mirror of
https://github.com/openssl/openssl.git
synced 2024-12-09 05:51:54 +08:00
e105ae842f
Reviewed-by: Ben Kaduk <kaduk@mit.edu> (Merged from https://github.com/openssl/openssl/pull/3926)
138 lines
5.1 KiB
Plaintext
138 lines
5.1 KiB
Plaintext
=pod
|
|
|
|
=head1 NAME
|
|
|
|
SSL_psk_server_cb_func,
|
|
SSL_psk_find_session_cb_func,
|
|
SSL_CTX_use_psk_identity_hint,
|
|
SSL_use_psk_identity_hint,
|
|
SSL_CTX_set_psk_server_callback,
|
|
SSL_set_psk_server_callback,
|
|
SSL_CTX_set_psk_find_session_callback,
|
|
SSL_set_psk_find_session_callback
|
|
- set PSK identity hint to use
|
|
|
|
=head1 SYNOPSIS
|
|
|
|
#include <openssl/ssl.h>
|
|
|
|
typedef unsigned int (*SSL_psk_server_cb_func)(SSL *ssl,
|
|
const char *identity,
|
|
unsigned char *psk,
|
|
unsigned int max_psk_len);
|
|
|
|
typedef int (*SSL_psk_find_session_cb_func)(SSL *ssl,
|
|
const unsigned char *identity,
|
|
size_t identity_len,
|
|
SSL_SESSION **sess);
|
|
|
|
int SSL_CTX_use_psk_identity_hint(SSL_CTX *ctx, const char *hint);
|
|
int SSL_use_psk_identity_hint(SSL *ssl, const char *hint);
|
|
|
|
void SSL_CTX_set_psk_server_callback(SSL_CTX *ctx, SSL_psk_server_cb_func cb);
|
|
void SSL_set_psk_server_callback(SSL *ssl, SSL_psk_server_cb_func cb);
|
|
|
|
void SSL_CTX_set_psk_find_session_callback(SSL_CTX *ctx,
|
|
SSL_psk_find_session_cb_func cb);
|
|
void SSL_set_psk_find_session_callback(SSL *s, SSL_psk_find_session_cb_func cb);
|
|
|
|
=head1 DESCRIPTION
|
|
|
|
TLSv1.3 Pre-Shared Keys (PSKs) and PSKs for TLSv1.2 and below are not
|
|
compatible.
|
|
|
|
Identity hints are not relevant for TLSv1.3. A server application wishing to use
|
|
PSK ciphersuites for TLSv1.2 and below may call SSL_CTX_use_psk_identity_hint()
|
|
to set the given B<NUL>-terminated PSK identity hint B<hint> for SSL context
|
|
object B<ctx>. SSL_use_psk_identity_hint() sets the given B<NUL>-terminated PSK
|
|
identity hint B<hint> for the SSL connection object B<ssl>. If B<hint> is
|
|
B<NULL> the current hint from B<ctx> or B<ssl> is deleted.
|
|
|
|
In the case where PSK identity hint is B<NULL>, the server does not send the
|
|
ServerKeyExchange message to the client.
|
|
|
|
A server application for TLSv1.2 and below must provide a callback function
|
|
which is called when the server receives the ClientKeyExchange message from the
|
|
client. The purpose of the callback function is to validate the
|
|
received PSK identity and to fetch the pre-shared key used during the
|
|
connection setup phase. The callback is set using the functions
|
|
SSL_CTX_set_psk_server_callback() or SSL_set_psk_server_callback(). The callback
|
|
function is given the connection in parameter B<ssl>, B<NUL>-terminated PSK
|
|
identity sent by the client in parameter B<identity>, and a buffer B<psk> of
|
|
length B<max_psk_len> bytes where the pre-shared key is to be stored.
|
|
|
|
A client application wishing to use TLSv1.3 PSKs must set a different callback
|
|
using either SSL_CTX_set_psk_use_session_callback() or
|
|
SSL_set_psk_use_session_callback() as appropriate.
|
|
|
|
The callback function is given a pointer to the SSL connection in B<ssl> and
|
|
an identity in B<identity> of length B<identity_len>. The callback function
|
|
should identify an SSL_SESSION object that provides the PSK details and store it
|
|
in B<*sess>. The SSL_SESSION object should, as a minimum, set the master key,
|
|
the ciphersuite and the protocol version. See
|
|
L<SSL_CTX_set_psk_use_session_callback(3)> for details.
|
|
|
|
It is also possible for the callback to succeed but not supply a PSK. In this
|
|
case no PSK will be used but the handshake will continue. To do this the
|
|
callback should return successfully and ensure that B<*sess> is
|
|
NULL.
|
|
|
|
=head1 NOTES
|
|
|
|
A connection established via a TLSv1.3 PSK will appear as if session resumption
|
|
has occurred so that L<SSL_session_reused(3)> will return true.
|
|
|
|
=head1 RETURN VALUES
|
|
|
|
B<SSL_CTX_use_psk_identity_hint()> and B<SSL_use_psk_identity_hint()> return
|
|
1 on success, 0 otherwise.
|
|
|
|
Return values from the TLSv1.2 and below server callback are interpreted as
|
|
follows:
|
|
|
|
=over 4
|
|
|
|
=item Z<>0
|
|
|
|
PSK identity was not found. An "unknown_psk_identity" alert message
|
|
will be sent and the connection setup fails.
|
|
|
|
=item E<gt>0
|
|
|
|
PSK identity was found and the server callback has provided the PSK
|
|
successfully in parameter B<psk>. Return value is the length of
|
|
B<psk> in bytes. It is an error to return a value greater than
|
|
B<max_psk_len>.
|
|
|
|
If the PSK identity was not found but the callback instructs the
|
|
protocol to continue anyway, the callback must provide some random
|
|
data to B<psk> and return the length of the random data, so the
|
|
connection will fail with decryption_error before it will be finished
|
|
completely.
|
|
|
|
=back
|
|
|
|
The B<SSL_psk_find_session_cb_func> callback should return 1 on success or 0 on
|
|
failure. In the event of failure the connection setup fails.
|
|
|
|
=head1 SEE ALSO
|
|
|
|
L<SSL_CTX_set_psk_use_session_callback(3)>,
|
|
L<SSL_set_psk_use_session_callback(3)>
|
|
|
|
=head1 HISTORY
|
|
|
|
SSL_CTX_set_psk_find_session_callback() and SSL_set_psk_find_session_callback()
|
|
were added in OpenSSL 1.1.1.
|
|
|
|
=head1 COPYRIGHT
|
|
|
|
Copyright 2006-2017 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>.
|
|
|
|
=cut
|