libbb/in_ether.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * Utility routines.
   4  */
   5
   6 //kbuild:lib-$(CONFIG_ARP) += in_ether.o
   7 //kbuild:lib-$(CONFIG_IFCONFIG) += in_ether.o
   8 //kbuild:lib-$(CONFIG_IFENSLAVE) += in_ether.o
   9
  10 #include "libbb.h"
  11 #include <net/if_arp.h>
  12 #include <net/ethernet.h>
  13
  14 /* Convert Ethernet address from "XX[:]XX[:]XX[:]XX[:]XX[:]XX" to sockaddr.
  15  * Return nonzero on error.
  16  */
  17 int FAST_FUNC in_ether(const char *bufp, struct sockaddr *sap)
  18 {
  19         char *ptr;
  20         int i, j;
  21         unsigned char val;
  22         unsigned char c;
  23
  24         sap->sa_family = ARPHRD_ETHER;
  25         ptr = (char *) sap->sa_data;
  26
  27         i = ETH_ALEN;
  28         goto first;
  29         do {
  30                 /* We might get a semicolon here */
  31                 if (*bufp == ':')
  32                         bufp++;
  33  first:
  34                 j = val = 0;
  35                 do {
  36                         c = *bufp;
  37                         if (((unsigned char)(c - '0')) <= 9) {
  38                                 c -= '0';
  39                         } else if ((unsigned char)((c|0x20) - 'a') <= 5) {
  40                                 c = (unsigned char)((c|0x20) - 'a') + 10;
  41                         } else {
  42                                 if (j && (c == ':' || c == '\0'))
  43                                         /* One-digit byte: __:X:__ */
  44                                         break;
  45                                 return -1;
  46                         }
  47                         ++bufp;
  48                         val <<= 4;
  49                         val += c;
  50                         j ^= 1;
  51                 } while (j);
  52
  53                 *ptr++ = val;
  54
  55         } while (--i);
  56
  57         /* Error if we aren't at end of string */
  58         return *bufp;
  59 }