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 = 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         sd->timer_id = g_timeout_add(sd->timeout, send_arp, sd);
 140         return G_SOURCE_REMOVE;
 141 }
 142
 143 static gboolean __netconfig_check_arp_receive(GIOChannel *source,
 144                                                   GIOCondition condition, gpointer data)
 145 {
 146         struct sock_data *sd = data;
 147         gchar buffer[ARP_PACKET_SIZE] = {0, };
 148         gsize bytes_read = 0;
 149         struct arp_message arp_recv;
 150         char sbuf[WLAN_MAC_ADDR_MAX];
 151         char tbuf[WLAN_MAC_ADDR_MAX];
 152         const char *default_ip = NULL;
 153
 154         if (g_io_channel_read_chars(source, buffer, ARP_PACKET_SIZE,
 155                                 &bytes_read, NULL) == G_IO_STATUS_NORMAL) {
 156                 unsigned int target_ip = 0;
 157
 158                 memset(&arp_recv, 0, sizeof(arp_recv));
 159                 memcpy(&arp_recv, buffer, sizeof(buffer));
 160
 161                 default_ip = netconfig_get_default_ipaddress();
 162                 if (default_ip == NULL) {
 163                         INFO("ip address is not set yet");
 164                         goto out;
 165                 }
 166                 target_ip = inet_addr(default_ip);
 167
 168
 169                 /* Only handle ARP replies */
 170                 if (arp_recv.operation != htons(ARPOP_REPLY))
 171                         goto out;
 172
 173                 UCHAR_TO_ADDRESS(arp_recv.t_hwaddr, tbuf);
 174                 UCHAR_TO_ADDRESS(arp_recv.s_hwaddr, sbuf);
 175
 176                 int zero_mac = strcmp(tbuf , GRATUITOUS_ARP_MAC_ADDR);
 177                 if (zero_mac == 0) {
 178                         DBG("Broadcast packet.\n");
 179                         goto skip;
 180                 }
 181                 DBG("our mac= %s source mac= %s target mac= %s", netconfig_get_default_mac_address(), sbuf, tbuf);
 182                 int mac_cmp = strcmp(tbuf , netconfig_get_default_mac_address());
 183                 if (mac_cmp != 0) {
 184                         INFO("Packet not intended to us.\n");
 185                         goto out;
 186                 }
 187 skip:
 188                 mac_cmp = strcmp(sbuf, netconfig_get_default_mac_address());
 189                 DBG("target ip = %d source ip = %d", target_ip, __convert_uchar_to_uint(arp_recv.s_IPaddr));
 190                 if ((mac_cmp != 0) && (__convert_uchar_to_uint(arp_recv.s_IPaddr) == target_ip)) {
 191                         sd->iteration = 0;
 192                         if (conflict_state != NETCONFIG_IP_CONFLICT_STATE_CONFLICT_DETECTED) {
 193                                 INFO("ip conflict is detected !\n");
 194                                 conflict_state = NETCONFIG_IP_CONFLICT_STATE_CONFLICT_DETECTED;
 195                                 __netconfig_wifi_notify_ip_conflict("conflict", sbuf);
 196                                 sd->timeout = BURST_ARP_SEND_TIME;
 197                         }
 198
 199                         if (sd->arp_reply_timer != -1) {
 200                                 g_source_remove(sd->arp_reply_timer);
 201                                 sd->arp_reply_timer = -1;
 202                         }
 203
 204                         if (sd->timer_id)
 205                                 g_source_remove(sd->timer_id);
 206                         sd->timer_id = g_timeout_add(sd->timeout, send_arp, sd);
 207
 208                 }
 209         }
 210
 211 out:
 212         return TRUE;
 213 }
 214
 215 static gboolean send_arp(gpointer data)
 216 {
 217         struct sock_data *sd = data;
 218         struct ether_addr *source_mac = NULL;
 219         struct arp_message arp;
 220         char error_buf[MAX_SIZE_ERROR_BUFFER] = {0, };
 221         unsigned int source_ip = 0;
 222         unsigned int target_ip = 0;
 223         const unsigned char broadcast_addr[] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
 224         struct sockaddr_ll addr = {0};
 225         struct ifreq net_ifr;
 226         int ifindex = 0;
 227         errno = 0;
 228         const char *default_ip = NULL;
 229         const char *if_name = NULL;
 230         static int initial_send_arp_count = 0;
 231
 232         if (initial_bursts && initial_send_arp_count >= INITIAL_BURST_ARP_COUNT) {
 233                 initial_bursts = false;
 234                 initial_send_arp_count = 0;
 235         }
 236
 237         if (initial_bursts)
 238                 initial_send_arp_count++;
 239
 240         const char *mac = netconfig_get_default_mac_address();
 241         if (mac == NULL)
 242                 goto err;
 243         source_mac = ether_aton(mac);
 244         if (source_mac == NULL) {
 245                 INFO("Mac address is NULL");
 246                 goto err;
 247         }
 248
 249         memset(&arp, 0, sizeof(arp));
 250
 251         unsigned char  broadcast_mac_addr[MAC_ADDRESS_LENGTH];
 252         memset(broadcast_mac_addr, 0xff, sizeof(broadcast_mac_addr));
 253         memcpy(arp.h_dest, broadcast_mac_addr, MAC_ADDRESS_LENGTH);             /* MAC dest */
 254         memcpy(arp.h_source, source_mac, MAC_ADDRESS_LENGTH);                   /* MAC source */
 255
 256         arp.h_proto = htons(ETH_P_ARP);                                         /* protocol type (Ethernet) */
 257         arp.hw_type = htons(ARPHRD_ETHER);                                      /* hardware type */
 258         arp.p_type = htons(ETH_P_IP);                                           /* protocol type (ARP message) */
 259         arp.hw_len = MAC_ADDRESS_LENGTH;                                        /* hardware address length */
 260         arp.p_len = IP_ADDRESS_LENGTH;                                          /* protocol address length */
 261         arp.operation = htons(ARPOP_REQUEST);                                   /* ARP op code */
 262         default_ip = netconfig_get_default_ipaddress();
 263         if (default_ip == NULL) {
 264                 INFO("ip address is not set yet");
 265                 goto err;
 266         }
 267
 268         source_ip = inet_addr(ARP_SOURCE_IP);
 269         target_ip = inet_addr(default_ip);
 270         memcpy(arp.s_IPaddr, &source_ip, IP_ADDRESS_LENGTH);                    /* source IP address */
 271         memcpy(arp.s_hwaddr, source_mac, MAC_ADDRESS_LENGTH);                   /* source hardware address */
 272         memcpy(arp.t_IPaddr, &target_ip, IP_ADDRESS_LENGTH);                    /* target IP addressshek" */
 273
 274         memset(&net_ifr, 0, sizeof(net_ifr));
 275         /* ifreq structure creation */
 276         if_name = netconfig_get_default_ifname();
 277         size_t if_name_len = strlen(if_name);
 278
 279         if (if_name_len == 0) {
 280                 INFO("Error : Unable to get interface name ");
 281                 goto err;
 282         }
 283
 284         if (if_name_len < sizeof(net_ifr.ifr_name)) {
 285                 memcpy(net_ifr.ifr_name, netconfig_get_default_ifname(), if_name_len);
 286                 net_ifr.ifr_name[if_name_len] = 0;
 287         } else {
 288                 INFO("Error : Interface name is too long");
 289                 goto err;
 290         }
 291
 292         if (ioctl(sd->chk_conflict_sd, SIOCGIFINDEX, &net_ifr) == -1) {
 293                 strerror_r(errno, error_buf, MAX_SIZE_ERROR_BUFFER);
 294                 INFO("ioctl Failed. Error..... = %s\n", error_buf);
 295                 goto err;
 296         }
 297
 298         ifindex = net_ifr.ifr_ifindex;
 299         /* Construct the destination address */
 300         addr.sll_family = AF_PACKET;
 301         addr.sll_ifindex = ifindex;
 302         addr.sll_halen = ETHER_ADDR_LEN;
 303         addr.sll_protocol = htons(ETH_P_ARP);
 304         memcpy(addr.sll_addr, broadcast_addr, ETHER_ADDR_LEN);
 305
 306         if (sendto(sd->chk_conflict_sd, &arp, sizeof(arp), 0, (struct sockaddr*)&addr, sizeof(addr)) < 0) {
 307                 strerror_r(errno, error_buf, MAX_SIZE_ERROR_BUFFER);
 308                 INFO("Sending ARP Packet Failed. Error. = %s\n", error_buf);
 309                 /* close socket */
 310                 if (-1 < sd->chk_conflict_sd) {
 311                         close(sd->chk_conflict_sd);
 312                         sd->chk_conflict_sd = -1;
 313                 }
 314
 315                 /* reopen socket */
 316                 if ((sd->chk_conflict_sd = socket(AF_PACKET, SOCK_RAW, htons(ETH_P_ARP))) == -1) {
 317                         INFO("socket %d", sd->chk_conflict_sd);
 318                         strerror_r(errno, error_buf, MAX_SIZE_ERROR_BUFFER);
 319                         INFO("socket Failed. Error = %s\n", error_buf);
 320                 }
 321                 goto err;
 322         } else {
 323                 DBG("Sent ARP Packet \n");
 324         }
 325
 326         g_source_remove(sd->timer_id);
 327
 328         if (conflict_state == NETCONFIG_IP_CONFLICT_STATE_CONFLICT_DETECTED || initial_bursts)
 329                 sd->timeout = BURST_ARP_SEND_TIME;
 330         else
 331                 sd->timeout = td.initial_time;
 332
 333         /* Adding timeout callback for arp request */
 334         sd->arp_reply_timer = g_timeout_add(1000, __arp_reply_timeout_cb,
 335                                         (gpointer) &sd->arp_reply_timer);
 336         return FALSE;
 337 err:
 338         if (sd->timer_id)
 339                 g_source_remove(sd->timer_id);
 340         sd->timer_id = g_timeout_add(sd->timeout, send_arp, sd);
 341         return FALSE;
 342 }
 343
 344 struct sock_data * start_ip_conflict_mon(void)
 345 {
 346         if (is_ip_conflict_detect_enabled == true) {
 347                 INFO("detection mode is set to true");
 348                 return NULL;
 349         }
 350
 351         char error_buf[MAX_SIZE_ERROR_BUFFER] = {0, };
 352         initial_bursts = true;
 353
 354         sd = g_try_malloc0(sizeof(struct sock_data));
 355         if (sd == NULL) {
 356                 INFO("Failed to malloc sock_data");
 357                 return NULL;
 358         }
 359         sd->chk_conflict_data_id = -1;
 360         sd->chk_conflict_sd = -1;
 361         sd->timer_id = 0;
 362         sd->iteration = 0;
 363
 364         if ((sd->chk_conflict_sd = socket(AF_PACKET, SOCK_RAW, htons(ETH_P_ARP))) == -1) {
 365                 strerror_r(errno, error_buf, MAX_SIZE_ERROR_BUFFER);
 366                 INFO("socket Failed. Error = %s\n", error_buf);
 367                 g_free(sd);
 368                 return NULL;
 369         } else {
 370                 sd->chk_conflict_sock_io = g_io_channel_unix_new(sd->chk_conflict_sd);
 371                 if (sd->chk_conflict_sock_io == NULL) {
 372                         INFO("Failed to create channel");
 373                         INFO("Exit");
 374                         g_free(sd);
 375                         return NULL;
 376                 }
 377
 378                 g_io_channel_set_close_on_unref(sd->chk_conflict_sock_io, TRUE);
 379
 380                 if (G_IO_STATUS_NORMAL != g_io_channel_set_encoding(sd->chk_conflict_sock_io,
 381                                                                    NULL, NULL))
 382                         INFO("Failed to set encoding NULL on io channel");
 383                 if (G_IO_STATUS_NORMAL != g_io_channel_set_flags(sd->chk_conflict_sock_io,
 384                                                                 G_IO_FLAG_NONBLOCK, NULL))
 385                         INFO("Failed to set flags on io channel");
 386                 sd->chk_conflict_data_id = g_io_add_watch(sd->chk_conflict_sock_io, G_IO_IN,
 387                                                           __netconfig_check_arp_receive, sd);
 388                 DBG("socket %d", sd->chk_conflict_sd);
 389
 390                 sd->timeout = td.initial_time;
 391                 send_arp(sd);
 392                 is_ip_conflict_detect_enabled = true;
 393                 conflict_state = NETCONFIG_IP_CONFLICT_STATE_CONFLICT_NOT_DETECTED;
 394                 return sd;
 395         }
 396 }
 397
 398 void stop_ip_conflict_mon()
 399 {
 400         INFO("+");
 401         GError* error = NULL;
 402         if (sd == NULL) {
 403                 INFO("sd is NULL");
 404                 return;
 405         }
 406         if (-1 < sd->chk_conflict_sd) {
 407                 if (G_IO_STATUS_NORMAL !=
 408                     g_io_channel_shutdown(sd->chk_conflict_sock_io, FALSE,
 409                                           &error)) {
 410                         INFO("Failure received while shutdown io channel[%d]:[%s]", error->code, error->message);
 411                         g_error_free(error);
 412                 }
 413                 g_io_channel_unref(sd->chk_conflict_sock_io);
 414                 g_source_remove(sd->chk_conflict_data_id);
 415                 sd->chk_conflict_data_id = -1;
 416                 close(sd->chk_conflict_sd);
 417                 sd->chk_conflict_sd = -1;
 418         }
 419         if (sd->timer_id > 0) {
 420                 g_source_remove(sd->timer_id);
 421                 sd->timer_id = 0;
 422         }
 423         g_free(sd);
 424         sd = NULL;
 425         is_ip_conflict_detect_enabled = false;
 426         conflict_state = NETCONFIG_IP_CONFLICT_STATE_UNKNOWN;
 427         INFO("Monitoring stopped");
 428 }
 429
 430 static void __netconfig_wifi_notify_ip_conflict(char *state, char *mac)
 431 {
 432         GVariantBuilder *builder = NULL;
 433
 434         builder = g_variant_builder_new(G_VARIANT_TYPE("a{sv}"));
 435         g_variant_builder_add(builder, "{sv}", "state", g_variant_new_string(state));
 436         g_variant_builder_add(builder, "{sv}", "mac", g_variant_new_string(mac));
 437
 438         wifi_emit_ip_conflict_event((Wifi *)get_wifi_object(), g_variant_builder_end(builder));
 439         g_variant_builder_unref(builder);
 440
 441         /* send notification using net-popup */
 442         if (!strcmp(state, "conflict"))
 443                 netconfig_send_notification_to_net_popup(NETCONFIG_ADD_IP_CONFLICT_NOTI, mac);
 444         else
 445                 netconfig_send_notification_to_net_popup(NETCONFIG_DEL_IP_CONFLICT_NOTI, mac);
 446
 447         return;
 448 }
 449
 450 gboolean handle_ip_conflict_set_enable(Wifi *wifi, GDBusMethodInvocation *context,
 451                                        bool detect)
 452 {
 453         g_return_val_if_fail(wifi != NULL, TRUE);
 454
 455
 456         if (detect == false) {
 457                 if (sd != NULL)
 458                         stop_ip_conflict_mon();
 459                 else {
 460                         netconfig_error_dbus_method_return(context, NETCONFIG_ERROR_INTERNAL, "AlreadyExists");
 461                         wifi_complete_ip_conflict_set_enable(wifi, context);
 462                         return TRUE;
 463                 }
 464         } else {
 465                 if (sd == NULL) {
 466                         if (start_ip_conflict_mon() == NULL) {
 467                                 INFO("Failed to start IP conflict monitoring");
 468                                 netconfig_error_dbus_method_return(context,
 469                                                 NETCONFIG_ERROR_INTERNAL, "Failed");
 470                                 wifi_complete_ip_conflict_set_enable(wifi, context);
 471                                 return TRUE;
 472                         }
 473                 } else {
 474                         netconfig_error_dbus_method_return(context, NETCONFIG_ERROR_INTERNAL, "AlreadyExists");
 475                         wifi_complete_ip_conflict_set_enable(wifi, context);
 476                         return TRUE;
 477                 }
 478         }
 479
 480         wifi_complete_ip_conflict_set_enable(wifi, context);
 481         return TRUE;
 482 }
 483
 484 gboolean handle_is_ip_conflict_detect_enabled(Wifi *wifi, GDBusMethodInvocation *context)
 485 {
 486         g_return_val_if_fail(wifi != NULL, TRUE);
 487         GVariant *param = NULL;
 488         param = g_variant_new("(b)", is_ip_conflict_detect_enabled);
 489         g_dbus_method_invocation_return_value(context, param);
 490         return TRUE;
 491 }
 492
 493 gboolean handle_set_ip_conflict_period(Wifi *wifi, GDBusMethodInvocation *context, guint initial_time)
 494 {
 495         g_return_val_if_fail(wifi != NULL, TRUE);
 496         INFO("%d", initial_time);
 497         if (initial_time > MAX_ARP_SEND_TIME || initial_time < MIN_ARP_SEND_TIME) {
 498                 netconfig_error_dbus_method_return(context,
 499                                                 NETCONFIG_ERROR_INTERNAL, "Failed");
 500                 return TRUE;
 501         }
 502
 503         td.initial_time = 1000 * initial_time;
 504         // remove timer
 505         stop_ip_conflict_mon();
 506         start_ip_conflict_mon();
 507         wifi_complete_set_ip_conflict_period(wifi, context);
 508         return TRUE;
 509 }
 510
 511 gboolean handle_get_ip_conflict_state(Wifi *wifi, GDBusMethodInvocation *context)
 512 {
 513         g_return_val_if_fail(wifi != NULL, TRUE);
 514         GVariant *param = NULL;
 515         param = g_variant_new("(u)", conflict_state);
 516         g_dbus_method_invocation_return_value(context, param);
 517         return TRUE;
 518 }
 519
 520 gboolean handle_get_ip_conflict_period(Wifi *wifi, GDBusMethodInvocation *context)
 521 {
 522         g_return_val_if_fail(wifi != NULL, TRUE);
 523         GVariant *param = NULL;
 524         param = g_variant_new("(u)", td.initial_time/1000);
 525         g_dbus_method_invocation_return_value(context, param);
 526         return TRUE;
 527 }