SSL_CONNECT(3) OpenSSL SSL_CONNECT(3)NAMESSL_connect - initiate the TLS/SSL handshake with an TLS/SSL
server
SYNOPSIS
#include <openssl/ssl.h>
int SSL_connect(SSL *ssl);
DESCRIPTIONSSL_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.
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 cal-
ling 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.
RETURN VALUES
The following return values can occur:
1 The TLS/SSL handshake was successfully completed, a
TLS/SSL connection has been established.
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.
<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()MirOS BSD #10-current 2005-02-05 1
SSL_CONNECT(3) OpenSSL SSL_CONNECT(3)
with the return value ret to find out the reason.
SEE ALSOSSL_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)MirOS BSD #10-current 2005-02-05 2
