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[22];                         /* pad for min. Ethernet payload (64 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 = false;
  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
 131         if (conflict_state != NETCONFIG_IP_CONFLICT_STATE_CONFLICT_NOT_DETECTED &&
 132                         sd->iteration == CONFLICT_REMOVE_ITERATION_LIMIT) {
 133                 sd->iteration = 0;
 134                 conflict_state = NETCONFIG_IP_CONFLICT_STATE_CONFLICT_NOT_DETECTED;
 135                 __netconfig_wifi_notify_ip_conflict("resolved", GRATUITOUS_ARP_MAC_ADDR);
 136                 initial_bursts = true;
 137         }
 138
 139         if (sd->timer_id)
 140                 g_source_remove(sd->timer_id);
 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         int mac_cmp = 0;
 156
 157         if (g_io_channel_read_chars(source, buffer, ARP_PACKET_SIZE,
 158                                 &bytes_read, NULL) == G_IO_STATUS_NORMAL) {
 159                 unsigned int target_ip = 0;
 160
 161                 memset(&arp_recv, 0, sizeof(arp_recv));
 162                 memcpy(&arp_recv, buffer, sizeof(buffer));
 163
 164                 default_ip = netconfig_get_default_ipaddress();
 165                 if (default_ip == NULL) {
 166                         INFO("ip address is not set yet");
 167                         goto out;
 168                 }
 169                 target_ip = inet_addr(default_ip);
 170
 171
 172                 /* Only handle ARP replies */
 173                 if (arp_recv.operation != htons(ARPOP_REPLY))
 174                         goto out;
 175
 176                 UCHAR_TO_ADDRESS(arp_recv.t_hwaddr, tbuf);
 177                 UCHAR_TO_ADDRESS(arp_recv.s_hwaddr, sbuf);
 178
 179                 int zero_mac = strcmp(tbuf , GRATUITOUS_ARP_MAC_ADDR);
 180                 if (zero_mac == 0) {
 181                         DBG("Broadcast packet.\n");
 182                         goto skip;
 183                 }
 184                 DBG("our mac= %s source mac= %s target mac= %s", netconfig_get_default_mac_address(), sbuf, tbuf);
 185                 mac_cmp = strcmp(tbuf , netconfig_get_default_mac_address());
 186                 if (mac_cmp != 0) {
 187                         INFO("Packet not intended to us.\n");
 188                         goto out;
 189                 }
 190 skip:
 191                 mac_cmp = strcmp(sbuf, netconfig_get_default_mac_address());
 192                 DBG("target ip = %d source ip = %d", target_ip, __convert_uchar_to_uint(arp_recv.s_IPaddr));
 193                 if ((mac_cmp != 0) && (__convert_uchar_to_uint(arp_recv.s_IPaddr) == target_ip)) {
 194                         sd->iteration = 0;
 195                         if (conflict_state != NETCONFIG_IP_CONFLICT_STATE_CONFLICT_DETECTED) {
 196                                 INFO("ip conflict is detected !\n");
 197                                 conflict_state = NETCONFIG_IP_CONFLICT_STATE_CONFLICT_DETECTED;
 198                                 __netconfig_wifi_notify_ip_conflict("conflict", sbuf);
 199                                 sd->timeout = BURST_ARP_SEND_TIME;
 200                         }
 201
 202                         if (sd->arp_reply_timer != -1) {
 203                                 g_source_remove(sd->arp_reply_timer);
 204                                 sd->arp_reply_timer = -1;
 205                         }
 206
 207                         if (sd->timer_id)
 208                                 g_source_remove(sd->timer_id);
 209                         sd->timer_id = g_timeout_add(sd->timeout, send_arp, sd);
 210                 }
 211         }
 212
 213 out:
 214         return TRUE;
 215 }
 216
 217 static void __close_channel_and_sock(struct sock_data *sd)
 218 {
 219         if (sd == NULL)
 220                 return;
 221
 222         g_io_channel_unref(sd->chk_conflict_sock_io);
 223         g_source_remove(sd->chk_conflict_data_id);
 224         sd->chk_conflict_data_id = -1;
 225
 226         close(sd->chk_conflict_sd);
 227         sd->chk_conflict_sd = -1;
 228 }
 229
 230 static int __open_channel_and_sock(struct sock_data *sd)
 231 {
 232         if (sd == NULL)
 233                 return -1;
 234
 235         if ((sd->chk_conflict_sd = socket(AF_PACKET, SOCK_RAW, htons(ETH_P_ARP))) == -1) {
 236                 INFO("socket Failed.\n");
 237                 return -1;
 238         }
 239
 240         sd->chk_conflict_sock_io = g_io_channel_unix_new(sd->chk_conflict_sd);
 241         if (sd->chk_conflict_sock_io == NULL) {
 242                 INFO("Failed to create channel");
 243                 close(sd->chk_conflict_sd);
 244                 sd->chk_conflict_sd = -1;
 245                 return -1;
 246         }
 247
 248         if (G_IO_STATUS_NORMAL != g_io_channel_set_encoding(sd->chk_conflict_sock_io, NULL, NULL))
 249                 INFO("Failed to set encoding NULL on io channel");
 250
 251         if (G_IO_STATUS_NORMAL != g_io_channel_set_flags(sd->chk_conflict_sock_io,
 252                                 G_IO_FLAG_NONBLOCK, NULL))
 253                 INFO("Failed to set flags on io channel");
 254
 255         sd->chk_conflict_data_id = g_io_add_watch(sd->chk_conflict_sock_io, G_IO_IN,
 256                         __netconfig_check_arp_receive, sd);
 257         DBG("socket %d", sd->chk_conflict_sd);
 258         return 0;
 259 }
 260
 261 static gboolean send_arp(gpointer data)
 262 {
 263         struct sock_data *sd = data;
 264         struct ether_addr *source_mac = NULL;
 265         struct arp_message arp;
 266         char error_buf[MAX_SIZE_ERROR_BUFFER] = {0, };
 267         unsigned int source_ip = 0;
 268         unsigned int target_ip = 0;
 269         const unsigned char broadcast_addr[] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
 270         struct sockaddr_ll addr = {0};
 271         struct ifreq net_ifr;
 272         int ifindex = 0;
 273         errno = 0;
 274         const char *default_ip = NULL;
 275         const char *if_name = NULL;
 276         static int initial_send_arp_count = 0;
 277
 278         if (initial_bursts && initial_send_arp_count >= INITIAL_BURST_ARP_COUNT) {
 279                 initial_bursts = false;
 280                 initial_send_arp_count = 0;
 281         }
 282
 283         if (initial_bursts)
 284                 initial_send_arp_count++;
 285
 286         const char *mac = netconfig_get_default_mac_address();
 287         if (mac == NULL)
 288                 goto err;
 289         source_mac = ether_aton(mac);
 290         if (source_mac == NULL) {
 291                 INFO("Mac address is NULL");
 292                 goto err;
 293         }
 294
 295         memset(&arp, 0, sizeof(arp));
 296
 297         unsigned char  broadcast_mac_addr[MAC_ADDRESS_LENGTH];
 298         memset(broadcast_mac_addr, 0xff, sizeof(broadcast_mac_addr));
 299         memcpy(arp.h_dest, broadcast_mac_addr, MAC_ADDRESS_LENGTH);             /* MAC dest */
 300         memcpy(arp.h_source, source_mac, MAC_ADDRESS_LENGTH);                   /* MAC source */
 301
 302         arp.h_proto = htons(ETH_P_ARP);                                         /* protocol type (Ethernet) */
 303         arp.hw_type = htons(ARPHRD_ETHER);                                      /* hardware type */
 304         arp.p_type = htons(ETH_P_IP);                                           /* protocol type (ARP message) */
 305         arp.hw_len = MAC_ADDRESS_LENGTH;                                        /* hardware address length */
 306         arp.p_len = IP_ADDRESS_LENGTH;                                          /* protocol address length */
 307         arp.operation = htons(ARPOP_REQUEST);                                   /* ARP op code */
 308         default_ip = netconfig_get_default_ipaddress();
 309         if (default_ip == NULL) {
 310                 INFO("ip address is not set yet");
 311                 goto err;
 312         }
 313
 314         source_ip = inet_addr(ARP_SOURCE_IP);
 315         target_ip = inet_addr(default_ip);
 316         memcpy(arp.s_IPaddr, &source_ip, IP_ADDRESS_LENGTH);                    /* source IP address */
 317         memcpy(arp.s_hwaddr, source_mac, MAC_ADDRESS_LENGTH);                   /* source hardware address */
 318         memcpy(arp.t_IPaddr, &target_ip, IP_ADDRESS_LENGTH);                    /* target IP addressshek" */
 319
 320         memset(&net_ifr, 0, sizeof(net_ifr));
 321         /* ifreq structure creation */
 322         if_name = netconfig_get_default_ifname();
 323         size_t if_name_len = strlen(if_name);
 324
 325         if (if_name_len == 0) {
 326                 INFO("Error : Unable to get interface name ");
 327                 goto err;
 328         }
 329
 330         if (if_name_len < sizeof(net_ifr.ifr_name)) {
 331                 memcpy(net_ifr.ifr_name, netconfig_get_default_ifname(), if_name_len);
 332                 net_ifr.ifr_name[if_name_len] = 0;
 333         } else {
 334                 INFO("Error : Interface name is too long");
 335                 goto err;
 336         }
 337
 338         if (ioctl(sd->chk_conflict_sd, SIOCGIFINDEX, &net_ifr) == -1) {
 339                 INFO("ioctl Failed. Error..... = %s\n",
 340                                 strerror_r(errno, error_buf, MAX_SIZE_ERROR_BUFFER));
 341                 goto err;
 342         }
 343
 344         ifindex = net_ifr.ifr_ifindex;
 345         /* Construct the destination address */
 346         addr.sll_family = AF_PACKET;
 347         addr.sll_ifindex = ifindex;
 348         addr.sll_halen = ETHER_ADDR_LEN;
 349         addr.sll_protocol = htons(ETH_P_ARP);
 350         memcpy(addr.sll_addr, broadcast_addr, ETHER_ADDR_LEN);
 351
 352         if (sendto(sd->chk_conflict_sd, &arp, sizeof(arp), 0,
 353                                 (struct sockaddr*)&addr, sizeof(addr)) < 0) {
 354                 INFO("Sending ARP Packet Failed. Error. = %s\n",
 355                                 strerror_r(errno, error_buf, MAX_SIZE_ERROR_BUFFER));
 356                 __close_channel_and_sock(sd);
 357                 if (__open_channel_and_sock(sd) == -1)
 358                         INFO("__open_channel_and_sock failed");
 359                 goto err;
 360         } else {
 361                 DBG("Sent ARP Packet \n");
 362         }
 363
 364         if (sd->timer_id) {
 365                 g_source_remove(sd->timer_id);
 366                 sd->timer_id = 0;
 367         }
 368
 369         if (conflict_state == NETCONFIG_IP_CONFLICT_STATE_CONFLICT_DETECTED || initial_bursts)
 370                 sd->timeout = BURST_ARP_SEND_TIME;
 371         else
 372                 sd->timeout = td.initial_time;
 373
 374         /* Adding timeout callback for arp request */
 375         sd->arp_reply_timer = g_timeout_add(1000, __arp_reply_timeout_cb,
 376                                         (gpointer) &sd->arp_reply_timer);
 377         return FALSE;
 378 err:
 379         if (sd->timer_id)
 380                 g_source_remove(sd->timer_id);
 381         sd->timer_id = g_timeout_add(sd->timeout, send_arp, sd);
 382         return FALSE;
 383 }
 384
 385 struct sock_data * start_ip_conflict_mon(void)
 386 {
 387         if (is_ip_conflict_detect_enabled == true) {
 388                 INFO("detection mode is set to true");
 389                 return NULL;
 390         }
 391
 392         initial_bursts = true;
 393
 394         sd = g_try_malloc0(sizeof(struct sock_data));
 395         if (sd == NULL) {
 396                 INFO("Failed to malloc sock_data");
 397                 return NULL;
 398         }
 399         sd->chk_conflict_data_id = -1;
 400         sd->chk_conflict_sd = -1;
 401
 402         if (__open_channel_and_sock(sd) == -1) {
 403                 INFO("__open_channel_and_sock failed");
 404                 g_free(sd);
 405                 return NULL;
 406         }
 407
 408         sd->timeout = td.initial_time;
 409         send_arp(sd);
 410         is_ip_conflict_detect_enabled = true;
 411         conflict_state = NETCONFIG_IP_CONFLICT_STATE_CONFLICT_NOT_DETECTED;
 412
 413         return sd;
 414 }
 415
 416 void stop_ip_conflict_mon()
 417 {
 418         INFO("+");
 419         if (sd == NULL) {
 420                 INFO("sd is NULL");
 421                 return;
 422         }
 423
 424         if (-1 < sd->chk_conflict_sd)
 425                 __close_channel_and_sock(sd);
 426
 427         if (sd->timer_id) {
 428                 g_source_remove(sd->timer_id);
 429         }
 430         g_free(sd);
 431         sd = NULL;
 432         is_ip_conflict_detect_enabled = false;
 433         conflict_state = NETCONFIG_IP_CONFLICT_STATE_UNKNOWN;
 434         INFO("Monitoring stopped");
 435 }
 436
 437 static void __netconfig_wifi_notify_ip_conflict(char *state, char *mac)
 438 {
 439         GVariantBuilder *builder = NULL;
 440
 441         builder = g_variant_builder_new(G_VARIANT_TYPE("a{sv}"));
 442         g_variant_builder_add(builder, "{sv}", "state", g_variant_new_string(state));
 443         g_variant_builder_add(builder, "{sv}", "mac", g_variant_new_string(mac));
 444
 445         wifi_emit_ip_conflict_event((Wifi *)get_wifi_object(), g_variant_builder_end(builder));
 446         g_variant_builder_unref(builder);
 447
 448         /* send notification using net-popup */
 449         if (!strcmp(state, "conflict"))
 450                 netconfig_send_notification_to_net_popup(NETCONFIG_ADD_IP_CONFLICT_NOTI, mac);
 451         else
 452                 netconfig_send_notification_to_net_popup(NETCONFIG_DEL_IP_CONFLICT_NOTI, mac);
 453
 454         return;
 455 }
 456
 457 gboolean handle_ip_conflict_set_enable(Wifi *wifi, GDBusMethodInvocation *context,
 458                                        bool detect)
 459 {
 460         g_return_val_if_fail(wifi != NULL, TRUE);
 461
 462         if (detect == false) {
 463                 if (sd != NULL)
 464                         stop_ip_conflict_mon();
 465                 else {
 466                         netconfig_error_dbus_method_return(context, NETCONFIG_ERROR_INTERNAL, "AlreadyExists");
 467                         return TRUE;
 468                 }
 469         } else {
 470                 if (sd == NULL) {
 471                         if (start_ip_conflict_mon() == NULL) {
 472                                 INFO("Failed to start IP conflict monitoring");
 473                                 netconfig_error_dbus_method_return(context,
 474                                                 NETCONFIG_ERROR_INTERNAL, "Failed");
 475                                 return TRUE;
 476                         }
 477                 } else {
 478                         netconfig_error_dbus_method_return(context, NETCONFIG_ERROR_INTERNAL, "AlreadyExists");
 479                         return TRUE;
 480                 }
 481         }
 482
 483         wifi_complete_ip_conflict_set_enable(wifi, context);
 484         return TRUE;
 485 }
 486
 487 gboolean handle_is_ip_conflict_detect_enabled(Wifi *wifi, GDBusMethodInvocation *context)
 488 {
 489         g_return_val_if_fail(wifi != NULL, TRUE);
 490         GVariant *param = NULL;
 491         param = g_variant_new("(b)", is_ip_conflict_detect_enabled);
 492         g_dbus_method_invocation_return_value(context, param);
 493         return TRUE;
 494 }
 495
 496 gboolean handle_set_ip_conflict_period(Wifi *wifi, GDBusMethodInvocation *context, guint initial_time)
 497 {
 498         g_return_val_if_fail(wifi != NULL, TRUE);
 499         INFO("%d", initial_time);
 500         if (initial_time > MAX_ARP_SEND_TIME || initial_time < MIN_ARP_SEND_TIME) {
 501                 netconfig_error_dbus_method_return(context,
 502                                                 NETCONFIG_ERROR_INTERNAL, "Failed");
 503                 return TRUE;
 504         }
 505
 506         td.initial_time = 1000 * initial_time;
 507         // remove timer
 508         stop_ip_conflict_mon();
 509         start_ip_conflict_mon();
 510         wifi_complete_set_ip_conflict_period(wifi, context);
 511         return TRUE;
 512 }
 513
 514 gboolean handle_get_ip_conflict_state(Wifi *wifi, GDBusMethodInvocation *context)
 515 {
 516         g_return_val_if_fail(wifi != NULL, TRUE);
 517         GVariant *param = NULL;
 518         param = g_variant_new("(u)", conflict_state);
 519         g_dbus_method_invocation_return_value(context, param);
 520         return TRUE;
 521 }
 522
 523 gboolean handle_get_ip_conflict_period(Wifi *wifi, GDBusMethodInvocation *context)
 524 {
 525         g_return_val_if_fail(wifi != NULL, TRUE);
 526         GVariant *param = NULL;
 527         param = g_variant_new("(u)", td.initial_time/1000);
 528         g_dbus_method_invocation_return_value(context, param);
 529         return TRUE;
 530 }