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. Currently supported groups for
43 B<TLSv1.3> are B<NID_X9_62_prime256v1>, B<NID_secp384r1>, B<NID_secp521r1>,
44 B<NID_X25519>, B<NID_X448>, B<NID_ffdhe2048>, B<NID_ffdhe3072>,
45 B<NID_ffdhe4096>, B<NID_ffdhe6144> and B<NID_ffdhe8192>.
47 SSL_CTX_set1_groups_list() sets the supported groups for B<ctx> to
48 string B<list>. The string is a colon separated list of group NIDs or
49 names, for example "P-521:P-384:P-256:X25519:ffdhe2048". Currently supported
50 groups for B<TLSv1.3> are B<P-256>, B<P-384>, B<P-521>, B<X25519>, B<X448>,
51 B<ffdhe2048>, B<ffdhe3072>, B<ffdhe4096>, B<ffdhe6144>, B<ffdhe8192>.
53 SSL_set1_groups() and SSL_set1_groups_list() are similar except they set
54 supported groups for the SSL structure B<ssl>.
56 SSL_get1_groups() returns the set of supported groups sent by a client
57 in the supported groups extension. It returns the total number of
58 supported groups. The B<groups> parameter can be B<NULL> to simply
59 return the number of groups for memory allocation purposes. The
60 B<groups> array is in the form of a set of group NIDs in preference
61 order. It can return zero if the client did not send a supported groups
64 SSL_get_shared_group() returns shared group B<n> for a server-side
65 SSL B<ssl>. If B<n> is -1 then the total number of shared groups is
66 returned, which may be zero. Other than for diagnostic purposes,
67 most applications will only be interested in the first shared group
68 so B<n> is normally set to zero. If the value B<n> is out of range,
69 NID_undef is returned.
71 All these functions are implemented as macros.
73 The curve functions are synonyms for the equivalently named group functions and
74 are identical in every respect. They exist because, prior to TLS1.3, there was
75 only the concept of supported curves. In TLS1.3 this was renamed to supported
76 groups, and extended to include Diffie Hellman groups. The group functions
77 should be used in preference.
81 If an application wishes to make use of several of these functions for
82 configuration purposes either on a command line or in a file it should
83 consider using the SSL_CONF interface instead of manually parsing options.
87 SSL_CTX_set1_groups(), SSL_CTX_set1_groups_list(), SSL_set1_groups() and
88 SSL_set1_groups_list(), return 1 for success and 0 for failure.
90 SSL_get1_groups() returns the number of groups, which may be zero.
92 SSL_get_shared_group() returns the NID of shared group B<n> or NID_undef if there
93 is no shared group B<n>; or the total number of shared groups if B<n>
96 When called on a client B<ssl>, SSL_get_shared_group() has no meaning and
101 L<SSL_CTX_add_extra_chain_cert(3)>
105 The curve functions were added in OpenSSL 1.0.2. The equivalent group
106 functions were added in OpenSSL 1.1.1.
110 Copyright 2013-2018 The OpenSSL Project Authors. All Rights Reserved.
112 Licensed under the Apache License 2.0 (the "License"). You may not use
113 this file except in compliance with the License. You can obtain a copy
114 in the file LICENSE in the source distribution or at
115 L<https://www.openssl.org/source/license.html>.