mirror of
https://github.com/openssl/openssl.git
synced 2024-12-15 06:01:37 +08:00
0f84cbc3e2
Reviewed-by: Tomas Mraz <tmraz@fedoraproject.org> (Merged from https://github.com/openssl/openssl/pull/12595)
167 lines
5.1 KiB
Plaintext
167 lines
5.1 KiB
Plaintext
=pod
|
|
|
|
=head1 NAME
|
|
|
|
SSL_CTX_set_info_callback,
|
|
SSL_CTX_get_info_callback,
|
|
SSL_set_info_callback,
|
|
SSL_get_info_callback
|
|
- handle information callback for SSL connections
|
|
|
|
=head1 SYNOPSIS
|
|
|
|
#include <openssl/ssl.h>
|
|
|
|
void SSL_CTX_set_info_callback(SSL_CTX *ctx, void (*callback)());
|
|
void (*SSL_CTX_get_info_callback(const SSL_CTX *ctx))();
|
|
|
|
void SSL_set_info_callback(SSL *ssl, void (*callback)());
|
|
void (*SSL_get_info_callback(const SSL *ssl))();
|
|
|
|
=head1 DESCRIPTION
|
|
|
|
SSL_CTX_set_info_callback() sets the B<callback> function, that can be used to
|
|
obtain state information for SSL objects created from B<ctx> during connection
|
|
setup and use. The setting for B<ctx> is overridden from the setting for
|
|
a specific SSL object, if specified.
|
|
When B<callback> is NULL, no callback function is used.
|
|
|
|
SSL_set_info_callback() sets the B<callback> function, that can be used to
|
|
obtain state information for B<ssl> during connection setup and use.
|
|
When B<callback> is NULL, the callback setting currently valid for
|
|
B<ctx> is used.
|
|
|
|
SSL_CTX_get_info_callback() returns a pointer to the currently set information
|
|
callback function for B<ctx>.
|
|
|
|
SSL_get_info_callback() returns a pointer to the currently set information
|
|
callback function for B<ssl>.
|
|
|
|
=head1 NOTES
|
|
|
|
When setting up a connection and during use, it is possible to obtain state
|
|
information from the SSL/TLS engine. When set, an information callback function
|
|
is called whenever a significant event occurs such as: the state changes,
|
|
an alert appears, or an error occurs.
|
|
|
|
The callback function is called as B<callback(SSL *ssl, int where, int ret)>.
|
|
The B<where> argument specifies information about where (in which context)
|
|
the callback function was called. If B<ret> is 0, an error condition occurred.
|
|
If an alert is handled, SSL_CB_ALERT is set and B<ret> specifies the alert
|
|
information.
|
|
|
|
B<where> is a bit-mask made up of the following bits:
|
|
|
|
=over 4
|
|
|
|
=item SSL_CB_LOOP
|
|
|
|
Callback has been called to indicate state change or some other significant
|
|
state machine event. This may mean that the callback gets invoked more than once
|
|
per state in some situations.
|
|
|
|
=item SSL_CB_EXIT
|
|
|
|
Callback has been called to indicate exit of a handshake function. This will
|
|
happen after the end of a handshake, but may happen at other times too such as
|
|
on error or when IO might otherwise block and nonblocking is being used.
|
|
|
|
=item SSL_CB_READ
|
|
|
|
Callback has been called during read operation.
|
|
|
|
=item SSL_CB_WRITE
|
|
|
|
Callback has been called during write operation.
|
|
|
|
=item SSL_CB_ALERT
|
|
|
|
Callback has been called due to an alert being sent or received.
|
|
|
|
=item SSL_CB_READ_ALERT (SSL_CB_ALERT|SSL_CB_READ)
|
|
|
|
=item SSL_CB_WRITE_ALERT (SSL_CB_ALERT|SSL_CB_WRITE)
|
|
|
|
=item SSL_CB_ACCEPT_LOOP (SSL_ST_ACCEPT|SSL_CB_LOOP)
|
|
|
|
=item SSL_CB_ACCEPT_EXIT (SSL_ST_ACCEPT|SSL_CB_EXIT)
|
|
|
|
=item SSL_CB_CONNECT_LOOP (SSL_ST_CONNECT|SSL_CB_LOOP)
|
|
|
|
=item SSL_CB_CONNECT_EXIT (SSL_ST_CONNECT|SSL_CB_EXIT)
|
|
|
|
=item SSL_CB_HANDSHAKE_START
|
|
|
|
Callback has been called because a new handshake is started. It also occurs when
|
|
resuming a handshake following a pause to handle early data.
|
|
|
|
=item SSL_CB_HANDSHAKE_DONE
|
|
|
|
Callback has been called because a handshake is finished. It also occurs if the
|
|
handshake is paused to allow the exchange of early data.
|
|
|
|
=back
|
|
|
|
The current state information can be obtained using the
|
|
L<SSL_state_string(3)> family of functions.
|
|
|
|
The B<ret> information can be evaluated using the
|
|
L<SSL_alert_type_string(3)> family of functions.
|
|
|
|
=head1 RETURN VALUES
|
|
|
|
SSL_set_info_callback() does not provide diagnostic information.
|
|
|
|
SSL_get_info_callback() returns the current setting.
|
|
|
|
=head1 EXAMPLES
|
|
|
|
The following example callback function prints state strings, information
|
|
about alerts being handled and error messages to the B<bio_err> BIO.
|
|
|
|
void apps_ssl_info_callback(SSL *s, int where, int ret)
|
|
{
|
|
const char *str;
|
|
int w = where & ~SSL_ST_MASK;
|
|
|
|
if (w & SSL_ST_CONNECT)
|
|
str = "SSL_connect";
|
|
else if (w & SSL_ST_ACCEPT)
|
|
str = "SSL_accept";
|
|
else
|
|
str = "undefined";
|
|
|
|
if (where & SSL_CB_LOOP) {
|
|
BIO_printf(bio_err, "%s:%s\n", str, SSL_state_string_long(s));
|
|
} else if (where & SSL_CB_ALERT) {
|
|
str = (where & SSL_CB_READ) ? "read" : "write";
|
|
BIO_printf(bio_err, "SSL3 alert %s:%s:%s\n", str,
|
|
SSL_alert_type_string_long(ret),
|
|
SSL_alert_desc_string_long(ret));
|
|
} else if (where & SSL_CB_EXIT) {
|
|
if (ret == 0) {
|
|
BIO_printf(bio_err, "%s:failed in %s\n",
|
|
str, SSL_state_string_long(s));
|
|
} else if (ret < 0) {
|
|
BIO_printf(bio_err, "%s:error in %s\n",
|
|
str, SSL_state_string_long(s));
|
|
}
|
|
}
|
|
}
|
|
|
|
=head1 SEE ALSO
|
|
|
|
L<ssl(7)>, L<SSL_state_string(3)>,
|
|
L<SSL_alert_type_string(3)>
|
|
|
|
=head1 COPYRIGHT
|
|
|
|
Copyright 2001-2020 The OpenSSL Project Authors. All Rights Reserved.
|
|
|
|
Licensed under the Apache License 2.0 (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
|