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)

2 files changed, 56 insertions, 43 deletions

diff --git a/crypto/evp/evp_err.c b/crypto/evp/evp_err.c
index 3a4253b353..c2259f0beb 100644
--- a/crypto/evp/evp_err.c
+++ b/crypto/evp/evp_err.c
@@ -176,6 +176,8 @@ static const ERR_STRING_DATA EVP_str_reasons[] = {
     "unsupported key derivation function"},
     {ERR_PACK(ERR_LIB_EVP, 0, EVP_R_UNSUPPORTED_KEY_SIZE),
     "unsupported key size"},
+    {ERR_PACK(ERR_LIB_EVP, 0, EVP_R_UNSUPPORTED_KEY_TYPE),
+    "unsupported key type"},
     {ERR_PACK(ERR_LIB_EVP, 0, EVP_R_UNSUPPORTED_NUMBER_OF_ROUNDS),
     "unsupported number of rounds"},
     {ERR_PACK(ERR_LIB_EVP, 0, EVP_R_UNSUPPORTED_PRF), "unsupported prf"},
diff --git a/crypto/evp/p_lib.c b/crypto/evp/p_lib.c
index af14706939..6211019b62 100644
--- a/crypto/evp/p_lib.c
+++ b/crypto/evp/p_lib.c
@@ -32,10 +32,10 @@
 #include <openssl/encoder.h>
 #include <openssl/core_names.h>
 
+#include "internal/ffc.h"
 #include "crypto/asn1.h"
 #include "crypto/evp.h"
 #include "crypto/ecx.h"
-#include "internal/evp.h"
 #include "internal/provider.h"
 #include "evp_local.h"
 
@@ -1056,48 +1056,6 @@ int EVP_PKEY_can_sign(const EVP_PKEY *pkey)
     return 0;
 }
 
-#ifndef OPENSSL_NO_EC
-/*
- * TODO rewrite when we have proper data extraction functions
- * Note: an octet pointer would be desirable!
- */
-static OSSL_CALLBACK get_ec_curve_name_cb;
-static int get_ec_curve_name_cb(const OSSL_PARAM params[], void *arg)
-{
-    const OSSL_PARAM *p = NULL;
-
-    if ((p = OSSL_PARAM_locate_const(params, OSSL_PKEY_PARAM_GROUP_NAME)) != NULL)
-        return OSSL_PARAM_get_utf8_string(p, arg, 0);
-
-    /* If there is no curve name, this is not an EC key */
-    return 0;
-}
-
-int evp_pkey_get_EC_KEY_curve_nid(const EVP_PKEY *pkey)
-{
-    int ret = NID_undef;
-
-    if (pkey->keymgmt == NULL) {
-        if (EVP_PKEY_base_id(pkey) == EVP_PKEY_EC) {
-            EC_KEY *ec = EVP_PKEY_get0_EC_KEY(pkey);
-
-            ret = EC_GROUP_get_curve_name(EC_KEY_get0_group(ec));
-        }
-    } else if (EVP_PKEY_is_a(pkey, "EC") || EVP_PKEY_is_a(pkey, "SM2")) {
-        char *curve_name = NULL;
-
-        ret = evp_keymgmt_util_export(pkey,
-                                      OSSL_KEYMGMT_SELECT_DOMAIN_PARAMETERS,
-                                      get_ec_curve_name_cb, &curve_name);
-        if (ret)
-            ret = ec_curve_name2nid(curve_name);
-        OPENSSL_free(curve_name);
-    }
-
-    return ret;
-}
-#endif
-
 static int print_reset_indent(BIO **out, int pop_f_prefix, long saved_indent)
 {
     BIO_set_indent(*out, saved_indent);
@@ -1259,6 +1217,59 @@ int EVP_PKEY_get_default_digest_name(EVP_PKEY *pkey,
     }
 }
 
+int EVP_PKEY_get_group_name(const EVP_PKEY *pkey, char *gname, size_t gname_sz,
+                            size_t *gname_len)
+{
+    if (evp_pkey_is_legacy(pkey)) {
+        const char *name = NULL;
+
+        switch (EVP_PKEY_base_id(pkey)) {
+#ifndef OPENSSL_NO_EC
+        case EVP_PKEY_EC:
+            {
+                EC_KEY *ec = EVP_PKEY_get0_EC_KEY(pkey);
+                int nid = EC_GROUP_get_curve_name(EC_KEY_get0_group(ec));
+
+                if (nid != NID_undef)
+                    name = ec_curve_nid2name(nid);
+            }
+            break;
+#endif
+#ifndef OPENSSL_NO_DH
+        case EVP_PKEY_DH:
+            {
+                DH *dh = EVP_PKEY_get0_DH(pkey);
+                int uid = DH_get_nid(dh);
+
+                if (uid != NID_undef)
+                    name = ossl_ffc_named_group_from_uid(uid);
+            }
+            break;
+#endif
+        default:
+            break;
+        }
+
+        if (gname_len != NULL)
+            *gname_len = (name == NULL ? 0 : strlen(name));
+        if (name != NULL) {
+            if (gname != NULL)
+                OPENSSL_strlcpy(gname, name, gname_sz);
+            return 1;
+        }
+    } else if (evp_pkey_is_provided(pkey)) {
+        if (EVP_PKEY_get_utf8_string_param(pkey, OSSL_PKEY_PARAM_GROUP_NAME,
+                                           gname, gname_sz, gname_len))
+            return 1;
+    } else {
+        ERR_raise(ERR_LIB_EVP, EVP_R_INVALID_KEY);
+        return 0;
+    }
+
+    ERR_raise(ERR_LIB_EVP, EVP_R_UNSUPPORTED_KEY_TYPE);
+    return 0;
+}
+
 int EVP_PKEY_supports_digest_nid(EVP_PKEY *pkey, int nid)
 {
     int rv, default_nid;