openssl/doc/ssl/SSL_accept.pod
Nick Alcock ae5c1ca377 Fix POD errors to stop make install_docs dying with pod2man 2.5.0+
podlators 2.5.0 has switched to dying on POD syntax errors. This means
that a bunch of long-standing erroneous POD in the openssl documentation
now leads to fatal errors from pod2man, halting installation.

Unfortunately POD constraints mean that you have to sort numeric lists
in ascending order if they start with 1: you cannot do 1, 0, 2 even if
you want 1 to appear first. I've reshuffled such (alas, I wish there
were a better way but I don't know of one).
(cherry picked from commit 5cc2707742)
2013-02-15 19:39:59 +01:00

76 lines
2.5 KiB
Text

=pod
=head1 NAME
SSL_accept - wait for a TLS/SSL client to initiate a TLS/SSL handshake
=head1 SYNOPSIS
#include <openssl/ssl.h>
int SSL_accept(SSL *ssl);
=head1 DESCRIPTION
SSL_accept() waits for a TLS/SSL client to initiate the TLS/SSL handshake.
The communication channel must already have been set and assigned to the
B<ssl> by setting an underlying B<BIO>.
=head1 NOTES
The behaviour of SSL_accept() depends on the underlying BIO.
If the underlying BIO is B<blocking>, SSL_accept() will only return once the
handshake has been finished or an error occurred, except for SGC (Server
Gated Cryptography). For SGC, SSL_accept() may return with -1, but
SSL_get_error() will yield B<SSL_ERROR_WANT_READ/WRITE> and SSL_accept()
should be called again.
If the underlying BIO is B<non-blocking>, SSL_accept() will also return
when the underlying BIO could not satisfy the needs of SSL_accept()
to continue the handshake, indicating the problem by the return value -1.
In this case a call to SSL_get_error() with the
return value of SSL_accept() will yield B<SSL_ERROR_WANT_READ> or
B<SSL_ERROR_WANT_WRITE>. The calling process then must repeat the call after
taking appropriate action to satisfy the needs of SSL_accept().
The action depends on the underlying BIO. When using a non-blocking socket,
nothing is to be done, but select() can be used to check for the required
condition. When using a buffering BIO, like a BIO pair, data must be written
into or retrieved out of the BIO before being able to continue.
=head1 RETURN VALUES
The following return values can occur:
=over 4
=item 0
The TLS/SSL handshake was not successful but was shut down controlled and
by the specifications of the TLS/SSL protocol. Call SSL_get_error() with the
return value B<ret> to find out the reason.
=item 1
The TLS/SSL handshake was successfully completed, a TLS/SSL connection has been
established.
=item E<lt>0
The TLS/SSL handshake was not successful because a fatal error occurred either
at the protocol level or a connection failure occurred. The shutdown was
not clean. It can also occur of action is need to continue the operation
for non-blocking BIOs. Call SSL_get_error() with the return value B<ret>
to find out the reason.
=back
=head1 SEE ALSO
L<SSL_get_error(3)|SSL_get_error(3)>, L<SSL_connect(3)|SSL_connect(3)>,
L<SSL_shutdown(3)|SSL_shutdown(3)>, L<ssl(3)|ssl(3)>, L<bio(3)|bio(3)>,
L<SSL_set_connect_state(3)|SSL_set_connect_state(3)>,
L<SSL_do_handshake(3)|SSL_do_handshake(3)>,
L<SSL_CTX_new(3)|SSL_CTX_new(3)>
=cut