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 <sys/socket.h>
  30 #include <netinet/icmp6.h>
  31 #include "utils.h"
  32
  33 /* prefix flags; see kernel's net/ipv6/addrconf.c and include/net/if_inet6.h */
  34 #define IF_PREFIX_ONLINK        0x01
  35 #define IF_PREFIX_AUTOCONF      0x02
  36
  37 int print_prefix(const struct sockaddr_nl *who, struct nlmsghdr *n, void *arg)
  38 {
  39         FILE *fp = (FILE*)arg;
  40         struct prefixmsg *prefix = NLMSG_DATA(n);
  41         int len = n->nlmsg_len;
  42         struct rtattr * tb[RTA_MAX+1];
  43         int family = preferred_family;
  44
  45         if (n->nlmsg_type != RTM_NEWPREFIX) {
  46                 fprintf(stderr, "Not a prefix: %08x %08x %08x\n",
  47                         n->nlmsg_len, n->nlmsg_type, n->nlmsg_flags);
  48                 return 0;
  49         }
  50
  51         len -= NLMSG_LENGTH(sizeof(*prefix));
  52         if (len < 0) {
  53                 fprintf(stderr, "BUG: wrong nlmsg len %d\n", len);
  54                 return -1;
  55         }
  56
  57         if (family == AF_UNSPEC)
  58                 family = AF_INET6;
  59         if (family != AF_INET6)
  60                 return 0;
  61
  62         if (prefix->prefix_family != AF_INET6) {
  63                 fprintf(stderr, "incorrect protocol family: %d\n", prefix->prefix_family);
  64                 return 0;
  65         }
  66         if (prefix->prefix_type != ND_OPT_PREFIX_INFORMATION) {
  67                 fprintf(stderr, "wrong ND type %d\n", prefix->prefix_type);
  68                 return 0;
  69         }
  70
  71         parse_rtattr(tb, RTA_MAX, RTM_RTA(prefix), len);
  72
  73         fprintf(fp, "prefix ");
  74
  75         if (tb[PREFIX_ADDRESS]) {
  76                 struct in6_addr *pfx;
  77                 char abuf[256];
  78
  79                 pfx = (struct in6_addr *)RTA_DATA(tb[PREFIX_ADDRESS]);
  80
  81                 memset(abuf, '\0', sizeof(abuf));
  82                 fprintf(fp, "%s", rt_addr_n2a(family, sizeof(*pfx), pfx,
  83                                               abuf, sizeof(abuf)));
  84         }
  85         fprintf(fp, "/%u ", prefix->prefix_len);
  86
  87         fprintf(fp, "dev %s ", ll_index_to_name(prefix->prefix_ifindex));
  88
  89         if (prefix->prefix_flags & IF_PREFIX_ONLINK)
  90                 fprintf(fp, "onlink ");
  91         if (prefix->prefix_flags & IF_PREFIX_AUTOCONF)
  92                 fprintf(fp, "autoconf ");
  93
  94         if (tb[PREFIX_CACHEINFO]) {
  95                 struct prefix_cacheinfo *pc;
  96                 pc = (struct prefix_cacheinfo *)RTA_DATA(tb[PREFIX_CACHEINFO]);
  97
  98                 fprintf(fp, "valid %u ", pc->valid_time);
  99                 fprintf(fp, "preferred %u ", pc->preferred_time);
 100         }
 101
 102         fprintf(fp, "\n");
 103         fflush(fp);
 104
 105         return 0;
 106 }
 107