src/nl-route-get.c

   1 /*
   2  * src/nl-route-get.c     Get Route Attributes
   3  *
   4  *      This library is free software; you can redistribute it and/or
   5  *      modify it under the terms of the GNU Lesser General Public
   6  *      License as published by the Free Software Foundation version 2.1
   7  *      of the License.
   8  *
   9  * Copyright (c) 2003-2006 Thomas Graf <tgraf@suug.ch>
  10  */
  11
  12 #include "utils.h"
  13
  14 static void print_usage(void)
  15 {
  16         printf("Usage: nl-route-get <addr>\n");
  17         exit(1);
  18 }
  19
  20 static int cb(struct nl_msg *msg, void *arg)
  21 {
  22         nl_cache_parse_and_add(arg, msg);
  23
  24         return 0;
  25 }
  26
  27 int main(int argc, char *argv[])
  28 {
  29         struct nl_handle *nlh;
  30         struct nl_cache *link_cache, *route_cache;
  31         struct nl_addr *dst;
  32         struct nl_dump_params params = {
  33                 .dp_fd = stdout,
  34                 .dp_type = NL_DUMP_BRIEF
  35         };
  36         int err = 1;
  37
  38         if (argc < 2 || !strcmp(argv[1], "-h"))
  39                 print_usage();
  40
  41         if (nltool_init(argc, argv) < 0)
  42                 goto errout;
  43
  44         nlh = nl_handle_alloc_nondefault(nltool_cbset);
  45         if (!nlh)
  46                 goto errout;
  47
  48         if (nltool_connect(nlh, NETLINK_ROUTE) < 0)
  49                 goto errout_free_handle;
  50
  51         link_cache = nltool_alloc_link_cache(nlh);
  52         if (!link_cache)
  53                 goto errout_close;
  54
  55         dst = nltool_addr_parse(argv[1]);
  56         if (!dst)
  57                 goto errout_link_cache;
  58
  59         route_cache = nltool_alloc_route_cache(nlh);
  60         if (!route_cache)
  61                 goto errout_addr_put;
  62
  63         {
  64                 struct nl_msg *m;
  65                 struct rtmsg rmsg = {
  66                         .rtm_family = nl_addr_get_family(dst),
  67                         .rtm_dst_len = nl_addr_get_prefixlen(dst),
  68                 };
  69
  70                 m = nlmsg_build_simple(RTM_GETROUTE, 0);
  71                 nlmsg_append(m, &rmsg, sizeof(rmsg), 1);
  72                 nla_put_addr(m, RTA_DST, dst);
  73
  74                 if ((err = nl_send_auto_complete(nlh, m)) < 0) {
  75                         nlmsg_free(m);
  76                         fprintf(stderr, "%s\n", nl_geterror());
  77                         goto errout_route_cache;
  78                 }
  79
  80                 nlmsg_free(m);
  81
  82                 nl_cb_set(nl_handle_get_cb(nlh), NL_CB_VALID, NL_CB_CUSTOM,
  83                           cb, route_cache);
  84
  85                 if (nl_recvmsgs_def(nlh) < 0) {
  86                         fprintf(stderr, "%s\n", nl_geterror());
  87                         goto errout_route_cache;
  88                 }
  89         }
  90
  91         nl_cache_dump(route_cache, &params);
  92
  93         err = 0;
  94 errout_route_cache:
  95         nl_cache_free(route_cache);
  96 errout_addr_put:
  97         nl_addr_put(dst);
  98 errout_link_cache:
  99         nl_cache_free(link_cache);
 100 errout_close:
 101         nl_close(nlh);
 102 errout_free_handle:
 103         nl_handle_destroy(nlh);
 104 errout:
 105         return err;
 106 }