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Editing: SSL_set_psk_client_callback.3
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Always turn off hyphenation; it makes .\" way too many mistakes in technical documents. .if n .ad l .nh .SH "NAME" SSL_CTX_set_psk_client_callback, SSL_set_psk_client_callback \- set PSK client callback .SH "SYNOPSIS" .IX Header "SYNOPSIS" .Vb 1 \& #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)); .Ve .SH "DESCRIPTION" .IX Header "DESCRIPTION" A client application must provide a callback function which is called when the client is sending the ClientKeyExchange message to the server. .PP The purpose of the callback function is to select the \s-1PSK\s0 identity and the pre-shared key to use during the connection setup phase. .PP The callback is set using functions \fBSSL_CTX_set_psk_client_callback()\fR or \fBSSL_set_psk_client_callback()\fR. The callback function is given the connection in parameter \fBssl\fR, a \fB\s-1NULL\s0\fR\-terminated \s-1PSK\s0 identity hint sent by the server in parameter \fBhint\fR, a buffer \fBidentity\fR of length \fBmax_identity_len\fR bytes where the the resulting \&\fB\s-1NULL\s0\fR\-terminated identity is to be stored, and a buffer \fBpsk\fR of length \fBmax_psk_len\fR bytes where the resulting pre-shared key is to be stored. .SH "NOTES" .IX Header "NOTES" Note that parameter \fBhint\fR given to the callback may be \fB\s-1NULL\s0\fR. .SH "RETURN VALUES" .IX Header "RETURN VALUES" Return values from the client callback are interpreted as follows: .PP On success (callback found a \s-1PSK\s0 identity and a pre-shared key to use) the length (> 0) of \fBpsk\fR in bytes is returned. .PP Otherwise or on errors callback should return 0. In this case the connection setup fails.
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