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
  42 #define ARP_PACKET_SIZE 60
  43 #define MAX_SIZE_ERROR_BUFFER 256
  44 #define IP_ADDRESS_LENGTH 4
  45 #define MAC_ADDRESS_LENGTH 6
  46 #define WLAN_MAC_ADDR_MAX 20
  47 #define ARP_SOURCE_IP "0.0.0.0"
  48 #define INITIAL_BURST_ARP_COUNT 5
  49
  50 #define CONFLICT_REMOVE_ITERATION_LIMIT 4
  51 #define MIN_ARP_SEND_TIME 20000
  52 #define BURST_ARP_SEND_TIME 3000
  53 #define MAX_ARP_SEND_TIME 32000
  54 #define GRATUITOUS_ARP_MAC_ADDR "00:00:00:00:00:00"
  55 #define UCHAR_TO_ADDRESS(hwaddr, buf) do {\
  56                 snprintf(buf, WLAN_MAC_ADDR_MAX,\
  57                 "%02X:%02X:%02X:%02X:%02X:%02X", hwaddr[0], hwaddr[1],\
  58                 hwaddr[2], hwaddr[3], hwaddr[4], hwaddr[5]);\
  59                 } while (0)
  60
  61 struct arp_message {
  62         /* Ethernet header */
  63         unsigned char   h_dest[MAC_ADDRESS_LENGTH];     /* destination ether addr */
  64         unsigned char   h_source[MAC_ADDRESS_LENGTH];   /* source ether addr */
  65         unsigned short  h_proto;                                /* packet type ID field */
  66
  67         /* ARP packet */
  68         unsigned short hw_type;                         /* hardware type(ARPHRD_ETHER) */
  69         unsigned short p_type;                          /* protocol type(ETH_P_IP) */
  70         unsigned char  hw_len;                          /* hardware address length */
  71         unsigned char  p_len;                                   /* protocol address length */
  72         unsigned short operation;                               /* ARP opcode */
  73         unsigned char  s_hwaddr[MAC_ADDRESS_LENGTH];            /* sender hardware address */
  74         unsigned char  s_IPaddr[IP_ADDRESS_LENGTH];             /* sender IP address */
  75         unsigned char  t_hwaddr[MAC_ADDRESS_LENGTH];            /* target hardware address */
  76         unsigned char  t_IPaddr[IP_ADDRESS_LENGTH];             /* target IP address */
  77         unsigned char  pad[18];                         /* pad for min. Ethernet payload (60 bytes) */
  78 };
  79
  80 typedef enum {
  81         NETCONFIG_IP_CONFLICT_STATE_UNKNOWN,
  82         NETCONFIG_IP_CONFLICT_STATE_CONFLICT_NOT_DETECTED,
  83         NETCONFIG_IP_CONFLICT_STATE_CONFLICT_DETECTED
  84 } ip_conflict_state_e;
  85
  86 struct timer_data {
  87         guint initial_time;
  88         guint timeout;
  89 };
  90 static struct timer_data td = {
  91         MIN_ARP_SEND_TIME, MIN_ARP_SEND_TIME
  92 };
  93
  94 int ioctl_sock;
  95 static bool initial_bursts = true;
  96 bool is_ip_conflict_detect_enabled = true;
  97 static gboolean send_arp(gpointer data);
  98 static void __netconfig_wifi_notify_ip_conflict(char *state, char *mac);
  99 ip_conflict_state_e conflict_state = NETCONFIG_IP_CONFLICT_STATE_CONFLICT_NOT_DETECTED;
 100
 101 struct sock_data *sd;
 102
 103 typedef unsigned int in_addr_t;
 104
 105 union uchar_to_uint {
 106         unsigned int uint;
 107         unsigned char uchar[IP_ADDRESS_LENGTH];
 108 };
 109
 110 static unsigned int __convert_uchar_to_uint(unsigned char b[IP_ADDRESS_LENGTH])
 111 {
 112         int idx = 0;
 113         union uchar_to_uint u;
 114         for (; idx < IP_ADDRESS_LENGTH; ++idx)
 115                 u.uchar[idx] = b[idx];
 116
 117         return u.uint;
 118 }
 119
 120 static gboolean __arp_reply_timeout_cb(gpointer data)
 121 {
 122         if (sd == NULL) {
 123                 INFO("Ignore timeout cb");
 124                 return G_SOURCE_REMOVE;
 125         }
 126
 127         sd->iteration++;
 128         sd->arp_reply_timer = -1;
 129         if (sd->timer_id != -1)
 130                 g_source_remove(sd->timer_id);
 131
 132         if (conflict_state != NETCONFIG_IP_CONFLICT_STATE_CONFLICT_NOT_DETECTED &&
 133                         sd->iteration == CONFLICT_REMOVE_ITERATION_LIMIT) {
 134                 sd->iteration = 0;
 135                 conflict_state = NETCONFIG_IP_CONFLICT_STATE_CONFLICT_NOT_DETECTED;
 136                 __netconfig_wifi_notify_ip_conflict("resolved", GRATUITOUS_ARP_MAC_ADDR);
 137                 initial_bursts = true;
 138         }
 139
 140         sd->timer_id = g_timeout_add(sd->timeout, send_arp, sd);
 141         return G_SOURCE_REMOVE;
 142 }
 143
 144 static gboolean __netconfig_check_arp_receive(GIOChannel *source,
 145                                                   GIOCondition condition, gpointer data)
 146 {
 147         struct sock_data *sd = data;
 148         gchar buffer[ARP_PACKET_SIZE] = {0, };
 149         gsize bytes_read = 0;
 150         struct arp_message arp_recv;
 151         char sbuf[WLAN_MAC_ADDR_MAX];
 152         char tbuf[WLAN_MAC_ADDR_MAX];
 153         const char *default_ip = NULL;
 154
 155         if (g_io_channel_read_chars(source, buffer, ARP_PACKET_SIZE,
 156                                 &bytes_read, NULL) == G_IO_STATUS_NORMAL) {
 157                 unsigned int target_ip = 0;
 158
 159                 memset(&arp_recv, 0, sizeof(arp_recv));
 160                 memcpy(&arp_recv, buffer, sizeof(buffer));
 161
 162                 default_ip = netconfig_get_default_ipaddress();
 163                 if (default_ip == NULL) {
 164                         INFO("ip address is not set yet");
 165                         goto out;
 166                 }
 167                 target_ip = inet_addr(default_ip);
 168
 169
 170                 /* Only handle ARP replies */
 171                 if (arp_recv.operation != htons(ARPOP_REPLY))
 172                         goto out;
 173
 174                 UCHAR_TO_ADDRESS(arp_recv.t_hwaddr, tbuf);
 175                 UCHAR_TO_ADDRESS(arp_recv.s_hwaddr, sbuf);
 176
 177                 int zero_mac = strcmp(tbuf , GRATUITOUS_ARP_MAC_ADDR);
 178                 if (zero_mac == 0) {
 179                         DBG("Broadcast packet.\n");
 180                         goto skip;
 181                 }
 182                 DBG("our mac= %s source mac= %s target mac= %s", netconfig_get_default_mac_address(), sbuf, tbuf);
 183                 int mac_cmp = strcmp(tbuf , netconfig_get_default_mac_address());
 184                 if (mac_cmp != 0) {
 185                         INFO("Packet not intended to us.\n");
 186                         goto out;
 187                 }
 188 skip:
 189                 mac_cmp = strcmp(sbuf, netconfig_get_default_mac_address());
 190                 DBG("target ip = %d source ip = %d", target_ip, __convert_uchar_to_uint(arp_recv.s_IPaddr));
 191                 if ((mac_cmp != 0) && (__convert_uchar_to_uint(arp_recv.s_IPaddr) == target_ip)) {
 192                         sd->iteration = 0;
 193                         if (conflict_state != NETCONFIG_IP_CONFLICT_STATE_CONFLICT_DETECTED) {
 194                                 INFO("ip conflict is detected !\n");
 195                                 conflict_state = NETCONFIG_IP_CONFLICT_STATE_CONFLICT_DETECTED;
 196                                 __netconfig_wifi_notify_ip_conflict("conflict", sbuf);
 197                                 sd->timeout = BURST_ARP_SEND_TIME;
 198                         }
 199
 200                         if (sd->arp_reply_timer != -1) {
 201                                 g_source_remove(sd->arp_reply_timer);
 202                                 sd->arp_reply_timer = -1;
 203                         }
 204
 205                         if (sd->timer_id)
 206                                 g_source_remove(sd->timer_id);
 207                         sd->timer_id = g_timeout_add(sd->timeout, send_arp, sd);
 208
 209                 }
 210         }
 211
 212 out:
 213         return TRUE;
 214 }
 215
 216 static gboolean send_arp(gpointer data)
 217 {
 218         struct sock_data *sd = data;
 219         struct ether_addr *source_mac = NULL;
 220         struct arp_message arp;
 221         char error_buf[MAX_SIZE_ERROR_BUFFER] = {0, };
 222         unsigned int source_ip = 0;
 223         unsigned int target_ip = 0;
 224         const unsigned char broadcast_addr[] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
 225         struct sockaddr_ll addr = {0};
 226         struct ifreq net_ifr;
 227         int ifindex = 0;
 228         errno = 0;
 229         const char *default_ip = 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         size_t if_name_len = strlen(netconfig_get_default_ifname());
 277         if (if_name_len < sizeof(net_ifr.ifr_name)) {
 278                 memcpy(net_ifr.ifr_name, netconfig_get_default_ifname(), if_name_len);
 279                 net_ifr.ifr_name[if_name_len] = 0;
 280         } else {
 281                 INFO("Error : Interface name is too long");
 282                 goto err;
 283         }
 284
 285         if (ioctl(sd->chk_conflict_sd, SIOCGIFINDEX, &net_ifr) == -1) {
 286                 strerror_r(errno, error_buf, MAX_SIZE_ERROR_BUFFER);
 287                 INFO("ioctl Failed. Error..... = %s\n", error_buf);
 288                 goto err;
 289         }
 290
 291         ifindex = net_ifr.ifr_ifindex;
 292         /* Construct the destination address */
 293         addr.sll_family = AF_PACKET;
 294         addr.sll_ifindex = ifindex;
 295         addr.sll_halen = ETHER_ADDR_LEN;
 296         addr.sll_protocol = htons(ETH_P_ARP);
 297         memcpy(addr.sll_addr, broadcast_addr, ETHER_ADDR_LEN);
 298
 299         if (sendto(sd->chk_conflict_sd, &arp, sizeof(arp), 0, (struct sockaddr*)&addr, sizeof(addr)) < 0) {
 300                 strerror_r(errno, error_buf, MAX_SIZE_ERROR_BUFFER);
 301                 INFO("Sending ARP Packet Failed. Error. = %s\n", error_buf);
 302                 /* close socket */
 303                 if (-1 < sd->chk_conflict_sd) {
 304                         close(sd->chk_conflict_sd);
 305                         sd->chk_conflict_sd = -1;
 306                 }
 307
 308                 /* reopen socket */
 309                 if ((sd->chk_conflict_sd = socket(AF_PACKET, SOCK_RAW, htons(ETH_P_ARP))) == -1) {
 310                         INFO("socket %d", sd->chk_conflict_sd);
 311                         strerror_r(errno, error_buf, MAX_SIZE_ERROR_BUFFER);
 312                         INFO("socket Failed. Error = %s\n", error_buf);
 313                 }
 314                 goto err;
 315         } else {
 316                 DBG("Sent ARP Packet \n");
 317         }
 318
 319         g_source_remove(sd->timer_id);
 320
 321         if (conflict_state == NETCONFIG_IP_CONFLICT_STATE_CONFLICT_DETECTED || initial_bursts)
 322                 sd->timeout = BURST_ARP_SEND_TIME;
 323         else
 324                 sd->timeout = td.initial_time;
 325
 326         /* Adding timeout callback for arp request */
 327         sd->arp_reply_timer = g_timeout_add(1000, __arp_reply_timeout_cb,
 328                                         (gpointer) &sd->arp_reply_timer);
 329         return FALSE;
 330 err:
 331         if (sd->timer_id)
 332                 g_source_remove(sd->timer_id);
 333         sd->timer_id = g_timeout_add(sd->timeout, send_arp, sd);
 334         return FALSE;
 335 }
 336
 337 struct sock_data * start_ip_conflict_mon(void)
 338 {
 339         if (is_ip_conflict_detect_enabled == false) {
 340                 INFO("detection mode is set to false");
 341                 return NULL;
 342         }
 343
 344         char error_buf[MAX_SIZE_ERROR_BUFFER] = {0, };
 345         initial_bursts = true;
 346
 347         sd = g_try_malloc0(sizeof(struct sock_data));
 348         if (sd == NULL) {
 349                 INFO("Failed to malloc sock_data");
 350                 return NULL;
 351         }
 352         sd->chk_conflict_data_id = -1;
 353         sd->chk_conflict_sd = -1;
 354         sd->timer_id = 0;
 355         sd->iteration = 0;
 356
 357         if ((sd->chk_conflict_sd = socket(AF_PACKET, SOCK_RAW, htons(ETH_P_ARP))) == -1) {
 358                 strerror_r(errno, error_buf, MAX_SIZE_ERROR_BUFFER);
 359                 INFO("socket Failed. Error = %s\n", error_buf);
 360                 g_free(sd);
 361                 return NULL;
 362         } else {
 363                 sd->chk_conflict_sock_io = g_io_channel_unix_new(sd->chk_conflict_sd);
 364                 if (sd->chk_conflict_sock_io == NULL) {
 365                         INFO("Failed to create channel");
 366                         INFO("Exit");
 367                         g_free(sd);
 368                         return NULL;
 369                 }
 370
 371                 g_io_channel_set_close_on_unref(sd->chk_conflict_sock_io, TRUE);
 372
 373                 if (G_IO_STATUS_NORMAL != g_io_channel_set_encoding(sd->chk_conflict_sock_io,
 374                                                                    NULL, NULL))
 375                         INFO("Failed to set encoding NULL on io channel");
 376                 if (G_IO_STATUS_NORMAL != g_io_channel_set_flags(sd->chk_conflict_sock_io,
 377                                                                 G_IO_FLAG_NONBLOCK, NULL))
 378                         INFO("Failed to set flags on io channel");
 379                 sd->chk_conflict_data_id = g_io_add_watch(sd->chk_conflict_sock_io, G_IO_IN,
 380                                                           __netconfig_check_arp_receive, sd);
 381                 DBG("socket %d", sd->chk_conflict_sd);
 382
 383                 sd->timeout = td.initial_time;
 384                 send_arp(sd);
 385                 return sd;
 386         }
 387 }
 388
 389 void stop_ip_conflict_mon()
 390 {
 391         INFO("+");
 392         GError* error = NULL;
 393         if (sd == NULL) {
 394                 INFO("sd is NULL");
 395                 return;
 396         }
 397         if (-1 < sd->chk_conflict_sd) {
 398                 if (G_IO_STATUS_NORMAL !=
 399                     g_io_channel_shutdown(sd->chk_conflict_sock_io, FALSE,
 400                                           &error)) {
 401                         INFO("Failure received while shutdown io channel[%d]:[%s]", error->code, error->message);
 402                         g_error_free(error);
 403                 }
 404                 g_io_channel_unref(sd->chk_conflict_sock_io);
 405                 g_source_remove(sd->chk_conflict_data_id);
 406                 sd->chk_conflict_data_id = -1;
 407                 close(sd->chk_conflict_sd);
 408                 sd->chk_conflict_sd = -1;
 409         }
 410         if (sd->timer_id > 0) {
 411                 g_source_remove(sd->timer_id);
 412                 sd->timer_id = 0;
 413         }
 414         g_free(sd);
 415         sd = NULL;
 416         INFO("Monitoring stopped");
 417 }
 418
 419 static void __netconfig_wifi_notify_ip_conflict(char *state, char *mac)
 420 {
 421         GVariantBuilder *builder = NULL;
 422
 423         builder = g_variant_builder_new(G_VARIANT_TYPE("a{sv}"));
 424         g_variant_builder_add(builder, "{sv}", "state", g_variant_new_string(state));
 425         g_variant_builder_add(builder, "{sv}", "mac", g_variant_new_string(mac));
 426
 427         wifi_emit_ip_conflict_event((Wifi *)get_wifi_object(), g_variant_builder_end(builder));
 428         g_variant_builder_unref(builder);
 429
 430         return;
 431 }
 432
 433 gboolean handle_ip_conflict_set_enable(Wifi *wifi, GDBusMethodInvocation *context,
 434                                        bool detect)
 435 {
 436         g_return_val_if_fail(wifi != NULL, FALSE);
 437
 438
 439         if (detect == false) {
 440                 is_ip_conflict_detect_enabled = false;
 441                 conflict_state = NETCONFIG_IP_CONFLICT_STATE_UNKNOWN;
 442                 if (sd != NULL)
 443                         stop_ip_conflict_mon();
 444                 else {
 445                         netconfig_error_dbus_method_return(context, NETCONFIG_ERROR_INTERNAL, "AlreadyExists");
 446                         wifi_complete_ip_conflict_set_enable(wifi, context);
 447                         return FALSE;
 448                 }
 449         } else {
 450                 is_ip_conflict_detect_enabled = true;
 451                 conflict_state = NETCONFIG_IP_CONFLICT_STATE_CONFLICT_NOT_DETECTED;
 452                 if (sd == NULL) {
 453                         if (start_ip_conflict_mon() == NULL) {
 454                                 INFO("Failed to start IP conflict monitoring");
 455                                 netconfig_error_dbus_method_return(context,
 456                                                 NETCONFIG_ERROR_INTERNAL, "Failed");
 457                                 wifi_complete_ip_conflict_set_enable(wifi, context);
 458                                 return FALSE;
 459                         }
 460                 } else {
 461                         netconfig_error_dbus_method_return(context, NETCONFIG_ERROR_INTERNAL, "AlreadyExists");
 462                         wifi_complete_ip_conflict_set_enable(wifi, context);
 463                         return FALSE;
 464                 }
 465         }
 466
 467         wifi_complete_ip_conflict_set_enable(wifi, context);
 468         return TRUE;
 469 }
 470
 471 gboolean handle_is_ip_conflict_detect_enabled(Wifi *wifi, GDBusMethodInvocation *context)
 472 {
 473         g_return_val_if_fail(wifi != NULL, FALSE);
 474         GVariant *param = NULL;
 475         param = g_variant_new("(b)", is_ip_conflict_detect_enabled);
 476         g_dbus_method_invocation_return_value(context, param);
 477         return TRUE;
 478 }
 479
 480 gboolean handle_set_ip_conflict_period(Wifi *wifi, GDBusMethodInvocation *context, guint initial_time)
 481 {
 482         g_return_val_if_fail(wifi != NULL, FALSE);
 483         if (initial_time < MAX_ARP_SEND_TIME && initial_time > MIN_ARP_SEND_TIME)
 484                 return FALSE;
 485
 486         td.initial_time = 1000 * initial_time;
 487         // remove timer
 488         stop_ip_conflict_mon();
 489         start_ip_conflict_mon();
 490         wifi_complete_set_ip_conflict_period(wifi, context);
 491         return TRUE;
 492 }
 493
 494 gboolean handle_get_ip_conflict_state(Wifi *wifi, GDBusMethodInvocation *context)
 495 {
 496         g_return_val_if_fail(wifi != NULL, FALSE);
 497         GVariant *param = NULL;
 498         param = g_variant_new("(u)", conflict_state);
 499         g_dbus_method_invocation_return_value(context, param);
 500         return TRUE;
 501 }
 502
 503 gboolean handle_get_ip_conflict_period(Wifi *wifi, GDBusMethodInvocation *context)
 504 {
 505         g_return_val_if_fail(wifi != NULL, FALSE);
 506         GVariant *param = NULL;
 507         param = g_variant_new("(u)", td.initial_time/1000);
 508         g_dbus_method_invocation_return_value(context, param);
 509         return TRUE;
 510 }