xref: /openbsd/lib/libssl/man/SSL_set_shutdown.3 (revision d415bd75)
1.\"	$OpenBSD: SSL_set_shutdown.3,v 1.6 2021/06/11 19:41:39 jmc Exp $
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51.Dd $Mdocdate: June 11 2021 $
52.Dt SSL_SET_SHUTDOWN 3
53.Os
54.Sh NAME
55.Nm SSL_set_shutdown ,
56.Nm SSL_get_shutdown
57.Nd manipulate shutdown state of an SSL connection
58.Sh SYNOPSIS
59.In openssl/ssl.h
60.Ft void
61.Fn SSL_set_shutdown "SSL *ssl" "int mode"
62.Ft int
63.Fn SSL_get_shutdown "const SSL *ssl"
64.Sh DESCRIPTION
65.Fn SSL_set_shutdown
66sets the shutdown state of
67.Fa ssl
68to
69.Fa mode .
70.Pp
71.Fn SSL_get_shutdown
72returns the shutdown mode of
73.Fa ssl .
74.Pp
75The shutdown state of an ssl connection is a bitmask of:
76.Bl -tag -width Ds
77.It 0
78No shutdown setting, yet.
79.It Dv SSL_SENT_SHUTDOWN
80A
81.Dq close notify
82shutdown alert was sent to the peer; the connection is being considered closed
83and the session is closed and correct.
84.It Dv SSL_RECEIVED_SHUTDOWN
85A shutdown alert was received form the peer, either a normal
86.Dq close notify
87or a fatal error.
88.El
89.Pp
90.Dv SSL_SENT_SHUTDOWN
91and
92.Dv SSL_RECEIVED_SHUTDOWN
93can be set at the same time.
94.Pp
95The shutdown state of the connection is used to determine the state of the
96.Fa ssl
97session.
98If the session is still open when
99.Xr SSL_clear 3
100or
101.Xr SSL_free 3
102is called, it is considered bad and removed according to RFC 2246.
103The actual condition for a correctly closed session is
104.Dv SSL_SENT_SHUTDOWN
105(according to the TLS RFC, it is acceptable to only send the
106.Dq close notify
107alert but to not wait for the peer's answer when the underlying connection is
108closed).
109.Fn SSL_set_shutdown
110can be used to set this state without sending a close alert to the peer (see
111.Xr SSL_shutdown 3 ) .
112.Pp
113If a
114.Dq close notify
115was received,
116.Dv SSL_RECEIVED_SHUTDOWN
117will be set, but to set
118.Dv SSL_SENT_SHUTDOWN
119the application must still call
120.Xr SSL_shutdown 3
121or
122.Fn SSL_set_shutdown
123itself.
124.Sh RETURN VALUES
125.Fn SSL_get_shutdown
126returns the current setting.
127.Sh SEE ALSO
128.Xr ssl 3 ,
129.Xr SSL_clear 3 ,
130.Xr SSL_CTX_set_quiet_shutdown 3 ,
131.Xr SSL_free 3 ,
132.Xr SSL_shutdown 3
133.Sh HISTORY
134.Fn SSL_set_shutdown
135and
136.Fn SSL_get_shutdown
137first appeared in SSLeay 0.8.0 and have been available since
138.Ox 2.4 .
139