xref: /freebsd/crypto/openssl/doc/man3/SSL_set_shutdown.pod (revision dd41de95a84d979615a2ef11df6850622bf6184e)
1=pod
2
3=head1 NAME
4
5SSL_set_shutdown, SSL_get_shutdown - manipulate shutdown state of an SSL connection
6
7=head1 SYNOPSIS
8
9 #include <openssl/ssl.h>
10
11 void SSL_set_shutdown(SSL *ssl, int mode);
12
13 int SSL_get_shutdown(const SSL *ssl);
14
15=head1 DESCRIPTION
16
17SSL_set_shutdown() sets the shutdown state of B<ssl> to B<mode>.
18
19SSL_get_shutdown() returns the shutdown mode of B<ssl>.
20
21=head1 NOTES
22
23The shutdown state of an ssl connection is a bit mask of:
24
25=over 4
26
27=item Z<>0
28
29No shutdown setting, yet.
30
31=item SSL_SENT_SHUTDOWN
32
33A close_notify shutdown alert was sent to the peer, the connection is being
34considered closed and the session is closed and correct.
35
36=item SSL_RECEIVED_SHUTDOWN
37
38A shutdown alert was received form the peer, either a normal close_notify
39or a fatal error.
40
41=back
42
43SSL_SENT_SHUTDOWN and SSL_RECEIVED_SHUTDOWN can be set at the same time.
44
45The shutdown state of the connection is used to determine the state of
46the ssl session. If the session is still open, when
47L<SSL_clear(3)> or L<SSL_free(3)> is called,
48it is considered bad and removed according to RFC2246.
49The actual condition for a correctly closed session is SSL_SENT_SHUTDOWN
50(according to the TLS RFC, it is acceptable to only send the close_notify
51alert but to not wait for the peer's answer, when the underlying connection
52is closed).
53SSL_set_shutdown() can be used to set this state without sending a
54close alert to the peer (see L<SSL_shutdown(3)>).
55
56If a close_notify was received, SSL_RECEIVED_SHUTDOWN will be set,
57for setting SSL_SENT_SHUTDOWN the application must however still call
58L<SSL_shutdown(3)> or SSL_set_shutdown() itself.
59
60=head1 RETURN VALUES
61
62SSL_set_shutdown() does not return diagnostic information.
63
64SSL_get_shutdown() returns the current setting.
65
66=head1 SEE ALSO
67
68L<ssl(7)>, L<SSL_shutdown(3)>,
69L<SSL_CTX_set_quiet_shutdown(3)>,
70L<SSL_clear(3)>, L<SSL_free(3)>
71
72=head1 COPYRIGHT
73
74Copyright 2001-2020 The OpenSSL Project Authors. All Rights Reserved.
75
76Licensed under the OpenSSL license (the "License").  You may not use
77this file except in compliance with the License.  You can obtain a copy
78in the file LICENSE in the source distribution or at
79L<https://www.openssl.org/source/license.html>.
80
81=cut
82