env: Handle write-once ethaddr and serial# generically

Use the variable access flags to implement the protection for ethaddr
and serial# instead of hard-coding them.

Signed-off-by: Joe Hershberger <joe.hershberger@ni.com>

common/env_flags.c

@@ -503,25 +503,6 @@ int env_flags_validate(const ENTRY *item, const char *newval, enum env_op op,
 	/* Default value for NULL to protect string-manipulating functions */
 	newval = newval ? : "";
 
-#ifndef CONFIG_ENV_OVERWRITE
-	/*
-	 * Some variables like "ethaddr" and "serial#" can be set only once and
-	 * cannot be deleted, unless CONFIG_ENV_OVERWRITE is defined.
-	 */
-	if (op != env_op_create &&		/* variable exists */
-		(flag & H_FORCE) == 0) {	/* and we are not forced */
-		if (strcmp(name, "serial#") == 0 ||
-		    (strcmp(name, "ethaddr") == 0
-#if defined(CONFIG_OVERWRITE_ETHADDR_ONCE) && defined(CONFIG_ETHADDR)
-		     && strcmp(oldval, __stringify(CONFIG_ETHADDR)) != 0
-#endif	/* CONFIG_OVERWRITE_ETHADDR_ONCE && CONFIG_ETHADDR */
-			)) {
-			printf("Can't overwrite \"%s\"\n", name);
-			return 1;
-		}
-	}
-#endif
-
 	/* validate the value to match the variable type */
 	if (op != env_op_delete) {
 		enum env_flags_vartype type = (enum env_flags_vartype)

include/env_flags.h

@@ -53,7 +53,29 @@ enum env_flags_varaccess {
 #define CONFIG_ENV_FLAGS_LIST_STATIC ""
 #endif
 
+#ifdef CONFIG_CMD_NET
+#ifdef CONFIG_ENV_OVERWRITE
+#define ETHADDR_FLAGS "ethaddr:ma,"
+#else
+#ifdef CONFIG_OVERWRITE_ETHADDR_ONCE
+#define ETHADDR_FLAGS "ethaddr:mc,"
+#else
+#define ETHADDR_FLAGS "ethaddr:mo,"
+#endif
+#endif
+#else
+#define ETHADDR_FLAGS ""
+#endif
+
+#ifndef CONFIG_ENV_OVERWRITE
+#define SERIAL_FLAGS "serial#:so,"
+#else
+#define SERIAL_FLAGS ""
+#endif
+
 #define ENV_FLAGS_LIST_STATIC \
+	ETHADDR_FLAGS \
+	SERIAL_FLAGS \
 	CONFIG_ENV_FLAGS_LIST_STATIC
 
 #ifdef CONFIG_CMD_ENV_FLAGS

tools/env/fw_env.c

@@ -369,23 +369,6 @@ int fw_env_write(char *name, char *value)
 		return 0;
 
 	if (deleting || overwriting) {
-#ifndef CONFIG_ENV_OVERWRITE
-		/*
-		 * Ethernet Address and serial# can be set only once
-		 */
-		if (
-		    (strcmp(name, "serial#") == 0) ||
-		    ((strcmp(name, "ethaddr") == 0)
-#if defined(CONFIG_OVERWRITE_ETHADDR_ONCE) && defined(CONFIG_ETHADDR)
-		    && (strcmp(oldval, __stringify(CONFIG_ETHADDR)) != 0)
-#endif /* CONFIG_OVERWRITE_ETHADDR_ONCE && CONFIG_ETHADDR */
-		   ) ) {
-			fprintf (stderr, "Can't overwrite \"%s\"\n", name);
-			errno = EROFS;
-			return -1;
-		}
-#endif /* CONFIG_ENV_OVERWRITE */
-
 		if (*++nxt == '\0') {
 			*env = '\0';
 		} else {