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 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.