter("password" , adVarChar,
adParamInput, 50, password)
Set rst = .Execute()
End With

It can be done more simply than this, especially with Jet which does not
support output or return parameters:
http://groups-beta.google.com/group/...e36562fee7804e

--
Microsoft MVP - ASP/ASP.NET
Please reply to the newsgroup. This email account is my spam trap so I
don't check it very often. If you must reply off-line, then remove the
"NO SPAM"