EVP: Add EVP_PKEY_get_group_name() to extract the group name of a pkey

This replaces the internal evp_pkey_get_EC_KEY_curve_nid()

Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Tomas Mraz <tmraz@fedoraproject.org>
(Merged from https://github.com/openssl/openssl/pull/13436)

1 files changed, 46 insertions, 0 deletions

diff --git a/doc/man3/EVP_PKEY_get_group_name.pod b/doc/man3/EVP_PKEY_get_group_name.pod
new file mode 100644
index 0000000000..964d6b8007
--- /dev/null
+++ b/doc/man3/EVP_PKEY_get_group_name.pod
@@ -0,0 +1,46 @@
+=pod
+
+=head1 NAME
+
+EVP_PKEY_get_group_name - get private key group name
+
+=head1 SYNOPSIS
+
+ #include <openssl/evp.h>
+
+ int EVP_PKEY_get_group_name(EVP_PKEY *pkey, char *gname, size_t gname_sz,
+                             size_t *gname_len);
+
+=head1 DESCRIPTION
+
+EVP_PKEY_get_group_name() fills in the group name of the I<pkey> into
+I<gname>, up to at most I<gname_sz> bytes including the ending NUL byte
+and assigns I<*gname_len> the actual size of the name, if I<pkey>'s key type
+supports it.
+I<gname> as well as I<gname_len> may individually be NULL, and won't be
+filled in or assigned in that case.
+
+=head1 NOTES
+
+Among the standard OpenSSL key types, this is only supported for DH, EC and
+SM2 keys.  Other providers may support this for additional key types.
+
+=head1 RETURN VALUES
+
+EVP_PKEY_get_group_name() returns 1 if the group name could be filled in,
+otherwise 0.
+
+=head1 HISTORY
+
+This function was added in OpenSSL 3.0.
+
+=head1 COPYRIGHT
+
+Copyright 2020 The OpenSSL Project Authors. All Rights Reserved.
+
+Licensed under the Apache License 2.0 (the "License").  You may not use
+this file except in compliance with the License.  You can obtain a copy
+in the file LICENSE in the source distribution or at
+L<https://www.openssl.org/source/license.html>.
+
+=cut