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 #define INITIAL_BURST_ARP_COUNT 5
  50
  51 #define CONFLICT_REMOVE_ITERATION_LIMIT 4
  52 #define MIN_ARP_SEND_TIME 20000
  53 #define BURST_ARP_SEND_TIME 3000
  54 #define MAX_ARP_SEND_TIME 32000
  55 #define GRATUITOUS_ARP_MAC_ADDR "00:00:00:00:00:00"
  56 #define UCHAR_TO_ADDRESS(hwaddr, buf) do {\
  57                 snprintf(buf, WLAN_MAC_ADDR_MAX,\
  58                 "%02X:%02X:%02X:%02X:%02X:%02X", hwaddr[0], hwaddr[1],\
  59                 hwaddr[2], hwaddr[3], hwaddr[4], hwaddr[5]);\
  60                 } while (0)
  61
  62 struct arp_message {
  63         /* Ethernet header */
  64         unsigned char   h_dest[MAC_ADDRESS_LENGTH];     /* destination ether addr */
  65         unsigned char   h_source[MAC_ADDRESS_LENGTH];   /* source ether addr */
  66         unsigned short  h_proto;                                /* packet type ID field */
  67
  68         /* ARP packet */
  69         unsigned short hw_type;                         /* hardware type(ARPHRD_ETHER) */
  70         unsigned short p_type;                          /* protocol type(ETH_P_IP) */
  71         unsigned char  hw_len;                          /* hardware address length */
  72         unsigned char  p_len;                                   /* protocol address length */
  73         unsigned short operation;                               /* ARP opcode */
  74         unsigned char  s_hwaddr[MAC_ADDRESS_LENGTH];            /* sender hardware address */
  75         unsigned char  s_IPaddr[IP_ADDRESS_LENGTH];             /* sender IP address */
  76         unsigned char  t_hwaddr[MAC_ADDRESS_LENGTH];            /* target hardware address */
  77         unsigned char  t_IPaddr[IP_ADDRESS_LENGTH];             /* target IP address */
  78         unsigned char  pad[18];                         /* pad for min. Ethernet payload (60 bytes) */
  79 };
  80
  81 typedef enum {
  82         NETCONFIG_IP_CONFLICT_STATE_UNKNOWN,
  83         NETCONFIG_IP_CONFLICT_STATE_CONFLICT_NOT_DETECTED,
  84         NETCONFIG_IP_CONFLICT_STATE_CONFLICT_DETECTED
  85 } ip_conflict_state_e;
  86
  87 struct timer_data {
  88         guint initial_time;
  89         guint timeout;
  90 };
  91 static struct timer_data td = {
  92         MIN_ARP_SEND_TIME, MIN_ARP_SEND_TIME
  93 };
  94
  95 int ioctl_sock;
  96 static bool initial_bursts = true;
  97 bool is_ip_conflict_detect_enabled = true;
  98 static gboolean send_arp(gpointer data);
  99 static void __netconfig_wifi_notify_ip_conflict(char *state, char *mac);
 100 ip_conflict_state_e conflict_state = NETCONFIG_IP_CONFLICT_STATE_CONFLICT_NOT_DETECTED;
 101
 102 struct sock_data *sd;
 103
 104 typedef unsigned int in_addr_t;
 105
 106 union uchar_to_uint {
 107         unsigned int uint;
 108         unsigned char uchar[IP_ADDRESS_LENGTH];
 109 };
 110
 111 static unsigned int __convert_uchar_to_uint(unsigned char b[IP_ADDRESS_LENGTH])
 112 {
 113         int idx = 0;
 114         union uchar_to_uint u;
 115         for (; idx < IP_ADDRESS_LENGTH; ++idx)
 116                 u.uchar[idx] = b[idx];
 117
 118         return u.uint;
 119 }
 120
 121 static gboolean __arp_reply_timeout_cb(gpointer data)
 122 {
 123         if (sd == NULL) {
 124                 INFO("Ignore timeout cb");
 125                 return G_SOURCE_REMOVE;
 126         }
 127
 128         sd->iteration++;
 129         sd->arp_reply_timer = -1;
 130         if (sd->timer_id != -1)
 131                 g_source_remove(sd->timer_id);
 132
 133         if (conflict_state != NETCONFIG_IP_CONFLICT_STATE_CONFLICT_NOT_DETECTED &&
 134                         sd->iteration == CONFLICT_REMOVE_ITERATION_LIMIT) {
 135                 sd->iteration = 0;
 136                 conflict_state = NETCONFIG_IP_CONFLICT_STATE_CONFLICT_NOT_DETECTED;
 137                 __netconfig_wifi_notify_ip_conflict("resolved", GRATUITOUS_ARP_MAC_ADDR);
 138                 initial_bursts = true;
 139         }
 140
 141         sd->timer_id = g_timeout_add(sd->timeout, send_arp, sd);
 142         return G_SOURCE_REMOVE;
 143 }
 144
 145 static gboolean __netconfig_check_arp_receive(GIOChannel *source,
 146                                                   GIOCondition condition, gpointer data)
 147 {
 148         struct sock_data *sd = data;
 149         gchar buffer[ARP_PACKET_SIZE] = {0, };
 150         gsize bytes_read = 0;
 151         struct arp_message arp_recv;
 152         char sbuf[WLAN_MAC_ADDR_MAX];
 153         char tbuf[WLAN_MAC_ADDR_MAX];
 154         const char *default_ip = NULL;
 155
 156         if (g_io_channel_read_chars(source, buffer, ARP_PACKET_SIZE,
 157                                 &bytes_read, NULL) == G_IO_STATUS_NORMAL) {
 158                 unsigned int target_ip = 0;
 159
 160                 memset(&arp_recv, 0, sizeof(arp_recv));
 161                 memcpy(&arp_recv, buffer, sizeof(buffer));
 162
 163                 default_ip = netconfig_get_default_ipaddress();
 164                 if (default_ip == NULL) {
 165                         INFO("ip address is not set yet");
 166                         goto out;
 167                 }
 168                 target_ip = inet_addr(default_ip);
 169
 170
 171                 /* Only handle ARP replies */
 172                 if (arp_recv.operation != htons(ARPOP_REPLY))
 173                         goto out;
 174
 175                 UCHAR_TO_ADDRESS(arp_recv.t_hwaddr, tbuf);
 176                 UCHAR_TO_ADDRESS(arp_recv.s_hwaddr, sbuf);
 177
 178                 int zero_mac = strcmp(tbuf , GRATUITOUS_ARP_MAC_ADDR);
 179                 if (zero_mac == 0) {
 180                         DBG("Broadcast packet.\n");
 181                         goto skip;
 182                 }
 183                 DBG("our mac= %s source mac= %s target mac= %s", netconfig_get_default_mac_address(), sbuf, tbuf);
 184                 int mac_cmp = strcmp(tbuf , netconfig_get_default_mac_address());
 185                 if (mac_cmp != 0) {
 186                         INFO("Packet not intended to us.\n");
 187                         goto out;
 188                 }
 189 skip:
 190                 mac_cmp = strcmp(sbuf, netconfig_get_default_mac_address());
 191                 DBG("target ip = %d source ip = %d", target_ip, __convert_uchar_to_uint(arp_recv.s_IPaddr));
 192                 if ((mac_cmp != 0) && (__convert_uchar_to_uint(arp_recv.s_IPaddr) == target_ip)) {
 193                         sd->iteration = 0;
 194                         if (conflict_state != NETCONFIG_IP_CONFLICT_STATE_CONFLICT_DETECTED) {
 195                                 INFO("ip conflict is detected !\n");
 196                                 conflict_state = NETCONFIG_IP_CONFLICT_STATE_CONFLICT_DETECTED;
 197                                 __netconfig_wifi_notify_ip_conflict("conflict", sbuf);
 198                                 sd->timeout = BURST_ARP_SEND_TIME;
 199                         }
 200
 201                         if (sd->arp_reply_timer != -1) {
 202                                 g_source_remove(sd->arp_reply_timer);
 203                                 sd->arp_reply_timer = -1;
 204                         }
 205
 206                         if (sd->timer_id)
 207                                 g_source_remove(sd->timer_id);
 208                         sd->timer_id = g_timeout_add(sd->timeout, send_arp, sd);
 209
 210                 }
 211         }
 212
 213 out:
 214         return TRUE;
 215 }
 216
 217 static gboolean send_arp(gpointer data)
 218 {
 219         struct sock_data *sd = data;
 220         struct ether_addr *source_mac = NULL;
 221         struct arp_message arp;
 222         char error_buf[MAX_SIZE_ERROR_BUFFER] = {0, };
 223         unsigned int source_ip = 0;
 224         unsigned int target_ip = 0;
 225         const unsigned char broadcast_addr[] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
 226         struct sockaddr_ll addr = {0};
 227         struct ifreq net_ifr;
 228         int ifindex = 0;
 229         errno = 0;
 230         const char *default_ip = NULL;
 231         static int initial_send_arp_count = 0;
 232
 233         if (initial_bursts && initial_send_arp_count >= INITIAL_BURST_ARP_COUNT) {
 234                 initial_bursts = false;
 235                 initial_send_arp_count = 0;
 236         }
 237
 238         if (initial_bursts)
 239                 initial_send_arp_count++;
 240
 241         const char *mac = netconfig_get_default_mac_address();
 242         if (mac == NULL)
 243                 goto err;
 244         source_mac = ether_aton(mac);
 245         if (source_mac == NULL) {
 246                 INFO("Mac address is NULL");
 247                 goto err;
 248         }
 249
 250         memset(&arp, 0, sizeof(arp));
 251
 252         unsigned char  broadcast_mac_addr[MAC_ADDRESS_LENGTH];
 253         memset(broadcast_mac_addr, 0xff, sizeof(broadcast_mac_addr));
 254         memcpy(arp.h_dest, broadcast_mac_addr, MAC_ADDRESS_LENGTH);             /* MAC dest */
 255         memcpy(arp.h_source, source_mac, MAC_ADDRESS_LENGTH);                   /* MAC source */
 256
 257         arp.h_proto = htons(ETH_P_ARP);                                         /* protocol type (Ethernet) */
 258         arp.hw_type = htons(ARPHRD_ETHER);                                      /* hardware type */
 259         arp.p_type = htons(ETH_P_IP);                                           /* protocol type (ARP message) */
 260         arp.hw_len = MAC_ADDRESS_LENGTH;                                        /* hardware address length */
 261         arp.p_len = IP_ADDRESS_LENGTH;                                          /* protocol address length */
 262         arp.operation = htons(ARPOP_REQUEST);                                   /* ARP op code */
 263         default_ip = netconfig_get_default_ipaddress();
 264         if (default_ip == NULL) {
 265                 INFO("ip address is not set yet");
 266                 goto err;
 267         }
 268
 269         source_ip = inet_addr(ARP_SOURCE_IP);
 270         target_ip = inet_addr(default_ip);
 271         memcpy(arp.s_IPaddr, &source_ip, IP_ADDRESS_LENGTH);                    /* source IP address */
 272         memcpy(arp.s_hwaddr, source_mac, MAC_ADDRESS_LENGTH);                   /* source hardware address */
 273         memcpy(arp.t_IPaddr, &target_ip, IP_ADDRESS_LENGTH);                    /* target IP addressshek" */
 274
 275         memset(&net_ifr, 0, sizeof(net_ifr));
 276         /* ifreq structure creation */
 277         size_t if_name_len = strlen(netconfig_get_default_ifname());
 278         if (if_name_len < sizeof(net_ifr.ifr_name)) {
 279                 memcpy(net_ifr.ifr_name, netconfig_get_default_ifname(), if_name_len);
 280                 net_ifr.ifr_name[if_name_len] = 0;
 281         } else {
 282                 INFO("Error : Interface name is too long");
 283                 goto err;
 284         }
 285
 286         if (ioctl(sd->chk_conflict_sd, SIOCGIFINDEX, &net_ifr) == -1) {
 287                 strerror_r(errno, error_buf, MAX_SIZE_ERROR_BUFFER);
 288                 INFO("ioctl Failed. Error..... = %s\n", error_buf);
 289                 goto err;
 290         }
 291
 292         ifindex = net_ifr.ifr_ifindex;
 293         /* Construct the destination address */
 294         addr.sll_family = AF_PACKET;
 295         addr.sll_ifindex = ifindex;
 296         addr.sll_halen = ETHER_ADDR_LEN;
 297         addr.sll_protocol = htons(ETH_P_ARP);
 298         memcpy(addr.sll_addr, broadcast_addr, ETHER_ADDR_LEN);
 299
 300         if (sendto(sd->chk_conflict_sd, &arp, sizeof(arp), 0, (struct sockaddr*)&addr, sizeof(addr)) < 0) {
 301                 strerror_r(errno, error_buf, MAX_SIZE_ERROR_BUFFER);
 302                 INFO("Sending ARP Packet Failed. Error. = %s\n", error_buf);
 303                 /* close socket */
 304                 if (-1 < sd->chk_conflict_sd) {
 305                         close(sd->chk_conflict_sd);
 306                         sd->chk_conflict_sd = -1;
 307                 }
 308
 309                 /* reopen socket */
 310                 if ((sd->chk_conflict_sd = socket(AF_PACKET, SOCK_RAW, htons(ETH_P_ARP))) == -1) {
 311                         INFO("socket %d", sd->chk_conflict_sd);
 312                         strerror_r(errno, error_buf, MAX_SIZE_ERROR_BUFFER);
 313                         INFO("socket Failed. Error = %s\n", error_buf);
 314                 }
 315                 goto err;
 316         } else {
 317                 DBG("Sent ARP Packet \n");
 318         }
 319
 320         g_source_remove(sd->timer_id);
 321
 322         if (conflict_state == NETCONFIG_IP_CONFLICT_STATE_CONFLICT_DETECTED || initial_bursts)
 323                 sd->timeout = BURST_ARP_SEND_TIME;
 324         else
 325                 sd->timeout = td.initial_time;
 326
 327         /* Adding timeout callback for arp request */
 328         sd->arp_reply_timer = g_timeout_add(1000, __arp_reply_timeout_cb,
 329                                         (gpointer) &sd->arp_reply_timer);
 330         return FALSE;
 331 err:
 332         if (sd->timer_id)
 333                 g_source_remove(sd->timer_id);
 334         sd->timer_id = g_timeout_add(sd->timeout, send_arp, sd);
 335         return FALSE;
 336 }
 337
 338 struct sock_data * start_ip_conflict_mon(void)
 339 {
 340         if (is_ip_conflict_detect_enabled == false) {
 341                 INFO("detection mode is set to false");
 342                 return NULL;
 343         }
 344
 345         char error_buf[MAX_SIZE_ERROR_BUFFER] = {0, };
 346         initial_bursts = true;
 347
 348         sd = g_try_malloc0(sizeof(struct sock_data));
 349         if (sd == NULL) {
 350                 INFO("Failed to malloc sock_data");
 351                 return NULL;
 352         }
 353         sd->chk_conflict_data_id = -1;
 354         sd->chk_conflict_sd = -1;
 355         sd->timer_id = 0;
 356         sd->iteration = 0;
 357
 358         if ((sd->chk_conflict_sd = socket(AF_PACKET, SOCK_RAW, htons(ETH_P_ARP))) == -1) {
 359                 strerror_r(errno, error_buf, MAX_SIZE_ERROR_BUFFER);
 360                 INFO("socket Failed. Error = %s\n", error_buf);
 361                 g_free(sd);
 362                 return NULL;
 363         } else {
 364                 sd->chk_conflict_sock_io = g_io_channel_unix_new(sd->chk_conflict_sd);
 365                 if (sd->chk_conflict_sock_io == NULL) {
 366                         INFO("Failed to create channel");
 367                         INFO("Exit");
 368                         g_free(sd);
 369                         return NULL;
 370                 }
 371
 372                 g_io_channel_set_close_on_unref(sd->chk_conflict_sock_io, TRUE);
 373
 374                 if (G_IO_STATUS_NORMAL != g_io_channel_set_encoding(sd->chk_conflict_sock_io,
 375                                                                    NULL, NULL))
 376                         INFO("Failed to set encoding NULL on io channel");
 377                 if (G_IO_STATUS_NORMAL != g_io_channel_set_flags(sd->chk_conflict_sock_io,
 378                                                                 G_IO_FLAG_NONBLOCK, NULL))
 379                         INFO("Failed to set flags on io channel");
 380                 sd->chk_conflict_data_id = g_io_add_watch(sd->chk_conflict_sock_io, G_IO_IN,
 381                                                           __netconfig_check_arp_receive, sd);
 382                 DBG("socket %d", sd->chk_conflict_sd);
 383
 384                 sd->timeout = td.initial_time;
 385                 send_arp(sd);
 386                 return sd;
 387         }
 388 }
 389
 390 void stop_ip_conflict_mon()
 391 {
 392         INFO("+");
 393         GError* error = NULL;
 394         if (sd == NULL) {
 395                 INFO("sd is NULL");
 396                 return;
 397         }
 398         if (-1 < sd->chk_conflict_sd) {
 399                 if (G_IO_STATUS_NORMAL !=
 400                     g_io_channel_shutdown(sd->chk_conflict_sock_io, FALSE,
 401                                           &error)) {
 402                         INFO("Failure received while shutdown io channel[%d]:[%s]", error->code, error->message);
 403                         g_error_free(error);
 404                 }
 405                 g_io_channel_unref(sd->chk_conflict_sock_io);
 406                 g_source_remove(sd->chk_conflict_data_id);
 407                 sd->chk_conflict_data_id = -1;
 408                 close(sd->chk_conflict_sd);
 409                 sd->chk_conflict_sd = -1;
 410         }
 411         if (sd->timer_id > 0) {
 412                 g_source_remove(sd->timer_id);
 413                 sd->timer_id = 0;
 414         }
 415         g_free(sd);
 416         sd = NULL;
 417         INFO("Monitoring stopped");
 418 }
 419
 420 static void __netconfig_wifi_notify_ip_conflict(char *state, char *mac)
 421 {
 422         GVariantBuilder *builder = NULL;
 423
 424         builder = g_variant_builder_new(G_VARIANT_TYPE("a{sv}"));
 425         g_variant_builder_add(builder, "{sv}", "state", g_variant_new_string(state));
 426         g_variant_builder_add(builder, "{sv}", "mac", g_variant_new_string(mac));
 427
 428         wifi_emit_ip_conflict_event((Wifi *)get_wifi_object(), g_variant_builder_end(builder));
 429         g_variant_builder_unref(builder);
 430
 431         /* send notification using net-popup */
 432         if (!strcmp(state, "conflict"))
 433                 netconfig_send_notification_to_net_popup(NETCONFIG_ADD_IP_CONFLICT_NOTI, mac);
 434         else
 435                 netconfig_send_notification_to_net_popup(NETCONFIG_DEL_IP_CONFLICT_NOTI, mac);
 436
 437         return;
 438 }
 439
 440 gboolean handle_ip_conflict_set_enable(Wifi *wifi, GDBusMethodInvocation *context,
 441                                        bool detect)
 442 {
 443         g_return_val_if_fail(wifi != NULL, FALSE);
 444
 445
 446         if (detect == false) {
 447                 is_ip_conflict_detect_enabled = false;
 448                 conflict_state = NETCONFIG_IP_CONFLICT_STATE_UNKNOWN;
 449                 if (sd != NULL)
 450                         stop_ip_conflict_mon();
 451                 else {
 452                         netconfig_error_dbus_method_return(context, NETCONFIG_ERROR_INTERNAL, "AlreadyExists");
 453                         wifi_complete_ip_conflict_set_enable(wifi, context);
 454                         return FALSE;
 455                 }
 456         } else {
 457                 is_ip_conflict_detect_enabled = true;
 458                 conflict_state = NETCONFIG_IP_CONFLICT_STATE_CONFLICT_NOT_DETECTED;
 459                 if (sd == NULL) {
 460                         if (start_ip_conflict_mon() == NULL) {
 461                                 INFO("Failed to start IP conflict monitoring");
 462                                 netconfig_error_dbus_method_return(context,
 463                                                 NETCONFIG_ERROR_INTERNAL, "Failed");
 464                                 wifi_complete_ip_conflict_set_enable(wifi, context);
 465                                 return FALSE;
 466                         }
 467                 } else {
 468                         netconfig_error_dbus_method_return(context, NETCONFIG_ERROR_INTERNAL, "AlreadyExists");
 469                         wifi_complete_ip_conflict_set_enable(wifi, context);
 470                         return FALSE;
 471                 }
 472         }
 473
 474         wifi_complete_ip_conflict_set_enable(wifi, context);
 475         return TRUE;
 476 }
 477
 478 gboolean handle_is_ip_conflict_detect_enabled(Wifi *wifi, GDBusMethodInvocation *context)
 479 {
 480         g_return_val_if_fail(wifi != NULL, FALSE);
 481         GVariant *param = NULL;
 482         param = g_variant_new("(b)", is_ip_conflict_detect_enabled);
 483         g_dbus_method_invocation_return_value(context, param);
 484         return TRUE;
 485 }
 486
 487 gboolean handle_set_ip_conflict_period(Wifi *wifi, GDBusMethodInvocation *context, guint initial_time)
 488 {
 489         g_return_val_if_fail(wifi != NULL, FALSE);
 490         if (initial_time < MAX_ARP_SEND_TIME && initial_time > MIN_ARP_SEND_TIME)
 491                 return FALSE;
 492
 493         td.initial_time = 1000 * initial_time;
 494         // remove timer
 495         stop_ip_conflict_mon();
 496         start_ip_conflict_mon();
 497         wifi_complete_set_ip_conflict_period(wifi, context);
 498         return TRUE;
 499 }
 500
 501 gboolean handle_get_ip_conflict_state(Wifi *wifi, GDBusMethodInvocation *context)
 502 {
 503         g_return_val_if_fail(wifi != NULL, FALSE);
 504         GVariant *param = NULL;
 505         param = g_variant_new("(u)", conflict_state);
 506         g_dbus_method_invocation_return_value(context, param);
 507         return TRUE;
 508 }
 509
 510 gboolean handle_get_ip_conflict_period(Wifi *wifi, GDBusMethodInvocation *context)
 511 {
 512         g_return_val_if_fail(wifi != NULL, FALSE);
 513         GVariant *param = NULL;
 514         param = g_variant_new("(u)", td.initial_time/1000);
 515         g_dbus_method_invocation_return_value(context, param);
 516         return TRUE;
 517 }