=pod

=head1 NAME

BIO_get_ex_new_index, BIO_set_ex_data, BIO_get_ex_data,
BIO_set_app_data, BIO_get_app_data,
DH_get_ex_new_index, DH_set_ex_data, DH_get_ex_data,
DSA_get_ex_new_index, DSA_set_ex_data, DSA_get_ex_data,
EC_KEY_get_ex_new_index, EC_KEY_set_ex_data, EC_KEY_get_ex_data,
EVP_PKEY_get_ex_new_index, EVP_PKEY_set_ex_data, EVP_PKEY_get_ex_data,
RSA_get_ex_new_index, RSA_set_ex_data, RSA_get_ex_data,
RSA_set_app_data, RSA_get_app_data,
SSL_get_ex_new_index, SSL_set_ex_data, SSL_get_ex_data,
SSL_set_app_data, SSL_get_app_data,
SSL_CTX_get_ex_new_index, SSL_CTX_set_ex_data, SSL_CTX_get_ex_data,
SSL_CTX_set_app_data, SSL_CTX_get_app_data,
SSL_SESSION_get_ex_new_index, SSL_SESSION_set_ex_data, SSL_SESSION_get_ex_data,
SSL_SESSION_set_app_data, SSL_SESSION_get_app_data,
UI_get_ex_new_index, UI_set_ex_data, UI_get_ex_data,
UI_set_app_data, UI_get_app_data,
X509_STORE_CTX_get_ex_new_index, X509_STORE_CTX_set_ex_data, X509_STORE_CTX_get_ex_data,
X509_STORE_CTX_set_app_data, X509_STORE_CTX_get_app_data,
X509_STORE_get_ex_new_index, X509_STORE_set_ex_data, X509_STORE_get_ex_data,
X509_get_ex_new_index, X509_set_ex_data, X509_get_ex_data
- application-specific data

=head1 SYNOPSIS

=for openssl generic

 #include <openssl/x509.h>

 int TYPE_get_ex_new_index(long argl, void *argp,
                           CRYPTO_EX_new *new_func,
                           CRYPTO_EX_dup *dup_func,
                           CRYPTO_EX_free *free_func);

 int TYPE_set_ex_data(TYPE *d, int idx, void *arg);

 void *TYPE_get_ex_data(const TYPE *d, int idx);

 #define TYPE_set_app_data(TYPE *d, void *arg)
 #define TYPE_get_app_data(TYPE *d)

The following functions have been deprecated since OpenSSL 3.0, and can be
hidden entirely by defining B<OPENSSL_API_COMPAT> with a suitable version value,
see L<openssl_user_macros(7)>:

 int DH_get_ex_new_index(long argl, void *argp, CRYPTO_EX_new *new_func,
                         CRYPTO_EX_dup *dup_func, CRYPTO_EX_free *free_func);
 int DH_set_ex_data(DH *type, int idx, void *arg);
 void *DH_get_ex_data(DH *type, int idx);
 int DSA_get_ex_new_index(long argl, void *argp, CRYPTO_EX_new *new_func,
                          CRYPTO_EX_dup *dup_func, CRYPTO_EX_free *free_func);
 int DSA_set_ex_data(DSA *type, int idx, void *arg);
 void *DSA_get_ex_data(DSA *type, int idx);
 int EC_KEY_get_ex_new_index(long argl, void *argp, CRYPTO_EX_new *new_func,
                             CRYPTO_EX_dup *dup_func, CRYPTO_EX_free *free_func);
 int EC_KEY_set_ex_data(EC_KEY *type, int idx, void *arg);
 void *EC_KEY_get_ex_data(EC_KEY *type, int idx);
 int RSA_get_ex_new_index(long argl, void *argp, CRYPTO_EX_new *new_func,
                          CRYPTO_EX_dup *dup_func, CRYPTO_EX_free *free_func);
 int RSA_set_ex_data(RSA *type, int idx, void *arg);
 void *RSA_get_ex_data(RSA *type, int idx);
 int RSA_set_app_data(RSA *type, void *arg);
 void *RSA_get_app_data(RSA *type);

=head1 DESCRIPTION

In the description here, I<TYPE> is used a placeholder
for any of the OpenSSL datatypes listed in L<CRYPTO_get_ex_new_index(3)>.

All functions with a I<TYPE> of B<DH>, B<DSA>, B<RSA> and B<EC_KEY> are deprecated.
Applications should instead use EVP_PKEY_set_ex_data(),
EVP_PKEY_get_ex_data() and EVP_PKEY_get_ex_new_index().

These functions handle application-specific data for OpenSSL data
structures.

TYPE_get_ex_new_index() is a macro that calls CRYPTO_get_ex_new_index()
with the correct B<index> value.

TYPE_set_ex_data() is a function that calls CRYPTO_set_ex_data() with
an offset into the opaque exdata part of the TYPE object. I<d> B<MUST NOT> be NULL.

TYPE_get_ex_data() is a function that calls CRYPTO_get_ex_data() with
an offset into the opaque exdata part of the TYPE object. I<d> B<MUST NOT> be NULL.

For compatibility with previous releases, the exdata index of zero is
reserved for "application data." There are two convenience functions for
this.
TYPE_set_app_data() is a macro that invokes TYPE_set_ex_data() with
B<idx> set to zero.
TYPE_get_app_data() is a macro that invokes TYPE_get_ex_data() with
B<idx> set to zero.

=head1 RETURN VALUES

TYPE_get_ex_new_index() returns a new index on success or -1 on error.

TYPE_set_ex_data() returns 1 on success or 0 on error.

TYPE_get_ex_data() returns the application data or NULL if an error occurred.

=head1 SEE ALSO

L<CRYPTO_get_ex_new_index(3)>.

=head1 HISTORY

The functions DH_get_ex_new_index(), DH_set_ex_data(), DH_get_ex_data(),
DSA_get_ex_new_index(), DSA_set_ex_data(), DSA_get_ex_data(),
EC_KEY_get_ex_new_index(), EC_KEY_set_ex_data(), EC_KEY_get_ex_data(),
RSA_get_ex_new_index(), RSA_set_ex_data(), RSA_get_ex_data(),
RSA_set_app_data() and RSA_get_app_data() were deprecated in OpenSSL 3.0.

=head1 COPYRIGHT

Copyright 2015-2025 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
