lib/ll_addr.c

   1 /*
   2  * ll_addr.c
   3  *
   4  *              This program is free software; you can redistribute it and/or
   5  *              modify it under the terms of the GNU General Public License
   6  *              as published by the Free Software Foundation; either version
   7  *              2 of the License, or (at your option) any later version.
   8  *
   9  * Authors:     Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
  10  */
  11
  12 #include <stdio.h>
  13 #include <stdlib.h>
  14 #include <unistd.h>
  15 #include <fcntl.h>
  16 #include <sys/ioctl.h>
  17 #include <sys/socket.h>
  18 #include <netinet/in.h>
  19 #include <arpa/inet.h>
  20 #include <string.h>
  21
  22 #include <linux/netdevice.h>
  23 #include <linux/if_arp.h>
  24 #include <linux/sockios.h>
  25
  26 #include "rt_names.h"
  27 #include "utils.h"
  28
  29 const char *ll_addr_n2a(const unsigned char *addr, int alen, int type,
  30                         char *buf, int blen)
  31 {
  32         int i;
  33         int l;
  34
  35         if (alen == 4 &&
  36             (type == ARPHRD_TUNNEL || type == ARPHRD_SIT
  37              || type == ARPHRD_IPGRE))
  38                 return inet_ntop(AF_INET, addr, buf, blen);
  39
  40         if (alen == 16 && (type == ARPHRD_TUNNEL6 || type == ARPHRD_IP6GRE))
  41                 return inet_ntop(AF_INET6, addr, buf, blen);
  42
  43         snprintf(buf, blen, "%02x", addr[0]);
  44         for (i = 1, l = 2; i < alen && l < blen; i++, l += 3)
  45                 snprintf(buf + l, blen - l, ":%02x", addr[i]);
  46         return buf;
  47 }
  48
  49 /*NB: lladdr is char * (rather than u8 *) because sa_data is char * (1003.1g) */
  50 int ll_addr_a2n(char *lladdr, int len, const char *arg)
  51 {
  52         if (strchr(arg, '.')) {
  53                 inet_prefix pfx;
  54                 if (get_addr_1(&pfx, arg, AF_INET)) {
  55                         fprintf(stderr, "\"%s\" is invalid lladdr.\n", arg);
  56                         return -1;
  57                 }
  58                 if (len < 4)
  59                         return -1;
  60                 memcpy(lladdr, pfx.data, 4);
  61                 return 4;
  62         } else {
  63                 int i;
  64
  65                 for (i = 0; i < len; i++) {
  66                         int temp;
  67                         char *cp = strchr(arg, ':');
  68                         if (cp) {
  69                                 *cp = 0;
  70                                 cp++;
  71                         }
  72                         if (sscanf(arg, "%x", &temp) != 1) {
  73                                 fprintf(stderr, "\"%s\" is invalid lladdr.\n",
  74                                         arg);
  75                                 return -1;
  76                         }
  77                         if (temp < 0 || temp > 255) {
  78                                 fprintf(stderr, "\"%s\" is invalid lladdr.\n",
  79                                         arg);
  80                                 return -1;
  81                         }
  82                         lladdr[i] = temp;
  83                         if (!cp)
  84                                 break;
  85                         arg = cp;
  86                 }
  87                 return i + 1;
  88         }
  89 }