5 SSL_CTX_set1_groups, SSL_CTX_set1_groups_list, SSL_set1_groups,
6 SSL_set1_groups_list, SSL_get1_groups, SSL_get_shared_group,
7 SSL_CTX_set1_curves, SSL_CTX_set1_curves_list, SSL_set1_curves,
8 SSL_set1_curves_list, SSL_get1_curves, SSL_get_shared_curve
9 - EC supported curve functions
13 #include <openssl/ssl.h>
15 int SSL_CTX_set1_groups(SSL_CTX *ctx, int *glist, int glistlen);
16 int SSL_CTX_set1_groups_list(SSL_CTX *ctx, char *list);
18 int SSL_set1_groups(SSL *ssl, int *glist, int glistlen);
19 int SSL_set1_groups_list(SSL *ssl, char *list);
21 int SSL_get1_groups(SSL *ssl, int *groups);
22 int SSL_get_shared_group(SSL *s, int n);
24 int SSL_CTX_set1_curves(SSL_CTX *ctx, int *clist, int clistlen);
25 int SSL_CTX_set1_curves_list(SSL_CTX *ctx, char *list);
27 int SSL_set1_curves(SSL *ssl, int *clist, int clistlen);
28 int SSL_set1_curves_list(SSL *ssl, char *list);
30 int SSL_get1_curves(SSL *ssl, int *curves);
31 int SSL_get_shared_curve(SSL *s, int n);
35 For all of the functions below that set the supported groups there must be at
36 least one group in the list.
38 SSL_CTX_set1_groups() sets the supported groups for B<ctx> to B<glistlen>
39 groups in the array B<glist>. The array consist of all NIDs of groups in
40 preference order. For a TLS client the groups are used directly in the
41 supported groups extension. For a TLS server the groups are used to
42 determine the set of shared groups.
44 SSL_CTX_set1_groups_list() sets the supported groups for B<ctx> to
45 string B<list>. The string is a colon separated list of group NIDs or
46 names, for example "P-521:P-384:P-256".
48 SSL_set1_groups() and SSL_set1_groups_list() are similar except they set
49 supported groups for the SSL structure B<ssl>.
51 SSL_get1_groups() returns the set of supported groups sent by a client
52 in the supported groups extension. It returns the total number of
53 supported groups. The B<groups> parameter can be B<NULL> to simply
54 return the number of groups for memory allocation purposes. The
55 B<groups> array is in the form of a set of group NIDs in preference
56 order. It can return zero if the client did not send a supported groups
59 SSL_get_shared_group() returns shared group B<n> for a server-side
60 SSL B<ssl>. If B<n> is -1 then the total number of shared groups is
61 returned, which may be zero. Other than for diagnostic purposes,
62 most applications will only be interested in the first shared group
63 so B<n> is normally set to zero. If the value B<n> is out of range,
64 NID_undef is returned.
66 All these functions are implemented as macros.
68 The curve functions are synonyms for the equivalently named group functions and
69 are identical in every respect. They exist because, prior to TLS1.3, there was
70 only the concept of supported curves. In TLS1.3 this was renamed to supported
71 groups, and extended to include Diffie Hellman groups. The group functions
72 should be used in preference.
76 If an application wishes to make use of several of these functions for
77 configuration purposes either on a command line or in a file it should
78 consider using the SSL_CONF interface instead of manually parsing options.
82 SSL_CTX_set1_groups(), SSL_CTX_set1_groups_list(), SSL_set1_groups() and
83 SSL_set1_groups_list(), return 1 for success and 0 for failure.
85 SSL_get1_groups() returns the number of groups, which may be zero.
87 SSL_get_shared_group() returns the NID of shared group B<n> or NID_undef if there
88 is no shared group B<n>; or the total number of shared groups if B<n>
91 When called on a client B<ssl>, SSL_get_shared_group() has no meaning and
96 L<SSL_CTX_add_extra_chain_cert(3)>
100 The curve functions were first added to OpenSSL 1.0.2. The equivalent group
101 functions were first added to OpenSSL 1.1.1.
105 Copyright 2013-2018 The OpenSSL Project Authors. All Rights Reserved.
107 Licensed under the OpenSSL license (the "License"). You may not use
108 this file except in compliance with the License. You can obtain a copy
109 in the file LICENSE in the source distribution or at
110 L<https://www.openssl.org/source/license.html>.