contrib/hostapd-0.5.8/driver_wired.c

   1 /*
   2  * hostapd / Kernel driver communication for wired (Ethernet) drivers
   3  * Copyright (c) 2002-2005, Jouni Malinen <j@w1.fi>
   4  * Copyright (c) 2004, Gunter Burchardt <tira@isx.de>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  *
  10  * Alternatively, this software may be distributed under the terms of BSD
  11  * license.
  12  *
  13  * See README and COPYING for more details.
  14  */
  15
  16 #include "includes.h"
  17 #include <sys/ioctl.h>
  18
  19 #ifdef USE_KERNEL_HEADERS
  20 #include <asm/types.h>
  21 #include <linux/if_packet.h>
  22 #include <linux/if_ether.h>   /* The L2 protocols */
  23 #include <linux/if_arp.h>
  24 #include <linux/if.h>
  25 #else /* USE_KERNEL_HEADERS */
  26 #include <net/if_arp.h>
  27 #include <net/if.h>
  28 #include <netpacket/packet.h>
  29 #endif /* USE_KERNEL_HEADERS */
  30
  31 #include "hostapd.h"
  32 #include "ieee802_1x.h"
  33 #include "eloop.h"
  34 #include "sta_info.h"
  35 #include "driver.h"
  36 #include "accounting.h"
  37
  38
  39 struct wired_driver_data {
  40         struct driver_ops ops;
  41         struct hostapd_data *hapd;
  42
  43         int sock; /* raw packet socket for driver access */
  44         int dhcp_sock; /* socket for dhcp packets */
  45         int use_pae_group_addr;
  46 };
  47
  48 static const struct driver_ops wired_driver_ops;
  49
  50
  51 #define WIRED_EAPOL_MULTICAST_GROUP     {0x01,0x80,0xc2,0x00,0x00,0x03}
  52
  53
  54 /* TODO: detecting new devices should eventually be changed from using DHCP
  55  * snooping to trigger on any packet from a new layer 2 MAC address, e.g.,
  56  * based on ebtables, etc. */
  57
  58 struct dhcp_message {
  59         u_int8_t op;
  60         u_int8_t htype;
  61         u_int8_t hlen;
  62         u_int8_t hops;
  63         u_int32_t xid;
  64         u_int16_t secs;
  65         u_int16_t flags;
  66         u_int32_t ciaddr;
  67         u_int32_t yiaddr;
  68         u_int32_t siaddr;
  69         u_int32_t giaddr;
  70         u_int8_t chaddr[16];
  71         u_int8_t sname[64];
  72         u_int8_t file[128];
  73         u_int32_t cookie;
  74         u_int8_t options[308]; /* 312 - cookie */
  75 };
  76
  77
  78 static void wired_possible_new_sta(struct hostapd_data *hapd, u8 *addr)
  79 {
  80         struct sta_info *sta;
  81
  82         sta = ap_get_sta(hapd, addr);
  83         if (sta)
  84                 return;
  85
  86         HOSTAPD_DEBUG(HOSTAPD_DEBUG_MINIMAL, "Data frame from unknown STA "
  87                       MACSTR " - adding a new STA\n", MAC2STR(addr));
  88         sta = ap_sta_add(hapd, addr);
  89         if (sta) {
  90                 hostapd_new_assoc_sta(hapd, sta, 0);
  91                 accounting_sta_get_id(hapd, sta);
  92         } else {
  93                 HOSTAPD_DEBUG(HOSTAPD_DEBUG_MINIMAL, "Failed to add STA entry "
  94                               "for " MACSTR "\n", MAC2STR(addr));
  95         }
  96 }
  97
  98
  99 static void handle_data(struct hostapd_data *hapd, unsigned char *buf,
 100                         size_t len)
 101 {
 102         struct ieee8023_hdr *hdr;
 103         u8 *pos, *sa;
 104         size_t left;
 105
 106         /* must contain at least ieee8023_hdr 6 byte source, 6 byte dest,
 107          * 2 byte ethertype */
 108         if (len < 14) {
 109                 HOSTAPD_DEBUG(HOSTAPD_DEBUG_VERBOSE, "handle_data: too short "
 110                               "(%lu)\n", (unsigned long) len);
 111                 return;
 112         }
 113
 114         hdr = (struct ieee8023_hdr *) buf;
 115
 116         switch (ntohs(hdr->ethertype)) {
 117                 case ETH_P_PAE:
 118                         HOSTAPD_DEBUG(HOSTAPD_DEBUG_VERBOSE,
 119                                       "Received EAPOL packet\n");
 120                         sa = hdr->src;
 121                         wired_possible_new_sta(hapd, sa);
 122
 123                         pos = (u8 *) (hdr + 1);
 124                         left = len - sizeof(*hdr);
 125
 126                         ieee802_1x_receive(hapd, sa, pos, left);
 127                 break;
 128
 129         default:
 130                 HOSTAPD_DEBUG(HOSTAPD_DEBUG_MINIMAL,
 131                               "Unknown ethertype 0x%04x in data frame\n",
 132                               ntohs(hdr->ethertype));
 133                 break;
 134         }
 135 }
 136
 137
 138 static void handle_read(int sock, void *eloop_ctx, void *sock_ctx)
 139 {
 140         struct hostapd_data *hapd = (struct hostapd_data *) eloop_ctx;
 141         int len;
 142         unsigned char buf[3000];
 143
 144         len = recv(sock, buf, sizeof(buf), 0);
 145         if (len < 0) {
 146                 perror("recv");
 147                 return;
 148         }
 149
 150         handle_data(hapd, buf, len);
 151 }
 152
 153
 154 static void handle_dhcp(int sock, void *eloop_ctx, void *sock_ctx)
 155 {
 156         struct hostapd_data *hapd = (struct hostapd_data *) eloop_ctx;
 157         int len;
 158         unsigned char buf[3000];
 159         struct dhcp_message *msg;
 160         u8 *mac_address;
 161
 162         len = recv(sock, buf, sizeof(buf), 0);
 163         if (len < 0) {
 164                 perror("recv");
 165                 return;
 166         }
 167
 168         /* must contain at least dhcp_message->chaddr */
 169         if (len < 44) {
 170                 HOSTAPD_DEBUG(HOSTAPD_DEBUG_VERBOSE, "handle_dhcp: too short "
 171                               "(%d)\n", len);
 172                 return;
 173         }
 174
 175         msg = (struct dhcp_message *) buf;
 176         mac_address = (u8 *) &(msg->chaddr);
 177
 178         HOSTAPD_DEBUG(HOSTAPD_DEBUG_VERBOSE,
 179                       "Got DHCP broadcast packet from " MACSTR "\n",
 180                       MAC2STR(mac_address));
 181
 182         wired_possible_new_sta(hapd, mac_address);
 183 }
 184
 185
 186 static int wired_init_sockets(struct wired_driver_data *drv)
 187 {
 188         struct hostapd_data *hapd = drv->hapd;
 189         struct ifreq ifr;
 190         struct sockaddr_ll addr;
 191         struct sockaddr_in addr2;
 192         struct packet_mreq mreq;
 193         u8 multicastgroup_eapol[6] = WIRED_EAPOL_MULTICAST_GROUP;
 194         int n = 1;
 195
 196         drv->sock = socket(PF_PACKET, SOCK_RAW, htons(ETH_P_PAE));
 197         if (drv->sock < 0) {
 198                 perror("socket[PF_PACKET,SOCK_RAW]");
 199                 return -1;
 200         }
 201
 202         if (eloop_register_read_sock(drv->sock, handle_read, hapd, NULL)) {
 203                 printf("Could not register read socket\n");
 204                 return -1;
 205         }
 206
 207         memset(&ifr, 0, sizeof(ifr));
 208         snprintf(ifr.ifr_name, sizeof(ifr.ifr_name), "%s",
 209         hapd->conf->iface);
 210         if (ioctl(drv->sock, SIOCGIFINDEX, &ifr) != 0) {
 211                 perror("ioctl(SIOCGIFINDEX)");
 212                 return -1;
 213         }
 214
 215
 216         memset(&addr, 0, sizeof(addr));
 217         addr.sll_family = AF_PACKET;
 218         addr.sll_ifindex = ifr.ifr_ifindex;
 219         HOSTAPD_DEBUG(HOSTAPD_DEBUG_MINIMAL,
 220                       "Opening raw packet socket for ifindex %d\n",
 221                       addr.sll_ifindex);
 222
 223         if (bind(drv->sock, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
 224                 perror("bind");
 225                 return -1;
 226         }
 227
 228         /* filter multicast address */
 229         memset(&mreq, 0, sizeof(mreq));
 230         mreq.mr_ifindex = ifr.ifr_ifindex;
 231         mreq.mr_type = PACKET_MR_MULTICAST;
 232         mreq.mr_alen = 6;
 233         memcpy(mreq.mr_address, multicastgroup_eapol, mreq.mr_alen);
 234
 235         if (setsockopt(drv->sock, SOL_PACKET, PACKET_ADD_MEMBERSHIP, &mreq,
 236                        sizeof(mreq)) < 0) {
 237                 perror("setsockopt[SOL_SOCKET,PACKET_ADD_MEMBERSHIP]");
 238                 return -1;
 239         }
 240
 241         memset(&ifr, 0, sizeof(ifr));
 242         snprintf(ifr.ifr_name, sizeof(ifr.ifr_name), "%s", hapd->conf->iface);
 243         if (ioctl(drv->sock, SIOCGIFHWADDR, &ifr) != 0) {
 244                 perror("ioctl(SIOCGIFHWADDR)");
 245                 return -1;
 246         }
 247
 248         if (ifr.ifr_hwaddr.sa_family != ARPHRD_ETHER) {
 249                 printf("Invalid HW-addr family 0x%04x\n",
 250                        ifr.ifr_hwaddr.sa_family);
 251                 return -1;
 252         }
 253         memcpy(hapd->own_addr, ifr.ifr_hwaddr.sa_data, ETH_ALEN);
 254
 255         /* setup dhcp listen socket for sta detection */
 256         if ((drv->dhcp_sock = socket(PF_INET, SOCK_DGRAM, IPPROTO_UDP)) < 0) {
 257                 perror("socket call failed for dhcp");
 258                 return -1;
 259         }
 260
 261         if (eloop_register_read_sock(drv->dhcp_sock, handle_dhcp, hapd, NULL))
 262         {
 263                 printf("Could not register read socket\n");
 264                 return -1;
 265         }
 266
 267         memset(&addr2, 0, sizeof(addr2));
 268         addr2.sin_family = AF_INET;
 269         addr2.sin_port = htons(67);
 270         addr2.sin_addr.s_addr = INADDR_ANY;
 271
 272         if (setsockopt(drv->dhcp_sock, SOL_SOCKET, SO_REUSEADDR, (char *) &n,
 273                        sizeof(n)) == -1) {
 274                 perror("setsockopt[SOL_SOCKET,SO_REUSEADDR]");
 275                 return -1;
 276         }
 277         if (setsockopt(drv->dhcp_sock, SOL_SOCKET, SO_BROADCAST, (char *) &n,
 278                        sizeof(n)) == -1) {
 279                 perror("setsockopt[SOL_SOCKET,SO_BROADCAST]");
 280                 return -1;
 281         }
 282
 283         memset(&ifr, 0, sizeof(ifr));
 284         strncpy(ifr.ifr_ifrn.ifrn_name, hapd->conf->iface, IFNAMSIZ);
 285         if (setsockopt(drv->dhcp_sock, SOL_SOCKET, SO_BINDTODEVICE,
 286                        (char *) &ifr, sizeof(ifr)) < 0) {
 287                 perror("setsockopt[SOL_SOCKET,SO_BINDTODEVICE]");
 288                 return -1;
 289         }
 290
 291         if (bind(drv->dhcp_sock, (struct sockaddr *) &addr2,
 292                  sizeof(struct sockaddr)) == -1) {
 293                 perror("bind");
 294                 return -1;
 295         }
 296
 297         return 0;
 298 }
 299
 300
 301 static int wired_send_eapol(void *priv, const u8 *addr,
 302                             const u8 *data, size_t data_len, int encrypt,
 303                             const u8 *own_addr)
 304 {
 305         struct wired_driver_data *drv = priv;
 306         u8 pae_group_addr[ETH_ALEN] = WIRED_EAPOL_MULTICAST_GROUP;
 307         struct ieee8023_hdr *hdr;
 308         size_t len;
 309         u8 *pos;
 310         int res;
 311
 312         len = sizeof(*hdr) + data_len;
 313         hdr = wpa_zalloc(len);
 314         if (hdr == NULL) {
 315                 printf("malloc() failed for wired_send_eapol(len=%lu)\n",
 316                        (unsigned long) len);
 317                 return -1;
 318         }
 319
 320         memcpy(hdr->dest, drv->use_pae_group_addr ? pae_group_addr : addr,
 321                ETH_ALEN);
 322         memcpy(hdr->src, own_addr, ETH_ALEN);
 323         hdr->ethertype = htons(ETH_P_PAE);
 324
 325         pos = (u8 *) (hdr + 1);
 326         memcpy(pos, data, data_len);
 327
 328         res = send(drv->sock, (u8 *) hdr, len, 0);
 329         free(hdr);
 330
 331         if (res < 0) {
 332                 perror("wired_send_eapol: send");
 333                 printf("wired_send_eapol - packet len: %lu - failed\n",
 334                        (unsigned long) len);
 335         }
 336
 337         return res;
 338 }
 339
 340
 341 static int wired_driver_init(struct hostapd_data *hapd)
 342 {
 343         struct wired_driver_data *drv;
 344
 345         drv = wpa_zalloc(sizeof(struct wired_driver_data));
 346         if (drv == NULL) {
 347                 printf("Could not allocate memory for wired driver data\n");
 348                 return -1;
 349         }
 350
 351         drv->ops = wired_driver_ops;
 352         drv->hapd = hapd;
 353         drv->use_pae_group_addr = hapd->conf->use_pae_group_addr;
 354
 355         if (wired_init_sockets(drv)) {
 356                 free(drv);
 357                 return -1;
 358         }
 359
 360         hapd->driver = &drv->ops;
 361         return 0;
 362 }
 363
 364
 365 static void wired_driver_deinit(void *priv)
 366 {
 367         struct wired_driver_data *drv = priv;
 368
 369         drv->hapd->driver = NULL;
 370
 371         if (drv->sock >= 0)
 372                 close(drv->sock);
 373
 374         if (drv->dhcp_sock >= 0)
 375                 close(drv->dhcp_sock);
 376
 377         free(drv);
 378 }
 379
 380
 381 static const struct driver_ops wired_driver_ops = {
 382         .name = "wired",
 383         .init = wired_driver_init,
 384         .deinit = wired_driver_deinit,
 385         .send_eapol = wired_send_eapol,
 386 };
 387
 388 void wired_driver_register(void)
 389 {
 390         driver_register(wired_driver_ops.name, &wired_driver_ops);
 391 }