libs/luanet/src/bridge.c

   1 /*
   2  *  Licensed under the Apache License, Version 2.0 (the "License");
   3  *  you may not use this file except in compliance with the License.
   4  *  You may obtain a copy of the License at
   5  *
   6  *      http://www.apache.org/licenses/LICENSE-2.0
   7  *
   8  *  Unless required by applicable law or agreed to in writing, software
   9  *  distributed under the License is distributed on an "AS IS" BASIS,
  10  *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  11  *  See the License for the specific language governing permissions and
  12  *  limitations under the License.
  13  *
  14  *   Copyright (C) 2008 John Crispin <blogic@openwrt.org>
  15  *   Copyright (C) 2008 Steven Barth <steven@midlink.org>
  16  */
  17
  18 #include <string.h>
  19 #include <net/if.h>
  20 #include <linux/sockios.h>
  21 #include <dirent.h>
  22 #include <sys/types.h>
  23 #include <sys/stat.h>
  24 #include <sys/ioctl.h>
  25 #include <unistd.h>
  26 #include <stdio.h>
  27 #include <stdlib.h>
  28
  29 #include <lua.h>
  30 #include <lualib.h>
  31 #include <lauxlib.h>
  32
  33 static int sock_bridge = 0;
  34 int bridge_startup()
  35 {
  36         if(!sock_bridge)
  37                 sock_bridge = socket(AF_LOCAL, SOCK_STREAM, 0);
  38         return sock_bridge;
  39 }
  40
  41 void bridge_shutdown(void)
  42 {
  43         if(!sock_bridge)
  44                 return;
  45         close(sock_bridge);
  46         sock_bridge = 0;
  47 }
  48
  49 static inline int _bridge_new(lua_State *L, int i)
  50 {
  51         char *ifname;
  52         if(lua_gettop(L) != 1)
  53         {
  54                 lua_pushstring(L, "invalid arg list");
  55                 lua_error(L);
  56                 return 0;
  57         }
  58
  59         ifname = (char *)lua_tostring (L, 1);
  60         if(!ioctl(sock_bridge, i, ifname))
  61                 lua_pushboolean(L, 1);
  62         else
  63                 lua_pushboolean(L, 0);
  64         return 1;
  65 }
  66
  67 int bridge_new(lua_State *L)
  68 {
  69         return _bridge_new(L, SIOCBRADDBR);
  70 }
  71
  72 int bridge_del(lua_State *L)
  73 {
  74         return _bridge_new(L, SIOCBRDELBR);
  75 }
  76
  77 static inline int _bridge_addif(lua_State *L, int i)
  78 {
  79         struct ifreq ifr;
  80         char *br, *ifname;
  81         if(lua_gettop(L) != 2)
  82         {
  83                 lua_pushstring(L, "invalid arg list");
  84                 lua_error(L);
  85                 return 0;
  86         }
  87         br = (char *)lua_tostring (L, 1);
  88         ifname = (char *)lua_tostring (L, 2);
  89         strncpy(ifr.ifr_name, br, IFNAMSIZ);
  90         ifr.ifr_ifindex = if_nametoindex(ifname);
  91         if(ifr.ifr_ifindex == 0)
  92         {
  93                 lua_pushboolean(L, 0);
  94                 return 1;
  95         }
  96         if(!ioctl(sock_bridge, i, &ifr))
  97                 lua_pushboolean(L, 1);
  98         else
  99                 lua_pushboolean(L, 0);
 100         return 1;
 101 }
 102
 103 int bridge_addif(lua_State *L)
 104 {
 105         return _bridge_addif(L, SIOCBRADDIF);
 106 }
 107
 108 int bridge_delif(lua_State *L)
 109 {
 110         return _bridge_addif(L, SIOCBRDELIF);
 111 }
 112
 113 #define SYSFS_PATH_MAX  512
 114 #define SYSFS_CLASS_NET "/sys/class/net/"
 115 static int isbridge(const struct dirent *entry)
 116 {
 117         char path[SYSFS_PATH_MAX];
 118         struct stat st;
 119
 120         snprintf(path, SYSFS_PATH_MAX, SYSFS_CLASS_NET "%s/bridge", entry->d_name);
 121         return stat(path, &st) == 0 && S_ISDIR(st.st_mode);
 122 }
 123
 124 static int isdev(const struct dirent *entry)
 125 {
 126         if(*entry->d_name == '.')
 127                 return 0;
 128         return 1;
 129 }
 130
 131 static inline void bridge_getifs(lua_State *L, const char *ifname)
 132 {
 133         struct dirent **namelist;
 134         int i, count = 0;
 135         char path[SYSFS_PATH_MAX];
 136         snprintf(path, SYSFS_PATH_MAX, SYSFS_CLASS_NET "%s/brif", ifname);
 137         count = scandir(path, &namelist, isdev, alphasort);
 138         if(count < 0)
 139                 return;
 140
 141         for(i = 0; i < count; i++)
 142         {
 143                 lua_pushinteger(L, i + 1);
 144                 lua_pushstring(L, namelist[i]->d_name);
 145                 lua_settable(L, -3);
 146                 free(namelist[i]);
 147         }
 148         free(namelist);
 149         return;
 150 }
 151
 152 int bridge_getall(lua_State *L)
 153 {
 154         struct dirent **namelist;
 155         int i, count = 0;
 156         count = scandir(SYSFS_CLASS_NET, &namelist, isbridge, alphasort);
 157         if (count < 0)
 158                 return 0;
 159
 160         lua_newtable(L);
 161         for (i = 0; i < count; i++)
 162         {
 163                 lua_pushstring(L, namelist[i]->d_name);
 164                 lua_newtable(L);
 165                 bridge_getifs(L, namelist[i]->d_name);
 166                 free(namelist[i]);
 167                 lua_settable(L, -3);
 168         }
 169         free(namelist);
 170         return 1;
 171 }