1 .\" $OpenBSD: SSL_get_session.3,v 1.2 2016/12/03 09:13:56 schwarze Exp $
2 .\" OpenSSL b97fdb57 Nov 11 09:33:09 2016 +0100
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52 .Dd $Mdocdate: December 3 2016 $
57 .Nm SSL_get0_session ,
59 .Nd retrieve TLS/SSL session data
63 .Fn SSL_get_session "const SSL *ssl"
65 .Fn SSL_get0_session "const SSL *ssl"
67 .Fn SSL_get1_session "SSL *ssl"
70 returns a pointer to the
74 The reference count of the
76 is not incremented, so that the pointer can become invalid by other operations.
85 but the reference count of the
87 is incremented by one.
91 session contains all information required to re-establish the connection
92 without a new handshake.
95 returns a pointer to the actual session.
96 As the reference counter is not incremented,
97 the pointer is only valid while the connection is in use.
102 is called, the session may be removed completely (if considered bad),
103 and the pointer obtained will become invalid.
104 Even if the session is valid,
105 it can be removed at any time due to timeout during
106 .Xr SSL_CTX_flush_sessions 3 .
108 If the data is to be kept,
110 will increment the reference count, so that the session will not be implicitly
111 removed by other operations but stays in memory.
112 In order to remove the session
113 .Xr SSL_SESSION_free 3
114 must be explicitly called once to decrement the reference count again.
117 objects keep internal link information about the session cache list when being
120 object's session cache.
123 object, regardless of its reference count, must therefore only be used with one
127 objects created from this
131 The following return values can occur:
134 There is no session available in
136 .It Pointer to an Vt SSL_SESSION
137 The return value points to the data of an
145 .Xr SSL_SESSION_free 3