ip/ipnetconf.c

   1 /*
   2  * ipnetconf.c          "ip netconf".
   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:     Nicolas Dichtel, <nicolas.dichtel@6wind.com>
  10  *
  11  */
  12
  13 #include <stdio.h>
  14 #include <stdlib.h>
  15 #include <unistd.h>
  16 #include <syslog.h>
  17 #include <fcntl.h>
  18 #include <string.h>
  19 #include <sys/time.h>
  20 #include <sys/socket.h>
  21 #include <netinet/in.h>
  22
  23 #include "rt_names.h"
  24 #include "utils.h"
  25 #include "ip_common.h"
  26
  27 static struct
  28 {
  29         int family;
  30         int ifindex;
  31 } filter;
  32
  33 static void usage(void) __attribute__((noreturn));
  34
  35 static void usage(void)
  36 {
  37         fprintf(stderr, "Usage: ip netconf show [ dev STRING ]\n");
  38         exit(-1);
  39 }
  40
  41 #define NETCONF_RTA(r)  ((struct rtattr*)(((char*)(r)) + NLMSG_ALIGN(sizeof(struct netconfmsg))))
  42
  43 int print_netconf(const struct sockaddr_nl *who, struct rtnl_ctrl_data *ctrl,
  44                   struct nlmsghdr *n, void *arg)
  45 {
  46         FILE *fp = (FILE*)arg;
  47         struct netconfmsg *ncm = NLMSG_DATA(n);
  48         int len = n->nlmsg_len;
  49         struct rtattr *tb[NETCONFA_MAX+1];
  50
  51         if (n->nlmsg_type == NLMSG_ERROR)
  52                 return -1;
  53         if (n->nlmsg_type != RTM_NEWNETCONF) {
  54                 fprintf(stderr, "Not RTM_NEWNETCONF: %08x %08x %08x\n",
  55                         n->nlmsg_len, n->nlmsg_type, n->nlmsg_flags);
  56
  57                 return -1;
  58         }
  59         len -= NLMSG_SPACE(sizeof(*ncm));
  60         if (len < 0) {
  61                 fprintf(stderr, "BUG: wrong nlmsg len %d\n", len);
  62                 return -1;
  63         }
  64
  65         if (filter.family && filter.family != ncm->ncm_family)
  66                 return 0;
  67
  68         parse_rtattr(tb, NETCONFA_MAX, NETCONF_RTA(ncm),
  69                      NLMSG_PAYLOAD(n, sizeof(*ncm)));
  70
  71         switch (ncm->ncm_family) {
  72         case AF_INET:
  73                 fprintf(fp, "ipv4 ");
  74                 break;
  75         case AF_INET6:
  76                 fprintf(fp, "ipv6 ");
  77                 break;
  78         default:
  79                 fprintf(fp, "unknown ");
  80                 break;
  81         }
  82
  83         if (tb[NETCONFA_IFINDEX]) {
  84                 int *ifindex = (int *)RTA_DATA(tb[NETCONFA_IFINDEX]);
  85
  86                 switch (*ifindex) {
  87                 case NETCONFA_IFINDEX_ALL:
  88                         fprintf(fp, "all ");
  89                         break;
  90                 case NETCONFA_IFINDEX_DEFAULT:
  91                         fprintf(fp, "default ");
  92                         break;
  93                 default:
  94                         fprintf(fp, "dev %s ", ll_index_to_name(*ifindex));
  95                         break;
  96                 }
  97         }
  98
  99         if (tb[NETCONFA_FORWARDING])
 100                 fprintf(fp, "forwarding %s ",
 101                         *(int *)RTA_DATA(tb[NETCONFA_FORWARDING])?"on":"off");
 102         if (tb[NETCONFA_RP_FILTER]) {
 103                 int rp_filter = *(int *)RTA_DATA(tb[NETCONFA_RP_FILTER]);
 104
 105                 if (rp_filter == 0)
 106                         fprintf(fp, "rp_filter off ");
 107                 else if (rp_filter == 1)
 108                         fprintf(fp, "rp_filter strict ");
 109                 else if (rp_filter == 2)
 110                         fprintf(fp, "rp_filter loose ");
 111                 else
 112                         fprintf(fp, "rp_filter unknown mode ");
 113         }
 114         if (tb[NETCONFA_MC_FORWARDING])
 115                 fprintf(fp, "mc_forwarding %d ",
 116                         *(int *)RTA_DATA(tb[NETCONFA_MC_FORWARDING]));
 117
 118         if (tb[NETCONFA_PROXY_NEIGH])
 119                 fprintf(fp, "proxy_neigh %s ",
 120                         *(int *)RTA_DATA(tb[NETCONFA_PROXY_NEIGH])?"on":"off");
 121
 122         fprintf(fp, "\n");
 123         fflush(fp);
 124         return 0;
 125 }
 126
 127 static int print_netconf2(const struct sockaddr_nl *who,
 128                           struct nlmsghdr *n, void *arg)
 129 {
 130         return print_netconf(who, NULL, n, arg);
 131 }
 132
 133 void ipnetconf_reset_filter(int ifindex)
 134 {
 135         memset(&filter, 0, sizeof(filter));
 136         filter.ifindex = ifindex;
 137 }
 138
 139 static int do_show(int argc, char **argv)
 140 {
 141         struct {
 142                 struct nlmsghdr         n;
 143                 struct netconfmsg       ncm;
 144                 char                    buf[1024];
 145         } req;
 146
 147         ipnetconf_reset_filter(0);
 148         filter.family = preferred_family;
 149         if (filter.family == AF_UNSPEC)
 150                 filter.family = AF_INET;
 151
 152         while (argc > 0) {
 153                 if (strcmp(*argv, "dev") == 0) {
 154                         NEXT_ARG();
 155                         filter.ifindex = ll_name_to_index(*argv);
 156                         if (filter.ifindex <= 0) {
 157                                 fprintf(stderr, "Device \"%s\" does not exist.\n",
 158                                         *argv);
 159                                 return -1;
 160                         }
 161                 }
 162                 argv++; argc--;
 163         }
 164
 165         ll_init_map(&rth);
 166         if (filter.ifindex) {
 167                 memset(&req, 0, sizeof(req));
 168                 req.n.nlmsg_len = NLMSG_LENGTH(sizeof(struct netconfmsg));
 169                 req.n.nlmsg_flags = NLM_F_REQUEST|NLM_F_ACK;
 170                 req.n.nlmsg_type = RTM_GETNETCONF;
 171                 req.ncm.ncm_family = filter.family;
 172                 if (filter.ifindex)
 173                         addattr_l(&req.n, sizeof(req), NETCONFA_IFINDEX,
 174                                   &filter.ifindex, sizeof(filter.ifindex));
 175
 176                 if (rtnl_send(&rth, &req.n, req.n.nlmsg_len) < 0) {
 177                         perror("Can not send request");
 178                         exit(1);
 179                 }
 180                 rtnl_listen(&rth, print_netconf, stdout);
 181         } else {
 182 dump:
 183                 if (rtnl_wilddump_request(&rth, filter.family, RTM_GETNETCONF) < 0) {
 184                         perror("Cannot send dump request");
 185                         exit(1);
 186                 }
 187                 if (rtnl_dump_filter(&rth, print_netconf2, stdout) < 0) {
 188                         fprintf(stderr, "Dump terminated\n");
 189                         exit(1);
 190                 }
 191                 if (preferred_family == AF_UNSPEC) {
 192                         preferred_family = AF_INET6;
 193                         filter.family = AF_INET6;
 194                         goto dump;
 195                 }
 196         }
 197         return 0;
 198 }
 199
 200 int do_ipnetconf(int argc, char **argv)
 201 {
 202         if (argc > 0) {
 203                 if (matches(*argv, "show") == 0 ||
 204                     matches(*argv, "lst") == 0 ||
 205                     matches(*argv, "list") == 0)
 206                         return do_show(argc-1, argv+1);
 207                 if (matches(*argv, "help") == 0)
 208                         usage();
 209         } else
 210                 return do_show(0, NULL);
 211
 212         fprintf(stderr, "Command \"%s\" is unknown, try \"ip netconf help\".\n", *argv);
 213         exit(-1);
 214 }