Openssl 1.1.0h

doc/ssl/SSL_CTX_set_psk_client_callback.pod

@@ -0,0 +1,63 @@
+=pod
+
+=head1 NAME
+
+SSL_CTX_set_psk_client_callback, SSL_set_psk_client_callback - set PSK client callback
+
+=head1 SYNOPSIS
+
+ #include <openssl/ssl.h>
+
+ void SSL_CTX_set_psk_client_callback(SSL_CTX *ctx,
+        unsigned int (*callback)(SSL *ssl, const char *hint,
+        char *identity, unsigned int max_identity_len,
+        unsigned char *psk, unsigned int max_psk_len));
+ void SSL_set_psk_client_callback(SSL *ssl,
+        unsigned int (*callback)(SSL *ssl, const char *hint,
+        char *identity, unsigned int max_identity_len,
+        unsigned char *psk, unsigned int max_psk_len));
+
+
+=head1 DESCRIPTION
+
+A client application must provide a callback function which is called
+when the client is sending the ClientKeyExchange message to the server.
+
+The purpose of the callback function is to select the PSK identity and
+the pre-shared key to use during the connection setup phase.
+
+The callback is set using functions SSL_CTX_set_psk_client_callback()
+or SSL_set_psk_client_callback(). The callback function is given the
+connection in parameter B<ssl>, a B<NULL>-terminated PSK identity hint
+sent by the server in parameter B<hint>, a buffer B<identity> of
+length B<max_identity_len> bytes where the resulting
+B<NULL>-terminated identity is to be stored, and a buffer B<psk> of
+length B<max_psk_len> bytes where the resulting pre-shared key is to
+be stored.
+
+=head1 NOTES
+
+Note that parameter B<hint> given to the callback may be B<NULL>.
+
+=head1 RETURN VALUES
+
+Return values from the client callback are interpreted as follows:
+
+On success (callback found a PSK identity and a pre-shared key to use)
+the length (> 0) of B<psk> in bytes is returned.
+
+Otherwise or on errors callback should return 0. In this case
+the connection setup fails.
+
+=head1 COPYRIGHT
+
+Copyright 2006-2016 The OpenSSL Project Authors. All Rights Reserved.
+
+Licensed under the OpenSSL license (the "License").  You may not use
+this file except in compliance with the License.  You can obtain a copy
+in the file LICENSE in the source distribution or at
+L<https://www.openssl.org/source/license.html>.
+
+Copyright 2005 Nokia.
+
+=cut