SSL_connect - initiate the TLS/SSL handshake with an TLS/SSL server
#include <openssl/ssl.h> int SSL_connect(SSL *ssl);
SSL_connect(3openssl) OpenSSL SSL_connect(3openssl)
NAME
SSL_connect - initiate the TLS/SSL handshake with an TLS/SSL server
SYNOPSIS
#include <openssl/ssl.h>
int SSL_connect(SSL *ssl);
DESCRIPTION
SSL_connect() initiates the TLS/SSL handshake with a server. The
communication channel must already have been set and assigned to the
ssl by setting an underlying BIO.
ATTRIBUTES
See attributes(7) for descriptions of the following attributes:
+---------------+--------------------------+
|ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+---------------+--------------------------+
|Availability | library/security/openssl |
+---------------+--------------------------+
|Stability | Pass-through uncommitted |
+---------------+--------------------------+
NOTES
The behaviour of SSL_connect() depends on the underlying BIO.
If the underlying BIO is blocking, SSL_connect() will only return once
the handshake has been finished or an error occurred.
If the underlying BIO is non-blocking, SSL_connect() will also return
when the underlying BIO could not satisfy the needs of SSL_connect() 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_connect() will yield SSL_ERROR_WANT_READ or SSL_ERROR_WANT_WRITE.
The calling process then must repeat the call after taking appropriate
action to satisfy the needs of SSL_connect(). 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.
Source code for open source software components in Oracle Solaris can
be found at https://www.oracle.com/downloads/opensource/solaris-source-
code-downloads.html.
This software was built from source available at
https://github.com/oracle/solaris-userland. The original community
source was downloaded from
https://www.openssl.org/source/openssl-1.0.2ze.tar.gz.
Further information about this software can be found on the open source
community website at https://www.openssl.org/.
RETURN VALUES
The following return values can occur:
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 ret to find out the reason.
1 The TLS/SSL handshake was successfully completed, a TLS/SSL
connection has been established.
<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 ret to find out the reason.
SEE ALSO
SSL_get_error(3), SSL_accept(3), SSL_shutdown(3), ssl(3), bio(3),
SSL_set_connect_state(3), SSL_do_handshake(3), SSL_CTX_new(3)
1.0.2ze 2022-05-03 SSL_connect(3openssl)