NAME
SSL_CTX_set_psk_client_callback,
SSL_set_psk_client_callback —
set PSK client callback
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));
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
ssl, a NULL-terminated PSK
identity hint sent by the server in parameter hint, a
buffer identity of length
max_identity_len bytes where the resulting
NULL-terminated identity is to be stored, and a
buffer psk of length max_psk_len
bytes where the resulting pre-shared key is to be stored.
NOTES
Note that parameter hint given to the
callback may be NULL.
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 psk in bytes is returned.
Otherwise or on errors callback should return 0. In this case the connection setup fails.