src/ip-conflict-detect.c

   1 /*
   2  * Network Configuration Module
   3  *
   4  * Copyright (c) 2000 - 2012 Samsung Electronics Co., Ltd. All rights reserved.
   5  *
   6  * Licensed under the Apache License, Version 2.0 (the "License");
   7  * you may not use this file except in compliance with the License.
   8  * You may obtain a copy of the License at
   9  *
  10  * http://www.apache.org/licenses/LICENSE-2.0
  11  *
  12  * Unless required by applicable law or agreed to in writing, software
  13  * distributed under the License is distributed on an "AS IS" BASIS,
  14  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  15  * See the License for the specific language governing permissions and
  16  * limitations under the License.
  17  *
  18  */
  19
  20 #include <stdio.h>
  21 #include <net/if.h>
  22 #include <linux/if_packet.h>
  23 #include <sys/ioctl.h>
  24 #include <sys/socket.h>
  25 #include <arpa/inet.h>
  26 #include <netinet/ether.h>
  27 #include <net/ethernet.h>
  28 #include <netinet/in.h>
  29 #include <stdlib.h>
  30 #include <stdint.h>
  31 #include <errno.h>
  32 #include <glib.h>
  33 #include <string.h>
  34 #include <unistd.h>
  35 #include <stdbool.h>
  36
  37 #include "ip-conflict-detect.h"
  38 #include "network-state.h"
  39 #include "log.h"
  40 #include "neterror.h"
  41 #include "util.h"
  42
  43 #define ARP_PACKET_SIZE 60
  44 #define MAX_SIZE_ERROR_BUFFER 256
  45 #define IP_ADDRESS_LENGTH 4
  46 #define MAC_ADDRESS_LENGTH 6
  47 #define WLAN_MAC_ADDR_MAX 20
  48 #define ARP_SOURCE_IP "0.0.0.0"
  49
  50 #define MIN_ARP_SEND_TIME 2000
  51 #define MAX_ARP_SEND_TIME 32000
  52 #define GRATUITOUS_ARP_MAC_ADDR "00:00:00:00:00:00"
  53 #define UCHAR_TO_ADDRESS(hwaddr, buf) do {\
  54                 snprintf(buf, WLAN_MAC_ADDR_MAX,\
  55                 "%02X:%02X:%02X:%02X:%02X:%02X", hwaddr[0], hwaddr[1],\
  56                 hwaddr[2], hwaddr[3], hwaddr[4], hwaddr[5]);\
  57                 } while (0)
  58
  59 struct arp_message {
  60         /* Ethernet header */
  61         unsigned char   h_dest[MAC_ADDRESS_LENGTH];     /* destination ether addr */
  62         unsigned char   h_source[MAC_ADDRESS_LENGTH];   /* source ether addr */
  63         unsigned short  h_proto;                                /* packet type ID field */
  64
  65         /* ARP packet */
  66         unsigned short hw_type;                         /* hardware type(ARPHRD_ETHER) */
  67         unsigned short p_type;                          /* protocol type(ETH_P_IP) */
  68         unsigned char  hw_len;                          /* hardware address length */
  69         unsigned char  p_len;                                   /* protocol address length */
  70         unsigned short operation;                               /* ARP opcode */
  71         unsigned char  s_hwaddr[MAC_ADDRESS_LENGTH];            /* sender hardware address */
  72         unsigned char  s_IPaddr[IP_ADDRESS_LENGTH];             /* sender IP address */
  73         unsigned char  t_hwaddr[MAC_ADDRESS_LENGTH];            /* target hardware address */
  74         unsigned char  t_IPaddr[IP_ADDRESS_LENGTH];             /* target IP address */
  75         unsigned char  pad[18];                         /* pad for min. Ethernet payload (60 bytes) */
  76 };
  77
  78 typedef enum {
  79         NETCONFIG_IP_CONFLICT_STATE_UNKNOWN,
  80         NETCONFIG_IP_CONFLICT_STATE_CONFLICT_NOT_DETECTED,
  81         NETCONFIG_IP_CONFLICT_STATE_CONFLICT_DETECTED
  82 } ip_conflict_state_e;
  83
  84 struct timer_data {
  85         guint initial_time;
  86         guint timeout;
  87 };
  88 static struct timer_data td = {
  89         MIN_ARP_SEND_TIME, MIN_ARP_SEND_TIME
  90 };
  91
  92 int ioctl_sock;
  93 bool is_ip_conflict_detect_enabled = true;
  94 static gboolean send_arp(gpointer data);
  95 static void __netconfig_wifi_notify_ip_conflict(char *state, char *mac);
  96 ip_conflict_state_e conflict_state = NETCONFIG_IP_CONFLICT_STATE_CONFLICT_NOT_DETECTED;
  97
  98 struct sock_data *sd;
  99
 100 typedef unsigned int in_addr_t;
 101
 102 union uchar_to_uint {
 103         unsigned int uint;
 104         unsigned char uchar[IP_ADDRESS_LENGTH];
 105 };
 106
 107 static unsigned int __convert_uchar_to_uint(unsigned char b[IP_ADDRESS_LENGTH])
 108 {
 109         int idx = 0;
 110         union uchar_to_uint u;
 111         for (; idx < IP_ADDRESS_LENGTH; ++idx)
 112                 u.uchar[idx] = b[idx];
 113
 114         return u.uint;
 115 }
 116
 117 static gboolean __arp_reply_timeout_cb(gpointer data)
 118 {
 119         if (sd == NULL) {
 120                 INFO("Ignore timeout cb");
 121                 return G_SOURCE_REMOVE;
 122         }
 123
 124         sd->iteration++;
 125         sd->arp_reply_timer = -1;
 126         if (sd->timer_id != -1)
 127                 g_source_remove(sd->timer_id);
 128
 129         if (conflict_state != NETCONFIG_IP_CONFLICT_STATE_CONFLICT_NOT_DETECTED && sd->iteration == 5) {
 130                 sd->iteration = 0;
 131                 conflict_state = NETCONFIG_IP_CONFLICT_STATE_CONFLICT_NOT_DETECTED;
 132                 __netconfig_wifi_notify_ip_conflict("resolved", GRATUITOUS_ARP_MAC_ADDR);
 133         }
 134
 135         sd->timer_id = g_timeout_add(sd->timeout, send_arp, sd);
 136         return G_SOURCE_REMOVE;
 137 }
 138
 139 static gboolean __netconfig_check_arp_receive(GIOChannel *source,
 140                                                   GIOCondition condition, gpointer data)
 141 {
 142         struct sock_data *sd = data;
 143         gchar buffer[ARP_PACKET_SIZE] = {0, };
 144         gsize bytes_read = 0;
 145         struct arp_message arp_recv;
 146         char sbuf[WLAN_MAC_ADDR_MAX];
 147         char tbuf[WLAN_MAC_ADDR_MAX];
 148         const char *default_ip = NULL;
 149
 150         if (g_io_channel_read_chars(source, buffer, ARP_PACKET_SIZE,
 151                                 &bytes_read, NULL) == G_IO_STATUS_NORMAL) {
 152                 unsigned int target_ip = 0;
 153
 154                 memset(&arp_recv, 0, sizeof(arp_recv));
 155                 memcpy(&arp_recv, buffer, sizeof(buffer));
 156
 157                 default_ip = netconfig_get_default_ipaddress();
 158                 if (default_ip == NULL) {
 159                         INFO("ip address is not set yet");
 160                         goto out;
 161                 }
 162                 target_ip = inet_addr(default_ip);
 163
 164
 165                 /* Only handle ARP replies */
 166                 if (arp_recv.operation != htons(ARPOP_REPLY))
 167                         goto out;
 168
 169                 UCHAR_TO_ADDRESS(arp_recv.t_hwaddr, tbuf);
 170                 UCHAR_TO_ADDRESS(arp_recv.s_hwaddr, sbuf);
 171
 172                 int zero_mac = strcmp(tbuf , GRATUITOUS_ARP_MAC_ADDR);
 173                 if (zero_mac == 0) {
 174                         DBG("Broadcast packet.\n");
 175                         goto skip;
 176                 }
 177                 DBG("our mac= %s source mac= %s target mac= %s", netconfig_get_default_mac_address(), sbuf, tbuf);
 178                 int mac_cmp = strcmp(tbuf , netconfig_get_default_mac_address());
 179                 if (mac_cmp != 0) {
 180                         INFO("Packet not intended to us.\n");
 181                         goto out;
 182                 }
 183 skip:
 184                 mac_cmp = strcmp(sbuf, netconfig_get_default_mac_address());
 185                 DBG("target ip = %d source ip = %d", target_ip, __convert_uchar_to_uint(arp_recv.s_IPaddr));
 186                 if ((mac_cmp != 0) && (__convert_uchar_to_uint(arp_recv.s_IPaddr) == target_ip)) {
 187                         sd->iteration = 0;
 188                         if (conflict_state != NETCONFIG_IP_CONFLICT_STATE_CONFLICT_DETECTED) {
 189                                 INFO("ip conflict is detected !\n");
 190                                 conflict_state = NETCONFIG_IP_CONFLICT_STATE_CONFLICT_DETECTED;
 191                                 __netconfig_wifi_notify_ip_conflict("conflict", sbuf);
 192                         }
 193
 194                         if (sd->arp_reply_timer != -1) {
 195                                 g_source_remove(sd->arp_reply_timer);
 196                                 sd->arp_reply_timer = -1;
 197                         }
 198
 199                         if (sd->timer_id)
 200                                 g_source_remove(sd->timer_id);
 201                         sd->timer_id = g_timeout_add(sd->timeout, send_arp, sd);
 202
 203                 }
 204         }
 205
 206 out:
 207         return TRUE;
 208 }
 209
 210 static gboolean send_arp(gpointer data)
 211 {
 212         struct sock_data *sd = data;
 213         struct ether_addr *source_mac = NULL;
 214         struct arp_message arp;
 215         char error_buf[MAX_SIZE_ERROR_BUFFER] = {0, };
 216         unsigned int source_ip = 0;
 217         unsigned int target_ip = 0;
 218         const unsigned char broadcast_addr[] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
 219         struct sockaddr_ll addr = {0};
 220         struct ifreq net_ifr;
 221         int ifindex = 0;
 222         errno = 0;
 223         const char *default_ip = NULL;
 224
 225         const char *mac = netconfig_get_default_mac_address();
 226         if (mac == NULL)
 227                 goto err;
 228         source_mac = ether_aton(mac);
 229         if (source_mac == NULL) {
 230                 INFO("Mac address is NULL");
 231                 goto err;
 232         }
 233
 234         memset(&arp, 0, sizeof(arp));
 235
 236         unsigned char  broadcast_mac_addr[MAC_ADDRESS_LENGTH];
 237         memset(broadcast_mac_addr, 0xff, sizeof(broadcast_mac_addr));
 238         memcpy(arp.h_dest, broadcast_mac_addr, MAC_ADDRESS_LENGTH);             /* MAC dest */
 239         memcpy(arp.h_source, source_mac, MAC_ADDRESS_LENGTH);                   /* MAC source */
 240
 241         arp.h_proto = htons(ETH_P_ARP);                                         /* protocol type (Ethernet) */
 242         arp.hw_type = htons(ARPHRD_ETHER);                                      /* hardware type */
 243         arp.p_type = htons(ETH_P_IP);                                           /* protocol type (ARP message) */
 244         arp.hw_len = MAC_ADDRESS_LENGTH;                                        /* hardware address length */
 245         arp.p_len = IP_ADDRESS_LENGTH;                                          /* protocol address length */
 246         arp.operation = htons(ARPOP_REQUEST);                                   /* ARP op code */
 247         default_ip = netconfig_get_default_ipaddress();
 248         if (default_ip == NULL) {
 249                 INFO("ip address is not set yet");
 250                 goto err;
 251         }
 252
 253         source_ip = inet_addr(ARP_SOURCE_IP);
 254         target_ip = inet_addr(default_ip);
 255         memcpy(arp.s_IPaddr, &source_ip, IP_ADDRESS_LENGTH);                    /* source IP address */
 256         memcpy(arp.s_hwaddr, source_mac, MAC_ADDRESS_LENGTH);                   /* source hardware address */
 257         memcpy(arp.t_IPaddr, &target_ip, IP_ADDRESS_LENGTH);                    /* target IP addressshek" */
 258
 259         memset(&net_ifr, 0, sizeof(net_ifr));
 260         /* ifreq structure creation */
 261         size_t if_name_len = strlen(netconfig_get_default_ifname());
 262         if (if_name_len < sizeof(net_ifr.ifr_name)) {
 263                 memcpy(net_ifr.ifr_name, netconfig_get_default_ifname(), if_name_len);
 264                 net_ifr.ifr_name[if_name_len] = 0;
 265         } else {
 266                 INFO("Error : Interface name is too long");
 267                 goto err;
 268         }
 269
 270         if (ioctl(sd->chk_conflict_sd, SIOCGIFINDEX, &net_ifr) == -1) {
 271                 strerror_r(errno, error_buf, MAX_SIZE_ERROR_BUFFER);
 272                 INFO("ioctl Failed. Error..... = %s\n", error_buf);
 273                 goto err;
 274         }
 275
 276         ifindex = net_ifr.ifr_ifindex;
 277         /* Construct the destination address */
 278         addr.sll_family = AF_PACKET;
 279         addr.sll_ifindex = ifindex;
 280         addr.sll_halen = ETHER_ADDR_LEN;
 281         addr.sll_protocol = htons(ETH_P_ARP);
 282         memcpy(addr.sll_addr, broadcast_addr, ETHER_ADDR_LEN);
 283
 284         if (sendto(sd->chk_conflict_sd, &arp, sizeof(arp), 0, (struct sockaddr*)&addr, sizeof(addr)) < 0) {
 285                 strerror_r(errno, error_buf, MAX_SIZE_ERROR_BUFFER);
 286                 INFO("Sending ARP Packet Failed. Error. = %s\n", error_buf);
 287                 /* close socket */
 288                 if (-1 < sd->chk_conflict_sd) {
 289                         close(sd->chk_conflict_sd);
 290                         sd->chk_conflict_sd = -1;
 291                 }
 292
 293                 /* reopen socket */
 294                 if ((sd->chk_conflict_sd = socket(AF_PACKET, SOCK_RAW, htons(ETH_P_ARP))) == -1) {
 295                         INFO("socket %d", sd->chk_conflict_sd);
 296                         strerror_r(errno, error_buf, MAX_SIZE_ERROR_BUFFER);
 297                         INFO("socket Failed. Error = %s\n", error_buf);
 298                 }
 299                 goto err;
 300         } else {
 301                 DBG("Sent ARP Packet \n");
 302         }
 303
 304         g_source_remove(sd->timer_id);
 305
 306         sd->timeout = td.initial_time;
 307
 308         /* Adding timeout callback for arp request */
 309         sd->arp_reply_timer = g_timeout_add(1000, __arp_reply_timeout_cb,
 310                                         (gpointer) &sd->arp_reply_timer);
 311         return FALSE;
 312 err:
 313         if (sd->timer_id)
 314                 g_source_remove(sd->timer_id);
 315         sd->timer_id = g_timeout_add(sd->timeout, send_arp, sd);
 316         return FALSE;
 317 }
 318
 319 struct sock_data * start_ip_conflict_mon(void)
 320 {
 321         if (is_ip_conflict_detect_enabled == false) {
 322                 INFO("detection mode is set to false");
 323                 return NULL;
 324         }
 325
 326         char error_buf[MAX_SIZE_ERROR_BUFFER] = {0, };
 327
 328         sd = g_try_malloc0(sizeof(struct sock_data));
 329         if (sd == NULL) {
 330                 INFO("Failed to malloc sock_data");
 331                 return NULL;
 332         }
 333         sd->chk_conflict_data_id = -1;
 334         sd->chk_conflict_sd = -1;
 335         sd->timer_id = 0;
 336         sd->iteration = 0;
 337
 338         if ((sd->chk_conflict_sd = socket(AF_PACKET, SOCK_RAW, htons(ETH_P_ARP))) == -1) {
 339                 strerror_r(errno, error_buf, MAX_SIZE_ERROR_BUFFER);
 340                 INFO("socket Failed. Error = %s\n", error_buf);
 341                 g_free(sd);
 342                 return NULL;
 343         } else {
 344                 sd->chk_conflict_sock_io = g_io_channel_unix_new(sd->chk_conflict_sd);
 345                 if (sd->chk_conflict_sock_io == NULL) {
 346                         INFO("Failed to create channel");
 347                         INFO("Exit");
 348                         g_free(sd);
 349                         return NULL;
 350                 }
 351
 352                 g_io_channel_set_close_on_unref(sd->chk_conflict_sock_io, TRUE);
 353
 354                 if (G_IO_STATUS_NORMAL != g_io_channel_set_encoding(sd->chk_conflict_sock_io,
 355                                                                    NULL, NULL))
 356                         INFO("Failed to set encoding NULL on io channel");
 357                 if (G_IO_STATUS_NORMAL != g_io_channel_set_flags(sd->chk_conflict_sock_io,
 358                                                                 G_IO_FLAG_NONBLOCK, NULL))
 359                         INFO("Failed to set flags on io channel");
 360                 sd->chk_conflict_data_id = g_io_add_watch(sd->chk_conflict_sock_io, G_IO_IN,
 361                                                           __netconfig_check_arp_receive, sd);
 362                 DBG("socket %d", sd->chk_conflict_sd);
 363
 364                 sd->timeout = td.initial_time;
 365                 send_arp(sd);
 366                 return sd;
 367         }
 368 }
 369
 370 void stop_ip_conflict_mon()
 371 {
 372         INFO("+");
 373         GError* error = NULL;
 374         if (sd == NULL) {
 375                 INFO("sd is NULL");
 376                 return;
 377         }
 378         if (-1 < sd->chk_conflict_sd) {
 379                 if (G_IO_STATUS_NORMAL !=
 380                     g_io_channel_shutdown(sd->chk_conflict_sock_io, FALSE,
 381                                           &error)) {
 382                         INFO("Failure received while shutdown io channel[%d]:[%s]", error->code, error->message);
 383                         g_error_free(error);
 384                 }
 385                 g_io_channel_unref(sd->chk_conflict_sock_io);
 386                 g_source_remove(sd->chk_conflict_data_id);
 387                 sd->chk_conflict_data_id = -1;
 388                 close(sd->chk_conflict_sd);
 389                 sd->chk_conflict_sd = -1;
 390         }
 391         if (sd->timer_id > 0) {
 392                 g_source_remove(sd->timer_id);
 393                 sd->timer_id = 0;
 394         }
 395         g_free(sd);
 396         sd = NULL;
 397         INFO("Monitoring stopped");
 398 }
 399
 400 static void __netconfig_wifi_notify_ip_conflict(char *state, char *mac)
 401 {
 402         GVariantBuilder *builder = NULL;
 403
 404         builder = g_variant_builder_new(G_VARIANT_TYPE("a{sv}"));
 405         g_variant_builder_add(builder, "{sv}", "state", g_variant_new_string(state));
 406         g_variant_builder_add(builder, "{sv}", "mac", g_variant_new_string(mac));
 407
 408         wifi_emit_ip_conflict_event((Wifi *)get_wifi_object(), g_variant_builder_end(builder));
 409         g_variant_builder_unref(builder);
 410
 411         /* send notification using net-popup */
 412         if (!strcmp(state, "conflict"))
 413                 netconfig_send_notification_to_net_popup(NETCONFIG_ADD_IP_CONFLICT_NOTI, mac);
 414         else
 415                 netconfig_send_notification_to_net_popup(NETCONFIG_DEL_IP_CONFLICT_NOTI, mac);
 416
 417         return;
 418 }
 419
 420 gboolean handle_ip_conflict_set_enable(Wifi *wifi, GDBusMethodInvocation *context,
 421                                        bool detect)
 422 {
 423         g_return_val_if_fail(wifi != NULL, FALSE);
 424
 425
 426         if (detect == false) {
 427                 is_ip_conflict_detect_enabled = false;
 428                 conflict_state = NETCONFIG_IP_CONFLICT_STATE_UNKNOWN;
 429                 if (sd != NULL)
 430                         stop_ip_conflict_mon();
 431                 else {
 432                         netconfig_error_dbus_method_return(context, NETCONFIG_ERROR_INTERNAL, "AlreadyExists");
 433                         wifi_complete_ip_conflict_set_enable(wifi, context);
 434                         return FALSE;
 435                 }
 436         } else {
 437                 is_ip_conflict_detect_enabled = true;
 438                 conflict_state = NETCONFIG_IP_CONFLICT_STATE_CONFLICT_NOT_DETECTED;
 439                 if (sd == NULL) {
 440                         if (start_ip_conflict_mon() == NULL) {
 441                                 INFO("Failed to start IP conflict monitoring");
 442                                 netconfig_error_dbus_method_return(context,
 443                                                 NETCONFIG_ERROR_INTERNAL, "Failed");
 444                                 wifi_complete_ip_conflict_set_enable(wifi, context);
 445                                 return FALSE;
 446                         }
 447                 } else {
 448                         netconfig_error_dbus_method_return(context, NETCONFIG_ERROR_INTERNAL, "AlreadyExists");
 449                         wifi_complete_ip_conflict_set_enable(wifi, context);
 450                         return FALSE;
 451                 }
 452         }
 453
 454         wifi_complete_ip_conflict_set_enable(wifi, context);
 455         return TRUE;
 456 }
 457
 458 gboolean handle_is_ip_conflict_detect_enabled(Wifi *wifi, GDBusMethodInvocation *context)
 459 {
 460         g_return_val_if_fail(wifi != NULL, FALSE);
 461         GVariant *param = NULL;
 462         param = g_variant_new("(b)", is_ip_conflict_detect_enabled);
 463         g_dbus_method_invocation_return_value(context, param);
 464         return TRUE;
 465 }
 466
 467 gboolean handle_set_ip_conflict_period(Wifi *wifi, GDBusMethodInvocation *context, guint initial_time)
 468 {
 469         g_return_val_if_fail(wifi != NULL, FALSE);
 470         if (initial_time < MAX_ARP_SEND_TIME && initial_time > MIN_ARP_SEND_TIME)
 471                 return FALSE;
 472
 473         td.initial_time = 1000 * initial_time;
 474         // remove timer
 475         stop_ip_conflict_mon();
 476         start_ip_conflict_mon();
 477         wifi_complete_set_ip_conflict_period(wifi, context);
 478         return TRUE;
 479 }
 480
 481 gboolean handle_get_ip_conflict_state(Wifi *wifi, GDBusMethodInvocation *context)
 482 {
 483         g_return_val_if_fail(wifi != NULL, FALSE);
 484         GVariant *param = NULL;
 485         param = g_variant_new("(u)", conflict_state);
 486         g_dbus_method_invocation_return_value(context, param);
 487         return TRUE;
 488 }
 489
 490 gboolean handle_get_ip_conflict_period(Wifi *wifi, GDBusMethodInvocation *context)
 491 {
 492         g_return_val_if_fail(wifi != NULL, FALSE);
 493         GVariant *param = NULL;
 494         param = g_variant_new("(u)", td.initial_time/1000);
 495         g_dbus_method_invocation_return_value(context, param);
 496         return TRUE;
 497 }