busybox/networking/libiproute/ll_map.c

   1 /*
   2  * ll_map.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
  13 #include <stdio.h>
  14 #include <string.h>
  15 #include <stdlib.h>
  16 #include <netinet/in.h>
  17
  18 #include "libnetlink.h"
  19
  20 struct idxmap
  21 {
  22         struct idxmap * next;
  23         int             index;
  24         int             type;
  25         int             alen;
  26         unsigned        flags;
  27         unsigned char   addr[8];
  28         char            name[16];
  29 };
  30
  31 static struct idxmap *idxmap[16];
  32
  33 int ll_remember_index(struct sockaddr_nl *who, struct nlmsghdr *n, void *arg)
  34 {
  35         int h;
  36         struct ifinfomsg *ifi = NLMSG_DATA(n);
  37         struct idxmap *im, **imp;
  38         struct rtattr *tb[IFLA_MAX+1];
  39
  40         if (n->nlmsg_type != RTM_NEWLINK)
  41                 return 0;
  42
  43         if (n->nlmsg_len < NLMSG_LENGTH(sizeof(ifi)))
  44                 return -1;
  45
  46
  47         memset(tb, 0, sizeof(tb));
  48         parse_rtattr(tb, IFLA_MAX, IFLA_RTA(ifi), IFLA_PAYLOAD(n));
  49         if (tb[IFLA_IFNAME] == NULL)
  50                 return 0;
  51
  52         h = ifi->ifi_index&0xF;
  53
  54         for (imp=&idxmap[h]; (im=*imp)!=NULL; imp = &im->next)
  55                 if (im->index == ifi->ifi_index)
  56                         break;
  57
  58         if (im == NULL) {
  59                 im = malloc(sizeof(*im));
  60                 if (im == NULL)
  61                         return 0;
  62                 im->next = *imp;
  63                 im->index = ifi->ifi_index;
  64                 *imp = im;
  65         }
  66
  67         im->type = ifi->ifi_type;
  68         im->flags = ifi->ifi_flags;
  69         if (tb[IFLA_ADDRESS]) {
  70                 int alen;
  71                 im->alen = alen = RTA_PAYLOAD(tb[IFLA_ADDRESS]);
  72                 if (alen > sizeof(im->addr))
  73                         alen = sizeof(im->addr);
  74                 memcpy(im->addr, RTA_DATA(tb[IFLA_ADDRESS]), alen);
  75         } else {
  76                 im->alen = 0;
  77                 memset(im->addr, 0, sizeof(im->addr));
  78         }
  79         strcpy(im->name, RTA_DATA(tb[IFLA_IFNAME]));
  80         return 0;
  81 }
  82
  83 const char *ll_idx_n2a(int idx, char *buf)
  84 {
  85         struct idxmap *im;
  86
  87         if (idx == 0)
  88                 return "*";
  89         for (im = idxmap[idx&0xF]; im; im = im->next)
  90                 if (im->index == idx)
  91                         return im->name;
  92         snprintf(buf, 16, "if%d", idx);
  93         return buf;
  94 }
  95
  96
  97 const char *ll_index_to_name(int idx)
  98 {
  99         static char nbuf[16];
 100
 101         return ll_idx_n2a(idx, nbuf);
 102 }
 103
 104 int ll_index_to_type(int idx)
 105 {
 106         struct idxmap *im;
 107
 108         if (idx == 0)
 109                 return -1;
 110         for (im = idxmap[idx&0xF]; im; im = im->next)
 111                 if (im->index == idx)
 112                         return im->type;
 113         return -1;
 114 }
 115
 116 unsigned ll_index_to_flags(int idx)
 117 {
 118         struct idxmap *im;
 119
 120         if (idx == 0)
 121                 return 0;
 122
 123         for (im = idxmap[idx&0xF]; im; im = im->next)
 124                 if (im->index == idx)
 125                         return im->flags;
 126         return 0;
 127 }
 128
 129 int ll_name_to_index(char *name)
 130 {
 131         static char ncache[16];
 132         static int icache;
 133         struct idxmap *im;
 134         int i;
 135
 136         if (name == NULL)
 137                 return 0;
 138         if (icache && strcmp(name, ncache) == 0)
 139                 return icache;
 140         for (i=0; i<16; i++) {
 141                 for (im = idxmap[i]; im; im = im->next) {
 142                         if (strcmp(im->name, name) == 0) {
 143                                 icache = im->index;
 144                                 strcpy(ncache, name);
 145                                 return im->index;
 146                         }
 147                 }
 148         }
 149         return 0;
 150 }
 151
 152 int ll_init_map(struct rtnl_handle *rth)
 153 {
 154         if (rtnl_wilddump_request(rth, AF_UNSPEC, RTM_GETLINK) < 0) {
 155                 perror("Cannot send dump request");
 156                 exit(1);
 157         }
 158
 159         if (rtnl_dump_filter(rth, ll_remember_index, &idxmap, NULL, NULL) < 0) {
 160                 fprintf(stderr, "Dump terminated\n");
 161                 exit(1);
 162         }
 163         return 0;
 164 }