ssl_client2, ssl_server2: code optimization + guards adaptation

Signed-off-by: Przemek Stekiel <przemyslaw.stekiel@mobica.com>
diff --git a/programs/ssl/ssl_server2.c b/programs/ssl/ssl_server2.c
index 1986b35..715fe0c 100644
--- a/programs/ssl/ssl_server2.c
+++ b/programs/ssl/ssl_server2.c
@@ -446,7 +446,9 @@
 #define USAGE_EARLY_DATA ""
 #endif /* MBEDTLS_SSL_EARLY_DATA */
 
-#if defined(MBEDTLS_ECP_LIGHT)
+#if defined(MBEDTLS_ECP_LIGHT) || \
+    (defined(MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_SOME_EPHEMERAL_ENABLED) && \
+    defined(PSA_WANT_ALG_FFDH))
 #define USAGE_CURVES \
     "    curves=a,b,c,d      default: \"default\" (library default)\n"  \
     "                        example: \"secp521r1,brainpoolP512r1\"\n"  \
@@ -1522,7 +1524,6 @@
 #endif
 #if defined(MBEDTLS_ECP_LIGHT)
     uint16_t group_list[CURVE_LIST_SIZE];
-    const mbedtls_ecp_curve_info *curve_cur;
 #endif
 #if defined(MBEDTLS_SSL_ALPN)
     const char *alpn_list[ALPN_LIST_SIZE];
@@ -2387,62 +2388,16 @@
     }
 #endif /* MBEDTLS_SSL_HANDSHAKE_WITH_PSK_ENABLED */
 
-#if defined(MBEDTLS_ECP_LIGHT)
+#if defined(MBEDTLS_ECP_LIGHT) || \
+    (defined(MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_SOME_EPHEMERAL_ENABLED) && \
+    defined(PSA_WANT_ALG_FFDH))
     if (opt.curves != NULL) {
-        p = (char *) opt.curves;
-        i = 0;
-
-        if (strcmp(p, "none") == 0) {
-            group_list[0] = 0;
-        } else if (strcmp(p, "default") != 0) {
-            /* Leave room for a final NULL in curve list */
-            while (i < CURVE_LIST_SIZE - 1 && *p != '\0') {
-                q = p;
-                uint16_t ffdh_group = 0;
-
-                /* Terminate the current string */
-                while (*p != ',' && *p != '\0') {
-                    p++;
-                }
-                if (*p == ',') {
-                    *p++ = '\0';
-                }
-
-                if ((curve_cur = mbedtls_ecp_curve_info_from_name(q)) != NULL) {
-                    group_list[i++] = curve_cur->tls_id;
-                } else if ((ffdh_group = mbedtls_ssl_ffdh_group_from_name(q)) != 0) {
-                    group_list[i++] = ffdh_group;
-                } else {
-                    mbedtls_printf("unknown curve %s\n", q);
-                    mbedtls_printf("supported curves: ");
-                    for (curve_cur = mbedtls_ecp_curve_list();
-                         curve_cur->grp_id != MBEDTLS_ECP_DP_NONE;
-                         curve_cur++) {
-                        mbedtls_printf("%s ", curve_cur->name);
-                        const uint16_t *supported_ffdh_group = mbedtls_ssl_ffdh_supported_groups();
-                        while (*supported_ffdh_group != 0) {
-                            mbedtls_printf("%s ",
-                                           mbedtls_ssl_ffdh_name_from_group(*supported_ffdh_group));
-                            supported_ffdh_group++;
-                        }
-                    }
-                    mbedtls_printf("\n");
-                    goto exit;
-                }
-            }
-
-            mbedtls_printf("Number of curves: %d\n", i);
-
-            if (i == CURVE_LIST_SIZE - 1 && *p != '\0') {
-                mbedtls_printf("curves list too long, maximum %d",
-                               CURVE_LIST_SIZE - 1);
-                goto exit;
-            }
-
-            group_list[i] = 0;
+        if (parse_curves(opt.curves, group_list, CURVE_LIST_SIZE) != 0) {
+            goto exit;
         }
     }
-#endif /* MBEDTLS_ECP_LIGHT */
+#endif /* MBEDTLS_ECP_LIGHT ||
+          (MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_SOME_EPHEMERAL_ENABLED && PSA_WANT_ALG_FFDH) */
 
 #if defined(MBEDTLS_SSL_HANDSHAKE_WITH_CERT_ENABLED)
     if (opt.sig_algs != NULL) {
@@ -3144,7 +3099,9 @@
     }
 #endif
 
-#if defined(MBEDTLS_ECP_LIGHT)
+#if defined(MBEDTLS_ECP_LIGHT) || \
+    (defined(MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_SOME_EPHEMERAL_ENABLED) && \
+    defined(PSA_WANT_ALG_FFDH))
     if (opt.curves != NULL &&
         strcmp(opt.curves, "default") != 0) {
         mbedtls_ssl_conf_groups(&conf, group_list);