mirror of
https://github.com/openssl/openssl.git
synced 2024-11-27 05:21:51 +08:00
104 lines
3.7 KiB
Plaintext
104 lines
3.7 KiB
Plaintext
=pod
|
|
|
|
=head1 NAME
|
|
|
|
SSL_CTX_set1_curves, SSL_CTX_set1_curves_list, SSL_set1_curves,
|
|
SSL_set1_curves_list, SSL_get1_curves, SSL_get_shared_curve,
|
|
SSL_CTX_set_ecdh_auto, SSL_set_ecdh_auto - EC supported curve functions
|
|
|
|
=head1 SYNOPSIS
|
|
|
|
#include <openssl/ssl.h>
|
|
|
|
int SSL_CTX_set1_curves(SSL_CTX *ctx, int *clist, int clistlen);
|
|
int SSL_CTX_set1_curves_list(SSL_CTX *ctx, char *list);
|
|
|
|
int SSL_set1_curves(SSL *ssl, int *clist, int clistlen);
|
|
int SSL_set1_curves_list(SSL *ssl, char *list);
|
|
|
|
int SSL_get1_curves(SSL *ssl, int *curves);
|
|
int SSL_get_shared_curve(SSL *s, int n);
|
|
|
|
int SSL_CTX_set_ecdh_auto(SSL_CTX *ctx, int onoff);
|
|
int SSL_set_ecdh_auto(SSL *s, int onoff);
|
|
|
|
=head1 DESCRIPTION
|
|
|
|
SSL_CTX_set1_curves() sets the supported curves for B<ctx> to B<clistlen>
|
|
curves in the array B<clist>. The array consist of all NIDs of curves in
|
|
preference order. For a TLS client the curves are used directly in the
|
|
supported curves extension. For a TLS server the curves are used to
|
|
determine the set of shared curves.
|
|
|
|
SSL_CTX_set1_curves_list() sets the supported curves for B<ctx> to
|
|
string B<list>. The string is a colon separated list of curve NIDs or
|
|
names, for example "P-521:P-384:P-256".
|
|
|
|
SSL_set1_curves() and SSL_set1_curves_list() are similar except they set
|
|
supported curves for the SSL structure B<ssl>.
|
|
|
|
SSL_get1_curves() returns the set of supported curves sent by a client
|
|
in the supported curves extension. It returns the total number of
|
|
supported curves. The B<curves> parameter can be B<NULL> to simply
|
|
return the number of curves for memory allocation purposes. The
|
|
B<curves> array is in the form of a set of curve NIDs in preference
|
|
order. It can return zero if the client did not send a supported curves
|
|
extension.
|
|
|
|
SSL_get_shared_curve() returns shared curve B<n> for a server-side
|
|
SSL B<ssl>. If B<n> is -1 then the total number of shared curves is
|
|
returned, which may be zero. Other than for diagnostic purposes,
|
|
most applications will only be interested in the first shared curve
|
|
so B<n> is normally set to zero. If the value B<n> is out of range,
|
|
NID_undef is returned.
|
|
|
|
SSL_CTX_set_ecdh_auto() and SSL_set_ecdh_auto() set automatic curve
|
|
selection for server B<ctx> or B<ssl> to B<onoff>. If B<onoff> is 1 then
|
|
the highest preference curve is automatically used for ECDH temporary
|
|
keys used during key exchange.
|
|
|
|
All these functions are implemented as macros.
|
|
|
|
=head1 NOTES
|
|
|
|
If an application wishes to make use of several of these functions for
|
|
configuration purposes either on a command line or in a file it should
|
|
consider using the SSL_CONF interface instead of manually parsing options.
|
|
|
|
The functions SSL_CTX_set_ecdh_auto() and SSL_set_ecdh_auto() can be used to
|
|
make a server always choose the most appropriate curve for a client. If set
|
|
it will override any temporary ECDH parameters set by a server. Previous
|
|
versions of OpenSSL could effectively only use a single ECDH curve set
|
|
using a function such as SSL_CTX_set_ecdh_tmp(). Newer applications should
|
|
just call:
|
|
|
|
SSL_CTX_set_ecdh_auto(ctx, 1);
|
|
|
|
and they will automatically support ECDH using the most appropriate shared
|
|
curve.
|
|
|
|
=head1 RETURN VALUES
|
|
|
|
SSL_CTX_set1_curves(), SSL_CTX_set1_curves_list(), SSL_set1_curves(),
|
|
SSL_set1_curves_list(), SSL_CTX_set_ecdh_auto() and SSL_set_ecdh_auto()
|
|
return 1 for success and 0 for failure.
|
|
|
|
SSL_get1_curves() returns the number of curves, which may be zero.
|
|
|
|
SSL_get_shared_curve() returns the NID of shared curve B<n> or NID_undef if there
|
|
is no shared curve B<n>; or the total number of shared curves if B<n>
|
|
is -1.
|
|
|
|
When called on a client B<ssl>, SSL_get_shared_curve() has no meaning and
|
|
returns -1.
|
|
|
|
=head1 SEE ALSO
|
|
|
|
L<SSL_CTX_add_extra_chain_cert(3)|SSL_CTX_add_extra_chain_cert(3)>
|
|
|
|
=head1 HISTORY
|
|
|
|
These functions were first added to OpenSSL 1.0.2.
|
|
|
|
=cut
|