v4.19.13 snapshot.
diff --git a/lib/net_utils.c b/lib/net_utils.c
new file mode 100644
index 0000000..af52535
--- /dev/null
+++ b/lib/net_utils.c
@@ -0,0 +1,27 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/string.h>
+#include <linux/if_ether.h>
+#include <linux/ctype.h>
+#include <linux/kernel.h>
+
+bool mac_pton(const char *s, u8 *mac)
+{
+ int i;
+
+ /* XX:XX:XX:XX:XX:XX */
+ if (strlen(s) < 3 * ETH_ALEN - 1)
+ return false;
+
+ /* Don't dirty result unless string is valid MAC. */
+ for (i = 0; i < ETH_ALEN; i++) {
+ if (!isxdigit(s[i * 3]) || !isxdigit(s[i * 3 + 1]))
+ return false;
+ if (i != ETH_ALEN - 1 && s[i * 3 + 2] != ':')
+ return false;
+ }
+ for (i = 0; i < ETH_ALEN; i++) {
+ mac[i] = (hex_to_bin(s[i * 3]) << 4) | hex_to_bin(s[i * 3 + 1]);
+ }
+ return true;
+}
+EXPORT_SYMBOL(mac_pton);