mono/metadata/mono-route.c

   1 /**
   2  * \file
   3  * Read the network routing tables using sysctl(3) calls
   4  * Required for Unix-like systems that don't have Linux's /proc/net/route
   5  *
   6  * Author:
   7  *   Ben Woods (woodsb02@gmail.com)
   8  */
   9
  10 #include "config.h"
  11
  12 #if HOST_DARWIN || HOST_BSD
  13
  14 #include <sys/types.h>
  15 #include <sys/socket.h>
  16 #include <net/if.h>
  17 #include <net/if_dl.h>
  18 #include <netinet/in.h>
  19 #include <sys/param.h>
  20 #include <sys/sysctl.h>
  21 #include <stdlib.h>
  22 #include <string.h>
  23
  24 #if HOST_IOS || HOST_WATCHOS || HOST_TVOS
  25 // The iOS SDK does not provide the net/route.h header but using the Darwin version works fine.
  26 #include "../../support/ios/net/route.h"
  27 #else
  28 #include <net/route.h>
  29 #endif
  30
  31 static in_addr_t
  32 gateway_from_rtm (struct rt_msghdr *rtm);
  33
  34 #include "object.h"
  35 #include "icall-decl.h"
  36
  37 MonoBoolean
  38 ves_icall_System_Net_NetworkInformation_MacOsIPInterfaceProperties_ParseRouteInfo (MonoStringHandle iface_handle, MonoArrayHandleOut gw_addr_list_handle, MonoError *error)
  39 {
  40         MonoString *iface = MONO_HANDLE_RAW (iface_handle);
  41         MONO_HANDLE_ASSIGN_RAW (gw_addr_list_handle, NULL);
  42
  43         size_t needed;
  44         in_addr_t in;
  45         int mib [6];
  46         int num_gws = 0, gwnum = 0;
  47         unsigned int ifindex = 0;
  48         char *buf = NULL;
  49         char *next, *lim;
  50         char *ifacename = NULL;
  51         struct rt_msghdr *rtm;
  52         MonoArray *gw_addr_list = NULL;
  53         MonoStringHandle addr_string_handle = NULL_HANDLE_INIT; // FIXME probably overkill
  54         MonoDomain *domain = mono_domain_get ();
  55         MonoBoolean result = FALSE;
  56
  57         ifacename = mono_string_to_utf8_checked_internal (iface, error);
  58         goto_if_nok (error, fail);
  59
  60         if ((ifindex = if_nametoindex (ifacename)) == 0)
  61                 goto fail;
  62
  63         // MIB array defining data to read from sysctl
  64         mib [0] = CTL_NET;      // Networking
  65         mib [1] = PF_ROUTE;     // Routing messages
  66         mib [2] = 0;            // Protocol number (always zero)
  67         mib [3] = AF_INET;      // Address family (IPv4)
  68         mib [4] = NET_RT_DUMP;  // Dump routing table
  69         mib [5] = 0;            //
  70
  71         // First sysctl call with oldp set to NULL to determine size of available data
  72         if (sysctl(mib, G_N_ELEMENTS(mib), NULL, &needed, NULL, 0) < 0)
  73                 goto fail;
  74
  75         // Allocate suffcient memory for available data based on the previous sysctl call
  76         if ((buf = g_malloc (needed)) == NULL)
  77                 goto fail;
  78
  79         // Second sysctl call to retrieve data into appropriately sized buffer
  80         if (sysctl (mib, G_N_ELEMENTS (mib), buf, &needed, NULL, 0) < 0)
  81                 goto fail;
  82
  83         lim = buf + needed;
  84         for (next = buf; next < lim; next += rtm->rtm_msglen) {
  85                 rtm = (struct rt_msghdr *)next;
  86                 if (rtm->rtm_version != RTM_VERSION
  87                         || rtm->rtm_index != ifindex
  88                         || (in = gateway_from_rtm (rtm)) == 0)
  89                         continue;
  90                 num_gws++;
  91         }
  92
  93         gw_addr_list = mono_array_new_checked (domain, mono_get_string_class (), num_gws, error);
  94         goto_if_nok (error, leave);
  95
  96         MONO_HANDLE_ASSIGN_RAW (gw_addr_list_handle, gw_addr_list);
  97
  98         addr_string_handle = MONO_HANDLE_NEW (MonoString, NULL); // FIXME probably overkill
  99
 100         for (next = buf; next < lim; next += rtm->rtm_msglen) {
 101                 rtm = (struct rt_msghdr *)next;
 102                 if (rtm->rtm_version != RTM_VERSION
 103                         || rtm->rtm_index != ifindex
 104                         || (in = gateway_from_rtm (rtm)) == 0)
 105                         continue;
 106
 107                 MonoString *addr_string;
 108                 char addr [16], *ptr;
 109                 int len;
 110
 111                 ptr = (char *) &in;
 112                 len = snprintf(addr, sizeof (addr), "%u.%u.%u.%u",
 113                         (unsigned char) ptr [0],
 114                         (unsigned char) ptr [1],
 115                         (unsigned char) ptr [2],
 116                         (unsigned char) ptr [3]);
 117
 118                 if (len >= sizeof (addr) || len < 0)
 119                         // snprintf output truncated
 120                         continue;
 121
 122                 addr_string = mono_string_new_checked (domain, addr, error);
 123                 goto_if_nok (error, leave);
 124                 MONO_HANDLE_ASSIGN_RAW (addr_string_handle, addr_string); // FIXME probably overkill
 125                 mono_array_setref_internal (gw_addr_list, gwnum, addr_string);
 126                 gwnum++;
 127         }
 128 leave:
 129         result = is_ok (error);
 130 fail:
 131         g_free (ifacename);
 132         g_free (buf);
 133         return result;
 134 }
 135
 136 static in_addr_t
 137 gateway_from_rtm(struct rt_msghdr *rtm)
 138 {
 139         struct sockaddr *gw;
 140         unsigned int l;
 141
 142         struct sockaddr *addr = (struct sockaddr *)(rtm + 1);
 143         l = roundup(addr->sa_len, sizeof(long)); \
 144         gw = (struct sockaddr *)((char *) addr + l); \
 145
 146         if (rtm->rtm_addrs & RTA_GATEWAY) {
 147                 if(gw->sa_family == AF_INET) {
 148                         struct sockaddr_in *sockin = (struct sockaddr_in *)gw;
 149                         return(sockin->sin_addr.s_addr);
 150                 }
 151         }
 152
 153         return 0;
 154 }
 155
 156 #else
 157
 158 #include "object.h"
 159 #include "icall-decl.h"
 160
 161 MonoBoolean
 162 ves_icall_System_Net_NetworkInformation_MacOsIPInterfaceProperties_ParseRouteInfo (MonoStringHandle iface_handle, MonoArrayHandleOut gw_addr_list_handle, MonoError *error)
 163 {
 164         mono_error_set_not_implemented (error, "");
 165         return FALSE;
 166 }
 167
 168 #endif
 169
 170
 171 extern const char mono_route_empty_file_no_warning;
 172 const char mono_route_empty_file_no_warning = 0;