PHP - Set Time Limit In Safe Mode

Unless buffer overflows or breaking out of code to perform a new command are problems that have been solved....

I am trying to figure out the proper PHP method for setting a boundary on a variable within a script. I have this variable $name which is fed a value from $_POST['name'] from a form field. Now this form field is limited in the HTML to accept only 20 characters, but someone could easily edit the form or outgoing post data. So I want to know how to limit the variable size in the script. In other languages it could be something like this: var name(20). So how do I do that in PHP?

using this below is it safe against hackers?

Code: [Select]
$post_id = intval($_GET['report']);
if ($post_id < 1)
message($lang_common['Bad request']);
query:

Code: [Select]
$result = $db->query('SELECT subject, forum_id FROM '.$db->prefix.'topics WHERE id='.$topic_id) or error('Unable to fetch topic info', __FILE__, __LINE__, $db->error());
should i escape my $topic_id ?

Code: [Select]
$stick_topic = isset($_POST['stick_topic']) ? '1' : '0';
does this need to be escaped while entering the database or no because the values could only be 1 or 0 ?

srry it's just i got hacked so i am trying to do my security #1

I have a button that uses $_POST to send information to another page.  The data is in a hidden input so it's not possible for users to change information.  I have nothing to check if the data is correct on the other page.  Is it still possible for people to change the $_POST data though?  Or somehow send false $_POST data to the other page?

Hello all.

Just wanted to run this past you guys to see if I am missing anything important. I am making a script that I plan to allow a lot of other people around the web to use, so I want to make sure it's as bullet proof as possible.

I am passing two values and grabbing them with a _GET, one is a big number, and the other is only letters and 8 characters long.

her's my code so far.

Code: [Select]
<?php
    $clan = $_GET['clanid'];
    // make sure its an INT
        //if(isint($clan)){
        if(ereg("[^0-9]", $clan)){
            //im an int.
            echo ("ERROR Invalid CLANID");
            die;          
        }
    
    // make sure its a 8 letter only word.
    $style=$_GET['style'];
        
        // cut style down to 8 characters long.
        $style=substr($style, 0, 8);
        
        if(ereg("[^a-zA-Z]+", $style)) {
            // Contains only letters.
            echo("ERROR Invalid STYLE NAME");
            die;          
        }   
    
?>

to my noob php eye's it looks pretty solid, I cant think of any way a malicious user could get past it, but like I said, thought I would run it past you guys first , you can never be to careful.

Hi guys, I have been using the same code for years now to include my default page and pull content into my layouts.   I found the code online and its a bit confusing so was just wondering if its still safe to use, and is it all needed nowadays? or is there a simpler way i could be doing this?   Thanks for any help

<?php

    if (isset($_GET['nav'])) 
{
    if (strpos($_GET['nav'], "/")) 
{
    $direc = substr(str_replace('..', '', $_GET['nav']), 0, strpos($_GET['nav'], "/")) . "/";
    $file = substr(strrchr($_GET['nav'], "/"), 1);
    if (file_exists($direc.$file.".php")) 
{
    require($direc.$file.".php");
} else {
    require("error.php");
}
} else {
    if (file_exists(basename($_GET['nav']).".php")) 
{
    require(basename($_GET['nav']).".php");
} else {
    require("error.php");
}
}
} else {
    require("links.php");
}
?>

Advice please.

I am setting up a new machine here and I can't remember which to download.

What information do you need to be aware of to know whether to install 'non thread safe' or 'thread safe'.  I did some googling but didn't find anything that was clear. 

And is 5.3 good to go or should I stick with 5.2.

Thanks in advance for your input!

I am using this script for "remember me" option:
                      if (isset($_POST['rememberme']))
                        {
                          /* Set cookie to last 1 year */
                          setcookie('username', $_POST['user_name'], time() + 60 * 60 * 24 * 365);
                          setcookie('password', sha1($_POST['user_pass']), time() + 60 * 60 * 24 * 365);
                        }

Is it safe to save user data in cookie or there is better way? Can somebody steal password if there is more than one user at same computer? What do you suggest?

Hi,     Recently I've been trying writing a safe password hash and I wanted to know that if I use an MD5 hash at the end, just so it will be like some short of "packed",so instead of saving a 128 string, I'll use md5 to "pack" it into 32 characters and save up to 96 characters.   I know MD5 isn't safe and all, but the question is, does it lower the security ?   Also, would be happy for feedbacks about my password hash

function hash_($input,$key) {

     $op=hash("whirlpool",hash("sha512",$key) . "$" . $input . "$" . hash("sha512",$key));

I am building an XML string to send to another server.

The manual I am going off of says,

Quote

NOTE:
    * XML has a special set of characters that cannot be used in normal XML strings. These characters a
      Special Character    Equivalent
      &    &amp;
      <    &lt;
      >    &gt;
      "    &quot;
      '    &#39;


It goes on to say...
Quote

# To avoid problems with special characters, URLEncode special characters (example: ~ ! @ # % ^ &) before sending to the IS Gateway
# If you are using POST method, UTF-8 encoding must be used.



I am unsure of what to do based on the information above?!

It looks like I might want to use urlencode??

Also, maybe I need either htmlentities (or possibly htmlspecialchars)??

Please enlighten me (and help protect my data)!! 

Thanks,



Debbie

Hi,

I am using parameterized queries on my code, here's the relevant part

Code: [Select]
$params=$_POST['ITGtable'];

$tsql2 = "SELECT COLUMN_NAME, DATA_TYPE, ORDINAL_POSITION,
  COLUMN_DEFAULT, CHARACTER_MAXIMUM_LENGTH, IS_NULLABLE
  FROM INFORMATION_SCHEMA.COLUMNS
  WHERE TABLE_NAME=?";

/* Execute the statement with the specified parameter value.
Display the returned data if no errors occur. */
$stmt2 = sqlsrv_query( $conn, $tsql2, $params);
if( $stmt2 === false )
{
     echo "Statement 2 could not be executed.\n";
     die( print_r(sqlsrv_errors(), true));
}
else
{
     $qty = sqlsrv_fetch_array( $stmt2);
}
Do I really have to sanitize $_POST['ITGtable'] for apostrophe, semicolon, etc, to avoid SQL injection problems? Or just with above code I should be safer (I did not say safe) against SQL injection? And if the answer is "No", what could be the sanitize code of function? I am using sqlsrv and MS-SQL database engine; most of the functions we have for sanitize inputs on MySQL are not available for MS-SQL.

Thanks in advance,

Hey guys!
I have a doubt and this is a question that relates Flash and PHP...

I have a flash (swf) file that grabs/sends variables from/to php.
That swf file is FULLY encrypted and the paths to the PHP urls are also encrypted.

Is there any other way a hacker could find out where and which my PHP files are located/named?

Any ideas, suggestions?
Thanks in advance!
Cheers,

I am using seo friendly urls so when someone makes a post named "this is a post" the url will point to www.example.com/topic/this_is_a_post

But when the user enters a character in their post name that means something in a url(? /) it obviously breaks. How can i make the urls safe from this without str_replace as i want to keep the characters.

Hi guys, I've been around here for a few years, but for some reason my other account doesn't seem to 'exist' anymore which was real annoying. I also noticed the captcha here was kind of buggy has anyone else been getting that? I'd enter it in case sensative 9-10 times before it would finally work.   Anyways, I've been looking through a lot of research in upgrading my server from Mysql to Mysqli funtions. What I am curious about though is other peoples opinions and thoughts on how to make user input safer. For the time being I've just been using mysql_real_escape_string and htmlspecialchars. I've done quite a bit of research on this and there really isn't much for any guides on how to keep your data clean and safe. I've seen a lot of posts that anymore these two functions are not enough to secure your data. So I'm curious what people in this community are doing (annonomysly) to keep your user input safe. I'm also looking into prepared statements as well with Mysqli. Anyways any responses are much appreciated, would love to chat with you guys about this!   Does anyone know if there was some deal with why I can't access my origional account? I entered in all of the only 5 email addresses I use. It said it sent an email to the one, but it never appeared in junk/inbox.

I have created this login class (In all honesty this is the most commented and well structured class I have ever written, I usualy just use random functions in a functions.php file, which works but this felt good when I finished it )

I just wanted some advice to how safe and whether the way I have done this is 'good practise', or if there is anything I should add to future proof it.

This is the class:
Code: [Select]
<?php
/* 
Author: Craig Dennis
File: user_session.class.php
Purpose: Flexible user login class that handles logging in, checking a user is logged in, and logging out.

NOTE TO USE THIS CLASS YOU MUST ALREADY HAVE ALREADY CONNECTED TO THE DATABASE

Include this file at the top of each page you wish to protect
 include("inc/user_session.class.php"); //(This could be put at the top of a global include file)
 
Use the following code to check the user is logged in:
 $user_session = new user_session; //(This could be put at the top of a global include file)
 $user_session->validate_user(); //(This should only be left on the pages you wish to check for user validation)
 
You will want to use the public redirect_if_logged_in() function instead of validate_user() on the login page like this:
 $user_session->redirect_if_logged_in(); //(This will redirect a user from the current page to the specified landing page)
*/
class user_session{
// Change these variables below if the table and fields in your database do not match
public $t_name = "admins";
public $t_user = "username";
public $t_pass = "password";
public $t_lastlogin = "last_login"; //set $t_lastlogin = NULL if you do not have this field in your database

//Change $login_page and $landing_page if your page names are different to this one
public $login_page = "login.php";
public $landing_page = "logged_in.php";

//Change $log_in_error_msg if you wish to change the general error message when the user is unable to log in
public $log_in_error_msg = "The username or password you have entered is incorrect or does not exist";

//Do not touch anything below unless you know what your doing

/*
 * logged_in_user()
 * Returns value of the current logged in username
 */
public function logged_in_user(){
return $_SESSION['user_username'];
}

/*
 * log_in()
 * Takes 2 parameters ($username, $password)
 * Attempts to log in with the provided credentials, on success, the username and password are saved in the session for future testing
 */
public function log_in($username, $password){
$username = stripslashes(mysql_real_escape_string($username));
$password = stripslashes(mysql_real_escape_string($password));

$query_login = mysql_query("SELECT * FROM ".$this->t_name."
  WHERE ".$this->t_user."='$username' AND ".$this->t_pass."='$password'");;

$login_accepted = mysql_num_rows($query_login);

if($login_accepted == 1){
if($t_lastlogin != NULL){
$query_update_last_login = mysql_query("UPDATE ".$this->t_name." SET ".$this->t_lastlogin."='".time()."'
WHERE ".$this->t_user."='$username'");
}
$_SESSION['user_username'] = $username;
$_SESSION['user_password'] = $password;
return true;
}else{
return false;
}
}

/*
 * check_user()
 * Returns true if the current session credentials can be found in the database, otherwise returns false
 */
public function check_user(){
$query_login = mysql_query("SELECT * FROM ".$this->t_name."
  WHERE ".$this->t_user."='".$_SESSION['user_username']."' 
AND ".$this->t_pass."='".$_SESSION['user_password']."'");

$login_accepted = mysql_num_rows($query_login);

if($login_accepted == 1){
return true;
}else{
return false;
}
}

/*
 * validate_user()
 * Returns true if the current session credentials can be found in the database, otherwise logs user out and returns false
 */
public function validate_user(){
$login_accepted = $this->check_user();

if($login_accepted == 1){
return true;
}else{
$this->log_out();
return false;
}
}

/*
 * redirect_if_logged_in()
 * Redirects the user to the specified landing page if the user is logged in
 */
public function redirect_if_logged_in(){
if($this->check_user()){
header("Location: ".$this->landing_page);
}
}

/*
 * log_out()
 * Logs the user out by setting the session credentials to an empty string and redirecting them to the specified login page
 */
public function log_out(){
$_SESSION['user_username'] = "";
$_SESSION['user_password'] = "";
header("Location: ".$this->login_page);
}
}
?>

Any comments or advice are appreciated.