rfc:session-use-strict-mode

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rfc:session-use-strict-mode [2016/07/04 22:27] – created yohgakirfc:session-use-strict-mode [2016/07/28 18:29] – Moved to "under discussion", since voting is currently closed ocramius
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-====== PHP RFC: Your Title Here ====== +====== PHP RFC: Enable session.use_strict_mode by default ====== 
-  * Version: 0.9+  * Version: 1.0
   * Date: 2016-07-05   * Date: 2016-07-05
   * Author: Yasuo Ohgaki <yohgaki@ohgaki.net>   * Author: Yasuo Ohgaki <yohgaki@ohgaki.net>
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 ===== Introduction ===== ===== Introduction =====
-Due to HTTP cookie implementation, it is easy to create unchangeable/undeletable cookies via JavaScript injections. Single JavaScript injection vulnerability allows attackers to steal user session forever without session.use_strict_mode=1.+Due to HTTP cookie implementation, it is easy to create unchangeable/undeletable cookies via JavaScript injections. Single JavaScript injection vulnerability or cookie storage modification via physical access to the client allows attackers to steal user session forever without session.use_strict_mode=1. 
 + 
 +NOTE: When multiple cookies are valid for a request, browser sends a highest precedence cookie. Cookie sent by browsers differs browser by browser because there is no cookie precedence standard. Attacker can exploit this browser behavior to set unchangeable cookies by using httponly, secure, domain and path cookie attributes. Security impact differs according to web site setup, used browser and session handling code. 
  
 ===== Proposal ===== ===== Proposal =====
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 in hard coded, php.ini-*. in hard coded, php.ini-*.
 +
 +Document deprecation of obsolete session save handler API that does not support session.use_strict_mode.
 +
 +    * PS_FUNCS
 +
 +===== Performance Impact =====
 +
 +session.use_strict_mode=1 requires
 + 
 +  * Session ID existence validation. (Additional query to session data storage may be needed depending on save handler implementation.)
 +  * New session ID regeneration required when nonexistent session ID is passed.
 +
 +Files save handler will not be affected much, but external session data storage may have noticeable impact.
  
 ===== Backward Incompatible Changes ===== ===== Backward Incompatible Changes =====
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   * https://wiki.php.net/rfc/precise_session_management (Declined)   * https://wiki.php.net/rfc/precise_session_management (Declined)
  
-However, lost sessions are far better than stolen sessions.+However, lost sessions are far better than stolen sessions. 
  
-3rf party session handlers must implement session ID validation handler for session.use_strict_mode=1 to work actually. i.e. PS_FUNCS_SID or PS_FUNCS_UPDATE_TIMESTAMP must be used. PS_FUNCS_UPDATE_TIMESTAMP is strongly recommended.+When attackers set unchangeable session ID cookie for a user, the user will not be able to get valid session ID. i.e. Cannot login via attacker supplied unchangeable session ID, etc. 
 + 
 +3rd party session save handlers must implement session ID validation handler for session.use_strict_mode=1 to work actually. i.e. 3rd party session save handlers must use PS_FUNCS_SID or PS_FUNCS_UPDATE_TIMESTAMP. **PS_FUNCS_UPDATE_TIMESTAMP is strongly recommended.**
  
  
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 ===== Future Scope ===== ===== Future Scope =====
  
-Session ID should be managed by TTL timestamp precisely in order to session ID is managed correctly.+  * Session ID should be managed by TTL timestamp in order to manage session ID correctly and precisely. 
 +  * Remove session.use_strict_mode setting and enable it always. 
 +  * Remove session_regenerate_id()'s immediate session ID data removal option. i.e. Manage session data lifetime by TTL. 
 +  * Remove additional session data storage access by extending session save handler API.
  
-===== Proposed Voting Choices =====+===== Vote =====
  
-This project requires a 2/3+This project requires 2/3 majority
  
 +<doodle title="Enable session.use_strict_mode by default" auth="Yasuo Ohgaki" voteType="single" closed="true">
 +   * Yes
 +   * No
 +</doodle>
  
 +Vote starts 2016/7/12, ends 2016/07/19 23:59:59 UTC.
  
 ===== Patches and Tests ===== ===== Patches and Tests =====
rfc/session-use-strict-mode.txt · Last modified: 2020/08/01 23:51 by carusogabriel

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