ip/ipprefix.c

   1 /*
   2  * Copyright (C)2005 USAGI/WIDE Project
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation; either version 2 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  17  */
  18 /*
  19  * based on ip.c, iproute.c
  20  */
  21 /*
  22  * Authors:
  23  *      Masahide NAKAMURA @USAGI
  24  */
  25
  26 #include <stdio.h>
  27 #include <stdlib.h>
  28 #include <string.h>
  29 #include <netinet/icmp6.h>
  30 #include "utils.h"
  31
  32 /* prefix flags; see kernel's net/ipv6/addrconf.c and include/net/if_inet6.h */
  33 #define IF_PREFIX_ONLINK        0x01
  34 #define IF_PREFIX_AUTOCONF      0x02
  35
  36 int print_prefix(const struct sockaddr_nl *who, struct nlmsghdr *n, void *arg)
  37 {
  38         FILE *fp = (FILE*)arg;
  39         struct prefixmsg *prefix = NLMSG_DATA(n);
  40         int len = n->nlmsg_len;
  41         struct rtattr * tb[RTA_MAX+1];
  42         int family = preferred_family;
  43
  44         if (n->nlmsg_type != RTM_NEWPREFIX) {
  45                 fprintf(stderr, "Not a prefix: %08x %08x %08x\n",
  46                         n->nlmsg_len, n->nlmsg_type, n->nlmsg_flags);
  47                 return 0;
  48         }
  49
  50         len -= NLMSG_LENGTH(sizeof(*prefix));
  51         if (len < 0) {
  52                 fprintf(stderr, "BUG: wrong nlmsg len %d\n", len);
  53                 return -1;
  54         }
  55
  56         if (family == AF_UNSPEC)
  57                 family = AF_INET6;
  58         if (family != AF_INET6)
  59                 return 0;
  60
  61         if (prefix->prefix_family != AF_INET6) {
  62                 fprintf(stderr, "wrong family %d\n", prefix->prefix_family);
  63                 return 0;
  64         }
  65         if (prefix->prefix_type != ND_OPT_PREFIX_INFORMATION) {
  66                 fprintf(stderr, "wrong ND type %d\n", prefix->prefix_type);
  67                 return 0;
  68         }
  69
  70         parse_rtattr(tb, RTA_MAX, RTM_RTA(prefix), len);
  71
  72         fprintf(fp, "prefix ");
  73
  74         if (tb[PREFIX_ADDRESS]) {
  75                 struct in6_addr *pfx;
  76                 char abuf[256];
  77
  78                 pfx = (struct in6_addr *)RTA_DATA(tb[PREFIX_ADDRESS]);
  79
  80                 memset(abuf, '\0', sizeof(abuf));
  81                 fprintf(fp, "%s", rt_addr_n2a(family, sizeof(*pfx), pfx,
  82                                               abuf, sizeof(abuf)));
  83         }
  84         fprintf(fp, "/%u ", prefix->prefix_len);
  85
  86         fprintf(fp, "dev %s ", ll_index_to_name(prefix->prefix_ifindex));
  87
  88         if (prefix->prefix_flags & IF_PREFIX_ONLINK)
  89                 fprintf(fp, "onlink ");
  90         if (prefix->prefix_flags & IF_PREFIX_AUTOCONF)
  91                 fprintf(fp, "autoconf ");
  92
  93         if (tb[PREFIX_CACHEINFO]) {
  94                 struct prefix_cacheinfo *pc;
  95                 pc = (struct prefix_cacheinfo *)tb[PREFIX_CACHEINFO];
  96
  97                 fprintf(fp, "valid %u ", pc->valid_time);
  98                 fprintf(fp, "preferred %u ", pc->preferred_time);
  99         }
 100
 101         fprintf(fp, "\n");
 102         fflush(fp);
 103
 104         return 0;
 105 }
 106