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