.\"	$OpenBSD: SSL_library_init.3,v 1.6 2018/03/27 17:35:50 schwarze Exp $
.\"	OpenSSL b97fdb57 Nov 11 09:33:09 2016 +0100
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.Dd $Mdocdate: March 27 2018 $
.Dt SSL_LIBRARY_INIT 3
.Os
.Sh NAME
.Nm SSL_library_init ,
.Nm OpenSSL_add_ssl_algorithms ,
.Nm SSLeay_add_ssl_algorithms
.Nd initialize SSL library by registering algorithms
.Sh SYNOPSIS
.In openssl/ssl.h
.Ft int
.Fn SSL_library_init void
.Ft int
.Fn OpenSSL_add_ssl_algorithms void
.Ft int
.Fn SSLeay_add_ssl_algorithms void
.Sh DESCRIPTION
.Fn SSL_library_init
registers the available SSL/TLS ciphers and digests.
.Pp
.Fn OpenSSL_add_ssl_algorithms
and
.Fn SSLeay_add_ssl_algorithms
are synonyms for
.Fn SSL_library_init
and are implemented as macros.
.Pp
.Fn SSL_library_init
must be called before any other action takes place.
.Fn SSL_library_init
is not reentrant.
.Pp
.Fn SSL_library_init
adds ciphers and digests used directly and indirectly by SSL/TLS.
.Sh RETURN VALUES
.Fn SSL_library_init
always returns 1, so it is safe to discard the return value.
.Sh EXAMPLES
A typical TLS/SSL application will start with the library initialization, and
provide readable error messages.
.Bd -literal
SSL_load_error_strings();                /* readable error messages */
SSL_library_init();                      /* initialize library */
.Ed
.Sh SEE ALSO
.Xr RAND_add 3 ,
.Xr ssl 3 ,
.Xr SSL_load_error_strings 3
.Sh HISTORY
.Fn SSLeay_add_ssl_algorithms
first appeared in SSLeay 0.8.0 and has been available since
.Ox 2.4 .
.Pp
.Fn SSL_library_init
first appeared in OpenSSL 0.9.2b and has been available since
.Ox 2.6 .
.Pp
.Fn OpenSSL_add_ssl_algorithms
first appeared in OpenSSL 0.9.5 and has been available since
.Ox 2.7 .