NAME
SSL_want
,
SSL_want_nothing
,
SSL_want_read
,
SSL_want_write
,
SSL_want_x509_lookup
—
obtain state information TLS/SSL I/O
operation
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);
DESCRIPTION
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 those 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
non-blocking 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).
RETURN VALUES
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 returnSSL_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 returnSSL_ERROR_WANT_READ
. SSL_X509_LOOKUP
- The operation did not complete because an application callback set by
SSL_CTX_set_client_cert_cb(3) has asked to be called again.
A call to
SSL_get_error(3) should return
SSL_ERROR_WANT_X509_LOOKUP
.
SSL_want_nothing
(),
SSL_want_read
(),
SSL_want_write
(), and
SSL_want_x509_lookup
() return 1 when the
corresponding condition is true or 0 otherwise.
SEE ALSO
HISTORY
These functions appeared before SSLeay 0.8 and have been available since OpenBSD 2.4.