1 / 9

Protecting Files with .htaccess and PHP: A Guide

This document outlines methods for protecting files using .htaccess for Apache servers and PHP sessions or cookies. It includes syntax examples for implementing simple authentication with .htaccess, using AuthType, AuthUserFile, and AuthName. Additionally, it discusses session management in PHP for secure access and cookie handling for persistent logins. The guide also details how to handle file uploads with PHP, including error codes and uploading multiple files. Ensure your file uploads are safe and user data is protected effectively.

vivi
Télécharger la présentation

Protecting Files with .htaccess and PHP: A Guide

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Web ProgrammingWeek 10 Old Dominion University Department of Computer Science CS 418/518 Fall 2010 Martin Klein <mklein@cs.odu.edu> 11/02/10

  2. Protect Files - htaccess • Apache syntax: • place file .htaccess into directory you want to protect • specify: • AuthType Basic|Digest • AuthUserFile /path/to/file/containing/user/credentials • AuthName “MyAuthExampleName” • restrictions • Example: • AuthType Basic • AuthName “Rams Free Zone” • AuthUserFile /home/mklein/cs518passwd • <LIMIT GET POST> • Require valid-user • </LIMIT> htpasswd -c /home/mklein/cs518passwd mklein Default: crypt(), others: md5, sha, plain (BOOO!) See: man htpasswd http://mln-web.cs.odu.edu/~mklein/cs518/restricted

  3. Protect Files – the PHP Way • Sessions • session_start(); • associative array $_SESSION • test, e.g. • if(isset ($_SESSION[‘logged’]) && $_SESSION[‘logged’] == 1) { • echo “you are logged in”; • } else { • echo “you need to login!”; • } • NOTE: • can transport session from page to page • but session is destroyed when browser closed (session_destroy()) • server sided hence user is NOT able to modify session data • see example, ch12 (book) ch11 (sample code on website)

  4. Protect Files – the PHP Way • Cookies • setcookie(name, value, expiration); • name: used to retrieve cookie • value: value stored in cookie (username, last visit) • expiration: date when cookie will expire/be deleted(if not set, cookie is treated as session cookie – removed at browser restart) • setcookie(‘username’,”mklein”, time() + 60) // lasts 60s • setcookie(‘username’,”mklein”, 60) // 60s after midnight 1/1/1970 - destroy • associative array $_COOKIE • test, e.g. • if($_COOKIE[‘username’] ! =“”)) { • echo “your name is: $_COOKIE[‘username’]”; • } else { • echo “who are you?”; • } • NOTE: • persistent login, for example • client sided hence user IS able to modify cookie data

  5. File Upload with PHP • HTML form based • POST method • Content Type (enctype) attribute: multipart/form-data(and not application/x-www-form-urlencoded) • define MAX_FILE_SIZE [in B] in hidden filed, must precede: • input field type: file • its name is important! • Example: • <form enctype="multipart/form-data" action=“file_upload.php" method="POST"> • <input type="hidden" name="MAX_FILE_SIZE" value="30000" /> • Send this file: <input name=“mkfile" type="file" /> • <input type="submit" value="Send File" /> • </form>

  6. File Upload with PHP • associative array $_FILES • $_FILES[‘mkfile’][‘name’] – original name from client • $_FILES[‘mkfile’][‘type’] – mime type if provided • $_FILES[‘mkfile’][‘size’] – size in B • $_FILES[‘mkfile’][‘tmp_name’] – tmp file name on server • $_FILES[‘mkfile’][‘error’] – error code

  7. File Upload with PHP – Error Codes • UPLOAD_ERR_OK[0] • no error, file upload successful • UPLOAD_ERR_INI_SIZE [1] • uploaded file exceeds upload_max_filesize in php.ini • UPLOAD_ERR_FORM_SIZE [2] • uploaded file exceeds MAX_FILE_SIZE specified in HTML form • UPLOAD_ERR_PARTIAL [3] • file was only partially uploaded • UPLOAD_ERR_NO_FILE [4] • no file uploaded • UPLOAD_ERR_NO_TMP_DIR [6] • missing temporary folder • UPLOAD_ERR_CANT_WRITE [7] • write file to disk failed • UPLOAD_ERR_EXTENSION[8] • PHP extension stopped the file upload

  8. File Upload with PHP Example: <?php$uploaddir = '/home/mklein/public_html/uploads/';$uploadfile = $uploaddir . basename($_FILES[‘mkfile']['name']);if (move_uploaded_file($_FILES[‘mkfile']['tmp_name'], $uploadfile)) {    echo "File is valid, and was successfully uploaded.\n";} else {    echo "Possible file upload attack!\n";}echo 'Here is some more debugging info:';print_r($_FILES);?>

  9. Upload Multiple Files with PHP • similar to single file upload • use array of file names • Example: • <form enctype="multipart/form-data" action=“file_upload.php" method="POST"> • Send these files:<br> • <input name=“mkfile[]" type="file" /> //file1.txt; 13KB • <input name=“mkfile[]" type="file" /> //file2.png; 42KB • <input name=“mkfile[]" type="file" /> //file3.pdf; 113KB • <input type="submit" value="Send Files" /> • </form> • $_FILES[‘mkfile’][‘name’][0] eq file1.txt • $_FILES[‘mkfile’][‘name’][1] eq file2.png • $_FILES[‘mkfile’][‘name’][2] eq file3.pdf • $_FILES[‘mkfile’][‘size’][0] eq 13KB • $_FILES[‘mkfile’][‘size’][1] eq 42KB • $_FILES[‘mkfile’][‘size’][2] eq 113KB

More Related