from small one page howto to huge articles all in one place
 

search text in:





Poll
Which linux distribution do you use?







poll results

Last additions:
using iotop to find disk usage hogs

using iotop to find disk usage hogs

words:

887

views:

102605

userrating:

average rating: 1.7 (85 votes) (1=very good 6=terrible)


May 25th. 2007:
Words

486

Views

217325

why adblockers are bad


Workaround and fixes for the current Core Dump Handling vulnerability affected kernels

Workaround and fixes for the current Core Dump Handling vulnerability affected kernels

words:

161

views:

98041

userrating:

average rating: 1.3 (28 votes) (1=very good 6=terrible)


April, 26th. 2006:

Druckversion
You are here: manpages





SSL_CTX_sess_set_get_cb

Section: OpenSSL (3)
Updated: 2015-01-15
Index Return to Main Contents
 

NAME

SSL_CTX_sess_set_new_cb, SSL_CTX_sess_set_remove_cb, SSL_CTX_sess_set_get_cb, SSL_CTX_sess_get_new_cb, SSL_CTX_sess_get_remove_cb, SSL_CTX_sess_get_get_cb - provide callback functions for server side external session caching  

SYNOPSIS

 #include <openssl/ssl.h>

 void SSL_CTX_sess_set_new_cb(SSL_CTX *ctx,
                              int (*new_session_cb)(SSL *, SSL_SESSION *));
 void SSL_CTX_sess_set_remove_cb(SSL_CTX *ctx,
           void (*remove_session_cb)(SSL_CTX *ctx, SSL_SESSION *));
 void SSL_CTX_sess_set_get_cb(SSL_CTX *ctx,
           SSL_SESSION (*get_session_cb)(SSL *, unsigned char *, int, int *));

 int (*SSL_CTX_sess_get_new_cb(SSL_CTX *ctx))(struct ssl_st *ssl, SSL_SESSION *sess);
 void (*SSL_CTX_sess_get_remove_cb(SSL_CTX *ctx))(struct ssl_ctx_st *ctx, SSL_SESSION *sess);
 SSL_SESSION *(*SSL_CTX_sess_get_get_cb(SSL_CTX *ctx))(struct ssl_st *ssl, unsigned char *data, int len, int *copy);

 int (*new_session_cb)(struct ssl_st *ssl, SSL_SESSION *sess);
 void (*remove_session_cb)(struct ssl_ctx_st *ctx, SSL_SESSION *sess);
 SSL_SESSION *(*get_session_cb)(struct ssl_st *ssl, unsigned char *data,
               int len, int *copy);

 

DESCRIPTION

SSL_CTX_sess_set_new_cb() sets the callback function, which is automatically called whenever a new session was negotiated.

SSL_CTX_sess_set_remove_cb() sets the callback function, which is automatically called whenever a session is removed by the SSL engine, because it is considered faulty or the session has become obsolete because of exceeding the timeout value.

SSL_CTX_sess_set_get_cb() sets the callback function which is called, whenever a SSL/TLS client proposed to resume a session but the session could not be found in the internal session cache (see SSL_CTX_set_session_cache_mode(3)). (SSL/TLS server only.)

SSL_CTX_sess_get_new_cb(), SSL_CTX_sess_get_remove_cb(), and SSL_CTX_sess_get_get_cb() allow to retrieve the function pointers of the provided callback functions. If a callback function has not been set, the NULL pointer is returned.  

NOTES

In order to allow external session caching, synchronization with the internal session cache is realized via callback functions. Inside these callback functions, session can be saved to disk or put into a database using the d2i_SSL_SESSION(3) interface.

The new_session_cb() is called, whenever a new session has been negotiated and session caching is enabled (see SSL_CTX_set_session_cache_mode(3)). The new_session_cb() is passed the ssl connection and the ssl session sess. If the callback returns 0, the session will be immediately removed again.

The remove_session_cb() is called, whenever the SSL engine removes a session from the internal cache. This happens when the session is removed because it is expired or when a connection was not shutdown cleanly. It also happens for all sessions in the internal session cache when SSL_CTX_free(3) is called. The remove_session_cb() is passed the ctx and the ssl session sess. It does not provide any feedback.

The get_session_cb() is only called on SSL/TLS servers with the session id proposed by the client. The get_session_cb() is always called, also when session caching was disabled. The get_session_cb() is passed the ssl connection, the session id of length length at the memory location data. With the parameter copy the callback can require the SSL engine to increment the reference count of the SSL_SESSION object, Normally the reference count is not incremented and therefore the session must not be explicitly freed with SSL_SESSION_free(3).  

SEE ALSO

ssl(3), d2i_SSL_SESSION(3), SSL_CTX_set_session_cache_mode(3), SSL_CTX_flush_sessions(3), SSL_SESSION_free(3), SSL_CTX_free(3)


 

Index

NAME
SYNOPSIS
DESCRIPTION
NOTES
SEE ALSO


Please read "Why adblockers are bad".



Other free services
toURL.org
Shorten long
URLs to short
links like
http://tourl.org/2
tourl.org
.
Reverse DNS lookup
Find out which hostname(s)
resolve to a
given IP or other hostnames for the server
www.reversednslookup.org
rdf newsfeed | rss newsfeed | Atom newsfeed
- Powered by LeopardCMS - Running on Gentoo -
Copyright 2004-2017 Sascha Nitsch Unternehmensberatung UG(haftungsbeschränkt)
Valid XHTML1.1 : Valid CSS : buttonmaker
- Level Triple-A Conformance to Web Content Accessibility Guidelines 1.0 -
- Copyright and legal notices -
Time to create this page: 18.8 ms