| =pod |
| |
| =head1 NAME |
| |
| SSL_want, SSL_want_nothing, SSL_want_read, SSL_want_write, |
| SSL_want_x509_lookup, SSL_want_retry_verify, SSL_want_async, SSL_want_async_job, |
| SSL_want_client_hello_cb - obtain state information TLS/SSL I/O operation |
| |
| =head1 SYNOPSIS |
| |
| #include <openssl/ssl.h> |
| |
| int SSL_want(const SSL *ssl); |
| int SSL_want_nothing(const SSL *ssl); |
| int SSL_want_read(const SSL *ssl); |
| int SSL_want_write(const SSL *ssl); |
| int SSL_want_x509_lookup(const SSL *ssl); |
| int SSL_want_retry_verify(const SSL *ssl); |
| int SSL_want_async(const SSL *ssl); |
| int SSL_want_async_job(const SSL *ssl); |
| int SSL_want_client_hello_cb(const SSL *ssl); |
| |
| =head1 DESCRIPTION |
| |
| SSL_want() returns state information for the SSL object B<ssl>. |
| |
| The other SSL_want_*() calls are shortcuts for the possible states returned |
| by SSL_want(). |
| |
| =head1 NOTES |
| |
| SSL_want() examines the internal state information of the SSL object. Its |
| return values are similar to that of L<SSL_get_error(3)>. |
| Unlike L<SSL_get_error(3)>, which also evaluates the |
| error queue, the results are obtained by examining an internal state flag |
| only. The information must therefore only be used for normal operation under |
| nonblocking I/O. Error conditions are not handled and must be treated |
| using L<SSL_get_error(3)>. |
| |
| The result returned by SSL_want() should always be consistent with |
| the result of L<SSL_get_error(3)>. |
| |
| =head1 RETURN VALUES |
| |
| The following return values can currently occur for SSL_want(): |
| |
| =over 4 |
| |
| =item SSL_NOTHING |
| |
| There is no data to be written or to be read. |
| |
| =item SSL_WRITING |
| |
| There are data in the SSL buffer that must be written to the underlying |
| B<BIO> layer in order to complete the actual SSL_*() operation. |
| A call to L<SSL_get_error(3)> should return B<SSL_ERROR_WANT_WRITE>. |
| |
| =item SSL_READING |
| |
| More data must be read from the underlying B<BIO> layer in order to |
| complete the actual SSL_*() operation. |
| A call to L<SSL_get_error(3)> should return B<SSL_ERROR_WANT_READ>. |
| |
| =item SSL_X509_LOOKUP |
| |
| The operation did not complete because an application callback set by |
| SSL_CTX_set_client_cert_cb() has asked to be called again. |
| A call to L<SSL_get_error(3)> should return B<SSL_ERROR_WANT_X509_LOOKUP>. |
| |
| =item SSL_RETRY_VERIFY |
| |
| The operation did not complete because a certificate verification callback |
| has asked to be called again via L<SSL_set_retry_verify(3)>. |
| A call to L<SSL_get_error(3)> should return B<SSL_ERROR_WANT_RETRY_VERIFY>. |
| |
| =item SSL_ASYNC_PAUSED |
| |
| An asynchronous operation partially completed and was then paused. See |
| L<SSL_get_all_async_fds(3)>. A call to L<SSL_get_error(3)> should return |
| B<SSL_ERROR_WANT_ASYNC>. |
| |
| =item SSL_ASYNC_NO_JOBS |
| |
| The asynchronous job could not be started because there were no async jobs |
| available in the pool (see ASYNC_init_thread(3)). A call to L<SSL_get_error(3)> |
| should return B<SSL_ERROR_WANT_ASYNC_JOB>. |
| |
| =item SSL_CLIENT_HELLO_CB |
| |
| The operation did not complete because an application callback set by |
| SSL_CTX_set_client_hello_cb() has asked to be called again. |
| A call to L<SSL_get_error(3)> should return B<SSL_ERROR_WANT_CLIENT_HELLO_CB>. |
| |
| =back |
| |
| SSL_want_nothing(), SSL_want_read(), SSL_want_write(), |
| SSL_want_x509_lookup(), SSL_want_retry_verify(), |
| SSL_want_async(), SSL_want_async_job(), and SSL_want_client_hello_cb() |
| return 1 when the corresponding condition is true or 0 otherwise. |
| |
| =head1 SEE ALSO |
| |
| L<ssl(7)>, L<SSL_get_error(3)> |
| |
| =head1 HISTORY |
| |
| The SSL_want_client_hello_cb() function and the SSL_CLIENT_HELLO_CB return value |
| were added in OpenSSL 1.1.1. |
| |
| =head1 COPYRIGHT |
| |
| Copyright 2001-2022 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 |
