Update pre9
This commit is contained in:
@@ -145,13 +145,39 @@ DTLS connections.
|
||||
|
||||
=item SSL_OP_NO_TICKET
|
||||
|
||||
Normally clients and servers will, where possible, transparently make use
|
||||
of RFC4507bis tickets for stateless session resumption.
|
||||
SSL/TLS supports two mechanisms for resuming sessions: session ids and stateless
|
||||
session tickets.
|
||||
|
||||
If this option is set this functionality is disabled and tickets will
|
||||
not be used by clients or servers.
|
||||
When using session ids a copy of the session information is
|
||||
cached on the server and a unique id is sent to the client. When the client
|
||||
wishes to resume it provides the unique id so that the server can retrieve the
|
||||
session information from its cache.
|
||||
|
||||
This option only applies to TLSv1.2 and below. It is ignored for TLSv1.3.
|
||||
When using stateless session tickets the server uses a session ticket encryption
|
||||
key to encrypt the session information. This encrypted data is sent to the
|
||||
client as a "ticket". When the client wishes to resume it sends the encrypted
|
||||
data back to the server. The server uses its key to decrypt the data and resume
|
||||
the session. In this way the server can operate statelessly - no session
|
||||
information needs to be cached locally.
|
||||
|
||||
The TLSv1.3 protocol only supports tickets and does not directly support session
|
||||
ids. However OpenSSL allows two modes of ticket operation in TLSv1.3: stateful
|
||||
and stateless. Stateless tickets work the same way as in TLSv1.2 and below.
|
||||
Stateful tickets mimic the session id behaviour available in TLSv1.2 and below.
|
||||
The session information is cached on the server and the session id is wrapped up
|
||||
in a ticket and sent back to the client. When the client wishes to resume, it
|
||||
presents a ticket in the same way as for stateless tickets. The server can then
|
||||
extract the session id from the ticket and retrieve the session information from
|
||||
its cache.
|
||||
|
||||
By default OpenSSL will use stateless tickets. The SSL_OP_NO_TICKET option will
|
||||
cause stateless tickets to not be issued. In TLSv1.2 and below this means no
|
||||
ticket gets sent to the client at all. In TLSv1.3 a stateful ticket will be
|
||||
sent. This is a server-side option only.
|
||||
|
||||
In TLSv1.3 it is possible to suppress all tickets (stateful and stateless) from
|
||||
being sent by calling L<SSL_CTX_set_num_tickets(3)> or
|
||||
L<SSL_set_num_tickets(3)>.
|
||||
|
||||
=item SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION
|
||||
|
||||
|
||||
Reference in New Issue
Block a user