Merge pull request #24570 from topimiettinen/nft-sets-v2

network: firewall integration with NFT sets

src/basic/parse-util.c

@@ -747,3 +747,22 @@ int parse_loadavg_fixed_point(const char *s, loadavg_t *ret) {
 
         return store_loadavg_fixed_point(i, f, ret);
 }
+
+/* Limitations are described in https://www.netfilter.org/projects/nftables/manpage.html and
+ * https://bugzilla.netfilter.org/show_bug.cgi?id=1175 */
+bool nft_identifier_valid(const char *id) {
+        if (!id)
+                return false;
+
+        size_t len = strlen(id);
+        if (len == 0 || len > 31)
+                return false;
+
+        if (!ascii_isalpha(id[0]))
+                return false;
+
+        for (size_t i = 1; i < len; i++)
+                if (!ascii_isalpha(id[i]) && !ascii_isdigit(id[i]) && !IN_SET(id[i], '/', '\\', '_', '.'))
+                        return false;
+        return true;
+}

src/basic/parse-util.h

@@ -152,3 +152,5 @@ int parse_oom_score_adjust(const char *s, int *ret);
  * to a loadavg_t. */
 int store_loadavg_fixed_point(unsigned long i, unsigned long f, loadavg_t *ret);
 int parse_loadavg_fixed_point(const char *s, loadavg_t *ret);
+
+bool nft_identifier_valid(const char *id);