1nbd_get_tls_negotiated(3) LIBNBD nbd_get_tls_negotiated(3)
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6 nbd_get_tls_negotiated - find out if TLS was negotiated on a connection
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9 #include <libnbd.h>
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11 int nbd_get_tls_negotiated (struct nbd_handle *h);
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14 After connecting you may call this to find out if the connection is
15 using TLS.
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17 This is only really useful if you set the TLS request mode to
18 "LIBNBD_TLS_ALLOW" (see nbd_set_tls(3)), because in this mode we try to
19 use TLS but fall back to unencrypted if it was not available. This
20 function will tell you if TLS was negotiated or not.
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22 In "LIBNBD_TLS_REQUIRE" mode (the most secure) the connection would
23 have failed if TLS could not be negotiated, and in "LIBNBD_TLS_DISABLE"
24 mode TLS is not tried.
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27 This call returns a boolean value.
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30 On error "-1" is returned.
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32 Refer to "ERROR HANDLING" in libnbd(3) for how to get further details
33 of the error.
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36 The handle must be connected and finished handshaking with the server,
37 or shut down, otherwise this call will return an error.
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40 This function first appeared in libnbd 1.2.
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42 If you need to test if this function is available at compile time check
43 if the following macro is defined:
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45 #define LIBNBD_HAVE_NBD_GET_TLS_NEGOTIATED 1
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48 nbd_create(3), nbd_get_tls(3), nbd_set_tls(3), libnbd(3).
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51 Eric Blake
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53 Richard W.M. Jones
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56 Copyright (C) 2019 Red Hat Inc.
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59 This library is free software; you can redistribute it and/or modify it
60 under the terms of the GNU Lesser General Public License as published
61 by the Free Software Foundation; either version 2 of the License, or
62 (at your option) any later version.
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64 This library is distributed in the hope that it will be useful, but
65 WITHOUT ANY WARRANTY; without even the implied warranty of
66 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
67 Lesser General Public License for more details.
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69 You should have received a copy of the GNU Lesser General Public
70 License along with this library; if not, write to the Free Software
71 Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
72 02110-1301 USA
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76libnbd-1.3.7 2020-04-23 nbd_get_tls_negotiated(3)