Possibly copies session state from one connection to another, for use
in TLS session resumption. This is not normally needed, but may be
used when the same session needs to be used between different
endpoints, as is required by some protocols, such as FTP over TLS.
source should have already completed a handshake and, since TLS 1.3,
it should have been used to read data at least once. conn should not
have completed a handshake.
It is not possible to know whether a call to this function will
actually do anything. Because session resumption is normally used
only for performance benefit, the TLS backend might not implement
this function. Even if implemented, it may not actually succeed in
allowing conn to resume source's TLS session, because the server
may not have sent a session resumption token to source, or it may
refuse to accept the token from conn. There is no way to know
whether a call to this function is actually successful.
Using this function is not required to benefit from session
resumption. If the TLS backend supports session resumption, the
session will be resumed automatically if it is possible to do so
without weakening the privacy guarantees normally provided by TLS,
without need to call this function. For example, with TLS 1.3,
a session ticket will be automatically copied from any
GTlsClientConnection that has previously received session tickets
from the server, provided a ticket is available that has not
previously been used for session resumption, since session ticket
reuse would be a privacy weakness. Using this function causes the
ticket to be copied without regard for privacy considerations.
Possibly copies session state from one connection to another, for use in TLS session resumption. This is not normally needed, but may be used when the same session needs to be used between different endpoints, as is required by some protocols, such as FTP over TLS. source should have already completed a handshake and, since TLS 1.3, it should have been used to read data at least once. conn should not have completed a handshake.
It is not possible to know whether a call to this function will actually do anything. Because session resumption is normally used only for performance benefit, the TLS backend might not implement this function. Even if implemented, it may not actually succeed in allowing conn to resume source's TLS session, because the server may not have sent a session resumption token to source, or it may refuse to accept the token from conn. There is no way to know whether a call to this function is actually successful.
Using this function is not required to benefit from session resumption. If the TLS backend supports session resumption, the session will be resumed automatically if it is possible to do so without weakening the privacy guarantees normally provided by TLS, without need to call this function. For example, with TLS 1.3, a session ticket will be automatically copied from any GTlsClientConnection that has previously received session tickets from the server, provided a ticket is available that has not previously been used for session resumption, since session ticket reuse would be a privacy weakness. Using this function causes the ticket to be copied without regard for privacy considerations.