src/servers/net/AutoconfigLooper.cpp

   1 /*
   2  * Copyright 2006-2012, Haiku, Inc. All Rights Reserved.
   3  * Distributed under the terms of the MIT License.
   4  *
   5  * Authors:
   6  *              Axel Dörfler, axeld@pinc-software.de
   7  *              Alexander von Gluck, kallisti5@unixzen.com
   8  */
   9
  10
  11 #include "AutoconfigLooper.h"
  12
  13 #include <errno.h>
  14 #include <net/if_dl.h>
  15 #include <net/if_media.h>
  16 #include <net/if_types.h>
  17 #include <stdio.h>
  18 #include <sys/socket.h>
  19 #include <sys/sockio.h>
  20
  21 #include <NetworkInterface.h>
  22 #include <NetworkNotifications.h>
  23
  24 #include "DHCPClient.h"
  25 #include "NetServer.h"
  26
  27
  28 static const uint32 kMsgReadyToRun = 'rdyr';
  29
  30
  31 AutoconfigLooper::AutoconfigLooper(BMessenger target, const char* device)
  32         : BLooper(device),
  33         fTarget(target),
  34         fDevice(device),
  35         fCurrentClient(NULL),
  36         fLastMediaStatus(0),
  37         fJoiningNetwork(false)
  38 {
  39         BMessage ready(kMsgReadyToRun);
  40         PostMessage(&ready);
  41 }
  42
  43
  44 AutoconfigLooper::~AutoconfigLooper()
  45 {
  46 }
  47
  48
  49 void
  50 AutoconfigLooper::_RemoveClient()
  51 {
  52         if (fCurrentClient == NULL)
  53                 return;
  54
  55         RemoveHandler(fCurrentClient);
  56         delete fCurrentClient;
  57         fCurrentClient = NULL;
  58 }
  59
  60
  61 void
  62 AutoconfigLooper::_ConfigureIPv4()
  63 {
  64         // start with DHCP
  65
  66         if (fCurrentClient == NULL) {
  67                 fCurrentClient = new DHCPClient(fTarget, fDevice.String());
  68                 AddHandler(fCurrentClient);
  69         }
  70
  71         // set IFF_CONFIGURING flag on interface
  72
  73         BNetworkInterface interface(fDevice.String());
  74         int32 flags = interface.Flags() & ~IFF_AUTO_CONFIGURED;
  75         interface.SetFlags(flags | IFF_CONFIGURING);
  76
  77         if (fCurrentClient->Initialize() == B_OK)
  78                 return;
  79
  80         _RemoveClient();
  81
  82         puts("DHCP failed miserably!");
  83
  84         // DHCP obviously didn't work out, take some default values for now
  85         // TODO: have a look at zeroconf
  86         // TODO: this could also be done add-on based
  87
  88         if ((interface.Flags() & IFF_CONFIGURING) == 0) {
  89                 // Someone else configured the interface in the mean time
  90                 return;
  91         }
  92
  93         BMessage message(kMsgConfigureInterface);
  94         message.AddString("device", fDevice.String());
  95         message.AddBool("auto_configured", true);
  96
  97         BNetworkAddress link;
  98         uint8 last = 56;
  99         if (interface.GetHardwareAddress(link) == B_OK) {
 100                 // choose IP address depending on the MAC address, if available
 101                 uint8* mac = link.LinkLevelAddress();
 102                 last = mac[0] ^ mac[1] ^ mac[2] ^ mac[3] ^ mac[4] ^ mac[5];
 103                 if (last > 253)
 104                         last = 253;
 105                 else if (last == 0)
 106                         last = 1;
 107         }
 108
 109         // IANA defined the default autoconfig network (for when a DHCP request
 110         // fails for some reason) as being 169.254.0.0/255.255.0.0. We are only
 111         // generating the last octet but we could also use the 2 last octets if
 112         // wanted.
 113         char string[64];
 114         snprintf(string, sizeof(string), "169.254.0.%u", last);
 115
 116         BMessage address;
 117         address.AddInt32("family", AF_INET);
 118         address.AddString("address", string);
 119         message.AddMessage("address", &address);
 120
 121         fTarget.SendMessage(&message);
 122 }
 123
 124
 125 void
 126 AutoconfigLooper::_ReadyToRun()
 127 {
 128         start_watching_network(
 129                 B_WATCH_NETWORK_LINK_CHANGES | B_WATCH_NETWORK_WLAN_CHANGES, this);
 130
 131         BNetworkInterface interface(fDevice.String());
 132         if (interface.HasLink()) {
 133                 _ConfigureIPv4();
 134                 //_ConfigureIPv6();     // TODO: router advertisement and dhcpv6
 135
 136                 // Also make sure we don't spuriously try to configure again from
 137                 // a link changed notification that might race us.
 138                 fLastMediaStatus |= IFM_ACTIVE;
 139         }
 140 }
 141
 142
 143 void
 144 AutoconfigLooper::_NetworkMonitorNotification(BMessage* message)
 145 {
 146         int32 opcode;
 147         BString device;
 148         if (message->FindString("device", &device) != B_OK) {
 149                 if (message->FindString("interface", &device) != B_OK)
 150                         return;
 151
 152                 // TODO: Clean this mess up. Wireless devices currently use their
 153                 // "device_name" in the interface field. First of all the
 154                 // joins/leaves/scans should be device, not interface specific, so
 155                 // the field should be changed. Then the device_name as seen by the
 156                 // driver is missing the "/dev" part, as it is a relative path within
 157                 // "/dev". On the other hand the net stack uses names that include
 158                 // "/dev" as it uses them to open the fds, hence a full absolute path.
 159                 // Note that the wpa_supplicant does the same workaround as we do here
 160                 // to build an interface name, so that has to be changed as well when
 161                 // this is fixed.
 162                 device.Prepend("/dev/");
 163         }
 164
 165         if (device != fDevice || message->FindInt32("opcode", &opcode) != B_OK)
 166                 return;
 167
 168         switch (opcode) {
 169                 case B_NETWORK_DEVICE_LINK_CHANGED:
 170                 {
 171                         int32 media;
 172                         if (message->FindInt32("media", &media) != B_OK)
 173                                 break;
 174
 175                         if ((fLastMediaStatus & IFM_ACTIVE) == 0
 176                                 && (media & IFM_ACTIVE) != 0) {
 177                                 // Reconfigure the interface when we have a link again
 178                                 _ConfigureIPv4();
 179                                 //_ConfigureIPv6();     // TODO: router advertisement and dhcpv6
 180                         }
 181
 182                         fLastMediaStatus = media;
 183                         break;
 184                 }
 185
 186                 case B_NETWORK_WLAN_SCANNED:
 187                 {
 188                         if (fJoiningNetwork || (fLastMediaStatus & IFM_ACTIVE) != 0) {
 189                                 // We already have a link or are already joining.
 190                                 break;
 191                         }
 192
 193                         fJoiningNetwork = true;
 194                                 // TODO: For now we never reset this flag. We can only do that
 195                                 // after infrastructure has been added to discern a scan reason.
 196                                 // If we would always auto join we would possibly interfere
 197                                 // with active scans in the process of connecting to an AP
 198                                 // either for the initial connection, or after connection loss
 199                                 // to re-establish the link.
 200
 201                         BMessage message(kMsgAutoJoinNetwork);
 202                         message.AddString("device", fDevice);
 203                         fTarget.SendMessage(&message);
 204                         break;
 205                 }
 206         }
 207 }
 208
 209
 210 void
 211 AutoconfigLooper::MessageReceived(BMessage* message)
 212 {
 213         switch (message->what) {
 214                 case kMsgReadyToRun:
 215                         _ReadyToRun();
 216                         break;
 217
 218                 case B_NETWORK_MONITOR:
 219                         _NetworkMonitorNotification(message);
 220                         break;
 221
 222                 default:
 223                         BLooper::MessageReceived(message);
 224                         break;
 225         }
 226 }
 227