xref: /linux/lib/net_utils.c (revision 0c7c237b1c35011ef0b8d30c1d5c20bc6ae7b69b)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/string.h>
3 #include <linux/if_ether.h>
4 #include <linux/ctype.h>
5 #include <linux/export.h>
6 #include <linux/hex.h>
7 
8 bool mac_pton(const char *s, u8 *mac)
9 {
10 	size_t maxlen = 3 * ETH_ALEN - 1;
11 	int i;
12 
13 	/* XX:XX:XX:XX:XX:XX */
14 	if (strnlen(s, maxlen) < maxlen)
15 		return false;
16 
17 	/* Don't dirty result unless string is valid MAC. */
18 	for (i = 0; i < ETH_ALEN; i++) {
19 		if (!isxdigit(s[i * 3]) || !isxdigit(s[i * 3 + 1]))
20 			return false;
21 		if (i != ETH_ALEN - 1 && s[i * 3 + 2] != ':')
22 			return false;
23 	}
24 	for (i = 0; i < ETH_ALEN; i++) {
25 		mac[i] = (hex_to_bin(s[i * 3]) << 4) | hex_to_bin(s[i * 3 + 1]);
26 	}
27 	return true;
28 }
29 EXPORT_SYMBOL(mac_pton);
30