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. 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.
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() 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)19/Jul/2002 0.9.6j SSL_connect(3)
