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
#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);
SSL_want() returns state information for the SSL object
ssl.
The other SSL_want_*() calls are shortcuts for the possible states returned by
SSL_want().
SSL_want() examines the internal state information of the SSL object. Its
return values are similar to that of
SSL_get_error(3). Unlike
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
SSL_get_error(3).
The result returned by
SSL_want() should always be consistent with the
result of
SSL_get_error(3).
The following return values can currently occur for
SSL_want():
- SSL_NOTHING
- There is no data to be written or to be read.
- SSL_WRITING
- There are data in the SSL buffer that must be written to
the underlying BIO layer in order to complete the actual SSL_*()
operation. A call to SSL_get_error(3) should return
SSL_ERROR_WANT_WRITE.
- SSL_READING
- More data must be read from the underlying BIO layer
in order to complete the actual SSL_*() operation. A call to
SSL_get_error(3) should return SSL_ERROR_WANT_READ.
- 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 SSL_get_error(3) should return
SSL_ERROR_WANT_X509_LOOKUP.
- SSL_RETRY_VERIFY
- The operation did not complete because a certificate
verification callback has asked to be called again via
SSL_set_retry_verify(3). A call to SSL_get_error(3) should
return SSL_ERROR_WANT_RETRY_VERIFY.
- SSL_ASYNC_PAUSED
- An asynchronous operation partially completed and was then
paused. See SSL_get_all_async_fds(3). A call to
SSL_get_error(3) should return SSL_ERROR_WANT_ASYNC.
- 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 SSL_get_error(3) should
return SSL_ERROR_WANT_ASYNC_JOB.
- 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 SSL_get_error(3) should return
SSL_ERROR_WANT_CLIENT_HELLO_CB.
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.
ssl(7),
SSL_get_error(3)
The
SSL_want_client_hello_cb() function and the SSL_CLIENT_HELLO_CB
return value were added in OpenSSL 1.1.1.
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
<
https://www.openssl.org/source/license.html>.