lib/net_utils.c

   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/kernel.h>
   6
   7 bool mac_pton(const char *s, u8 *mac)
   8 {
   9         size_t maxlen = 3 * ETH_ALEN - 1;
  10         int i;
  11
  12         /* XX:XX:XX:XX:XX:XX */
  13         if (strnlen(s, maxlen) < maxlen)
  14                 return false;
  15
  16         /* Don't dirty result unless string is valid MAC. */
  17         for (i = 0; i < ETH_ALEN; i++) {
  18                 if (!isxdigit(s[i * 3]) || !isxdigit(s[i * 3 + 1]))
  19                         return false;
  20                 if (i != ETH_ALEN - 1 && s[i * 3 + 2] != ':')
  21                         return false;
  22         }
  23         for (i = 0; i < ETH_ALEN; i++) {
  24                 mac[i] = (hex_to_bin(s[i * 3]) << 4) | hex_to_bin(s[i * 3 + 1]);
  25         }
  26         return true;
  27 }
  28 EXPORT_SYMBOL(mac_pton);