net: core: move mac_pton() to lib/net_utils.c

Since we have at least one user of this function outside of CONFIG_NET
scope, we have to provide this function independently. The proposed
solution is to move it under lib/net_utils.c with corresponding
configuration variable and select wherever it is needed.

Signed-off-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reported-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

lib/Kconfig

@@ -22,6 +22,9 @@ config GENERIC_STRNCPY_FROM_USER
 config GENERIC_STRNLEN_USER
 	bool
 
+config GENERIC_NET_UTILS
+	bool
+
 config GENERIC_FIND_FIRST_BIT
 	bool
 

lib/Makefile

@@ -137,6 +137,8 @@ obj-$(CONFIG_DDR) += jedec_ddr_data.o
 obj-$(CONFIG_GENERIC_STRNCPY_FROM_USER) += strncpy_from_user.o
 obj-$(CONFIG_GENERIC_STRNLEN_USER) += strnlen_user.o
 
+obj-$(CONFIG_GENERIC_NET_UTILS) += net_utils.o
+
 obj-$(CONFIG_STMP_DEVICE) += stmp_device.o
 
 libfdt_files = fdt.o fdt_ro.o fdt_wip.o fdt_rw.o fdt_sw.o fdt_strerror.o

lib/net_utils.c

@@ -0,0 +1,26 @@
+#include <linux/string.h>
+#include <linux/if_ether.h>
+#include <linux/ctype.h>
+#include <linux/kernel.h>
+
+int mac_pton(const char *s, u8 *mac)
+{
+	int i;
+
+	/* XX:XX:XX:XX:XX:XX */
+	if (strlen(s) < 3 * ETH_ALEN - 1)
+		return 0;
+
+	/* 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 0;
+		if (i != ETH_ALEN - 1 && s[i * 3 + 2] != ':')
+			return 0;
+	}
+	for (i = 0; i < ETH_ALEN; i++) {
+		mac[i] = (hex_to_bin(s[i * 3]) << 4) | hex_to_bin(s[i * 3 + 1]);
+	}
+	return 1;
+}
+EXPORT_SYMBOL(mac_pton);